Apparatus and method for optimizing the quality of a received signal in a radio receiver

• US 5,758,271 A
• Filed: 11/25/1997
• Issued: 05/26/1998
• Est. Priority Date: 06/02/1995
• Status: Expired due to Term

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Rich, Randall W., Vilmur, Richard J.
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): BANKS HAROLD, MARSHA DENISE
• Application Number:
  US08/978,099
• Time in Patent Office: 182 Days
• Field of Search: 455/226.1, 455/226.2, 455/226.3, 455/63, 455/67.1, 455/67.3, 455/234.1, 455/240.1, 455/245.1, 455/234.2, 455/296, 455/295, 455/246.1, 455/247.1
• US Class Current: 455/234.1
• CPC Class Codes: H04W 52/18 TPC being performed according to specific parameters

Abstract

A code division multiple access (CDMA) radio receiver (104) having gain receives a radio frequency (RF) signal (122) to produce a received signal (124). The quality (130) of the received signal (124) is determined (111). The quality (130) is preferably a ratio of an energy per chip of a desired signal (Ec) to a total power spectral density of the received signal (Io) (124). For alternative radio receivers (104) the quality (130) may be an error rate estimate of a demodulated signal (126). The gain of the radio receiver (104) is adjusted responsive to the quality (130) of the received signal (124) to optimize the quality (130) of the received signal (124). Further, since the adjusted gain also changes a received signal strength indication (RSSI) (242) of the received signal (124), the RSSI (242) of the received signal (124) is estimated (217) and compensated (218) responsive to the gain of the radio receiver (104) to produce a compensated RSSI (134) of the received signal (124) indicative of the RSSI of a desired RF signal (122).

Claims

1. A method for optimizing a quality of a received signal in a radio receiver having gain, the method comprising the steps of:

receiving a radio frequency (RF) signal to produce the received signal;

determining the quality of the received signal;

estimating a received signal strength indication (RSSI of the received signal, determining whether the quality of the received signal is favorable or unfavorable;

determining whether the RSSI of the received signal is favorable or unfavorable; and

adjusting the gain of the radio receiver responsive to the quality of the received signal when both the quality of the received signal and the RSSI of the received signal are favorable, and

not adjusting the gain of the radio receiver when either the quality or the RSSI of the received signal is unfavorable or both the quality of the received signal and the RSSI of the received signal are unfavorable.

2. A method according to claim 1 wherein the received signal includes a desired signal and an undesired signal, and wherein the quality of the received signal further comprises:

a ratio indicative of the desired signal to the received signal.

3. A method according to claim 2 wherein the ratio further comprises:

an energy per chip of the desired signal (Ec) to a total power spectral density of the received signal (Io).

4. A method according to claim 1 further comprising the step of:

demodulating the received signal to produce a demodulated signal;

wherein the step of determining the quality of the received signal further comprises the step of estimating an error rate of the demodulated signal; and

wherein the step of adjusting is performed responsive to the error rate of the demodulated signal.

5. A method according to claim 1 wherein the RF signal includes a desired RF signal and an undesired RF signal, the method further comprising the steps of:

compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

6. A method according to claim 1 further comprising the step of:

generating a gain control signal responsive to the quality of the received signal;

wherein the step of adjusting is performed responsive to the gain control signal.

7. A method according to claim 6 wherein the step of generating further comprises the steps of:

comparing a present measurement of the quality of the received signal with a past measurement of the quality of the received signal to produce a first output signal;

comparing a present measurement of the gain with a past measurement of the gain to produce a second output signal; and

determining the gain control signal responsive to the first and second output signals.

8. A method according to claim 7 wherein the step of determining further comprises the steps of:

multiplying the first output signal and the second output signal to produce a multiplied signal;

multiplying the multiplied signal by a predetermined gain control step value to produce a gain control step signal; and

summing the gain control step signal with a present gain control signal to produce a future gain control signal.

9. A method according to claim 6 further comprising the step of:

limiting the gain control signal between a maximum value and a minimum value.

10. A method according to claim 6 wherein the RF signal includes a desired RF signal and an undesired RF signal, the method further comprising the step of:

limiting the gain control signal to a maximum value responsive to a received signal strength indication (RSSI) of the desired RF signal.

11. A method according to claim 6 further comprising the step of:

determining whether the gain control signal is favorable or unfavorable;

adjusting a first gain stage of the radio receiver when the gain control signal is favorable; and

adjusting a second gain stage of the radio receiver when the gain control signal is unfavorable.

