OPTICAL LOOPBACK SYSTEM WITH SELF-POLAIZATION-STABILIZATION FUNCTION AND WAVELENGTH DIVISION MULTIPLEXING - PASSIVE OPTICAL NETWORK SYSTEM

摘要

PURPOSE: An optical loop-back system and wavelength division multiple passive optical network using the same are provided to stably maintain the polarization light of a signal in a receiver by reducing the change of polarized light by an optical cable. CONSTITUTION: A 45 degree polarization unit(122) is installed in a subscriber device(120). The 45 degree polarization unit offsets the polarization change of an upward signal. The 45 degree polarization unit is a Faraday rotator. A reflective optical modulator(121) is a reflective semiconductor optical amplifier, a laser diode, and a reflective electronic absorption modulator. The 45 degree polarization unit is installed in the front side of the reflective optical convertor.