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:
Dec. 17, 1991
Filed:
Jan. 30, 1990
Mamoru Endo, Tokyo, JP;
Masahiro Hamatsu, Tokyo, JP;
Clarion Co., Ltd., Tokyo, JP;
Abstract
A signal processing circuit utilizes a convolver correlating a reference carrier signal with a received signal. The correlator output is detected and then demodulated to output the signal information originally present on the carrier. For a conventional AM signal the reference carrier signal is applied at a frequency offset from the AM center frequency. When the carrier is an FM signal, the reference signal is applied at a frequency equal to the center frequency of the FM signal. Similar procedures are followed for a spread-modulated AM signal, and the reference signal is modulated with a suitably timed-reverse replica of the pseudo-noise code. A similar procedure is used to process spread-spectrum frequency shift keyed FM signals.