Gain control for communications device

• US 6,748,201 B2
• Filed: 03/28/2002
• Issued: 06/08/2004
• Est. Priority Date: 03/28/2002
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Seltmann, Kevin, Black, Peter J., Sindhushayana, Nagabhushana, Challa, Raghu
• Primary Examiner(s): Urban, Edward F.
• Assistant Examiner(s): Nguyen, Thuan T.
• Application Number:
  US10/112,642
• Publication Number:
  US 20030186665A1
• Time in Patent Office: 803 Days
• Field of Search: 455/67.11, 455/115.1, 455/127.2, 455/136, 455/138, 455/219, 455/226.1, 455/232.1, 455/234.1, 455/239.1, 455/240.1, 455/245.1, 455/250.1, 455/341, 330/289-297
• US Class Current: 455/240.1
• CPC Class Codes: H03G 3/3036 in high-frequency amplifiers or in frequency-changers H03G3/3052, H03G3/32, H03G3/34 take precedence
• CPC Class Codes: H03G 3/3068 Circuits generating control signals for both R.F. and I.F. stages

Abstract

Systems and techniques for gain control include amplifying a signal with an amplifier having a gain represented by one of a plurality of gain curves depending on a value of a parameter, the signal being amplified at a first one of the parameter values, and controlling the gain of the amplified signal from a predetermined gain curve relating to the gain curve of the amplifier for a second one of the parameter values by adjusting a gain control signal corresponding to a point on the predetermined gain curve as a function of the first one of the parameter values, and applying the adjusted gain control signal to the amplifier. 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.

Claims

1. A method of gain control, comprising:

amplifying a signal with an amplifier having a gain represented by one of a plurality of gain curves depending on a value of a parameter, the signal being amplified at a first one of the parameter values; and

controlling the gain of the amplified signal from a predetermined gain curve relating to the gain curve of the amplifier for a second one of the parameter values by adjusting a gain control signal corresponding to a point on the predetermined gain curve as a function of the first one of the parameter values, and applying the adjusted gain control signal to the amplifier.

2. The method of claim 1 wherein each of the gain curves is non-linear, and the predetermined gain curve is configured to compensate for the non-linear gain curve for the second one of the parameter values.

3. The method of claim 2 wherein the gain control signal is adjusted to compensate for the non-linear gain of the amplifier at the first one of the parameter values.

4. The method of claim 1 wherein the parameter comprises frequency of the received signal.

5. The method of claim 1 wherein the parameter comprises temperature of the amplifier.

6. The method of claim 1 wherein the predetermined gain curve is stored in memory.

7. The method of claim 6 wherein the amplifier comprises a receiver, and wherein the adjustment of the gain control signal comprises estimating power of the amplified signal from the receiver, and adjusting the estimated power as a function of the first one of the parameter values to address the memory.

8. The method of claim 6 wherein the amplifier comprises a transmitter, the method further comprising amplifying a received signal with a receiver, and wherein the adjustment of the gain control signal comprises estimating power of the amplified signal from the receiver, and adjusting the estimated power as a function of the first one of the parameter values to address the memory.

9. The method of claim 6 wherein the adjustment of the gain control signal comprises adjusting the gain control signal in memory as a function of the first one of the parameter values.

10. The method of claim 6 wherein the gain control signal is determined by interpolating between two points on the predetermined gain curve.

11. The method of claim 1 wherein each of the gain curves of the amplifier further depend on a value of a second parameter, the signal being amplified at one of the second parameter values, and wherein the predetermined gain curve further relates to a second one of the second parameter values, and the adjustment of the gain control signal further comprises adjusting the gain control signal as a function of the first one of the second parameter values.

12. The method of claim 11 wherein the parameter comprises frequency of the received signal, and the second parameter comprises temperature of the amplifier.

13. The method of claim 11 wherein the predetermined gain curve is stored in memory.

14. The method of claim 13 wherein the amplifier comprises a receiver, and wherein the adjustment of the gain control signal further comprises estimating power of the amplified signal from the receiver, adjusting the estimated power as a function of the first one of the parameter values to address the memory, reading from the memory the gain control signal from the predetermined gain curve corresponding to the address, adjusting the address as a function of the first one of the second parameter values, and adjusting the gain control signal read from the memory as a function of the first one of the second parameter values and the adjusted address.

