Method and system for down-converting an electromagnetic signal, and transforms for same, and aperture relationships

• US 7,865,177 B2
• Filed: 01/07/2009
• Issued: 01/04/2011
• Est. Priority Date: 10/21/1998
• Status: Expired due to Fees

• Current Assignee: ParkerVision, Inc.
• Original Assignee: ParkerVision, Inc.
• Inventors: Cook, Robert W., Rawlins, Gregory S., Bultman, Michael J., Sorrells, David F., Moses, Charley D., Looke, Richard C., Rawlins, Michael W.
• Primary Examiner(s): Bhattacharya; Sam
• Application Number:
  US12/349,802
• Publication Number:
  US 20090221257A1
• Time in Patent Office: 727 Days
• Field of Search: 455/413, 455/113, 455/118, 455/130, 455/131, 455/182.1, 455/190.1, 455/191.1, 455/313, 455/323, 455/343, 455/350, 327/113, 375/130, 375/142, 375/143, 375/150, 375/152, 375/316, 375/343
• US Class Current: 455/413
• CPC Class Codes: H03D 7/00 Transference of modulation from one carrier to another, e.g. frequency-changing H03D9/00, H03D11/00 take precedence; dielectric amplifiers, magnetic amplifiers, parametric amplifiers used as a frequency-changers H03F

Abstract

Methods, systems, and apparatuses, and combinations and sub-combinations thereof, for down-converting an electromagnetic (EM) signal are described herein. Briefly stated, in embodiments the invention operates by receiving an EM signal and recursively operating on approximate half cycles (½, 1½, 2½, etc.) of the carrier signal. The recursive operations can be performed at a sub-harmonic rate of the carrier signal. The invention accumulates the results of the recursive operations and uses the accumulated results to form a down-converted signal. In an embodiment, the EM signal is down-converted to an intermediate frequency (IF) signal. In another embodiment, the EM signal is down-converted to a baseband information signal. In another embodiment, the EM signal is a frequency modulated (FM) signal, which is down-converted to a non-FM signal, such as a phase modulated (PM) signal or an amplitude modulated (AM) signal.

Claims

1. A system for down-converting an electromagnetic signal, comprising:

a first matched filtering/correlating module that receives an input signal, wherein said first matched filtering/correlating module down-converts said input signal according to a first control signal and outputs a first down-converted signal;

a second matched filtering/correlating module that receives said input signal, wherein said second matched filtering/correlating module down-converts said input signal according to a second control signal and outputs a second down-converted signal; and

a first combiner module that combines said second down-converted signal and said first down-converted signal and outputs a first channel down-converted signal.

2. The system of claim 1, wherein said input signal is a RF carrier signal that is AM, FM, or PM modulated with an information signal.

3. The system of claim 2, wherein said first channel down-converted signal is a baseband signal.

4. The system of claim 2, wherein said first channel down-converted signal is an intermediate frequency signal.

5. The system of claim 1, further comprising:

a third matched filtering/correlating module that receives an input signal, wherein said third matched filtering/correlating module down-converts said input signal according to a third control signal and outputs a third down-converted signal;

a fourth matched filtering/correlating module that receives said input signal, wherein said fourth matched filtering/correlating module down-converts said input signal according to a fourth control signal and outputs a fourth down-converted signal; and

a second combiner module that combines said fourth down-converted signal and said third down-converted signal and outputs a second channel down-converted signal.

6. The system of claim 5, wherein said first combiner module and said second combiner module each comprise a differential amplifier.

7. The system of claim 5, further comprising:

a first filter that filters said first down-converted signal;

a second filter that filters said second down-converted signal;

a third filter that filters said third down-converted signal; and

a fourth filter that filters said fourth down-converted signal.

8. The system of claim 7, wherein said first, second, third, and fourth filters each comprise a low-pass filter.

9. The system of claim 8, wherein each said low-pass filter comprises a resistor and a capacitor.

10. The system of claim 5, further comprising a low-noise amplifier that amplifies said input signal.

11. The system of claim 5, wherein said input signal comprises an RF I/Q modulated signal.

12. The system of claim 11, wherein said first channel down-converted signal comprises an I-phase information signal portion of said RF I/Q modulated signal, and wherein said second channel down-converted signal comprises a Q-phase information signal portion of said RF I/Q modulate signal.

13. The system of claim 12, wherein a second control signal pulse of said second control signal occurs 1.5 cycles of a frequency of said input signal after the occurrence of a first control signal pulse of said first control signal;

wherein a fourth control signal pulse of said fourth control signal occurs 1.5 cycles of said frequency of said input signal after the occurrence of a third control signal pulse of said fourth control signal; and

wherein said third control signal pulse occurs 0.75 cycles of said frequency of said input signal after the occurrence of said first control signal pulse.

14. A method for down-converting an electromagnetic signal, comprising:

receiving an input signal at a first matched filtering/correlating module;

down converting said input signal at said first matched filtering/correlating module according to a first control signal and outputting a first down-converted signal;

receiving said input signal at a second matched filtering/correlating module;

down-converting said input signal at said second matched filtering/correlating module according to a second control signal and outputting a second down-converted signal; and

combining said second down-converted signal and said first down-converted signal to output a first channel down-converted signal.

15. An article of manufacture including a computer-readable medium having instructions stored thereon that, if executed by a computing device, cause said computing device to perform operations comprising:

receiving an input signal at a first matched filtering/correlating module;

down converting said input signal at said first matched filtering/correlating module according to a first control signal and outputting a first down-converted signal;

receiving said input signal at a second matched filtering/correlating module;

down-converting said input signal at said second matched filtering/correlating module according to a second control signal and outputting a second down-converted signal; and

combining said second down-converted signal and said first down-converted signal to output a first channel down-converted signal.