Downlink and uplink channel transmission and monitoring in a wireless network

1. A method comprising:

receiving, by a wireless device, one or more radio resource control (RRC) messages comprising configuration parameters for a first unlicensed cell and a second unlicensed cell;

receiving a downlink transmission via the second unlicensed cell; and

based on the downlink transmission via the second unlicensed cell, selectively monitoring a physical downlink control channel (PDCCH) during a time duration for the first unlicensed cell.

2. The method of claim 1 , wherein the downlink transmission is a physical downlink shared channel (PUSCH) transmission.

3. The method of claim 1 , wherein the PDCCH is an enhanced PDCCH.

4. The method of claim 1 , wherein the first unlicensed cell and the second unlicensed cell belong to a first cell group.

5. The method of claim 4 , wherein the first cell group comprises a plurality of cells that operate in a first frequency band.

6. The method of claim 4 , wherein the one or more RRC messages further comprise one or more configuration parameters of the first cell group.

7. The method of claim 1 , wherein the time duration is a subframe.

8. The method of claim 1 , wherein receiving the downlink transmission comprises receiving the downlink transmission during a partial uplink subframe.

9. The method of claim 1 , wherein receiving the downlink transmission comprises receiving the downlink transmission during a full uplink subframe.

10. The method of claim 1 , wherein the first unlicensed cell and the second unlicensed cell operate according to frame structure Type 3.

11. The method of claim 1 , further comprising:

based on a downlink transmission not occurring during a second time duration for the second unlicensed cell, monitoring the PDCCH during a time duration for the first unlicensed cell.

12. 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 radio resource control (RRC) messages comprising configuration parameters for a first unlicensed cell and a second unlicensed cell;

receive a downlink transmission via the second unlicensed cell; and

based on the downlink transmission via the second unlicensed cell, selectively monitor a physical downlink control channel (PDCCH) during a time duration for a first unlicensed cell.

13. The wireless device of claim 12 , wherein the downlink transmission is a physical downlink shared channel (PDSCH) transmission.

14. The wireless device of claim 12 , wherein the PDCCH is an enhanced PDCCH.

15. The wireless device of claim 12 , wherein the first unlicensed cell and the second unlicensed cell belong to a first cell group.

16. The wireless device of claim 15 , wherein the first cell group comprises a plurality of cells that operate in a first frequency band.

17. The wireless device of claim 15 , wherein the one or more RRC messages further comprise one or more configuration parameters of the first cell group.

18. The wireless device of claim 12 , wherein the time duration is a subframe.

19. The wireless device of claim 12 , wherein the instructions, when executed by the one or more processors, cause the wireless device to receive the downlink transmission during a partial uplink subframe.

20. The wireless device of claim 12 , wherein the instructions, when executed by the one or more processors, cause the wireless device to receive the downlink transmission during a full uplink subframe.

21. The wireless device of claim 12 , wherein the first unlicensed cell and the second unlicensed cell operate according to frame structure Type 3.

22. The wireless device of claim 12 , wherein the instructions, when executed by the one or more processors, further cause the wireless device to monitor, based on a downlink transmission not occurring during a second time duration for the second unlicensed cell, the PDCCH during the second time duration for the first unlicensed cell.

23. A system comprising:

a first device; and

a second device;

wherein the first device comprises:

one or more processors; and

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

transmit, to the second device, one or more radio resource control (RRC) messages comprising configuration parameters for a first unlicensed cell and a second unlicensed cell; and

wherein the second device comprises:

one or more processors; and

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

receive a downlink transmission via the second unlicensed cell; and

based on the downlink transmission via the second unlicensed cell, selectively monitor a physical downlink control channel (PDCCH) during a time duration for the first unlicensed cell.

24. The system of claim 23 , wherein the downlink transmission is a physical downlink shared channel (PDSCH) transmission.

25. The system of claim 23 , wherein the PDCCH is an enhanced PDCCH.

26. The system of claim 23 , wherein the first unlicensed cell and the second unlicensed cell belong to a first cell group.

27. The system of claim 26 , wherein the first cell group comprises a plurality of cells that operate in a first frequency band.

28. The system of claim 26 , wherein the one or more RRC messages further comprise one or more configuration parameters of the first cell group.

29. The system of claim 23 , wherein the time duration is a subframe.

30. The system of claim 23 , wherein the instructions, when executed by the one or more processors, cause the second device to receive the downlink transmission during a partial uplink subframe.

31. The system of claim 23 , wherein the instructions, when executed by the one or more processors, cause the second device to receive the downlink transmission during a full uplink subframe.

32. The system of claim 23 , wherein the first unlicensed cell and the second unlicensed cell operate according to frame structure Type 3.

33. The system of claim 23 , wherein the instructions, when executed by the one or more processors of the second device, cause the second device to monitor, based on a downlink transmission not occurring during a second time duration for the second unlicensed cell, the PDCCH during the second time duration for the first unlicensed cell.

34. A computer readable medium storing instructions that, when executed, cause a wireless device to:

receive one or more radio resource control (RRC) messages comprising configuration parameters for a first unlicensed cell and a second unlicensed cell;

receive a downlink transmission via the second unlicensed cell, selectively monitor a physical downlink control channel (PDCCH) during a time duration for a first unlicensed cell.

35. The computer readable medium of claim 34 , wherein the downlink transmission is a physical downlink shared channel (PDSCH) transmission.

36. The computer readable medium of claim 34 , wherein the PDCCH is an enhanced PDCCH.

37. The computer readable medium of claim 34 , wherein the first unlicensed cell and the second unlicensed cell belong to a first cell group.

38. The computer readable medium of claim 37 , wherein the first cell group comprises a plurality of cells that operate in a first frequency band.

39. The computer readable medium of claim 37 , wherein the one or more RRC messages further comprise one or more configuration parameters of the first cell group.

40. The computer readable medium of claim 34 , wherein the time duration is a subframe.

41. The computer readable medium of claim 34 , wherein the time duration for the second unlicensed cell is a partial uplink subframe.

42. The computer readable medium of claim 34 , wherein the time duration for the second unlicensed cell is a full uplink subframe.

43. The computer readable medium of claim 34 , wherein the first unlicensed cell and the second unlicensed cell operate according to frame structure Type 3.

44. The computer readable medium of claim 34 , wherein the instructions, when executed, further cause the wireless device to monitor, based on a downlink transmission not occurring during a second time duration for the second unlicensed cell, the PDCCH during the second time duration for the first unlicensed cell.

45. The method of claim 1 , wherein the selectively monitoring comprises:

monitoring the PDCCH based on a first condition; and

skipping monitoring of the PDCCH based on a second condition.

46. The method of claim 45 , wherein:

the first condition comprises no uplink transmission during the time duration; and

the second condition comprises an uplink transmission during the time duration.

47. The wireless device of claim 12 , wherein the instructions, when executed by the one or more processors, cause the wireless device to selectively monitor the PDCCH at least by:

monitoring the PDCCH based on a first condition; and

skipping monitoring of the PDCCH based on a second condition.

48. The wireless device of claim 47 , wherein:

the first condition comprises no uplink transmission during the time duration; and

the second condition comprises an uplink transmission during the time duration.

49. The system of claim 23 , wherein the instructions, when executed by the one or more processors, cause the second device to selectively monitor the PDCCH at least by:

monitoring the PDCCH based on a first condition; and

skipping monitoring of the PDCCH based on a second condition.

50. The system of claim 49 , wherein:

the first condition comprises no uplink transmission during the time duration; and

the second condition comprises an uplink transmission during the time duration.