15. The method of claim 13 wherein the amplifier comprises a transmitter, the method further comprising amplifying a received signal with a receiver, and wherein the adjustment of the gain control signal further comprises estimating power of the amplified signal from the receiver, adjusting the estimated power as a function of the first one of the parameter values to address the memory, reading from the memory the gain control signal from the predetermined gain curve corresponding to the address, adjusting the address as a function of the first one of the second parameter values, and adjusting the gain control signal read from the memory as a function of the first one of the second parameter values and the adjusted address.

16. The method of claim 15 wherein the gain control signal is determined by interpolating between two points on the predetermined gain curve.

17. The method of claim 1 further comprising copying the predetermined gain curve from a first memory to a second memory, the gain control signal corresponding to a point on the predetermined gain curve from the second memory.

18. An apparatus, comprising:

an amplifier having a gain represented by one of a plurality of gain curves depending on a value of a parameter; and

a gain control configured to control the gain of the amplifier from a predetermined gain curve relating to the gain curve of the amplifier for a first one of the parameter values by adjusting a gain control signal corresponding to a point on the predetermined gain curve as a function of a second one of the parameter values, and applying the adjusted gain control signal to the amplifier.

19. The apparatus of claim 18 wherein the parameter comprises frequency of a signal to be amplified by the amplifier.

20. The apparatus of claim 18 wherein the parameter comprises temperature of the amplifier.

21. The apparatus of claim 18 wherein each of the gain curves is non-linear, and wherein the predetermined gain curve is configured to compensate for the non-linear gain curve for the first one of the parameter values.

22. The apparatus of claim 21 wherein the gain control is further configured to adjust the gain control signal to compensate for the non-linear gain of the amplifier at the second one of the parameter values.

23. The apparatus of claim 18 wherein the gain control comprises memory configured to store the predetermined gain curve.

24. The apparatus of claim 23 wherein the gain control further comprises an interpolator configured to determine the gain control signal from two points on the predetermined gain curve.

25. The apparatus of claim 23 wherein the amplifier comprises a receiver, and wherein the gain control further comprises a power estimator configured to estimate power output from the receiver, and an operator configured to adjust the estimated power as a function of the second one of the parameter values to address the memory.

26. The apparatus of claim 23 further comprises a receiver, wherein the amplifier comprises a transmitter, and the gain control further comprises a power estimator configured to estimate power output from the receiver, and an operator configured to adjust the estimated power as a function of the second one of the parameter values to address the memory.

27. The apparatus of claim 26 wherein the operator comprises an adder.

28. The apparatus of claim 23 wherein the gain control further comprises a combiner configured to adjust the gain control signal as a function of the second one of the parameter values.

29. The apparatus of claim 28 wherein the operator comprises an adder.

30. The apparatus of claim 18 wherein each of the gain curves of the amplifier further depends on a value of a second parameter, and the predetermined gain curve further relates to a first one of the second parameter values, and wherein the gain control adjusts the gain control signal as a function of a second one of the second parameter values.

31. The apparatus of claim 30 wherein the parameter comprises frequency of a signal to be amplified by the amplifier, and the second parameter comprises temperature of the amplifier.

32. The apparatus of claim 30 wherein the gain control further comprises memory configured to store the predetermined gain curve.

33. The apparatus of claim 32 wherein the gain control further comprises an interpolator configured to determine the gain control signal from two points on the predetermined gain curve.

34. The apparatus of claim 32 wherein the amplifier comprises a receiver, and the gain control further comprises a power estimator configured to estimate power output from the receiver, a first operator configured to adjust the estimated power as a function of the second one of the parameter values to address the memory, a second operator configured to adjust the address as a function of the second one of the second parameter values, and a third operator configured to adjust the gain control signal from memory as a function of the second one of the second parameter values as a function of the adjusted address.

35. The apparatus of claim 32 further comprising a receiver, wherein the amplifier comprises a transmitter, and the gain control further comprises a power estimator configured to estimate power output from the receiver, a first operator configured to adjust the estimated power as a function of the second one of the parameter values to address the memory, a second operator configured to adjust the address as a function of the second one of the second parameter values, and a third operator configured to adjust the gain control signal from memory as a function of the second one of the second parameter values as a function of the adjusted address.

