CN116017779A

CN116017779A - Link reestablishment method and device, terminal and network equipment

Info

Publication number: CN116017779A
Application number: CN202111231700.8A
Authority: CN
Inventors: 黄学艳; 刘亮; 韩星宇
Original assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Current assignee: China Mobile Communications Group Co Ltd; China Mobile Communications Ltd Research Institute
Priority date: 2021-10-22
Filing date: 2021-10-22
Publication date: 2023-04-25

Abstract

The invention provides a link reestablishment method, a device, a terminal and network equipment, wherein the link reestablishment method comprises the following steps: under the condition that the PC5 link of the first terminal generates RLF, according to the RRC state of the Uu interface of the first terminal, adopting a first mode to send first information to network equipment; the first information includes: PC5 RLF information; receiving candidate second terminal information sent by network equipment; according to the candidate second terminal information, carrying out PC5 link reestablishment; wherein the employing a first mode includes any one of: through Uu interface; information through random access; by pre-configuring the resources. The scheme can avoid that the information can only be sent to the network equipment through the second terminal to reestablish the link, simplifies the implementation flow, shortens the time delay of link reestablishment, and well solves the problem of large time delay of the link reestablishment cube aiming at PC5 link failure in the prior art.

Description

Link reestablishment method and device, terminal and network equipment

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a method, an apparatus, a terminal, and a network device for link reestablishing.

Background

SL (bypass Relay) refers to a technology in which a mobile terminal establishes a PC5 (direct communication) connection with another terminal, and then uses the terminal as a Relay to access an access network. In SL Relay, a plurality of Remote UEs (terminals) may be connected to one Relay UE. And the plurality of bearers of the Remote UE are communicated with the access network through the Relay UE respectively. For Remote UEs, direct access RAN (radio access network) or access network through Relay UEs is selected by selection criteria based on PC5RSRP (reference signal received power), uu (air interface) RSRP, etc., i.e. Uu port (i.e. Uu interface) access or PC5 link (link) access.

Wherein, for the mode of accessing through the PC5 link, if the PC5 link fails in radio link (Radio link failure, RLF), the Remote UE triggers the Remote UE to reestablish connection (RRC connection re-establishments). That is, the current way to handle PC5 link failure is to initiate the reestablishment procedure by the Remote UE. Specifically, the basic procedure is that the terminal sends RRC (radio resource control) re-establishment request (re-establishment request) to the Relay UE, and then the Relay UE directly forwards RRC re-establishment request to the base station based on the current RRC state, or firstly establishes its RRC connection and then forwards RRC re-establishment request to the base station. The time delay of the whole process is very large.

From the above, the problem of large delay exists in the link reestablishment scheme aiming at the failure of the PC5 link in the prior art.

Disclosure of Invention

The invention aims to provide a link reestablishment method, a device, a terminal and network equipment, which are used for solving the problem of large time delay of a link reestablishment cube aiming at PC5 link failure in the prior art.

In order to solve the above technical problem, an embodiment of the present invention provides a link reestablishing method, which is applied to a first terminal and includes:

under the condition that a direct communication PC5 link of a first terminal generates Radio Link Failure (RLF), according to the Radio Resource Control (RRC) state of a Uu interface of the first terminal, adopting a first mode to send first information to network equipment; the first information includes: PC5 RLF information;

receiving candidate second terminal information sent by the network equipment;

according to the candidate second terminal information, carrying out PC5 link reestablishment;

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

Optionally, the first information further includes: at least one of PC5 measurement result information and PC5 measurement configuration information.

Optionally, the sending, by the first manner, the first information to the network device according to the radio resource control RRC state of the Uu interface of the first terminal includes:

in the case that the RRC state is an inactive state and the first terminal supports RRC inactive state transmission, sending, by means of random access information and/or by means of pre-configuring resources, first information to a network device;

wherein the random access information includes at least one of:

2, transmitting the message A in the SDT by the small data packet which is randomly accessed;

message 3 in SDT of 4 step random access.

under the condition that the RRC state is inactive and the first terminal does not support the transmission of the RRC inactive state, initiating an RRC recovery random access process;

and in the uplink scheduling after the RRC recovery random access process is completed or in the message 3 of the 4-step random access, sending first information to the network equipment through a Uu interface.

Under the condition that the RRC state is an idle state, initiating an air interface random access process;

under the condition that the air interface random access process is a 2-step random access process and the random access is successful, first information is sent to network equipment through a Uu interface;

and under the condition that the air interface random access process is a 4-step random access process, after the random access is successful or in a message 3 of the 4-step random access, sending first information to the network equipment through a Uu interface.

under the condition that the RRC state is in an idle state and the initiated air interface random access process fails, initiating a relay discovery process;

in the case that a second terminal meeting the first condition exists after the relay discovery process, sending first information to the network equipment through the second terminal;

wherein the first condition includes: the corresponding PC5 reference signal received power RSRP is greater than or equal to the PC5 RSRP threshold.

And under the condition that the RRC state is a connection state, sending first information to the network equipment through a Uu interface.

Optionally, the PC5 RLF information includes: type information of PC5 RLF;

wherein the type information includes at least one of:

PC5 connection reconfiguration failure;

the PC5 RLC reaches the maximum retransmission times;

the corresponding PC5 RSRP is below the PC5 RSRP threshold.

