Channel access method and apparatus, terminal, chip and storage medium

Abstract

Embodiments of the present application provide a channel access method. The method comprises: sending a first physical sidelink feedback channel (PSFCH) to a second terminal, wherein the first PSFCH is used for instructing the second terminal to access a channel in a channel access mode of a specified type so as to use a reserved resource of the second terminal. In this way, the possibility of the second terminal accessing the channel in the channel access mode of the specified type can be improved; when the second terminal accesses the channel in the channel access mode of the specified type, the second terminal does not need to execute channel access of type 1; because the energy loss of the channel access process of the type 1 is high, the method is beneficial to reducing the energy loss of the second terminal executing channel access.

Description

Channel access method, device, terminal, chip and storage medium Technical Field

[0001] The embodiments of the present application relate to the field of communication technology, and specifically to a channel access method, device, terminal, chip, and storage medium. Background Art

[0002] For sideline communications operating in unlicensed spectrum, when a terminal does not have available channel occupancy time (COT), it needs to access the channel through a Type 1 channel access mechanism. This process may consume excessive energy of the terminal to perform channel access.

[0003] Summary of the Invention

[0004] Embodiments of the present application provide a channel access method, device, terminal, chip, and storage medium.

[0005] In a first aspect, an embodiment of the present application provides a channel access method, applied to a first terminal, the method comprising: sending a first physical sidelink feedback channel PSFCH to a second terminal, the first PSFCH being used to instruct the second terminal to access the channel through a specified type of channel access method to use the reserved resources of the second terminal.

[0006] In the second aspect, an embodiment of the present application provides a channel access method applied to a second terminal, the method including: receiving a first physical sidelink feedback channel PSFCH from the first terminal, the first PSFCH being used to instruct the second terminal to access the channel through a specified type of channel access method to use the reserved resources of the second terminal.

[0007] In the third aspect, an embodiment of the present application provides a channel access method, which is applied to a first terminal, and the method includes: sending inter-terminal coordination IUC information to a second terminal, where the ICU information is used to indicate multiple transmission resources of the second terminal, and the second terminal can access the channel through a specified type of channel access method to use part or all of the multiple transmission resources.

[0008] In a fourth aspect, an embodiment of the present application provides a channel access method, which is applied to a second terminal, and the method includes: receiving inter-terminal coordination IUC information from a first terminal, where the ICU information is used to indicate multiple transmission resources of the second terminal, and the second terminal can access the channel through a specified type of channel access method to use part or all of the multiple transmission resources.

[0009] In the fifth aspect, an embodiment of the present application provides a channel access device, which includes: a first sending unit, configured to send a first physical sidelink feedback channel PSFCH to a second terminal, the first PSFCH being used to instruct the second terminal to access the channel through a specified type of channel access method to use the reserved resources of the second terminal.

[0010] In the sixth aspect, an embodiment of the present application provides a channel access device, which includes: a first receiving unit, configured to receive a first physical sidelink feedback channel PSFCH from a first terminal, the first PSFCH being used to instruct a second terminal to access the channel through a specified type of channel access method to use the reserved resources of the second terminal.

[0011] In the seventh aspect, an embodiment of the present application provides a channel access device, which includes: a second sending unit, configured to send inter-terminal coordination IUC information to the second terminal, the ICU information is used to indicate multiple transmission resources of the second terminal, and the second terminal can access the channel through a specified type of channel access method to use part or all of the multiple transmission resources.

[0012] In the eighth aspect, an embodiment of the present application provides a channel access device, which includes: a second receiving unit, configured to receive inter-terminal coordination IUC information from a first terminal, the ICU information is used to indicate multiple transmission resources of the second terminal, and the second terminal can access the channel through a specified type of channel access method to use part or all of the multiple transmission resources.

[0013] In a ninth aspect, an embodiment of the present application provides a terminal comprising a processor and a memory. The memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory to perform the method described in any one of the first to fourth aspects.

[0014] In a tenth aspect, an embodiment of the present application provides a chip. The chip includes: a processor configured to call and execute a computer program from a memory, so that a device equipped with the chip executes the method described in any one of the first to fourth aspects.

[0015] In an eleventh aspect, an embodiment of the present application provides a computer-readable storage medium for storing a computer program, which enables a computer to execute the method described in any one of the first to fourth aspects.

[0016] In a twelfth aspect, an embodiment of the present application provides a computer program product, comprising computer program instructions, which enable a computer to execute the method described in any one of the first to fourth aspects.

[0017] In a thirteenth aspect, an embodiment of the present application provides a computer program, which, when executed on a computer, enables the computer to execute the method described in any one of the first to fourth aspects.

[0018] In this method, a first terminal may transmit a first PSFCH to a second terminal. The first PSFCH is used to instruct the second terminal to access the channel using a specified type of channel access method to use the second terminal's reserved resources. This increases the likelihood that the second terminal will access the channel using the specified type of channel access method. If the second terminal accesses the channel using the specified type of channel access method, the second terminal may not need to perform Type 1 channel access. Since Type 1 channel access consumes a relatively high amount of energy, this method is beneficial in reducing the energy consumption of the second terminal performing channel access. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0020] FIG1 is a schematic diagram of an example in which part of symbols in a time slot are used for SL transmission according to an embodiment of the present application;

[0021] FIG2 is a schematic diagram of an example of a time slot structure of PSCCH and PSSCH provided in an embodiment of the present application;

[0022] FIG3 is a schematic diagram of the time domain positions of four DMRS symbols when the PSSCH has 13 symbols, provided by an embodiment of the present application;

[0023] FIG4 is a schematic diagram of an example of a PSSCH DMRS frequency domain position provided in an embodiment of the present application;

[0024] FIG5 is a schematic diagram of an example of a PSCCH and PSSCH resource pool in NR-V2X provided in an embodiment of the present application;

[0025] FIG6 is a schematic diagram of an example of an interleaved resource block provided in an embodiment of the present application;

[0026] FIG7 is a schematic diagram of an example of a frame structure based on interleaved resource blocks provided in an embodiment of the present application;

[0027] FIG8 is a schematic diagram of an example of an RB set provided in an embodiment of the present application;

[0028] FIG9 is a flow chart of a channel access method according to an embodiment of the present application;

[0029] FIG10 is a schematic diagram of a first PSFCH transmission opportunity provided in an embodiment of the present application;

[0030] FIG11 is a second flow chart of a channel access method according to an embodiment of the present application;

[0031] FIG12 is a schematic diagram of the structure of a channel access device according to an embodiment of the present application;

[0032] FIG13 is a second schematic diagram of the structure of the channel access device provided in an embodiment of the present application;

[0033] FIG14 is a third schematic diagram of the structure of the channel access device provided in an embodiment of the present application;

[0034] FIG15 is a fourth schematic diagram of the structure of the channel access device provided in an embodiment of the present application;

[0035] FIG16 is a schematic structural diagram of a communication device provided in an embodiment of the present application;

[0036] FIG17 is a schematic structural diagram of a chip according to an embodiment of the present application. DETAILED DESCRIPTION

[0037] The following will describe the technical solutions in the embodiments of this application in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0038] The technical solutions of the embodiments of the present application can be applied to various side communication systems. To facilitate understanding of the technical solutions of the embodiments of the present application, the relevant technologies of the embodiments of the present application are explained below. The following related technologies can be arbitrarily combined with the technical solutions of the embodiments of the present application as optional solutions, and they all fall within the protection scope of the embodiments of the present application.

[0039] 1. Timeslot Structure in New Radio-Vehicle to Everything (NR-V2X)

[0040] In NR-V2X, the Physical Sidelink Shared Channel (PSSCH) and its associated Physical Sidelink Control Channel (PSCCH) are transmitted in the same time slot, and the PSCCH occupies 2 or 3 time domain symbols. Among them, the time domain resource allocation of NR-V2X is based on the time slot as the allocation granularity, and the parameters sl-startSLsymbols and sl-lengthSLsymbols are used to configure the starting point and length of the time domain symbols used for sidelink transmission in a time slot. The last symbol in this part of symbols is used as the guard period (GP), and PSSCH and PSCCH can only use the remaining time domain symbols. However, if the Physical Sidelink Feedback Channel (PSFCH) transmission resources are configured in a time slot, then PSSCH and PSCCH cannot occupy the time domain symbols used for PSFCH transmission, as well as the automatic gain control (AGC) and GP symbols before the symbol.

[0041] Figure 1 shows how some symbols in a time slot are used for sidelink (SL) transmission. As shown in Figure 1, if the network configuration sl-StartSymbol = 3 and sl-LengthSymbols = 11, then the 11 time-domain symbols starting from symbol index 3 in a time slot can be used for sidelink transmission. This time slot contains PSFCH transmission resources, which occupy symbols 11 and 12. Symbol 11 serves as the PSFCH AGC symbol, and symbols 10 and 13 serve as GPs. The time-domain symbols available for PSSCH transmission are symbols 3 through 9. The PSCCH occupies three time-domain symbols: symbols 3, 4, and 5, with symbol 3 typically used as the AGC symbol.

[0042] In NR-V2X, in addition to PSCCH and PSSCH, PSFCH may also exist in a sidelink time slot, as shown in Figure 2. In a time slot, the first Orthogonal Frequency Division Multiplexing (OFDM) symbol is fixed for automatic gain control AGC. On the AGC symbol, the UE copies the information sent on the second symbol. One symbol is reserved at the end of the time slot for transceiver conversion, which is used for the UE to switch from the transmit (or receive) state to the receive (or transmit) state. In the remaining OFDM symbols, the PSCCH can occupy two or three OFDM symbols starting from the second sidelink symbol. In the frequency domain, the number of physical resource blocks (PRBs) occupied by the PSCCH is within the subband range of a PSSCH. If the number of PRBs occupied by the PSCCH is less than the size of a subchannel of the PSSCH, or the frequency domain resources of the PSSCH include multiple subchannels, the PSCCH can be frequency-division multiplexed with the PSSCH on the OFDM symbol where the PSCCH is located.

[0043] The DMRS for the PSSCH in NR-V2X draws on the design of the New Radio (NR) Uu interface and uses multiple time-domain PSSCH DMRS patterns. Within a resource pool, the number of available DMRS patterns is related to the number of PSSCH symbols in the resource pool. For a specific number of PSSCH symbols (including the first AGC symbol) and PSCCH symbols, the available DMRS patterns and the position of each DMRS symbol within the pattern are shown in Table 1. Figure 3 shows a schematic diagram of the time-domain positions of four DMRS symbols when the PSSCH has 13 symbols.

[0044] Table 1 Number and position of DMRS symbols under different PSSCH and PSCCH symbol numbers

[0045] If multiple time-domain DMRS patterns are configured in the resource pool, the specific time-domain DMRS pattern to be used is selected by the transmitting UE and indicated in the first-order Sidelink Control Information (SCI). This design allows high-speed UEs to select a high-density DMRS pattern to ensure channel estimation accuracy, while low-speed UEs can use a low-density DMRS pattern to improve spectrum efficiency.

[0046] The generation method of the PSSCH DMRS sequence is almost identical to that of the PSCCH DMRS sequence. The only difference is the initialization formula c(m) of the pseudo-random sequence. init middle, p i The i-th CRC bit of the PSCCH that schedules the PSSCH, where L=24 is the number of bits of the PSCCH CRC.

[0047] The NR physical downlink shared channel (PDSCH) and physical uplink shared channel (PUSCH) support two frequency domain DMRS patterns, namely DMRS frequency domain type 1 and DMRS frequency domain type 2. For each frequency domain type, there are two different types: single DMRS symbol and double DMRS symbol. Single-symbol DMRS frequency domain type 1 supports 4 DMRS ports, and single-symbol DMRS frequency domain type 2 can support 6 DMRS ports. In the case of double DMRS symbols, the number of supported ports is doubled. However, in NR-V2X, since PSSCH only needs to support two DMRS ports at most, only single-symbol DMRS frequency domain type 1 is supported, as shown in Figure 4.

[0048] 2. Determination of NR-V2X frequency domain resources

[0049] Similar to LTE-V2X, the frequency domain resources in the NR-V2X resource pool are contiguous, and the frequency domain resource allocation granularity is also subchannel. The number of PRBs included in a subchannel is {10, 12, 15, 20, 50, 75, 100}. The minimum subchannel size is 10 PRBs, which is much larger than the minimum subchannel size of 4 PRBs in LTE-V2X. This is mainly because the frequency domain resources of the PSCCH in NR-V2X are located in the first subchannel of its associated PSSCH. The frequency domain resources of the PSCCH are less than or equal to the size of a PSSCH subchannel, while the time domain resources of the PSCCH occupy two or three OFDM symbols. If the subchannel size is configured too small, the available PSCCH resources will be limited, the code rate will increase, and the detection performance of the PSCCH will be reduced. In NR-V2X, the PSSCH subchannel size and the PSCCH frequency domain resource size are configured independently, but the PSCCH frequency domain resources must be less than or equal to the PSSCH subchannel size.

[0050] The following configuration parameters in the NR-V2X resource pool configuration information are used to determine the frequency domain resources of the PSCCH and PSSCH resource pools:

[0051] 1) Subchannel size (sl-SubchannelSize): indicates the number of consecutive PRBs included in a subchannel in the resource pool, and the value range is {10, 12, 15, 20, 50, 75, 100} PRBs;

[0052] 2) Number of subchannels (sl-NumSubchannel): indicates the number of subchannels included in the resource pool;

[0053] 3) Subchannel starting RB index (sl-StartRB-Subchannel): indicates the starting PRB index of the first subchannel in the resource pool;

[0054] 4) PRB number (sl-RB-Number): indicates the number of consecutive PRBs included in the resource pool;

[0055] 5) PSCCH frequency domain resource indication (sl-FreqResourcePSCCH): indicates the frequency domain resource size of PSCCH, and the value range is {10, 12, 15, 20, 25} PRB.

