LIMITING WIRELESS DISCOVERY RANGE

• US 20130250931A1
• Filed: 02/08/2013
• Published: 09/26/2013
• Est. Priority Date: 03/13/2012
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Abraham, Santosh Paul, Cherian, George, Sampath, Hemanth, Merlin, Simone, De Vegt, Rolf
• Granted Patent: US 9,510,292 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04W 28/021 in wireless networks with changing topologies, e.g. ad-hoc networks self-organizing networks H04W84/18
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 52/04 TPC
• CPC Class Codes: H04W 64/006 with additional information processing, e.g. for direction or speed determination
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

Systems and methods of limiting wireless discovery range are described. A transmitting device may limit wireless discovery range by adjusting one or more transmission attributes of a discovery message, measuring inter-device distance based on range determination messages, or any combination thereof. A receiving device may limit wireless discovery range based on one or more attributes of a received discovery message, measuring inter-device distance based on range determination messages, or any combination thereof. Discovery messages may include a range adaptation bit indicating whether range adaptation is to be performed.

Claims

1. A method comprising:

adjusting a transmission attribute at a first device based on a discovery range threshold such that in response to sending a discovery message from the first device in accordance with the adjusted transmission attribute, a second device at a distance within the discovery range threshold decodes the discovery message and a third device at a distance outside the discovery range threshold discards the discovery message.

2. The method of claim 1, wherein the transmission attribute includes a transmit power level, a modulation and coding scheme (MCS), or any combination thereof.

3. A method comprising:

determining, at a first device, a discovery range threshold that limits a distance from the first device at which a second device is operative to decode a discovery message;

adjusting a transmission attribute at the first device based on the discovery range threshold; and

sending the discovery message in accordance with the adjusted transmission attribute.

4. The method of claim 3, wherein the transmission attribute includes a transmit power level, a modulation and coding scheme (MCS), or any combination thereof.

5. The method of claim 3, wherein the discovery message is included in an information element of an Institute of Electrical and Electronics Engineers (IEEE) 802.11 beacon.

6. The method of claim 3, wherein the discovery message is included in a management action frame.

7. The method of claim 3, further comprising encoding information to be displayed by the second device into the discovery message.

8. The method of claim 3, further comprising encoding a uniform resource locator (URL) to be navigated to by the second device into the discovery message.

9. The method of claim 3, wherein the first device comprises a wireless local area network (WLAN) device, an access point, or any combination thereof.

10. The method of claim 3, further comprising determining the discovery range threshold at the first device.

11. The method of claim 3, further comprising receiving data indicating the discovery range threshold from a device other than the first device.

12. An apparatus comprising:

a processor; and

a memory storing instructions executable by the processor to adjust a transmission attribute at a first device based on a discovery range threshold such that in response to sending a discovery message from the first device in accordance with the adjusted transmission attribute, a second device at a distance within the discovery range threshold decodes the discovery message and a third device at a distance outside the discovery range threshold discards the discovery message.

13. A non-transitory processor-readable medium comprising instructions that, when executed by a processor, cause the processor to:

adjust a transmission attribute at a first device based on a discovery range threshold such that in response to sending a discovery message from the first device in accordance with the adjusted transmission attribute, a second device at a distance within the discovery range threshold decodes the discovery message and a third device at a distance outside the discovery range threshold discards the discovery message.

14. An apparatus comprising:

means for determining, at a first device, a discovery range threshold that limits a distance from the first device at which a second device is operative to decode a discovery message;

means for adjusting a transmission attribute at the first device based on the discovery range threshold; and

means for sending the discovery message in accordance with the adjusted transmission attribute.

15. A method comprising:

receiving at a second device a discovery message from a first device;

determining a distance between the second device and the first device based on at least one attribute of the discovery message;

when the distance is within a discovery range threshold, decoding the discovery message; and

when the distance is outside the discovery range threshold, discarding the discovery message.

