Apparatus and methods for controlling an idle mode in a wireless device

• US 8,576,760 B2
• Filed: 09/10/2009
• Issued: 11/05/2013
• Est. Priority Date: 09/12/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Gorokhov, Alexei Y., Palanki, Ravi, Kadous, Tamer A., Ulupinar, Fatih
• Primary Examiner(s): MEW, KEVIN D
• Application Number:
  US12/557,407
• Publication Number:
  US 20100067421A1
• Time in Patent Office: 1,517 Days
• Field of Search: 370/311, 370328-330, 370335-336, 370342-343, 370/345, 370436-437, 370441-442, 370449-450, 370/454, 370458-459, 370/465, 370/468
• US Class Current: 370/311
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 52/0206 in access points, e.g. base stations access point devices per se H04W88/08
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Apparatus and methods are disclosed for control of an idle mode in a wireless device. In particular, the idle mode duty cycle of a preamble transmission by an access point (AP), as an example, is variably or adaptively set in response to determined conditions of the wireless neighborhood. The conditions determined include the whether or not other wireless devices are present in the vicinity of sensing wireless device, as well as the state of those devices present, such as whether they are in an idle mode or an active mode.

Claims

1. A method for controlling an idle mode in a wireless device, the method comprising:

determining neighborhood conditions of the wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device, wherein determining neighborhood conditions of the wireless device includes determining at least another wireless device operating in an active mode or an idle mode in a vicinity of the wireless device;

adaptively setting an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions; and

transmitting the preamble transmission including a minimum distance value configured to communicate to at least one neighboring serving wireless device the presence of the at least another wireless device operating in the active mode or the idle mode in the vicinity of the wireless device.

2. The method as defined in claim 1, wherein the preamble transmission includes at least one of a pilot waveform and a preamble payload configured to at least allow discovery of the wireless device by at least one other wireless device.

3. The method as defined in claim 2, wherein the preamble payload includes at least one of an identifier particular to the wireless device, system time, a configuration of the wireless device, an idle mode configuration, and information concerning the presence and state of neighboring wireless devices.

4. The method as defined in claim 2, wherein the pilot waveform includes a portion of an identifier particular to the wireless device.

5. The method as defined in claim 1, further comprising:

adaptively setting the idle mode duty cycle to a minimal duty cycle value still affording preamble transmission when no other wireless devices are determined to be in the vicinity of the wireless device.

6. The method as defined in claim 1, further comprising:

adaptively setting the idle mode duty cycle to a value greater than a minimal duty cycle value and less than an active idle mode duty cycle value when the at least another wireless device operating in the idle mode is determined to be in the vicinity of the wireless device.

7. The method as defined in claim 1, further comprising:

adaptively setting the idle mode duty cycle to an active idle mode duty cycle when the at least another wireless device operating in the active mode is determined to be in the vicinity of the wireless device.

8. The method as defined in claim 7, wherein the value of the active idle mode duty cycle is variably determined in the wireless device based on whether the at least another wireless device operating in the active mode is currently connected to the wireless device.

9. The method as defined in claim 1, the minimum distance value further comprising at least one of:

a first minimum distance value configured for the at least another wireless device operating in an active mode; and

a second minimum distance value configured for the at least another wireless device operating in an idle mode.

12. The method as defined in claim 1, further comprising:

alternating transmitting the preamble transmission by the wireless device and receiving preamble transmissions in the wireless device from at least one neighboring wireless device during respective idle mode cycles.

13. The method as defined in claim 1, further comprising:

transmitting the preamble transmission by spreading the transmission over at least a portion of frequencies in an available wireless bandwidth.

14. The method as defined in claim 1, further comprising:

transmitting the preamble transmission by spreading the transmission over all frequencies in an available wireless bandwidth.

15. The method as defined in claim 1, further comprising:

transmitting the preamble transmission in one or more particular time slots of a wireless transmission frame.

16. The method as defined in claim 15, wherein transmitting the preamble transmission in one or more particular time slots of a wireless transmission frame includes transmission of the preamble transmission staggered or randomized based on received preamble transmissions from at least one other wireless device.

17. The method as defined in claim 15, wherein transmitting the preamble transmission in one or more particular time slots of a wireless transmission frame includes selection of time slots based on a cellID of the wireless device.

21. The method as defined in claim 1, further comprising:

transmitting paging information within one of the preamble and a dedicated paging channel to at least one neighboring unwired access point, wherein the paging information communicates paging information concerning at least one access terminal registered in a network.

22. The method as defined in claim 1, wherein determining neighborhood conditions includes determining a presence of at least one preamble demand signal from at least one neighboring wireless device,

the method further comprising further adaptively setting the idle mode duty cycle based on the at least one preamble demand signal.

