Point-to-multipoint optical communication system

Abstract

Provided is a point-to-multipoint optical communication system capable of extending a transmission distance between a subscriber apparatus and a station apparatus without changing wavelengths of an upstream optical signal and a downstream optical signal, which are used in both of the apparatuses. The point-to-multipoint optical communication system includes, as a basic configuration thereof, an optical network for connecting one station apparatus () to a plurality of (n) subscriber apparatuses (). Among m basic configurations, one station-side wavelength multiplexer/demultiplexer (), one optical fiber transmission line (), and one subscriber-side wavelength multiplexer/demultiplexer () are shared. The point-to-multipoint optical communication system further includes a station-side repeating unit () and a subscriber-side repeating unit () each including the one wavelength multiplexer/demultiplexer (or) and m wavelength converters (or). An optical signal having a conventionally-used wavelength is used between the station apparatus () and the station-side repeating unit () and between the subscriber apparatus () and the subscriber-side repeating unit (), and an extensible optical signal, on which wavelength division multiplexing has been performed, is used between the wavelength multiplexers/demultiplexers (and) via the optical fiber transmission line ().