16. The method of claim 15, wherein the at least one attribute of the discovery message includes a received signal strength indication (RSSI).

17. The method of claim 16, wherein determining the distance comprises searching a table that associates RSSI values with expected distances.

18. The method of claim 17, wherein the table is stored at the second device.

19. The method of claim 15, wherein the at least one attribute of the discovery message includes a transmit power, and wherein the discovery message includes an indicator of the transmit power.

20. The method of claim 15, wherein the at least one attribute of the discovery message includes a modulation and coding scheme (MCS).

21. The method of claim 15, wherein the discovery range threshold is included in the discovery message.

22. The method of claim 15, further comprising, when the distance is within the discovery range threshold, displaying at least a portion of the decoded discovery message at the second device.

23. The method of claim 15, further comprising, when the distance is within the discovery range threshold, navigating to a uniform resource locator (URL) in the decoded discovery message via an application executed at the second device.

24. The method of claim 15, wherein the second device comprises a mobile telephone, a portable computing device, a tablet computing device, a personal digital assistant (PDA), a portable media player, or any combination thereof.

25. An apparatus comprising:

a processor; and

a memory storing instructions executable by the processor to;

receive at a second device a discovery message from a first device;

determine a distance between the second device and the first device based on at least one attribute of the discovery message;

when the distance is within a discovery range threshold, decode the discovery message; and

when the distance is outside the discovery range threshold, discard the discovery message.

26. A non-transitory processor-readable medium comprising instructions that, when executed by a processor, cause the processor to:

receive at a second device a discovery message from a first device;

determine a distance between the second device and the first device based on at least one attribute of the discovery message;

when the distance is within a discovery range threshold, decode the discovery message; and

when the distance is outside the discovery range threshold, discard the discovery message.

27. An apparatus comprising:

means for receiving at a second device a discovery message from a first device;

means for determining a distance between the second device and the first device based on at least one attribute of the discovery message;

means for decoding the discovery message when the distance is within a discovery range threshold; and

means for discarding the discovery message when the distance is outside the discovery range threshold.

28. A method comprising:

sending a range determination message from a first device to a second device;

receiving a range determination response at the first device from the second device;

determining a distance between the first device and the second device based on an elapsed time between the sending of the range determination message and the receiving of the range determination response; and

in response to determining that the distance is within a discovery range threshold, sending a discovery message from the first device to the second device.

29. The method of claim 28, further comprising:

starting a timer at the first device upon sending the range determination message;

stopping the timer upon receiving the range determination response; and

determining the elapsed time based on the timer.

30. The method of claim 28, wherein the range determination message comprises a request-to-send (RTS) message and wherein the range determination response comprises a clear-to-send (CTS) message.

31. An apparatus comprising:

a processor; and

a memory storing instructions executable by the processor to;

send a range determination message from a first device to a second device;

receive a range determination response at the first device from the second device;

determine a distance between the first device and the second device based on an elapsed time between the sending of the range determination message and the receiving of the range determination response; and

in response to determining that the distance is within a discovery range threshold, send a discovery message from the first device to the second device.

32. A non-transitory processor-readable medium comprising instructions that, when executed by a processor, cause the processor to:

send a range determination message from a first device to a second device;

receive a range determination response at the first device from the second device;

determine a distance between the first device and the second device based on an elapsed time between the sending of the range determination message and the receiving of the range determination response; and

in response to determining that the distance is within a discovery range threshold, send a discovery message from the first device to the second device.

33. An apparatus comprising:

means for sending a range determination message from a first device to a second device;

means for receiving a range determination response at the first device from the second device;

means for determining a distance between the first device and the second device based on an elapsed time between the sending of the range determination message and the receiving of the range determination response; and

means for sending a discovery message from the first device to the second device in response to determining that the distance is within a discovery range threshold.

