The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 28, 1993
Filed:
Feb. 01, 1991
Richard Posner, Woodland Hills, CA (US);
Zvi Regev, West Hills, CA (US);
MST, Inc., Westlake Village, CA (US);
Abstract
A narrow band complex input signal, typically having multiple independently modulated carriers, is processed to produce an output signal which, while containing the information in the input signal, is not an amplitude dependent signal, and thus can be transmitted through nonlinear media, such as a saturated power amplifier, as a less expensive and more power-efficient alternative over a conventionally required linear power amplifier. The process separates the multiple input signals into an amplitude-limited angle-modulated carrier component and an envelope component, and then combines these components by a form of pulse-duty-factor modulation such as pulse-duration modulation, at a sufficiently high sampling rate. The combined signal is input to a nonlinear power amplifier. Unwanted sidebands are rejected by bandpass filtering at the amplifier output so as to pass only the carrier and its signal bandwidth. The process can include an optical link interposed in the limited carrier path, utilizing suitable modulation and demodulation at the link input/output. A multiple amplifier embodiment utilizes a bank of parallel nonlinear amplifiers, each of which is driven by a pulse modulator. The amplitude-limited angle-modulated carrier is distributed to the modulators where envelope information is imposed in the form of interleaved sequential pulse-duty-factor modulation. The combined outputs of the nonlinear amplifiers provide the ultimate peak envelope power for transmission.