OPTICAL FIBER SYSTEM USING POLARIZATION MULTIPLEXING FOR SUPPRESSING STIMULATED BRILLOUIN SCATTERING

摘要

PROBLEM TO BE SOLVED: To provide an optical fiber transmission system which uses polarization multiplexing of a pump signal for reducing the influence of a stimulated Brillouin scattering(SBS) as for an optical fiber transmission system whose SBS is low. SOLUTION: A technique for suppressing the stimulated Brillouin scattering(SBS) in an optical fiber signal path divides power of emitted (signal) into (signals in) a polarization state by using polarization modulation at the place of a transmitter. By reducing the power of each polarization, the SBS is reduced. The line width of a light source is expanded by (1) introducing incoherence property between the polarization state (by introducing time delay into one of the signal paths in a polarization state) and (2) introducing a frequency shift between the polarizing state (by providing an acoustic optical modulator(AOM) within the signal path of the remaining polarization state).