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

• US 7,065,162 B1
• Filed: 04/14/2000
• Issued: 06/20/2006
• Est. Priority Date: 04/16/1999
• Status: Expired due to Term

• Current Assignee: ParkerVision, Inc.
• Original Assignee: ParkerVision, Inc.
• Inventors: Cook, Robert W., Rawlins, Gregory S., Bultman, Michael J., Sorrells, David F., Moses, Charley D. Jr., Looke, Richard C., Rawlins, Michael W.
• Primary Examiner(s): Chin, Stephen
• Assistant Examiner(s): ODOM, CURTIS B
• Application Number:
  US09/550,642
• Time in Patent Office: 2,258 Days
• Field of Search: 375/344, 375/350, 455/327, 455/323, 455/333, 455/118, 455/313, 327/105, 327/159
• US Class Current: 375/343
• 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. An apparatus for down-converting an electromagnetic signal, comprising:

a capacitor having a first and second port;

a transistor having a source, gate and drain; and

a resonant structure having a first and second port,

wherein the first port of the capacitor is electrically coupled to the source or drain of the transistor, and the first port of the resonant structure is electrically coupled to the other of the source or drain of the transistor, and

wherein a control signal is electrically coupled to the gate of the transistor, and an RF source signal is electrically coupled to the first port of the resonant structure, and

wherein a value of capacitance for the capacitor is selected based on a frequency of energy transfer pulses, an aperture duration of the transistor, and a resistor value.

2. The apparatus of claim 1, wherein the value of capacitance for the capacitor is selected so that the capacitor discharges stored energy to a load when the transistor is open.

3. The apparatus of claim 1, wherein the value of capacitance (C_s) for the capacitor is selected such that

$C_s$

( R ) = ( 1 freqLO - Aperture_width - ln ⁡

( 0.841 ) ·

R )

wherein (freqLO) is the frequency of energy transfer pulses, (Aperture Width) is the aperture duration of the transistor, and (R) is the resistor value.

4. The apparatus of claim 1, wherein a duration of an aperture of pulses of the control signal is nominally equal to one-half of a period of the RF source signal.

5. The apparatus of claim 1, wherein the first port of the capacitor is electrically coupled to an impedance matching network.

6. The apparatus of claim 1, wherein the first port of the capacitor is electrically coupled to an amplifier.

7. The apparatus of claim 1, wherein the first port of the resonant structure is electrically coupled to an impedance matching network.

8. The apparatus of claim 1, wherein the transistor is a FET.

9. The apparatus of claim 1, wherein the transistor is a JFET.

10. The apparatus of claim 1, wherein the transistor is a MOSFET.

11. The apparatus of claim 1, wherein the capacitor discharges stored energy to a load at a controlled discharge rate.

12. An apparatus for down-converting an electromagnetic signal, comprising:

a first and second capacitor each having a first and second port;

a transistor having a source, gate and drain; and

a resonant structure having a first and second port,

wherein the first port of the first capacitor and the second port of the second capacitor are electrically coupled to one of the source or drain of the transistor, and the first port of the second capacitor and the first port of the resonant structure are electrically coupled to the other of the source or drain of the transistor,

wherein a control signal is electrically coupled to the gate of the transistor, and an RF source signal is electrically coupled to the first port of the resonant structure, and

wherein a value of capacitance for the first capacitor is selected based on a frequency of energy transfer pulses, an aperture duration of the transistor, and a resistor value.

13. The apparatus of claim 12, wherein the value of capacitance for the first capacitor is selected so that the capacitor discharges stored energy to a load when the transistor is open.

14. The apparatus of claim 12, wherein the value of capacitance (C_s) for the first capacitor is selected such that

$C_s$

( R ) = ( 1 freqLO - Aperture_width - ln ⁡

( 0.841 ) ·

R )

wherein (freqLO) is the frequency of energy transfer pulses, (Aperture Width) is the aperture duration of the transistor, and (R) is the resistor value.

15. The apparatus of claim 12, wherein a duration of an aperture of pulses of the control signal is nominally equal to one-half of a period of the RF source signal.

16. The apparatus of claim 12, wherein the first port of the first capacitor is electrically coupled to an impedance matching network.

17. The apparatus of claim 12, wherein the first port of the first capacitor is electrically coupled to an amplifier.

18. The apparatus of claim 12, wherein the first port of the resonant structure is electrically coupled to an impedance matching network.

19. The apparatus of claim 12, wherein the transistor is a FET.

20. The apparatus of claim 12, wherein the transistor is a JFET.

21. The apparatus of claim 12, wherein the transistor is a MOSFET.

22. The apparatus of claim 12, wherein the first capacitor discharges stored energy to a load at a controlled discharge rate.

