Conditional configured grant (CG) occasions for uplink transmission

1. A method for wireless communications by a user equipment (UE), comprising:

receiving, from a network entity, a configuration for conditional configured grant (CG) occasions for uplink transmission, each conditional CG occasion having multiple conditional CG resources;

monitoring, within sensing windows configured for the conditional CG resources, for signals from one or more other UEs to determine availability of one or more of the conditional CG resources of a conditional CG occasion, wherein the one or more of the conditional CG resources are not available when a predefined sequence of the signals is detected within the sensing windows;

deciding to perform uplink transmission on the one or more of the conditional CG resources when the one or more of the conditional CG resources are available;

performing a pseudo random selection to identify a subset of the conditional CG resources that are available based on the monitoring; and

randomly selecting one conditional CG resource from the subset of the conditional CG resources to perform the uplink transmission.

2. The method of claim 1 , wherein:

the UE determines that a conditional CG resource is unavailable if the UE detects, within a corresponding sensing window, a reservation message, sent by another UE, reserving resources in the conditional CG resource of a future conditional CG occasion.

3. The method of claim 1 , wherein the multiple conditional CG resources share a same sensing window.

4. The method of claim 1 , wherein the predefined sequence is a demodulation reference signal (DMRS) sequence.

5. The method of claim 1 , wherein the UE determines that a conditional CG resource is unavailable when the UE detects within the corresponding sensing window that an energy of the predefined sequence is more than a threshold value.

6. The method of claim 1 , wherein the configuration indicates a periodicity and a timing varying offset.

7. The method of claim 6 , further comprising:

determining a location, in time, of the conditional CG resources for a given conditional CG occasion based, at least in part, on the time varying offset.

8. The method of claim 2 , wherein the reservation message indicates at least one of: a time domain resource allocation (TDRA), a frequency domain resource allocation (FDRA), or a priority indicated in a sidelink control information (SCI).

9. The method of claim 8 , wherein the FDRA indicated in the reservation message is different from a FDRA used for transmitting the reservation message.

10. The method of claim 2 , further comprising:

after detecting the reservation message, validating a reservation of the conditional CG resource with a sequence-based detection.

11. The method of claim 1 , further comprising:

determining indices corresponding to the subset of the conditional CG resources by running hashing functions corresponding to the subset of the conditional CG resources in parallel.

12. The method of claim 1 , further comprising:

receiving, from the network entity, a retransmission command, wherein a size of the subset of the conditional CG resources that are available for the retransmission is dynamically increased based on the retransmission command.

13. The method of claim 1 , further comprising:

receiving, from the network entity, a retransmission command, wherein a probability of the UE determining the subset of the conditional CG resources that are available for the retransmission is increased based on the retransmission command.

14. A method for wireless communications by a network entity, comprising:

generating a configuration for conditional configured grant (CG) occasions for uplink transmission, each conditional CG occasion having multiple conditional CG resources;

sending, to a user equipment (UE), the configuration to:

monitor within sensing windows configured for the conditional CG resources, for signals from one or more other UEs to determine availability of one or more of the conditional CG resources of a conditional CG occasion, wherein the one or more of the conditional CG resources are not available when a predefined sequence of the signals is detected within the sensing windows; and

decide to perform uplink transmission on the one or more of the conditional CG resources when the one or more of the conditional CG resources are available; and

sending, to the UE, a retransmission command, wherein a size of the conditional CG resources that are available for the retransmission is dynamically increased based on the retransmission command.

15. The method of claim 14 , wherein:

the UE determines that a conditional CG resource is unavailable if the UE detects, within a corresponding sensing window a reservation message, sent by another UE, reserving resources in the conditional CG resource of a future conditional CG occasion.

16. The method of claim 14 , wherein the multiple conditional CG resources share a same sensing window.

17. The method of claim 14 , wherein the predefined sequence is a demodulation reference signal (DMRS) sequence.

18. The method of claim 15 , wherein the reservation message indicates at least one of: a time domain resource allocation (TDRA), a frequency domain resource allocation (FDRA), or a priority indicated in a sidelink control information (SCI).

19. The method of claim 18 , wherein the FDRA indicated in the reservation message is different from a FDRA used for transmitting the reservation message.

20. The method of claim 14 ,

wherein a probability of the UE determining the conditional CG resources that are available for the retransmission is increased based on the retransmission command.

21. The method of claim 15 , wherein the UE is configured to send reservation messages at a predefined reservation message window.

22. The method of claim 15 , wherein the UE is configured to send reservation messages at a predefined reservation message window only for traffic of a certain priority.

23. An apparatus for wireless communications by a user equipment (UE), comprising:

a memory; and

a processor coupled with the memory, the processor configured to:

receive, from a network entity, a configuration for conditional configured grant (CG) occasions for uplink transmission, each conditional CG occasion having multiple conditional CG resources;

monitor, within sensing windows configured for the conditional CG resources, for signals from one or more other UEs to determine availability of one or more of the conditional CG resources of a conditional CG occasion, wherein the one or more of the conditional CG resources are not available when a predefined sequence of the signals is detected within the sensing windows;

decide to perform uplink transmission on the one or more of the conditional CG resources when the one or more of the conditional CG resources are available;

perform a pseudo random selection to identify a subset of the conditional CG resources that are available based on the monitoring; and

randomly select one conditional CG resource from the subset of the conditional CG resources to perform uplink transmission.

24. The apparatus of claim 23 , wherein the processor determines that a conditional CG resource is unavailable if the processor detects, within a corresponding sensing window,

a reservation message, sent by another UE, reserving resources in the conditional CG resource of a future conditional CG occasion.

25. The apparatus of claim 23 , wherein the multiple conditional CG resources share a same sensing window.

26. An apparatus for wireless communications by a network entity, comprising:

a memory; and

a processor coupled with the memory, the processor configured to:

generate a configuration for conditional configured grant (CG) occasions for uplink transmission, each conditional CG occasion having multiple conditional CG resources;

send, to a user equipment (UE), the configuration to:

monitor within sensing windows configured for the conditional CG resources, for signals from one or more other UEs to determine availability of one or more of the conditional CG resources of a conditional CG occasion, wherein the one or more of the conditional CG resources are not available when a predefined sequence of the signals is detected within the sensing windows; and

decide to perform uplink transmission on the one or more of the conditional CG resources when the one or more of the conditional CG resources are available; and

send, to the UE, a retransmission command, wherein a size of the conditional CG resources that are available for the retransmission is dynamically increased based on the retransmission command.

27. The apparatus of claim 26 , wherein

a probability of the UE determining the conditional CG resources that are available for the retransmission is increased based on the retransmission command.