Multi-transmitter scheduling using slot-based and sub-slot based physical sidelink shared channels

1. A method of wireless communication performed by a user equipment (UE), the method comprising:

receiving a sub-slot resource pool (RP) configuration indicating a plurality of subchannels in an unlicensed subband;

performing a clear channel assessment (CCA);

transmitting, to a first UE based on the CCA being successful, a first transport block (TB) in at least one subchannel of the plurality of subchannels via a first sub-PSSCH associated with a first sub-slot; and

transmitting, to at least one of the first UE or a second UE, a second TB via a PSSCH associated with a slot.

2. The method of claim 1 , wherein:

the first sub-slot borders a slot boundary; and

the slot borders the slot boundary.

3. The method of claim 1 , wherein:

the transmitting the second TB comprises:

transmitting, to the at least one of the first UE or the second UE, the second TB via the PSSCH associated with the slot without performing another CCA.

4. The method of claim 1 further comprising:

mapping all of a sub-PSCCH, a sub-PSSCH, an automatic gain control (AGC) symbol, and sidelink control information (SCI) to each sub-slot of a plurality of sub-slots, wherein the plurality of sub-slots includes the first sub-slot; and

wherein the transmitting the first TB via the first sub-PSSCH is based at least in part on the mapping.

5. The method of claim 4 , further comprising:

omitting a gap symbol in a last symbol of a last sub-slot of the plurality of sub-slots; and

mapping the sub-PSSCH to the last symbol of the last sub-slot of the plurality of sub-slots.

6. The method of claim 4 , further comprising:

mapping an automatic gain control (AGC) symbol to a leading symbol of a leading sub-slot of the plurality of sub-slots.

7. The method of claim 1 , further comprising:

receiving, from a base station (BS), a configured grant (CG) associated with a resource allocation for a plurality of sub-slots;

mapping, based on the CG, both a sub-PSSCH and second-stage sidelink control information (SCI-2) to each sub-slot of the plurality of sub-slots, wherein the plurality of sub-slots includes the first sub-slot; and

mapping, based on the CG, an automatic gain control (AGC) symbol to a leading symbol of a leading sub-slot of the plurality of sub-slots.

8. The method of claim 1 , further comprising:

transmitting, in at least one sub-slot of a plurality of sub-slots, a padding, wherein the plurality of sub-slots includes the first sub-slot.

9. A method of wireless communication performed by a user equipment (UE), the method comprising:

receiving, from a base station (BS), a configuration indicating at least one subchannel within at least one subband;

receiving, from another UE, a first transport block (TB) via a sub-PSSCH associated with a sub-slot;

receiving, from the other UE, a second TB via a PSSCH associated with a slot; and

performing blind decoding on a second-stage sidelink control information (SCI-2) in a subchannel within the at least one subband.

10. The method of claim 9 , further comprising:

detecting a boundary between the sub-slot and the slot; and

wherein the receiving the second TB via the PSSCH associated with the slot comprises:

receiving, from the other UE, the second TB based on detecting the boundary between the sub-slot and the slot.

11. The method of claim 9 , further comprising:

receiving, from the other UE, an instruction in the sub-PSSCH that instructs the UE to receive the second TB via the PSSCH associated with the slot; and

wherein the receiving the second TB via the PSSCH associated with the slot comprises:

receiving, from the other UE, the second TB based on the instruction.

12. The method of claim 9 ,

wherein the configuration further indicates at least one of:

resources associated with the sub-slot;

a starting subchannel index associated with the sub-slot;

a number of subchannels associated with the sub-slot;

a modulation and coding scheme associated with the sub-slot;

a beta offset associated with the sub-slot; or

a search space period associated with the sub-slot.

13. The method of claim 12 , wherein the receiving the configuration comprises:

receiving, from the BS, the configuration in a radio resource control (RRC) message.

14. The method of claim 12 , wherein the receiving the configuration comprises:

receiving, from the BS, the configuration indicating the search space period associated with the sub-slot; and

further comprising:

performing blind decoding on a second-stage sidelink control information (SCI-2) in one sub-slot within the search space period.

