Application of uplink transmission configuration indicator state with downlink reference signal to codebook based transmissions

1. An apparatus of wireless communications, comprising:

at least one processor; and

memory coupled to the at least one processor, the memory comprising code executable by the at least one processor to cause the apparatus to:

receive, from a network entity, signaling of an uplink transmission configuration indicator (TCI) state for a target codebook based uplink transmission;

determine uplink transmission parameters;

determine if the TCI state has a source downlink reference signal (RS); and

decide whether to apply at least one of the uplink transmission parameters or the TCI state to the codebook based uplink transmission based on the determination.

2. The apparatus of claim 1 , wherein the codebook based uplink transmission comprises a physical uplink shared channel (PUSCH).

3. The apparatus of claim 1 , wherein:

the uplink transmission parameters are determined based on a first downlink RS prior to receiving the TCI state;

the TCI state has a second downlink RS as a source downlink RS; and

deciding whether to apply at least one of the uplink transmission parameters or the TCI state to the codebook based uplink transmission depends, at least in part, on the first downlink RS and the second downlink RS.

4. The apparatus of claim 3 , wherein a type of at least one of the first downlink RS or the second downlink RS comprises at least one of:

a first QCL type that indicates QCL assumptions regarding Doppler shift, Doppler spread, average delay, and delay spread;

a second QCL type that indicates QCL assumptions regarding Doppler shift and Doppler spread;

a third QCL type that indicates Doppler shift and average delay; or

a fourth QCL type that indicates QCL assumptions regarding spatial relations.

5. The apparatus of claim 3 , wherein the decision is to use previously determined transmission parameters if the first and second downlink RS are a same type.

6. The apparatus of claim 3 , wherein:

the transmission parameters are received from the network entity; and

the decision is to use the transmission parameters if the first and second downlink RS are of different types.

7. The apparatus of claim 3 , wherein the uplink transmission parameters are determined based on a first downlink RS prior to receiving the TCI state.

8. The apparatus of claim 1 , wherein the code is executable by the at least one processor to further cause the apparatus to:

transmit sounding reference signals (SRS) to the network entity; and

receive the uplink transmission parameters from the network entity based on the SRS,

wherein the decision is to apply the uplink transmission parameters and UL TCI state for the codebook based uplink transmission.

9. The apparatus of claim 8 , wherein at least some of the uplink transmission parameters are signaled separately from the UL TCI state.

10. The apparatus of claim 1 , wherein the uplink transmission parameters comprise at least one of a transmission rank indication (TM), transmit precoding matrix indicator (TPMI), or SRS resource indicator (SRI).

11. An apparatus of wireless communications, comprising:

at least one processor; and

memory coupled to the at least one processor, the memory comprising code executable by the at least one processor to cause the apparatus to:

send, to a user equipment (UE), signaling of an uplink transmission configuration indicator (TCI) state for a target codebook based uplink transmission;

determine whether the UE applied at least one of uplink transmission parameters or the TCI state to the codebook based uplink transmission, based on whether the TCI state has a source downlink reference signal (RS); and

process the codebook based uplink transmission in accordance with the determination.

12. The apparatus of claim 11 , wherein the codebook based uplink transmission comprises a physical uplink shared channel (PUSCH).

13. The apparatus of claim 11 , wherein:

the uplink transmission parameters are determined based on a first downlink RS prior to sending the TCI state;

the TCI state has a second downlink RS as a source downlink RS; and

determining whether the UE applied at least one of the uplink transmission parameters or the TCI state to the codebook based uplink transmission depends, at least in part, on the first downlink RS and the second downlink RS.

14. The apparatus of claim 13 , wherein a type of at least one of the first downlink RS or the second downlink RS comprises at least one of:

a first QCL type that indicates QCL assumptions regarding Doppler shift, Doppler spread, average delay, and delay spread;

a second QCL type that indicates QCL assumptions regarding Doppler shift and Doppler spread;

a third QCL type that indicates Doppler shift and average delay; or

a fourth QCL type that indicates QCL assumptions regarding spatial relations.

15. The apparatus of claim 13 , wherein the determination is that the UE used previously determined transmission parameters if the first and second downlink RS are a same type.

16. The apparatus of claim 13 , wherein:

the transmission parameters are transmitted from the apparatus; and

the determination is the UE used the transmission parameters if the first and second downlink RS are of different types.

17. The apparatus of claim 11 , wherein the code is executable by the at least one processor to further cause the apparatus to:

receive sounding reference signals (SRS) from the UE; and

transmit the uplink transmission parameters to the UE based on the SRS, wherein the determination is the UE applied the uplink transmission parameters and UL TCI state for the codebook based uplink transmission.

18. The apparatus of claim 17 , wherein at least some of the uplink transmission parameters are signaled separately from the UL TCI state.

19. The apparatus of claim 11 , wherein the uplink transmission parameters comprise at least one of a transmission rank indication (TM), transmit precoding matrix indicator (TPMI), or SRS resource indicator (SRI).

20. A method for wireless communications at a user equipment, comprising:

receiving, from a network entity, signaling of an uplink transmission configuration indicator (TCI) state for a target codebook based uplink transmission;

determining uplink transmission parameters;

determining if the TCI state has a source downlink reference signal (RS); and

deciding whether to apply at least one of the uplink transmission parameters or the TCI state to the codebook based uplink transmission based on the determination.