COMMUNICATION METHOD, DEVICE, AND SYSTEM

Abstract

Embodiments of the present application provide a communication method, apparatus, and system for avoiding false triggering of a radio link failure RLF or reducing the possibility of false triggering of RLF. The method includes: a first user equipment transmitting first data to a second user equipment via a sidelink SL; if the first user equipment does not receive first feedback information, the first user equipment initializing a first counter or leaving a count value of the first counter unchanged, where the first feedback information indicates whether the second user equipment has successfully received the first data, and the first counter is used for RLF detection.

Description

[Technical Field]

[0002] The present application relates to the field of sidelink (SL) communication technologies, and in particular to SL communication methods, devices, and systems. [Background technology]

[0003] Vehicle-to-everything (V2X) is a key technology for intelligent transportation systems and is considered one of the fields with the greatest industrial potential and clearest market demand in the Internet of Things system. Vehicle-to-everything typically provides vehicle information by using sensors and in-vehicle terminals installed in vehicles to implement vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), vehicle-to-network (V2N), and vehicle-to-pedestrian (V2P) communications.

[0004] V2X features a wide application space, great industrial potential, and high social benefits. It is of great significance for promoting innovation and development in the automotive and information and communications industries, building new models and forms of automotive and transportation services, promoting technological innovation and application including driverless driving, assisted driving, intelligent driving, connected driving, intelligent connected driving, autonomous driving, and car sharing, and improving transportation efficiency and safety.

[0005] Typically, in a V2X scenario, a communication link for direct communication between a terminal and another terminal is sometimes called a sidelink (SL).

[0006] Currently, new radio (NR) V2X supports hybrid automatic repeat request (HARQ) feedback over SL for unicast and multicast, and HARQ feedback is transmitted over the physical sidelink feedback channel (PSFCH). Also, for unicast, SL radio link failure (RLF) can be detected based on HARQ. Specifically, PSFCH If the number of consecutive failures to receive a signal reaches a certain threshold, a SL RLF is triggered. However, in the prior art, the transmitting end may falsely trigger a RLF. [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] 3GPP TS 38.213: “NR; Physical Layer Procedures for Control” [Non-patent document 2] 3GPP TS 38.321: “NR; Medium Access Control (MAC) Protocol Specification” Summary of the Invention

[0008] SUMMARY OF THE INVENTION Embodiments of the present application provide communication methods, devices, and systems for avoiding false triggering of RLF or reducing the likelihood of false triggering of RLF.

[0009] To achieve the above objectives, the following technical solutions are used in the embodiments of this application:

[0010] According to a first aspect, a communication method is provided. A communication device performing the communication method may be a first user equipment (UE) or a module used in the first user equipment, such as a chip or a chip system. The following provides an example in which the method is performed by the first user equipment. The first user equipment transmits first data to a second user equipment (UE) via a side link (SL). If the first user equipment does not receive first feedback information, the first user equipment initializes a first counter or leaves the count value of the first counter unchanged. The first feedback information indicates whether the second user equipment has successfully received the first data. The first counter is used for radio link failure (RLF) detection. In the communication method provided in this embodiment of the present application, the first feedback information is not received by the first user equipment because the first user equipment does not receive the first feedback information, not because there is a problem with the radio link. The first counter used for RLF detection does not count cases where the first feedback information is not received because the first user equipment does not receive the first feedback information, and therefore the count value of the first counter does not erroneously / prematurely / fastly reach the count value for triggering RLF, thereby avoiding erroneous triggering of RLF, reducing communication delay, and improving / ensuring communication quality or reliability.

[0011] According to the first aspect, in a possible implementation, when a first user equipment receives first feedback information and fails to receive the first feedback information, the first user equipment increments a count value of a first counter by 1. In the above method, the first user equipment receiving but failing to receive the first feedback information may be the first user equipment failing to receive the first feedback information due to a problem with the radio link. The first counter counts the cases in which the first user equipment receives but fails to receive the first feedback information. Compared to the prior art, this method imposes a constraint on the increase of the count value of the first counter, so that the count value of the first counter does not erroneously / prematurely / too quickly reach the count value for triggering RLF. This avoids erroneous triggering of RLF, reduces communication delay, and improves / guarantees communication quality or reliability.

[0012] According to the first aspect, in a possible implementation, the first user equipment not receiving the first feedback information includes the first user equipment not receiving the first feedback information if the reception of the first feedback information conflicts with the first transmission. In the above method, the first counter used for RLF detection does not count resource contention cases, so that the first counter can exclude other reasons that may cause the first user equipment not to receive the first feedback information. The first counter counts as many times as possible the number of times the first user equipment fails to receive the first feedback information due to problems with the radio link as a target target, so that the count value of the first counter does not erroneously / prematurely / too quickly reach the count value for triggering RLF. This avoids false triggering of RLF, reduces communication delay, and improves / guarantees communication quality or reliability.

[0013] According to the first aspect, in a possible implementation, when reception of the first feedback information conflicts with the first transmission, not receiving the first feedback information by the first user equipment includes receiving the first feedback information conflicting with the first transmission and having a priority equal to or lower than the priority of the first transmission. In the above method, when resource contention occurs and reception of the first feedback information has a low priority, the first feedback information is not received, not because there is a problem with the radio link, but because the first user equipment performs the first transmission with a higher priority but does not receive the first feedback information. The first counter used for RLF detection does not count cases where the first feedback information is not received because the first user equipment does not receive the first feedback information, and therefore the count value of the first counter does not erroneously / prematurely / fastly reach the count value for triggering RLF. This avoids false triggering of RLF, reduces communication delay, and improves / guarantees communication quality or reliability.

[0014] According to the first aspect, in a possible implementation, the first user equipment initializing the first counter includes the first user equipment initializing a count value of the first counter to 0.

[0015] According to the first aspect, in a possible implementation, the signal quality between the first user equipment and the second user equipment is equal to or greater than a first threshold. When the signal quality is good, it indicates that the radio link is normal, and the first counter used for RLF detection does not count cases where the first feedback information is not received because the first user equipment does not receive the first feedback information. This avoids false triggering of RLF, reduces communication delay, and improves / guarantees communication quality or reliability.

[0016] According to the first aspect, in a possible implementation, when the signal quality between the first user equipment and the second user equipment is equal to or lower than a second threshold and the first user equipment fails to receive the first feedback information, the first user equipment increases the count value of the first counter by 1. When the signal quality is poor, it indicates that there may be an exception that the radio link may be abnormal. In this case, the first counter used for RLF detection counts the cases where the first feedback information is not received because the first user equipment does not receive the first feedback information, and therefore, RLF can be triggered more quickly.

[0017] According to the first aspect, in a possible implementation, the first feedback information is transmitted on a physical sidelink feedback channel PSFCH.

[0018] According to the first aspect, in a possible implementation, when the count value of the first counter is equal to or greater than a third threshold, the first user equipment sends first indication information to the network device, where the first indication information indicates that an RLF has been detected by the first user equipment, and the first user equipment triggers the RLF and reports the RLF to the network device to indicate that the radio link is abnormal.

[0019] According to a second aspect, a communication device is provided to implement the above method. The communication device includes corresponding modules, units, or means for implementing the above method. The modules, units, or means may be implemented by hardware or software, or may be implemented by hardware executing corresponding software. The hardware or software includes one or more modules or units corresponding to the above functions.

[0020] According to a second aspect, in a possible implementation, a communication device includes a transceiver module and a processing module. The transceiver module is configured to transmit first data to a second user equipment (UE) via a side link (SL). The processing module is configured to initialize a first counter or leave a count value of the first counter unchanged if first feedback information is not received. The first feedback information indicates whether the second user equipment has successfully received the first data. The first counter is used for radio link failure (RLF) detection.

[0021] According to a second aspect, in a possible implementation, the transceiver module is further configured to receive first feedback information, and if the first feedback information fails to be received, to increment a count value of the first counter by one.

[0022] According to a second aspect, in a possible implementation, not receiving the first feedback information includes not receiving the first feedback information if reception of the first feedback information conflicts with the first transmission.

[0023] According to a second aspect, in a possible implementation, not receiving the first feedback information includes receiving the first feedback information conflicts with the first transmission and the priority of receiving the first feedback information is less than or equal to the priority of the first transmission.

[0024] According to the second aspect, in a possible implementation, configuring the processing module to initialize the first counter includes configuring the processing module to initialize a count value of the first counter to 0.

[0025] According to the second aspect, in a possible implementation, the signal quality between the first user equipment and the second user equipment is greater than or equal to a first threshold.

[0026] According to a second aspect, in a possible implementation, the processing module is further configured to increase a count value of the first counter by 1 when the signal quality between the first user equipment and the second user equipment is equal to or less than a second threshold and the first feedback information fails to be received.

[0027] According to the second aspect, in a possible implementation, the first feedback information is transmitted on a physical sidelink feedback channel PSFCH.

[0028] According to a second aspect, in a possible implementation, the transceiver module is further configured to send first indication information to the network device when the count value of the first counter is greater than or equal to a third threshold, the first indication information indicating that an RLF has been detected by the first user equipment.

[0029] For technical effects provided by the second aspect and any of the possible implementations of the second aspect, please refer to the technical effects provided by the first aspect and different implementations of the first aspect, and the details will not be described again here.

[0030] According to a third aspect, a communication method is provided. A communication device performing the communication method may be a first user equipment (UE) or a module, such as a chip or chip system, used in the first user equipment. The following provides an example in which the method is performed by the first user equipment. The first user equipment transmits first data to a second user equipment (UE) via a side link (SL). If the first user equipment does not receive first feedback information, the first user equipment increases a count value of a second counter by 1. The first feedback information indicates whether the second user equipment has successfully received the first data, and the second counter is used to count the number of times that feedback information is not received consecutively by the first user equipment.

[0031] According to the third aspect, in a possible implementation, when the first user equipment receives the first feedback information, the first user equipment initializes a second counter.

[0032] According to the third aspect, in a possible implementation, the first user equipment initializing the second counter includes the first user equipment initializing the second counter to zero.

[0033] According to a third aspect, in a possible implementation, when the count value of the second counter is equal to or greater than a fourth threshold, the first user equipment transmits second indication information and / or third indication information to the network device, or the first user equipment triggers resource reselection. The second indication information indicates that an RLF has been detected by the first user equipment, indicates that an RLF has occurred, or indicates that the SL failure is caused by an RLF. The third indication information indicates that the count value of the second counter has reached (or is equal to or greater than) a fourth threshold, or that the count value of the second counter has reached 0 or a second value (or is less than or equal to), indicates that the number of times feedback information is not consecutively received by the first user equipment has reached a preset threshold (e.g., the fourth threshold), or indicates that the number of times reception of feedback information consecutively conflicts with another transmission has reached a preset threshold (e.g., the fourth threshold).

[0034] According to a third aspect, in a possible implementation, the second indication information further indicates a cause of the RLF. The cause includes that the number of times that feedback information is not consecutively received by the first user equipment reaches a fourth threshold. In this solution, the first user equipment may report the second indication information (e.g., the cause of triggering / detecting the RLF) and / or the third indication information to the network device to indicate a current high probability of resource contention. Therefore, the network device may correspondingly adjust some parameters to reduce the possibility of resource contention, thereby improving communication quality, reducing communication delay, and ensuring communication reliability.

[0035] According to the third aspect, in a possible implementation, when an RLF is triggered / detected by the first user equipment, the first user equipment may use a corresponding policy, such as restoring a unicast connection or re-establishing a unicast connection, thereby improving communication quality, reducing communication delay, and ensuring communication reliability.

