Optical transmission and reception system and an optical receiver

An optical signal of an optical transmission part 110 is brought into a high-speed polarization scrambling state by a polarization scrambling part 140, and transmitted to an optical fiber transmission line 150 as the optical signal from an optical transmitter 10. The optical signal passing through the optical fiber transmission line 150 is inputted to an optical receiver 20. The optical signal inputted to the optical receiver 20 is converted into an electric signal by a polarization dependent photoelectric detection part 510. The converted electric signal is inputted to a digital signal processing part 520 having a polarization scrambling cancel part 180 for canceling the polarization scrambling state by a digital signal processing operation. At the digital signal processing part 520, the polarization scrambling state of the electric signal is canceled, and a data signal is outputted.