CN117377001A

CN117377001A - Wireless relay communication method and communication device

Info

Publication number: CN117377001A
Application number: CN202210780579.2A
Authority: CN
Inventors: 徐瑞雄; 彭文杰; 李翔宇
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2022-06-30
Filing date: 2022-06-30
Publication date: 2024-01-09
Also published as: WO2024001792A1

Abstract

A wireless relay communication method and a communication device are applied to the field of wireless communication. For a first terminal and a second terminal with an air interface link or a first terminal and a second terminal which communicate through a relay device, when the quality of the air interface link or the relay link between the first terminal and the second terminal is poor, the first terminal can select a new relay device to provide relay connection for the two terminals, and respectively establish unicast connection with the new relay device, and then the two terminals communicate through the new relay device.

Description

Wireless relay communication method and communication device

Technical Field

The embodiment of the application relates to the field of wireless communication, and more particularly relates to a wireless relay communication method and a communication device.

Background

To enhance network coverage, a 5G New Radio (NR) system introduces device-to-device (D2D) communication and relay communication between terminals.

However, whether it is direct communication between terminals or relay communication between terminals, the quality of the link between terminals or the quality of the link between terminals and relays may be deteriorated for some reasons, for example, because of movement of terminals or relays or changes in external environment, in which case the quality of communication between terminals cannot be ensured.

Disclosure of Invention

The application provides a wireless relay communication method in order to ensure the quality of communication between two terminals in a D2D communication scene.

In a first aspect, a method for wireless relay communication is provided, including: a first terminal obtains the quality of a source link, wherein the source link comprises an air interface link between the first terminal and the second terminal, or the source link comprises a first source link and a second source link, the first source link is an air interface link between the first terminal and a second relay, and the second source link is an air interface link between the second relay and the second terminal; then, if the first condition is satisfied, the first terminal establishes a unicast connection with a first relay, the first relay being a terminal capable of providing relay transmission for the first terminal and the second terminal; in addition to establishing unicast connection with a first relay, a first terminal sends first indication information to the second terminal, wherein the first indication information indicates that unicast connection is established between the second terminal and the first relay, or the first terminal sends first indication information to the first relay and indicates that unicast connection is established between the first relay and the second terminal. The first condition is used for determining whether the quality of the air interface direct link is poor or whether the quality of the first source link and/or the quality of the second source link is poor.

Based on the above technical solution, the quality of the air interface link between the first terminal and the second terminal is poor, or in the case that the quality of the first source link and/or the quality of the second source link is poor, the first terminal determines the first relay capable of providing relay transmission for the first terminal and the second terminal as a target relay, in other words, the first terminal selects a new relay to provide relay connection for the first terminal and the second terminal, and the first terminal and the second terminal respectively establish unicast connection with the first relay, and the subsequent first terminal and the second terminal communicate through the first relay, thereby guaranteeing the quality of communication between the first terminal and the second terminal.

As one implementation, the first condition includes at least one of: the quality of the first source link is less than a first threshold and the quality of the second source link is less than the first threshold.

Based on the above technical solution, the first terminal may determine whether the first condition is satisfied according to the quality of the first source link and/or the quality of the second source link, for example, if the quality of the first source link is less than a first threshold, and/or if the quality of the second source link is less than the first threshold, the first terminal may determine that the first condition is satisfied.

As one implementation, the first condition includes: the quality of the air interface link between the first terminal and the second terminal is less than a second threshold.

Based on the above technical solution, the first terminal may determine whether the first condition is satisfied according to the quality of the air interface link between the first terminal and the second terminal, for example, if the quality of the air interface link between the first terminal and the second terminal is less than the second threshold, the first terminal may determine that the first condition is satisfied.

As one implementation, the difference between the quality of the first target link and the quality of the first source link is greater than or equal to a third threshold, and the difference between the quality of the second target link and the quality of the second source link is greater than or equal to the third threshold, where the first target link is an air interface link between the first terminal and the first relay, and the second target link is an air interface link between the first relay and the second terminal.

Based on the above technical solution, the first terminal may determine whether the first condition is satisfied according to the quality of the first target link, the quality of the second target link, the quality of the first source link, and the quality of the second source link, for example, if the difference between the quality of the first target link and the quality of the first source link is greater than or equal to a third threshold, and the difference between the quality of the second target link and the quality of the second source link is greater than or equal to the third threshold, the first terminal may determine that the first condition is satisfied.

As one implementation, the first condition includes: the difference between the quality of a first target link and the quality of an air interface link between a first terminal and a second terminal is greater than or equal to a fourth threshold, and the difference between the quality of a second target link and the quality of the air interface link is greater than or equal to the fourth threshold, the first target link being the air interface link between the first terminal and the first relay, the second target link being the air interface link between the first relay and the second terminal.

Based on the above technical solution, the first terminal may determine whether the first condition is satisfied according to the quality of the air interface link between the first terminal and the second terminal and the quality of the first target link and the quality of the second target link, for example, if the difference between the quality of the first target link and the quality of the air interface link between the first terminal and the second terminal is greater than or equal to a fourth threshold, and the difference between the quality of the second target link and the quality of the air interface link is greater than or equal to a fourth threshold, the first terminal may determine that the first condition is satisfied.

As an implementation manner, the first indication information carries a first identifier allocated by the first terminal and used for identifying the second terminal.

As an implementation manner, if the first terminal sends first indication information to the second terminal, and the first indication information carries the first identifier, the method further includes: and the first terminal sends the first identification to the first relay.

Based on the technical scheme, the first terminal sends the first identifier which is distributed by the first terminal and used for identifying the second terminal to the second terminal, the second terminal sends the first identifier to the first relay, and when the first relay subsequently receives the data from the first terminal, the second terminal can be determined to be the destination terminal of the data according to the first identifier sent together with the data. In other words, the first relay determines that the first target link is associated with the second target link, forwarding data from the first terminal to the second terminal; or when the first relay subsequently receives the data from the second terminal, the first terminal can be determined to be the target terminal according to the first identifier sent together with the data.

As an implementation, the method further includes: the first terminal receives a second identifier from the second terminal, wherein the second identifier is a layer two identifier of the second terminal for establishing unicast connection with the first relay; and sending the second identification to the first relay.

Based on the technical scheme, the second terminal firstly sends the layer two identifier of the second terminal for establishing unicast connection with the first relay to the first terminal, and then the first terminal sends the layer two identifier of the second terminal to the first relay. When the communication connection is established between the two terminals, the communication connection between the two terminals is identified by using the layer two identification of the source terminal and the layer two identification pair of the destination terminal. For example, when a communication connection is established between a first terminal and a second terminal, the communication connection is identified using a layer two identification pair of the first terminal and the second terminal. When the first relay subsequently receives the data from the first terminal, it may determine that the layer two identifier pair of the first terminal and the layer two identifier pair of the second terminal included in the data are used to identify a communication connection between the first terminal and the second terminal according to the source address (i.e., the layer two identifier of the first terminal) sent with the data, thereby determining that the second terminal is a destination terminal. Or when the first relay subsequently receives the data from the second terminal, the layer two identifier pair of the second terminal and the layer two identifier pair of the first terminal included in the data can be determined to be used for identifying the communication connection between the first terminal and the second terminal according to the source address (namely, the layer two identifier of the second terminal) sent along with the data, so that the first terminal is determined to be the destination terminal.

In a second aspect, a method of wireless relay communication is provided, comprising: a second terminal receives first indication information from a first terminal, wherein the first indication information indicates that unicast connection is established between the second terminal and a first relay, and the first relay is a terminal capable of providing relay transmission for the first terminal and the second terminal; and then, the unicast connection is established between the second terminal and the first relay. Regarding the advantages of the second aspect, please refer to the related description of the advantages of the first aspect, and the description thereof is omitted herein for brevity.

As an implementation manner, the first indication information carries an identifier allocated by the first terminal and used for identifying the second terminal.

As an implementation manner, if the first indication information carries a first identifier, the method further includes: and sending the first identification to the first relay.

As an implementation, the method further includes: and the second terminal sends a second identifier of the second terminal to the first terminal, wherein the second identifier is a layer two identifier of the second terminal for establishing unicast connection with the first relay.

In a third aspect, a method of wireless relay communication is provided, comprising: the method comprises the steps that a first relay receives first indication information from a first terminal, wherein the first indication information indicates that unicast connection is established between the first relay and a second terminal; and then, a unicast connection is established between a first relay and the second terminal, wherein the first relay is a terminal capable of providing relay transmission for the first terminal and the second terminal. Regarding the advantages of the third aspect, please refer to the related description of the advantages of the first aspect, and the description is omitted herein for brevity.

As an implementation, the method further includes: the first relay receives a second identifier of the second terminal from the first terminal, wherein the second identifier is a layer two identifier of the second terminal for establishing unicast connection with the first relay.

