Cable network data transmission system
US4623920A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 20, 1983 |
| Grant date | Nov 18, 1986 |
| Priority date | — |
| Expiry date | Jan 20, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/1675
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system for providing television, information and data signals via a transmission network to selected subscribers, to groups of subscribers, or to all subscribers connected in common to the transmission network. An address code signal is stored at the subscriber station, and an option code signal is sent to the particular subscriber station from a head end of the network. Signals having an address portion designative of the option code or address code signal are sent down the transmission line and are translated by the subscriber station in the event the address matches the first and second code signal. Thus signals can be sent to all subscribers which have option codes designated by the address of data packets transmitted down the transmission line. These groups of subscribers can be all subscribers, individual smaller groups of subscribers, or a group consisting of even a single subscriber. The option codes can be changed from the head end at will. Consequently data can be transmitted to various subscribers designated form the head end under its complete control. The data can be control signals for controlling the unscrambling of pay-TV signals, software for operating a microcom…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.