CN109803340B

CN109803340B - Message transmission method, user equipment, base station and computer readable storage medium

Info

Publication number: CN109803340B
Application number: CN201711148128.2A
Authority: CN
Inventors: 张丽
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2017-11-17
Filing date: 2017-11-17
Publication date: 2022-02-15
Anticipated expiration: 2037-11-17
Also published as: CN109803340A; WO2019096293A1

Abstract

The application discloses a message transmission method, user equipment, a base station and a computer readable storage medium, wherein the message transmission method comprises the steps that the user equipment selects an uplink carrier, and sends a random access lead code to the base station on the selected uplink carrier; the method comprises the steps that user equipment receives a random access response message from a base station, wherein the random access response message comprises random access lead code identification information corresponding to the random access response message and uplink carrier identification information used for indicating the random access lead code corresponding to the random access response message; and the user equipment judges whether the random access response message is a random access response message corresponding to the random access lead code sent by the user equipment according to the random access lead code identification information and the uplink carrier identification information. The method and the device improve the success rate of random access by adding the uplink carrier identification information into the random access response message.

Description

Message transmission method, user equipment, base station and computer readable storage medium

Technical Field

The present invention relates to the field of wireless communication technologies, and in particular, to a message transmission method, a user equipment, a base station, and a computer-readable storage medium.

Background

The New Radio (NR) 5G is an ongoing research Project of the third Generation Partnership (3 GPP), which determines a New Radio air interface standard based on Orthogonal Frequency Division Multiplexing (OFDM) and will be the basis of the next Generation mobile networks. In the current discussion process of the 5G standard, a scenario that a cell has only one uplink carrier and one downlink carrier is mainly considered, and for a cell random access process in the scenario, because only one uplink carrier and one downlink carrier exist, a carrier selection process does not exist, and the problem of random access failure caused by carrier selection failure is avoided.

However, when there are a plurality of uplink carriers in a cell, in this case, there are some uplink carriers corresponding to downlink carriers and some uplink carriers not corresponding to downlink carriers, and for example, it is assumed that 2 uplink carriers are configured on the network side: f1, F2, and 1 downlink carrier F3, where F2 and F3 are corresponding uplink and downlink carriers, respectively, and F2 and F3 may be Paired (Paired) or Unpaired (Unpaired), there is no corresponding downlink carrier in F1, and both uplink carriers F1 and F2 are configured with Random Access Channel (RACH) resources and Physical Random Access Channel (PRACH) resources. After the random access is triggered, according to the principle of carrier selection, some User Equipments (UEs) select the uplink carrier F1 to send Preamble codes, and some UEs select the uplink carrier F2 to send Preamble codes. According to a calculation method that only time-frequency resources are considered in a Random Access Radio Network Temporary Identity (RA-RNTI) in an existing Long Term Evolution (LTE) system, when Preamble codes of different UEs are transmitted on 2 uplink carriers, the calculated RA-RNTIs may be the same. For example, when 2 UEs select 2 different uplink carriers, but select the same time domain resource, and the corresponding frequency domain resources selected on the 2 uplink carriers are also the same, the Medium Access Control (MAC) layer Random Access Response (RAR) messages of the 2 UEs will use the same RA-RNTI. If the MAC RAR message in the 5G NR or subsequent Network only includes a Timing Advance Command (TAC), an Uplink (UL) grant (grant) and a Temporary (Temporary) Cell Radio Network Temporary Identifier (C-RNTI), and the preambles sent by 2 UEs are also the same, the MAC RAR messages of the 2 UEs cannot be distinguished. At this time, if one UE uses the MAC RAR Message of another UE, it is likely to cause the failure of Message 3(Message 3, Msg3) transmission. Therefore, in such a scenario with multiple uplink carriers, there is a problem how to distinguish whether or not the RAR Message (i.e., Message 2 (Msg 2)) is sent to the UE.

In addition, in a handover scenario, if the target cell has multiple uplink carriers, after the target base station receives the handover request message from the original base station, the target base station may select a suitable carrier and allocate a dedicated RACH resource on the carrier, and if the design of the LTE system is adopted, the dedicated RACH resource includes a dedicated Preamble code and a designated dedicated PRACH resource. The target base station transmits the dedicated RACH Resource to the original base station, and the original base station transmits the dedicated RACH Resource to the UE through a Radio Resource Control (RRC) message. After the UE receives the configuration message, the UE selects one carrier from the multiple uplink carriers in the common configuration message for access, and because the target base station does not indicate a carrier used by the dedicated RACH resource, the carrier selected by the UE may not be consistent with the carrier selected by the target base station, and at this time, random access failure is likely to be caused, and further handover failure is likely to be caused.

Disclosure of Invention

In order to solve the above technical problems, the present invention provides a message transmission method, a user equipment, a base station, and a computer-readable storage medium, which can improve the success rate of a random access procedure.

In order to achieve the purpose of the invention, the technical scheme of the embodiment of the invention is realized as follows:

the embodiment of the invention provides a message transmission method, which comprises the following steps:

the user equipment selects an uplink carrier, and sends a random access preamble to the base station on the selected uplink carrier;

the method comprises the steps that user equipment receives a random access response message from a base station, wherein the random access response message comprises random access lead code identification information corresponding to the random access response message and uplink carrier identification information used for indicating the random access lead code corresponding to the random access response message;

and the user equipment judges whether the random access response message is a random access response message corresponding to the random access lead code sent by the user equipment according to the random access lead code identification information and the uplink carrier identification information.

Further, the uplink carrier identification information is a carrier index number or a carrier name.

Further, the uplink carriers include a secondary uplink carrier and a non-secondary uplink carrier.

Further, the carrier index number of the non-assisted uplink carrier is smaller than the carrier index number of the assisted uplink carrier.

Further, the selecting, by the ue, an uplink carrier includes:

and the user equipment selects the uplink carrier according to the carrier selection threshold indicated by the base station.