In a fourth aspect, a method of wireless relay communication is provided, including: the method comprises the steps that a first terminal broadcasts a direct communication request message, the direct communication request message requests a second terminal to reselect a relay, and unicast connection is established between the relay and the first terminal; thereafter, the first terminal receives a direct communication accept message indicating that the second terminal has completed establishment of a unicast connection with the first terminal.

Based on the above technical solution, the first terminal broadcasts a DCR capable of indicating the second terminal to reselect a relay, and the method can enable the second terminal to receive the DCR in the case that RLF occurs in the source link, and reselect a relay capable of providing relay transmission for the first terminal and the second terminal according to the indication of the DCR, so as to ensure normal communication between the first terminal and the second terminal.

In a fifth aspect, a method of wireless relay communication is provided, comprising: the second terminal receives a direct communication request message, and the direct communication request message requests the second terminal to reselect a relay and establishes unicast connection with the first terminal through the relay; and then, the second terminal sends a direct communication acceptance message to the first terminal, wherein the direct communication acceptance message indicates that the second terminal has completed the establishment of the unicast connection with the first terminal. Regarding the advantages of the fifth aspect, please refer to the related description of the advantages of the fourth aspect, which is omitted for brevity.

In a sixth aspect, a method for wireless relay communication is provided, including: a second relay acquires the quality of a source link, wherein the source link comprises an air interface link between the first terminal and the second terminal, or the source link comprises a first source link and a second source link, the first source link is a link between the first terminal and the second relay, and the second source link is a link between the second relay and the second terminal; then, if the first condition is met, a second relay sends second indication information to the first terminal, the second indication information indicates that unicast connection is established between the first terminal and the first relay, and the second relay sends third indication information to the second terminal, the third indication information indicates that unicast connection is established between the second terminal and the first relay, and the first relay is a terminal capable of providing relay transmission for the first terminal and the second terminal.

Based on the above technical solution, the quality of the air interface link between the first terminal and the second terminal is poor, or in the case that the quality of the first source link and/or the quality of the second source link is poor, the second relay determines the first relay capable of providing relay transmission for the first terminal and the second terminal as a target relay, in other words, the second relay selects a new relay to provide relay connection for the first terminal and the second terminal, and the second relay instructs the first terminal and the second terminal to establish unicast connection with the first relay respectively, and then the first terminal and the second terminal communicate through the first relay, thereby guaranteeing the quality of communication between the first terminal and the second terminal.

As one implementation, the first condition includes: the difference between the quality of the first target link and the quality of the first source link is greater than or equal to a third threshold, and the difference between the quality of the second target link and the quality of the second source link is greater than or equal to the third threshold, the first target link being a link between the first terminal and the first relay, the second target link being a link between the first relay and the second terminal.

As one implementation, the first condition includes: the difference between the quality of the first target link and the quality of the air interface link is greater than or equal to a fourth threshold, and the difference between the quality of the second target link and the quality of the air interface link is greater than or equal to the fourth threshold, the first target link being a link between the first terminal and the first relay, the second target link being a link between the first relay and the second terminal.

As an implementation, the method further includes: a second relay receives a second identifier of the first terminal from the first terminal, wherein the second identifier of the first terminal is a layer two identifier of the first terminal for establishing unicast connection with the first relay; and then, the second relay transmits a second identification of the first terminal to the second terminal.

Based on the technical scheme, the first terminal sends the layer two identifier of the first terminal for establishing unicast connection with the first relay to the second relay, the second relay sends the layer two identifier of the first terminal to the second terminal, and the second terminal sends the layer two identifier of the first terminal to the first relay. When a communication connection is established between two terminals, a layer two identifier of a source terminal and a layer two identifier pair of a destination terminal are used for identifying the communication connection between the two terminals, for example, when the communication connection is established between a first terminal and a second terminal, the layer two identifier pair of the first terminal and the layer two identifier pair of the second terminal are used for identifying the communication connection, and when the first relay subsequently receives data from the first terminal, the layer two identifier pair of the first terminal and the layer two identifier pair of the second terminal included in the data can be determined according to a source address (namely the layer two identifier of the first terminal) sent together with the data, so that the communication connection between the first terminal and the second terminal is identified, and the second terminal is determined to be the destination terminal. Or when the first relay subsequently receives the data from the second terminal, the layer two identifier pair of the second terminal and the layer two identifier pair of the first terminal included in the data can be determined to be used for identifying the communication connection between the first terminal and the second terminal according to the source address (namely, the layer two identifier of the second terminal) sent along with the data, so that the first terminal is determined to be the destination terminal.

As an implementation, the method further includes: a second relay receives a second identifier of a second terminal from the second terminal, wherein the second identifier of the second terminal is a layer two identifier of the second terminal for establishing unicast connection with the first relay; and then, the second relay transmits a second identification of the second terminal to the first terminal.

Based on the technical scheme, the second terminal sends the layer two identifier of the second terminal for establishing unicast connection with the first relay to the second relay, the second relay sends the layer two identifier of the second terminal to the first terminal, and the first terminal sends the layer two identifier of the second terminal to the first relay. The layer two identification pair used when establishing a communication connection between two terminals identifies the communication connection between the two terminals. For example, when a communication connection is established between the first terminal and the second terminal, the communication connection is identified by using a layer two identification pair of the first terminal and a layer two identification pair of the second terminal, and when the first relay subsequently receives data from the first terminal, the layer two identification pair of the first terminal and the layer two identification pair of the second terminal included in the data can be determined according to a destination address (i.e., the layer two identification of the second terminal) sent with the data, so that the communication connection between the first terminal and the second terminal is identified, and the second terminal is determined to be the destination terminal. Alternatively, when the first relay subsequently receives the data from the second terminal, it may determine that the layer two identification pair of the second terminal and the layer two identification pair of the first terminal included in the data is used to identify the communication connection between the first terminal and the second terminal according to the source address (i.e., the layer two identification of the second terminal) transmitted with the data, thereby determining that the first terminal is the destination terminal.

In a sixth aspect, a method for wireless relay communication is provided, including: the first terminal receives second indication information from a second relay, wherein the second indication information indicates that unicast connection is established between the first terminal and the first relay; and then, a unicast connection is established between a first terminal and the first relay, wherein the first relay is a terminal capable of providing relay transmission for the first terminal and the second terminal.

As an implementation, the method further includes: the first terminal sends a second identifier of the first terminal to the second relay, wherein the second identifier of the first terminal is a layer two identifier of the first terminal for establishing unicast connection with the first relay.

As an implementation, the method further includes: the first terminal receives a second identifier of a second terminal from the second relay, wherein the second identifier of the second terminal is a layer two identifier of the second terminal for establishing unicast connection with the first relay; and the first terminal sends the second identification of the second terminal to the first relay.

In a seventh aspect, a method for wireless relay communication is provided, including: the second terminal receives third indication information from the second relay, wherein the third indication information indicates that unicast connection is established between the second terminal and the first relay; and then, a unicast connection is established between a second terminal and the first relay, wherein the first relay is a terminal capable of providing relay transmission for the first terminal and the second terminal.

As an implementation, the method further includes: and the second terminal sends a second identifier of the second terminal to the second relay, wherein the second identifier of the second terminal is a layer two identifier of the second terminal for establishing unicast connection with the first relay.

As an implementation, the method further includes: a second terminal receives a second identifier from a first terminal of the second relay, wherein the second identifier is a layer two identifier of the first terminal for establishing unicast connection with the first relay; and then, the second terminal sends the second identification of the first terminal to the first relay.

In an eighth aspect, a communication device is provided, which may be a terminal or a relay in the above method, or a module applied in a terminal or a relay. The communication device includes: a processor, coupled to the memory, operable to execute instructions in the memory to implement a method performed by the terminal or relay in any one of the above aspects and any one of its possible implementations. 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.

When the communication device is a terminal or a relay, the communication interface may be a transceiver, or an input/output interface.

Alternatively, the transceiver may be a transceiver circuit. Alternatively, the input/output interface may be an input/output circuit.

A ninth aspect provides a program for performing any of the methods of any of the aspects and possible implementations thereof, when executed by a communication device.

In a tenth aspect, there is provided a program product comprising: program code which, when run by a communication device, causes the communication device to perform any of the methods of any of the aspects and possible implementations thereof.

In an eleventh aspect, there is provided a computer readable storage medium storing a program which, when executed, causes a communication device to perform any of the methods of any of the above aspects and possible implementations thereof.

In a twelfth aspect, a communication system is provided, the communication system including the first terminal, the second terminal, the first relay, and the second relay.

