Random access procedure
A wireless device receives message(s) from a base station comprising configuration parameters of a first uplink bandwidth part of a cell. The configuration parameters comprise: a bandwidth part configuration parameter of the first uplink bandwidth part, and random access channel parameters of a random access channel resource. A preamble is transmitted via the random access channel resource on the first uplink bandwidth part. A random access radio network temporary identifier (RA-RNTI) is determined based on the bandwidth part configuration parameter and one or more of the random access channel parameters. A downlink control channel is monitored for a downlink control information addressed to the RA-RNTI in response to the determining. The downlink control information indicates a downlink radio resource of a random access response is received. The random access response is received via the downlink radio resource in response to the downlink control information.
1. A method comprising:
receiving, by a wireless device from a base station, one or more messages comprising configuration parameters of a first uplink bandwidth part of a cell, wherein the configuration parameters comprise:
a bandwidth part configuration parameter of the first uplink bandwidth part; and
random access channel parameters of a random access channel resource;
transmitting a preamble via the random access channel resource on the first uplink bandwidth part;
determining a random access radio network temporary identifier (RA-RNTI) based on the bandwidth part configuration parameter of the first uplink bandwidth part and one or more of the random access channel parameters;
monitoring, in response to the determining, a downlink control channel for a downlink control information addressed to the RA-RNTI;
receiving the downlink control information indicating a downlink radio resource of a random access response; and
receiving the random access response via the downlink radio resource in response to the downlink control information.
2. The method of claim 1 , wherein the cell is a primary cell of a plurality of cells.
3. The method of claim 1 , wherein the cell is a secondary cell of a plurality of cells.
4. The method of claim 1 , wherein the bandwidth part configuration parameter comprises a bandwidth part index of the first uplink bandwidth part.
5. The method of claim 1 , wherein the bandwidth part configuration parameter comprises a bandwidth value of the first uplink bandwidth part.
6. The method of claim 1 , further comprising initiating a random access procedure on the first uplink bandwidth part.
7. The method of claim 1 , wherein the one or more of the random access channel parameters comprise a time resource parameter and a frequency resource parameter.
8. The method of claim 1 , wherein the random access channel parameters of the random access channel resource comprise at least one of:
a preamble index of a preamble;
a preamble format;
a preamble transmission numerology;
a time and radio resource parameter;
a frequency radio resource parameter; and
parameters of power setting.
9. The method of claim 1 , wherein the transmitting the preamble is in response to receiving a first downlink control information comprising at least one of:
a preamble index identifying the preamble; and
a random access channel resource index identifying the random access channel resource.
10. The method of claim 1 , wherein the wireless device determines the RA-RANTI further based on a cell identifier of the cell.
11. The method of claim 1 , wherein the random access response comprises a preamble index identifying the preamble.
12. The method of claim 1 , wherein the random access response comprises an uplink grant on the first uplink bandwidth part.
13. The method of claim 1 , wherein the cell comprises a plurality of uplink bandwidth parts comprising the first uplink bandwidth part and a second uplink bandwidth part.
14. The method of claim 13 , wherein the second uplink bandwidth part of the plurality of the uplink bandwidth parts is configured with a first bandwidth part configuration parameter and first random access channel parameters of a first random access channel resource.
15. The method of claim 1 , wherein the bandwidth part configuration parameter comprises a frequency location parameter of the first uplink bandwidth part.
16. The method of claim 15 , wherein the frequency location parameter is a resource block starting position parameter of the first uplink bandwidth part.
17. The method of claim 16 , wherein the resource block starting position parameter comprises an offset value in number of physical resource blocks between a frequency reference point of the cell and a first usable subcarrier of the first uplink bandwidth part.
18. The method of claim 1 , wherein the transmitting the preamble is in response to initiating a contention-based random access procedure.
19. The method of claim 18 , further comprising selecting the first uplink bandwidth part from the first uplink bandwidth part and the second uplink bandwidth part of the plurality of the uplink bandwidth parts.
20. The method of claim 19 , wherein the preamble and the random access channel resource is associated with the first uplink bandwidth part.