Optionally, the PC5 measurement result information includes at least one of:

the identification information of the first number of the second terminals, corresponding to the PC5 RSRP greater than or equal to the PC5 RSRP threshold;

a PC5 RSRP of the second terminal that is greater than or equal to the PC5 RSRP threshold;

ordering information of the second terminal greater than or equal to the configuration threshold.

Optionally, the PC5 measures configuration information including: PC5 RSRP threshold.

The embodiment of the invention also provides a link reestablishment method which is applied to the network equipment and comprises the following steps:

receiving first information sent by a first mode according to the Radio Resource Control (RRC) state of a Uu interface of a first terminal under the condition that the Radio Link Failure (RLF) occurs in a direct communication (PC 5) link; the first information includes: PC5 RLF information;

acquiring candidate second terminal information according to the first information;

Sending the candidate second terminal information to the first terminal;

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

Optionally, when the radio link failure RLF occurs in the direct communication PC5 link, the receiving first terminal uses the first information sent by the first mode according to the radio resource control RRC state of the Uu interface of the first terminal, where the first information includes:

receiving information of random access and/or first information sent by pre-configuring resources under the condition that a first terminal is in an inactive state and the first terminal supports RRC inactive state transmission;

wherein the random access information includes at least one of:

message 3 in SDT of 4 step random access.

And receiving first information sent by the first terminal through the Uu interface in uplink scheduling after completing the RRC recovery random access process or in a message 3 of 4-step random access under the condition that the first terminal is in an inactive state and the first terminal does not support RRC inactive state transmission.

receiving first information sent by a first terminal through a Uu interface under the condition that the RRC state is an idle state and the initiated 2-step random access process is successful; or,

and receiving first information sent by the first terminal through the Uu interface after the initiated 4-step random access process is successful or in the 4-step random access message 3 under the condition that the RRC state is an idle state.

Receiving first information sent by a second terminal meeting a first condition under the condition that the first terminal is in an idle state in the RRC state and the initiated air interface random access process fails;

and receiving the first information sent by the first terminal through the Uu interface under the condition that the RRC state is the connection state.

Optionally, the PC5 RLF information includes: type information of PC5 RLF;

wherein the type information includes at least one of:

PC5 connection reconfiguration failure;

the PC5 RLC reaches the maximum retransmission times;

the corresponding PC5 RSRP is below the PC5 RSRP threshold.

Optionally, the PC5 measurement result information includes at least one of:

The embodiment of the invention also provides a link reestablishment device which is applied to the first terminal and comprises the following components:

the first sending module is used for sending first information to the network equipment in a first mode according to the Radio Resource Control (RRC) state of a Uu interface of the first terminal under the condition that a direct communication (PC 5) link of the first terminal has Radio Link Failure (RLF); the first information includes: PC5 RLF information;

the first receiving module is used for receiving candidate second terminal information sent by the network equipment;

the first processing module is used for carrying out PC5 link reestablishment according to the candidate second terminal information;

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

wherein the random access information includes at least one of:

message 3 in SDT of 4 step random access.

Optionally, the PC5 RLF information includes: type information of PC5 RLF;

wherein the type information includes at least one of:

PC5 connection reconfiguration failure;

the PC5 RLC reaches the maximum retransmission times;

the corresponding PC5 RSRP is below the PC5 RSRP threshold.

Optionally, the PC5 measurement result information includes at least one of:

The embodiment of the invention also provides a link reestablishment device which is applied to the network equipment and comprises the following components:

the second receiving module is used for receiving first information sent by a first mode according to the Radio Resource Control (RRC) state of a Uu interface of the first terminal under the condition that the Radio Link Failure (RLF) occurs in a direct communication (PC 5) link; the first information includes: PC5 RLF information;

the first acquisition module is used for acquiring candidate second terminal information according to the first information;

The second sending module is used for sending the candidate second terminal information to the first terminal;

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

wherein the random access information includes at least one of:

message 3 in SDT of 4 step random access.

Optionally, the PC5 RLF information includes: type information of PC5 RLF;

wherein the type information includes at least one of:

PC5 connection reconfiguration failure;

the PC5 RLC reaches the maximum retransmission times;

the corresponding PC5 RSRP is below the PC5 RSRP threshold.

Optionally, the PC5 measurement result information includes at least one of:

The embodiment of the invention also provides a terminal, which is a first terminal and comprises: a processor and a transceiver;

the processor is configured to send, by using the transceiver, first information to a network device in a first manner according to a radio resource control RRC state of a Uu interface of a first terminal when a radio link failure RLF occurs in a direct communication PC5 link of the first terminal; the first information includes: PC5RLF information;

receiving candidate second terminal information sent by the network equipment through the transceiver;

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

wherein the random access information includes at least one of:

message 3 in SDT of 4 step random access.

Optionally, the PC5 RLF information includes: type information of PC5 RLF;

wherein the type information includes at least one of:

PC5 connection reconfiguration failure;

the PC5 RLC reaches the maximum retransmission times;

the corresponding PC5 RSRP is below the PC5 RSRP threshold.

