Method and apparatus for transmitting HARQ-ACK feedback for sidelink communication
The present disclosure is related to methods and apparatuses. According to some embodiments of the disclosure, a method performed by a first UE for wireless communication includes: receiving, from a second UE, sidelink control information (SCI) on a first interlace on a carrier, wherein the SCI schedules data transmission on the carrier, and the first interlace comprises evenly-spaced resource blocks (RBs) in frequency domain; and transmitting, from the first UE, corresponding to the data transmission, a hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback on a first feedback resource based on the SCI.
1. A method performed by a first user equipment (UE) for wireless communication, the method comprising:
receiving, from a second UE, sidelink control information (SCI) on a first interlace on a carrier, wherein the SCI schedules data transmission on one or more interlaces on the carrier and the first interlace comprises evenly-spaced resource blocks (RBs) in a frequency domain; and
transmitting, corresponding to the data transmission, a hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback on a feedback resource, wherein the feedback resource is one of multiple feedback resources indicated by the SCI based on the one or more interlaces on the carrier, and wherein a number of the multiple feedback resources is determined based on a number of interlaces dependent on subcarrier spacing of the carrier and a number of cyclic shifts.
2. The method of claim 1 , wherein the SCI indicates an index of the feedback resource in the multiple feedback resources.
3. The method of claim 1 , further comprising determining an index of the feedback resource in the multiple feedback resources based on one or more of:
the number of interlaces defined based on the subcarrier spacing of the carrier;
a slot index of a slot for the data transmission within a slot set, the slot set including slots with corresponding physical sidelink feedback channel (PSFCH) transmissions in a same slot; or
an interlace index that is based on one or more of an index of the first interlace, or an index of an interlace for the data transmission.
4. The method of claim 1 , further comprising:
receiving a radio resource control (RRC) signaling that indicates a plurality of feedback resource sets for accommodating feedback from a plurality of UE groups.
5. The method of claim 4 , wherein the SCI indicates an index of a first feedback resource set of the plurality of feedback resource sets.
6. The method of claim 1 , wherein the first UE and the second UE are from a UE group, and the method further comprises:
determining an index of the feedback resource of the multiple feedback resources based on one or more of:
a number of slots within a slot set, the slot set including slots with corresponding physical sidelink feedback channel (PSFCH) transmissions in a same slot;
an identifier (ID) of the first UE in the UE group;
an ID of the second UE in the UE group; or
the number of interlaces dependent on the subcarrier spacing of the carrier.
7. The method of claim 1 , wherein the SCI indicates at least one of:
an index of a second interlace, and the feedback resource is transmitted on the second interlace;
the index of the second interlace and an index of a subband of the carrier, and the feedback resource is transmitted on a partial interlace of the second interlace corresponding to the index of the subband of the carrier;
an index of the partial interlace, and the feedback resource is transmitted on the partial interlace;
an index of the subband of the carrier, and the feedback resource is transmitted on the partial interlace of the first interlace corresponding to the index of the subband of the carrier; or
the index of the subband of the carrier, and the feedback resource is transmitted on the partial interlace of an interlace for the data transmission corresponding to the index of the subband of the carrier.
8. A first user equipment (UE) for wireless communication, comprising:
at least one memory; and
at least one processor coupled with the at least one memory and configured to cause the first UE to:
receive, from a second UE, sidelink control information (SCI) on a first interlace on a carrier, wherein the SCI schedules data transmission on one or more interlaces on the carrier and the first interlace comprises evenly-spaced resource blocks (RBs) in frequency domain; and
transmit, corresponding to the data transmission, a hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback on a feedback resource, wherein the feedback resource is one of multiple feedback resources indicated by the SCI based on the one or more interlaces on the carrier, and wherein a number of the multiple feedback resources is determined based on a number of interlaces dependent on subcarrier spacing of the carrier and a number of cyclic shifts.
9. The first UE of claim 8 , wherein the SCI indicates an index of the feedback resource in the multiple feedback resources.
10. The first UE of claim 8 , wherein the at least one processor is configured to cause the first UE to determine an index of the feedback resource in the multiple feedback resources based on one or more of:
the number of interlaces dependent on the subcarrier spacing of the carrier;
a slot index of a slot for the data transmission within a slot set, the slot set including slots with corresponding physical sidelink feedback channel (PSFCH) transmissions in a same slot; or
an interlace index that is based on one or more of an index of the first interlace, or an index of an interlace for the data transmission.
