Craig S Greenberg

US Patent:

52836509, Feb 1, 1994

Filed:

Sep 4, 1992

Appl. No.:

7/941356

Inventors:

David Koo - Briarcliff Manor NY
Craig B. Greenberg - Mohegan Lake NY
Takashi Sato - Tokyo, JP

Assignee:

North American Philips Corporation - New York NY

International Classification:

H04N 708
H04N 514
H04N 5208
H04N 5213

US Classification:

348614

Abstract:

A system for improved ghost cancellation for use in particular in television receivers. The system featuring a superior ghost cancellation reference (GCR) signal which exhibits improved performance in noisy environments and which exhibits the flat and wide bandwidth necessary for effective channel characterization which also exhibiting a higher and more evenly distributed amplitude versus time characteristic than that provided by known, non-cyclic ghost cancellation signals. The GCR signal is encoded a selected television line of an eight field sequence of lines however the polarity of the GCR signal is reversed selectively from field to field prior to inserting it in respective television lines. At a decoder or television receiver incorporating the invention, the selected television lines are combined in a manner which provides for both a robust received GCR value and cancellation of the effects of pair-wise constant television line signals on the GCR signals.