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. 22, 1989
Filed:
Oct. 28, 1988
Applicant:
Inventor:
Shoichi Mizoguchi, Tokyo, JP;
Assignee:
NEC Corporation, , JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03D / ;
U.S. Cl.
CPC ...
329 50 ; 329109 ; 329135 ;
Abstract
In a demodulator for demodulating a multilevel quadrature amplitude modulated signal specified by a plurality of output signal points arranged on an approximately octangular specific region into an in-phase baseband signal and a quadrature baseband signal and for converting the in-phase and the quadrature baseband signals into a demodulator output signal and an error signal, a validity decision circuit (40) is supplied with the in-phase and the quadrature baseband signals to decide that the error signal is valid when at least one reception signal point is outwardly of the approximately octangular specific region.