Drawings

Fig. 1 is a schematic architecture diagram of a communication system applied in an embodiment of the present application;

FIG. 2 is a schematic flow chart of an example method for determining a target relay provided in an embodiment of the present application;

fig. 3 is a schematic diagram of an example application scenario provided in an embodiment of the present application;

FIG. 4 is a schematic flow chart of another example method for determining a target relay provided by embodiments of the present application;

fig. 5 is a schematic diagram of another application scenario provided in an embodiment of the present application;

fig. 6 is a schematic flow chart of an example of a method of wireless relay communication provided in an embodiment of the present application;

fig. 7 is a schematic flow chart of a method for establishing a unicast connection provided by an embodiment of the present application;

FIG. 8 is a schematic flow chart diagram of another example wireless relay communication method provided by embodiments of the present application;

FIG. 9 is a schematic flow chart diagram of another example of a method for determining a target relay provided by an embodiment of the present application;

fig. 10 is a schematic flow chart of another example of a method of wireless relay communication provided in an embodiment of the present application;

fig. 11 is a schematic flowchart of another example of a method of wireless relay communication provided in an embodiment of the present application;

FIG. 12 is a schematic block diagram of an example communication device provided by an embodiment of the present application;

fig. 13 is a schematic block diagram of another example communication apparatus provided by an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings.

Fig. 1 is a schematic architecture diagram of a communication system 100 to which embodiments of the present application apply. As shown in fig. 1, the communication system includes a plurality of terminals (e.g., 101, 102, 103 in fig. 1), and the plurality of terminals can directly communicate with each other.

In the embodiment of the present application, the link between the two terminals may be a Sidelink (SL), and the communication interface between the two terminals may be a PC5 interface.

Optionally, the communication system 100 may further include one or more radio access network devices (e.g., 104 in fig. 1), with which a plurality of terminals may each communicate.

The radio access network device is an access device to which the terminal accesses the communication system by wireless. The radio access network device may be a base station (base station), an evolved NodeB (eNodeB), a transmission and reception point (transmission reception point, TRP), a next generation NodeB (gNB) in a fifth generation (5th generation,5G) mobile communication system, a next generation base station in a sixth generation (6th generation,6G) mobile communication system, a base station in a future mobile communication system, or an access node in a WiFi system, etc.; the present invention may also be a module or unit that performs a function of a base station part, for example, a Central Unit (CU) or a Distributed Unit (DU).

A terminal is a device having a wireless transceiving function, and can transmit a signal to a base station or receive a signal from a base station. A terminal may also be referred to as a terminal device, user Equipment (UE), mobile station, mobile terminal, etc. The terminal may be widely applied to various scenes, for example, device-to-device (D2D), vehicle-to-device (vehicle to everything, V2X) communication, machine-type communication (MTC), internet of things (internet of things, IOT), virtual reality, augmented reality, industrial control, autopilot, telemedicine, smart grid, smart furniture, smart office, smart wear, smart transportation, smart city, and the like. The terminal can be a mobile phone, a tablet personal computer, a computer with a wireless receiving and transmitting function, a wearable device, a vehicle, an airplane, a ship, a robot, a mechanical arm, intelligent household equipment and the like. The embodiment of the application does not limit the specific technology and the specific equipment form adopted by the terminal.

In the embodiments of the present application, the functions of the terminal may be performed by a module (such as a chip or a modem) in the terminal, or may be performed by an apparatus including the functions of the terminal.

In the D2D communication scenario, when the wireless signal quality between two terminals is poor or one terminal is out of coverage of the other terminal, in order to enhance network coverage of SL, one terminal may be found near the two terminals, and the terminal may be used as a relay for the two terminals, that is, the two terminals may perform data and signaling transfer through the relay device.

However, when any one of the two terminals and the relay device moves or the external environment changes, the quality of the link between one terminal and the relay device and/or the link between the relay and the other terminal may be deteriorated or even interrupted, so that the quality of D2D communication cannot be ensured.

In view of this, embodiments of the present application provide a wireless relay communication method, for two terminals that have an air interface link, or two terminals that communicate through a relay device, for example, a first terminal and a second terminal, the first terminal may acquire the quality of the air interface link between the two terminals or the quality of a relay link between the two terminals (for example, a relay link between the first terminal and the second relay, and a relay link between the second terminal and the second relay), and when the quality of the air interface link or the relay link is poor, the first terminal selects a new relay device to provide relay connections for the two terminals and establish unicast connections with the new relay device, respectively, and then the two terminals communicate through the new relay device in order to guarantee the quality of communication between the two terminals. In this application, the air interface link may also be referred to as an air interface direct link, i.e. two terminals communicate directly through an air interface without relaying transmission capability through other devices.

Hereinafter, a communication method provided in an embodiment of the present application will be described in detail with reference to fig. 2 to 11.

In the embodiment of the present application, a communication method provided in the embodiment of the present application will be described by taking a terminal as an execution subject. As an example and not by way of limitation, the execution body that executes the communication method provided by the embodiments of the present application may also be a module applied to a terminal.

Fig. 2 illustrates a schematic flow chart of an example method 200 for determining a target relay according to an embodiment of the present application. Each step of the method 200 is described in detail below.

In step 201, the first terminal obtains the quality of the first source link and the quality of the second source link.

It is assumed that a communication connection exists between the first terminal and the second terminal, for example, communication is currently performed between the first terminal and the second terminal through the second relay in fig. 3, wherein a link between the first terminal and the second relay is referred to as a first source link, and a link between the second relay and the second terminal is referred to as a second source link. In this application, the relay apparatus is simply referred to as a relay, and the relay may be other terminals than the first terminal and the second terminal.

The first terminal may acquire the quality of the link between itself and the second relay, i.e. the quality of the first source link, and acquire the quality of the link between the second relay and the second terminal, i.e. the quality of the second source link.

In this application, the quality of a link may be characterized by any of the following parameters: reference signal received power (reference signal received power, RSRP), signal to interference plus noise ratio (signal to interference plus noise ratio, SINR), reference signal received quality (reference signal received quality, RSRQ), and a strength indication of the received signal (received signal strength indicator, RSSI).

The measurement signals (e.g., the first measurement signal and the second measurement signal herein) may be demodulation signals (demodulation reference signal, DMRS), data, or other signals.

The first terminal sends the first measurement configuration and the first measurement signal to the second relay, and sends measurement indication information to the second relay, wherein the measurement indication information indicates the second relay to send the second measurement configuration and the second measurement signal to the second terminal. And the second relay measures the quality of a first measurement signal received through the first source link according to the received first measurement configuration to obtain the quality of the first source link, and then reports a first measurement report corresponding to the first source link to the first terminal, wherein the first measurement report comprises the quality of the first source link.

The second relay sends a second measurement configuration and a second measurement signal to the second terminal according to the received measurement indication information, the second terminal measures the second measurement signal according to the second measurement configuration to obtain the quality of a second source link, and then the second terminal can report a second measurement report corresponding to the second source link to the second relay, and the second relay reports the second measurement report to the first terminal, wherein the second measurement report comprises the quality of the second source link. The content of the second measurement configuration may be the same as or different from the content of the first measurement configuration. The second measurement configuration may be sent by the first terminal to the second relay, which forwards to the second terminal. The second measurement configuration may also be generated by the second relay from the measurement indication information (e.g., generated from the measurement indication information and the first measurement configuration), thereby saving signaling overhead between the first terminal and the second relay. The second measurement signal is generated by a second relay and may be different from the first measurement signal.

The second relay may periodically report the first measurement report corresponding to the first source link to the first terminal, where the reporting period may be that the first terminal is configured to be configured by the second relay through the first measurement, or the second relay may report the first measurement report corresponding to the first source link to the first terminal after receiving the request message from the first terminal, or the second relay may report the first measurement report corresponding to the first source link to the first terminal when the quality of the first source link is less than a certain threshold. In the embodiments of the present application, the link quality participates in mathematical operations, including addition and subtraction operations or numerical comparison, etc., and it can be understood that a specific numerical value of a parameter characterizing the link quality participates in mathematical operations.

The second terminal may periodically report the second measurement report corresponding to the second source link to the second relay, where the reporting period may be configured by the second relay to the second terminal through the second measurement configuration, or the second terminal may report the second measurement report corresponding to the second source link to the second relay after receiving the request message from the second relay, or the second terminal may report the second measurement report corresponding to the second source link to the second relay if the quality of the second source link is less than a certain threshold.

In step 202, the first terminal determines the first relay as a target relay in case the first condition is satisfied.

Assuming that one or more relays are distributed around the first terminal, the second terminal, the relays may broadcast a notification message, which may be received by terminals located around the relays, for notifying the terminals located around the relays: the relay is provided with relay transmission capability and is located around the terminal that receives the notification message. In this application, around a device means within the coverage area of the device's signal. The notification message may be an announcement message from one or more relays described above, or a response message that one or more relays reply to the received solicitation message.