[0036] According to the third aspect, in a possible implementation, the first user equipment triggers resource reselection, and thus the first user equipment can reselect resources, thereby reducing the possibility of resource contention / transmission contention, improving communication quality, reducing communication delay, and ensuring communication reliability.

[0037] According to a fourth aspect, a communication device is provided to implement the above method. The communication device includes corresponding modules, units, or means for implementing the above method. The modules, units, or means may be implemented by hardware or software, or may be implemented by hardware executing corresponding software. The hardware or software includes one or more modules or units corresponding to the above functions.

[0038] According to a fourth aspect, in a possible implementation, a communications device includes a transceiver module and a processing module. The transceiver module is configured to transmit first data to a second user equipment (UE) via a side link (SL). The processing module is configured to increase a count value of a second counter by one if first feedback information is not received. The first feedback information indicates whether the second user equipment has successfully received the first data, and the second counter is configured to count the number of times that feedback information is not received by the first user equipment consecutively.

[0039] According to the fourth aspect, in a possible implementation, the transceiver module is further configured to receive first feedback information, and the processing module is further configured to initialize a second counter.

[0040] According to the fourth aspect, in a possible implementation, the processing module being further configured to initialize the second counter includes the processing module being configured to initialize the second counter to zero.

[0041] According to a fourth aspect, in a possible implementation, the transceiver module is further configured to transmit second and / or third indication information to the network device when the count value of the second counter is equal to or greater than a fourth threshold, or the processing module is configured to trigger resource reselection. The second indication information indicates that an RLF has been detected by the first user equipment, indicates that an RLF has occurred, or indicates that the SL failure is caused by an RLF. The third indication information indicates that the count value of the second counter has reached (or is equal to or greater than) a fourth threshold, or that the count value of the second counter has reached 0 or a second value (or is less than or equal to), indicates that the number of times that feedback information is not consecutively received by the first user equipment has reached a preset threshold (e.g., the fourth threshold), or indicates that the number of times that reception of feedback information consecutively conflicts with another transmission has reached a preset threshold (e.g., the fourth threshold).

[0042] According to a fourth aspect, in a possible implementation, the second indication information further indicates a cause of the RLF, the cause including that the number of times that the feedback information is not received by the first user equipment consecutively reaches a fourth threshold.

[0043] For technical effects provided by the fourth aspect and any of the possible implementations of the fourth aspect, please refer to the third aspect and the technical effects provided by different implementations of the third aspect, and the details will not be described again here.

[0044] According to a fifth aspect, there is provided a communications device including a processor, coupled to a memory, configured to read computer instructions stored in the memory and then, based on the instructions, perform a method according to any one of the above aspects.

[0045] According to the fifth aspect, in a possible implementation, the communication device further includes a memory, the memory configured to store computer instructions.

[0046] According to a fifth aspect, in a possible implementation, the communication device further includes a communication interface, which is used by the communication device to communicate with another device. For example, the communication interface may be a transceiver, an input / output interface, an interface circuit, an output circuit, an input circuit, a pin, or an associated circuit.

[0047] According to the fifth aspect, in a possible implementation, the communication device may be a chip or a chip system. When the communication device is a chip system, the communication device may include a chip, or may include a chip and another discrete device.

[0048] According to the fifth aspect, in a possible implementation, if the communication device is a chip system or a chip system, the communication interface may be an input / output interface, an interface circuit, an output circuit, an input circuit, a pin, or an associated circuit on the chip or chip system, etc. The processor may be embodied as a processing circuit or a logic circuit.

[0049] According to a sixth aspect, there is provided a computer-readable storage medium having instructions stored thereon that, when executed on a computer, enable the computer to perform a method according to any one of the above aspects.

[0050] According to a seventh aspect, there is provided a computer program product comprising instructions, which when executed on a computer, enable the computer to perform a method according to any one of the above aspects.

[0051] For technical effects provided by any of the possible implementations of the fifth and sixth aspects, please refer to the technical effects provided by different implementations of the first and third aspects, and the details will not be described again here. [Brief explanation of the drawings]

[0052] [Figure 1] 1 is a schematic diagram of data transmission by a transmitting end using parallel HARQ processing in the prior art; [Figure 2] 1 is a schematic diagram of a HARQ-based SL RLF detection process in the prior art; [Figure 3] 1 is a schematic diagram of the architecture of a communication system according to an embodiment of the present application; [Figure 4] 1 is a schematic diagram of the structure of a communication device according to an embodiment of the present application; [Figure 5] 1 is a schematic diagram of the structure of a mobile terminal according to an embodiment of the present application; [Figure 6a] 1 is a flowchart of a communication method according to an embodiment of the present application; [Figure 6b] 4 is a flowchart of another communication method according to an embodiment of the present application. [Figure 7] 1 is a schematic diagram of a HARQ-based SL RLF detection process in the prior art and a communication method provided for the RLF detection process according to an embodiment of the present application; FIG. [Figure 8]4 is a flowchart of yet another communication method according to an embodiment of the present application. [Figure 9] FIG. 10 is a schematic diagram of the structure of another communication device according to an embodiment of the present application; DETAILED DESCRIPTION OF THE INVENTION

[0053] In order to facilitate understanding of the technical solutions in the embodiments of the present application, the following first provides a brief description of the technologies or terms related to the present application.

[0054] The first is vehicle-to-everything (V2X).

[0055] In V2X communication, a communication link for direct communication between an end device and another end device is established. ,sa The wireless communication link from the terminal device to the network device may be referred to as an uplink (UL). The wireless communication link from the network device to the terminal device may be referred to as a downlink (DL). The UL or DL ​​interface may be referred to as a Uu interface, so the UL or DL ​​may be referred to as a Uu interface link.

[0056] NR V2X supports unicast, multicast, and broadcast services.

[0057] It should be noted that in this application, terminal, terminal device, user equipment, and UE may be interchangeable.

[0058] The second is hybrid automatic repeat request (HARQ).

[0059] (1) HARQ Feedback

[0060] Possible HARQ feedback mechanisms are as follows: if the data is successfully received, the receiving end feeds back an acknowledgement (ACK) to the transmitting end, and if the data is not received successfully, the receiving end feeds back a negative acknowledgement (NACK) to the transmitting end.

[0061] NR V2X supports SL HARQ feedback for unicast and multicast.

[0062] (2) HARQ processing

[0063] HARQ uses a stop-and-wait protocol to control data transmission. Specifically, after transmitting a transport block (TB), the transmitter stops and waits until feedback information for the TB is received before transmitting the next TB. The process of the transmitter stopping transmission and waiting for feedback information causes a decrease in throughput.

[0064] To improve throughput, the transmitting end may use multiple parallel HARQ processes. Specifically, while waiting for feedback information of one HARQ process, the transmitting end may continue to transmit data by using another HARQ process. For example, as shown in FIG. 1, the transmitting end transmits TB1 by using a first HARQ process, and the transmission of TB1 is completed at time T1. The transmitting end waits for feedback information of TB1 until the feedback information of TB1 is received by the transmitting end at time T2. During the waiting time T1 to T2, the transmitting end may transmit TB2 by using a second HARQ process. Similarly, after the transmission of TB2 is completed at time T2, the transmitting end waits for feedback of TB2 until the feedback of TB2 is received by the transmitting end at time T3. During the waiting time T2 to T3, the transmitting end may transmit TB3 by using a third HARQ process.

[0065] It should be noted that an HARQ process on the Uu interface may be referred to as an HARQ process. On the Uu interface, one HARQ process may be identified by using one HARQ process identification (process ID), in other words, one HARQ process may be associated with one HARQ process ID.

[0066] Note that in NR V2X, a HARQ process over a SL is sometimes referred to as a SL process.

[0067] The third is SL processing.

[0068] On the SL, a transmitting user equipment (UE) may transmit sidelink control information (SCI) and SL data to one or more receiving UEs. The SCI is used to schedule the SL data.

[0069] In NR V2X, the SCI may include a first level SCI and a second level SCI.

[0070] Since the SL data is transmitted via the physical sidelink shared channel (PSSCH), the SL data is sometimes referred to as the PSSCH, which is described uniformly in this specification and will not be described in detail below. The first-level SCI and the second-level SCI are described separately below.

[0071] The first level SCI may be used to schedule the second level SCI and SL data / PSSCH, and may be transmitted over a physical sidelink control channel (PSCCH).

[0072] The second level SCI may be used to decode the SL data / PSSCH.

[0073] The SCI or second level SCI may include an SL process ID, a first destination ID, a first source ID, and a communication type (cast type).

[0074] In NR V2X, one ID set may identify one SL process, or one SL process may be associated with one ID set.

[0075] The ID set may include an SL process ID, a first destination ID, a first source ID, and a communication type; the ID set may include an SL process ID, a first destination ID, and a first source ID; the ID set may include an SL process ID, a second destination ID, a second source ID, and a communication type; or the ID set may include an SL process ID, a second destination ID, and a second source ID.

[0076] The SL processing ID, first destination ID, second destination ID, first source ID, second source ID, and communication type will be explained individually below.

[0077] (1)SL processing ID

[0078] The SL process ID may be used to identify the SL process.

[0079] (2) First destination ID and second destination ID

[0080] The first destination ID may be used to identify a target of the SL data scheduled by the SCI. Optionally, the first destination ID may be used by the physical layer of the receiving end UE to filter data packets. For example, the first destination ID may be a destination layer-1 ID. For example, layer 1 may represent the first layer, i.e., the physical layer, in the open system interconnection reference model (OSI reference model).

[0081] For example, the first destination ID may be some bits of the second destination ID. For example, if the second destination ID is 24 bits, the first destination ID may be the lower 16 bits of the second destination ID.

[0082] The second destination ID may be used to identify a target (e.g., target) / receiving end / receiving terminal of the data. For example, the second destination ID may be used to identify a multicast or broadcast service. For example, the second destination ID may be an identifier of the target / receiving end / receiving terminal. For example, the second destination ID may be a Destination Layer-2 ID. Optionally, the second destination ID may be used by a media access control (MAC) layer of a receiving terminal to filter data packets. For example, Layer 2 represents the second layer in the OSI module, i.e., the data link layer, which includes the MAC layer.

[0083] (3) First sender ID and second sender ID

[0084] The first source ID may be used to identify the source of the SL data scheduled by the SCI. Optionally, the first source ID may be used to perform data packet filtering at the PHY layer of the receiving terminal. For example, the first source ID may be a source layer-1 ID.

[0085] For example, the first source ID may be some bits of the second source ID. For example, if the second source ID is 24 bits, the first source ID may be the lowest 8 bits of the second source ID. The second source ID may be used to identify the source or transmitting end of the data. For example, the second source ID may be a source layer-2 ID.

[0086] (4) Communication type

[0087] The communication type may include one or more of unicast, multicast, and broadcast. The communication type in the SCI indicates that the current communication is unicast, multicast, or broadcast. Alternatively, the communication type in the SCI indicates that the SL data scheduled by the SCI is unicast data, multicast data, or broadcast data.

[0088] For example, a pair of a second source ID and a second destination ID may identify one unicast.

[0089] For example, in the case of unicast, the second destination ID and the second source ID may be used when the MAC layer of the receiving end UE filters the data packets.

[0090] For example, in the case of unicast, the first destination ID and the first source ID may be used when the physical layer of the receiving end UE filters the data packet.

[0091] Fourth, the reception of the physical sidelink feedback channel (PSFCH) competes with other transmissions / receptions.

[0092] For example, three cases where reception of the PSFCH conflicts with another transmission / reception are described below.

[0093] For example, the contention may include contention in the time domain or contention in a slot.

[0094] For example, conflict may be understood / replaced as overlap or agreement.

