System and method for radio signal reconstruction using signal processor

• US 8,170,519 B2
• Filed: 12/09/2010
• Issued: 05/01/2012
• Est. Priority Date: 02/05/1996
• Status: Expired due to Fees

• Current Assignee: American Radio LLC
• Original Assignee: American Radio LLC
• Inventors: Hotto, Robert
• Primary Examiner(s): Sobutka, Philip
• Application Number:
  US12/964,215
• Publication Number:
  US 20110103531A1
• Time in Patent Office: 509 Days
• Field of Search: None
• US Class Current: 455/280
• CPC Class Codes: H03D 7/16 Multiple-frequency-changing
• CPC Class Codes: H04B 1/10 Means associated with receiver for limiting or suppressing noise or interference
• CPC Class Codes: H04B 1/123 using adaptive balancing or compensation means adaptive filter circuits and algorithms H03H
• CPC Class Codes: H04B 1/18 Input circuits, e.g. for coupling to an antenna or a transmission line coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H

Abstract

A waveform reconstruction circuit receives an rf signal from an antenna, digitizes it, and then generates an undistorted reconstructed waveform. The reconstructed waveform can then be conventionally mixed and demodulated to extract useful signal information with enhanced receiver fidelity and sensitivity.

Claims

1. An apparatus comprising:

a converter receiving as input an rf signal that has not been downconverted in the analog domain to IF, the converter outputting a digitized signal representing the rf signal; and

a hardware module electrically connected to the converter, the module being configured with software to decode and extract baseband information from the digitized signal, wherein the module replaces at least one distorted portion of the signal with a replacement portion.

2. An apparatus, comprising:

a reconstruction circuit receiving an analog sinusoidal signal and generating a reconstructed waveform having substantially no distortions therein, wherein the reconstruction circuit includes;

a converter receiving the analog sinusoidal signal that has not been downconverted in the analog domain by the reconstruction circuit and outputting a digitized signal in response; and

a module electrically connected to the converter for outputting the reconstructed waveform in accordance with a predetermined reconstruction paradigm which includes generating the reconstructed waveform using at least portions of the digitized signal.

3. The apparatus of claim 2, wherein the paradigm includes replacing at least one distorted portion of the signal with a replacement portion that is based on at least some undistorted portions of the signal.

4. A device, comprising:

a circuit receiving an analog waveform carried in an optical transmission line, wherein the circuit includes;

an element for receiving the signal prior to any extraction of baseband information therefrom and outputting a non-continuous signal in response;

an element receiving the non-continuous signal and repairing at least a portion of the non-continuous signal prior to the extraction of baseband information from the non-continuous signal; and

at least one module electrically connected to the element receiving the non-continuous signal and in response outputting a baseband waveform.

5. The receiver of claim 4, wherein a reconstruction paradigm is applied to the non-continuous signal, the reconstruction paradigm including replacing at least one distorted portion of the signal with a replacement portion that is based on at least some undistorted portions of the signal.

6. A method, comprising:

converting a continuous signal that has not been downconverted and demodulated in the analog domain into a non-continuous signal, the continuous signal being a carrier for baseband information;

repairing the non-continuous signal prior to completing a downconversion operation;

generating, subsequent to the repairing, a digitized signal from the non-continuous signal; and

extracting the baseband information from the digitized signal without converting the digitized signal to the analog domain.

7. The method of claim 6, wherein the repairing is executed in the RF domain.

8. The method of claim 6, wherein the repairing includes signal reconstruction of distorted portions of the signal using the non-continuous signal.

9. A device, comprising:

a circuit configured to receive an analog waveform carried in an optical transmission line, wherein the circuit includes;

at least a first subcircuit configured to receive the signal prior to any extraction of baseband information therefrom and to output a non-continuous signal in response;

at least a second subcircuit receiving the non-continuous signal, the second subcircuit repairing at least portions of the non-continuous signal; and

at least one processing assembly electrically connected to the second subcircuit to receive the non-continuous signal and in response to output a baseband waveform.

10. The receiver of claim 9, wherein a reconstruction paradigm is applied to the non-continuous signal, the reconstruction paradigm including replacing at least one distorted portion of the signal with a replacement portion that is based on at least some undistorted portions of the signal.

11. A method, comprising:

converting a continuous carrier signal that has not been downconverted and demodulated in the analog domain into a non-continuous signal;

reconstructing the non-continuous signal prior to completing a downconversion operation;

generating, subsequent to the reconstructing, a digitized signal; and

extracting baseband information from the digitized signal without analogizing the digitized signal.

12. The method of claim 11, wherein the repairing is executed in the RF domain.

13. The method of claim 11, wherein the repairing includes signal reconstruction of distorted waveform portions using the non-continuous signal.

