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. 13, 1987
Filed:
Sep. 24, 1985
Applicant:
Inventor:
Brian H Beech, Hampshire, GB;
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04N / ;
U.S. Cl.
CPC ...
358 23 ;
Abstract
A phase lock loop demodulator has its loop transfer function (F(s)) optimized to: F(s)=A+B/s+CF.sub.1 (s)+DF.sub.2 (s) where CF.sub.1 (s) is a chrominance sub-carrier term DF.sub.2 (s) is a sound sub-carrier term and A, B, C and D are constants whereby to minimize the phase error signal appearing at the output of the phase comparator (10) of the loop. An equalizer circuit (14) may be added at the output of the loop in which case the transfer function (F.sub.T (s)) of the equalizer circuit is as follows: F.sub.T (s)=KoKd+s/F(s) where F(s) is the transfer function of the loop amplifier circuit (12) and A, Ko and Kd are constants.