04947244 is referenced by 220 patents and cites 15 patents.

A video distribution system transmits selected video programs to a number of independently controlled video monitors. The video monitors are arranged in groups, each group being coupled to a distinct transmission medium. A program selector associated with each video monitor generates video connection requests which specify a video source to be connected to that video monitor. A two stage video switch apparatus couples specified video sources to specified video monitors. The first stage routes specified video signals from the video sources to the second stage, which is a frequency multiplexer. The frequency multiplexer then transmits the specified video signals for each group of video monitors in distinct frequency bands on one of the transmission mediums. Each video monitor within each group of monitors has a tuner that is tuned to receive the video signal in a distinct one of the frequency bands. In effect, the transmission medium for each group of video monitors has a separate transmission channel for each of the monitors in the group. Finally, the system has a controller which receives the video connection requests, and controls the video switch apparatus so that it couples specified video sources to specified video monitors.

Title
Video selection and distribution system
Application Number
7/346778
Publication Number
4947244
Application Date
May 3, 1989
Publication Date
August 7, 1990
Inventor
Jeffrey R Gile
San Mateo
CA, US
John W McMains
Saratoga
CA, US
Robert Snyder
Saratoga
CA, US
Larry L Peden
Monte Sereno
CA, US
Robert B Fenwick
Los Altos Hills
CA, US
Agent
Flehr Hohbach Test Albritton & Herbert
Assignee
On Command Video Corporation
CA, US
IPC
H04N 7/167
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