Patent ID: 8855503
Filing Date: 2014-10-07
Classification: H04B

Abstract:
1. An optical receiver to receive an optical modulation signal at a pre-established symbol time of two or more levels as the optical signal, and comprising: a coupling type optical delay detection-receiver containing a delay approximately matching the symbol time of the received optical symbol; an AD converter; a differential phase calculator circuit; a phase integration circuit; an optical amplitude detection unit to extract the amplitude component from the optical signal; an optical electric field signal regenerator circuit; and a transmission degradation equalizer to compensate for transmission degradation on the transmission path; wherein the coupling type optical delay detection-receiver includes a delay approximately matching the symbol time of the received optical signal, and detects and outputs the received optical signal, and the AD converter converts the output signal from the coupling type optical delay detector into a digital signal, and the differential phase calculator circuit inputs the digital signal and calculates the differential phase relative to the optical signal of the immediately prior symbol time, for approximately each symbol time, and the phase integration circuit integrates the calculated differential phase that was input with each symbol time of the received signal and calculates the phase information, and the optical amplitude detection unit extracts the amplitude component of the received optical signal, and the optical electric field signal regenerator circuit combines the calculated phase information with the optical amplitude information obtained in the optical amplitude detection unit and regenerates an optical electric field signal, and the transmission degradation equalizer inputs a regenerated optical electric field signal and equalizes the transmission degradation.