CN116669100A

CN116669100A - Communication method and communication device

Info

Publication number: CN116669100A
Application number: CN202210460362.3A
Authority: CN
Inventors: 才宇; 徐海博; 薛丽霞
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2022-02-17
Filing date: 2022-04-28
Publication date: 2023-08-29

Abstract

A communication method and a communication device, the method comprising: the first terminal device transmits data to the second terminal device over a plurality of carriers over a side uplink SL; the method comprises the steps that a first terminal device determines feedback receiving conditions aiming at data on feedback receiving occasions on a plurality of carriers, wherein the feedback receiving occasions are feedback receiving occasions aiming at the data; and the first terminal equipment determines whether SL Radio Link Failure (RLF) occurs between the first terminal equipment and the second terminal equipment according to the feedback receiving condition. By adopting the application, when the transmission of one PC5-RRC connection is carried out on a plurality of carriers, the SL RLF is processed, thereby being beneficial to improving the reliability of communication.

Description

Communication method and communication device

Technical Field

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

Background

Starting from long term evolution (long term evolution, LTE), the third generation partnership project (the 3rd generation partnership project,3GPP) has been developing Sidelink (SL) standards for enabling direct communication between User Equipment (UE) and UEs in various use cases. Where the sidelink communication includes a unicast communication mode, specifically, in the unicast communication mode, a PC5-RRC (radio resource control) connection (PC 5-RRC connection) is generally required to be established between the source UE and the target UE, where one UE may have multiple PC5-RRC connections with one or more UEs. Currently, the transmission of one PC5-RRC connection is only performed on one carrier, and if the SL radio link fails (radio link failure, RLF) due to the one carrier, the terminal device releases the PC5-RRC connection. However, when transmission of one PC5-RRC connection is performed on a plurality of carriers, how to perform SL RLF processing has not yet proposed a solution, which reduces communication reliability.

Disclosure of Invention

The application provides a communication method and a communication device, which realize that SL RLF is processed when transmission of one PC5-RRC connection is carried out on a plurality of carriers, and are beneficial to improving the reliability of communication.

In a first aspect, the present application provides a communication method, which is applied to a first terminal device, the method comprising:

transmitting data to the second terminal device over a plurality of carriers over a side uplink SL;

determining feedback reception conditions of the data on feedback reception opportunities on the plurality of carriers, wherein the feedback reception opportunities are feedback reception opportunities of the data;

and determining whether SL Radio Link Failure (RLF) occurs between the first terminal equipment and the second terminal equipment according to the feedback receiving condition.

In the application, when the transmission of one PC5-RRC connection is carried out on a plurality of carriers, the SL RLF detection based on HARQ can be carried out on the plurality of carriers, and further, when the transmission of one PC5-RRC connection is carried out on the plurality of carriers, whether the SL radio link failure RLF occurs between the first terminal equipment and the second terminal equipment is determined. The data may be PSSCH or MAC PDU, the feedback for the data may be HARQ feedback or PSFCH, and the feedback reception occasion may be understood as a PSFCH feedback reception occasion.

In one possible implementation, the determining a feedback reception situation for the data on feedback reception occasions on the plurality of carriers includes:

determining whether feedback for the data is received on each feedback reception occasion on each of the plurality of carriers in turn;

the determining whether SL RLF occurs between the first terminal device and the second terminal device according to the feedback reception condition includes:

and if the first number of the feedback for the data which is not continuously received on the plurality of carriers is greater than or equal to a first threshold value, determining that SL RLF occurs between the first terminal equipment and the second terminal equipment.

In this implementation, when transmission of one PC5-RRC connection is performed on multiple carriers, PSFCH reception opportunities related to each PSSCH/MAC PDU transmission on each carrier may be counted together, and thus it may be determined whether SL RLF occurs on the PC5-RRC connection.

In one possible implementation, after the determining in turn whether feedback for the data is received on each feedback reception occasion on each of the plurality of carriers, the method further includes:

Setting a first number of feedback for the data to 0 if the first number is less than the first threshold and feedback for the data is received on a next feedback reception occasion;

if a first number of consecutive non-receipt of feedback for the data on the plurality of carriers is less than the first threshold and no feedback for the data is received on a next feedback reception occasion, then the first number is increased by 1.

determining whether feedback for the data is received on each feedback reception occasion on a first carrier in turn, wherein the first carrier is any one of the plurality of carriers;

and if the second number of the continuous non-received feedback for the data on the first carrier is greater than or equal to a second threshold, determining that SL RLF occurs between the first terminal device and the second terminal device on the first carrier.

In this implementation, when transmission of one PC5-RRC connection is performed on multiple carriers, PSFCH reception opportunities related to PSSCH/MAC PDU transmission on different carriers may be counted separately, so as to determine whether SL RLF occurs on a specific carrier on the PC5-RRC connection. In addition, when the PSFCH reception timing on any one carrier is counted in this implementation, the PSFCH reception timing may include a PSFCH reception timing corresponding to data sent on the carrier, and/or the PSFCH reception timing may also include a PSFCH reception timing corresponding to data sent on another carrier.

In one possible implementation, after the determining whether feedback for the data is received on each feedback reception occasion on the first carrier in turn, the method further includes:

setting a second number of feedback for the data to 0 if the second number is less than the second threshold on the first carrier continuously not received feedback for the data and feedback for the data is received on a next feedback reception occasion;

and if the second number of continuous non-receipt of feedback for the data on the first carrier is smaller than the second threshold value and the feedback for the data is not received on the next feedback receiving occasion, adding 1 to the second number.

determining whether feedback for the first data is received on each feedback reception occasion of the first data transmitted on the first carrier in turn, wherein the first carrier is any one of the plurality of carriers;

and if the third number of the feedback for the first data is not received continuously and is greater than or equal to a third threshold value, determining that SL RLF occurs between the first terminal equipment and the second terminal equipment on the first carrier.

In this implementation, when transmission of one PC5-RRC connection is performed on multiple carriers, PSFCH reception opportunities related to PSSCH/MAC PDU transmission on different carriers may be counted separately, so as to determine whether SL RLF occurs on a specific carrier on the PC5-RRC connection. In this implementation, when the PSFCH reception timing on any one carrier is counted, the PSFCH reception timing only includes the PSFCH reception timing corresponding to the data transmitted on the carrier.

In one possible implementation, after the sequentially determining whether feedback for the first data is received on each feedback reception occasion of the first data transmitted on the first carrier, the method further includes:

setting a third number of feedback for the first data to 0 if the third number is less than the third threshold and feedback for the first data is received on a next feedback reception occasion of the first data;

and if a third number of feedback for the first data is not continuously received on the first carrier and is smaller than the third threshold value, and feedback for the first data is not received on the next feedback receiving occasion of the first data, adding 1 to the third number.

In one possible implementation, the method further comprises:

and sending first indication information to the second terminal equipment, wherein the first indication information is used for indicating that the SL RLF occurs on the first carrier, or the first indication information is used for indicating that the first carrier is deleted or released.

In this implementation manner, when the first terminal device determines that the SL RLF occurs on the first carrier, the first terminal device may be configured to inform the second terminal device to delete or release the first carrier on which the SL RLF occurs by sending the first indication information to the second terminal device, so that unnecessary communication interruption caused by directly releasing the PC5-RRC connection when the SL RLF is found in the related art is reduced. That is, the embodiment of the application can determine the first carrier wave with the specific SL RLF, and only delete or release the first carrier wave when determining the first carrier wave with the specific SL RLF, while other carrier waves without the specific SL RLF can still be used for normal communication between the first terminal device and the second terminal device, thereby improving the reliability of communication.

In one possible implementation, the method further comprises:

deleting or releasing the first carrier.

In this implementation manner, when the first terminal device determines that the SL RLF occurs on the first carrier, the first terminal device may delete or release the first carrier on which the SL RLF occurs, which may save storage resources and is beneficial to improving reliability of communication.

In one possible implementation, the method further comprises:

and sending second indication information to access network equipment, wherein the second indication information is used for indicating the first carrier to generate SL RLF.

In this implementation manner, when the first terminal device determines that the SL RLF occurs in the first carrier, if there is an RRC connection between the first terminal device and the access network device, the first terminal device may further send second indication information to the access network device through the RRC connection to inform the access network device which carrier, in particular, the SL RLF occurs in the first carrier, so that the access network device may not schedule the first terminal device to send data to the second terminal device using the first carrier later, which is beneficial to improving reliability of communication.

In a second aspect, the present application provides a communication method, which is applied to a first terminal device, the method comprising:

Determining that a side uplink SL radio link failure RLF occurs on a first carrier, wherein the first carrier is any one or more of a plurality of carriers used by the first terminal equipment for sending data to a second terminal equipment;

and sending first indication information to the second terminal equipment, wherein the first indication information is used for indicating the first carrier, or the first indication information is used for indicating deletion or release of the first carrier.

In the application, when the first terminal equipment determines that the SL RLF occurs in the first carrier, the first terminal equipment can be used for informing the second terminal equipment of deleting or releasing the first carrier in which the SL RLF occurs by sending the first indication information to the second terminal equipment, so that unnecessary communication interruption caused by directly releasing the PC5-RRC connection when the SL RLF is discovered in the related art is reduced. That is, the embodiment of the application can determine the first carrier wave with the specific SL RLF, and only delete or release the first carrier wave when determining the first carrier wave with the specific SL RLF, while other carrier waves without the specific SL RLF can still be used for normal communication between the first terminal device and the second terminal device, thereby improving the reliability of communication.

In one possible implementation, the determining that SL RLF occurs on the first carrier includes:

and if the retransmission times of the data reach the maximum retransmission times based on the first Radio Link Control (RLC) entity, determining that SL RLF occurs on a first carrier associated with the first RLC entity, wherein the first terminal equipment sends the data to the second terminal equipment through the first RLC entity.

In such an implementation, the first terminal device determines that the transmission (including the initial transmission and the retransmission) of the RLC SDU for which the RLC entity reaches the maximum number of retransmissions is on one or more of the carriers, then the first terminal device may determine that the carrier causing the SL RLF is the one or more carriers associated with the RLC entity, that is, the first carrier is the one or more carriers associated with the first RLC entity.

In one possible implementation, the determining that the first carrier associated with the first RLC entity is SL RLF includes:

and if the retransmission times of the data reach the maximum retransmission times based on the first Radio Link Control (RLC) entity, and the first RLC entity is an RLC entity corresponding to a Packet Data Convergence Protocol (PDCP) entity using packet duplication, determining that SL RLF occurs on a first carrier associated with the first RLC entity.

In this implementation, if the RLC entity that causes SL RLF is one RLC entity corresponding to the PDCP entity using packet duplication, and the transmission of the RLC entity is mapped to one carrier set (it may also be understood that the carrier set corresponding to the logical channel corresponding to the RLC entity), the first terminal device may determine that the carrier on the carrier set causes SL RLF. That is, the first carrier is one or more carriers included in the carrier set.

In one possible implementation, the first carrier includes a plurality of carriers; after the determining that SL RLF occurs on the first carrier, the method further comprises:

respectively sending first information to the second terminal equipment on each carrier in the first carriers, wherein the first information is used for triggering the second terminal equipment to feed back second information;

and if the second information sent by the second terminal equipment is not received on a second carrier, determining that SL RLF occurs on the second carrier, wherein the second carrier is any one of the first carriers.

In such an implementation, once SL RLF occurs, the first terminal device sends first information to the peer UE (i.e., the second terminal device) on each of the first carriers, and receives second information from the second terminal device, which may be used to determine which of the first carriers, in particular, one or more, caused the SL RLF.

In one possible implementation, the method further comprises:

deleting or releasing the first carrier.

In one possible implementation, the method further comprises:

In a third aspect, the present application provides a communication apparatus, the apparatus being a first terminal device, the apparatus comprising:

A transmitting-receiving unit for transmitting data to the second terminal device over a plurality of carriers via the side uplink SL;

a processing unit, configured to determine a feedback reception situation for the data on feedback reception occasions on the multiple carriers, where the feedback reception occasions are reception occasions for feedback of the data;

and the processing unit is used for determining whether SL Radio Link Failure (RLF) occurs between the first terminal equipment and the second terminal equipment according to the feedback receiving condition.

In one possible implementation, the processing unit is configured to:

In one possible implementation, after determining, based on the processing unit, in turn, whether feedback for the data is received on each feedback reception occasion on each of the plurality of carriers, the processing unit is further configured to:

In one possible implementation, the processing unit is configured to:

In one possible implementation, the transceiver unit is further configured to:

In a possible implementation, the processing unit is further configured to:

deleting or releasing the first carrier.