The embodiment of the invention also provides a message transmission method, which comprises the following steps:

a base station receives a random access lead code from user equipment, and acquires identification information of the random access lead code and identification information of an uplink carrier bearing the random access lead code;

and the base station sends a random access response message to the user equipment, wherein the random access response message comprises the random access lead code identification information and the uplink carrier identification information.

the target base station receives a switching request message of an original base station to which user equipment belongs, selects an uplink carrier and selects a special random access channel resource on the uplink carrier;

and the target base station sends the uplink carrier identification information of the selected uplink carrier and the special random access channel resource to the original base station.

the original base station sends a switching request message to a target base station;

the original base station receives the uplink carrier identification information and the special random access channel resource from the target base station;

and the original base station sends the received uplink carrier identification information and the special random access channel resource to the user equipment.

the method comprises the steps that user equipment receives uplink carrier identification information and special random access channel resources from an original base station to which the user equipment belongs, wherein the special random access channel resources comprise special lead codes;

and the user equipment sends a special lead code to the target base station on the uplink carrier indicated by the uplink carrier identification information.

Embodiments of the present invention also provide a computer-readable storage medium storing one or more programs, which are executable by one or more processors to implement the steps of the message transmission method as described in any above.

The embodiment of the present invention further provides a user equipment, which includes a first sending module, a first receiving module and a judging module, wherein:

the first sending module is used for selecting an uplink carrier, sending a random access lead code to the base station on the selected uplink carrier, and outputting random access lead code identification information and uplink carrier identification information corresponding to the sent random access lead code to the judging module;

a first receiving module, configured to receive a random access response message from a base station, where the random access response message includes random access preamble identification information corresponding to the random access response message and uplink carrier identification information used to indicate a random access preamble corresponding to the random access response message, and output the random access preamble identification information and the uplink carrier identification information to a determining module;

and the judging module is used for receiving the random access lead code identification information and the uplink carrier identification information output by the first sending module and the first receiving module, and judging whether the random access response is a random access response message corresponding to the random access lead code sent by the first sending module according to the random access lead code identification information and the uplink carrier identification information.

The embodiment of the present invention further provides a base station, including a second receiving module and a second sending module, wherein:

a second receiving module, configured to receive a random access preamble from a user equipment, acquire random access preamble identification information and uplink carrier identification information carrying the random access preamble, and output the random access preamble identification information and the uplink carrier identification information to a second sending module;

and a second sending module, configured to receive the random access preamble identification information and the uplink carrier identification information output by the second receiving module, and send a random access response message to the user equipment, where the random access response message includes the random access preamble identification information and the uplink carrier identification information.

The embodiment of the present invention further provides a base station, which is used as a target base station for performing terminal handover, and includes a third receiving module and a third sending module, where:

a third receiving module, configured to receive a handover request message of an original base station to which the user equipment belongs, select an uplink carrier, select a dedicated random access channel resource on the uplink carrier, and output uplink carrier identification information of the selected uplink carrier and the dedicated random access channel resource to a third sending module;

and the third sending module is used for receiving the uplink carrier identification information and the special random access channel resource output by the third receiving module and sending the uplink carrier identification information and the special random access channel resource to the original base station to which the user equipment belongs.

The embodiment of the present invention further provides a base station, which is an original base station for performing terminal handover, and includes a fourth sending module and a fourth receiving module, where:

a fourth sending module, configured to send a handover request message to a target base station when it is determined that the ue needs to be handed over; receiving uplink carrier identification information and dedicated random access channel resources output by a fourth receiving module, and sending the uplink carrier identification information and the dedicated random access channel resources to user equipment;

and the fourth receiving module is used for receiving the uplink carrier identification information and the special random access channel resource from the target base station and outputting the uplink carrier identification information and the special random access channel resource to the fourth sending module.

The embodiment of the present invention further provides a user equipment, which includes a fifth receiving module and a fifth sending module, wherein:

a fifth receiving module, configured to receive uplink carrier identification information and a dedicated random access channel resource from an original base station to which a user equipment belongs, where the dedicated random access channel resource includes a dedicated preamble, and send the uplink carrier identification information and the dedicated random access channel resource to a fifth sending module;

and a fifth sending module, configured to receive the uplink carrier identifier information and the dedicated random access channel resource output by the fifth receiving module, and send a dedicated preamble to the target base station on the uplink carrier indicated by the uplink carrier identifier information.

The technical scheme of the invention has the following beneficial effects:

according to the message transmission method, the user equipment, the base station and the computer readable storage medium, the uplink carrier identification information is added into the MAC RAR, so that the user equipment can judge whether the received MAC RAR belongs to the MAC RAR of the user equipment according to the carrier in the MAC RAR under the condition that random access lead code identification information (RAPID) is the same, and the success rate of random access is improved;

furthermore, the success rate of switching is improved by adding the uplink carrier identification information into the switching indication.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:

fig. 1 is a flowchart illustrating a message transmission method according to a first embodiment of the present invention;

fig. 2 is a schematic diagram of a MAC RAR with a 1-bit carrier index field added according to an embodiment of the present invention;

fig. 3 is a schematic diagram of a MAC RAR with a 2-bit carrier index field added according to an embodiment of the present invention;

fig. 4 is a flowchart illustrating a message transmission method according to a second embodiment of the present invention;

fig. 5 is a flowchart illustrating a message transmission method according to a third embodiment of the present invention;

fig. 6 is a flowchart illustrating a message transmission method according to a fourth embodiment of the present invention;

fig. 7 is a flowchart illustrating a message transmission method according to a fifth embodiment of the present invention;

fig. 8 is a schematic structural diagram of a user equipment according to a first embodiment of the present invention;

fig. 9 is a schematic structural diagram of a base station according to a first embodiment of the present invention;

fig. 10 is a schematic structural diagram of a base station according to a second embodiment of the present invention;

fig. 11 is a schematic structural diagram of a base station according to a third embodiment of the present invention;

fig. 12 is a schematic structural diagram of a user equipment according to a second embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the embodiments and features of the embodiments in the present application may be arbitrarily combined with each other without conflict.

As shown in fig. 1, a message transmission method according to the present invention includes the following steps:

step 101: the user equipment selects an uplink carrier, and sends a random access preamble to the base station on the selected uplink carrier;

further, the user equipment selects the uplink carrier according to the carrier selection threshold indicated by the base station.

