| 摘要 |
PURPOSE:To suppress induction Brillouin scattering by setting the spectrum width of a signal light source and the power of signal pulses from an optical transmission part under specific conditions respectively. CONSTITUTION:This optical transmitter is equipped with a CW oscillation signal light source 12 which is equipped with a frequency modulating means and outputs frequency-modulated CW signal light, an external modulator 16 which imposes intensity modulation upon the CW signal light with an information signal and generates the signal light pulses, and a means which sends out the signal light pulses to an optical fiber 2 as a transmission line. Then expressions I hold for the spectrum width nun of the signal light source 12 and the power Ps of the signal light pulses sent out to the optical fiber 2. Here, Pth is threshold input power with which the induction Brillouin scattering is caused on the transmission line optical fiber when the frequency modulation is not imposed, nuB is the Brillouin gain band width of the optical fiber for transmission, and nuS is the signal light source spectrum when the frequency modulation is not imposed. |
