Application of the Scaled Unscented Kalman Filter with Augmented State in the Fiber Optic Gyroscope

AbstractThe interferometric fiber optic gyroscope (IFOG) is a nonlinear response system. The noise, which results from the optic and electrical parts of the gyro for the environmental disturbance, includes both nonlinear noise and additive noise, and degrades the bias stability of the gyro. In this paper, the nonlinear state equation about the closed-loop IFOG is deduced from analyzing the sources, characteristic and effect of noise, and then the scaled unscented Kalman filter (SUKF) with augmented state is presented to reduce the noise. The experiment showed that: by adjusting SUKF parameters, it evidently decreases the standard deviation and Allan variance of the bias stability. Therefore this algorithm achieves better performance of filtering and improves effectively the bias stability of the gyro