| 摘要 |
In a service integrated multiplex signal transmission system for transmitting narrowband and broadband signals between a central exchange terminal and a subscriber terminal, which system includes a light conductor path connected between the terminals, a transmitter device at one terminal composed of sources of such narrowband and broadband signals and multiplexers connected for combining the signals provided by the sources into a multiplex signal and for supplying such multiplex signal to the light conductor path, and a receiver device at the other terminal composed of demultiplexers connected to the light conducting path for receiving multiplex signals from that path and separating the received multiplex signals into narrowband signals and broadband signals, the device at the subscriber terminal being normally supplied with operating power by local utility mains, and including a charge accumulator for supplying operating power independently of the local mains, connected for supplying such power to the device at the subscriber terminal in the event of interruption of the power supply provided by the local mains, and the system being arranged to effect signal transmission at a reduced bit rate in the event of such local mains power interruption, the light conductor path is constructed to present separate optical transmission channels for the narrowband signals and for the broadband signals.
|
