Sidelink channel access processing method, device, and network side device

Abstract

The present disclosure provides a channel access processing method, an apparatus and a network side device for sidelink, which relate to the field of communication technology. The channel access processing method for sidelink applied to a first terminal includes the steps of: the first terminal performing resource selection to determine a first target resource; and performing a first type channel access procedure for at least a part of the first target resource to determine whether a channel is idle and a channel occupation time (COT).

Description

[Technical field]

[0001] [CROSS REFERENCE TO RELATED APPLICATIONS] This disclosure claims priority to China Patent Application No. 202210470995.2, filed in China on April 28, 2022, the entire contents of which are incorporated herein by reference. The present disclosure relates to the field of communications technology, and in particular to a channel access processing method, device, and network side equipment for sidelink. [Background technology]

[0002] 3GPP (registered trademark) (3rd Generation Partnership Project) has introduced SL-U (Sidelink Operation on Unlicensed Spectrum) into the related technology. Compared with the communication mechanism of licensed band, the equipment operating in unlicensed band can use the band without license, so it is necessary to introduce LBT (Listen Before Talk) mechanism to avoid mutual interference between different systems.

[0003] In the related art, SL-U is still unclear in terms of resource selection, resource transmission, relationship with LBT, and processing process. Although some designs of NR-U (New Radio Unlicensed) operating in unlicensed bands can be reused, it is necessary to consider the impact of the distributed resource allocation mechanism adopted in Sidelink on LBT. For example, due to the poor joint scheduling of the base station, the transmission between different terminals becomes discontinuous, interrupting the continuous occupation of the channel. Therefore, it is necessary to design a new processing process and method of LBT taking into account the relevant characteristics of Sidelink. In short, the LBT mechanism for SL-U is still unclear, and the relevant processing process needs to be normalized and defined in the standardization process. Summary of the Invention [Problem to be solved by the invention]

[0004] The objective of the present disclosure is to provide a channel access processing method, device, and network side equipment for sidelink, thereby avoiding the problem of discontinuous transmission between terminals, which interrupts continuous channel occupation, and clarifying the LBT processing mechanism of SL-U. [Means for solving the problem]

[0005] To achieve the above object, an embodiment of the present disclosure provides a channel access processing method for sidelink applied to a first terminal, the method including: performing resource selection by the first terminal to determine first target resources; and performing a first type channel access procedure for at least some of the first target resources to determine whether a channel is idle and a channel occupancy time (COT).

[0006] To achieve the above object, an embodiment of the present disclosure further provides a sidelink channel access processing method applied to a second terminal, the method including: receiving, by the second terminal, first control information transmitted by a first terminal, the first control information including information on a channel occupation time (COT) determined by the first terminal; and transmitting information based on the first control information.

[0007] To achieve the above object, an embodiment of the present disclosure further provides a channel access processing device for sidelink, including: a first processing module configured to cause a first terminal to perform resource selection to determine first target resources; and a second processing module configured to perform a first type channel access procedure for at least some of the first target resources, and determine whether a channel is idle and a channel occupation time (COT).

[0008] To achieve the above object, an embodiment of the present disclosure further provides a channel access processing device for sidelink, the device including: a third processing module configured for a second terminal to receive first control information transmitted by a first terminal; and a fourth processing module configured for performing information transmission based on the first control information, where the first control information includes information regarding a channel occupation time (COT) determined by the first terminal.

[0009] To achieve the above object, an embodiment of the present disclosure provides a network side device, which includes a transceiver, a processor, a memory, and a program or instruction stored in the memory and executable by the processor, and when the processor executes the program or instruction, realizes the channel access method for sidelink described in any of the above embodiments.

[0010] To achieve the above object, an embodiment of the present disclosure provides a readable storage medium having stored thereon a program or instruction that, when executed by a processor, realizes the channel access method for sidelink according to any of the above embodiments. Effect of the Invention

[0011] The technical effects of the above technical solutions of the present disclosure are as follows:

[0012] In an embodiment of the present disclosure, the first terminal performs resource selection to determine a first target resource, and performs a first type channel access procedure for at least a part of the first target resource to determine whether the channel is idle and a channel occupation time (COT). The present disclosure complements the sidelink channel access processing process, clarifies the specific operation for the terminal to perform channel access, and further ensures that the terminal maintains continuous occupation of the sidelink during channel access, thereby reducing the probability of transmission failure caused by access of other systems. [Brief description of the drawings]

[0013] [Figure 1] 4 is a flowchart of a processing method applied to a first terminal according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a schematic diagram of a first specific embodiment according to an embodiment of the present disclosure. [Diagram 3] FIG. 2 is a schematic diagram of a second specific embodiment according to an embodiment of the present disclosure. [Figure 4] FIG. 13 is a schematic diagram of a third specific embodiment according to an embodiment of the present disclosure. [Diagram 5] FIG. 13 is a schematic diagram of a fourth specific embodiment according to the present disclosure. [Figure 6] FIG. 13 is a schematic diagram of a fifth specific embodiment according to the present disclosure. [Figure 7] 11 is a flowchart of a processing method applied to a second terminal according to an embodiment of the present disclosure. [Figure 8] FIG. 13 is a schematic diagram of a sixth specific embodiment according to the present disclosure. [Figure 9] FIG. 13 is a schematic diagram of a seventh specific embodiment according to the embodiment of the present disclosure. [Figure 10] FIG. 1 is a schematic diagram of a module of a processing device according to an embodiment of the present disclosure. [Figure 11] FIG. 2 is a second schematic diagram of a module of a processing device according to an embodiment of the present disclosure. [Figure 12] FIG. 2 is a structural diagram of a mobile terminal according to an embodiment of the present disclosure. [Figure 13] FIG. 2 is a structural diagram of a network side device according to an embodiment of the present disclosure. [Figure 14] FIG. 13 is a schematic diagram of sending a placeholder message according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] In order to make the technical problems, technical solutions and advantages that the present disclosure aims to solve more clear, the following detailed description will be given with reference to the drawings and examples.

[0015] In addition, in various embodiments of the present disclosure, the magnitude of the numbers of the following processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and does not limit the implementation process of the embodiments of the present disclosure.

[0016] It should be noted that in this specification, the terms "system" and "network" are often used interchangeably.

[0017] The terms "first", "second", and the like in the specification and claims of the present disclosure are intended to distinguish between similar objects and are not intended to describe a particular order or sequence. It should be noted that such data may be interchanged where appropriate so that the embodiments of the present application may be performed in an order other than that shown or described herein. In addition, the objects distinguished by "first" and "second" are generally similar and do not limit the number of objects, for example, the first object may be one or more. In addition, "and / or" in the specification and claims indicates at least one of the objects before and after, and the character " / " generally indicates that the related objects before and after are in an "or" relationship.

[0018] Before describing the embodiments of the present disclosure, we first explain some concepts that will be used in the following description.

[0019] 1. Unlicensed bands Unlicensed spectrum can be used free of charge without application and can be used by any organization or individual. For example, commonly used technologies such as WiFI (wireless network communication technology) and Bluetooth (registered trademark) all use unlicensed bands. In order to avoid interference between different systems, it is necessary to avoid interference with other systems as much as possible when using unlicensed bands, so LBT technology is introduced to monitor the channel before accessing it and only access the channel if the system is confirmed to be idle.

[0020] 2. LBT (Listen Before Talk) Mechanism A terminal operating in an unlicensed band needs to perform channel detection before accessing a channel, and can only access the channel to transmit a service waiting for transmission when it detects that the channel is idle. The channel detection method includes the following steps:

[0021] (1) Type 1 channel access method As shown in the table below, the terminal first determines the priority of channel access, and then determines the relevant parameters of channel access. The process is as follows: Steps 1 to 6.

[0022] In Step 1, a counter N is set to Nint, where Nint is a random number uniformly distributed between 0 and CWp. Next, Step 4 is executed.

[0023] In Step 2, if N>0, the terminal subtracts 1 from the counter, i.e., N=N-1.

[0024] In Step 3, a monitoring slot with a time length of Tsl (Tsl indicates an LBT monitoring slot, and has a length of 9 μs) is detected for the channel. If the monitoring slot is idle, Step 4 is executed; otherwise, Step 5 is executed.

[0025] In Step 4, if N=0, end the channel access; otherwise, execute Step 2.

[0026] In Step 5, detection is performed on the channel at a time interval of time length Td (where Td = 16 + mp × 9 μs), and the detection result for that time interval is that at least one monitoring slot is occupied or all monitoring slots are idle.

[0027] In Step 6, if the channel monitoring result shows that all monitoring slots within the Td time period are idle, execute Step 4; otherwise, execute Step 5.

[0028] After the channel access procedure is completed, the terminal mcot,p After determining the channel, the terminal transmits the pending service using the channel. The channel occupancy time (COT) of the terminal is the maximum channel occupancy time corresponding to the channel access priority. mcot,p In order to ensure that different users of the same system can occupy the system continuously and prevent other systems from accessing and seizing the channel in the middle, the terminal may share the COT with other terminals after acquiring the COT, which is called COT sharing. Here, the channel access priority classes are shown in the following table.

