Power efficient discovery of LTE-direct relay for out-of-coverage devices

1. A method for managing wireless communications, comprising:

receiving, by an in-coverage mobile device, a peer discovery message from an out-of-coverage mobile device, the in-coverage mobile device being a mobile device within coverage of a base station, the out-of-coverage mobile device being a mobile device out of coverage or anticipated to be out of coverage of the base station, and the peer discovery message comprising an indication of a type of service or type of relay service required by the out-of-coverage mobile device;

determining, by the in-coverage mobile device in response to the peer discovery message, to transition to a relay status, the relay status indicating a capability of the in-coverage mobile device to function as a relay device between the base station in communication with the in-coverage mobile device and the out-of-coverage mobile device;

and

transmitting, by the in-coverage mobile device, a relay capability signal to the out-of-coverage mobile device based at least in part on the peer discovery message from the out-of-coverage mobile device and the transition to relay status, the relay capability signal indicating the relay status of the in-coverage mobile device.

2. The method of claim 1 , further comprising:

determining that an available operating power of the in-coverage mobile device exceeds a threshold; and

determining to transition to the relay status based at least in part on the determining that the available operating power of the in-coverage mobile device exceeds the threshold.

3. The method of claim 1 , further comprising:

determining that an available transmission bandwidth of the in-coverage mobile device exceeds a threshold; and

determining to transition to the relay status based at least in part on the determining that the available transmission bandwidth of the in-coverage mobile device exceeds the threshold.

4. The method of claim 1 , further comprising:

establishing a direct link with the out-of-coverage mobile device.

5. The method of claim 1 , further comprising:

determining, by the in-coverage mobile device, that the type of service required by the out-of-coverage mobile device is provided by the base station or that the type of relay service is supported by the in-coverage mobile device; and

establishing a direct link with the out-of-coverage mobile device based at least in part on the determining that the type of service required by the out-of-coverage mobile device is provided by the base station or that the type of relay service is supported by the in-coverage mobile device.

6. The method of claim 1 , further comprising:

receiving a transmission from the base station; and

retransmitting the transmission to the out-of-coverage mobile device.

7. The method of claim 1 , further comprising:

receiving a transmission from the out-of-coverage mobile device; and

retransmitting the transmission to the base station.

8. The method of claim 1 , further comprising:

receiving data from the base station; and

retransmitting the data to the out-of-coverage mobile device.

9. The method of claim 1 , further comprising:

determining that the in-coverage mobile device is in a coverage area of the base station; and

communicating, by the in-coverage mobile device, directly with the base station.

10. The method of claim 1 , further comprising:

determining that the out-of-coverage mobile device is out of coverage from the base station; and

communicating, by the in-coverage mobile device, with the out-of-coverage mobile device such that the out-of-coverage mobile device indirectly communicates with the base station.

11. A mobile device for managing wireless communications, the mobile device in coverage of a base station and comprising:

mean for receiving a peer discovery message from an out-of-coverage mobile device, the out-of-coverage mobile device being a mobile device out of coverage or anticipated to be out of coverage of the base station and the peer discovery message comprising an indication of a type of service or type of relay service required by the out-of-coverage mobile device;

means for determining to transition to a relay status in response to the peer discovery message, the relay status indicating a capability of the in-coverage mobile device to function as a relay device between the base station in communication with the in-coverage mobile device and the out-of-coverage mobile device; and

means for transmitting a relay capability signal to the out-of-coverage mobile device based at least in part on the peer discovery message from the out-of-coverage mobile device and the transition to relay status, the relay capability signal indicating the relay status of the in-coverage mobile device.

12. The in-coverage mobile device of claim 11 , further comprising:

means for determining that an available operating power of the in-coverage mobile device exceeds a threshold; and

means for determining to transition to the relay status based at least in part on the determining that the available operating power of the in-coverage mobile device exceeds the threshold.

13. The in-coverage mobile device of claim 11 , further comprising:

means for determining that an available transmission bandwidth of the in-coverage mobile device exceeds a threshold; and

means for determining to transition to the relay status based at least in part on the determining that the available transmission bandwidth of the in-coverage mobile device exceeds the threshold.

14. The in-coverage mobile device of claim 11 , further comprising:

means for establishing a direct link with the out-of-coverage mobile device.

15. The in-coverage mobile device of claim 11 , further comprising:

means for determining, by the in-coverage mobile device, that the type of service required by the out-of-coverage mobile device is provided by the base station or that the type of relay service is supported by the in-coverage mobile device; and

means for establishing a direct link with the out-of-coverage mobile device based at least in part on the determining that the type of service required by the out-of-coverage mobile device is provided by the base station or that the type of relay service is supported by the in-coverage mobile device.

