| 摘要 |
A double-star communications system comprises a digital terminal, active pedestals coupled to the digital terminal via optical fibers, and subscribers' premises coupled to each active pedestal via existing telephone lines and via additional communications paths, which may comprise optical fibers or coaxial calbes. The digital terminal multiplexes broadband signal components, such as video channels, selected in response to subscriber control signals, with a multiplexed telephony signal and transmits these optically to an active pedestal, and receives the control signals, a multiplexed telephony signal, and optional upstream broadband signal components from the active pedestal. The active pedestal transmits and receives the signals on the first communications path, and demultiplexes the received multiplexed telephony signal and the broadband signal components. The received and tranmitted telephony signals are coupled to and from the telephone lines for providing telephone communications, and the selected broadband signal components are coupled to the additional communications paths. The active pedestal forwards to the digital terminal the control signals received from the subscriber via the additional communications paths, optionally multiplexed with an upstream broadband signal component.
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