Systems and techniques for power control

• US 20030045319A1
• Filed: 08/29/2001
• Published: 03/06/2003
• Est. Priority Date: 08/29/2001
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Chen, Tao, Sarkar, Sandip
• Granted Patent: US 6,842,624 B2
• Time in Patent Office: Days
• US Class Current: 455/522
• CPC Class Codes: H04W 52/16 Deriving transmission power values from another channel
• CPC Class Codes: H04W 52/20 using error rate
• CPC Class Codes: H04W 52/26 using transmission rate or quality of service QoS [Quality of Service]
• CPC Class Codes: H04W 52/282 taking into account the speed of the mobile
• CPC Class Codes: H04W 52/325 Power control of control or pilot channels
• CPC Class Codes: H04W 52/38 TPC being performed in particular situations
• CPC Class Codes: H04W 52/44 in connection with interruption of transmission

Abstract

Systems and techniques for power control include receiving a transmission having a channel with active portion and a silent portion, and controlling power of the received transmission as a function of a parameter of the active portion of the channel during a first time period and independent of the parameter during a second time period. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

Claims

1. A method of power control, comprising:

receiving a transmission having a channel with an active portion and a silent portion; and

controlling power of the received transmission as a function of a parameter of the active portion of the channel during a first time period and independent of the parameter during a second time period.

2. The method of claim 1 wherein the channel comprises a traffic channel.

3. The method of claim 1 wherein the parameter comprises a frame error rate of the active portion of the channel.

4. The method of claim 1 wherein the power control of the received transmission further comprises estimating power of the received transmission, and controlling the power of the received transmission further as a function of the estimated power.

5. The method of claim 4 wherein the received transmission further comprises a pilot signal, and the power estimation comprises estimating the power of the pilot signal.

6. The method of claim 4 wherein the power control of the received transmission further comprises setting a power control set point as a function of the parameter during the first time period, comparing the power control set point with the estimated power, and controlling the power of the received transmission as a function of the comparison.

7. The method of claim 6 wherein the power control further comprising increasing the power of the received transmission if the estimated power is below the power control set point and decreasing the power of the received transmission if the estimated power is above the power control set point.

8. The method of claim 6 wherein the parameter comprises a frame error rate of the active portion of the channel, and the setting of the power control set point comprises adjusting the power control set point to achieved a predetermined fixed error rate during the first time period.

9. The method of claim 6 wherein the power control of the received transmission power comprises controlling the power control set point independent of the parameter during the second time period.

10. The method of claim 9 wherein the power control of the received transmission further comprises estimating a velocity of a source of the received transmission, and controlling the power control set point as a function of the estimated velocity during the second time period.

11. The method of claim 6 wherein the power control of the received transmission further comprises detecting a transition from the active portion of the channel to the silent portion of the channel, and reducing the power control set point in response to the detected transition.

12. The method of claim 6 wherein the power control of the received transmission further comprises detecting a transition from the silent portion of the channel to the active portion of the channel, and terminating the second time period terminating after the detected transition.

13. The method of claim 6 wherein the power control of the received transmission further comprises adjusting the power control set point to a first power at the beginning of the silent portion of the channel, and adjusting the power control set point to a second power greater than the first power before the end of the silent portion of the channel.

14. The method of claim 13 further comprising scheduling the active portion of the channel.

15. The method of claim 1 wherein the first time period corresponds to the active portion of the channel and the second time period corresponds to the silent portion of the channel.

16. The method of claim 15 wherein the power control of the received transmission further comprises adjusting the power of the received transmission to a first power at the beginning of the silent portion of the channel, and adjusting the power of the received transmission to a second power greater than the first power level before the end of the silent portion of the channel.

17. The method of claim 15 wherein the power control of the received transmission further comprises estimating a velocity of a source of the received transmission, and controlling the power of the received transmission as aa function of the estimated velocity during the second time period.

18. The method of claim 1 wherein the received transmission comprises a second channel, the method further comprising setting a power ratio between the channels at the beginning of the active portion of the channel and adjusting the power ratio to a different value before the end of the active portion of the channel.

19. The method of claim 18 wherein the channel comprises a traffic channel and the second channel comprises a pilot channel.

20. The method of claim 19 wherein the adjustment of the power ratio comprises reducing relative power between the traffic channel and the pilot channel.

21. An apparatus configured to receive a transmission having a channel with an active portion and a silent portion, comprising a processor configured to estimate a parameter of the active portion of the channel, and generate a power command as a function of the estimated parameter during a first time period and independent of the estimated parameter during a second time period.

22. The apparatus of claim 21 wherein the channel comprises a traffic channel.

23. The apparatus of claim 21 wherein the parameter comprises a frame error rate of the active portion of the channel.

24. The apparatus of claim 21 wherein the processor is further configured to estimate power of the received transmission, control a power control set point as a function of the estimated parameter during the first time period, and compare the estimated power to the power control set point, the power command being a function of the comparison.