[0029] [Table 1]

[0030] Here, C.W. min,p is the minimum contention window size, CW max,p is the maximum contention window size, T mcot,p is the maximum channel occupancy time, CW p may be referred to as the set of allowed contention window sizes.

[0031] (2) Type 2 channel access method After a terminal obtains the COT shared by another terminal, the terminal may evaluate the channel using the Type 2 method before transmission. The Type 2 channel access method is a channel access method based on a fixed channel monitoring length, and includes the following three methods:

[0032] 1) Type 2A channel access A terminal shall monitor the channel for at least 25 μs before beginning to transmit, and shall transmit only after successful channel monitoring.

[0033] 2) Type 2B channel access A terminal monitors the channel for 16 μs before starting to transmit, and transmits after successful channel monitoring.

[0034] 3) Type2C channel access The terminal transmits directly without channel monitoring, where the gap between the start of the current transmission and the end of the previous transmission is less than or equal to 16 μs, and the length of the transmission does not exceed 584 μs.

[0035] In the following, "Type 1 channel access" refers to the Type 1 channel access method, and is indicated by Type 1 LBT. "Type 2 channel access" refers to the Type 2 channel access method, and is indicated by Type 2 LBT.

[0036] As shown in FIG. 1 , an optional embodiment of the present disclosure provides a channel access processing method for a sidelink applied to a first terminal, the method including steps 100 and 200.

[0037] In step 100, the first terminal performs resource selection to determine a first target resource.

[0038] In addition, the resource selection performed by the first terminal includes, but is not limited to, a process for continuous resources, a process for determining the number of resource selections, a process for non-contiguous resources, etc. The resource selection on the first terminal side determines a first target resource with enhanced resource selection.

[0039] In step 200, a first type channel access procedure is performed for at least a portion of the first target resource to determine whether the channel is idle and the channel occupancy time COT.

[0040] Here, the first type of channel access refers to a channel access scheme that performs random backoff using a contention window (CW) of variable size and determines the size of the CW based on a channel access priority class.

[0041] In this embodiment, the COT determined in step 200 is not necessarily that of the first terminal, and may be shared with the second terminal, and the COT here indicates only the COT determined by the first terminal. The purpose of determining whether the channel is idle in step 200 is to avoid mutual interference problems caused by different systems transmitting simultaneously as much as possible. The present disclosure has supplemented the flow of sidelink channel access processing.

[0042] Optionally, the step 100 may include steps 110 to 130.

[0043] In step 110, a time to trigger resource selection is determined.

[0044] In step 120, a resource selection window is determined based on the time that triggers the resource selection.

[0045] In step 130, a first target resource is determined based on the resource selection window.

[0046] Here, the first time interval T1 between the start time of the resource selection window and the time of triggering resource selection is determined by the transmission processing delay, the resource selection processing delay of the first terminal, and the minimum time length for performing the first type channel access procedure.

[0047] In this embodiment, before determining the first target resource, the range of T1 at the front edge (start time of the resource selection window) of the resource selection window determined by the first terminal is limited. When the first terminal performs resource selection, it determines the time n at which the resource selection is triggered and determines the time range [n+T1, n+T2] of the resource selection window. (n+T1) indicates the front edge of the resource selection window, and (n+T2) indicates the back edge of the resource selection window. That is, the first terminal determines the first target resource within the range [n+T1, n+T2] based on the sensing result.

[0048] Here, the first time interval T1 is determined based on the start time of the resource selection window and the time to trigger the resource selection. In order to determine the first time interval T1, the transmission processing delay T proc,1 , resource selection processing delay T proc,1-A , the minimum time length T minLBT At least one of the following factors must be taken into consideration. The minimum time length for executing the first type channel access procedure is the minimum time length for the type 1 LBT to be executed this time (or in the future). proc,1-A is a parameter newly defined in this disclosure, that is, the first terminal is (n+T proc,1-A ) to complete the resource selection, and determine the time-frequency location of the resource at this time.

[0049] In addition, the transmission processing delay T proc,1 is parameter information determined in the sidelink resource selection process, and is the same as the determination method in the related art protocol, so the description is omitted here.

[0050] Specifically, the first time interval T1 is: the first time interval T1 is greater than or equal to zero; the first time interval T1 is less than or equal to the transmission processing delay; The first time interval T1 is longer than the minimum time length; The first time interval T1 is greater than the sum of the minimum time length and the resource selection processing delay.

[0051] In this embodiment, the first time interval T1 is expressed as a formula: 0≦T1 or T1≦T proc,1 , or T1>T minLBT , or T1>T minLBT +T proc,1-A It is expressed as:

[0052] The first time interval T1 is further defined as T1≧T minLBT , or T1 ≥ T minLBT +T proc,1-A Satisfy at least one of the following:

[0053] Specifically, in this case, the end time of the resource selection window is: The end time of the resource selection window is within a range smaller than the packet delay budget (PDB) of the data packet; and the end time of the resource selection window is within a first predetermined time range after the resource selection is triggered.

[0054] The first predetermined time is a time limit for the terminal to realize one resource selection.

[0055] In addition, the embodiment of the present disclosure may further include determining a back edge (n+T2) parameter of the resource selection window, where the value and definition of T2 is the minimum value T2 allowed for T2. min and Remaining Packet Transmission Delay (PDB).

[0056] The present disclosure is advantageous in achieving enhanced resource selection in Sidelink resource selection by determining the first time interval T1.

[0057] Optionally, the first target resource satisfies that the number of the first target resources is N+M resources.

[0058] Here, N is the number of transmission resources required for transmitting the transmission block TB, and M is the number of added candidate transmission resources, where N and M are integers of 1 or more.

[0059] In addition, by adding M candidate transmission resources, the transmission resources of the first terminal are prevented from being wasted.

[0060] Specifically, the value of M is: A value set by a higher layer, or A value that is predefined, preset, or set by the protocol; or A value determined based on the first parameter information.

[0061] Specifically, the first parameter information is: Channel access priority; The priority of data, Channel Busy Ratio (CBR) and The value of N; The length of time that the first terminal has performed the first type channel access procedure in the past, i.e., the length of time of the history Type 1 LBT of the first terminal; Channel Occupancy Ratio (CR) and Maximum Channel Occupancy (CR limit ) and at least one of.

[0062] In this embodiment, the present disclosure considers that the LBT time is constant, and when the channel is busy, the time length of Type1 LBT is large, so that the LBT end time is later than the time of some transmission resources, and the expired transmission resources are discarded after the LBT ends. If extra candidate resources are not added, there is a risk that the number of transmissions available due to LBT will be reduced. In view of this, the number of resources selected when the first terminal performs resource selection is set to N+M, where N is the number of transmission resources required for transmitting a transport block (TB), and M is the number of candidate transmission resources added separately. Here, M is a value set or preset by an upper layer, or determined by the first parameter information.

[0063] Here, N is the number of resources for transmission set by the current resource selection or pre-configured. For example, if one TB requires 32 transmissions and the current resource selection only supports 4 of them, then N=4, not 32.

[0064] As shown in FIG. 2, in the first embodiment, assuming that the number of transmissions corresponding to one TB of the first terminal is 4, some resources may be unavailable due to the uncertainty of the time length of Type1 LBT. Therefore, the terminal needs to select additional M candidate resources when performing resource selection. Here, if M=2, the terminal needs to select a total of six resources that can be used for transmission. After resource selection, the terminal performs Type1 LBT. Since the time of the end of LBT is located after the initially selected second candidate resource, the previous two initially selected resources are invalidated and cannot be used for transmission. After that, the terminal takes the initially selected third resource as the actual initial transmission resource, and the initially selected fourth resource as the actual first retransmission resource, and so on.

[0065] Optionally, the first target resource determined in step 100 is: In the available resources, resources that are continuous in the time domain, Among available resources, resources that are contiguous in time domain with resources reserved by other terminals; Among the available resources, resources that are within one maximum channel occupancy time, and The available resources include at least one of the resources that are within the same maximum channel occupancy time as the resources reserved by other terminals.

[0066] In this embodiment, when the first terminal performs resource selection, it determines a corresponding channel access priority based on the data priority, and further determines a corresponding maximum channel occupancy time (COT). In order to ensure maximum utilization of the COT determined by Type 1 LBT and ensure continuous occupancy of the channel by Sidelink, performing enhancement based on random resource selection may include at least one of the following aspects:

[0067] In aspect 1-1, the terminal preferentially selects contiguous resources in the time domain from available resources (mainly for blind retransmission, and does not need to consider Hybrid Automatic Repeat reQuest (HARQ) feedback time).

[0068] In aspect 1-2, a terminal preferentially selects, from available resources, resources that are contiguous in the time domain with resources reserved by other terminals.

[0069] In the aspects 1-3, the transmission resource selected by the terminal from the available resources is within one maximum channel occupancy time.

[0070] In aspects 1-4, the transmission resource selected by the terminal from the available resources is within one maximum channel occupancy time of the same resource as the resource reserved by another terminal.