23. An apparatus for down-converting an electromagnetic signal, comprising:

a capacitor having a first and second port; and

a first and second transistor each having a gate, drain and source,

wherein the first port of the capacitor is electrically coupled to one of the drain or source of the first transistor and the second port of the capacitor is electrically coupled to one of the drain or source of the second transistor, and the gate of the first transistor is electrically coupled to the gate of the second transistor,

wherein a control signal is electrically coupled to the gate of the first transistor and the gate of the second transistor, and an RF source signal is electrically coupled to the other of the drain or source of the first transistor and the other of the drain or source of the second transistor, and

wherein a value of capacitance for the capacitor is selected based on a frequency of energy transfer pulses, an aperture duration of the transistor, and a resistor value.

24. The apparatus of claim 23, further comprising:

a resonant structure having a first and second port,

wherein the first port of the resonant structure is electrically coupled to the other of the drain or source of the first transistor, and the second port of the resonant structure is coupled to the other of the drain or source of the second transistor.

25. The apparatus of claim 24, further comprising:

a first and second impedance each having a first and second port,

wherein the first port of the first impedance is electrically coupled to the first port of the resonant structure and the first port of the second impedance is electrically coupled to the second port of the resonant structure, and

wherein the RF source signal is electrically coupled to the second port of the first impedance and the second port of the second impedance.

26. The apparatus of claim 23, wherein the value of capacitance for the capacitor is selected so that the capacitor discharges stored energy to a load when one of the first and second transistors is open.

27. The apparatus of claim 23, wherein the value of capacitance (C_s) for the capacitor is selected such that

$C_s$

( R ) = ( 1 freqLO - Aperture_width - ln ⁡

( 0.841 ) ·

R )

wherein (freqLO) is the frequency of energy transfer pulses, (Aperture Width) is the aperture duration of the transistor, and (R) is the resistor value.

28. The apparatus of claim 23, wherein a duration of an aperture of pulses of the control signal is nominally equal to one-half of a period of the RF source signal.

29. The apparatus of claim 23, wherein the first port of the capacitor is electrically coupled to an amplifier.

30. The apparatus of claim 23, wherein the first and second ports of the capacitor are electrically coupled to first and second ports of a differential amplifier.

31. The apparatus of claim 23, wherein the first and second transistors are FETs.

32. The apparatus of claim 23, wherein the first and second transistors are JFETs.

33. The apparatus of claim 23, wherein the first and second transistors are MOSFETs.

34. The apparatus of claim 23, wherein the capacitor discharges stored energy to a load at a controlled discharge rate.

35. An apparatus for down-converting an electromagnetic signal, comprising:

a first and second capacitor each having a first and second port;

a transistor having a gate, drain and source; and

a load,

wherein the first port of the first capacitor and the first port of the second capacitor are electrically coupled to one of the drain or source of the transistor, the load and the second port of the second capacitor are electrically coupled to the other of the drain or source of the transistor,

wherein a control signal is electrically coupled to the gate of the transistor, and an RF source signal is electrically coupled to one of the drain or source of the transistor, and

wherein a value of capacitance for the first capacitor is selected based on a frequency of energy transfer pulses, an aperture duration of the transistor, and a resistor value.

36. The apparatus of claim 35, wherein the value of capacitance for the first capacitor is selected so that the capacitor discharges stored energy to a load when the transistor is open.

37. The apparatus of claim 35, wherein the value of capacitance (C_s) for the first capacitor is selected such that

$C_s$

( R ) = ( 1 freqLO - Aperture_width - ln ⁡

( 0.841 ) ·

R )

wherein (freqLO) is the frequency of energy transfer pulses, (Aperture Width) is the aperture duration of the transistor, and (R) is the resistor value.

38. The apparatus of claim 35, wherein a duration of an aperture of the transistor is nominally equal to one-half of a period of the RF source signal.

39. The apparatus of claim 35, wherein the first port of the first capacitor is electrically coupled to an impedance matching network.

40. The apparatus of claim 35, wherein the first port of the first capacitor is electrically coupled to an amplifier.

41. The apparatus of claim 35, wherein the first port of the second capacitor is electrically coupled to an impedance matching network.

42. The apparatus of claim 35, wherein the transistor is a FET.

43. The apparatus of claim 35, wherein the transistor is a JFET.

44. The apparatus of claim 35, wherein the transistor is a MOSFET.

45. The apparatus of claim 35, wherein the first capacitor discharges stored energy to a load at a controlled discharge rate.