METHODS AND SYSTEMS FOR RANGING USING RANGING LOADING FACTOR

• US 20100157820A1
• Filed: 12/18/2008
• Published: 06/24/2010
• Est. Priority Date: 12/18/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Lim, Patrick, Chin, Tom, Cheng, Steven D.
• Granted Patent: US 8,179,813 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04W 36/22 for handling the traffic
• CPC Class Codes: H04W 48/06 based on traffic conditions
• CPC Class Codes: H04W 48/20 Selecting an access point

Abstract

Methods and apparatus for indicating a base station'"'"'s amount of ranging traffic to a mobile station (MS) and for selecting a base station (BS) for performing ranging based on the ranging traffic indication are provided. This notification may occur via a ranging loading parameter, such as a ranging loading factor (RLF) indicating the ratio of used ranging slots to available ranging slots, transmitted as a new TLV (Type-Length-Value) within the Uplink Channel Descriptor (UCD) of a (potential) serving BS or in the UCD of a Neighbor Advertisement (MOB_NBR-ADV) message for a neighbor BS. By selecting a BS with a certain level of unused ranging slots, the MS may exponentially decrease the ranging overhead (i.e., the average waiting time for the ranging procedures) when compared to a conventional MS that does not consider a BS'"'"'s ranging overload when trying to perform ranging with the BS.

Claims

1. A method for selecting, by a mobile station, a base station (BS) for performing ranging operations, comprising:

receiving one or more ranging loading parameters indicative of an amount of ranging traffic for one or more candidate BSs;

selecting the BS, from the candidate BSs, on which to perform ranging based, at least in part, on the ranging loading parameters; and

performing the ranging operations with the selected BS.

2. The method of claim 1, wherein the ranging loading parameters comprise one ranging loading parameter for each of the candidate BSs.

3. The method of claim 2, wherein the ranging loading parameter comprises a ranging loading factor representative of a number of used ranging slots divided by a number of available ranging slots.

4. The method of claim 2, wherein the ranging loading parameter comprises a number or a percentage of unused ranging slots.

5. The method of claim 1, wherein the ranging loading parameters comprise one ranging loading parameter for each ranging region of the candidate BSs and wherein selecting the BS comprises selecting the BS and the ranging region of the BS on which to perform ranging based, at least in part, on the ranging loading parameters.

6. The method of claim 1, wherein selecting comprises selecting a BS with a ranging loading parameter below a threshold value.

7. The method of claim 1, wherein selecting the BS comprises:

determining whether a serving BS is ranging overloaded based on a ranging loading parameter for the serving BS;

selecting the serving BS as the BS on which to perform ranging if the serving BS is not ranging overloaded; and

if the serving BS is ranging overloaded, selecting a neighbor BS from the candidate BSs as the BS on which to perform ranging.

8. The method of claim 1, wherein selecting comprises selecting the BS based on at least one of a channel-to-interference-plus-noise ratio (CINR), a Received Signal Strength Indication (RSSI), a round trip delay (RTD), scheduling service support, available resources, or a Quality of Service (QoS) in addition to the ranging loading parameters.

9. The method of claim 1, wherein selecting comprises selecting the BS, from the candidate BSs, having the lowest of the received ranging loading parameters.

10. The method of claim 1, wherein receiving the ranging loading parameters comprises receiving an Uplink Channel Descriptor (UCD) having at least one of the ranging loading parameters.

11. The method of claim 1, wherein receiving the ranging loading parameters comprises receiving a Neighbor Advertisement (MOB_NBR-ADV) message having at least one of the ranging loading parameters.

12. A computer-program product for selecting, by a mobile station, a base station (BS) for performing ranging operations, the computer-program product comprising a computer-readable medium having instructions stored thereon, the instructions being executable by one or more processors and the instructions comprising:

instructions for receiving one or more ranging loading parameters indicative of an amount of ranging traffic for one or more candidate BSs;

instructions for selecting the BS, from the candidate BSs, on which to perform ranging based, at least in part, on the ranging loading parameters; and

instructions for performing the ranging operations with the selected BS.

13. The computer-program product of claim 12, wherein the ranging loading parameters comprise one ranging loading parameter for each of the candidate BSs.

14. The computer-program product of claim 13, wherein the ranging loading parameter comprises a ranging loading factor representative of a number of used ranging slots divided by a number of available ranging slots.