34. A method comprising:

sending a range determination message from a second device to a first device;

receiving a range determination response from the first device at the second device;

determining a distance between the second device and the first device based on an elapsed time between the sending of the range determination message and the receiving of the range determination response;

when the distance is within a discovery range threshold, decoding a discovery message received from the first device; and

when the distance is outside the discovery range threshold, discarding the discovery message received from the first device.

35. The method of claim 34, wherein the discovery message is received prior to sending the range determination message.

36. The method of claim 34, wherein the discovery message is received subsequent to receiving the range determination response.

37. An apparatus comprising:

a processor; and

a memory storing instructions executable by the processor to;

send a range determination message from a second device to a first device;

receive a range determination response from the first device at the second device;

determine a distance between the second device and the first device based on an elapsed time between the sending of the range determination message and the receiving of the range determination response;

when the distance is within a discovery range threshold, decode a discovery message received from the first device; and

when the distance is outside the discovery range threshold, discard the discovery message received from the first device.

38. A non-transitory processor-readable medium storing instructions that, when executed by a processor, cause the processor to:

send a range determination message from a second device to a first device;

receive a range determination response from the first device at the second device;

determine a distance between the second device and the first device based on an elapsed time between the sending of the range determination message and the receiving of the range determination response;

when the distance is within a discovery range threshold, decode a discovery message received from the first device; and

when the distance is outside the discovery range threshold, discard the discovery message received from the first device.

39. An apparatus comprising:

means for sending a range determination message from a second device to a first device;

means for receiving a range determination response from the first device at the second device;

means for determining a distance between the second device and the first device based on an elapsed time between the sending of the range determination message and the receiving of the range determination response;

means for decoding a discovery message received from the first device when the distance is within a discovery range threshold; and

means for discarding the discovery message received from the first device when the distance is outside the discovery range threshold.

40. A method comprising:

sending a discovery message from a first device to a second device,

wherein the discovery message includes data indicating whether a range determination mechanism is to be used to determine whether to perform an action in response to the discovery message.

41. The method of claim 40, wherein the discovery message includes a range adaptation bit that indicates whether the second device is to decode the discovery message from the first device independent of whether a distance between the first device and the second device is within a discovery range threshold.

42. The method of claim 40, wherein the discovery message further includes a discovery range threshold.

43. The method of claim 40, wherein the range determination mechanism is based on a received signal strength indication (RSSI) of the discovery message, a transmit power level of the discovery message, or any combination thereof.

44. The method of claim 40, wherein the range determination mechanism is based on a round trip time measurement.

45. The method of claim 40, wherein the discovery message is sent via a wireless network that is compliant with a first networking technology and wherein the range determination mechanism is based on a second networking technology that is different from the first networking technology.

46. The method of claim 45, wherein the range determination mechanism is based on a Bluetooth signal, a near field communication (NFC) signal, or any combination thereof.

47. The method of claim 40, wherein the range determination mechanism is based on a global positioning system (GPS) signal.

48. The method of claim 40, wherein the discovery message is sent from a first device to a second device, and wherein the range determination mechanism is based on at least one measurement with respect to a third device that is distinct from the first device and the second device.

49. The method of claim 48, wherein the third device comprises a wireless access point, a cellular tower, or any combination thereof.

50. The method of claim 40, wherein the discovery message includes at least one discovery type-length-value (TLV).

51. The method of claim 50, wherein the at least one discovery TLV includes a range control field.

52. The method of claim 51, wherein the range control field identifies the range determination mechanism.

53. The method of claim 40, wherein the discovery message comprises a peer-to-peer information element (P2P IE).

54. The method of claim 53, wherein the P2P IE includes a range control field.

55. The method of claim 54, wherein the range control field identifies the range determination mechanism.

56. An apparatus comprising:

a processor; and

a memory storing instructions executable by the processor to send a discovery message from a first device to a second device,

wherein the discovery message includes data indicating whether a range determination mechanism is to be used to determine whether to perform an action in response to the discovery message.

57. The apparatus of claim 56, wherein the action comprises initiating setup of a WiFi Direct connection between the first device and the second device.