It should be noted that, the present invention emphasizes that the random access response message carries the uplink carrier identification information for indicating the random access preamble corresponding to the random access response message, and as for how the user equipment selects the uplink carrier according to the configuration threshold or other schemes, the present invention may be implemented by using an algorithm in the prior art, which is not limited by the present invention.

Step 102: the user equipment receives a random access response message from the base station, wherein the random access response message comprises random access lead code identification information corresponding to the random access response message and uplink carrier identification information used for indicating the random access lead code corresponding to the random access response message;

further, the uplink Carrier identification information is a Carrier Index (Carrier Index) or a Carrier name. And when the uplink carrier identification information is the carrier index number, the occupied bit number is shorter.

In an embodiment of the present invention, it is assumed that 2 uplink carriers exist in a cell in which a ue is located: f1 and F2, as shown in fig. 2, when the MAC RAR message is generated, the length of the Carrier Index introduced may be 1 bit, for example, the Index number of the F1 Carrier is 0, and the Index number of the F2 Carrier is 1. In another embodiment of the present invention, it is assumed that there are 4 uplink carriers in the cell where the ue is located: f1, F2, F3, and F4, as shown in fig. 3, when generating the MAC RAR message, the length of the Carrier Index introduced may be 2 bits, for example, the Index number of the F4 Carrier is 3, the Index number of the F3 Carrier is 2, the Index number of the F2 Carrier is 1, and the Index number of the F1 Carrier is 0.

It should be noted that whether the carrier indication field exists may be indicated by a reserved field (1 bit) in fig. 2 or 3, or by adding a new field, for example, a reserved field or a new added field of 0 means no carrier indication field, and a reserved field or a new added field of 1 means a carrier indication field. The existing cell has only one uplink carrier, and some cells have a plurality of uplink carriers, and the UE does not determine whether the message sent by the base station carries the carrier indication domain, so that the UE can analyze the content of the received message more quickly by reserving the field or adding a field indication message to determine whether the carrier indication domain is included in the message.

Further, the Uplink carriers include auxiliary Uplink (SUL) carriers and non-auxiliary Uplink (non-SUL) carriers.

Specifically, the carrier index number of the non-assisted uplink carrier may be greater than the carrier index number of the assisted uplink carrier, or may be smaller than the carrier index number of the assisted uplink carrier. Preferably, the carrier index number of the non-assisted uplink carrier is smaller than the carrier index number of the assisted uplink carrier.

In an embodiment of the present invention, it is assumed that 2 uplink carriers exist in a cell in which a ue is located: the SUL Carrier F1 and the non-SUL Carrier F2, when the MAC RAR message is generated, if the length of the Carrier Index introduced is 1 bit, the Index number of the F1 Carrier is 1, and the Index number of the F2 Carrier is 0.

Step 103: and the user equipment judges whether the random access response is a random access response message corresponding to the random access lead code sent by the user equipment according to the random access lead code identification information and the uplink carrier identification information.

Specifically, when the random access preamble identification information and the uplink carrier identification information in the random access response message are the same as the random access preamble identification information and the uplink carrier identification information sent by the user equipment, the user equipment judges that the random access response is the random access response message corresponding to the random access preamble sent by the user equipment, and sends a message 3(Msg3) at the indicated resource position; when the random access lead code identification information in the random access response message is inconsistent with the random access lead code identification information sent by the user equipment, or when the uplink carrier identification information in the random access response message is inconsistent with the uplink carrier identification information sent by the user equipment, the user equipment judges that the random access response is not the random access response message corresponding to the random access lead code sent by the user equipment.

As shown in fig. 4, an embodiment of the present invention further provides a message transmission method, including the following steps:

step 401: a base station receives a random access lead code from user equipment, and acquires identification information of the random access lead code and identification information of an uplink carrier bearing the random access lead code;

further, the uplink Carrier identification information is Carrier Index or Carrier name. And when the uplink Carrier identification information is Carrier Index, the occupied bit number is shorter.

In an embodiment of the present invention, it is assumed that 2 uplink carriers exist in a cell in which a ue is located: f1, F2, as shown in fig. 2, the length of the Carrier Index may be 1 bit, for example, the Index number of the F1 Carrier is 0, and the Index number of the F2 Carrier is 1.

In another embodiment of the present invention, it is assumed that there are 4 uplink carriers in the cell where the ue is located: f1, F2, F3, and F4, as shown in fig. 3, the length of the Carrier Index may be 2 bits, for example, the Index number of the F4 Carrier is 3, the Index number of the F3 Carrier is 2, the Index number of the F2 Carrier is 1, and the Index number of the F1 Carrier is 0.

Preferably, the carrier index number of the non-assisted uplink carrier is smaller than the carrier index number of the assisted uplink carrier.

Step 402: and the base station sends a random access response message to the user equipment, wherein the random access response message comprises random access lead code identification information and the uplink carrier identification information.

Specifically, after receiving the random access response message, the user equipment determines whether the random access response is a random access response message corresponding to the random access preamble sent by the user equipment according to the random access preamble identification information and the uplink carrier identification information in the random access response message.

As shown in fig. 5, an embodiment of the present invention further provides a message transmission method, including the following steps:

step 501: the target base station receives a switching request message of an original base station to which user equipment belongs, selects an uplink carrier and selects a special RACH resource on the uplink carrier;

it should be noted that the original base station to which the user equipment belongs selects the target base station according to the downlink measurement result of the neighboring cell, and transmits the handover request message to the target base station after the target base station is selected. If the target base station has a plurality of uplink carriers, the uplink carriers need to be selected after receiving the switching request message. When the target base station selects the uplink carrier, the selection can be considered according to the comparison between the downlink measurement result transmitted by the original base station and the preset threshold value, and the selection can also be considered according to the access reliability of the carrier; in addition, an appropriate uplink carrier may be selected according to the uplink signal of the original base station measured by the target base station.

Step 502: and the target base station transmits the uplink carrier identification information of the selected uplink carrier and the special RACH resource to the original base station.

Further, the target base station transmits the uplink carrier identification information of the selected uplink carrier and the dedicated RACH resource to the original base station through an X2, an eX2, or an Xn interface.

