Upstream transmission using multiple transmission tags and downstream acknowledgements in conditional access packets
US5517502A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 1995 |
| Grant date | May 14, 1996 |
| Priority date | — |
| Expiry date | Mar 2, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/4623
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Upstream transmissions in a two-way communications network are effected from subscriber terminals in upstream packets having one of a plurality of different separately acknowledgeable acknowledgment tags. Downstream acknowledgments of upstream messages are contained in CA packets multiplexed with product packets to form a transport bitstream. The transport bitstream is applied to a digital conditional access module (DCAM) in the terminal which is controlled by the conditional access data bits of the CA packets. The DCAM includes a status register for storing the acknowledgment bits of the CA packets, which bits are coupled by a microprocessor for controlling the upstream transmitter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.