System for ghost cancellation comprising an improved GCR signal sequence
US5283650A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 1992 |
| Grant date | Feb 1, 1994 |
| Priority date | — |
| Expiry date | Sep 4, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/211
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.