DISTRIBUTED DEVICE-TO-DEVICE SYNCHRONIZATION

• US 20150341873A1
• Filed: 05/23/2014
• Published: 11/26/2015
• Est. Priority Date: 05/23/2014
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Abedini, Navid, Tavildar, Saurabha Rangrao, Li, Junyi, Park, Vincent Douglas, Khude, Nilesh Nilkanth, Henri, Sbastien
• Granted Patent: US 10,129,838 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04W 56/001 Synchronization between nodes
• CPC Class Codes: H04W 56/0015 one node acting as a reference for the others
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/04 Wireless resource allocation

Abstract

Methods, systems, and devices are described that provide for D2D synchronization. The methods, systems, and/or devices may include tools and techniques that provide for synchronizing a mobile device based on detection of a reliability alarm. A reliability alarm may be used between mobile devices, which is transmitted and/or received on specific D2D resources. Since the resources are reserved for the reliability alarm, a mobile device which was previously isolated from network synchronization will be able to receive the reliability alarm that a reliable synchronization signal is close when it moves within range of a reliable device. Once a reliability alarm is received the mobile device may free other resources to allow it to receive synchronization signals from the reliable devices. The mobile device may then synchronize with the network based on the received synchronization signals and transmit its own reliability alarm for subsequent isolated devices to use.

Claims

1. A method for wireless synchronization comprising:

receiving, at a mobile device, a reliability alarm on resources allocated for the reliability alarm; and

synchronizing with a network based at least in part on the reliability alarm.

2. The method of claim 1, wherein synchronizing with the network comprises:

receiving synchronization signals on synchronization resources wherein the synchronization resources are made available based at least in part on the reliability alarm; and

synchronizing with the network based at least in part on the synchronization signals.

3. The method of claim 1, wherein the reliability alarm comprises an analog signal comprising at least one of a time offset and a counter.

4. The method of claim 1, further comprising:

transmitting a reliability alarm on the resources allocated for the reliability alarm.

5. The method of claim 4, wherein transmitting the reliability alarm comprises:

transmitting the reliability alarm for a number of synchronization periods while the mobile device is not synchronized with the network.

6. The method of claim 5, wherein transmitting the reliability alarm comprises:

transmitting the reliability alarm based on a probability of transmission.

7. The method of claim 1, further comprising:

determining that the reliability alarm exceeds a threshold.

8. The method of claim 1, wherein the resources allocated for the reliability alarm comprise device-to-device (D2D) resources.

9. The method of claim 2, wherein the synchronization resources comprise at least some of the device-to-device (D2D) resources not reserved for the reliability alarm.

10. A device for wireless synchronization comprising:

means for receiving, at a mobile device, a reliability alarm on resources allocated for the reliability alarm; and

means for synchronizing with a network based at least in part on the reliability alarm.

11. The device of claim 10, wherein the means for synchronizing with the network comprise:

means for receiving synchronization signals on synchronization resources wherein the synchronization resources are made available based at least in part on the reliability alarm; and

means for synchronizing with the network based at least in part on the synchronization signals.

12. The device of claim 10, wherein the reliability alarm comprises an analog signal comprising at least one of a time offset and a counter.

13. The device of claim 10, further comprising:

means for transmitting a reliability alarm on the resources allocated for the reliability alarm.

14. The device of claim 13, wherein the means for transmitting the reliability alarm comprise:

means for transmitting the reliability alarm for a number of synchronization periods while the mobile device is not synchronized with the network.

15. The device of claim 14, wherein the means for transmitting the reliability alarm comprises:

means for transmitting the reliability alarm based on a probability of transmission.

16. The device of claim 10, further comprising:

means for determining that the reliability alarm exceeds a threshold.

17. The device of claim 10, wherein the resources allocated for the reliability alarm comprise device-to-device (D2D) resources.

18. The device of claim 11, wherein the synchronization resources comprise at least some of the device-to-device (D2D) resources not reserved for the reliability alarm.

19. A device for wireless synchronization 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, at a mobile device, a reliability alarm on resources allocated for the reliability alarm; and

synchronize with a network based at least in part on the reliability alarm.

20. The device of claim 19, wherein synchronizing with the network comprises:

receiving synchronization signals on synchronization resources wherein the synchronization resources are made available based at least in part on the reliability alarm; and

synchronizing with the network based at least in part on the synchronization signals.

21. The device of claim 19, wherein the reliability alarm comprises an analog signal comprising at least one of a time offset and a counter.

22. The device of claim 19, wherein the instructions are further executable by the processor to:

transmit a reliability alarm on the resources allocated for the reliability alarm.

23. The device of claim 22, wherein transmitting the reliability alarm comprises:

transmitting the reliability alarm for a number of synchronization periods while the mobile device is not synchronized with the network.

24. The device of claim 23, wherein transmitting the reliability alarm comprises:

transmitting the reliability alarm based on a probability of transmission.

25. The device of claim 19, wherein the instructions are further executable by the processor to:

determine that the reliability alarm exceeds a threshold.

26. The device of claim 19, wherein the resources allocated for the reliability alarm comprise device-to-device (D2D) resources.

27. The device of claim 20, wherein the synchronization resources comprise at least some of the device-to-device (D2D) resources not reserved for the reliability alarm.

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

receive, at a mobile device, a reliability alarm on resources allocated for the reliability alarm; and

synchronize with a network based at least in part on the reliability alarm.

29. The computer program product of claim 28, wherein synchronizing with the network comprises:

receiving synchronization signals on synchronization resources wherein the synchronization resources are made available based at least in part on the reliability alarm; and

synchronizing with the network based at least in part on the synchronization signals.

30. The computer program product of claim 28, wherein the instructions are further executable by the processor to:

transmit a reliability alarm on the resources allocated for the reliability alarm.