16. The in-coverage mobile device of claim 11 , further comprising:

means for receiving a transmission from the base station; and

means for retransmitting the transmission to the out-of-coverage mobile device.

17. The in-coverage mobile device of claim 11 , further comprising:

means for receiving a transmission from the out-of-coverage mobile device; and

means for retransmitting the transmission to the base station.

18. The in-coverage mobile device of claim 11 , further comprising:

means for receiving data from the base station; and

means for retransmitting the data to the out-of-coverage mobile device.

19. The in-coverage mobile device of claim 11 , further comprising:

means for determining that the in-coverage mobile device is in a coverage area of the base station; and

means for communicating, by the in-coverage mobile device, directly with the base station.

20. The in-coverage mobile device of claim 11 , further comprising:

means for determining that the out-of-coverage mobile device is out of coverage from the base station; and

means for communicating with the out-of-coverage mobile device such that the out-of-coverage mobile device indirectly communicates with the base station.

21. A mobile device for managing wireless communications, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory, the instructions being executable by the processor to:

receive, while in coverage of a base station, a peer discovery message from an out-of-coverage mobile device, the out-of-coverage mobile device being a mobile device out of coverage or anticipated to be out of coverage of the base station and the peer discovery message comprising an indication of a type of service or type of relay service required by the out-of-coverage mobile device;

determine to transition to a relay status in response to the peer discovery message, the relay status indicating a capability of the in-coverage mobile device to function as a relay device between the base station in communication with the in-coverage mobile device and the out-of-coverage mobile device;

and

transmit a relay capability signal to the out-of-coverage mobile device based at least in part on the peer discovery message from the out-of-coverage mobile device and the transition to relay status, the relay capability signal indicating the relay status of the in-coverage mobile device.

22. The in-coverage mobile device of claim 21 , wherein the instructions are executable by the processor to:

determine that an available operating power of the in-coverage mobile device exceeds a threshold; and

determine to transition to the relay status based at least in part on the determining that the available operating power of the in-coverage mobile device exceeds the threshold.

23. The in-coverage mobile device of claim 21 , wherein the instructions are executable by the processor to:

determine that an available transmission bandwidth of the in-coverage mobile device exceeds a threshold; and

determine to transition to the relay status based at least in part on the determining that the available transmission bandwidth of the in-coverage mobile device exceeds the threshold.

24. The in-coverage mobile device of claim 21 , wherein the instructions are executable by the processor to:

establish a direct link with the out-of-coverage mobile device.

25. The in-coverage mobile device of claim 21 , wherein the instructions are executable by the processor to:

determine that the type of service required by the out-of-coverage mobile device is provided by the base station or that the type of relay service is supported by the in-coverage mobile device; and

establish a direct link with the out-of-coverage mobile device based at least in part on the determining that the type of service required by the out-of-coverage mobile device is provided by the base station or that the type of relay service is supported by the in-coverage mobile device.

26. The in-coverage mobile device of claim 21 , wherein the instructions are executable by the processor to:

receive data from the base station; and

retransmit the data to the out-of-coverage mobile device.

27. The in-coverage mobile device of claim 21 , wherein the instructions are executable by the processor to:

determine that the in-coverage mobile device is in a coverage area of the base station; and

communicate directly with the base station.

28. The in-coverage mobile device of claim 21 , wherein the instructions are executable by the processor to:

determine that the out-of-coverage mobile device is out of coverage from the base station; and

communicate with the out-of-coverage mobile device such that the out-of-coverage mobile device indirectly communicates with the base station.

29. A computer program product for managing wireless communications, the computer program product comprising a non-transitory computer-readable medium storing instructions executable by a processor to:

receive, by a mobile device in coverage of a base station, a peer discovery message from an out-of-coverage mobile device, the out-of-coverage mobile device being a mobile device out of coverage or anticipated to be out of coverage of the base station and the peer discovery message comprising an indication of a type of service or type of relay service required by the out-of-coverage mobile device;

determine, by the in-coverage mobile device in response to the peer discovery message, to transition to a relay status, the relay status indicating a capability of the in-coverage mobile device to function as a relay device between the base station in communication with the in-coverage mobile device and the out-of-coverage mobile device;

and

transmit, by the in-coverage mobile device, a relay capability signal to the out-of-coverage mobile device based at least in part on the peer discovery message from the out-of-coverage mobile device and the transition to relay status, the relay capability signal indicating the relay status of the in-coverage mobile device.

30. The computer program product of claim 29 , wherein the instructions are executable by the processor to:

determine that an available operating power of the in-coverage mobile device exceeds a threshold; and

determine to transition to the relay status based at least in part on the determining that the available operating power of the in-coverage mobile device exceeds the threshold.

