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

• US 20020058490A1
• Filed: 04/20/2001
• Published: 05/16/2002
• Est. Priority Date: 10/21/1998
• Status: Active Grant

• 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.
• Granted Patent: US 6,813,485 B2
• Time in Patent Office: Days
• US Class Current: 455/313
• 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: 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 7/12 Frequency diversity

Abstract

Methods, systems, and apparatuses, and combinations and sub-combinations thereof, for down-converting and up-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, {fraction (2/2)}, 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. 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.

Claims

1. An apparatus for down-converting electromagnetic signals, comprising:

a signal input device for receiving a modulated carrier signal;

an RC processor, coupled to said input device, having an RF switch and a capacitor; and

a waveform generator, coupled to said RF switch of said RC processor.

2. The apparatus of claim 1, wherein said signal input device is a cable.

3. The apparatus of claim 1, wherein said signal input device is an antenna.