In one possible implementation, the transceiver unit is further configured to:

In a fourth aspect, the present application provides a communication apparatus, the apparatus being a first terminal device, the apparatus comprising:

a processing unit, configured to determine that a side uplink SL radio link failure RLF occurs on a first carrier, where the first carrier is any one or more of multiple carriers used by the first terminal device to send data to a second terminal device;

the receiving and transmitting unit is configured to send first indication information to the second terminal device, where the first indication information is used to indicate the first carrier, or the first indication information is used to indicate deletion or release of the first carrier.

In one possible implementation, the processing unit is configured to:

In one possible implementation, the first carrier includes a plurality of carriers; after determining, based on the processing unit, that SL RLF is occurring on the first carrier, the processing unit is further configured to:

In a possible implementation, the processing unit is further configured to:

deleting or releasing the first carrier.

In one possible implementation, the transceiver unit is further configured to:

In a fifth aspect, the present application provides a communications apparatus, which may be a terminal device (e.g. a first terminal device or a second terminal device), or may be an apparatus in a terminal device, or may be an apparatus that is capable of being used in cooperation with a terminal device. The communication device may also be a chip system. The communication device may perform the method of the first and/or second aspect. The functions of the communication device can be realized by hardware, and can also be realized by executing corresponding software by hardware. The hardware or software includes one or more units or modules corresponding to the functions described above. The unit or module may be software and/or hardware. The operations and advantages performed by the communication device may be referred to the methods and advantages described in the first and/or second aspects, and the repetition is not repeated.

In a sixth aspect, the present application provides a communications apparatus, which may be a terminal device (e.g. a first terminal device or a second terminal device), the communications apparatus comprising a processor and a transceiver for executing a computer program or instructions stored in at least one memory to cause the apparatus to implement a method as in any one of the first and/or second aspects.

In a seventh aspect, the present application provides a communications apparatus, which may be a terminal device (e.g. a first terminal device or a second terminal device), comprising a processor, a transceiver and a memory. Wherein the processor, transceiver, and memory are coupled; the processor and transceiver are for implementing a method as in any one of the first and/or second aspects.

In an eighth aspect, the present application provides a computer readable storage medium having stored therein a computer program or instructions which, when executed by a computer, implement a method as in any of the first to fourth aspects.

In a ninth aspect, the present application provides a computer program product comprising instructions, the computer program product comprising computer program code for implementing the method of any one of the first to fourth aspects when the computer program code is run on a computer.

Drawings

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

FIG. 2 is a flow chart of a communication method according to an embodiment of the present application;

fig. 3 is a schematic diagram of a scenario for determining SL RLF according to an embodiment of the present application;

fig. 4 is another schematic diagram of a scenario for determining SL RLF according to an embodiment of the present application;

fig. 5 is another schematic diagram of a scenario for determining SL RLF according to an embodiment of the present application;

fig. 6 is another schematic diagram of a scenario for determining SL RLF according to an embodiment of the present application;

fig. 7a is a schematic diagram of another scenario for determining SL RLF according to an embodiment of the present application;

fig. 7b is another schematic diagram of a scenario for determining SL RLF according to an embodiment of the present application;

FIG. 8 is another flow chart of a communication method according to an embodiment of the present application;

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

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

Detailed Description

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

Wherein the terms "system" and "network" in embodiments of the application may be used interchangeably. Unless otherwise indicated, "/" indicates that the associated object is an "or" relationship, e.g., A/B may represent A or B; the "and/or" in the present application is merely an association relationship describing the association object, and indicates that three relationships may exist, for example, a and/or B may indicate: there are three cases, a alone, a and B together, and B alone, wherein a, B may be singular or plural. Also, in the description of the present application, unless otherwise indicated, "a plurality" means two or more than two. "at least one of" or the like means any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one (one) of a, b, or c may represent: a, b, c, a-b, a-c, b-c, or a-b-c, wherein a, b, c may be single or plural. In addition, in order to facilitate the clear description of the technical solution of the embodiments of the present application, in the embodiments of the present application, the words "first", "second", etc. are used to distinguish the same item or similar items having substantially the same function and effect. It will be appreciated by those of skill in the art that the words "first," "second," and the like do not limit the amount and order of execution, and that the words "first," "second," and the like do not necessarily differ.

Reference in the specification to "one embodiment" or "some embodiments" or the like means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," and the like in the specification are not necessarily all referring to the same embodiment, but mean "one or more but not all embodiments" unless expressly specified otherwise. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless expressly specified otherwise.

It should be understood that the technical solution of the embodiment of the present application may be applied to a long term evolution (long term evolution, LTE) architecture, a fifth generation mobile communication technology (5th generation mobile networks,5G), a wireless local area network (wireless local area networks, WLAN) system, a V2X communication system, and so on. The technical solution of the embodiment of the application can also be applied to other future communication systems, such as 6G communication systems, etc., in which the functions may remain the same, but the names may change.

The following describes an infrastructure of a communication system provided by an embodiment of the present application.

Referring to fig. 1, fig. 1 is a schematic diagram of a communication system according to an embodiment of the application. As shown in fig. 1, the communication system may include a first terminal apparatus 10 and a second terminal apparatus 20 that performs SL communication with the first terminal apparatus 10. Fig. 1 is only a schematic diagram, and does not limit the applicable scenario of the technical solution provided by the present application.

The first terminal device 10 and the second terminal device 20 are one entity for receiving signals or transmitting signals or receiving signals and transmitting signals at the user side. The first terminal device 10 and the second terminal device 20 are for providing one or more of a voice service and a data connectivity service to a user. The first terminal device 10 and the second terminal device 20 may be devices that include a radio transceiver function and may cooperate with an access network device to provide communication services for users. Specifically, the first terminal device 10 and the second terminal device 20 may refer to a User Equipment (UE), an access terminal, a subscriber unit, a subscriber station, a mobile station, a remote terminal, a mobile device, a terminal, a wireless communication device, a user agent, a user equipment, or a Road Side Unit (RSU). The first terminal device 10 and the second terminal device 20 may also be an unmanned aerial vehicle, an internet of things (internet of things, ioT) device, a Station (ST) in a WLAN, a cellular phone (cell phone), a smart phone (smart phone), a cordless phone, a wireless data card, a tablet, a session initiation protocol (session initiation protocol, SIP) phone, a wireless local loop (wireless local loop, WLL) station, a personal digital assistant (personal digital assistant, PDA) device, a laptop computer (laptop computer), a machine type communication (machine type communication, MTC) terminal, a handheld device with wireless communication functionality, a computing device or other processing device connected to a wireless modem, a vehicle-mounted device, a wearable device (also referred to as a wearable smart device), a Virtual Reality (VR) terminal, an augmented reality (augmented reality, AR) terminal, a wireless terminal in an industrial control (industrial control), a wireless terminal in a wireless medical service (wireless terminal), a smart terminal in a smart (smart) device, a smart mobile terminal in a smart network (smart mobile terminal), a smart mobile terminal in a smart phone (smart phone), a smart mobile terminal in a smart phone, etc. The first terminal device 10 and the second terminal device 20 may also be device-to-device (D2D) devices, such as electric meters, water meters, etc. The first terminal device 10 and the second terminal device 20 may also be terminals in a 5G system, or terminals in a next generation communication system, which is not limited in the embodiment of the present application.

It will be appreciated that the first terminal device 10 may also be in SL communication with a terminal device other than the second terminal device 20, and that the second terminal device 20 may also be in SL communication with a terminal device other than the first terminal device 10, without limitation.

Wherein the communication system may further comprise one or more access network devices 30 (only 1 is shown). In the present application, the first terminal device 10 and the second terminal device 20 may be located within the coverage area of the same access network device; or, the first terminal device 10 and the second terminal device 20 may be located within the coverage of different access network devices; or, the first terminal device 10 is located within the coverage area of the access network device, and the second terminal device 20 is located outside the coverage area (out of coverage) of the access network device; or, the first terminal device 10 is located outside the coverage area of the access network device, the second terminal device 20 is located within the coverage area of the access network device, and the like, which is not limited herein.

The access network device 30 is an entity on the network side for sending signals, or receiving signals, or sending signals and receiving signals. The access network device 30 may be a means deployed in a radio access network (radio access network, RAN) for providing wireless communication functions for the first terminal device 10 and the second terminal device 20, e.g. may be a transmission reception point (transmission reception point, TRP), a base station, various forms of control nodes. Such as a network controller, a radio controller in a cloud radio access network (cloud radio access network, CRAN) scenario, etc. Specifically, the access network device may be a macro base station, a micro base station (also referred to as a small station), a relay station, an Access Point (AP), a radio network controller (radio network controller, RNC), a Node B (NB), a base station controller (base station controller, BSC), a base transceiver station (base transceiver station, BTS), a home base station (e.g., home evolved nodeB, or home node B, HNB), a baseBand unit (BBU), a transmission point (transmitting and receiving point, TRP), a transmitting point (transmitting point, TP), a mobile switching center, or the like, or may be an antenna panel of the base station. The control node may connect to a plurality of base stations and configure resources for a plurality of terminals covered by the plurality of base stations. In systems employing different radio access technologies, the names of base station capable devices may vary. For example, the present application is not limited to specific names of access network devices, and may be an evolved base station (evolutional node B, eNB or eNodeB) in the LTE system, a radio controller in a cloud radio access network (cloud radio access network, CRAN) scenario, a gNB in 5G, or the access network device 30 may be a relay station, an access point, a vehicle-mounted device, a wearable device, a network side device in a network after 5G, or an access network device in a PLMN network of future evolution, or the like.

It should be noted that the technical solution provided by the embodiment of the present application is applicable to various system architectures. The network architecture and the service scenario described in the embodiments of the present application are for more clearly describing the technical solution of the embodiments of the present application, and do not constitute a limitation on the technical solution provided by the embodiments of the present application, and those skilled in the art can know that, with the evolution of the network architecture and the appearance of the new service scenario, the technical solution provided by the embodiments of the present application is applicable to similar technical problems.

In order to facilitate understanding of the relevant content of the embodiments of the present application, some of the knowledge needed for the scheme of the present application will be described below. It should be noted that these explanations are for easier understanding of the embodiments of the present application, and should not be construed as limiting the scope of protection claimed by the present application.

1. Side Link (SL)

SL is defined for direct communication between a terminal device and a terminal device. I.e. the link between the terminal device and the terminal device which communicates directly without forwarding through the base station.

The sidelink transmission is performed between a pair of sources (source) and destinations (destination). Source may be identified by a source layer 2 (layer-2) ID and destination may be identified by a destination layer-2 ID. The source layer-2ID identifies a sender (UE) of data in the sidelink communication, and destination layer-2ID identifies a target (or receiving UE) of data in the sidelink communication. The transmitting end refers to the source of the sidelink communication (or a MAC PDU), and the receiving end refers to the destination of the sidelink communication (or a MAC PDU). Wherein layer-2 is layer two.

UEs in the following description, including but not limited to, may refer to UEs identified using a layer-2ID that the UE uses in sidelink communications.

The sidelink communication includes a unicast communication mode, for which a PC5-RRC connection (PC 5-RRC connection) is a logical connection between two UEs of a pair of sourcelayer-2ID and destinationlayer-2 ID, which connection is considered to be established after the establishment of the corresponding PC5 unicast link. One UE may have multiple PC5-RRC connections with one or more UEs for different source and destination layer 2ID pairs.

2. PC5 reference point/interface

PC5 reference point/interface i.e. reference point/interface between UEs.

3. Uu reference point/interface

Uu reference point/interface i.e. the reference point/interface between UE and radio access network (e.g. NG-RAN, E-UTRAN).

4. Packet replication

NR side-chain communication may support side-chain packet duplication (packet duplication), performed at the PDCP layer of the UE. For side link packet duplication of transmissions, PDCP PDUs are duplicated at the PDCP entity. Duplicate PDCP PDUs of the same PDCP entity are submitted to two different RLC entities and associated to two different side link logical channels, respectively. Duplicate PDCP PDUs of the same PDCP entity are only allowed to be transmitted on different side-chain carriers. Different side chain logical channels corresponding to the same PDCP entity may be mapped onto carriers of different carrier sets. For example, the PDCP entity corresponds to logical channel 1 and logical channel 2, logical channel 1 being mapped to a carrier on carrier set 1, logical channel 2 being mapped to a carrier on carrier set 2. Wherein the number of carriers included in each carrier set may be 1 or more.

Starting from long term evolution (long term evolution, LTE), the third generation partnership project (the 3rd generation partnership project,3 GPP) has formulated a Sidelink (SL) standard for enabling direct communication between User Equipment (UE) and UEs in various use cases. Where the sidelink communication includes a unicast communication mode, specifically, in the unicast communication mode, a PC 5-radio resource control (radio resource control, RRC) connection (PC 5-RRC connection) is generally required to be established between the source UE and the target UE, where one UE may have multiple PC5-RRC connections with one or more UEs. Currently, the transmission of one PC5-RRC connection is only performed on one carrier, and if the SL radio link fails (radio link failure, RLF) due to the one carrier, the terminal device releases the PC5-RRC connection. However, no solution has been proposed as to how to perform SL RLF processing when transmission of one PC5-RRC connection is performed on multiple carriers.

