CN117714993A

CN117714993A - Communication method and related device

Info

Publication number: CN117714993A
Application number: CN202211103843.5A
Authority: CN
Inventors: 沙桐; 李秉肇; 张海森; 常俊仁
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2022-09-09
Filing date: 2022-09-09
Publication date: 2024-03-15
Also published as: WO2024051517A1

Abstract

The application discloses a communication method and a related device. The method comprises the following steps: the terminal equipment and the first network equipment carry out small data transmission SDT, the terminal equipment is interested in receiving or is receiving a first broadcast service from the first network equipment, the SDT is the transmission of data and/or signaling in Radio Resource Control (RRC) inactive dynamic state, and the first network equipment is the network equipment corresponding to a cell where the terminal equipment resides; the terminal device transmits first information to the first network device, the first information including information of a first broadcast service, the first information being used by the first network device to provide the first broadcast service to the terminal device. The method can realize that the network equipment corresponding to the service cell can acquire the multicast broadcast service information which the terminal equipment is interested in receiving or is receiving so as to reasonably schedule and transmit data under the small data transmission scene without UE context relocation, so that the terminal equipment can receive SDT and data of the multicast broadcast service.

Description

Communication method and related device

Technical Field

The present disclosure relates to the field of communications technologies, and in particular, to a communications method and a related device.

Background

In the inactive state of radio resource control (radio resource control, RRC), the terminal device (UE) may keep performing small data transmission (small data transmission, SDT) in the inactive state of RRC without switching to the RRC connected state for transmission for infrequent data transmission with smaller data amount, thereby reducing power consumption and signaling overhead caused by RRC state switching due to small data transmission requirements, and achieving the purpose of reducing UE power consumption.

However, in the small data transmission (SDT without UE context relocation) scenario without UE context relocation, if the terminal device is still interested in receiving or is receiving the multicast broadcast service, the data transmission of the SDT and the broadcast multicast service scheduled by the network device corresponding to the serving cell may exceed the receiving capability of the terminal device, resulting in packet loss or error code, and affecting the service quality.

Disclosure of Invention

The embodiment of the application provides a communication method and a related device, wherein under a small data transmission scene without UE context relocation, network equipment corresponding to a service cell can acquire multicast broadcast service information which is interested in receiving or is being received by the terminal equipment so as to reasonably schedule and transmit data, so that the terminal equipment can receive SDT and data of the multicast broadcast service.

In a first aspect, an embodiment of the present application provides a communication method, including:

the method comprises the steps that small data transmission SDT is carried out between terminal equipment and first network equipment, the terminal equipment is interested in receiving or is receiving first broadcast service from the first network equipment, the SDT is the transmission of data and/or signaling in Radio Resource Control (RRC) inactive state, and the first network equipment is network equipment corresponding to a cell where the terminal equipment resides;

the terminal device sends first information to the first network device, wherein the first information comprises information of the first broadcast service, and the first information is used for the first network device to provide the first broadcast service to the terminal device.

In this application, the first broadcast service may be one or more broadcast services. The information of the first broadcast service is information of the one or more broadcast services. The first multicast Session (MBS Session) may be one or more multicast sessions, which may also be understood as multicast services/multicast traffic.

In the embodiment of the application, a communication method is provided, a terminal device in RRC inactive state performs SDT with a first network device, and the terminal device is interested in receiving or is receiving a first broadcast service from the first network device, and the terminal device sends first information to the first network device, where the first information includes information of the first broadcast service, and the first information may specifically be multicast broadcast service (multicast broadcast service, MBS) interest indication information (MBS Interest Indication, MII) for indicating information of the MBS broadcast service that the terminal device is interested in receiving or is receiving, such as frequency of the MBS broadcast service, identification information of the MBS broadcast service, priority information of MBS broadcast compared with unicast and MBS multicast reception, and so on. The broadcast service that the terminal device is interested in receiving in the present application may also refer to a broadcast service that the terminal device does not receive but is to receive. According to the embodiment of the application, under the condition that the terminal equipment is in an RRC inactive state and performs SDT with the first network equipment, and the terminal equipment receives the first broadcast service from the first network equipment, the first network equipment can know that the terminal equipment still receives the first broadcast service in the SDT process by reporting the first information to the first network equipment, so that the first network equipment can properly schedule the SDT and the first broadcast service, the terminal equipment can also receive the data of the SDT and the broadcast service in a small data transmission scene without UE context relocation, and error codes and/or packet loss caused by exceeding the receiving capability of the terminal equipment in scheduling are avoided. The first network device is a network device corresponding to a serving cell where the terminal device resides in an RRC inactive state, and may also be a receiving gNB that performs SDT with the terminal device.

In this application, a broadcast service may refer to an MBS (multicast broadcast service, MBS) broadcast service (broadcast service), and a multicast service may refer to an MBS multicast service (multicast service). The SDT includes data and/or signaling for downstream/upstream SDTs.

In one possible embodiment, the method further comprises:

the terminal device receives data from the SDT and the first broadcast service of the first network device over different time slots. The SDT may be understood as downstream SDT data (DownLink SDT data). The reception of the SDT and the data of the first broadcast service on different time slots may be understood/replaced by reception of a physical downlink shared channel (physical downlink shared channel, PDSCH) for transmitting the SDT data and a PDSCH or group common PDSCH (group common physical downlink shared channel, GC-PDSCH) for transmitting the data of the first broadcast service on different time slots.

In this embodiment, a possible specific implementation manner of scheduling the SDT and the first broadcast service is provided, specifically, the first network device schedules the SDT and the first broadcast service through inter-slot time division multiplexing (inter-slot TDM), for example, data of the SDT is sent to the terminal device in a time slot 1, and data of the first broadcast service is sent to the terminal device in a time slot 2, so that the terminal device can receive the SDT and the first broadcast service from the first network device in different time slots. According to the embodiment of the application, in the SDT (SDT without UE context relocation) scenario without UE context relocation, if the terminal device is interested in receiving or is receiving the first broadcast service from the first network device, the first network device (i.e. the network device corresponding to the serving cell, also referred to as the receiving gNB of the SDT) may learn information of the first broadcast service received by the terminal device, so that the SDT and the data of the first broadcast service are scheduled on different time slots, and the terminal device may receive the SDT and the data of the first broadcast service sent by the first network device on different time slots even if the terminal device does not have the capability of receiving unicast data and broadcast data on the same time slot.

The terminal device sends the first information to the first network device, which may indicate that the terminal device supports receiving the MBS broadcast service, and the terminal device must choose to support time division multiplexing (inter-slot TDM) reception between the PDSCH for transmitting unicast data and the PDSCH/GC-PDSCH for transmitting MBS broadcast data. When the terminal device does not support to receive unicast data and MBS broadcast data in the same time slot, in the SDT scenario without context relocation, the first network device does not have UE capability information, if the first network device does not know that the terminal device is receiving the first broadcast service, when the first network device sends SDT data (SDT may be understood as a unicast transmission mode) and data of the first broadcast service in the same time slot, the terminal device may not receive the SDT and the broadcast data, or the terminal device may only receive one of the SDT and the broadcast data, which causes data error codes and/or packet loss, and affects service receiving quality. Thus, by the scheme of the application, the problems can be avoided.

In a possible implementation manner, before the terminal device sends the first information to the first network device, the method further includes:

the terminal equipment receives second information sent by the first network equipment and/or third information sent by the second network equipment, wherein the second network equipment is network equipment for sending RRC release information to the terminal equipment;

the terminal device sending first information to the first network device, including:

and the terminal equipment sends the first information to the first network equipment according to the second information and/or the third information.

In this embodiment, a possible specific embodiment of sending the first information is provided, specifically, before the terminal device sends the first information to the first network device, the terminal device further receives the second information sent by the first network device and/or the third information sent by the second network device, and determines, according to the second information and/or the third information, to send the first information to the first network device, where the first information includes information of a first broadcast service, and the first information may specifically be MII, which is used to indicate information of an MBS broadcast service that is interested in or being received by the terminal device, for example, a frequency of the MBS broadcast service, identification information of the MBS broadcast service, priority information of MBS broadcast compared with unicast and MBS multicast reception, and so on. According to the embodiment of the application, under the condition that the terminal equipment is in an RRC inactive state and performs SDT with the first network equipment and the terminal equipment receives the first broadcast service from the first network equipment, the reporting of the first information can be determined according to the second information sent by the first network equipment, or the reporting of the first information can be determined according to the third information sent by the second network equipment, or the reporting of the first information can be determined according to the second information sent by the first network equipment and the third information sent by the second network equipment; it is also understood that the first network device controls whether the terminal device is allowed to report the first information by means of the transmitted second information and/or the second network device controls whether the terminal device is allowed to report the first information by means of the transmitted third information. The second information and the third information may be the same information or different information.

In one possible implementation, the information of the first broadcast service includes temporary mobile group identity TMGI information; before the terminal device sends the first information to the first network device, the method further includes:

the terminal equipment receives fourth information sent by the first network equipment and/or fifth information sent by the second network equipment;

and the terminal equipment sends the first information to the first network equipment according to the fourth information and/or the fifth information, wherein the first information comprises TMGI information of the first broadcast service.

In this embodiment of the present application, a possible specific embodiment of sending the first information is provided, specifically, before the terminal device sends the first information to the first network device, the terminal device further receives fourth information sent by the first network device and/or fifth information sent by the second network device, and determines, according to the fourth information and/or the fifth information, to send the first information to the first network device, where the first information includes temporary mobile group identifier (temporary mobile group identity, TMGI) information of the first broadcast service. According to the embodiment of the application, in the scenario that the terminal equipment is in the RRC inactive state and performs SDT with the first network equipment, and the terminal equipment receives the first broadcast service from the first network equipment, the terminal equipment can determine that the first information includes the TMGI information of the first broadcast service according to the fourth information sent by the first network equipment, or determine that the second information includes the TMGI information of the first broadcast service according to the fifth information sent by the second network equipment, or determine that the second information includes the TMGI information of the first broadcast service according to the fourth information sent by the first network equipment and the fifth information sent by the second network equipment. The fourth information and the fifth information may be the same information or different information.

In a possible implementation, the third information and/or the fifth information is carried in an RRC release message; the method further comprises the steps of:

and the terminal equipment enters an RRC inactive state according to the RRC release message.

In this embodiment, a possible specific embodiment of transmitting the third information and/or the fifth information is provided, and in particular, the third information and/or the fifth information may be carried in an RRC release message, for example, the third information and/or the fifth information may be one indication bit (such as 1 bit) in the RRC release message, and the third information and the fifth information may be different information, indicated by two independent bits, or may be the same information, and indicated by the same bit. For example, when the third information and the fifth information are two independent information, the RRC release message includes the third information, or a bit position corresponding to the third information is 1, which indicates that the terminal device is allowed to report the first information (specifically, may be MII), or indicates that the terminal device is allowed to report the first information in an RRC inactive state, or indicates that the terminal device is allowed to report the first information in an SDT process, where the reporting is also understood that the second network device supports to receive the first information reported by the terminal device from the RRC inactive state, or the first information reported by the terminal device in the SDT process; for example, the RRC release message does not include the third information, or the bit position corresponding to the third information is 0, which indicates that the terminal device is not allowed to report/the second network device does not support receiving the first information (specifically, may be MII), or indicates that the terminal device that does not allow/support receiving the RRC inactive state does not report the first information, or indicates that the terminal device that does not allow/support receiving the first information is not allowed/supported to report the first information in the SDT process. Similarly, referring to the third information, in the setting and meaning of the fifth information, when the RRC release message includes the fifth information or the bit position corresponding to the fifth information is 1, it indicates that the first information allowed to be reported by the terminal device includes TMGI information of the broadcast service/the first information supported by the second network device and reported by the receiving terminal device includes TMGI information of the broadcast service, or indicates that the first information allowed to be received by the RRC inactive dynamic terminal device includes TMGI information of the broadcast service, or indicates that the first information allowed to be received by the receiving terminal device and reported by the SDT includes TMGI information of the broadcast service.

When the fifth information and the third information are the same information or the fifth information and the third information are the same indication bit/bit, for example, when the RRC release message includes the information or the bit/indication position is 1, indicating that the terminal device is allowed to report/support the second network device to receive the first information (may specifically be MII), and the first information may include TMGI information of the broadcast service; and when the RRC release message does not contain the information or the bit/indication position is 0, indicating that the terminal equipment is not allowed to report the first information. Other meaning examples refer to the description of the third information/the fifth information above, and are not repeated here.

Through the embodiment of the application, the second network device can control the reporting of the first information by the terminal device through the third information and/or the fifth information, and has better backward compatibility. For example, for an old version of network equipment, if the RRC non-active dynamic terminal equipment is not expected to report the first information, or if the first information reported by the terminal equipment is not expected to be received in the SDT process, the RRC release message may not include the third information and/or the fifth information, and then the terminal equipment may not report the first information; for the network device which can support the RRC inactive state terminal device to report the first information after upgrading/the network device can support the RRC inactive state terminal device to report the first information in the SDT process, the RRC release message can contain the third information and/or the fifth information.

In a possible embodiment, the second information, and/or the third information, and/or the fourth information, and/or the fifth information comprises system information.

In an embodiment of the present application, a possible specific embodiment of transmitting the second information, and/or the third information, and/or the fourth information, and/or the fifth information is provided, specifically, the second information, and/or the third information, and/or the fourth information, and/or the fifth information may include system information (System Information, SI); alternatively, the second information, and/or the third information, and/or the fourth information, and/or the fifth information may be transmitted in the form of a system information block (System Information Bloack, SIB).

In a possible implementation manner, the second information and/or the third information includes first system information, where the first system information is used to indicate a mapping relationship between a multicast broadcast service and a frequency, or is used to indicate configuration parameters of a multicast broadcast service control channel MCCH.

In the embodiment of the application, a possible specific embodiment of the second information and/or the third information is provided, and in particular, the second information and/or the third information may include the first system information; alternatively, the second information and/or the third information may be transmitted in the form of a first system information block. Wherein, the first system information is used to indicate the mapping relation between the multicast broadcast service and the frequency, for example, the first system information may correspond to a system information block SIB21; alternatively, the first system information may be used to indicate configuration parameters of a multicast broadcast service control channel (MBS control channel, MCCH), for example, may correspond to a system information block SIB20.

In a possible implementation manner, the fourth information and/or the fifth information includes second system information, where the second system information is used to indicate a mapping relationship between a multicast broadcast service and a frequency, or is used to indicate configuration parameters of a multicast broadcast service control channel MCCH.

In the embodiment of the application, a possible specific embodiment of the fourth information and/or the fifth information is provided, specifically, the fourth information and/or the fifth information may include second system information; alternatively, the fourth information and/or the fifth information may be transmitted in the form of a second system information block. Wherein, the second system information is used for indicating the mapping relation between the multicast broadcast service and the frequency, for example, the second system information can correspond to a system information block SIB21; alternatively, the second system information is used to indicate configuration parameters of a multicast broadcast service control channel (MBS control channel, MCCH), for example, may correspond to the system information block SIB20.

In a second aspect, embodiments of the present application provide a communication method, including:

the method comprises the steps that first network equipment receives first information sent by terminal equipment, wherein the first information comprises information of first broadcast services which are interested in being received or are being received by the terminal equipment, and the first network equipment is network equipment corresponding to a cell where the terminal equipment resides;

The first network device performs small data transmission SDT with the terminal device, and the first network device provides the first broadcast service for the terminal device, wherein the SDT is the transmission of data and/or signaling in a Radio Resource Control (RRC) inactive state.

In the embodiment of the present application, a communication method is provided, where a first network device receives first information sent by a terminal device, where the first information includes information of a first broadcast service that the terminal device is interested in receiving or is receiving, where the first information may specifically be multicast broadcast service (multicast broadcast service, MBS) interest indication information (MBS Interest Indication, MII) for indicating information of an MBS broadcast service that the terminal device is interested in receiving or is receiving, for example, frequency of an MBS broadcast service, identification information of an MBS broadcast service, priority information of MBS broadcast compared with unicast and MBS multicast reception, and the first network device provides the first broadcast service to the terminal device based on the first information when SDT is performed with the terminal device in RRC inactive state. The broadcast service that the terminal device is interested in receiving in the present application may also refer to a broadcast service that the terminal device does not receive but is to receive. According to the embodiment of the application, the first network equipment can know that the terminal equipment still receives the first broadcast service in the SDT process through the first information reported by the terminal equipment under the scene that the first network equipment performs SDT with the terminal equipment in the RRC inactive dynamic state and provides the first broadcast service for the terminal equipment in the RRC inactive dynamic state, so that the first network equipment can properly schedule the SDT and the first broadcast service, the terminal equipment can also receive data of the SDT and the broadcast service in a small data transmission scene without UE context relocation, and error codes and/or packet loss caused by exceeding the receiving capability of the terminal equipment in scheduling are avoided. The first network device is a network device corresponding to a serving cell where the terminal device resides in an RRC inactive state, and may also be a receiving gNB that performs SDT with the terminal device.

In one possible embodiment, the method further comprises:

the first network device sends the SDT and the data of the first broadcast service to the terminal device over different time slots. The SDT may be understood as downstream SDT data (DL SDT data). The data of the SDT and the first broadcast service transmitted on different time slots may be understood/replaced by PDSCH of the SDT and PDSCH/GC-PDSCH of the first broadcast service transmitted on different time slots or by PDSCH of the SDT and PDSCH/GC-PDSCH of the first broadcast service transmitted in an inter-slot time division multiplexing (inter-slot TDM) manner.

In this embodiment, a possible specific implementation manner of scheduling the SDT and the first broadcast service is provided, specifically, the first network device schedules the SDT and the first broadcast service through inter-slot time division multiplexing (inter-slot TDM), for example, data of the SDT is sent to the terminal device in a time slot 1, and data of the first broadcast service is sent to the terminal device in a time slot 2, so that the terminal device can receive the SDT and the first broadcast service from the first network device in different time slots. According to the embodiment of the application, in the SDT (SDT without UE context relocation) scenario without UE context relocation, if the terminal device is interested in receiving or is receiving the first broadcast service from the first network device, the first network device (i.e. the network device corresponding to the serving cell, which may also be referred to as a receiving gNB of the SDT) may learn information of the first broadcast service received by the terminal device, so that the terminal device may receive the SDT and the data of the first broadcast service from the first network device in different timeslots by scheduling the SDT and the data of the first broadcast service in different timeslots, even if the terminal device does not have the capability of receiving unicast data and broadcast data in the same timeslot.

The terminal device sends the first information to the first network device, which may indicate that the terminal device supports receiving the MBS broadcast service, and the terminal device must choose to support time division multiplexing (inter-slot TDM) reception between the PDSCH for transmitting unicast data and the PDSCH/GC-PDSCH for transmitting MBS broadcast data. When the terminal device does not support receiving unicast data and MBS broadcast data in the same time slot, in the SDT scenario without context relocation, the first network device does not have UE capability information, if the first network device does not know that the terminal device is receiving the first broadcast service, when the first network device schedules/sends SDT data (SDT may be understood as a unicast transmission mode) and data of the first broadcast service in the same time slot, the terminal device may not receive the SDT and the broadcast data, or the terminal device may only receive one of the SDT and the broadcast data, which causes data error codes and/or packet loss, and affects service receiving quality. Thus, by the scheme of the application, the problems can be avoided.

In one possible embodiment, the method further comprises:

the first network device sends the first information to a second network device, wherein the second network device is a network device for connecting the terminal device and a core network device;

the first network device receives sixth information from the second network device, the sixth information being used to indicate the first broadcast service, the sixth information being determined by the first information.

In an embodiment of the present application, a possible specific embodiment of information for indicating a first broadcast service is provided, specifically, a first network device sends first information to a second network device and receives sixth information from the second network device, where the second network device is a network device that connects a terminal device and a core network device, the sixth information is determined by the second network device according to the first information, and the sixth information is used to indicate the first broadcast service. It can be understood that the first information may be an RRC message, when the first network device receives the first information sent by the terminal device, the first network device does not have the complete context information of the terminal device, for example, the first network device only has the RLC context of the terminal device, but does not have PDCP and RRC related information (for example, PDCP context) of the terminal device, so that the first information cannot be interpreted, the first network device forwards the first information (may be an RLC data packet carrying the first information, for example, an RLC SDU or PDCP PDU) to the second network device, the second network device has the complete context information of the terminal device, for example, the second network device has the PDCP and RRC related information (for example, PDCP context) of the terminal device, so that the second network device can interpret the first information forwarded by the first network device based on the complete context information of the terminal device (for example, the RLC data packet carrying the first information forwarded by the first network device is received, obtains PDCP after processing of the PDCP layer, obtains PDCP SDU at the RRC layer, the first information is obtained by the first network device, and the second network device obtains the first information based on the first information, for example, the first network device is the first network interface is the sixth information; the sixth information and the first information may also be different information, for example, the sixth information contains part or all of the content of the first information, is determined/generated by the second network device, and is sent to the first network device through an interface (for example, an Xn interface) between the network devices.