As one implementation, the first condition may include at least one of: the quality of the first source link is less than a first threshold and the quality of the second source link is less than a second threshold. Assuming that the first terminal receives the notification message from one or more relays, in this case, if the first terminal determines that the above-described first condition is satisfied, the first terminal may select, as a target relay, a first relay capable of providing the relay transmission service for the first terminal and the second terminal from the one or more relays. Here, the first relay is capable of providing a relay transmission service to the first terminal and the second terminal, which means that: the first relay supports relay transmission; meanwhile, the first relay is within the coverage of the signal of the first terminal and the coverage of the signal of the second terminal, and the first terminal and the second terminal can be understood to be within the coverage of the signal of the first relay.

As another implementation, the first condition may include: the difference between the quality of the first target link and the quality of the first source link is greater than or equal to a third threshold, and the difference between the quality of the second target link and the quality of the second source link is greater than or equal to the third threshold. The first target link is a link between the first terminal and the first relay, and the second target link is a link between the first relay and the second terminal.

The first terminal may acquire the quality of the link between itself and the relay and the quality of the link between the second terminal and the relay for the same relay located around itself in addition to the quality of the first source link and the quality of the second source link during the communication connection with the second terminal, and then the first terminal may select the first relay satisfying the first condition from one or more relays around itself as the target relay.

The quality of the link between the first terminal and a relay is determined after the first terminal measures the signal of the notification message from the relay. The quality of the link between the second terminal and a relay is determined by the second terminal measuring the signal of the notification message from the relay, and the second terminal may report the link quality to the first terminal via the second relay after obtaining the link quality.

The method of the first terminal to acquire the quality of the link between itself and the relay and the quality of the link between the second terminal and the relay for the same relay (e.g., the third relay) will be described below.

Mode 1

The first terminal may measure the quality of the signal of the notification message from the third relay after receiving the notification message from the third relay, thereby obtaining the quality of the link between itself and the third relay. After receiving the notification message from the third relay, the second terminal also measures the quality of the signal of the notification message from the third relay, thereby obtaining the quality of the link between itself and the third relay, and then, the second terminal reports a measurement report corresponding to the link between itself and the third relay to the first terminal, wherein the measurement report comprises the quality of the link and the identification of the third relay. It may be appreciated that the second terminal may report the measurement report to the first terminal through the second relay.

Mode 2

The first terminal may send a third measurement configuration to the second terminal, so as to instruct the second terminal to determine the quality of the link between itself and the relay after receiving the notification message from the relay, and upload a measurement report corresponding to the link to the first terminal. The third measurement configuration may configure the second terminal with at least one of the following information: the second terminal reports the period of the measurement report to the first terminal and the triggering condition of the measurement report to the first terminal. The trigger condition may be that the quality of the link between the second terminal and the relay is greater than a certain threshold. The second terminal reports a measurement report corresponding to a link between itself and a certain relay (e.g., a third relay) to the first terminal according to the third measurement configuration, wherein the measurement report includes the quality of the link and the identity of the relay. It may be appreciated that the first terminal may send the third measurement configuration to the second terminal through the second relay, and the second terminal may report the measurement report to the first terminal through the second relay.

The first terminal may measure the signal quality of the notification message from the third relay after receiving the notification message from the third relay, thereby obtaining the quality of the link between itself and the third relay. It is understood that the first relay may be some third relay.

As an implementation, the first terminal may send the third measurement configuration to the second terminal after receiving the notification message from the third relay. The third measurement configuration may include information about the measurement object. The related information of the measurement object may include an identification of a relay that transmits the notification message. The identity of the relay may be a layer two identity (layer-2identifier,L2 ID) used by the relay when sending the notification message. And the second terminal determines the signal quality of the notification message from the relay corresponding to the layer two identifier according to the received third measurement configuration, and then the second terminal determines the quality of the link between the second terminal and the relay after receiving the notification message from the relay.

In this case, the measurement report sent by the second terminal to the first terminal may not include the identifier of the relay, and the first terminal may default that the quality of the link in the measurement report is the same as the quality of the link measured by itself after receiving the notification message after receiving the measurement report.

By enabling the measurement configuration sent by the first terminal to the second terminal to include the identifier of the relay, the second terminal can be prevented from measuring the signal quality of the received notification message from other relays, so that the power consumed by the second terminal for measuring the signal quality of the notification message is saved, and the first terminal and the second terminal can be ensured to measure the notification message from the same relay.

As an implementation manner, the information about the measurement object may further include at least one of a cell identifier corresponding to a relay that transmits the notification message, carrier information for the relay operation, and a serving public land mobile network (public land mobile network, PLMN) of the relay. By including at least one of the cell identifier corresponding to the relay sending the notification message, the carrier information of the relay operation, and the serving PLMN of the relay in the third measurement configuration, the searching difficulty of the second terminal can be reduced when the second terminal searches for the relay according to the identifier of the relay included in the third measurement configuration.

Based on the method 200, when the quality of the first source link and/or the quality of the second source link is poor, or the quality of the first target link is better than the quality of the first source link and the quality of the second target link is better than the quality of the second source link, the first relay capable of providing relay transmission for the first terminal and the second terminal is determined as the target relay, in other words, the first terminal and the second terminal can communicate through the first relay later, so as to ensure the quality of communication between the first terminal and the second terminal.

Fig. 4 shows a schematic flow chart of another example method 400 of determining a target relay provided by an embodiment of the present application. Next, each step of the method 400 is described in detail.

In step 401, the first terminal obtains quality of an air interface link between the first terminal and the second terminal.

Assuming that a communication connection exists between the first terminal and the second terminal, for example, the first terminal is currently communicating with the second terminal through the air interface link in fig. 5, the first terminal may acquire the quality of the air interface link.

The first terminal sends a fourth measurement configuration and a fourth measurement signal to the second terminal, the second terminal measures the fourth measurement signal according to the fourth measurement configuration to obtain the quality of an air interface link between the first terminal and the second terminal, and then reports a measurement report corresponding to the air interface link to the first terminal, wherein the measurement report comprises the quality of the air interface link.

The second terminal may periodically report the measurement report corresponding to the air interface link to the first terminal, where the reporting period may be configured by the first terminal through the fourth measurement configuration to the second terminal, or the second terminal may report the measurement report corresponding to the air interface link to the first terminal after receiving the request message from the first terminal, or the second terminal may report the measurement report corresponding to the air interface link to the first terminal when the quality of the air interface link is less than a certain threshold.

In step 402, the first terminal determines the first relay as a target relay in case the first condition is satisfied.

Assuming that one or more relays are distributed around the first terminal, the second terminal, the relays may broadcast a notification message, which may be received by terminals located around the relays, for notifying the terminals located around the relays: the relay is provided with relay transmission capability and is located around the terminal that receives the notification message.

As one implementation, the first condition may include: the quality of the air interface link between the first terminal and the second terminal is less than a second threshold.

Assuming that the first terminal receives the notification message from one or more relays, in this case, if the first terminal determines that the above first condition is satisfied, the first terminal may select, from the one or more relays, a first relay capable of providing a relay transmission service for the first terminal, the second terminal as a target relay.

As another implementation, the first condition may include: the difference between the quality of the first target link and the quality of the air interface link is greater than or equal to a fourth threshold, and the difference between the quality of the second target link and the quality of the air interface link is greater than or equal to the fourth threshold. For the description of the first target link and the second target link, please refer to the related description in the method 200, and for brevity, the description is omitted here.

The first terminal may acquire the quality of a link between itself and the relay and the quality of a link between the second terminal and the relay for the same relay located around itself in addition to the quality of an air interface link between the first terminal and the second terminal during the communication connection with the second terminal, and then the first terminal may select the first relay satisfying the first condition from one or more relays around itself as the target relay. Regarding the method for the first terminal to obtain the quality of the link between itself and the relay and the quality of the link between the second terminal and the relay for the same relay, and the method for the first terminal to obtain the quality of the link between itself and a certain relay, the method for the second terminal to obtain the quality of the link between itself and a certain relay is referred to the related description in the method 200, and for brevity, will not be repeated here.

Based on the method 400, when the quality of the air interface link between the first terminal and the second terminal is poor, or the quality of the first target link is better than the quality of the air interface link, and the quality of the second target link is better than the quality of the air interface link, the first relay capable of providing relay transmission for the first terminal and the second terminal is determined as the target relay, in other words, the first terminal and the second terminal can communicate through the first relay later, so that the quality of communication between the first terminal and the second terminal can be ensured.

Fig. 6 is a schematic flow chart diagram of an example method 600 of wireless relay communication provided by an embodiment of the present application. Each step of the method 600 is described in detail below.

In step 601, a first terminal establishes a unicast connection with a first relay.

Assume that there is a communication connection between the first terminal and the second terminal, for example, the first terminal is currently communicating with the second terminal through the second relay in fig. 3, or the first terminal is currently communicating with the second terminal through the air interface link in fig. 5.

It is assumed that the first terminal determines the first relay as the target relay according to the aforementioned method of determining the target relay, and then the first terminal may establish a unicast connection with the first relay. .

Fig. 7 shows a schematic flow chart of the establishment of a unicast connection between two terminals, which are for ease of description denoted as terminal 1, terminal 2, respectively.

