用于消除缓变伪距偏差的抗差扩展卡尔曼滤波方法

摘要

Since the slowly growing psendo-range errors existing in the pseudo-range measurements of satellite navigation system may further lead to the decreasing of position accuracy,a robust extended Kalman filter (EKF)method based on sliding and accumulated residuals was proposed.The method based on the robust EKF algorithm cumulated the residual vectors for multi epochs in the sliding window and increased the pseudo-range error of standardized residual vector,which improved the robustness of slowly growing pseudo-range error.Results show that the method can effectively eliminate or weaken the position error caused by slight pseudo-range error and slowly growing pseudo-range error.Compared with the traditional robust EKF algorithm,the positioning accuracy of this method is improved obviously.%针对卫星导航系统中伪距观测量存在缓变伪距偏差，导致定位精度下降的问题，提出了一种基于滑动积累的抗差扩展卡尔曼滤波方法。该方法在抗差扩展卡尔曼滤波算法的基础上，通过滑动窗口内多个历元残差矢量的累积，增大标准化残差矢量的伪距偏差，来提高对缓变伪距偏差故障的抗差能力。仿真表明，该方法能有效消除或者减弱微小伪距偏差和缓慢增长伪距偏差造成的位置误差，与传统抗差扩展卡尔曼滤波算法比较，定位精度得到明显改善。