[0071] As shown in Fig. 3, in the second embodiment, if the transmission of the first terminal needs to occupy one subchannel, four transmissions are required, and the numbers are the indexes of available resources. According to the above resource selection method, the terminal performs random resource selection, which can be {1, 6, 17, 21}, or {1, 5, 10, 14}, etc.

[0072] In aspect 1-1, consecutive resources are selected in the time domain, and since {1, 6, 17, 21} does not satisfy the requirement in this case, the first terminal can select consecutive resources in the time domain, such as {1, 5, 10, 14} or {4, 9, 13, 18}.

[0073] In the example 1-2, a resource that is consecutive in sequence to the resource reserved by another terminal is selected. Among the candidate resources {5, 14, 19, 23} and the candidate resources {5, 19, 23, 28}, the terminal preferentially selects {5, 14, 19, 23}. This is to ensure that the transmission of the terminal is consecutive in the time domain with the transmission of the other terminals, and ensure continuous occupancy of the channel by the Sidelink system.

[0074] In the embodiment 1-3, assume that the time of COT is 4 slots. In this case, for resource {5, 10, 14, 19} and resource {5, 14, 23, 33}, the terminal preferentially selects {5, 10, 14, 19}. This is because the corresponding resource is within one COT time. For transmission within one COT, the terminal only needs to perform Type 2 channel access procedure, which is relatively simple and the channel access procedure is faster.

[0075] In the embodiment 1-4, it is assumed that the COT time is 5 slots. In this case, for resource {10, 14, 28, 33} and resource {10, 14, 23, 28}, the terminal preferentially selects the latter. This is because the latter ensures that the occupation of the system by Sidelink is continuous in time and within one COT time as a whole.

[0076] As described above, the present disclosure maximizes the use of the COT determined by Type 1 LBT, ensures reinforcement based on random resource selection, and ensures continuous occupancy of the channel by the sidelink.

[0077] Optionally, the first target resource determined in step 100 further includes resources among the available resources that satisfy the second condition and are non-contiguous in the time domain.

[0078] Here, the second condition is that a second time interval between two adjacent transmissions is greater than a first predetermined threshold, and the first predetermined threshold is a value set by a higher layer or a value predefined, pre-set or set by a protocol.

[0079] Here, the first predetermined threshold is preferably a minimum time length of the type 1 channel access procedure.

[0080] In this embodiment, if the available resources are non-contiguous in the time domain, and one transmission is located within the shared COT, but the subsequent transmission is not located within the COT time, that is, Type 1 LBT still needs to be performed before the subsequent transmission, the aspect for this case is to ensure that the interval between two transmissions is greater than a first predetermined threshold to ensure that the terminal has time to perform Type 1 LBT. Here, the first predetermined threshold is the minimum time to perform Type 1 LBT, i.e., N init ×T sl T sl represents an LBT monitoring slot, which is 9 μs long.init 0 to CW p The present disclosure is capable of securing sufficient LBT time in advance when continuity cannot be realized in available resources, thereby realizing the strengthening of the first target resource.

[0081] It should be noted that the above available resources refer to the remaining resources after unavailable resources are removed from the resource selection window based on the sensing result.

[0082] Optionally, in step 200, performing a first type channel access procedure on at least a portion of the first target resources may include the following steps:

[0083] In step 210, a first candidate time for the first class channel access procedure to start and / or a second candidate time for the first class channel access procedure to start is determined.

[0084] In step 220, an LBT start time for performing the first type channel access procedure is determined based on the first candidate time and / or the second candidate time.

[0085] In step 230, a first type channel access procedure is performed for at least a portion of the first target resources based on the LBT start time.

[0086] In this embodiment, the first terminal can determine the time at which the first terminal starts the LBT, i.e., the LBT start time, by determining the first candidate time and / or the second candidate time, thereby ensuring that different users of the same system continuously occupy the system and avoiding other systems from accessing and seizing the channel in the middle.

[0087] Specifically, the step 220 may include a step 221, a step 222, or a step 223.

[0088] In step 221, if the second candidate time is equal to or later than the first candidate time, it is determined that the LBT start time is equal to or later than the first candidate time and equal to or earlier than the second candidate time.

[0089] In this embodiment, the first terminal further determines the time when the first terminal actually starts the LBT (i.e., the LBT start time) based on the determined first candidate time and the determined second candidate time. In step 221, it is determined that the LBT start time is between the first candidate time and the second candidate time, i.e., the first candidate time≦LBT start time≦second candidate time. Specifically, the LBT start time may be the earliest time of the LBT, or the latest time of the LBT, or a time between the two, and can be realized by the first terminal.

[0090] In step 222, if the second candidate time is earlier than the first candidate time, it is determined that the LBT start time is equal to or later than the first candidate time.

[0091] In this embodiment, if the second candidate time is earlier than the first candidate time, only the first candidate time is valid. The first candidate time is the time when the determination of the time-frequency location of the resource is completed, that is, the first terminal can perform LBT only after determining the time-frequency location of the resource.

[0092] Alternatively, the step 220 includes a step 223 .

[0093] In step 223, it is determined that the LBT start time is equal to or later than the first candidate time.

[0094] In this embodiment, only the first candidate time is determined, and the LBT start time is ensured to be later than or equal to the first candidate time. The first candidate time is the time when the determination of the time-frequency location of the resource is completed, that is, the first terminal can perform the LBT only after determining the time-frequency location of the resource.

[0095] Determining the first candidate time determining a first start time at which the first terminal is triggered to perform resource selection and a processing delay for the first terminal to perform resource selection; and determining the first candidate time according to Equation 1: A1=B1+C1.

[0096] Here, A1 denotes the first candidate time, B1 denotes the first start time, and C1 denotes a processing delay for the first terminal to perform resource selection.

[0097] Here, C1 may indicate a transmission processing delay of the first terminal.

[0098] In this embodiment, the first terminal determines a first start time for performing resource selection based on the first target resource, i.e., at a time n for triggering resource selection, i.e., at time n, the sensing result is determined and a transmission process is started. The present disclosure further provides a processing delay T proc,1-A (In the related art, the transmission processing delay T proc,1 where only T proc,1 indicates the total time for resource selection and transmission-related operations such as transmission processing), and the first candidate time = n + T proc,1-A The completion time of resource selection is determined by Equation 1 expressed as follows, and the time-frequency location of the resource is determined at this time.

[0099] Here, the first candidate time is preferably the earliest time of the LBT, and is similar to the time for determining the resource time-frequency position.

[0100] Optionally, determining the second candidate time further comprises: determining, based on the first target resource, a time when a resource corresponding to a first type channel access procedure is present among the first target resources, and a first time length for performing the first type channel access procedure; and determining the second candidate time according to Equation 2: A2=B2-C2. Here, the first time length indicates the minimum time of Type 1 LBT.

[0101] Alternatively, determining the second candidate time may include: determining a time length required for a transmission block TB of said first target resource, a latest time of a resource selection window of said first target resource, and said first time length; and determining the second candidate time according to Equation 3: A2=B3-C2-D1.

[0102] In addition, in the formula 2, the second candidate time = T LBT待ちリソース - The minimum value of Type1 LBT time length. Here, T LBT待ちリソース is the time where the resource is located, i.e., the time domain position of the resource when performing Type 1 LBT, and the minimum value of the Type 1 LBT time length is N init ×T sl Here, N init , T sl is consistent with the introduction above.

[0103] Here, A2 denotes the second candidate time, B2 denotes the time where the resource is located, C2 denotes the first time length, B3 denotes the latest time in the resource selection window, and D1 denotes the time length required for the transmission block TB. Note that B3 may be the latest time allowed for service transmission, that is, the packet arrival time plus the packet transmission delay.

[0104] In addition, in Equation 3, the second candidate time=the back edge of the resource selection window (or the latest time allowed for service transmission)−the time length required for TB−the minimum value of the Type 1 LBT time length.

[0105] The second candidate time may be understood as the latest time at which the LBT is started.

[0106] Note that the second candidate time may be before the first candidate time, i.e., (T LBT待ちリソース - Type 1 LBT time length (minimum) < (n+T proc,1-A ). In this case, only the earliest time is valid, i.e. (n+T proc,1-A ) is valid because the first terminal can perform LBT only after determining the time-frequency location of the resource.

[0107] As shown in FIG. 4, in the third embodiment, the first terminal starts resource selection and other transmission processes at time n. proc,1-A Assuming that the resource selection is completed and the location of the selected resource is determined at time (T 初期送信 -N init ×T sl In this case, the time period during which each Tsl needs to monitor the channel even if it is idle is N init ×T sl Therefore, the latest time that LBT can start is (T 初期送信 -N init ×T sl ) The initial transmission resource later than this time cannot be used, of course. In practice, the time at which the first terminal starts the LBT may be located between the earliest and latest times.

[0108] Optionally, after performing the first type channel access procedure in step 200 , the method further includes step 240 and step 250 .

[0109] In step 240, an end time at which execution of the first type channel access procedure ends and a first time of a resource waiting to be transmitted that is closest to the end time are determined.

[0110] In step 250, the pending resources are transmitted based on the end time and the first time.