31. The computer program product of claim 29 , wherein the instructions are executable by the processor to:

determine that an available transmission bandwidth of the in-coverage mobile device exceeds a threshold; and

determine to transition to the relay status based at least in part on the determining that the available transmission bandwidth of the in-coverage mobile device exceeds the threshold.

32. The computer program product of claim 29 , wherein the instructions are executable by the processor to:

establish a direct link with the out-of-coverage mobile device.

33. The computer program product of claim 29 , wherein the instructions are executable by the processor to:

determine that the out-of-coverage mobile device is out of coverage from the base station; and

communicate with the out-of-coverage mobile device such that the out-of-coverage mobile device indirectly communicates with the base station.

34. A method for managing wireless communications, comprising:

transmitting, by an out-of-coverage mobile device, a peer discovery message comprising an indication of a type of service or type of relay service required by the out-of-coverage mobile device, wherein the out-of-coverage mobile device is out of coverage or anticipates a transition to being out of coverage with respect to a base station;

receiving, by the out-of-coverage mobile device in response to the peer discovery message, a relay capability message from a mobile device in coverage of the base station, the relay capability message comprising a relay status indicating a capability of the in-coverage mobile device to function as a relay device between the out-of-coverage mobile device and the base station; and

determining whether to use the in-coverage mobile device as a relay device for communication between the out-of-coverage mobile device and the base station based on the relay capability message.

35. The method of claim 34 , wherein the determination is based on a remaining battery life of the in-coverage mobile device.

36. The method of claim 34 , wherein the peer discovery message is a broadcast signal and the relay capability message is a unicast signal.

37. An apparatus for managing wireless communications at a mobile device, comprising:

means for transmitting a peer discovery message comprising an indication of a type of service or type of relay service required by the mobile device in an out-of-coverage state, wherein the out-of-coverage state corresponds to the mobile device being out-of-coverage or anticipating a transition to being out-of-coverage with respect to a base station;

means for receiving, in response to the peer discovery message, a relay capability message from a mobile device in coverage of the base station, the relay capability message comprising a relay status indicating a capability of the in-coverage mobile device to function as a relay device between the out-of-coverage mobile device and the base station; and

means for determining whether to use the in-coverage mobile device as a relay device for communication between the out-of-coverage mobile device and the base station based on the relay capability message.

38. The out-of-coverage mobile device of claim 37 , wherein the determination is based on a remaining battery life of the in-coverage mobile device.

39. The out-of-coverage mobile device of claim 37 , wherein the peer discovery message is a broadcast signal and the relay capability message is a unicast signal.

40. An apparatus for managing wireless communications at a mobile device, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory, the instructions being executable by the processor to:

transmit a peer discovery message comprising an indication of a type of service or type of relay service required by the mobile device while in an out-of-coverage state, wherein the out-of-coverage mobile device is out-of-coverage or anticipates a transition to being out-of-coverage with respect to a base station;

receive, by the out-of-coverage mobile device in response to the peer discovery message, a relay capability message from a mobile device in coverage of the base station, the relay capability message comprising a relay status indicating a capability of the in-coverage mobile device to function as a relay device between the out-of-coverage mobile device and the base station; and

determine whether to use the in-coverage mobile device as a relay device for communication between the out-of-coverage mobile device and the base station based on the relay capability message.

41. The out-of-coverage mobile device of claim 40 , wherein the determination is based on a remaining battery life of the in-coverage mobile device.

42. The out-of-coverage mobile device of claim 40 , wherein the peer discovery message is a broadcast signal and the relay capability message is a unicast signal.

43. A computer program product for managing wireless communications at a mobile device, the computer program product comprising a non-transitory computer-readable medium storing instructions executable by a processor to:

transmit a peer discovery message comprising an indication of a type of service or type of relay service required by the mobile device while in an out-of-coverage state, wherein the out-of-coverage state corresponds to the mobile device being out-of-coverage or anticipating a transition to being out-of-coverage with respect to a base station;

receive, by the out-of-coverage mobile device in response to the peer discovery message, a relay capability message from a mobile device in coverage of the base station, the relay capability message comprising a relay status indicating a capability of the in-coverage mobile device to function as a relay device between the out-of-coverage mobile device and the base station in communication with the in-coverage mobile device; and

determine whether to use the in-coverage mobile device as a relay device for communication between the out-of-coverage mobile device and the base station based on the relay capability message.

44. The computer program product of claim 43 , wherein the determination is based on a remaining battery life of the in-coverage mobile device.

45. The computer program product of claim 43 , wherein the peer discovery message is a broadcast signal and the relay capability message is a unicast signal.