Nonlinear distortion compensating device

• US 20030228856A1
• Filed: 04/09/2003
• Published: 12/11/2003
• Est. Priority Date: 04/10/2002
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Corporation of America (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Takabayashi, Shinichiro, Murakami, Yutaka, Orihashi, Masayuki, Matsuoka, Akihiko
• Granted Patent: US 7,280,611 B2
• Time in Patent Office: Days
• US Class Current: 455/226.1
• CPC Class Codes: H03F 1/3247 using feedback acting on predistortion circuits H03F1/3264 takes precedence
• CPC Class Codes: H03F 1/3282 Acting on the phase and the amplitude of the input signal
• CPC Class Codes: H03F 1/34 Negative-feedback-circuit arrangements with or without positive feedback H03F1/02 - H03F1/30, H03F1/38 - H03F1/50, H03F3/50 take precedence ; for rejection of common mode signals H03F3/45479
• CPC Class Codes: H03F 2201/3233 Adaptive predistortion using lookup table, e.g. memory, RAM, ROM, LUT, to generate the predistortion
• CPC Class Codes: H03F 3/24 of transmitter output stages
• CPC Class Codes: H04B 2001/0433 with linearisation using feedback
• CPC Class Codes: H04B 7/15535 Control of relay amplifier gain amplifier gain control in general H03G3/00; gain control reducing self - or loop interference H04B7/15578
• CPC Class Codes: H04L 27/368 adaptive predistortion

Abstract

A nonlinear distortion compensating device splits its operation into two processes. One is a compensation & amplification process for providing a receipt signal with a distortion compensating calculation and amplification before outputting the signal with phase and amplitude compensated. The other is an environmentally adapting process for modulating the signal demodulated from the input signal. Then in this process, a distortion estimating updater estimates a distortion amount using the modulated signal and a feed back signal of parts of the output supplied from the distortion compensating calculator, and updates a distortion compensating coefficient stored in the distortion compensating calculator.

Claims

1. A nonlinear distortion compensating device comprising:

a distortion compensating calculator for receiving an input signal and a distortion compensating coefficient, and outputting the input signal with phase distortion and amplitude distortion compensated;

a demodulator for demodulating the input signal;

a modulator for modulating again the demodulated signal; and

a distortion estimating updater for feeding back parts of the signal output from the distortion compensating calculator, estimating a distortion amount from the fed back signal and the signal re-modulated by the modulator, and updating the distortion compensating coefficient stored in the calculator.

2. The nonlinear distortion compensating device of claim 1 further comprising:

a frequency converter for converting the fed back signal into an IF frequency that is lower than a carrier frequency, wherein an IF fed back signal converted by the converter is input to the distortion estimating updater.

3. The nonlinear distortion compensating device of claim 1, wherein the distortion compensating calculator includes:

a first frequency converter for converting an input RF signal into an IF signal;

a buffer for holding the IF signal temporarily;

a compensator for calculating distortion compensation using the signal supplied from the buffer and the distortion compensating coefficient;

a second frequency converter for converting the IF signal with its distortion compensated into the RF signal; and

a timing controller for determining an output timing of a delayed IF signal following a signal supplied from the buffer.

4. The nonlinear distortion compensating device of claim 1, wherein the demodulator demodulates and detects the input signal, and the modulator modulates the signal following a modulation method of the input signal based on the detection result.

5. The nonlinear distortion compensating device of claim 1 further comprising:

a separator for separating the input signal into at least two signals in response to a frequency of the input signal;

a distortion compensating calculator for estimating and compensating a distortion amount of the separated signal;

an amplifier for amplifying the signal with the distortion compensated;

wherein the distortion compensating calculator and the amplifier are prepared respectively for respective separated signals, and

a combiner for combining signals supplied from the respective amplifiers.

6. The nonlinear distortion compensating device of claim 1 further comprising a separator for separating the input signal into at least two signals in response to timing of time-sharing the input signal.

7. The nonlinear distortion compensating device of claim 1 further comprising:

a channel controller for updating the compensating coefficient of the distortion compensating calculator with respect to a signal of a channel designated among the input signal.

