Digital coherent receiving apparatus

摘要

A digital coherent receiving apparatus (100) includes a first oscillator (112) for outputting a local light signal of a fixed frequency, a hybrid unit (121, 122) mixing the local light signal with a light signal received by a receiver (111), a second oscillator (140) for outputting a sampling signal of a sampling frequency, a converter (150) for converting the mixed light signal into a digital signal synchronized with the sampling signal, a waveform adjuster (161) for adjusting a waveform distortion of the converted digital signal, a phase adjustor (162) for adjusting a phase of the digital signal adjusted by the waveform adjustor, a demodulator (163) for demodulating the digital signal adjusted by the phase adjuster, and a phase detector for detecting a phase of the digital signal adjusted by the phase adjuster, and a control signal output unit for outputting a frequency control signal on the basis of the detected phase signal to the second oscillator (140).