23. The method as defined in claim 22, further comprising:

sending the preamble in response to the preamble demand signal.

24. The method as defined in claim 1, wherein the wireless device comprises one of an unwired access point (AP), an unwired relay station (RS), and an access terminal (AT).

10. A method for controlling an idle mode in a wireless device, the method comprising:

determining neighborhood conditions of the wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device;

adaptively setting an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions;

receiving a preamble transmission from another neighboring wireless device that includes a distance value configured to communicate distance information to at least one neighboring serving wireless device having at least one of an active wireless device and an idle wireless device operating in a coverage area of the neighboring serving wireless device; and

further adaptively setting the idle mode duty cycle based on the received distance value.

11. The method as defined in claim 10, further comprising:

incrementing the received distance value by a predetermined amount when no active wireless device is present in a coverage area of the wireless device; and

transmitting the incremented distance value to at least one further neighboring wireless device.

18. A method for controlling an idle mode in a wireless device, the method comprising:

determining neighborhood conditions of the wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device;

adaptively setting an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions;

detecting timing information from at least one preamble transmission from at least one other wireless device;

determining an earliest system time from the timing information and a system time of the wireless device based on predetermined criteria; and

slaving the system time of the wireless device to the determined earliest system time.

19. The method as defined in claim 18, wherein the predetermined criteria includes giving priority to system times of another wireless device having active wireless devices in its vicinity over system times of another wireless device having idle wireless devices in its vicinity.

20. A method for controlling an idle mode in a wireless device, the method comprising:

determining neighborhood conditions of the wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device,

wherein determining neighborhood conditions of the wireless device includes;

determining a distance from the wireless device to an idle access terminal registered in a network based on at least one distance value received from at least one neighboring wireless device; and

determining a priority class of the access terminal; and

adaptively setting an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions and dependent on the determined distance and priority class.

25. An apparatus for controlling an idle mode in a wireless device, the apparatus comprising:

means for determining neighborhood conditions of the wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device, wherein the means for determining neighborhood conditions of the wireless device determines at least another wireless device operating in an active mode or an idle mode in a vicinity of the wireless device;

means for adaptively setting an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions; and

means for transmitting the preamble transmission including a minimum distance value configured to communicate to at least one neighboring serving wireless device the presence of the at least another wireless device operating in the active mode or the idle mode in the vicinity of the wireless device.

26. The apparatus as defined in claim 25, wherein the means for adaptively setting the idle mode duty cycle is configured to set the idle mode duty cycle to a minimal duty cycle value still affording preamble transmission when no other wireless devices are determined to be in the vicinity of the wireless device by the means for determining neighborhood conditions of the wireless device.

27. The apparatus as defined in claim 25, wherein the means for adaptively setting the idle mode duty cycle is configured to set the idle mode duty cycle to a value greater than a minimal duty cycle value and less than an active idle mode duty cycle value when the at least another wireless device operating in the idle mode is determined to be in the vicinity of the wireless device by the means for determining neighborhood conditions of the wireless device.

28. The apparatus as defined in claim 25, wherein the means for adaptively setting the idle mode duty cycle is configured to set the idle mode duty cycle to an active idle mode duty cycle when the at least another wireless device operating in the active mode is determined to be in the vicinity of the wireless device by the means for determining neighborhood conditions of the wireless device.

29. The apparatus as defined in claim 28, wherein the value of the active idle mode duty cycle is variably determined in the wireless device based on whether the at least another wireless device operating in the active mode is currently connected to the wireless device.

30. The apparatus as defined in claim 25, the minimum distance value further comprising at least one of:

a first minimum distance value configured for the at least another wireless device operating in an active mode; and

a second minimum distance value configured for the at least another wireless device operating in an idle mode.

33. The apparatus as defined in claim 25, further comprising:

means for transmitting the preamble transmission in one or more particular time slots of a wireless transmission frame.

34. The apparatus as defined in claim 33, wherein transmitting the preamble transmission in one or more particular time slots of a wireless transmission frame includes transmission of the preamble transmission staggered or randomized based on received preamble transmissions from at least one other wireless device.

35. The apparatus as defined in claim 34, wherein transmitting the preamble transmission in one or more particular time slots of a wireless transmission frame includes selection of time slots based on a cellID of the wireless device.

38. The apparatus as defined in claim 25, wherein:

the means for determining neighborhood conditions includes determining a presence of at least one preamble demand signal from at least one neighboring wireless device, and

the means for adaptively setting the idle mode duty cycle is configured to set the duty cycle based on the at least one preamble demand signal.

