Signaling for uplink beam activation

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

receiving a configuration of uplink (UL) transmission configuration indicator (TCI) (UL-TCI) states and an activation of a subset of configured UL-TCI states;

receiving downlink control information (DCI) in a physical downlink control channel (PDCCH) scheduling a sounding reference signal (SRS) transmission with one or more UL-TCI states of the activated UL-TCI states; and

transmitting the SRS transmission based on the one or more UL-TCI states, wherein transmitting the SRS transmission comprises transmitting the SRS transmission with a quasi-co location (QCL) property associated with the one or more UL-TCI states, and wherein each UL-TCI state in the configured UL-TCI states corresponds to a first reference signal associated with indicating a UL transmit (Tx) beam configuration for a UL channel or a UL reference signal.

2. The method of claim 1 , wherein the configuration of UL-TCI states and the activation are received through a radio resource control (RRC) signal and a medium access control (MAC) control element (CE) (MAC-CE), respectively.

3. The method of claim 1 , wherein the first reference signal is further associated with a panel identifier (ID) of the UE.

4. The method of claim 1 , wherein the QCL property comprises at least one of a one or more port indications, a Doppler shift, a Doppler spread, an average delay, a delay spread, a spatial Tx parameter, or a spatial receive (Rx) parameter.

5. The method of claim 1 , wherein the first reference signal is one of a SRS, or a downlink (DL) reference signal (RS).

6. The method of claim 5 , wherein the DL RS is one of a channel state information (CSI) RS (CSI-RS), a demodulation RS (DM-RS) for at least one of a physical downlink shared channel (PDSCH) or a physical downlink control channel (PDCCH), or a synchronization signal/physical broadcast channel (PBCH) (SS/PBCH) block.

7. The method of claim 1 , wherein the DCI includes one or more codepoint values indicating the one or more UL-TCI states of the activated UL-TCI states.

8. The method of claim 7 , further comprising:

receiving a mapping between the activated UL-TCI states and a set of codepoint values, the one or more codepoint values being within the set of codepoint values.

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

a memory; and

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

receive a configuration of uplink (UL) transmission configuration indicator (TCI) (UL-TCI) states and an activation of a subset of configured UL-TCI states;

receive downlink control information (DCI) in a physical downlink control channel (PDCCH) scheduling a sounding reference signal (SRS) transmission with one or more UL-TCI states of the activated UL-TCI states; and

transmit the SRS transmission based on the one or more UL-TCI states, wherein to transmit the SRS transmission based on the one or more UL-TCI states, the at least one processor is further configured to transmit the SRS transmission with a quasi-co location (QCL) property associated with the one or more UL-TCI states, and wherein each UL-TCI state in the configured UL-TCI states corresponds to a first reference signal associated with indicating a UL transmit (Tx) beam configuration for a UL channel or a UL reference signal.

10. The apparatus of claim 9 , wherein the configuration of UL-TCI states and the activation are received through a radio resource control (RRC) signal and a medium access control (MAC) control element (CE) (MAC-CE), respectively.

11. The apparatus of claim 9 , wherein the QCL property comprises at least one of a one or more port indications, a Doppler shift, a Doppler spread, an average delay, a delay spread, a spatial transmit Tx parameter, or a spatial receive (Rx) parameter.

12. The apparatus of claim 9 , wherein the DCI includes one or more codepoint values indicating the one or more UL-TCI states of the activated UL-TCI states.

13. The apparatus of claim 12 , wherein the at least one processor is further configured to:

receive a mapping between the activated UL-TCI states and a set of codepoint values, the one or more codepoint values being within the set of codepoint values.

14. A method of wireless communication at a base station (BS), comprising:

transmitting, to a user equipment (UE), a configuration of uplink (UL) transmission configuration indicator (TCI) (UL-TCI) states and an activation of a subset of configured UL-TCI states;

transmitting, to the UE, downlink control information (DCI) in a physical downlink control channel (PDCCH) scheduling a sounding reference signal (SRS) transmission with one or more UL-TCI states of the activated UL-TCI states, the DCI scheduling the SRS transmission;

receiving the SRS transmission from the UE, the SRS transmission based on the one or more UL-TCI states, wherein the SRS transmission is associated with a quasi-co location (QCL) property associated with the one or more UL-TCI states, and wherein each UL-TCI state in the configured UL-TCI states corresponds to a first reference signal associated with indicating a UL transmit (Tx) beam configuration for a UL channel or a UL reference signal; and

demodulating the SRS transmission based on the one or more UL-TCI states.

15. The method of claim 14 , wherein the configuration of UL-TCI states and the activation are received through a radio resource control (RRC) signal and a medium access control (MAC) control element (CE) (MAC-CE), respectively.

16. The method of claim 14 , wherein the first reference signal is further associated with a panel identifier (ID) of the UE.

17. The method of claim 14 , wherein the QCL property comprises at least one of a one or more port indications, a Doppler shift, a Doppler spread, an average delay, a delay spread, a spatial transmit Tx parameter, or a spatial receive (Rx) parameter.

18. The method of claim 14 , wherein the first reference signal is one of SRS, or a downlink (DL) reference signal (RS).

19. The method of claim 18 , wherein the DL RS is one of a channel state information (CSI) RS (CSI-RS), a demodulation RS (DM-RS) for at least one of a physical downlink shared channel (PDSCH) or a physical downlink control channel (PDCCH), or a synchronization signal/physical broadcast channel (PBCH) (SS/PBCH) block.

20. The method of claim 14 , wherein the DCI includes one or more codepoint values indicating the one or more UL-TCI states of the activated UL-TCI states.

21. The method of claim 20 , further comprising:

transmitting a mapping between the activated UL-TCI states and a set of codepoint values, the one or more codepoint values being within the set of codepoint values.

22. An apparatus for wireless communication at a base station (BS), comprising:

a memory; and

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

transmit, to a user equipment (UE), a configuration of uplink (UL) transmission configuration indicator (TCI) (UL-TCI) states and an activation of a subset of configured UL-TCI states;

transmit, to the UE, downlink control information (DCI) in a physical downlink control channel (PDCCH) scheduling a sounding reference signal (SRS) transmission with one or more UL-TCI states of the activated UL-TCI states, the DCI scheduling the SRS transmission;

receive the SRS transmission from the UE, the SRS transmission being based on the one or more UL-TCI states, wherein the SRS transmission is associated with a quasi-co location (QCL) property associated with the one or more UL-TCI states, and wherein each UL-TCI state in the configured UL-TCI states corresponds to a first reference signal associated with indicating a UL transmit (Tx) beam configuration for a UL channel or a UL reference signal; and

demodulate the SRS transmission based on the one or more UL-TCI states.

23. The apparatus of claim 22 , wherein the DCI includes one or more codepoint values indicating the one or more UL-TCI states of the activated UL-TCI states.

24. The apparatus of claim 23 , wherein the at least one processor is further configured to:

transmit a mapping between the activated UL-TCI states and a set of codepoint values, the one or more codepoint values being within the set of codepoint values.