Signal processing circuit, signal processing method, optical receiver and optical communication system

摘要: In order to reduce influence of noise due a phase deviation, and estimate an amount compensation with superior accuracy in polarization multiplexing/demultiplexing optical communication system, signal processing circuit includes: frequency deviation estimating unit for which is difference between local light the carrier wave included data corresponds polarizations are generated by mixing plurality waves light, phase-modulated have able be demultiplexed outputting estimated as value; analyzing calculating make rotated so on basis values per data; compensating making correspondingly compensation; each input light; deviation.