Patent ID: 7466930

Claim:
An optical receiver module comprising: a light receiving element that receives an optical signal and converts the optical signal into an electric signal; an amplifier for amplifying said electric signal; a clock extraction circuit for extracting a clock from the amplified electric-signal; an identification circuit for generating an electric signal for identification from the amplified electric-signal and the clock; a light input power monitor that is connected to said light receiving element and monitors an average value of light power of said optical signal; an input signal amplitude monitor for detecting signal amplitude from said amplified electric-signal; an operation device that is inputted with output of said light input power monitor and output of said input signal amplitude monitor, and thereby outputs an adjusting value of a threshold value of said identification circuit and an adjusting value of a phase of said clock; and a storage device connected to said operation device, wherein: said storage device stores first data indicating a relation between an input signal amplitude before passing through a fiber in a predetermined input power level and a plurality of amplitudes of input signals after passing through fibers at a plurality of dispersion levels, and second data indicating a relation of the optimum adjusting values of the threshold value and the optimum phase adjusting values to waveform distortion levels, and said operation device calculates a difference between an input signal amplitude before passing through a fiber and an input signal amplitude after passing through the fiber by comparing a first output of the light input monitor, a second output of the input signal amplitude monitor and said first data, treats said difference as a waveform distortion level, and obtains an optimum adjusting value of the threshold value and an optimum phase adjusting value by comparing said waveform distortion level and said second data.