58. A non-transitory processor-readable medium storing instructions that, when executed by a processor, cause the processor to:

send a discovery message from a first device to a second device,

wherein the discovery message includes data indicating whether a range determination mechanism is to be used to determine whether to perform an action in response to the discovery message.

59. An apparatus comprising:

means for determining a discovery range threshold at a first device; and

means for sending a discovery message from the first device to a second device,

wherein the discovery message includes data indicating whether a range determination mechanism is to be used to determine whether to perform an action in response to the discovery message.

60. A method comprising:

receiving a discovery message from a first device at a second device, wherein the discovery message includes a range adaptation indicator bit;

when the range adaptation bit has a first value, decoding the discovery message; and

when the range adaptation bit has a second value, selectively decoding or discarding the discovery message based on whether a distance between the second device and the first device is within a discovery range threshold included in the discovery message.

61. An apparatus comprising:

a processor; and

a memory storing instructions executable by the processor to;

receive a discovery message from a first device at a second device, wherein the discovery message includes a range adaptation indicator bit;

when the range adaptation bit has a first value, decode the discovery message; and

when the range adaptation bit has a second value, selectively decode or discard the discovery message based on whether a distance between the second device and the first device is within a discovery range threshold included in the discovery message.

62. A non-transitory processor-readable medium storing instructions that, when executed by a processor, cause the processor to:

receive a discovery message from a first device at a second device, wherein the discovery message includes a range adaptation indicator bit;

when the range adaptation bit has a first value, decode the discovery message; and

when the range adaptation bit has a second value, selectively decode or discard the discovery message based on whether a distance between the second device and the first device is within a discovery range threshold included in the discovery message.

63. An apparatus comprising:

means for receiving a discovery message from a first device at a second device, wherein the discovery message includes a range adaptation indicator bit;

means, responsive to the range adaptation bit having a first value, for decoding the discovery message; and

means, responsive to the range adaptation bit having a second value, for selectively decoding or discarding the discovery message based on whether a distance between the second device and the first device is within a discovery range threshold included in the discovery message.

64. A method comprising:

receiving a discovery message from a first device at a second device;

sending a request for a location of the first device;

receiving a response indicating the location of the first device;

determining a distance between the second device and the first device based on the location of the first device; and

selectively decoding or discarding the discovery message based on whether the distance is within a discovery range threshold.

65. The method of claim 64, wherein the request is sent to a location database and wherein the response is received from the location database.

66. The method of claim 64, wherein the request is sent to the first device and wherein the response is received from the first device.

67. The method of claim 64, wherein the location of the first device is determined using a global positioning system (GPS) transceiver of the first device.

68. The method of claim 64, wherein the distance between the second device and the first device is determined at a first time, and further comprising:

at a second time subsequent to the first time, determining whether the distance between the second device and the first device continues to be within the discovery range threshold.

69. A method comprising:

receiving a message from a first device at a second device, wherein the message comprises a discovery message or a query message;

executing a first range determination mechanism in response to determining that the message indicates that range determination is to be performed;

when a result of the first range determination mechanism indicates that the first device and the second device are separated by a distance that is greater than or equal to a first range threshold, discarding the received message; and

when the result of the first range determination mechanism indicates that the first device and the second device are separated by a distance that is less than the first range threshold;

executing a second range determination mechanism; and

selectively discarding the message or performing at least one action in response to the message based on a result of the second range determination mechanism.

70. The method of claim 69, wherein the first range determination mechanism is based on a received signal strength indication (RSSI) of the message, a transmit power level of the message, or any combination thereof, and wherein the second range determination mechanism is based on a round trip time measurement.

71. The method of claim 69, wherein the second range determination mechanism is associated with a higher accuracy level than the first range determination mechanism, takes longer to execute than the first range determination mechanism, or any combination thereof.

72. The method of claim 69, further comprising reserving a time period during which to execute the first range determination mechanism, the second range determination mechanism, or any combination thereof.