基于SVD的R-T-S最优平滑在机载SAR运动补偿POS系统中的应用

 机载合成孔径雷达（SAR）运动补偿用位置姿态系统（POS）的导航精度直接影响SAR成像的效果。为进一步提高POS的导航精度和数值稳定性，提出将基于奇异值分解（SVD）的Rauch-Tung-Striebel（R-T-S）最优固定区间平滑应用于POS后处理中。在基于SVD的前向卡尔曼滤波（KF）的基础上，进行了基于SVD的后向R-T-S最优固定区间平滑，获得位置、速度和姿态的最优估计。该方法将原算法中均方误差阵进行奇异值分解，不仅具有很好的数值稳定性和鲁棒性，而且避免了矩阵的求逆。半物理仿真结果表明，该方法在导航精度和数据平滑度上明显优于目前工程中应用的KF，是一种有效的事后处理方法。

Application of SVD-based R-T-S Optimal Smoothing Algorithm to POS for Airborne SAR Motion Compensation

Position and orientation system(POS) has been used widely to compensate for the motional error of an airborne synthetic aperture radar(SAR),and its navigation precision has a direct effect on SAR imaging.In order to obtain higher navigating precision and numerical stability,an algorithm of Rauch-Tung-Striebel(R-T-S) optimal fixed interval smoothing based on singular value decomposition(SVD) was used in POS.The smoothed best estimate of position,velocity and attitude can be obtained by forward-pass Kalman fi...