Individualized Still-Picture Communication on a Two-Way Broad-Band CATV System

The principle and the equipment developed for the field trial on individualized still-picture communication applicable to a two-way CATV system are explained. Individualized still-picture communication is realized by a oneframe time-division-multiplex technique which enables many subscribers to share a television transmission channel. This technique will largely increase the capability of conventional CATV systems. Two kinds of new services, i.e., still-picture information retrieval and still-picture two-way communication between subscribers, have been successfully tested with a model system located at the Suzuka Telecommunication Training School, Nippon Telegraph and TelePhone Public Corporation. Brief explanation is also given about still-picture information retrieval system using a polling method which is currently under development.