Optionally, the PC5 measurement result information includes at least one of:

The embodiment of the invention also provides a network device, which comprises: a processor and a transceiver;

the processor is configured to receive, by using the transceiver, first information sent by a first mode according to a radio resource control RRC state of a Uu interface of the first terminal when a radio link failure RLF occurs in a direct communication PC5 link; the first information includes: PC5 RLF information;

transmitting the candidate second terminal information to the first terminal through the transceiver;

Wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

wherein the random access information includes at least one of:

message 3 in SDT of 4 step random access.

Optionally, the PC5 RLF information includes: type information of PC5 RLF;

wherein the type information includes at least one of:

PC5 connection reconfiguration failure;

the PC5 RLC reaches the maximum retransmission times;

the corresponding PC5 RSRP is below the PC5 RSRP threshold.

Optionally, the PC5 measurement result information includes at least one of:

The embodiment of the invention also provides a terminal which comprises a memory, a processor and a program which is stored in the memory and can run on the processor; and the processor realizes the link reestablishment method of the first terminal side when executing the program.

The embodiment of the invention also provides a network device which comprises a memory, a processor and a program which is stored in the memory and can run on the processor; and the processor realizes the link reestablishment method at the network equipment side when executing the program.

The embodiment of the invention also provides a readable storage medium, on which a program is stored, which when executed by a processor, implements the steps in the link reestablishment method of the first terminal side; or,

the program, when executed by the processor, implements the steps in the above-described method for link reestablishment on the network device side.

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

in the above scheme, in the link reestablishment method, when a radio link failure RLF occurs in a direct communication PC5 link of a first terminal, according to a radio resource control RRC state of a Uu interface of the first terminal, first information is sent to a network device in a first manner; the first information includes: PC5 RLF information; receiving candidate second terminal information sent by the network equipment; according to the candidate second terminal information, carrying out PC5 link reestablishment; wherein the employing a first mode includes any one of: through Uu interface; information through random access; by pre-configuring resources; the method can avoid that the information can only be sent to the network equipment through the second terminal to reconstruct the link, simplify the implementation flow, shorten the time delay of link reconstruction, and well solve the problem of large time delay of a link reconstruction cube aiming at PC5 link failure in the prior art.

Drawings

Fig. 1 is a schematic flow chart of a link reestablishment method according to an embodiment of the present invention;

fig. 2 is a flow chart diagram of a link reestablishment method according to an embodiment of the present invention;

fig. 3 is a schematic diagram of a link reestablishing device according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a link reestablishing device according to an embodiment of the present invention;

fig. 5 is a schematic diagram of a terminal structure according to an embodiment of the present invention;

fig. 6 is a schematic diagram of a network device according to an embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantages to be solved more apparent, the following detailed description will be given with reference to the accompanying drawings and specific embodiments.

The invention provides a link reestablishment method applied to a first terminal, which aims at the problem of large delay of a link reestablishment cube of PC5 link failure in the prior art, as shown in figure 1, and comprises the following steps:

step 11: under the condition that a direct communication PC5 link of a first terminal generates Radio Link Failure (RLF), according to the Radio Resource Control (RRC) state of a Uu interface of the first terminal, adopting a first mode to send first information to network equipment; the first information includes: PC5 RLF information;

step 12: receiving candidate second terminal information sent by the network equipment;

Step 13: according to the candidate second terminal information, carrying out PC5 link reestablishment; wherein the employing a first mode includes any one of: through Uu interface; information through random access; by pre-configuring the resources.

Wherein "candidate second terminal information" can be understood as: information of the candidate second terminal.

According to the link reestablishment method provided by the embodiment of the invention, under the condition that a Radio Link Failure (RLF) occurs in a direct communication (PC 5) link of a first terminal, first information is sent to network equipment in a first mode according to a Radio Resource Control (RRC) state of a Uu interface of the first terminal; the first information includes: PC5 RLF information; receiving candidate second terminal information sent by the network equipment; according to the candidate second terminal information, carrying out PC5 link reestablishment; wherein the employing a first mode includes any one of: through Uu interface; information through random access; by pre-configuring resources; the method can avoid that the information can only be sent to the network equipment through the second terminal to reconstruct the link, simplify the implementation flow, shorten the implementation time delay (namely the time delay of link reconstruction), and well solve the problem of large time delay of a link reconstruction cube for PC5 link failure in the prior art.

Wherein the first information further includes: at least one of PC5 measurement result information and PC5 measurement configuration information.

This can facilitate network device decision PC5 link reestablishment or PC5 measurement reconfiguration.

In the embodiment of the present invention, the sending, by a first manner, first information to a network device according to a radio resource control RRC state of a Uu interface of the first terminal includes: in the case that the RRC state is an inactive state and the first terminal supports RRC inactive state transmission, sending, by means of random access information and/or by means of pre-configuring resources, first information to a network device; wherein the random access information includes at least one of: 2, transmitting the message A in the SDT by the small data packet which is randomly accessed; message 3 in SDT of 4 step random access.

In this way, the Uu interface of the first terminal can be in an RRC inactive state, and the first terminal can send information to the network equipment for link reestablishment under the condition that the first terminal supports RRC inactive state transmission. Message a, i.e. MSGA, message 3, i.e. MSG3.