[0111] The present disclosure determines whether or not placeholder information has been transmitted between the end time and the first time by determining the end time and the first time, thereby avoiding a situation in which channel resources are always reserved due to the terminal being unable to receive second terminal scheduling, thereby improving efficiency of channel usage.

[0112] Alternatively, the step 250 may include a step 251 or may include a step 252 and a step 253 .

[0113] In step 251, if the end time is equal to the first time or the distance between the end time and the first time is less than or equal to a second predetermined threshold, the pending resource is transmitted directly.

[0114] In step 252, if the end time is before the first time, a first target interval between the end time and the first time is determined.

[0115] In step 253, a determination is made to transmit the pending resource based on the first target interval.

[0116] In this embodiment, after the LBT (which may be Type 1 LBT or Type 2 LBT) of the first terminal is finished, determine the end time when the execution of the first type channel access procedure is finished, that is, determine the time X1 when the channel becomes idle. Furthermore, determine the first time M1 of the resource waiting for transmission that is closest to the end of the LBT. In this case, before transmitting to M1, the behavior of the first terminal may include at least one of the following:

[0117] In step 251, if the position where the LBT ends is exactly at the first time M1 of the resources waiting to be transmitted or the interval between M1 and the position where the LBT ends is less than or equal to a second predetermined threshold, the first terminal directly transmits the resources waiting to be transmitted. The role of the second predetermined threshold is to determine whether placeholder information needs to be transmitted in the interval between M1 and the position where the LBT ends. For example, if the interval between M1 and the position where the LBT ends is less than 16 μs, it can be directly transmitted. Here, the second predetermined threshold is a value set by an upper layer, or a value predefined, pre-set or set by a protocol.

[0118] In steps 252 to 253, if there is a first target interval between the M1 and the time when the LBT ends, it is determined to transmit the pending resources based on the first target interval.

[0119] Specifically, before step 253, the method may include a step of sending the first placeholder information in any one of the following three manners:

[0120] In a first manner, if the first target interval is equal to or greater than a first time threshold, it is determined to transmit first placeholder information before the first time.

[0121] In the first scheme, it is ensured that the placeholder information is transmitted only when the interval is sufficiently large, and the placeholder information is not transmitted if the interval is small. If the first target interval is larger than (or equal to or greater than) a first time threshold, it is determined to transmit the first placeholder information to perform channel occupancy on the channel before the first time, and if the first target interval is equal to or smaller than (or less than) the first time threshold, the placeholder information is not transmitted.

[0122] In a second manner, if the first target interval is equal to or less than a second time threshold, it is determined to transmit the first placeholder information before the first time.

[0123] In the second method, it is ensured that the time for transmitting the placeholder information is not too long so as not to be unfair to other systems. If the interval between them is smaller than the second time threshold (or equal to or smaller than the second time threshold), it is determined to transmit the first placeholder information before the first time to perform channel occupancy on the channel, and if the interval between them is equal to or larger than the second time threshold (or larger than the second time threshold), it does not transmit the placeholder information and performs Type 2 channel access before transmitting.

[0124] In a third manner, if the first target interval is between the second time threshold and the first time threshold, it is determined to transmit the first placeholder information before the first time.

[0125] A third scheme is a combination of the second scheme and the first scheme, where the second time threshold is less than the first time threshold.

[0126] wherein a time length for transmitting the first placeholder information is equal to or less than a third predetermined threshold, and the first time threshold, the second time threshold and the third predetermined threshold are all values ​​set by a higher layer or values ​​predefined, pre-set or set by a protocol.

[0127] In addition, the time length for transmitting the first placeholder information may be set or preset by a higher layer. Also, the first time threshold may be related to the time required for Type 2 LBT. The time length for transmitting the first placeholder information may be related to the location of the transmission waiting resource of the first terminal and / or the time required for Type 2 LBT and / or the service priority and / or the channel access priority.

[0128] It should be noted that the above first threshold or second threshold is only for illustrating several different situations, and does not actually define the first threshold and the second threshold, but only indicates that the transmission of placeholder information is permitted before transmission, and the transmission time length of the placeholder information needs to be equal to or less than a (pre-)set threshold, where the (pre-)set threshold corresponding to the time length of transmitting the placeholder information may be related to a service priority or a channel access priority.

[0129] As shown in FIG. 5, in the fourth embodiment, the first terminal performs a physical sidelink control channel (PSCCH) / physical sidelink shared channel (PSSCH) transmission after completing the Type 1 LBT. If the interval between subsequent transmissions is smaller than the set delay threshold and larger than the Type 2 LBT time, the terminal transmits placeholder information for a predetermined time to ensure that the interval between the next transmissions meets the time length of the Type 2 LBT, thereby avoiding access by other systems during this period. The reason for defining the delay threshold is to prevent the time length of the placeholder information transmitted by the terminal from being too long, which is unfair to other systems. That is, the placeholder information can be transmitted only under a predetermined condition, and the time length of the placeholder information is not too long.

[0130] Optionally, the method further includes step 300 .

[0131] In step 300, the first terminal transmits first control information to a second terminal.

[0132] The first control information includes information related to the COT determined by the first terminal.

[0133] The steps 100 to 200 are a process in which the first terminal performs Type 1 LBT based on a first target resource to determine a COT, and this process is related only to the first terminal. The steps 100 to 300 are a processing process in which the first terminal performs Type 1 LBT based on a first target resource to determine a COT, and further shares information related to the COT determined by the first terminal with a second terminal.

[0134] In addition, sharing the COT is not a required feature, and it does not have to be shared with other user equipment (User Equipment, UE), that is, the COT may be used only by the first terminal (steps 100 to 200). The sharing of the COT can also realize the process of "first terminal's LBT + first terminal shares the determined COT + second terminal receives the COT" (steps 100 to 300).

[0135] In step 300, after the first terminal executes Type 1 LBT, the first terminal can transmit information about the COT determined by the first terminal to a second terminal. Here, the first control information includes at least one of Remaining COT, time-frequency location of resources waiting for transmission of the first terminal, LBT subband information, ID of the first terminal, ID of the terminal that is scheduled to receive the shared COT information, priority of services waiting for transmission of the first terminal, COT placeholder information determined by the first terminal, Channel Busy Ratio (CBR) information measured by the first terminal, time-frequency range of transmission resources recommended for use by other terminals (similar to UE-to-UE cooperative processing), time-frequency range of transmission resources not recommended for use by other terminals, channel access priority, etc.

[0136] The scene of step 300 may include at least one of unicast, multicast with connection, multicast without connection, and broadcast.

[0137] Optionally, step 300 includes the first terminal transmitting the first control information to a second terminal if a first condition is met.

[0138] The first condition is: The remaining time of the COT is equal to or greater than a first preset threshold value; a time length for performing the first type channel access procedure is equal to or less than a second preset threshold; The number of remaining transmissions of the first terminal is equal to or less than a preset third threshold; The first terminal receives solicitation information transmitted by the second terminal to the first terminal (the solicitation information is used to indicate that the first terminal expects to receive the first control information transmitted by the first terminal); The first terminal has a service to transmit to the second terminal; Configuration or pre-configuration by higher layers supports COT sharing; The first terminal supports execution of COT sharing; The value of the service priority of the first terminal is less than (or equal to) a predetermined service priority threshold; The value of the channel access priority of the first terminal is less than (or equal to) a channel access priority threshold; and The time-frequency resource occupancy rate of the first terminal is smaller than (or equal to or smaller than) a value of a time-frequency resource ratio in COT set or preset by a higher layer.

[0139] The preset first threshold, preset second threshold, preset third threshold, predetermined service priority threshold, and intra-COT time-frequency resource ratio are all values ​​set by a higher layer or preset by a protocol, etc. The first threshold and the second threshold may be 3 to 5 ms. The number of times of the third threshold may be 1, 2, 3, 4, etc., and is not limited thereto. The preset service priority threshold may be 1 to 8. The intra-COT time-frequency resource ratio may be 20%, etc.

[0140] Before step 300, the method may further include step 310.

[0141] In step 310, the maximum decoding processing delay is determined.

[0142] In this embodiment, before step 300, the first terminal determines a maximum decoding processing delay from a predetermined protocol, which is equal to or greater than the decoding processing delay of the second terminal, to ensure continuous occupancy of the channel and avoid access by other systems.

[0143] Optionally, the first terminal is configured to, within the maximum decoding processing delay: At least one of the following may be performed: the first terminal performs a service transmission to the second terminal; and the first terminal transmits second placeholder information to the second terminal, where a delay of the second placeholder information is less than or equal to a fourth predetermined threshold.

[0144] It is noted that the fourth predetermined threshold value is related to a service priority or a channel access priority.

[0145] The first terminal occupies a channel by performing continuous transmission within the maximum decoding processing delay, the continuous transmission including at least one of a PSCCH (Physical Sidelink Control Channel) / PSSCH (Physical Sidelink Shared Channel) transmission and transmitting the second placeholder information.

