Method performed by a user equipment and user equipment

Abstract

The application provides a method executed by a user equipment and the user equipment. The method executed by the user equipment comprises: a radio access AS layer of the user equipment UE determining a sidelink DRX parameter, the radio access AS layer notifying first configuration information to a V2X layer of the UE, and the V2X layer prolonging a time length of a PC5 unicast link keep-alive timer according to the first configuration information.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wireless communication, and more particularly, the present application relates to a method for performing sidelink DRX by a user equipment and a corresponding user equipment. BACKGROUND

[0002] In June 2018, the V2X feasibility study item based on 5G NR network technology in Release 16 (see Non-Patent Literature: RP-181480, New SID Proposal: Study on NR V2X) was approved at the 3rd Generation Partnership Project (3GPP) RAN#80 plenary. The main functions of Release 16 NR V2X include supporting unicast, groupcast and broadcast in network coverage and non-network coverage scenarios.

[0003] In December 2019, the Rel-17 enhanced sidelink communication (NR sidelink enhancement) item based on 5G NR network technology (see Non-Patent Literature: RP-193257 New WID on NR sidelink enhancement) was approved at the 3GPP RAN#86 plenary. The latest version of this item is described in Non-Patent Literature: RP-202846 WID NR Sidelink Enhancement.

[0004] The research objectives of enhanced NR sidelink communication mainly include two aspects: reducing the power consumption of user equipment (power saving), enhancing the reliability of sidelink communication, and reducing the communication delay. In order to support power saving of user equipment, the specific research objectives include supporting sidelink DRX for broadcast, groupcast and unicast.

[0005] The present application discusses related issues of sidelink DRX in unicast scenarios. SUMMARY

[0006] The purpose of the present application is to provide a method for extending the length of a PC5 unicast link keep-alive timer when a user equipment performs sidelink DRX and a corresponding user equipment.

[0007] According to an aspect of the present application, a method performed by a user equipment is provided, including determining sidelink DRX parameters by a radio access AS layer of the user equipment (UE), notifying first configuration information to a V2X layer of the UE by the radio access AS layer, and extending the length of a PC5 unicast link keep-alive timer by the V2X layer according to the first configuration information.

[0008] In the method performed by the user equipment, the method in which the radio access AS layer determines the sidelink DRX parameter includes at least one of the following methods: determination according to a sidelink DRX configuration in a system message or RRC dedicated signaling received from a base station; determination according to a service type or QoS feature indicated by a V2X layer; determination according to a sidelink DRX configuration in a PC5 RRC message or MAC CE received from a peer UE; determination according to a sidelink DRX configuration negotiated with the peer UE; and determination according to a protocol specified value.

[0009] In the method performed by the user equipment, the first configuration information includes at least one of the following information: the first configuration information is part of the sidelink DRX parameter; the first configuration information is all of the sidelink DRX parameter; the first configuration information is a DRX cycle set to 0 or an invalid value determined according to the sidelink DRX parameter configuration; the first configuration information is an indication that the sidelink DRX parameter is configured; the first configuration information is an indication to extend a link keep-alive timer; the first configuration information is a length of the link keep-alive timer after extension; and the first configuration information is a length of the link keep-alive timer after extension.

[0010] In the method performed by the user equipment, after the V2X layer receives the first configuration information, the method in which the PC5 unicast link keep-alive timer is extended includes at least one of the following methods: the length of the T5003 / T5004 timer is extended by the DRX cycle indicated by the first configuration information; the length of the T5003 / T5004 timer is extended by the product of the DRX cycle indicated by the first configuration information and a coefficient; the length of the T5003 / T5004 timer is extended by the length of the link keep-alive timer extended by the first configuration information; the length of the T5003 / T5004 timer is extended by the product of the length of the link keep-alive timer extended by the first configuration information and a coefficient; the length of the T5003 / T5004 timer is set to the length of the link keep-alive timer after extension indicated by the first configuration information; and the length of the T5003 / T5004 timer is extended by a fixed length.

[0011] According to another aspect of the present application, a method performed by a user equipment includes the following steps: a radio access AS layer of the user equipment UE determines to stop sidelink DRX, the radio access AS layer informs a V2X layer of the UE of first stop information, and the V2X layer stops extending a length of a PC5 unicast link keep-alive timer according to the first stop information.