Wherein, the sending, by the first mode, the first information to the network device according to the radio resource control RRC state of the Uu interface of the first terminal includes: under the condition that the RRC state is inactive and the first terminal does not support the transmission of the RRC inactive state, initiating an RRC recovery random access process; and in the uplink scheduling after the RRC recovery random access process is completed or in the message 3 of the 4-step random access, sending first information to the network equipment through a Uu interface.

In this way, the Uu interface of the first terminal can be in an RRC inactive state, and the first terminal can send information to the network equipment for link reestablishment under the condition that the first terminal does not support RRC inactive state transmission.

In the embodiment of the present invention, the sending, by a first manner, first information to a network device according to a radio resource control RRC state of a Uu interface of the first terminal includes: under the condition that the RRC state is an idle state, initiating an air interface random access process; under the condition that the air interface random access process is a 2-step random access process and the random access is successful, first information is sent to network equipment through a Uu interface; and under the condition that the air interface random access process is a 4-step random access process, after the random access is successful or in a message 3 of the 4-step random access, sending first information to the network equipment through a Uu interface.

In this way, the Uu interface of the first terminal can send information to the network equipment to reestablish the link under the condition that the Uu interface is in an RRC idle state.

Wherein, the sending, by the first mode, the first information to the network device according to the radio resource control RRC state of the Uu interface of the first terminal includes: under the condition that the RRC state is in an idle state and the initiated air interface random access process fails, initiating a relay discovery process; in the case that a second terminal meeting the first condition exists after the relay discovery process, sending first information to the network equipment through the second terminal; wherein the first condition includes: the corresponding PC5 reference signal received power RSRP is greater than or equal to the PC5 RSRP threshold.

Therefore, the Uu interface of the first terminal can be ensured to be in an RRC idle state, and the relay discovery process is initiated under the condition that the first terminal fails to initiate the air interface random access process, so that the link re-establishment is completed.

In the embodiment of the present invention, the sending, by a first manner, first information to a network device according to a radio resource control RRC state of a Uu interface of the first terminal includes: and under the condition that the RRC state is a connection state, sending first information to the network equipment through a Uu interface.

In this way, the method can send information to the network equipment to reestablish the link under the condition that the Uu interface of the first terminal is in the RRC connection state.

Wherein the PC5 RLF information includes: type information of PC5 RLF; wherein the type information includes at least one of: PC5 connection reconfiguration failure; the PC5 RLC reaches the maximum retransmission times; the corresponding PC5 RSRP is below the PC5 RSRP threshold.

This can facilitate network device decision PC5 link reestablishment.

In an embodiment of the present invention, the PC5 measurement result information includes at least one of the following: the identification information of the first number of the second terminals, corresponding to the PC5 RSRP greater than or equal to the PC5 RSRP threshold; a PC5 RSRP of the second terminal that is greater than or equal to the PC5 RSRP threshold; ordering information of the second terminal greater than or equal to the configuration threshold.

This can facilitate the network device decision PC5 to measure reconfiguration.

Wherein the PC5 measures configuration information including: PC5 RSRP threshold.

This can facilitate the network device to accurately decide on PC5 link reestablishment or PC5 measurement reconfiguration.

The embodiment of the invention also provides a link reestablishment method, which is applied to the network equipment, as shown in fig. 2, and comprises the following steps:

step 21: receiving first information sent by a first mode according to the Radio Resource Control (RRC) state of a Uu interface of a first terminal under the condition that the Radio Link Failure (RLF) occurs in a direct communication (PC 5) link; the first information includes: PC5 RLF information;

step 22: acquiring candidate second terminal information according to the first information;

step 23: sending the candidate second terminal information to the first terminal; wherein the employing a first mode includes any one of: through Uu interface; information through random access; by pre-configuring the resources.

According to the link reestablishment method provided by the embodiment of the invention, under the condition that the radio link failure RLF occurs in the direct communication PC5 link, the first information sent by the first mode is adopted according to the radio resource control RRC state of the Uu interface of the first terminal; the first information includes: PC5 RLF information; acquiring candidate second terminal information according to the first information; sending the candidate second terminal information to the first terminal; wherein the employing a first mode includes any one of: through Uu interface; information through random access; by pre-configuring resources; the method can support and realize that information can be sent to network equipment only through the second terminal to reestablish the link, simplify the realization flow, shorten the realization time delay (namely the time delay of link reestablishment), and well solve the problem of large time delay of a link reestablishment cube aiming at PC5 link failure in the prior art.

In the embodiment of the present invention, when the receiving first terminal generates a radio link failure RLF in a direct communication PC5 link, according to a radio resource control RRC state of a Uu interface of the first terminal, first information sent by using a first mode includes: receiving information of random access and/or first information sent by pre-configuring resources under the condition that a first terminal is in an inactive state and the first terminal supports RRC inactive state transmission; wherein the random access information includes at least one of: 2, transmitting the message A in the SDT by the small data packet which is randomly accessed; message 3 in SDT of 4 step random access.

Therefore, the Uu interface of the first terminal can be supported to be in an RRC inactive state, and the link is re-established under the condition that the first terminal supports RRC inactive state transmission. Message a, i.e. MSGA, message 3, i.e. MSG3.

