Autonomous discovery for enhanced wifi devices

• US 8,867,512 B2
• Filed: 07/30/2012
• Issued: 10/21/2014
• Est. Priority Date: 07/30/2012
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Li, Junyi, Sampath, Hemanth, Tavildar, Saurabha Rangrao
• Primary Examiner(s): Lai, Andrew
• Assistant Examiner(s): Ganguly, Sumitra
• Application Number:
  US13/562,167
• Publication Number:
  US 20140029596A1
• Time in Patent Office: 813 Days
• Field of Search: 370/338, 370/328, 370/229, 709/227, 709/228
• US Class Current: 370/338
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals

Abstract

Techniques for discovering one or more nodes in a communication system are provided. A node may receive one or more discovery messages during a first occurrence of a periodic discovery interval. The node may determine a duration of a subsequent occurrence of the periodic discovery interval based on the one or more received discovery messages. The node may adjust the duration for the subsequent occurrence of the periodic discovery interval based on the determined duration.

Claims

1. A discovery method for wireless communication comprising:

operating, by a processor, a first node to receive one or more discovery messages from one or more other nodes during a first occurrence of a periodic discovery interval;

operating, by a processor, the first node to determine a duration of a subsequent occurrence of the periodic discovery interval based on the one or more received discovery messages, said discovery interval including a first time during which said first node listens for discovery messages and a second time during which said first node transmits a discovery message, said determined duration being a time less than or equal to N, wherein N is an initial discovery interval length assigned by an access point; and

operating, by a processor, the first node to adjust the duration of the subsequent occurrence of the periodic discovery interval based on the determined duration and to reduce a range of count down times used to determine a random starting position of a discovery transmission when the adjusted duration of the subsequent occurrence of the periodic discovery interval is less than N.

2. The method of claim 1, wherein the determining of the duration is based on a count of the one or more received discovery messages;

and wherein the determining of the duration comprises comparing the count to a threshold.

3. The method of claim 1, further comprising:

proceeding with a transmission of data upon the expiration of a periodic discovery interval having a duration less than N without waiting for the expiration of the time period N.

4. The method of claim 1, further comprising operating the first node to transmit a discovery message comprising the determined duration to other nodes during the subsequent occurrence of the periodic discovery interval at a randomly determined time within the subsequent occurrence of the periodic discovery interval.

5. The method of claim 1, wherein the first node receives each of the discovery messages from different nodes relative to one another and each of the discovery messages comprises a count of a number of discovery messages received during an occurrence of the periodic discovery interval by the node from which the discovery message was received.

6. The method of claim 5, wherein the determining of the duration is based on the counts of the discovery messages.

7. The method of claim 6, wherein the determining of the duration is based on the largest of the counts of the discovery messages.

8. The method of claim 6, wherein the determining of the duration comprises comparing the counts of the discovery messages to a threshold.

9. The method of claim 1, wherein the adjusting of the duration comprises reducing the duration of the subsequent occurrence of the periodic discovery interval relative to the first occurrence of the periodic discovery interval.

10. The method of claim 1, wherein the first node which supports adjusting the duration of the subsequent occurrence of the periodic discovery interval is given communication priority over nodes which do not support adjusting the duration of the subsequent occurrence of the periodic discovery interval.

11. The method of claim 1, further comprising disabling a receiver of the first node between the occurrences of the periodic discovery interval.

12. The method of claim 1, further comprising:

prior to the subsequent occurrence of the periodic discovery interval, operating the first node to begin transmission of data to another node,

operating the first node to interrupt the transmission of the data during the subsequent occurrence of the periodic discovery interval, and

operating the first node to resume the transmission of the data after the subsequent occurrence of the periodic discovery interval.

13. A first node configured to discover one or more other nodes in a wireless communication system, comprising:

a receiver configured to receive one or more discovery messages from one or more other nodes during a first occurrence of a periodic discovery interval;

a sensing module configured to determine a duration of a subsequent occurrence of the periodic discovery interval based on the one or more received discovery messages, said discovery interval including a first time during which said first node listens for discovery messages and a second time during which said first node transmits a discovery message, said determined duration being a time less than or equal to N, wherein N is an initial discovery interval length assigned by an access point; and

a discovery module configured to adjust the duration of the subsequent occurrence of the periodic discovery interval based on the determined duration and to reduce a range of count down times used to determine a random starting position of a discovery transmission when the adjusted duration of the subsequent occurrence of the periodic discovery interval is less than N.

14. The first node of claim 13, wherein the sensing module is further configured to determine the duration based on a count of the one or more received discovery messages and by comparing the count to a threshold.

