A Unified Modeling Approach of Stochastic Error in Fiber Optic Gyro and Application in INS Initial Alignment

A unified model is developed in this paper to characterize multiple stochastic errors in fiber optic gyro (FOG). Differential equations to characterize different stochastic errors in FOG are derived and an equivalent relationship is proved. The unified model of the multiple stochastic errors in FOG is derived by using the differential equations of individual stochastic errors and the equivalent relationship. The derived stochastic error model is used in the initial alignment of a self-designed FOG inertial navigation system (INS). The experimental test results are compared with those of using the normal White-Noise model and Gauss-Markov model, which has shown the better performances of the proposed modeling approach.