36. The apparatus of claim 35 wherein the first and third operators each comprises an adder, and the second operator comprises a multiplier.

37. The apparatus of claim 18 further comprising a first memory configured to store the predetermined gain curve, and wherein the gain control comprises a second memory, the gain control being further configured to copy the predetermined gain curve from the first memory to the second memory, the gain control signal corresponding to a point on the predetermined gain curve from the second memory.

38. Computer readable media embodying a method of controlling gain of an amplifier having a gain represented by one of a plurality of gain curves depending on a value of a parameter, the method comprising:

storing a predetermined gain curve relating to the gain curve of the amplifier for a first one of the parameter values;

adjusting a gain control signal corresponding to a point on the predetermined gain curve as a function of a second one of the parameter values; and

applying the adjusted gain control signal to the amplifier.

39. The computer readable media of claim 38 wherein each of the gain curves is non-linear, and the predetermined gain curve is configured to compensate for the non-linear gain curve for the first one of the parameter values.

40. The computer readable media of claim 39 wherein the gain control signal is adjusted to compensate for the non-linear gain of the amplifier at the second one of the parameter values.

41. The computer readable media of claim 38 wherein the parameter comprises frequency of a signal to be amplified.

42. The computer readable media of claim 38 wherein the parameter comprises temperature of the amplifier.

43. The computer readable media of claim 38 wherein the predetermined gain curve is stored in memory.

44. The computer readable media of claim 43 wherein the amplifier comprises a receiver, and wherein the adjustment of the gain control signal comprises estimating power output from the receiver, and adjusting the estimated power as a function of the second one of the parameter values to address the memory.

45. The computer readable media of claim 43 wherein the amplifier comprises a transmitter, the method further comprising amplifying a received signal with a receiver, and wherein the adjustment of the gain control signal comprises estimating power output from the receiver, and adjusting the estimated power as a function of the second one of the parameter values to address the memory.

46. The computer readable media of claim 43 wherein the adjustment of the gain control signal comprises adjusting the gain control signal as a function of the second one of the parameter values.

47. The computer readable media of claim 43 wherein the gain control signal is determined by interpolating between two points on the predetermined gain curve.

48. The computer readable media of claim 38 wherein each of the gain curves of the amplifier further depend on a value of a second parameter, and wherein the predetermined gain curve further relates to a first one of the second parameter values, and the adjustment of the gain control signal further comprises adjusting the gain control signal as a function of the second one of the second parameter values.

49. The computer readable media of claim 48 wherein the parameter comprises frequency of a signal to be amplified by the amplifier, and the second parameter comprises temperature of the amplifier.

50. The computer readable media of claim 48 wherein the predetermined gain curve is stored in memory.

51. The computer readable media of claim 50 wherein the amplifier comprises a receiver, and wherein the adjustment of the gain control signal further comprises estimating power output from the receiver, adjusting the estimated power as a function of the second one of the parameter values to address the memory, reading from the memory the gain control signal from the predetermined gain curve corresponding to the address, adjusting the address as a function of the second one of the second parameter values, and adjusting the gain control signal read from the memory as a function of the second one of the second parameter values and the adjusted address.

52. The computer readable media of claim 50 wherein the amplifier comprises a transmitter, the method further comprising amplifying a received signal with a receiver, and wherein the adjustment of the gain control signal further comprises estimating power output from the receiver, adjusting the estimated power as a function of the second one of the parameter values to address the memory, reading from the memory the gain control signal from the predetermined gain curve corresponding to the address, adjusting the address as a function of the second one of the second parameter values, and adjusting the gain control signal read from the memory as a function of the second one of the second parameter values and the adjusted address.

53. The computer readable media of claim 50 wherein the gain control signal is determined by interpolating between two points on the predetermined gain curve.

54. The computer readable media of claim 38 wherein the method further comprises copying the predetermined gain curve from a first memory to a second memory, the gain control signal corresponding to a point on the predetermined gain curve from the second memory.

55. An apparatus, comprising:

amplifier means for amplifying a signal, the amplifier means having a gain represented by one of a plurality of gain curves depending on a value of a parameter; and

gain control means for controlling the gain of the amplifier from a predetermined gain curve relating to the gain curve of the amplifier means for a first one of the parameter values by adjusting a gain control signal corresponding to a point on the predetermined gain curve as a function of a second one of the parameter values, and applying the adjusted gain control signal to the amplifier.

