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:
Feb. 04, 1992
Filed:
Oct. 19, 1990
Richard W Citta, Oak Park, IL (US);
Carl G Eilers, River Forest, IL (US);
Zenith Electronics Corporation, Glenview, IL (US);
Abstract
A co-channel interference reduction system for digital high definition television includes a transmitter having a modulo 4 processing precode filter. A receiver includes a pair of selectable video processing modes. The first mode provides a comb filter for removing co-channel interference signals together with a modulo 4 interpreter for restoring the four level data signal despite the intersymbol interference signal introduced by the comb filter segment. In the alternate mode operable in the absence of co-channel interfering signals, a level slicer and postcoder are used to restore the precoded signal to the original four level data signal.