Abstract:This paper proposes an adaptive UKF algorithm for GNSS/SINS integrated navigation system, aiming at the lack of adaptive adjustment ability of UKF algorithm to measurement noise anomalies. Firstly, this paper carries out the nonlinear modeling of GNSS/SINS integrated navigation system. Then, based on the variational Bayesian principle, the prediction model of measurement noise variance is introduced in the process of time update and measurement update of UKF algorithm. Finally, the GNSS/SINS integrated navigation system based on this adaptive UKF algorithm is simulated and verified. The results show that the proposed algorithm can accurately track the sudden change or slow change of the measurement noise variance in real time, and obviously improve the accuracy of the integrated navigation system compared with the classical UKF algorithm.