Controlling reverse link interference in private access points for wireless networking

• US 20080062925A1
• Filed: 12/15/2006
• Published: 03/13/2008
• Est. Priority Date: 09/07/2006
• Status: Active Grant

• Current Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Original Assignee: Airvana Corporation (CommScope Holding Company, Inc.)
• Inventors: D'Arcy, Paul, Ananthaiyer, Satish, Mate, Amit
• Granted Patent: US 8,160,629 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04W 16/16 for PBS [Private Base Station] arrangements
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/244 Interferences in heterogeneous networks, e.g. among macro and femto or pico cells or other sector / system interference [OSI]
• CPC Class Codes: H04W 52/248 where transmission power control commands are generated based on a path parameter
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range

Abstract

In a radio access network in which a first access terminal uses a first access point to access the network and a second access terminal uses a second access point to access the network, interference is reduced in communications between the first access terminal and the first access point by adjusting signal power levels of the second access terminal without requiring coordination between the first and second access points.

Claims

1. A method comprising:

in a radio access network in which a first access terminal uses a first access point to access the network and a second access terminal uses a second access point to access the network,

reducing interference in communications between the first access terminal and the first access point by adjusting signal power levels of the second access terminal without requiring coordination between the first and second access points.

2. The method of claim 1 also comprising receiving an identification of the first access point from the second access terminal.

3. The method of claim 2 in which the identification of the first access point comprises a route update message.

4. The method of claim 1 also comprising the first access point transmitting a power control command using a first identification parameter without specific knowledge of whether any access terminals are receiving commands using the first identification parameter.

5. The method of claim 1 also comprising:

the second access point causing the second access terminal to respond to commands from the first access point that are sent using a first identification parameter, the first identification parameter being identified by the second access point without consulting the first access point.

6. The method of claim 5 in which the first identification parameter comprises a mac-index value.

7. The method of claim 5 also comprising providing the same first identification parameter to multiple second access terminals.

8. The method of claim 7 also comprising causing third access terminals to respond to commands from the first access point that are sent using a second identification parameter, the second identification parameter being identified by the second access point without consulting the first access point and being the same for all of the third access terminals.

9. The method of claim 8 in which the first identification parameter is allocated to the second access terminals and the second identification parameter is allocated to the third access terminals based at least in part on a power level of signals from the first access point at the second and third access terminals.

10. The method of claim 5 also comprising:

the second access point

causing a first group of third access terminals to respond to commands from the first access point that are sent using the first identification parameter, and

causing a second group of third access terminals to respond to commands from the first access point that are sent using a second identification parameter,

the second identification parameter being identified by the second access point without consulting the first access point.

11. The method of claim 10 also comprising the second access point receiving an identification of the first access point from each third access terminal, each identification including an indication of a power level of signals from the first access point.

12. The method of claim 1 also comprising:

the first access point transmitting commands to cause the first and second access terminals to have different behaviors.

13. The method of claim 12 in which the commands cause the first access terminal to communicate data to the first access point.

14. The method of claim 12 in which the commands cause the second access terminal to not communicate data to the first access point.

15. The method of claim 12 in which transmitting commands comprises:

transmitting a DRC-lock command to the first access terminal and transmitting a DRC-unlock command to the second access terminal.

16. The method of claim 1 also comprising:

the first access point transmitting a command associated with power levels to the second access terminal based on a determination about a rise over thermal measurement at the first access point.

17. The method of claim 16 in which the determination is that the rise over thermal measurement is less than a threshold.

18. The method of claim 17 also comprising computing the threshold based on a number of access terminals in communication with the first access point.

19. The method of claim 18 in which the number of access terminals is a number of access terminals using the first access point to access the network.

20. The method of claim 16 in which the determination is that the rise over thermal measurement is greater than a threshold.

21. The method of claim 16 in which the command allows the second access terminal to use a high signal power level.

22. The method of claim 21 in which the command comprises an RPC UP command.

23. The method of claim 16 in which the command causes the second access terminal to use a low signal power level.

24. The method of claim 16 in which the command repeatedly instructs the second access terminal to use a low signal power.

