| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical transmitter and the like capable of suppressing deterioration in reception sensitivity due to intercode interference in an optical receiver which is caused by generating level fluctuation of an optical signal because a light source is modulated by a low-frequency signal, when an optical signal having a widened optical spectrum is outputted from an optical transmitter to suppress stimulated Brillouin scattering. <P>SOLUTION: The intensity of the output light of a light source 1 is modulated with a low-frequency signal from a low-frequency oscillator 2, this output light is modulated with an information signal in an external modulator 4 and is transmitted to an optical fiber amplifier 15. A signal synchronized with the low-frequency signal or a signal synchronized with the level variation of a light source modulated by the low-frequency signal is transmitted to the excitation light source 6 of the optical amplifier, the output power thereof is controlled, and an excitation light from an excitation light source is combined with an optical signal to be outputted from an external modulator by a multiplexer 5 and is amplified. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