In an embodiment of the present invention, it is assumed that 2 uplink carriers exist in a cell in which a ue is located: f1 and F2, when the handover confirmation message is generated, the length of the Carrier Index introduced may be 1 bit, for example, the Index number of the F1 Carrier is 0, and the Index number of the F2 Carrier is 1.

In another embodiment of the present invention, it is assumed that there are 4 uplink carriers in the cell where the ue is located: f1, F2, F3, and F4, when the handover confirmation message is generated, the length of the Carrier Index introduced may be 2 bits, for example, the Index number of the F4 Carrier is 3, the Index number of the F3 Carrier is 2, the Index number of the F2 Carrier is 1, and the Index number of the F1 Carrier is 0.

It should be noted that, since the MAC RAR message has a specific format, and as shown in fig. 2 and fig. 3, there are 1 reserved fields in the existing RAR message, it can be indicated whether there is a carrier indication field through the reserved fields. For the handover process, a field of carrier index is added to the handover confirm message, and the field is defined as Optional (Optional). Further, the uplink carriers include SUL carriers and non-SUL carriers.

Preferably, the carrier index number of the non-SUL carrier is smaller than the carrier index number of the SUL carrier.

In an embodiment of the present invention, it is assumed that 2 uplink carriers exist in a cell in which a ue is located: the SUL Carrier F1 and the non-SUL Carrier F2, when the handover confirmation message is generated, if the length of the Carrier Index introduced is 1 bit, the Index number of the F1 Carrier is 1, and the Index number of the F2 Carrier is 0.

As shown in fig. 6, an embodiment of the present invention further provides a message transmission method, including the following steps:

step 601: the original base station sends a switching request message to a target base station;

it should be noted that the original base station to which the user equipment belongs selects the target base station according to the downlink measurement result of the neighboring cell, and transmits the handover request message to the target base station after the target base station is selected.

Step 602: the original base station receives the uplink carrier identification information and the special RACH resource from the target base station;

further, the original base station receives the uplink carrier identification information and the dedicated RACH resource from the target base station through an X2, an eX2, or an Xn interface.

In an embodiment of the present invention, it is assumed that 2 uplink carriers exist in a cell in which a ue is located: f1 and F2, as shown in fig. 2, when the handover confirm message is generated, the length of the Carrier Index introduced may be 1 bit, for example, the Index number of the F1 Carrier is 0, and the Index number of the F2 Carrier is 1.

Further, the uplink carriers include SUL carriers and non-SUL carriers.

Step 603: and the original base station sends the received uplink carrier identification information and the special RACH resource to the user equipment.

It should be noted that, after receiving the uplink carrier identification information and the dedicated RACH resource, the user equipment sends the dedicated Preamble code included in the dedicated RACH resource to the target base station on the selected uplink carrier.

Further, the original base station sends the received uplink carrier identification information and the dedicated RACH resource to the user equipment through a radio resource control message.

As shown in fig. 7, an embodiment of the present invention further provides a message transmission method, including:

step 701: the method comprises the steps that user equipment receives uplink carrier identification information and a special RACH resource from an original base station to which the user equipment belongs, wherein the special RACH resource comprises a special lead code;

further, the uplink carrier identification information of the original base station and the dedicated RACH resource are carried in the radio resource control message.

In an embodiment of the present invention, it is assumed that 2 uplink carriers exist in a cell in which a ue is located: f1 and F2, the length of the Carrier Index introduced in the rrc message may be 1 bit, for example, the Index number of the F1 Carrier is 0, and the Index number of the F2 Carrier is 1.

In another embodiment of the present invention, it is assumed that there are 4 uplink carriers in the cell where the ue is located: f1, F2, F3, and F4, the length of the Carrier Index introduced in the rrc message may be 2 bits, for example, the Index number of the F4 Carrier is 3, the Index number of the F3 Carrier is 2, the Index number of the F2 Carrier is 1, and the Index number of the F1 Carrier is 0.

Further, the uplink carriers include SUL carriers and non-SUL carriers.

In an embodiment of the present invention, it is assumed that 2 uplink carriers exist in a cell in which a ue is located: the SUL Carrier F1 and the non-SUL Carrier F2 assume that the length of the Carrier Index introduced in the switching confirmation message is 1 bit, and then the Index number of the F1 Carrier is 1, and the Index number of the F2 Carrier is 0.

Step 702: and the user equipment sends the special lead code to the target base station on the uplink carrier indicated by the uplink carrier identification information.

It should be noted that, after receiving the dedicated preamble, the target base station generates a MAC RAR message and sends the MAC RAR message to the user equipment.

As shown in fig. 8, an embodiment of the present invention further provides a user equipment, which includes a first sending module 801, a first receiving module 802, and a determining module 803, where:

a first sending module 801, configured to select an uplink carrier, send a random access preamble to a base station on the selected uplink carrier, and output random access preamble identification information and uplink carrier identification information corresponding to the sent random access preamble to a determining module 803;

a first receiving module 802, configured to receive a random access response message from a base station, where the random access response message includes random access preamble identification information corresponding to the random access response message and uplink carrier identification information used to indicate a random access preamble corresponding to the random access response message, and output the random access preamble identification information and the uplink carrier identification information to a determining module 803;

the determining module 803 is configured to receive the random access preamble identification information and the uplink carrier identification information output by the first sending module 801 and the first receiving module 802, and determine whether the random access response is a random access response message corresponding to the random access preamble sent by the first sending module 801 according to the random access preamble identification information and the uplink carrier identification information.

Further, the first sending module 801 selects an uplink carrier according to a carrier selection threshold indicated by the base station.

It should be noted that, the present invention emphasizes that the random access response message carries uplink carrier identification information for indicating the random access preamble corresponding to the random access response message, and as for how the first sending module 801 selects the uplink carrier according to the configuration threshold or other schemes, the algorithm in the prior art may be implemented, and the present invention is not limited to this.

Further, the uplink Carrier identification information is a Carrier Index (Carrier Index) or a Carrier name. And when the uplink Carrier identification information is Carrier Index, the occupied bit number is shorter.