Based on this, the embodiment of the application provides a communication method, which can realize that when the transmission of one PC5-RRC connection is carried out on a plurality of carriers, SL RLF is processed.

It should be noted that "feedback for data" in the embodiment of the present application may also be described as "feedback associated with data", and "receiving feedback on carrier" in the embodiment of the present application may also be described as "receiving feedback on carrier", etc., which are not limited herein.

It should be noted that "data" transmitted by the first terminal device to the second terminal device in the embodiment of the present application may be understood as a physical side uplink shared channel (physical sidelink shared channel, PSSCH) or a medium access control (medium access control, MAC) protocol data unit (protocol data unit, PDU). That is, the data involved in the embodiments of the present application may be carried for transmission on the PSSCH.

In the embodiment of the present application, "feedback for data" may be understood as "physical side uplink feedback channel (physical sidelink feedback channel, PSFCH) or hybrid automatic repeat request (hybrid automatic repeat request, HARQ) Acknowledgement (ACK) information", where the HARQ ACK information may be positive acknowledgement (positive acknowledgement) information, or negative acknowledgement (negative acknowledgement, NACK) information, etc., and is not limited herein. Alternatively, it may be appreciated that the feedback of data involved in embodiments of the present application may be carried for transmission over the PSFCH.

It should be noted that, the "feedback reception opportunity" in the embodiment of the present application may also be understood as "PSFCH reception opportunity".

It should be noted that "no feedback for data is received at a certain feedback reception opportunity on a certain carrier" described in the embodiment of the present application may also be described as "there is no PSFCH reception at a certain PSFCH reception opportunity on a certain carrier".

In addition, in the embodiments of the present application, the feedback of data (for example, data 1 transmitted on carrier 1) transmitted on a certain carrier (for example, carrier 1) may have the following 3 cases:

case 1: the feedback (e.g., feedback 1 for data 1, for example) may be transmitted entirely on the carrier on which the data is transmitted (i.e., carrier 1).

Case 2: the feedback (e.g., feedback 1 of data 1) may be transmitted entirely on another carrier than carrier 1, e.g., entirely on carrier 2; as another example, all are transmitted on carrier 3, etc.

Case 3: the feedback (e.g., feedback 1 of data 1) may be transmitted on multiple carriers (greater than or equal to 2 carriers), e.g., a portion of the feedback is transmitted on carrier 1 and another portion of the feedback is transmitted on the other carrier or carriers; for example, a portion of the feedback may be transmitted on carrier 2, another portion of the feedback may be transmitted on carrier 3 or one or more other carriers other than carrier 1, etc., as determined by the actual scenario and not limited herein. For convenience of description, the following embodiments of the present application mainly use data transmitted on one carrier, and feedback thereof may be transmitted on the carrier on which the data is transmitted. Or its feedback is all transmitted on the other carrier as an example.

It should be noted that, in the embodiments of the present application, the feedback reception timing included on a certain carrier (for example, carrier 1 is also taken as an example) may have the following 3 cases:

case 1: the feedback reception occasion included on carrier 1 may include only the feedback reception occasion corresponding to the data transmitted on carrier 1.

Case 2: the feedback reception opportunities included on carrier 1 may include only feedback reception opportunities corresponding to data transmitted on other carriers (i.e., carriers other than carrier 1, e.g., carrier 2, carrier 3, etc.).

Case 3: the feedback reception opportunities included on carrier 1 may include feedback reception opportunities corresponding to data transmitted on carrier 1 and feedback reception opportunities corresponding to data transmitted on other carriers.

It should be noted that, in the embodiment of the present application, the sidelink HARQ entity corresponding to the carrier may be described as a sidelink HARQ entity corresponding to PSSCH/MAC PDU transmission, or may be described as a sidelink HARQ entity corresponding to PSFCH reception timing, which is not limited herein.

It should be noted that, the RLC bearer described in the embodiment of the present application may be replaced by a logical channel, or the RLC bearer described in the embodiment of the present application may be replaced by an RLC entity.

In the embodiment of the present application, the first terminal device may be understood as a source terminal device or a data transmitting end, and the second terminal device may be described as an opposite terminal device of the first terminal device, or may be understood as a destination terminal device or a data receiving end.

It should be noted that, the initialization referred to in the embodiment of the present application may be described as being set to 0, and the re-initialization referred to in the embodiment of the present application may be also described as being (re) set to 0.

Note that, HARQ discontinuous transmission (discontinuous transmission, DTX) referred to in the embodiment of the present application may be understood as that feedback for one data is not received at a feedback reception occasion of the data.

In the embodiment of the present application, the data transmitted on one carrier at different times may be the same data or different data, which is not limited herein. The data transmitted on different carriers at the same time may be the same data or different data, and is not limited herein. The data transmitted on different carriers at different times may be the same data or different data, and is not limited herein. The data corresponding to the feedback reception timing at different times on one carrier may be the same data (e.g., the same PSSCH, or the same MAC PDU), or may be different data (e.g., different PSSCH, or different MAC PDU). The data corresponding to the feedback reception timing at the same time on different carriers may be the same data (e.g., the same PSSCH, or the same MAC PDU), or may be different data (e.g., different PSSCH, or different MAC PDU). The data corresponding to the feedback reception timing at different times on different carriers may be the same data (e.g., the same PSSCH, or the same MAC PDU), or may be different data (e.g., different PSSCH, or different MAC PDU).

The following describes the communication method and the communication device provided by the application in detail:

referring to fig. 2, fig. 2 is a flow chart of a communication method according to an embodiment of the application. The method may be performed by the first terminal device or may also be performed by a chip in the first terminal device, hereinafter collectively referred to as the first terminal device for convenience of description. The method shown in fig. 2 may include the following operations.

S201, the first terminal device transmits data to the second terminal device over a plurality of carriers via the side uplink SL.

In some embodiments, the first terminal device may transmit data to the second terminal device over a plurality of carriers via a Sidelink (SL), in particular, the first terminal device may transmit data to the second terminal device over a plurality of carriers via a PC5-RRC connection. Accordingly, the second terminal device may receive data from the first terminal device on a plurality of carriers. The data sent by the first terminal device on the multiple carriers may be different data, or the data sent by the first terminal device on the multiple carriers may also be the same data, which is not limited herein. For example, assume that multiple carriers include carrier 1, carrier 2, carrier 3, and carrier 4, where data 1 may be transmitted on carrier 1, data 2 may be transmitted on carrier 2, data 3 may be transmitted on carrier 3, and data 4 may be transmitted on carrier 4, where data 1, data 2, data 3, and data 4 are different. Alternatively, carrier 1, carrier 2, carrier 3, and carrier 4 may all be used to transmit data 1. In the following embodiments of the present application, data 1 is transmitted on carrier 1, data 2 is transmitted on carrier 2, data 3 is transmitted on carrier 3, and data 4 is transmitted on carrier 4. That is, all data transmitted on carrier 1 may be described as data 1, all data transmitted on carrier 2 may be described as data 2, all data transmitted on carrier 3 may be described as data 3, and all data transmitted on carrier 4 may be described as data 4. The data 1 transmitted on the carrier 1 at different times may be the same data, or may be different data, the data 2 transmitted on the carrier 2 at different times may be the same data, or may be different data, the data 3 transmitted on the carrier 3 at different times may be the same data, or may be different data, and the data 4 transmitted on the carrier 4 at different times may be the same data, or may be different data, which is not limited herein.

S202, the first terminal equipment determines feedback receiving conditions aiming at data on feedback receiving occasions on a plurality of carriers, and determines whether SL Radio Link Failure (RLF) occurs between the first terminal equipment and the second terminal equipment according to the feedback receiving conditions.

In some embodiments, the first terminal device may determine feedback reception conditions for the data on feedback reception occasions on the plurality of carriers. Specifically, the first terminal device may determine feedback reception conditions for data on feedback reception occasions on multiple carriers based on the MAC layer entity. Further, the first terminal device (or the MAC layer entity described as the first terminal device) may determine whether SL RLF occurs between the first terminal device and the second terminal device according to the feedback reception situation. Here, whether or not SL RLF occurs between the first terminal device and the second terminal device may also be described as whether or not SL RLF of the second terminal device occurs. It should be noted that, when determining that SL RLF occurs between the first terminal device and the second terminal device, the MAC layer entity of the first terminal device may also indicate to an upper layer (e.g., RRC layer of the first terminal device) that SL RLF is detected.

In one implementation (1), the determining feedback reception conditions for data at feedback reception timings on multiple carriers can be understood as follows: it is determined whether feedback for the data is received on each feedback reception occasion on each of the plurality of carriers in turn. That is, when the transmission of one PC5-RRC connection is performed on multiple carriers, PSFCH reception opportunities related to the transmission of each PSSCH/MAC PDU on each carrier are counted together, and the PSFCH reception opportunities on which carrier are not distinguished are not counted, wherein the counting manner may be that the PSFCH reception opportunities on the multiple carriers are processed according to the sequence of the PSFCH reception opportunities on the time domain. Optionally, the processing of each feedback receiving opportunity included in the multiple carriers may also be not limited to processing according to a sequence in a time domain, specifically determined according to an actual application scenario, which is not limited herein. For ease of understanding, the following is mainly described schematically by taking the processing performed in time-domain order as an example.

Further, the first terminal device may determine whether SL RLF occurs between the first terminal device and the second terminal device according to the feedback reception condition. Here, determining whether SL RLF occurs between the first terminal device and the second terminal device according to the feedback reception condition may be understood as: a first number (or first number may also be understood as a counter) is maintained for a PC5-RRC connection, the first number being initialized to 0. Once the PC5-RRC connection is established or (re) configured with the first threshold, the first number is (re) initialized to 0. Further, for each feedback reception opportunity included in the multiple carriers, processing each feedback reception opportunity according to the sequence in the time domain, and setting the first number to 0 when the first number of feedback for data is smaller than the first threshold value and feedback for data is received on the next feedback reception opportunity. When the first number of consecutive non-receipt of feedback for data on the plurality of carriers is less than a first threshold and no feedback for data is received on a next feedback reception occasion, the first number is increased by 1. And so on, determining that SL RLF occurs between the first terminal device and the second terminal device until a first number of consecutive non-receipt of feedback for the data on the plurality of carriers is greater than or equal to a first threshold. The first threshold may be configured by the network device (base station), or pre-configured, without limitation.

For example, referring to fig. 3, fig. 3 is a schematic diagram of a scenario for determining SL RLF according to an embodiment of the present application. As shown in fig. 3, the transmission of one PC5-RRC connection is performed on carrier 1, carrier 2, and carrier 3. Specifically, data 1 is transmitted on carrier 1, data 2 is transmitted on carrier 2, and data 3 is transmitted on carrier 3. The data 1 sent on the carrier 1 at different moments can be the same data or different data; the data 2 transmitted on the carrier 2 at different times may be the same data or different data; the data 3 transmitted on the carrier 3 at different times may be the same data or different data, and is not limited herein. In fig. 3, the feedback of data 1 is mainly transmitted on carrier 1, the feedback of data 2 is entirely transmitted on carrier 2, and the feedback of data 3 may be entirely transmitted on carrier 3 as illustrated schematically, which may be understood, or may not be limited to the feedback case shown in fig. 3, and is specifically determined according to the actual scenario, and is not limited herein. A variable a (i.e., a first number) is maintained for the PC5-RRC connection, the variable a being initialized to 0. Once the PC5-RRC connection is established or the first threshold is (re) configured, the variable a is (re) initialized to 0. Let the first threshold be 4.

Thus, the statistical procedure that does not distinguish which carrier the PSFCH receives the occasion is:

the PSFCH reception exists at the PSFCH reception timing 1 corresponding to the data 1, so the variable a is initialized to 0;

the PSFCH reception exists at the PSFCH reception timing 1 corresponding to the data 3, so the variable a is reinitialized to 0;

if PSFCH reception does not exist at PSFCH reception time 1 corresponding to the data 2, adding 1 to the variable a, wherein the variable a is equal to 1;

if PSFCH reception does not exist at PSFCH reception time 2 corresponding to the data 1, adding 1 to the variable a, wherein the variable a is equal to 2;

when PSFCH receiving exists at the PSFCH receiving time 2 corresponding to the data 3, the variable a is reinitialized to 0;

if PSFCH receiving time 2 corresponding to the data 2 does not exist PSFCH receiving, adding 1 to a variable a, wherein the variable a is equal to 1;

if PSFCH reception does not exist at PSFCH reception time 3 corresponding to the data 1, adding 1 to the variable a, wherein the variable a is equal to 2;

if PSFCH reception does not exist at PSFCH reception time 3 corresponding to the data 3, adding 1 to the variable a, wherein the variable a is equal to 3;

if there is no PSFCH reception at the PSFCH reception timing 4 corresponding to the data 1, the variable a is added with 1, and the variable a is equal to 4.