In a possible embodiment, the first information includes TMGI information of the first broadcast service, where the TMGI information may include associated public land mobile network (public land mobile network, PLMN) information, such as one of PLMN-index or PLMN-Identity (PLMN Identity may also be simply referred to as PLMN ID). When the PLMN information is PLMN-index, after reading/decoding the first information, the second network device translates or converts the PLMN-index in the first information into PLMN-identity, and then sends the PLMN-identity to the first network device through sixth information, that is, the sixth information sent by the second network device is generated by replacing the PLMN-index in the first information with the PLMN-identity. In this way, it may be avoided that the first network device and the second network device understand the misalignment problem for the PLMN-index (e.g. the same PLMN-index corresponds to different PLMNs in the first network device and the second network device) when the PLMNs of the first network device and the second network device are different, or when the cell of the first network device and the cell of the second network device are different in the order of PLMNs in the PLMN list indicated in SIB1 (e.g. PLMN-identity infolist).

In one possible embodiment, the method further comprises:

The first network device sends a first request message to the second network device, wherein the first request message is used for requesting to acquire the context information of the terminal device for SDT;

the first network device receives partial context information of the terminal device, which is sent by the second network device, wherein the partial context information comprises seventh information, and the seventh information is used for indicating a second broadcast service received by the terminal device.

In an embodiment of the present application, a possible specific embodiment of information for indicating a second broadcast service is provided, specifically, the first network device sends a first request message to the second network device, and receives part of context information of the terminal device sent by the second network device in response to the first request message, where the first request message is used to request to acquire context information of the terminal device for SDT, and part of context information of the terminal device sent by the second network device in response to the first request message includes seventh information, where the seventh information is used to indicate the second broadcast service received by the terminal device. According to the embodiment of the application, the first network device performs SDT with the terminal device in RRC inactive state, and under the condition that the first network device provides the second broadcast service for the terminal device in RRC inactive state, the first network device can know that the terminal device is interested in receiving or is receiving the second broadcast service in the SDT process by sending the first request message to the second network device and receiving the seventh information in part of the context information of the terminal device provided by the second network device, so that the first network device can perform proper scheduling on the SDT and the second broadcast service, and the terminal device can also receive the data of the SDT and the second broadcast service in the small data transmission scene without UE context relocation, thereby avoiding error code and/or packet loss caused by exceeding the receiving capability of the terminal device.

In one possible embodiment, the method further comprises:

the first network device ignores the seventh information if the sixth information is received.

In this embodiment, a possible specific embodiment of the first network device performing corresponding broadcast service scheduling according to the sixth information or the seventh information is provided, specifically, the first network device ignores the seventh information when receiving the sixth information, which may be understood that the first network device performs scheduling on the SDT and the corresponding first broadcast service according to the sixth information when receiving the sixth information, whether the first network device receives the seventh information or not. When the first network device receives the broadcast service indicated in the seventh information and the broadcast service indicated in the sixth information, the broadcast service indicated in the sixth information is different, and the broadcast service 1, the broadcast service 2, and the broadcast service 3 are received by the terminal device in the seventh information, and the broadcast service 2 and the broadcast service 4 are received by the terminal device in the sixth information, the first network device considers that the broadcast service that the terminal device is interested in receiving or is receiving is the broadcast service 2 and the broadcast service 4, and the terminal device is not receiving the broadcast service 1 and the broadcast service 3. Optionally, when the first network device does not receive the sixth information and receives the seventh information, the first network device schedules the SDT and the corresponding second broadcast service according to the seventh information, so that the terminal device can also receive the data of the SDT and the second broadcast service in a small data transmission scenario without UE context relocation, and error codes and/or packet loss caused by scheduling exceeding the receiving capability of the terminal device are avoided.

In one possible embodiment, the method further comprises:

the first network device receives eighth information from the second network device, where the eighth information is used to instruct the terminal device to support or not support reception of M unicast data and N broadcast data in a frequency division multiplexing FDM in a same time slot, and M and N are integers greater than or equal to 1; and/or the number of the groups of groups,

the first network device receives ninth information from the second network device, where the ninth information is used to instruct the terminal device to support or not support time division multiplexing TDM reception of P unicast data and Q broadcast data in the same time slot, and P and Q are integers greater than or equal to 1.

Optionally, the eighth information is further configured to instruct the terminal device to support or not support, on a first frequency band (band) or a carrier of the first frequency band, frequency division multiplexing FDM reception of M unicast data and N broadcast data in the same timeslot, where M and N are integers greater than or equal to 1; the eighth information comprises an identification of the first frequency band;

optionally, the ninth information is further configured to instruct the terminal device to support or not support time division multiplexing TDM reception of P unicast data and Q broadcast data in the same time slot on the carrier of the second frequency band or the carrier of the second frequency band, where P and Q are integers greater than or equal to 1; the ninth information comprises an identification of the second frequency band; the first frequency band and the second frequency band may be the same frequency band or different frequency bands. In the embodiment of the present application, the unicast data may be understood as/replaced by PDSCH for transmitting unicast (unicasting) data, or PDSCH scrambled by radio network temporary identifier (Cell Radio Network Temporary Identifier, cell RNTI) of the cell; the broadcast data may be understood as/replaced with PDSCH/GC-PDSCH for transmitting MBS broadcast data or PDSCH scrambled by a group radio network temporary identifier (Group Radio Network Temporary Identifier, G-RNTI). Time/frequency division multiplexing of unicast data and broadcast data in the same time slot (intra-slot) can be understood as time/frequency division multiplexing of unicast PDSCH and GC-PDSCH broadcast by MBS in the same time slot (intra-slot).

In an embodiment of the present application, a possible specific embodiment of receiving the eighth information and/or the ninth information is provided, specifically, the first network device receives the eighth information and/or the ninth information from the second network device. According to the embodiment of the application, the first network device performs SDT with the terminal device in RRC inactive state, and under the scene that the first network device provides broadcast service for the terminal device in RRC inactive state, the first network device can know that the terminal device supports or does not support frequency division multiplexing TDM (time division multiplexing) reception or time division multiplexing TDM reception of one or more unicast data and one or more broadcast data in the same time slot according to the eighth information and/or the ninth information, so that the first network device can perform corresponding scheduling on the SDT and the broadcast service, so that the terminal device can also receive the data of the SDT and the broadcast service under the small data transmission scene without UE context relocation, and error code and/or packet loss caused by exceeding the receiving capability of the terminal device in scheduling is avoided.

In a third aspect, an embodiment of the present application provides a communication method, including:

the second network device sends small data transmission SDT and sixth information to the first network device, wherein the sixth information is used for indicating a first broadcast service, the first broadcast service is a broadcast service which is interested in or is being received by the terminal device, the second network device is a network device which connects the terminal device with the core network device, the first network device is a network device corresponding to a cell where the terminal device resides, the SDT is the transmission of data and/or signaling of radio resource control RRC inactive dynamic state of the terminal device, and the SDT is sent to the terminal device through the first network device.

In the embodiment of the present application, a possible specific implementation manner of sending the SDT and the sixth information is provided, specifically, the second network device sends the SDT and the sixth information to the first network device, where the sixth information is used to indicate that the terminal device is interested in receiving or is receiving the first broadcast service, and the first broadcast service indicated by the SDT and the sixth information is sent by the first network device to the terminal device. The broadcast service that the terminal device is interested in receiving in the present application may also refer to a broadcast service that the terminal device does not receive but is to receive. According to the embodiment of the application, the first network equipment performs SDT with the terminal equipment in RRC inactive state, and the second network equipment can make the first network equipment know that the terminal equipment still receives the first broadcast service in the SDT process by sending the sixth information to the first network equipment under the condition that the first network equipment provides the first broadcast service for the terminal equipment in RRC inactive state, so that the first network equipment can properly schedule the SDT and the first broadcast service, and can receive the data of the SDT and the broadcast service under the condition that the terminal equipment does not have small data transmission scene of UE context relocation, thereby avoiding error codes and/or packet loss caused by exceeding the receiving capability of the terminal equipment in scheduling. The first network device is a network device corresponding to a serving cell where the terminal device resides in an RRC inactive state, and may also be a receiving gNB that performs SDT with the terminal device.

In one possible embodiment, the method further comprises:

the second network device receives first information sent by the first network device, wherein the first information comprises information of the first broadcast service;

the second network device determines the sixth information according to the first information.

In an embodiment of the present application, a possible specific embodiment of determining sixth information is provided, specifically, the first network device sends first information to the second network device, where the first information includes information of the first broadcast service, and the second network device determines the sixth information according to the first information, where the sixth information is used to indicate the first broadcast service. It can be understood that the first information may be an RRC message, when the first network device receives the first information sent by the terminal device, the first network device does not have the complete context information of the terminal device, for example, the first network device only has the RLC context of the terminal device, but does not have PDCP and RRC related information (for example, PDCP context) of the terminal device, so that the first information cannot be interpreted, the first network device forwards the first information (may be an RLC data packet carrying the first information, for example, an RLC SDU or PDCP PDU) to the second network device, the second network device has the complete context information of the terminal device, for example, the second network device has the PDCP and RRC related information (for example, PDCP context) of the terminal device, so that the second network device can interpret the first information forwarded by the first network device based on the complete context information of the terminal device (for example, the RLC data packet carrying the first information forwarded by the first network device is received, obtains PDCP after processing of the PDCP layer, obtains PDCP SDU at the RRC layer, the first information is obtained by the first network device, and the second network device obtains the first information based on the first information, for example, the first network device is the first network interface is the sixth information; the sixth information and the first information may also be different information, for example, the sixth information contains part or all of the content of the first information, is determined/generated by the second network device, and is sent to the first network device through an interface (for example, an Xn interface) between the network devices.

In a possible embodiment, the first information includes TMGI information of the first broadcast service, where the TMGI information may include associated public land mobile network (public land mobile network, PLMN) information, such as one of PLMN-index or PLMN-Identity (PLMN Identity may also be simply referred to as PLMN ID). When the PLMN information is PLMN-index, after reading/decoding the first information, the second network device translates or converts the PLMN-index in the first information into PLMN-identity, and then sends the PLMN-identity to the first network device through sixth information, that is, the sixth information sent by the second network device is generated by replacing the PLMN-index in the first information with the PLMN-identity. In this way, it may be avoided that the first network device and the second network device understand the misalignment problem for the PLMN-index (i.e. the same PLMN-index corresponds to different PLMNs in the first network device and the second network device) when the PLMNs of the first network device and the second network device are different, or when the cell of the first network device and the cell of the second network device are different in the order of PLMNs in the PLMN list indicated in SIB1 (e.g. PLMN-identity infolist).

In one possible embodiment, the method further comprises:

The second network device receives a first request message sent by the first network device, where the first request message is used to request to acquire context information of the terminal device for SDT;

in response to the first request message, the second network device sends partial context information of the terminal device to the first network device, where the partial context information includes seventh information, and the seventh information is used to indicate a second broadcast service received by the terminal device.

In an embodiment of the present application, a possible specific embodiment of information for indicating a second broadcast service is provided, specifically, the second network device receives a first request message sent by the first network device, and sends part of context information of the terminal device to the first network device in response to the first request message, where the first request message is used to request to acquire the context information of the terminal device for SDT, and part of the context information of the terminal device sent by the second network device in response to the first request message includes seventh information, where the seventh information is used to indicate the second broadcast service received by the terminal device. According to the embodiment of the application, under the condition that the first network equipment performs SDT with the terminal equipment in RRC inactive state and the first network equipment provides the second broadcast service for the terminal equipment in RRC inactive state, the second network equipment can receive the first request message sent by the first network equipment and respond to the first request message to send the seventh message in the partial context information of the terminal equipment to the first network equipment, so that the first network equipment knows that the terminal equipment is possibly interested in receiving or receiving the second broadcast service in the SDT process, and therefore the first network equipment can properly schedule the SDT and the second broadcast service, and can receive the data of the SDT and the second broadcast service in a small data transmission scene without the UE context, thereby avoiding error codes and/or packet loss caused by exceeding the receiving capability of the terminal equipment in scheduling.

In a possible implementation manner, before the second network device sends the sixth information and/or the seventh information to the first network device, the method further includes:

and the second network equipment determines that the terminal equipment does not support receiving unicast data and broadcast data in the same time slot according to the capability information of the terminal equipment.

In this embodiment, a possible specific implementation manner of determining capability information of a terminal device is provided, specifically, the second network device may determine that the terminal device supports or does not support receiving unicast data and broadcast data in the same timeslot according to the capability information of the terminal device, when the second network device determines that the terminal device does not support receiving unicast data and broadcast data in the same timeslot, the second network device determines to send sixth information and/or seventh information to the first network device, so that the first network device may perform appropriate scheduling on SDT and broadcast service, for example, send SDT data and broadcast data to the terminal device in an inter-timeslot time division multiplexing (inter-slot TDM) manner, so that the terminal device may receive data of SDT and broadcast service, and avoid error codes and/or packet loss caused by that scheduling exceeds the receiving capability of the terminal device.

In a fourth aspect, embodiments of the present application provide a communication method, including:

the method comprises the steps that a terminal device receives small data transmission SDT and data of a first multicast session sent by a first network device, wherein the SDT is data and/or signaling transmission under a Radio Resource Control (RRC) inactive state, the first network device is network device corresponding to a cell where the terminal device resides, the first multicast session is a multicast session added by the terminal device, tenth information for indicating the first multicast session is sent to the first network device by a second network device, and the second network device is network device for connecting the terminal device and a core network device.

In this embodiment of the present application, a communication method is provided, where a terminal device in RRC inactive state performs SDT with a first network device, and the terminal device is interested in receiving or is receiving data of a first multicast session from the first network device, where the first multicast session is a multicast session that the terminal device joins, and the first network device sends the data of the first multicast session to the terminal device according to tenth information, where the tenth information is sent by a second network device to the first network device. The multicast session that the terminal device is interested in receiving in the present application may also refer to a multicast session that the terminal device does not receive but is to receive. According to the embodiment of the application, under the condition that the terminal equipment is in an RRC inactive state and performs SDT with the first network equipment, and the terminal equipment receives data of a first multicast session from the first network equipment, the second network equipment transmits tenth information for indicating the first multicast session to the first network equipment, so that the first network equipment knows that the terminal equipment also joins the first multicast session in the SDT process, when the first network equipment can provide the first multicast session for the terminal equipment, the first network equipment can properly schedule the SDT and the data of the first multicast session, for example, the SDT data and the data of the first multicast session are transmitted in a time slot time division multiplexing mode, or the SDT data and the data of the first multicast session are transmitted in a time slot frequency division multiplexing mode, and the like, so that the terminal equipment can also receive the SDT and the data of the first multicast session in the SDT scene without UE context relocation, and error codes and/or packet loss caused by exceeding the receiving capacity of the terminal equipment can be avoided. The first network device is a network device corresponding to a serving cell where the terminal device resides in an RRC inactive state, and may also be a receiving gNB that performs SDT with the terminal device.

In a possible implementation manner, the tenth information is carried in part of the context information of the terminal device, which is sent by the second network device to the first network device.

In an embodiment of the present application, a possible specific embodiment of tenth information is provided, specifically, the tenth information is carried in part of context information of a terminal device sent by the second network device to the first network device. According to the embodiment of the application, in a scenario that the terminal equipment is in an RRC inactive state and performs SDT with the first network equipment, and the terminal equipment receives data of a first multicast session from the first network equipment, the second network equipment sends part of context information of the terminal equipment to the first network equipment, wherein the part of context information of the terminal equipment comprises tenth information for indicating the first multicast session, so that the first network equipment knows that the terminal equipment also joins the first multicast session in the SDT process, and therefore the first network equipment can properly schedule the SDT and the data of the first multicast session, for example, send the SDT data and the data of the first multicast session in a time slot time division multiplexing mode, or send the SDT data and the data of the first multicast session in a time slot frequency division multiplexing mode, and the like, so that the terminal equipment can also receive the SDT and the data of the first multicast session in a small data transmission scenario without UE context relocation, and error codes and/or packet loss caused by exceeding the receiving capacity of the terminal equipment can be avoided.

In a fifth aspect, embodiments of the present application provide a communication method, including:

the first network device receives tenth information from the second network device, where the tenth information is used to instruct the terminal device to join the first multicast session, for example, the tenth information is TMGI information of the multicast session; the first network device is a network device corresponding to a cell where the terminal resides, and the second network device is a network device connecting the terminal device and a core network device;

the first network device sends small data transmission SDT and data of the first multicast session to the terminal device, wherein the SDT is data and/or signaling transmission under the Radio Resource Control (RRC) inactive state.

In this embodiment of the present application, a communication method is provided, where a first network device receives tenth information sent by a second network device, where the tenth information is used to indicate information of a first multicast session that a terminal device joins, where the tenth information may specifically be TMGI information of the first multicast session, the first network device performs SDT with the terminal device that is in an RRC inactive state, and the first network device provides data of the first multicast session to the terminal device based on the tenth information. According to the embodiment of the application, under the condition that the first network device performs SDT with the terminal device in RRC inactive state and the first network device provides data of the first multicast session for the terminal device in RRC inactive state, the first network device can know that the terminal device is added with the first multicast session and receives the data of the first multicast session in the SDT process through tenth information sent by the second network device, so that the first network device can properly schedule the data of the SDT and the first multicast session, for example, send the data of the SDT and the data of the first multicast session in a time slot time division multiplexing mode, or send the data of the SDT and the data of the first multicast session in a time slot frequency division multiplexing mode, and the like, so that the terminal device can also receive the data of the SDT and the multicast session in a small data transmission scene without repositioning of the UE context, and error codes and/or packet loss caused by scheduling exceeding the receiving capability of the terminal device are avoided. The first network device is a network device corresponding to a serving cell where the terminal device resides in an RRC inactive state, and may also be a receiving gNB that performs SDT with the terminal device.

In one possible implementation, the first network device receives tenth information from the second network device, including:

the first network device sends a second request message to the second network device, wherein the second request message is used for requesting to acquire the context information of the terminal device for SDT;

the first network device receives partial context information of the terminal device, which is sent by the second network device, wherein the partial context information comprises the tenth information.

In an embodiment of the present application, a possible specific embodiment of receiving tenth information is provided, specifically, the first network device sends a second request message to the second network device, and receives part of context information of the terminal device sent by the second network device in response to the second request message, where the second request message is used to request to obtain context information of the terminal device to perform SDT, and part of context information of the terminal device sent by the second network device in response to the second request message includes tenth information, where the tenth information is used to indicate information of a first multicast session that the terminal device joins. According to the embodiment of the application, under the condition that the first network device performs SDT with the terminal device in RRC inactive state and the first network device provides the first multicast session for the terminal device in RRC inactive state, the first network device can know that the terminal device also joins the first multicast session in the SDT process by sending the second request message to the second network device and receiving the tenth information in part of the context information of the terminal device provided by the second network device, so that the first network device can perform proper scheduling on the SDT and the data of the first multicast session, for example, send the SDT data and the data of the first multicast session in a time slot time division multiplexing mode, or send the SDT data and the data of the first multicast session in a time slot frequency division multiplexing mode, and the like, so that the terminal device can also receive the SDT and the data of the first multicast session in a small data transmission scene without the UE context relocation, and error and/or packet loss caused by scheduling exceeding the receiving capability of the terminal device are avoided.

In one possible embodiment, the method further comprises:

the first network device sends the SDT and the data of the first multicast session to the terminal device over different time slots. The SDT may be understood as downstream SDT data (DL SDT data). The transmitting of the data of the SDT and the first multicast session on different time slots may be understood/replaced by transmitting the PDSCH of the SDT and the PDSCH/GC-PDSCH of the first multicast session on different time slots or by transmitting the PDSCH of the SDT and the PDSCH/GC-PDSCH of the first multicast session in an inter-slot time division multiplexing (inter-slot TDM) manner.

In this embodiment, a possible specific implementation manner of scheduling SDT and data of a first multicast session is provided, specifically, the first network device schedules SDT and data of the first multicast session through inter-slot time division multiplexing (inter-slot TDM), for example, the data of SDT is sent to the terminal device in slot 1, and the data of the first multicast session is sent to the terminal device in slot 2, so that the terminal device can receive the SDT and the data of the first multicast session from the first network device in different slots. According to the embodiment of the application, in a SDT (SDT without UE context relocation) scenario without UE context relocation, if the terminal device joins a first multicast session from the first network device, the first network device (i.e. the network device corresponding to the serving cell, which may also be referred to as a receiving gNB of the SDT) may learn information of the first multicast session received by the terminal device, so that by scheduling data of the SDT and the first multicast session on different timeslots, the terminal device may receive data of the SDT and the first multicast session from the first network device on different timeslots even if the terminal device does not have the capability of receiving unicast data and multicast data on the same timeslot, and error codes and/or packet loss caused by scheduling exceeding the receiving capability of the terminal device are avoided.