In the unicast connection establishment procedure, terminal 1 first sends a direct communication request (direct communication request, DCR) message to terminal 2. After receiving the DCR message from terminal 1, terminal 2 sends a direct connection security mode command (direct security mode command) message to terminal 1 requesting that a secure connection be established with terminal 1. Next, the terminal 1 transmits a direct connection security mode complete (direct security mode complete) message to the terminal 2. After receiving the direct connection security mode complete message, the terminal 2 transmits a direct connection accept (direct communication accept, DCA) message to the terminal 1. Up to this point, a unicast connection is established between terminal 1 and terminal 2.

The terminals 1 and 2 here may be the above-described first terminal, first relay, second relay, or second terminal. It should be understood that in the process of establishing a unicast connection between the first terminal and the first relay, the first terminal corresponds to the above-mentioned terminal 1, the above-mentioned steps performed by the terminal 1 are performed, the first relay corresponds to the above-mentioned terminal 2, and the above-mentioned steps performed by the terminal 2 are performed.

In step 602, the first terminal sends first indication information to the second terminal, where the first indication information indicates that a unicast connection is established between the second terminal and the first relay. Accordingly, the second terminal receives the first indication information from the first terminal.

For the scenario shown in fig. 3, the first terminal may transmit the first indication information to the second terminal through the second relay, in other words, the first terminal may transmit the first indication information to the second terminal through the first source link between itself and the second relay, and the second source link between the second relay and the second terminal. For the scenario shown in fig. 5, the first terminal may directly send the first indication information to the second terminal. The first indication information may carry a first identifier allocated by the first terminal for identifying the second terminal.

Step 603, establishing a unicast connection between the second terminal and the first relay.

And the second terminal establishes unicast connection with the first relay after receiving the first indication information from the first terminal.

As an implementation manner, after the second terminal receives the first indication information, if the first indication information carries the first identifier, the method 600 may further include step 604, where the second terminal sends the first identifier to the first relay. Accordingly, the first relay receives the first identification from the second terminal. The second terminal may send the first identity to the first relay during establishment of the unicast connection with the first relay. For example, the second terminal may transmit the first identity to the first relay through a DCR message transmitted to the first relay in the course of establishing a unicast connection with the first relay.

Alternatively, the second terminal may configure the first identity to the first relay through PC5-S signaling or PC5-RRC signaling after establishing the unicast connection with the first relay.

As another possible implementation, the method 600 may further include step 605, where the first terminal sends the first identification to the first relay. Accordingly, the first relay receives the first identification from the first terminal.

For example, the first terminal may send the first identifier to the first relay in the process of establishing the unicast connection with the first relay, e.g., the first terminal may send the first identifier to the first relay through the DCR message sent to the first relay in the process of establishing the unicast connection with the first relay.

For another example, the first terminal may configure the first identifier to the first relay through PC5 interface signaling (PC 5-S) or PC5-RRC signaling after establishing the unicast connection with the first relay. Wherein RRC is an acronym for radio resource control.

The first terminal sends the first identifier which is distributed by the first terminal and used for identifying the second terminal to the second terminal, and the first terminal sends the first identifier to the first relay, when the first relay subsequently receives the data from the first terminal, the second terminal can be determined to be the destination terminal of the data according to the first identifier sent together with the data. In other words, the first relay determines that the first target link is associated with the second target link, forwarding data from the first terminal to the second terminal; or when the first relay subsequently receives the data from the second terminal, the first terminal can be determined to be the target terminal according to the first identifier sent together with the data.

As another implementation, the method 600 may further include step 606, the second terminal sending to the first terminal a second identification of the second terminal, which may be a layer two identification of the second terminal used by the second terminal in establishing the unicast connection with the first relay. Accordingly, the first terminal receives the second identification from the second terminal.

For example, taking the scenario shown in fig. 3 as an example, the second terminal may send the second identifier of the second terminal to the first terminal through the second relay, in other words, the second terminal may send the second identifier of the second terminal to the first terminal through the second source link with the second relay and the first source link between the second relay and the first terminal.

The second terminal may send the second identifier to the first terminal after receiving the first indication information from the first terminal. Alternatively, the second terminal may send the second identification to the first terminal after establishing the unicast connection with the first relay.

The method 600 may further include step 607, after the first terminal receives the second identifier from the second terminal, sending the second identifier to the first relay.

Specifically, the first terminal may send the second identifier to the first relay in a process of establishing a unicast connection with the first relay, for example, the first terminal may send the second identifier to the first relay through a DCR message.

The second terminal firstly sends a layer two identifier of the second terminal for establishing unicast connection with the first relay to the first terminal, and then the first terminal sends the layer two identifier of the second terminal to the first relay. When the communication connection is established between the two terminals, the communication connection between the two terminals is identified by using the layer two identification of the source terminal and the layer two identification pair of the destination terminal. For example, when a communication connection is established between a first terminal and a second terminal, the communication connection is identified using a layer two identification pair of the first terminal and the second terminal. When the first relay subsequently receives the data from the first terminal, it may determine that the layer two identifier pair of the first terminal and the layer two identifier pair of the second terminal included in the data are used to identify a communication connection between the first terminal and the second terminal according to the source address (i.e., the layer two identifier of the first terminal) sent with the data, thereby determining that the second terminal is a destination terminal. Or when the first relay subsequently receives the data from the second terminal, the layer two identifier pair of the second terminal and the layer two identifier pair of the first terminal included in the data can be determined to be used for identifying the communication connection between the first terminal and the second terminal according to the source address (namely, the layer two identifier of the second terminal) sent along with the data, so that the first terminal is determined to be the destination terminal.

It should be understood that the first identifier may be sent to the first relay and the layer two identifier of the second terminal may be sent to the first relay, and when the subsequent first relay receives the data from the first terminal or the second terminal, the data may be forwarded to the first terminal or the second terminal according to the first identifier and the layer two identifier of the second terminal.

Fig. 8 is a schematic flow chart diagram of another example method 800 of wireless relay communication provided by an embodiment of the present application. Each step of method 800 is described in detail below.

In step 801, a first terminal establishes a unicast connection with a first relay. For a detailed description of step 801, please refer to the related description in step 601, and for brevity, the description is omitted here.

Step 802, a first terminal sends first indication information to a first relay, where the first indication information indicates that a unicast connection is established between the first relay and a second terminal. Accordingly, the first relay receives the first indication information from the first terminal.

For example, the first terminal may transmit first indication information to the first relay after the unicast connection is established with the first relay, so as to indicate the first relay to establish the unicast connection with the second terminal through the first indication information.

In step 803, a unicast connection is established between the first relay and the second terminal.

For the beneficial effects of establishing unicast connection between the first terminal, the first relay, and the second terminal, reference is made to the description related to the method 600, and for brevity, the description is omitted here.

As an implementation manner, the method 800 may further include step 805, where the second terminal sends, to the first terminal, a second identifier of the second terminal, where the second identifier of the second terminal may be a layer two identifier of the second terminal used when the second terminal establishes a unicast connection with the first relay. Accordingly, the first terminal receives a second identification of the second terminal from the second terminal. For a specific method for the second terminal to send the second identifier of the second terminal to the first terminal, please refer to the description in step 606, and for brevity, details are not repeated here.

As an implementation, step 804 may be further included before step 805, where the first terminal sends a request message to the second terminal, where the request message requests the second terminal to send the second identifier of the second terminal to the first terminal. Accordingly, the second terminal receives the request message from the first terminal.

Taking the scenario shown in fig. 3 as an example, the first terminal may send the request message to the second terminal through the second relay, in other words, the first terminal may send the request message to the second terminal through the first source link between itself and the second relay, and the second source link between the second relay and the second terminal.

And the second terminal sends a second identification of the second terminal to the second terminal through a second source link between the second terminal and the second relay and a first source link between the second relay and the second terminal according to the request message from the first terminal.

As an implementation manner, the method 800 may further include step 806, where the first terminal sends the second identifier of the second terminal to the first relay after receiving the second identifier from the second terminal. For a specific method for the first terminal to send the second identifier of the second terminal to the first relay, please refer to the description in step 607, and for brevity, details are not repeated here.

For the beneficial effect of the first terminal sending the layer two identifier of the second terminal to the first relay, please refer to the related description in the method 600, and for brevity, the description is omitted here.

Fig. 9 is a schematic flow chart diagram of another example method 900 of determining a target relay provided by an embodiment of the present application. Each step of method 900 is described in detail below.

In step 901, the second relay obtains the quality of the first source link and the quality of the second source link.

Assume that there is currently a communication connection between the first terminal and the second terminal, for example, that communication between the first terminal and the second terminal is currently performed through the second relay in fig. 3.

The second relay may acquire the quality of the first source link and the quality of the second source link.

Illustratively, the second relay may obtain the quality of the first source link and the quality of the second source link in the following manner.

