Patent ID: 7321736

Claim:
An optical receiving station comprising: a filter compensating chromatic dispersion of an optical duo-binary signal received from an optical transmission line with a passing wavelength range; an intensity detector detecting intensity of a specific frequency component of said optical duo-binary signal output from said filter, the intensity being at its greatest value when a total chromatic dispersion value of the optical duo-binary signal output from said filter is at zero; and a wavelength controller adjusting a wavelength of said optical duo-binary signal so that the intensity detected by said intensity detector has the greatest value, and adjusting the passing wavelength range of said filter to pass the adjusted wavelength under a condition of intensity in which the optical duo-binary signal can be received at an optical transmission line without causing a non-linear optical effect and under a condition of receiving wavelength of the total chromatic dispersion in which an eye aperture condition can be equal to or more than a predetermined value.