Acknowledgement-based link adaptation with listen-before-talk procedures

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

receiving a pre-grant message from a base station on a wireless channel;

determining an interference level associated with the wireless channel;

determining an applicable CSI report from a plurality of CSI reports based on comparison of an interfering spatial signature to respective spatial signatures associated with the plurality of CSI reports, wherein the interfering spatial signature is based on the interference on the wireless channel; and

indicating the interference level in an acknowledgement (ACK) message to the base station in response to the pre-grant message, wherein the ACK message includes the applicable CSI report.

2. The method of claim 1 , wherein the interference level is determined based on a measurement indicative of interference proximate to the UE on the wireless channel, the measurement being determined in a duration associated with at least one of a clear channel assessment (CCA) or an extended CCA (eCCA).

3. The method of claim 2 , further comprising:

determining the measurement indicative of interference proximate to the UE on the wireless channel,

wherein the interference level is based on the measurement indicative of the interference proximate to the UE on the wireless channel.

4. The method of claim 3 , further comprising:

refraining from transmitting the ACK message responsive to the pre-grant message to the base station when the measurement satisfies an energy detection (ED) threshold,

wherein absence of the ACK message responsive to the pre-grant message indicates the interference level to the base station.

5. The method of claim 3 , further comprising:

transmitting the ACK message responsive to the pre-grant message to the base station, wherein the ACK message indicates the interference level based on the measurement indicative of the interference proximate to the UE on the wireless channel.

6. The method of claim 5 , further comprising:

quantizing the measurement based on comparison of the measurement to a plurality of thresholds,

wherein the interference level is determined based on quantizing the measurement.

7. The method of claim 6 , further comprising:

receiving, from the base station, information configuring one or more of the plurality of thresholds to a respective value.

8. The method of claim 5 , further comprising:

receiving a set of channel state information (CSI) reference signals (RSs) from the base station on the wireless channel; and

generating at least one CSI report based on receiving at least a subset of the set of CSI-RSs,

wherein the ACK message includes the at least one CSI report.

9. The method of claim 8 , wherein the at least one CSI report comprises at least one of a short CSI report or fast CSI report.

10. The method of claim 8 , wherein the set of CSI-RSs is received on a first set of resources at least partially overlapping with a second set of resources on which the pre-grant message is received.

11. The method of claim 8 , wherein the pre-grant message comprises a trigger for aperiodic CSI reporting, and the at least one CSI report is included in the ACK message based on the trigger for aperiodic CSI reporting.

12. The method of claim 8 , further comprising:

determining the interfering spatial signature based on the interference on the wireless channel in response to receiving the pre-grant message, wherein the at least one CSI report comprises the plurality of CSI reports generated before the pre-grant message is received.

13. A method of wireless communication by a base station, comprising:

transmitting a pre-grant message to a user equipment (UE) on a wireless channel;

detecting for an acknowledgement (ACK) message responsive to the pre-grant message from the UE; and

determining an interference level associated with the wireless channel proximate to the UE based on detecting for the ACK message, wherein the ACK message includes a CSI report based on comparison of an interfering spatial signature to respective spatial signatures associated with a plurality of CSI reports, the interfering spatial signature based on the interference on the wireless channel.

14. The method of claim 13 , wherein the determining the interference level associated with the wireless channel proximate to the UE based on detecting for the ACK message comprises:

determining that the ACK message is absent based on detecting for the ACK message; and

determining that the interference level comprises an energy measurement that is greater than or equal to an energy detection (ED) threshold when the ACK message is determined to be absent from the wireless channel.

15. The method of claim 13 , wherein the interference level is based on at least one of a clear channel assessment (CCA) procedure by the UE or an extended CCA (eCCA) by the UE, and the pre-grant message comprises information configuring a duration of the at least one of the CCA procedure or the eCCA procedure.

16. The method of claim 13 , further comprising:

receiving the acknowledgement (ACK) message responsive to the pre-grant message from the UE based on detecting for the ACK message, wherein the ACK message comprises an indication of the interference level.

17. The method of claim 16 , wherein the indication of the interference level comprises a quantized value.

18. The method of claim 17 , further comprising:

transmitting, to the UE, information configuring one or more of a plurality of thresholds to a respective value,

wherein the quantized value is based on the plurality of thresholds.

19. The method of claim 16 , further comprising:

transmitting a set of channel state information (CSI) reference signals (RSs) to the UE on the wireless channel, and

wherein the ACK message further comprises at least one CSI report that is based on at least a subset of the set of CSI-RSs.

20. The method of claim 19 , wherein the at least one CSI report comprises at least one of a short CSI report or fast CSI report.

21. The method of claim 19 , wherein the set of CSI-RSs is transmitted on a first set of resources at least partially overlapping with a second set of resources on which the pre-grant message is transmitted.

22. The method of claim 19 , wherein the pre-grant message comprises a trigger for aperiodic CSI reporting, and the at least one CSI report is included in the ACK message based on the trigger for aperiodic CSI reporting.

23. The method of claim 19 , wherein the ACK message further comprises an indication of an interfering spatial signature associated with the at least one CSI report.

24. An apparatus for wireless communication by a user equipment (UE), comprising:

a memory; and

at least one processor coupled to the memory and configured to:

receive a pre-grant message from a base station on a wireless channel;

determine an interference level associated with the wireless channel;

determine an applicable CSI report from a plurality of CSI reports based on comparison of an interfering spatial signature to respective spatial signatures associated with the plurality of CSI reports, wherein the interfering spatial signature is based on the interference on the wireless channel; and

indicate the interference level in an acknowledgement (ACK) message to the base station in response to the pre-grant message, wherein the ACK message includes the applicable CSI report.

25. The apparatus of claim 24 , wherein the interference level is determined based on a measurement indicative of interference proximate to the UE on the wireless channel, the measurement being determined in a duration associated with at least one of a clear channel assessment (CCA) or an extended CCA (eCCA).

26. The apparatus of claim 25 , wherein the at least one processor is further configured to:

determine the measurement indicative of interference proximate to the UE on the wireless channel,

wherein the interference level is based on the measurement indicative of the interference proximate to the UE on the wireless channel.

27. The apparatus of claim 26 , wherein the at least one processor is further configured to:

transmitting the ACK message responsive to the pre-grant message to the base station, wherein the ACK message indicates the interference level based on the measurement indicative of the interference proximate to the UE on the wireless channel.

28. An apparatus for wireless communication by a base station, comprising:

a memory; and

at least one processor coupled to the memory and configured to:

transmit a pre-grant message to a user equipment (UE) on a wireless channel;

detect for an acknowledgement (ACK) message responsive to the pre-grant message from the UE; and

determine an interference level associated with the wireless channel proximate to the UE based on detecting for the ACK message, wherein the ACK message includes a CSI report based on comparison of an interfering spatial signature to respective spatial signatures associated with a plurality of CSI reports, the interfering spatial signature based on the interference on the wireless channel.

29. The apparatus of claim 28 , wherein the determination of the interference level associated with the wireless channel proximate to the UE based on detecting for the ACK message comprises to:

determine that the ACK message is absent based on the detection for the ACK message; and

determine that the interference level comprises an energy measurement that is greater than or equal to an energy detection (ED) threshold when the ACK message is determined to be absent from the wireless channel.

30. The apparatus of claim 28 , wherein the at least one processor is further configured to:

receive the acknowledgement (ACK) message responsive to the pre-grant message from the UE based on detecting for the ACK message, wherein the ACK message comprises an indication of the interference level.