| 摘要 |
A data switching system having a number of subscriber sets connected over a broad band transmission line capable of handling traffic within and without the voice frequency range to a switching center is described. The system handles transmissions of audio and video telephone conversations, television programs and data communications between connected parties. Subscriber sets are provided which have, in addition to the usual telephone circuit and character generator, a video receiver and transmitter, data terminals used as control elements and a common control device. The latter is connected over a subscriber line to the switching center for enabling the operation of the control elements as needed for the selected operating mode. In the switching center the subscriber line is connected parallel with more than one input of a multisectional switching network. One of the aforementioned inputs receives telephone traffic, another receives radio and television programs and others are used for video telephone and other data traffic in one or two directions. The various coupling elements in the switching network are operable independently of one another. |