When the radio link failure RLF occurs in the direct communication PC5 link, the receiving first terminal uses the first information sent by the first mode according to the radio resource control RRC state of the Uu interface of the first terminal, where the first information includes: and receiving first information sent by the first terminal through the Uu interface in uplink scheduling after completing the RRC recovery random access process or in a message 3 of 4-step random access under the condition that the first terminal is in an inactive state and the first terminal does not support RRC inactive state transmission.

Therefore, the Uu interface of the first terminal can be supported to be in an RRC inactive state, and the link is re-established under the condition that the first terminal does not support RRC inactive state transmission.

In the embodiment of the present invention, when the receiving first terminal generates a radio link failure RLF in a direct communication PC5 link, according to a radio resource control RRC state of a Uu interface of the first terminal, first information sent by using a first mode includes: receiving first information sent by a first terminal through a Uu interface under the condition that the RRC state is an idle state and the initiated 2-step random access process is successful; or receiving the first information sent by the first terminal through the Uu interface after the initiated 4-step random access process is successful or in the message 3 of the 4-step random access under the condition that the RRC state is the idle state.

In this way, the link reestablishment can be supported under the condition that the Uu interface of the first terminal is in an RRC idle state.

When the radio link failure RLF occurs in the direct communication PC5 link, the receiving first terminal uses the first information sent by the first mode according to the radio resource control RRC state of the Uu interface of the first terminal, where the first information includes: receiving first information sent by a second terminal meeting a first condition under the condition that the first terminal is in an idle state in the RRC state and the initiated air interface random access process fails; wherein the first condition includes: the corresponding PC5 reference signal received power RSRP is greater than or equal to the PC5 RSRP threshold.

In the embodiment of the present invention, when the receiving first terminal generates a radio link failure RLF in a direct communication PC5 link, according to a radio resource control RRC state of a Uu interface of the first terminal, first information sent by using a first mode includes: and receiving the first information sent by the first terminal through the Uu interface under the condition that the RRC state is the connection state.

In this way, the link reestablishment can be supported under the condition that the Uu interface of the first terminal is in the RRC connection state.

This can facilitate network device decision PC5 link reestablishment.

This can facilitate the network device decision PC5 to measure reconfiguration.

Here, the first terminal in the embodiment of the present invention may be implemented as a remote terminal, which may also be referred to as a remote terminal, and the second terminal may be implemented as a relay terminal, but is not limited thereto.

The link reestablishing method provided by the embodiment of the invention is illustrated below, and the first terminal takes a remote terminal as an example, and the remote terminal is called as a terminal for short; the second terminal is exemplified by a relay terminal.

Aiming at the technical problems, considering that Remote UE (terminal) can support Uu connection and PC5 dual connection, the embodiment of the invention provides a link reestablishment method, which can be specifically realized as a link reestablishment method for recovering PC5 connection in different states of Uu port (corresponding to the Uu interface) after PC5 link failure aiming at the terminal in the dual connection of PC5 and Uu port; mainly relates to the following four parts:

part 1. For a terminal supporting both a PC5 connection and an air interface connection (i.e., uu interface connection), i.e., supporting both a PC5 and Uu interface dual connection, if the PC5 link fails, embodiments of the present invention provide examples of three cases to address;

Case (Case) 1: the air interface connection is at RRC inactive (inactive), i.e. radio bearers (radio bearers) of Uu are disabled (suspended); corresponding to the RRC state being inactive;

(1) If the terminal supports RRC inactive state data transmission: 1) If the terminal initiates 2 steps of RA (random access) -SDT (small packet data transmission), the terminal can report PC5RLF to the network (corresponding to the network equipment) in the PUSCH (uplink shared channel) of the MSGA (message A); if the PC5 measurement result information exists, the PC5 measurement result information can be reported; if the PC5 measurement configuration information exists, the PC5 measurement configuration information can be reported to the network; 2) If the terminal initiates 4 steps RA-SDT, the terminal reports PC5RLF to the network in MSG3 (message 3); if the PC5 measurement result information exists, the PC5 measurement result information can be reported; if the PC5 measurement configuration information exists, the PC5 measurement configuration information can be reported to the network; 3) If the terminal initiates CG (pre-configuration) -SDT, the terminal reports PC5RLF to the network on CG resource; if the PC5 measurement result information exists, the PC5 measurement result information can be reported; if the PC5 measurement configuration information exists, the PC5 measurement configuration information can be reported to the network;

(2) If the terminal does not support RRC inactive state data transmission, the terminal may initiate an RRC resume random access procedure. In the uplink scheduling after finishing RRC resume random access or in msg3 of 4 steps of RA-SDT, the terminal reports PC5RLF to the network through Uu port; if the PC5 measurement result information exists, the PC5 measurement result information can be reported; if the PC5 measurement configuration information exists, the PC5 measurement configuration information can be reported to the network;

Case2: the air interface connection is in RRC idle (idle state);

in the invention, the PC5 link is a radio link failure condition, which can be understood that the PC5 link is unstable currently. Therefore, it can be considered to restrict the terminal to resume the RRC connection with the base station by discovering (discovery) Relay before initiating random access through Relay.

(1) The terminal initiates an air interface random access process.

