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:
Oct. 23, 1984
Filed:
Dec. 03, 1981
Applicant:
Inventor:
Akiyuki Yoshisato, Soma, JP;
Assignee:
Alps Electric Co., Ltd., Tokyo, JP;
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03D / ; H03L / ;
U.S. Cl.
CPC ...
329122 ; 329 50 ; 331 17 ; 331 23 ; 455266 ;
Abstract
In an FM demodulation circuit which demodulates an FM signal by the use of a phase-lock loop constructed of a phase comparator, a loop filter and a voltage-controlled oscillator, the loop filter is a variable loop filter whose loop band width is varied in correspondence with the modulation band width and the carrier/noise ratio of the input signal by a base band processing circuit.