56. The apparatus of claim 55 wherein the parameter comprises frequency of the received signal.

57. The apparatus of claim 55 wherein the parameter comprises temperature of the amplifier means.

58. The apparatus of claim 55 wherein each of the gain curves is non-linear, and wherein the predetermined gain curve is configured to compensate for the non-linear gain curve for the first one of the parameter values.

59. The apparatus of claim 58 wherein the gain control means signal generator is further configured to adjust the gain control signal to compensate for the non-linear gain of the amplifier means at the second one of the parameter values.

60. The apparatus of claim 55 wherein the gain control means comprises memory means for storing the predetermined gain curve.

61. The apparatus of claim 60 wherein the gain control means further comprises means for interpolating between two points on the predetermined gain curve to determine the gain control signal.

62. The apparatus of claim 60 wherein the amplifier means comprises a receiver, and the gain control means further means for estimating power output from the receiver, and means for adjusting the estimated power as a function of the second one of the parameter values to address the memory means.

63. The apparatus of claim 60 further comprising a receiver, wherein the amplifier means comprises a transmitter, and the gain control means further means for estimating power output from the receiver, and means for adjusting the estimated power as a function of the second one of the parameter values to address the memory means.

64. The apparatus of claim 60 wherein the gain control means further comprises means for adjusting the gain control signal from the memory as a function of the second one of the parameter values.

65. The apparatus of claim 55 wherein each of the gain curves of the amplifier means further depends on a value of a second parameter, and the predetermined gain curve further relates to a first one of the second parameter values, and wherein the gain control means adjusts the gain control signal as a function of a second one of the second parameter values.

66. The apparatus of claim 65 wherein the parameter comprises frequency of a signal to be amplified by the amplifier means, and the second parameter comprises temperature of the amplifier means.

67. The apparatus of claim 65 wherein the gain control means further comprises memory means for storing the predetermined gain curve.

68. The apparatus of claim 67 wherein the gain control means further comprises means for interpolating between two points on the predetermined gain curve to determine the gain control signal.

69. The apparatus of claim 65 wherein the amplifier means comprises a receiver, and the gain control means comprises means for estimating power output from the receiver, means for adjusting the estimated power as a function of the second one of the parameter values to address the memory means, means for adjusting the address as a function of the second one of the second parameter values, and means for adjusting the gain control signal from memory as a function of the second one of the second parameter values as a function of the adjusted address.

70. The apparatus of claim 65 further comprising a receiver, wherein the amplifier means comprises a transmitter, and the gain control means comprises means for estimating power output from the receiver, means for adjusting the estimated power as a function of the second one of the parameter values to address the memory means, means for adjusting the address as a function of the second one of the second parameter values, and means for adjusting the gain control signal from memory as a function of the second one of the second parameter values as a function of the adjusted address.

71. The apparatus of claim 55 further comprising a first memory means for storing the predetermined gain curve, and wherein the gain control means comprises second memory means and means for copying the predetermined gain curve from the first memory means into the second memory, the gain control signal corresponding to a point on the predetermined gain curve from the second memory means.

72. An apparatus, comprising:

a receiver having a gain represented by one of a plurality of receiver gain curves depending on a value of a receiver parameter;

a transmitter having a gain represented by one of a plurality of transmitter gain curves depending on a value of a transmitter parameter; and

a gain control configured to control the gain of the receiver from a predetermined receiver gain curve relating to the receiver gain curve of the receiver for a first one of the receiver parameter values by adjusting a receiver gain control signal corresponding to a point on the predetermined gain curve as a function of a second one of the receiver parameter values, and applying the adjusted receiver gain control signal to the receiver, the gain control further being configured to control the gain of the transmitter from a predetermined transmitter gain curve relating to the transmitter gain curve of the transmitter for a first one of the transmitter parameter values by adjusting a transmitter gain control signal corresponding to a point on the predetermined transmitter gain curve as a function of a second one of the transmitter parameter values, and applying the adjusted transmitter gain control signal to the transmitter.

73. The apparatus of claim 72 wherein the receiver parameter comprises frequency of a signal to be amplified by the receiver, and the transmitter parameter comprises frequency of the signal to be amplified by the transmitter.