[0056] When the UE determines the resource pool for PSSCH transmission or PSSCH reception, the frequency domain resources included in the resource pool are sl-NumSubchannel consecutive subchannels starting from the PRB indicated by sl-StartRB-Subchannel. If the number of PRBs contained in the final sl-NumSubchannel consecutive subchannels is less than the number of PRBs indicated by sl-RB-Number, the remaining PRBs cannot be used for PSSCH transmission or reception.

[0057] In NR-V2X, the frequency domain starting position of the first subchannel of PSCCH and its associated PSSCH is aligned. Therefore, the starting position of each PSSCH subchannel is the possible frequency domain starting position of PSCCH. According to the above parameters, the frequency domain range of the resource pool of PSCCH and PSSCH can be determined, as shown in Figure 5.

[0058] In NR-V2X, PSCCH is used to carry side control information related to resource sensing, including:

[0059] 1) The priority of the scheduled transmission;

[0060] 2) Frequency domain resource allocation: Indicates the number of frequency domain resources of PSSCH in the current time slot scheduled by PSCCH, as well as the number and starting position of frequency domain resources of up to two retransmission resources reserved;

[0061] 3) Time domain resource allocation: indicates the time domain locations of up to two retransmission resources;

[0062] 4) PSSCH reference signal pattern;

[0063] 5) Second-level SCI format;

[0064] 6) Second-order SCI rate offset;

[0065] 7) Number of PSSCH DMRS ports;

[0066] 8) Modulation and Coding Scheme (MCS);

[0067] 9)MCS form instructions;

[0068] 10) Number of PSFCH symbols;

[0069] 11) Resource reservation period: reserves resources for sending another transport block (TB) in the next period. If inter-TB resource reservation is not activated in the resource pool configuration, this information bit field does not exist.

[0070] 12) Reserved bits: 2 to 4 bits. The specific number of bits is configured or pre-configured by the network.

[0071] Since the PSCCH is always transmitted in the same time slot as the scheduled PSSCH, and the starting position of the PRB occupied by the PSCCH is the starting position of the first subchannel of the scheduled PSSCH, the SCI format 1-A does not explicitly indicate the time-frequency domain starting position of the scheduled PSSCH.

[0072] 3. Sidelink Over Unlicensed Spectrum (SL-U)

[0073] When performing sidelink transmissions on unlicensed spectrum, sidelink transmissions must meet specific regulatory requirements, including minimum occupied channel bandwidth (OCB) and maximum power spectral density (PSD). For OCB requirements, the UE must occupy no less than 80% of the channel bandwidth when using the channel for data transmission. For maximum power spectral density requirements, the UE's transmit power per 1MHz cannot exceed 10dBm. To meet OCB and PSD regulatory requirements, sidelink transmissions on unlicensed spectrum must adopt an interlaced resource block (IRB) structure. An IRB consists of N discrete resource blocks (RBs) in the frequency domain, with a total of M IRBs within the frequency band. The mth IRB consists of RBs in the order {m, M+m, 2M+m, 3M+m, ...}.

[0074] Figure 6 shows an example of interleaved resource blocks. As shown in Figure 6, the system bandwidth consists of 20 RBs, including 5 IRBs (i.e., M = 5). Each IRB consists of 4 RBs (i.e., N = 4). Adjacent RBs in the same IRB have the same frequency domain spacing, i.e., 5 RBs apart. The numbers in the boxes in the figure represent the IRB indexes.

[0075] In the SL-U system, if IRB-based resource allocation granularity is adopted, channels such as the PSCCH and PSSCH in the SL-U system should all be based on the IRB structure. In this case, the frame structure of the SL-U system is shown in Figure 7. The numbers in the boxes in Figure 7 represent the IRB index. Figure 7 illustrates a frame structure in which only the PSCCH and PSSCH are included in a time slot, excluding the PSFCH. The bandwidth shown in the figure includes 20 RBs, with five IRB resources configured (i.e., M = 5). Each IRB resource consists of four RBs, and the numbers in the boxes represent the IRB index. In Figure 7, the system configures the PSCCH to occupy one IRB resource and two OFDM symbols in the time domain. The PSSCH uses IRB granularity, with the first symbol in the time slot being an AGC symbol and the last symbol being a GP symbol. In the figure, PSSCH1 occupies IRB#0 and IRB#1, with its corresponding PSCCH1 occupying IRB#0. PSSCH2 occupies IRB#2, with its corresponding PSCCH2 also occupying IRB#2. It should be noted that, for the sake of simplicity, FIG7 does not show the resources occupied by the second-order SCI and the resources occupied by the PSCCH DMRS and PSSCH DMRS.

[0076] In unlicensed spectrum, UEs access channels using Listen Before Talk (LBT). LBT uses a 20MHz granularity in the frequency domain, with each 20MHz interval being called an RB Set. A carrier can contain multiple RB Sets, separated by guard intervals, as shown in Figure 8.

[0077] 4. Channel access in unlicensed spectrum

[0078] UEs on unlicensed spectrum can access channels through Type 1, Type 2A, Type 2B, or Type 2C LBT.

[0079] Type 1 channel access:

[0080] Taking the base station as an example, the channel access parameters corresponding to the channel access priority p on the base station side are shown in Table 2. In Table 2, m p Refers to the number of fallback slots corresponding to the channel access priority p, CW p Refers to the contention window (CW) size corresponding to the channel access priority p, CWmin,p Refers to the CW corresponding to the channel access priority p p Minimum value, CW max,p Refers to the CW corresponding to the channel access priority p p The maximum value, T mcot,p It refers to the maximum channel occupancy time corresponding to the channel access priority p.

[0081] The base station can select the corresponding channel access priority p according to the priority of the service to be transmitted, and obtain the channel occupancy time (COT) on the unlicensed spectrum carrier in a Type 1 channel access mode according to the channel access parameters corresponding to the channel access priority p in Table 2. Within the obtained COT, the base station can transmit continuously or discontinuously. The above-mentioned Type 1 LBT initiated COT by the base station may specifically include the following steps:

[0082] 1) Set counter N = N init , where N init is 0 to CW p Random numbers uniformly distributed between , execute step 4).

[0083] 2) If N>0, the base station decrements the counter by 1, that is, N=N-1.

[0084] 3) Make the channel length T sl (T sl The monitoring time slot detection indicates an LBT monitoring time slot with a length of 9 μs. If the monitoring time slot is idle, execute step 4); otherwise, execute step 5).

[0085] 4) If N=0, end the channel access process; otherwise, execute step 2).

[0086] 5) Make the channel time length T d (where T d =16+m p *9[μs]) monitoring time slot detection, the result of the monitoring time slot detection is divided into two cases, one case is that at least one monitoring time slot is occupied, and the other case is that all monitoring time slots are idle.

[0087] 6) If the channel monitoring result is T d If all monitoring time slots are idle within the time limit, execute step 4); otherwise, execute step 5).

[0088] Table 2 Channel access parameters corresponding to different channel access priorities p

[0089] If the channel access process is completed, the base station can use the channel for transmission. The maximum length of time the base station can use the channel for transmission cannot exceed T mcot,p .

[0090] Before the base station starts step 1) of the above Type 1 channel access method, the base station needs to maintain and adjust the contention window CW p Initially, the contention window CW p The size is set to the minimum value CW min,p ; During transmission, the contention window CW p The size of the CW can be determined based on the ACK (Acknowledgement, ACK) or NACK (Negative Acknowledgement, NACK) information fed back by the terminal received by the base station. p If the contention window CW p Increased to maximum CW max,p , and the maximum competition window CW max,p After a certain number of times, the competition window CW p The size can be reset to the minimum value CW min,p .

[0091] It should be noted that after the communication device successfully performs the above-mentioned Type 1 LBT, it can initiate the channel occupancy time COT on the unlicensed spectrum carrier. The communication device can transmit within the COT or share the COT with other communication devices. If the communication device does not immediately access the channel for data transmission, if the communication device needs to transmit later, it does not need to perform the above-mentioned Type 1 LBT again, but only needs to perform a shorter LBT. For example, the terminal can only perform a time of T sl +T d If the channels are idle during the monitoring time, the communication device can access the channel for transmission. Otherwise, the communication device needs to perform Type 1 LBT again to initiate COT.

[0092] Type 2A / 2B / 2C channel access:

[0093] When a communication device transmits within a COT, it can access the channel using Type 2A / 2B or 2C LBT. These three channel access methods are collectively referred to as Type 2 channel access methods. Specifically, under Type 2A channel access, the terminal can monitor the channel for 25μs before starting transmission and transmit after successful channel monitoring. Under Type 2B channel access, the terminal can monitor the channel for 16μs before starting transmission and transmit after successful channel monitoring. The gap between the start position of the transmission and the end position of the previous transmission is 16μs. Under Type 2C channel access, the terminal can directly transmit. The gap between the start position of the transmission and the end position of the previous transmission is no more than 16μs, and the length of the transmission does not exceed 584μs.

[0094] In the SL-U system, when there is no available COT, the terminal can access the channel and send S-SSB via Type 2-A when the following conditions are met: the sending duration does not exceed 1ms; the duty cycle of sending S-SSB does not exceed 1 / 20.

[0095] 5. First-order SCI and second-order SCI in NR SL

[0096] A second-order SCI design is supported in NR SL, where the first-order SCI used to schedule PSSCH and / or SL PRS transmission is called SCI format 1-A and contains the following information:

[0097] 1) Priority of scheduled data: 3 bits, 000 represents a priority value of 1, 001 represents a priority value of 2, and so on.

[0098] 2) Frequency resource assignment:

[0099] Contains a frequency resource indicator value (FRIV);

[0100] If an SCI can indicate the current transmission resource and a reserved resource for retransmission of the current transport block (TB), FRIV is bits, used to indicate the initial subchannel index of the reserved resource and the number of subchannels included in the current transmission resource and the one reserved resource;

[0101] If one SCI can indicate the current transmission resource and two reserved resources for the current TB retransmission, the FRIV is bits, used to indicate the initial subchannel index of the two reserved resources and the number of subchannels included in the current transmission resource and the two reserved resources.

[0102] 3) Time resource assignment:

[0103] Contains a Time Resource Indicator Value (TRIV). If a PSCCH can indicate the current transmission resource and a reserved resource for the current TB retransmission, the TRIV is 5 bits, used to indicate the time slot interval of the reserved resource relative to the current transmission resource; if a PSCCH can indicate the current transmission resource and two other reserved resources for the current TB retransmission, the TRIV is 9 bits, used to indicate the time slot interval of the two reserved resources relative to the current transmission resource, i.e., the values ​​of t1 and t2 in Figure 3-12, where the time slot interval is expressed as the number of time slots belonging to the current resource pool.

[0104] 4) PSSCH reference signal pattern: bits, where N pattern The number of DMRS patterns allowed in the current resource pool.

[0105] 5) Second-order SCI format: 2 bits.

[0106] 00 represents SCI format 2-A, 01 represents SCI format 2-B, 10 represents SCI format 2-C, and 11 is reserved for future versions.

[0107] 6) Second-order SCI rate offset: 2 bits, 00, 01, 10, and 11 represent the first, second, third, and fourth rate offset values ​​configured by the RRC layer, respectively.

[0108] 7) PSSCH DMRS port number: 1 bit, 0 indicates one port (port 1000), and 1 indicates two ports (ports 1000 and 1001).

[0109] 8) Modulation and Coding Scheme (MCS): 5 bits.

[0110] 9) MCS table indication: 0 to 2 bits, depending on the number of MCS tables allowed to be used configured in the resource pool.

[0111] 10) PSFCH symbol number: 1 bit if the PSFCH period is 2 or 4 slots, otherwise 0 bit.

[0112] 11) Resource Reservation Period: 4 bits; reserves resources for transmission by another TB in the next period. If inter-TB resource reservation is not activated in the resource pool configuration, this information bit field does not exist.

[0113] 12) Reserved bits: 2 to 4 bits. The specific number of bits is configured or pre-configured by the network.

[0114] When the resource pool is configured to indicate whether the terminal supports receiving resource conflict indication through the least significant bit (LSB) of the reserved bit, if the terminal supports this function, the first reserved bit is set to "1", otherwise it is set to "0"; the values ​​of other reserved bits are all set to "0".

[0115] Currently, NR SL defines four second-level SCI formats, namely SCI format 2-A, SCI format 2-B, SCI format 2-C, and SCI format 2-D. SCI format 2-A has a total of 35 bits and contains the following information:

[0116] 1) Hybrid Automatic Repeat reQuest (HARQ) process: 4 bits.

[0117] 2) New Data Indicator (NDI): 1 bit.

[0118] 3) Redundancy Version (RV): 2 bits.

[0119] 4) Source ID: 8 bits.

[0120] 5) Target ID: 6 bits.

[0121] 6) HARQ feedback activation / deactivation: 1 bit.

[0122] 7) Unicast / multicast / broadcast indication: 2 bits.

[0123] 00 indicates broadcast, 01 indicates a multicast communication mode that requires feedback of ACK or NACK, 10 indicates unicast, and 11 indicates a multicast communication mode that only requires feedback of NACK.

[0124] 8) CSI feedback request: 1 bit.

[0125] SCI format 2-B has a total of 48 bits and is used only to indicate multicast service transmission. Therefore, compared with SCI format 2-A, SCI format 2-B does not contain the unicast / multicast / broadcast indication field and the CSI feedback request field, but additionally contains the following two information fields:

[0126] 1) Zone ID: 12 bits.

[0127] 2) Communication distance requirement: 4 bits.

[0128] SCI format 2-C is used to carry inter-UE coordination requests or inter-UE coordination information. The information contained in the indication is divided into two parts. The first part is the other bit fields in SCI format 2-A except the "unicast / multicast / broadcast indication" field. If the SCI format 2-C carries an inter-UE coordination request, the second part contains the following additional information:

[0129] 1) Trigger signaling or reference resource set indication: 1 bit.

[0130] 2) Priority: 3 bits.

[0131] 3) Number of sub-channels: bits, of which The number of sub-channels in the current resource pool.