8. The nonlinear distortion compensating device of claim 1 further comprising a channel controller for updating contents stored in an input distortion compensating calculator and an element distortion compensating calculator.

9. A nonlinear distortion compensating device comprising:

a distortion compensating calculator for receiving an input signal and a distortion compensating coefficient, and outputting the input signal with phase distortion and amplitude distortion compensated;

a first quadrature demodulator for converting the input signal into an input base-band signal;

,

a second quadrature demodulator for feeding back parts of the signal output from the distortion compensating calculator, and converting the fed back signal into a feedback base-band signal; and

a distortion estimating updater for estimating a distortion amount from the input base-band signal and the feedback base-band signal, and updating the distortion compensating coefficient stored in the calculator.

10. The nonlinear distortion compensating device of claim 9 further comprising:

a separator for separating the input signal into at least two signals in response to a frequency of the input signal;

a distortion compensating calculator for estimating and compensating for a distortion amount of the separated signal;

an amplifier for amplifying the signal with the distortion compensated;

wherein the distortion compensating calculator and the amplifier are prepared respectively for respective separated signals, and

a combiner for combining signals supplied from the respective amplifiers.

11. The nonlinear distortion compensating device of claim 9 further comprising a separator for separating the input signal into at least two signals in response to timing of time-sharing the input signal.

12. The nonlinear distortion compensating device of claim 9 further comprising:

a channel controller for updating the compensating coefficient stored in the distortion compensating calculator, the coefficient being assigned to a signal of a channel selected from the input signal.

13. The nonlinear distortion compensating device of claim 9 further comprising a channel controller for updating contents stored in an input distortion compensating calculator and an element distortion compensating calculator.

14. A nonlinear distortion compensating device comprising:

a distortion compensating calculator for receiving an input signal and a distortion compensating coefficient, and outputting the input signal with phase distortion and amplitude distortion compensated;

a demodulator for demodulating the input signal;

a base-band demodulator for demodulating the demodulated signal into a reference base-band signal;

a quadrature demodulator for feeding back parts of the signal output from the distortion compensating calculator, and converting the fed back signal into a feedback base-band signal; and

a distortion estimating updater for estimating a distortion amount from the reference base-band signal and the feedback base-band signal, and updating the distortion compensating coefficient stored in the calculator.

15. The nonlinear distortion compensating device of claim 14, wherein the demodulator demodulates and detects the input signal, and the modulator modulates the signal following a modulation method of the input signal based on the detection result.

16. The nonlinear distortion compensating device of claim 14 further comprising:

a separator for separating the input signal into at least two signals in response to a frequency of the input signal;

a distortion compensating calculator for estimating and compensating for a distortion amount of the separated signal;

an amplifier for amplifying the signal with the distortion compensated;

wherein the distortion compensating calculator and the amplifier are prepared respectively for respective separated signals, and

a combiner for combining signals supplied from the respective amplifiers.

17. The nonlinear distortion compensating device of claim 14 further comprising a separator for separating the input signal into at least two signals in response to timing of time-sharing the input signal.

18. The nonlinear distortion compensating device of claim 14 further comprising:

a channel controller for updating the compensating coefficient stored in the distortion compensating calculator, the coefficient being assigned to a signal of a channel selected from the input signal.

19. The nonlinear distortion compensating device of claim 14 further comprising a channel controller for updating contents stored in an input distortion compensating calculator and an element distortion compensating calculator.

20. A nonlinear distortion compensating device comprising:

a distortion compensating calculator for receiving an input signal and a distortion compensating coefficient, and outputting the input signal with phase distortion and amplitude distortion compensated;

a demodulator for demodulating the input signal;

a base-band demodulator for demodulating the demodulated signal into a reference -base-band signal;

a quadrature demodulator for feeding back parts of the signal output from the distortion compensating calculator, and converting the fed back signal into a feedback base-band signal; and

a distortion estimating updater for estimating a distortion amount from the reference base-band signal, the feedback base-band signal and frequency-error information, and updating the distortion compensating coefficient stored in the calculator; and

a frequency estimating controller for estimating a frequency error from the demodulated signal, and controlling respective frequencies of the demodulator and the quadroture demodulator.

