Finnegan, Henderson, Farabow, Garrett & Dunner, L.L.P.
Device and a method for evaluating an optical amplifier
 An optical amplifier evaluating device has a wavelength multiplex signal light generating section, and an O/E converter, and a frequency discriminating and power detecting device, and a computing section. The wavelength multiplex signal light generating section generates an wavelength multiplex signal light which includes signal lights having different wavelengths and having intensity envelopes modulated by different modulation frequencies which are enough higher than an atom life time in a high energy level or a carrier life time in an amplification medium of an optical amplifier to be evaluated, and supplies the wavelength multiplex signal light to the optical amplifier. The O/E converter converts an output light of the optical amplifier to an electric signal. The frequency discriminating and power detecting section detects signal powers of frequency spectrums which are included in the electric signal and respectively correspond to the modulation frequencies of the signal lights, and detects a noise power of the electric signal at a frequency band which is apart from the modulation frequencies. The computing section determines gains and noise figures of the wavelength multiplex amplification by the optical amplifier based on the signal powers and the noise power wavelength by wavelength. 
Nippon Telegraph and Telephone Corporation Ando Electric Co., Ltd
H H
H04B H04B
inventional inventional
Tohru Masafumi
Mori Koga