In one possible embodiment, the method further comprises:

the first network device receives eleventh information from the second network device, where the eleventh information is used to instruct the terminal device to support or not support reception of M unicast data and N multicast data in a frequency division multiplexing FDM in a same time slot, where M and N are integers greater than or equal to 1; and/or the number of the groups of groups,

the first network device receives twelfth information from the second network device, where the twelfth information is used to indicate that the terminal device supports or does not support time division multiplexing TDM reception of P unicast data and Q multicast data in the same time slot, and P and Q are integers greater than or equal to 1.

Optionally, the eleventh information is further configured to instruct the terminal device to support or not support, on the first frequency band or a carrier of the first frequency band, frequency division multiplexing FDM reception of M unicast data and N multicast data in the same timeslot, where M and N are integers greater than or equal to 1; the eleventh information includes an identification of the first frequency band;

optionally, the twelfth information is further used to indicate that the terminal device supports or does not support time division multiplexing TDM reception of P unicast data and Q multicast data in the same time slot on the carrier of the second frequency band or the carrier of the second frequency band, where P and Q are integers greater than or equal to 1; the twelfth information comprises an identification of the second frequency band; the first frequency band and the second frequency band may be the same frequency band or different frequency bands.

In the embodiment of the present application, the unicast data may be understood as/replaced by PDSCH for transmitting unicast (unicasting) data, or PDSCH scrambled by radio network temporary identifier (Cell Radio Network Temporary Identifier, cell RNTI) of the cell; the multicast data may be understood/replaced by PDSCH/GC-PDSCH used for transmitting MBS multicast data or PDSCH scrambled by group radio network temporary identifier (Group Radio Network Temporary Identifier, G-RNTI). The time division multiplexing/frequency division multiplexing of unicast data and multicast data in the same time slot (intra-slot) can be understood as the time division multiplexing/frequency division multiplexing of unicast PDSCH and GC-PDSCH of MBS multicast in the same time slot (intra-slot).

In an embodiment of the present application, a possible specific embodiment of receiving the eleventh information and/or the twelfth information is provided, specifically, the first network device receives the eleventh information and/or the twelfth information from the second network device. According to the embodiment of the application, the first network device performs SDT with the terminal device in RRC inactive state, and under the scene that the first network device provides multicast session for the terminal device in RRC inactive state, the first network device can know that the terminal device supports or does not support frequency division multiplexing TDM (time division multiplexing) reception or time division multiplexing TDM reception of one or more unicast data and one or more multicast data in the same time slot according to eleventh information and/or twelfth information, so that the first network device can properly schedule the SDT and the multicast session data, and the terminal device can also receive the SDT and the multicast session data under the small data transmission scene without UE context relocation, thereby avoiding error code and/or packet loss caused by exceeding the receiving capability of the terminal device.

In a sixth aspect, embodiments of the present application provide a communication method, including:

the second network equipment sends small data transmission SDT and tenth information to the first network equipment, wherein the tenth information is used for indicating a first multicast session added by the terminal equipment, the first network equipment is network equipment corresponding to a cell where the terminal resides, and the second network equipment is network equipment for connecting the terminal equipment and core network equipment;

and the SDT and the data of the first multicast session are sent to the terminal equipment by the first network equipment, wherein the SDT is the transmission of data and/or signaling of the terminal equipment in Radio Resource Control (RRC) inactive state.

In this embodiment of the present application, a possible specific implementation manner of sending the SDT and tenth information is provided, specifically, the second network device sends the SDT and tenth information to the first network device, where the tenth information is used to indicate a first multicast session that the terminal device joins, and data of the first multicast session indicated by the SDT and tenth information is sent by the first network device to the terminal device. According to the embodiment of the application, the first network equipment performs SDT with the terminal equipment in RRC inactive state, and the second network equipment can send tenth information to the first network equipment under the scene that the first network equipment provides the first multicast session for the terminal equipment in RRC inactive state, so that the first network equipment knows that the terminal equipment still receives the data of the first multicast session in the SDT process, and therefore the first network equipment can properly schedule the data of the SDT and the first multicast session, and the terminal equipment can also receive the data of the SDT and the first multicast session under the small data transmission scene without UE context relocation, thereby avoiding error codes and/or packet loss caused by exceeding the capability of the terminal equipment in scheduling. The first network device is a network device corresponding to a serving cell where the terminal device resides in an RRC inactive state, and may also be a receiving gNB that performs SDT with the terminal device.

In one possible implementation, the second network device sends tenth information to the first network device, including:

the second network device receives a second request message sent by the first network device, where the second request message is used to request to acquire context information of the terminal device for SDT;

the second network device sends partial context information of the terminal device to the first network device, wherein the partial context information comprises the tenth information.

In this embodiment of the present application, a possible specific embodiment of sending tenth information is provided, specifically, the second network device receives a second request message sent by the first network device, and sends, in response to the second request message, part of context information of the terminal device to the first network device, where the second request message is used to request to obtain context information of the terminal device to perform SDT, and part of context information of the terminal device sent by the second network device in response to the second request message includes tenth information, where the tenth information is used to indicate information of a first multicast session that the terminal device joins. According to the embodiment of the application, under the condition that the first network equipment performs SDT with the terminal equipment in RRC inactive state and the first network equipment provides the first multicast session for the terminal equipment in RRC inactive state, the second network equipment can receive the second request message sent by the first network equipment and respond to the second request message to send the tenth information in partial context information of the terminal equipment to the first network equipment, so that the first network equipment knows that the terminal equipment also joins the first multicast session in the SDT process, and therefore the first network equipment can properly schedule the SDT and the data of the first multicast session, and can receive the SDT and the data of the first multicast session in a small data transmission scene without UE context, and error code and/or packet loss caused by exceeding the receiving capacity of the terminal equipment in scheduling is avoided.

In one possible implementation, the SDT and the data of the first multicast session are sent by the first network device to the terminal device on different time slots. The SDT may be understood as downstream SDT data (DL SDT data). The transmitting of the data of the SDT and the first multicast session on different time slots may be understood/replaced by transmitting the PDSCH of the SDT and the PDSCH/GC-PDSCH of the first multicast session on different time slots or by transmitting the PDSCH of the SDT and the PDSCH/GC-PDSCH of the first multicast session in an inter-slot time division multiplexing (inter-slot TDM) manner.

In one possible implementation, before the second network device sends tenth information to the first network device, the method further includes:

and the second network equipment determines that the terminal equipment does not support receiving unicast data and multicast data in the same time slot according to the capability information of the terminal equipment.

In this embodiment, a possible specific implementation manner of determining capability information of a terminal device is provided, specifically, the second network device may determine, according to the capability information of the terminal device, that the terminal device supports or does not support receiving unicast data and multicast data in the same timeslot, and when the second network device determines that the terminal device does not support receiving unicast data and multicast data in the same timeslot, the second network device determines to send tenth information to the first network device, so that the first network device may perform appropriate scheduling on SDT and multicast sessions, for example, send SDT data and multicast session data to the terminal device in an inter-timeslot time division multiplexing (inter-slot TDM) manner, so that the terminal device may receive SDT and multicast session data, and avoid error codes and/or packet loss caused by scheduling exceeding the receiving capability of the terminal device.

In a seventh aspect, embodiments of the present application provide a communication method, including:

the method comprises the steps that small data transmission SDT is carried out between a terminal device and a first network device, the terminal device joins a second multicast session from the first network device, the SDT is the transmission of data and/or signaling in Radio Resource Control (RRC) inactive state, and the first network device is the network device corresponding to a cell where the terminal device resides;

the terminal device sends thirteenth information to the first network device, the thirteenth information is used for indicating the second multicast session, and the thirteenth information is used for the first network device to send the second multicast session to the terminal device.

In an embodiment of the present application, a communication method is provided, where a terminal device in RRC inactive state performs SDT with a first network device, and the terminal device joins a second multicast session from the first network device, and the terminal device sends thirteenth information to the first network device, where the thirteenth information includes information of the second multicast session, and the thirteenth information may specifically be TMGI information of the second multicast session. According to the embodiment of the application, under the condition that the terminal equipment is in an RRC inactive state and performs SDT with the first network equipment, and the terminal equipment receives the second multicast session from the first network equipment, the first network equipment can know that the terminal equipment is still receiving the data of the second multicast session in the SDT process by reporting thirteenth information to the first network equipment, so that the first network equipment can properly schedule the SDT and the second multicast session, for example, the SDT data and the data of the second multicast session are sent in a time slot time division multiplexing mode, or the SDT data and the data of the second multicast session are sent in a time slot frequency division multiplexing mode, and the like, so that the terminal equipment can also receive the data of the SDT and the second multicast session in a small data transmission scene without UE context relocation, and error codes and/or packet loss caused by the fact that the scheduling exceeds the receiving capacity of the terminal equipment are avoided. The first network device is a network device corresponding to a serving cell where the terminal device resides in an RRC inactive state, and may also be a receiving gNB that performs SDT with the terminal device.

In a possible implementation, the thirteenth information is carried in a medium access control element MAC CE, or a radio resource control RRC message.

In the embodiments of the present application, a possible specific embodiment of the thirteenth information is provided, specifically, the thirteenth information may be carried in a media access control element (MAC CE), or a radio resource control RRC message. According to the embodiment of the application, under the condition that the terminal equipment is in an RRC inactive state and performs SDT with the first network equipment, and the terminal equipment receives data of a second multicast session from the first network equipment, the terminal equipment sends a MAC CE or RRC message to the first network equipment, wherein the MAC CE or RRC message comprises thirteenth information for indicating the second multicast session, so that the first network equipment knows that the terminal equipment also joins the second multicast session in the SDT process, and therefore the first network equipment can properly schedule the data of the SDT and the second multicast session, and can also receive the data of the SDT and the second multicast session in a small data transmission scene without UE context relocation, so that data errors and/or packet loss caused by exceeding the receiving capability of the terminal equipment in scheduling are avoided.

In one possible embodiment, the method further comprises:

the terminal device receives data from the SDT and the second multicast session of the first network device over different time slots. The SDT may be understood as downstream SDT data (DownLink SDT data). The receiving of the data of the SDT and the second multicast session on different time slots may be understood/replaced by receiving a physical downlink shared channel (physical downlink shared channel, PDSCH) for transmitting the SDT data and a PDSCH or a group common PDSCH (group common physical downlink shared channel, GC-PDSCH) for transmitting the data of the second multicast session on different time slots.

In this embodiment, a possible specific implementation manner of scheduling the SDT and the second multicast session is provided, specifically, the first network device schedules the SDT and the second multicast session through inter-slot time division multiplexing (inter-slot TDM), for example, data of the SDT is sent to the terminal device in a time slot 1, and data of the second multicast session is sent to the terminal device in a time slot 2, so that the terminal device can receive the SDT and the data of the second multicast session from the first network device in different time slots. According to the embodiment of the application, in a SDT (SDT without UE context relocation) scenario without UE context relocation, if the terminal device receives data of the second multicast session from the first network device, the first network device (i.e. the network device corresponding to the serving cell, also referred to as a receiving gNB of the SDT) may learn information of the second multicast session received by the terminal device, so that the SDT and the data of the second multicast session are scheduled on different time slots, and even if the terminal device does not have the capability of receiving unicast data and multicast data on the same time slot, the terminal device may receive the data of the SDT and the second multicast session from the first network device on different time slots, so as to avoid data error codes and/or packet loss caused by scheduling exceeding the receiving capability of the terminal device.

In an eighth aspect, embodiments of the present application provide a communication method, including:

the method comprises the steps that a first network device receives thirteenth information sent by a terminal device, wherein the thirteenth information is used for indicating a second multicast session, the second multicast session is a multicast session added by the terminal device, and the first network device is a network device corresponding to a cell where the terminal device resides;

the first network device performs small data transmission SDT with the terminal device, and the first network device sends the data of the second multicast session to the terminal device, wherein the SDT is the transmission of data and/or signaling in the radio resource control RRC inactive state.

In an embodiment of the present application, a communication method is provided, where a first network device receives thirteenth information sent by a terminal device, where the thirteenth information is used to indicate information of a second multicast session that the terminal device joins, where the thirteenth information may specifically be TMGI information of the second multicast session, the first network device performs SDT with the terminal device that is in an RRC inactive state, and the first network device provides the second multicast session to the terminal device based on the thirteenth information. According to the embodiment of the application, under the condition that the first network device performs SDT with the terminal device in RRC inactive state and the first network device provides the terminal device in RRC inactive state with the second multicast session, the first network device can know that the terminal device is still receiving the data of the second multicast session in the SDT process through thirteenth information reported by the terminal device, so that the first network device can properly schedule the data of the SDT and the second multicast session, for example, the data of the SDT and the data of the second multicast session are sent in a time slot time division multiplexing mode, or the data of the SDT and the data of the second multicast session are sent in a time slot frequency division multiplexing mode, and the like, so that the terminal device can also receive the data of the SDT and the second multicast session in a small data transmission scene without UE context relocation, and error codes and/or packet loss caused by the fact that the scheduling exceeds the receiving capability of the terminal device are avoided. The first network device is a network device corresponding to a serving cell where the terminal device resides in an RRC inactive state, and may also be a receiving gNB that performs SDT with the terminal device.

In a possible implementation manner, the first network device performs small data transmission SDT with the terminal device, and the first network device sends data of the second multicast session to the terminal device, including:

the first network device sends the SDT and the data of the second multicast session to the terminal device over different time slots. The SDT may be understood as downstream SDT data (DL SDT data). The data of the SDT and the second multicast session transmitted on different time slots may be understood/replaced by PDSCH of the SDT and PDSCH/GC-PDSCH of the second multicast session transmitted on different time slots or by PDSCH of the SDT and PDSCH/GC-PDSCH of the second multicast session transmitted in an inter-slot time division multiplexing (inter-slot TDM) manner.

In this embodiment, a possible specific implementation manner of scheduling the SDT and the second multicast session is provided, specifically, the first network device schedules the SDT and the second multicast session through inter-slot time division multiplexing (inter-slot TDM), for example, data of the SDT is sent to the terminal device in a time slot 1, and data of the second multicast session is sent to the terminal device in a time slot 2, so that the terminal device can receive the SDT and the data of the second multicast session from the first network device in different time slots. According to the embodiment of the application, in the SDT (SDT without UE context relocation) scenario without UE context relocation, if the terminal device joins the second multicast session from the first network device, the first network device (i.e. the network device corresponding to the serving cell, which may also be referred to as a receiving gNB of the SDT) may learn information of the second multicast session received by the terminal device, so that the terminal device may receive the data of the SDT and the second multicast session from the first network device in different timeslots by scheduling the data of the SDT and the second multicast session in different timeslots, even if the terminal device does not have the capability of receiving the unicast data and the multicast data in the same timeslot.

The terminal device sends thirteenth information to the first network device, which may indicate that the terminal device supports receiving the MBS multicast service, and the terminal device must choose to support time division multiplexing (inter-slot TDM) reception between PDSCH for transmitting unicast data and PDSCH/GC-PDSCH for transmitting MBS multicast data, so that the first network device sends SDT and data of the second multicast session according to time division multiplexing between timeslots, which may ensure that the terminal device can receive data of the second multicast session during SDT, and avoid error codes and/or packet loss, thereby ensuring service quality of SDT and MBS multicast service. When the terminal device does not support to receive the unicast data and the MBS multicast data in the same time slot, in the SDT scenario without context relocation, the first network device does not have UE capability information, if the first network device does not know that the terminal device is receiving the second multicast session, when the first network device schedules/sends the SDT data (SDT may be understood as a unicast transmission mode) and the data of the second multicast session in the same time slot, the terminal device may not receive the SDT and the multicast data, or the terminal device may only receive one of the SDT and the multicast data, which causes data error code and/or packet loss, and affects service receiving quality. Thus, by the scheme of the application, the problems can be avoided.

In the embodiments of the present application, a possible specific embodiment of the thirteenth information is provided, specifically, the thirteenth information may be carried in a medium access control element MAC CE, or a radio resource control RRC message. According to the embodiment of the invention, under the condition that the terminal equipment is in an RRC inactive state and performs SDT with the first network equipment, and the terminal equipment receives data of a second multicast session from the first network equipment, the first network equipment receives a MAC CE or RRC message sent by the terminal equipment, the MAC CE or RRC message comprises thirteenth information for indicating the second multicast session, so that the first network equipment knows that the terminal equipment also joins the second multicast session in the SDT process, and therefore, the first network equipment can properly schedule the data of the SDT and the second multicast session, and can also receive the data of the SDT and the second multicast session under the small data transmission scene without UE context relocation, thereby avoiding data error code and/or packet loss caused by the fact that the scheduling exceeds the receiving capability of the terminal equipment.

In a ninth aspect, embodiments of the present application provide a communication method, including:

the second network device sends a small data transmission SDT to the first network device; the data of the SDT and the second multicast session are sent to the terminal device by the first network device, the SDT is transmission of data and/or signaling of radio resource control RRC inactivity of the terminal device, the first network device is a network device corresponding to a cell where the terminal device resides, the second network device is a network device that connects the terminal device and the core network device, the second multicast session is a multicast session that indicates that the terminal device joins by thirteenth information, and the thirteenth information is from the terminal device.

In this embodiment, a possible specific implementation manner of sending the SDT is provided, specifically, the second network device sends the SDT to the first network device, where the SDT and the second multicast session indicated by the thirteenth information are sent by the first network device to the terminal device, and the thirteenth information is used to indicate the second multicast session that the terminal device joins. According to the embodiment of the application, under the condition that the first network device performs SDT with the terminal device in RRC inactive state and the first network device provides the second multicast session for the terminal device in RRC inactive state, the second network device can also receive the data of the second multicast session by sending thirteenth information to the first network device, so that the first network device knows that the terminal device still receives the data of the second multicast session in the SDT process, and therefore the first network device can properly schedule the data of the SDT and the data of the second multicast session, for example, send the data of the SDT and the data of the second multicast session in a time slot time division multiplexing mode, or send the data of the SDT and the data of the second multicast session in a time slot frequency division multiplexing mode, and the like, so that the terminal device can also receive the data of the SDT and the second multicast session in a small data transmission scene without UE context relocation, and avoid data error and/or packet loss caused by the scheduling exceeding the receiving capability of the terminal device.

In a tenth aspect, embodiments of the present application provide a communication device comprising means or units for performing the method according to any of the first to ninth aspects.

In one possible design, the apparatus includes:

a transceiver unit, configured to perform small data transmission SDT with a first network device, and is interested in receiving or receiving a first broadcast service from the first network device, where the SDT is a transmission of data and/or signaling in radio resource control RRC inactivity, and the first network device is a network device corresponding to a cell where the communication apparatus resides;

the transceiver unit is further configured to send first information to the first network device, where the first information includes information of the first broadcast service, and the first information is used for the first network device to provide the first broadcast service to the communication device.

In a possible implementation manner, the transceiver unit is further configured to receive the SDT and the first broadcast service from the first network device on different timeslots.

In a possible implementation manner, the transceiver unit is further configured to receive second information sent by the first network device and/or third information sent by a second network device, where the second network device is a network device that sends an RRC release message to the communication apparatus;

And the processing unit is used for sending the first information to the first network equipment through the receiving and transmitting unit according to the second information and/or the third information.

In a possible implementation manner, the transceiver unit is further configured to receive fourth information sent by the first network device and/or fifth information sent by the second network device;

the processing unit is further configured to send, according to the fourth information and/or the fifth information, the first information to the first network device through the transceiver unit, where the first information includes TMGI information of the first broadcast service

In a possible implementation, the third information and/or the fifth information is carried in an RRC release message;

the processing unit is further configured to enter an RRC inactive state according to the RRC release message.

Regarding the technical effects brought about by the tenth aspect and any possible embodiment, reference may be made to the description of the technical effects corresponding to the first aspect and the corresponding embodiments.

In another possible design, the apparatus includes:

a transceiver unit, configured to receive first information sent by a terminal device, where the first information includes information of a first broadcast service that the terminal device is interested in receiving or is receiving, and the communication device is a network device corresponding to a cell where the terminal device resides;

the transceiver unit is further configured to perform small data transmission SDT with the terminal device, and provide the first broadcast service to the terminal device, where the SDT is transmission of data and/or signaling in a radio resource control RRC inactive state.

In a possible implementation manner, the transceiver unit is further configured to send the SDT and the first broadcast service to the terminal device on different timeslots.

