脉冲星导航系统的星历表误差RKF校正算法

RKF Method for Pulsar Based Navigation with Emphasis Error Correction

为了减小星历表误差对脉冲星导航系统的影响,本文提出了一种针对星历表误差的RKF(Robust Kalman filter)导航定位方法。通过对星历表误差进行分析,得到星历表误差随时间变化的关系。建立带有星历表误差的量测模型,利用Kalman滤波原理进行计算。在Kalman滤波计算的过程中,星历表误差项是未知的,利用矩阵不等式进行处理,最终确定误差协方差的下界,并计算反馈增益得到最终的状态估计值。将RKF方法与UKF和其他两种处理星历表误差的滤波方法分别在绕飞地球和火星的轨道上进行测试并进行对比分析,实验结果表明,提出的方法可以取得到比UKF和其他两种滤波方法更高的定位精度,有效的减小星历表误差对脉冲星导航系统的影响。

In order to reduce the influence of the emphasis error to the X-ray pulsar navigation system performance, a RKF based method for dealing the emphasis error is proposed, Through analyzing the emphasis error, the relationship between emphasis error and time is obtained. The measurement model with emphasis error is established and calculated with the principle of Kalman filter. The estimation error covariance is dealing with the matrix inequality due to the emphasis error is contained in the estimation error covariance. The proposed RKF method is tested on the Earth and Mars rotation orbit and compared with UKF and other filtering method which can deal with the emphasis error. The simulation results shows the proposed method can achieve higher positioning accuracy than UKF and the other two filtering methods, the RKF based method can greatly reduce the impact of emphasis error for XNAV.