[0132] 4) Resource reservation period: If periodic resource reservation is allowed in the current resource pool, then bits, where N rsv_period The total number of resource reservation periods configured in the current resource pool. If periodic resource reservation is not allowed in the current resource pool, the bit is 0.

[0133] 5) Resource selection window: Bits are used to indicate the direct frame number (DFN) and time slot index corresponding to the start and end points of the resource selection window. μ=0, 1, 2, 3 are subcarrier spacing indexes.

[0134] 6) Resource type: If the current resource pool configuration is that the resource type is determined by UE-B, it is 1 bit, otherwise it is 0 bit.

[0135] 7) Padding bits.

[0136] If SCI format 2-C carries inter-UE coordination information, the second part contains the following additional information:

[0137] 1) Trigger signaling or reference resource set indication: 1 bit.

[0138] 2) 2 combinations of {TRIV, FRIV, reserved period} - 2(N TRIV +N FRIV +Y) bits.

[0139] Among them, N TRIV=9; If periodic resource reservation is allowed in the current resource pool, then bit, otherwise it is 0 bit;

[0140] 3) Time domain position of the first resource: 8 bits, used to indicate the interval of the first resource in the second TRIV relative to the reference time slot, in time slots, with a value range of 0 to 255.

[0141] 4) Reference time slot: Bit used to indicate the DFN and timeslot index of the reference timeslot, where μ = 0, 1, 2, 3 is the subcarrier spacing index.

[0142] 5) Frequency domain position of the first resource: Bit used to indicate the frequency domain starting position of the first resource in the first TRIV and the second TRIV.

[0143] 6. PSFCH in NR SL

[0144] R16NR-V2X supports a sequence type of PSFCH, called PSFCH format 0. This type of PSFCH occupies one PRB in the frequency domain and one OFDM symbol in the time domain. The sequence type used is the same as PUCCH format 0. In a resource pool, PSFCH resources are configured with a period of 1, 2, or 4 time slots. In the time slot where PSFCH resources exist, the PSFCH resources are located on the last OFDM symbol in the time slot that can be used for sideline transmission. However, in order to support transceiver conversion and AGC adjustment, there are two OFDM symbols before the PSFCH symbol for transceiver conversion and AGC adjustment respectively. In addition, PSCCH and PSSCH transmission are not allowed on the above three OFDM symbols.

[0145] In R16NR-V2X, PSFCH is only used to carry HARQ feedback information, and the capacity of one PSFCH is one bit. In R18, in addition to carrying HARQ feedback information, PSFCH is also used to carry resource conflict indication information. In order to ensure backward compatibility, the period of the PSFCH resources used for conflict indication and the time slot where the PSFCH resources are located in each PSFCH resource period are the same as the PSFCH resources used for HARQ-ACK feedback in the resource pool. This also means that resource conflict indication can only be performed in the resource pool configured with PSFCH resources for HARQ-ACK feedback. In addition, in the time slot where the PSFCH resources are located, the PRBs occupied by the PSFCH resources used for HARQ-ACK feedback and the PRBs occupied by the PSFCH resources used for resource conflict indication are different, so as to avoid mutual influence between resource conflict indication and HARQ-ACK feedback.

[0146] The time domain position of the PSFCH used for conflict indication can be determined based on the time slot n where the conflicting resource is located. cnf OK, in this case the PSFCH used for conflict indication is located at n cnf - Before T3 (including n cnf -T3) is the first time slot where a PSFCH resource for conflict indication exists, and the time slot where the PSFCH for conflict indication is located is the same as the time slot where the SCI indicating the conflicting resource is located. SCI The interval between them must be no less than X, otherwise UE-A will not send a resource conflict indication. Where X is the minimum interval between the SCI and PSFCH configured in the resource pool, which is the same as the minimum interval between the PSFCH carrying HARQ-ACK and the SCI.

[0147] The time domain position of the PSFCH used for conflict indication can also be determined based on the time slot n where the SCI indicating the conflicting resource is located. SCI OK, in this case the PSFCH used for conflict indication is located at n SCI +X(including n SCI +X) after the first time slot where there is a PSFCH resource for conflict indication, and the time slot where the PSFCH for conflict indication is located is the same as the time slot where the conflicting resource is located. cnf The interval between them must be no less than T3, otherwise UE-A will not send a resource conflict indication.

[0148] At the determined PSFCH time domain position, the PSFCH transmission resources are determined based on the time-frequency position of the corresponding PSSCH transmission resources. NR-V2X supports the following two PSFCH resource determination methods. The specific method used to determine the PSFCH resources is configured based on higher-layer signaling.

[0149] Method 1: Determine the PSFCH transmission resource based on the first sub-channel of the PSSCH frequency domain resource;

[0150] Method 2: Determine the PSFCH transmission resources based on all sub-channels occupied by the PSSCH frequency domain.

[0151] For Method 1, since PSFCH transmission resources are determined only based on the first subchannel occupied by the PSSCH, the number of PSFCH feedback resources remains fixed regardless of the number of subchannels occupied by the PSSCH. For Method 2, the number of PSFCH transmission resources is determined based on the number of subchannels occupied by the PSSCH. Therefore, the more subchannels occupied by the PSSCH, the more PSFCH transmission resources are allocated. Method 2 is more suitable for scenarios requiring more sidelink HARQ feedback resources, such as the second type of sidelink HARQ feedback in multicast.

[0152] The corresponding PSFCH transmission resource set can be determined based on the time slot and subchannel of the PSSCH transmission The index of the PSFCH transmission resource in the resource set is first determined in the order of RB from low to high, and then in the order of cyclic shift (CS) from low to high. Furthermore, in the resource set, the PSFCH transmission resource is determined by the following formula:

[0153] Among them, P ID Indicates the sender ID information, that is, the source ID of the sender UE carried in the SCI. For unicast or NACK-only multicast side HARQ feedback mode, M ID = 0; for ACK / NACK multicast side HARQ feedback mode, M ID Indicates the intra-group identifier of the receiving UE configured by the higher layer.

[0154] 7. Energy saving in sidelink

[0155] In scenarios such as smart homes and smart factories, sidewalk communications may be used for wearable device communications. In these scenarios, ensuring low cost and low power consumption of devices is extremely important. However, in existing sidewalk communication systems, terminals need to access channels in unlicensed spectrum through LBT. During the LBT process, the UE may need to monitor the channel for a long time and cannot enter deep sleep state.

[0156] The above briefly explains the relevant technologies / terms involved in the embodiments of this application, which will not be repeated in the following embodiments.

[0157] It should be understood that the terms "system" and "network" are often used interchangeably in this document. The term "and / or" in this document is merely a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this document generally indicates that the objects associated before and after are in an "or" relationship. It should also be understood that the "indication" mentioned in the embodiments of this application can be a direct indication, an indirect indication, or an indication of an association relationship. For example, A indicates B, which can mean that A directly indicates B, for example, B can be obtained through A; it can also mean that A indirectly indicates B, for example, A indicates C, and B can be obtained through C; it can also mean that there is an association relationship between A and B. It should also be understood that the "correspondence" mentioned in the embodiments of this application can mean that there is a direct or indirect correspondence between the two, or it can mean that there is an association relationship between the two, or it can mean a relationship between indication and indication, configuration and configuration, etc. It should also be understood that the “predefined” or “predefined rules” mentioned in the embodiments of the present application can be implemented by pre-saving corresponding codes, tables or other methods that can be used to indicate relevant information in devices (for example, including terminal devices and network devices), and the present application does not limit its specific implementation method. For example, predefined can refer to what is defined in the protocol. It should also be understood that in the embodiments of the present application, the “protocol” may refer to a standard protocol in the field of communications, such as LTE protocols, NR protocols, and related protocols used in future communication systems, and the present application does not limit this.

[0158] It should also be understood that the embodiments of the present application do not limit the specific form of the terminal. As an example, the terminal in the embodiments of the present application may refer to an access terminal, a user equipment (UE), a user unit, a user station, a mobile station, a mobile station, a remote station, a remote terminal, a mobile device, a user terminal, a terminal device, a wireless communication device, a user agent or a user device. The access terminal may be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, an IoT device, a satellite handheld terminal, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a handheld device with wireless communication capabilities, a computing device or other processing device connected to a wireless modem, an in-vehicle device, a wearable device, a terminal device in a 5G network or a terminal device in a future evolution network, etc.

[0159] For sideline communications operating in unlicensed spectrum, when a terminal does not have an available COT, it needs to access the channel through the Type 1 channel access mechanism. This process may consume excessive energy of the terminal to perform channel access.

[0160] In view of this, the present application provides a channel access method, apparatus, terminal, chip, and storage medium. In this method, a first terminal may send a first PSFCH to a second terminal, and the first PSFCH is used to instruct the second terminal to access the channel through a specified type of channel access method to use the reserved resources of the second terminal. In this way, the possibility of the second terminal accessing the channel through the specified type of channel access method can be increased. When the second terminal accesses the channel through the specified type of channel access method, the second terminal may not need to perform type 1 channel access. Since the energy loss of the type 1 channel access process is relatively high, this method is conducive to reducing the energy loss of the second terminal performing channel access.

[0161] To facilitate understanding of the technical solutions of the embodiments of the present application, the technical solutions of the present application are described in detail below through specific embodiments. The above related technologies can be combined arbitrarily with the technical solutions of the embodiments of the present application as optional solutions, and all of them fall within the scope of protection of the embodiments of the present application. The embodiments of the present application include at least part of the following contents.

[0162] FIG9 is a flow chart of a channel access method according to an embodiment of the present application. As shown in FIG9 , the method may include the following steps:

[0163] S901: A first terminal sends a first PSFCH to a second terminal. The first PSFCH is used to instruct the second terminal to access a channel through a specified type of channel access method to use reserved resources of the second terminal.

[0164] The reserved resources of the second terminal may be, for example, the reserved resources indicated by the second terminal via the SCI. In some embodiments, the reserved resources may be used by the second terminal for retransmission of the current TB or for initial transmission (new transmission) of a new TB.

[0165] In this embodiment, the first terminal may send a first PSFCH to the second terminal, and accordingly, the second terminal may receive the first PSFCH from the first terminal. As an example, the first terminal may send the first PSFCH to the second terminal by, for example, sending information carried in the first PSFCH to the second terminal via the first PSFCH, or performing channel transmission (such as channel transmission in a specific format) on the time-frequency resources corresponding to the first PSFCH.

[0166] The first PSFCH may be used to instruct the second terminal to access the channel using a specified type of channel access method in order to use the second terminal's reserved resources. Thus, after receiving the first PSFCH, the second terminal may access the channel using the specified type of channel access method, thereby using the second terminal's reserved resources. For example, after accessing the channel using the specified type of channel access method, the second terminal may use the reserved resources to transmit a sidelink channel (e.g., to transmit information carried on the sidelink channel).

[0167] In some embodiments, the first PSFCH is located in the time domain at: the last PSFCH transmission opportunity before the reserved resources; or, the last PSFCH transmission opportunity before the first moment; wherein the first moment is before the time slot where the reserved resources are located, and the time interval between the first moment and the start moment of the time slot where the reserved resources are located is: the sum of the maximum duration of the currently configured extended cyclic prefix (Cyclic Prefix Extension, CPE) and the first duration, the first duration is defined by the standard, configured by the network or pre-configured, and the first duration can be used for the terminal to receive and process the PSFCH.

[0168] For example, a PSFCH transmission opportunity in the embodiments of the present application refers to one or more consecutive OFDM symbols containing PSFCH resources. For example, in Figure 10, three PSFCH transmission opportunities are shown, namely PSFCH transmission opportunity #1, PSFCH transmission opportunity #2, and PSFCH transmission opportunity #3.

[0169] In one example, the first PSFCH is located in the time domain at the last PSFCH transmission opportunity before the reserved resources. Taking Figure 10 as an example, assuming that the reserved resources are located in time slot n, then the last PSFCH transmission opportunity before the reserved resources is the PSFCH transmission opportunity in time slot n-1. In other words, the first PSFCH can be located in the PSFCH transmission opportunity in time slot n-1 (i.e., PSFCH transmission opportunity #3) in the time domain. In this case, the first terminal can send the first PSFCH to the second terminal at PSFCH transmission opportunity #3, thereby instructing the second terminal to access the channel using a specified type of channel access method to use the reserved resources in time slot n.

[0170] In another example, the first PSFCH is located in the time domain at: the last PSFCH transmission opportunity before the first moment, that is, the last PSFCH transmission opportunity before the end of the OFDM symbol before the first moment. The first moment is before the time slot where the reserved resource is located, and the time interval between the first moment and the start moment of the time slot where the reserved resource is located is: the sum of the maximum duration (maximum value) of the currently configured extended cyclic prefix and the first duration, and the first duration is defined by the standard, configured by the network, or pre-configured. Exemplarily, the first duration can be used, for example, for a terminal (such as a second terminal) to receive and process the PSFCH.

[0171] Taking Figure 10 as an example, assuming that the reserved resource is located in time slot n, the starting time of the time slot where the reserved resource is located is recorded as t n The maximum duration of the currently configured extended cyclic prefix is ​​recorded as max(T ext ), the first duration is recorded as t PSFCH , then the first moment can be expressed as: t n -max(T ext )-t PSFCH As shown in Figure 10, the last PSFCH transmission opportunity before the first moment is the PSFCH transmission opportunity in time slot n-3. That is, the first PSFCH can be located in the PSFCH transmission opportunity in time slot n-3 (i.e., transmission opportunity #2) in the time domain. In this case, the first terminal can send the first PSFCH to the second terminal in PSFCH transmission opportunity #2, thereby instructing the second terminal to access the channel using a specified type of channel access method to use the reserved resources in time slot n.

[0172] According to the above technical solution, the first PSFCH can be located in the time domain at the last PSFCH transmission opportunity before the first moment. In this way, the problem of the second terminal being unable to determine whether it can access the channel through the specified type of channel access method to use the reserved resources can be avoided because it does not have time to decode the first PSFCH.

