Power saving for paging

1. A method comprising:

receiving, by a wireless device, system information indicating:

a first number of paging sub-groups; and

a time offset associated with a paging early indication (PEI) occasion;

determining that the wireless device is associated with a first paging sub-group based on the first number and a wireless device identifier;

determining a time location of the PEI occasion based on the time offset;

receiving, based on monitoring a control channel in the PEI occasion, a downlink control information indicating one or more paging sub-groups for a paging occasion;

monitoring a control channel in the paging occasion in response to the one or more paging sub-groups comprising the first paging sub-group; and

receiving paging information.

2. The method of claim 1 , wherein the receiving the system information is via a system information block 1 (SIB 1 ) message.

3. The method of claim 1 , further comprising determining the paging occasion based on the wireless device identifier.

4. The method of claim 3 , wherein:

the system information further indicates:

a second number of paging frames in a discontinuous reception (DRX) cycle; and

a third number of paging occasions for a paging frame; and

the determining the paging occasion is further based on the second number and the third number.

5. The method of claim 4 , wherein the determining that the wireless device is associated with the first paging sub-group is further based on the second number and the third number.

6. The method of claim 1 , wherein the time location of the PEI occasion is prior to a timing of the paging occasion.

7. The method of claim 1 , wherein the downlink control information comprises a field with a value indicating the first paging sub-group for the paging occasion.

8. The method of claim 1 , wherein a radio network temporary identifier (RNTI), associated with the downlink control information, is associated with paging early indication.

9. The method of claim 1 , wherein the monitoring the control channel in the paging occasion is for a paging RNTI.

10. The method of claim 1 , wherein the receiving the downlink control information is based on a search space associated with paging early indication.

11. 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 system information indicating:

a first number of paging sub-groups; and

a time offset associated with a paging early indication (PEI) occasion;

determine that the wireless device is associated with a first paging sub-group based on the first number and a wireless device identifier;

determine a time location of the PEI occasion based on the time offset;

receive, based on monitoring a control channel in the PEI occasion, a downlink control information indicating one or more paging sub-groups for a paging occasion;

monitor a control channel in the paging occasion in response to the one or more paging sub-groups comprising the first paging sub-group; and

receive paging information.

12. The wireless device of claim 11 , wherein receiving the system information is via a system information block 1 (SIB 1 ) message.

13. The wireless device of claim 11 , wherein the instructions, when executed by the one or more processors, further cause the wireless device to determine the paging occasion based on the wireless device identifier.

14. The wireless device of claim 13 , wherein:

the system information further indicates:

a second number of paging frames in a discontinuous reception (DRX) cycle; and

a third number of paging occasions for a paging frame; and

determining the paging occasion is further based on the second number and the third number.

15. The wireless device of claim 14 , wherein the determining that the wireless device is associated with the first paging sub-group is further based on the second number and the third number.

16. The wireless device of claim 11 , wherein the time location of the PEI occasion is prior to a timing of the paging occasion.

17. The wireless device of claim 11 , wherein the downlink control information comprises a field with a value indicating the first paging sub-group for the paging occasion.

18. The wireless device of claim 11 , wherein a radio network temporary identifier (RNTI), associated with the downlink control information, is associated with paging early indication.

19. The wireless device of claim 1 , wherein receiving the downlink control information is based on a search space associated with paging early indication.

20. A system comprising:

a base station; and

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, from the base station, system information indicating: a first number of paging sub-groups; and a time offset associated with a paging early indication (PEI) occasion; determine that the wireless device is associated with a first paging sub-group based on the first number and a wireless device identifier; determine a time location of the PEI occasion based on the time offset; receive, based on monitoring a control channel in the PEI occasion, a downlink control information indicating one or more paging sub-groups for a paging occasion; monitor a control channel in the paging occasion in response to the one or more paging sub-groups comprising the first paging sub-group; and receive paging information.