Optical amplifier control device, optical amplifier control method, optical transmission device, optical amplifier, optical amplifier using band-unit gain equalizer, and wavelength division multiplexing transmission system using band-unit gain equalizer

摘要

A control apparatus comprises a light monitoring unit (10) for dividing a signal wavelength band into at least a band (41, 43) in which output light power of an optical amplifier (1) tends to decrease at an decrease in the number of signal wavelengths and a band (42) including a gain deviation band, and for monitoring inputted light power for the individual divided bands (41,42,43), calculation unit (21) for obtaining the number of signal wavelengths in the individual dividedbands (41, 42, 43) basedon amonitor result, and a target gain correction unit (22) for correcting a target gain based on a result of the calculation. This suppresses a transient variation of signal light level due to SHB or SRS at a high speed with a simple configuration without deteriorating noise characteristic, thus enabling optical amplifiers to be further disposed in a multi-stage fashion, which can lengthen the transmission distance of a transmission system including an optical add/drop unit.