[0146] Here, the time length for transmitting the second placeholder information is T proc,0 -T PSCCH / PSSCH where T proc,0 is the maximum decoding processing delay, and T PSCCH / PSSCH is the time when the first terminal transmits the PSCCH / PSSCH, and T PSCCH / PSSCH may be 0.

[0147] In addition, the first terminal determines the COT and then shares the COT with the second terminal, but considering the decoding processing time of the second terminal, it is necessary to perform additional processing to ensure continuous occupancy of the channel and prevent access by other systems. In addition, the first terminal may continuously transmit PSCCH / PSSCH, and since the channel is already occupied during this time, TPSCCH / PSSCH is further subtracted.

[0148] After determining the COT in step 200, the method may further include steps 410-430.

[0149] In step 410, a retransmission time for the first terminal is determined.

[0150] In step 420, if the retransmission time falls within the COT, a second type of channel access procedure is performed for retransmission of at least a portion of the first target resource.

[0151] In step 430, if the retransmission time is outside the COT, a first type channel access procedure is performed for retransmission of at least a portion of the first target resource.

[0152] Here, the second type of channel access refers to a channel access that performs only LBT based on a determined interval.

[0153] In this embodiment, if the subsequent transmission of the first terminal, i.e., the retransmission time of the first terminal, is within the valid range of the COT, the type of Type2 LBT is determined according to the position and required time of the transmission, and the transmission process is performed after determining that the channel is idle. Here, the above-mentioned COT may be the COT determined by the first terminal itself, or the COT received and shared by the second terminal, but the COT here only indicates the COT determined by the first terminal. If the retransmission time of the first terminal is not within the valid range of the COT, the channel is monitored again according to Type1 LBT before the subsequent transmission, i.e., the first type channel access procedure is performed for the retransmission of at least a part of the first target resource.

[0154] In step 200, when performing a first type channel access procedure for at least a portion of the first target resources, if second control information transmitted by a second terminal to the first terminal is received, the method may further include step 500.

[0155] In step 500, if a second condition is met, it is determined to terminate the first type channel access procedure, and performs a second type channel access procedure for at least a portion of the first target resources based on the second control information. Here, the second control information includes information regarding a COT determined by the second terminal, and the second type of channel access indicates performing channel access based only on an LBT of the determined interval.

[0156] The information regarding the COT determined by the second terminal is similar to the information regarding the COT determined by the first terminal described above, and therefore will not be described in detail here.

[0157] Needless to say, the method further includes the steps of directly determining to terminate the first-type channel access procedure, and performing a second-type channel access procedure on at least a portion of the first target resources.

[0158] In this embodiment, when the first terminal receives related information of the COT shared by the second terminal in the process of performing Type1 LBT, the first terminal may terminate Type1 LBT and transmit using Type2 LBT during the remaining time of the COT shared by the second terminal according to the second control information, that is, may preferentially use the COT shared by other terminals. In other words, it is the process of "determining to terminate the first type channel access procedure and performing a second type channel access procedure for at least a part of the first target resources" defined in step 500.

[0159] Needless to say, the priority of the COT determined by the first terminal itself is higher than the priority of the COT received and shared by the second terminal, that is, the first terminal uses the COT determined by itself preferentially.

[0160] Specifically, the second condition is: The service priority of the first terminal is equal to or lower than the service priority of the second terminal; the channel access priority of the first terminal is lower than (or is lower than) the channel access priority of the second terminal; the remaining time of the COT of the second terminal is greater than (or equal to) a third time threshold.

[0161] Here, the third time threshold is a value set by a higher layer, or a value predefined, pre-set or set by a protocol.

[0162] The second type of channel access refers to performing channel access based only on the LBT of the determined interval.

[0163] In this embodiment, the second condition determined by the first terminal based on its own terminal related information (such as service priority, channel access priority, etc.) and / or the received second control information (including information related to the COT determined by the second terminal, i.e., service priority, channel access priority, Remaining COT, etc.) is: If the service priority of the first terminal is higher than (or equal to) the service priority of the terminal sharing the COT, the Type 1 LBT of the first terminal is performed as is, otherwise, the Type 1 LBT of the first terminal is terminated and Type 2 LBT is performed using the COT shared by the second terminal for transmission; If the channel access priority of the first terminal is higher than (or equal to) the channel access priority of the terminal sharing the COT, the Type 1 LBT of the first terminal is performed as is; otherwise, the Type 1 LBT of the first terminal is terminated, and Type 2 LBT is performed using the COT shared by the second terminal for transmission; If the Remaining COT of the terminal that shared the COT is smaller than (or equal to or less than) the third time threshold, the Type 1 LBT of the first terminal is performed as is, and if not, the Type 1 LBT of the own terminal is terminated and Type 2 LBT is performed and transmitted using the COT shared by the second terminal. Here, the third time threshold is a value set by a higher layer, or a value predefined, pre-set or set by a protocol.

[0164] Step 500 and the second condition of the present disclosure specify a process for how a first terminal should process when it receives a COT shared by another terminal (second terminal) when performing Type 1 LBT, thereby complementing the processing mechanism of the first terminal.

[0165] As shown in FIG. 6, FIG. 6 illustrates the priority relationship between Type1 LBT and Type2 LBT. In the fifth embodiment, a first terminal performs Type1 LBT for initial transmission, and the start time is m1. In the execution process, if the first terminal receives a COT shared by a second terminal at time m2 shown in FIG. 6, and the initial transmission and retransmission resources of the subsequent transmission are located within the COT time period shared by the second terminal, the terminal can terminate Type1 LBT. Since the initial transmission and retransmission resources belong to the shared COT of the second terminal, the first terminal can perform Type2 LBT before transmission, thereby gaining faster access to the channel.

[0166] As described above, the first terminal of the present disclosure can realize resource selection, execution of Type 1 LBT, determination of COT, reinforcement processing before initial transmission, initial transmission, sharing of COT, reinforcement processing after sharing of COT, LBT for retransmission, and retransmission. The present disclosure complements the sidelink channel access processing procedure, clarifies the specific behavior of the terminal performing channel access, and further ensures that continuous occupancy of the sidelink is maintained during channel access, thereby reducing the risk of transmission failure due to access of other systems.

[0167] As shown in FIG. 7 , an embodiment of the present disclosure further provides a channel access processing method for sidelink applied to a second terminal, the method including step 400 and step 500.

[0168] In step 400, the second terminal receives first control information transmitted by a first terminal, the first control information including information related to a COT determined by the first terminal.

[0169] Here, the information about the COT determined by the first terminal is consistent with the information introduced above, and will not be described in detail here.

[0170] In step 500, information transmission is performed based on the first control information.

[0171] In this embodiment, after the second terminal receives the information about the COT determined by the first terminal, its own resource selection process or transmission process may be affected to some extent, so that steps 400 to 500 further complement the processing process of the second terminal, and maintain the continuous occupation of the channel by the Sidelink system as much as possible.

[0172] Specifically, the supplement to the resource selection process of the second terminal may include the following two methods. In method 1, the terminal determines a resource selection window based on the received COT. A specific determination method may be to set the intersection of the COT and the resource selection window determined by the terminal as the resource selection window to be finally used. In method 2, the terminal determines a final available resource set (or updates the available resource set) based on the received COT. In a specific method, all available resources within the COT time period in the available resource set determined by the terminal are set as a first available resource set, and the second terminal first selects resources from the first available resource set, and if the resources in the first available resource set do not meet the transmission requirement, it returns to the complete available resource set determined by the terminal to select resources.

[0173] Optionally, after the step 400 and if the second terminal has already determined a second target resource, the step 500 includes a step 510 and a step 520 .

[0174] In step 510, the remaining time of the COT is determined based on the first control information.

[0175] In step 520, if the transmission time of the second target resource determined by the second terminal at the first terminal is within the remaining time of the COT, the second terminal performs a second type channel access procedure to transmit information.

[0176] In this embodiment, if the second terminal has already determined the second target resource, it only considers the effect of the received COT on the transmission. If the transmission of the second terminal is within the remaining time (Remaining COT) of the received COT, the Type 2 channel access procedure performed by the second terminal is relatively simpler and the access process is faster.

[0177] Specifically, the start time at which the second terminal performs the second type channel access procedure is one time unit before the time unit in which the second target resource is located.

[0178] Note that an LBT is performed in the previous time unit, and a transmission / reception switching time is guaranteed after the LBT. Placeholder information may be further transmitted after the transmission / reception switching time. Here, the transmission of placeholder information is not essential, and for example, if the time at which the transmission / reception switching (TX / RX switching) is completed is located exactly at the back edge of the previous slot, the second terminal may directly perform transmission in the current time unit. The time unit may be a slot, a set of consecutive symbols, etc. In particular, the start time at which the second terminal performs the type-2 channel access procedure may be located at the last symbol of the previous time unit.

[0179] Please refer to FIG. 8. In FIG. 8, CPE is an extension of a cyclic prefix (CP), and may be understood as a method of transmitting placeholder information. In the sixth embodiment, the time unit is a slot, and each slot includes 14 symbols. If the current subcarrier interval is 15 kHz, the length of one symbol is about 71.4 μs. A terminal can transmit PSCCH / PSSCH in slot n and execute Type2-A LBT, and the terminal starts LBT at a certain point in symbol #13 of the previous slot. Here, the selection of the start time needs to ensure that the LBT and the transmission / reception switching (TX / RX switching) time are completed before the transmission slot n.