In a possible implementation manner, the transceiver unit is further configured to send the first information to a second network device, where the second network device is a network device that connects the terminal device and a core network device;

the transceiver unit is further configured to receive sixth information from the second network device, where the sixth information is used to indicate the first broadcast service, and the sixth information is determined by the first information.

In a possible implementation manner, the transceiver unit is further configured to send a first request message to the second network device, where the first request message is used to request to acquire context information of the terminal device for SDT;

the transceiver unit is further configured to receive partial context information of the terminal device sent by the second network device, where the partial context information includes seventh information, and the seventh information is used to indicate a second broadcast service received by the terminal device.

In a possible embodiment, the processing unit is configured to ignore the seventh information if the sixth information is received.

In a possible implementation manner, the transceiver unit is further configured to receive eighth information from the second network device, where the eighth information is used to instruct the terminal device to support or not support reception of M unicast data and N broadcast data in a frequency division multiplexing FDM in a same timeslot, where M and N are integers greater than or equal to 1; and/or the number of the groups of groups,

The transceiver unit is further configured to receive ninth information from the second network device, where the ninth information is used to instruct the terminal device to support or not support time division multiplexing TDM reception of P unicast data and Q broadcast data in the same time slot, and P and Q are integers greater than or equal to 1.

With regard to the technical effects brought about by the tenth aspect and any one of the possible embodiments, reference may be made to the description of the technical effects corresponding to the second aspect and the corresponding embodiments.

In another possible design, the apparatus includes:

the terminal equipment comprises a receiving and transmitting unit, a transmitting unit and a receiving unit, wherein the receiving and transmitting unit is used for transmitting small data transmission SDT and sixth information to first network equipment, the sixth information is used for indicating first broadcast service, the first broadcast service is broadcast service which is interested in receiving or is being received by the terminal equipment, the communication device is network equipment for connecting the terminal equipment and core network equipment, the first network equipment is network equipment corresponding to a cell where the terminal equipment resides, the SDT is the transmission of data and/or signaling of Radio Resource Control (RRC) inactivity dynamic state of the terminal equipment, and the SDT is transmitted to the terminal equipment through the first network equipment.

In a possible implementation manner, the transceiver unit is further configured to receive first information sent by the first network device, where the first information includes information of the first broadcast service;

and the processing unit is used for determining the sixth information according to the first information.

In a possible implementation manner, the transceiver unit is further configured to receive a first request message sent by the first network device, where the first request message is used to request to acquire context information of the terminal device for SDT;

the transceiver unit is further configured to send, in response to the first request message, partial context information of the terminal device to the first network device, where the partial context information includes seventh information, and the seventh information is used to indicate a second broadcast service received by the terminal device.

In a possible implementation manner, the processing unit is further configured to determine, according to the capability information of the terminal device, that the terminal device does not support receiving unicast data and broadcast data in the same timeslot.

Regarding the technical effects brought about by the tenth aspect and any possible embodiment, reference may be made to the description of the technical effects corresponding to the third aspect and the corresponding embodiments.

In another possible design, the apparatus includes:

the receiving and transmitting unit is configured to receive a small data transmission SDT and data of a first multicast session sent by a first network device, where the SDT is transmission of data and/or signaling under an inactive state of radio resource control RRC, the first network device is a network device corresponding to a cell where the communication apparatus resides, the first multicast session is a multicast session added by the communication apparatus, and tenth information for indicating the first multicast session is sent by a second network device to the first network device, where the second network device is a network device connected to the communication apparatus and a core network device.

In a possible implementation manner, the tenth information is carried in part of the context information of the communication device sent by the second network device to the first network device.

Regarding the technical effects brought about by the tenth aspect and any possible embodiment, reference may be made to the description of the technical effects corresponding to the fourth aspect and the corresponding embodiment.

In another possible design, the apparatus includes:

a transceiver unit, configured to receive tenth information from a second network device, where the tenth information is used to indicate a first multicast session to which a terminal device joins, the communication device is a network device corresponding to a cell where the terminal resides, and the second network device is a network device that connects the terminal device with a core network device;

The transceiver unit is further configured to send a small data transmission SDT and data of the first multicast session to the terminal device, where the SDT is transmission of data and/or signaling in a radio resource control RRC inactive state.

In a possible implementation manner, the transceiver unit is further configured to send a second request message to the second network device, where the second request message is used to request to acquire context information of the terminal device for SDT;

the transceiver is further configured to receive partial context information of the terminal device sent by the second network device, where the partial context information includes the tenth information.

In a possible implementation manner, the transceiver unit is further configured to send the SDT and the data of the first multicast session to the terminal device on different timeslots.

In a possible implementation manner, the transceiver unit is further configured to receive eleventh information from the second network device, where the eleventh information is used to instruct the terminal device to support or not support frequency division multiplexing FDM reception of M unicast data and N multicast data in a time slot, where M and N are integers greater than or equal to 1; and/or the number of the groups of groups,

The transceiver unit is further configured to receive twelfth information from the second network device, where the twelfth information is used to indicate that the terminal device supports or does not support time division multiplexing TDM reception of P unicast data and Q multicast data in a time slot, and P and Q are integers greater than or equal to 1.

Regarding the technical effects brought about by the tenth aspect and any possible embodiment, reference may be made to the description of the technical effects corresponding to the fifth aspect and the corresponding embodiment.

In another possible design, the apparatus includes:

a transceiver unit, configured to send a small data transmission SDT and tenth information to a first network device, where the tenth information is used to instruct a first multicast session to which a terminal device joins, the first network device is a network device corresponding to a cell where the terminal resides, and the communication device is a network device that connects the terminal device and a core network device;

In a possible implementation manner, the transceiver unit is further configured to receive a second request message sent by the first network device, where the second request message is used to request to acquire context information of the terminal device for SDT;

The transceiver unit is further configured to send partial context information of the terminal device to the first network device, where the partial context information includes the tenth information.

In one possible implementation, the SDT and the data of the first multicast session are sent by the first network device to the terminal device on different time slots.

In a possible implementation manner, the processing unit is configured to determine, according to the capability information of the terminal device, that the terminal device does not support receiving unicast data and multicast data in the same timeslot.

Regarding the technical effects brought about by the tenth aspect and any possible embodiment, reference may be made to the description of the technical effects corresponding to the sixth aspect and the corresponding embodiments.

In another possible design, the apparatus includes:

a transceiver unit, configured to perform small data transmission SDT with a first network device, and join a second multicast session from the first network device, where the SDT is a transmission of data and/or signaling in radio resource control RRC inactivity, and the first network device is a network device corresponding to a cell where the communication apparatus resides;

The transceiver unit is further configured to send thirteenth information to the first network device, where the thirteenth information is used to indicate the second multicast session, and the thirteenth information is used to send the second multicast session to the communication device by the first network device.

In a possible implementation, the transceiver unit is further configured to receive data of the SDT and the second multicast session from the first network device on different timeslots.

Regarding the technical effects brought about by the tenth aspect and any possible embodiment, reference may be made to the description of the technical effects corresponding to the seventh aspect and the corresponding embodiment.

In another possible design, the apparatus includes:

a transceiver unit, configured to receive thirteenth information sent by a terminal device, where the thirteenth information is used to indicate a second multicast session, where the second multicast session is a multicast session added by the terminal device, and the communication device is a network device corresponding to a cell where the terminal device resides;

The receiving and transmitting unit is further configured to perform small data transmission SDT with the terminal device, and send data of the second multicast session to the terminal device, where the SDT is transmission of data and/or signaling in a radio resource control RRC inactive state.

In a possible implementation manner, the transceiver unit is further configured to send the SDT and the data of the second multicast session to the terminal device on different timeslots.

Regarding the technical effects brought about by the tenth aspect and any one of the possible embodiments, reference may be made to the description of the technical effects corresponding to the eighth aspect and the corresponding embodiments.

In another possible design, the apparatus includes:

the receiving and transmitting unit is also used for transmitting small data transmission SDT to the first network equipment; the data of the SDT and the second multicast session are sent to the terminal device by the first network device, the SDT is transmission of data and/or signaling of radio resource control RRC inactivity of the terminal device, the first network device is a network device corresponding to a cell where the terminal resides, the communication device is a network device that connects the terminal device and the core network device, the second multicast session is a multicast session that indicates that the terminal device joins by using thirteenth information, and the thirteenth information is from the terminal device.

Regarding the technical effects brought about by the tenth aspect and any possible embodiment, reference may be made to the description of the technical effects corresponding to the ninth aspect and the corresponding embodiment.

In an eleventh aspect, embodiments of the present application provide a communication device that includes a processor. The processor is coupled to the memory and operable to execute instructions in the memory to implement the method of any one of the above-described first to ninth aspects and any one of the possible implementation manners. Optionally, the communication device further comprises a memory. Optionally, the communication device further comprises a communication interface, and the processor is coupled to the communication interface.

In a twelfth aspect, embodiments of the present application provide a communication apparatus, including: logic circuitry and a communication interface. The communication interface is used for receiving information or sending information; the logic is configured to receive information or send information through the communication interface, so that the communication device performs the method of any one of the first to ninth aspects and any possible implementation manner.

In a thirteenth aspect, embodiments of the present application provide a computer-readable storage medium storing a computer program (which may also be referred to as code, or instructions); the computer program, when run on a computer, causes the method of any one of the above-mentioned first to ninth aspects and any one of the possible implementation manners to be implemented.

In a fourteenth aspect, embodiments of the present application provide a computer program product comprising: computer programs (also referred to as code, or instructions); the computer program, when executed, causes a computer to perform the method of any one of the above-mentioned first to ninth aspects and any one of the possible implementation manners.

In a fifteenth aspect, embodiments of the present application provide a chip comprising a processor for executing instructions, which when executed by the processor cause the chip to perform the method of any one of the first to ninth aspects and any one of the possible implementations. Optionally, the chip further comprises a communication interface, and the communication interface is used for receiving signals or sending signals.

In a sixteenth aspect, embodiments of the present application provide a communication system, where the communication system includes at least one communication device according to the tenth aspect, or a communication device according to the eleventh aspect, or a communication device according to the twelfth aspect, or a chip according to the fifteenth aspect.

In a seventeenth aspect, an embodiment of the present application provides a communication system, including a terminal device, a first network device, and a second network device; wherein the terminal device is configured to perform the method of the first aspect and any possible implementation manner, the first network device is configured to perform the method of the second aspect and any possible implementation manner, and the second network device is configured to perform the method of the third aspect and any possible implementation manner; or the terminal device is configured to perform the method of the fourth aspect and any possible implementation manner, the first network device is configured to perform the method of the fifth aspect and any possible implementation manner, and the second network device is configured to perform the method of the sixth aspect and any possible implementation manner; or the terminal device is configured to perform the method of the seventh aspect and any possible implementation manner, the first network device is configured to perform the method of the eighth aspect and any possible implementation manner, and the second network device is configured to perform the method of the ninth aspect and any possible implementation manner.

Further, in performing the method according to any one of the first to ninth aspects and any possible implementation manner of the first to ninth aspects, the process of sending information and/or receiving information and the like in the method may be understood as a process of outputting information by a processor and/or a process of receiving input information by a processor. In outputting the information, the processor may output the information to a transceiver (or communication interface, or transmission module) for transmission by the transceiver. After output by the processor, the information may also need to be processed further before reaching the transceiver. Similarly, when the processor receives input information, the transceiver (or communication interface, or transmission module) receives the information and inputs it to the processor. Further, after the transceiver receives the information, the information may need to be further processed before being input to the processor.

Based on the above principle, for example, the transmission information mentioned in the foregoing method may be understood as processor output information. For another example, receiving information may be understood as a processor receiving input information.

Alternatively, the operations of transmitting, receiving, etc. related to the processor may be more generally understood as operations of outputting and receiving, inputting, etc. by the processor, unless otherwise specified, or if not contradicted by actual action or inherent logic in the related description.

Alternatively, in performing the methods according to any one of the first to ninth aspects and any one of the possible implementation manners of the first to ninth aspects, the processor may be a processor dedicated to performing the methods, or may be a processor that performs the methods by executing computer instructions in a memory, such as a general-purpose processor. The Memory may be a non-transitory (non-transitory) Memory, such as a Read Only Memory (ROM), which may be integrated on the same chip as the processor, or may be separately provided on different chips, and the type of the Memory and the manner of providing the Memory and the processor are not limited in this embodiment of the present application.

In one possible embodiment, the at least one memory is located outside the device.

In yet another possible embodiment, the at least one memory is located within the device.

In yet another possible embodiment, a portion of the at least one memory is located within the device and another portion of the at least one memory is located outside the device.

In this application, the processor and the memory may also be integrated in one device, i.e. the processor and the memory may also be integrated together.

In the embodiment of the present application, in a scenario where the terminal device is in an RRC inactive state and performs SDT with the first network device, and the terminal device receives a broadcast service or a multicast session from the first network device, the first network device may be enabled to know that the terminal device is still receiving the broadcast service or the multicast session in the SDT process by reporting to the first network device a broadcast service or a multicast session that the terminal device is interested in receiving or receiving, so that the first network device may perform appropriate scheduling on the SDT, the broadcast service and/or the multicast session, and may also receive data of the SDT and the multicast broadcast service in a small data transmission scenario without UE context relocation, so as to avoid data errors and/or packet loss caused by scheduling exceeding the receiving capability of the terminal device.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic diagram of a communication system according to an embodiment of the present application;

fig. 2 is a schematic diagram of state switching of a terminal device according to an embodiment of the present application;

fig. 3 is a schematic RRC connection recovery flow diagram of a terminal device according to an embodiment of the present application;

fig. 4 is a schematic flow chart of a communication method according to an embodiment of the present application;

fig. 5 is a flow chart of another communication method according to an embodiment of the present application;

fig. 6 is a flow chart of another communication method according to an embodiment of the present application;

fig. 7 is a flow chart of another communication method according to an embodiment of the present application;

fig. 8 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 9 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 10 is a schematic structural diagram of a chip according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, embodiments of the present application will be described below with reference to the accompanying drawings in the embodiments of the present application.

The terms first and second and the like in the description, in the claims and in the drawings, are used for distinguishing between different objects and not for describing a particular sequential order. Furthermore, the terms "comprising," "including," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion. Such as a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to the list of steps or elements but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It will be explicitly and implicitly understood by those skilled in the art that in various embodiments of the present application, terms and/or descriptions between various embodiments are consistent and may be mutually referenced, and technical features in different embodiments may be combined to form new embodiments according to their inherent logical relationships, if not specifically stated or logically conflicting.

It should be understood that, in the present application, "at least one (item)" means one or more, "a plurality" means two or more, "at least two (items)" means two or three and three or more, "and/or" for describing an association relationship of an association object, three kinds of relationships may exist, for example, "a and/or B" may mean: only a, only B and both a and B are present, wherein a, B may be singular or plural. The character "/" generally indicates that the context-dependent object is an "or" relationship. "at least one of" or the like means any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one (one) of a, b or c may represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", wherein a, b, c may be single or plural.

The method provided by the application can be applied to various communication systems, such as an internet of things (internet of things, ioT) system, a narrowband internet of things (narrow band internet of things, NB-IoT) system, a long term evolution (long term evolution, LTE) system, a fifth generation (5G) communication system, a new communication system (such as 6G) in future communication development, and the like.

The technical solutions provided herein may also be applied to machine-type communication (machine type communication, MTC), inter-machine communication long term evolution technology (long term evolution-machine, LTE-M), device-to-device (D2D) networks, machine-to-machine (machine to machine, M2M) networks, internet of things (internet of things, ioT) networks, or other networks. The IoT network may include, for example, an internet of vehicles. The communication modes in the internet of vehicles system are generally called as vehicles and anything (V2X, X may represent anything), for example, the V2X may include: vehicle-to-vehicle (vehicle to vehicle, V2V) communication, vehicle-to-infrastructure (vehicle to infrastructure, V2I) communication, vehicle-to-pedestrian communication (vehicle to pedestrian, V2P) or vehicle-to-network (vehicle to network, V2N) communication, etc. By way of example, in fig. 1 shown below, the terminal device and the terminal device may communicate via D2D technology, M2M technology, V2X technology, or the like.

Referring to fig. 1, fig. 1 is a schematic diagram of a communication system according to an embodiment of the present application.

As shown in fig. 1, the communication system may include at least one access network device and at least one terminal device.

The descriptions of the access network device and the terminal device are respectively as follows:

by way of example, the access network device may be a next generation node B (next generation node B, gNB), a next generation evolved base station (next generation evolved nodeB, ng-eNB), or an access network device in future 6G communications, etc. The access network device may be any device having a wireless transceiver function including, but not limited to, the base station shown above. The base station may also be a base station in a future communication system, such as a sixth generation communication system. Alternatively, the access network device may be an access node, a wireless relay node, a wireless backhaul node, etc. in a wireless local area network (wireless fidelity, wiFi) system. Alternatively, the access network device may be a radio controller in the context of a cloud radio access network (cloud radio access network, CRAN). Alternatively, the access network device may be a wearable device or an in-vehicle device, etc. Alternatively, the access network device may also be a small station, a transmission receiving node (transmission reception point, TRP) (or may also be referred to as a transmission point), etc. It will be appreciated that the access network device may also be a base station in a future evolved public land mobile network (public land mobile network, PLMN), or the like.

In some deployments, a base station (e.g., gNB) may be composed of a Centralized Unit (CU) and a Distributed Unit (DU). Namely, the functions of the base stations in the access network are split, part of the functions of the base stations are deployed on one CU, and the rest of the functions are deployed on DUs. And a plurality of DUs share one CU, so that the cost can be saved, and the network expansion is easy. In other deployments of base stations, CUs may also be divided into CU-Control Plane (CP) and CU-User Plane (UP), etc. In yet other deployments of base stations, the base stations may also be open radio access network (open radio access network, ora) architecture, etc., the application is not limited to a particular type of base station.

For convenience of description, the method referred to in the present application will be described below by taking an access network device as an example of a base station.

The terminal device may also be referred to as a User Equipment (UE), a terminal, etc., for example. The terminal equipment is equipment with a wireless receiving and transmitting function, can be deployed on land, and comprises indoor or outdoor, handheld, wearable or vehicle-mounted; the device can also be deployed on the water surface, such as a ship, etc.; but may also be deployed in the air, for example on an aircraft, balloon or satellite, etc. The terminal device may be a mobile phone, a tablet (Pad), a computer with a wireless transceiving function, a Virtual Reality (VR) terminal device, an augmented reality (augmented reality, AR) terminal device, a wireless terminal in industrial control (industrial control), a wireless terminal in unmanned driving (self driving), a wireless terminal in remote medical (remote medium), a wireless terminal in smart grid (smart grid), a wireless terminal in transportation security (transportation safety), a wireless terminal in smart city (smart city), a wireless terminal in smart home (smart home), or the like. It is understood that the terminal device may also be a terminal device in a future 6G network or a terminal device in a future evolved PLMN, etc.

It can be understood that the terminal device shown in the application may include not only a vehicle (such as a whole vehicle) in the internet of vehicles, but also a vehicle-mounted device or a vehicle-mounted terminal in the internet of vehicles, and the specific form of the terminal device when applied to the internet of vehicles is not limited in the application.

For convenience of description, a method related to the present application will be described below by taking a terminal device as an example of UE.

As shown in fig. 1, the communication system may further comprise at least one core network device, and the description of the core network device is as follows:

the core network device comprises services such as user access control, mobility management, session management, user security authentication, charging and the like. It is composed of a plurality of functional units, and can be divided into functional entities of a control plane and a data plane. The access and mobile management unit (access and mobility management function, AMF) is responsible for user access management, security authentication and mobility management. The location management unit (location management function, LMF) is responsible for managing and controlling the location service request of the target terminal, and processing the location related information. The user plane unit (user plane function, UPF) is responsible for managing the functions of user plane data transmission, traffic statistics, etc.

In the communication system shown in fig. 1, one core network device, two base stations, and eight UEs are included, such as the core network device, base station 1, and base station 2 in fig. 1, and UEs 1 to 8. In this communication system, the base station 1 may transmit downlink signals such as configuration information and downlink control information (downlink control information, DCI) to the UEs 1 to 6, and the UEs 1 to 6 may transmit uplink signals such as SRS and physical uplink shared channel (physical uplink shared channel, PUSCH) to the base station 1. Base station 1 may also transmit downlink signals to UEs 7 to 8 through base station 2, and UEs 7 to 8 may transmit uplink signals to base station 1 through base station 2. The base station 2 may transmit downlink signals such as configuration information and DCI to the UEs 7 to 8, and the UEs 7 to 8 may transmit uplink signals such as SRS and PUSCH to the base station 2. It will be appreciated that reference may be made to the above description for the manner of communication between UEs, and this is not described in detail herein.