As shown in fig. 9, an embodiment of the present invention further provides a base station, including a second receiving module 901 and a second sending module 902, where:

a second receiving module 901, configured to receive a random access preamble from a user equipment, acquire random access preamble identification information and uplink carrier identification information carrying the random access preamble, and output the random access preamble identification information and the uplink carrier identification information to a second sending module 902;

a second sending module 902, configured to receive the random access preamble identification information and the uplink carrier identification information output by the second receiving module 901, and send a random access response message to the user equipment, where the random access response message includes the random access preamble identification information and the uplink carrier identification information.

As shown in fig. 10, an embodiment of the present invention further provides a base station, as a target base station for performing terminal handover, including a third receiving module 1001 and a third sending module 1002, where:

a third receiving module 1001, configured to receive a handover request message of an original base station to which a user equipment belongs, select an uplink carrier, select a dedicated RACH resource on the uplink carrier, and output uplink carrier identification information of the selected uplink carrier and the dedicated RACH resource to a third sending module 1002;

a third sending module 1002, configured to receive the uplink carrier identifier information and the dedicated RACH resource output by the third receiving module 1001, and send the uplink carrier identifier information and the dedicated RACH resource to an original base station to which the user equipment belongs.

Further, the uplink carriers include SUL carriers and non-SUL carriers.

As shown in fig. 11, an embodiment of the present invention further provides a base station, which is an original base station for performing terminal handover, and includes a fourth sending module 1101 and a fourth receiving module 1102, where:

a fourth sending module 1101, configured to send a handover request message to a target base station when it is determined that the ue needs to be handed over; receiving the uplink carrier identification information and the dedicated RACH resource output by the fourth receiving module 1102, and sending the uplink carrier identification information and the dedicated RACH resource to the user equipment;

a fourth receiving module 1102, configured to receive the uplink carrier identifier information and the dedicated RACH resource from the target base station, and output the uplink carrier identifier information and the dedicated RACH resource to a fourth sending module 1101.

It should be noted that the fourth sending module 1101 selects a target base station according to the downlink measurement result of the neighboring cell, and transmits the handover request message to the target base station after the target base station is selected.

Further, the fourth receiving module 1102 receives the uplink carrier id information and the dedicated RACH resource from the target base station through an X2, an eX2, or an Xn interface.

Further, the uplink carriers include SUL carriers and non-SUL carriers.

Further, the fourth sending module 1101 sends the received uplink carrier identification information and the dedicated RACH resource to the user equipment through a radio resource control message.

As shown in fig. 12, an embodiment of the present invention further provides a user equipment, which includes a fifth receiving module 1201 and a fifth sending module 1202, where:

a fifth receiving module 1201, configured to receive uplink carrier identification information and a dedicated RACH resource from an original base station to which a user equipment belongs, where the dedicated RACH resource includes a dedicated preamble, and send the uplink carrier identification information and the dedicated RACH resource to a fifth sending module 1202;

a fifth sending module 1202, configured to receive the uplink carrier identifier information and the dedicated RACH resource output by the fifth receiving module 1201, and send a dedicated preamble to the target base station on the uplink carrier indicated by the uplink carrier identifier information.

Further, the uplink carriers include SUL carriers and non-SUL carriers.

The present invention is further explained by providing several preferred embodiments, but it should be noted that the preferred embodiments are only for better describing the present invention and should not be construed as unduly limiting the present invention. The following embodiments may exist independently, and technical features in different embodiments may be combined and used in one embodiment.

For a random access process in a scene with a plurality of uplink carriers, according to a calculation scheme of RA-RNTI in an LTE system, and the MAC RAR message content only comprises TAC, UL Grant and Temporary C-RNTI, when different UEs in the same cell select different carriers at the same time domain position, the corresponding frequency domain positions are also the same, and the same Preamble code is sent, the UE cannot distinguish the MAC RAR, and random access failure can be caused. To solve this problem, adding Carrier Index to the MAC RAR message to distinguish different carriers may be considered.

For handover, in a scenario where a target cell has multiple uplink carriers, since the target base station only indicates a dedicated RACH resource, a carrier selected by the UE may not be consistent with a carrier selected by the target base station, which may cause a random access failure, that is, a handover failure. To solve this problem, it can be considered that the target base station needs to indicate Carrier in addition to the dedicated RACH resource.

The base station may configure multiple uplink carriers for the UE through Common Configuration in a system message or an RRC message, and each uplink carrier has its corresponding uplink Configuration, such as RACH Common Configuration (Common Configuration), PRACH Resource Configuration (Resource Configuration), and UL Power Control (Power Control) Common Configuration. If the base station configures 2 uplink carriers F1 and F2, one downlink carrier F3, wherein F2 and F3 are paired or unpaired carriers. The UE1 selects an uplink carrier F1 according to a configuration threshold or other scheme; the UE2 selects the uplink carrier F2 according to a configuration threshold or other scheme.

Here, the UE1 selects the same time domain location as the UE2 and selects the corresponding frequency domain resource location, and transmits the same Preamble code. After the base station receives Preamble codes of UE1 and UE2, if the calculation scheme of RA-RNTI in LTE system is adopted, then the calculation results of RA-RNTI of 2 UEs are the same, MAC RAR is generated, besides TAC, UL Grant and Temporary C-RNTI, a field such as Carrier Index is also needed to be included for distinguishing MAC RAR of different carriers, MAC RAR of two UEs are multiplexed together and sent to UE through the same downlink resource.

Wherein, the added field Carrier Index is used to indicate which Carrier MAC RAR, such as the uplink Carrier F1 used by the UE1, the Carrier Index of F1 may be added to the MAC RAR; the uplink Carrier F2 used by the UE2 is added with Carrier Index of F2 to the MAC RAR.

When the UE1 receives the Random Access Preamble Id (RAPID), it first parses the Random Access Preamble Id (RAPID), and since the RAPID of the UE1 and the RAPID of the UE2 are the same, it cannot be determined whether the MAC RAR belongs to the UE. Continuing to parse the MAC RAR, if the MAC RAR is found to include the carrier indication field and the carrier F1 is indicated, the UE1 considers the MAC RAR reception to be successful. The UE1 may send Msg3 on the indicated resource location; for the UE2, the rapid (preamble index) is analyzed the same, and likewise, the MAC RAR is continuously analyzed, and if the MAC RAR has a carrier indication field and the carrier indication field indicates the carrier F2, the MAC RAR is considered to be successfully received, and Msg3 is sent at the indicated resource location.

