An electric field sensor array using optical coherence modulation of light is proposed here. The system consists of lithium niobate (LiNbO₃) optical coherence modulator acting as electric field sensor. The main characteristics of coherence-modulated transmissions include the need of using broad-band optical sources and integrated optics lithium niobate electro-optic retarders. Coherence-modulated systems have been studied for the last few years as new potential high-speed optical links useful for point-to-point, local area networks, and bi-directional transmissions, at optical wavelengths around 1300 nm. This paper describes the experimental system and characterization of the electro-optic sensor for detection of sinusoidal electric field.