It should be appreciated that fig. 1 illustrates schematically one core network device, two base stations and eight UEs, and communication links between the communication devices. Alternatively, the communication system may include a plurality of base stations, and each base station may include other numbers of UEs, such as more or fewer UEs, within the coverage area, which is not limited in this application.

Each of the above-described communication apparatuses, such as the core network apparatus, the base station 1 and the base station 2, and the UEs 1 to 8 in fig. 1, may be configured with a plurality of antennas. The plurality of antennas may include at least one transmitting antenna for transmitting signals, at least one receiving antenna for receiving signals, and the like, and the specific structure of each communication device is not limited in the embodiments of the present application. Optionally, the communication system may further include a network controller, a mobility management entity, and other network entities, where embodiments of the present application are not limited.

It will be appreciated that the communication system diagram shown in fig. 1 is merely an example, and reference may be made to related standards or protocols, etc. for other forms of communication system diagrams, which are not described in detail herein.

Various embodiments shown below may be applied to the communication system shown in fig. 1, and may also be applied to other forms of communication systems, which will not be described in detail below.

The application provides a communication method which is applied to the technical field of communication, such as SDT and communication of broadcast service and multicast session under the inactive state of UE. To more clearly describe the solution of the present application, some knowledge about the communication of SDT and broadcast services, multicast sessions is introduced below.

Referring to fig. 2, fig. 2 is a schematic diagram of switching states of a terminal device according to an embodiment of the present application.

As shown in fig. 2, a radio resource control (radio resource control, RRC) state and a transition procedure between states. In the 5G New Radio (NR), the UE has three RRC states: rrc_inactive, rrc_connected, and rrc_idle. The method comprises the steps that RRC connection is established between a UE and a base station in an RRC connection state, when data transmission does not exist, the base station can release the UE to an RRC idle state, and the RRC connection is not established between the base station and the UE in the RRC idle state; or the base station releases the UE to the RRC inactive state, suspends (suspend) the RRC connection, and the RRC inactive state base station maintains the UE context information. The benefit of the NR introducing the RRC inactive state is that the RRC connection can be restored more quickly in the RRC inactive state than in the RRC idle state, since the base station still retains the UE context, and the delay can be reduced when traffic arrives.

The transition relationship between rrc_inactive (radio resource control-INACTIVE state) and rrc_connected (radio resource control-CONNECTED state) and rrc_idle (radio resource control-IDLE state) is shown in fig. 2.

Rrc_inactive can only be changed from rrc_connected to RRC release by means of an RRC release message, and when a UE is released from rrc_connected to rrc_inactive, the base station allocates an identity I-RNTI (INACTIVE radio network temporary identity) to the UE and stores the context of the UE with this identity, which is also called the last service gNB (last serving gNB) of the UE, sometimes denoted anchor gNB (anchor gNB).

When the UE requests to resume the previously suspended RRC connection or performs a radio notification area (radio notification area, RNA) update, the UE sends an rrcruumerequest message to the current serving base station, where the rrcruumerequest message structure includes a resume reason value, where the resume reason value is used to indicate a resume reason for the rrcruumerequest message to request for resuming, and the rrcruumerequest message structure further includes an i_rnti identifier, and the current serving base station retrieves a context of the UE according to the i_rnti identifier to the last serving gNB.

Referring to fig. 3, fig. 3 is a schematic RRC connection recovery flow diagram of a terminal device according to an embodiment of the present application. The steps of fig. 3 are described below:

s301: the UE sends an RRC connection recovery request rrcresemerequst to the current serving base station (gNB), which contains the I-RNTI allocated by the last serving base station (last serving gNB) for the UE.

S302: the gNB receives the RRCResumeRequst and, based on the gNB identity contained in the I-RNTI, may find the last serving gNB and request it to provide the context of the UE.

Specifically, the gNB sends a context acquisition request Retrieve UE context request message to the corresponding last serving gNB.

S303: the last serving gNB provides the context of the UE to the gNB.

Specifically, the last serving gNB sends a context acquisition response Retrieve UE context response message to the gNB, where the context acquisition response message includes the UE's context.

S304/S305: the gNB and the UE complete the recovery of the RRC connection, and can transmit user data in case of obtaining the grant.

S306: if the Downlink (DL) user data buffered in the last serving gNB is required to be lossless, the gNB needs to provide a forwarding address.

S307/S308: the gNB performs path switching.

S309: the gNB triggers the resource release of the UE at the last serving gNB.

It should be noted that, when the UE context cannot be retrieved, the gNB may send an RRCSetup message to the UE, and reestablish the RRC connection; or the gNB may send the RRCReject message directly to the UE for rejecting the UE's setup request.

Because of the mobility of the UE, when the UE is in RRC idle state, the network needs a Core Network (CN) to issue a paging message (CN-initiated paging) for all cells under all Tracking Areas (TAs) in a tracking area identity (tracking area identity, TAI) list. It can be seen that with this level of terminal tracking, a high paging message transmission overhead is incurred since most paging messages are issued in cells where the UE is not located. To save transmission overhead, for UEs in RRC inactive state, the concept of "(RAN-based Notification Area, RNA)" is introduced that is smaller than the TA range (one TA range may include multiple RNAs, one RNA may include multiple cells), the RNAs are managed by a gNB, and the gNB may send a paging message (RAN-initiated paging) to the cells within the RNA range. For RAN paging, when the last serving gNB receives downlink data from the UPF or downlink signaling from the AMF, the UE is paged on a cell in the RNA region, and if the cell in the RNA region includes a neighbor gNB(s), the last serving gNB delivers the RAN paging to the neighbor gNB(s) through the Xn interface, and the neighbor gNB(s) pages the UE in its cell.

In the non-active state of RRC, the terminal device can directly perform small data transmission (small data transmission, SDT) for the data transmission with smaller data quantity and infrequent data transmission without switching to the RRC connection state for transmission, thereby reducing the power consumption and signaling overhead caused by frequent RRC state switching due to the small data transmission requirement and realizing the purpose of reducing the power consumption of UE. Typical small and infrequent data transmissions include, but are not limited to: instant messaging service, push notifications of various applications, periodic positioning information of wearable devices, periodic data transmission of industrial sensors, and the like.

Wherein the transmission of the SDT may include:

(1) Small data transmission over random access channel (random access channel, RACH): the UE sends SDT uplink data (UL data) and rrcresemerequest to the gNB in msg3 (corresponding to four-step RACH) or msgA (corresponding to two-step RACH);

(2) Small data transfer through Configuration Grant (CG) resources: and the UE sends the SDT UL data and the RRCResumeRequest to the gNB through CG resources configured in the RRCRelease message by the gNB.

The transmission of SDT includes two network architectures:

architecture one: SDT (SDT with UE context relocation) with UE context relocation;

And a second architecture: SDT (SDT without UE context relocation) without UE context relocation.

Since the UE moves in an inactive state, if the gcb accessed by the UE is not a last serving gcb, UL SDT data/signaling is buffered in the current serving base station (reception gcb), and then the reception gcb triggers the XnAP to retrieve the UE context (XnAP Retrieve UE Context) procedure. The receiving gNB indicates to the last serving gNB that there is an SDT, and the last serving gNB decides whether to relocate the UE context.

Architecture one: if the last serving gNB decides to relocate the complete UE context, the complete UE context is sent to the receiving gNB, which is called the SDT with UE context relocation. In this case, upstream SDT data is sent from the receiving gNB to the UPF. After the SDT transmission is finished, the receiving gNB can send RRCRelease information to the UE to release the UE to return to the RRC inactive state or the RRC idle state; if downlink non-SDT data or signaling arrives in the SDT process or uplink non-SDT data arrives, the receiving gNB can send an RRCResume message to the UE to return the UE to the RRC connected state.

And a second architecture: if the last serving gNB decides not to relocate the complete UE context, then a partial UE context is sent to the receiving gNB (partial UE context), which contains SDT radio Link control (radio link control, RLC) context information required for processing the SDT, referred to as a UE context relocation free SDT. The Last serving gNB maintains a data convergence protocol (packet data convergence protocol, PDCP) entity, while the receiving gNB establishes SDT-related RLC contexts and establishes UL/DL GTP-U tunnels required for the SDT, forwards SDT data and/or signaling to the Last serving gNB, and then is sent to the core network CN by the Last serving gNB. After the SDT process is completed (the receiving gNB detects that there are no more packets to transmit), the receiving gNB sends a search context acknowledgement RETRIEVE UE CONTEXT CONFIRM message informing the last serving gNB, and the last serving gNB controls whether to terminate the SDT process, if so, sends a search context failure RETRIEVE UE CONTEXT FAILURE containing the encapsulated RRCRelease message to the receiving gNB, which releases part of the UE context (partial UE context), and sends the RRCRelease message to the UE. If downlink non-SDT data or signaling arrives or uplink non-SDT data arrives in the SDT process, the last serving gNB releases the UE to the RRC inactive state, otherwise releases the UE to the RRC idle state. It can be appreciated that when the receiving gNB has no completed UE context, the gNB releases the UE to the inactive state and can page the UE again to enter the RRC connected state for transmission.

Broadcast communication: refers to a communication service mode in which a network device simultaneously provides the same specific content data to all terminal devices in a certain geographical area. In NR R17, a terminal device supporting NR MBS broadcasting may acquire a broadcast communication service in an RRC connected state, an RRC idle state, and an RRC inactive state.

If the gNB broadcasts SIB21 on a cell (SIB 21 contains a mapping relationship between frequencies and broadcast services provided in an area, the UE may determine which broadcast services are provided in the area according to SIB21 on which frequency to preferentially select a cell capable of providing a frequency of the broadcast service that the UE wants to receive for camping on), on which cell the UE may report MBS interest indication information (MBS Interest Indication, MII) to the gNB in an RRC connected state, indicating frequency information (frequency point ARFCN of broadcasting) that the UE is interested in receiving the broadcast, an identification (TMGI) of a broadcast session, priority of broadcasting compared to unicast, and so on. The gNB acquires the broadcasting service which is being received or is interested in being received by the UE through the MII, and further performs proper scheduling according to the UE capability, so that the capability of simultaneously scheduled broadcasting and unicast does not exceed the capability of the UE.

For example, if the UE supports broadcast (UE reporting MII may indicate that the UE supports broadcast), the UE must opt to support unicast physical downlink shared channel (physical downlink shared channel, PDSCH) and broadcast PDSCH by TDM reception in different time slots (it may be understood that unicast data blocks and broadcast data blocks are received in different time slots). In addition, in the UE capability information, the UE may report whether TDM reception of unicast PDSCH and broadcast PDSCH in the same time slot is supported, and FDM reception between unicast and broadcast in the same time slot is supported. If the UE does not support simultaneous reception of broadcast and unicast in one slot, the base station needs to schedule unicast and broadcast data time-division in different slots.

Multicast (or multicast) communication: refers to the same service and the same specific content data being provided to a group of dedicated UEs at the same time (i.e. not all UEs in the multicast service area are authorized to receive the data). Multicast traffic is delivered to the UE through a multicast session (multicast session). In Rel-17, the UE can only receive data of a multicast session in RRC connected state. If the UE joining the multicast session is in RRC connected state, when the multicast session is active, the gNB sends RRCRECONfigure message with multicast session related MBS configuration to the UE. When (temporarily) there is no data for the multicast session to send to the UE, the gNB may move the UE to RRC idle state or inactive state. When the multicast session is activated by the CN or the gNB has multicast session data to transmit, the gNB supporting the MBS uses a group notification (group notification) mechanism to notify the UE in RRC idle state or inactive state that has multicast session data to issue (CN controls activation/deactivation of multicast, CN may notify gNB that multicast is activated after CN paging, trigger RAN paging, or trigger RAN paging after multicast session data arrives at gNB). After receiving the group notification, the UE reestablishes RRC connection with the gNB. The group notification is issued to the UE by a paging message, and the paging message for the group notification contains an MBS session ID (i.e. TMGI) for paging all UEs in RRC idle state and RRC inactive state that join an MBS multicast session. After receiving the paging message, the UE determines that the paging message contains the TMGI of the multicast session that the UE has joined, and then triggers RRC connection establishment or RRC connection restoration.

In the small data transmission (SDT without UE context relocation) scenario without UE context relocation, if the terminal device is still interested in receiving or is receiving the multicast broadcast service, the data transmission of the SDT and the broadcast multicast service scheduled by the network device corresponding to the serving cell may exceed the receiving capability of the terminal device, resulting in packet loss or error code, and affecting the service quality. Aiming at the technical problem that the data transmission of the SDT and the broadcast multicast service scheduled by the network equipment corresponding to the service cell in the communication process may exceed the receiving capability of the terminal equipment, so that packet loss or error code is caused.

Referring to fig. 4, fig. 4 is a flow chart of a communication method according to an embodiment of the present application. The communication method is applied to the technical field of communication, and comprises the following steps:

S401: the terminal device performs a small data transfer SDT with the first network device and the terminal device is interested in receiving or is receiving the first broadcast service from the first network device.

Wherein the terminal device is in an RRC inactive state, the terminal device in the RRC inactive state performs SDT with the first network device, and the terminal device is interested in receiving or is receiving the first broadcast service from the first network device. The broadcast service that the terminal device is interested in receiving in the present application may also refer to a broadcast service that the terminal device does not receive but is to receive.

It can be understood that the terminal device in the embodiment of the present application is a device carrying a processor for executing an instruction executed by a computer, which may be a handheld terminal (such as a mobile phone, a tablet computer, etc.), a vehicle-mounted terminal (such as a wireless terminal in an unmanned plane, etc.), or the like, and specifically may also be the terminal device in fig. 1 (including, but not limited to, any one of devices such as UE1 to UE 8) described above, which is configured to execute the communication method in the embodiment of the present application, so as to implement that the terminal device may receive data of SDT and multicast broadcast service in a small data transmission scenario without UE context relocation.

It can be understood that the first network device in the embodiment of the present application is a device on which a processor capable of executing a computer execution instruction is mounted, and may be an access network device, such as a base station, a transmission point TRP, or the like, or may be a server, specifically may be an access network device in fig. 1 (including but not limited to any device such as a base station 1 and a base station 2) for executing the communication method in the embodiment of the present application, so that the terminal device may receive data of the SDT and the multicast broadcast service in a small data transmission scenario without UE context relocation.

S402: the terminal equipment sends first information to the first network equipment, and correspondingly, the first network equipment receives the first information sent by the terminal equipment.

The first information may be sent by the terminal device to the first network device during SDT, for example, carried in a random access message 3 (msg 3) and sent through SRB1 or SRB2, where the random access message 3 may further include an RRC restoration request message rrcresmerequest.

The first information may also be information sent by the terminal device on an uplink resource dynamically scheduled by the first network device or on a resource of a configuration grant (configured grant) during SDT.

The first information includes information of a first broadcast service, which may specifically be multicast broadcast service (multicast broadcast service, MBS) interest indication information (MBS Interest Indication, MII) for indicating information of MBS broadcast services that the terminal device is interested in receiving or is receiving, such as frequency of MBS broadcast service, identification information of MBS broadcast service, priority information of MBS broadcast compared with unicast and MBS multicast reception, etc. The first information is used for the first network device to provide the first broadcast service to the terminal device during SDT with the terminal device.

According to the embodiment of the invention, under the condition that the terminal equipment is in an RRC inactive state and performs SDT with the first network equipment, and the terminal equipment receives the first broadcast service from the first network equipment, the first network equipment can know that the terminal equipment still receives the first broadcast service in the SDT process by reporting the first information to the first network equipment, so that the first network equipment can properly schedule the SDT and the first broadcast service, for example, the SDT data and the first broadcast service data are transmitted in a time slot time division multiplexing mode, or the SDT data and the first broadcast service data are transmitted in a time slot frequency division multiplexing mode, and the like, so that the terminal equipment can also receive the SDT and the broadcast service data in a small data transmission scene without a UE context, and error codes and/or packet loss caused by exceeding the receiving capacity of the terminal equipment in scheduling are avoided. The first network device is a network device corresponding to a serving cell where the terminal device resides in an RRC inactive state, and may also be a receiving gNB that performs SDT with the terminal device.

In the embodiment of the present application, the broadcast service may refer to an MBS broadcast service (broadcast service), and the multicast service may refer to an MBS multicast service (multicast service). The SDT includes data and/or signaling for downstream/upstream SDTs.

In one possible embodiment, the first network device transmits the SDT and the first broadcast service on different time slots, and the terminal device receives the SDT and the first broadcast service from the first network device on different time slots.

Among other things, SDT can be understood as downstream SDT data (DownLink SDT data). The reception of the SDT and the data of the first broadcast service on different time slots may be understood/replaced by the reception of a physical downlink shared channel (physical downlink shared channel, PDSCH) for transmitting the SDT data and a PDSCH or group common PDSCH (group common physical downlink shared channel, GC-PDSCH) for transmitting the data of the first broadcast service on different time slots.

After receiving the first information, the first network device knows that the terminal device is interested in receiving or is receiving the first broadcast service in the SDT process with the first network device, and the first network device sends the SDT data and the data of the first broadcast service by scheduling the SDT and the first broadcast service, for example, by an inter-slot time division multiplexing (inter-slot TDM) mode, or sends the SDT data and the data of the first broadcast service by an inter-slot frequency division multiplexing (inter-slot FDM) mode, and so on. For example, the SDT data may be sent to the terminal device in the time slot 1, and the first broadcast service data may be sent to the terminal device in the time slot 2, so that the terminal device may receive the SDT data and the first broadcast service data from the first network device in different time slots, so as to avoid error codes and/or packet loss caused by the scheduling exceeding the receiving capability of the terminal device.

According to the embodiment of the application, in the SDT (SDT without UE context relocation) scenario without UE context relocation, if the terminal device is interested in receiving or is receiving the first broadcast service from the first network device, the first network device (i.e. the network device corresponding to the serving cell, also referred to as the receiving gNB of the SDT) may learn information of the first broadcast service received by the terminal device, so that the SDT and the data of the first broadcast service are scheduled on different time slots, and the terminal device may receive the SDT and the data of the first broadcast service sent by the first network device on different time slots even if the terminal device does not have the capability of receiving unicast data and broadcast data on the same time slot.

It may be understood that, the terminal device sends the first information to the first network device, which may indicate that the terminal device supports receiving the MBS broadcast service, and the terminal device must optionally support time division multiplexing (inter-slot TDM) reception between PDSCH for transmitting unicast data and PDSCH/GC-PDSCH for transmitting MBS broadcast data, so that the first network device sends the SDT and the data of the first broadcast service according to time division multiplexing between timeslots, which may ensure that the terminal device can receive the first broadcast service in the SDT process, and avoid causing error codes and/or packet loss, thereby ensuring the service quality of the SDT and the MBS broadcast service. When the terminal device does not support receiving unicast data and MBS broadcast data in the same time slot, in the SDT scenario without context relocation, the first network device does not have UE capability information, if the first network device does not know that the terminal device is receiving the first broadcast service, when the first network device schedules/sends SDT data (SDT may be understood as a unicast transmission mode) and data of the first broadcast service in the same time slot, the terminal device may not receive the SDT and the broadcast data, or the terminal device may only receive one of the SDT and the broadcast data, which causes data error codes and/or packet loss, and affects service receiving quality. Therefore, by the scheme, the problem that the data transmission of the SDT and the broadcast multicast service scheduled by the network equipment corresponding to the service cell possibly exceeds the receiving capability of the terminal equipment, so that packet loss or error code is caused can be avoided.

In one possible embodiment, the terminal device sends the first information to the first network device if it is determined that a certain condition is met.

Exemplary one:

before the terminal equipment sends the first information to the first network equipment, the terminal equipment also receives the second information sent by the first network equipment and/or the third information sent by the second network equipment, and determines to send the first information to the first network equipment according to the second information and/or the third information.

The first information at this time includes information of a first broadcast service, which may be specifically an MII, information indicating MBS broadcast services that the terminal apparatus is interested in receiving or is receiving, such as frequencies of MBS broadcast services, identification information of MBS broadcast services, priority information of MBS broadcast compared to unicast and MBS multicast reception, and the like.

According to the embodiment of the application, under the condition that the terminal equipment is in an RRC inactive state and performs SDT with the first network equipment and the terminal equipment receives the first broadcast service from the first network equipment, the reporting of the first information can be determined according to the second information sent by the first network equipment, or the reporting of the first information can be determined according to the third information sent by the second network equipment, or the reporting of the first information can be determined according to the second information sent by the first network equipment and the third information sent by the second network equipment; it is also understood that the first network device controls whether the terminal device is allowed to report the first information by means of the transmitted second information and/or the second network device controls whether the terminal device is allowed to report the first information by means of the transmitted third information. The second information and the third information may be the same information or different information.

