Fiber-optic distribution system for broadband signals

Abstract

A fiber-optic distribution system is disclosed which distributes broadband signals received by a network termination circuit from a broadband communications network (B-ISDN or cable-television network) among a plurality of subscriber terminals. The network termination circuit (4) contains devices for separating a forward channel and a backward channel. It also includes electric-to-optical and optical-to-electric transducers (5,6). The distribution system contains a fiber-optic multi-port coupler (10) which is made by the fusion technique and interconnects a plurality of optical fibers (12, 13, 14). On the subscriber's side, each of these optical fibers forms the forward channel and the backward channel for one of the terminals (32). On the network side, one of these optical fibers (16) forms the forward channel for the broadband signals, and all other optical fibers (17, 18) are combined to form the narrow-band backward channel. They are connected to a common large-area photodiode (6). As the backward channel is a narrow-band channel, the fact that large-area photodiodes, such as PIN diodes, are relatively slow does not cause any bandwidth problems.

Dependencies are inferred from the claim text.