Method for cascading detachable conditional access modules, circuit for inserting a predetermined sequence and circuit for detecting the said sequence in order to implement the method
US6396850B1 · kind B1 · utility
15Cited by
13References
6Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 24, 1996 |
| Grant date | May 28, 2002 |
| Priority date | — |
| Expiry date | Sep 24, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/43853
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention concerns a method for cascading detachable conditional access modules as well as a circuit for inserting a predetermined sequence and a circuit for detecting the sequence. Each module receives a data stream formed of packets of fixed length separated by an interpacket space of fixed length. The interpacket spaces contain a constant predetermined sequence which does not interfere with the packets. The predetermined sequence may be used to regenerate a packet clock signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.