Exemplary two:

before the terminal equipment sends the first information to the first network equipment, the terminal equipment also receives fourth information sent by the first network equipment and/or fifth information sent by the second network equipment, and determines to send the first information to the first network equipment according to the fourth information and/or the fifth information.

The first information at this time includes temporary mobile group identity (temporary mobile group identity, TMGI) information of the first broadcast service.

According to the embodiment of the application, in the scenario that the terminal equipment is in the RRC inactive state and performs SDT with the first network equipment, and the terminal equipment receives the first broadcast service from the first network equipment, the terminal equipment can determine that the first information includes the TMGI information of the first broadcast service according to the fourth information sent by the first network equipment, or determine that the second information includes the TMGI information of the first broadcast service according to the fifth information sent by the second network equipment, or determine that the second information includes the TMGI information of the first broadcast service according to the fourth information sent by the first network equipment and the fifth information sent by the second network equipment. The fourth information and the fifth information may be the same information or different information.

In one possible embodiment, in the above-described first and second examples, the third information and/or the fifth information may be carried in an RRC release message.

For example, the third information and/or the fifth information may be one indication bit (for example, 1 bit) in the RRC release message, and the third information and the fifth information may be different information, indicated by two independent bits, or may be the same information, indicated by the same bit.

For example, when the third information and the fifth information are two independent information, the RRC release message includes the third information, or a bit position corresponding to the third information is 1, which indicates that the terminal device is allowed to report the first information (specifically, may be MII) or indicates that the terminal device is allowed to report the first information in an RRC inactive state, or indicates that the terminal device is allowed to report the first information in an SDT process. The reporting permission may also be understood as that the second network device supports receiving the first information reported by the terminal device from the RRC inactive state, or the first information reported by the terminal device in the SDT process.

For example, when the third information and the fifth information are two independent information, the RRC release message does not include the third information, or a bit position corresponding to the third information is 0, which indicates that the terminal device is not allowed to report/the second network device does not support receiving the first information (specifically, may be MII), or indicates that the terminal device that does not allow/support receiving the RRC inactive state does not report the first information, or indicates that the receiving terminal device is not allowed/supported to report the first information in the SDT process.

Similarly, referring to the third information, in the setting and meaning of the fifth information, when the RRC release message includes the fifth information or the bit position corresponding to the fifth information is 1, it indicates that the first information that the terminal device is allowed to report includes the TMGI information of the broadcast service/the first information that the second network device supports to receive the broadcast service is included in the first information that the terminal device is allowed to report, or indicates that the first information that the terminal device that is allowed to receive the RRC inactivity state includes the TMGI information of the broadcast service, or indicates that the terminal device is allowed to receive the TMGI information that the terminal device is allowed to receive the broadcast service in the first information that the terminal device is reported in the SDT process.

For example, when the fifth information and the third information are the same information, or the fifth information and the third information are the same indication bit/bit, when the RRC release message includes the information, or the bit/indication position is 1, it indicates that the terminal device is allowed to report/support the second network device to receive the first information (may specifically be an MII), and the first information may include TMGI information of the broadcast service.

For example, when the fifth information and the third information are the same information, or the fifth information and the third information are the same indication bit/bit, when the RRC release message does not include the information, or the bit/indication position is 0, the first information (specifically, may be MII) indicating that the terminal device is not allowed to report TMGI information including the broadcast service is indicated. Other meaning examples refer to the description of the third information/the fifth information above, and are not repeated here.

Through the embodiment of the application, the second network device can control the reporting of the first information by the terminal device through the third information and/or the fifth information, and has better backward compatibility. For example, for an old version of network equipment, if the terminal equipment which does not expect the non-active dynamic state of the RRC reports the first information, or if the terminal equipment does not expect the first information reported in the SDT process, the RRC release message may not include the third information and/or the fifth information, and then the terminal equipment may not report the first information; for the updated network device capable of supporting the RRC inactive state terminal device to report the first information/the terminal device reports the first information in the SDT process, the RRC release message may include third information and/or fifth information.

In one possible embodiment, in the above-described exemplary one, exemplary two, the second information, and/or the third information, and/or the fourth information, and/or the fifth information may include system information (System Information, SI); alternatively, the second information, and/or the third information, and/or the fourth information, and/or the fifth information may be transmitted in the form of a system information block (System Information Bloack, SIB).

Example a:

the second information and/or the third information may include first system information; alternatively, the second information and/or the third information may be transmitted in the form of a first system information block.

Wherein, the first system information is used to indicate the mapping relation between the multicast broadcast service and the frequency, for example, the first system information may correspond to a system information block SIB21; alternatively, the first system information may be used to indicate configuration parameters of a multicast broadcast service control channel (MBS control channel, MCCH), for example, may correspond to a system information block SIB20.

Example B:

the fourth information and/or the fifth information may include second system information; alternatively, the fourth information and/or the fifth information may be transmitted in the form of a second system information block.

Wherein, the second system information is used for indicating the mapping relation between the multicast broadcast service and the frequency, for example, the second system information can correspond to a system information block SIB21; alternatively, the second system information is used to indicate configuration parameters of a multicast broadcast service control channel (MBS control channel, MCCH), for example, may correspond to the system information block SIB20.

It will be appreciated that the second information, and/or the third information, and/or the fourth information, and/or the fifth information shown in the above embodiments may be provided in a variety of possible combinations to the terminal device for controlling the transmission of the first information.

It will be appreciated that before the terminal device sends the first information to the first network device, the terminal device determines that the conditions described in at least one of the following ways are met:

mode one:

the first serving cell associated with the second network device provides a system information block SIB21, the terminal device determines that the first information can be sent to the first network device.

The first serving cell associated with the second network device provides a system information block SIB21, and the serving cell (associated with the first network device) where the terminal device is currently camping provides the system information block SIB20, the terminal device determines that the first information can be sent to the first network device, and the first information can include TMGI information of the broadcast service.

In this embodiment of the present application, the first serving cell associated with the second network device provides SIB21 may be understood as a first serving cell that can provide SIB21, and the first serving cell may be a serving cell in which the terminal device has been camping. In one possible implementation manner, the terminal device stores a cell list in which SIB21 is broadcast, and determines whether the first serving cell is in the cell list according to the cell list, and if the first serving cell is in the cell list, the first serving cell can provide SIB21.

In the embodiment of the present application, the serving cell providing SIB20 may be understood as including scheduling information of SIB20 in SIB1 broadcasted by the serving cell, or as that the serving cell can provide SIB20. The present application does not limit whether the serving cell is broadcasting SIB20, either the serving cell is broadcasting SIB20 or not broadcasting SIB20.

Mode two:

the first serving cell with which the second network device is associated provides SIB21 and the serving cell (associated with the first network device) in which the terminal device is currently camping provides SIB21, the terminal device determines that the first information can be sent to the first network device.

The first serving cell associated with the second network device provides SIB21, and the serving cell (associated with the first network device) in which the terminal device is currently camping provides SIB21, and the serving cell in which the terminal device is currently camping provides SIB20, the terminal device determines that the first information can be sent to the first network device, and the first information can include TMGI information of the broadcast service.

The first serving cell associated with the second network device provides an understanding of SIB21 and possible embodiments are as described in the first embodiment, and are not described herein.

Mode three:

the received RRC release message from the second network device contains the third information and the serving cell (associated with the first network device) where the terminal device is currently camping provides SIB21, the terminal device determines that the first information can be sent to the first network device.

The received RRC release message from the second network device includes third information, and the serving cell (associated with the first network device) where the terminal device currently resides provides SIB21, and when the received RRC release message from the second network device includes fifth information, the terminal device determines that the first information may be sent to the first network device, and the first information may include TMGI information of the broadcast service, where the third information and the fifth information are different information.

Mode four:

the third information and the fifth information are the same information, the RRC release message received from the second network device contains the third information (or the fifth information), and the serving cell (associated with the first network device) where the terminal device is currently camping provides SIB21, then the terminal device determines that the first information can be sent to the first network device.

The third information and the fifth information are the same information, the RRC release message received from the second network device includes the third information (or the fifth information), and the serving cell (associated with the first network device) where the terminal device is currently camping provides SIB21, and the serving cell where the terminal device is currently camping provides SIB20, then the terminal device determines that the first information can be sent to the first network device, and the first information can include TMGI information of the broadcast service.

Mode five:

the third information and the fifth information are the same information, the RRC release message received from the second network device includes the third information (or the fifth information), and the first serving cell associated with the second network device provides SIB21 (which may be implemented in a manner described above and not described herein), and the serving cell (associated with the first network device) where the terminal device currently resides provides SIB21, so that the terminal device determines that the first information may be sent to the first network device.

The third information and the fifth information are the same information, the RRC release message received from the second network device includes the third information (or the fifth information), and the first serving cell associated with the second network device provides SIB21 (which may be implemented in a manner described above and not described herein), and the serving cell currently residing in the terminal device (associated with the first network device) provides SIB21, and the serving cell currently residing in the terminal device provides SIB20, then the terminal device determines that the first information may be sent to the first network device, and the first information may include TMGI information of the broadcast service.

Mode six:

the serving cell (associated with the first network device) in which the terminal device is currently camping provides SIB21, the terminal device determines that the first information may be sent to the first network device.

The serving cell (associated with the first network device) where the terminal device currently resides provides SIB21, and when the terminal device receives the RRC release message from the second network device, the terminal device determines that the first information may be sent to the first network device, where the first information may include TMGI information of the broadcast service, and the third information and the fifth information are the same information.

It should be understood that the above six ways are merely illustrative of possible combinations of the second information, and/or the third information, and/or the fourth information, and/or the fifth information, and should not be construed as limiting the embodiments herein. Other combination manners after reasonable deformation may be used to provide the terminal device with control of reporting the first information or reporting the TMGI in the first information, which is not limited in the embodiment of the present application.

It should be understood that the above-mentioned second network device, which is a device on which a processor for executing computer-executable instructions is mounted, may be an access network device, such as a base station, a transmission point TRP, or may be a server, and specifically may be an access network device (including but not limited to any device such as a base station 1 and a base station 2) in fig. 1, which is configured to execute the communication method in the embodiment of the present application, so as to implement that the terminal device may receive the data of the SDT and the multicast broadcast service in a small data transmission scenario without UE context relocation. Wherein the second network device is a network device connecting the terminal device and the core network device, it is to be understood that the connection between the terminal device and the core network device may be a connection of a non-access stratum (non access stratum, NAS).

Referring to fig. 5, fig. 5 is a flow chart of another communication method according to an embodiment of the present application. It will be appreciated that steps S503 to S508 in the embodiments of the present application may be regarded as a reasonable modification or addition to the embodiment of fig. 4 described above; alternatively, it is understood that the communication method in the embodiment of the present application may also be regarded as an embodiment that can be executed separately, which is not limited in this application. The communication method provided by the embodiment of the application is applied to the technical field of communication, and comprises the following steps:

s501: the terminal device performs a small data transfer SDT with the first network device and the terminal device is interested in receiving or is receiving the first broadcast service from the first network device.

Consistent with the above step S401, a detailed description thereof will be omitted.

S502: the terminal equipment sends first information to the first network equipment, and correspondingly, the first network equipment receives the first information sent by the terminal equipment.

Consistent with the above step S402, a detailed description thereof will be omitted.

It may be understood that the first network device and the second network device in the embodiments of the present application are devices on which a processor capable of executing computer execution instructions is mounted, and may be access network devices, such as a base station, a transmission point TRP, or the like, or may also be a server, specifically may be the access network device in fig. 1 (including, but not limited to, any device of the base station 1 and the base station 2) described above, which is configured to execute the communication method in the embodiments of the present application, so as to implement that the terminal device may receive data of SDT and multicast broadcast service in a small data transmission scenario without UE context relocation.

S503: the first network device sends a first request message to the second network device, and the second network device receives the first request message sent by the first network device.

The first network device sends a first request message to the second network device, wherein the first request message is used for requesting to acquire the context information of the terminal device for SDT.

S504: the second network device sends the UE context information to the first network device, and correspondingly, the first network device receives the UE context information sent by the second network device.

The second network device sends partial context information of the terminal device to the first network device in response to the first request message, and correspondingly, the first network device receives the partial context information of the terminal device sent by the second network device in response to the first request message.

Optionally, the part of the context information includes seventh information for indicating a second broadcast service received by the terminal device.

Optionally, the second network device determines that the terminal device does not support receiving the data of the SDT and MBS broadcast services in the same time slot, and the second network device includes seventh information in the context information of the terminal device portion; the second network device determines that the terminal device supports receiving data of the SDT and MBS broadcast services in the same time slot, and the second network device does not include seventh information in the terminal device part context information.

According to the embodiment of the application, under the condition that the first network device performs SDT with the terminal device in RRC inactive state and the first network device provides the second broadcast service for the terminal device in RRC inactive state, the first network device can know that the terminal device is interested in receiving or receiving the second broadcast service in the SDT process by sending the first request message to the second network device and receiving the seventh information in part of the context information of the terminal device provided by the second network device, so that the first network device can perform proper scheduling on the SDT and the second broadcast service, for example, send SDT data and data of the first broadcast service in a time slot time division multiplexing mode, or send SDT data and data of the first broadcast service in a time slot frequency division multiplexing mode, and the like, so that the terminal device can also receive the SDT and the data of the second broadcast service in a small data transmission scene without UE context relocation, and error codes and/or packet loss caused by scheduling exceeding the receiving capability of the terminal device are avoided.

S505: the first network device sends first information to the second network device, and the second network device receives the first information sent by the first network device.

As can be seen from the above step S502, the first network device receives the first information sent by the terminal device.

In this embodiment, the first network device sends first information to the second network device.

The second network device is a network device that connects the terminal device and the core network device, where it is understood that the connection between the terminal device and the core network device may be a connection of a non-access stratum (non access stratum, NAS), or it is understood that the second network device is a network device that has a NGAP (NG Application Protocol) association relationship between the terminal device and the core network device.

It may be appreciated that the first information may be an RRC message, and after the first network device receives the first information sent by the terminal device, the first network device forwards the first information (may specifically be an RLC packet carrying the first information, such as an RLC SDU or PDCP PDU) to the second network device, because the first network device does not have complete context information of the terminal device, such as the first network device only has RLC context of the terminal device, but does not have PDCP and RRC related information (such as PDCP context) of the terminal device. The second network device is provided with complete context information of the terminal device, for example, the second network device is provided with PDCP and RRC related information (for example, PDCP context) of the terminal device, so that the second network device may interpret the first information forwarded by the first network device based on the complete context information of the terminal device, obtain sixth information, and send the sixth information to the first network device, where the sixth information is used to indicate the first broadcast service. The sixth information is obtained based on the first information, and the sixth information and the first information may be the same information, for example, the sixth information is the first information that the second network device sends to the first network device through an interface (for example, an Xn interface) between the network devices; the sixth information and the first information may also be different information, e.g. the sixth information contains part or all of the first information, determined/generated by the second network device, sent to the first network device via an interface between the network devices (e.g. an Xn interface).

S506: the second network device sends sixth information to the first network device, and correspondingly, the first network device receives the sixth information sent by the second network device.

As can be seen from the above step S505, the second network device may decode the first information sent by the first network device to obtain sixth information, where the sixth information is used to indicate the first broadcast service.

In this step, the second network device sends sixth information to the first network device, and correspondingly, the first network device receives the sixth information sent by the second network device. The first network device can know that the terminal device is still receiving the first broadcast service in the SDT process by receiving the sixth information sent by the second network device, so that the first network device can perform corresponding scheduling on the SDT and the first broadcast service, and the terminal device can also receive the data of the SDT and the broadcast service in a small data transmission scene without UE context relocation.

Optionally, if the second network device determines that the terminal device does not support receiving the data of the SDT and MBS broadcast services in the same time slot, the second network device sends sixth information to the first network device; the second network device determines that the terminal device supports receiving the data of the SDT and MBS broadcast services in the same time slot, and the second network device does not transmit the sixth information.

It should be understood that the execution sequence of steps S503 and S504 and steps S505 and S506 is not specifically limited in this embodiment, and the execution sequence thereof is based on the actual implementation sequence of the solution.

In one possible embodiment, the first network device ignores the seventh information if the sixth information is received.

It will be appreciated that in the event that the first network device receives the sixth information, the first network device will schedule the SDT and the corresponding first broadcast service in accordance with the sixth information, whether or not the first network device received the seventh information. When the first network device receives the broadcast service indicated in the seventh information and the broadcast service indicated in the sixth information, the broadcast service indicated in the sixth information is different, and the broadcast service 1, the broadcast service 2, and the broadcast service 3 are received by the terminal device in the seventh information, and the broadcast service 2 and the broadcast service 4 are received by the terminal device in the sixth information, the first network device considers that the broadcast service that the terminal device is interested in receiving or is receiving is the broadcast service 2 and the broadcast service 4, and the terminal device is not receiving the broadcast service 1 and the broadcast service 3.

In a possible embodiment, when the first network device does not receive the sixth information and receives the seventh information, the first network device schedules the SDT and the corresponding second broadcast service according to the seventh information, so that the terminal device can also receive the data of the SDT and the second broadcast service in a small data transmission scenario without UE context relocation, and error codes and/or packet loss caused by the fact that the scheduling exceeds the receiving capability of the terminal device are avoided.

S507: the second network device sends eighth information and/or ninth information to the first network device, and correspondingly, the first network device receives the eighth information and/or the ninth information sent by the second network device.

Wherein the eighth information is used for indicating that the terminal device supports or does not support Frequency Division Multiplexing (FDM) reception of one or more unicast data and one or more broadcast data in the same time slot, in other words, the eighth information is used for indicating that the terminal device supports or does not support Frequency Division Multiplexing (FDM) reception of M unicast data and N broadcast data in the same time slot, where M and N are integers greater than or equal to 1.

The ninth information is used to indicate that the terminal device supports or does not support Time Division Multiplexing (TDM) reception of one or more unicast data and one or more broadcast data in the same time slot, in other words, the ninth information is used to indicate that the terminal device supports or does not support Time Division Multiplexing (TDM) reception of P unicast data and Q broadcast data in the same time slot, where P and Q are integers greater than or equal to 1.

Optionally, the eighth information is further used to instruct the terminal device to support or not support, on the first frequency band or the carrier of the first frequency band, reception of M unicast data and N broadcast data in a frequency division multiplexing FDM in the same time slot, where M and N are integers greater than or equal to 1; the eighth information includes an identification of the first frequency band;

Optionally, the ninth information is further used to instruct the terminal device to support or not support time division multiplexing TDM reception of P unicast data and Q broadcast data in the same time slot on the second frequency band or a carrier of the second frequency band, where P and Q are integers greater than or equal to 1; the ninth information comprises an identification of the second frequency band; the first frequency band and the second frequency band may be the same frequency band or different frequency bands.

The second network device sends the eighth information and/or the ninth information to the first network device, so that the first network device can learn the capability of the terminal device to receive the SDT data and the broadcast data in parallel, and therefore schedule the data in a more flexible manner. For example, when the terminal device supports reception of 1 unicast PDSCH and 1 broadcast GC-PDSCH in a frequency division multiplexing manner in the same slot, the first network device may transmit 1 unicast PDSCH and 1 broadcast GC-PDSCH in a frequency division multiplexing manner in the same slot. For another example, when the terminal device supports reception of 1 unicast PDSCH and 1 broadcast GC-PDSCH in a time division multiplexed manner within the same time slot, the first network device may transmit 1 unicast PDSCH and 1 broadcast GC-PDSCH in a time division multiplexed manner within the same time slot.

It should be understood that, in the embodiment of the present application, the execution sequence of the step S507, the steps S503 and S504, and the steps S505 and S506 is not specifically limited, and the execution sequence thereof is based on the actual implementation sequence of the solution.

S508: the first network device provides the SDT and the first broadcast service to the terminal device, and the terminal device receives the SDT and the first broadcast service from the first network device, respectively.

The first network device may send the SDT data and the data of the first broadcast service by scheduling the SDT and the first broadcast service, for example, by time division multiplexing between time slots, or send the SDT data and the data of the first broadcast service by frequency division multiplexing between time slots, etc., so that the terminal device may receive the SDT and the data of the first broadcast service from the first network device on different time slots.

According to the embodiment of the application, the network equipment corresponding to the service cell can acquire the multicast and broadcast service information which the terminal equipment is interested in receiving or is receiving under the small data transmission scene without the UE context relocation so as to reasonably schedule and transmit data, so that the terminal equipment can receive the SDT and the data of the multicast and broadcast service.

Referring to fig. 6, fig. 6 is a flow chart of another communication method according to an embodiment of the present application. It will be appreciated that embodiments of the present application may be regarded as a reasonable variation or addition to the embodiments of fig. 4, 5 described above; alternatively, it is understood that the communication method in the embodiment of the present application may also be regarded as an embodiment that can be executed separately, which is not limited in this application. The communication method provided by the embodiment of the application is applied to the technical field of communication, and comprises the following steps:

s601: the terminal device performs a small data transfer SDT with the first network device and the terminal device joins the first multicast session from the first network device.

