Television signal scrambling system and method
US4467353A · kind A · utility
13Cited by
12References
21Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 25, 1982 |
| Grant date | Aug 21, 1984 |
| Priority date | — |
| Expiry date | Mar 25, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/1713
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system for encoding or scrambling a television signal and for subsequently decoding or unscrambling the signal for presentation on the viewing screen of a television receiver. Encoding is achieved by suppressing the amplitude and changing the phase of the television signal carrier during selected horizontal blanking intervals. Decoding is achieved by synchronously detecting the horizontal blanking intervals of a received signal having a suppressed amplitude and changed carrier phase and restoring the original relative characteristics of the television signal during the detected intervals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.