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:
Aug. 28, 1979
Filed:
May. 25, 1978
Yukinobu Ishigaki, Yamato, JP;
Teruo Muraoka, Yokohama, JP;
Victor Company of Japan, Ltd., Yokohama, JP;
Abstract
A system comprising a demodulator for demodulating an input FM signal which has been subjected to interference by another FM signal, an envelope detector for detecting the envelope of fluctuation of the amplitude of the input signal, an AGC circuit for controlling the level of the input signal supplied to the envelope detector, a capacitor for passing only the AC component of the output of the envelope detector, a circuit having a transfer characteristic of a hyperbolic function and converting the waveform of the AC component, an analog multiplier supplied at its x input terminal with the output of the waveform converting circuit and producing a distortion cancellation signal, a first operation circuit supplied with the output signal of the demodulator and with the distortion cancellation signal and carrying out an operation such as substantially cancelling the interference distortion of the demodulated signal with the distortion cancellation signal, a delay circuit for delaying the output signal of the first operation circuit or of the demodulator by a specific time, and a second operation circuit supplied with the output signal of the first operation circuit or of the demodulator and with the output signal of the delay circuit, thereby carrying out a signal combining operation and supplying the resulting output signal to the y input terminal of the analog mutliplier. The output of the first operation circuit is demodulated signal in which the interference distortion has been canceled and thus removed.