[0180] In Scheme 1, after the receiving / transmitting switchover is completed, the terminal can transmit placeholder information to perform channel occupation, thereby ensuring that the placeholder information and the actual transmission are continuous in time.

[0181] In method 2, after the transmit / receive switch is completed, if the interval between the next slot is greater than a certain threshold, the terminal can transmit placeholder information to perform channel occupation, thereby ensuring that the placeholder information and the actual transmission are continuous in time.

[0182] Here, the last symbol of the previous slot is determined as the start time of Type2 LBT, that is, the start time at which the second terminal starts to execute the type-2 channel access procedure.

[0183] Alternatively, the start time at which the second terminal performs the second type channel access procedure is the time unit in which the second target resource is located.

[0184] In this embodiment, the start time of the second terminal performing the second type channel access procedure is the time unit where the second target resource is located. That is, the terminal performs LBT in the time unit (which can be understood as a slot) where the LBT waiting resource is located, prepares a transmit-receive switchover time before transmitting, and then overlaps and maps the whole or part of the content of the second symbol to the remaining part of the symbol where the LBT is located. In particular, the start time of the LBT may be located in the first symbol occupied by the current PSCCH / PSSCH transmission.

[0185] As shown in Fig. 9, in the seventh embodiment, the terminal can transmit PSCCH / PSSCH in slot n and execute Type2-A LBT. The terminal needs to start Type2 LBT from the start position of the first symbol in slot n, reserve a transmission / reception switching time after the LBT is completed, and then map some content of the second symbol in the remaining part of the first symbol in an overlapping manner.

[0186] Here, the first symbol of the current slot is determined as the start time of Type2 LBT, that is, the start time when the second terminal performs the second type channel access procedure.

[0187] In addition, in the present disclosure, the granularity of resources in the frequency domain may be subchannels, IRBs, non-contiguous physical resources, etc.

[0188] If the second terminal has not determined a second target resource after step 400, step 500 includes: determining a remaining time of the COT based on the first control information; The second terminal performs resource selection to determine a second target resource based on the remaining time of the COT; and transmitting information based on the second target resource and the first control information.

[0189] In this embodiment, if the second terminal has not determined the second target resource, it only considers the impact of the received COT on the strengthening of resource selection. Specifically, the strengthening method is almost the same as steps 110-130 on the first terminal side, but the difference is that the first terminal side strengthens the resource selection based on the COT determined by itself based on the access priority, but here strengthens the resource selection based on the received COT. Similarly, it includes selecting consecutive resources and being located within the COT time.

[0190] Needless to say, the method of determining whether the available resources are contiguous or non-contiguous is similarly applied to the second terminal side.

[0191] It should be noted that, as shown in Figure 14, regarding sending the placeholder information, the first terminal and the second terminal can send the placeholder information before or after the transmission, and may be the CPE. The length of sending the placeholder information needs to be equal to or less than a second preset threshold, and the second preset threshold is related to the channel access priority or the service priority.

[0192] As shown in FIG. 10, an embodiment of the present disclosure further provides a channel access processing device for sidelink, the device comprising: a first processing module 10 used by the first terminal to perform resource selection and determine a first target resource; and a second processing module 20, which is used to perform a first type channel access procedure for at least a portion of the first target resource and to determine whether the channel is idle and a channel occupancy time COT.

[0193] Optionally, the device may further include a first transmission module used by the first terminal to transmit first control information to a second terminal, where the first control information includes information related to a COT determined by the first terminal.

[0194] Optionally, the first processing module 10 comprises: a first determination submodule used for determining a time to trigger resource selection; a second determination submodule used for determining a resource selection window based on a time for triggering resource selection; and a third determination sub-module, adapted to determine a first target resource based on the resource selection window; Here, the first time interval T1 between the start time of the resource selection window and the time of triggering resource selection is determined by the transmission processing delay, the resource selection processing delay of the first terminal, and the minimum time length for performing the first type channel access procedure.

[0195] The first time interval T1 is the first time interval T1 is greater than or equal to zero; the first time interval T1 is less than or equal to the transmission processing delay; The first time interval T1 is greater than the minimum time length; and the first time interval T1 being greater than the sum of the minimum time length and the resource selection processing delay.

[0196] In addition, the first target resources satisfy the condition that the number of the first target resources is N+M resources.

[0197] Here, N is the number of transmission resources required for transmitting the transmission block TB, and M is the number of added candidate transmission resources, where N and M are integers of 1 or more.

[0198] The value of M is A value set by a higher layer, or A value that is predefined, preset, or set by the protocol; or A value determined based on the first parameter information.

[0199] The first parameter information is Channel access priority; The priority of data, Channel busy rate, The value of N; A time length during which the first terminal has performed the first type channel access procedure in the past; and Channel occupancy and and maximum channel occupancy.

[0200] The first target resource determined is: In the available resources, resources that are continuous in the time domain, Among available resources, resources that are contiguous in time domain with resources reserved by other terminals; Among the available resources, resources that are within one maximum channel occupancy time, and The available resources include at least one of the resources that are within the same maximum channel occupancy time as the resources reserved by other terminals.

[0201] The determined first target resource further includes resources that satisfy the second condition and are discontinuous in the time domain among the available resources.

[0202] The second condition is that a second time interval between two adjacent transmissions is greater than a first predetermined threshold, the first predetermined threshold being a value set by a higher layer or a value predefined, pre-set or set by a protocol.

[0203] The second processing module 20 includes: a fourth determining sub-module used to determine a first candidate time for the first type channel access procedure to start and / or a second candidate time for the first type channel access procedure to start; a fifth determination submodule, which is used for determining an LBT start time for performing the first type channel access procedure based on the first candidate time and / or the second candidate time; and a sixth determination sub-module used to perform a first type channel access procedure for at least a portion of the first target resources based on the LBT start time.

[0204] Optionally, the fifth determining submodule includes a first determining unit, and the first determining unit includes: If the second candidate time is equal to or later than the first candidate time, determining that the LBT start time is equal to or later than the first candidate time and equal to or earlier than the second candidate time; or If the second candidate time is earlier than the first candidate time, it is used to determine that the LBT start time is equal to or later than the first candidate time.

[0205] Optionally, the fourth determination submodule includes a second determination unit, and the second determination unit is: determining a first start time at which the first terminal is triggered to perform resource selection and a processing delay for the first terminal to perform resource selection; Equation 1, A1=B1+C1, is used to determine the first candidate time.

[0206] Here, A1 denotes the first candidate time, B1 denotes the first start time, and C1 denotes a processing delay for the first terminal to perform resource selection.

[0207] Optionally, the fourth determining submodule further includes a third determining unit, and the third determining unit is: Determine a time when a resource corresponding to a first type channel access procedure is present among the first target resources according to the first target resources, and a first time length for performing the first type channel access procedure, and determine the second candidate time according to Equation 2: A2=B2-C2; or The time length required for the transmission block TB of the first target resource, the latest time of the resource selection window of the first target resource, and the first time length are determined, and are used to determine the second candidate time according to Equation 3: A2=B3-C2-D1.

[0208] Here, A2 denotes the second candidate time, B2 denotes the time where the resource is located, C2 denotes the first time length, B3 denotes the latest time in the resource selection window, and D1 denotes the time length required for the transmission block TB.

[0209] Optionally, the apparatus further comprises: A first determination module used for determining a retransmission time of the first terminal; a first execution module, which is used for executing a second type channel access procedure for at least a portion of the first target resource retransmission when the retransmission time is within the COT; The method may further include a second execution module adapted to execute a first type channel access procedure for retransmission of at least a portion of the first target resource when the retransmission time is outside the COT.

[0210] Optionally, the apparatus further comprises: a second determination module used for determining an end time at which the execution of the first type channel access procedure ends and a first time of a resource waiting to be transmitted that is closest to the end time; The method may further include a second transmitting module adapted to transmit the pending resources based on the end time and the first time.

[0211] The second sending module includes a first sending unit, or includes a fourth determining unit and a second sending unit. A first transmission unit is used to directly transmit the pending resource when the end time is equal to the first time or the distance between the end time and the first time is less than or equal to a second predetermined threshold. A fourth determining unit is used for determining a first target interval between the end time and the first time if the end time is before the first time. A second transmitting unit is used for determining to transmit the pending resources based on the first target interval.

[0212] Optionally, the second transmitting module further includes a third transmitting unit, or a fourth transmitting unit, or a fifth transmitting unit. A third sending unit is used for determining to send first placeholder information before the first time when the first target interval is equal to or greater than a first time threshold. A fourth sending unit is used for determining to send the first placeholder information before the first time if the first target interval is less than or equal to a second time threshold. A fifth sending unit is used for determining to send the first placeholder information before the first time if the first target interval is between the second time threshold and the first time threshold.