25. The method of claim 24 in which repeatedly instructing the second access terminal to use a low signal power comprises alternatingly transmitting an RPC UP command and an RPC DN command to the interfering access terminal.

26. The method of claim 25 comprising transmitting the RPC DN command a pre-determined number of times for each RPC UP command that is transmitted.

27. The method of claim 16 in which the command instructs the first access terminal and the second access terminal to use a lower bit rate.

28. The method of claim 27 also comprising:

the first access terminal determining that a pilot signal from the first access point has a power greater than a first pilot threshold, and using the command in determining whether to decrease signal power.

30. The method of claim 28 also comprising the first access terminal identifying the pilot signal from the first access point based on a DRC-lock command received from the first access point.

31. The method of claim 28 also comprising:

the first access terminal determining that a pilot signal from the second access point has a power greater than a second pilot threshold, and using the command in determining whether to decrease signal power.

32. The method of claim 31 in which the first pilot threshold is larger than the second pilot threshold.

33. The method of claim 31 also comprising the first access terminal identifying the pilot signal from the second access point based on a DRC-unlock command received from the second access point.

34. The method of claim 1 also comprising:

the second access terminal determining that a pilot signal from the first access point has a power greater than a first threshold, and decreasing signal power for data signals.

35. The method of claim 34 also comprising:

the second access terminal determining that the pilot signal from the first access point has a power greater than a second threshold, and decreasing signal power for voice signals.

36. The method of claim 35 in which the second threshold is larger than the first threshold.

37. The method of claim 1 also comprising:

the first access point, upon being powered-up or reset, transmitting commands to control power levels of the second access terminal.

38. The method of claim 37 in which the commands comprise an RPC command and a RAB stream.

39. The method of claim 1 also comprising:

modifying a radio of the first access point to transmit a per-slot rise over thermal measurement to a digital signal processor.

40. The method of claim 39 also comprising:

modifying a DSP of the first access point to

compute access terminal communication settings by comparing rise over thermal measurements to thresholds,

open a plurality of power control sub-channels for interference control signaling, and

send patterns of power control commands based on RoT measurements.

41. The method of claim 40 in which the access terminal communication settings include RAB settings.

42. The method of claim 40 in which the power control commands include RPC commands.

43. The method of claim 1 also comprising:

modifying a call control module of the first access point to allocate a-priori known traffic channels on neighboring access points.

44. The method of claim 1 also comprising:

the first access point using two or more frequencies for reverse-link communications with the second access terminal.

45. The method of claim 44 in which using two or more frequencies for reverse-link communications comprises

transmitting an RAB channel for a first frequency using a first mac-index value, and

transmitting an RAB channel for a second frequency using a second mac-index value.

46. The method of claim 44 in which using two or more frequencies for reverse-link communications comprises communicating to the second access terminal an association between mac-index values and individual frequencies of the two or more frequencies.

47. The method of claim 44 in which using two or more frequencies for reverse-link communications comprises configuring the second access terminal a-priori with an association between mac-index values and individual frequencies of the two or more frequencies.

48. The method of claim 1 in which the first access point is operated at least partially by a party other than an operator of the radio access network.

49. The method of claim 1 in which the second access point is operated by an operator of the radio access network.

50. The method of claim 1 in which the radio access network uses an Ev-DO protocol.

51. The method of claim 1 in which the radio access network uses an HSUPA protocol.

29. The method of 28 also comprising the first access terminal computing the first pilot threshold.

52. A system comprising:

a first access point to connect a first access terminal to a radio access network, and

a second access point to connect a second access terminal to the radio access network, in which the first and second access points are configured to;

reduce interference in communications between the first access terminal and the first access point by adjusting signal power levels of the second access terminal without requiring coordination between the first and second access points.

53. The system of claim 52 in which:

the second access point is configured to cause the second access terminal to respond to commands from the first access point that are sent using a first identification parameter, the first identification parameter being identified by the second access point without consulting the first access point.

54. The system of claim 52 in which the second access point is configured to:

cause a first group of third access terminals to respond to commands from the first access point that are sent using the first identification parameter, and

cause a second group of third access terminals to respond to commands from the first access point that are sent using a second identification parameter,

the second identification parameter being identified by the second access point without consulting the first access point.

