Fiber-optic interferometric sensor arrays with freedom from source phase-induced noise

We propose arrays of all-passive remote sensors with freedom from both source phase-induced intensity noise and cross talk between sensors. These arrays employ high-duty-cycle time-domain addressing, utilize laser diodes, and have downlead insensitivity. A synthetic heterodyne demodulation technique is used to prevent environmentally induced signal fading. An experimental all-fiber implementation of a single remote sensor yielded a measured sensitivity of below 40 µrad/√VH-z at signal frequencies above 600 Hz.