At this time, the variable a (i.e., the variable a=4) reaches the first threshold (i.e., 4), it is considered that SLRLF occurs between the first terminal device and the second terminal device.

If there is a time domain overlapping between the plurality of PSFCH reception timings, it is not limited to process which PSFCH reception timing is first, and a certain rule may be defined, for example, to process a PSFCH reception timing with earlier start time, and for example, to process a PSFCH reception timing with earlier end time, etc., which is not limited herein. In which, for ease of understanding, the PSFCH reception timing with earlier processing end time will be mainly described schematically.

For example, referring to fig. 4, fig. 4 is a schematic diagram of another scenario for determining SL RLF according to an embodiment of the present application. Wherein the first PSFCH reception occasion on carrier 1 shown in fig. 4 overlaps with the first PSFCH reception occasion on carrier 3 in the time domain. The processing rules may be processed sequentially in the order of PSFCH reception opportunities with earlier processing end times. As shown in fig. 4, transmission of one PC5-RRC connection is performed on carrier 1, carrier 2 and carrier 3, specifically, data 1 is transmitted on carrier 1, data 2 is transmitted on carrier 2, and data 3 is transmitted on carrier 3, where data 1 transmitted on carrier 1 at different times may be the same data, may be different data, and data 2 transmitted on carrier 2 at different times may be the same data, may be different data, and may be the same data, or may be different data, transmitted on carrier 3 at different times. The feedback for the data 1 is all transmitted on the carrier 1, the feedback for the data 2 is all transmitted on the carrier 2, and fig. 4 is mainly schematically illustrated by taking the example that the feedback for the data 3 may be all transmitted on the carrier 3, which can be understood that the feedback method is not limited to the feedback case shown in fig. 4, and is specifically determined according to the actual scenario, and is not limited herein. A variable b (i.e., a first number) is maintained for the PC5-RRC connection, the variable b being initialized to 0. Once the PC5-RRC connection is established or the first threshold is (re) configured, the variable b is (re) initialized to 0. Let the first threshold be 4.

Therefore, the statistical procedure of PSFCH reception opportunities earlier by the pre-processing end time and not distinguishing which carrier is the PSFCH reception opportunity is:

when PSFCH reception exists on the PSFCH reception occasion corresponding to the time T0, initializing a variable b to 0;

when PSFCH reception exists on the PSFCH reception occasion corresponding to the time T1, the variable b is reinitialized to 0;

when PSFCH receiving does not exist on the PSFCH receiving time corresponding to the moment T2, adding 1 to the variable b, wherein the variable b is equal to 1;

when PSFCH receiving does not exist on the PSFCH receiving time corresponding to the moment T3, adding 1 to the variable b, wherein the variable b is equal to 2;

when PSFCH reception exists on the PSFCH reception occasion corresponding to the time T4, the variable b is reinitialized to 0;

when PSFCH receiving does not exist on the PSFCH receiving time corresponding to the moment T5, adding 1 to the variable b, wherein the variable b is equal to 1;

when PSFCH receiving does not exist on the PSFCH receiving time corresponding to the moment T6, adding 1 to the variable b, wherein the variable b is equal to 2;

when PSFCH receiving does not exist on the PSFCH receiving time corresponding to the moment T7, adding 1 to the variable b, wherein the variable b is equal to 3;

and if PSFCH receiving time corresponding to the time T8 does not exist PSFCH receiving, adding 1 to the variable b, and enabling the variable b to be equal to 4.

At this time, the variable b (i.e., the variable b=4) reaches the first threshold, and it is considered that SLRLF occurs between the first terminal device and the second terminal device.

In general, one carrier may correspond to one sidelink HARQ entity. For example, carrier 1 corresponds to sidelink HARQ entity 1, carrier 2 corresponds to sidelink HARQ entity 2, and carrier 3 corresponds to sidelink HARQ entity 3. In implementation (1), the logic body for performing the addition or (re) initialization on the variable (i.e., the first number) corresponding to the plurality of carriers may be any one of the plurality of sidelink HARQ entities corresponding to the plurality of carriers, for example, the sidelink HARQ entity 1 or the sidelink HARQ entity 2 or the sidelink HARQ entity 3.

In another implementation manner (2), the determining feedback reception conditions for data on feedback reception occasions on multiple carriers can be further understood as: whether feedback for data is received on each feedback reception occasion on a first carrier is determined in turn, wherein the first carrier is any one of a plurality of carriers. The determining manner may be performed according to the time-domain sequence of all the PSFCH receiving opportunities included in each carrier, or may not be performed according to the time-domain sequence, which is not limited herein. For ease of understanding, the following description will be made mainly by taking the sequential processing in the time domain as an example.

Specifically, a case 3 will be described below as an example of feedback reception timing included in a certain carrier. That is, the above-described determination of whether feedback for data is received on each feedback reception occasion on the first carrier in turn can be understood as: and sequentially determining whether feedback for the data is received on all feedback reception occasions included on the first carrier. All feedback reception opportunities here include both feedback reception opportunities corresponding to the first data transmitted on the first carrier and feedback reception opportunities corresponding to the data transmitted on the other carriers.

Further, the first terminal device may determine whether SL RLF occurs between the first terminal device and the second terminal device according to the feedback reception condition. Here, determining whether SL RLF occurs between the first terminal device and the second terminal device according to the feedback reception condition may be understood as: a second number (or second number may also be understood as a counter) is maintained for each carrier in a PC5-RRC connection, the second number being initialized to 0. Once the PC5-RRC connection is established or (re) configured with the second threshold, or the first carrier is configured, or activated, the second number is (re) initialized to 0. Further, for each feedback receiving opportunity included in the first carrier, processing each feedback receiving opportunity according to the sequence in the time domain, and setting the second number to 0 when the second number of feedback for data is smaller than the second threshold value and feedback for data is received at the next feedback receiving opportunity; when the second number of consecutive non-receipt of feedback for data on the first carrier is less than the second threshold and no feedback for data is received on the next feedback reception occasion, the second number is added by 1. And so on, determining that SL RLF occurs between the first terminal device and the second terminal device on the first carrier until a second number of consecutive non-receipt of feedback for the data on the first carrier is greater than or equal to a second threshold. Here, the occurrence of SL RLF on the first carrier between the first terminal device and the second terminal device may also be cleaved such that the continuous HARQ DTX of the second terminal device on the first carrier reaches a maximum number.

Alternatively, in one embodiment, SL RLF is considered to occur between the first terminal device and the second terminal device when continuous HARQ DTX occurs a maximum number of times for each of all carriers from which the first terminal device transmits data to the second terminal device.

Alternatively, in one embodiment, when the continuous HARQ DTX does not occur for the partial carrier of the data transmitted by the first terminal device to the second terminal device for the maximum number of times, it is considered that no SL RLF occurs between the first terminal device and the second terminal device.

The second threshold may be configured by the network device (base station), or pre-configured, without limitation. It should be noted that, in the embodiment of the present application, the second threshold may be configured for different carriers respectively. In another embodiment, the same second threshold may also be used for different carriers. The first threshold value may be the same as the second threshold value, or the first threshold value may be different from the second threshold value, and the present application is not limited thereto.

For example, please refer to fig. 5, fig. 5 is another schematic diagram of a scenario for determining SL RLF according to an embodiment of the present application. As shown in fig. 5, one PC5-RRC connection may send data on carrier 1, carrier 2 and carrier 3, specifically, send data 1 on carrier 1, send data 2 on carrier 2 and send data 3 on carrier 3, where data 1 sent on carrier 1 at different times may be the same data, may be different data, and may be the same data as data 2 sent on carrier 2 at different times, and may be different data, and may be the same data as data 3 sent on carrier 3 at different times. In fig. 5, feedback of data 1 is mainly transmitted on carrier 1, feedback of data 2 may be transmitted on carrier 1, feedback of data 3 may be transmitted on carrier 3, and it is understood that the feedback is not limited to the feedback case shown in fig. 5, and is specifically determined according to an actual scenario, and is not limited herein. Thus, one variable may be maintained for carrier 1, carrier 2, carrier 3, respectively, i.e., for carrier 1, for carrier 2, for carrier 3, where variable c, d, and e are initialized to 0, where both variable c, d, and e may be understood as a second number. Assume that the second threshold is 5. Wherein:

1. On carrier 1, carrier 1 includes PSFCH reception opportunities corresponding to data 1 and data 2. Thus, the statistical procedure for all feedback reception opportunities on carrier 1 is:

when PSFCH reception exists on PSFCH reception time 1 corresponding to the data 1, the variable c is reinitialized to 0;

if PSFCH reception does not exist at PSFCH reception time 1 corresponding to data 2, adding 1 to variable c, wherein variable c is equal to 1;

if PSFCH reception does not exist at PSFCH reception time 2 corresponding to the data 1, adding 1 to the variable c, wherein the variable c is equal to 2;

if PSFCH reception does not exist at PSFCH reception opportunity 2 corresponding to data 2, adding 1 to variable c, wherein variable c is equal to 3;

if PSFCH reception does not exist at PSFCH reception time 3 corresponding to the data 1, adding 1 to the variable c, wherein the variable c is equal to 4;

and if PSFCH receiving does not exist on the PSFCH receiving time 4 corresponding to the data 1, adding 1 to the variable c, and enabling the variable c to be equal to 5.

At this time, the variable c (i.e., the variable c=5) reaches the second threshold, it is determined that SL RLF occurs on the carrier 1 between the first terminal device and the second terminal device.

2. On carrier 2, there is no PSFCH reception occasion for any data, so the statistics for all feedback reception occasions on carrier 2 are: the variable d is 0.

At this time, the variable d (i.e., the variable d=0) does not reach the second threshold, it is determined that SL RLF does not occur on the carrier 2 between the first terminal device and the second terminal device.

3. On carrier 3, carrier 3 only includes PSFCH reception opportunities corresponding to data 3. Thus, the statistical procedure for all feedback reception opportunities on carrier 3 is:

when PSFCH receiving exists at PSFCH receiving time 1 corresponding to data 3, the variable e is reinitialized to 0;

when PSFCH receiving exists at the PSFCH receiving time 2 corresponding to the data 3, the variable e is reinitialized to 0;

and if PSFCH receiving time 3 corresponding to the data 3 does not exist PSFCH receiving, adding 1 to the variable e, wherein the variable e is equal to 1.

At this time, the variable e (i.e., the variable e=1) does not reach the second threshold, it is determined that SL RLF does not occur on the carrier 3 between the first terminal device and the second terminal device. The absence of SL RLF on carrier 3 between the first terminal device and the second terminal device may also be cleaved as the continuous HARQ DTX of the second terminal device on carrier 3 not reaching the maximum number.

Note that if there is no feedback reception timing on a certain carrier, statistics may not be performed on the carrier. That is, in the above example, the variable d need not be maintained for carrier 2.

In general, one carrier may correspond to one sidelink HARQ entity. For example, carrier 1 corresponds to sidelink HARQ entity 1, carrier 2 corresponds to sidelink HARQ entity 2, and carrier 3 corresponds to sidelink HARQ entity 3. In implementation (2), the logical body of adding or (re) initializing the variable corresponding to a certain carrier may be a sidelink HARQ entity corresponding to the carrier. The logic body for performing the addition or (re) initialization of the variable corresponding to a certain carrier may include a sidelink HARQ entity corresponding to data (which may be data transmitted on other carriers) related to the feedback reception timing on the carrier. That is, the logic body for counting the feedback reception condition of a certain carrier may be a sidelink HARQ entity corresponding to the carrier. For example, the logical body for counting the feedback reception situation of the carrier 1 may be the sidelink HARQ entity 1, the logical body for counting the feedback reception situation of the carrier 2 may be the sidelink HARQ entity 2, and the logical body for counting the feedback reception situation of the carrier 3 may be the sidelink HARQ entity 3. The sidelink HARQ entity corresponding to one carrier may be understood as a sidelink HARQ entity corresponding to data sent on the carrier. Alternatively, the sidelink HARQ entity corresponding to one carrier may be understood as a sidelink HARQ entity corresponding to a feedback reception opportunity on the carrier.

The logic body for performing addition or (re) initialization on the variable corresponding to a certain carrier may further include a sidelink HARQ entity corresponding to data (the data may be data sent on other carriers) related to the feedback reception timing on the carrier. For example, the logical body for counting the feedback reception situation of the carrier 1 may be a sidelink HARQ entity 1 and a sidelink HARQ entity corresponding to the data sent on the carrier 2.