12. A method for optimizing a quality of a received signal in a radio receiver having gain, wherein the received signal includes a desired signal and an undesired signal, the method comprising the steps of:

receiving a radio frequency (RF) signal to produce the received signal;

determining the quality of the received signal, wherein the quality of the received signal further comprises a ratio indicative of the desired signal to the received signal;

comparing a present measurement of the quality of the received signal with a past measurement of the quality of the received signal to produce a first output signal;

comparing a present measurement of the gain with a past measurement of the gain to produce a second output signal;

multiplying the first output signal and the second output signal to produce a multiplied signal;

multiplying the multiplied signal by a predetermined gain control step value to produce a gain control step signal;

summing the gain control step signal with a present gain control signal to produce a future gain control signal; and

adjusting the gain of the radio receiver responsive to the future gain control signal.

13. A method according to claim 12 wherein the ratio further comprises:

an energy per chip of the desired signal (Ec) to a total power spectral density of the received signal (Io).

14. A method according to claim 12 wherein

the RF signal includes a desired RF signal and an undesired RF signal, the method further comprising the steps of:

estimating a received signal strength indication (RSSI) of the received signal; and

compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

15. A method according to claim 12 further comprising the step of:

limiting the gain control signal between a maximum value and a minimum value.

16. A method according to claim 12 wherein the RF signal includes a desired RF signal and an undesired RF signal, the method further comprising the step of:

limiting the gain control signal to a maximum value responsive to a received signal strength indication (RSSI) of the desired RF signal.

17. A method according to claim 12 further comprising the step of:

determining whether the gain control signal is favorable or unfavorable;

adjusting a first gain stage of the radio receiver when the gain control signal is favorable; and

adjusting a second gain stage of the radio receiver when the gain control signal is unfavorable.

18. A method for optimizing a quality of a received signal in a radio receiver having gain, wherein the received signal includes a desired signal and an undesired signal, the method comprising the steps of:

receiving a radio frequency (RF) signal to produce the received signal;

determining the quality of the received signal, wherein the quality of the received signal further comprises a ratio indicative of the desired signal to the received signal, wherein the ratio further comprises an energy per chip of the desired signal (Ec) to a total power spectral density of the received signal (Io);

comparing a present measurement of the quality of the received signal with a past measurement of the quality of the received signal to produce a first output signal;

comparing a present measurement of the gain with a past measurement of the gain to produce a second output signal;

multiplying the first output signal and the second output signal to produce a multiplied signal;

multiplying the multiplied signal by a predetermined gain control step value to produce a gain control step signal;

summing the gain control step signal with a present gain control signal to produce a figure gain control signal; and

adjusting the gain of the radio receiver responsive to the future gain control signal.

19. A method according to claim 18 wherein the RF signal includes a desired RF signal and an undesired R signal, the method further comprising the steps of:

estimating a received signal strength indication (RSSI) of the received signal; and

compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

20. A method according to claim 18 further comprising the step of:

limiting the gain control signal between a maximum value and a minimum value.

21. A method according to claim 18 wherein the RF signal includes a desired RF signal and an undesired RE signal, the method further comprising the step of:

limiting the gain control signal to a maximum value responsive to a received signal strength indication (RSSI) of the desired RF signal.

22. A method according to claim 18 further comprising the step of:

determining whether the gain control signal is favorable or unfavorable;

adjusting a first gain stage of the radio receiver when the gain control signal is favorable; and

adjusting a second gain stage of the radio receiver when the gain control signal is unfavorable.

23. An apparatus for optimizing a quality of a received signal in a radio receiver having gain, the apparatus comprising:

a receiver for receiving a radio frequency (RF) signal to produce the received signal;

a signal quality determiner for determining the quality of the received signal;

a received signal strength indication (RSSI) estimator for estimating the RSSI of the received signal;

a first comparator for determining whether the quality of the received signal is favorable or unfavorable;

a second comparator for determining whether the RSSJ of the received signal is favorable or unfavorable; and

a gain controller for adjusting the gain of the radio receiver responsive to the quality of the received signal when both the quality of the received signal and the RSSI of the received signal are favorable, and for not adjusting the gain of the radio receiver when either the quality of the received signal or the RSSI of the received signal is unfavorable or both the quality of the received signal and the RSSI of the received signal are unfavorable.

24. An apparatus according to claim 23 wherein the received signal includes a desired signal and an undesired signal, and wherein the quality of the received signal further comprises:

a ratio indicative of the desired signal to the received signal.

25. An apparatus according to claim 24 wherein the ratio further comprises:

an energy per chip of the desired signal (Ec) to a total power spectral density of the received signal (Io).

