METHOD AND DEVICE FOR OPTICAL MODULATION AND OPTICAL RADIO TRANSMISSION SYSTEM

摘要

PROBLEM TO BE SOLVED: To actualize an optical modulation system which generates no unnecessary wave and to provide an optical radio transmission system which eliminates the need for a band-pass filter. SOLUTION: This system has a 1st driver part which applies a 1st bias voltage to an electric signal of an intermediate frequency band, a 2nd driver part which applies a 2nd bias voltage to a local oscillation signal, a two-branch part which branches an input light signal into two, a 1st optical modulation part which modulates one of the light signals branched by the two-branch part with the electric signal outputted from the 1st driver part, and a 2nd optical modulation part which modulates the other light signal with the electric signal outputted from the 2nd driver part; and at least the 1st bias voltage and 2nd bias voltage are so set that the carrier components that the light signals modulated by the 1st and 2nd modulation parts have are inverted in phase.