Closed-Loop Interferometric Fiber-Optic Gyroscope with Unpolarized Light

This article deals with utilizing special techniques to improve parameters of interferometric fiber-optic gyroscope (I-FOG) using unexpensive single-mode (SM) fiber and based on all-fiber components. Firstly, it was shown that polarizer must be used to compensate for depolarizing unperfections. Optimization of Er-doped superfluorescent fiber source (SFS) greatly increased SNR of the sensor. Finally, solution for closed-loop operation with slow piezoelectric phase modulator was found yielding significant extension of measurement range as well as its linearity