25. The apparatus of claim 21 wherein the transmission further includes a pilot signal, and the power estimation comprises estimating the power of the pilot signal.

26. The apparatus of claim 24 wherein the power command comprises a power up command if the estimated power is below the power control set point and a power down command if the estimated power is above the power control set point.

27. The apparatus of claim 24 wherein the parameter comprises a frame error rate of the active portion of the channel, and the processor is further configured to adjust the power control set point to achieved a predetermined fixed error rate during the first time period.

28. The apparatus of claim 24 wherein the processor is further configured to control the power control set point independent of the parameter during the second time period.

29. The apparatus of claim 28 wherein the processor is further configured to estimate velocity of a source of the received transmission, and control the power control set point as a function of the estimated velocity during the second time period.

30. The apparatus of claim 28 wherein the processor is further configured to detect a transition from the active portion of the channel to the silent portion of the channel, and reduce the power control set point in response to the detected transition.

31. The apparatus of claim 28 wherein the processor is further configured to detect a transition from the silent portion of the channel to the active portion of the channel, the second time period terminating after the detected transition.

32. The apparatus of claim 28 wherein the processor is further configured to adjust the power control set point to a first power at the beginning of the silent portion of the channel, and adjust the power control set point to a second power greater than the first power before the end of the silent portion of the channel.

33. The apparatus of claim 32 wherein the processor is further configured to schedule the active portion of the channel.

34. An apparatus configured to receive a transmission having a channel with an active portion and a silent portion, comprising:

parameter estimation means for estimating a parameter of the active portion of the channel; and

power command generator means for generating a power command as a function of the estimated parameter during a first time period and independent of the estimated parameter during a second time period.

35. The apparatus of claim 34 wherein the channel comprises a traffic channel.

36. The apparatus of claim 34 wherein the parameter comprises a frame error rate of the active portion of the channel.

37. The apparatus of claim 34 further comprising power estimation means for estimating power of the received transmission, set point means for setting a power control set point as a function of the estimated parameter during the first time period, and comparison means for comparing the estimated power to the power control set point, the power command being a function of the comparison.

38. The apparatus of claim 37 wherein the transmission further includes a pilot signal, and the power estimation means comprises means for estimating the power of the pilot signal.

39. The apparatus of claim 37 wherein the power command comprises a power up command if the estimated power is below the power control set point and a power down command if the estimated power is above the power control set point.

40. The apparatus of claim 37 wherein the parameter comprises a frame error rate of the active portion of the channel, and the set point means comprises means for adjusting the power control set point to achieved a predetermined fixed error rate during the first time period.

41. The apparatus of claim 37 wherein the set means comprises means for controlling the power control set point independent of the parameter during the second time period.

42. The apparatus of claim 41 further comprising velocity estimation means for estimating a velocity of a source of the received transmission, and wherein the set point means comprises means for controlling the power control set point as a function of the estimated velocity during the second time period.

43. The apparatus of claim 41 further comprising means for detecting a transition from the active portion of the channel to the silent portion of the channel, and wherein the set point means comprises means for reducing the power control set point in response to the detected transition.

44. The apparatus of claim 41 further comprising means for detecting a transition from the silent portion of the channel to the active portion of the channel, the second time period terminating after the detected transition from the silent portion to the active portion.

45. The apparatus of claim 41 wherein the set point means comprises means for adjusting the power control set point to a first power at the beginning of the silent portion of the channel, and adjusting the power control set point to a second power greater than the first power before the end of the silent portion of the channel.

46. The apparatus of claim 45 further comprising means for scheduling the active portion of the channel.

47. Computer readable media embodying a method of power control of a received transmission having an active portion and a silent portion, the method comprising controlling power of the received transmission as a function of a parameter of the active portion of the channel during a first time period and independent of the parameter during a second time period

48. The computer-readable media of claim 47 wherein the power control of the received transmission further comprises estimating power of the received transmission, and controlling the power of the received transmission further as a function of the estimated power.

49. The computer-readable media of claim 48 wherein the received transmission further comprises a pilot signal, and the power estimation comprises estimating the power of the pilot signal.

50. The computer-readable media of claim 48 wherein the power control of the received transmission further comprises setting a power control set point as a function of the parameter during the first time period, comparing the power control set point with the estimated power, and controlling the power of the received transmission as a function of the comparison.

51. The computer-readable media of claim 50 wherein the power control further comprising increasing the power of the received transmission if the estimated power is below the power control set point and decreasing the power of the received transmission if the estimated power is above the power control set point.

52. The computer-readable media of claim 50 wherein the parameter comprises a frame error rate of the active portion of the channel, and the setting of the power control set point comprises adjusting the power control set point to achieved a predetermined fixed error rate during the first time period.

