Patent ID: 8737848

Claim:
An optical receiver comprising: an optical amplifier that amplifies an optical signal fed thereinto according to an operating current fed thereinto, the optical signal being a wavelength-multiplexed optical signal, a demultiplexer that demultiplexes an optical signal output from the optical amplifier; an operating-current control circuit that selects a monitoring target from a plurality of wavelength signals output from the demultiplexer and controls the operating current of the optical amplifier so that optical power of the monitoring target is controlled to be a predetermined value; an optical power detection portion that detects optical power of the optical signal fed into the optical amplifier; and a light-receiving element that receives a plurality of wavelength signals output from the demultiplexer, wherein the operating-current control circuit selects a wavelength signal having optical power larger than average optical power of the plurality of the wavelength signals from the plurality of the wavelength signals as the monitoring target and controls the operating current so that the optical power of the monitoring target is smaller one of a predetermined value in the dynamic range of the light-receiving element and an allowed value of the operating current when the optical power fed into the optical amplifier is larger than a first predetermined value, and selects a wavelength signal having optical power smaller than the average optical power from the plurality of the wavelength signals as the monitoring target and controls the operating current so that the optical power of the monitoring target is larger one of a predetermined value in the dynamic range of the light-receiving element and an allowed value of the operating current when the optical power fed into the optical amplifier is smaller than the first predetermined value.