基于MEKF的卫星姿态确定精度影响因素分析

Influence factor analysis on accuracy of satellite attitude determination based on MEKF

乘性扩展卡尔曼滤波(multiplicative extended Kalman filter,MEKF)方法是卫星姿态确定中最为成熟有效的方法之一。针对该姿态确定方法,采用EKF随机稳定性分析理论,定性地分析了MEKF姿态确定精度的影响因素及其影响情况,重点分析了星敏感器采样频率、卫星姿态角速度的大小、初始误差、滤波参数选取等因素对MEKF姿态确定精度的影响,并通过仿真实验验证了上述分析的合理性。上述研究不仅能够加深人们在理论上对MEKF姿态确定方法的认识,也能够为工程上利用MEKF进行姿态确定提供参考。

The attitude determination methods,which employ the multiplicative extended Kalman filter（MEKF） technique,is effective and widely used in real applications.The theory of stochastic stability of the discrete-time extended Kalman filter is employed to discuss the contributions of factors that take great influence on the accuracy of attitude determination.The factors are mainly considered as follows： the sampling frequency of star-sensor,angular rate,initial error and filtering parameters.Finally,the simulation experiments validate the effectiveness of former analysis.This work is not only helpful to understand the MEKF attitude determination method in theory,but also useful to the practical applications.