[0173] In some embodiments, the first PSFCH is located in the frequency domain at: a first interleaved resource block in an interleaved resource block set; or a first common interleaved resource block and at least one dedicated PRB in a dedicated physical resource block PRB set.

[0174] In one example, the first PSFCH is located in the first interleaved resource block in the set of interleaved resource blocks in the frequency domain.

[0175] In some embodiments, the interleaved resource blocks in the interleaved resource block set do not overlap with the interleaved resource blocks used to send the second PSFCH, and the second PSFCH includes: a PSFCH for feedback of HARQ-ACK (i.e., a PSFCH for carrying HARQ-ACK feedback) and a PSFCH for indicating resource conflicts (i.e., a PSFCH for conflicting resource indication). In other words, the interleaved resource blocks in the interleaved resource block set do not overlap with the interleaved resource blocks of the PSFCH for feedback of HARQ-ACK, and do not overlap with the interleaved resource blocks of the PSFCH for indicating resource conflicts. In some embodiments, the interleaved resource block set can be preconfigured or configured by first signaling, and the first signaling can be sent by the network to the first terminal, for example.

[0176] In another example, the first PSFCH is located in the frequency domain in: a first common interlace resource block and at least one (eg, N) dedicated PRBs in a dedicated PRB set.

[0177] In some embodiments, the first common interleaved resource block is the same as the common interleaved resource block used to send the second PSFCH. That is, the first common interleaved resource block is the same as the common interleaved resource block used to feedback the PSFCH for HARQ-ACK, and is the same as the common interleaved resource block used to indicate a resource conflict.

[0178] In some embodiments, the dedicated PRB set does not overlap with the PRB set used to transmit the second PSFCH. That is, the dedicated PRB set does not overlap with the PRB set used to transmit the HARQ-ACK feedback PSFCH, and does not overlap with the PRB set used to transmit the PSFCH indicating resource conflicts. In some embodiments, the dedicated PRB set may be preconfigured or configured by second signaling, which may be sent by the network to the first terminal, for example.

[0179] In some embodiments, the first PSFCH is located in the time domain at: a plurality of PSFCH transmission opportunities.

[0180] Among the multiple PSFCH transmission opportunities, the time interval between two adjacent PSFCH transmission opportunities is the first time interval, and the last PSFCH transmission opportunity among the multiple PSFCH transmission opportunities is: the last PSFCH transmission opportunity before the reserved resources; or, the last PSFCH transmission opportunity before the first moment; wherein, the first moment is before the time slot where the reserved resources are located, and the time interval between the first moment and the starting moment of the time slot where the reserved resources are located is: the sum of the maximum duration of the currently configured extended cyclic prefix and the first duration, and the first duration is defined by the standard, configured by the network, or pre-configured.

[0181] For example, assuming that the first PSFCH is located in M ​​(M is greater than 1) PSFCH transmission opportunities in the time domain, and the time slot where the last PSFCH transmission opportunity among the M PSFCH transmission opportunities is located is, for example, time slot k, then the time slots where the M PSFCH transmission opportunities are located can be expressed as k-(m-1)*P, where m=1, 2, ..., M, and P is the first time interval.

[0182] For example, in FIG10 , assuming that M=3 and the first time interval P is 2 time slots, in this case, if the last PSFCH transmission opportunity among the M PSFCH transmission opportunities is the last PSFCH transmission opportunity before the reserved resources, that is, the PSFCH transmission opportunity in time slot n-1 (that is, k=n-1), then the time slots in which the M PSFCH transmission opportunities are located are time slots n-1, n-3, and n-5, respectively. In other words, the M PSFCH transmission opportunities are the PSFCH transmission opportunity in time slot n-1 (that is, PSFCH transmission opportunity #3), the PSFCH transmission opportunity in time slot n-3 (that is, PSFCH transmission opportunity #2), and the PSFCH transmission opportunity in time slot n-5 (that is, PSFCH transmission opportunity #1). Similarly, if the last of the M PSFCH transmission opportunities is the last PSFCH transmission opportunity before the first moment, i.e., the PSFCH transmission opportunity in time slot n-3 (i.e., k=n-3), then the time slots in which the M PSFCH transmission opportunities are located are time slots n-3, n-5, and n-7, respectively. In other words, the M PSFCH transmission opportunities are the PSFCH transmission opportunity in time slot n-3 (i.e., PSFCH transmission opportunity #2), the PSFCH transmission opportunity in time slot n-5 (i.e., PSFCH transmission opportunity #1), and the PSFCH transmission opportunity in time slot n-7 (not shown in FIG. 10 ).

[0183] In some embodiments, the first time interval P may be configured, preconfigured, or predefined by the network (eg, predefined by a protocol).

[0184] According to the above technical solution, the first PSFCH can be located in multiple PSFCH transmission opportunities in the time domain. That is, the first terminal can send the first PSFCH to the second terminal on multiple PSFCH transmission opportunities, which helps to avoid failure in the transmission of the first PSFCH. It can be understood that when the first terminal sends the first PSFCH to the second terminal on multiple PSFCH transmission opportunities, if the second terminal receives the first PSFCH on at least one of the PSFCH transmission opportunities, it can access the channel using a specified type of channel access method to use the reserved resources of the second terminal.

[0185] In some embodiments, when a first terminal sends a first PSFCH to a second terminal on multiple PSFCH transmission opportunities, for any PSFCH transmission opportunity among the multiple PSFCH transmission opportunities, the first PSFCH on the PSFCH transmission opportunity is located in the frequency domain: the first interleaved resource block in the interleaved resource block set corresponding to the PSFCH transmission opportunity; or, the first common interleaved resource block corresponding to the PSFCH transmission opportunity, and at least one dedicated PRB in the dedicated PRB set corresponding to the PSFCH transmission opportunity.

[0186] In one example, the first PSFCH in the PSFCH transmission opportunity is located in the frequency domain at: the first interleaved resource block in the interleaved resource block set corresponding to the PSFCH transmission opportunity.

[0187] In some embodiments, the interleaved resource blocks in the interleaved resource block set corresponding to the PSFCH transmission opportunity do not overlap with the interleaved resource blocks used to send the second PSFCH, and the second PSFCH includes: a PSFCH for feedback of HARQ-ACK and a PSFCH for indicating resource conflicts. That is, the interleaved resource blocks in the interleaved resource block set do not overlap with the interleaved resource blocks of the PSFCH for feedback of HARQ-ACK, and do not overlap with the interleaved resource blocks of the PSFCH for indicating resource conflicts. In some embodiments, the interleaved resource block set can be preconfigured or configured by first signaling, and the first signaling can be sent by the network to the first terminal, for example.

[0188] In another example, the first PSFCH on the PSFCH transmission opportunity is located in the frequency domain: the first common interleaved resource block corresponding to the PSFCH transmission opportunity, and at least one dedicated PRB in the dedicated PRB set corresponding to the PSFCH transmission opportunity

[0189] In some embodiments, the first common interleaved resource block corresponding to the PSFCH transmission opportunity is the same as the common interleaved resource block used to send the second PSFCH. In other words, the first common interleaved resource block is the same as the common interleaved resource block used to feedback the PSFCH for HARQ-ACK, and is the same as the common interleaved resource block occupied by the PSFCH used to indicate resource conflicts.

[0190] In some embodiments, the dedicated PRB set corresponding to the PSFCH transmission opportunity does not overlap with the PRB set used to transmit the second PSFCH. That is, the dedicated PRB set does not overlap with the PRB set of the PSFCH used to feedback HARQ-ACK, and does not overlap with the PRB set of the PSFCH used to indicate resource conflicts. In some embodiments, the dedicated PRB set can be pre-configured or configured by second signaling, which can be sent by the network to the first terminal, for example.

[0191] In some embodiments, the method may further include: the second terminal receiving first indication information, the first indication information being used to indicate that a resource conflict occurs on the reserved resources of the second terminal. Exemplarily, the first indication information may be a PSFCH sent by the first terminal to indicate the resource conflict.

[0192] In one possible embodiment, when the second terminal receives the first indication information earlier than the first PSFCH, the method may further include: the second terminal accesses the channel through a specified type of channel access method to use the reserved resources of the second terminal; when the first indication information is received later than the first PSFCH, the method may further include: the second terminal reselects the reserved resources.

[0193] It is understandable that if the second terminal receives the first indication information earlier than the first PSFCH, then when the second terminal receives the first PSFCH, the resource conflict on the reserved resources may no longer exist, so the second terminal can continue to access the channel through the specified type of channel access method to use the second terminal's reserved resources. If the second terminal receives the first indication information later than the first PSFCH, the second terminal needs to reselect the reserved resources to avoid resource conflicts.

[0194] In another possible embodiment, when the second terminal receives the first indication information, the method may further include: the second terminal reselecting the reserved resource. In other words, regardless of whether the second terminal receives the first indication information earlier than the first PSFCH, the second terminal needs to reselect the reserved resource to minimize the possibility of resource conflict.

[0195] In some embodiments, the resources (time-frequency resources) occupied by the first PSFCH are the same as the resources (time-frequency resources) occupied by the PSFCH used to indicate resource conflict, and the sequence cyclic shift (Sequence Cyclic Shift) of the first PSFCH is different from the sequence cyclic shift of the PSFCH used to indicate resource conflict.

[0196] That is, the first terminal may send a first PSFCH to the second terminal on a PSFCH resource used to indicate a resource conflict. In this case, to avoid a conflict between the first PSFCH and the PSFCH used to indicate a resource conflict, the sequence cyclic shift of the first PSFCH must not be equal to the sequence cyclic shift of the PSFCH used to indicate the resource conflict. For example, since the sequence cyclic shift of the PSFCH currently used to indicate a resource conflict is 0, in this case, the sequence cyclic shift of the first PSFCH should not be equal to 0. In some embodiments, the sequence cyclic shift of the first PSFCH may be equal to 6.

[0197] In some embodiments, the first terminal sending the first PSFCH to the second terminal includes: if the first terminal satisfies a first condition, the first terminal sending the first PSFCH to the second terminal. In other words, the first terminal sending the first PSFCH to the second terminal is premised on satisfying the first condition.

[0198] For example, the first condition may include at least one of the following conditions A to F:

[0199] Condition A: The moment when the first terminal generates the COT is before the PSFCH transmission opportunity where the first PSFCH is located, and the duration of the COT includes the time slot where the reserved resources are located.

[0200] Condition B: The value of the Channel Access Priority Class (CAPC) used by the first terminal to generate the COT is greater than or equal to the first value.

[0201] In one example, the value of the CAPC used by the first terminal to generate the COT is equal to the first value. For example, the first value may be 4. In this case, the second terminal sharing the COT takes a relatively long time to perform channel access (or LBT), consuming more energy. Therefore, the first terminal may instruct the second terminal to access the channel using a specified type of channel access method through the first PSFCH in this case, thereby reducing the energy consumption of the second terminal performing channel access (or LBT).

[0202] In another example, the value of the CAPC used by the first terminal to generate the COT is greater than the first value. In this case, the first value may be indicated by the second terminal, for example. For example, the second terminal may indicate the first value via the SCI or the Media Access Control (MAC) control element (MAC CE) when indicating the reserved resources. The first value may be, for example, the CAPC for the second terminal to send data on the reserved resources.

[0203] Condition C: The first terminal is a target receiving terminal to which the second terminal will send data on the reserved resources.

[0204] Condition D: The target identifier indicated in the SCI used to indicate the reserved resources is the identifier of the first terminal.

[0205] Condition E: A unicast connection exists between the first terminal and the second terminal.

[0206] Condition F: The second terminal does not meet the condition for indicating a resource conflict to the first terminal during the PSFCH transmission opportunity where the first PSFCH is located. It is understandable that if the first terminal indicates a resource conflict to the second terminal during the PSFCH transmission opportunity where the first PSFCH is located, the second terminal needs to perform resource reselection and cannot use the second terminal's reserved resources. Therefore, the second terminal may send the first PSFCH when condition F is met, thereby instructing the second terminal to access the channel through a specified type of channel access method to use the second terminal's reserved resources.

[0207] In some embodiments, the resources occupied by the first PSFCH are associated with the reserved resources of the second terminal. That is, the first terminal may send the first PSFCH to the second terminal on the PSFCH resources associated with the reserved resources, thereby instructing the second terminal to access the channel using a specified type of channel access method to use the reserved resources of the second terminal.

[0208] In some embodiments, the resources occupied by the first PSFCH are associated with a PSSCH sent by the second terminal to the first terminal, and the reserved resources of the second terminal are used for retransmission of the PSSCH. In other words, the first terminal may send the first PSFCH to the first terminal on the PSFCH resources associated with the PSSCH, thereby instructing the second terminal to access the channel using a specified type of channel access method, so as to use the reserved resources of the second terminal for retransmission of the PSSCH.

[0209] Exemplarily, when the first terminal fails to successfully decode the PSSCH and the first terminal satisfies the above-mentioned first condition, the first terminal may send a first PSFCH to the second terminal. In this case, the first PSFCH can be used to instruct the second terminal to access the channel through a specified type of channel access method to use the reserved resources of the second terminal, and can also be used to indicate NACK. For example, if the first terminal fails to successfully decode the PSSCH and the first terminal meets the above-mentioned first condition, then the first terminal may send a PSFCH (first PSFCH) with a sequence cyclic shift of 0 to the second terminal on the PSFCH resource associated with the PSSCH, i.e., indicating NACK. At the same time, the PSFCH with a sequence cyclic shift of 0 can also be used to instruct the second terminal to access the channel through a specified type of channel access method to use the reserved resources of the second terminal.

[0210] In some embodiments, if the first terminal successfully decodes the PSSCH, the first terminal may send a PSFCH with a sequence cyclic shift of 6 to the second terminal on the PSFCH resources associated with the PSSCH, indicating an ACK. In this case, the second terminal may not need to use reserved resources to retransmit the PSSCH.