14. A method, comprising:

converting a continuous RF signal that has not been downconverted and demodulated in the analog domain into a non-continuous signal, the RF signal being received from a signal path that includes at least one optical transmission line;

reconstructing at least one distorted portion of the non-continuous signal prior to completing a downconversion operation;

generating, subsequent to the processing, a digitized signal; and

extracting baseband information from the digitized signal.

15. The method of claim 14, wherein the reconstructing is effected on the non-continuous signal while still in the RF domain.

16. An article of manufacture, comprising:

a circuit receiving an analog waveform carried in an optical transmission line and conveying baseband information useful for display to a person, wherein the circuit includes;

at least one subcircuit receiving the signal prior to any extraction of baseband information therefrom and outputting a non-continuous signal in response; and

at least one processing assembly electrically connected to the subcircuit and receiving the non-continuous signal and in response outputting a baseband waveform from which baseband information for display is obtained while still in the digital domain, the processing assembly repairing at least one portion of the non-continuous signal.

17. The receiver of claim 16, wherein the processing assembly repairs the at least one portion of the non-continuous signal before rendering the baseband waveform.

18. An apparatus comprising:

a converter receiving as input an rf signal that has not been downconverted and demodulated in the analog domain, the converter outputting a digitized signal representing the rf signal; and

a module electrically connected to the converter, the module being configured to decode and extract baseband information from the digitized signal without requiring the digitized signal to be converted to the analog domain prior to extracting the baseband information therefrom, wherein the module reconstructs irregularities in the digitized signal prior to extracting the baseband information therefrom.

19. The apparatus of claim 18, wherein the module replaces at least one distorted portion of the signal with a replacement portion.

20. The apparatus of claim 18, wherein the apparatus amplifies the rf signal.

21. The apparatus of claim 18, wherein the apparatus filters the rf signal.

22. An electronic assembly comprising:

a receiving circuit receiving as input an rf signal that has not been downconverted by the assembly in the analog domain, the receiving circuit outputting a digitized signal representing the rf signal; and

a module electrically connected to the receiving circuit, the module being configured to decode and extract, in the digital domain, baseband information from the digitized signal, wherein the module reconstructs at least portions of the digitized signal while in the digital domain.

23. The assembly of claim 22, wherein the module replaces at least one distorted portion of the signal with a replacement portion.

24. The assembly of claim 22, wherein the module reconstructs at least portions of the digitized signal while in the digital RF domain.

25. The assembly of claim 22, wherein the assembly filters the rf signal.

26. An electronic assembly comprising:

a receiving circuit receiving as input an rf signal that has not been downconverted by the assembly to an intermediate frequency (IF) from which baseband information is decoded, the receiving circuit outputting a digitized signal representing the rf signal; and

a module electrically connected to the receiving circuit, the module being configured to decode and extract baseband information from the digitized signal while the digitized signal remains in the digital domain, wherein the module reconstructs at least one portion of the signal.

27. The assembly of claim 26, wherein the wherein the module replaces at least one distorted portion of the signal with a replacement portion prior to any downconversion and/or demodulation of the digitized signal by the assembly.

28. The assembly of claim 26, wherein the assembly filters the rf signal.

29. An electronic assembly comprising:

a receiving circuit configured to receive as input an rf signal that has not been downconverted by the assembly to a frequency from which baseband information is decoded, the receiving circuit configured to output a digitized signal representing the rf signal with at least one distorted portion of the digitized signal being corrected; and

a module electrically connected to the receiving circuit, the module being configured to decode and extract baseband information from the digitized signal with the digitized signal remaining in the digital domain.

30. The assembly of claim 29, wherein the module is configured to replace at least one distorted portion of the signal with a replacement portion.

31. The assembly of claim 29, wherein the assembly is configured to amplify the rf signal.

32. The assembly of claim 29, wherein the assembly is configured to filter the rf signal.

33. An electronic assembly comprising:

a receiving circuit configured to receive as input an rf signal that has not been downconverted by the electronic assembly in the analog domain, the receiving circuit configured to output a digitized signal representing the rf signal; and

a module electrically connected to the receiving circuit, the module being configured to decode and extract baseband information from the digitized signal, the digitized signal remaining digitized during extraction of baseband information therefrom, the receiving circuit and/or module reconstructing, in a digital domain, at least one portion of the rf signal as received in the analog domain, prior to any extraction of baseband information from the digitized signal.

34. The assembly of claim 33, wherein the module is configured to replace at least one distorted portion of the signal with a replacement portion.

