Station Matrix System or Main Video Router System

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Station matrix or router enhances the professionalism in baseband operational activities. The matrix system is like the digital exchange that performs signal routing. The signal routing may include analog video signal, digital video signal, analog audio signal, digital audio signal etc. Station matrix system deals with route creation in commercial broadcast operation. The route is established between the router destination and source. The main facility is to make certain sources to be available for various destinations what are connected to the station matrix. This feature decreases the number of distribution modules needed for the whole station.


The routing system is named as matrix because it performs its operational activity in such a way that follows the mechanism of cross point matrix. The matrix system has some input ports and output ports. The input ports are regarded as source of the matrix and the output port is regarded as the destination port. Video is made destined via the router’s output ports. The operational algorithm has been implemented in the matrix system. One can configure permanent or momentary route by commissioning the router’s logical module. The key thing to be reminding that a single source can be routed to multiple destinations but a single destination cannot be destined for multiple sources. 
Figure: Video routing by cross point technique (s=source, d=destination)


Most of the broadcast production vendor make video router. Evertz and Grass Valley are two renowned production vendor in broadcast world.  Evertz has introduced 64x64 matrix system which supports SD video (embedded or de-embedded).  This video router has 64 inputs and 64 outputs. All of the I/O ports support video signal of SD format. The block diagram of this router is as follows. 
 Figure: Block diagram of Evertz Xenon SD Video Router (XE4-64×64)

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