[0211] In some embodiments, if the first terminal fails to successfully decode the PSSCH and the first terminal does not meet the first condition described above, the first terminal may not transmit the PSFCH on the PSFCH resources associated with the PSSCH. In this case, the second terminal cannot access the channel using the specified type of channel access method to use the second terminal's reserved resources.

[0212] In some embodiments, when the second terminal accesses the channel through a specified type of channel access method to use the reserved resources of the second terminal, the reserved resources can be used by the second terminal to send a side channel, and the target identifier of the side channel includes the identifier of the first terminal, and the identifier of the first terminal is the same as the target identifier indicated in the SCI used to indicate the reserved resources.

[0213] For example, after receiving the first PSFCH from the first terminal, the second terminal can access the channel using a specified type of channel access method and use the reserved resources of the second terminal to send a sidelink channel. The target identifier of the sidelink channel includes at least the target identifier indicated in the SCI used to indicate the reserved resources, and the target identifier is the identifier of the first terminal.

[0214] In some embodiments, the designated type is Type 2. In this case, the first PSFCH may be used to instruct the second terminal to access the channel through Type 2 channel access to use the reserved resources of the second terminal. In this way, the possibility of the second terminal accessing the channel through Type 2 channel access may be increased. When the second terminal accesses the channel through Type 2 channel access, the second terminal may not need to perform Type 1 channel access. Since the energy consumption of the Type 2 channel access process is lower than that of the Type 1 channel access process, this method is beneficial to reducing the energy consumption of the second terminal performing channel access.

[0215] FIG11 is a flow chart of a second embodiment of the channel access method provided in the present application. As shown in FIG10 , the method may include the following steps:

[0216] S1101, the first terminal sends inter-UE coordination (IUC) information to the second terminal, where the ICU information is used to indicate multiple transmission resources of the second terminal. The second terminal can access the channel through a specified type of channel access method to use part or all of the multiple transmission resources.

[0217] In this embodiment, the first terminal can send IUC information to the second terminal, and accordingly, the second terminal can receive IUC information from the first terminal. The ICU information can be used to indicate multiple transmission resources of the second terminal, and the second terminal can access the channel through a specified type of channel access method to use some or all of the multiple transmission resources.

[0218] In some embodiments, the IUC information is carried in a second-order SCI (e.g., SCI format 2-C). In this case, for any transmission resource among the multiple transmission resources, if the time interval between the time slot in which the transmission resource is located and the time slot in which the second-order SCI is located is less than the second time interval, the second terminal can access the channel using a specified type of channel access method to use the transmission resource.

[0219] For example, the second time interval may be the maximum number of time slots included in the remaining time of the COT generated by the first terminal, and the first terminal may share the COT with the second terminal. For example, assuming that the second time interval is recorded as Z, then Z can be determined as follows: Z = 8·2 μ -2 or Z = 10·2 μ -2. 8 or 10 represents the maximum possible duration for generating the COT, in ms, μ represents the subcarrier spacing index of the current carrier, and 2 represents the total number of time slots occupied by the second-order SCI (SCI format 2-C) and a transmission resource. According to the method of this embodiment, for any transmission resource among multiple transmission resources, if the time interval between the time slot where the transmission resource is located and the time slot where the second-order SCI is located is less than the second time interval Z, it means that the transmission resource is within the COT generated by the first terminal, so the first terminal can access the channel through a specified type of channel access method to use the transmission resource.

[0220] In some embodiments, the ICU information includes multiple TRIVs, each TRIV is used to indicate the transmission resources of the second terminal over multiple time slots. For example, the ICU information may include multiple (such as 2) {TRIV, FRIV, reservation period} combinations, each combination containing a TRIV, which can indicate the transmission resources of the second terminal over multiple time slots. In this case, the second terminal can access the channel through a specified type of channel access method to use the first transmission resource and the transmission resource before the time slot where the first transmission resource is located. The first transmission resource is: the transmission resource on the last time slot indicated by the last TRIV in multiple TRIVs; or, the transmission resource on the last time slot indicated by the first TRIV in multiple TRIVs.

[0221] In one example, the first transmission resource is the transmission resource on the last time slot indicated by the last TRIV in multiple TRIVs. For example, if the ICU information contains two {TRIV, FRIV, reservation period} combinations, then the last TRIV in the multiple TRIVs is the TRIV in the second {TRIV, FRIV, reservation period} combination (for example, recorded as the first TRIV). In this case, the second terminal can access the channel through a specified type of channel access method to use the transmission resource on the last time slot indicated by the first TRIV, as well as the transmission resources before the last time slot.

[0222] In another example, the first transmission resource is the transmission resource on the last time slot indicated by the first TRIV in multiple TRIVs. For example, if the ICU information contains two {TRIV, FRIV, reservation period} combinations, then the first TRIV in the multiple TRIVs is the TRIV in the first {TRIV, FRIV, reservation period} combination (for example, recorded as the second TRIV). In this case, the second terminal can access the channel through a specified type of channel access method to use the transmission resource on the last time slot indicated by the second TRIV, as well as the transmission resource before the last time slot.

[0223] In some embodiments, the first transmission resource and the transmission resource preceding the time slot in which the first transmission resource is located are included in the COT generated by the first terminal. For example, when the first terminal sends ICU information to the second terminal, it is necessary to ensure that the first transmission resource indicated by the ICU information and the transmission resource preceding the time slot in which the first transmission resource is located are both included in the COT generated by the first terminal. Thus, after receiving the ICU information, the second terminal can access the channel through a specified type of channel access method to use the first transmission resource and the transmission resource preceding the time slot in which the first transmission resource is located.

[0224] In some embodiments, the IUC information is carried in a MAC CE. In this case, the MAC CE may include second indication information, which is used to indicate that the second terminal can access the channel through a specified type of channel access method to use some or all of the multiple transmission resources.

[0225] For example, when a first terminal sends IUC information to a second terminal via a MAC CE, a specific field may be added to the MAC CE to indicate that the second terminal can access the channel using a specified type of channel access method to use some or all of the multiple transmission resources indicated by the IUC information. For example, the specific field may indicate that the second terminal can access the channel using the specified type of channel access method to use the second transmission resource indicated by the IUC information, and the second transmission resource may be some or all of the transmission resources indicated by the IUC information.

[0226] According to the method of this embodiment, the first terminal can send IUC information to the second terminal, and the second terminal can access the channel through a specified type of channel access method to use some or all of the multiple transmission resources indicated by the IUC information. In this way, the possibility of the second terminal accessing the channel through a specified type of channel access method can be increased. When the second terminal accesses the channel through a specified type of channel access method, the second terminal may not need to perform type 1 channel access. Since the energy loss of the type 1 channel access process is relatively high, this method is beneficial to reducing the energy loss of the second terminal performing channel access.

[0227] In some embodiments, the designated type is Type 2. When the second terminal accesses the channel using Type 2 channel access, the second terminal may not need to perform Type 1 channel access. Since the energy consumption of the Type 2 channel access process is lower than that of the Type 1 channel access process, this method is beneficial for reducing the energy consumption of the second terminal performing channel access.

[0228] The above describes the channel access method provided in the embodiments of the present application. To facilitate understanding of the embodiments of the present application, the following describes possible implementations of the channel access method applicable to the embodiments of the present application, using Type 2 as an example. For simplicity, in the following examples, the first terminal is referred to as Terminal #1, and the second terminal is referred to as Terminal #2.

[0229] Option 1

[0230] In solution 1, the reserved resources of terminal #2 are associated with dedicated PSFCH resources. Terminal #1 can indicate on the PSFCH resources whether terminal #2 can access the channel through Type 2 mode (channel access mode of Type 2) to use the reserved resources.

[0231] That is, terminal #1 can indicate on the PSFCH resource corresponding to (associated with) the reserved resources of terminal #2 whether terminal #2 can access the channel in a Type 2 manner and thus use the next reserved resources. For example, terminal #1 can send a PSFCH (i.e., the first PSFCH in the aforementioned embodiment) to terminal #2 on this PSFCH resource. This PSFCH can be used to indicate that terminal #2 can access the channel in a Type 2 manner and use the reserved resources of terminal #2.

[0232] As an example, the PSFCH may occupy, in the frequency domain, one interleaved resource block (e.g., a dedicated interleaved resource block). The set of interleaved resource blocks that may be used to transmit the PSFCH may be configured or preconfigured, for example, by separate signaling. In some embodiments, the interleaved resource blocks included in the interleaved resource block set do not overlap with the interleaved resource blocks used to carry the PSFCH for HARQ-ACK feedback and conflicting resource indication.

[0233] As another example, the PSFCH can occupy one common interleaved resource block and N dedicated PRBs in the frequency domain. In some embodiments, the common interleaved resource block used to transmit the PSFCH is the same as the common interleaved resource block used to carry HARQ-ACK feedback and the PSFCH for conflicting resource indication. The PRB set to which the N dedicated PRBs belong (dedicated PRB set) can be configured or pre-configured by separate signaling, for example. In some embodiments, the PRB set does not overlap with the PRB set used to carry the PSFCH for HARQ-ACK feedback and conflicting resource indication.

[0234] As an example, for a reserved resource in timeslot n, the preferred transmission opportunity for the PSFCH (first PSFCH) indicating the Type 2 channel access mode corresponding to the reserved resource can be the PSFCH transmission opportunity in timeslot m. Timeslot m satisfies the requirement that it is the last timeslot before timeslot n that contains a PSFCH resource. For example, in Figure 10 , the preferred transmission opportunity for the PSFCH is the PSFCH transmission opportunity in timeslot n-1 (i.e., PSFCH transmission opportunity #3).

[0235] As another example, for the reserved resources on time slot n, the preferred transmission opportunity of the PSFCH (first PSFCH) corresponding to the reserved resources for indicating the Type 2 channel access mode may be: the OFDM symbol end point is at t n -max(T ext )-t PSFCH The last PSFCH transmission opportunity before t n Indicates the starting time of time slot n; max(T ext ) represents the maximum value of the currently configured extended cyclic prefix; tPSFCH "represents a time interval (i.e., the first duration in the aforementioned embodiment) that can be used by the terminal to receive and process the PSFCH. The value of this time interval can be, for example, defined by network configuration, pre-configuration, or a standard. For example, in Figure 10 , the preferred transmitter for the PSFCH is the PSFCH transmission opportunity in time slot n-3 (i.e., PSFCH transmission opportunity #2).

[0236] It should be noted that a PSFCH transmission opportunity refers to one or more consecutive OFDM symbols containing PSFCH resources. For example, in Figure 10, three PSFCH transmission opportunities are shown, namely PSFCH transmission opportunity #1, PSFCH transmission opportunity #2, and PSFCH transmission opportunity #3.

[0237] In some embodiments, each reserved resource for terminal #2 may be associated with (correspond to) M PSFCH transmission opportunities for indicating a Type 2 channel access mode. In this case, terminal #1 may send a PSFCH to terminal #2 on these M PSFCH transmission opportunities, thereby indicating that terminal #2 can access the channel using the Type 2 mode to use the reserved resource.

[0238] Exemplarily, assuming that the time slot where the preferred PSFCH transmission opportunity is located is k, then the time slots where the M transmission opportunities are located are k-(m-1)*P. Wherein, P is the time interval between adjacent PSFCH transmission opportunities, and the value of the time interval can be defined by, for example, network configuration, pre-configuration or standard. Wherein, m=1,2,…,M. For example, in Figure 10, assuming that the time slot where the preferred PSFCH transmission opportunity is located is n-1, then the reserved resources on time slot n can be associated with, for example, 3 PSFCH transmission opportunities for indicating Type 2 channel access mode, namely PSFCH transmission opportunity #1, PSFCH transmission opportunity #2 and PSFCH transmission opportunity #3, wherein the time interval P between adjacent PSFCH transmission opportunities is 2 time slots.

[0239] In some embodiments, if Terminal #2 receives a PSFCH indicating a Type 2 channel access mode, Terminal #2 may access the channel using a Type 2 mode and then transmit a sidelink channel on the reserved resources corresponding to the PSFCH. The target ID of the sidelink channel should include at least the target ID indicated in the SCI indicating the reserved resources.

[0240] In some embodiments, for a specific reserved resource of terminal #2, if terminal #2 receives both a resource conflict indication (used to indicate that a resource conflict occurs on the reserved resource) and a Type 2 channel access indication (such as receiving a PSFCH used to indicate a Type 2 channel access mode), terminal #2 may implement the following schemes:

[0241] Method 1: If Terminal #2 receives the Type 2 channel access indication later than the resource conflict indication, the resource conflict may no longer exist, so Terminal #2 can continue to use the reserved resources through Type 2 channel access. Otherwise, Terminal #2 should reselect the reserved resources.

[0242] Method 2: Terminal #2 should reselect the reserved resources to minimize the possibility of resource conflict.

[0243] In some embodiments, when terminal #1 satisfies at least one of the following conditions a) to e) (corresponding to the first condition in the aforementioned embodiment), terminal #1 may indicate on a certain PSFCH transmission opportunity whether terminal #2 can access the channel via Type 2 to use the reserved resources associated with the PSFCH transmission opportunity.

[0244] a) During or before the PSFCH transmission opportunity, the duration of the COT generated by terminal #1 includes the time slot where the reserved resource is located.

[0245] b) The CAPC value used by Terminal #1 to generate the COT is 4, or is greater than a CAPC value Y. The value of Y may be indicated by Terminal #2, for example, Terminal #2 may indicate the value of Y through an SCI or MAC CE when indicating the reserved resources. Y may be the CAPC for Terminal #2 to send data on the reserved resources.

[0246] c) Terminal #1 is the target receiving terminal to which Terminal #2 will send data on the reserved resources, or the target ID indicated in the SCI indicating the reserved resources corresponds to Terminal #1 (or the target ID is the ID of Terminal #1).

[0247] d) There is a unicast connection between terminal #1 and terminal #2.

[0248] e) In this PSFCH transmission opportunity, terminal #1 does not meet the conditions for sending a resource conflict indication (Conflict Information) to terminal #2.