If the terminal initiates a 2-step random access process, the terminal reports PC5 RLF to the network through a Uu port after the random access is successful; if the PC5 measurement result information exists, the PC5 measurement result information can be reported; if the PC5 measurement configuration information exists, the PC5 measurement configuration information can be reported to the network; 2) If the terminal initiates a 4-step random access process, after the random access is successful or in msg3, the terminal reports PC5 RLF to the network through a Uu port; if the PC5 measurement result information exists, the PC5 measurement result information can be reported; if the PC5 measurement configuration information exists, the PC5 measurement configuration information can be reported to the network;

(2) If the terminal fails to initiate the air interface random access process, the terminal can initiate a Relay discovery process, namely, the PC5 RSRP is compared with a PC5 RSRP threshold, and if the PC5 RSRP of the Relay UE is greater than or equal to the PC5 RSRP threshold, a PC5 connection establishment flow can be initiated. And sending the first information to the network equipment through the second terminal under the condition that the second terminal meeting the first condition exists after the relay discovery process.

Case3: the air interface connection is at RRC connection (i.e., RRC connected), i.e., uu interface radio bearers (radio bearers) are not barred;

the terminal can report the PC5 RLF to the network through the Uu port; if the PC5 measurement result information exists, the PC5 measurement result information can be reported; if there is PC5 measurement configuration information, the PC5 measurement configuration information may be reported to the network.

Section 2. Reporting the PC5 RLF mentioned in section 1, wherein type information of the reporting PC5 RLF may be included, the type information may comprise at least one of the following: PC5 connection reconfiguration failed, PC5 RLC reached maximum number of retransmissions, PC5 RSRP (corresponding) was below the (PC 5 RSRP) threshold;

part 3. The PC5 measurement result information mentioned in part 1 contains at least: identification information of 0 or one or more Relay terminals higher than or equal to the PC5-RSRP threshold; additionally, one or more of the following information may be included: a PC5-RSRP of the Relay terminal that is greater than or equal to the configuration threshold (i.e., the PC5-RSRP threshold); the strength ordering (namely the ordering information) of the Relay terminals which are higher than or equal to the configuration threshold;

section 4. The PC5 measurement configuration information mentioned in section 1 may include a PC5-RSRP threshold.

Wherein the information involved in parts 3 and 4 can be used for network device decision PC5 link re-establishment or PC5 measurement reconfiguration. The specific examples are:

(1) The network judges the possible reasons of the current PC5 RLF based on the type information of the PC5 RLF described in the part 2: 1) The PC5 RSRP is lower than the corresponding threshold value, so that the positions of the Relay UE and the Remote UE can be judged to be far, and the transmission reliability of the current PC5 link is poor; 2) The maximum retransmission times reached by the PC5 RLC can be judged as poor transmission reliability of the PC5 links of the Relay UE and the Remote UE, or the Relay UE is overloaded and cannot be scheduled, and the service of the Remote UE is put aside; 3) The PC5 connection reconfiguration failure can be judged that the above-described several possibilities exist. These decision information can be used as a reference for the network to select a new Relay UE.

(2) The network selects a Relay UE based on the identification information of the Relay terminal described in the section 3 in combination with the type information of the PC5 RLF described in the section 2, and feeds back the information of the Relay UE to the terminal. The terminal performs PC5 connection re-establishment based on candidate Relay UE information (corresponding to the above candidate second terminal information) fed back by the network. If the number of candidate Relay UEs fed back is 0, the network considers that there is no suitable Relay UE.

(3) The network judges whether the current PC5 RSRP threshold is reasonable or not based on the PC5 measurement configuration information described in the part 4 and the identification information of the Relay terminal described in the part 3, and reconfigures the PC5 RSRP threshold of the terminal based on the information.

As can be seen from the above, the embodiment of the present invention provides a link reestablishing method, which can implement a scheme for recovering a PC5 link by a Relay terminal in different RRC inactive, idle and connected states; supporting to send PC5 measurement results, PC5 configuration information and the like in an RRC inactive state; the efficiency of PC5 link re-establishment can be improved.

The embodiment of the invention also provides a link reestablishment device, which is applied to the first terminal, as shown in fig. 3, and comprises:

a first sending module 31, configured to send, in a first manner, first information to a network device according to a radio resource control RRC state of a Uu interface of a first terminal when a radio link failure RLF occurs in a direct communication PC5 link of the first terminal; the first information includes: PC5 RLF information;

a first receiving module 32, configured to receive candidate second terminal information sent by the network device;

a first processing module 33, configured to perform PC5 link reestablishment according to the candidate second terminal information;

Wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

According to the link reestablishment device provided by the embodiment of the invention, under the condition that Radio Link Failure (RLF) occurs in a direct communication (PC 5) link of a first terminal, first information is sent to network equipment in a first mode according to the Radio Resource Control (RRC) state of a Uu interface of the first terminal; the first information includes: PC5 RLF information; receiving candidate second terminal information sent by the network equipment; according to the candidate second terminal information, carrying out PC5 link reestablishment; wherein the employing a first mode includes any one of: through Uu interface; information through random access; by pre-configuring resources; the method can avoid that the information can only be sent to the network equipment through the second terminal to reconstruct the link, simplify the implementation flow, shorten the time delay of link reconstruction, and well solve the problem of large time delay of a link reconstruction cube aiming at PC5 link failure in the prior art.

