NEW MULTIPLEXED DIGITAL SUBSCRIBER TRANSMISSION-SYSTEM FOR SUPPORTING ISDN BASIC-I SERIES INTERFACES

Subscriber transmission systems are designed considering such transmission mediums as metallic cables, optical fibers, and radio. Multiplexed digital subscriber transmission technology is adopted to provide ISDN basic interfaces. NTT started providing these services in April, 1988. An enhanced mulitiplexed digital subscriber transmission system is developed. This configuration features (a) miniaturization using LSls, (b) a changing multiplexed method for connecting digital synchronous terminals, and (c) less limitation on equipment increase. Also, another multiplexed digital subscriber transmission system is developed to handle small demands. This last system is highly attractive in economically constructing ISDN nationwide.