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:
Dec. 30, 1997
Filed:
Dec. 12, 1995
Gregory A Shreve, San Pedro, CA (US);
Kim S Guzzino, Los Angeles, CA (US);
Robert W Hulvey, Hermosa Beach, CA (US);
TRW Inc., Redondo Beach, CA (US);
Abstract
A digital phase error detector for locking to a color subcarrier signal in an analog video signal. The digital phase error detector includes a digitizer responsive to a sample clock which generates a first digital data stream from the analog video signal. Filtering circuitry filters the first digital data stream to generate a second data stream by substantially eliminating DC offset of the color subcarrier signal digitized by the digitizer. A mixer mixes the second digital data stream to generate a third digital data stream representing sum and difference frequencies of a product of the color subcarrier signal and a reference clock. An accumulator accumulates this product which represents a phase error between the color subcarrier signal and the reference clock. A voltage controlled oscillator is responsive to this phase error for generating the sample clock.