For a random access process with a plurality of uplink carriers, if a carrier is indicated in a MAC RAR message, after the UE receives the message, the UE can determine that the MAC RAR belongs to the UE according to the carrier in the MAC RAR and send Msg3 on the indicated carrier, under the condition that RAPID is the same, so that the random access success rate can be improved.

And for the switching process, the original base station selects the target base station according to the downlink measurement result of the adjacent cell. And after the target base station is selected, transmitting the switching request message to the target base station. If the target base station has a plurality of uplink carriers, the uplink transmission carrier needs to be selected after the handover request is received.

The uplink carrier selection scheme can be considered and selected according to the comparison between the downlink measurement result transmitted by the original base station and the threshold value, and can also be selected according to the access reliability of the carrier; in addition, an appropriate access carrier may be selected according to the uplink signal of the original base station measured by the target base station.

After the target base station selects the access carrier, the special RACH resource is selected on the access carrier, after the selection is well, the special RACH resource and the selected carrier are transmitted to the original base station, and the original base station configures the special RACH resource and the selected carrier to the UE through RRC information.

And after receiving the Preamble code, the UE sends the special Preamble code on the indicated carrier wave according to the configuration of the base station.

For the situation that a plurality of uplink carriers exist in the handover target cell, if the carrier for sending the dedicated preamble code is indicated, the handover success rate is also improved.

Preferred embodiment 1 (2 uplink carriers F1, F2, 1 downlink carrier F3, F2 and F3 are paired or unpaired carriers in a cell; 2 carriers are supported by UE; initial access and reestablishment)

The base station broadcasts 2 uplink carriers F1 and F2 through system messages, and one downlink carrier F3, F2 and F3 are paired or unpaired carriers. For the 2 uplink carriers F1 and F2, different uplink resources are broadcast, such as RACH Common Configuration (Common Configuration), PRACH Resource Configuration (Resource Configuration), and UL Power Control (Power Control) Common Configuration.

When an initial access or a random access procedure triggered due to a re-establishment is triggered, the following processing steps need to be performed:

step 1, UE selects an uplink carrier to access according to a carrier selection principle, and sends a Preamble code on the selected carrier;

step 2, after the base station receives the peable code, since there are 2 uplink carriers in the cell, when generating the MAC RAR message, Carrier Index needs to be introduced, for example, if the Carrier Index of F1 is 1, the Carrier Index of F2 is 0, and a bit needs to be added for indication, as shown in fig. 2. The Carrier Index field in fig. 2 is used to indicate the uplink Carrier Index (Carrier Index, CI), and the Padding field does not represent any useful information, but only Padding.

Step 3, the UE receives the MAC RAR message from the base station, and can parse the MAC RAR message according to the format shown in fig. 2, and if the parsed Carrier Index is consistent with the Carrier sending the Preamble code, the MAC RAR message sent to the UE is considered, that is, the MAC RAR is successfully received.

Preferred embodiment 2 (one cell has a plurality of uplink carriers F1, F2, F3, etc., some uplink carriers have corresponding downlink carriers, some have corresponding downlink carriers, UE supports all uplink carriers or more than 2 uplink carriers; initial access and reestablishment)

The base station broadcasts a plurality of uplink carriers through system messages, and broadcasts different uplink resources, such as RACH Common Configuration, PRACH Resource Configuration, UL Power Control Common Configuration, and the like, for each uplink carrier. When an initial access or a random access procedure triggered due to a re-establishment is triggered, the following processing steps need to be performed:

step 1, UE selects an access carrier according to a carrier selection principle on a supported uplink carrier, and sends a Preamble code on the selected access carrier;

and 2, after the base station receives the Preamble code, because the cell has a plurality of uplink carriers, a Carrier Index is required to be introduced when the MAC RAR message is generated. For example, if the current base station configures 4 uplink carriers, 2 bits may be added to indicate Carrier Index. As shown in fig. 3, a schematic structure diagram of a MAC RAR is given by taking the addition of a 2-bit field as an example. The Carrier Index field is used to indicate an uplink Carrier Index (Carrier Index, CI), and the Padding field does not represent any useful information and only performs Padding.

Step 3, the UE receives the MAC RAR message from the base station, and may perform parsing according to the MAC RAR format shown in fig. 3. And if the analyzed Carrier Index is consistent with the Carrier sending the Preamble code, the MAC RAR is considered to be successfully received.

Preferred embodiment 3 (2 uplink carriers F1, F2, 1 downlink carrier F3, F2 and F3 are paired or unpaired carriers in a cell; 2 carriers are supported by UE; random access process in connection state)

The base station is configured with 2 uplink carriers F1 and F2, and one downlink carrier F3, F2 and F3 are paired or unpaired carriers. The 2 uplink carriers F1 and F2 have respective Common configurations, such as RACH Common Configuration, PRACH Resource Configuration, and UL Power Control Common Configuration. When uplink desynchronization occurs and uplink or downlink data needs to be sent, a random access process is triggered; or, when the handover is performed, a contention random access procedure is triggered because there is no dedicated Preamble code.

For the triggered random access process, the following processing steps are carried out:

step 1, if the UE uses 2 uplink carriers for uplink transmission before random access, then before random access, it needs to select one uplink carrier for access according to the principle of carrier selection, and send a Preamble code on the selected carrier. If the UE uses only one carrier for uplink transmission before the random access trigger, the UE may select the carrier to send a Preamble code. Or for the switching process, the UE needs to select carriers according to the commonly configured carriers;

and 2, after the base station receives the Preamble code, because 2 uplink carriers exist in the cell, a Carrier Index needs to be introduced when the MAC RAR message is generated. For example, the MAC RAR format of fig. 2 may be used. After generating the MAC RAR message, the base station sends the MAC RAR message to the UE;

step 3, the UE receives the MAC RAR message from the base station, and may perform parsing according to the MAC RAR format in fig. 2. If the Carrier Index analyzed according to the format in fig. 2 is consistent with the Carrier sending the Preamble code, the MAC RAR is considered to be successfully received.