15. The computer-program product of claim 13, wherein the ranging loading parameter comprises a number or a percentage of unused ranging slots.

16. The computer-program product of claim 12, wherein the ranging loading parameters comprise one ranging loading parameter for each ranging region of the candidate BSs and wherein the instructions for selecting the BS comprise instructions for selecting the BS and the ranging region of the BS on which to perform ranging based, at least in part, on the ranging loading parameters.

17. The computer-program product of claim 12, wherein the instructions for selecting comprise instructions for selecting a BS with a ranging loading parameter below a threshold value.

18. The computer-program product of claim 12, wherein the instructions for selecting the BS comprise:

instructions for determining whether a serving BS is ranging overloaded based on a ranging loading parameter for the serving BS;

instructions for selecting the serving BS as the BS on which to perform ranging if the serving BS is not ranging overloaded; and

instructions for selecting a neighbor BS from the candidate BSs as the BS on which to perform ranging if the serving BS is ranging overloaded.

19. The computer-program product of claim 12, wherein the instructions for selecting comprise instructions for selecting the BS based on at least one of a channel-to-interference-plus-noise ratio (CINR), Received Signal Strength Indication (RSSI), round trip delay (RTD), scheduling service support, available resources, or a Quality of Service (QoS) in addition to the ranging loading parameters.

20. The computer-program product of claim 12, wherein the instructions for selecting comprise instructions for selecting the BS, from the candidate BSs, having the lowest of the received ranging loading parameters.

21. The computer-program product of claim 12, wherein the instructions for receiving the ranging loading parameters comprise instructions for receiving an Uplink Channel Descriptor (UCD) having at least one of the ranging loading parameters.

22. The computer-program product of claim 12, wherein the instructions for receiving the ranging loading parameters comprise instructions for receiving a Neighbor Advertisement (MOB_NBR-ADV) message having at least one of the ranging loading parameters.

23. An apparatus for selecting a base station (BS) for performing ranging operations, comprising:

means for receiving one or more ranging loading parameters indicative of an amount of ranging traffic for one or more candidate BSs;

means for selecting the BS, from the candidate BSs, on which to perform ranging based, at least in part, on the ranging loading parameters; and

means for performing the ranging operations with the selected BS.

24. The apparatus of claim 23, wherein the ranging loading parameters comprise one ranging loading parameter for each of the candidate BSs.

25. The apparatus of claim 24, wherein the ranging loading parameter comprises a ranging loading factor representative of a number of used ranging slots divided by a number of available ranging slots.

26. The apparatus of claim 24, wherein the ranging loading parameter comprises a number or a percentage of unused ranging slots.

27. The apparatus of claim 23, wherein the ranging loading parameters comprise one ranging loading parameter for each ranging region of the candidate BSs and wherein the means for selecting the BS comprises means for selecting the BS and the ranging region of the BS on which to perform ranging based, at least in part, on the ranging loading parameters.

28. The apparatus of claim 23, wherein the means for selecting comprises means for selecting a BS with a ranging loading parameter below a threshold value.

29. The apparatus of claim 23, wherein the means for selecting the BS comprises:

means for determining whether a serving BS is ranging overloaded based on a ranging loading parameter for the serving BS;

means for selecting the serving BS as the BS on which to perform ranging if the serving BS is not ranging overloaded; and

means for selecting a neighbor BS from the candidate BSs as the BS on which to perform ranging if the serving BS is ranging overloaded.

30. The apparatus of claim 23, wherein the means for selecting comprises means for selecting the BS based on at least one of a channel-to-interference-plus-noise ratio (CINR), Received Signal Strength Indication (RSSI), round trip delay (RTD), scheduling service support, available resources, or a Quality of Service (QoS) in addition to the ranging loading parameters.

31. The apparatus of claim 23, wherein the means for selecting comprises means for selecting the BS, from the candidate BSs, having the lowest of the received ranging loading parameters.

32. The apparatus of claim 23, wherein the means for receiving the ranging loading parameters comprises means for receiving an Uplink Channel Descriptor (UCD) having at least one of the ranging loading parameters.

33. The apparatus of claim 23, wherein the means for receiving the ranging loading parameters comprises means for receiving a Neighbor Advertisement (MOB_NBR-ADV) message having at least one of the ranging loading parameters.

