Carrier activation in a multi-carrier wireless network

1. A method comprising:

transmitting at least one first message indicating that a wireless device supports configuration of a plurality of licensed cells and a plurality of licensed assisted access (LAA) cells;

receiving, in a first subframe, a media-access-control control element (MAC CE) comprising at least one parameter instructing the wireless device to activate at least one licensed cell and at least one LAA cell;

initiating channel monitoring on the at least one LAA cell before a first maximum number of subframes after the first subframe; and

initiating channel monitoring on the at least one licensed cell after the initiating channel monitoring on the at least one LAA cell and before a second maximum number of subframes after the first subframe, wherein the first maximum number of subframes is different than the second maximum number of subframes.

2. The method of claim 1 , further comprising receiving at least one second message comprising configuration parameters of a plurality of cells that comprise the at least one licensed cell and the at least one LAA cell.

3. The method of claim 2 , wherein the configuration parameters comprise a deactivation timer.

4. The method of claim 1 , further comprising starting transmission of first valid channel state information (CSI) reports for the at least one LAA cell before the first maximum number of subframes after the first subframe.

5. The method of claim 4 , further comprising starting transmission of first out of range (OOR) CSI reports for the at least one LAA cell before the first valid CSI reports are available.

6. The method of claim 4 , wherein the starting transmission of the first valid CSI reports starts a first number of subframes after the first subframe.

7. The method of claim 1 , wherein the performing channel monitoring on the at least one LAA cell starts a first number of subframes after the first subframe.

8. The method of claim 1 , wherein an activation delay of a cell depends on whether the cell is licensed or LAA.

9. The method of claim 1 , wherein channel monitoring comprises a monitoring a physical downlink control channel.

10. A method comprising:

transmitting at least one first message indicating that a wireless device supports configuration of a plurality of licensed cells and a plurality of licensed assisted access (LAA) cells;

receiving, in a first subframe, a media-access-control control element (MAC CE) comprising at least one first parameter instructing the wireless device to activate at least one licensed cell;

receiving, in a second subframe, a second MAC CE comprising at least one second parameter instructing the wireless device to activate at least one LAA cell;

initiating channel monitoring on the at least one LAA cell before a first maximum number of subframes after the first subframe; and

initiating channel monitoring on the at least one licensed cell after the initiating channel monitoring on the at least one LAA cell and before a second maximum number of subframes after the second subframe, wherein the first maximum number of subframes is different than the second maximum number of subframes.

11. The method of claim 10 , further comprising receiving at least one second message comprising configuration parameters of a plurality of cells that comprise the at least one licensed cell and the at least one LAA.

12. The method of claim 11 , further comprising starting transmission of first valid channel state information (CSI) reports for the at least one LAA cell before the first maximum number of subframes after the first subframe.

13. The method of claim 12 , wherein the starting transmission of first valid CSI reports starts a first number of subframes after the first subframe.

14. The method of claim 10 , further comprising starting transmission of second valid CSI reports for the at least one licensed cell before the second maximum number of subframes after the second subframe.

15. The method of claim 14 , wherein the starting transmission of second valid CSI reports for the at least one LAA cell starts a first number of subframes after the second subframe.

16. The method of claim 10 , wherein the performing channel monitoring on the at least one LAA cell starts a first number of subframes after the first subframe.

17. The method of claim 10 , wherein the performing channel monitoring on the at least one licensed cell starts a first number of subframes after the second subframe.

18. A wireless device comprising:

one or more processors; and

memory storing instructions that, when executed, cause the wireless device to:

transmit at least one first message indicating that the wireless device supports configuration of a plurality of licensed cells and a plurality of licensed assisted access (LAA) cells;

receive, in a first subframe, a media-access-control control element (MAC CE) comprising at least one first parameter instructing the wireless device to activate at least one licensed cell;

receive, in a second subframe, a second MAC CE comprising at least one second parameter to activate at least one LAA cell;

initiate channel monitoring on the at least one LAA cell before a first maximum number of subframes after the first subframe; and

initiate channel monitoring on the at least one licensed cell after the initiating channel monitoring on the at least one LAA cell and before a second maximum number of subframes after the second subframe, wherein the first maximum number of subframes is different than the second maximum number of subframes.