[0012] In the method performed by the user equipment, the method for determining to stop sidelink DRX by the AS layer includes at least one of the following: releasing the sidelink DRX configuration according to the release sidelink DRX configuration indicated in the system message or RRC dedicated signaling received from the base station; releasing the sidelink DRX configuration according to the traffic type or QoS characteristics indicated by the V2X layer; releasing the sidelink DRX configuration according to the release sidelink DRX configuration indicated in the PC5 RRC message or MAC CE received from the peer UE; and releasing the sidelink DRX configuration according to the result of negotiation with the peer UE.

[0013] In the method performed by the user equipment, the first stop information includes at least one of the following: the first stop information is an indication to stop sidelink DRX; the first stop information is a sidelink DRX cycle set to 0 or an invalid value; the first stop information is an indication to stop extending the link keep-alive timer; the first stop information is a link keep-alive timer duration set to 0 or an invalid value; and the first stop information is a link keep-alive timer extension duration set to 0 or an invalid value.

[0014] In the method performed by the user equipment, after the V2X layer receives the stop sidelink DRX information, the method for stopping extending the PC5 unicast link keep-alive timer duration includes at least one of the following: no longer extending the duration of the T5003 / T5004 timer; and returning the value of T5003 / T5004 to the original T5003 / T5004 value.

[0015] According to another aspect of the present application, a user equipment is also provided, comprising: a processor; and a memory storing instructions; wherein the instructions, when executed by the processor, perform the method provided in each of the above aspects.

[0016] According to the method provided by the present application, in the enhanced sidelink communication, when the sidelink DRX is introduced, it can be ensured that the sidelink user equipment can reasonably set the PC5 unicast link keep-alive process related timer duration, reduce unnecessary signaling interaction, and prevent abnormal release of the PC5 unicast link, so as to not only reduce power consumption but also improve the reliability of the sidelink communication. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a schematic diagram for explaining the PC5 unicast link keep-alive process.

[0018] Figure 2 is a flowchart of the method for extending the keep-alive timer according to embodiment 1 of the present application.

[0019] Figure 3 is a flowchart of the method for stopping extending the keep-alive timer according to embodiment 2 of the present application.

[0020] Figure 4 is a brief structure block diagram of a user equipment UE to which the present application relates. DETAILED DESCRIPTION

[0021] The present application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the present application should not be limited to the specific embodiments described below. In addition, for the sake of simplicity, detailed descriptions of well-known technology that is not directly related to the present application are omitted to prevent confusion in understanding the present application.

[0022] Some terms related to the present application are described below, and the specific meanings of the terms can be found in the latest 3GPP standard specifications such as TS 38.300, TS 38.331, TS 36.300, TS 36.331, etc. Unless otherwise indicated, the terms related to the present application have the meanings below.

[0023] UE: User Equipment

[0024] NR: New Radio

[0025] RRC: Radio Resource Control

[0026] RRC_CONNECTED: RRC connected state

[0027] RRC_INACTIVE: RRC inactive state

[0028] RRC_IDLE: RRC idle state

[0029] RAN: Radio Access Network

[0030] Sidelink: Sidelink communication

[0031] SDAP: Service Data Adaptation Protocol

[0032] SCI: Sidelink Control Information

[0033] RSRP: Reference Signal Receiving Power

[0034] PSCCH: Physical Sidelink Control Channel

[0035] PSSCH: Physical Sidelink Shared Channel

[0036] AS: Access Stratum

[0037] DL: Downlink

[0038] IE: Information Element

[0039] CE: Control Element

[0040] MIB: Master Information Block

[0041] NR: New Radio

[0042] SIB: System Information Block

[0043] NG-RAN: NG Radio Access Network, a next-generation radio access network

[0044] 5GC: 5G Core Network

[0045] PDU: Protocol Data Unit

[0046] SDU: Service Data Unit

[0047] DRX: Discontinuous Reception

[0048] V2X: Vehicle-to-Everything.

[0049] MAC: Medium Access Control

[0050] QoS: Quality of Service

[0051] In this invention, the network, base station, and RAN can be used interchangeably. The network can be a Long Term Evolution (LTE) network, a New Radio Access Technology (New RAT, NR) network, an enhanced Long Term Evolution (eLTE) network, or other networks defined in subsequent 3GPP evolution versions.

[0052] In the present application, the user equipment UE can refer to the NR device supporting the NR Sidelink function as described in the background art, or can refer to other types of NR devices or LTE devices.

[0053] The PC5 interface is an interface for the control plane and user plane Sidelink communication between UEs. For Sidelink unicast, the PC5-RRC connection is an AS layer logical connection between a pair of source Layer-2 ID and target Layer-2 ID. One PC5 unicast link establishment corresponds to one PC5-RRC connection establishment.