[0095] The reception of the PSFCH is associated with SCI1 and / or SL data 1. It may be understood that after the transmitting end UE transmits SCI1 and / or SL data 1 to the receiving end UE, the transmitting end UE may receive SL HARQ feedback (which may be understood as reception of the PSFCH) of the receiving end UE on PSFCH resource 1.

[0096] (1) PSFCH reception conflicts with PSFCH transmission.

[0097] Reception of the PSFCH (for transmission of SL data 1) competes with transmission of the PSFCH (associated with other data transmissions). If the priority of reception of the PSFCH is equal to or lower than the priority of transmission of the PSFCH (or if reception of the PSFCH has no priority), the transmitting end UE of SL data 1 transmits the PSFCH but does not receive it. Therefore, the PSFCH is not received by the transmitting end UE of SL data 1.

[0098] It should be noted that the transmitting end UE of SL data 1 may also be used as the receiving end UE of SL data 2, and may transmit the PSFCH to the transmitting end UE of SL data 2.

[0099] It should be noted that the priority of receiving or transmitting the PSFCH is determined by the priority of the SL data associated with the PSFCH. A priority field in the SCI or first level SCI corresponding to the SL data carries the priority information of the SL data. A smaller value in the priority field indicates a higher priority of the SL data.

[0100] (2) Reception of PSFCH competes with UL transmission.

[0101] Reception of the PSFCH (for transmission of SL data 1) competes with UL transmission. If the priority of reception of the PSFCH is equal to or lower than the priority of UL transmission (or if reception of the PSFCH is not prioritized), the transmitting end UE performs UL transmission but does not receive the PSFCH. Therefore, the PSFCH is not received by the transmitting end UE. "Transmission" may be understood as "transmission and / or reception."

[0102] For example, the reception of the PSFCH (for the transmission of SL data 1) competing with UL transmission may include the reception of the PSFCH (for the transmission of SL data 1) competing with UL transmission within one slot. Note that in a possible implementation, the priority of the reception of the PSFCH within one slot may be the highest priority among the priorities of the SL data corresponding to multiple PSFCHs within that slot.

[0103] (3) Reception of the NR SL PSFCH competes with long term evolution (LTE) SL transmission.

[0104] In NR SL transmission, reception of the PSFCH competes with LTE SL transmission in terms of time at the transmitting UE. If the priority of reception of the PSFCH is equal to or lower than the priority of LTE SL transmission (or in other words, if reception of the PSFCH is not prioritized), the transmitting UE performs LTE SL transmission but does not receive the PSFCH. Therefore, the PSFCH is not received by the transmitting UE.

[0105] It should be noted that the priority of receiving or transmitting the PSFCH is determined by the priority of the SL data associated with the PSFCH. A priority field in the SCI or first level SCI corresponding to the SL data carries the priority information of the SL data. A smaller value in the priority field indicates a higher priority of the SL data.

[0106] It should be noted that different priority levels are defined in the NR system and the LTE system. For a comparison of transmission priorities in the two systems, please refer to the prior art. The details will not be repeated here.

[0107] It should be noted that the above contention can be understood as a contention at one UE (the transmitting UE).

[0108] It should be noted that the sending end may be understood as the sending end of the data.

[0109] The above conflict situations and priority comparisons in conflict situations belong to the prior art. Details will not be described again here. For specific details, please refer to the descriptions in Non-Patent Document 1 and Non-Patent Document 2. Details will not be described again here.

[0110] The fifth is HARQ-based SL radio link failure (RLF) detection.

[0111] In NR V2X, HARQ-based SL RLF detection is introduced for unicast connections. The transmitting UE uses a counter to PSFCHThe counter counts the number of times the PSFCH is not received consecutively. Specifically, if the transmitting UE fails to receive the PSFCH, the transmitting UE increments the counter value by 1. If the PSFCH is received by the transmitting UE, the transmitting UE initializes / sets the counter value to 0. If the counter value reaches a threshold, the transmitting UE triggers RLF. For details, see Section 5.22.1.3.3 of Non-Patent Document 2.

[0112] A unicast connection is established or a threshold is configured or reconfigured. The transmitting end UE initializes / sets the count value of the counter to 0.

[0113] The counter may be numConsecutiveDTX. The threshold may be sl-maxNumConsecutiveDTX. The value of the threshold may be set by the network device, or the value of the threshold may be pre-set.

[0114] For example, Figure 2 shows a HARQ-based SL RLF detection process. The initial value of the counter is 0. The threshold for triggering an RLF is 3. For example, a PSFCH monitoring occasion can be understood as a PSFCH, a position of a PSFCH, a time-domain position of a PSFCH, or a PSFCH reception opportunity. Note that Figure 2 only shows 11 PSFCH monitoring occasions as an example. The actual PSFCH monitoring occasions may be continuous or discontinuous in the time domain, or alternatively, different PSFCH monitoring occasions may overlap in the time domain. This is not a limitation in this embodiment of the present application.

[0115] The transmitting end UE "receiving" the PSFCH indicates that the transmitting end UE performs an operation of "receiving" the PSFCH. The result of "receiving" the PSFCH by the transmitting end UE may be that the PSFCH is "received by" the transmitting end UE, or that the transmitting end UE "fails to receive" the PSFCH.

[0116] The transmitting end UE "not receiving" the PSFCH indicates that the transmitting end UE does not perform an operation to "receive" the PSFCH. When the transmitting end UE's "receiving" the PSFCH conflicts with another transmission / reception of the transmitting end UE, the priority of the "receiving" of the PSFCH is lower than the priority of the other transmission / reception (or the "receiving" of the PSFCH has no priority), so the transmitting end UE performs the other transmission / reception but does not perform an operation to "receive" the PSFCH. The result of the transmitting end UE "not receiving" the PSFCH is that the PSFCH is "not received by" the transmitting end UE.

[0117] In the first PSFCH monitoring opportunity, the PSFCH reception conflicts with another transmission and does not have priority, so the transmitting UE does not receive the PSFCH. Therefore, the PSFCH is not received by the transmitting UE. In the existing protocol, the count value of the counter is incremented by 1, and the initial value is changed from 0 to 1.

[0118] In the second PSFCH monitoring opportunity, the transmitting UE receives the PSFCH but fails to receive the PSFCH, and in the existing protocol, the counter value is incremented by one to become two.

[0119] In the third PSFCH monitoring opportunity, the PSFCH is received by the transmitting UE. In the existing protocol, the count value of the counter is initialized / set to 0.

[0120] In the fourth PSFCH monitoring opportunity, the transmitting UE receives the PSFCH but fails to receive the PSFCH, and in the existing protocol, the count value of the counter is incremented by one to become 1.

[0121] In the fifth PSFCH monitoring opportunity, the transmitting UE receives the PSFCH but fails to receive the PSFCH, and in the existing protocol, the count value of the counter is increased by one to become two.

[0122] At the sixth PSFCH monitoring opportunity, the receiving of the PSFCH conflicts with another transmission of the PSFCH, and the receiving of the PSFCH does not have priority, so the transmitting UE does not receive the PSFCH. Therefore, the PSFCH is not received by the transmitting UE. In the existing protocol, the count value of the counter is incremented by 1 to become 3. Since the count value of the counter in the existing protocol has reached the threshold, the transmitting UE triggers RLF.

[0123] In the seventh PSFCH monitoring opportunity, the PSFCH is received by the transmitting UE. In the existing protocol, the count value of the counter is initialized / set to 0.

[0124] In the eighth PSFCH monitoring opportunity, the transmitting UE does not receive the PSFCH because the reception of the PSFCH conflicts with another transmission of the PSFCH and the reception of the PSFCH does not have priority. Therefore, the PSFCH is not received by the transmitting UE. In the existing protocol, the count value of the counter is incremented by 1 and the initial value is changed from 0 to 1.

[0125] In the ninth PSFCH monitoring opportunity, the transmitting UE does not receive the PSFCH because the reception of the PSFCH conflicts with another transmission of the PSFCH and the reception of the PSFCH does not have priority. Therefore, the PSFCH is not received by the transmitting UE. In the existing protocol, the count value of the counter is incremented by 1 to become 2.

[0126] In the tenth PSFCH monitoring opportunity, the PSFCH is received by the transmitting UE. In the existing protocol, the count value of the counter is initialized / set to 0.

[0127] In the 11th PSFCH monitoring opportunity, the PSFCH is received by the transmitting UE. In the existing protocol, the count value of the counter is initialized / set to 0, or the count value of the first counter is left unchanged and remains 0.

[0128] It should be understood that the seventh PSFCH monitoring opportunity and subsequent PSFCH monitoring opportunities in Figure 2 may refer to PSFCHs corresponding to SL transmissions that occur after the unicast connection is restored. It can be understood that the seventh PSFCH monitoring opportunity and subsequent PSFCH monitoring opportunities in Figure 2 may not exist to restore the unicast connection after the RLF is triggered.

[0129] From the above analysis, it can be seen that the counter value is 2 at the fifth PSFCH monitoring opportunity. At the sixth PSFCH monitoring opportunity, the PSFCH is not received by the transmitting UE, not because of a problem in the radio link, but because the transmitting UE does not receive the PSFCH. In the existing HARQ-based SL RLF detection, the counter value is incremented by 1 at the sixth PSFCH monitoring opportunity. As a result, the counter value reaches the threshold value of 3, and the transmitting UE falsely triggers an RLF. This results in increased communication delay and reduced communication quality or reliability. In particular, when the threshold value is 1, the transmitting UE is more likely to falsely trigger an RLF by using the existing HARQ-based SL RLF detection.

[0130] Note that currently, in NR V2X, HARQ-based SL RLF detection is performed for unicast connections and counters are maintained separately for each unicast connection. In this specification, the number of consecutive times that the PSFCH is not received can be understood as the number of consecutive times that the PSFCH is not received for a unicast connection (e.g., one unicast connection) or the number of consecutive times that the PSFCH is not received for all sidelink processing of a unicast connection (e.g., one unicast connection).

[0131] A unicast connection may also be referred to as a SL radio resource control (RRC) connection or a PC5-RRC connection. A unicast connection may be a logical connection between a pair of second source ID and second destination ID. Alternatively, a unicast connection may be a logical connection between a pair of second source ID and second destination ID in the access stratum (AS). A unicast connection may include / be replaced by / correspond to any one or more of: unicast, unicast connection, destination address, and an ID pair of second source ID and second destination ID. A destination address may be understood as a corresponding ID pair of second source ID and second destination ID.

[0132] For example, RLF in this application may be understood to include / include SL RLF.

[0133] For example, initialization in this application may be replaced with / including reinitialization.

[0134] For example, the first user equipment in the present application may include / be replaced with a first user equipment HARQ entity, a first user equipment SL HARQ entity, or a first user equipment MAC entity.

[0135] For example, a unicast connection in this application may include / be replaced with one unicast connection or a first unicast connection.

[0136] For example, an SL process associated with a unicast connection in this application may include / be replaced with any one or more of an SL process associated with a destination address, an SL process associated with a second source ID and a second destination ID pair, and an SL process associated with a first source ID and a first destination ID pair.