[0249] Option 2

[0250] In solution 2, terminal #1 can indicate to terminal #2 on the PSFCH resources used to indicate resource conflict or HARQ-ACK feedback whether it can access the channel via Type 2 to use the reserved resources of terminal #2.

[0251] In the first possible approach, terminal #1 may indicate, on the PSFCH resource corresponding to terminal #2's reserved resources, whether terminal #2 may access the channel in a Type 2 manner to use the reserved resources. For example, terminal #1 may send a PSFCH (i.e., the first PSFCH in the aforementioned embodiment) to terminal #2 on the PSFCH resource. The PSFCH may be used to indicate to terminal #2 that terminal #2 may access the channel in a Type 2 manner to use the reserved resources.

[0252] In some embodiments, the PSFCH time-frequency resources occupied by the PSFCH are the same as the time-frequency resources occupied by the PSFCH used for resource conflict indication, but the cyclic shift (Sequence Cyclic Shift) of the PSFCH sequence used to indicate the Type 2 channel access mode should not be equal to 0. In some embodiments, it may be equal to 6.

[0253] In some embodiments, when terminal #2 does not send a PSFCH for indicating Type 2 channel access mode to terminal #2 on the PSFCH resource, terminal #2 may send a PSFCH for resource conflict indication to terminal #2 on the PSFCH resource to indicate that there is a resource conflict on the reserved resources.

[0254] In the second possible approach, terminal #1 can indicate to terminal #2 on the PSFCH resource for HARQ-ACK feedback corresponding to the PSSCH currently transmitted by terminal #2 whether it can access the channel via Type 2 to use the next reserved resource, which can be used for retransmission of the PSSCH. For this approach:

[0255] In one possible scenario, if terminal #1 successfully decodes the current PSSCH, it can send a PSFCH with a sequence cyclic shift of 6, i.e., ACK, on ​​the PSFCH resource. In this case, terminal #2 does not need to use the next reserved resource to retransmit the PSSCH.

[0256] In another possible scenario, if Terminal #1 fails to successfully decode the current PSSCH and Terminal #1 meets the conditions for indicating to Terminal #2 that the next reserved resource can access the channel via Type 2 (such conditions may be, for example, at least one of the above conditions a) to e)), Terminal #1 may send a PSFCH with a sequence cyclic shift of 0 on the PSFCH resource, i.e., indicate a NACK, and the next reserved resource can access the channel via Type 2. In this case, after receiving the PSFCH with a sequence cyclic shift of 0, Terminal #2 can access the channel via Type 2 and use the reserved resource to retransmit the PSSCH.

[0257] In another possible scenario, if terminal #1 fails to successfully decode the current PSSCH and terminal #1 does not meet the conditions for indicating to terminal #2 that the next reserved resource can access the channel via Type 2, terminal #1 should not send PSFCH on the PSFCH resource.

[0258] Option 3

[0259] In solution 3, terminal #1 can indicate a resource set suitable for terminal #2 through IUC information. Terminal #2 can access the channel through Type 2 to use some or all of the resources in the resource set.

[0260] In a first possible approach, IUC information may be carried in SCI format 2-C (or simply SCI 2-C). Terminal #1 may send a resource set suitable for use by Terminal #2 to Terminal #2 via SCI format 2-C. The SCI format 2-C may include two {TRIV, FRIV, reservation period} combinations, where some or all of the resources indicated in at least one combination can access the channel via Type 2. In other words, Terminal #2 can access the channel via Type 2 and thereby use some or all of the resources indicated in the at least one combination.

[0261] As an example, for any resource indicated by each {TRIV, FRIV, reservation period} combination in SCI format 2-C, if the interval between the resource and the time slot where the SCI format 2-C is located is less than Z, terminal #2 can use the resource by accessing the channel in Type 2 mode.

[0262] Here, Z represents the maximum value of the time slots included in the remaining time of the shared COT by terminal #1. For example, Z = 8·2 μ -2 or Z = 10·2 μ -2, 8 or 10 indicates the maximum possible duration of generating COT, in ms, μ indicates the subcarrier spacing index of the current carrier, and 2 indicates the total number of time slots occupied by SCI format 2-C and resources.

[0263] As another example, among the resources indicated by the combination of {TRIV, FRIV, reservation period} included in SCI format 2-C, the resources in the last time slot indicated by the last TRIV, as well as the resources before the last time slot, can both access the channel via Type 2. In some embodiments, Terminal #1 should ensure that the resources in the last time slot, as well as the resources before the last time slot, are included in the COT generated by Terminal #1.

[0264] As another example, the resources in the last time slot indicated by the first TRIV of {TRIV, FRIV, reservation period} included in SCI format 2-C, as well as the resources before the last time slot, can all be accessed via Type 2. In some embodiments, terminal #1 should ensure that the resources in the last time slot, as well as the resources before the last time slot, are included in the COT generated by terminal #1.

[0265] In a second possible approach, the IUC information can be carried in a MAC CE. When Terminal #1 sends the IUC information to Terminal #2 via a MAC CE, it can add a specific field to the MAC CE to indicate whether Terminal #2 can access the channel via Type 2 to use some or all of the resources indicated by the IUC information. For example, this specific field can indicate that Terminal #2 can access the channel via Type 2 to use the second transmission resource indicated by the IUC information, which can be some or all of the resources indicated by the IUC information.

[0266] According to the above solutions 1 to 3, Terminal #1 can instruct Terminal #2 via PSFCH to access the channel using Type 2 to use the next reserved resources. Alternatively, Terminal #1 can also indicate (indirectly or directly) when sending IUC information to Terminal #2 whether Terminal #2 can use some or all of the resources indicated in the IUC information using Type 2 channel access. This increases the likelihood of Terminal #2 accessing the channel using Type 2 channel access and reduces the energy consumption of Terminal #2 performing LBT.

[0267] The preferred embodiments of the present application are described in detail above in conjunction with the accompanying drawings. However, the present application is not limited to the specific details in the above embodiments. Within the technical concept of the present application, the technical solution of the present application can be subjected to a variety of simple modifications, and these simple modifications all fall within the scope of protection of the present application. For example, the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present application will no longer describe the various possible combinations separately. For another example, the various different embodiments of the present application can also be arbitrarily combined, as long as they do not violate the idea of ​​the present application, they should also be regarded as the contents disclosed in the present application. For another example, under the premise of no conflict, the various embodiments and / or the technical features in each embodiment described in the present application can be arbitrarily combined with the prior art, and the technical solution obtained after the combination should also fall within the scope of protection of the present application.

[0268] It should also be understood that in the various method embodiments of the present application, the sequence numbers of the above-mentioned processes do not imply a precedence in the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application. In addition, in the embodiments of the present application, the terms "downlink," "uplink," and "sidelink" are used to indicate the transmission direction of signals or data, where "downlink" is used to indicate the first direction of transmission of signals or data from a site to a user equipment in a cell, "uplink" is used to indicate the second direction of transmission of signals or data from a user equipment in a cell to a site, and "sidelink" is used to indicate the third direction of transmission of signals or data from user equipment 1 to user equipment 2. For example, "downlink signal" indicates that the transmission direction of the signal is the first direction. In addition, in the embodiments of the present application, the term "and / or" is merely a description of the association relationship between associated objects, indicating that three relationships can exist. Specifically, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0269] Based on the aforementioned embodiments, the embodiments of the present application provide corresponding channel access devices.

[0270] FIG12 is a schematic diagram of the structure of a channel access device provided in an embodiment of the present application, which is applied to a first terminal. As shown in FIG12 , a channel access device 1200 (hereinafter referred to as device 1200 ) includes:

[0271] The first sending unit 1201 is configured to send a first physical sidelink feedback channel PSFCH to the second terminal, where the first PSFCH is used to instruct the second terminal to access the channel through a specified type of channel access method to use the reserved resources of the second terminal.

[0272] In some embodiments, the first PSFCH is located in the time domain at: the last PSFCH transmission opportunity before the reserved resources; or, the last PSFCH transmission opportunity before the first moment; wherein the first moment is before the time slot where the reserved resources are located, and the time interval between the first moment and the start moment of the time slot where the reserved resources are located is: the sum of the maximum duration of the currently configured extended cyclic prefix and the first duration, and the first duration is defined by the standard, configured by the network, or pre-configured.

[0273] In some embodiments, the first PSFCH is located in the frequency domain at: a first interleaved resource block in an interleaved resource block set; or a first common interleaved resource block and at least one dedicated PRB in a dedicated physical resource block PRB set.

[0274] In some embodiments, the first PSFCH is located in the time domain at: multiple PSFCH transmission opportunities; among the multiple PSFCH transmission opportunities, the time interval between two adjacent PSFCH transmission opportunities is the first time interval, and the last PSFCH transmission opportunity among the multiple PSFCH transmission opportunities is: the last PSFCH transmission opportunity before the reserved resources; or, the last PSFCH transmission opportunity before the first moment; wherein the first moment is before the time slot where the reserved resources are located, and the time interval between the first moment and the start moment of the time slot where the reserved resources are located is: the sum of the maximum duration of the currently configured extended cyclic prefix and the first duration, and the first duration is defined by the standard, configured by the network, or pre-configured.

[0275] In some embodiments, the first time interval is configured, preconfigured, or predefined by the network.

[0276] In some embodiments, for any PSFCH transmission opportunity among multiple PSFCH transmission opportunities, the first PSFCH on the PSFCH transmission opportunity is located in the frequency domain at: the first interleaved resource block in the interleaved resource block set corresponding to the PSFCH transmission opportunity; or, the first common interleaved resource block corresponding to the PSFCH transmission opportunity, and at least one dedicated PRB in the dedicated PRB set corresponding to the PSFCH transmission opportunity.

[0277] In some embodiments, the interleaved resource blocks in the interleaved resource block set and the interleaved resource blocks used to send the second PSFCH do not overlap; the dedicated PRB set and the PRB set used to send the second PSFCH do not overlap; the first public interleaved resource block and the public interleaved resource block used to send the second PSFCH are the same; wherein the second PSFCH includes: a PSFCH for feedback of a hybrid automatic repeat request-acknowledgement HARQ-ACK, and a PSFCH for indicating resource conflicts.

[0278] In some embodiments, the interleaved resource block set is preconfigured or configured by first signaling; and the dedicated PRB set is preconfigured or configured by second signaling.

[0279] In some embodiments, resources occupied by the first PSFCH are the same as resources occupied by the PSFCH used to indicate resource conflict, and a sequence cyclic shift of the first PSFCH is different from a sequence cyclic shift of the PSFCH used to indicate resource conflict.

[0280] In some embodiments, the first sending unit 1201 is specifically configured to: send the first PSFCH to the second terminal when the device 1200 meets the first condition.

[0281] In some embodiments, resources occupied by the first PSFCH are associated with reserved resources.

[0282] In some embodiments, resources occupied by the first PSFCH are associated with a physical sidelink shared channel PSSCH from the second terminal, and resources are reserved for retransmission of the PSSCH.

[0283] In some embodiments, the first sending unit 1201 is specifically configured to: send a first PSFCH to the second terminal when the device 1200 fails to decode the PSSCH and the device 1200 meets the first condition; the first PSFCH is also used to indicate a negative acknowledgement NACK.

[0284] In some embodiments, the first condition includes at least one of the following: the moment when the device 1200 generates the channel occupancy time COT is before the PSFCH transmission opportunity where the first PSFCH is located, and the duration of the COT includes the time slot where the reserved resources are located; the value of the channel access priority used by the device 1200 to generate the COT is greater than or equal to the first value; the device 1200 is the target receiving terminal to which the second terminal will send data on the reserved resources; the target identifier indicated in the side control information SCI for indicating the reserved resources is the identifier of the device 1200; there is a unicast connection between the device 1200 and the second terminal; in the PSFCH transmission opportunity where the first PSFCH is located, the second terminal does not meet the conditions for indicating a resource conflict to the device 1200.

[0285] In some embodiments, when the second terminal accesses the channel through a specified type of channel access method to use the reserved resources of the second terminal, the reserved resources are used for the second terminal to send a side channel, and the target identifier of the side channel includes the identifier of device 1200, and the identifier of device 1200 is the same as the target identifier indicated in the SCI used to indicate the reserved resources.

[0286] In some embodiments, the designated type is type 2.

[0287] FIG13 is a second schematic diagram of the structure of a channel access device provided in an embodiment of the present application, which is applied to a second terminal. As shown in FIG13 , a channel access device 1300 (hereinafter referred to as device 1300 ) includes:

[0288] The first receiving unit 1301 is configured to receive a first physical sidelink feedback channel PSFCH from the first terminal, where the first PSFCH is used to instruct the apparatus 1300 to access a channel through a specified type of channel access method to use reserved resources of the apparatus 1300 .

[0289] In some embodiments, the first PSFCH is located in the time domain at: the last PSFCH transmission opportunity before the reserved resources; or, the last PSFCH transmission opportunity before the first moment; wherein the first moment is before the time slot where the reserved resources are located, and the time interval between the first moment and the start moment of the time slot where the reserved resources are located is: the sum of the maximum duration of the currently configured extended cyclic prefix and the first duration, and the first duration is defined by the standard, configured by the network, or pre-configured.

[0290] In some embodiments, the first PSFCH is located in the frequency domain at: a first interleaved resource block in an interleaved resource block set; or a first common interleaved resource block and at least one dedicated PRB in a dedicated physical resource block PRB set.

[0291] In some embodiments, the first PSFCH is located in the time domain at: multiple PSFCH transmission opportunities; among the multiple PSFCH transmission opportunities, the time interval between two adjacent PSFCH transmission opportunities is the first time interval, and the last PSFCH transmission opportunity among the multiple PSFCH transmission opportunities is: the last PSFCH transmission opportunity before the reserved resources; or, the last PSFCH transmission opportunity before the first moment; wherein the first moment is before the time slot where the reserved resources are located, and the time interval between the first moment and the start moment of the time slot where the reserved resources are located is: the sum of the maximum duration of the currently configured extended cyclic prefix and the first duration, and the first duration is defined by the standard, configured by the network, or pre-configured.