[0054] After adopting the Sidelink DRX, the UE does not continuously monitor or receive the downlink channel, but periodically wakes up to receive or monitor the Sidelink channel for a period of time, which can be referred to as the Sidelink DRX cycle or Sidelink DRX cycle.

[0055] In the Sidelink unicast scenario, the PC5 unicast link keep-alive procedure of the V2X layer is used to maintain the PC5 unicast link between two UEs, i.e., to check whether the link between the two UEs is valid through signaling interaction. The UE at both ends of a PC5 unicast link can act as the initiator of the keep-alive procedure. When one UE acts as the initiating UE, the other UE is the target UE. Figure 1 is a schematic diagram for illustrating the PC5 unicast link keep-alive procedure. The link keep-alive procedure is as shown in Figure 1 The initiating UE triggers the link keep-alive procedure by maintaining a keep-alive timer T5003. Whenever the initiating UE receives the PC5 signaling or PC5 user data sent by the target UE, the initiating UE starts or restarts the T5003 timer. When T5003 expires, the initiating UE triggers the keep-alive procedure, i.e., sends a direct link keep-alive request message (DIRECT LINK KEEPALIVE REQUEST) to the target UE, while stopping T5003 and starting T5004. Before T5004 expires, if the direct link keep-alive response message (DIRECT LINK KEEPALIVE RESPONSE) from the target UE is received, T5004 is stopped and T5003 is started. When T5004 expires without receiving the link keep-alive response message from the target UE, the initiating UE retransmits the link keep-alive request message and starts T5004. When the retransmission reaches the maximum number of times, the initiating UE releases the PC5 unicast link. At the same time, the initiating UE can carry the maximum inactivity period in the direct link keep-alive request message, and the target UE starts the T5005 timer after receiving the message, and the target UE does not need to initiate the keep-alive procedure before T5005 expires.

[0056] When introducing sidelink DRX, the UE discontinuously monitors or receives the sidelink channel, so the related timers in the existing PC5 unicast link keep-alive process need to be extended to avoid unnecessary link keep-alive signaling process and possible link abnormal release.

[0057] In the following, several embodiments of how to extend the related timer duration of the PC5 unicast link keep-alive process after introducing sidelink DRX and how to trigger the extension of the timer and stop the extension of the timer are described in detail.

[0058] Embodiment 1

[0059] In Embodiment 1 of the present application, as shown in Figure 2 The steps performed by the user equipment UE include steps S101, S103, and S105.

[0060] In step S101, the AS layer of the UE determines (or obtains, or receives) the sidelink DRX parameter (including but not limited to DRX cycle, DRX cycle, etc.), and the method includes the following possibilities:

[0061] 1) According to the configuration of the base station: such as through system message or RRC dedicated signaling;

[0062] 2) According to pre-configuration;

[0063] 3) According to the service type or QoS characteristics indicated by the upper layer (i.e. V2X layer);

[0064] 4) According to the configuration of the opposite UE: through PC5 RRC message or MAC CE, etc.

[0065] 5) According to the result of negotiation with the opposite UE;

[0066] 6) According to the protocol specified value.

[0067] Among them, the AS layer of the UE can refer to the RRC layer or the MAC layer.

[0068] At the same time, the AS layer of the UE determines (or obtains, or receives) the sidelink DRX parameter can also be the result obtained by combining or comprehensively considering the sidelink DRX parameters in the above-mentioned various methods. For example, there are PC5 unicast links between the UE and multiple opposite UEs, and different sidelink DRX parameter configurations configured by multiple opposite UEs can be obtained, at this time, the UE can perform set operation, or intersection operation, or take the minimum value, or take the maximum value, etc. on multiple DRX parameters.

[0069] In the method, the UE determines (or obtains, or receives) the sidelink DRX parameter, and the method further comprises configuring the sidelink DRX parameter, or performing the sidelink DRX parameter, or using the sidelink DRX parameter, or configuring the DRX parameter to the lower layer.

[0070] Optionally, the AS layer of the UE can further determine whether to extend the link keep-alive timer according to the determined DRX parameter, or determine the time of extension or prolongation of the link keep-alive timer. For example, but not limited to, if the DRX cycle is configured, the link keep-alive timer is extended; or the time of extension of the link keep-alive timer is the time length of the DRX cycle in the DRX parameter; or if the DRX parameter is not configured or released, the time of extension of the link keep-alive timer is set to 0 or an invalid value.