21. The nonlinear distortion compensating device of claim 20, wherein the demodulator demodulates and detects the input signal, and the modulator modulates the signal following a modulation method of the input signal based on the detection result.

22. The nonlinear distortion compensating device of claim 20 further comprising:

a separator for separating the input signal into at least two signals in response to a frequency of the input signal;

a distortion compensating calculator for estimating and compensating for a distortion amount of the separated signal;

an amplifier for amplifying the signal with the distortion compensated;

wherein the distortion compensating calculator and the amplifier are prepared respectively for respective separated signals, and

a combiner for combining signals supplied from the respective amplifiers.

23. The nonlinear distortion compensating device of claim 20 further comprising a separator for separating the input signal into at least two signals in response to timing of time-sharing the input signal.

24. The nonlinear distortion compensating device of claim 20 further comprising:

a channel controller for updating the compensating coefficient stored in the distortion compensating calculator, the coefficient being assigned to a signal of a channel selected from the input signal.

25. The nonlinear distortion compensating device of claim 20 further comprising a channel controller for updating contents stored in an input distortion compensating calculator and an element distortion compensating calculator.

26. A nonlinear distortion compensating device comprising:

a propagation distortion compensator for estimating propagation distortion from an input signal, and compensating the estimated propagation distortion; and

an element distortion compensator for estimating element distortion from a fed back signal which is formed by feeding back parts of an output signal, and a signal with the propagation distortion compensated, and outputting an element distortion compensated signal of which element distortion has been compensated.

27. The nonlinear distortion compensating device of claim 26 further comprising:

a separator for separating the input signal into at least two signals in response to a frequency of the input signal;

a distortion compensating calculator for estimating and compensating a distortion amount of the separated signal;

an amplifier for amplifying the signal with the distortion compensated;

wherein the distortion compensating calculator and the amplifier are prepared respectively for respective separated signals, and

a combiner for combining signals supplied from the respective amplifiers.

28. The nonlinear distortion compensating device of claim 26 further comprising a separator for separating the input signal into at least two signals in response to timing of time-sharing the input signal.

29. The nonlinear distortion compensating device of claim 26 further comprising:

a channel controller for updating the compensating coefficient of the distortion compensating calculator, the coefficient being assigned to a signal of a channel selected from the input signal.

30. The nonlinear distortion compensating device of claim 26 further comprising a channel controller for updating contents stored in an input distortion compensating calculator and the element distortion compensating calculator.

31. A nonlinear distortion compensating device comprising:

a diffraction remover for estimating an amount of diffraction of an input signal and an output signal, and removing a diffraction component; and

an element distortion compensator for estimating distortion of elements from a fed back signal which is formed by feeding back parts of the output signal, and the diffraction removed signal, and outputting element distortion compensated signal.

32. The nonlinear distortion compensating device of claim 31 further comprising:

a separator for separating the input signal into at least two signals in response to a frequency of the input signal;

an input distortion compensator for estimating a diffraction amount or propagation distortion, and compensating for the estimated diffraction or propagation distortion;

a distortion compensating calculator for estimating and compensating for a distortion amount of the separated signal;

an amplifier for amplifying the signal with the distortion compensated;

wherein the input distortion compensator, the distortion compensating calculator and the amplifier are prepared respectively for respective separated signals, and

a combiner for combining signals supplied from the respective amplifiers.

33. The nonlinear distortion compensating device of claim 31 further comprising a separator for separating the input signal into at least two signals in response to timing of time-sharing the input signal.

34. The nonlinear distortion compensating device of claim 31 further comprising:

a channel controller for updating the compensating coefficient stored in the distortion compensating calculator, the coefficient being assigned to a signal of a channel selected from the input signal.

35. The nonlinear distortion compensating device of claim 31 further comprising a channel controller for updating contents stored in an input distortion compensating calculator and the element distortion compensating calculator.

36. A nonlinear distortion compensating device comprising:

an input distortion compensator including;

a propagation distortion compensator for estimating propagation distortion from an input signal, and compensating for the estimated propagation distortion;

a diffraction remover for estimating an amount of diffraction of the input signal and an output signal, and removing a diffraction component; and

an element distortion compensator for estimating element distortion from a fed back signal, which is formed by feeding back parts of the output signal, and a signal with the propagation distortion compensated, and outputting an element distortion compensated signal.