26. An apparatus according to claim 23 further:

a demodulator for demodulating the received signal to produce a demodulated signal;

wherein the signal quality determiner further comprises an error rate estimator for estimating an error rate of the demodulated signal; and

wherein gain controller adjusts the gain of the radio receiver responsive to the error rate of the demodulated signal.

27. An apparatus according to claim 23 wherein the RF signal includes a desired RP signal and an undesired RF signal, the apparatus further comprising:

a RSSI compensator for compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

28. An apparatus according to claim 23:

wherein the gain controller generates a gain control signal responsive to the quality of the received signal; and

wherein the gain controller adjusts the gain of the radio receiver responsive to the gain control signal.

29. An apparatus according to claim 28 wherein the gain controller further comprises:

a first comparator for comparing a present measurement of the quality of the received signal with a past measurement of the quality of the received signal to produce a first output signal;

a second comparator for comparing a present measurement of the gain with a past measurement of the gain to produce a second output signal; and

a gain control signal determiner for determining the gain control signal responsive to the first and second output signals.

30. An apparatus according to claim 29 wherein the gain control signal determiner further comprises:

a first multiplier for multiplying the first output signal and the second output signal to produce a multiplied signal;

a second multiplier for multiplying the multiplied signal by a predetermined gain control step value to produce a gain control step signal; and

a summer for summing the gain control step signal with a present gain control signal to produce a future gain control signal.

31. An apparatus according to claim 28 wherein the gain controller further comprises:

a limiter for limiting the gain control signal between a maximum value and a minimum value.

32. An apparatus according to claim 28 wherein the RF signal includes a desired RF signal an undesired RF signal, wherein the gain controller further comprises:

a limiter for limiting the gain control signal to a maximum value responsive to a received signal strength indication (RSSI) of the desired RF signal.

33. An apparatus according to claim 28 wherein the gain controller further comprises:

a gain control signal determiner for determining whether the gain control signal is favorable or unfavorable; and

a switch permitting the gain controller to adjust a first gain stage of the radio receiver when the gain control signal is favorable and to adjust a second gain stage of the radio receiver when the gain control signal is unfavorable.

34. An apparatus for optimizing a quality of a received signal in a radio receiver having gain, wherein the received signal includes a desired signal and an undesired signal, the apparatus comprising:

a receiver for receiving a radio frequency (RF) signal to produce the received signal;

a signal quality determiner for determining the quality of the received signal, wherein the quality of the received signal further comprises a ratio indicative of the desired signal to the received signal;

a gain controller comprising;

a first comparator for comparing a present measurement of the quality of the received signal with a past measurement of the quality of the received signal to produce a first output signal;

a second comparator for comparing a present measurement of the gain with a past measurement of the gain to produce a second output signal;

a first multiplier for multiplying the first output signal and the second output signal to produce a multiplied signal;

a second multiplier for multiplying the multiplied signal by a predetermined gain control step value to produce a gain control step signal; and

a summer for summing the gain control step signal with a present gain control signal to produce a future gain control signal;

wherein the gain controller adjusts the gain of the radio receiver responsive to the future gain control signal.

35. An apparatus according to claim 34 wherein the ratio further comprises:

an energy per chip of the desired signal (Ec) to a total power spectral density of the received signal (Io).

36. An apparatus according to claim 34 wherein the RF signal includes a desired RF signal an undesired RF signal, the apparatus further comprising:

a received signal strength indication (RSSI) estimator for estimating the RSSI of the received signal; and

a RSSI compensator for compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

37. An apparatus according to claim 34 further comprising:

a limiter for limiting the gain control signal between a maximum value and a minimum value.

38. An apparatus according to claim 34 wherein the RF signal includes a desired RF signal and an undesired RE signal, the apparatus further comprising:

a limiter for limiting the gain control signal to a maximum value responsive to a received signal strength indication (RSSI) of the desired RF signal.

39. An apparatus according to claim 34 further comprising:

a gain control signal determininer for determining whether the gain control signal is favorable or unfavorable; and

a switch permitting the gain controller to adjust a first gain stage of the radio receiver when the gain control signal is favorable and to adjust a second gain stage of the radio receiver when the gain control signal is unfavorable.

40. An apparatus for optimizing a quality of a received signal in a radio receiver having gain, wherein the received signal includes a desired signal and an undesired signal, the apparatus comprising:

a receiver for receiving a radio frequency (RF) signal to produce the received signal;

a signal quality determiner for determining the quality of the received signal, wherein the quality of the received signal further comprises a ratio indicative of the desired signal to the received signal, wherein the ratio further comprises an energy per chip of the desired signal (Ec) to a total power spectral density of the received signal (Io);

a gain controller comprising;

a first comparator for comparing a present measurement of the quality of the received signal with a past measurement of the quality of the received signal to produce a first output signal;

a second comparator for comparing a present measurement of the gain with a past measurement of the gain to produce a second output signal;

a first multiplier for multiplying the first output signal and the second output signal to produce a multiplied signal;

a second multiplier for multiplying die multiplied signal by a predetermined gain control step value to produce a gain control step signal; and

a summer for summing the gain control step signal with a present gain control signal to produce a future gain control signal;

wherein the gain controller adjusts the gain of the radio receiver responsive to the future gain control signal.

