What is time multiplexed space switching? Explain with a neat diagram.

Time division switches, an inlet or an outlet corresponded to a particular subscriber line with one speech sample appearing each 125 µs on the line. These switches are used in local exchanges. We here consider switches which are needed in transit exchanges. Now, the inlets and outlets are trunks that carry time division multiplexed data streams. We call such switches time multiplexed switches. A time multiplexed time division space switch is demonstrated in figure. There are N incoming trunks and N outgoing trunks, all carrying a time division multiplexed stream of M samples per frame. All frames are of 125-µs time duration. In individual frame time, a total of MN speech samples have to be switched. Individual sample duration, 125/M microseconds, is typically referred to as a time slot. N-samples are switched, in one time slot. Figure demonstrates an output-controlled switch. The output of this is cyclically scanned. There is a 1-to-M relationship among the outlets and the control memory locations that is there are M locations in the control memory consequent to each outlet.

FIG - Time Multiplexing Space Switch