In another implementation manner (3), the determining feedback reception conditions for data on feedback reception occasions on multiple carriers can be further understood as: it is determined in turn whether feedback for the first data is received at each feedback reception occasion of the first data transmitted on a first carrier, wherein the first carrier is any one of a plurality of carriers. Here the first data is the data transmitted on the first carrier. The determining manner may be processing according to the sequence of the PSFCH reception opportunity of the PSSCH/MAC PDU sent on each carrier in the time domain, or may not be processing according to the sequence in the time domain, which is not limited herein. For ease of understanding, the following description will be made mainly by taking the sequential processing in the time domain as an example.

Note that, each feedback reception timing of the first data sent on the first carrier may be on one or more carriers, and the one or more carriers may or may not include the first carrier, which is not limited herein. Alternatively, each feedback reception occasion of the first data transmitted on the first carrier may include only the feedback reception occasion on the first carrier. Each feedback reception occasion of the first data transmitted on the first carrier may be exemplified on one or more carriers.

Further, the first terminal device may determine whether SL RLF occurs between the first terminal device and the second terminal device according to the feedback reception condition. Here, determining whether SL RLF occurs between the first terminal device and the second terminal device according to the feedback reception condition may be understood as: a third number (or third number may also be understood as a counter) is maintained for each carrier in a PC5-RRC connection, the third number being initialized to 0. Once the PC5-RRC connection is established or (re) configured with the third threshold, either the first carrier is configured or the first carrier is activated, the third number is (re) initialized to 0. Further, for each feedback reception opportunity of the first data sent on the first carrier, processing each feedback reception opportunity of the first data according to the sequence in the time domain, and setting the third number to 0 when the third number of feedback for the first data is smaller than the third threshold value and feedback for the first data is received on the next feedback reception opportunity of the first data continuously not received on the first carrier; when the third number of consecutive non-receipt of feedback for the first data on the first carrier is less than the third threshold and no feedback for the first data is received on a next feedback reception occasion of the first data, the third number is added by 1. And so on, determining that SL RLF occurs on the first carrier between the first terminal device and the second terminal device until a third amount of feedback for the first data is continuously not received greater than or equal to a third threshold. Here, the occurrence of SL RLF on the first carrier between the first terminal device and the second terminal device may also be cleaved such that the continuous HARQ DTX of the second terminal device on the first carrier reaches a maximum number.

The third threshold may be configured by the network device (base station), or pre-configured, without limitation. It should be noted that, in the embodiment of the present application, the third threshold may be configured for different carriers. In another embodiment, the same third threshold may also be used for different carriers. It should be noted that the first threshold value, the second threshold value and the third threshold value may be different from each other; alternatively, the first threshold, the second threshold, and the third threshold may be partially the same, e.g., the first threshold and the second threshold may be the same, and the third threshold and the first threshold (or the second threshold) may be different; alternatively, the first threshold, the second threshold, and the third threshold may be the same, and are not limited herein.

For example, referring to fig. 6, fig. 6 is a schematic diagram of another scenario for determining SL RLF according to an embodiment of the present application. As shown in fig. 6, one PC5-RRC connection may send data on carrier 1, carrier 2 and carrier 3, specifically, send data 1 on carrier 1, send data 2 on carrier 2 and send data 3 on carrier 3, where data 1 sent on carrier 1 at different times may be the same data, may be different data, and may be the same data as data 2 sent on carrier 2 at different times, and may be the same data as data 3 sent on carrier 3 at different times, may be different data, which is not limited herein. In fig. 6, the feedback of data 1 is mainly transmitted on carrier 1, the feedback of data 2 may be transmitted on carrier 1, and the feedback of data 3 is schematically illustrated as being transmitted on carrier 3, which may be understood that the feedback is not limited to the feedback case shown in fig. 6, and is specifically determined according to the actual scenario, and is not limited herein. Thus, one variable may be maintained for carrier 1, carrier 2, carrier 3, respectively, i.e., for carrier 1, for carrier 2, for carrier 3, where variable f, variable g, and variable h are initialized to 0, where variable f, variable g, and variable h may be understood as a third number. Assume that the third threshold is 3. Wherein:

1. The statistical process for the PSFCH reception opportunity corresponding to the data 1 sent on the carrier 1 is:

on carrier 1, when PSFCH reception exists on PSFCH reception opportunity 1 corresponding to data 1, variable f is 0;

if PSFCH reception does not exist at PSFCH reception time 2 corresponding to the data 1, adding 1 to the variable f, wherein the variable f is equal to 1;

if PSFCH reception does not exist at PSFCH reception time 3 corresponding to the data 1, adding 1 to the variable f, wherein the variable f is equal to 2;

and if PSFCH receiving does not exist on the PSFCH receiving time 4 corresponding to the data 1, adding 1 to the variable f, wherein the variable f is equal to 3.

At this time, the variable f (i.e., the variable f=3) reaches the third threshold, it is determined that SL RLF occurs on the carrier 1 between the first terminal device and the second terminal device.

2. The statistical process for the PSFCH reception opportunity corresponding to the data 2 sent on carrier 2 is:

on carrier 1, if PSFCH reception does not exist at PSFCH reception time 1 corresponding to data 2, adding 1 to variable g, wherein variable g is equal to 1;

and if PSFCH receiving time 2 corresponding to the data 2 does not exist PSFCH receiving, adding 1 to the variable g, wherein the variable g is equal to 2.

At this time, the variable g (i.e., the variable g=2) does not reach the third threshold, it is determined that SL RLF does not occur on the carrier 2 between the first terminal device and the second terminal device. The absence of SL RLF on carrier 2 between the first terminal device and the second terminal device may also be cleaved as the continuous HARQ DTX of the second terminal device on carrier 2 not reaching the maximum number.

3. The statistical process for the PSFCH reception opportunity corresponding to the data 3 sent on the carrier 3 is:

on carrier 3, when PSFCH reception exists at PSFCH reception time 1 corresponding to data 3, the variable h is reinitialized to 0;

when PSFCH receiving exists at the PSFCH receiving time 2 corresponding to the data 3, the variable h is reinitialized to 0;

and if PSFCH receiving time 3 corresponding to the data 3 does not exist PSFCH receiving, adding 1 to the variable h, wherein the variable h is equal to 1.

At this time, the variable h (i.e., the variable h=1) does not reach the third threshold, it is determined that SL RLF does not occur on the carrier 3 between the first terminal device and the second terminal device. The absence of SL RLF on carrier 3 between the first terminal device and the second terminal device may also be cleaved as the continuous HARQ DTX of the second terminal device on carrier 3 not reaching the maximum number.

In general, one carrier may correspond to one sidelink HARQ entity. For example, carrier 1 corresponds to sidelink HARQ entity 1, carrier 2 corresponds to sidelink HARQ entity 2, and carrier 3 corresponds to sidelink HARQ entity 3. In implementation (3), the logical body for performing addition or (re) initialization on the variable corresponding to a certain carrier may be a sidelink HARQ entity corresponding to the carrier. That is, the logic body for counting the feedback reception condition of a certain carrier may be a sidelink HARQ entity corresponding to the carrier. For example, the logical body for counting the feedback reception situation of the carrier 1 may be the sidelink HARQ entity 1, the logical body for counting the feedback reception situation of the carrier 2 may be the sidelink HARQ entity 2, and the logical body for counting the feedback reception situation of the carrier 3 may be the sidelink HARQ entity 3. The sidelink HARQ entity corresponding to one carrier may be understood as a sidelink HARQ entity corresponding to data sent on the carrier. Alternatively, the sidelink HARQ entity corresponding to one carrier may be understood as a sidelink HARQ entity corresponding to a feedback reception opportunity on the carrier.

In another implementation (4), the plurality of carriers used for data transmission may be grouped and counted, that is, the plurality of carriers used for data transmission may be divided into a plurality of carrier groups, and counted for each carrier group, where carriers included in different carrier groups may be different. The first carrier set may be any one of a plurality of carrier sets. For example, assume that the plurality of carriers includes carrier 1, carrier 2, carrier 3, and carrier 4, where carrier 1 and carrier 2 may constitute carrier set 1, and carrier 3 and carrier 4 may constitute carrier set 2.

Specifically, the following 2 statistical approaches may exist under implementation (4) above:

the first statistical method is to count feedback reception conditions of all feedback reception opportunities on the first carrier group. That is, the above-described determination of feedback reception conditions for data on feedback reception opportunities on a plurality of carriers can also be understood as: it is determined whether feedback for the data is received on each feedback reception occasion on each carrier in the first carrier group in turn. The first carrier group may include 2 or more carriers, and the 2 or more carriers included in the first carrier group may be included in the plurality of carriers. The above-mentioned determination of whether feedback for data is received on each feedback reception occasion on the first carrier group in turn can be understood as: and sequentially determining whether feedback for the data is received on all feedback reception occasions included on the first carrier group. All feedback reception opportunities here include both feedback reception opportunities corresponding to data transmitted on the first carrier group and feedback reception opportunities corresponding to data transmitted on other carrier groups.

Further, the first terminal device may determine whether SL RLF occurs between the first terminal device and the second terminal device according to the feedback reception condition. Here, determining whether SL RLF occurs between the first terminal device and the second terminal device according to the feedback reception condition may be understood as: for a PC5-RRC connection, a fourth number is maintained for each of the different carrier groups, the fourth number being initialized to 0. Once the PC5-RRC connection is established, or the fourth threshold is (re) configured, or the fourth set of carriers is (re) activated, or any one of the fourth set of carriers is (re) configured, or any one of the fourth set of carriers is (re) activated, the fourth number is (re) initialized to 0. Processing each feedback receiving opportunity according to the sequence in the time domain for all feedback receiving opportunities included in the first carrier group, and setting the fourth number to 0 when the fourth number of feedback for data which is not continuously received on the first carrier group is smaller than a fourth threshold value and feedback for data is received on the next feedback receiving opportunity; when the fourth number of consecutive non-receipt of feedback for data on the first carrier group is less than the fourth threshold and no feedback for data is received on the next feedback reception occasion, the fourth number is increased by 1. And so on, until a fourth number of consecutive non-received feedback for data on the first carrier group is greater than or equal to a fourth threshold, determining that SL RLF occurs between the first terminal device and the second terminal device on the first carrier group.

Here, the occurrence of SL RLF on the first carrier group between the first terminal device and the second terminal device may also be cleaved such that the continuous HARQ DTX of the second terminal device on the first carrier group reaches a maximum number.

In one embodiment, SL RLF is considered to occur between the first terminal device and the second terminal device when continuous HARQ DTX occurs a maximum number of times for each of all the carrier groups that the first terminal device transmits data to the second terminal device.

In one embodiment, when the continuous HARQ DTX does not occur for the partial carrier set for the first terminal device to transmit data to the second terminal device up to the maximum number of times, it is considered that no SL RLF occurs between the first terminal device and the second terminal device.

The fourth threshold may be configured by the network device (base station) or pre-configured (pre-configuration), without limitation. It should be noted that, in the embodiment of the present application, the fourth threshold may be configured for each of different carrier waves. In another embodiment, the same fourth threshold may also be used for different carrier groups. It should be noted that the first threshold value, the second threshold value, the third threshold value and the fourth threshold value may be different from each other; alternatively, the first threshold, the second threshold, the third threshold, and the fourth threshold may be partially identical, e.g., the first threshold and the second threshold may be identical, and the third threshold, the fourth threshold, and the first threshold (or the second threshold) may each be different; alternatively, the first threshold, the second threshold, the third threshold and the fourth threshold may be the same, and are not limited herein.

