Novel fiber optic gyroscope using polarization analysis for rotation rate extraction (Conference Presentation)

Abstract

A new mechanism for extracting rotation rate information by analyzing the polarization of light exiting from a Sagnac loop is reported. Unlike in an interferometric fiber optic gyroscope (I-FOG), here the counter-propagating waves in the Sagnac loop are orthogonally polarized at the loop exit and cannot directly interfere with each other. We show the phase difference between the counter propagation waves can be obtained by the Stokes parameters s2 and s3 of the combined waves. We build such a proof-of-concept polarimetry FOG and achieved key performance parameters comparable to those of a high-end tactical-grade gyroscope. In particular, the device shows a bias instability of 0.09°/h and an angular random walk of 0.0015°/√h, with an unlimited dynamic range. This new approach eliminates the need for phase modulation required in I-FOGs, enabling the development of low-cost FOGs for price-sensitive applications, such as autonomous and robotic vehicles.