41. An apparatus according to claim 40 wherein the RF signal includes a desired RF signal an undesired RF signal, the apparatus further comprising:

a received signal strength indication (RSSI) estimator for estimating the RSSI of the received signal; and

a RSSI compensator for compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

42. An apparatus according to claim 40 further comprising:

a limiter for limiting the gain control signal between a maximum value and a minimum value.

43. An apparatus according to claim 40 wherein the RF signal includes a desired RF signal and an undesired RF signal, the apparatus flirter comprising:

a limiter for limiting the gain control signal to a maximum value responsive to a received signal strength indication (RSSI) of the desired RF signal.

44. An apparatus according to claim 40 further comprising:

a gain control signal determiner for determining whether the gain control signal is favorable or unfavorable; and

a switch permitting the gain controller to adjust a first gain stage of the radio receiver when the gain control signal is favorable and to adjust a second gain stage of the radio receiver when the gain control signal is unfavorable.

45. A method for optimizing a quality of a received signal in a radio receiver having gain, the method comprising the steps of

receiving a radio frequency (RF) signal to produce the received signal;

determining the quality of the received signal;

comparing a present measurement of the quality of the received signal with a past measurement of the quality of the received signal to produce a first output signal;

comparing a present measurement of the gain with a past measurement of the gain to produce a second output signal; and

determining a gain control signal responsive to the first and second output signals; and

adjusting the gain of the radio receiver responsive to the gain control signal.

46. A method according to claim 45 wherein the received signal includes a desired signal and an undesired signal, and wherein the quality of the received signal further comprises:

a ratio indicative of the desired signal to the received signal.

47. A method according to claim 46 wherein the ratio further comprises:

an energy per chip of the desired signal (Ec) to a total power spectral density of the received signal (Io).

48. A method according to claim 45 further comprising the step of:

demodulating the received signal to produce a demodulated signal;

wherein the step of determining the quality of the received signal further comprises the step of estimating an error rate of the demodulated signal; and

wherein the step of adjusting is performed responsive to the error rate of the demodulated signal.

49. A method according to claim 45 wherein the RF signal includes a desired RF signal and an undesired RF signal, the method further comprising the steps of:

estimating a received signal strength indication (RSSI) of the received signal; and

compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

50. A method according to claim 45 the method further comprising the step of

estimating a received signal strength indication (RSSI) of the received signal;

determining whether the quality of the received signal is favorable or unfavorable; and

determining whether the RSSI of the received signal is favorable or unfavorable;

wherein the step of adjusting is performed when both the quality and the RSSI of the received signal are favorable; and

wherein the step of adjusting is not performed when either the quality or the RSSI of the received signal is unfavorable or both the quality and the RSSI of the received signal are unfavorable.

51. A method according to claim 50 wherein the RF signal includes a desired RE signal and an undesired RF signal, the method further comprising the step of:

compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

52. A method according to claim 45 wherein the step of determining further comprises the steps of:

multiplying the first output signal and the second output signal to produce a multiplied signal;

multiplying the multiplied signal by a predetermined gain control step value to produce a gain control step signal; and

summing the gain control step signal with a present gain control signal to produce a future gain control signal.

53. A method according to claim 45 further comprising the step of:

limiting the gain control signal between a maximum value and a minimum value.

54. A method according to claim 45 wherein the RF signal includes a desired RF signal and an undesired RF signal the method further comprising the step of:

limiting the gain control signal to a maximum value responsive to a received signal strength indication (RSSI) of the desired RF signal.

55. A method according to claim 45 further comprising the step of determining whether the gain control signal is favorable or unfavorable;

adjusting a first gain stage of the radio receiver when the gain control signal is favorable; and

adjusting a second gain stage of the radio receiver when the gain control signal is unfavorable.

56. An apparatus for operating a quality of a received signal in a radio receiver having gain, the apparatus comprising:

a receiver for receiving a radio frequency (RF) signal to produce the received signal;

a signal quality determiner for determining the quality of the received signal;

a first comparator for comparing a present measurement of the quality of the received signal with a past measurement of the quality of the received signal to produce a first output signal;

a second comparator for comparing a present measurement of the gain with a past measurement of the gain to produce a second output signal; and

a gain control signal determiner for determining a gain control signal responsive to the first and second output signals; and

a gain controller for adjusting the gain of the radio receiver responsive to the gain control signal.

