Interferometric fiber optic gyro using polarization maintaining fiber

An open loop interferometric Fiber Optic Gyro (IFOG) has been designed,developed,tested and demonstrated at LEOS.This Gyro is of all fiber construction,using polarisation maintaining components, an integrated optic phase modulator and a superluminescent diode as light source. The interferometer uses 400m long polarisation maintaining fiber wound in Quadruple configuration on a 100 mm diameter Aluminium former. The coil and former weight 400 gms. An inhouse built processing electronics, consisting of a Lock-in-Amplifier, superluminescent diode driver with photodiode feedback, a Thermoelectric cooler controller for wavelength stabilization, a pulse suppression logic and regulated power supplies have been used for meeting signal processing requirements. The total power consumption of Gyro is 5 watts. Weight (including all electronics and sensor) is 1.5 Kg. Gyro drift was measured to be 0.07 deg./hr. and random walk 0.006hr. Scale factor stability was 200 ppm.