[0137] The following describes the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. In the description of the present application, " / " represents an "or" relationship between associated objects unless otherwise specified. For example, A / B may represent A or B. In the present application, "and / or" only describes the association relationship between associated objects and represents that three relationships may exist. For example, A and / or B may represent the following three cases: only A exists, both A and B exist, and only B exists, where A and B may be singular or plural. Also, in the description of the present application, "plurality" means two or more unless otherwise specified. "At least one of the following pieces" or similar expressions refer to any combination of these elements, including any combination of a single piece or multiple pieces. For example, at least one piece of a, b, or c may refer to a, b, c, a and b, a and c, b and c, or a, b, and c, where a, b, and c may be singular or plural. Also, in order to clearly describe the technical solutions in the embodiments of the present application, terms such as "first" and "second" are used to distinguish between identical or similar terms that provide basically the same function or application in the embodiments of the present application. Those skilled in the art can understand that terms such as "first" and "second" do not limit the quantity or execution order, and terms such as "first" and "second" do not indicate clear distinctions.

[0138] It should be noted that in this application, terms such as "example" or "for example" are used to denote providing an example, illustration, or explanation. Any embodiment or design scheme described in the embodiments of this application as an "example" or "for example" should not be described as being preferred or having more advantages than other embodiments or design schemes. Rather, the use of words such as "example" or "for example" is intended to present the relevant concept in a particular way.

[0139] The methods provided in the embodiments of the present application are applicable to, but not limited to, the following fields: device to device (D2D), V2X, unmanned driving, automated driving (ADS), driver assistance (ADAS), intelligent driving, connected driving, intelligent network driving, and car sharing.

[0140] In embodiments of the present application, communication systems include, but are not limited to, long term evolution (LTE) systems, fifth generation (5G) systems, new radio (NR) systems, wireless local area network (WLAN) systems, and future evolved systems or multiple converged communication systems. The 5G system may be a non-standalone (NSA) 5G system or a standalone (SA) 5G system.

[0141] A network device in an embodiment of the present application is a network-side entity configured to transmit signals, receive signals, or transmit and receive signals. The network device may be a device located on a radio access network (RAN) and providing wireless communication functions for terminals. For example, the network device may be a transmission reception point (TRP), a base station, or various forms of control nodes (e.g., a network controller and a radio controller (e.g., a radio controller in a cloud radio access network (CRAN) scenario)). Specifically, the network device may be various forms of macro base stations, micro base stations (also called small cells), relay stations, or access points (APs), or may be an antenna panel of a base station. A control node may be connected to multiple base stations and configure resources for multiple terminals within the coverage of the multiple base stations. In systems using different radio access technologies, the name of a device having the functionality of a base station may be different. For example, a device having the functionality of a base station may be called an evolved NodeB (eNB or eNodeB) in an LTE system, or a next generation node base station (gNB) in a 5G system or an NR system. The specific name of the base station is not limited in this application. Alternatively, the network device may be a network device in a future evolved public land mobile network (PLMN), etc.

[0142] A terminal in an embodiment of the present application is a user-side entity configured to receive signals, transmit signals, or receive and transmit signals. The terminal is configured to provide one or more of voice services and data connection services to a user. A terminal may also be called user equipment (UE), a terminal device, an access terminal, a subscriber unit, a subscriber station, a mobile station, a remote station, a remote terminal, a mobile device, a user terminal, a wireless communication device, a user agent, or a user equipment. The terminal may be a V2X device, such as a smart car (or an intelligent car), a digital car, an unmanned car (also called a driverless car, a pilotless car, or an automobile), a self-driving car (or an autonomous car), a pure electric vehicle (or a battery EV), a hybrid electric vehicle (HEV), a range extended electric vehicle (REEV), a plug-in hybrid electric vehicle (PHEV), a new energy vehicle, or a road site unit (RSU). Alternatively, the terminal may be a D2D device, such as an electricity meter or a water meter.Alternatively, the terminal may be a mobile station (MS), a subscriber unit, an unmanned aerial vehicle, an internet of things (IoT) device, a station (ST) in a WLAN, a cellular phone, a smartphone, a cordless phone, a wireless data card, a tablet computer, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA) device, a laptop computer, a machine type communication (MTC) terminal, a handheld device with wireless communication capabilities, a computing device, another processing device connected to a wireless modem, an in-vehicle device, or a wearable device (sometimes referred to as a wearable intelligent device). Alternatively, the terminal may be a terminal in a next generation communication system, such as a terminal in a 5G system, a terminal in a future evolved PLMN, or a terminal in an NR system.

[0143] The embodiments of the present application may be applicable to an NR system, or may be applicable to another system, for example, another future-oriented new system, which is not particularly limited in the embodiments of the present application. Also, the terms "system" and "network" are interchangeable.

[0144] 3 shows a communication system 30 according to an embodiment of the present application. The communication system 30 includes one or more user equipments 301. Different user equipments 301 can communicate with each other via SL.

[0145] For example, the first user equipment in this embodiment of the present application may be one of any two user equipments 301 that communicate with each other, and the other user equipment may be the second user equipment in this embodiment of the present application.

[0146] Optionally, the communication system further includes a network device 302. The network device 302 may individually communicate with the user equipment 301 via an UL or DL. For example, in a broadcast scenario, to ensure that another terminal device having a service discontinuous reception (DRX) requirement can receive the broadcast signal, the user equipment 301 may send associated requirement information to the network device 302. This is not particularly limited in the embodiment of the present application.

[0147] It should be noted that Figure 3 is only a schematic diagram. The communication system 30 may further include other network devices, such as one or more of a core network device, a wireless relay device, and a wireless backhaul device, but the other network devices are not shown in Figure 3. This is not particularly limited in this specification. The network devices may be connected to the core network device in a wireless or wired manner. The core network device and the network device 302 may be different and independent physical devices, and the functions of the core network device and the logical functions of the network device 302 may be integrated into the same physical device, or some functions of the core network device and some functions of the network device 302 may be integrated into one physical device. This is not particularly limited in the embodiments of the present application.

[0148] Optionally, the network device 302 in this embodiment of the present application is a device that enables the user equipment 301 to access a wireless network. The network device 302 may be a base station, an evolved NodeB (eNodeB), a transmission reception point (TRP), a next generation NodeB (gNB) in a 5G mobile communication system, a base station in a future mobile communication system, an access node in a wireless fidelity (Wi-Fi) system, etc., or may be a module or unit that performs some of the functions of a base station, such as a central unit (CU) or a distributed unit (DU). The specific technology used by the network device and the specific device form are not limited in the embodiments of the present application. In this application, unless otherwise specified, the network device is a radio access network device.

[0149] Optionally, the user equipment 301 in this embodiment of the present application may be a vehicle, or may be an on-board terminal or a chip in the on-board terminal that is installed in a vehicle and configured to assist in driving the vehicle. Alternatively, the user equipment 301 in this embodiment of the present application may be a device configured to implement wireless communication functions, such as a terminal or a chip that can be used in a terminal. The on-board terminal or terminal may be a UE, access terminal, terminal unit, end station, mobile station, remote station, remote terminal, mobile device, wireless communication device, terminal agent, or UE in a 5G network or a future evolved public land mobile network (PLMN). The access terminal may be a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a handheld device with wireless communication capabilities, a computing device or another processing device connected to a wireless modem, an in-vehicle device or a wearable device, a virtual reality (VR) UE, an augmented reality (AR) UE, a wireless terminal in industrial control or a wireless terminal in self-driving, a wireless terminal in telemedicine, a wireless terminal in a smart grid, a wireless terminal in transportation safety, a wireless terminal in a smart city, a wireless terminal in a smart home, etc. The user equipment 301 may be in a fixed location or may be mobile, which is not particularly limited in this embodiment of the present application.

[0150] Optionally, in this embodiment of the present application, the user equipment 301 includes a hardware layer, an operating system layer running on the hardware layer, and an application layer running on the operating system layer. The hardware layer includes hardware such as a central processing unit (CPU), a memory management unit (MMU), and memory (also referred to as main memory). The operating system may be any one or more types of computer operating systems that implement service processing through processes, such as a Linux operating system, a Unix operating system, an Android operating system, an iOS operating system, or a Windows operating system. The application layer includes applications such as a browser, an address book, word processing software, and instant messaging software. Furthermore, the specific structure of the execution entity of the method provided in the embodiment of the present application is not particularly limited in the embodiment of the present application, as long as a program recording the code of the method provided in the embodiment of the present application can be executed to communicate according to the method provided in the embodiment of the present application. For example, the method provided in this embodiment of the present application may be executed by the user equipment 301, or may be a functional module located within the user equipment 301 that can call and execute a program.

[0151] In other words, the related functions of the user equipment 301 in this embodiment of the present application may be implemented by one device, may be implemented together by multiple devices, or may be implemented by one or more function modules in one device. This is not particularly limited in this embodiment of the present application. It may be understood that the above functions may be network elements in a hardware device, software functions running on dedicated hardware, a combination of hardware and software, or virtualized functions instantiated on a platform (e.g., a cloud platform).

[0152] For example, the associated functions of the user equipment 301 in this embodiment of the present application may be implemented by using a communication device 40 of Fig. 4. Fig. 4 is a schematic diagram of the structure of the communication device 40 according to an embodiment of the present application. The communication device 40 includes one or more processors 401, a communication line 402, and at least one communication interface (in Fig. 4, an example including a communication interface 404 and one processor 401 is used for illustration purposes only), and may optionally further include a memory 403.

[0153] The processor 401 may be a CPU, a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling program execution of the solution of the present application.

[0154] Communication lines 402 may include paths for connecting different components.

[0155] The communication interface 404 may be a transceiver module configured to communicate with another device or communication network, such as an Ethernet, a RAN, or a wireless local area network (WLAN). For example, the transceiver module may be a device such as a transceiver device or a transceiver unit. Optionally, the communication interface 404 may alternatively be a transceiver circuit located in the processor 401 and configured to implement signal inputs and outputs of the processor.

[0156] The memory 403 may be a device having a storage function. For example, the memory may be a read-only memory (ROM) or another type of static storage device capable of storing static information and instructions, a random access memory (RAM) or another type of dynamic storage device capable of storing information and instructions, or an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other compact disc storage, an optical disc storage (including compressed optical discs, laser discs, optical discs, digital versatile discs, and Blu-ray discs, etc.), a magnetic disc storage medium or other magnetic storage device, or any other medium capable of carrying or storing program code expected in the form of instructions or data structures and accessible by a computer. However, the memory is not limited thereto. The memory may exist independently and be connected to the processor via communication line 402. Alternatively, the memory may be integrated into the processor.

[0157] The memory 403 is configured to store computer-executable instructions for executing the solutions in the present application, and the processor 401 controls the execution. The processor 401 is configured to execute the computer-executable instructions stored in the memory 403 to implement the communication methods provided in the embodiments of the present application.

[0158] Alternatively, in this embodiment of the present application, the processor 401 may implement functions related to processing in the communication methods provided in the following embodiments of the present application, and the communication interface 404 is responsible for communication with another device or a communication network, which is not particularly limited in this embodiment of the present application.

[0159] The computer-executable instructions in the application embodiments may also be referred to as application program code, which is not particularly limited in the application embodiments.

[0160] In a specific implementation, in an embodiment, the processor 401 may include one or more CPUs, for example, CPU0 and CPU1 in FIG.

[0161] In a specific implementation, in an embodiment, communications device 40 may alternatively include multiple processors, such as processor 401 and processor 407 in FIG. 4. Each of the processors may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. A processor herein may be one or more devices, circuits, and / or processing cores configured to process data (e.g., computer program instructions).

[0162] In a specific implementation, in an embodiment, the communication device 40 may further include an output device 405 and an input device 406. The output device 405 communicates with the processor 401 and may display information in multiple ways.

[0163] The communication device 40 may be a general-purpose device or a dedicated device. For example, the communication device 40 may be a desktop computer, a portable computer, a network server, a personal digital assistant (PDA), a mobile phone, a tablet computer, a wireless terminal device, an in-vehicle terminal device, an embedded device, or a device having a structure similar to that of the device in FIG. 4. The type of the communication device 40 is not limited in the embodiments of the present application.

