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:
Jan. 13, 1987
Filed:
Dec. 03, 1984
Steven A Steckler, Clark, NJ (US);
Alvin R Balaban, Lebanon, NJ (US);
RCA Corporation, Princeton, NJ (US);
Abstract
A phase locked loop system is described in the context of a digital television receiver. The system includes a band-pass filter which shifts the phase of burst samples provided to it by 33.degree.. This phase shift makes the zero-crossing points of the filtered burst signal coincident with the I color difference signal sampling phase relative to the unfiltered burst signal. The phase locked loop uses a zero-crossing phase detector to develop a control signal for a VCO. The oscillatory signal provided by the VCO has a frequency of, for example, four times the frequency of the burst, but shifted in phase relative to the burst to allow sampling composite video signal coincident with the phase of at least one of the I and Q color difference signals.