[0292] In some embodiments, the first time interval is configured, preconfigured, or predefined by the network.

[0293] In some embodiments, for any PSFCH transmission opportunity among multiple PSFCH transmission opportunities, the first PSFCH on the PSFCH transmission opportunity is located in the frequency domain at: the first interleaved resource block in the interleaved resource block set corresponding to the PSFCH transmission opportunity; or, the first common interleaved resource block corresponding to the PSFCH transmission opportunity, and at least one dedicated PRB in the dedicated PRB set corresponding to the PSFCH transmission opportunity.

[0294] In some embodiments, the interleaved resource blocks in the interleaved resource block set and the interleaved resource blocks used to send the second PSFCH do not overlap; the dedicated PRB set and the PRB set used to send the second PSFCH do not overlap; the first public interleaved resource block and the public interleaved resource block used to send the second PSFCH are the same; wherein the second PSFCH includes: a PSFCH for feedback of a hybrid automatic repeat request-acknowledgement HARQ-ACK, and a PSFCH for indicating resource conflicts.

[0295] In some embodiments, the interleaved resource block set is preconfigured or configured by first signaling; and the dedicated PRB set is preconfigured or configured by second signaling.

[0296] In some embodiments, the apparatus 1300 further includes: a second receiving unit configured to receive first indication information, where the first indication information is used to indicate that a resource conflict occurs on the reserved resources.

[0297] In some embodiments, the device 1300 also includes: a channel access unit, configured to access the channel through a specified type of channel access method to use the reserved resources of the device 1300 when the moment of receiving the first indication information is earlier than the moment of receiving the first PSFCH; and a first reselection unit, configured to reselect the reserved resources when the moment of receiving the first indication information is later than the moment of receiving the first PSFCH.

[0298] In some embodiments, the apparatus 1300 further includes: a second reselection unit configured to reselect reserved resources.

[0299] In some embodiments, resources occupied by the first PSFCH are the same as resources occupied by the PSFCH used to indicate resource conflict, and a sequence cyclic shift of the first PSFCH is different from a sequence cyclic shift of the PSFCH used to indicate resource conflict.

[0300] In some embodiments, resources occupied by the first PSFCH are associated with reserved resources.

[0301] In some embodiments, resources occupied by the first PSFCH are associated with a physical sidelink shared channel PSSCH sent by the apparatus 1300 , and resources are reserved for retransmission of the PSSCH.

[0302] In some embodiments, the first PSFCH is also used to indicate a negative acknowledgement (NACK).

[0303] In some embodiments, when the device 1300 accesses the channel through a specified type of channel access method to use the reserved resources of the device 1300, the reserved resources are used for the device 1300 to send a side channel, and the target identifier of the side channel includes the identifier of the first terminal, and the identifier of the first terminal is the same as the target identifier indicated in the side control information SCI used to indicate the reserved resources.

[0304] In some embodiments, the designated type is type 2.

[0305] FIG14 is a third structural diagram of a channel access device provided in an embodiment of the present application, which is applied to a first terminal. As shown in FIG14 , a channel access device 1400 (hereinafter referred to as device 1400 ) includes:

[0306] The second sending unit 1401 is configured to send inter-terminal coordination IUC information to the second terminal, where the ICU information is used to indicate multiple transmission resources of the second terminal. The second terminal can access the channel through a specified type of channel access method to use some or all of the multiple transmission resources.

[0307] In some embodiments, the IUC information is carried in the second-order side control information SCI; for any transmission resource among multiple transmission resources, when the time interval between the time slot where the transmission resource is located and the time slot where the second-order SCI is located is less than the second time interval, the second terminal can access the channel through a specified type of channel access method to use the transmission resource.

[0308] In some embodiments, the second time interval is a maximum number of time slots included in the remaining time of the channel occupation time COT generated by the apparatus 1400 , and the COT is shared with the second terminal.

[0309] In some embodiments, the ICU information includes multiple time domain resource indication values ​​TRIV, each TRIV is used to indicate the transmission resources of the second terminal on multiple time slots, and the second terminal can access the channel through a specified type of channel access method to use the first transmission resource, as well as the transmission resource before the time slot where the first transmission resource is located; the first transmission resource is: the transmission resource on the last time slot indicated by the last TRIV among multiple TRIVs; or, the transmission resource on the last time slot indicated by the first TRIV among multiple TRIVs.

[0310] In some embodiments, the first transmission resource and the transmission resource before the time slot in which the first transmission resource is located are included in the COT generated by the apparatus 1400 , and the COT is shared with the second terminal.

[0311] In some embodiments, the IUC information is carried in a media access control element MAC CE; the MAC CE includes second indication information, and the second indication information is used to indicate that the second terminal can access the channel through a specified type of channel access method to use part or all of the multiple transmission resources.

[0312] In some embodiments, the designated type is type 2.

[0313] FIG15 is a fourth structural diagram of a channel access device provided in an embodiment of the present application, which is applied to a second terminal. As shown in FIG15 , a channel access device 1500 (hereinafter referred to as device 1500 ) includes:

[0314] The second receiving unit 1501 is configured to receive inter-terminal coordination IUC information from the first terminal, where the ICU information is used to indicate multiple transmission resources of the device 1500. The device 1500 can access the channel through a specified type of channel access method to use some or all of the multiple transmission resources.

[0315] In some embodiments, the IUC information is carried in the second-order side control information SCI; for any transmission resource among multiple transmission resources, when the time interval between the time slot where the transmission resource is located and the time slot where the second-order SCI is located is less than the second time interval, the device 1500 can access the channel through a specified type of channel access method to use the transmission resource.

[0316] In some embodiments, the second time interval is a maximum number of time slots included in the remaining time of the channel occupation time COT generated by the first terminal, and the COT is shared with the apparatus 1500 .

[0317] In some embodiments, the ICU information includes multiple time domain resource indication values ​​TRIV, each TRIV is used to indicate the transmission resources of the device 1500 on multiple time slots, and the device 1500 can access the channel through a specified type of channel access method to use the first transmission resource, as well as the transmission resource before the time slot where the first transmission resource is located; the first transmission resource is: the transmission resource on the last time slot indicated by the last TRIV among the multiple TRIVs; or, the transmission resource on the last time slot indicated by the first TRIV among the multiple TRIVs.

[0318] In some embodiments, the first transmission resource and the transmission resource before the time slot in which the first transmission resource is located are included in the COT generated by the first terminal, and the COT is shared with the apparatus 1500 .

[0319] In some embodiments, the IUC information is carried in a media access control element MAC CE; the MAC CE includes second indication information, which is used to indicate that the device 1500 can access the channel through a specified type of channel access method to use part or all of the multiple transmission resources.

[0320] In some embodiments, the designated type is type 2.

[0321] Those skilled in the art should understand that the relevant description of the above-mentioned channel access device in the embodiment of the present application can be understood with reference to the relevant description of the channel access method in the embodiment of the present application.

[0322] Figure 16 is a schematic structural diagram of a communication device 1600 provided in an embodiment of the present application. The communication device 1600 shown in Figure 16 includes a processor 1610, which can call and run a computer program from a memory to implement the method in the embodiment of the present application.

[0323] Optionally, as shown in FIG16 , the communication device 1600 may further include a memory 1620. The processor 1610 may call and execute a computer program from the memory 1620 to implement the method in the embodiment of the present application.

[0324] The memory 1620 may be a separate device independent of the processor 1610 , or may be integrated into the processor 1610 .

[0325] Optionally, as shown in FIG16 , the communication device 1600 may further include a transceiver 1630 , and the processor 1610 may control the transceiver 1630 to communicate with other devices, specifically, to send information or data to other devices, or to receive information or data sent by other devices.

[0326] The transceiver 1630 may include a transmitter and a receiver. The transceiver 1630 may further include an antenna, and the number of antennas may be one or more.

[0327] Optionally, the communication device 1600 may specifically be the first terminal of the embodiment of the present application, and the communication device 1600 may implement the corresponding processes implemented by the first terminal in each method of the embodiment of the present application. For the sake of brevity, they will not be repeated here.

[0328] Optionally, the communication device 1600 may specifically be the second terminal of the embodiment of the present application, and the communication device 1600 may implement the corresponding processes implemented by the second terminal in each method of the embodiment of the present application. For the sake of brevity, they will not be repeated here.

[0329] Figure 17 is a schematic structural diagram of a chip according to an embodiment of the present application. The chip 1700 shown in Figure 17 includes a processor 1710, which can call and run a computer program from a memory to implement the method according to the embodiment of the present application.

[0330] Optionally, as shown in FIG17 , the chip 1700 may further include a memory 1720. The processor 1710 may call and execute a computer program from the memory 1720 to implement the method in the embodiment of the present application.

[0331] The memory 1720 may be a separate device independent of the processor 1710 , or may be integrated into the processor 1710 .

[0332] Optionally, the chip 1700 may further include an input interface 1730. The processor 1710 may control the input interface 1730 to communicate with other devices or chips, and specifically, may obtain information or data sent by other devices or chips.

[0333] Optionally, the chip 1700 may further include an output interface 1740. The processor 1710 may control the output interface 1740 to communicate with other devices or chips, and specifically, may output information or data to other devices or chips.

[0334] Optionally, the chip can be applied to the first terminal in the embodiment of the present application, and the chip can implement the corresponding processes implemented by the first terminal in each method of the embodiment of the present application. For the sake of brevity, it will not be repeated here.

[0335] Optionally, the chip can be applied to the second terminal in the embodiment of the present application, and the chip can implement the corresponding processes implemented by the second terminal in each method of the embodiment of the present application. For the sake of brevity, it will not be repeated here.

[0336] It should be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

[0337] It should be understood that the processor of the embodiments of the present application may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method embodiment can be completed by hardware integrated logic circuits in the processor or software instructions. The above processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The various methods, steps, and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in the embodiments of the present application can be directly embodied as being executed by a hardware decoding processor, or can be executed by a combination of hardware and software modules in the decoding processor. The software module can be located in a storage medium mature in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, etc. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0338] It is understood that the memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct RAM bus random access memory (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0339] It should be understood that the above-mentioned memories are exemplary but not restrictive. For example, the memories in the embodiments of the present application may also be static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct RAM RAM (DR RAM), etc. In other words, the memories in the embodiments of the present application are intended to include, but are not limited to, these and any other suitable types of memories.

[0340] An embodiment of the present application also provides a computer-readable storage medium for storing a computer program.

[0341] Optionally, the computer-readable storage medium can be applied to the first terminal in the embodiment of the present application, and the computer program enables the computer to execute the corresponding processes implemented by the first terminal in the various methods of the embodiment of the present application. For the sake of brevity, they are not repeated here.

[0342] Optionally, the computer-readable storage medium can be applied to the second terminal in the embodiment of the present application, and the computer program enables the computer to execute the corresponding processes implemented by the second terminal in the various methods of the embodiment of the present application. For the sake of brevity, they are not repeated here.

[0343] An embodiment of the present application also provides a computer program product, including computer program instructions.

[0344] Optionally, the computer program product can be applied to the first terminal in the embodiment of the present application, and the computer program instructions enable the computer to execute the corresponding processes implemented by the first terminal in the various methods of the embodiment of the present application. For the sake of brevity, they are not repeated here.

[0345] Optionally, the computer program product can be applied to the second terminal in the embodiment of the present application, and the computer program instructions enable the computer to execute the corresponding processes implemented by the second terminal in the various methods of the embodiment of the present application. For the sake of brevity, they are not repeated here.

[0346] The embodiment of the present application also provides a computer program.

[0347] Optionally, the computer program can be applied to the first terminal in the embodiment of the present application. When the computer program runs on the computer, the computer executes the corresponding processes implemented by the first terminal in the various methods of the embodiment of the present application. For the sake of brevity, they are not repeated here.

[0348] Optionally, the computer program can be applied to the second terminal in the embodiment of the present application. When the computer program runs on the computer, the computer executes the corresponding processes implemented by the second terminal in the various methods of the embodiment of the present application. For the sake of brevity, they are not repeated here.

[0349] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0350] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0351] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0352] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0353] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0354] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0355] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A channel access method, applied to a first terminal, the method comprises: sending a first Physical SideLink Feedback Channel (PSFCH) to a second terminal, the first PSFCH being used to instruct the second terminal to access a channel through a specified type of channel access mode to use reserved resources of the second terminal.

2. The method according to claim 1, wherein, the first PSFCH is located in the time domain at: the last PSFCH transmission opportunity before the reserved resources; or, the last PSFCH transmission opportunity before a first moment; wherein the first moment is before the time slot where the reserved resources are located, and the time interval between the first moment and the start moment of the time slot where the reserved resources are located is: the sum of the maximum duration of the currently configured extended cyclic prefix and a first duration, and the first duration is defined by a standard, network configured, or pre-configured.

3. The method according to claim 1 or 2, wherein, the first PSFCH is located in the frequency domain at: the first interleaved resource block in an interleaved resource block set; or, at least one dedicated Physical Resource Block (PRB) in a first common interleaved resource block and a dedicated PRB set.

4. The method according to claim 1, wherein, the first PSFCH is located in the time domain at: a plurality of PSFCH transmission opportunities; among the plurality of PSFCH transmission opportunities, the time interval between two adjacent PSFCH transmission opportunities is a first time interval, and the last PSFCH transmission opportunity among the plurality of PSFCH transmission opportunities is: the last PSFCH transmission opportunity before the reserved resources; or, the last PSFCH transmission opportunity before a first moment; wherein the first moment is before the time slot where the reserved resources are located, and the time interval between the first moment and the start moment of the time slot where the reserved resources are located is: the sum of the maximum duration of the currently configured extended cyclic prefix and a first duration, and the first duration is defined by a standard, network configured, or pre-configured.

5. The method according to claim 4, wherein, the first time interval is network configured, pre-configured, or predefined.

