Apparatus and method for communicating an input signal in polar representation

• US 7,529,522 B2
• Filed: 10/18/2006
• Issued: 05/05/2009
• Est. Priority Date: 10/21/1998
• Status: Expired due to Fees

• Current Assignee: ParkerVision, Inc.
• Original Assignee: ParkerVision, Inc.
• Inventors: Moses, Charley D., Cook, Robert W., Rawlins, Gregory S., Bultman, Michael J., Sorrells, David F., Looke, Richard C., Rawlins, Michael W.
• Primary Examiner(s): NGUYEN, SIMON
• Application Number:
  US11/582,367
• Publication Number:
  US 20070105510A1
• Time in Patent Office: 930 Days
• Field of Search: 455/76, 455/91, 455102-105, 455108-1142, 455255-265, 375/295, 375298-308
• US Class Current: 455/91
• CPC Class Codes: H03C 1/62 Modulators in which amplitude of carrier component in output is dependent upon strength of modulating signal, e.g. no carrier output when no modulating signal is present H03C1/28 - H03C1/34, H03C1/46, H03C1/48 take precedence
• CPC Class Codes: H03C 3/38 by converting amplitude modulation to angle modulation
• CPC Class Codes: H03C 3/40 using two signal paths the outputs of which have a predetermined phase difference and at least one output being amplitude-modulated
• 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
• CPC Class Codes: H04B 1/04 Circuits
• CPC Class Codes: H04B 1/40 Circuits
• CPC Class Codes: H04B 2001/0491 with frequency synthesizers, frequency converters or modulators
• CPC Class Codes: H04B 7/12 Frequency diversity

Abstract

A method and system is described wherein a signal with a lower frequency is up-converted to a higher frequency. In one embodiment, the higher frequency signal is used as a stable frequency and phase reference. In another embodiment, the invention is used as a transmitter. The up-conversion is accomplished by controlling a switch with an oscillating signal, the frequency of the oscillating signal being selected as a sub-harmonic of the desired output frequency. When the invention is being used as a frequency or phase reference, the oscillating signal is not modulated, and controls a switch that is connected to a bias signal. When the invention is being used in the frequency modulation (FM) or phase modulation (PM) implementations, the oscillating signal is modulated by an information signal before it causes the switch to gate the bias signal. In the amplitude modulation implementation (AM), the oscillating signal is not modulated, but rather causes the switch to gate a reference signal that is substantially equal to or proportional to the information signal. In the FM and PM implementations, the signal that is output from the switch is modulated substantially the same as the modulated oscillating signal. In the AM implementation, the signal that is output from the switch has an amplitude that is a function of the information signal. In both embodiments, the output of the switch is filtered, and the desired harmonic is output.

Claims

1. An apparatus for communicating an input signal, comprising:

a circuit comprising a resistor coupled to a switch and configured to receive a first signal that represents an amplitude of the input signal, to receive a second signal that represents a phase of the input signal, and to gate the switch to produce a third signal that has a plurality of harmonics; and

a filter coupled to the circuit and configured to isolate at least one of the plurality of harmonics.

2. An apparatus for communicating an input signal, comprising:

a circuit configured to receive a first signal that represents an amplitude of the input signal, to receive a second signal that represents a phase of the input signal, and to produce a third signal that has a plurality of harmonics, wherein the circuit comprises a resistor coupled to a switch at a first terminal of the switch, the resistor is configured to receive the first signal, the switch is configured to receive the second signal at a control terminal of the switch, and the second signal is configured to cause the switch to gate the first signal to produce the third signal at the first terminal of the switch; and

a filter coupled to the circuit and configured to isolate at least one of the plurality of harmonics.

3. The apparatus of claim 2, wherein the switch is a semiconductor device.

4. The apparatus of claim 3, wherein the semiconductor device is a transistor.

5. The apparatus of claim 2, further comprising a capacitor coupled between the first terminal of the switch and a second terminal of the switch.

6. The apparatus of claim 2, wherein a second terminal of the switch is configured to receive a third voltage.

7. An apparatus for communicating an input signal, comprising:

a circuit configured to receive a first signal that represents an amplitude of the input signal, to receive a second signal that represents a phase of the input signal, and to produce a third signal that has a plurality of harmonics, wherein the circuit comprises a resistor coupled to a switch at a first terminal of the switch, the resistor is configured to receive the second signal, the switch is configured to receive the first signal at a control terminal of the switch, and the first signal is configured to cause the switch to gate the second signal to produce the third signal at the first terminal of the switch; and

a filter coupled to the circuit and configured to isolate at least one of the plurality of harmonics.

8. The apparatus of claim 7, wherein the switch is a semiconductor device.

9. The apparatus of claim 8, wherein the semiconductor device is a transistor.

10. The apparatus of claim 7, further comprising a capacitor coupled between the first terminal of the switch and a second terminal of the switch.

11. The apparatus of claim 7, wherein a second terminal of the switch is configured to receive a third voltage.

12. A method for communicating an input signal, comprising:

gating, with a switch, a first signal, that is conducted through a resistor, at a rate that is a function of a second signal to produce a third signal, wherein the first signal represents an amplitude of the input signal, the second signal represents a phase of the input signal, and the third signal has a plurality of harmonics; and

isolating at least one of the plurality of harmonics.

13. The method of claim 12, further comprising:

shaping a pulse of the third signal.

14. The method of claim 12, wherein the first signal is one of an information signal and a bias signal.

15. The method of claim 12, wherein the second signal is a rectangular wave.

16. The method of claim 12, wherein at least one of the first signal and the second signal is at least one of frequency modulated, phase modulated, and amplitude modulated.

17. A method for communicating an input signal, comprising:

gating, with a switch, a first signal, that is conducted through a resistor, at a rate that is a function of a second signal to produce a third signal, wherein the first signal represents a phase of the input signal, the second signal represents an amplitude of the input signal, and the third signal has a plurality of harmonics; and

isolating at least one of the plurality of harmonics.

18. The method of claim 17, further comprising:

shaping a pulse of the third signal.

19. The method of claim 17, wherein the first signal is one of an information signal and a bias signal.

20. The method of claim 17, wherein the second signal is a rectangular wave.

21. The method of claim 17, wherein at least one of the first signal and the second signal is at least one of frequency modulated, phase modulated, and amplitude modulated.