Determination of demodulation reference signal and phase tracking reference signal parameters

1. A method for wireless communications, comprising:

receiving radio resource control signaling configured with a first set of demodulation reference signal (DM-RS) parameters for transmission of an uplink data channel of a first type;

receiving downlink control information of a first format to activate the transmission of the uplink data channel;

selecting a second set of default DM-RS parameters for use with the first set of DM-RS parameters based at least in part on the first format of the received downlink control information, the second set of default DM-RS parameters comprising a DM-RS port, a number of DM-RS symbols, or a combination thereof; and

activating the transmission of the uplink data channel of the first type using the first set of DM-RS parameters and the second set of default DM-RS parameters.

2. The method of claim 1 , wherein the downlink control information of the first format comprises a downlink control information format 0_0 and the uplink data channel of the first type is a configured grant Type 2 physical uplink shared channel (PUSCH).

3. The method of claim 1 , wherein the DM-RS port comprises DM-RS port 0 and the number of DM-RS symbols is one.

4. The method of claim 1 , wherein the first set of DM-RS parameters comprises a DM-RS configuration type and additional DM-RS symbol locations.

5. The method of claim 1 , further comprising:

determining a configuration type of a DM-RS from the radio resource control signaling; and

determining additional DM-RS symbol locations from the radio resource control signaling.

6. The method of claim 1 , further comprising:

activating the transmission of the uplink data channel based at least in part on the received downlink control information of the first format, the first set of DM-RS parameters, or the second set of default DM-RS parameters, or a combination thereof.

7. The method of claim 1 , further comprising:

comparing at least one of the first set of DM-RS parameters or the second set of default DM-RS parameters to expected DM-RS parameters.

8. The method of claim 7 , further comprising:

overwriting one or more of the expected DM-RS parameters with one or more parameters of the first set of DM-RS parameters or the second set of default DM-RS parameters based at least in part on the comparing.

9. An apparatus for wireless communications, comprising:

a processor,

memory in electronic communication with the processor; and

instructions stored in the memory and executable by the processor to cause the apparatus to:

receive radio resource control signaling configured with a first set of demodulation reference signal (DM-RS) parameters for transmission of an uplink data channel of a first type;

receive downlink control information of a first format to activate the transmission of the uplink data channel;

select a second set of default DM-RS parameters for use with the first set of DM-RS parameters based at least in part on the first format of the received downlink control information, the second set of default DM-RS parameters comprising a DM-RS port, a number of DM-RS symbols, or a combination thereof; and

activate the transmission of the uplink data channel of the first type using the first set of DM-RS parameters and the second set of default DM-RS parameters.

10. The apparatus of claim 9 , wherein the downlink control information of the first format comprises a downlink control information format 0_0 and the uplink data channel of the first type is a configured grant Type 2 physical uplink shared channel (PUSCH).

11. The apparatus of claim 9 , wherein the DM-RS port comprises DM-RS port 0 and the number of DM-RS symbols is one.

12. The apparatus of claim 9 , wherein the first set of DM-RS parameters comprises a DM-RS configuration type and additional DM-RS symbol locations.

13. The apparatus of claim 9 , wherein the instructions are further executable by the processor to cause the apparatus to:

determine a configuration type of a demodulation reference signal from the radio resource control signaling; and

determine additional DM-RS symbol locations from the radio resource control signaling.

14. The apparatus of claim 9 , wherein the instructions are further executable by the processor to cause the apparatus to:

activate the transmission of the uplink data channel based at least in part on the received downlink control information of the first format, the first set of DM-RS parameters, or the second set of default DM-RS parameters, or a combination thereof.

15. The apparatus of claim 9 , wherein the instructions are further executable by the processor to cause the apparatus to:

compare at least one of the first set of DM-RS parameters or the second set of default DM-RS parameters to expected DM-RS parameters.

16. The apparatus of claim 15 , wherein the instructions are further executable by the processor to cause the apparatus to:

overwrite one or more of the expected DM-RS parameters with one or more parameters of the first set of DM-RS parameters or the second set of default DM-RS parameters based at least in part on the comparing.

17. An apparatus for wireless communications, comprising:

means for receiving radio resource control signaling configured with a first set of demodulation reference signal (DM-RS) parameters for transmission of an uplink data channel of a first type;

means for receiving downlink control information of a first format to activate the transmission of the uplink data channel;

means for selecting a second set of default DM-RS parameters for use with the first set of DM-RS parameters based at least in part on the first format of the received downlink control information, the second set of default DM-RS parameters comprising a DM-RS port, a number of DM-RS symbols, or a combination thereof; and

means for activating the transmission of the uplink data channel of the first type using the first set of DM-RS parameters and the second set of default DM-RS parameters.

18. The apparatus of claim 17 , wherein the downlink control information of the first format comprises a downlink control information format 0_0 and the uplink data channel of the first type is a configured grant Type 2 physical uplink shared channel (PUSCH).

19. The apparatus of claim 17 , wherein DM-RS port comprises DM-RS port 0 and the number of DM-RS symbols is one.

20. The apparatus of claim 17 , wherein first set of parameters comprises a DM-RS configuration type and additional DM-RS symbol locations.

21. The apparatus of claim 17 , further comprising:

means for determining a configuration type of a DM-RS from the radio resource control signaling; and

means for determining additional DM-RS symbol locations from the radio resource control signaling.

22. The apparatus of claim 17 , further comprising:

means for activating the transmission of the uplink data channel based at least in part on the received downlink control information of the first format, the first set of DM-RS parameters, or the second set of default DM-RS parameters, or a combination thereof.

23. The apparatus of claim 17 , further comprising:

means for comparing at least one of the first set of DM-RS parameters or the second set of default DM-RS parameters to expected DM-RS parameters.

24. The apparatus of claim 23 , further comprising:

means for overwriting one or more of the expected DM-RS parameters with at least one of the first set of DM-RS parameters or the second set of default DM-RS parameters based at least in part on the comparing.

25. A non-transitory computer-readable medium storing code for wireless communications, the code comprising instructions executable by a processor to:

receive radio resource control signaling configured with a first set of DM-RS parameters for transmission of an uplink data channel of a first type;

receive downlink control information of a first format to activate the transmission of the uplink data channel;

select a second set of default DM-RS parameters use with the first set of DM-RS parameters based at least in part on the first format of the received downlink control information, the second set of default DM-RS parameters comprising a DM-RS port, a number of DM-RS symbols, or a combination thereof; and

activate the transmission of the uplink data channel of the first type using the first set of DM-RS parameters and the second set of default DM-RS parameters.

26. The non-transitory computer-readable medium of claim 25 , wherein the downlink control information of the first format comprises a downlink control information format 0_0 and the uplink data channel of the first type is a configured grant Type 2 physical uplink shared channel (PUSCH).

27. The non-transitory computer-readable medium of claim 25 , wherein the DM-RS port comprises DM-RS port 0 and the number of DM-RS symbols is one.