[0213] wherein a time length for transmitting the first placeholder information is equal to or less than a third predetermined threshold, and the first time threshold, the second time threshold and the third predetermined threshold are all values ​​set by a higher layer or values ​​predefined, pre-set or set by a protocol.

[0214] Optionally, the third processing module may include a first processing sub-module for causing the first terminal to transmit the first control information to a second terminal when a first condition is satisfied.

[0215] The first condition is: The remaining time of the COT is equal to or greater than a first preset threshold value; a time length for performing the first type channel access procedure is equal to or less than a second preset threshold; The number of remaining transmissions of the first terminal is equal to or less than a preset third threshold; The first terminal receives request information transmitted by the second terminal to the first terminal (the request information is used to indicate that the first terminal expects to receive the first control information transmitted by the first terminal); The first terminal has a service to transmit to the second terminal; Configuration or pre-configuration by higher layers supports COT sharing; The first terminal supports execution of COT sharing; The value of the service priority of the first terminal is smaller than a predetermined service priority threshold; The value of the channel access priority of the first terminal is less than a channel access priority threshold; and the time-frequency resource occupancy rate of the first terminal is less than a value of a time-frequency resource ratio in COT set by a higher layer or preset.

[0216] Optionally, the device further includes a third execution module, which is used for determining to terminate the first type channel access procedure when a second condition is met, and for performing a second type channel access procedure for at least a portion of the first target resources based on the second control information.

[0217] Here, the second control information includes information regarding a COT determined by the second terminal.

[0218] The second condition is as follows: The service priority of the first terminal is equal to or lower than the service priority of the second terminal; The channel access priority of the first terminal is lower than the channel access priority of the second terminal; the remaining time of the COT of the second terminal is greater than a third time threshold.

[0219] Here, the third time threshold is a value set by a higher layer, or a value predefined, pre-set or set by a protocol.

[0220] Optionally, the apparatus may further include a third determination module used to determine a maximum decoding processing delay.

[0221] In addition, the first terminal, within the maximum decoding process delay, The first terminal transmits a service to the second terminal; the first terminal transmitting second placeholder information to the second terminal, where a delay of the second placeholder information is less than or equal to a fourth predetermined threshold.

[0222] 11, an optional embodiment of the present disclosure further provides a channel access processing device for sidelink, the device including: a third processing module 30 and a fourth processing module 40. The third processing module 30 is used by the second terminal to receive first control information sent by the first terminal, the first control information including information about the COT determined by the first terminal. The fourth processing module 40 is used for performing information transmission according to the first control information.

[0223] Optionally, the fourth processing module 40 includes a fifth determining unit and a first processing unit. A fifth determining unit is used for determining the remaining time of the COT according to the first control information. The first processing unit causes the second terminal to perform a second type channel access procedure to transmit information when the transmission time of the second target resource determined by the second terminal at the first terminal is within the remaining time of the COT.

[0224] Furthermore, the start time of the second terminal performing the second type channel access procedure is a time unit before the time unit in which the second target resource is located, or The start time at which the second terminal performs the second type channel access procedure is the time unit in which the second target resource is located.

[0225] Optionally, the fourth processing module 40 comprises: A sixth determination unit is used for determining a remaining time of a COT according to the first control information; a seventh determination unit, used by the second terminal to perform resource selection and determine a second target resource according to the remaining time of the COT; The wireless communication device may further include a second processing unit used for performing information transmission based on the second target resource and the first control information.

[0226] As shown in FIG. 12 , a mobile terminal according to another embodiment of the present disclosure includes a transceiver 1210, a processor 1200, a memory 1220, and a program or instruction stored in the memory 1220 and executable by the processor 1200, and when the processor 1200 executes the program or instruction, the mobile terminal realizes the above-mentioned channel access processing method for sidelink.

[0227] The receiver-transmitter 1210 is used to receive and transmit data under the control of the processor 1200 .

[0228] In FIG. 12, the bus architecture may include any number of interconnected buses and bridges, specifically connecting various circuits between one or more processors, represented by processor 1200, and memory, represented by memory 1220. The bus architecture may further connect various other circuits, such as peripherals, regulators, and power management circuits, all of which are well known in the art and will not be described further here. The bus interface provides an interface. The transceiver 1210 may be multiple elements including a transmitter and a receiver, providing a unit for communicating with various other devices over a transmission medium. For different user equipment, the user interface may be an interface connecting the necessary equipment externally or internally, and the connected equipment includes, but is not limited to, a keypad, a display, a speaker, a microphone, a joystick, and the like.

[0229] The processor 1200 manages the bus architecture and general processing, and the memory 1220 may store data used by the processor 1200 in performing operations.

[0230] As shown in FIG. 13 , a network side device according to another embodiment of the present disclosure includes a transceiver 1310, a processor 1300, a memory 1320, and a program or instruction stored in the memory 1320 and executable by the processor 1300, and when the processor 1300 executes the program or instruction, the above-mentioned sidelink channel access processing method is realized.

[0231] The receiver-transmitter 1310 is used for receiving and transmitting data under the control of the processor 1300 .

[0232] In FIG. 13, the bus architecture may include any number of interconnected buses and bridges, specifically connecting various circuits between one or more processors, represented by processor 1300, and memory, represented by memory 1320. The bus architecture may further connect various other circuits, such as peripherals, regulators, and power management circuits, all of which are well known in the art and will not be described further here. The bus interface provides an interface. The transceiver 1310 may be multiple elements including a transmitter and a receiver, providing a unit for communicating with various other devices over a transmission medium. The processor 1300 manages the bus architecture and normal processing, and the memory 1320 may store data used by the processor 1300 in performing operations.

[0233] An embodiment of the present disclosure further provides a network side device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and when the computer program is executed by the processor, the network side device realizes each process in the above-mentioned embodiment of the sidelink channel access processing method, and can achieve the same technical effects, and will not be described in detail here to avoid duplication.

[0234] A readable storage medium according to an embodiment of the present disclosure stores a program or instruction, which, when executed by a processor, realizes steps in the channel access processing method for sidelink as described above and can achieve the same technical effect, and thus will not be described here to avoid duplication.

[0235] Here, the processor is the processor in the sidelink channel access processing method described in the above embodiment. The readable storage medium includes a computer readable storage medium such as a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0236] The terminals described in this specification include, but are not limited to, smartphones, tablet computers, etc. In addition, many of the described functional components are called modules to more particularly emphasize the independence of their implementation methods.

[0237] In embodiments of the present disclosure, modules may be implemented in software to be executed by various types of processors. For example, an identified executable code module may include one or more physical or logical blocks of computer instructions, and may be structured as, for example, an object, a process, or a function. Nevertheless, the executable code of an identified module need not be physically located in the same place, but may include different instructions stored in different locations that, when logically combined, constitute a module and achieve the intended purpose of the module.

[0238] In practice, an executable code module may be a single instruction or many instructions, and may be distributed among different code segments, among different programs, and across multiple memory devices. Similarly, operational data may be realized in modules and may be embodied in any suitable form and incorporated into any suitable type of data structure. The operational data may be collected as a single data set or may be distributed in different locations, including different storage devices, and may exist at least partially as electronic signals in a system or network.

[0239] If a module can be realized by software, after considering the level of hardware processes in the related art, for a module that can be realized by software, without considering the cost, a person skilled in the art can construct a corresponding hardware circuit to realize the corresponding function. The hardware circuit is a conventional very large scale integrated (VLSI) circuit or gate array, and a semiconductor or other independent element in the related art, such as a logic chip, a transistor, etc. The module may be implemented by a programmable hardware device, such as a field programmable gate array, a programmable array logic, a programmable logic device, etc.

[0240] The above are preferred embodiments of the present disclosure. However, those skilled in the art may make some improvements and modifications without departing from the principles described in the present disclosure, and these improvements and modifications should also be considered as part of the scope of protection of the present disclosure.

Claims

1. A sidelink channel access processing method applied to a first terminal, comprising: the first terminal performing resource selection to determine a first target resource; performing a first type channel access procedure for at least a portion of the first target resources to determine whether the channel is idle and a channel occupation time (COT); A channel access processing method for sidelink.

2. The method further includes a step of the first terminal transmitting first control information to a second terminal; The first control information includes information related to the COT determined by the first terminal. The channel access processing method for sidelink according to claim 1 .

3. The step of the first terminal performing resource selection to determine a first target resource includes: determining a time to trigger resource selection; determining a resource selection window based on a time for triggering the resource selection; determining the first target resource based on the resource selection window; Wherein, a first time interval (T1) between the start time of the resource selection window and the time of triggering the resource selection is determined by a transmission processing delay, a resource selection processing delay of the first terminal, and a minimum time length for performing the first type channel access procedure. The channel access processing method for sidelink according to claim 1 .

4. The first time interval (T1) is the first time interval (T1) being greater than or equal to zero; the first time interval (T1) being less than or equal to the transmission processing delay; the first time interval (T1) is greater than the minimum time length; the first time interval (T1) is greater than the sum of the minimum time length and the resource selection processing delay; The channel access processing method for sidelink according to claim 3.

