MODULATION LIGHT-SIGNAL GENERATING SYSTEM

摘要

PURPOSE: To obtain in particular a modulated optical signal generating method and a device in an optical fiber communication system, using the sub-carrier wave of a radio frequency or a microwave frequency. CONSTITUTION: This is a modulated optical signal generation system, and the variety of currents obtained by detecting an optical signal based on the combination of an optical signal, an amplitude modulated input signal, and an optical signal appearing in a feedback circuit is overlapped on the DC bias currents of a semiconductor laser 1 related with an optical/electric feedback circuit 2 having delays. A laser output signal is amplitude-modulated by a frequency equal to the modulation frequency f2 of the input signal by the proper selection of the modulation frequency f2 of the input signal and a low frequency gain B of the feedback loop 2.