31. An apparatus for controlling an idle mode in a wireless device, the apparatus comprising:

means for determining neighborhood conditions of the wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device;

means for adaptively setting an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions; and

means for receiving a preamble transmission from another neighboring wireless device that includes a distance value configured to communicate distance information to at least one neighboring serving wireless device having at least one of an active wireless device and an idle device operating in a coverage area of the neighboring serving wireless device,

wherein the means for adaptively setting the idle mode duty cycle sets the duty cycle based on the received distance value.

32. The apparatus as defined in claim 31, further comprising:

means for incrementing the received distance value by a predetermined amount when no active wireless device is present in a coverage area of the wireless device; and

means for transmitting the incremented distance value to at least one further neighboring wireless device.

36. An apparatus for controlling an idle mode in a wireless device, the apparatus comprising:

means for determining neighborhood conditions of the wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device;

means for adaptively setting an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions;

means for detecting timing information from at least one preamble transmission from at least one other wireless device;

means for determining an earliest system time from the timing information and a system time of the wireless device based on predetermined criteria; and

means for slaving the system time of the wireless device to the determined earliest system time.

37. An apparatus for controlling an idle mode in a wireless device, the apparatus comprising:

means for determining neighborhood conditions of the wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device; and

means for adaptively setting an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions,

wherein the means for determining neighborhood conditions of the wireless device includes;

means for determining a distance from the wireless device to an idle access terminal registered in a network based on at least one distance value received from at least one neighboring wireless device; and

means for determining a priority class of the access terminal,

wherein the means for adaptively setting the idle mode duty cycle is configured to set the duty cycle dependent on the determined distance and priority class.

39. An apparatus for controlling an idle mode in a wireless device, the apparatus comprising:

at least one processor configured to;

determine neighborhood conditions of the wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device;

adaptively set an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions; and

configure the preamble transmission including a minimum distance value configured to communicate to at least one neighboring serving wireless device the presence of at least another wireless device operating in an active mode or an idle mode in a vicinity of the wireless device when the at least one processor determines the at least another wireless device operating in the active mode or the idle mode in the vicinity of the wireless device; and

a memory configured to store instructions executable by the at least one processor.

40. The apparatus as defined in claim 39, wherein the preamble transmission includes at least one of a pilot waveform and a preamble payload configured to at least allow discovery of the wireless device by at least one other wireless device.

41. The apparatus as defined in claim 39, wherein the processor is configured to set the idle mode duty cycle to a minimal duty cycle value still affording preamble transmission when no other wireless devices are determined to be in a vicinity of the wireless device.

42. The apparatus as defined in claim 39, wherein the processor is configured to set the idle mode duty cycle to a value greater than a minimal duty cycle value and less than an active idle mode duty cycle value when the at least another wireless device operating in the idle mode is determined to be in the vicinity of the wireless device.

43. The apparatus as defined in claim 39, wherein the processor is configured to set the idle mode duty cycle to an active idle mode duty cycle when the at least another wireless device operating in the active mode is determined to be in the vicinity of the wireless device.

44. The apparatus as defined in claim 43, wherein the value of the active idle mode duty cycle is variably determined in the wireless device based on whether the at least another wireless device operating in the active mode is currently connected to the wireless device.

47. The apparatus as defined in claim 39, wherein the processor is further configured to direct alternating transmission of the preamble transmission by a transmitter in the wireless device and reception of preamble transmissions by a receiver in the wireless device from at least one neighboring wireless device during respective idle mode cycles.

48. The apparatus as defined in claim 39, wherein the processor is further configured to direct transmission of the preamble transmission by a transmitter in one or more particular time slots of a wireless transmission frame.

52. The apparatus as defined in claim 39, wherein the processor is further configured to direct transmission paging information within one of the preamble transmission and a dedicated paging channel to at least one neighboring unwired access point, wherein the paging information communicates paging information concerning at least one access terminal registered in a network.

53. The apparatus as defined in claim 39, wherein the processor is further configured to:

determine neighborhood conditions by determining the presence of at least one preamble demand signal from at least one neighboring wireless device; and

adaptively set the idle mode duty cycle based on the at least one preamble demand signal.

54. The apparatus as defined in claim 53, wherein the processor is further configured to direct sending the preamble in response to the preamble demand signal.

45. An apparatus for controlling an idle mode in a wireless device, the apparatus comprising:

at least one processor configured to;

determine neighborhood conditions of the wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device; and

adaptively set an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions;

a memory configured to store instructions executable by the at least one processor; and

a receiver configured to receive a preamble transmission from another neighboring wireless device that includes a distance value configured to communicate distance information to at least one neighboring serving wireless device having one of an active wireless device and an idle wireless device operating in a coverage area of the neighboring serving wireless device,

wherein the processor is further configured to adaptively set the idle mode duty cycle based on the received distance value.

