OPTICAL SIGNAL PERFORMANCE MONITORING APPARATUS, PARTICULARLY FOR MONITORING DISTORTION OF AN OPTICAL SIGNAL GENERATED IN ITS TRANSMISSION AND RECEPTION BY USING A CHANGE IN DISTRIBUTION OF DATA ACCORDING TO A CHANGE OF A REFERENCE VOLTAGE

摘要

PURPOSE: An optical signal performance monitoring apparatus, particularly for monitoring distortion of an optical signal generated in its transmission and reception by using a change in distribution of data according to a change of a reference voltage, is provided to reduce an error rate of a bit error rate measuring method with a Q value, monitor performance of an optical signal irrespective of a data format. CONSTITUTION: An optical signal detector(120) converts an optical signal received through a transmission line into an electric signal. A reference voltage generator(160) generates reference voltages at certain intervals including an overall range of a signal level of the electric signal. A comparator(140) compares each signal level of electric signals with each size of reference voltages and calculates a difference value according to the comparison result. An average voltage calculator(180) calculates an average voltage value of the difference value by units of certain signal level. A memory(220) accumulatively stores the average voltage value. A processor(260) calculates a distribution function by using the accumulated average voltage values stored in the memory(220).