35. The assembly of claim 33, wherein the assembly is configured to amplify the rf signal.

36. The assembly of claim 33, wherein the assembly is configured to filter the rf signal.

37. An electronic assembly comprising:

a receiving circuit configured for receiving as input an rf signal that has not been downconverted to an intermediate frequency (IF) from which baseband information is decoded, the receiving circuit configured for outputting a digitized signal representing the rf signal; and

a module electrically connected to the receiving circuit, the module being configured to decode and extract baseband information from the digitized signal while the digitized signal remains in the digital domain, wherein the module replaces at least one distorted portion of the signal with a replacement portion.

38. The assembly of claim 37, wherein the module replaces at least one distorted portion of the signal with a replacement portion prior to downconverting the digitized signal from the RF domain.

39. The assembly of claim 37, wherein the assembly amplifies the rf signal.

40. The assembly of claim 37, wherein the assembly filters the rf signal.

41. A receiver, comprising:

an incoming signal port at which an rf signal that has propagated through a transmission medium is received;

a converter downstream of the incoming signal port and receiving an analog signal from downstream of the incoming signal port, the converter outputting a non-analog signal representative of the analog signal; and

a digital processor electrically connected to the converter, the digital processor being configured to extract base band information from the non-analog signal without converting the non-analog signal to the analog domain after first reducing distortion in the digitized signal.

42. The receiver of claim 41, wherein the digital processor is configured to reconstruct at least some distorted portions of the signal being processed, wherein at least one distorted portion is reconstructed by replacing the distorted portion with an undistorted portion.

43. The receiver of claim 41, wherein the converter digitizes the analog signal prior to any demodulation thereof.

44. The receiver of claim 41, further comprising a mixer generating an intermediate frequency (IF) signal based on the non-analog signal, and a demodulator decoding useful information from the IF signal, wherein at least the mixer and demodulator are embodied in the digital processor.

45. The receiver of claim 41, wherein the incoming signal port is coupled to an antenna.

46. A receiver, comprising:

an input;

a converter downstream of the input and receiving an analog signal therefrom, the converter outputting a non-analog signal representative of the analog signal; and

a digital processor electrically connected to the converter, the digital processor being programmed with software to improve the extraction of useful portions of the analog signal that had been corrupted and then to extract base band information from the non-analog signal.

47. The receiver of claim 46, wherein the digital processor is configured to reconstruct at least some distorted portions of the signal being processed, wherein at least one distorted portion is reconstructed by replacing the distorted portion with an undistorted portion.

48. The receiver of claim 46, wherein the converter digitizes the analog signal prior to any demodulation thereof.

49. The receiver of claim 46, further comprising a mixer generating an intermediate frequency (IF) signal based on the non-analog signal, and a demodulator decoding useful information from the IF signal, wherein at least the mixer and demodulator are embodied in the digital processor.

50. The receiver of claim 46, wherein the input is coupled to an antenna.

51. A receiver of wireless voice data, comprising:

a signal input;

an analog to digital converter (ADC) downstream of the signal input and receiving an rf signal having distortions from the signal input and configured to output a digitized signal representative of the rf signal; and

a module electrically connected to the ADC, the module being configured to generate a substantially undistorted reconstructed waveform from the digitized signal and then to extract baseband information from the digitized signal prior to any analogization of the digitized information, the baseband information representing at least in part voice data.

52. The receiver of claim 51, wherein the signal input is connected to an antenna receiving the rf signal.

53. The receiver of claim 51, wherein the module includes a digital signal processor (DSP).

54. The receiver of claim 51, wherein the module is configured to reconstruct at least some distorted portions of the signal being processed, wherein the at least some distorted portions are identified by slope discontinuities.

55. The receiver of claim 51, wherein at least one distorted portion is reconstructed by replacing the distorted portion with an undistorted portion, the undistorted portion being an inverse in the signal of the distorted portion.

56. An rf receiver, comprising:

a signal input configured to receive an rf signal;

a converting component receiving the rf signal from the signal input and configured to output a non-continuous representation thereof; and

a processing component receiving the non-continuous representation from the converting component and extracting baseband information therefrom prior to any conversion of the non-continuous representation to a continuous representation, the processing component reconstructing the signal in the non-continuous domain prior to extracting baseband information.

57. The receiver of claim 56, wherein the converting component is established by an analog-to-digital converter (ADC).

58. The receiver of claim 56, wherein the processing component is established by a digital signal processor (DSP).

59. The receiver of claim 56, wherein the signal input receives rf from an antenna connected thereto.

60. The receiver of claim 56, wherein the processing component uses a fast Fourier transform (FFT) to reconstruct a distorted portion of the rf.

