Development of a lumped constant type optical modulator in the microwave band for digital terrestrial TV broadcasting

This article describes development and construction of an evolutional lumped constant type LiNbO3 optical modulator that operates via a faint signal in the microwave frequencies for TV program transmission of terrestrial digital TV broadcasting with a bandwidth of 6-9 MHz. This modulator modulates a light beam at 1.5 mum with OFDM (orthogonal frequency division multiplex) signals at a 6-7 GHz band and a voltage level of 60 dBmuV from a receiving antenna. Performance was satisfactory.