OPTICAL COMMUNICATION SYSTEM

摘要

PURPOSE: To transmit frequency multiplexed electric signals at different levels through an optical fiber with high quality. CONSTITUTION: The electric signal frequency multiplexed by a synthesizer 5 is lightintensity modulated, converted to an optical signal by an electric/optic converter 7, then inputted to an external optical modulator 8. Besides, the external optical modulator 8 applies light intensity modulation to the optical signal supplied from the electric/optic converter 7 while using electric signals frequency multiplexed by a synthesizer 4 and inputs that optical signal to an external optical modulator 9. On the other hand, the external optical modulator 9 applies light intensity modulation to the optical signal supplied from the external optical modulator 8 while using the electric signals frequency multiplexed by a synthesizer 6 and inputs that optical signal to an optical fiber 3.