57. An apparatus according to claim 56 wherein the received signal includes a desired signal and an undesired signal, and wherein the quality of the received signal further comprises:

a ratio indicative of the desired signal to the received signal.

58. An apparatus according to claim 57 wherein the ratio further comprises:

an energy per chip of the desired signal (Ec) to a total power spectral density of the received signal (Io).

59. An apparatus according to claim 56 further:

a demodulator for demodulating the received signal to produce a demodulated signal;

wherein the signal quality determiner further comprises an error rate estimator for estimating an error rate of the demodulated signal; and

wherein gain controller adjusts the gain of the radio receiver responsive to the error rate of the demodulated signal.

60. An apparatus according to claim 56 wherein the RF signal includes a desired RF signal and an undesired RF signal, the apparatus further comprising:

a received signal strength indication (RSSI) estimator for estimating the RSSI of the received signal; and

a RSSI compensator for compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RE signal.

61. An apparatus according to claim 56 the apparatus further comprising:

a received signal strength indication (RSSI) estimator for estimating the RSSI of the received signal;

a first comparator for determining whether the quality of the received signal is favorable or unfavorable; and

a second comparator for determining whether the RSSI of he received signal is favorable or unfavorable;

wherein the gain controller adjusts the gain of the radio receiver when both the quality and the RSSI of the received signal are favorable; and

wherein the gain controller does not adjust the gain of the radio receiver when either the quality or the RSSI of the received signal is unfavorable or both the quality and the RSSI of the received signal are unfavorable.

62. An apparatus according to claim 61 wherein the RF signal includes a desired RF signal and an undesired RF signal, the apparatus further comprising:

a RSSI compensator for compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

63. An apparatus according to claim 56 wherein the gain control signal determiner further comprises:

a first multiplier for multiplying the first output signal and the second output signal to produce a multiplied signal;

a second multiplier for multiplying the multiplied signal by a predetermined gain control step value to produce a gain control step signal; and

a summer for summing the gain control step signal with a present gain control signal to produce a future gain control signal.

64. An apparatus according to claim 56 wherein the gain controller further comprises:

a limiter for limiting the gain control signal between a maximum value and a minimum value.

65. An apparatus according to claim 56 wherein the RF signal includes a desired RF signal and an undesired RF signal, wherein the gain controller further comprises:

a limiter for limiting the gain control signal to a maximum value responsive to a received signal strength indication (kSSI) of the desired RF signal.

66. An apparatus according to claim 56 wherein the gain controller further comprises:

a gain control signal determiner for determining whether the gain control signal is favorable or unfavorable; and

a switch permitting the gain controller to adjust a first gain stage of the radio receiver when the gain control signal is favorable and to adjust a second gain stage of the radio receiver when the gain control signal is unfavorable.

67. A method for optimizing a quality of a received signal in a radio receiver having gain, the method comprising the steps of:

receiving a radio frequency (RF) signal to produce the received signal;

determining the quality of the received signal;

determining a signal power level of the received signal;

determining a signal power of interfering signals received by the radio receiver which cause intermodulation distortion to be generated within the radio receiver, wherein a signal power level of the interfering signals increases as the gain of the radio receiver increases;

determining a signal power level of thermal noise in the radio receiver, wherein the signal power level of the thermal noise decreases as the gain of the radio receiver decreases; and

continuously steering the gain of the radio receiver responsive to the quality of the received signal to maximize a ratio of the signal power of the received signal to a summation of the signal power level of the interfering signals and the signal power level of the thermal noise thereby optimizing the quality of the received signal.

68. A method according to claim 67 wherein the received signal includes a desired signal and an undesired signal, and wherein the quality of the received signal further comprises:

a ratio indicative of the desired signal to the received signal.

69. A method according to claim 68 wherein the ratio further comprises:

an energy per chip of the desired signal (Ec) to a total power spectral density of the received signal (Io).

70. A method according to claim 67 further comprising the step of demodulating the received signal to produce a demodulated signal;

wherein the step of determining the quality of the received signal filter comprises the step of estimating an error rate of the demodulated signal; and

wherein the step of adjusting is performed responsive to the error rate of the demodulated signal.