61. The receiver of claim 56, wherein the processing component uses wavelet analysis to reconstruct a distorted portion of the rf.

62. A radio, comprising:

a signal input;

an analog to digital converter (ADC) electrically connected to the signal input and outputting a digitized signal representative of an analog signal received at the signal input prior to rendering an IF signal or a demodulated signal;

a digital processor electrically connected to the ADC, the digital processor being configured to decode and extract information from the digitized signal;

a mixer generating an intermediate frequency (IF) signal based on the waveform; and

a demodulator decoding useful information from the IF signal, wherein at least the mixer and demodulator are embodied in the digital processor.

63. A receiver, comprising:

a filtering circuit receiving and filtering an electromagnetic signal;

an analog to digital converter (ADC) electrically connected to the filtering circuit and outputting a digitized signal representative of the electromagnetic signal; and

a digital processor electrically connected to the ADC, the digital processor reconstructing at least one corrupted portion of the signal prior to extracting useful information from the digitized signal representative of the electromagnetic signal while the digitized signals remains a digitized signal.

64. The receiver of claim 63, wherein the digital processor reconstructs the digitized signal.

65. The receiver of claim 63, wherein the ADC digitizes the signal prior to any analog demodulation thereof.

66. The receiver of claim 63, wherein the filtering circuit is controlled and tuned by the processor.

67. The receiver of claim 63, further comprising an amplifier connected to the filter.

68. The receiver of claim 67, wherein the filtering circuit is controlled and tuned by the processor.

69. The receiver of claim 63, wherein the processor reconstructs the digitized signal such that spurious signal elements and noise are removed therefrom.

70. The receiver of claim 63, wherein the processor reconstructs the digitized signal such that a desired signal is enhanced and amplified.

71. An rf receiver, comprising:

a signal input;

a filtering circuit electrically connected to the signal input;

an analog to digital converter (ADC) electrically connected to the filtering circuit for receiving an analog signal therefrom and outputting a digitized signal in response, the analog signal having corruptions;

a digital signal processor (DSP) electrically connected to the ADC, the DSP digitally generating a baseband signal representing baseband information carried by the analog signal, the baseband signal not being analog, the baseband signal being repaired relative to the analog signal in that portions of the baseband signal corresponding to the corruptions in the analog signal are not corrupted.

72. The receiver of claim 71, wherein the DSP generates a reconstructed waveform using the analog signal.

73. The receiver of claim 71, wherein the DSP outputs the reconstructed waveform in accordance with a predetermined reconstruction paradigm.

74. The receiver of claim 71, wherein the DSP includes reconstruction means for effecting method steps to implement a predetermined reconstruction paradigm, the method steps including:

(a) receiving both a positive half and a negative half of the digitized rf signal;

(b) analyzing the positive and negative halves to identify distorted portions and undistorted portions thereof; and

(c) removing at least some of the distorted portions and replacing each with a respective replacement portion to thereby produce the reconstructed waveform, each replacement portion being based on at least some of the undistorted portions.

75. The receiver of claim 71, wherein the filtering circuit includes a preamplifier filter circuit (PFC) electrically connected to an antenna and ADC for amplifying and filtering a signal from the antenna prior to sending the signal to the ADC, wherein the PFC includes:

a frequency bandpass filter for attenuating signals having a frequency not equal to a pass frequency, the pass frequency being dynamically established; and

an amplifier for increasing, by a gain factor, the amplitude of signals having the pass frequency.

76. The receiver of claim 75, further comprising a tuning control element for establishing a pass frequency, wherein

the DSP outputs a gain adjust signal when the rf signal input to the DSP is characterized by an amplitude outside of a predetermined amplitude range the gain factor based on the gain adjust signal;

and wherein

the pass frequency is established based on at least one of;

the pass frequency, and the gain adjust signal.

77. The receiver of claim 76, in combination with an rf transmitter.

78. A method for processing a modulated signal, comprising:

receiving the modulated signal;

converting the signal to a digital signal prior to extracting more than one IF signal therefrom, for subsequent processing of the digital signal to extract from the digital signal while in the digital domain baseband information carried by the modulated signal; and

reconstructing distorted signal portions while in the digital domain, the reconstructing not including only downconversion or demodulation.

79. The method of claim 78, wherein the reconstructing is effected prior to rendering the digital signal to the baseband domain.

80. An apparatus comprising:

a converter receiving as input an analog signal of a first frequency that has not been downconverted in the analog domain by the apparatus, the converter outputting a digitized signal representing the analog signal; and

a hardware module electrically connected to the converter, the module being configured with software to decode and extract baseband information from the digitized signal, wherein the module uses the digitized signal to generate a reconstructed waveform of a second frequency different from the first frequency.