55. The system of claim 54 in which the second access point is configured to receive an identification of the first access point from each third access terminal, each identification including an indication of a power level of signals from the first access point.

56. The system of claim 52 in which:

the first access point is configured to transmit a command associated with power levels to the second access terminal based on a determination about a rise over thermal measurement at the first access point.

57. The system of claim 52 in which:

the first access point is configured to, upon being powered-up or reset, transmit commands to control power levels of the second access terminal.

58. The system of claim 52 in which:

a radio of the first access point is configured to transmit a per-slot rise over thermal measurement to a digital signal processor.

59. The system of claim 57 in which:

a DSP of the first access point is configured to

compute access terminal communication settings by comparing rise over thermal measurements to thresholds,

open a plurality of power control sub-channels for interference control signaling, and

send patterns of power control commands based on RoT measurements.

60. The system of claim 52 in which:

a call control module of the first access point is configured to allocate a-priori known traffic channels on neighboring access points.

61. A computer readable medium comprising instructions to cause one or more processors in a radio access network in which a first access terminal uses a first access point to access the network and a second access terminal uses a second access point to access the network to:

reduce interference in communications between the first access terminal and the first access point by adjusting signal power levels of the second access terminal without requiring coordination between the first and second access points.

62. The medium of claim 61 in which the instructions cause:

the second access point to cause the second access terminal to respond to commands from the first access point that are sent using a first identification parameter, the first identification parameter being identified by the second access point without consulting the first access point.

63. The medium of claim 61 in which the instructions cause the second access point to:

cause a first group of third access terminals to respond to commands from the first access point that are sent using the first identification parameter, and

cause a second group of third access terminals to respond to commands from the first access point that are sent using a second identification parameter,

the second identification parameter being identified by the second access point without consulting the first access point.

64. The medium of claim 63 in which the instructions cause the second access point to receive an identification of the first access point from each third access terminal, each identification including an indication of a power level of signals from the first access point.

65. The medium of claim 61 in which the instructions cause the first access point to transmit a command associated with power levels to the second access terminal based on a determination about a rise over thermal measurement at the first access point.

66. The medium of claim 61 in which the instructions cause the first access point to, upon being powered-up or reset, transmit commands to control power levels of the second access terminal.

67. The medium of claim 61 in which the instructions cause:

a radio of the first access point to transmit a per-slot rise over thermal measurement to a digital signal processor.

68. The medium of claim 67 in which the instructions cause:

a DSP of the first access point to

compute access terminal communication settings by comparing rise over thermal measurements to thresholds,

open a plurality of power control sub-channels for interference control signaling, and

send patterns of power control commands based on RoT measurements.

69. The medium of claim 61 in which the instructions cause:

a call control module of the first access point to allocate a-priori known traffic channels on neighboring access points.

70. An apparatus comprising a first access point for use in a radio access network in which a first access terminal uses the first access point to access the network and a second access terminal uses a second access point to access the network, the apparatus configured to:

reduce interference in communications with the first access terminal by adjusting signal power levels of the second access terminal without requiring coordination with the second access point.

71. The apparatus of claim 70 also configured to transmit a power control command using a first identification parameter without specific knowledge of whether any access terminals are receiving commands using the first identification parameter.

72. The apparatus of claim 70 also configured to transmit a command associated with power levels to the second access terminal based on a determination about a rise over thermal measurement at the apparatus.

73. The apparatus of claim 70 also configured to, upon being powered-up or reset, transmit commands to control power levels of the second access terminal.

74. The apparatus of claim 70 also comprising:

a radio to transmit a per-slot rise over thermal measurement to a digital signal processor.

75. The apparatus of claim 74 also comprising:

a DSP to

compute access terminal communication settings by comparing rise over thermal measurements to thresholds,

open a plurality of power control sub-channels for interference control signaling, and

send patterns of power control commands based on RoT measurements.

76. The apparatus of claim 70 also comprising:

a call control module to allocate a-priori known traffic channels on neighboring access points.

77. The apparatus of claim 70 also configured to uses two or more frequencies for reverse-link communications with the second access terminal.