Influence of external electrooptical modulator biasing on gain and nonlinear distortions in analog fiber-optic links

The dependences of gain and nonlinear distortions in analogue fiber-optic links on bias of an external electrooptical modulator were investigated. The increase in the gain by up to 5 dB as compared with the conventional quadrature point operation was demonstrated by shift the bias voltage applied to the external electrooptical modulator to a low transmission. Dependences of nonlinear distortions on the bias voltage of an electrooptical modulator were investigated. A minor increase in nonlinear distortions (less than 0.5 %) was observed at the conditions of a maximum gain. Proposed theoretical model is in a good agreement with the experimental data.