Method and apparatus for NR V2X sidelink HARQ procedure
Apparatuses and methods for obtaining and providing hybrid automatic repeat request acknowledgement (HARQ-ACK) information. A method for providing HARQ-ACK information includes receiving a configuration for a slot offset value and receiving a physical sidelink shared channel (PSSCH) over a number of sub-channels in a first slot. The PSSCH includes a transport block (TB). The method includes determining a second slot as an earliest slot with resources for transmission of a physical sidelink feedback channel (PSFCH) that is after the first slot by a number of slots equal to the slot offset value. The PSFCH includes the HARQ-ACK information that is in response to reception of the TB. The method further includes transmitting the PSFCH in the second slot.
1. A first user equipment (UE) in a wireless communication system, the first UE comprising:
a transceiver configured to:
receive, from a second UE, information indicating an identifier (ID) of the first UE; and
receive, from the second UE, a physical sidelink shared channel (PSSCH); and
a processor operably coupled to the transceiver, the processor configured to determine a physical sidelink feedback channel (PSFCH) resource based on a value modulo a number of PSFCH resources, wherein the value is based on the ID of the first UE,
wherein the transceiver is further configured to transmit, to the second UE, a PSFCH using the PSFCH resource.
2. The first UE of claim 1 , wherein:
the transceiver is further configured to receive information indicating a period of the PSFCH resource in a resource pool, and
the period of the PSFCH resource is a number of slots.
3. The first UE of claim 2 , wherein, when the number of slots is zero, a PSFCH transmission from the first UE in the resource pool is disabled.
4. The first UE of claim 1 , wherein the PSFCH resource includes a resource in a first slot after a last slot for a reception of the PSSCH.
5. The first UE of claim 1 , wherein:
the transceiver is further configured to receive, from the second UE, a sidelink control information (SCI) format,
the processor is further configured to identify a zone identifier (zone ID) included in the SCI format, and
the zone ID is related to position information of the second UE.
6. The first UE of claim 1 , wherein:
the transceiver is further configured to receive, from the second UE, a sidelink control information (SCI) format related to the PSSCH,
the SCI format includes information indicating whether the PSSCH is: (i) unicast, (ii) groupcast related to a hybrid automatic repeat request acknowledgement (HARQ-ACK) information reporting of a first option, or (ii) groupcast related to a HARQ-ACK information reporting of a second option,
the first option corresponds to a PSFCH transmission providing HARQ-ACK information with an ACK or NACK value, and
the second option corresponds to a PSFCH transmission providing HARQ-ACK information with a NACK value.
7. A second user equipment (UE) in a wireless communication system, the second UE comprising:
a transceiver configured to:
transmit, to a first UE, information indicating an identifier (ID) of the first UE;
transmit, to the first UE, a physical sidelink shared channel (PSSCH); and
receive, from the first UE, a physical sidelink feedback channel (PSFCH) using at least one PSFCH resource,
wherein the at least one PSFCH resource is determined based on a value modulo a number of PSFCH resources, wherein the value is based on the ID of the first UE.
8. The second UE of claim 7 , wherein:
the transceiver is further configured to transmit, to the first UE, configuration information indicating a period of the PSFCH resource in a resource pool, and
the period of the PSFCH resource is a number of slots.
9. The second UE of claim 8 , wherein, when the number of slots is zero, a PSFCH reception from the first UE in the resource pool is disabled.
10. The second UE of claim 7 , wherein the at least one PSFCH resource includes a resource in a first slot after a last slot for a reception of the PSSCH.
11. The second UE of claim 7 , wherein:
the transceiver is further configured to transmit, to the first UE, a sidelink control information (SCI) format, and
the SCI format includes a zone identifier (zone ID) which is related to position information of the second UE.
12. The second UE of claim 7 , wherein:
the transceiver is further configured to transmit, to the first UE, a sidelink control information (SCI) format related to the PSSCH,
the SCI format includes information indicating whether the PSSCH is (i) unicast, (ii) groupcast related to a hybrid automatic repeat request acknowledgement (HARQ-ACK) information reporting of a first option, or (iii) groupcast related to a HARQ-ACK information reporting of a second option,
the first option corresponds to a PSFCH transmission providing HARQ-ACK information with an ACK or NACK value, and
the second option corresponds to a PSFCH transmission providing HARQ-ACK information with a NACK value.
13. The second UE of claim 7 , further comprising:
a processor operably coupled to the transceiver, the processor configured to:
determine whether a total transmission power of the second UE exceeds a configured maximum transmission power of the second UE, wherein the total transmission power includes a power for an uplink transmission to a base station and a power for a sidelink transmission to the first UE;
when the sidelink transmission has a higher priority than the uplink transmission, reduce the uplink transmission power so that the total transmission power does not exceed the configured maximum transmission power; and
when the uplink transmission has a higher priority than the sidelink transmission, reduce the sidelink transmission power so that the total transmission power does not exceed the configured maximum transmission power,
wherein the transceiver is further configured to perform the uplink transmission and the sidelink transmission simultaneously based on the uplink transmission power and the sidelink transmission power.
14. A method for operating a first user equipment (UE) in a wireless communication system, the method comprising:
receiving, from a second UE, information indicating an identifier (ID) of the first UE;
receiving, from the second UE, a physical sidelink shared channel (PSSCH);
determining a physical sidelink feedback channel (PSFCH) resource based on a value modulo a number of PSFCH resources, wherein the value is based on the ID of the first UE; and
transmitting, to the second UE, a PSFCH using the PSFCH resource.
15. The method of claim 14 , further comprising:
receiving information indicating a period of the PSFCH resource in a resource pool, wherein the period of the PSFCH resource is a number of slots.
16. The method of claim 15 , wherein, when the number of slots is zero, a PSFCH transmission from the first UE in the resource pool is disabled.
17. The method of claim 14 , wherein the PSFCH resource includes a resource in a first slot after a last slot for a reception of the PSSCH.
18. The method of claim 14 , further comprising:
receiving, from the second UE, a sidelink control information (SCI) format; and
identifying a zone identifier (zone ID) included in the SCI format, wherein the zone ID is related to position information of the second UE.
19. The method of claim 14 , further comprising:
receiving, from the second UE, a sidelink control information (SCI) format related to the PSSCH, wherein:
the SCI format includes information indicating whether the PSSCH is: (i) unicast, (ii) groupcast related to a hybrid automatic repeat request acknowledgement (HARQ-ACK) information reporting of a first option, or (iii) groupcast related to a HARQ-ACK information reporting of a second option,
the first option corresponds to a PSFCH transmission providing HARQ-ACK information with an ACK or NACK value, and
the second option corresponds to a PSFCH transmission providing HARQ-ACK information with a NACK value.