RACH power offset

1. A method comprising:

receiving, by a wireless device, at least one radio resource control message comprising one or more configuration parameters of a cell;

receiving, by the wireless device, a control order for transmission of a random access preamble via the cell;

determining, for the random access preamble, a transmission power based on a pathloss measurement, wherein:

when the one or more configuration parameters comprise one or more parameters of a channel state information reference signal (CSI-RS) for the cell:

the pathloss measurement is based on the CSI-RS; and

the determining the transmission power employs a power offset value indicated by the one or more configuration parameters; and

when the one or more configuration parameters do not comprise CSI-RS parameters for the cell:

the pathloss measurement is based on at least one synchronization signal; and

the determining the transmission power does not employ the power offset value; and

transmitting the random access preamble based on the transmission power.

2. The method of claim 1 , wherein the CSI-RS is a periodic CSI-RS.

3. The method of claim 1 , wherein the one or more parameters of the CSI-RS indicate a periodicity of the CSI-RS.

4. The method of claim 1 , wherein the one or more parameters of the CSI-RS indicate at least one of one or more CSI-RS subcarriers of resource elements or a CSI-RS sequence.

5. The method of claim 1 , wherein the at least one radio resource control message comprises at least one of a reference signal power value, a preamble base station received target power, or a configured wireless device transmit power for the cell.

6. The method of claim 1 , wherein the transmission power is based on a sum of a preamble base station received target power and a value of the pathloss measurement.

7. The method of claim 6 , wherein the value of the pathloss measurement is based on a reference signal power value minus a measured received power value of a reference signal, wherein:

when the one or more configuration parameters comprise one or more parameters of the CSI-RS for the cell: the reference signal is the CSI-RS; and

when the one or more configuration parameters do not comprise CSI-RS parameters for the cell: the reference signal is at least one synchronization signal.

8. The method of claim 1 , wherein the determining the transmission power is further based on a reference signal power value.

9. The method of claim 1 , wherein the transmission power employs the value of the pathloss measurement determined based on a received power of the CSI-RS.

10. The method of claim 1 , wherein when the one or more configuration parameters comprise one or more parameters of the CSI-RS, the transmitting the random access preamble uses at least one random access channel, wherein the at least one radio resource control message indicates:

an association between one or more synchronization signals and the CSI-RS; and

an association between the at least one random access channel and the one or more synchronization signals.

11. A method comprising:

receiving, by a wireless device, at least one radio resource control message comprising a reference signal power value of a synchronization signals and physical broadcast channel (SS/PBCH) block;

receiving a control order for transmission of a random access preamble;

determining a transmission power for the random access preamble, wherein:

in response to a determination that the wireless device is configured with a channel state information reference signal (CSI-RS), the determining the transmission power is based on the reference signal power value and a power offset value, wherein the power offset value is associated with the CSI-RS and is indicated in the at least one radio resource control message; and

in response to a determination that the wireless device is not configured with the CSI-RS, the determining the transmission power is:

based on the reference signal power value and at least one first reference signal received power (RSRP) measurement of the SS/PBCH block; and

not based on the power offset value associated with the CSI-RS; and

transmitting the random access preamble based on the transmission power.

12. The method of claim 11 , wherein in response to the determination that the wireless device is configured with the CSI-RS, the determining the transmission power is further based on:

a preamble received target power broadcasted in a system information block; and

at least one second RSRP measurement.

13. The method of claim 11 , wherein in response to the determination that the wireless device is not configured with CSI-RS, the determining the transmission power is further based on a preamble received target power.

14. The method of claim 11 , wherein the CSI-RS is a periodic CSI-RS and one or more parameters of the CSI-RS indicate a periodicity of the CSI-RS.

15. The method of claim 11 , wherein one or more parameters of the CSI-RS indicate at least one of one or more CSI-RS subcarriers of resource elements or a CSI-RS sequence.

16. The method of claim 11 , wherein the at least one radio resource control message comprises at least one of a reference signal power value, a preamble base station received target power, or a configured wireless device transmit power for a cell.

17. The method of claim 11 , wherein the transmission power is further based on a sum of a preamble base station received target power and a value of a pathloss measurement.

18. The method of claim 17 , wherein the value of the pathloss measurement is based on the reference signal power value minus a measured received power value of a reference signal, wherein the reference signal is:

the CSI-RS when the wireless device is configured with the CSI-RS; and

the SS/PBCH block when the wireless device is not configured with the CSI-RS.

19. The method of claim 17 , wherein the transmission power employs the value of the pathloss measurement determined based on a received power of the CSI-RS.

20. The method of claim 11 , wherein in response to the determination that the wireless device is configured with the CSI-RS, the transmitting the random access preamble uses at least one random access channel, wherein the at least one radio resource control message indicates:

an association between one or more synchronization signals and the CSI-RS; and

an association between the at least one random access channel and the one or more synchronization signals.