Preferred embodiment 4 (one cell has a plurality of uplink carriers F1, F2, F3, etc., some uplink carriers have corresponding downlink carriers, some have no corresponding downlink carriers; UE supports all uplink carriers or more than 2 uplink carriers)

The base station configures a plurality of uplink carriers, each having a different Common Configuration, such as RACH Common Configuration, PRACH Resource Configuration, and UL Power Control Common Configuration. When uplink desynchronization occurs and uplink or downlink data needs to be sent, a random access process is triggered. Or a random access procedure triggered by the absence of a dedicated Preamble code when handover is performed.

step 1, if the UE uses multiple uplink carriers for uplink transmission before random access, it needs to select an uplink carrier for access according to the principle of carrier selection and send a Preamble code on the selected carrier. If the UE uses only one carrier for uplink transmission before the random access trigger, the UE may select the carrier to send a Preamble code. Or for the handover procedure, the UE needs to perform carrier selection according to the commonly configured carriers.

And 2, after the base station receives the Preamble code, because the cell has a plurality of uplink carriers, a Carrier Index is required to be introduced when the MAC RAR message is generated. For example, there are 4 uplink carriers, the MAC RAR format in fig. 3 may be adopted. And after generating the MAC RAR message, the base station sends the MAC RAR message to the UE.

Step 3, the UE receives the MAC RAR message from the base station, and may perform parsing according to the MAC RAR format in fig. 3. And if the analyzed Carrier Index is consistent with the Carrier wave for sending the Preamble code, the MAC RAR is considered to be successfully received.

Preferred embodiment 5 (one cell has 2 uplink carriers SUL and non-SUL)

The base station configures 2 uplink carriers SUL and non-SUL, and 2 uplink carriers all have respective Common configurations, such as RACH Common Configuration, PRACH Resource Configuration, and UL Power Control Common Configuration. The UE supports the characteristics of the SUL and supports Band Combination (Band Combination) of the SUL and a Normal (Normal) carrier.

When an initial access or a random access procedure triggered due to a re-establishment is triggered, the following processing steps are performed:

step 1, the UE selects the carrier according to the carrier selection threshold and sends a Preamble code on the selected carrier.

And 2, after the base station receives the Preamble code, because the SUL Carrier and the non-SUL Carrier exist in the cell, when the MAC RAR message is generated, Carrier Index needs to be introduced, for example, 0 indicates the non-SUL Carrier, and 1 indicates the SUL Carrier. For example, the MAC RAR format of fig. 2 may be used. And after generating the MAC RAR message, the base station sends the MAC RAR message to the UE.

Step 3, the UE receives the MAC RAR message from the base station, and may perform parsing according to the MAC RAR format in fig. 2. If the Carrier Index parsed according to the format in fig. 2 coincides with the Carrier transmitting the Preamble code, the MAC RAR reception is considered successful.

Preferred embodiment 6 (multiple uplink carriers in a cell, e.g., multiple SULs and multiple non-SULs)

The base station configures a plurality of uplink carriers, for example, a plurality of SULs and a plurality of non-SULs, and the plurality of uplink carriers all have different Common configurations, for example, RACH Common Configuration, prachrhresource Configuration, UL Power Control Common Configuration, and the like. The UE supports the characteristics of the SUL and supports Band Combination of the SUL and Normal carriers. When an initial access or a random access procedure triggered due to a re-establishment is triggered, the following processing steps are performed:

Step 2, after the base station receives the Preamble code, because the cell has a plurality of uplink carriers, when generating the MAC RAR message, Carrier Index needs to be introduced, for example, a plurality of non-SULs are sequenced from 0, and finally, Carrier Index of SUL. In addition, a field indicating whether the Carrier Index exists is also required. For example, when there are 4 uplink carriers, the MAC RAR format shown in fig. 3 may be used. And after generating the MAC RAR message, the base station sends the MAC RAR message to the UE.

Step 3, the UE receives the MAC RAR message from the base station, and may perform parsing according to the MAC RAR format in fig. 3. If the Carrier Index parsed according to the format in fig. 3 is consistent with the Carrier transmitting the Preamble code, the MAC RAR reception is considered to be successful.

Preferred embodiment 7 (2 uplink carriers SUL and non-SUL exist in one cell; 2 carriers are supported by UE; random access procedure in connected state)

The base station configures 2 uplink carriers SUL and non-SUL, and 2 uplink carriers all have respective Common configurations, such as RACH Common Configuration, PRACH Resource Configuration, and UL Power Control Common Configuration. The UE supports the characteristics of the SUL and supports Band Combination of the SUL and Normal carriers. When uplink desynchronization occurs and uplink or downlink data needs to be sent, a random access process is triggered, or when switching is performed, the random access process is triggered due to the fact that no special Preamble code exists.

step 1, if the UE uses 2 uplink carriers for uplink transmission before random access, then before random access, it needs to select one uplink carrier for access according to the principle of carrier selection, and send a Preamble code on the selected carrier. If the UE uses only one carrier for uplink transmission before the random access trigger, the UE may select the carrier to send a Preamble code. For the handover process, the UE needs to select a carrier according to the commonly configured carrier, and send a Preamble code on the selected carrier.

Preferred embodiment 8 (multiple uplink carriers in a cell, e.g. 1 SUL and multiple non-SULs or SULs and non-SULs)

The base station configures a plurality of uplink carriers, for example, 1 SUL and a plurality of non-SULs, and the plurality of uplink carriers all have different Common configurations, for example, RACH Common Configuration, PRACH Resource Configuration, UL Power Control Common Configuration, and the like. The UE supports the characteristics of the SUL and supports Band Combination of the SUL and Normal carriers. When uplink desynchronization occurs and uplink or downlink data needs to be sent, a random access process is triggered. Or a random access procedure triggered by the absence of a dedicated Preamble code when handover is performed.