The second relay sends a fifth measurement configuration and a fifth measurement signal to the first terminal, the first terminal measures the quality of the fifth measurement signal received through the first source link according to the received fifth measurement configuration to obtain the quality of the first source link, and then the first terminal reports a fifth measurement report corresponding to the first source link to the second relay, wherein the fifth measurement report comprises the quality of the first source link.

The second relay sends a sixth measurement configuration and a sixth measurement signal to the second terminal, the second terminal measures the quality of the sixth measurement signal received through the second source link according to the received sixth measurement configuration to obtain the quality of the second source link, and then the second terminal reports a sixth measurement report corresponding to the second source link to the second relay, wherein the sixth measurement report comprises the quality of the second source link.

The first terminal may periodically report a fifth measurement report corresponding to the first source link to the second relay, where the reporting period may be configured by the second relay to the first terminal through the fifth measurement configuration, or the first terminal may report the fifth measurement report corresponding to the first source link to the second relay after receiving a request message from the second relay, or the first terminal may report the fifth measurement report corresponding to the first source link to the second relay if the quality of the first source link is less than a certain threshold.

The second terminal may periodically report a sixth measurement report corresponding to the second source link to the second relay, where the reporting period may be configured by the second relay to the second terminal through the sixth measurement configuration, or the second terminal may report the sixth measurement report corresponding to the second source link to the second relay after receiving a request message from the second relay, or the second terminal may report the sixth measurement report corresponding to the second source link to the second relay if the quality of the second source link is less than a certain threshold.

In step 902, the second relay determines the first relay as the target relay if the first condition is satisfied.

As one implementation, the first condition may include: the difference between the quality of the first target link and the quality of the first source link is greater than or equal to a third threshold, and the difference between the quality of the second target link and the quality of the second source link is greater than or equal to the third threshold. For the description of the first target link and the second target link, please refer to the related description in the method 200, and for brevity, the description is omitted here.

The second relay may acquire the quality of the link between the first terminal and the relay and the quality of the link between the second terminal and the relay for the same relay located around the first terminal and the second terminal in addition to acquiring the quality of the first source link and the quality of the second source link during the communication connection with the second terminal, and then the second relay may select the first relay satisfying the first condition from one or more relays around the first terminal and the second terminal as the target relay.

The method of the second relay to acquire the quality of the link between the first terminal and the relay and the quality of the link between the second terminal and the relay for the same relay (e.g., a third relay) located around the first terminal and the second terminal is described below.

The second relay may send a seventh measurement configuration to the first terminal to instruct the first terminal to determine the quality of the link between itself and the relay after receiving the notification message from the relay, and report a measurement report corresponding to the link to the second relay. The seventh measurement configuration may configure the first terminal with at least one of the following information: the first terminal reports the period of the measurement report to the second relay and the first terminal reports the triggering condition of the measurement report to the second relay. The trigger condition may be that the quality of the link between the first terminal and the relay is greater than a certain threshold. The first terminal reports a measurement report corresponding to a link between itself and a certain relay (for example, a third relay) to the second relay according to the seventh measurement configuration, wherein the measurement report comprises the quality of the link and the identification of the relay.

The second relay may send an eighth measurement configuration to the second terminal to instruct the second terminal to determine the quality of the link between itself and the relay after receiving the notification message from the relay, and report the measurement report corresponding to the link to the second relay. The eighth measurement configuration may configure the second terminal with at least one of the following information: the second terminal reports the period of the measurement report to the second relay and the triggering condition of the measurement report to the second relay. The trigger condition may be that the quality of the link between the second terminal and the relay is greater than a certain threshold. The second terminal reports a measurement report corresponding to a link between itself and a certain relay (for example, a third relay) to the second relay according to the eighth measurement configuration, wherein the measurement report comprises the quality of the link and the identification of the relay.

. Regarding the method for the first terminal to obtain the quality of the link between itself and a certain relay, the method for the second terminal to obtain the quality of the link between itself and a certain relay is referred to the related description in the method 200, and is not repeated here for brevity.

The second relay may determine the quality of the link from the first terminal and the quality of the link from the second terminal corresponding to the same identifier as the quality of the link between the first terminal, the second terminal and the same relay, respectively, according to the identifier of the relay included in the measurement report from the first terminal and the identifier of the relay included in the measurement report from the second terminal.

Based on the method 900, the second relay determines the first relay corresponding to the first target link and the second target link as the target relay when the quality of the first target link is better than the quality of the first source link and the quality of the second target link is better than the quality of the second source link, in other words, the first terminal and the second terminal communicate with each other through the first relay later, so as to ensure the quality of the communication between the first terminal and the second terminal.

Fig. 10 is a schematic flow chart of another example of a method 1000 of wireless relay communication provided by an embodiment of the present application. Each step of method 1000 is described in detail below.

In step 1001, the second relay sends second indication information to the first terminal, where the second indication information indicates that the first terminal establishes a unicast connection with the first relay. Accordingly, the first terminal receives the second indication information from the second relay.

Assuming that the second relay determines the first relay as the target relay according to the aforementioned method of determining the target relay, then the second relay may instruct the first terminal, the second terminal, and the first relay to establish unicast connection, respectively. For a specific description of the first condition and determining whether the first condition is satisfied, please refer to the related description in the method 200 or the method 400, and for brevity, the description is omitted here.

In step 1002, a first terminal establishes a unicast connection with a first relay.

In step 1003, the second relay sends third indication information to the second terminal, where the third indication information indicates that the second terminal establishes a unicast connection with the first relay. Accordingly, the second terminal receives the third indication information from the second relay.

In step 1004, the second terminal establishes a unicast connection with the first relay.

As an implementation, the method 1000 may further include steps 1005 to 1010:

in step 1005, the first terminal sends a second identifier of the first terminal to the second relay, where the second identifier is a layer two identifier of the first terminal used by the first terminal when establishing a unicast connection with the first relay. Accordingly, the second relay receives the second identification of the first terminal from the first terminal.

In step 1006, the second relay transmits the second identification of the first terminal to the second terminal. Accordingly, the second terminal receives the second identification from the first terminal of the second relay.

Step 1007, the second terminal sends the second identification of the first terminal to the first relay. Accordingly, the first relay receives the second identification of the first terminal from the second terminal.

The first terminal sends a layer two identifier of the first terminal for establishing unicast connection with the first relay to the second relay, the second relay sends the layer two identifier of the first terminal to the second terminal, and the second terminal sends the layer two identifier of the first terminal to the first relay. When a communication connection is established between two terminals, a layer two identifier of a source terminal and a layer two identifier pair of a destination terminal are used for identifying the communication connection between the two terminals, for example, when the communication connection is established between a first terminal and a second terminal, the layer two identifier pair of the first terminal and the layer two identifier pair of the second terminal are used for identifying the communication connection, and when the first relay subsequently receives data from the first terminal, the layer two identifier pair of the first terminal and the layer two identifier pair of the second terminal included in the data can be determined according to a source address (namely the layer two identifier of the first terminal) sent together with the data, so that the communication connection between the first terminal and the second terminal is identified, and the second terminal is determined to be the destination terminal. Or when the first relay subsequently receives the data from the second terminal, the layer two identifier pair of the second terminal and the layer two identifier pair of the first terminal included in the data can be determined to be used for identifying the communication connection between the first terminal and the second terminal according to the source address (namely, the layer two identifier of the second terminal) sent along with the data, so that the first terminal is determined to be the destination terminal.

Step 1008, the second terminal sends to the second relay a second identifier of the second terminal, the second identifier being a layer two identifier of the second terminal used by the second terminal when establishing a unicast connection with the first relay. Accordingly, the second relay receives a second identification of the second terminal from the second terminal.

In step 1009, the second relay transmits the second identification of the second terminal to the first terminal. Accordingly, the first terminal receives a second identification of the second terminal from the second relay.

In step 1010, the first terminal sends a second identification of the second terminal to the first relay. Accordingly, the first relay receives the second identification of the second terminal from the first terminal.

The second terminal sends a layer two identifier of the second terminal for establishing unicast connection with the first relay to the second relay, the second relay sends the layer two identifier of the second terminal to the first terminal, and the first terminal sends the layer two identifier of the second terminal to the first relay. The layer two identification pair used when establishing a communication connection between two terminals identifies the communication connection between the two terminals. For example, when a communication connection is established between the first terminal and the second terminal, the communication connection is identified by using a layer two identification pair of the first terminal and a layer two identification pair of the second terminal, and when the first relay subsequently receives data from the first terminal, the layer two identification pair of the first terminal and the layer two identification pair of the second terminal included in the data can be determined according to a destination address (i.e., the layer two identification of the second terminal) sent with the data, so that the communication connection between the first terminal and the second terminal is identified, and the second terminal is determined to be the destination terminal. Alternatively, when the first relay subsequently receives the data from the second terminal, it may determine that the layer two identification pair of the second terminal and the layer two identification pair of the first terminal included in the data is used to identify the communication connection between the first terminal and the second terminal according to the source address (i.e., the layer two identification of the second terminal) transmitted with the data, thereby determining that the first terminal is the destination terminal.

