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:
May. 09, 1989
Filed:
Mar. 03, 1988
Neal D Becker, Thurmont, MD (US);
Ajit Shenoy, Silver Spring, MD (US);
Lin-nan Lee, Potomac, MD (US);
Communications Satellite Corporation, Washington, DC (US);
Abstract
An analog TV system includes a transmitter which produces a horizontal unique pulse sequence during each horizontal blanking interval. The pulse sequence is amplitude modulated between two levels to define a horizontal unique word for horizontal synchronization. The frequency of the pulse sequence is selected for use by the receiver section as the color subcarrier phase reference. The average level of the pulse sequence is set at the transmitter and used at the receiver for DC restoration in a clamping circuit. The peak amplitude of the pulses of the pulse sequence define a reference level against which a receiver producing local reference is compared for AGC. As four separate functions are accomplished by a single unique pulse sequence transmitted during the horizontal blanking interval, which four functions are typically accomplished using four separate signals transmitted sequentially during the horizontal blanking interval, a substantial portion of the horizontal blanking interval remains available for other data.