37. The nonlinear distortion compensating device of claim 36 further comprising:

a base-band modulator for outputting a reference base-band signal formed by providing the input signal with quadrature demodulation, and a fed back base-band signal formed by providing the feedback signal with quadrature demodulation into the element distortion compensator.

38. The nonlinear distortion compensating device of claim 37, wherein the reference side-band signal is obtained by demodulating, or modulating the input signal.

39. The nonlinear distortion compensating device of claim 36 further comprising:

a separator for separating the input signal into at least two signals in response to a frequency of the input signal;

an input distortion compensator for estimating a diffraction amount or propagation distortion, and compensating for the estimated diffraction or propagation distortion;

a distortion compensating calculator for estimating and compensating for a distortion amount of the separated signal;

an amplifier for amplifying the signal with the distortion compensated;

wherein the input distortion compensator, the distortion compensating calculator and the amplifier are prepared respectively for respective separated signals, and

a combiner for combining signals supplied from the respective amplifiers.

40. The nonlinear distortion compensating device of claim 36 further comprising a separator for separating the input signal into at least two signals in response to timing of time-sharing the input signal.

41. The nonlinear distortion compensating device of claim 36 further comprising:

a channel controller for updating the compensating coefficient stored in the distortion compensating calculator, the coefficient being assigned to a signal of a channel selected from the input signal.

42. The nonlinear distortion compensating device of claim 36 further comprising a channel controller for updating contents stored in the input distortion compensating calculator and the element distortion compensating calculator.

43. A nonlinear distortion compensating device comprising:

a demodulator for demodulating an input signal, and outputting the demodulated signal;

a propagation distortion compensator for estimating propagation distortion from the demodulated signal and the input signal, and outputting a propagation distortion compensated signal; and

an element distortion compensator for receiving an output from the propagation distortion compensator, estimating element distortion from a fed back signal formed by feeding back parts of an output signal, the demodulated signal and the propagation distortion compensated signal, and outputting the element distortion compensated signal.

44. The nonlinear distortion compensating device of claim 43 further comprising:

a separator for separating the input signal into at least two signals in response to a frequency of the input signal;

an input distortion compensator for estimating a diffraction amount or propagation distortion, and compensating for the estimated diffraction or propagation distortion;

a distortion compensating calculator for estimating and compensating for a distortion amount of the separated signal;

an amplifier for amplifying the signal with the distortion compensated;

wherein the input distortion compensator, the distortion compensating calculator and the amplifier are prepared respectively for respective separated signals, and

a combiner for combining signals supplied from the respective amplifiers.

45. The nonlinear distortion compensating device of claim 43 further comprising a separator for separating the input signal into at least two signals in response to timing of time-sharing the input signal.

46. The nonlinear distortion compensating device of claim 43 further comprising:

a channel controller for updating the compensating coefficient stored in the distortion compensating calculator, the coefficient being assigned to a signal of a channel selected from the input signal.

47. The nonlinear distortion compensating device of claim 43 further comprising a channel controller for updating contents stored in an input distortion compensating calculator and the element distortion compensating calculator.

48. A nonlinear distortion compensating device comprising:

a demodulator for demodulating an input signal, and outputting the demodulated signal;

a diffraction remover for estimating an amount of diffraction of the input signal and an output signal, and removing a diffraction component; and

an element distortion compensator for receiving an output from the diffraction remover, estimating element distortion from a fed back signal formed by feeding back parts of an output signal, the demodulated signal and the diffraction removed signal, and outputting the element distortion compensated signal.

49. The nonlinear distortion compensating device of claim 48 further comprising:

a separator for separating the input signal into at least two signals in response to a frequency of the input signal;

an input distortion compensator for estimating a diffraction amount or propagation distortion, and compensating for the estimated diffraction or propagation distortion;

a distortion compensating calculator for estimating and compensating for a distortion amount of the separated signal;

an amplifier for amplifying the signal with the distortion compensated;

wherein the input distortion compensator, the distortion compensating calculator and the amplifier are prepared respectively for respective separated signals, and

a combiner for combining signals supplied from the respective amplifiers.