For example, referring to fig. 7a, fig. 7a is a schematic diagram of another scenario for determining SL RLF according to an embodiment of the present application. As shown in fig. 7a, one PC5-RRC connection may send data on carrier 1, carrier 2, carrier 3 and carrier 4, specifically, data 1 on carrier 1, data 2 on carrier 2, data 3 on carrier 3 and data 4 on carrier 4, where data 1 sent on carrier 1 at different times may be the same data, may also be different data, data 2 sent on carrier 2 at different times may be the same data, may also be different data, data 3 sent on carrier 3 at different times may be the same data, may also be different data, and data 4 sent on carrier 4 at different times may be the same data, may also be different data, where no limitation is made. In fig. 7a, the feedback of data 1 is mainly transmitted on carrier 1, the feedback of data 2 is transmitted on carrier 2, the feedback of data 3 is transmitted on carrier 1, and the feedback of data 4 is transmitted on carrier 4, which is an example. Wherein, a variable i can be maintained for carrier group 1 consisting of carrier 1 and carrier 2, and a variable j can be maintained for carrier group 2 consisting of carrier 3 and carrier 4, and the variable i and the variable j are initialized to 0. Here, the variables i and j can be understood as a fourth number. That is, the feedback condition statistics may be performed by dividing the carrier 1 and the carrier 2 into the carrier group 1, and dividing the carrier 3 and the carrier 4 into the carrier group 2. Let the fourth threshold be 4. Wherein:

1. On carrier group 1, carrier 1 in carrier group 1 includes PSFCH reception opportunities corresponding to data 1, and carrier 2 in carrier group 1 includes PSFCH reception opportunities corresponding to data 2 and data 3. Therefore, the statistical process for all feedback reception opportunities on carrier group 1 is:

when PSFCH reception exists on PSFCH reception time 1 corresponding to the data 1, initializing a variable i to 0;

when PSFCH reception exists on PSFCH reception time 1 corresponding to data 3, the variable i is reinitialized to 0;

if PSFCH reception does not exist at PSFCH reception time 1 corresponding to data 2, adding 1 to variable i, wherein variable i is equal to 1;

when PSFCH reception exists on PSFCH reception time 2 corresponding to the data 1, the variable i is reinitialized to 0;

when PSFCH reception exists on PSFCH reception time 2 corresponding to the data 3, the variable i is reinitialized to 0;

if PSFCH reception does not exist at PSFCH reception time 2 corresponding to the data 2, adding 1 to the variable i, wherein the variable i is equal to 1;

if PSFCH reception does not exist at PSFCH reception time 3 corresponding to the data 1, adding 1 to the variable i, wherein the variable i is equal to 2;

if PSFCH reception does not exist at PSFCH reception time 3 corresponding to the data 3, adding 1 to the variable i, wherein the variable i is equal to 3;

and if PSFCH receiving does not exist at the PSFCH receiving time 4 corresponding to the data 1, adding 1 to the variable i, wherein the variable i is equal to 4.

At this time, the variable i (i.e., the variable i=4) reaches the fourth threshold, it is determined that SL RLF occurs on the carrier group 1 between the first terminal device and the second terminal device.

2. On carrier group 2, carrier 3 in carrier group 2 does not include any PSFCH reception opportunity corresponding to data, and carrier 4 in carrier group 2 includes a PSFCH reception opportunity corresponding to data 4. Therefore, the statistical process for all feedback reception opportunities on carrier group 2 is:

if PSFCH reception does not exist on PSFCH reception opportunity 1 corresponding to data 4, initializing a variable j to 0;

if PSFCH reception does not exist at PSFCH reception time 2 corresponding to the data 4, adding 1 to the variable j, wherein the variable j is equal to 1;

when the PSFCH reception exists at the PSFCH reception timing 3 corresponding to the data 4, the variable j is reinitialized to 0.

At this time, the variable j (i.e., the variable j=0) does not reach the fourth threshold, it is determined that SL RLF does not occur on the carrier group 2 between the first terminal device and the second terminal device. The absence of SL RLF on carrier set 2 between the first terminal device and the second terminal device may also be cleaved as the maximum number of consecutive HARQ DTX's for the second terminal device on carrier set 2.

The second statistical method is to count feedback reception conditions of feedback reception occasions corresponding to the first carrier group data transmitted on the first carrier group. That is, the above-described determination of feedback reception conditions for data on feedback reception opportunities on a plurality of carriers can also be understood as: and determining whether feedback for the first carrier group data is received at each feedback reception opportunity of the first carrier group data transmitted on the first carrier group in turn, wherein the first carrier group is any one of a plurality of carriers. The first carrier set data is herein referred to as data transmitted on the first carrier set, that is, all data transmitted on the first carrier set are described as first carrier set data. Further, the first terminal device may determine whether SL RLF occurs between the first terminal device and the second terminal device according to the feedback reception condition. Here, determining whether SL RLF occurs between the first terminal device and the second terminal device according to the feedback reception condition may be understood as: a fifth number (or fifth number may also be understood as a counter) is maintained for each carrier group included in a PC5-RRC connection, the fifth number being initialized to 0. Once the PC5-RRC connection is established or the fifth threshold is (re) configured, the fifth number is (re) initialized to 0.

Further, for each feedback reception opportunity of the first carrier group data transmitted on the first carrier group, processing each feedback reception opportunity of the first carrier group data according to a sequence in a time domain, and when a fifth number of feedback for the first carrier group data which is not continuously received on the first carrier group is smaller than a fifth threshold value and feedback for the first carrier group data is received on a next feedback reception opportunity of the first carrier group data, setting the fifth number to 0; when the fifth number of consecutive non-receipt of feedback for the first carrier group data on the first carrier group is smaller than the fifth threshold value and the feedback for the first carrier group data is not received on the next feedback reception occasion of the first carrier group data, the fifth number is added by 1. And so on, determining that SL RLF occurs on the first carrier group between the first terminal device and the second terminal device until a fifth number of consecutive non-received feedback for the first carrier group data is greater than or equal to a fifth threshold.

The fifth threshold may be configured by the network device (base station) or pre-configured (pre-configuration), without limitation. It should be noted that, in the embodiment of the present application, the fifth threshold may be configured for each of different carrier wave groups. It should be noted that the first threshold, the second threshold, the third threshold, the fourth threshold and the fifth threshold may be different from each other; alternatively, the first threshold, the second threshold, the third threshold, the fourth threshold, and the fifth threshold may be partially or completely the same, and the present application is not limited thereto.

For example, please refer to fig. 7b, fig. 7b is another schematic diagram of a scenario for determining SL RLF according to an embodiment of the present application. As shown in fig. 7b, one PC5-RRC connection may send data on carrier 1, carrier 2, carrier 3 and carrier 4, specifically, data 1 on carrier 1, data 2 on carrier 2, data 3 on carrier 3 and data 4 on carrier 4, where data 1 sent on carrier 1 at different times may be the same data, may also be different data, data 2 sent on carrier 2 at different times may be the same data, may also be different data, data 3 sent on carrier 3 at different times may be the same data, may also be different data, and data 4 sent on carrier 4 at different times may be the same data, may also be different data, where no limitation is made. In fig. 7b, the feedback of data 1 is mainly transmitted on carrier 1, the feedback of data 2 is transmitted on carrier 2, the feedback of data 3 is transmitted on carrier 2, and the feedback of data 4 is transmitted on carrier 4, which is an example. Wherein, a variable k may be maintained for carrier group 1 consisting of carrier 1 and carrier 2, and a variable l may be maintained for carrier group 2 consisting of carrier 3 and carrier 4, with variable k and variable l initialized to 0. Wherein the variable k and the variable l can be understood as a fifth number. That is, the feedback condition statistics may be performed by dividing the carrier 1 and the carrier 2 into the carrier group 1, and dividing the carrier 3 and the carrier 4 into the carrier group 2. Assume that the fifth threshold is 3. Wherein:

1. The statistical process of the feedback receiving time corresponding to the data sent on the carrier group 1 is as follows:

when PSFCH reception exists on PSFCH reception time 1 corresponding to the data 1, initializing a variable k to 0;

if PSFCH reception does not exist at PSFCH reception time 1 corresponding to data 2, adding 1 to variable k, wherein variable k is equal to 1;

when PSFCH reception exists on PSFCH reception time 2 corresponding to the data 1, the variable k is reinitialized to 0;

if PSFCH reception does not exist at PSFCH reception time 3 corresponding to the data 2, adding 1 to the variable k, wherein the variable k is equal to 1;

if PSFCH reception does not exist at PSFCH reception time 3 corresponding to the data 1, adding 1 to the variable k, wherein the variable k is equal to 2;

and if PSFCH receiving does not exist on the PSFCH receiving time 4 corresponding to the data 1, adding 1 to the variable k, wherein the variable k is equal to 3.

At this time, the variable k (i.e., the variable k=3) reaches the fifth threshold, it is determined that SL RLF occurs on the carrier group 1 between the first terminal device and the second terminal device.

The statistical process of the feedback receiving time corresponding to the data sent on the carrier group 2 is as follows:

when PSFCH reception exists on PSFCH reception time 1 corresponding to data 3, initializing a variable l to 0;

if PSFCH reception does not exist on PSFCH reception opportunity 1 corresponding to data 4, the variable l is reinitialized to 0;

When PSFCH reception exists on PSFCH reception time 2 corresponding to data 3, the variable l is reinitialized to 0;

if PSFCH reception does not exist at PSFCH reception time 2 corresponding to the data 4, adding 1 to the variable l, wherein the variable l is equal to 1;

when PSFCH reception exists at PSFCH reception time 3 corresponding to data 4, the variable l is reinitialized to 0;

and if PSFCH receiving does not exist at the PSFCH receiving time 3 corresponding to the data 3, adding 1 to the variable l, wherein the variable l is equal to 1.

At this time, the variable l (i.e., the variable l=1) does not reach the fifth threshold, it is determined that SL RLF does not occur on the carrier group 2 between the first terminal device and the second terminal device. Here, the fact that no SL RLF occurs on carrier group 2 between the first terminal device and the second terminal device may also be cleaved that the continuous HARQ DTX of the second terminal device on carrier group 2 does not reach the maximum number of times.

In general, one carrier may correspond to one sidelink HARQ entity. For example, carrier 1 corresponds to sidelink HARQ entity 1, carrier 2 corresponds to sidelink HARQ entity 2, carrier 3 corresponds to sidelink HARQ entity 3, and carrier 4 corresponds to sidelink HARQ entity 4. In implementation (4), the logic body for performing the increment or (re) initialization on the variable k on a certain carrier group should be a sidelink HARQ entity corresponding to any carrier in the carrier group. For example, assuming that carrier 1 and carrier 2 form carrier group 1 and carrier 3 and carrier 4 form carrier group 2, the logic body for counting the feedback reception situation of carrier group 1 may be a sidelink HARQ entity 1 or a sidelink HARQ entity 2; the logical body for counting the feedback reception situation of the carrier group 2 may be the sidelink HARQ entity 3 or the sidelink HARQ entity 4.

Alternatively, in some embodiments, when the first terminal device cannot determine which carrier specifically has the SL RLF, but only determines that the SL RLF has occurred on the PC5-RRC connection, the first terminal device releases the PC5-RRC connection, where releasing the PC5-RRC connection may be understood as releasing the data radio bearer (data radio bearer, DRB) and signaling radio bearer (signaling radio bearer, SRB) of the second terminal device, discarding the NR side-link communication related configuration of the second terminal device, resetting the side-link specific MAC of the second terminal device, and indicating to the upper layer that the PC5-RRC connection of the second terminal device is released (i.e., PC5 is not available). That is, when the first terminal device cannot determine which carrier specifically has the continuous HARQ DTX up to the maximum number of times, and cannot determine which carrier specifically has the RLC entity re-transmission up to the maximum number of times, the first terminal device can only determine that the SL RLF has occurred on the PC5-RRC connection, and the first terminal device releases the PC5-RRC connection, releases the data radio bearer and the signaling radio bearer of the second terminal device, discards the NR side-link communication related configuration of the second terminal device, resets the side-link specific MAC of the second terminal device, and indicates to the upper layer that the PC5-RRC connection of the second terminal device is released (i.e., PC5 is unavailable).

Alternatively, in some embodiments, when the first terminal device may determine that the first carrier of the SL RLF has occurred, the first terminal device may delete or release the first carrier. Wherein, the deletion and/or release of the first carrier by the first terminal device may be understood as at least one of the following: the first terminal device deletes the first carrier from the carrier used by the first terminal device to send data to the second terminal device, the first terminal device deletes the first carrier from the carrier used by the first terminal device to receive the data sent by the second terminal device, the first terminal device clears the SL grant (grant) allocated to the second terminal device on the first carrier, and the first terminal device refreshes the HARQ buffer area associated with the first carrier of the second terminal device.

In the embodiment of the present application, the first terminal device may determine that the first carrier in which the SL RLF occurs may also be understood that the first terminal device may determine that the first carrier in which the continuous HARQ DTX occurs up to the maximum number of times, or the first terminal device may determine that the first carrier in which the RLC entity retransmits up to the maximum number of times.

Alternatively, in one embodiment, when SL RLF occurs for each of all carriers that the first terminal device transmits data to the second terminal device, SL RLF is considered to occur between the first terminal device and the second terminal device.

Alternatively, in one embodiment, when no SL RLF occurs on a portion of the carrier on which the first terminal device transmits data to the second terminal device, it is considered that no SL RLF occurs between the first terminal device and the second terminal device.