Fig. 11 is a schematic flow chart diagram of another example of a method 1100 of wireless relay communication provided by an embodiment of the present application. Each step of method 1100 is described in detail below.

In step 1101, the first terminal broadcasts a DCR message requesting the second terminal to reselect a relay and establish a unicast connection with the first terminal through the reselected relay.

The first terminal communicates with the second terminal via the second relay in fig. 3, assuming that a radio link failure (radio link failure, RLF) occurs in the first source link and/or the second source link between the first terminal and the second relay, in which case the first terminal may broadcast a DCR message for the second terminal to request the second terminal to reselect one relay in order to be able to continue communicating with the second terminal, thereby communicating with the second terminal via the reselected relay. It should be noted that "DCR message for the second terminal" may be understood as: the DCR message carries user information of the second terminal.

Assuming that there are one or more relays around the second terminal, in which case the first terminal may be received by the one or more relays, the one or more relays may assist the first terminal in broadcasting the DCR message, and when the second terminal receives the DCR message, it may determine that the DCR message is sent to itself according to the user information of the second terminal carried by the DCR message, in other words, the second terminal determines that the first terminal is to establish a unicast connection with itself.

Optionally, as an implementation manner, the DCR message carries indication information (Relay re-selection indication) of the reselection Relay, where the indication information instructs the second terminal to reselect one Relay.

After receiving the DCR message, the second terminal may select one relay from one or more relays around as a relay for subsequent communication with the first terminal according to the indication of the DCR message, for example, the second terminal may acquire, for the same relay, the quality of the link between itself and the relay and the quality of the link between the first terminal and the relay, and select, as a relay for subsequent communication with the first terminal, one relay from one or more relays around according to the quality of the link between itself and the first terminal and the same relay, respectively. For a specific method for determining that the second terminal provides a relay for the relay transmission with the first terminal, please refer to the foregoing related description, and for brevity, a detailed description is omitted herein.

In step 1102, the second terminal sends a DCA message to the first terminal, the DCA message indicating that the second terminal has completed establishment of the unicast connection with the first terminal.

After determining the relay, and after establishing a secure connection with the first terminal, the second terminal may send a DCA message to the first terminal to indicate to the first terminal: the second terminal has completed the establishment of the unicast connection with the first terminal.

It should be appreciated that the method 100 is equally applicable in situations where the source link between the first terminal and the second terminal is an air interface link.

It should also be understood that the DCR message broadcast by the first terminal may also be received directly by the second terminal, in which case the second terminal may re-determine an air interface link between itself and the first terminal according to the indication of the DCR message, and subsequently communicate with the first terminal via the link.

Based on the method 1100, the first terminal broadcasts a DCR capable of instructing the second terminal to reselect a relay, which may enable the second terminal to receive the DCR in the case that RLF occurs in the source link, and may reselect a relay capable of providing relay transmission for the first terminal and the second terminal according to the DCR instruction, so as to ensure normal communication between the first terminal and the second terminal.

It should be noted that, in the method for establishing a unicast connection provided in the embodiment of the present application, after a unicast connection is established between the first terminal and the first relay, and it is determined that a unicast connection is also established between the second terminal and the first relay, in one implementation manner, the first terminal may send a unicast connection release message to the second relay, so as to release the first source link; in another implementation, the first terminal may not release the first source link.

After establishing a unicast connection between the second terminal and the first relay and determining that a unicast connection is also established between the first terminal and the first relay, in one implementation, the second terminal may send a unicast connection release message to the second relay, thereby releasing the second source link; in another implementation, the second terminal may not release the second source link.

It should be noted that a case where the first source link and the second source link are released may be referred to as a link switch (path switch), and a case where the first source link and the second source link are not released may be referred to as a multi-link (multi-path).

It will be appreciated that, in order to implement the functions in the above embodiments, the terminal includes corresponding hardware structures and/or software modules for performing the respective functions. Those of skill in the art will readily appreciate that the elements and method steps of the examples described in connection with the embodiments disclosed herein may be implemented as hardware or a combination of hardware and computer software. Whether a function is implemented as hardware or computer software driven hardware depends upon the particular application scenario and design constraints imposed on the solution.

Fig. 12 and 13 are schematic structural diagrams of possible communication devices according to embodiments of the present application. These communication devices may be used to implement the functions of the terminal or relay in the above-described method embodiments, and thus may also implement the advantages provided by the above-described method embodiments. In the embodiment of the present application, the communication device may be one of the terminals 101-103 as shown in fig. 1, or may be a module (e.g. a chip) applied to the terminal.

As shown in fig. 12, in one implementation, the communication apparatus 1200 includes a processing unit 1210 and a transceiving unit 1220. The communication device 1200 is configured to implement the functions of the terminal in the method embodiments shown in fig. 2, fig. 4, and fig. 6 to fig. 11.

When the communication device 1200 is used to implement the functionality of the first terminal in the method embodiment shown in fig. 2: the processing unit 1210 is configured to obtain a quality of the first source link and a quality of the second source link, and determine the first relay as the target relay when the first condition is satisfied.

For more details regarding the above-mentioned processing unit 1210, reference is made to the relevant description in the method embodiment shown in fig. 2.

When the communication device 1200 is used to implement the functionality of the first terminal in the method embodiment shown in fig. 4: the processing unit 1210 is configured to obtain quality of an air interface link between the first terminal and the second terminal, and determine the first relay as the target relay when the first condition is satisfied.

For more details regarding the above-mentioned processing unit 1210, reference is made to the relevant description in the method embodiment shown in fig. 4.

When the communication apparatus 1200 is used to implement the functionality of the first terminal in the method embodiment shown in fig. 6: the processing unit 1210 is configured to establish a unicast connection with the first relay; the transceiver 1220 is configured to send first indication information to the second terminal, where the first indication information indicates that a unicast connection is established between the second terminal and the first relay.

For a more detailed description of the processing unit 1210 and the transceiver unit 1220, reference is made to the description related to the method embodiment shown in fig. 6.

When the communication apparatus 1200 is used to implement the functionality of the second terminal in the method embodiment shown in fig. 6: the transceiver 1220 is configured to receive first indication information from a first terminal, where the first indication information indicates that a unicast connection is established between a second terminal and a first relay; the processing unit 1210 is configured to establish a unicast connection with the first relay.

When the communication apparatus 1200 is used to implement the function of the first terminal in the method embodiment shown in fig. 8: the processing unit 1210 is configured to establish a unicast connection with the first relay; the transceiver 1220 is configured to send first indication information to the first relay, where the first indication information indicates that a unicast connection is established between the first relay and the second terminal.

For a more detailed description of the processing unit 1210 and the transceiver unit 1220, reference is made to the description of the method embodiment shown in fig. 8.

When the communication apparatus 1200 is used to implement the function of the first relay in the method embodiment shown in fig. 8: the transceiver 1220 is configured to receive first indication information from a first terminal, where the first indication information indicates that a unicast connection is established between the first relay and a second terminal; the processing unit 1210 is configured to establish a unicast connection with the second terminal.

When the communication apparatus 1200 is used to implement the function of the second relay in the method embodiment shown in fig. 9: the processing unit 1210 is configured to obtain a quality of the first source link and a quality of the second source link, and determine the first relay as the target relay when the first condition is satisfied.

For a more detailed description of the processing unit 1210, reference is made to the relevant description of the method embodiment shown in fig. 9.

When the communication apparatus 1200 is used to implement the function of the second relay in the method embodiment shown in fig. 10: the transceiver 1220 is configured to send second indication information to the first terminal, where the second indication information indicates that the first terminal establishes a unicast connection with the first relay, and send third indication information to the second terminal, where the third indication information indicates that the second terminal establishes a unicast connection with the first relay; the processing unit 1210 is configured to establish a unicast connection with the second terminal.

For a more detailed description of the processing unit 1210 and the transceiver unit 1220, reference is made to the description of the method embodiment shown in fig. 10.

When the communication apparatus 1200 is used to implement the function of the first terminal in the method embodiment shown in fig. 10: the transceiver 1220 is configured to receive second indication information from the second relay, where the second indication information indicates that the first terminal establishes a unicast connection with the first relay; the processing unit 1210 is configured to establish a unicast connection with the first relay.

When the communication apparatus 1200 is used to implement the function of the second terminal in the method embodiment shown in fig. 10: the transceiver 1220 is configured to receive third indication information from the second relay, where the third indication information indicates that the second terminal establishes unicast connection with the first relay; the processing unit 1210 is configured to establish a unicast connection with the first relay.

