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. 22, 1992
Filed:
Mar. 07, 1991
Kouei Misaizu, Kawasaki, JP;
Hiroshi Ohnishi, Tokyo, JP;
Matushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
An asynchronous quadrature demodulator which comprises an asynchronous quadrature detector, a frequency compensating circuit for estimating and compensating a frequency offset between an oscillating frequency of a local oscillator of the asynchronous quadrature detector and a frequency of a received carrier frequency on the basis of correcting signals, a base band complex equalizer for eliminating a transmission-channel distortion due to a multiplex transmission and a data demodulator. Thereby, a reference carrier recovery circuit becomes unnecessary. Thus, the structure of the demodulator can be simplified. Further, the demodulator can stably operate on the transmission channel.