74. The apparatus of claim 72 wherein the receiver parameter comprises temperature of the receiver, and the transmitter parameter comprises temperature of the transmitter.

75. The apparatus of claim 72 wherein each of the receiver and transmitter gain curves is non-linear, and wherein the predetermined receiver gain curve is configured to compensate for the non-linear receiver gain curve for the first one of the receiver parameter values and the predetermined transmitter gain curve is configured to compensate for the non-linear transmitter gain curve for the first one of the transmitter parameter values.

76. The apparatus of claim 75 wherein the gain control is further configured to adjust the receiver gain control signal to compensate for the non-linear gain of the receiver at the second one of the receiver parameter values, and adjust the transmitter gain control signal to compensate for the non-linear gain of the transmitter at the second one of the transmitter parameter values.

77. The apparatus of claim 72 wherein the gain control comprises a power estimator configured to estimate power output from the receiver, and memory configured to store the predetermined receiver and transmitter gain curves, the adjustment of the receiver and transmitter gain control signals from their respective predetermined gain curves being a function of the estimated power.

78. The apparatus of claim 77 wherein the memory comprises a receiver memory configured to store the predetermined receiver gain curve and a transmitter memory configured to store the predetermined transmitter gain curve.

79. The apparatus of claim 78 wherein the gain control further comprises a receiver interpolator configured to determine the receiver gain control signal from two points on the predetermined receiver gain curve from receiver memory, and a transmitter interpolator configured to determine the transmitter gain control signal from two points on the predetermined transmitter gain curve from transmitter memory.

80. The apparatus of claim 72 wherein each of the receiver gain curves of the receiver further depends on a value of a second receiver parameter, and the predetermined receiver gain curve further relates to a first one of the second receiver parameter values, and wherein the gain control adjusts the receiver gain control signal as a function of a second one of the second receiver parameter values, and wherein each of the transmitter gain curves of the transmitter further depends on a value of a second transmitter parameter, and the predetermined transmitter gain curve further relates to a first one of the second transmitter parameter values, and wherein the gain control adjusts the transmitter gain control signal as a function of a second one of the second transmitter parameter values.

81. The apparatus of claim 80 wherein the receiver parameter comprises frequency of a signal to be amplified by the receiver, the transmitter parameter comprises frequency of a signal to be amplified by the transmitter, the second receiver parameter comprises temperature of the receiver, and the second transmitter parameter comprises temperature of the transmitter.

82. The apparatus of claim 80 wherein the gain control comprises a power estimator configured to estimate power output from the receiver, and memory configured to store the receiver and transmitter predetermined gain curves, the adjustment of the receiver and transmitter gain control signals from their respective predetermined gain curves being a function of the estimated power.

83. The apparatus of claim 82 wherein the memory comprises a receiver memory configured to store the predetermined receiver gain curve and a transmitter memory configured to store the predetermined transmitter gain curve.

84. The apparatus of claim 83 wherein the gain control further comprises a first operator configured to adjust the estimated power as a function of the second one of the receiver parameter values to address the receiver memory, a second operator configured to adjust the address to the receiver memory as a function of the second one of the second receiver parameter values, a third operator configured to adjust the receiver gain control signal from the receiver memory as a function of the second one of the second receiver parameter values as a function of the adjusted address to the receiver memory, a fourth operator configured to adjust the estimated power as a function of the second one of the transmitter parameter values to address the transmitter memory, a fifth operator configured to adjust the address to the transmitter memory as a function of the second one of the second transmitter parameter values, and a sixth operator configured to adjust the transmitter gain control signal from the transmitter memory as a function of the second one of the second transmitter parameter values as a function of the adjusted address to the transmitter memory.

85. The apparatus of claim 84 wherein the first, third, fourth and sixth operators each comprises an adder, and the second and fifth operators each comprises a multiplier.

86. The apparatus of claim 72 further comprising a first memory configured to store the predetermined receiver and transmitter gain curves, and wherein the gain control comprises a second memory, the gain control being further configured to copy the predetermined receiver and transmitter gain curves from the first memory to the second memory, the receiver and transmitter gain control signals each corresponding to a point on their respective predetermined gain curves from the second memory.