Method and device for performing SL transmission in NR V2X

1. A method for performing wireless communication by a first device, the method comprising:

mapping, by the first device, a first sidelink control information (SCI) to a resource related to a physical sidelink control channel (PSCCH);

mapping, by the first device, based on a remainder obtained by dividing a part of cyclic redundancy check (CRC) on the PSCCH by frequency density (K PT-RS ) related to phase tracking-reference signal (PT-RS) mapping, a PT-RS to a resource related to a physical sidelink shared channel (PSSCH);

mapping, by the first device, a second SCI to a resource not used for transmission of the PT-RS among the resource related to the PSSCH; and

transmitting, by the first device, the first SCI, the second SCI, and the PT-RS to a second device.

2. The method of claim 1 ,

wherein the PT-RS is mapped to the resource related to the PSSCH, based on the remainder and a resource element (RE) offset related to the PT-RS.

3. The method of claim 2 , wherein the PT-RS is mapped to a first RB after the remainder from an RB with a smallest index among RBs related to the PSSCH.

4. The method of claim 3 , wherein the PT-RS is mapped to a first subcarrier after the RE offset from a subcarrier with a smallest index among subcarriers in the first RB.

5. The method of claim 1 , wherein the PT-RS is not mapped to the resource related to the PSCCH.

6. The method of claim 5 , wherein, by puncturing the PT-RS, the PT-RS is not mapped to the resource related to the PSCCH.

7. The method of claim 1 , wherein the second SCI is mapped in an ascending order of a time axis index after mapping in an ascending order of a frequency axis index.

8. The method of claim 1 , further comprising:

mapping, by the first device, a channel state information-reference signal (CSI-RS) to the resource related to the PSSCH; and

transmitting, by the first device, the CSI-RS to the second device,

wherein the CSI-RS is not mapped to a symbol to which the second SCI is mapped.

9. The method of claim 1 , further comprising:

mapping, by the first device, a demodulation-reference signal (DM-RS) to the resource related to the PSSCH; and

transmitting, by the first device, the DM-RS to the second device,

wherein the second SCI is not mapped to the resource to which the DM-RS is mapped.

10. The method of claim 1 , wherein a number of antenna ports related to the PT-RS is a same as a number of antenna ports related to a DM-RS.

11. The method of claim 10 , wherein an association between an antenna port related to the PT-RS and an antenna port related to the DM-RS is fixed.

12. The method of claim 1 , wherein the first SCI includes information regarding a number of antenna ports related to a DM-RS, and

wherein the PT-RS is mapped to the resource related to the PSSCH based on the number of antenna ports related to the DM-RS.

13. A first device adapted to perform wireless communication, the first device comprising:

at least one transceiver;

at least one processor; and

at least one memory connected to the at least one processor and storing instructions that, based on being executed, cause the at least one processor to perform operations comprising:

mapping a first sidelink control information (SCI) to a resource related to a physical sidelink control channel (PSCCH);

mapping, based on a remainder obtained by dividing a part of cyclic redundancy check (CRC) on the PSCCH by frequency density (K PT-RS ) related to phase tracking-reference signal (PT-RS) mapping, a PT-RS to a resource related to a physical sidelink shared channel (PSSCH);

mapping a second SCI to a resource not used for transmission of the PT-RS among the resource related to the PSSCH; and

transmitting the first SCI, the second SCI, and the PT-RS to a second device.

14. The first device of claim 13 ,

wherein the PT-RS is mapped to the resource related to the PSSCH, based on the remainder and a resource element (RE) offset related to the PT-RS.

15. The first device of claim 14 , wherein the PT-RS is mapped to a first RB after the remainder from an RB with a smallest index among RBs related to the PSSCH.

16. The first device of claim 15 , wherein the PT-RS is mapped to a first subcarrier after the RE offset from a subcarrier with a smallest index among subcarriers in the first RB.

17. The first device of claim 13 , wherein the PT-RS is not mapped to the resource related to the PSCCH.

18. The first device of claim 17 , wherein, by puncturing the PT-RS, the PT-RS is not mapped to the resource related to the PSCCH.

19. A processing device adapted to control a first device performing wireless communication, the processing device comprising:

at least one processor; and

at least one memory connected to the at least one processor and storing instructions that, based on being executed, cause the at least one processor to perform operations comprising:

mapping a first sidelink control information (SCI) to a resource related to a physical sidelink control channel (PSCCH);

mapping, based on a remainder obtained by dividing a part of cyclic redundancy check (CRC) on the PSCCH by frequency density (K PT-RS ) related to phase tracking-reference signal (PT-RS) mapping, a PT-RS to a resource related to a physical sidelink shared channel (PSSCH);

mapping a second SCI to a resource not used for transmission of the PT-RS among the resource related to the PSSCH; and

transmitting the first SCI, the second SCI, and the PT-RS to a second device.