Transmitting feedback for data transmission through a sidelink
The disclosure relates to a communication technique and system for converging a 5G communication system for supporting a higher data transfer rate beyond a 4G system with an IoT technology. The disclosure relates to a method performed by a terminal for feeding back a hybrid automatic repeat request (HARQ) and to a terminal for performing the method, including: generating HARQ feedback information for data that is scheduled for the terminal in at least one slot; determining a transmission timing of the HARQ feedback information based on a minimum processing time for transmission of a physical sidelink feedback channel (PSFCH) of the terminal; and transmitting the HARQ feedback information based on the determined timing, wherein the minimum processing time for the PSFCH transmission is determined based on at least one of a subcarrier spacing, a configuration of a resource pool, and a time interval between a PSSCH and the PSFCH.
1. A method performed by a terminal for feeding back a hybrid automatic repeat request (HARQ) in a communication system, the method comprising:
generating HARQ feedback information for data that is scheduled for the terminal in at least one slot;
determining a transmission timing of the HARQ feedback information based on a minimum processing time for transmission of a physical sidelink feedback channel (PSFCH) of the terminal; and
transmitting the HARQ feedback information based on the determined timing,
wherein the minimum processing time for the PSFCH transmission is determined based on at least one of a subcarrier spacing, a configuration of a resource pool, or a time interval between a PSSCH and the PSFCH,
wherein a maximum number of bits of the HARQ feedback information is determined based on N and K, and
wherein N corresponds to a period in which a PSFCH resource is configured, and K corresponds to the minimum processing time for the PSFCH transmission.
2. The method of claim 1 , wherein the minimum processing time for the PSFCH transmission is determined based on whether the configuration for the resource pool is a configuration for unicast transmission or a configuration for groupcast transmission.
3. The method of claim 1 , wherein the minimum processing time for the PSFCH transmission is determined based on a last symbol of the PSSCH and a first symbol of the PSFCH.
4. The method of claim 1 , wherein the transmitting of the HARQ feedback information comprises:
in case that a plurality of PSFCHs are to be transmitted, determining a PSFCH to be transmitted among the plurality of PSFCHs, based on a sequence of PSSCHs corresponding to the plurality of PSFCHs or a quality of service (QoS) of the PSSCH.
5. The method of claim 1 , wherein the transmitting of the HARQ feedback information comprises,
in case that a plurality of PSFCHs are to be transmitted, determining transmission powers of the PSFCHs, and
adjusting the transmission powers of the PSFCHs according to a preconfigured ratio in case that a sum of the transmission powers of the PSFCHs exceeds a maximum available power of the terminal.
6. The method of claim 1 , wherein the transmitting of the HARQ feedback information comprises,
in case that a plurality of PSFCHs are to be transmitted, determining a PSFCH to be transmitted based on at least one of a number of HARQ feedback bits of each PSFCH or information on whether the PSFCH is feedback transmission for groupcast transmission.
7. The method of claim 1 , wherein the maximum number of bits of the HARQ feedback information is determined to be (N+K−1).
8. The method of claim 1 , wherein a minimum number of bits of the HARQ feedback information is determined to be a larger value between (N—K+1) and 0.
9. The method of claim 1 , wherein a PSFCH corresponding to unicast transmission is transmitted prior to a PSFCH corresponding to groupcast transmission, in case that a plurality of PSFCHs are transmitted for PSSCHs transmitted from different terminals.
10. The method of claim 1 , wherein a frequency band of the PSFCH is configured to be larger than a frequency band of the PSSCH.
11. A terminal for feeding back a hybrid automatic repeat request (HARQ) in a communication system, the terminal comprising:
a transceiver; and
a controller configured to:
generate HARQ feedback information for data that is scheduled for the terminal in at least one slot,
determine a transmission timing of the HARQ feedback information based on a minimum processing time for transmission of a physical sidelink feedback channel (PSFCH) of the terminal, and
transmit, via the transceiver, the HARQ feedback information based on the determined transmission timing,
wherein the minimum processing time for the PSFCH transmission is determined based on at least one of a subcarrier spacing, a configuration of a resource pool, or a time interval between a PSSCH and the PSFCH,
wherein a maximum number of bits of the HARQ feedback information is determined based on N and K, and
wherein N corresponds to a period in which a PSFCH resource is configured, and K corresponds to the minimum processing time for the PSFCH transmission.
12. The terminal of claim 11 , wherein the minimum processing time for the PSFCH transmission is determined based on whether the configuration for the resource pool is a configuration for unicast transmission or a configuration for groupcast transmission.
13. The terminal of claim 11 , wherein the minimum processing time for the PSFCH transmission is determined based on a last symbol of the PSSCH and a first symbol of the PSFCH.
14. The terminal of claim 11 , wherein the terminal is configured to, in case that a plurality of PSFCHs are to be transmitted, determine a PSFCH to be transmitted among the plurality of PSFCHs, based on a sequence of PSSCHs corresponding to the plurality of PSFCHs or a quality of service (QoS) of the PSSCH.
15. The terminal of claim 11 , wherein the terminal is configured to, in case that a plurality of PSFCHs are to be transmitted:
determine transmission powers of the PSFCHs; and
adjust the transmission powers of the PSFCHs according to a preconfigured ratio in case that a sum of the transmission powers of the PSFCHs exceeds a maximum available power of the terminal.
16. The terminal of claim 11 , wherein the terminal is configured to, in case that a plurality of PSFCHs are to be transmitted:
determine a PSFCH to be transmitted based on at least one of a number of HARQ feedback bits of each PSFCH or information on whether the PSFCH is feedback transmission for groupcast transmission.
17. The terminal of claim 11 , wherein the maximum number of bits of the HARQ feedback information is determined to be (N+K−1).
18. The terminal of claim 11 , wherein a minimum number of bits of the HARQ feedback information is determined to be a larger value between (N−K+1) and 0.
19. The terminal of claim 11 , wherein a PSFCH corresponding to unicast transmission is transmitted prior to a PSFCH corresponding to groupcast transmission, in case that a plurality of PSFCHs are transmitted for PSSCHs transmitted from different terminals.
20. The terminal according to claim 11 , wherein a frequency band of the PSFCH is configured to be larger than a frequency band of the PSSCH.