6. The method according to claim 4 or 5, wherein, for any one of the plurality of PSFCH transmission opportunities, the first PSFCH on the PSFCH transmission opportunity is located in the frequency domain at: the first interleaved resource block in the interleaved resource block set corresponding to the PSFCH transmission opportunity; or, the first common interleaved resource block corresponding to the PSFCH transmission opportunity, and at least one dedicated PRB in the dedicated PRB set corresponding to the PSFCH transmission opportunity.

7. The method according to claim 3 or 6, wherein, the interleaved resource blocks in the interleaved resource block set do not overlap with the interleaved resource blocks for sending a second PSFCH; the dedicated PRB set does not overlap with the PRB set for sending the second PSFCH; the first common interleaved resource block is the same as the common interleaved resource block for sending the second PSFCH; Wherein, the second PSFCH includes: a PSFCH for feedback of Hybrid Automatic Repeat reQuest - Acknowledgement (HARQ - ACK), and a PSFCH for indicating resource conflict.

8. The method according to claim 3, 6 or 7, Wherein, the set of interleaved resource blocks is pre - configured or configured by a first signaling; the set of dedicated PRBs is pre - configured or configured by a second signaling.

9. The method according to claim 1, Wherein, the resources occupied by the first PSFCH are the same as those occupied by the PSFCH for indicating resource conflict, and the sequence cyclic shift of the first PSFCH is different from the sequence cyclic shift of the PSFCH for indicating resource conflict.

10. The method according to any one of claims 1 to 9, Wherein, sending the first PSFCH to the second terminal includes: when the first terminal meets a first condition, sending the first PSFCH to the second terminal.

11. The method according to any one of claims 1 to 10, Wherein, the resources occupied by the first PSFCH are associated with the reserved resources.

12. The method according to claim 1, Wherein, the resources occupied by the first PSFCH are associated with the Physical Sidelink Shared Channel (PSSCH) from the second terminal, and the reserved resources are used for re - transmission of the PSSCH.

13. The method according to claim 12, Wherein, sending the first PSFCH to the second terminal includes: when the first terminal fails to successfully decode the PSSCH and the first terminal meets a first condition, sending the first PSFCH to the second terminal; the first PSFCH is also used to indicate Negative Acknowledgement (NACK).

14. The method according to claim 10 or 13, Wherein, the first condition includes at least one of the following: The moment when the first terminal generates the Channel Occupancy Time (COT) is before the PSFCH transmission opportunity where the first PSFCH is located, and the duration of the COT includes the time slot where the reserved resources are located; The value of the channel access priority used by the first terminal to generate the COT is greater than or equal to a first value; The first terminal is the target receiving terminal for which the second terminal will send data on the reserved resources; The target identifier indicated in the Sidelink Control Information (SCI) for indicating the reserved resources is the identifier of the first terminal; There is a unicast connection between the first terminal and the second terminal; At the PSFCH transmission opportunity where the first PSFCH is located, the first terminal does not meet the condition for indicating resource conflict to the second terminal.

15. The method according to any one of claims 1 to 14, Wherein, When the second terminal accesses the channel through a specified type of channel access method to use the reserved resources of the second terminal, the reserved resources are used for the second terminal to send a sidelink channel, and the target identifier of the sidelink channel includes the identifier of the first terminal, and the identifier of the first terminal is the same as the target identifier indicated in the SCI for indicating the reserved resources. ​ 16. The method according to any one of claims 1 to 15, wherein, the specified type is type 2.

17. A channel access method applied to a second terminal, the method comprising: receiving a first physical side row feedback channel (PSFCH) from a first terminal, the first PSFCH being used to indicate that the second terminal accesses a channel through a specified type of channel access method to use reserved resources of the second terminal.

18. The method according to claim 17, wherein, the first PSFCH is located in the time domain at: the last PSFCH transmission opportunity before the reserved resources; or, the last PSFCH transmission opportunity before a first moment; wherein the first moment is before the time slot where the reserved resources are located, and the time interval between the first moment and the start moment of the time slot where the reserved resources are located is: the sum of the maximum duration of the currently configured extended cyclic prefix and a first duration, and the first duration is defined by a standard, network configured or pre-configured.

19. The method according to claim 17 or 18, wherein, the first PSFCH is located in the frequency domain at: the first interleaved resource block in an interleaved resource block set; or, at least one dedicated physical resource block (PRB) among a first common interleaved resource block and a dedicated PRB set.

20. The method according to claim 17, wherein, the first PSFCH is located in the time domain at: a plurality of PSFCH transmission opportunities; among the plurality of PSFCH transmission opportunities, the time interval between two adjacent PSFCH transmission opportunities is a first time interval, and the last PSFCH transmission opportunity among the plurality of PSFCH transmission opportunities is: the last PSFCH transmission opportunity before the reserved resources; or, the last PSFCH transmission opportunity before a first moment; wherein the first moment is before the time slot where the reserved resources are located, and the time interval between the first moment and the start moment of the time slot where the reserved resources are located is: the sum of the maximum duration of the currently configured extended cyclic prefix and a first duration, and the first duration is defined by a standard, network configured or pre-configured.

21. The method according to claim 20, wherein, the first time interval is network configured, pre-configured or predefined.

22. The method according to claim 20 or 21, wherein, for any one of the plurality of PSFCH transmission opportunities, the first PSFCH on the PSFCH transmission opportunity is located in the frequency domain at: the first interleaved resource block in the interleaved resource block set corresponding to the PSFCH transmission opportunity; or, the first common interleaved resource block corresponding to the PSFCH transmission opportunity, and at least one dedicated PRB in the dedicated PRB set corresponding to the PSFCH transmission opportunity.

23. The method according to claim 19 or 22, wherein, the interleaved resource blocks in the interleaved resource block set do not overlap with the interleaved resource blocks for sending a second PSFCH; the dedicated PRB set does not overlap with the PRB set for sending the second PSFCH; The first common interleaved resource block is the same as the common interleaved resource block for transmitting the second PSFCH; wherein, the second PSFCH includes: a PSFCH for feedback Hybrid Automatic Repeat reQuest - ACKnowledgment (HARQ - ACK), and a PSFCH for indicating resource conflict.

24. The method according to claim 19, 22 or 23, wherein, the set of interleaved resource blocks is pre - configured or configured by a first signaling; the set of dedicated PRBs is pre - configured or configured by a second signaling.

25. The method according to any one of claims 17 to 24, wherein, the method further includes: receiving first indication information for indicating that a resource conflict occurs on the reserved resources.

26. The method according to claim 25, wherein, when the time of receiving the first indication information is earlier than the time of receiving the first PSFCH, the method further includes: accessing a channel through a specified type of channel access method to use the reserved resources of the second terminal; when the time of receiving the first indication information is later than the time of receiving the first PSFCH, the method further includes: reselecting the reserved resources.

27. The method according to claim 25, wherein, the method further includes: reselecting the reserved resources.

28. The method according to claim 17, wherein, the resources occupied by the first PSFCH are the same as the resources occupied by the PSFCH for indicating resource conflict, and the sequence cyclic shift of the first PSFCH is different from the sequence cyclic shift of the PSFCH for indicating resource conflict.

29. The method according to any one of claims 17 to 28, wherein, the resources occupied by the first PSFCH are associated with the reserved resources.

30. The method according to claim 17, wherein, the resources occupied by the first PSFCH are associated with the Physical Sidelink Shared Channel (PSSCH) transmitted by the second terminal, and the reserved resources are used for retransmission of the PSSCH.

31. The method according to claim 30, wherein, the first PSFCH is further used to indicate Negative ACKnowledgment (NACK).

32. The method according to any one of claims 17 to 31, wherein, when the second terminal accesses a channel through a specified type of channel access method to use the reserved resources of the second terminal, the reserved resources are used for the second terminal to transmit a sidelink channel, and the target identifier of the sidelink channel includes the identifier of the first terminal, and the identifier of the first terminal is the same as the target identifier indicated in the Sidelink Control Information (SCI) for indicating the reserved resources.

33. The method according to any one of claims 17 to 32, wherein, the specified type is type 2.

34. A channel access method, applied to a first terminal, the method includes: Send inter-terminal coordination IUC information to a second terminal, where the ICU information is used to indicate multiple transmission resources of the second terminal, and the second terminal can access a channel through a specified type of channel access method to use some or all of the multiple transmission resources.

35. The method according to claim 34, wherein, the IUC information is carried in a second-order sidelink control information SCI; For any one of the multiple transmission resources, when the time interval between the time slot where the transmission resource is located and the time slot where the second-order SCI is located is less than a second time interval, the second terminal can access the channel through a specified type of channel access method to use the transmission resource.

36. The method according to claim 35, wherein, the second time interval is the maximum number of time slots included in the remaining time of the channel occupancy time COT generated by the first terminal, and the COT is shared with the second terminal.

37. The method according to any one of claims 34 to 36, wherein, the ICU information includes multiple time domain resource indication values TRIVs, each of the TRIVs is used to indicate the transmission resources of the second terminal on multiple time slots, the second terminal can access the channel through a specified type of channel access method to use a first transmission resource, and the transmission resources before the time slot where the first transmission resource is located; the first transmission resource is: the transmission resource on the last time slot indicated by the last TRIV among the multiple TRIVs; or, the transmission resource on the last time slot indicated by the first TRIV among the multiple TRIVs.

38. The method according to claim 37, wherein, the first transmission resource, and the transmission resources before the time slot where the first transmission resource is located, are included in the COT generated by the first terminal, and the COT is shared with the second terminal.

39. The method according to claim 34, wherein, the IUC information is carried in a media access control control element MAC CE; the MAC CE includes second indication information, and the second indication information is used to indicate that the second terminal can access the channel through a specified type of channel access method to use some or all of the multiple transmission resources.

40. The method according to any one of claims 34 to 39, wherein, the specified type is type 2.

41. A channel access method, applied to a second terminal, the method comprises: receiving inter-terminal coordination IUC information from a first terminal, where the ICU information is used to indicate multiple transmission resources of the second terminal, and the second terminal can access the channel through a specified type of channel access method to use some or all of the multiple transmission resources.

42. The method according to claim 41, wherein, the IUC information is carried in a second-order sidelink control information SCI; For any one of the multiple transmission resources, when the time interval between the time slot where the transmission resource is located and the time slot where the second-order SCI is located is less than a second time interval, the second terminal can access the channel through a specified type of channel access method to use the transmission resource.

43. The method according to claim 42, wherein, the second time interval is the maximum number of time slots included in the remaining time of the channel occupancy time (COT) generated by the first terminal, and the COT is shared with the second terminal.

44. The method according to any one of claims 41 to 43, wherein, the ICU information includes a plurality of time domain resource indication values (TRIVs), each TRIV is used to indicate the transmission resources of the second terminal on multiple time slots, the second terminal can access the channel through a specified type of channel access method to use the first transmission resource, and the transmission resources before the time slot where the first transmission resource is located; the first transmission resource is: the transmission resource on the last time slot indicated by the last TRIV among the plurality of TRIVs; or, the transmission resource on the last time slot indicated by the first TRIV among the plurality of TRIVs.

45. The method according to claim 44, wherein, the first transmission resource, and the transmission resources before the time slot where the first transmission resource is located, are included within the COT generated by the first terminal, and the COT is shared with the second terminal.

46. The method according to claim 41, wherein, the IUC information is carried in the media access control control element (MAC CE); the MAC CE includes second indication information, and the second indication information is used to indicate that the second terminal can access the channel through a specified type of channel access method to use some or all of the multiple transmission resources.

47. The method according to any one of claims 41 to 46, wherein, the specified type is type 2.

48. A channel access device, the device comprises: a first sending unit, configured to send a first physical side row feedback channel (PSFCH) to a second terminal, and the first PSFCH is used to indicate that the second terminal accesses the channel through a specified type of channel access method to use the reserved resources of the second terminal.

49. A channel access device, the device comprises: a first receiving unit, configured to receive a first physical side row feedback channel (PSFCH) from a first terminal, and the first PSFCH is used to indicate that the second terminal accesses the channel through a specified type of channel access method to use the reserved resources of the second terminal.

50. A channel access device, the device comprises: a second sending unit, configured to send inter-terminal coordination (IUC) information to a second terminal, and the ICU information is used to indicate multiple transmission resources of the second terminal, and the second terminal can access the channel through a specified type of channel access method to use some or all of the multiple transmission resources.

51. A channel access device, the device comprises: A second receiving unit, configured to receive inter-terminal coordination IUC information from a first terminal, where the ICU information is used to indicate a plurality of transmission resources of the second terminal, and the second terminal can access a channel through a specified type of channel access method to use some or all of the plurality of transmission resources.

52. A terminal, comprising: a processor and a memory, the memory being used to store a computer program, and the processor being used to call and run the computer program stored in the memory to execute the method according to any one of claims 1 to 16, or the method according to any one of claims 17 to 33, or the method according to any one of claims 34 to 40, or the method according to any one of claims 41 to 47.

53. A chip, comprising: a processor, configured to call and run a computer program from a memory, so that a device installed with the chip executes the method according to any one of claims 1 to 16, or the method according to any one of claims 17 to 33, or the method according to any one of claims 34 to 40, or the method according to any one of claims 41 to 47.

54. A computer-readable storage medium, used to store a computer program, where the computer program causes a computer to execute the method according to any one of claims 1 to 16, or the method according to any one of claims 17 to 33, or the method according to any one of claims 34 to 40, or the method according to any one of claims 41 to 47.

55. A computer program product, comprising computer program instructions, where the computer program instructions cause a computer to execute the method according to any one of claims 1 to 16, or the method according to any one of claims 17 to 33, or the method according to any one of claims 34 to 40, or the method according to any one of claims 41 to 47.

56. A computer program, where the computer program causes a computer to execute the method according to any one of claims 1 to 16, or the method according to any one of claims 17 to 33, or the method according to any one of claims 34 to 40, or the method according to any one of claims 41 to 47.

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