Feedback for beam changes

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

receiving, from a base station, a downlink transmission on a downlink data channel including data and an indication of a beam switch;

transmitting first acknowledgement (ACK) feedback to the base station in response to receiving the data; and

transmitting, on a same beam set as the first ACK feedback, second ACK feedback to the base station in response to receiving the indication of the beam switch, the second ACK feedback being separate from the first ACK feedback.

2. The method of claim 1 , wherein the downlink transmission includes a medium access control (MAC) control element (CE) that includes the indication of the beam switch.

3. The method of claim 1 , wherein the transmitting second ACK feedback to the base station in response to receiving the indication of the beam switch comprises:

transmitting second ACK feedback to the base station in response to receiving the indication of the beam switch after a first time period following the downlink transmission on the downlink data channel.

4. The method of claim 3 , wherein the first time period is one of received from the base station or preconfigured at the UE.

5. The method of claim 1 , wherein the second ACK feedback is at least one of:

transmitted on a second set of resources different from a first set of resources on which the first ACK feedback is transmitted,

transmitted in a second format different from a first format in which the first ACK feedback is transmitted,

transmitted as a second type different from a first type as the first ACK feedback is transmitted, or

transmitted using a second transmission method different from a first transmission method used for transmitting the first ACK feedback.

6. The method of claim 1 , wherein the second ACK feedback is transmitted based on a set of parameters that includes at least one of:

a configuration associated with repeated transmissions of the second ACK feedback,

a set of resources on an uplink control channel that carries the second ACK feedback, or

a format of the uplink control channel that carries the second ACK feedback.

7. The method of claim 6 , wherein the set of parameters is preconfigured at the UE.

8. The method of claim 6 , further comprising:

receiving, from the base station, information indicating the set of parameters.

9. The method of claim 8 , wherein the information indicating the set of parameters is received via one of radio resource control (RRC) signaling or the indication of the beam switch.

10. The method of claim 1 , further comprising:

receiving, from the base station, information activating the indication of the beam switch on the downlink data channel.

11. The method of claim 10 , wherein the information activating the indication of the beam switch on the downlink data channel is received via downlink control information (DCI) that is one of specific to the UE or common to a group of UEs.

12. A method of wireless communication at a base station, comprising:

transmitting, to a user equipment (UE), a downlink transmission on a downlink data channel including data and an indication of a beam switch;

receiving first acknowledgement (ACK) feedback from the UE in response to transmitting the data; and

receiving, on a same beam set as the first ACK feedback, second ACK feedback from the UE in response to transmitting the indication of the beam switch, the second ACK feedback being separate from the first ACK feedback.

13. The method of claim 12 , wherein the downlink transmission includes a medium access control (MAC) control element (CE) that includes the indication of the beam switch.

14. The method of claim 12 , wherein the receiving the second ACK feedback from the UE in response to transmitting the indication of the beam switch comprises:

receiving second ACK feedback from the UE in response to transmitting the indication of the beam switch after a first time period following the downlink transmission on the downlink data channel.

15. The method of claim 14 , wherein the first time period is one of transmitted to the UE or preconfigured at the UE.

16. The method of claim 12 , wherein the second ACK feedback is at least one of:

received on a second set of resources different from a first set of resources on which the first ACK feedback is received,

received in a second format different from a first format in which the first ACK feedback is received,

received as a second type different from a first type as the first ACK feedback is received, or

received according to a second transmission method different from a first transmission method used for transmitting the first ACK feedback.

17. The method of claim 12 , wherein the second ACK feedback is received based on a set of parameters that includes at least one of:

a configuration associated with repeated transmissions of the second ACK feedback,

a set of resources on an uplink control channel that carries the second ACK feedback, or

a format of the uplink control channel that carries the second ACK feedback.

18. The method of claim 17 , further comprising:

transmitting, to the UE, information indicating the set of parameters.

19. The method of claim 18 , wherein the information indicating the set of parameters is transmitted via one of radio resource control (RRC) signaling or the indication of the beam switch.

20. The method of claim 12 , further comprising:

transmitting, to the UE, information activating the indication of the beam switch on the downlink data channel.

21. The method of claim 20 , wherein the information activating the indication of the beam switch on the downlink data channel is transmitted via downlink control information (DCI) that is one of specific to the UE or common to a group of UEs.

22. 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, from a base station, a downlink transmission on a downlink data channel including data and an indication of a beam switch;

transmit first acknowledgement (ACK) feedback to the base station in response to reception of the data; and

transmit, on a same beam set as the first ACK feedback, second ACK feedback to the base station in response to reception of the indication of the beam switch, the second ACK feedback being separate from the first ACK feedback.

23. The apparatus of claim 22 , wherein the downlink transmission includes a medium access control (MAC) control element (CE) that includes the indication of the beam switch.

24. The apparatus of claim 22 , wherein to transmit the second ACK feedback to the base station in response to reception of the indication of the beam switch, the at least one processor is configured to:

transmit second ACK feedback to the base station in response to reception of the indication of the beam switch after a first time period following the downlink transmission on the downlink data channel.

25. The apparatus of claim 24 , wherein the first time period is one of received from the base station or preconfigured at the UE.

26. The apparatus of claim 22 , wherein the second ACK feedback is at least one of:

transmitted on a second set of resources different from a first set of resources on which the first ACK feedback is transmitted,

transmitted in a second format different from a first format in which the first ACK feedback is transmitted,

transmitted as a second type different from a first type as the first ACK feedback is transmitted, or

transmitted using a second transmission apparatus different from a first transmission apparatus used for transmitting the first ACK feedback.

27. The apparatus of claim 22 , wherein the second ACK feedback is transmitted based on a set of parameters that includes at least one of:

a configuration associated with repeated transmissions of the second ACK feedback,

a set of resources on an uplink control channel that carries the second ACK feedback, or

a format of the uplink control channel that carries the second ACK feedback.

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, to a user equipment (UE), a downlink transmission on a downlink data channel including data and an indication of a beam switch;

receive first acknowledgement (ACK) feedback from the UE in response to transmission of the data; and

receive, on a same beam set as the first ACK feedback, second ACK feedback from the UE in response to transmission of the indication of the beam switch, the second ACK feedback being separate from the first ACK feedback.

29. The apparatus of claim 28 , wherein the downlink transmission includes a medium access control (MAC) control element (CE) that includes the indication of the beam switch.

30. The apparatus of claim 28 , wherein to receive the second ACK feedback from the UE in response to transmitting the indication of the beam switch, the at least one processor is configured to:

receive second ACK feedback from the UE in response to transmitting the indication of the beam switch after a first time period following the downlink transmission on the downlink data channel.