| 摘要 |
PURPOSE: An optical amplifier for a wavelength division optical transmission apparatus is provided to increase the ratio of signal to noise of optical link since an attenuator for attenuating input in a section having a low loss of optical fiber, is needless and input of optical amplifier is capable of being increased, thereby improving the efficiency of a system. CONSTITUTION: An input monitor part(100) having a first tap coupler(12), an optical splitter(13), a variable optical filter(14) and a function generator(15), is configured. A controller for a voltage controlled variable attenuator(200) having a plurality of photoelectric converters(PD1,PD2), a first comparing part(17), a counter(17), a first averager(19) and a second comparing part(20), is configured. A voltage controlled variable attenuating part having a first amplifier, a VCVA(Voltage Controlled Variable Attenuator), and a second amplifier, is configured. An output monitoring part(300) having a second tap coupler, and a photoelectric converter(PD3), is configured. An output controlling part(400) having a second averager(25) and a third comparing part(26), is configured. |