5. The first target resource satisfies that the number of the first target resources is N+M resources; where N is the number of transmission resources required for transmitting the transmission block TB, M is the number of added candidate transmission resources, and N and M are integers equal to or greater than 1. The channel access processing method for sidelink according to claim 1 .

6. The value of M is A value set by a higher layer, or A value that is predefined, preset, or set by the protocol; or a value determined based on the first parameter information; The channel access processing method for sidelink according to claim 5.

7. The first parameter information is Channel access priority, Data priority, Channel busy rate, The value of N, A time length during which the first terminal has performed the first type channel access procedure in the past; and Channel occupancy, and maximum channel occupancy; The channel access processing method for sidelink according to claim 6.

8. The determined first target resource is In the available resources, resources that are continuous in the time domain, Among available resources, resources that are contiguous in time domain with resources reserved by other terminals; Among the available resources, resources that are within one maximum channel occupancy time, and In the available resources, the available resources include at least one of the following: a resource that is within the same maximum channel occupancy time as a resource reserved by another terminal; The channel access processing method for sidelink according to claim 1 .

9. the determined first target resource includes resources among the available resources that satisfy the second condition and are non-contiguous in the time domain; the second condition is that a second time interval between two adjacent transmissions is greater than a first predetermined threshold; The channel access processing method for sidelink according to claim 1 .

10. The step of performing a first type channel access procedure on at least a portion of the first target resources includes: determining a first candidate time for the first type of channel access procedure to be initiated and / or a second candidate time for the first type of channel access procedure to be initiated; determining an LBT start time for performing the first type channel access procedure based on the first candidate time and / or the second candidate time; and performing a first type channel access procedure for at least a portion of the first target resources based on the LBT start time. The channel access processing method for sidelink according to claim 1 .

11. The step of determining an LBT start time for executing the first type channel access procedure includes: If the second candidate time is later than or equal to the first candidate time, determining that an LBT start time is later than or equal to the first candidate time and earlier than the second candidate time or equal to the first candidate time; or if the second candidate time is earlier than the first candidate time, determining that the LBT start time is later than or equal to the first candidate time; The channel access processing method for sidelink according to claim 10.

12. The step of determining a first candidate time includes: determining a first start time at which the first terminal is triggered to perform resource selection and a processing delay for the first terminal to perform resource selection; determining the first candidate time by Equation 1, A1=B1+C1; where A1 indicates the first candidate time, B1 indicates the first start time, and C1 indicates a processing delay for the first terminal to perform resource selection. The channel access processing method for sidelink according to claim 11.

13. The step of determining the second candidate time includes: determining, based on the first target resource, a time when a resource corresponding to a first type channel access procedure is present among the first target resources, and a first time length for performing the first type channel access procedure; determining the second candidate time according to Equation 2: A2=B2-C2; or or determining a time length required for a transmission block TB of said first target resource, a latest time of a resource selection window of said first target resource, and said first time length; determining the second candidate time according to Equation 3: A2=B3-C2-D1; where A2 denotes the second candidate time, B2 denotes the time where the resource is located, C2 denotes the first time length, B3 denotes the latest time of the resource selection window, and D1 denotes the time length required for the transmission block TB. The channel access processing method for sidelink according to claim 12.

14. After determining the COT, determining a retransmission time for the first terminal; performing a second type channel access procedure for retransmission of at least a portion of the first target resources if the retransmission time is within the COT; performing a first type channel access procedure for at least a portion of the retransmission of the first target resource if the retransmission time is outside the COT. The channel access processing method for sidelink according to claim 1 .

15. After performing the first type channel access procedure, determining an end time at which execution of the first type channel access procedure ends and a first time of a resource waiting to be transmitted that is closest to the end time; transmitting the pending resources based on the end time and the first time. The channel access processing method for sidelink according to claim 1 .

16. transmitting the pending resources based on the end time and the first time, directly transmitting the pending resources if the end time is equal to the first time or is spaced from the first time by less than or equal to a second predetermined threshold; or if the end time is before the first time, determining a first target interval between the end time and the first time; and determining transmission of the pending resources based on the first target interval. The method for processing channel access for a side link according to claim 15.

17. before deciding to transmit the pending resources, determining to transmit first placeholder information before the first time if the first target interval is greater than or equal to a first time threshold; or determining to transmit the first placeholder information before the first time if the first target interval is less than or equal to a second time threshold; or determining to transmit the first placeholder information before the first time if the first target interval is between the second time threshold and the first time threshold; a time length for transmitting the first placeholder information is equal to or less than a third predetermined threshold; the first time threshold, the second time threshold, and the third predetermined threshold are all values ​​set by a higher layer, or are predefined, pre-set, or set by a protocol; The method for processing channel access for a side link according to claim 16.

18. The step of the first terminal transmitting the first control information to the second terminal includes: If a first condition is satisfied, the first terminal transmits the first control information to a second terminal; The first condition is: The remaining time of the COT is equal to or greater than a first preset threshold value; a time length for performing the first type channel access procedure is equal to or less than a second preset threshold; The number of remaining transmissions of the first terminal is equal to or less than a preset third threshold; the first terminal receiving solicitation information transmitted by the second terminal to the first terminal, the solicitation information being used to indicate an expectation of receiving the first control information transmitted by the first terminal; the first terminal having a service to transmit to the second terminal; Configuration or pre-configuration by higher layers supports COT sharing; the first terminal supports execution of COT sharing; The value of the service priority of the first terminal is smaller than a predetermined service priority threshold; The value of the channel access priority of the first terminal is less than a channel access priority threshold; the time-frequency resource occupancy rate of the first terminal is less than a value of a time-frequency resource ratio in COT set by a higher layer or preset; The channel access processing method for sidelink according to claim 2.

19. When performing a first type channel access procedure for at least a part of the first target resources, when receiving second control information transmitted by a second terminal to the first terminal, the sidelink channel access processing method includes: If a second condition is satisfied, determining to terminate the first type channel access procedure, and performing a second type channel access procedure on at least a portion of the first target resources according to the second control information; Wherein, the second control information includes information regarding a COT determined by the second terminal; The channel access processing method for sidelink according to claim 1 .

20. The second condition is: The service priority of the first terminal is equal to or lower than the service priority of the second terminal; The channel access priority of the first terminal is lower than the channel access priority of the second terminal; the remaining time of the COT of the second terminal is greater than a third time threshold; 20. The method of claim 19, wherein the channel access processing method for sidelink is

21. Before the first terminal transmits the first control information to the second terminal, determining a maximum decoding processing delay; The channel access processing method for sidelink according to claim 2.

22. The first terminal, within the maximum decoding processing delay, transmitting a service to the second terminal; transmitting second placeholder information to the second terminal, wherein a time length of the second placeholder information is equal to or less than a fourth predetermined threshold. The method of claim 21, wherein the channel access processing method for a side link is

23. A sidelink channel access processing method applied to a second terminal, comprising: a step of receiving, by the second terminal, first control information transmitted by the first terminal, the first control information including information regarding a COT determined by the first terminal; and transmitting information based on the first control information. A channel access processing method for sidelink.

24. When the second terminal receives the first control information transmitted by the first terminal and the second terminal has already determined a second target resource, The step of transmitting information based on the first control information includes: determining a remaining time of the COT based on the first control information; When the transmission time of the second target resource determined by the second terminal at the first terminal is within the remaining time of the COT, the second terminal performs a second type channel access procedure to transmit information. The method of claim 23, wherein the channel access processing method for a side link is

25. The start time of the second terminal performing the second type channel access procedure is one time unit before the time unit in which the second target resource is located; or The start time of the second terminal to perform the second type channel access procedure is a time unit in which the second target resource is located. The method of claim 24, wherein the channel access processing method for a side link is

26. When the second terminal receives first control information sent by the first terminal and the second terminal has not yet determined a second target resource, The step of transmitting information based on the first control information includes: determining a remaining COT based on the first control information; The second terminal performs resource selection to determine a second target resource based on the remaining time of the COT; and transmitting information based on the second target resource and the first control information. The method of claim 23, wherein the channel access processing method for a side link is

27. A channel access processing device for a side link, comprising: a first processing module used by the first terminal to perform resource selection and determine a first target resource; a second processing module adapted to perform a first type channel access procedure on at least a portion of the first target resources and determine whether the channel is idle and a channel occupation time (COT). A channel access processing device for the side link.

28. A channel access processing device for a side link, comprising: a third processing module used by the second terminal to receive the first control information transmitted by the first terminal; a fourth processing module used for performing information transmission based on the first control information; The first control information includes information regarding a channel occupation time (COT) determined by the first terminal. A channel access processing device for the side link.

29. A network side device, A receiver-transmitter, a processor, a memory, and a program or instructions stored in the memory and executable by the processor, When the processor executes the program or the instruction, the processor realizes the channel access method for a side link according to any one of claims 1 to 22 or the channel access method for a side link according to any one of claims 23 to 26. Network side equipment.

30. A program or instructions is stored, and when the program or instructions are executed by a processor, the program or instructions realize the channel access method for a side link according to any one of claims 1 to 22 or the channel access method for a side link according to any one of claims 23 to 26. A readable storage medium.

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