[0071] In step S103, the AS layer of the UE notifies the upper layer (i.e. the V2X layer) of the first configuration information, wherein the first configuration information can include the following:

[0072] 1) part of the sidelink DRX parameter (i.e. one or several parameters in it): such as DRX cycle, DRX cycle, non-active time, etc.

[0073] 2) all of the sidelink DRX parameter;

[0074] 3) if the DRX parameter is not configured or released in step 101, the sidelink DRX cycle in the sidelink DRX information notified to the V2X layer is set to 0 or an invalid value;

[0075] 4) an indication of configuration of the sidelink DRX;

[0076] 5) an indication of extension (or prolongation, or adjustment) of the link keep-alive timer;

[0077] 6) the time of extension or prolongation of the link keep-alive timer;

[0078] 7) the time after the prolongation of the link keep-alive timer, i.e. the time length of the link keep-alive timer.

[0079] In the method, the AS layer of the UE can refer to the RRC layer or the MAC layer.

[0080] In step S105, the upper layer (i.e. the V2X layer) extends the time length of the PC5 unicast link keep-alive timer according to the first configuration information received from the AS layer.

[0081] For T5003, the possible timer time length extension method is at least one of the following methods:

[0082] 1) extend the value of T5003 by the sidelink DRX cycle (or DRX cycle) indicated in the first configuration information, i.e. the value of T5003 equals to the original value of T5003 plus the sidelink DRX cycle (or DRX cycle);

[0083] 2) extend the value of T5003 by the coefficient of the sidelink DRX cycle (or DRX cycle) indicated in the first configuration information, i.e. the value of T5003 equals to the original value of T5003 plus the coefficient of the sidelink DRX cycle (or DRX cycle), which can be an integer, a decimal or a fraction;

[0084] 3) extend the value of T5003 by the time of the link keep-alive timer extension or prolongation indicated in the first configuration information, i.e. the value of T5003 equals to the original value of T5003 plus the time of the link keep-alive timer extension or prolongation;

[0085] 4) extend the value of T5003 by the coefficient of the time of the link keep-alive timer extension or prolongation indicated in the first configuration information, i.e. the value of T5003 equals to the original value of T5003 plus the coefficient of the time of the link keep-alive timer extension or prolongation, which can be an integer, a decimal or a fraction;

[0086] 5) set the value of T5003 to the time of the link keep-alive timer extension indicated in the first configuration information;

[0087] 6) extend the value of T5003 by a certain fixed time.

[0088] For T5004, the possible timer duration extension methods are the same as those of T5003, and T5003 in the above-mentioned T5003 timer duration extension methods can be replaced by T5004, which will not be repeated here.

[0089] Embodiment 2

[0090] Based on Embodiment 1, in Embodiment 2 of the present application, as shown in FIG. 2, the steps performed by the user equipment UE include steps S201, S203 and S205. Figure 3

[0091] In step S201, the AS layer of the UE determines (or obtains, or receives) to stop (or release, or disable) the sidelink DRX, and the method includes the following possibilities:

[0092] 1) according to the configuration of the base station: such as releasing the sidelink DRX configuration through system message or RRC dedicated signaling;

[0093] 2) according to the service type or QoS characteristics indicated by the upper layer (i.e. V2X layer);

[0094] ​3) According to the configuration of the peer UE: releasing the sidelink DRX configuration through PC5 RRC message or MAC CE, etc.

[0095] 4) According to the result of negotiation with the peer UE.

[0096] Wherein, the AS layer of the UE can refer to the RRC layer or the MAC layer.

[0097] Optionally, the AS layer of the UE can also determine whether to stop the extended link keep-alive timer according to the determination of stopping the sidelink DRX. For example, but not limited to, if the DRX configuration is released, the extended link keep-alive timer is stopped.

[0098] In step S203, the AS layer of the UE notifies the upper layer (i.e. V2X layer) of the first stop information, wherein the first stop information can include the following possibilities:

[0099] 1) Sidelink DRX cycle (or DRX cycle), taking 0 or invalid value;

[0100] 2) Indication of stopping sidelink DRX;

[0101] 3) Indication of stopping extending (or prolonging, or adjusting) the link keep-alive timer;

[0102] 4) Time of extending or prolonging the link keep-alive timer duration, taking 0 or invalid value;

[0103] 5) Time after prolonging the link keep-alive timer duration, taking 0 or invalid value.

[0104] Wherein, the AS layer of the UE can refer to the RRC layer or the MAC layer.

