Process for the broadcasting of conditional access programs permitting a progressive access to such programs
US5442701A · kind A · utility
31Cited by
1References
9Claims
0Family size
Assignees
Inventors
Key dates
| Filing date | Dec 27, 1993 |
| Grant date | Aug 15, 1995 |
| Priority date | — |
| Expiry date | Dec 27, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/8549
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A process for broadcasting conditional access programs which permits a progressive access. Scrambled program data is transmitted along with partial access checking messages and complete access checking messages such that subscribers having a partial access right may descramble portions of the scrambled data corresponding to information regarding only the identity of the conditional access programs, and subscribers having a complete access right may descramble the remainder of the scrambled data and view the conditional access programs. The conditional access programs may be television pictures, radio programs, or data broadcasts.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.