In-flight alignment research for airborne INS/GPS based on adaptive unscented Kalman filter algorithm

If there is no small misalignment of in-flight alignment any more, an error model of in-flight alignment is presented under the condition of large misalignment of airborne INS/GPS. An unscented Kalman filter (UKF) algorithm is developed combined with adaptive estimator based on the maximum likelihood estimation criterion. The simulation shows that the estimation of adaptive UKF is not degraded by the inaccurate statistics characteristic of stochastic information, and has a better performance than that of an unscented Kalman filter.