The terminal equipment is in an RRC inactive state, the terminal equipment in the RRC inactive state performs SDT with the first network equipment, and the terminal equipment joins the first multicast session from the first network equipment.

It is understood that the terminal device joins the first multicast session from the first network device, it is understood that the terminal device joins the first multicast service and is able to receive the first multicast session from the first network device. Optionally, the terminal device is receiving a first multicast session from a first network device.

S602: the first network device sends a second request message to the second network device, and correspondingly, the second network device receives the second request message sent by the first network device.

The first network device sends a second request message to the second network device, wherein the second request message is used for requesting to acquire the context information of the terminal device for SDT.

It is to be understood that, before step S602, the first network device may or may not be providing the first multicast session to the terminal device, which is not limited by the embodiment of the present application.

S603: the second network device sends the UE context information to the first network device, and correspondingly, the first network device receives the UE context information sent by the second network device.

The second network device transmits partial context information (UE context information) of the terminal device to the first network device in response to the second request message, and correspondingly, the first network device receives partial context information (UE context information) of the terminal device transmitted by the second network device in response to the second request message.

The UE context information includes tenth information, where the tenth information is used to indicate information of the first multicast session that the terminal device joins, and the first network device may send data of the first multicast session to the terminal device according to the tenth information.

Optionally, the second network device determines that the first multicast session is active (activated) before sending the first information. The first multicast session indicated by the tenth information is an active multicast session.

Optionally, the second network device determines that the first network device is a network device supporting providing RRC inactive multicast before sending the first information. One possible implementation manner is that the second network device knows, through an interface (for example, an Xn interface) between network devices, that the first network device supports providing a multicast service for the terminal device in the RRC inactive state.

According to the embodiment of the application, under the condition that the first network device performs SDT with the terminal device in RRC inactive state and the first network device provides the first multicast session for the terminal device in RRC inactive state, the first network device can know that the terminal device also joins the first multicast session in the SDT process by sending the second request message to the second network device and receiving the tenth information in part of the context information of the terminal device provided by the second network device, so that the first network device can perform proper scheduling on the SDT and the data of the first multicast session, for example, send the SDT data and the data of the first multicast session in a time slot time division multiplexing mode, or send the SDT data and the data of the first multicast session in a time slot frequency division multiplexing mode, and the like, so that the terminal device can also receive the SDT and the data of the first multicast session in a small data transmission scene without the UE context relocation, and error and/or packet loss caused by scheduling exceeding the receiving capability of the terminal device are avoided. The first network device is a network device corresponding to a serving cell where the terminal device resides in an RRC inactive state, and may also be a receiving gNB that performs SDT with the terminal device.

In this application, the multicast service may refer to an MBS multicast service (multicast service), and the SDT includes data and/or signaling of a downlink/uplink SDT.

S604: the second network device sends eleventh information and/or twelfth information to the first network device, and the first network device receives the eleventh information and/or twelfth information sent by the second network device correspondingly.

The eleventh information is used for indicating that the terminal equipment supports or does not support Frequency Division Multiplexing (FDM) reception of one or more unicast data and one or more multicast data in the same time slot, in other words, the eleventh information is used for indicating that the terminal equipment supports or does not support Frequency Division Multiplexing (FDM) reception of M unicast data and N multicast data in the same time slot, where M and N are integers greater than or equal to 1.

The twelfth information is used to indicate that the terminal device supports or does not support time division multiplexing TDM reception of one or more unicast data and one or more multicast data in the same time slot, in other words, the twelfth information is used to indicate that the terminal device supports or does not support time division multiplexing TDM reception of P unicast data and Q multicast data in the same time slot, where P and Q are integers greater than or equal to 1.

Optionally, the eleventh information is further used to instruct the terminal device to support or not support, on the first frequency band or the carrier of the first frequency band, frequency division multiplexing FDM reception of M unicast data and N multicast data in the same time slot, where M and N are integers greater than or equal to 1; the eleventh information includes an identification of the first frequency band;

optionally, the twelfth information is further used to instruct the terminal device to support or not support time division multiplexing TDM reception of P unicast data and Q multicast data in the same time slot on the second frequency band or a carrier of the second frequency band, where P and Q are integers greater than or equal to 1; the twelfth information includes an identification of the second frequency band; the first frequency band and the second frequency band may be the same frequency band or different frequency bands.

The second network device sends eleventh information and/or twelfth information to the first network device, so that the first network device can learn the capability of the terminal device to receive the SDT data and the multicast data in parallel, and therefore schedule the data in a more flexible manner. For example, when the terminal device supports reception of 1 unicast PDSCH and 1 multicast GC-PDSCH in a frequency division multiplexing manner in the same slot, the first network device may transmit 1 unicast PDSCH and 1 multicast GC-PDSCH in a frequency division multiplexing manner in the same slot. For another example, when the terminal device supports reception of 1 unicast PDSCH and 1 multicast GC-PDSCH in a time division multiplexed manner within the same slot, the first network device may transmit 1 unicast PDSCH and 1 multicast GC-PDSCH in a time division multiplexed manner within the same slot.

In the present embodiment, unicast data may be understood/replaced by PDSCH for transmitting unicast (unicasting) data, or PDSCH scrambled by radio network temporary identity (Cell Radio Network Temporary Identifier, cell RNTI) of a cell; the multicast data may be understood/replaced by PDSCH/GC-PDSCH used for transmitting MBS multicast data or PDSCH scrambled by group radio network temporary identifier (Group Radio Network Temporary Identifier, G-RNTI). The time division multiplexing/frequency division multiplexing of unicast data and multicast data in the same time slot (intra-slot) can be understood as the time division multiplexing/frequency division multiplexing of unicast PDSCH and GC-PDSCH of MBS multicast in the same time slot (intra-slot).

According to the embodiment of the application, the first network device performs SDT with the terminal device in RRC inactive state, and under the scene that the first network device provides multicast session for the terminal device in RRC inactive state, the first network device can know that the terminal device supports or does not support frequency division multiplexing TDM (time division multiplexing) reception or time division multiplexing TDM reception of one or more unicast data and one or more multicast data in the same time slot according to eleventh information and/or twelfth information, so that the first network device can properly schedule the SDT and the multicast session data, and the terminal device can also receive the SDT and the multicast session data under the small data transmission scene without UE context relocation, thereby avoiding error code and/or packet loss caused by exceeding the receiving capability of the terminal device.

It should be understood that the execution sequence of the step S604, the steps S602 and S603 is not specifically limited, and the execution sequence thereof is based on the actual implementation sequence of the scheme.

S605: the first network device provides data and/or signaling of the SDT and the first multicast session to the terminal device, and correspondingly, the terminal device receives the SDT and the first multicast session from the first network device.

One possible implementation is that the first network device schedules the SDT and the data and/or signaling of the first multicast session by inter-slot time division multiplexing (inter-slot TDM), e.g. sends the data of the SDT to the terminal device on slot 1 and sends the data and/or signaling of the first multicast session to the terminal device on slot 2, so that the terminal device may receive the data and/or signaling of the SDT and the first multicast session from the first network device on different slots.

It is to be understood that the terminal device may be receiving the first multicast session from the first network device before step S605, or has not yet started to receive the first multicast session from the first network device, which is not limited in the embodiment of the present application.

SDT in the embodiment of the present application may be understood as downstream SDT data (DL SDT data). Transmitting data of the SDT and the first multicast session on different time slots may be understood/replaced by transmitting PDSCH of the SDT and PDSCH/GC-PDSCH of the first multicast session on different time slots or by transmitting PDSCH of the SDT and PDSCH/GC-PDSCH of the first multicast session in an inter-slot time division multiplexing (inter-slot TDM) manner.

According to the embodiment of the application, in a SDT (SDT without UE context relocation) scenario without UE context relocation, if the terminal device joins the first multicast session from the first network device, the first network device (i.e. the network device corresponding to the serving cell, also referred to as a receiving gNB of the SDT) may learn information of the first multicast session received by the terminal device, so that by scheduling data and/or signaling of the SDT and the first multicast session on different timeslots, the terminal device may receive data and/or signaling from the SDT and the first multicast session sent by the first network device on different timeslots even if the terminal device does not have the capability of receiving unicast data and multicast data on the same timeslot, thereby avoiding error codes and/or packet loss caused by scheduling exceeding the receiving capability of the terminal device.

Referring to fig. 7, fig. 7 is a flow chart of another communication method according to an embodiment of the present application. It will be appreciated that embodiments of the present application may be regarded as reasonable variations or additions to the embodiments of figures 4, 5, 6 described above; alternatively, it is understood that the communication method in the embodiment of the present application may also be regarded as an embodiment that can be executed separately, which is not limited in this application. The communication method provided by the embodiment of the application is applied to the technical field of communication, and comprises the following steps:

S701: the terminal device performs a small data transfer SDT with the first network device and the terminal device joins a second multicast session from the first network device.

The terminal equipment is in an RRC inactive state, the terminal equipment in the RRC inactive state performs SDT with the first network equipment, and the terminal equipment joins a second multicast session from the first network equipment.

S702: the terminal device sends thirteenth information to the first network device, and correspondingly, the first network device receives the thirteenth information sent by the terminal device.

Wherein the thirteenth information includes information of the second multicast session, and the thirteenth information may specifically be TMGI information of the second multicast session. The thirteenth information is used for the first network device to provide data and/or signaling of the second multicast session to the terminal device while performing SDT with the terminal device.

According to the embodiment of the application, under the condition that the terminal equipment is in an RRC inactive state and performs SDT with the first network equipment, and the terminal equipment receives the second multicast session from the first network equipment, the first network equipment can know that the terminal equipment is still receiving the data and/or signaling of the second multicast session in the SDT process by reporting thirteenth information to the first network equipment, so that the first network equipment can properly schedule the SDT and the second multicast session, for example, the SDT data and the data of the second multicast session are sent in a time slot time division multiplexing mode, or the SDT data and the data of the second multicast session are sent in a time slot frequency division multiplexing mode, and the like, so that the terminal equipment can also receive the data and/or signaling of the SDT and the second multicast session in a small data transmission scene without UE context relocation, and error codes and/or packet loss caused by the scheduling exceeding the receiving capability of the terminal equipment are avoided. The first network device is a network device corresponding to a serving cell where the terminal device resides in an RRC inactive state, and may also be a receiving gNB that performs SDT with the terminal device. The first network device is a network device corresponding to a serving cell where the terminal device resides in an RRC inactive state, and may also be a receiving gNB that performs SDT with the terminal device.

In one possible embodiment, the thirteenth information may be carried in a media access control element (MAC CE), or a radio resource control RRC message.

Alternatively, when the thirteenth information is carried in the MAC CE, the first network device may interpret the thirteenth information to obtain information of the multicast session (TMGI of the multicast session) that the terminal device joins.

Optionally, when the thirteenth information is carried in the RRC message, the first network device further needs to forward the thirteenth information to the second network device, and the second network device interprets the thirteenth information to obtain information of the multicast session (TMGI of the multicast session) that the terminal device joins, and then sends the interpreted information of the multicast session (TMGI of the multicast session) that the terminal device joins to the first network device. It will be appreciated that the procedure is similar to the broadcast communication method shown in fig. 5, and specific reference may be made to steps S505 and S506, which are not repeated here.

According to the embodiment of the application, under the condition that the terminal equipment is in an RRC inactive state and performs SDT with the first network equipment, and the terminal equipment receives data of a second multicast session from the first network equipment, the terminal equipment sends a MAC CE or RRC message to the first network equipment, wherein the MAC CE or RRC message comprises thirteenth information for indicating the second multicast session, so that the first network equipment knows that the terminal equipment also joins the second multicast session in the SDT process, and therefore the first network equipment can properly schedule the data of the SDT and the second multicast session, and can also receive the data of the SDT and the second multicast session in a small data transmission scene without UE context relocation, so that data errors and/or packet loss caused by exceeding the receiving capability of the terminal equipment in scheduling are avoided.

S703: the first network device provides data and/or signaling of the SDT and the second multicast session to the terminal device, and correspondingly, the terminal device receives the SDT and the second multicast session sent by the first network device.

After receiving the thirteenth information, the first network device knows that the terminal device also joins the second multicast session in the process of performing SDT with the first network device, and the first network device schedules the SDT and the data and/or signaling of the second multicast session through inter-slot time division multiplexing (inter-slot TDM), for example, sends the data of the SDT to the terminal device in slot 1, and sends the data and/or signaling of the second multicast session to the terminal device in slot 2, so that the terminal device can receive the data and/or signaling of the SDT and the second multicast session from the first network device in different slots.

SDT in the embodiment of the present application may be understood as downstream SDT data (DL SDT data). Transmitting data of the SDT and the second multicast session on different time slots may be understood/replaced by transmitting PDSCH of the SDT and PDSCH/GC-PDSCH of the second multicast session on different time slots or by transmitting PDSCH of the SDT and PDSCH/GC-PDSCH of the second multicast session in an inter-slot time division multiplexing (inter-slot TDM) manner.

According to the embodiment of the application, in a SDT (SDT without UE context relocation) scenario without UE context relocation, if the terminal device receives data and/or signaling of the second multicast session from the first network device, the first network device (i.e. the network device corresponding to the serving cell, which may also be referred to as a receiving gNB of the SDT) may learn information of the second multicast session received by the terminal device, so that the SDT and the data of the second multicast session are scheduled on different timeslots, and even if the terminal device does not have the capability of receiving unicast data and multicast data and/or signaling on the same timeslot, the terminal device may also receive the data and/or signaling of the SDT and the second multicast session from the first network device on different timeslots, so as to avoid data error codes and/or packet loss caused by scheduling exceeding the receiving capability of the terminal device.

The terminal device sends thirteenth information to the first network device, which may indicate that the terminal device supports receiving the MBS multicast service, and the terminal device must choose to support time division multiplexing (inter-slot TDM) reception between PDSCH for transmitting unicast data and PDSCH/GC-PDSCH for transmitting MBS multicast data, so that the first network device sends SDT and data of the second multicast session according to time division multiplexing between timeslots, which may ensure that the terminal device can receive data of the second multicast session during SDT, and avoid error codes and/or packet loss, thereby ensuring service quality of SDT and MBS multicast service. When the terminal device does not support to receive the unicast data and the MBS multicast data in the same time slot, in the SDT scenario without context relocation, the first network device does not have UE capability information, if the first network device does not know that the terminal device is receiving the second multicast session, when the first network device schedules/sends the SDT data (SDT may be understood as a unicast transmission mode) and the data of the second multicast session in the same time slot, the terminal device may not receive the SDT and the multicast data, or the terminal device may only receive one of the SDT and the multicast data, which causes data error code and/or packet loss, and affects service receiving quality. Therefore, by the scheme, the problem that the data transmission of the SDT and the broadcast multicast service scheduled by the network equipment corresponding to the service cell possibly exceeds the receiving capability of the terminal equipment, so that packet loss or error code is caused can be avoided.

Having set forth in detail the methods of embodiments of the present application above, an apparatus for implementing any of the methods of embodiments of the present application is provided below, e.g., an apparatus comprising means to implement the steps performed by the device in any of the methods above.

Referring to fig. 8, fig. 8 is a schematic structural diagram of a communication device according to an embodiment of the present application.

As shown in fig. 8, the communication device 80 may include a transceiver unit 801 and a processing unit 802. The transceiver unit 801 and the processing unit 802 may be software, hardware, or a combination of software and hardware.

The transceiver unit 801 may implement a transmitting function and/or a receiving function, and the transceiver unit 801 may also be described as a communication unit. The transceiver unit 801 may also be a unit integrating an acquisition unit for implementing a receiving function and a transmission unit for implementing a transmitting function. Alternatively, the transceiver unit 801 may be configured to receive information sent by other devices, and may also be configured to send information to other devices.

In one possible design, the communication device 80 may correspond to the terminal device in the method embodiments shown in fig. 4, fig. 5, fig. 6, and fig. 7, where the communication device 80 may be a terminal device or a chip in the terminal device. The communication device 80 may include means for performing the operations performed by the terminal device in the method embodiments shown in the above-mentioned fig. 4, 5, 6 and 7, and each means in the communication device 80 is for implementing the operations performed by the terminal device in the method embodiments shown in the above-mentioned fig. 4, 5, 6 and 7, respectively. Wherein, each unit is described as follows:

A transceiver unit 801, configured to perform small data transmission SDT with a first network device, and interested in receiving or receiving a first broadcast service from the first network device, where the SDT is a transmission of data and/or signaling in radio resource control RRC inactivity, and the first network device is a network device corresponding to a cell where the communication apparatus resides;

the transceiver unit 801 is further configured to send first information to the first network device, where the first information includes information of the first broadcast service, and the first information is used for the first network device to provide the first broadcast service to the communication apparatus.

In a possible implementation manner, the transceiver unit 801 is further configured to receive the SDT and the first broadcast service from the first network device on different timeslots.

In a possible implementation manner, the transceiver unit 801 is further configured to receive second information sent by the first network device and/or third information sent by a second network device, where the second network device is a network device that sends an RRC release message to the communication apparatus;

a processing unit 802, configured to send the first information to the first network device through the transceiver unit 801 according to the second information and/or the third information.

In a possible implementation manner, the transceiver unit 801 is further configured to receive fourth information sent by the first network device and/or fifth information sent by the second network device;

the processing unit 802 is further configured to send, according to the fourth information and/or the fifth information, the first information to the first network device through the transceiver unit 801, where the first information includes TMGI information of the first broadcast service.

the processing unit 802 is further configured to enter an RRC inactive state according to the RRC release message.

In another possible design, the communication apparatus 80 may correspond to the first network device in the method embodiments shown in fig. 4, fig. 5, fig. 6, and fig. 7, where the communication apparatus 80 may be the first network device or a chip in the first network device. The communication apparatus 80 may include means for performing the operations performed by the first network device in the method embodiments shown in fig. 4, 5, 6, and 7 and each means in the communication apparatus 80 is configured to implement the operations performed by the first network device in the method embodiments shown in fig. 4, 5, 6, and 7. Wherein, each unit is described as follows:

a transceiver 801, configured to receive first information sent by a terminal device, where the first information includes information of a first broadcast service that the terminal device is interested in receiving or is receiving, and the communication apparatus is a network device corresponding to a cell where the terminal device resides;

the transceiver unit 801 is further configured to perform small data transmission SDT with the terminal device, and provide the first broadcast service to the terminal device, where the SDT is transmission of data and/or signaling in a radio resource control RRC inactive state.

In a possible implementation manner, the transceiver unit 801 is further configured to send the SDT and the first broadcast service to the terminal device on different timeslots.

In a possible implementation manner, the transceiver unit 801 is further configured to send the first information to a second network device, where the second network device is a network device that connects the terminal device and a core network device;

the transceiver unit 801 is further configured to receive sixth information from the second network device, where the sixth information is used to indicate the first broadcast service, and the sixth information is determined by the first information.

In a possible implementation manner, the transceiver unit 801 is further configured to send a first request message to the second network device, where the first request message is used to request to acquire context information of the terminal device for SDT;

the transceiver 801 is further configured to receive partial context information of the terminal device sent by the second network device, where the partial context information includes seventh information, and the seventh information is used to indicate a second broadcast service received by the terminal device.

In a possible implementation manner, the processing unit 802 is configured to ignore the seventh information if the sixth information is received.

In a possible implementation manner, the transceiver unit 801 is further configured to receive eighth information from the second network device, where the eighth information is used to instruct the terminal device to support or not support reception of M unicast data and N broadcast data in a frequency division multiplexing FDM in the same timeslot, where M and N are integers greater than or equal to 1; and/or the number of the groups of groups,

the transceiver 801 is further configured to receive ninth information from the second network device, where the ninth information is used to indicate that the terminal device supports or does not support time division multiplexing TDM reception of P unicast data and Q broadcast data in the same timeslot, and P and Q are integers greater than or equal to 1.

In another possible design, the communication apparatus 80 may correspond to the second network device in the method embodiments shown in fig. 4, fig. 5, fig. 6, and fig. 7, where the communication apparatus 80 may be the second network device, or may be a chip in the second network device. The communication apparatus 80 may include means for performing the operations performed by the second network device in the method embodiments shown in fig. 4, 5, 6, and 7 and each means in the communication apparatus 80 is configured to implement the operations performed by the second network device in the method embodiments shown in fig. 4, 5, 6, and 7. Wherein, each unit is described as follows:

A transceiver 801, configured to send a small data transmission SDT and sixth information to a first network device, where the sixth information is used to indicate a first broadcast service, where the first broadcast service is a broadcast service that is interested in being received or is being received by a terminal device, the communication device is a network device that connects the terminal device with a core network device, the first network device is a network device corresponding to a cell where the terminal device resides, and the SDT is a transmission of data and/or signaling that is inactive and dynamic in radio resource control RRC by the terminal device, and the SDT is sent to the terminal device through the first network device.