Optionally, in some embodiments, when the first terminal device determines that the first carrier of the SL RLF occurs, the first terminal device may further send first indication information to the second terminal device, and accordingly, the second terminal device receives the first indication information from the first terminal device. The first indication information is used for indicating that the SL RLF occurs on the first carrier, or the first indication information is used for indicating that the first carrier is deleted or released. That is, the second terminal device may delete or release the first carrier based on the first indication information. The second terminal device deletes or releases the first carrier may be understood as deleting the first carrier from a carrier used by the second terminal device to receive data from the first terminal device by the second terminal device, and/or deleting the first carrier from a carrier used by the second terminal device to send feedback to the first terminal device by the second terminal device, and/or clearing an SL grant (grant) allocated to the first terminal device on the first carrier by the second terminal device, and/or refreshing an HARQ buffer associated with the first carrier of the first terminal device by the second terminal device.

Optionally, in some embodiments, if the first terminal device is in an RRC connected state, i.e. if an RRC connection exists between the first terminal device and the access network device (e.g. a base station), the first terminal device may further send second indication information to the access network device, the second indication information being used to indicate the first carrier on which SL RLF occurs. The implementation manner of the second indication information for indicating the first carrier wave generating the SL RLF specifically includes: 1. the second indication information may directly include carrier information of the first carrier on which the SL RLF occurs, for example, may be an identification of the first carrier, or an index of the first carrier, or information such as a frequency point of the first carrier, which is not limited herein. Therefore, the access network device can determine the first carrier on which the SL RLF has occurred from the carrier information of the first carrier included in the second indication information by receiving the second indication information from the first terminal device. Alternatively, the second indication information may also include carrier information of carriers available when the first terminal device currently transmits data to the second terminal device, so the access network device determines that the available carriers do not include the first carrier by receiving the second indication information from the first terminal device. The access network device may also determine that the first carrier of the SL RLF has occurred by receiving the second indication information from the first terminal device, and combining carrier information of carriers available when the first terminal device sends data to the second terminal device included in the second indication information received by the access network device last time. For example, it is assumed that the second indication information received by the access network device last time includes carrier 1, carrier 2 and carrier 3, and the second indication information received by the access network device last time includes carrier 1 and carrier 2, so the access network device may determine that carrier 3 is the carrier on which SL RLF occurs.

Alternatively, in some embodiments, the first terminal device may send, in addition to the second indication information to the access network device, information of the second terminal device, for example, a Layer 2 identifier (i.e. Layer-2 ID) of the second terminal device, etc., which is not limited herein.

It should be noted that the second indication information and/or the information of the second terminal device may be carried in a sideline UE information new radio message (sideline UE information nr message) in 3gpp TS 38.331, which is not limited herein.

It should be noted that, after the access network device receives the second indication information and/or the information of the second terminal device, the access network device may send third indication information to the first access network device, where the third indication information is used to instruct the first terminal device to delete or release the first carrier where the SL RLF occurs. Therefore, the deletion or release of the first carrier by the first terminal device may be understood as: and the first terminal equipment responds to the third indication information, and deletes or releases the first carrier.

Optionally, in some embodiments, after the first terminal device deletes or releases the first carrier, the access network device does not schedule the first terminal device to send data to the second terminal device using the first carrier.

In the embodiment of the application, when the transmission of one PC5-RRC connection is performed on a plurality of carriers, PSFCH receiving occasions related to the transmission of each PSSCH/MAC PDU on each carrier can be counted together, and further whether SL RLF occurs on the PC5-RRC connection can be determined. Alternatively, when the transmission of one PC5-RRC connection is performed on multiple carriers, PSFCH reception opportunities related to PSSCH/MAC PDU transmission on different carriers may be counted separately, so as to determine whether SL RLF occurs on a specific carrier on the PC5-RRC connection. That is, the embodiment of the present application can determine whether SL RLF occurs when transmission of one PC5-RRC connection is performed on a plurality of carriers.

Further, when the first terminal device determines that the SL RLF occurs on the first carrier, the first terminal device may be configured to inform the second terminal device to delete or release the first carrier on which the SL RLF occurs by sending the first indication information to the second terminal device, so that unnecessary communication interruption caused by directly releasing the PC5-RRC connection when the SL RLF is found in the related art is reduced. That is, the embodiment of the application can determine the first carrier wave with the specific SL RLF, and only delete or release the first carrier wave when determining the first carrier wave with the specific SL RLF, while other carrier waves without the specific SL RLF can still be used for normal communication between the first terminal device and the second terminal device, thereby improving the reliability of communication.

Referring to fig. 8, fig. 8 is another flow chart of the communication method according to the embodiment of the application. The method may be performed by the first terminal device or may also be performed by a chip in the first terminal device, hereinafter collectively referred to as the first terminal device for convenience of description. The method shown in fig. 8 may include the following operations.

S801, the first terminal device determines that a side-uplink SL radio link failure RLF occurs on the first carrier.

In some embodiments, the first terminal device determines that a side-uplink SL radio link failure RLF occurred on the first carrier. Wherein the first carrier is any one or more of a plurality of carriers for the first terminal device to transmit data to the second terminal device.

Specifically, the above-mentioned first terminal device determining that SL RLF occurs on the first carrier may be understood as: if the first terminal device determines that the number of retransmissions of the data reaches the maximum number of retransmissions based on the first radio link control (radio link control, RLC) entity, determining that a SL RLF occurs for a first carrier associated with the first RLC entity, where the first RLC entity is configured to send the data to the second terminal device. It should be noted that the data transmitted by the first RLC entity may also be described as RLC service data units (service data unit, SDU). That is, when the first RLC entity of the first terminal apparatus determines that the RLC sdu transmitted to the second RLC entity of the second terminal apparatus reaches the maximum number of retransmissions, it means that the first RLC entity causes/occurs SL RLF or is described as meaning that the carrier associated with the first RLC entity (i.e., the first carrier) causes/occurs SL RLF. It should be noted that the number of first carriers associated with the first RLC entity may be 1 or more.

Further, the above determination of the first carrier occurrence SL RLF associated with the first RLC entity may be understood as: if the first terminal device determines, based on the first radio link control RLC entity, that the number of retransmissions of the data reaches the maximum number of retransmissions and the first RLC entity is an RLC entity corresponding to a packet data convergence protocol (packet data convergence protocol, PDCP) entity using packet duplication, then determining that a SL RLF occurs for a first carrier associated with the first RLC entity. It should be noted that, in the packet duplication scenario, since the transmission of the first RLC entity may be mapped onto one carrier set (which may also be understood as that the transmission of the first RLC entity is mapped onto the carrier set corresponding to the logical channel corresponding to the first RLC entity), one carrier set includes 1 or more carriers. Accordingly, the first terminal device may determine 1 or more carriers included in the carrier set associated with the first RLC entity as the first carrier, i.e., 1 or more carriers in which SL RLF has occurred.

It should be noted that, in a scenario where the first carrier includes a plurality of carriers, or where the first carrier associated with the first RLC entity is understood to include a plurality of carriers, or where the carrier set associated with the first RLC entity includes a plurality of carriers, after determining that the first carrier (or understood to be the first carrier associated with the first RLC entity, or understood to be the carrier set associated with the first RLC entity) has SL RLF, the first terminal device may further send, on each carrier in the first carrier, first information to the second terminal device, where the first information is used to trigger the second terminal device to feed back the second information; if the first terminal device does not receive the second information sent by the second terminal device on the second carrier, or the first terminal device does not receive the second information sent by the second terminal device on the second carrier within a preset time after sending the first information, the first terminal device determines that SL RLF occurs on the second carrier, where the second carrier is any one of the first carriers. The first information may be information triggering feedback of channel state information (channel state information, CSI), or the first information may also be media access control unit (medium access control control element, MAC CE), etc., which is not limited herein. Accordingly, the second information may be CSI report, or the second information may also be MAC CE, etc., which is not limited herein. That is, in a scenario where it is determined that SL RLF has occurred or in a scenario where it is determined that SL RLF has occurred on a plurality of carriers, the first information and the second information may be further used to determine in particular which carrier or carriers caused SL RLF.

It should be noted that, if it can be specifically determined from the first carriers which one or more carriers (i.e., the second carrier) have the SL RLF, when the release of the carriers is indicated later, it may be indicated which one or more carriers (i.e., the second carrier) in the first carriers specifically need to be released, so that it may be avoided that the carriers in the first carriers where the SL RLF does not occur are released.

S802, the first terminal equipment sends first indication information to the second terminal equipment.

In some embodiments, the first terminal device sends the first indication information to the second terminal device, and accordingly, the second terminal device receives the first indication information from the first terminal device. The first indication information is used for indicating that the SL RLF occurs on the first carrier, or the first indication information is used for indicating that the first carrier is deleted or released. That is, the second terminal device may delete or release the first carrier based on the first indication information. Wherein, deleting or releasing the first carrier by the second terminal device may be understood as at least one of the following: the second terminal device deletes the first carrier from the carrier used by the second terminal device to receive the data from the first terminal device, the second terminal device deletes the first carrier from the carrier used by the second terminal device to send feedback to the first terminal device, the second terminal device clears the SL grant (grant) allocated to the first terminal device on the first carrier, and the second terminal device flushes the HARQ buffer associated with the first carrier of the first terminal device.

Optionally, in some embodiments, when the first terminal device determines that the first carrier of the SL RLF occurs, the first terminal device may further delete or release the first carrier. Wherein, the deletion and/or release of the first carrier by the first terminal device may be understood as at least one of the following: the first terminal device deletes the first carrier from the carrier used by the first terminal device to send data to the second terminal device, the first terminal device deletes the first carrier from the carrier used by the first terminal device to receive feedback from the second terminal device, the first terminal device clears the SL grant (grant) allocated to the second terminal device on the first carrier, and the first terminal device flushes the HARQ buffer associated with the first carrier of the second terminal device.

Optionally, in some embodiments, when the first carrier includes a plurality of carriers, if the plurality of carriers included in the first carrier are all carriers corresponding to one RLC bearer, the first terminal apparatus may suspend transmission on the RLC entity and the corresponding logical channel included in the RLC bearer; or releasing the RLC entity and corresponding logical channel included in the RLC bearer; alternatively, the logical channel corresponding to the RLC bearer is mapped to other carriers (or other new carrier (s)), and the RLC entity and corresponding logical channel included in the RLC bearer are reconstructed.

It should be noted that one new carrier of the other one or more new carriers may be a carrier mapped by another RLC entity that originally corresponds to the same PDCP entity, and the other RLC entity is not mapped to the new carrier. For example, if another RLC entity originally mapped carrier has carrier 1 and carrier 2, then that RLC entity is now mapped to carrier 1 and the other RLC entity is no longer mapped to carrier 1. One new carrier of the one or more new carriers may be a carrier other than a carrier mapped by another RLC entity corresponding to the same PDCP entity, which is not limited herein.

Optionally, in some embodiments, if the first terminal device is in an RRC connected state and the multiple carriers included in the first carrier are all carriers corresponding to one RLC bearer, the first terminal device may further send fourth indication information to the access network device. The fourth indication information may be used to indicate RLC bearer information, for example, the fourth indication information may include RLC bearer configuration index, etc., which is not limited herein. Alternatively, the fourth indication information may be used to indicate information of RLC configuration, or the fourth indication information may be used to indicate information of a logical channel, etc., without limitation. Therefore, the access network device receives the fourth indication information from the first terminal device, and can determine, according to the RLC bearer information or RLC configuration information or the logical channel information included in the fourth indication information, that all carriers corresponding to the RLC bearer or the logical channel are the first carriers in which SL RLF occurs.

Optionally, in some embodiments, the first terminal device may send, in addition to the fourth indication information to the access network device, information of the second terminal device, for example, a Layer 2 identifier (i.e. Layer-2 ID) of the second terminal device, which is not limited herein.

It should be noted that, the fourth indication information and/or the information of the second terminal device may be carried in a sidelink information nr message, which is not limited herein.

It should be noted that, after the access network device receives the fourth indication information and/or the information of the second terminal device, the access network device may further send fifth indication information to the first access network device, where the fifth indication information is used to instruct the first terminal device to suspend transmission on the RLC entity and the corresponding logical channel included in the RLC bearer; or, the fifth indication information is used for indicating the first terminal equipment to release the RLC entity and the corresponding logical channel included in the RLC bearer; or, the fifth indication information is used to instruct the first terminal device to map the logical channel corresponding to the RLC bearer to other carriers, and reconstruct the RLC entity and the corresponding logical channel included in the RLC bearer. Therefore, the first terminal device may suspend transmission on the RLC entity and the corresponding logical channel included in the RLC bearer; or releasing the RLC entity and corresponding logical channel included in the RLC bearer; alternatively, mapping the logical channel corresponding to the RLC bearer to another carrier, and reconstructing the RLC entity and the corresponding logical channel included in the RLC bearer may be understood as: the first terminal equipment suspends transmission on an RLC entity and a corresponding logical channel included in the RLC bearer in response to the fifth indication information; or, the first terminal device responds to the fifth indication information to release the RLC entity and the corresponding logical channel included in the RLC bearer; or, the first terminal device maps the logical channel corresponding to the RLC bearer to other carriers in response to the fifth indication information, and reconstructs the RLC entity and the corresponding logical channel included in the RLC bearer.

