| 摘要 |
PURPOSE:To obtain a high multiplication factor without increasing a mean output of an exciting light source by constituting a titled amplifier of a light source for generating a digital signal light of a prescribed bit rate, a light source for generating an exciting light which is subjected to an amplitude modulation by a higher frequency than the bit rate, and an optical fiber for transmitting an emitted light of a multiplexer for multiplexing the signal light and the exciting light. CONSTITUTION:A digital signal light 11 from a signal light source 1 and an exciting light 12 from an exciting light source 2 are multiplexed by a multiplexer 3 and are made incident to an optical fiber 4. In this case, wavelength of the exciting light 12 is set to a value which is capable of amplifying the signal light 11 by a nonlinear optical effect in the optical fiber 4. The signal light amplified in this way is emitted from the optical fiber 4, and thereafter, is received by a photodetector. The exciting light 12 is brought to amplitude modulation by a higher frequency than a modulation frequency (bit rate) of the signal light 11. For the purpose of this amplitude modulation, a high frequency modulating device 5 is connected to the exciting light source 2. According to such a constitution, in case when mean power of the exciting light 12 is made the same, a remarkable magnifying factor G and an increase effect are obtained, comparing with the case of continuous excitations. |