[0105] In step S205, if the upper layer (i.e. V2X layer) receives the first stop information of the AS layer, the extended PC5 unicast link keep-alive timer duration is stopped. The value of T5003 is returned to the original T5003 value, or T5003 is not extended or prolonged. The value of T5004 is returned to the original T5004 value, or T5004 is not extended or prolonged.

[0106] Embodiment 3

[0107] Optionally, another implementation method of step 105 is that the upper layer (i.e. V2X layer) sets the link keep-alive timer T1 and T2 after adopting sidelink DRX according to the first configuration information received from the AS layer, and replaces T5003 with T1 and replaces T5004 with T2. In the unicast link protection process after adopting sidelink DRX, the start, restart and timeout processing of T1 are the same as T5003, and the start, restart and timeout of T2 are the same as T5004.

[0108] The method for setting the length of T1 is at least one of the following methods:

[0109] 1) setting the value of T1 as the value of T5003 plus the DRX cycle indicated in the first configuration information;

[0110] 2) setting the value of T1 as the value of T5003 plus the coefficient of the DRX cycle indicated in the first configuration information, which can be an integer, a decimal or a fraction;

[0111] 3) setting the value of T1 as the value of T5003 plus the time of the link keep-alive timer extension or prolongation indicated in the first configuration information;

[0112] 4) setting the value of T1 as the value of T5003 plus the coefficient of the time of the link keep-alive timer extension or prolongation indicated in the first configuration information, which can be an integer, a decimal or a fraction;

[0113] 5) setting T1 as the length of the link keep-alive timer prolongation indicated in the first configuration information;

[0114] 6) setting the value of T1 as the value of T5003 plus a certain fixed length.

[0115] The method for setting the length of T2 is at least one of the following methods:

[0116] 1) setting the value of T2 as the value of T5004 plus the DRX cycle indicated in the first configuration information;

[0117] 2) setting the value of T2 as the value of T5004 plus the coefficient of the DRX cycle indicated in the first configuration information, which can be an integer, a decimal or a fraction;

[0118] 3) setting the value of T2 as the value of T5004 plus the time of the link keep-alive timer extension or prolongation indicated in the first configuration information;

[0119] 4) setting the value of T2 as the value of T5004 plus the coefficient of the time of the link keep-alive timer extension or prolongation indicated in the first configuration information, which can be an integer, a decimal or a fraction;

[0120] 5) setting T2 as the length of the link keep-alive timer prolongation indicated in the first configuration information;

[0121] 6) setting the value of T2 as the value of T5004 plus a certain fixed length.

[0122] Embodiment 4

[0123] Alternatively, as another implementation method of step 205, the upper layer (i.e. V2X layer) stops using T1 and T2 control link keep-alive procedure and starts using T5003 and T5004 to control the procedure according to the first stop information received from the AS layer.

[0124] Figure 4 is a brief structure block diagram of the user equipment UE involved in the present application. As shown in Figure 4 the user equipment UE 400 includes a processor 401 and a memory 402. The processor 401 may, for example, include a microprocessor, a microcontroller, an embedded processor, etc. The memory 402 may, for example, include a volatile memory (such as a random access memory RAM), a hard disk drive (HDD), a non-volatile memory (such as a flash memory), or other memory, etc. The memory 402 stores program instructions thereon. The instructions, when executed by the processor 401, can perform the above-mentioned method executed by the user equipment detailed in the present application.

[0125] The program running on the device according to the present application can be a program that controls a central processing unit (CPU) to enable a computer to implement the functions of the embodiments of the present application. The program or information processed by the program can be temporarily stored in a volatile memory (such as a random access memory RAM), a hard disk drive (HDD), a non-volatile memory (such as a flash memory), or other memory systems.

[0126] The program for implementing the functions of the embodiments of the present application can be recorded on a computer readable recording medium. The corresponding functions can be implemented by causing a computer system to read the program recorded on the recording medium and execute the program. The so-called "computer system" here can be a computer system embedded in the device, which can include an operating system or hardware (such as a peripheral device). The "computer readable recording medium" can be a semiconductor recording medium, an optical recording medium, a magnetic recording medium, a short-time dynamic storage program recording medium, or any other computer readable recording medium.

[0127] The various features or functions of the devices used in the above-described embodiments can be implemented or performed by circuitry (e.g., a single chip or multiple chips). The circuitry designed to perform the functions described in this specification can include a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gates or transistor logic, discrete hardware components, or any combination thereof. The general-purpose processor can be a microprocessor, but in the alternative, the general-purpose processor can be any conventional processor, controller, microcontroller, or state machine. The circuitry can be a combination of digital and analog circuitry. Where the technology of the present application is incorporated into a new technology, new circuitry is created to implement the technology of the present application. The circuitry of one or more embodiments of the present application can be implemented or performed with a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in this specification.