71. A method according to claim 67 wherein the RF signal includes a desired RF signal and an undesired RF signal, the method further comprising the steps of;

estimating a received signal strength indication (RSSI) of the received signal; and

compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

72. A method according to claim 67 the method further comprising the step of:

estimating a received signal strength indication (RSSI) of the received signal;

determining whether the quality of the received signal is favorable or unfavorable; and

determining whether the RSSI of the received signal is favorable or unfavorable;

wherein the step of adjusting is performed when both the quality and the RSSI of the received signal are favorable; and

wherein the step of adjusting is not performed when either the quality or the RSSI of the received signal is unfavorable or both the quality and the RSSI of the received signal are unfavorable.

73. A method according to claim 72 wherein the RF signal includes a desired RF signal and an undesired RF signal, the method further comprising the step of:

compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

74. A method according to claim 67 further comprising the step of:

generating a gain control signal responsive to the quality of the received signal;

wherein the step of adjusting is performed responsive to the gain control signal.

75. A method according to claim 74 wherein the step of generating further comprises the steps of:

comparing a present measurement of the quality of the received signal with a past measurement of the quality of the received signal to produce a first output signal;

comparing a present measurement of the gain with a past measurement of the gain to produce a second output signal; and

determining the gain control signal responsive to the fist and second output signals.

76. A method according to claim 75 wherein the step of determining further comprises the steps of,

multiplying the first output signal and the second output signal to produce a multiplied signal;

multiplying the multiplied signal by a predetermined gain control step value to produce a gain control step signal; and

summing the gain control step signal with a present gain control signal to produce a future gain control signal.

77. A method according to claim 74 further comprising the step of:

limiting the gain control signal between a maximum value and a minimum value.

78. A method according to claim 74 wherein the RF signal includes a desired RF signal and an undesired RF signal, the method further comprising the step of:

limiting the gain control signal to a maximum value responsive to a received signal strength indication (RSSI) of the desired RE signal.

79. A method according to claim 74 further comprising the step of:

determining whether the gain control signal is favorable or unfavorable;

adjusting a first gain stage of the radio receiver when the gain control signal is favorable; and

adjusting a second gain stage of the radio receiver when the gain control signal is unfavorable.

80. An apparatus for optimizing a quality of a received signal in a radio receiver having gain, the apparatus comprising:

a receiver for receiving a radio frequency (RF) signal to produce the received signal;

a signal quality determiner for determining the quality of the received signal; and

a gain controller for continuously steering the gain of the radio receiver responsive to the quality of the received signal to maximize a ratio of a signal power of the received signal to a summation of a signal power level of interfering signals received by the radio receiver and a signal power level of thermal noise in the radio receiver thereby optimizing the quality of the received signal, wherein the interfering signals received by the radio receiver cause intermodulation distortion to be generated within the radio receiver, wherein the signal power level of the interfering signals increases as the gain of the radio receiver increases and wherein the signal power level of the thermal noise decreases as the gain of the radio receiver decreases.

81. An apparatus according to claim 80 wherein the received signal includes a desired signal and an undesired signal, and wherein the quality of the received signal further comprises:

a ratio indicative of the desired signal to the received signal.

82. An apparatus according to claim 81 wherein the ratio further comprises:

an energy per chip of the desired signal (Ec) to a total power spectral density of the received signal (Io).

83. An apparatus according to claim 80 further:

a demodulator for demodulating the received signal to produce a demodulated signal;

wherein the signal quality determiner further comprises an error rate estimator for estimating an error rate of the demodulated signal; and

wherein gain controller adjusts the gain of the radio receiver responsive to the error rate of the demodulated signal.

84. An apparatus according to claim 80 wherein the R signal includes a desired RF signal and an undesired RF signal, the apparatus further comprising:

a received signal strength indication (RSSI) estimator for estimating the RSSI of the received signal; and

a RSSI compensator for compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

85. An apparatus according to claim 80 the apparatus further comprising:

a received signal strength indication (RSSI) estimator for estimating the RSSI of the received signal;

a first comparator for determining whether the quality of the received signal is favorable or unfavorable; and

a second comparator for determining whether the RSSI of the received signal is favorable or unfavorable;

wherein the gain controller adjusts the gain of the radio receiver when both the quality and the RSSI of the received signal are favorable; and

wherein the gain controller does not adjust the gain of the radio receiver when either the quality or the RSSI of the received signal is unfavorable or both the quality and the RSSI of the received signal are unfavorable.

86. An apparatus according to claim 85 wherein the RF signal includes a desired RF signal and an undesired RF signal, the apparatus further comprising:

a RSSI compensator for compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RE signal.

87. An apparatus according to claim 80:

wherein the gain controller generates a gain control signal responsive to the quality of the received signal; and

wherein the gain controller adjusts the gain of the radio receiver responsive to the gain control signal.