[0164] For example, the user equipment 301 in Figure 3 is a mobile terminal. Figure 5 is a schematic diagram of the structure of a mobile terminal 50.

[0165] As shown in FIG. 5, the mobile terminal 50 may include a processor 510, an external memory interface 520, an internal memory 521, a USB interface 530, a mobile communication module 540, a wireless communication module 550, an audio module 560, a sensor module 570, a camera 580, and a display 581, etc.

[0166] It may be understood that the structure shown in this embodiment of the present application does not constitute a particular limitation on the mobile terminal 50. In some other embodiments of the present application, the mobile terminal 50 may include more or fewer components than those shown in the figures, or some components may be combined, or some components may be divided, or a different component arrangement may be used. The components shown in the figures may be implemented by hardware, software, or a combination of software and hardware.

[0167] In this embodiment of the present application, the processor 510 may include one or more processing units. For example, the processor 510 may include an application processor (AP), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, a memory, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural processing unit (NPU), etc. The different processing units may be separate components or may be integrated into one or more processors.

[0168] Additionally, memory configured to store instructions and data may be further disposed within processor 510. In some embodiments, the memory within processor 510 is a cache. The memory may store instructions or data that have been recently used or that are periodically used by processor 510. When instructions or data need to be used again, processor 510 may retrieve the instructions or data directly from memory. This avoids repeated accesses and reduces the wait time of processor 510, thereby improving system efficiency.

[0169] In this embodiment of the present application, the wireless communication function of the mobile terminal 50 may be implemented by using antenna 1, antenna 2, mobile communication module 540, wireless communication module 550, modem processor, and baseband processor, etc.

[0170] Antenna 1 and Antenna 2 are configured to transmit and receive electromagnetic signals.

[0171] Mobile communication module 540 may provide solutions including second generation (2G) / third generation (3G) / fourth generation (4G) / fifth generation (5G) or other wireless communication applicable to mobile terminal 50. In some embodiments, at least some functional modules of mobile communication module 540 may be disposed within processor 510. In some embodiments, at least some functional modules of mobile communication module 540 and at least some modules of processor 510 may be disposed in the same component.

[0172] The wireless communication module 550 may provide solutions including WLAN (e.g., Bluetooth (BT), wireless fidelity (Wi-Fi) networks), global navigation satellite system (GNSS), near field communication (NFC), infrared (IR), frequency modulation (FM), or other wireless communication applicable to the mobile terminal 50.

[0173] In some embodiments, antenna 1 of mobile terminal 50 is coupled to mobile communication module 540 and antenna 2 is coupled to wireless communication module 550, thus enabling mobile terminal 50 to communicate with networks and other devices via wireless communication technologies.

[0174] In this embodiment of the present application, the mobile terminal 50 implements display functionality via a GPU, a display 581, an application processor, etc. The GPU is a microprocessor for image processing and is connected to the display 581 and the application processor. The GPU is configured to perform mathematical and geometric calculations for graphics rendering. The processor 510 may include one or more GPUs that execute program instructions to generate or modify display information.

[0175] The display 581 is configured to display images, videos, or the like. The display 581 may include a display panel. The display panel may be a liquid crystal display (LCD), an organic light-emitting diode (OLED), an active-matrix organic light-emitting diode (AMOLED), a flexible light-emitting diode (FLED), a mini-LED, a micro-LED, a micro-OLED, or a quantum dot light-emitting diode (QLED), or the like. In some embodiments, the mobile terminal 50 may include one or N displays 581, where N is a positive integer greater than 1.

[0176] In this embodiment of the present application, the mobile terminal 50 may implement a photography function via an ISP, a camera 580, a video codec, a GPU, a display 581, an application processor, and the like.

[0177] The camera 580 is configured to capture still images or video. An optical image of an object is generated through a lens and projected onto a photosensitive element. The photosensitive element may be a charge coupled device (CCD) or a complementary metal-oxide-semiconductor (CMOS) phototransistor. The photosensitive element converts the optical signal into an electrical signal, which is then transmitted to an ISP, which converts the electrical signal into a digital image signal. The ISP outputs the digital image signal to a DSP for processing. The DSP converts the digital image signal into an image signal in a standard format, such as RGB or YUV. In some embodiments, the mobile terminal 50 may include one or N cameras 580, where N is a positive integer greater than 1.

[0178] In this embodiment of the present application, the external memory interface 520 may be configured to connect to an external storage card, such as a microSD card, to expand the storage capabilities of the mobile terminal 50. The external storage card communicates with the processor 510 via the external memory interface 520 to implement data storage functions. For example, files such as music and videos are stored on the external storage card.

[0179] In this embodiment of the present application, the internal memory 521 may be configured to store computer-executable program code. The executable program code includes instructions. The internal memory 521 may include a program storage area and a data storage area. The program storage area may store an operating system, applications required by at least one function (e.g., audio playback function and image display function), etc. The data storage area may store data (e.g., audio data or an address book) created in a process using the mobile terminal 50, etc. Furthermore, the internal memory 521 may include high-speed random access memory and may further include non-volatile memory such as at least one magnetic disk storage component, flash memory, or universal flash storage (UFS). The processor 510 performs various functional applications and data processing of the mobile terminal 50 by executing instructions stored in the internal memory 521 and / or instructions stored in memory disposed in the processor.

[0180] In this embodiment of the present application, the sensor module 570 may include an acceleration sensor, a gyro sensor, a GPS sensor, a touch sensor, and the like.

[0181] Of course, the mobile terminal 50 may further include a charging management module, a power management module, a battery, a button, an indicator, one or more subscriber identity module (SIM) card interfaces, etc., which is not limited in this embodiment of the present application.

[0182] In the prior art, when the time for the transmitting end to receive the PSFCH conflicts with the time for the transmitting end to transmit or receive other information, if the priority of the transmitting end to transmit or receive other information is higher than the priority of receiving the PSFCH, the transmitting end will transmit or receive the other information and will not be able to receive the PSFCH. Obviously, this is not caused by a radio link problem that causes the transmitting terminal to fail to receive the PSFCH. However, in this case, because the transmitting end fails to receive the PSFCH, the transmitting end still increments the count value of the counter by 1, which may cause the count value of the counter to reach a preset threshold. As a result, the transmitting end may erroneously trigger an RLF, affecting communication quality and causing communication delays, thereby affecting communication quality.

[0183] According to the content of the existing protocol, if the RLF is falsely triggered, a certain time may be required between the transmitting end and the receiving end to recover / re-establish the connection (e.g., unicast connection) and continue normal communication. It can be understood that the false triggering of the RLF will cause a certain communication delay and also affect the communication quality.

[0184] To describe in detail the communication method provided in the embodiments of the present application, the following will use an example in which the first user equipment is one of any two user equipments 301 that communicate with each other, with reference to Figures 1 to 5.

[0185] In the following method embodiments, only the example in which the execution entities are the first user equipment and the second user equipment is used, but it should be understood that the execution entities are not necessarily limited to the first user equipment and the second user equipment. The first user equipment and the second user equipment can be replaced with devices that can implement this method in the present application. For example, the first user equipment can also be replaced with a chip or a first device configured in the first user equipment, and the second user equipment can also be replaced with a chip or a second device configured in the second user equipment.

[0186] 6a shows a communication method according to an embodiment of the present application. The communication method includes the following steps:

[0187] S601: A first user equipment transmits first data to a second user equipment via an SL.

[0188] Optionally, step S601 may include / be replaced by the first user equipment sending first data to the second user equipment via the SL for a unicast connection.

[0189] For example, the first data may be SL data.

[0190] Optionally, step S601 may be replaced by the first user equipment transmitting first control information to the second user equipment via SL, or the first user equipment transmitting first control information and first data to the second user equipment via SL.

[0191] The first control information is used to schedule the first data.

[0192] For example, the first control information may be an SCI or a first level SCI.

[0193] It may be understood that the first user equipment may transmit only the first control information to the second user equipment via the SL, or may transmit both the first control information and the first data to the second user equipment via the SL. For example, the first user equipment may transmit the first control information to the second user equipment via the SL but fail to transmit the first data for some reason (e.g., the transmission of the first data conflicts with other transmissions).

[0194] It should be noted that the solution in this application may also be applicable to scenarios / systems other than SL, and "via SL" in step S601 is deleted (i.e., the link for transmitting the first data and / or the first control information is not limited), and the first user equipment and the second user equipment are replaced with the first device and the second device for understanding.

[0195] After step S601, the first user equipment may perform any one or more of the following steps S602, S603, and S604.

[0196] S602: If the first user equipment does not receive the first feedback information, the first user equipment initializes a first counter or keeps the count value of the first counter unchanged.

[0197] Optionally, step S602 may include / be replaced by, for a unicast connection, if the first user equipment does not receive the first feedback information, the first user equipment initializes a first counter or leaves the count value of the first counter unchanged.

[0198] The first feedback information may indicate whether the second user equipment successfully received the first data.

[0199] The first counter may be used for RLF detection.

[0200] Note that the first counter may be the same as or different from the counter used for RLF detection in existing protocols (e.g., numConsecutiveDTX). For example, the first counter is numConsecutiveDTX.

[0201] Optionally, any one or more of the first data, the first control information, the first feedback information, the first feedback resource, the first counter, the first indication information, the PSFCH monitoring opportunity, and the RLF are associated with a unicast connection (e.g., one unicast connection or the first unicast connection) and / or an SL RRC connection (e.g., one SL RRC connection or the first SL RRC connection).

[0202] It may be understood that, optionally, the communication method provided in this embodiment of the present application may be performed for a unicast connection (e.g., one unicast connection), or the communication method provided in this embodiment of the present application may be performed for SL processes associated with a unicast connection (e.g., all SL processes).

[0203] In this embodiment of the present application, "receive" and "received" have different meanings. Specifically, "receive" means performing a receiving operation, and the result of "receive" can be "received" or "not received". "Not receiving" means not performing a receiving operation, and the result of "not receiving" is "not received". That is, "not receiving" includes two scenarios: one is that a receiving operation is performed but fails, and the other is that a receiving operation is not performed. A unified explanation is provided here, and the details will not be described again later.

[0204] Optionally, the first feedback information is transmitted on a first feedback resource, for example, the first feedback resource may be a PSFCH resource.

[0205] For example, the first feedback information in this embodiment of the present application may be ACK / NACK information.

[0206] For example, the first feedback information is an ACK indicating that the second user equipment has successfully received the first data.

[0207] For example, the first feedback information is a NACK indicating that the second user equipment failed to receive the first data.

[0208] Optionally, the first feedback information may be replaced by the PSFCH for indication.

[0209] In a possible implementation, initializing the first counter by the first user equipment includes initializing a count value of the first counter to 0 or a first value by the first user equipment. In this implementation, the initial value of the first counter is 0 or the first value, and the count value for triggering RLF is a preset threshold (e.g., a third threshold). It may be understood that RLF will be / is triggered when the count value of the first counter reaches (or is equal to or greater than) the preset threshold (e.g., the third threshold).

[0210] For example, the first value may be an integer, such as 1. This is not limited in the present application.

[0211] Note that the third threshold may be the same as or different from the threshold used for RLF detection in existing protocols (e.g., sl-maxNumConsecutiveDTX). For example, the third threshold is sl-maxNumConsecutiveDTX.

[0212] In another possible implementation, the first user equipment may further initialize the count value of the first counter to a preset threshold (e.g., the third threshold). In this implementation, the initial value of the first counter is the preset threshold (e.g., the third threshold), and the count value for triggering RLF is 0 or the first value. It may be understood that when the count value of the first counter reaches (or is less than) 0 or the first threshold, RLF will be / is triggered.