34. A mobile device comprising:

a receiver front end configured to receive one or more ranging loading parameters indicative of an amount of ranging traffic for one or more candidate base stations (BSs);

logic for selecting a base station (BS), from the candidate BSs, on which to perform ranging based, at least in part, on the ranging loading parameters; and

logic for performing the ranging operations with the selected BS.

35. The mobile device of claim 34, wherein the ranging loading parameters comprise one ranging loading parameter for each of the candidate BSs.

36. The mobile device of claim 35, wherein the ranging loading parameter comprises a ranging loading factor representative of a number of used ranging slots divided by a number of available ranging slots.

37. The mobile device of claim 35, wherein the ranging loading parameter comprises a number or a percentage of unused ranging slots.

38. The mobile device of claim 34, wherein the ranging loading parameters comprise one ranging loading parameter for each ranging region of the candidate BSs and wherein the logic for selecting the BS comprises logic for selecting the BS and the ranging region of the BS on which to perform ranging based, at least in part, on the ranging loading parameters.

39. The mobile device of claim 34, wherein the logic for selecting is configured to select a BS with a ranging loading parameter below a threshold value.

40. The mobile device of claim 34, wherein the logic for selecting the BS is configured to determine whether a serving BS is ranging overloaded based on a ranging loading parameter for the serving BS, to select the serving BS as the BS on which to perform ranging if the serving BS is not ranging overloaded, and, if the serving BS is ranging overloaded, to select a neighbor BS from the candidate BSs as the BS on which to perform ranging.

41. The mobile device of claim 34, wherein the logic for selecting is configured to select the BS based on at least one of a channel-to-interference-plus-noise ratio (CINR), Received Signal Strength Indication (RSSI), round trip delay (RTD), scheduling service support, available resources, or a Quality of Service (QoS) in addition to the ranging loading parameters.

42. The mobile device of claim 34, wherein the logic for selecting is configured to select the BS, from the candidate BSs, having the lowest of the received ranging loading parameters.

43. The mobile device of claim 34, wherein the receiver front end is configured to receive an Uplink Channel Descriptor (UCD) having at least one of the ranging loading parameters.

44. The mobile device of claim 34, wherein the receiver front end is configured to receive a Neighbor Advertisement (MOB_NBR-ADV) message having at least one of the ranging loading parameters.

45. A method for indicating, to a mobile station (MS), an amount of ranging traffic for a base station (BS), comprising:

determining the amount of ranging traffic for the BS; and

transmitting a ranging loading parameter indicative of the amount of ranging traffic for the BS.

46. The method of claim 45, wherein determining the amount of ranging traffic comprises dividing a number of used ranging slots by a number of available ranging slots for the BS.

47. The method of claim 45, wherein determining the amount of ranging traffic comprises determining a number or a percentage of unused ranging slots.

48. The method of claim 45, wherein determining the amount of ranging traffic comprises receiving the amount of ranging traffic or the ranging loading parameter for the BS from another BS along a backbone of a wireless communications network.

49. The method of claim 45, wherein the BS is a neighbor BS and wherein transmitting the ranging loading parameter comprises transmitting a Neighbor Advertisement (MOB_NBR-ADV) message having the ranging loading parameter for the neighbor BS.

50. The method of claim 45, wherein the BS is a serving BS and wherein transmitting the ranging loading parameter comprises transmitting an Uplink Channel Descriptor (UCD) having the ranging loading parameter for the serving BS.

51. The method of claim 45, further comprising receiving a ranging request if the ranging loading parameter is below a threshold value.

52. The method of claim 51, wherein the ranging request comprises one of a Ranging Request (RNG-REQ) message and a code-division multiple access (CDMA) ranging code.

53. A computer-program product for indicating, to a mobile station (MS), an amount of ranging traffic for a base station (BS), the computer-program product comprising a computer-readable medium having instructions stored thereon, the instructions being executable by one or more processors and the instructions comprising:

instructions for determining the amount of ranging traffic for the BS; and

instructions for transmitting a ranging loading parameter indicative of the amount of ranging traffic for the BS.

54. The computer-program product of claim 53, wherein the instructions for determining the amount of ranging traffic comprise instructions for dividing a number of used ranging slots by a number of available ranging slots for the BS.

