Patent ID: 6747792
Filing Date: 2004-06-08
Classification: H01S,H04B,H04J

Abstract:
A method of amplifying a signal light comprising the steps of:initially multiplexing a signal light and a pumping light from a pumping light source so as to output the signal light and the pumping light; initially amplifying the signal light by utilizing the pumping light and providing an output of amplified signal light; receiving the amplified signal light and the pumping light and initially demultiplexing so as to separately output the amplified signal light and the pumping light; receiving the amplified signal light and modifying a waveform of the amplified signal light so as to compensate for waveform distortion of the signal light along a transmission path of the signal light and providing an output of a waveform modified signal light; secondarily multiplexing the waveform modified signal light which is received and the pumping light which is received so as to output the waveform modified signal light and the pumping light; secondarily amplifying the waveform modified signal light by utilizing the pumping light and providing an output of amplified waveform modified signal light so that a reduction of optical signal level due to loss caused by compensation for the waveform distortion of the signal light is suppressed; receiving the amplified signal light and the pumping light and secondarily demultiplexing so as to separately output the amplified signal light and the pumping light; receiving the amplified signal light and modifying a waveform of the amplified signal light so as to compensate for waveform distortion of the signal light along a transmission path of the signal light and providing an output of a waveform modified signal light; thirdly multiplexing the waveform modified signal light which is received and the pumping light which is received so as to output the waveform modified signal light and the pumping light; and thirdly amplifying the waveform modified signal light by utilizing the pumping light and providing an output of amplified waveform modified signal light so that a reduction of optical signal level due to loss caused by compensation for the waveform distortion of the signal light is suppressed.