[0213] Optionally, leaving the count value of the first counter unchanged may include / be replaced with the first user equipment determining that the count value of the first counter is not changed or that the count value of the first counter is to be left unchanged.

[0214] In the communication method provided in this embodiment of the present application, when the first user equipment does not receive the first feedback information, the first user equipment initializes the first counter or leaves the count value of the first counter unchanged. The first feedback information is not received because the first user equipment does not receive the first feedback information, not because there is a problem with the radio link (e.g., SL). The first counter does not count cases where the first feedback information is not received because the first user equipment does not receive the first feedback information, and therefore the count value of the first counter does not erroneously / prematurely / accelerately reach the count value for triggering RLF. This reduces the possibility of false triggering of RLF, reduces communication delay, and improves / guarantees communication quality or reliability.

[0215] S603: When the first user equipment receives the first feedback information but fails to receive the first feedback information, the first user equipment increments or decrements the count value of the first counter by 1. In the above method, when the first user equipment receives but fails to receive the first feedback information, the first user equipment may fail to receive the first feedback information due to a problem in a radio link (e.g., SL). The first counter counts the cases when the first user equipment receives but fails to receive the first feedback information.

[0216] Optionally, step S603 may include / be replaced with: for a unicast connection, the first user equipment receives the first feedback information; and if the first user equipment fails to receive the first feedback information, the first user equipment increments or decrements the count value of the first counter by 1.

[0217] It should be noted that when the initial value of the first counter is 0 or the first value, and the count value that triggers RLF is a preset threshold (e.g., the third threshold), if the first user equipment receives the first feedback information but fails to receive the first feedback information, the first user equipment will increase the count value of the first counter by 1.

[0218] It should be noted that when the initial value of the first counter is a preset threshold (e.g., the third threshold), and the count value triggering RLF is 0 or the first value, if the first user equipment receives the first feedback information but fails to receive the first feedback information, the first user equipment decrements the count value of the first counter by 1.

[0219] Compared with the prior art, this method imposes a constraint on the increase or decrease of the count value of the first counter, so that the count value of the first counter does not erroneously / prematurely / too quickly reach the count value for triggering RLF, thereby avoiding erroneous triggering of RLF, reducing communication delay, and improving / ensuring communication quality or reliability.

[0220] It should be noted that the count value of the first counter may be increased by 1 or decreased by 1. In other words, the granularity / step size of the change in the count value of the first counter may be 1. Alternatively, the count value of the first counter may be increased by a or decreased by a, where a is a positive integer. In other words, the granularity / step size of the change in the count value of the first counter may be a. This is not limited in the present application. It may be understood that the first user equipment incrementing or decrementing the count value of the first counter by 1 may include / be replaced with the first user equipment incrementing or decrementing the count value of the first counter by a.

[0221] S604: When first feedback information is received by the first user equipment, the first user equipment initializes a first counter.

[0222] Optionally, step S604 may include / be replaced by, for a unicast connection, when first feedback information is received by the first user equipment, the first user equipment initializing a first counter.

[0223] Optionally, the present application further includes, when the count value of the first counter reaches (or is greater than) a third threshold, or the count value of the first counter reaches (or is less than) 0 or the first value, the first user equipment performs any one or more of the following: the first user equipment triggers / detects RLF; the MAC layer (or MAC entity, HARQ entity, or SL HARQ entity) of the first user equipment indicates to an upper layer (e.g., RRC layer) of the first user equipment that RLF has been detected; the first user equipment sends first indication information to a network device.

[0224] Optionally, the first user equipment triggering / detecting an RLF may include / be replaced with the first user equipment determining that an RLF has been triggered / detected.

[0225] The first indication information indicates that an RLF has been detected by the first user equipment, indicates that an RLF has occurred, or indicates that the SL failure is caused by an RLF.

[0226] For example, the first indication information indicates that an RLF has been detected by the first user equipment, that an RLF has occurred, or that the SL failure is caused by an RLF, for a first unicast connection or a first SL RRC connection.

[0227] For example, the first indication information may be included in sidelink user equipment information (SUI), which is not limited in the present application.

[0228] The first user equipment triggers an RLF and reports the RLF to a network device to indicate that a radio link (eg, SL) is abnormal or that the radio link (eg, SL) has failed.

[0229] Optionally, the application further includes the unicast connection being established or the third threshold / first value being configured or reconfigured, and the first user equipment initializing the first counter.

[0230] Optionally, the first user equipment not receiving the first feedback information includes the first user equipment not receiving the first feedback information if reception of the first feedback information conflicts with the first transmission.

[0231] In the above method, the first counter used for RLF detection does not count resource contention / transmission contention cases, so that the first counter can exclude other reasons that may cause the first feedback information not to be received by the first user equipment, and counts as many times as possible the number of times that the first user equipment fails to receive the first feedback information due to problems in the radio link (e.g., SL), so that the count value of the first counter does not erroneously / prematurely / too quickly reach the count value for triggering RLF, thereby avoiding erroneous triggering of RLF, reducing communication delay, and improving / ensuring communication quality or reliability.

[0232] In this embodiment of the present application, the first transmission is a separate transmission that is different from the reception of the first feedback information.

[0233] The first transmission may include a first transmission and / or a first reception.

[0234] For example, the first transmission may be a PSFCH transmission, an UL transmission, or an LTE SL transmission.

[0235] Optionally, the first user equipment not receiving the first feedback information when the reception of the first feedback information conflicts with the first transmission includes the first user equipment not receiving the first feedback information when the reception of the first feedback information conflicts with the first transmission and the priority of the reception of the first feedback information is equal to or lower than the priority of the first transmission, or the reception of the first feedback information conflicts with the first transmission and the priority of the reception of the first feedback information is equal to or lower than the priority of the first transmission.

[0236] Optionally, the priority of receiving the first feedback information being equal to or lower than the priority of the first transmission may be understood / replaced as the reception of the first feedback information not being prioritized.

[0237] Optionally, the priority of receiving the first feedback information being less than or equal to the priority of the first transmission may include the first user equipment determining that the priority of receiving the first feedback information is less than or equal to the priority of the first transmission.

[0238] Optionally, not prioritizing reception of the first feedback information may include the first user equipment determining that reception of the first feedback information is not prioritized.

[0239] In the above method, when a resource contention / transmission contention occurs and the priority of receiving the first feedback information is low, the first feedback information is not received because the first user equipment performs the first transmission with a high priority but does not receive the first feedback information, not because there is a problem with the radio link. The first counter does not count the cases where the first feedback information is not received because the first user equipment does not receive the first feedback information, and therefore the count value of the first counter does not erroneously / prematurely / fastly reach the count value for triggering RLF. This avoids erroneous triggering of RLF, reduces communication delay, and improves / guarantees communication quality or reliability.

[0240] In this embodiment of the present application, for the definition and comparison of reception or transmission priority, please refer to the section in the introduction of this specification regarding the reception of PSFCH competing with another transmission / reception, and the details will not be described again here.

[0241] For example, referring to Fig. 2, Fig. 7 shows that the existing protocol and the communication method provided in the embodiment of the present application are used in the RLF detection process. The initial values ​​of the first counter and the counter of the existing protocol are both 0, and the count values ​​for triggering RLF are both 3. For details of the process of RLF detection in the existing protocol, please refer to the content described in Fig. 2. The details will not be described again here. The following describes the process in which the communication method provided in the embodiment of the present application is used for RLF detection.

[0242] During the first PSFCH monitoring opportunity, the transmitting UE does not receive the PSFCH because the reception of the PSFCH conflicts with another transmission and does not have priority. The count value of the first counter remains unchanged and remains at the initial value 0.

[0243] In the second PSFCH monitoring opportunity, the transmitting UE receives the PSFCH but fails to receive the PSFCH, and the count value of the first counter is increased by one to become one.

[0244] At the third PSFCH monitoring opportunity, the PSFCH is received by the transmitting UE, and the first counter is initialized to 0.

[0245] In the fourth PSFCH monitoring opportunity, the transmitting UE receives the PSFCH but fails to receive the PSFCH, and the count value of the first counter is increased by one to become one.

[0246] At the fifth PSFCH monitoring opportunity, the transmitting UE receives the PSFCH but fails to receive the PSFCH, and the count value of the first counter is increased by one to become two.

[0247] At the sixth PSFCH monitoring opportunity, the receiving of the PSFCH conflicts with another transmission of the PSFCH, and the receiving of the PSFCH does not have priority, so the transmitting UE does not receive the PSFCH. The count value of the first counter remains unchanged and remains 2.

[0248] At the seventh PSFCH monitoring opportunity, the PSFCH is received by the transmitting UE, and the first counter is initialized to 0.

[0249] At the eighth PSFCH monitoring opportunity, the receiving of the PSFCH conflicts with another transmission of the PSFCH, and the receiving of the PSFCH does not have priority, so the transmitting UE does not receive the PSFCH, and the count value of the first counter remains unchanged and remains 0.

[0250] At the ninth PSFCH monitoring opportunity, the receiving of the PSFCH conflicts with another transmission of the PSFCH, and the receiving of the PSFCH does not have priority, so the transmitting UE does not receive the PSFCH, and the count value of the first counter remains unchanged and remains 0.

[0251] At the tenth PSFCH monitoring opportunity, the PSFCH is received by the transmitting UE, and the first counter is initialized to 0.

[0252] In the 11th PSFCH monitoring opportunity, the PSFCH is received by the transmitting UE, and the count value of the first counter remains unchanged and remains 0. In other words, the first counter is initialized to 0.

[0253] It can be understood that Figure 7 only shows PSFCH monitoring opportunities associated with the first unicast connection or the RRC connection of the first SL, and that reception of PSFCHs associated with other unicast connections or multicast communications is not relevant to this solution and is not shown in the figure.

[0254] It should be noted that Figure 7 shows only 11 PSFCH monitoring occasions as an example. The actual PSFCH monitoring occasions may be continuous or discontinuous in the time domain, or alternatively, different PSFCH monitoring occasions may overlap in the time domain. This is not limited in this embodiment of the present application.

[0255] From the above analysis, it can be seen that, compared with the prior art, the first user equipment in the communication method provided in this embodiment of the present application will not erroneously trigger RLF in the sixth PSFCH monitoring opportunity, and therefore, the communication delay can be reduced, and the communication quality or reliability can be improved / guaranteed.

[0256] In a possible implementation (Implementation 1), the present application further includes: when the signal quality between the first user equipment and the second user equipment is greater than or equal to a first threshold, after performing step S601, the first user equipment performs any one or more of steps S602, S603, and S604.

[0257] Optionally, the signal quality between the first user equipment and the second user equipment being greater than or equal to the first threshold may include the first user equipment determining that the signal quality between the first user equipment and the second user equipment is greater than or equal to the first threshold.

[0258] It should be noted that the order of "determining that the signal quality between the first user equipment and the second user equipment is greater than or equal to the first threshold" and step S601 is not limited in the present application.

[0259] For example, signal quality between a first user equipment and a second user equipment being equal to or greater than a first threshold may be understood as signal quality between the first user equipment and the second user equipment being good.

[0260] It can be understood that when the signal quality is good, it indicates that the radio link is normal, and the first counter used for RLF detection does not count the cases where the first feedback information is not received because the first user equipment does not receive the first feedback information, thereby avoiding false triggering of RLF, reducing communication delay, and improving / ensuring communication quality or reliability.

