3894177 is referenced by 104 patents and cites 12 patents.

A system for distributing and routing a large number of audio-video signal channels is described. The system includes an input multiplexer and signal distribution networks, a matrix of switch groups and an output demultiplexer. In the input multiplexer the audio signals accompanying each video signal in each channel are digitized and the resulting digital signal angularly modulated to produce signals modulated by the digital signals and translated to a frequency region above the region of the video. A composite signal including the video and the angularly modulated audio signals are applied to the input distribution networks to drive a matrix of switch groups. Each output of the matrix switch has as many selectable inputs as there are input channels. Outputs are organized in groups to facilitate input distribution. Inputs are organized in blocks to facilitate input selection. An output demultiplexer is provided for each output and reconstructs the video and audio signals which are routed thereto by the matrix switch.

Signal distribution system
Application Number
Publication Number
Application Date
March 23, 1973
Publication Date
July 8, 1975
Woods Eric R
Thompson Russell G
Howell Norman E
LuKacher Martin
General Dynamics
H04N 07/00
H04N 05/268
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