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. 11, 1987
Filed:
May. 29, 1986
Edward R Campbell, III, Tabernacle Township, Burlington County, NJ (US);
Henry G Lewis, Jr, Hamilton Square, NJ (US);
RCA Corporation, Princeton, NJ (US);
Abstract
An automatic deghosting system synchronously demodulates IF television signals to generate baseband composite video signals. A strong RF ghost signal having a carrier phase that differs from that of the desired signal may cause demodulation phase errors, causing quadrature distortion in the baseband video signals. The circuitry shown in this disclosure synchronously demodulates the quadrature component of the IF television signals and develops a signal proportional to the difference between the values of the baseband quadrature signal immediately before and immediately after the leading edge of the vertical sync pulse. This signal, which is proportional to the demodulation phase error, is used to control a phase locked loop that regenerates the in-phase and quadrature carrier signals used by the synchronous demodulators to substantially eliminate any demodulation phase error.