In the embodiment of the present invention, the PC5 measures configuration information including: PC5 RSRP threshold.

The embodiments of the link reestablishment method at the first terminal side are applicable to the embodiments of the link reestablishment device, and the same technical effects can be achieved.

The embodiment of the invention also provides a link reestablishment device, which is applied to network equipment, as shown in fig. 4, and comprises:

a second receiving module 41, configured to receive, when a radio link failure RLF occurs in a direct communication PC5 link, first information sent by a first mode according to a radio resource control RRC state of a Uu interface of the first terminal; the first information includes: PC5 RLF information;

a first obtaining module 42, configured to obtain candidate second terminal information according to the first information;

a second sending module 43, configured to send the candidate second terminal information to the first terminal;

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

The link reestablishing device provided by the embodiment of the invention adopts the first information sent by the first mode according to the Radio Resource Control (RRC) state of the Uu interface of the first terminal under the condition that the Radio Link Failure (RLF) occurs in the direct communication (PC 5) link by receiving the first information; the first information includes: PC5 RLF information; acquiring candidate second terminal information according to the first information; sending the candidate second terminal information to the first terminal; wherein the employing a first mode includes any one of: through Uu interface; information through random access; by pre-configuring resources; the method can support and realize that information can be sent to network equipment only through the second terminal to reestablish the link, simplify the realization flow, shorten the time delay of link reestablishment, and well solve the problem of large time delay of a link reestablishment cube aiming at PC5 link failure in the prior art.

The embodiments of the method for reestablishing the link on the network device side are applicable to the embodiments of the device for reestablishing the link, and the same technical effects can be achieved.

The embodiment of the invention also provides a terminal, which is a first terminal, as shown in fig. 5, and includes: a processor 51 and a transceiver 52;

the processor 51 is configured to send, through the transceiver 52, first information to a network device in a first manner according to a radio resource control RRC state of a Uu interface of a first terminal when a radio link failure RLF occurs in a direct communication PC5 link of the first terminal; the first information includes: PC5RLF information;

receiving candidate second terminal information transmitted by the network device through the transceiver 52;

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

In the case that the radio link failure RLF occurs in the direct communication PC5 link of the first terminal, the terminal provided in the embodiment of the present invention sends the first information to the network device in the first manner according to the radio resource control RRC state of the Uu interface of the first terminal; the first information includes: PC5RLF information; receiving candidate second terminal information sent by the network equipment; according to the candidate second terminal information, carrying out PC5 link reestablishment; wherein the employing a first mode includes any one of: through Uu interface; information through random access; by pre-configuring resources; the method can avoid that the information can only be sent to the network equipment through the second terminal to reconstruct the link, simplify the implementation flow, shorten the time delay of link reconstruction, and well solve the problem of large time delay of a link reconstruction cube aiming at PC5 link failure in the prior art.

The embodiments of the link reestablishment method at the first terminal side are applicable to the embodiments of the terminal, and the same technical effects can be achieved.

The embodiment of the invention also provides a network device, as shown in fig. 6, including: a processor 61 and a transceiver 62;

The processor 61 is configured to receive, through the transceiver 62, first information sent by a first mode according to a radio resource control RRC state of a Uu interface of a first terminal when a radio link failure RLF occurs in a direct communication PC5 link; the first information includes: PC5 RLF information;

transmitting the candidate second terminal information to the first terminal through the transceiver 62;

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

The network device provided by the embodiment of the invention adopts the first information sent by the first mode according to the Radio Resource Control (RRC) state of the Uu interface of the first terminal under the condition that the Radio Link Failure (RLF) occurs in the direct communication (PC 5) link by receiving the first information; the first information includes: PC5 RLF information; acquiring candidate second terminal information according to the first information; sending the candidate second terminal information to the first terminal; wherein the employing a first mode includes any one of: through Uu interface; information through random access; by pre-configuring resources; the method can support and realize that information can be sent to network equipment only through the second terminal to reestablish the link, simplify the realization flow, shorten the time delay of link reestablishment, and well solve the problem of large time delay of a link reestablishment cube aiming at PC5 link failure in the prior art.

The implementation embodiments of the link reestablishment method at the network device side are applicable to the embodiments of the network device, and the same technical effects can be achieved.

The embodiments of the link reestablishment method at the first terminal side or the network device side are applicable to the embodiment of the readable storage medium, and the same technical effects can be achieved.

It should be noted that many of the functional components described in this specification have been referred to as modules, in order to more particularly emphasize their implementation independence.

In an embodiment of the invention, the modules may be implemented in software for execution by various types of processors. An identified module of executable code may, for instance, comprise one or more physical or logical blocks of computer instructions which may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified module need not be physically located together, but may comprise disparate instructions stored in different bits which, when joined logically together, comprise the module and achieve the stated purpose for the module.

Indeed, a module of executable code may be a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. Likewise, operational data may be identified within modules and may be embodied in any suitable form and organized within any suitable type of data structure. The operational data may be collected as a single data set, or may be distributed over different locations including over different storage devices.

Where a module may be implemented in software, taking into account the level of existing hardware technology, a module may be implemented in software, and one skilled in the art may, without regard to cost, build corresponding hardware circuitry, including conventional Very Large Scale Integration (VLSI) circuits or gate arrays, and existing semiconductors such as logic chips, transistors, or other discrete components, to achieve the corresponding functions. A module may also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices or the like.