50. The nonlinear distortion compensating device of claim 48 further comprising a separator for separating the input signal into at least two signals in response to timing of time-sharing the input signal.

51. The nonlinear distortion compensating device of claim 48 further comprising:

a channel controller for updating the compensating coefficient of the distortion compensating calculator, the coefficient being assigned to a signal of a channel selected from the input signal.

52. The nonlinear distortion compensating device of claim 48 further comprising a channel controller for updating contents stored in an input distortion compensating calculator and the element distortion compensating calculator.

53. A nonlinear distortion compensating device comprising:

a demodulator for demodulating an input signal, and outputting the demodulated signal;

an input distortion compensator for estimating propagation distortion or a diffraction amount of an output signal from the demodulated signal and the input signal, and outputting an input distortion compensated signal with the estimated propagation distortion compensated or the estimated diffraction component removed; and

an element distortion compensator for receiving an output from the propagation distortion compensator, estimating element distortion from a fed back signal formed by feeding back parts of an output signal, the demodulated signal and the input distortion compensated signal, and outputting the element distortion compensated signal.

54. The nonlinear distortion compensating device of claim 53 further comprising:

a separator for separating the input signal into at least two signals in response to a frequency of the input signal;

an input distortion compensator for estimating a diffraction amount or propagation distortion, and compensating for the estimated diffraction or propagation distortion;

a distortion compensating calculator for estimating and compensating for a distortion amount of the separated signal;

an amplifier for amplifying the signal with the distortion compensated;

wherein the input distortion compensator, the distortion compensating calculator and the amplifier are prepared respectively for respective separated signals, and

a combiner for combining signals supplied from the respective amplifiers.

55. The nonlinear distortion compensating device of claim 53 further comprising a separator for separating the input signal into at least two signals in response to timing of time-sharing the input signal.

56. The nonlinear distortion compensating device of claim 53 further comprising:

a channel controller for updating the compensating coefficient stored in the distortion compensating calculator, the distortion being assigned to a signal of a channel selected from the input signal.

57. The nonlinear distortion compensating device of claim 53 further comprising a channel controller for updating contents stored in the input distortion compensating calculator and the element distortion compensating calculator.

58. A nonlinear distortion compensating device comprising:

a demodulator for demodulating an input signal and outputting the demodulated signal;

an element distortion compensator for estimating element distortion from a fed back demodulated signal formed by feeding back parts of an output signal and demodulating the fed back signal following a reference frequency, the demodulated signal and the input signal, and outputting an element distortion compensated signal;

a timing controller for controlling a timing of updating an element distortion coefficient based on a reference time supplied by the demodulator; and

a frequency controller for estimating a frequency error between the input signal and the demodulator output, and controlling a reference frequency of the demodulator and the element distortion compensator.

59. The nonlinear distortion compensating device of claim 58 further comprising:

a separator for separating the input signal into at least two signals in response to a frequency of the input signal;

an input distortion compensator for estimating a diffraction amount or propagation distortion, and compensating for the estimated diffraction or propagation distortion;

a distortion compensating calculator for estimating and compensating for a distortion amount of the separated signal;

an amplifier for amplifying the signal with the distortion compensated;

wherein the input distortion compensator, the distortion compensating calculator and the amplifier are prepared respectively for respective separated signals, and

a combiner for combining signals supplied from the respective amplifiers.

60. The nonlinear distortion compensating device of claim 58 further comprising a separator for separating the input signal into at least two signals in response to timing of time-sharing the input signal.

61. The nonlinear distortion compensating device of claim 58 further comprising:

a channel controller for updating the compensating coefficient stored in the distortion compensating calculator, the coefficient being assigned to a signal of a channel selected from the input signal.

62. The nonlinear distortion compensating device of claim 58 further comprising a channel controller for updating contents stored in an input distortion compensating calculator and the distortion compensating calculator.

