COHERENT SCM OPTICAL TRANSMISSION METHOD AND OPTICAL TRANSMITTER, OPTICAL RECEIVER AND OPTICAL TRANSMISSION SYSTEM USED FOR EXECUTING THE SAME

摘要

PURPOSE: To suppress induced Brillouin scattering and to improve efficiency in the case of using an optical amplifier by generating an optical signal by performing optical modulation according to a multiple signal, and transmitting, signal while suppressing the mate carrier component. ;CONSTITUTION: In an SCM optical transmitter 100, a multiple signal generating means 101 generates the multiple signal, an optical modulating means 102 generates the optical signal by modulating a coherent light source according to the multiple signal or the like, and an optical filtering means 103 suppresses or removes the main carrier component in the optical signal. A local oscillating light source 111 on the reception side outputs the local oscillating light at a frequency in prescribed relation with the frequency of the main carrier component in the optical signal transmitted from an optical transmission line 12, the local oscillating light and the transmitted optical signal are added by a photocoupler 112, the added light is converted to an electric signal by a light receiving means 113, and a signal is selected out of the electric signals, at every channel by a band pass filter 114 and demodulated by a demodulating means 115. Therefore, the total power of the optical signal can be decreased without damaging information transmission.;COPYRIGHT: (C)1993,JPO&Japio