Optical signal reception device for receiving DQPSK modulated signal

摘要

An optical signal reception device is disclosed that receives and demodulates an optical signal modulated by DQPSK and performs logical inversion and other controls to transit to the object reception state. The signal reception device includes a front end including a delay interferometer and an opto-electric conversion element that receive the DQPSK optical signal and convert it into an in-phase signal and an orthogonal signal, a clock regenerator that regenerates a clock signal based on the in-phase signal and the orthogonal signal, a multiplexer that multiplexes the in-phase signal and the orthogonal signal, a reception frame processing unit that detects frame synchronization based on the signal multiplexed by the multiplexer and de-maps the received frames, and a controller that, based on out-of-frame-synchronization information (LOF/OOF) from the reception frame processing unit, performs logical inversion control in the clock regenerator, multiplexing timing control in the multiplexer, and controls the delay interferometer in the front end so as to transit to the object reception state.