[0261] In this embodiment of the present application, the signal quality between the first user equipment and the second user equipment may be determined based on reference signal received power (RSRP), reference signal received quality (RSRQ), channel state information (CSI), SL-CSI, or sounding reference signal (SRS), etc. This is not limited in the present application. In another possible implementation (Implementation 2), the present application further includes: the signal quality between the first user equipment and the second user equipment is equal to or less than a second threshold. As shown in FIG. 6b, after performing step S601, the first user equipment performs step S605 and / or step S606.

[0262] Optionally, the signal quality between the first user equipment and the second user equipment being less than or equal to the second threshold may include the first user equipment determining that the signal quality between the first user equipment and the second user equipment is less than or equal to the second threshold.

[0263] It should be noted that the order of "the first user equipment determining that the signal quality between the first user equipment and the second user equipment is equal to or less than the second threshold" and step S601 is not limited in this application.

[0264] For example, the signal quality between the first user equipment and the second user equipment being below a second threshold may be understood as the signal quality between the first user equipment and the second user equipment being poor.

[0265] S605: If the first user equipment fails to receive the first feedback information, the first user equipment increases the count value of the first counter by one.

[0266] Optionally, step S605 may include / be replaced with, for a unicast connection, if the first user equipment fails to receive the first feedback information, the first user equipment increments a count value of the first counter by 1.

[0267] The first user equipment failing to receive the first feedback information includes the first user equipment not receiving the first feedback information, and / or the first user equipment receiving the first feedback information but the first user equipment failing to receive the first feedback information.

[0268] S606: When the first feedback information is received by the first user equipment, the first user equipment initializes a first counter or keeps the count value of the first counter unchanged.

[0269] Optionally, step S606 may include / be replaced by, for a unicast connection, when first feedback information is received by the first user equipment, the first user equipment initializing a first counter or leaving the count value of the first counter unchanged.

[0270] It can be understood that when the signal quality is poor, it indicates that there may be an exception in the radio link. In this case, the first counter used for RLF detection counts the cases where the first feedback information is not received because the first user equipment does not receive the first feedback information, so that RLF can be triggered more quickly, and further, the unicast connection can be restored / re-established as soon as possible, thereby reducing communication delay.

[0271] It should be noted that the first threshold and the second threshold may be the same or different, which is not a limitation in the present application.

[0272] It should be noted that Implementation 1 and Implementation 2 may be used as separate embodiments (or Implementation 2 may not depend on Implementation 1, or Implementation 2 may not depend on steps S602, S603, and S604), or Implementation 1 and Implementation 2 may be combined with each other (or any one or more of steps S602, S603, and S604 may be combined with steps S605 and / or S606). This is not a limitation in the present invention.

[0273] 8 shows another communication method according to an embodiment of the present application. The communication method includes the following steps:

[0274] S801: A first user equipment transmits first data to a second user equipment via an SL.

[0275] For the description of step S801, please refer to the related description of step S601, and the details will not be described again here.

[0276] After step S801, the first user equipment may perform steps S802 and / or S803.

[0277] S802: If the first user equipment does not receive the first feedback information, the first user equipment increments or decrements the count value of the second counter by one.

[0278] The first feedback information indicates whether the second user equipment has successfully received the first data.

[0279] The content associated with the first feedback information is shown in FIG. a and Figure 6b Please refer to the associated description of the embodiment in. The details will not be described again here.

[0280] The second counter is configured to count the number of times that feedback information is not received by the first user equipment consecutively.

[0281] Optionally, step 80 2 may include / be replaced with, for a unicast connection, if the first user equipment does not receive the first feedback information, the first user equipment increments or decrements the count value of the second counter by 1.

[0282] Optionally, any one or more of the first data, the first control information, the first feedback information, the first feedback resource, the feedback information, the second counter, the second indication information, the third indication information, and the PSFCH monitoring opportunity are associated with a unicast connection (e.g., one unicast connection or the first unicast connection) and / or an SL RRC connection (e.g., one SL RRC connection or the first SL RRC connection).

[0283] It may be understood that, optionally, the communication method provided in this embodiment of the present application may be performed for a unicast connection (e.g., one unicast connection), or the communication method provided in this embodiment of the present application may be performed for SL processes associated with a unicast connection (e.g., all SL processes).

[0284] It should be noted that the count value of the second counter may be increased by 1 or decreased by 1. In other words, the granularity / step size of the change in the count value of the second counter may be 1. Alternatively, the count value of the second counter may be increased by b or decreased by b, where b is a positive integer. In other words, the granularity / step size of the change in the count value of the second counter may be b. This is not limited in the present application. It may be understood that the first user equipment incrementing or decrementing the count value of the second counter by 1 may include / be replaced with the first user equipment incrementing or decrementing the count value of the second counter by b.

[0285] It should be noted that the second counter may be used independently, or may be used together with the first counter provided in this embodiment of the present application. Alternatively, the second counter may be used together with the counter in the existing protocol shown in Figure 2. This is not limited in the present application.

[0286] S803: When the first user equipment receives first feedback information, the first user equipment initializes a second counter.

[0287] Optionally, step 80 3 may include / be replaced with, for a unicast connection, if the first user equipment receives the first feedback information, the first user equipment initializes a second counter.

[0288] In a possible implementation, initializing the second counter by the first user equipment includes initializing a count value of the second counter by the first user equipment to 0 or a second value. In this implementation, the initial value of the second counter is 0 or the second value, and the count value of any one or more of triggering RLF, triggering transmission of the second indication information and / or the third indication information, and triggering resource reselection is a preset threshold (e.g., a fourth threshold). It may be understood that when the count value of the second counter reaches (or is equal to or greater than) the preset threshold (e.g., the fourth threshold), any one or more of RLF, transmission of the second indication information and / or the third indication information, and resource reselection will be triggered.

[0289] For example, the second value may be an integer, such as 1. This is not limited in the present application.

[0290] For example, resource reselection may include SL resource reselection.

[0291] In another possible implementation, the first user equipment may further initialize a count value of the second counter to a preset threshold (e.g., a fourth threshold). In this implementation, the initial value of the second counter is the preset threshold (e.g., the fourth threshold), and the count value of any one or more of triggering RLF, triggering transmission of the second indication information and / or the third indication information, and triggering resource reselection is 0 or a second value. It may be understood that when the count value of the second counter reaches (or is less than) 0 or the second value, any one or more of RLF, transmission of the second indication information and / or the third indication information, and resource reselection will be triggered.

[0292] It should be noted that when the initial value of the second counter is 0 or the second value, and any one or more of the count values ​​of triggering RLF, triggering transmission of the second indication information and / or the third indication information, and triggering resource reselection is a preset threshold (e.g., the fourth threshold), if the first user equipment receives the first feedback information but fails to receive the first feedback information, the first user equipment increases the count value of the second counter by 1.

[0293] It should be noted that when the initial value of the second counter is a preset threshold (e.g., the fourth threshold), and any one or more of the count values ​​of triggering RLF, triggering transmission of the second indication information and / or the third indication information, and triggering resource reselection is 0 or the second value, if the first user equipment receives the first feedback information but fails to receive the first feedback information, the first user equipment decrements the count value of the second counter by 1.

[0294] Optionally, the application further includes the unicast connection being established or the fourth threshold / second value being configured or reconfigured, and the first user equipment initializing a second counter.

[0295] Optionally, the present application further includes, when the count value of the second counter reaches (or is greater than) a fourth threshold, or the count value of the second counter reaches (or is less than) 0 or the second value, the first user equipment performs any one or more of the following: the first user equipment triggers / detects RLF; the MAC layer (or MAC entity, HARQ entity, or SL HARQ entity) of the first user equipment indicates to an upper layer (e.g., RRC layer) of the first user equipment that RLF has been detected; the first user equipment sends the second indication information and / or the third indication information to a network device; or alternatively, the first user equipment triggers resource reselection.

[0296] Optionally, the first user equipment triggering / detecting an RLF may include / be replaced with the first user equipment determining that an RLF has been triggered / detected.

[0297] The second indication information indicates that an RLF has been detected by the first user equipment, indicates that an RLF has occurred, or indicates that the SL failure is caused by an RLF.

[0298] The third indication information indicates that the count value of the second counter has reached a fourth threshold (or is equal to or greater than the fourth threshold), or that the count value of the second counter has reached 0 or the second value (or is less than or equal to the fourth threshold), indicates that the number of times that feedback information is not consecutively received by the first user equipment has reached a preset threshold (e.g., the fourth threshold), or indicates that the number of times that reception of feedback information consecutively conflicts with another transmission has reached a preset threshold (e.g., the fourth threshold).

[0299] For example, the second indication information indicates that an RLF has been detected by the first user equipment for the first unicast connection or the first SL RRC connection, that an RLF has occurred, or that the SL failure is caused by an RLF.

[0300] For example, the third indication information indicates that, for the first unicast connection or the RRC connection of the first SL, the count value of the second counter has reached a fourth threshold (or is equal to or greater than the fourth threshold), or the count value of the second counter has reached 0 or the second value (or is less than or equal to the fourth threshold), indicates that the number of times that feedback information is not consecutively received by the first user equipment has reached a predetermined threshold (e.g., the fourth threshold), or indicates that the number of times that reception of feedback information consecutively conflicts with another transmission has reached a predetermined threshold (e.g., the fourth threshold).

[0301] It should be noted that the second indication information may be the same as or different from the first indication information, which is not limited in this application.

[0302] Optionally, the second indication information may further indicate a reason for triggering / detecting the RLF. For example, the reason may include: the number of times that feedback information is not continuously received by the first user equipment reaches a preset threshold (e.g., a fourth threshold); the number of times that reception of feedback information continuously conflicts with another transmission reaches a preset threshold (e.g., a fourth threshold); the count value of the second counter reaches the fourth threshold (or is equal to or greater than the fourth threshold); or the count value of the second counter reaches 0 or a second value (or is less than or equal to the fourth threshold).

[0303] For example, the second indication information and / or the third indication information may be included in sidelink user equipment information (SUI), which is not limited in the present application.

[0304] In another communication method provided in this embodiment of the present application, the first user equipment may report the second indication information (e.g., the reason for triggering / detecting RLF) and / or the third indication information to the network device, indicating to the network that there is a high probability of current resource contention / transmission contention (or that the amount of current resource contention / transmission contention has reached a certain threshold), so that the network device can adjust some parameters accordingly, thereby reducing the possibility of resource contention / transmission contention, improving communication quality, reducing communication delay, and ensuring communication reliability.

[0305] In another communication method provided in this embodiment of the present application, when an RLF is triggered / detected by a first user equipment, the first user equipment may use a corresponding policy, such as restoring a unicast connection or re-establishing a unicast connection, thereby improving communication quality, reducing communication delay, and ensuring communication reliability.

[0306] In another communication method provided in this embodiment of the present application, a first user equipment triggers resource reselection, and thus the first user equipment can reselect resources, which may reduce the possibility of resource contention / transmission contention, improve communication quality, reduce communication delay, and ensure communication reliability.

[0307] It should be noted that in the present application, different embodiments may be combined with each other, some contents / steps in different embodiments may be combined with each other, or all contents in different embodiments may be combined with each other.

[0308] Please note that in this application, for ease of use, the same terms / contents will not be repeatedly described in different embodiments. Unless otherwise specified, the same terms / contents may be used in different embodiments.

[0309] The first user equipment in the above embodiment may use the architecture of the communication device 40 shown in Figure 4, so that the operation of the first user equipment in the above embodiment may be performed by the processor 401 in the communication device 40 shown in Figure 4 by calling the application program code stored in the memory 403 to instruct the first user equipment to perform the operation, which is not limited in this embodiment.