53. The computer-readable media of claim 50 wherein the power control of the received transmission power comprises controlling the power control set point independent of the parameter during the second time period.

54. The computer-readable media of claim 53 wherein the power control of the received transmission further comprises estimating a velocity of a source of the received transmission, and controlling the power control set point as a function of the estimated velocity during the second time period.

55. The computer-readable media of claim 50 wherein the power control of the received transmission further comprises detecting a transition from the active portion of the channel to the silent portion of the channel, and reducing the power control set point in response to the detected transition.

56. The computer-readable media of claim 50 wherein the power control of the received transmission further comprises detecting a transition from the silent portion of the channel to the active portion of the channel, and terminating the second time period terminating after the detected transition.

57. The computer-readable media of claim 50 wherein the power control of the received transmission further comprises adjusting the power control set point to a first power at the beginning of the silent portion of the channel, and adjusting the power control set point to a second power greater than the first power before the end of the silent portion of the channel.

58. The computer-readable media of claim 57 wherein the method further comprises scheduling the active portion of the channel.

59. The computer-readable media of claim 47 wherein the first time period corresponds to the active portion of the channel and the second time period corresponds to the silent portion of the channel.

60. The computer-readable media of claim 59 wherein the power control of the received transmission further comprises adjusting the power of the received transmission to a first power at the beginning of the silent portion of the channel, and adjusting the power of the received transmission to a second power greater than the first power level before the end of the silent portion of the channel.

61. The computer-readable media of claim 59 wherein the power control of the received transmission further comprises estimating a velocity of a source of the received transmission, and controlling the power of the received transmission as aa function of the estimated velocity during the second time period.

62. The computer-readable media of claim 47 wherein the received transmission comprises a second channel, the method further comprising setting a power ratio between the channels at the beginning of the active portion of the channel and adjusting the power ratio to a different value before the end of the active portion of the channel.

63. The computer-readable media of claim 62 wherein the channel comprises a traffic channel and the second channel comprises a pilot channel, and the adjustment of the power ratio comprises reducing relative power between the traffic channel and the pilot channel.

64. An apparatus, comprising:

a transmitter configured to transmit first and second channels, the first channel having an active portion and a silent portion; and

a power control unit configured to maintain a power ratio between the first channel to the second channel during the silent period, adjust the power ratio in response to a transition from the silent portion of the channel to the active portion of the channel, and readjust the power ratio at a predetermined time after the transition.

65. The apparatus of claim 64 wherein the first channel comprises a traffic channel and the second channel comprises a pilot channel.

66. The apparatus of claim 65 wherein the power control unit is further configured to adjust the power ratio in response to the transition such that power of the traffic channel is increased with respect to power of the pilot channel.

67. The apparatus of claim 65 wherein the power control unit is further configured to readjust the power ratio at the predetermined time after the transition such that power of the traffic channel is decreased with respect to power of the pilot channel.

68. The apparatus of claim 64 further comprising a receiver configured to receive a transmission having a power command, and wherein the power control unit is further configured to control the first and second channel transmissions as a function of the power command during the active time period.

69. The apparatus of claim 68 wherein the first channel comprises a traffic channel and the second channel comprises a pilot channel.

70. The apparatus of claim 69 wherein the power control unit is further configured to adjust the power ratio in response to the transition such that power of the traffic channel is increased with respect to power of the pilot channel.

71. The apparatus of claim 69 wherein the power control unit is further configured to readjust the power ratio at the predetermined time after the transition such that power of the traffic channel is decreased with respect to power of the pilot channel.

72. An apparatus, comprising:

means for transmitting first and second channels, the first channel having an active portion and a silent portion;

means for maintaining a power ratio between the first channel and the second channel during the silent period;

adjusting means for adjusting the power ratio in response to a transition from the silent portion of the channel to the active portion of the channel; and

readjusting means for readjusting the power ratio at a predetermined time after the transition.

73. The apparatus of claim 72 wherein the first channel comprises a traffic channel and the second channel comprises a pilot channel.

74. The apparatus of claim 73 wherein the adjusting means comprises means for increasing power of the traffic channel relative to power of the pilot channel in response to the transition.

75. The apparatus of claim 73 wherein the readjusting means comprises means for decreasing power of the traffic channel relative to power of the pilot channel at the predetermined time after the transition.

76. The apparatus of claim 72 further comprising means for receiving a transmission having a power command, and means for controlling power of the first and second channel transmissions as a function of the power command during the active time period.

77. The apparatus of claim 76 wherein the first channel comprises a traffic channel and the second channel comprises a pilot channel.

78. The apparatus of claim 77 wherein the adjusting means comprises means for increasing the power of the traffic channel relative to the power of the pilot channel in response to the transition.

79. The apparatus of claim 73 wherein the readjusting means comprises means for decreasing the power of the traffic channel relative to the power of the pilot channel at the predetermined time after the transition.