OPTICAL WAVELENGTH MULTIPLEX SIGNAL LEVEL FLUCTUATION DETECTOR IN OPTICAL PASSIVE TRANSMISSION SYSTEM

摘要

PROBLEM TO BE SOLVED: To surely detect and monitor interruption of an optical output of an electrooptic converter receiving an optical wavelength multiplex signal. SOLUTION: The optical wavelength multiplex signal level fluctuation detector is made up of an optical detection means 1 detecting a received optical wavelength multiplex signal in the optical passive transmission (optical wavelength multiplex transmission), a reference voltage setting means 2 dividing a voltage of its output to set a reference voltage, a comparison detection means 3 comparing a current voltage with the reference voltage and providing an output of a detection signal, and a state storage monitor means 4 storing the detected state momentarily. An output voltage from the optical detection means 1 and the reference voltage outputted from the reference voltage setting means 2 and stored are compared to surely detect interruption of an optical output of an electrooptic converter.