55. The computer-program product of claim 53, wherein the instructions for determining the amount of ranging traffic comprise instructions for determining a number or a percentage of unused ranging slots.

56. The computer-program product of claim 53, wherein the instructions for determining the amount of ranging traffic comprise instructions for receiving the amount of ranging traffic or the ranging loading parameter for the BS from another BS along a backbone of a wireless communications network.

57. The computer-program product of claim 53, wherein the BS is a neighbor BS and wherein the instructions for transmitting the ranging loading parameter comprise instructions for transmitting a Neighbor Advertisement (MOB_NBR-ADV) message having the ranging loading parameter for the neighbor BS.

58. The computer-program product of claim 53, wherein the BS is a serving BS and wherein the instructions for transmitting the ranging loading parameter comprise instructions for transmitting an Uplink Channel Descriptor (UCD) having the ranging loading parameter for the serving BS.

59. The computer-program product of claim 53, further comprising instructions for receiving a ranging request if the ranging loading parameter is below a threshold value.

60. The computer-program product of claim 59, wherein the ranging request comprises one of a Ranging Request (RNG-REQ) message and a code-division multiple access (CDMA) ranging code.

61. An apparatus for indicating, to a mobile station (MS), an amount of ranging traffic for a base station (BS), comprising:

means for determining the amount of ranging traffic for the BS; and

means for transmitting a ranging loading parameter indicative of the amount of ranging traffic for the BS.

62. The apparatus of claim 61, wherein the apparatus is the BS.

63. The apparatus of claim 61, wherein the means for determining the amount of ranging traffic comprises means for dividing a number of used ranging slots by a number of available ranging slots for the BS.

64. The apparatus of claim 61, wherein the means for determining the amount of ranging traffic comprises means for determining a number or a percentage of unused ranging slots.

65. The apparatus of claim 61, wherein the means for determining the amount of ranging traffic comprises means for receiving the amount of ranging traffic or the ranging loading parameter for the BS from another BS along a backbone of a wireless communications network.

66. The apparatus of claim 61, wherein the BS is a neighbor BS and wherein the means for transmitting the ranging loading parameter comprises means for transmitting a Neighbor Advertisement (MOB_NBR-ADV) message having the ranging loading parameter for the neighbor BS.

67. The apparatus of claim 61, wherein the BS is a serving BS and wherein the means for transmitting the ranging loading parameter comprises means for transmitting an Uplink Channel Descriptor (UCD) having the ranging loading parameter for the serving BS.

68. The apparatus of claim 61, further comprising means for receiving a ranging request if the ranging loading parameter is below a threshold value.

69. The apparatus of claim 68, wherein the ranging request comprises one of a Ranging Request (RNG-REQ) message and a code-division multiple access (CDMA) ranging code.

70. A first base station (BS) for indicating, to a mobile station (MS), an amount of ranging traffic for a second BS, comprising:

logic for determining the amount of ranging traffic for the second BS; and

a transmitter front end configured to transmit a ranging loading parameter indicative of the amount of ranging traffic for the second BS.

71. The first BS of claim 70, wherein the first BS is the second BS.

72. The first BS of claim 70, wherein the logic for determining the amount of ranging traffic is configured to divide a number of used ranging slots by a number of available ranging slots for the BS.

73. The first BS of claim 70, wherein the logic for determining the amount of ranging traffic is configured to determine a number or a percentage of unused ranging slots.

74. The first BS of claim 70, wherein the logic for determining the amount of ranging traffic is configured to receive the amount of ranging traffic or the ranging loading parameter for the second BS from the second BS along a backbone of a wireless communications network.

75. The first BS of claim 70, wherein the second BS is a neighbor BS and wherein the transmitter front end is configured to transmit a Neighbor Advertisement (MOB_NBR-ADV) message having the ranging loading parameter for the neighbor BS.

76. The first BS of claim 70, wherein the first BS is a serving BS and wherein the transmitter front end is configured to transmit an Uplink Channel Descriptor (UCD) having the ranging loading parameter for the serving BS.

77. The first BS of claim 70, further comprising a receiver front end configured to receive a ranging request if the ranging loading parameter is below a threshold value.

78. The first BS of claim 77, wherein the ranging request comprises one of a Ranging Request (RNG-REQ) message and a code-division multiple access (CDMA) ranging code.