[0128] Furthermore, the present application is not limited to the above-described embodiments. Although various examples of the embodiments have been described, the present application is not limited thereto. Fixed or non-mobile electronic devices installed indoors or outdoors can be used as terminal devices or communication devices, such as AV devices, kitchen devices, cleaning devices, air conditioners, office devices, automatic vending machines, and other home appliances.

[0129] As described above, the embodiments of the present application have been described in detail with reference to the accompanying drawings. However, the specific configuration is not limited to the above-described embodiments, and the present application includes any design modification without departing from the spirit of the present application. In addition, various modifications can be made to the present application within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in the different embodiments are also included in the technical scope of the present application. Furthermore, components described in the above-described embodiments having the same effect can be substituted for each other.

Claims

1. A method performed by a user equipment, comprising the steps of: determining sidelink DRX parameters by a radio access AS layer of the user equipment UE, informing first configuration information to a V2X layer of the UE by the radio access AS layer, the first configuration information comprising at least one of part of the sidelink DRX parameters, all of the sidelink DRX parameters, a DRX cycle set to 0 or an invalid value determined according to the sidelink DRX parameters, an indication of configuring the sidelink DRX parameters, an indication of extending a link keep alive timer, a length of extending the link keep alive timer, and a length after extending the link keep alive timer, and extending a length of a PC5 unicast link keep alive timer by the V2X layer according to the first configuration information. 2.The method of claim 1, wherein the method of determining sidelink DRX parameters by the radio access AS layer comprises at least one of the following methods: determining according to sidelink DRX configuration in system information or RRC dedicated signaling received from a base station; determining according to a traffic type or QoS characteristics indicated by the V2X layer; determining according to sidelink DRX configuration in a PC5 RRC message or MAC CE received from a peer UE; determining according to sidelink DRX configuration negotiated with the peer UE; and determining according to a protocol specified value. 3.The method of claim 1, further comprising the method of extending the length of the PC5 unicast link keep alive timer by the V2X layer after receiving the first configuration information comprises at least one of the following methods: extending the length of T5003 / T5004 timer by the DRX cycle indicated by the first configuration information; extending the length of T5003 / T5004 timer by the product of the DRX cycle indicated by the first configuration information and a coefficient; extending the length of T5003 / T5004 timer by the length of extending the link keep alive timer indicated by the first configuration information; extending the length of T5003 / T5004 timer by the product of the length of extending the link keep alive timer indicated by the first configuration information and a coefficient; setting the length of T5003 / T5004 timer to the length after extending the link keep alive timer indicated by the first configuration information; and extending the length of T5003 / T5004 timer by a fixed length. 4.A method performed by a user equipment, comprising the steps of: stopping sidelink DRX by a radio access AS layer of the user equipment UE, informing first stop information to a V2X layer of the UE by the radio access AS layer, the first stop information comprising at least one of an indication of stopping sidelink DRX, a sidelink DRX cycle set to 0 or an invalid value, an indication of stopping extending a link keep alive timer, a length of the link keep alive timer set to 0 or an invalid value, and a length of extending the link keep alive timer set to 0 or an invalid value, and stopping extending a length of a PC5 unicast link keep alive timer by the V2X layer according to the first stop information. ​ 5. The method of claim 4, wherein, the method for determining to stop sidelink DRX by the radio access AS layer comprises at least one of the following methods: releasing the sidelink DRX configuration according to a system message or RRC dedicated signaling received from the base station; releasing the sidelink DRX configuration according to a traffic type or QoS characteristic indicated by the V2X layer; releasing the sidelink DRX configuration according to a PC5 RRC message or MAC CE received from the peer UE; and releasing the sidelink DRX configuration according to a result of negotiation with the peer UE.

6. The method of claim 4, further comprising, the method for stopping extending the PC5 unicast link keep-alive timer duration by the V2X layer after receiving the sidelink DRX stop information comprises at least one of the following methods: stopping extending the duration of T5003 / T5004 timer; and returning the value of T5003 / T5004 to the original T5003 / T5004 value.

7. A user equipment comprising: a processor; and a memory storing instructions; wherein the instructions, when executed by the processor, perform the method of any one of claims 1 to 3; or the method of any one of claims 4 to 6.

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