In a possible implementation manner, the transceiver unit 801 is further configured to receive first information sent by the first network device, where the first information includes information of the first broadcast service;

a processing unit 802, configured to determine the sixth information according to the first information.

In a possible implementation manner, the transceiver unit 801 is further configured to receive a first request message sent by the first network device, where the first request message is used to request to acquire context information of the terminal device for SDT;

The transceiver unit 801 is further configured to send, in response to the first request message, partial context information of the terminal device to the first network device, where the partial context information includes seventh information, and the seventh information is used to indicate a second broadcast service received by the terminal device.

In a possible implementation manner, the processing unit 802 is further configured to determine, according to the capability information of the terminal device, that the terminal device does not support receiving unicast data and broadcast data in the same timeslot.

In another possible design, the communication device 80 may correspond to the terminal device in the method embodiments shown in fig. 4, fig. 5, fig. 6, and fig. 7, where the communication device 80 may be a terminal device or a chip in the terminal device. The communication device 80 may include means for performing the operations performed by the terminal device in the method embodiments shown in the above-mentioned fig. 4, 5, 6 and 7, and each means in the communication device 80 is for implementing the operations performed by the terminal device in the method embodiments shown in the above-mentioned fig. 4, 5, 6 and 7, respectively. Wherein, each unit is described as follows:

A transceiver 801, configured to receive a small data transmission SDT sent by a first network device and data of a first multicast session, where the SDT is transmission of data and/or signaling in a radio resource control RRC inactive state, the first network device is a network device corresponding to a cell where the communication apparatus resides, the first multicast session is a multicast session added by the communication apparatus, and tenth information for indicating the first multicast session is sent by a second network device to the first network device, where the second network device is a network device connected to the communication apparatus and a core network device.

A transceiver unit 801, configured to receive tenth information from a second network device, where the tenth information is used to indicate a first multicast session to which a terminal device joins, the communication device is a network device corresponding to a cell in which the terminal resides, and the second network device is a network device that connects the terminal device and a core network device;

the transceiver unit 801 is further configured to send, to the terminal device, a small data transmission SDT and data of the first multicast session, where the SDT is transmission of data and/or signaling in a radio resource control RRC inactive state.

In a possible implementation manner, the transceiver unit 801 is further configured to send a second request message to the second network device, where the second request message is used to request to acquire context information of the terminal device for SDT;

the transceiver 801 is further configured to receive partial context information of the terminal device sent by the second network device, where the partial context information includes the tenth information.

In a possible implementation manner, the transceiving unit 801 is further configured to send the SDT and the data of the first multicast session to the terminal device on different timeslots.

In a possible implementation manner, the transceiver unit 801 is further configured to receive eleventh information from the second network device, where the eleventh information is used to instruct the terminal device to support or not support frequency division multiplexing FDM reception of M unicast data and N multicast data in a time slot, where M and N are integers greater than or equal to 1; and/or the number of the groups of groups,

the transceiver 801 is further configured to receive twelfth information from the second network device, where the twelfth information is used to indicate that the terminal device supports or does not support time division multiplexing TDM reception of P unicast data and Q multicast data in a time slot, and P and Q are integers greater than or equal to 1.

A transceiver unit 801, configured to send a small data transfer SDT and tenth information to a first network device, where the tenth information is used to indicate a first multicast session to which a terminal device joins, the first network device is a network device corresponding to a cell where the terminal resides, and the communication device is a network device that connects the terminal device and a core network device;

In a possible implementation manner, the transceiver unit 801 is further configured to receive a second request message sent by the first network device, where the second request message is used to request to acquire context information of the terminal device for SDT;

the transceiver 801 is further configured to send, to the first network device, partial context information of the terminal device, where the partial context information includes the tenth information.

In a possible implementation manner, the processing unit 802 is configured to determine, according to the capability information of the terminal device, that the terminal device does not support receiving unicast data and multicast data in the same timeslot.

a transceiver 801, configured to perform small data transmission SDT with a first network device, and join a second multicast session from the first network device, where the SDT is a transmission of data and/or signaling in radio resource control RRC inactivity, and the first network device is a network device corresponding to a cell where the communication apparatus resides;

The transceiver unit 801 is further configured to send thirteenth information to the first network device, where the thirteenth information is used to indicate the second multicast session, and the thirteenth information is used to send the second multicast session to the communication device by the first network device.

In a possible implementation, the transceiver unit 801 is further configured to receive data of the SDT and the second multicast session from the first network device on different timeslots.

A transceiver unit 801, configured to receive thirteenth information sent by a terminal device, where the thirteenth information is used to indicate a second multicast session, where the second multicast session is a multicast session added by the terminal device, and the communication device is a network device corresponding to a cell where the terminal device resides;

the transceiver 801 is further configured to perform small data transmission SDT with the terminal device, and send data of the second multicast session to the terminal device, where the SDT is transmission of data and/or signaling in a radio resource control RRC inactive state.

In a possible implementation manner, the transceiving unit 801 is further configured to send the SDT and the data of the second multicast session to the terminal device on different timeslots.

A transceiver unit 801, configured to send a small data transmission SDT to a first network device; the data of the SDT and the second multicast session are sent to the terminal device by the first network device, the SDT is transmission of data and/or signaling of radio resource control RRC inactivity of the terminal device, the first network device is a network device corresponding to a cell where the terminal resides, the communication device is a network device that connects the terminal device and the core network device, the second multicast session is a multicast session that indicates that the terminal device joins by using thirteenth information, and the thirteenth information is from the terminal device.

According to the embodiment of the application, each unit in the apparatus shown in fig. 8 may be separately or all combined into one or several additional units, or some (some) units may be further split into multiple units with smaller functions to form the unit, which may achieve the same operation without affecting the implementation of the technical effects of the embodiment of the application. The above units are divided based on logic functions, and in practical applications, the functions of one unit may be implemented by a plurality of units, or the functions of a plurality of units may be implemented by one unit. In other embodiments of the present application, the electronic device may also include other units, and in practical applications, these functions may also be implemented with assistance from other units, and may be implemented by cooperation of multiple units.

It should be noted that the implementation of each unit may also correspond to the corresponding description of the method embodiments shown in fig. 4, fig. 5, fig. 6, and fig. 7.

In the communication apparatus 80 depicted in fig. 8, it may be realized that, in a small data transmission scenario where the terminal device does not have UE context relocation, the network device corresponding to the serving cell may learn multicast broadcast service information that the terminal device is interested in receiving or is receiving, so as to perform reasonable scheduling and data transmission, so that the terminal device may receive SDT and data of the multicast broadcast service.

Referring to fig. 9, fig. 9 is a schematic structural diagram of a communication device according to an embodiment of the present application.

It should be understood that the communication device 90 shown in fig. 9 is only an example, and the communication device of the embodiment of the present application may further include other components, or include components similar in function to the respective components in fig. 9, or not necessarily include all the components in fig. 9.

The communication device 90 comprises a communication interface 901 and at least one processor 902.

The communication apparatus 90 may correspond to any network element or device of the terminal device, the first network device, and the second network device. The communication interface 901 is configured to receive and transmit signals, and the at least one processor 902 executes program instructions to cause the communication apparatus 90 to implement the respective flow of the method performed by the corresponding device in the above-described method embodiment.

In one possible design, the communication device 90 may correspond to the terminal device in the method embodiments shown in fig. 4, fig. 5, fig. 6, and fig. 7, where, for example, the communication device 90 may be a terminal device or may be a chip in the terminal device. The communication device 90 may include means for performing the operations performed by the terminal apparatus in the above-described method embodiments, and each means in the communication device 90 is respectively for implementing the operations performed by the terminal apparatus in the above-described method embodiments. The method can be specifically as follows:

In another possible design, the communication apparatus 90 may correspond to the first network device in the method embodiments shown in fig. 4, fig. 5, fig. 6, and fig. 7, where the communication apparatus 90 may be the first network device or a chip in the first network device. The communication apparatus 90 may include means for performing the operations performed by the first network device in the above-described method embodiments, and each of the means in the communication apparatus 90 is configured to perform the operations performed by the first network device in the above-described method embodiments, respectively. The method can be specifically as follows:

In another possible design, the communication apparatus 90 may correspond to the second network device in the method embodiments shown in fig. 4, fig. 5, fig. 6, and fig. 7, where the communication apparatus 90 may be the second network device, or may be a chip in the second network device. The communication apparatus 90 may include means for performing the operations performed by the second network device in the above-described method embodiments, and the respective means in the communication apparatus 90 are respectively for implementing the operations performed by the second network device in the above-described method embodiments. The method can be specifically as follows:

In another possible design, the communication device 90 may correspond to the terminal device in the method embodiments shown in fig. 4, fig. 5, fig. 6, and fig. 7, where, for example, the communication device 90 may be a terminal device or a chip in the terminal device. The communication device 90 may include means for performing the operations performed by the terminal apparatus in the above-described method embodiments, and each means in the communication device 90 is respectively for implementing the operations performed by the terminal apparatus in the above-described method embodiments. The method can be specifically as follows:

The method comprises the steps that first network equipment receives tenth information from second network equipment, wherein the tenth information is used for indicating a first multicast session added by terminal equipment, the first network equipment is network equipment corresponding to a cell where a terminal resides, and the second network equipment is network equipment for connecting the terminal equipment and core network equipment;

the second network device sends a small data transmission SDT to the first network device; the data of the SDT and the second multicast session are sent to the terminal device by the first network device, the SDT is transmission of data and/or signaling of radio resource control RRC inactivity of the terminal device, the first network device is a network device corresponding to a cell where the terminal resides, the second network device is a network device connected to the terminal device and the core network device, the second multicast session is a multicast session in which thirteenth information indicates the terminal device to join, and the thirteenth information is from the terminal device.

In the communication apparatus 90 described in fig. 9, it may be realized that in a small data transmission scenario where the terminal device does not have UE context relocation, the network device corresponding to the serving cell may learn multicast broadcast service information that the terminal device is interested in receiving or is receiving, so as to perform reasonable scheduling and data transmission, so that the terminal device may receive SDT and data of the multicast broadcast service.

For the case where the communication device may be a chip or a chip system, reference may be made to the schematic structure of the chip shown in fig. 10.

As shown in fig. 10, the chip 100 includes a processor 1001 and an interface 1002. Wherein the number of processors 1001 may be one or more, and the number of interfaces 1002 may be a plurality. The functions corresponding to the processor 1001 and the interface 1002 may be implemented by a hardware design, a software design, or a combination of hardware and software, which is not limited herein.

Optionally, the chip 100 may further comprise a memory 1003, the memory 1003 being adapted to store necessary program instructions and data.

In this application, the processor 1001 may be configured to invoke, from the memory 1003, a program for implementing a communication method provided in one or more of a terminal device, a first network device, and a second network device, or a network element, and execute instructions included in the program. Interface 1002 may be used to output results of execution by processor 1001. In this application, interface 1002 may be used specifically to output various messages or information from processor 1001.

The communication method provided in one or more embodiments of the present application may refer to the foregoing embodiments shown in fig. 4, fig. 5, fig. 6, and fig. 7, and will not be described herein.

The processor in embodiments of the present application may be a central processing unit (Central Processing Unit, CPU), but may also be other general purpose processors, digital signal processors (digital signal processor, DSP), application specific integrated circuits (application specific integrated circuit, ASIC), off-the-shelf programmable gate arrays (field programmable gate array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The memory in the embodiments of the present application is configured to provide a storage space, where data such as an operating system and a computer program may be stored. The memory includes, but is not limited to, random access memory (random access memory, RAM), read-only memory (ROM), erasable programmable read-only memory (erasable programmable read only memory, EPROM), or portable read-only memory (compact disc read-only memory, CD-ROM).

According to the method provided by the embodiment of the application, the embodiment of the application further provides a computer readable storage medium, where a computer program is stored, and when the computer program runs on one or more processors, the method shown in fig. 4, fig. 5, fig. 6 and fig. 7 can be implemented.

According to the method provided by the embodiment of the application, the embodiment of the application further provides a computer program product, and the computer program product comprises a computer program, and when the computer program runs on a processor, the method shown in fig. 4, fig. 5, fig. 6 and fig. 7 can be implemented.

The present embodiment also provides a system, which includes at least one communication device 80 or 90 or chip 100 as described above, for performing the steps performed by the corresponding apparatus in any of the embodiments of fig. 4, 5, 6, and 7 as described above.

The embodiment of the application further provides a system, which includes a terminal device, a first network device, and a second network device, where the terminal device is configured to execute the steps executed by the terminal device in any embodiment of fig. 4, fig. 5, fig. 6, and fig. 7, and the first network device is configured to execute the steps executed by the first network device in any embodiment of fig. 4, fig. 5, fig. 6, and fig. 7, and the second network device is configured to execute the steps executed by the second network device in any embodiment of fig. 4, fig. 5, fig. 6, and fig. 7.

The embodiment of the application also provides a processing device, which comprises a processor and an interface; the processor is configured to perform the method of any of the method embodiments described above.

It should be understood that the processing means may be a chip. For example, the processing means may be a field programmable gate array (field programmable gate array, FPGA), a general purpose processor, a digital signal processor (digital signal processor, DSP), an application specific integrated circuit (application specific integrated circuit, ASIC), an off-the-shelf programmable gate array (field programmable gate array, FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware components, a system on chip (SoC), a central processor (central processor unit, CPU), a network processor (network processor, NP), a digital signal processing circuit (digital signal processor, DSP), a microcontroller (micro controller unit, MCU), a programmable controller (programmable logic device, PLD) or other integrated chip. The disclosed methods, steps, and logic blocks in the embodiments of the present application may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present application may be embodied directly in hardware, in a decoded processor, or in a combination of hardware and software modules in a decoded processor. The software modules may be located in a random access memory, flash memory, read only memory, programmable read only memory, or electrically erasable programmable memory, registers, etc. as well known in the art. The storage medium is located in a memory, and the processor reads the information in the memory and, in combination with its hardware, performs the steps of the above method.

It will be appreciated that the memory in embodiments of the present application may be either volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. The nonvolatile memory may be a read-only memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an electrically Erasable EPROM (EEPROM), or a flash memory. The volatile memory may be random access memory (random access memory, RAM) which acts as an external cache. By way of example, and not limitation, many forms of RAM are available, such as Static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous DRAM (SLDRAM), and direct memory bus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, the processes or functions described in accordance with embodiments of the present application are produced in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by a wired (e.g., coaxial cable, fiber optic, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. that contains an integration of one or more available media. The usable medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a high-density digital video disc (digital video disc, DVD)), or a semiconductor medium (e.g., a Solid State Disk (SSD)), or the like.

The units in the above-mentioned respective apparatus embodiments and the electronic devices in the method embodiments correspond exactly, and the respective steps are performed by respective modules or units, for example, the communication unit (transceiver) performs the steps of receiving or transmitting in the method embodiments, and other steps than transmitting and receiving may be performed by the processing unit (processor). Reference may be made to corresponding method embodiments for the function of a specific unit. Wherein the processor may be one or more.

It will be appreciated that in the embodiments of the present application, the electronic device may perform some or all of the steps in the embodiments of the present application, these steps or operations are merely examples, and other operations or variations of the various operations may also be performed by the embodiments of the present application. Furthermore, the various steps may be performed in a different order presented in accordance with embodiments of the present application, and it is possible that not all of the operations in the embodiments of the present application may be performed.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It will be clear to those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, and are not repeated herein.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer-readable storage medium. Based on such understanding, the technical solution of the present application may be embodied in essence or contributing part or part of the technical solution in the form of a software product stored in a storage medium, including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in the embodiments of the present application. And the aforementioned storage medium includes: a usb disk, a removable hard disk, a ROM, a RAM, a magnetic disk, or an optical disk, or other various media capable of storing program codes.

The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes and substitutions are intended to be covered by the scope of the present application.

Claims

1. A method of communication, comprising:

2. The method of claim 1, wherein before the terminal device sends the first information to the first network device, the method further comprises:

3. The method according to claim 1 or 2, wherein the information of the first broadcast service comprises temporary mobile group identity, TMGI, information; before the terminal device sends the first information to the first network device, the method further includes:

4. A method according to claim 2 or 3, characterized in that the third information and/or the fifth information is carried in an RRC release message; the method further comprises the steps of:

5. A method according to claim 2 or 3, characterized in that the second information, and/or the third information, and/or the fourth information, and/or the fifth information comprises system information.

6. The method according to claim 5, wherein the second information and/or the third information comprises first system information indicating a mapping relationship between multicast broadcast services and frequencies or indicating configuration parameters of a multicast broadcast service control channel MCCH.

7. The method according to claim 5, wherein the fourth information and/or the fifth information comprises second system information indicating a mapping relationship between multicast broadcast services and frequencies or indicating configuration parameters of a multicast broadcast service control channel MCCH.

8. A method of communication, comprising:

9. The method of claim 8, wherein the method further comprises:

10. The method according to claim 8 or 9, characterized in that the method further comprises:

11. The method according to claim 10, wherein the method further comprises:

12. The method according to any one of claims 8 to 11, further comprising:

13. A method of communication, comprising:

14. The method of claim 13, wherein the method further comprises:

15. The method according to claim 13 or 14, characterized in that the method further comprises:

16. The method according to any of claims 13 to 15, wherein before the second network device sends the sixth information to the first network device, the method further comprises:

17. A method of communication, comprising:

18. The method of claim 17, wherein the tenth information is carried in part of the context information of the terminal device that the second network device sends to the first network device.

19. A method of communication, comprising:

20. The method of claim 19, wherein the first network device receiving tenth information from the second network device comprises:

21. The method according to claim 19 or 20, characterized in that the method further comprises:

the first network device receives eleventh information from the second network device, where the eleventh information is used to instruct the terminal device to support or not support reception of M unicast data and N multicast data in a frequency division multiplexing FDM in a time slot, and M and N are integers greater than or equal to 1; and/or the number of the groups of groups,

The first network device receives twelfth information from the second network device, where the twelfth information is used to indicate that the terminal device supports or does not support time division multiplexing TDM reception of P unicast data and Q multicast data in a time slot, and P and Q are integers greater than or equal to 1.

22. A method of communication, comprising:

23. The method of claim 22, wherein the second network device transmitting tenth information to the first network device comprises:

24. The method according to claim 22 or 23, wherein before the second network device sends tenth information to the first network device, the method further comprises:

25. A communication device comprising means or units for performing the method of any of claims 1 to 7 or claims 8 to 12 or claims 13 to 16 or claims 17 to 18 or claims 19 to 21 or claims 22 to 24.

26. A communication device, comprising: a processor;

the computer program or instructions, when invoked by the processor in memory, cause the method of any one of claims 1 to 7, or the method of any one of claims 8 to 12, or the method of any one of claims 13 to 16, or the method of any one of claims 17 to 18, or the method of any one of claims 19 to 21, or the method of any one of claims 22 to 24 to be performed.

27. A communication device comprising logic circuitry and an interface, the logic circuitry and the interface coupled;

the interface is used for inputting data to be processed, the logic circuit processes the data to be processed according to the method of any one of claims 1 to 7 or claims 8 to 12 or claims 13 to 16 or claims 17 to 18 or claims 19 to 21 or claims 22 to 24 to obtain processed data, and the interface is used for outputting the processed data.

28. A computer-readable storage medium, comprising:

the computer readable storage medium is used for storing instructions or a computer program; when the instructions or the computer program are executed, cause the method of any one of claims 1 to 7, or the method of any one of claims 8 to 12, or the method of any one of claims 13 to 16, or the method of any one of claims 17 to 18, or the method of any one of claims 19 to 21, or the method of any one of claims 22 to 24 to be implemented.

29. A computer program product, comprising: instructions or computer programs;

The instructions or the computer program, when executed, cause the method of any one of claims 1 to 7, or the method of any one of claims 8 to 12, or the method of any one of claims 13 to 16, or the method of any one of claims 17 to 18, or the method of any one of claims 19 to 21, or the method of any one of claims 22 to 24 to be performed.

30. A communication system comprising a communication device according to claim 25, or a communication device according to claim 26, or a communication device according to claim 27.

31. A communication system, comprising: terminal equipment, first network equipment and second network equipment;

the terminal device being configured to perform the method of any of claims 1 to 7, the first network device being configured to perform the method of any of claims 8 to 12, the second network device being configured to perform the method of any of claims 13 to 16; or,

the terminal device being adapted to perform the method of any of claims 17 to 18, the first network device being adapted to perform the method of any of claims 19 to 21, the second network device being adapted to perform the method of any of claims 22 to 24.