SLSS transmission method in unlicensed frequency band

Abstract

One disclosure of the present specification provides a method by which a UE performs communication. The method comprises the steps of: receiving a first SLSS from a reference UE on the basis of an S-SSB period through a first channel; measuring an RSRP for a first SLSS during an evaluation time T, where the first channel belongs to an unlicensed band, the evaluation time T based on L, the reference UE performing a first CCA on the first channel for transmission of the first SLSS, and the reference UE failing to transmit the first SLSS due to a failure of the first CCA during the L S-SSB periods; and determining whether the UE sends the second SLSS based on the RSRP measurement result.

Claims

1. A method for performing communication performed by a user equipment (UE), the method comprising the following steps: receiving a first sidelink synchronization signal SLSS from a reference UE based on a sidelink synchronization signal block S-SSB period via a first channel; performing measurement of a reference signal received power RSRP for the first SLSS during an evaluation time T; The first channel belongs to an unlicensed frequency band. Wherein, the evaluation time T is based on the quantity L, The reference UE performs a first clear channel assessment CCA on the first channel used to send the first SLSS, The reference UE fails to send the first SLSS during the number L of S-SSB periods due to a failure of the first CCA, Whether to transmit a second SLSS is determined based on a result of the measurement.

2. The method according to claim 1, in, The step of receiving the first SLSS is based on the reference UE successfully performing the first CCA.

3. The method according to claim 1, in, Based on the UE not being configured for sidelink discontinuous reception (SL-DRX), the evaluation time T is a value obtained by multiplying the S-SSB period by a value obtained by adding 4 to the number L, wherein, based on the SL-DRX cycle set to the UE being less than or equal to 160 ms, the evaluation time T is a value obtained by multiplying the S-SSB period by a value obtained by adding 4 to the number L, Here, based on the SL-DRX cycle set to the UE being greater than 160 ms, the evaluation time T is a value obtained by multiplying the SL-DRX cycle by a value obtained by adding 4 to the number L.

4. The method according to claim 1, further comprising the steps of: performing a second CCA on a second channel for the second SLSS based on the determination to transmit the second SLSS; Based on the success of the second CCA, sending the second SLSS via the second channel, The second channel belongs to an unlicensed frequency band. Wherein, based on the failure of the second CCA, the UE skips sending the second SLSS.

5. The method according to claim 4, further comprising the steps of: selecting a third channel based on the UE failing to send the second SLSS via the second channel within a maximum time; as well as A third SLSS is transmitted via the third channel.

6. The method according to claim 4, further comprising the steps of: Re-measurement of the RSRP of the first SLSS is performed during the evaluation time T based on the UE failing to transmit the second SLSS via the second channel within a maximum time.

7. The method according to claim 1, in, The reference UE performs the first CCA multiple times at a specific interval for sending the first SLSS, The step of receiving the first SLSS is based on the reference UE successfully performing the first CCA.

8. A user equipment (UE) for performing communication, the UE comprising: transceiver; as well as processor, The processor performs an operation, the operation including: receiving a first sidelink synchronization signal SLSS from a reference UE based on a sidelink synchronization signal block S-SSB period via a first channel; performing measurement of a reference signal received power RSRP for the first SLSS during an evaluation time T; The first channel belongs to an unlicensed frequency band. Wherein, the evaluation time T is based on the quantity L, The reference UE performs a first clear channel assessment CCA on the first channel used to send the first SLSS, The reference UE fails to send the first SLSS during the number L of S-SSB periods due to a failure of the first CCA, Whether to transmit a second SLSS is determined based on a result of the measurement.

9. The UE according to claim 8, in, The step of receiving the first SLSS is based on the reference UE successfully performing the first CCA.

10. The UE according to claim 8, in, Based on the UE not being configured for sidelink discontinuous reception (SL-DRX), the evaluation time T is a value obtained by multiplying the S-SSB period by a value obtained by adding 4 to the number L, wherein, based on the SL-DRX cycle set to the UE being less than or equal to 160 ms, the evaluation time T is a value obtained by multiplying the S-SSB period by a value obtained by adding 4 to the number L, Here, based on the SL-DRX cycle set to the UE being greater than 160 ms, the evaluation time T is a value obtained by multiplying the SL-DRX cycle by a value obtained by adding 4 to the number L.

11. The UE according to claim 8, wherein: The operations further include: performing a second CCA on a second channel for the second SLSS based on the determination to transmit the second SLSS; Based on the success of the second CCA, sending the second SLSS via the second channel, The second channel belongs to an unlicensed frequency band. Wherein, based on the failure of the second CCA, the UE skips sending the second SLSS.

12. The UE according to claim 11, wherein: The operations further include: selecting a third channel based on the UE failing to transmit the second SLSS via the second channel within a maximum time; and A third SLSS is transmitted via the third channel.

13. The UE according to claim 11, wherein: The operations further include: Re-measurement of the RSRP of the first SLSS is performed during the evaluation time T based on the UE failing to transmit the second SLSS via the second channel within a maximum time.

14. The UE according to claim 8, in, The reference UE performs the first CCA multiple times at a specific interval for sending the first SLSS, The step of receiving the first SLSS is based on the reference UE successfully performing the first CCA.

15. A mobile communication device, comprising: at least one processor; as well as at least one memory storing instructions and being operatively connected to the at least one processor, The at least one processor operates based on the instruction, and the instruction performs an operation, the operation including: receiving a first sidelink synchronization signal SLSS from a reference UE based on a sidelink synchronization signal block S-SSB period via a first channel; performing measurement of a reference signal received power RSRP for the first SLSS during an evaluation time T; The first channel belongs to an unlicensed frequency band. Wherein, the evaluation time T is based on the quantity L, The reference UE performs a first clear channel assessment CCA on the first channel used to send the first SLSS, The reference UE fails to send the first SLSS during the number L of S-SSB periods due to a failure of the first CCA, Whether to transmit a second SLSS is determined based on a result of the measurement.

16. A non-volatile computer-readable storage medium having recorded thereon instructions, in, Upon execution by one or more processors, the instructions cause the one or more processors to perform operations comprising: receiving a first sidelink synchronization signal SLSS from a reference UE based on a sidelink synchronization signal block S-SSB period via a first channel; performing measurement of a reference signal received power RSRP for the first SLSS during an evaluation time T; The first channel belongs to an unlicensed frequency band. Wherein, the evaluation time T is based on the quantity L, The reference UE performs a first clear channel assessment CCA on the first channel used to send the first SLSS, The reference UE fails to send the first SLSS during the number L of S-SSB periods due to a failure of the first CCA, Whether to transmit a second SLSS is determined based on a result of the measurement.

Images