[0310] Alternatively, the operations of the first user equipment in the above steps S601 and S602 and steps S801 and S802 may be performed by the processor 510 in the mobile terminal 50 shown in Figure 5 by calling application program code stored in memory (including the internal memory 521 or an external memory connected to the external memory interface 520) to instruct the mobile terminal to perform the operations, which is not limited in this embodiment.

[0311] In the above embodiments, it may be understood that the methods and / or steps implemented by the first user equipment may be implemented by components (e.g., chips or circuits) that may be used in the first user equipment.

[0312] The above description mainly describes the solutions provided in the embodiments of the present application from the perspective of a first user equipment. Accordingly, the embodiments of the present application further provide a communication device configured to implement the above-described method. The communication device may be the first user equipment in the above-described method embodiments, or a device including the above-described first user equipment, or a component that can be used in the first user equipment. To implement the above-described functions, the communication device may include a hardware structure and / or software modules for performing each function. Those skilled in the art will easily recognize that the present application can be implemented by hardware or a combination of hardware and computer software by combining the example units and algorithm steps described in the embodiments disclosed herein. Whether the functions are implemented by hardware or hardware driven by computer software depends on the specific application and design constraints of the technical solution. Those skilled in the art may use different methods to implement the described functions for each specific application, but such implementation should not be considered to go beyond the scope of the present application.

[0313] In the embodiments of the present application, the communication device may be divided into functional modules based on the above-described method embodiments. For example, each functional module may be obtained through division based on the corresponding function, or two or more functions may be integrated into one processing module. The integrated module may be implemented in the form of hardware or in the form of a software function module. It should be noted that in the embodiments of the present application, the module division is an example and is merely a logical function division. In actual implementation, other division methods may be used.

[0314] 9 is a schematic diagram of the structure of a communication device 90. The communication device 90 includes a transceiver module 901 and a processing module 902. The transceiver module 901 may be referred to as a transceiver unit and is configured to implement transceiver functionality. For example, the transceiver module 901 may be a transceiver circuit, a transceiver unit, a transceiver device, or a communication interface.

[0315] For example, the communication device 90 is the first user equipment in the above method embodiment. In this case, the transceiver module 901 is configured to transmit first data to a second user equipment via a side link (SL). The processing module 902 is configured to initialize a first counter or leave the count value of the first counter unchanged if first feedback information is not received. The first feedback information indicates whether the second user equipment has successfully received the first data. The first counter is used for RLF detection.

[0316] In one possible implementation, the transceiver module 901 is further configured to receive first feedback information, and the processing module 902 increases the count value of the first counter by 1 if the first feedback information is not received.

[0317] In a possible implementation, failing to receive the first feedback information includes not receiving the first feedback information if reception of the first feedback information conflicts with the first transmission.

[0318] In a possible implementation, not receiving the first feedback information includes receiving the first feedback information conflicts with the first transmission, the priority of receiving the first feedback information is less than or equal to the priority of the first transmission, and the first feedback information is not received.

[0319] In a possible implementation, configuring the processing module 902 to initialize the first counter includes configuring the processing module 902 to initialize a count value of the first counter to zero.

[0320] In a possible implementation, the processing module 902 is further configured to increase a count value of the first counter by 1 when the signal quality between the first user equipment and the second user equipment is below a second threshold and the first feedback information fails to be received.

[0321] In a possible implementation, the transceiver module 901 is further configured to send first indication information to the network device when the count value of the first counter is greater than or equal to a third threshold, the first indication information indicating that an RLF has been detected by the first user equipment.

[0322] All related contents of the steps in the above method embodiments can be cited in the functional descriptions of the corresponding functional modules, and the details will not be described again here.

[0323] In this embodiment, the communication device 90 is provided in the form of functional modules obtained by division in an integrated manner, where a module may be an ASIC, a circuit, a processor executing one or more software or firmware programs, a memory, an integrated logic circuit, and / or another component capable of providing the above-mentioned functionality.

[0324] Those skilled in the art may understand that when the communication device 90 is the first user equipment in the above method embodiment, in a simple embodiment, the communication device 90 may be in the form shown in FIG.

[0325] For example, the processor 401 or 407 in the first user equipment shown in Figure 4 may invoke computer-executable instructions stored in the memory 403, so that the first user equipment can perform the communication method in the above method embodiment. Specifically, the functions / implementation processes of the transceiver module 901 and the processing module 902 in Figure 9 may be implemented by the processor 401 or 407 in the first user equipment shown in Figure 4 by invoking computer-executable instructions stored in memory. Alternatively, the functions / implementation processes of the processing module 902 in Figure 9 may be implemented by the processor 401 or 407 in the first user equipment shown in Figure 4 by invoking computer-executable instructions stored in memory, and the functions / implementation processes of the transceiver module 901 in Figure 9 may be implemented by the communication interface 404 shown in Figure 4.

[0326] Alternatively, those skilled in the art will appreciate that if the communication device 90 is the first user equipment in the above method embodiment and the first user equipment is a mobile terminal, in a simple embodiment the communication device 90 may be in the form of the mobile terminal 50 shown in FIG. 5 .

[0327] For example, the processor 510 in the mobile terminal 50 shown in FIG. 5 may invoke computer-executable instructions stored in memory (including the internal memory 521 or an external memory connected to the external memory interface 520), thereby allowing the mobile terminal 50 to perform the communication method in the above method embodiment. Specifically, the functions / implementation processes of the transceiver module 901 and the processing module 902 of FIG. 9 may be implemented by the processor 510 in the mobile terminal 50 shown in FIG. 5 by invoking computer-executable instructions stored in memory. Alternatively, the functions / implementation processes of the processing module 902 of FIG. 9 may be implemented by the processor 510 in the mobile terminal 50 shown in FIG. 5 by invoking computer-executable instructions stored in memory, and the functions / implementation processes of the transceiver module 901 of FIG. 9 may be implemented by the wireless communication module 550 shown in FIG. 5.

[0328] The communication device 90 provided in this embodiment can implement the above-mentioned communication method. Therefore, please refer to the above-mentioned method embodiment for the technical effects that can be achieved by the communication device 90. The details will not be described again here.

[0329] It should be noted that one or more of the above modules or units may be implemented by software, hardware, or a combination thereof. When any one of the above modules or units is implemented by software, the software exists in the form of computer program instructions and is stored in a memory. A processor may be configured to execute the program instructions and implement the above method steps. The processor may be incorporated in a system-on-a-chip (SoC) or an ASIC, or may be an independent semiconductor chip. In addition to a core configured to execute software instructions to perform an operation or process, the processor may further include necessary hardware accelerators, such as a field programmable gate array (FPGA), a programmable logic device (PLD), or a logic circuit that implements dedicated logic operations.

[0330] When the above modules or units are implemented using hardware, the hardware may be any one or any combination of a CPU, microprocessor, digital signal processing (DSP) chip, microcontroller unit (MCU), artificial intelligence processor, ASIC, SoC, FPGA, PLD, dedicated digital circuitry, hardware accelerator, or non-integrated discrete device, and the hardware may or may not execute software necessary to perform the above method steps.

[0331] Optionally, the embodiments of the present application further provide a chip system. The chip system includes at least one processor and an interface. The at least one processor is coupled to a memory via the interface. When the at least one processor executes a computer program or instructions in the memory, a method according to any one of the above method embodiments is performed. In a possible implementation, the communication device further includes a memory. Optionally, the chip system may include a chip, or may include a chip and another discrete component. This is not particularly limited in the embodiments of the present application.

[0332] All or part of the above embodiments may be implemented using software, hardware, firmware, or any combination thereof. When a software program is used to implement the embodiments, the embodiments may be fully or partially implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the procedures or functions according to the embodiments of the present application are generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions may be transmitted from a website, computer, server, or data center to another website, computer, server, or data center in a wired (e.g., coaxial cable, optical fiber, or digital subscriber line (DSL)) or wireless (e.g., infrared, radio, or microwave) manner. The computer-readable storage medium may be any available medium that can be accessed by a computer, or may be a data storage device such as a server or data center that consolidates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, or magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives (SSDs)).

[0333] Although the present application is described with reference to embodiments, in the course of implementing the claimed application, those skilled in the art may understand and implement other variations of the disclosed embodiments by studying the accompanying drawings, the disclosed content, and the appended claims. In the claims, "comprising" does not exclude other components or steps, and "a" or "one" does not exclude a plurality. A single processor or other unit may implement several functions recited in the claims. Although some actions are recited in mutually different dependent claims, this does not mean that these actions cannot be combined to produce better effects.

[0334] Although the present application has been described with reference to particular features and embodiments thereof, the present application Example of It is apparent that various modifications and combinations can be made thereto without departing from the scope thereof. Accordingly, the specification and accompanying drawings are merely exemplary descriptions of the present application as defined by the appended claims, and any and all modifications, variations, combinations or equivalents that fall within the scope of the present application are to be considered. Those skilled in the art will readily appreciate that the present application Example of It is apparent that various modifications and variations can be made to the present application without departing from the scope thereof. The present application is intended to cover these modifications and variations as long as they fall within the scope of protection defined by the appended claims and their equivalent technologies.

Claims

1. 1. A communication method comprising: transmitting, by a first user equipment, first data to a second user equipment via a side link (SL); initializing a first counter or leaving the count value of the first counter unchanged, by the first user equipment, if the first user equipment does not receive first feedback information; Including, the first feedback information indicates whether the second user equipment has successfully received the first data, and the first counter is used for radio link failure (RLF) detection; wherein the first user equipment not receiving first feedback information comprises the first user equipment not performing an operation of receiving the first feedback information in a first physical sidelink feedback channel (PSFCH) monitoring occasion if reception of the first feedback information conflicts with a first transmission.

2. 2. The method of claim 1, further comprising: if the first user equipment receives the first feedback information but fails to receive the first feedback information, increasing the count value of the first counter by 1, by the first user equipment.

3. When reception of the first feedback information conflicts with the first transmission, the first user equipment not receiving the first feedback information 2. The method of claim 1, wherein the reception of the first feedback information competes with the first transmission, and the priority of the reception of the first feedback information is less than or equal to the priority of the first transmission.

4. 4. The method of claim 1, wherein initializing a first counter by the first user equipment comprises initializing the count value of the first counter to 0 by the first user equipment.

5. The method of claim 1 , wherein a signal quality between the first user equipment and the second user equipment is greater than or equal to a first threshold.

6. 4. The method according to claim 1, further comprising: incrementing, by the first user equipment, the count value of the first counter by one when a signal quality between the first user equipment and the second user equipment is equal to or lower than a second threshold and the first user equipment fails to receive the first feedback information.

7. 4. The method according to claim 1, wherein the first feedback information is transmitted on the Physical Sidelink Feedback Channel (PSFCH).

8. 4. The method according to claim 1, further comprising: if the count value of the first counter is equal to or greater than a third threshold, transmitting, by the first user equipment, first indication information to a network device, the first indication information indicating that a radio link failure (RLF) has been detected by the first user equipment.

9. A communication device, said communication device comprising at least one unit adapted to perform the method according to any one of claims 1 to 3.

10. 4. A communications device comprising a memory and a processor coupled to the memory, wherein the memory is configured to store a program, and the processor is configured to execute the program stored in the memory, such that when the communications device is operational, the processor executes the program, enabling the communications device to perform the method of any one of claims 1 to 3.

11. 4. A computer-readable storage medium storing a computer program, the computer program being executed by a computer to enable the computer to perform the method of any one of claims 1 to 3.

12. A chip including a processor, the processor coupled to a memory, the memory configured to store a program or instructions, the program or instructions being executed by the processor enabling the chip to perform the method of any one of claims 1 to 3.

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