| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical transmission apparatus and its control method which can assure communication quality by controlling suitably the intensity of each signal light even in a normal state that there is not loss change of a transmission line or change of the number of multiplexing wavelength or even in an abnormal state that the loss change of the transmission line or the change of the number of the multiplexing wavelength occurs. <P>SOLUTION: The optical transmission apparatus includes a means (31, 41) for detecting the monitored light intensity by separating the monitored light from the received wavelength multiplexing signal light, a means (32, 42) for detecting the wavelength multiplexing signal light after the monitored light is separated, a gain control type optical amplifier 34 for amplifying the wavelength multiplexing signal light, an optical attenuator 35 for regulating the intensity of the amplified wavelength multiplexing signal light, and a monitor controller 20 for controlling so that the optical amplifier always becomes a predetermined gain and controlling so that the output intensity of the wavelength multiplexing signal light becomes a predetermined target value. The monitor controller suppresses the predetermined control of the output light intensity by the optical attenuator when the change of the monitored light intensity falls within tolerance and the change of the signal light intensity separates from the tolerance. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