15. The first node of claim 13, further comprising a transmitter configured to transmit a discovery message comprising the determined duration to one or more other nodes during the subsequent occurrence of the periodic discovery interval.

16. The first node of claim 15, wherein the transmitter is further configured to transmit the discovery message at a randomly determined time within the subsequent occurrence of the periodic discovery interval.

17. The first node of claim 13, wherein the receiver is further configured to receive each of the discovery messages from different nodes relative to one another and each of the discovery messages comprises a count of a number of discovery messages received during an occurrence of the periodic discovery interval by the node from which the discovery message was received.

18. The first node of claim 17, wherein the sensing module is further configured to determine the duration based on the counts of the discovery messages.

19. The first node of claim 18, wherein the sensing module is further configured to determine the duration based on the largest of the counts of the discovery messages.

20. The first node of claim 18, wherein the sensing module is further configured to determine the duration by comparing the counts of the discovery messages to a threshold.

21. The first node of claim 13, wherein the discovery module is further configured to adjust the duration by reducing the duration of the subsequent occurrence of the periodic discovery interval relative to the first occurrence of the periodic discovery interval.

22. The first node of claim 13, wherein the first node which supports adjusting the duration of the subsequent occurrence of the periodic discovery interval is given communication priority over nodes which do not support adjusting the duration of the subsequent occurrence of the periodic discovery interval.

23. The first node of claim 13, wherein the receiver is further configured to power down between the occurrences of the periodic discovery interval.

24. The first node of claim 13,

wherein said discovery module is further configured to interrupt the transmission of the data during the subsequent occurrence of the periodic discovery interval;

and

wherein the first node further comprises a transmitter configured to;

begin transmission, prior to the subsequent occurrence of the periodic discovery interval, of data to another node; and

resume the transmission after the interruption of the transmission of the data during the subsequent occurrence of the periodic discovery interval.

25. A computer program product, comprising:

a non-transitory computer-readable medium associated with a first node configured to discover one or more other nodes in a communication system, comprising;

code for receiving one or more discovery messages from one or more other nodes during a first occurrence of a periodic discovery interval;

code for determining a duration of a subsequent occurrence of the periodic discover discovery interval based on the one or more received discovery messages, said discovery interval including a first time during which said first node listens for discovery messages and a second time during which said first node transmits a discovery message, said determined duration being a time less than or equal to N, wherein N is an initial discovery interval length assigned by an access point; and

code for adjusting the duration of the subsequent occurrence of the periodic discovery interval based on the determined duration and reducing a range of count down times used to determine a random starting position of a discovery transmission when the adjusted duration of the subsequent occurrence of the periodic discovery interval is less than N.

26. The computer program product of claim 25, wherein the code for determining the duration comprises code for determining the duration based on a count of the one or more received discovery messages and based on comparing the count to a threshold.

27. The computer program product of claim 25, further comprising code for transmitting a discovery message comprising the determined duration to other nodes during the subsequent occurrence of the periodic discovery interval.

28. The computer program product of claim 27, wherein the code for transmitting the discovery message comprises code for transmitting the discovery message at a randomly determined time within the subsequent occurrence of the periodic discovery interval.

29. The computer program product of claim 25, wherein the first node receives each of the discovery messages from the one or more other nodes relative to one another and each of the discovery messages comprises a count of a number of discovery messages received during an occurrence of the periodic discovery interval by the node from which the discovery message was received.

30. The computer program product of claim 29, wherein the code for determining the duration is based on the counts of the discovery messages.

31. The computer program product of claim 30, wherein the determining the duration is based on the largest of the counts of the discovery messages.

32. The computer program product of claim 30, wherein the determining the duration comprises comparing the counts of the discovery messages to a threshold.

33. The computer program product of claim 25, wherein the adjusting the duration comprises reducing the duration of the subsequent occurrence of the periodic discovery interval relative to the first occurrence of the periodic discovery interval.

34. The computer program product of claim 25, wherein the first node which supports adjusting the duration of the subsequent occurrence of the periodic discovery interval is given communication priority over nodes which do not support adjusting the duration of the subsequent occurrence of the periodic discovery interval.

35. The computer program product of claim 25, further comprising code for disabling a receiver of the first node between the occurrences of the periodic discovery interval.

36. The computer program product of claim 25, further comprising:

code for beginning transmission of data to another node, prior to the subsequent occurrence of the periodic discovery interval,

code for interrupting the transmission of the data during the subsequent occurrence of the periodic discovery interval, and

code for resuming the transmission.