Uplink carrier determination for random access procedure

1. A wireless device comprising:

one or more processors; and

memory storing instructions that, when executed by the one or more processors, cause the wireless device to:

receive one or more configuration parameters of a physical random access channel (PRACH) occasion for a random access procedure, wherein the PRACH occasion corresponds to a reference signal (RS);

determine an uplink carrier, from a normal uplink (NUL) carrier and a supplemental uplink (SUL) carrier, wherein the determination of the uplink carrier comprises comparing a first transmission power reduction value, associated with the RS and the NUL carrier, with a second transmission power reduction value, associated with the RS and the SUL carrier; and

transmit, via the PRACH occasion on the determined uplink carrier, a preamble for the random access procedure.

2. The wireless device of claim 1 , wherein to determine the uplink carrier, the instructions further cause the wireless device to:

determine the first transmission power reduction value, associated with the RS, for uplink transmission via the NUL carrier; and

determine the second transmission power reduction value, associated with the RS, for uplink transmission via the SUL carrier.

3. The wireless device of claim 1 , wherein the determined uplink carrier is:

the NUL carrier based on the first transmission power reduction value being less than or equal to the second transmission power reduction value; and

the SUL carrier based on the first transmission power reduction value being greater than the second transmission power reduction value.

4. The wireless device of claim 1 , wherein the uplink carrier is determined based on comparing the first transmission power reduction value to a threshold value.

5. The wireless device of claim 4 , wherein to determine the uplink carrier, the instructions further cause the wireless device to:

determine whether a combined value of a reference signal received power (RSRP) value, of the RS, and the first transmission power reduction value is greater than or equal to the threshold value.

6. The wireless device of claim 5 , wherein the uplink carrier is determined as:

the NUL carrier based on the combined value being greater than or equal to the threshold value; and

the SUL carrier based on the combined value being less than the threshold value.

7. The wireless device of claim 4 , wherein to determine the uplink carrier, the instructions further cause the wireless device to:

determine whether the first transmission power reduction value is less than or equal to the threshold value.

8. The wireless device of claim 7 , wherein the uplink carrier is determined as:

the NUL carrier based on the first transmission power reduction value being less than or equal to the threshold value; and

the SUL carrier based on the first transmission power reduction value being greater than the threshold value.

9. A base station comprising:

one or more processors; and

memory storing instructions that, when executed by the one or more processors, cause the base station to:

transmit, to a wireless device, one or more configuration parameters of a physical random access channel (PRACH) occasion for a random access procedure, wherein the PRACH occasion corresponds to a reference signal (RS); and

receive a preamble, for the random access procedure, via the PRACH occasion on an uplink carrier determined, from a normal uplink (NUL) carrier and a supplemental uplink (SUL) carrier, wherein the determination of the uplink carrier comprises comparing a first transmission power reduction value, associated with the RS and the NUL carrier, with a second transmission power reduction value, associated with the RS and the SUL carrier.

10. The base station of claim 9 , wherein the uplink carrier is determined based on:

the first transmission power reduction value, associated with the RS, for uplink transmission via the NUL carrier; and

the second transmission power reduction value, associated with the RS, for uplink transmission via the SUL carrier.

11. The base station of claim 9 , wherein the determined uplink carrier is:

the NUL carrier based on the first transmission power reduction value being less than or equal to the second transmission power reduction value; and

the SUL carrier based on the first transmission power reduction value being greater than the second transmission power reduction value.

12. The base station of claim 9 , wherein the uplink carrier is determined based on comparing the first transmission power reduction value to a threshold value.

13. The base station of claim 12 , wherein the determined uplink carrier is based on whether a combined value of a reference signal received power (RSRP) value, of the RS, and the first transmission power reduction value is greater than or equal to the threshold value.

14. The base station of claim 13 , wherein the uplink carrier is determined as:

the NUL carrier based on the combined value being greater than or equal to the threshold value; and

the SUL carrier based on the combined value being less than the threshold value.

15. The base station of claim 12 , wherein the determined uplink carrier is based on whether the first transmission power reduction value is less than or equal to the threshold value.

16. The base station of claim 15 , wherein the uplink carrier is determined as:

the NUL carrier based on the first transmission power reduction value being less than or equal to the threshold value; and

the SUL carrier based on the first transmission power reduction value less-being greater than the threshold value.

17. A non-transitory computer-readable medium comprising instructions that, when executed by one or more processors of a wireless device, cause the wireless device to:

receive one or more configuration parameters of a physical random access channel (PRACH) occasion for a random access procedure, wherein the PRACH occasion corresponds to a reference signal (RS);

determine an uplink carrier, from a normal uplink (NUL) carrier and a supplemental uplink (SUL) carrier, wherein the determination of the uplink carrier comprises comparing a first transmission power reduction value, associated with the RS and the NUL carrier, with a second transmission power reduction value, associated with the RS and the SUL carrier; and

transmit, via the PRACH occasion on the determined uplink carrier, a preamble for the random access procedure.

18. The non-transitory computer-readable medium of claim 17 , wherein the determined uplink carrier is:

the NUL carrier based on the first transmission power reduction value, for uplink transmission via the NUL carrier, being less than or equal to the second transmission power reduction value for uplink transmission via the SUL carrier; and

the SUL carrier based on the first transmission power reduction value being greater than the second transmission power reduction value.

19. The non-transitory computer-readable medium of claim 17 , wherein the uplink carrier is determined, as one of the NUL carrier and the SUL carrier, based on whether a combined value of a reference signal received power (RSRP) value, of the RS, and the first transmission power reduction value is greater than or equal to a threshold value.

20. The non-transitory computer-readable medium of claim 17 , wherein the uplink carrier is determined, as one of the NUL carrier and the SUL carrier, based on whether the first transmission power reduction value is less than or equal to a threshold value.