When the communication apparatus 1200 is used to implement the function of the first terminal in the method embodiment shown in fig. 11: the transceiver unit 1220 is configured to broadcast a DCR message, where the DCR message requests the second terminal to reselect a relay, and establish a unicast connection with the first terminal through the relay, and is further configured to receive a DCA message from the second terminal, where the DCA message indicates that the second terminal has completed establishment of a unicast connection with the first terminal.

For a more detailed description of the processing unit 1210 and the transceiver unit 1220, reference is made to the description of the method embodiment shown in fig. 11.

When the communication apparatus 1200 is used to implement the function of the second terminal in the method embodiment shown in fig. 11: the transceiver 1220 receives a DCR message from the first terminal, where the DCR message requests the second terminal to reselect a relay, and establishes a unicast connection with the first terminal through the relay, and is further configured to send a DCA message to the first terminal, where the DCA message indicates that the second terminal has completed establishment of the unicast connection with the first terminal.

As shown in fig. 13, communication device 1300 includes a processor 1310 and an interface circuit 1320. Processor 1310 and interface circuit 1320 are coupled to each other. It is understood that the interface circuit 1320 may be a transceiver or an input-output interface. Optionally, the communications device 1300 may also include a memory 1330 for storing instructions executed by the processor 1310 or for storing input data required by the processor 1310 to execute instructions or for storing data generated after the processor 1310 executes instructions.

When the communications apparatus 1300 is used to implement the method illustrated in fig. 2, the processor 1310 is configured to implement the functions of the processing unit 1210 described above.

When the communications apparatus 1300 is used to implement the method illustrated in fig. 4, the processor 1310 is configured to implement the functions of the processing unit 1210 described above.

When the communication apparatus 1300 is used for implementing the method shown in fig. 6, the processor 1310 is used for implementing the functions of the processing unit 1210, and the interface circuit 1320 is used for implementing the functions of the transceiver unit 1220.

When the communication apparatus 1300 is used for implementing the method shown in fig. 8, the processor 1310 is used for implementing the functions of the processing unit 1210, and the interface circuit 1320 is used for implementing the functions of the transceiver unit 1220.

When the communications apparatus 1300 is used to implement the method illustrated in fig. 9, the processor 1310 is configured to implement the functions of the processing unit 1210 described above.

When the communication apparatus 1300 is used for implementing the method shown in fig. 10, the processor 1310 is used for implementing the functions of the processing unit 1210, and the interface circuit 1320 is used for implementing the functions of the transceiver unit 1220.

When the communication apparatus 1300 is used to implement the method shown in fig. 11, the interface circuit 1320 is used to implement the functions of the transceiver unit 1220 described above.

When the communication device is a chip applied to the terminal, the terminal chip realizes the functions of the terminal in the embodiment of the method. The terminal chip receives information from other modules (such as a radio frequency module or an antenna) in the terminal, and the information is sent to the terminal by other terminals; alternatively, the terminal chip sends information to other modules (e.g., radio frequency modules or antennas) in the terminal, which the terminal sends to other terminals.

It is to be appreciated that 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), field programmable gate arrays (Field Programmable Gate Array, FPGA) or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. The general purpose processor may be a microprocessor, but in the alternative, it may be any conventional processor.

The method steps in the embodiments of the present application may be implemented in hardware, or in software instructions executable by a processor. The software instructions may be comprised of corresponding software modules that may be stored in random access memory, flash memory, read only memory, programmable read only memory, erasable programmable read only memory, electrically erasable programmable read only memory, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. The storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. In addition, the ASIC may reside in a terminal. The processor and the storage medium may reside as discrete components in a terminal.

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 programs or instructions. When the computer program or instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present application are performed in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, a network device, a user device, or other programmable apparatus. The computer program or 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 program or instructions may be transmitted from one website site, computer, server, or data center to another website site, computer, server, or data center by wired or wireless means. 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 integrates one or more available media. The usable medium may be a magnetic medium, e.g., floppy disk, hard disk, tape; but also optical media such as digital video discs; but also semiconductor media such as solid state disks. The computer readable storage medium may be volatile or nonvolatile storage medium, or may include both volatile and nonvolatile types of storage medium.

In various embodiments of the present application, terms and/or descriptions between the various embodiments are consistent and may reference each other if not specifically stated or logically conflicting, and technical features in the various embodiments may be combined to form new embodiments based on their inherent logical relationship.

In the embodiments of the present application, "at least one" means one or more, and "a plurality" means two or more. "and/or", describes an association relationship of an association object, and indicates that there may be three relationships, for example, a and/or B, and may indicate: a alone, a and B together, and B alone, wherein a, B may be singular or plural. In the text descriptions of the embodiments of the present application, the character "/", generally indicates that the associated objects are an "or" relationship; in the formulas of the embodiments of the present application, the character "/" indicates that the front-rear associated object is a "division" relationship. "including at least one of A, B and C" may mean: comprises A; comprises B; comprising C; comprises A and B; comprises A and C; comprises B and C; including A, B and C.

It will be appreciated that the various numerical numbers referred to in the embodiments of the present application are merely for ease of description and are not intended to limit the scope of the embodiments of the present application. The sequence number of each process does not mean the sequence of the execution sequence, and the execution sequence of each process should be determined according to the function and the internal logic.

Claims

1. A wireless relay communication method performed by a first terminal or a module applied to the first terminal, comprising:

acquiring the quality of a source link, wherein the source link comprises an air interface link between the first terminal and the second terminal, or comprises a first source link and a second source link, the first source link is an air interface link between the first terminal and a second relay, and the second source link is an air interface link between the second relay and the second terminal;

when a first condition is met, unicast connection is established with a first relay, wherein the first relay is a terminal capable of providing relay transmission for the first terminal and the second terminal;

and sending first indication information to the second terminal, wherein the first indication information indicates that unicast connection is established between the second terminal and the first relay, or sending first indication information to the first relay indicates that unicast connection is established between the first relay and the second terminal.

2. The method of claim 1, wherein the first condition comprises at least one of: the quality of the first source link is less than a first threshold and the quality of the second source link is less than the first threshold.

3. The method of claim 1, wherein the first condition comprises: the quality of the air interface link between the first terminal and the second terminal is less than a second threshold.

4. The method of claim 1, wherein the first condition comprises: the difference between the quality of the first target link and the quality of the first source link is greater than or equal to a third threshold, and the difference between the quality of the second target link and the quality of the second source link is greater than or equal to the third threshold, wherein the first target link is an air interface link between the first terminal and the first relay, and the second target link is an air interface link between the first relay and the second terminal.

5. The method of claim 1, wherein the first condition comprises: the difference between the quality of the first target link and the quality of the air interface link is greater than or equal to a fourth threshold, and the difference between the quality of the second target link and the quality of the air interface link is greater than or equal to the fourth threshold, the first target link being an air interface link between the first terminal and the first relay, the second target link being an air interface link between the first relay and the second terminal.

6. The method according to any of claims 1 to 5, wherein the first indication information carries a first identification allocated by the first terminal for identifying the second terminal.

7. The method of claim 6, the method further comprising:

and sending the first identification to the first relay.

8. The method according to any one of claims 1 to 7, further comprising:

receiving a second identifier from the second terminal, wherein the second identifier is a layer two identifier of the second terminal for establishing unicast connection with the first relay;

and sending the second identification to the first relay.

9. A communication method performed by a second terminal or a module applied to the second terminal, comprising:

receiving first indication information from a first terminal, wherein the first indication information indicates that unicast connection is established between the second terminal and a first relay, and the first relay is a terminal capable of providing relay transmission for the first terminal and the second terminal;

and establishing unicast connection with the first relay.

10. The method of claim 9, wherein the first indication information carries an identification allocated by the first terminal for identifying the second terminal.

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

and sending the first identification to the first relay.

12. The method according to any one of claims 9 to 11, further comprising:

and sending a second identifier of the second terminal to the first terminal, wherein the second identifier is a layer two identifier of the second terminal for establishing unicast connection with the first relay.

13. A communication method performed by a first relay or a module applied to the first relay, the first relay being a terminal capable of providing relay transmission for a first terminal and a second terminal, comprising:

receiving first indication information from the first terminal, wherein the first indication information indicates that unicast connection is established between the first relay and the second terminal;

and establishing unicast connection with the second terminal.

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

and receiving a second identifier of the second terminal from the first terminal, wherein the second identifier is a layer two identifier of the second terminal for establishing unicast connection with the first relay.

15. A communication device comprising a processor and interface circuitry for receiving signals from other communication devices and transmitting to the processor or sending signals from the processor to other communication devices, the processor being configured to implement the method of any one of claims 1 to 8, or to implement the method of any one of claims 9 to 12, or to implement the method of claim 13 or 14, by logic circuitry or execution of code instructions.

16. A computer readable storage medium, characterized in that the storage medium has stored therein a computer program or instructions which, when executed by a communication device, implements the method of any one of claims 1 to 8, or implements the method of any one of claims 9 to 12, or implements the method of claim 13 or 14.