88. An apparatus according to claim 87 wherein the gain controller further comprises:

a first comparator for comparing a present measurement of the quality of the received signal with a past measurement of the quality of the received signal to produce a first output signal;

a second comparator for comparing a present measurement of the gain with a past measurement of the gain to produce a second output signal; and

a gain control signal determiner for determining the gain control signal responsive to the first and second output signals.

89. An apparatus according to claim 88 wherein the gain control signal determiner further comprises:

a first multiplier for multiplying the first output signal and the second output signal to produce a multiplied signal;

a second multiplier for multiplying the multiplied signal by a predetermined gain control step value to produce a gain control step signal; and

a summer for summing the gain control step signal with a present gain control signal to produce a future gain control signal.

90. An apparatus according to claim 87 wherein the gain controller further comprises:

a limiter for limiting the gain control signal between a maximum value and a minimum value.

91. An apparatus according to claim 87 wherein the RF signal includes a desired RF signal and an undesired RF signal, wherein the gain controller further comprises:

a limiter for limiting the gain control signal to a maximum value responsive to a received signal strength indication (RSSI) of the desired RP signal.

92. An apparatus according to claim 87 wherein the gain controller further comprises:

a gain control signal determiner for determining whether the gain control signal is favorable or unfavorable; and

a switch permitting the gain controller to adjust a first gain stage of the radio receiver when the gain control signal is favorable and to adjust a second gain stage of the radio receiver when the gain control signal is unfavorable.

93. A method for optimizing a quality of a received signal in a direct sequence--code division multiple access (DS-CDMA) radio receiver having gain, the method comprising the steps of:

receiving a radio frequency (RF) signal to produce the received signal, wherein the received signal includes a desired signal and an undesired signal;

determining the quality of the received signal, wherein the quality of the received signal further comprises a ratio indicative of the desired signal to the received signal, wherein the ratio further comprises an energy per chip of the desired signal (Ec) to a total power spectral density of the received signal (lo), wherein the ratio provides an indication of whether interfering signals are received by the DS-CDMA radio receiver which cause intermodulation distortion to be generated within the radio receiver; and

decreasing the gain of the radio receiver when interfering signals are determined to be received to increase the linearity of the DS-CDMA radio receiver which reduces the intermodulation distortion thereby improving the quality of the received signal; and

increasing the gain of the radio receiver when interfering signals are determined not to be received to decrease the linearity of the DS-CDMA radio receiver thereby improving the quality of the received signal.

94. A method according to claim 93 wherein the step of adjusting farther comprises the step of continuously steering the gain of the radio receiver responsive to the quality of the received signal.

95. A method according to claim 93 further comprising the step of:

demodulating the received signal to produce a demodulated signal;

wherein the step of determining the quality of the received signal further comprises the step of estimating an error rate of the demodulated signal; and

wherein the step of adjusting is performed responsive to the error rate of the demodulated signal.

96. A method according to claim 93 wherein the RF signal includes a desired RF signal and an undesired RF signal, the method filter comprising the steps of:

estimating a received signal strength indication (RSSI) of the received signal; and

compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

97. A method according to claim 93 the method further comprising the step of:

estimating a received signal strength indication (RSSI) of the received signal;

determining whether the quality of the received signal is favorable or unfavorable; and

determine whether the RSSI of the received signal is favorable or unfavorable;

wherein the step of adjusting is performed when both the quality and the RSSI of the received signal are favorable; and

wherein the step of adjusting is not performed when either the quality or the RSSI of the received signal is unfavorable or both the quality and the RSSI of the received signal are unfavorable.

98. A method according to claim 97 further comprising the step of:

compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

99. A method according to claim 93 further comprising the step of:

generating a gain control signal responsive to the quality of the received signal;

wherein the step of adjusting is performed responsive to the gain control signal.

100. A method according to claim 99 wherein the step of generating further comprises the steps of:

comparing a present measurement of the quality of the received signal with a past measurement of the quality of the received signal to produce a first output signal;

comparing a present measurement of the gain with a past measurement of the gain to produce a second output signal; and

determining the gain control signal responsive to the first and second output signals.

101. A method according to claim 100 wherein the step of determining further comprises the steps of:

multiplying the first output signal and the second output signal to produce a multiplied signal;

multiplying the multiplied signal by a predetermined gain control step value to produce a gain control step signal; and

summing the gain control step signal with a present gain control signal to produce a further gain control signal.

102. A method according to claim 99 fibber comprising the step of:

limiting the gain control signal between a maximum value and a minimum value.

