| 摘要 |
PURPOSE:To recognize the wavelength of signal light and to extract light having the wavelength of the signal light independent of the occurrence condition of noise accompanying amplification. CONSTITUTION:The signal light is at first given to a modulator 100, in which modulation is implemented at a prescribed frequency and the modulated light is given to an optical fiber amplifier 200, where the light is amplified. Light outputted from the optical fiber amplifier 200 is given to an optical band pass filter (optical BPF) 300 and a transmission wavelength commanded to the optical BPF 300 by a processing section 600 is selected and outputted. The light outputted from the optical 300 is given to an optical demultiplexer 400, in which the light is demultiplexed into two lights, the one light is given to a photo detector 500, where the light is converted into an electric signal and reported to the processing section 600 as an optical detection signal. The processing section 600 collects the intensity of each modulation component while changing the command transmission wavelength and estimates the wavelength the signal light and the wavelength of the signal light is commanded to the transmission wavelength variable device. |
