Cross-beam coupling reporting

1 . An apparatus for wireless communication at a user equipment (UE), comprising:

one or more memories; and

one or more processors coupled to the one or more memories, the one or more processors configured to cause the UE to:

receive, via a receive beam, a first reference signal from a first transmission reception point (TRP);

receive, via the receive beam, a second reference signal from a second TRP; and

transmit an indication of a difference between a first measurement of the first reference signal received on the receive beam and a second measurement of the second reference signal received on the receive beam.

2 . The apparatus of claim 1 ,

wherein the receive beam is a first receive beam; and

wherein the one or more processors are further configured to cause the UE to:

receive, via a second receive beam, the first reference signal from the first TRP;

receive, via the second receive beam, the second reference signal from the second TRP; and

transmit an indication of a difference between a third measurement of the second reference signal received via the second receive beam and a fourth measurement of the first reference signal received via the second receive beam.

3 . The apparatus of claim 2 ,

wherein the first receive beam is associated with a first antenna module of the apparatus;

and

wherein the second receive beam is associated with a second antenna module of the apparatus.

4 . The apparatus of claim 2 ,

wherein the one or more processors are further configured to cause the UE to:

transmit an indication of the first measurement and an indication of the third measurement.

5 . The apparatus of claim 1 ,

wherein the first reference signal is received from a first transmit beam of the first TRP;

wherein the second reference signal is received from a second transmit beam of the second TRP; and

wherein the indication of the difference between the first measurement and the second measurement comprises an indication of cross-beam coupling between the first transmit beam and the second transmit beam.

6 . The apparatus of claim 5 ,

wherein the first transmit beam and the second transmit beam are wide beams or narrow beams.

7 . The apparatus of claim 5 ,

wherein the first transmit beam and the second transmit beam are narrow beams.

8 . The apparatus of claim 1 ,

wherein the first measurement comprises a first reference signal received power (RSRP) measurement of the first reference signal; and

wherein the second measurement comprises a second RSRP measurement of the second reference signal.

9 . The apparatus of claim 8 ,

wherein the difference between the first measurement and the second measurement is quantized to a closest configured reporting value.

10 . The apparatus of claim 1 ,

wherein selection of the first reference signal and the second reference signal is based at least in part on a UE implementation for the apparatus.

11 . The apparatus of claim 1 ,

wherein the difference between the first measurement and the second measurement is based at least in part on a user equipment (UE) implementation for the apparatus.

12 . The apparatus of claim 1 ,

wherein the difference between the first measurement and the second measurement is based at least in part on selection of the first reference signal and the second reference signal.

13 . The apparatus of claim 1 ,

wherein the one or more processors are further configured to cause the UE to:

transmit an indication of the first measurement,

wherein a measurement error for the first measurement is less than a threshold margin.

14 . The apparatus of claim 1 ,

wherein the first reference signal is included in a first reference signal set associated with a first plurality of narrow beams of the first TRP;

wherein the second reference signal is included in a second reference signal set associated with a second plurality of narrow beams of the second TRP; and

wherein the first reference signal set and the second reference signal set are frequency division multiplexed.

15 . The apparatus of claim 14 ,

wherein the one or more processors are further configured to cause the UE to:

receive an indication of a quantity of reference signal pairs for cross-beam coupling reporting,

wherein each of the reference signal pairs includes one reference signal from the first reference signal set and one reference signal from the second reference signal set.

16 . A first apparatus for wireless communication at a network node, comprising:

one or more memories; and

one or more processors, coupled to the one or more memories, configured to cause the network node to:

provide a first reference signal for a user equipment (UE); and

obtain an indication of a difference between a first measurement of the first reference signal, associated with a receive beam of the UE and a second measurement of a second reference signal, associated with the receive beam of the UE.

17 . The first apparatus of claim 16 ,

wherein the difference between the first measurement and the second measurement is associated with a first receive beam of the UE; and

wherein the one or more processors are further configured to cause the network node to:

obtain an indication of a difference between a third measurement of the second reference signal and a fourth measurement of the first reference signal,

wherein the difference between the third measurement and the fourth measurement is associated with a second receive beam of the UE.

18 . The first apparatus of claim 17 ,

wherein the one or more processors are further configured to cause the network node to:

obtain an indication of the first measurement and an indication of the third measurement.

19 . The first apparatus of claim 16 ,

wherein the first reference signal is associated with a first transmit beam of the first apparatus;

wherein the second reference signal is associated with a second transmit beam of the UE; and

wherein the indication of the difference between the first measurement and the second measurement comprises an indication of cross-beam coupling between the first transmit beam and the second transmit beam.

20 . The first apparatus of claim 16 ,

wherein the first measurement comprises a first reference signal received power (RSRP) measurement of the first reference signal; and

wherein the second measurement comprises a second RSRP measurement of the second reference signal.

21 . The first apparatus of claim 20 ,

wherein the difference between the first measurement and the second measurement is quantized to a nearest configured reporting value.

22 . The first apparatus of claim 16 ,

wherein selection of the first reference signal is among a plurality of reference signals transmitted by the first apparatus on a plurality of transmit beams.

23 . The first apparatus of claim 16 ,

wherein the difference between the first measurement and the second measurement is based at least in part on selection of the first reference signal and the second reference signal.

24 . The first apparatus of claim 16 ,

wherein the one or more processors are further configured to cause the network node to:

obtain an indication of the first measurement,

wherein a measurement error for the first measurement is less than a threshold margin.

25 . The first apparatus of claim 16 ,

wherein the first reference signal is included in a first reference signal set associated with a first plurality of narrow beams of the first apparatus;

wherein the second reference signal is included in a second reference signal set associated with a second plurality of narrow beams of the UE; and

wherein the first reference signal set and the second reference signal set are frequency division multiplexed.

26 . The first apparatus of claim 25 ,

wherein the one or more processors are further configured to cause the network node to:

provide an indication of a quantity of reference signal pairs for which to report cross-beam coupling,

wherein each of the reference signal pairs includes one reference signal from the first reference signal set and one reference signal from the second reference signal set.

27 . A method of wireless communication performed at a user equipment (UE), comprising:

receiving, via a receive beam, a first reference signal from a first transmission reception point (TRP);

receiving, via the receive beam, a second reference signal from a second TRP; and

transmitting an indication of a difference between a first measurement of the first reference signal received on a receive beam and a second measurement of a second reference signal received on the receive beam.

28 . The method of claim 27 ,

wherein the receive beam is a first receive beam; and

wherein the method further comprises:

receiving, via a second receive beam, the first reference signal from the first TRP;

receiving, via the second receive beam, the second reference signal from the second TRP; and

transmitting an indication of a difference between a third measurement of the second reference signal received via the second receive beam and a fourth measurement of the first reference signal received via the second receive beam.

29 . A method of wireless communication performed at a first network node, comprising:

providing a first reference signal for a user equipment (UE); and

obtaining an indication of a difference between a first measurement of the first reference signal, associated with a receive beam of the UE, and a second measurement of a second reference signal, associated with the receive beam of the UE.

30 . The method of claim 29 ,

wherein the difference between the first measurement and the second measurement is associated with a first receive beam of the UE; and

wherein the method further comprises:

receiving, from the UE, an indication of a difference between a third measurement of the second reference signal and a fourth measurement of the first reference signal,

wherein the difference between the third measurement and the fourth measurement is associated with a second receive beam of the UE.