Suppression of Self-Noise and Environmental Disturbances by Fusion in Fiber-Optic Gyroscopes for Precision Measurement

We present a study of noise suppression by fusion in fiber-optic gyroscopes based on the source-sharing architecture. A theoretical model is proposed for the detailed analysis of the noise mechanism. The importance of the modulation parameters is revealed, and the optimal modulation strategies are given. Through simulations and experiments, we demonstrate that the proposed fusion scheme not only suppresses self-noise including relative intensity noise (RIN) and thermal phase noise (TPN), but also achieves complete elimination of environmental disturbances. Up to 5.8-fold suppression of self-noise and 5.2-fold reduction of bias instability (BI) is obtained in the experimental apparatus when compared with the performance before fusion. In the applications of fiber-optic gyroscopes for precision measurement, the proposed schemes effectively suppress the noises at the system level.