11. The first UE of claim 8 , wherein the at least one processor is configured to cause the first UE to receive a radio resource control (RRC) signaling that indicates a plurality of feedback resource sets for accommodating feedback from a plurality of UE groups.
12. The first UE of claim 11 , wherein the SCI indicates an index of a first feedback resource set of the plurality of feedback resource sets.
13. The first UE of claim 8 , wherein the first UE and the second UE are from a UE group, and wherein the at least one processor is configured to cause the first UE to:
determining an index of the feedback resource of multiple feedback resources based on one or more of:
a number of slots within a slot set, the slot set including slots with corresponding physical sidelink feedback channel (PSFCH) transmissions in a same slot;
an identifier (ID) of the first UE in the UE group;
an ID of the second UE in the UE group; or
the number of interlaces dependent on the subcarrier spacing of the carrier.
14. The first UE of claim 8 , wherein the SCI indicates at least one of:
an index of a second interlace, and the feedback resource is transmitted on the second interlace;
the index of the second interlace and an index of a subband of the carrier, and the feedback resource is transmitted on a partial interlace of the second interlace corresponding to the index of the subband of the carrier;
an index of the partial interlace, and the feedback resource is transmitted on the partial interlace;
an index of the subband of the carrier, and the feedback resource is transmitted on the partial interlace of the first interlace corresponding to the index of the subband of the carrier; or
the index of the subband of the carrier, and the feedback resource is transmitted on the partial interlace of an interlace for the data transmission corresponding to the index of the subband of the carrier.
15. A first user equipment (UE) for wireless communication, comprising:
at least one memory; and
at least one processor coupled with the at least one memory and configured to cause the first UE to:
transmit, to a second UE, sidelink control information (SCI) on a first interlace on a carrier, wherein the SCI schedules data transmission on one or more interlaces on the carrier and the first interlace comprises evenly-spaced resource blocks (RBs) in a frequency domain; and
receive, corresponding to the data transmission, a hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback on a feedback resource, wherein the feedback resource is one of multiple feedback resources indicated by the SCI based on the one or more interlaces on the carrier, and wherein a number of the multiple feedback resources is determined based on a number of interlaces dependent on subcarrier spacing of the carrier and a number of cyclic shifts.
16. The first UE of claim 15 , wherein an index of the feedback resource is based on at least one or more of:
the number of interlaces dependent on the subcarrier spacing of the carrier;
a slot index of a slot for the data transmission within a slot set, the slot set including slots with corresponding physical sidelink feedback channel (PSFCH) transmissions in a same slot; or
an interlace index that is based on one or more of the index of the first interlace, or an index of an interlace for the data transmission.
17. The first UE of claim 15 , wherein the first UE and an additional UE are from a UE group, and the at least one processor is configured to cause the first UE to determine an index of the feedback resource based on at least one or more of:
a number of slots within a slot set that includes slots with corresponding physical sidelink feedback channel (PSFCH) transmissions in a same slot;
an identifier (ID) of the first UE in the UE group;
an ID of the additional UE in the UE group; or
the number of interlaces dependent on the subcarrier spacing of the carrier.
18. The first UE of claim 15 , wherein the HARQ-ACK feedback is received in one or more symbols within a slot, and the at least one processor is configured to cause the first UE to decode the HARQ-ACK feedback using at least one of a cyclic shift or an orthogonal cover code (OCC), wherein at least one of an index of the cyclic shift, or an index of the OCC indicated in the SCI; or
at least one of the index of the cyclic shift and the index of the OCC is determined based on one or more of: an index of the slot within a radio frame, an index of the one or more symbols within the slot, or an index of the one or more symbols with respect to the first symbol of the one or more symbols in a time domain.
19. A processor for wireless communication, comprising:
at least one controller coupled with at least one memory and configured to cause the processor to:
receive, from a user equipment (UE), sidelink control information (SCI) on a first interlace on a carrier, wherein the SCI schedules data transmission on one or more interlaces on the carrier and the first interlace comprises evenly-spaced resource blocks (RBs) in frequency domain; and
transmit, corresponding to the data transmission, a hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback on a feedback resource, wherein the feedback resource is one of multiple feedback resources indicated by the SCI based on the one or more interlaces on the carrier, and wherein a number of the multiple feedback resources is determined based on a number of interlaces dependent on subcarrier spacing of the carrier and a number of cyclic shifts.
20. The processor of claim 19 , wherein the SCI indicates an index of the feedback resource in the multiple feedback resources.