63. A nonlinear distortion compensating device comprising:

a distortion compensating calculator for receiving an input signal with an amplitude limited and an element distortion compensating coefficient, and outputting an element distortion compensated signal;

a demodulator for demodulating the input signal;

a base-band modulator for modulating the demodulated signal into a reference base-band signal;

a signal amplitude limiter for limiting an amplitude of the input signal and the reference base-band signal, and outputting an amplitude limited input signal and an amplitude limited reference base-band signal;

a quadrature demodulator for feeding back parts of an amplified signal, and converting the fed back signal into a feeback base-band signal; and

a distortion estimating updater for estimating a distortion amount from the limited amplitude reference base-band signal and the feed back base-band signal, and updating the element distortion compensating coefficient stored in the distortion compensating calculator.

64. The nonlinear distortion compensating device of claim 63 further comprising:

a separator for separating the input signal into at least two signals in response to a frequency of the input signal;

an input distortion compensator for estimating a diffraction amount or propagation distortion, and compensating for the estimated diffraction or propagation distortion;

a distortion compensating calculator for estimating and compensating for a distortion amount of the separated signal;

an amplifier for amplifying the signal with the distortion compensated;

wherein the input distortion compensator, the distortion compensating calculator and the amplifier are prepared respectively for respective separated signals, and

a combiner for combining signals supplied from the respective amplifiers.

65. The nonlinear distortion compensating device of claim 63 further comprising a separator for separating the input signal into at least two signals in response to timing of time-sharing the input signal.

66. The nonlinear distortion compensating device of claim 63 further comprising:

a channel controller for updating the compensating coefficient stored in the distortion compensating calculator, the coefficient being assigned to a signal of a channel selected from the input signal.

67. The nonlinear distortion compensating device of claim 63 further comprising a channel controller for updating contents stored in an input distortion compensating calculator and an element distortion compensating calculator.

68. A nonlinear distortion compensating device comprising:

a demodulator for demodulating an input signal and outputting the demodulated signal;

an input distortion compensator for estimating propagation distortion or a diffraction amount of an output signal from the demodulated signal and the input signal, and outputting an input distortion compensated signal with the propagation distortion compensated or the diffraction component removed;

a quadrature demodulator for demodulating a signal formed by feeding back parts of an output signal, and outputting a fed back signal;

a modulator for producing a reference signal from the demodulated signal;

an amplitude limiter for limiting an amplitude of the reference signal or an amplitude of the input distortion compensated signal, and outputting an amplitude limited reference signal or an amplitude limited input distortion compensated signal;

an element distortion compensating calculator for calculating a distortion amount of an element corresponding to the amplitude limited input distortion compensated signal, and outputting an element distortion compensated signal; and

an element distortion estimating updater for estimating a distortion amount from the amplitude limited reference signal, the fed back signal and a distortion amount calculated by the element distortion compensating calculator.

69. The nonlinear distortion compensating device of claim 68 further comprising:

a separator for separating the input signal into at least two signals in response to a frequency of the input signal;

an input distortion compensator for estimating a diffraction amount or propagation distortion, and-compensating for the estimated diffraction or propagation distortion;

a distortion compensating calculator for estimating and compensating for a distortion amount of the separated signal;

an amplifier for amplifying the signal with the distortion compensated;

wherein the input distortion compensator, the distortion compensating calculator and the amplifier are prepared respectively for respective separated signals, and

a combiner for combining signals supplied from the respective amplifiers.

70. The nonlinear distortion compensating device of claim 68 further comprising a separator for separating the input signal into at least two signals in response to timing of time-sharing the input signal.

71. The nonlinear distortion compensating device of claim 68 further comprising:

a channel controller for updating the compensating coefficient stored in the distortion compensating calculator, the distortion being assigned to a signal of a channel selected from the input signal.

72. The nonlinear distortion compensating device of claim 68 further comprising a channel controller for updating contents stored in an input distortion compensating calculator and the element distortion compensating calculator.

73. A nonlinear distortion compensating device comprising:

a first signal system for calculating a distortion amount of an element from an input signal; and

a second signal system for separating the input signal into parts and an output signal into parts, and estimating an amount of distortion for the first signal system to calculate, or updating distortion.