Patent · US Expired

Pay television

US5272751A · kind A · utility

4Cited by
10References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 12, 1993
Grant dateDec 21, 1993
Priority date
Expiry dateMar 12, 2013

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N7/1713
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

In a pay television device, a horizontal sync signal, a vertical sync signal, and the like are removed from a composite video signal, and first-frequency and second-frequency signals for descrambling processing are attached in the intervals corresponding to the removed signals, thus eliminating the need for multiplexing signals which are necessary for descrambling processing on an audio signal.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.