地球卫星自主天文导航滤波方法性能分析

在系统硬件精度无法改进的条件下,滤波方法是影响地球卫星自主天文导航精度和实时性的最重要因素,本文针对地球卫星天文导航工程应用的需求,研究了目前导航系统中应用最为广泛的扩展卡尔曼滤波(EKF)、Unscented卡尔曼滤波(UKF)、Unscented粒子滤波(UPF)3种滤波方法,在滤波周期和噪声分布影响下的导航精度和实时性.半物理仿真结果表明,在相同仿真条件下,Unscented粒子滤波方法具有最高的导航精度,但计算量也最大,EKF方法计算量最小,导航精度最低.本文结果可为地球卫星自主导航系统中滤波方法的选择提供参考和依据.

Analysis of filtering methods for satellite celestial navigation

The filtering method becomes the most important factor affecting the navigation accuracy and timeconsumption, whenever the accuracy of sensors can not be improved anymore. In satellite navigation, the extended Kalman filter(EKF), unscented Kalman filter(UKF) and unscented particle filter(UPF) are the three widely used filtering methods. The performance of the system based on these three methods under different conditions is analyzed. Hardware-in-loop tests show that in the same condition, the UPF provides the highest navigation performance but requires the most computation; meanwhile the EKF gives the lowest navigation performance but needs the least computation. The conclusions drown by this study are useful in the design and analysis of autonomous navigation system of satellites.