103. A method according to claim 99 wherein the RF signal includes a desired RF signal and an undesired RF signal, the method further comprising the step of:

limiting the gain control signal to a maximum value responsive to a received signal strength indication (RSSI) of the desired RF signal.

104. A method according to claim 99 further comprising the step of:

determining whether the gain control signal is favorable or unfavorable;

adjusting a first gain stage of the radio receiver when the gain control signal is favorable; and

adjusting a second gain stage of the radio receiver when the gain control signal is unfavorable.

105. An apparatus for optimizing a quality of a received signal in a direct sequence--code division multiple access (DS-CDMA) radio receiver having gain, the apparatus comprising:

a receiver for receiving a radio frequency (RF) signal to produce the received signal, wherein the received signal includes a desired signal and an undesired signal;

a signal quality determiner for determining the quality of the received signal, wherein the quality of the received signal further comprises a ratio indicative of the desired signal to the received signal, wherein the ratio further comprises an energy per chip of the desired signal (Ec) to a total power spectral density of the received signal (Io), wherein the ratio provides and indication of whether interfering signals are received by the DS-CDMA radio receiver which cause intermodulation distortion to be generated within the radio receiver; and

a gain controller for improving the quality of the received signal by decreasing the gain of the radio receiver when interfering signals are determined to be received to increase the linearity of the DS-CDMA radio receiver which reduces the intermodulation distortion and by increasing the gain of the radio receiver when interfering signals are determined not to be received to decrease the linearity of the DS-CDMA radio receiver.

106. An apparatus according to claim 105 wherein the gain controller adjusts the gain of the radio receiver by continuously steering the gain of the radio receiver responsive to the quality of the received signal.

107. An apparatus according to claim 105 further comprising:

a demodulator for demodulating the received signal to produce a demodulated signal;

wherein the signal quality determiner further comprises an error rate estimator for estimating an error rate of the demodulated signal; and

wherein gain controller adjusts the gain of the radio receiver responsive to the error rate of the demodulated signal.

108. An apparatus according to claim 105 wherein the RF signal includes a desired RF signal and an undesired RF signal, the apparatus further comprising:

a received signal strength indication (RSSI) estimator for estimating the RSSI of the received signal; and

a RSSI compensator for compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

109. An apparatus according to claim 105 the apparatus further comprising:

a received signal strength indication (RSSI) estimator for estimating the RSSI of the received signal;

a first comparator for determining whether the quality of the received signal is favorable or unfavorable, and a second comparator for determining whether the PSSI of the received signal is favorable or unfavorable;

wherein the gain controller adjusts the gain of the radio receiver when both the qualify and the RSSI of the received signal are favorable; and

wherein the gain controller does not adjust the gain of the radio receiver when either the quality or the RSSI of the received signal is unfavorable or both the quality and the RSSI of the received signal are unfavorable.

110. An apparatus according to claim 109 further comprising:

a RSSI compensator for compensating the RSSI of the received signal responsive to the gain of the radio receiver to produce a compensated RSSI of the received signal indicative of the RSSI of the desired RF signal.

111. An apparatus according to claim 105:

wherein the gain controller generates a gain control signal responsive to the quality of the received signal; and

wherein the gain controller adjusts the gain of the radio receiver responsive to the gain control signal.

112. An apparatus according to claim 111 wherein the gain controller further comprises:

a first comparator for comparing a present measurement of the quality of the received signal with a past measurement of the quality of the received signal to produce a first output signal;

a second comparator for comparing a present measurement of the gain with a past measurement of the gain to produce a second output signal; and

a gain control signal determiner for determining the gain control signal responsive to the first and second output signals.

113. An apparatus according to claim 112 wherein the gain control signal determiner further comprises:

a first multiplier for multiplying the first output signal and the second output signal to produce a multiplied signal;

a second multiplier for multiplying the multiplied signal by a predetermined gain control step value to produce a gain control step signal; and

a summer for summing the gain control step signal with a present gain control signal to produce a future gain control signal.

114. An apparatus according to claim 112 wherein the gain controller further comprises:

a limiter for limiting the gain control signal between a maximum value and a minimum value.

115. An apparatus according to claim 112 wherein the RF signal includes a desired RF signal and an undesired RE signal, wherein the gain controller further comprises:

a limiter for limiting the gain control signal to a maximum value responsive to a received signal strength indication (RSSI) of the desired RE signal.

116. An apparatus according to claim 111 wherein the gain controller further comprises:

a gain control signal determiner for determining whether the gain control signal is favorable or unfavorable; and

a switch permitting the gain controller to adjust a first gain stage of the radio receiver when the gain control signal is favorable and to adjust a second gain stage of the radio receiver when the gain control signal is unfavorable.