Application and Analysis of Central Difference Kalman Filter in Celestial Navigation with Disturbances

摘要

The celestial navigation system is one of the important autonomous navigation systems for spacecraft. And the Unscented Kalman Kilter (UKF), which is suitable for nonlinear system, has been widely applied in celestial navigation. However, when the disturbances exist and the state covariance becomes large, UKF will reduce the accuracy and the rapidity of convergence. This paper proposes to employ Central Difference Kalman Filter (CDKF) in celestial navigation with disturbances. The numerical simulation results show that, the navigation performance by CDF is better than UKF, with the error peak value only 30% of that of UKF. The further analysis also shows that CDKF has low sensitivity to state covariance and therefore has better robustness than UKF in the application of celestial navigation with disturbances.