While the foregoing is directed to the preferred embodiments of the present invention, it will be appreciated by those skilled in the art that various modifications and changes can be made without departing from the principles of the present invention, and such modifications and changes should also be considered as being within the scope of the present invention.

Claims

1. The link reestablishment method is applied to a first terminal and is characterized by comprising the following steps:

Receiving candidate second terminal information sent by the network equipment;

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

2. The link reestablishment method according to claim 1, wherein said first information further comprises: at least one of PC5 measurement result information and PC5 measurement configuration information.

3. The link reestablishment method according to claim 1, wherein said sending the first information to the network device in the first manner according to the radio resource control RRC state of the Uu interface of the first terminal includes:

wherein the random access information includes at least one of:

message 3 in SDT of 4 step random access.

4. A link reestablishment method according to claim 1 or 3, wherein said sending, according to the radio resource control RRC state of the Uu interface of said first terminal, first information to the network equipment in a first manner comprises:

5. The link reestablishment method according to claim 1, wherein said sending the first information to the network device in the first manner according to the radio resource control RRC state of the Uu interface of the first terminal includes:

6. The method for re-establishing a link according to claim 5, wherein the sending the first information to the network device in the first manner according to the radio resource control RRC state of the Uu interface of the first terminal includes:

7. The link reestablishment method according to claim 1, wherein said sending the first information to the network device in the first manner according to the radio resource control RRC state of the Uu interface of the first terminal includes:

8. The link reestablishment method according to claim 1, wherein said PC5 RLF information includes: type information of PC5 RLF;

wherein the type information includes at least one of:

PC5 connection reconfiguration failure;

the PC5 RLC reaches the maximum retransmission times;

the corresponding PC5 RSRP is below the PC5 RSRP threshold.

9. The link reestablishment method according to claim 2, wherein said PC5 measurement result information includes at least one of:

10. The link reestablishment method according to claim 2, wherein said PC5 measures configuration information comprising: PC5 RSRP threshold.

11. A link reestablishment method applied to a network device, comprising:

sending the candidate second terminal information to the first terminal;

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

12. The link reestablishment method according to claim 11, wherein said first information further comprises: at least one of PC5 measurement result information and PC5 measurement configuration information.

13. The link reestablishment method according to claim 11, wherein said receiving the first information sent by the first terminal in the first manner according to the radio resource control RRC state of the Uu interface of the first terminal in the case that the radio link failure RLF occurs in the direct communication PC5 link includes:

wherein the random access information includes at least one of:

message 3 in SDT of 4 step random access.

14. The link reestablishment method according to claim 11 or 13, wherein said receiving the first information sent by the first terminal in the first manner according to the radio resource control RRC state of the Uu interface of the first terminal in the case that the direct communication PC5 link has a radio link failure RLF, comprises:

15. The link reestablishment method according to claim 11, wherein said receiving the first information sent by the first terminal in the first manner according to the radio resource control RRC state of the Uu interface of the first terminal in the case that the radio link failure RLF occurs in the direct communication PC5 link includes:

16. The method for re-establishing a link according to claim 15, wherein the receiving the first information sent by the first terminal in the first manner according to the radio resource control RRC state of the Uu interface of the first terminal in the case where the radio link failure RLF occurs in the direct communication PC5 link includes:

17. The link reestablishment method according to claim 11, wherein said receiving the first information sent by the first terminal in the first manner according to the radio resource control RRC state of the Uu interface of the first terminal in the case that the radio link failure RLF occurs in the direct communication PC5 link includes:

18. The link reestablishment method according to claim 11, wherein said PC5 RLF information includes: type information of PC5 RLF;

wherein the type information includes at least one of:

PC5 connection reconfiguration failure;

the PC5 RLC reaches the maximum retransmission times;

the corresponding PC5 RSRP is below the PC5 RSRP threshold.

19. The link reestablishment method according to claim 12, wherein said PC5 measurement result information includes at least one of:

20. The link reestablishment method according to claim 12, wherein said PC5 measures configuration information comprising: PC5 RSRP threshold.

21. A link reestablishment device applied to a first terminal, comprising:

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

22. A link reestablishment device applied to a network device, comprising:

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

23. A terminal, the terminal being a first terminal, comprising: a processor and a transceiver;

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

24. A network device, comprising: a processor and a transceiver;

wherein the employing a first mode includes any one of:

through Uu interface;

information through random access;

by pre-configuring the resources.

25. A terminal comprising a memory, a processor and a program stored on the memory and executable on the processor; the link reestablishment method according to any one of claims 1-10, characterized in that said processor, when executing said program, implements said link reestablishment method.

26. A network device comprising a memory, a processor, and a program stored on the memory and executable on the processor; the link reestablishment method according to any one of claims 11-20, characterized in that said processor, when executing said program, implements said link reestablishment method.

27. A readable storage medium having stored thereon a program, which when executed by a processor, implements the steps of the link reestablishment method according to any one of claims 1-10; or,

the program, when executed by a processor, implements the steps of the link re-establishment method as claimed in any of the claims 11 to 20.