Step 2, after the base station receives the Preamble code, because the cell has a plurality of uplink carriers, when generating the MAC RAR message, Carrier Index needs to be introduced, for example, a plurality of non-SULs are sequenced from 0, and finally, Carrier Index of SUL. For example, when there are 4 uplink carriers, the MAC RAR format shown in fig. 3 may be used. And after generating the MAC RAR message, the base station sends the MAC RAR message to the UE.

Preferred embodiment 9 (target cell has 2 uplink carriers, handover process)

And the original base station selects a target base station according to the downlink measurement result and sends the switching request to the target base station. If the target base station has 2 uplink carriers, such as an SUL carrier and a non-SUL carrier, and according to the capability of the UE, the UE supports the SUL characteristic of the target base station and the Band Combination of the SUL and Normal carriers, the target base station selects a suitable carrier according to some principles, and selects a dedicated Preamble code and a dedicated PRACH resource on the carrier.

And the target base station transmits the selected carrier and the special RACH resource on the selected carrier to the original base station through an X2/eX2/Xn interface. And after receiving the carrier wave and the special RACH resource selected by the target base station, the original base station sends the carrier wave and the special RACH resource to the UE.

And after receiving the special Preamble code, the UE sends the special Preamble code to the target base station on the selected carrier.

After the target base station receives the Preamble code, because the cell has the SUL Carrier and the non-SUL Carrier, when generating the MAC RAR message, a Carrier Index needs to be introduced, for example, 0 indicates the non-SUL Carrier, and 1 indicates the SUL Carrier. For example, the MAC RAR format of fig. 2 may be used. And after the MAC RAR message is generated, the target base station sends the MAC RAR message to the UE.

The UE receives the MAC RAR message from the target base station, and may perform parsing according to the MAC RAR format in fig. 2. If the Carrier Index parsed according to fig. 2 is consistent with the Carrier transmitting the Preamble code, the MAC RAR reception is considered to be successful.

Preferred embodiment 10 (target cell has multiple uplink carriers)

And the original base station selects a target base station according to the downlink measurement result and sends the switching request to the target base station. If the target base station has a plurality of uplink carriers, such as a plurality of SUL carriers and a plurality of non-SUL carriers, and according to the capability of the UE, the UE supports the characteristics of a part of SUL and supports the Band Combination of the part of SUL and the Normal carrier; or the UE supports all SUL features and Band Combination of all SUL and Normal carriers. Then the base station selects a suitable carrier according to some principles from the supported carriers, and selects a dedicated Preamble code and a dedicated PRACH resource on the carrier.

After the target base station receives the Preamble code, because there are multiple uplink carriers in the cell, when generating the MAC RAR message, Carrier Index needs to be introduced, for example, multiple non-SULs are sequenced from 0, and finally, Carrier Index of SUL. In addition, a field indicating whether the Carrier Index exists is also required. For example, when there are 4 uplink carriers, the MAC RAR format shown in fig. 3 may be used. And after generating the MAC RAR message, the base station sends the MAC RAR message to the UE.

Step 3, the UE receives the MAC RAR message from the target base station, and may perform parsing according to the MAC RAR format in fig. 3. If the Carrier Index parsed according to the format in fig. 3 is consistent with the Carrier transmitting the Preamble code, the MAC RAR reception is considered to be successful.

In the present application, technical features in the respective embodiments may be combined and used in one embodiment without conflict. Each example is only a preferred embodiment of the present application, and is not intended to limit the scope of the present application.

It will be understood by those skilled in the art that all or part of the steps of the above methods may be implemented by instructing the relevant hardware through a program, and the program may be stored in a computer readable storage medium, such as a read-only memory, a magnetic or optical disk, and the like. Alternatively, all or part of the steps of the foregoing embodiments may also be implemented by using one or more integrated circuits, and accordingly, each module/unit in the foregoing embodiments may be implemented in the form of hardware, and may also be implemented in the form of a software functional module. The present invention is not limited to any specific form of combination of hardware and software.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for message transmission, comprising:

the method comprises the steps that user equipment receives a random access response message from a base station, wherein the random access response message comprises random access lead code identification information corresponding to the random access response message and uplink carrier identification information used for indicating the random access lead code corresponding to the random access response message, the random access response message also comprises a reserved field or a newly added field, and the reserved field or the newly added field is used for indicating whether a carrier indication domain exists or not;

2. The message transmission method according to claim 1, wherein the uplink carrier identification information is a carrier index number or a carrier name.

3. The message transmission method according to claim 2, wherein the uplink carriers include a secondary uplink carrier and a non-secondary uplink carrier.

4. The message transmission method according to claim 3, wherein the carrier index number of the non-assisted uplink carrier is smaller than the carrier index number of the assisted uplink carrier.

5. The message transmission method according to claim 1, wherein the selecting the uplink carrier by the ue comprises:

6. A method for message transmission, comprising:

and the base station sends a random access response message to the user equipment, wherein the random access response message comprises the random access preamble identification information and the uplink carrier identification information, the random access response message also comprises a reserved field or a newly added field, and the reserved field or the newly added field is used for indicating whether a carrier indication domain exists or not.

7. A computer-readable storage medium, characterized in that the computer-readable storage medium stores one or more programs which are executable by one or more processors to implement the steps of the message transmission method according to any one of claims 1 to 6.

8. The user equipment is characterized by comprising a first sending module, a first receiving module and a judging module, wherein:

a first receiving module, configured to receive a random access response message from a base station, where the random access response message includes random access preamble identification information corresponding to the random access response message and uplink carrier identification information used to indicate a random access preamble corresponding to the random access response message, and output the random access preamble identification information and the uplink carrier identification information to a determining module, where the random access response message further includes a reserved field or a newly added field, and the reserved field or the newly added field is used to indicate whether a carrier indication domain exists;

9. A base station, comprising a second receiving module and a second transmitting module, wherein:

a second sending module, configured to receive the random access preamble identification information and the uplink carrier identification information output by the second receiving module, and send a random access response message to the ue, where the random access response message includes the random access preamble identification information and the uplink carrier identification information, and the random access response message further includes a reserved field or a newly added field, and the reserved field or the newly added field is used to indicate whether a carrier indication domain exists.