Dither-free bias control algorithm for electrooptic modulators operating at low frequencies

A dither-free bias control technique for correcting bias drifts in electro-optic in-phase and quadrature modulators is presented and experimentally verified. The technique eliminates the need to apply a dither signal to the bias electrodes, and instead relies on the effects of the electrical modulation signals on the optical power. It is suited for applications where the modulation signals are of low frequency and would spectrally overlap with a conventional dither signal.