46. The apparatus as defined in claim 45, wherein the processor is further configured to:

increment the received distance value by a predetermined amount when no active wireless device is present in a coverage area of the wireless device; and

direct transmission of the incremented distance value by a transmitter to at least one further neighboring wireless device.

49. An apparatus for controlling an idle mode in a wireless device, the apparatus comprising:

at least one processor configured to;

determine neighborhood conditions of the wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device;

adaptively set an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions;

detect timing information from at least one preamble transmission from at least one other wireless device;

determine an earliest system time from the timing information and a system time of the wireless device based on predetermined criteria; and

slave the system time of the wireless device to the determined earliest system time; and

a memory configured to store instructions executable by the at least one processor.

50. The apparatus as defined in claim 49, wherein the predetermined criteria includes giving priority to system times of another wireless device having active wireless devices in its vicinity over system times of another wireless device having idle wireless devices in its vicinity.

51. An apparatus for controlling an idle mode in a wireless device, the apparatus comprising:

at least one processor configured to;

determine neighborhood conditions of the wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device;

determine a distance from the wireless device to an idle access terminal registered in a network based on at least one distance value received from at least one neighboring wireless device;

determine a priority class of the access terminal; and

adaptively set the idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions and dependent on the determined distance and priority class; and

a memory configured to store instructions executable by the at least one processor.

55. A computer program product comprising:

a non-transitory computer-readable medium comprising;

code for causing a computer to determine neighborhood conditions of a wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device and determining at least another wireless device operating in an active mode or an idle mode in a vicinity of the wireless device;

code for causing a computer to adaptively set an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions; and

code for causing a computer to transmit the preamble transmission including a minimum distance value configured to communicate to at least one neighboring serving wireless device the presence of at the least another wireless device operating in the active mode or the idle mode in the vicinity of the wireless device.

56. The computer program product as defined in claim 55, wherein the code for causing a computer to adaptively set the idle mode duty cycle sets the idle mode duty cycle to a minimal duty cycle value still affording preamble transmission when no other wireless devices are determined to be in the vicinity of the wireless device.

57. The computer program product as defined in claim 55, wherein the code for causing a computer to adaptively set the idle mode duty cycle sets the idle mode duty cycle to a value greater than a minimal duty cycle value and less than an active idle mode duty cycle value when the at least another wireless device operating in the idle mode is determined to be in the vicinity of the wireless device.

58. The computer program product as defined in claim 55, the code for causing a computer to adaptively set the idle mode duty cycle sets the idle mode duty cycle to an active idle mode duty cycle when the at least another wireless device operating in the active mode is determined to be in the vicinity of the wireless device by the means for determining neighborhood conditions of the wireless device.

60. The computer program product as defined in claim 55, wherein the computer-readable medium further comprises:

code for causing a computer to cause transmission of the preamble transmission in one or more particular time slots of a wireless transmission frame.

59. A computer program product comprising:

a non-transitory computer-readable medium comprising;

code for causing a computer to determine neighborhood conditions of a wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device;

code for causing a computer to receive a preamble transmission from another neighboring wireless device that includes a distance value configured to communicate distance information to at least one neighboring serving wireless device having at least one of an active wireless device and an idle wireless device operating in a coverage area of the neighboring serving wireless device; and

code for causing a computer to adaptively set an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions and based on the received distance value.

61. A computer program product comprising:

a non-transitory computer-readable medium comprising;

code for causing a computer to determine neighborhood conditions of a wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device;

code for causing a computer to determine a distance from the wireless device to an idle access terminal registered in a network based on at least one distance value received from at least one neighboring wireless device;

code for causing a computer to determine a priority class of the access terminal; and

code for causing a computer to adaptively set an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions and dependent on the determined distance and priority class.

62. A computer program product comprising:

a non-transitory computer-readable medium comprising;

code for causing a computer to determine neighborhood conditions of the wireless device, which includes determining presence and states of other wireless devices in the neighborhood of the wireless device;

code for causing a computer to adaptively set an idle mode duty cycle used for at least preamble transmission by the wireless device responsive to the determined neighborhood conditions;

code for causing a computer to detect timing information from at least one preamble transmission from at least one other wireless device;

code for causing a computer to determine an earliest system time from the timing information and a system time of the wireless device based on predetermined criteria; and

code for causing a computer to slave the system time of the wireless device to the determined earliest system time.