Space-Division Digital Networks for Video Signals

Space-division digital-switching networks are proposed as switching systems of a future communication network suitable for introduction of new services. Network construction methods for video signals are considered. Hybrid-switching networks using two kinds of coding systems will be available for both simplification of equipment and high-quality transmission. Consideration is also given to future network formats, which will be gradually digitalized. Introduction of a pulse-stuffing synchronization system into switching networks is proposed here. For video signals, this system is presumed to be more economical than the mutual synchronization system. New techniques, such as junctor-stuffing synchronization and destuffing with qnantized clock rates, are discussed.