15. The method of claim 12 , wherein the configuration further indicates a group identifier assigned to the UE; and

further comprising:

performing blind decoding on a second-stage sidelink control information (SCI-2) in each subchannel associated with the group identifier.

16. The method of claim 9 , further comprising:

monitoring for a demodulation reference signal (DMRS); and

wherein the performing blind decoding on the SCI-2 is based on detecting the DMRS.

17. A user equipment (UE) comprising a transceiver, a memory, and a processor coupled to the transceiver and the memory, the UE configured to:

receive a sub-slot resource pool (RP) configuration indicating a plurality of subchannels in an unlicensed subband;

perform a clear channel assessment (CCA);

transmit, to a first UE based on the CCA being successful, a first transport block (TB) in at least one subchannel of the plurality of subchannels via a first sub-PSSCH associated with a first sub-slot; and

transmit, to at least one of the first UE or a second UE, a second TB via a PSSCH associated with a slot.

18. The UE of claim 17 , wherein:

the first sub-slot borders a slot boundary; and

the slot borders the slot boundary.

19. The UE of claim 17 , wherein the UE is further configured to:

transmit, to the at least one of the first UE or the second UE, the second TB via the PSSCH associated with the slot without performing another CCA.

20. The UE of claim 17 , wherein the UE is further configured to:

map all of a sub-PSCCH, a sub-PSSCH, an automatic gain control (AGC) symbol, and sidelink control information (SCI) to each sub-slot of a plurality of sub-slots, wherein the plurality of sub-slots includes the first sub-slot; and

transmit the first TB via the first sub-PSSCH based at least in part on the mapping.

21. The UE of claim 20 , wherein the UE is further configured to:

omit a gap symbol in a last symbol of a last sub-slot of the plurality of sub-slots; and

map the sub-PSSCH to the last symbol of the last sub-slot of the plurality of sub-slots.

22. The UE of claim 20 , wherein the UE is further configured to:

map an automatic gain control (AGC) symbol to a leading symbol of a leading sub-slot of the plurality of sub-slots.

23. The UE of claim 17 , wherein the UE is further configured to:

receive, from a base station (BS), a configured grant (CG) associated with a resource allocation for a plurality of sub-slots;

map, based on the CG, both a sub-PSSCH and second-stage sidelink control information (SCI-2) to each sub-slot of the plurality of sub-slots, wherein the plurality of sub-slots includes the first sub-slot; and

map, based on the CG, an automatic gain control (AGC) symbol to a leading symbol of a leading sub-slot of the plurality of sub-slots.

24. The UE of claim 17 , wherein the UE is further configured to:

transmit, in at least one sub-slot of a plurality of sub-slots, a padding, wherein the plurality of sub-slots includes the first sub-slot.

25. A user equipment (UE) comprising a transceiver, a memory, and at least one processor coupled to the transceiver and the memory, wherein the memory stores instructions that are executable by the at least one processor, individually or in any combination, to cause the UE to:

receive, from a base station (BS), a configuration indicating at least one subchannel within at least one subband;

receive, from another UE, a first transport block (TB) via a sub-PSSCH associated with a sub-slot;

receive, from the other UE, a second TB via a PSSCH associated with a slot; and

perform blind decoding on a second-stage sidelink control information (SCI-2) in a subchannel within the at least one subband.

26. The UE of claim 25 , wherein the UE is further configured to:

detect a boundary between the sub-slot and the slot;

receive, from the other UE, the second TB based on detecting the boundary between the sub-slot and the slot;

receive, from the other UE, an instruction in the sub-PSSCH that instructs the UE to receive the second TB via the PSSCH associated with the slot; and

receive, from the other UE, the second TB based on the instruction.

27. The UE of claim 25 ,

wherein the configuration further indicates at least one of:

resources associated with the sub-slot;

a starting subchannel index associated with the sub-slot;

a number of subchannels associated with the sub-slot;

a modulation and coding scheme associated with the sub-slot;

a beta offset associated with the sub-slot; or

a search space period associated with the sub-slot.