Optionally, the access network device may further send information for indicating that the reconfiguration packets are copied to the first terminal device, and/or the access network device may further send information for indicating that the two carrier sets are configured to the first terminal device.

Optionally, the first terminal device may further send sixth indication information to the second terminal device, and accordingly, the second terminal device receives the sixth indication information from the first terminal device. The sixth indication information is used to indicate information of RLC bearers/RLC configurations/logical channels causing SL RLF. And the second terminal equipment receives the sixth indication information and can delete/release the carrier corresponding to the RLC bearing/RLC configuration/logic channel indicated by the sixth indication information. The RLC bearer/RLC configuration/logical channel to carrier correspondence/mapping may be acquired by the second terminal device before this. For example, the first terminal device configures RLC bearers/RLC configurations/logical channels to the second terminal device with a correspondence/mapping to carriers.

Optionally, the first terminal device may further send seventh indication information to the second terminal device, and accordingly, the second terminal device receives the seventh indication information from the first terminal device. The seventh indication information is used for indicating the corresponding relation/mapping between the configuration/modification/updating RLC bearer/RLC configuration/logical channel and carrier. The RLC bearer/RLC configuration/logical channel is the RLC that causes/generates SL RLF. The RLC bearer/RLC configuration/logical channel includes an RLC that causes/generates SL RLF, and another RLC of the same PDCP entity corresponding to the RLC that causes/generates SL RLF.

Optionally, the first terminal device may also delete/release RLC bearers/RLC configurations/logical channels that cause/occur SL RLF. Optionally, the first terminal device may further send eighth indication information to the second terminal device, and accordingly, the second terminal device receives the eighth indication information from the first terminal device. The eighth indication information is used for indicating to configure/modify/update RLC bearers/RLC configuration/logical channels corresponding to PDCP entity/side-chain radio bearer SLRBs and/or delete/release RLC bearers/RLC configuration/logical channels causing/occurring SL RLF.

Optionally, in some embodiments, packet duplication is not used for PDCP for RLC bearers that cause/occur SL RLF.

In an embodiment of the application, when the transmission of one PC5-RRC connection is made on multiple carriers, the first terminal device is able to determine which carrier or carriers (i.e. the first carrier) in particular caused the SL RLF. And when the SL RLF is determined to be caused by the first carrier, the PC5-RRC connection is not released, but only the first carrier is deleted or released, and other carriers which do not generate the SL RLF can still be used for normal communication between the first terminal equipment and the second terminal equipment, so that unnecessary communication relay caused by detecting the SL RLF is reduced, and the reliability of communication is improved.

The communication device provided by the present application will be described in detail with reference to fig. 9 to 10.

Referring to fig. 9, fig. 9 is a schematic structural diagram of a communication device according to an embodiment of the application. The communication device shown in fig. 9 may be used to perform part or all of the functions of the terminal device in the method embodiments described above with reference to fig. 2-8. The device can be a terminal device, a device in the terminal device, or a device which can be matched with the terminal device for use. The communication device may also be a chip system. The communication apparatus shown in fig. 9 may include a transceiving unit 901 and a processing unit 902. The processing unit 902 is configured to perform data processing. The transceiver unit 901 is integrated with a receiving unit and a transmitting unit. The transceiving unit 901 may also be referred to as a communication unit. Alternatively, the transceiver unit 901 may be split into a receiving unit and a transmitting unit. The following processing unit 902 and the transceiver unit 901 are the same, and will not be described in detail. Wherein:

in a first implementation:

a transceiving unit 901 for transmitting data to the second terminal device over a plurality of carriers over the side uplink SL;

a processing unit 902, configured to determine a feedback reception situation for the data on feedback reception occasions on the multiple carriers, where the feedback reception occasions are reception occasions for feedback of the data;

The processing unit 902 is configured to determine whether an RLF occurs between the first terminal device and the second terminal device according to the feedback reception condition.

In one possible implementation, the processing unit 902 is configured to:

In one possible implementation, after the processing unit 902 determines whether feedback for the data is received on each feedback reception occasion on each of the plurality of carriers in turn, the processing unit 902 is further configured to:

In one possible implementation, the processing unit 902 is configured to:

In one possible implementation, the transceiver unit 901 is further configured to:

In a possible implementation, the processing unit 902 is further configured to:

deleting or releasing the first carrier.

In a second implementation:

a processing unit 902, configured to determine that a side uplink SL radio link failure RLF occurs on a first carrier, where the first carrier is any one or more of multiple carriers used by the first terminal device to send data to a second terminal device;

the transceiver 901 is configured to send first indication information to the second terminal device, where the first indication information is used to indicate the first carrier, or the first indication information is used to indicate deletion or release of the first carrier.

In one possible implementation, the processing unit 902 is configured to:

In one possible implementation, the first carrier includes a plurality of carriers; based on the processing unit 902 determining that SL RLF occurs on the first carrier, the processing unit 902 is further configured to:

In a possible implementation, the processing unit 902 is further configured to:

deleting or releasing the first carrier.

Other possible implementation manners of the communication apparatus may be referred to the description of the functions of the terminal device in the method embodiments corresponding to fig. 2 to 8, which are not repeated herein.

Referring to fig. 10, fig. 10 is a schematic structural diagram of another communication device according to an embodiment of the present application. As shown in fig. 10, the communication device may be a terminal device (for example, a first terminal device or a second terminal device) described in the embodiment of the present application, and is configured to implement the functions of the terminal device in fig. 2 to 8. For ease of illustration, fig. 10 shows only the main components of terminal device 1000. As shown in fig. 10, the terminal device 1000 includes a processor, a memory, a control circuit, an antenna, and an input-output device. The processor is mainly used for processing communication protocols and communication data, controlling the whole terminal device 1000, executing software programs and processing data of the software programs. The memory is mainly used for storing software programs and data. The control circuit is mainly used for converting baseband signals and radio frequency signals and processing the radio frequency signals. The antenna is mainly used for receiving and transmitting radio frequency signals in the form of electromagnetic waves. Input and output devices such as touch screens, display screens, microphones, keyboards, etc. are mainly used for receiving data input by a user and outputting data to the user.

Taking terminal device 1000 as a mobile phone for example, when terminal device 1000 is turned on, the processor may read the software program in the storage unit, interpret and execute the instructions of the software program, and process the data of the software program. When data is required to be transmitted wirelessly, the processor carries out baseband processing on the data to be transmitted and then outputs a baseband signal to the control circuit, and the control circuit carries out radio frequency processing on the baseband signal and then transmits the radio frequency signal outwards in the form of electromagnetic waves through the antenna. When data is transmitted to the terminal device 1000, the control circuit receives a radio frequency signal through the antenna, converts the radio frequency signal into a baseband signal, and outputs the baseband signal to the processor, which converts the baseband signal into data and processes the data.

Those skilled in the art will appreciate that for ease of illustration, only one memory and processor is shown in fig. 10. In some embodiments, terminal device 1000 can include multiple processors and memory. The memory may also be referred to as a storage medium or storage device, etc., and embodiments of the present invention are not limited in this respect.

As an alternative implementation, the processor may include a baseband processor, which is mainly used to process the communication protocol and the communication data, and a central processor, which is mainly used to control the entire terminal device 1000, execute a software program, and process the data of the software program. The processor in fig. 10 integrates the functions of a baseband processor and a central processing unit, and those skilled in the art will appreciate that the baseband processor and the central processing unit may be separate processors, interconnected by bus technology, etc. Terminal device 1000 can include multiple baseband processors to accommodate different network formats, terminal device 1000 can include multiple central processors to enhance its processing capabilities, and various components of terminal device 1000 can be coupled via various buses. The baseband processor may also be expressed as a baseband processing circuit or a baseband processing chip. The central processing unit may also be expressed as a central processing circuit or a central processing chip. The function of processing the communication protocol and the communication data may be built in the processor, or may be stored in the storage unit in the form of a software program, which is executed by the processor to realize the baseband processing function.

In one example, the antenna and control circuit with the transceiving function may be regarded as the transceiving unit 1010 of the terminal device 1000, and the processor with the processing function may be regarded as the processing unit 1020 of the terminal device 1000. As shown in fig. 10, the terminal device 1000 includes a transceiving unit 1010 and a processing unit 1020. The transceiver unit may also be referred to as a transceiver, transceiver device, etc. Alternatively, a device for implementing a receiving function in the transceiver unit 1010 may be regarded as a receiving unit, and a device for implementing a transmitting function in the transceiver unit 1010 may be regarded as a transmitting unit, i.e., the transceiver unit 1010 includes a receiving unit and a transmitting unit. For example, the receiving unit may also be referred to as a receiver, a receiving circuit, etc., and the transmitting unit may be referred to as a transmitter, a transmitting circuit, etc.

The embodiment of the application also provides a computer readable storage medium, wherein instructions are stored in the computer readable storage medium, and when the computer readable storage medium runs on a processor, the method flow of the embodiment of the method is realized.

The present application also provides a computer program product, which when run on a processor, implements the method flows of the method embodiments described above.

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

In the several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, and for example, the division of the units is merely a logical functional division, and units illustrated as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed over multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application may be embodied essentially or in a part contributing to the prior art or in a part of the technical solution, in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present application. The foregoing computer-readable storage media can be any available media that can be accessed by a computer. Taking this as an example but not limited to: the computer readable medium may include random access memory (random access memory, RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (electrically erasable programmable read only memory, EEPROM), compact disc read-only memory (compact disc read-only memory, CD-ROM), universal serial bus flash disk (universal serial bus flash disk), a removable hard disk, or other optical disk storage, magnetic disk storage media, or other magnetic storage device, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. In addition, by way of example and not limitation, many forms of RAM are available, such as Static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous DRAM (SLDRAM), or direct memory bus RAM (DR RAM).

The foregoing is merely a specific implementation of the present application, but the scope of the embodiments of the present application is not limited thereto, and any person skilled in the art may easily think about changes or substitutions within the technical scope of the embodiments of the present application, and all changes and substitutions are included in the scope of the embodiments of the present application. Therefore, the protection scope of the embodiments of the present application shall be subject to the protection scope of the claims.

Claims

1. A communication method, characterized in that the method is applied to a first terminal device, comprising:

2. The method of claim 1, wherein the determining feedback reception for the data on the feedback reception occasions on the plurality of carriers comprises:

The determining whether SLRLF occurs between the first terminal device and the second terminal device according to the feedback receiving condition includes:

3. The method of claim 2, wherein after the sequentially determining whether feedback for the data is received on each feedback reception occasion on each of the plurality of carriers, the method further comprises:

4. The method of claim 1, wherein the determining feedback reception for the data on the feedback reception occasions on the plurality of carriers comprises:

5. The method of claim 4, wherein after determining whether feedback for the data is received on each feedback reception occasion on the first carrier in turn, the method further comprises:

6. The method of claim 1, wherein the determining feedback reception for the data on the feedback reception occasions on the plurality of carriers comprises:

7. The method of claim 6, wherein the sequentially determining whether feedback for the first data is received on each feedback reception occasion of the first data transmitted on the first carrier further comprises:

8. The method according to any one of claims 4-7, further comprising:

9. The method according to any one of claims 4-8, further comprising:

deleting or releasing the first carrier.

10. The method according to any one of claims 4-9, further comprising:

11. A communication method, characterized in that the method is applied to a first terminal device, comprising:

12. The method of claim 11, wherein the determining that SL RLF occurs on the first carrier comprises:

13. The method of claim 12, wherein the determining that the first carrier associated with the first RLC entity is SL RLF comprises:

14. The method of any of claims 11-13, wherein the first carrier comprises a plurality of carriers; after the determining that SL RLF occurs on the first carrier, the method further comprises:

15. The method according to any one of claims 11-14, further comprising:

deleting or releasing the first carrier.

16. The method according to any one of claims 11-15, further comprising:

17. A communication device comprising means or modules for performing the method of any of claims 1-10 or means or modules for performing the method of any of claims 11-16.

18. A communication device comprising a processor and a communication interface for receiving signals from other communication devices than the communication device and transmitting to the processor or sending signals from the processor to other communication devices than the communication device, the processor being configured to cause the communication device to implement the method of any of claims 1-10 or 11-16 by logic circuitry or execution of code instructions.

19. A computer readable storage medium, characterized in that the storage medium has stored therein a computer program or instructions which, when executed by a computer, implement the method of any of claims 1-10 or 11-16.

20. A computer program product comprising computer program code for implementing the method of any of claims 1-10 or 11-16 when said computer program code is run on a computer.