针对机载合成孔径雷达(SAR)实时成像运动补偿对高精度运动参数的需求,该文提出一种基于捷联惯性导航系统/全球定位系统(SINS/GPS)组合 Rauch-Tung-Striebel (R-T-S)平滑估计的实时运动补偿方案。该方案在实时卡尔曼滤波的基础上,对SAR每一次合成孔径时间段内的滤波结果再进行后向平滑递推,进一步修正滤波结果。仿真试验和飞行成像数据处理结果表明,该方案可以有效提高合成孔径时间段内运动参数的估计精度。
Considering the urgent need of high precision motion parameter for SAR motion compensation in real-time, a motion compensation scheme using the Strapdown Inertial Navigation System/Global Positioning System (SINS/GPS) integrated system based on Rauch-Tung-Striebel (R-T-S) smoothing method is proposed. In this scheme, the Kalman filtering is done firstly and based on this, the backward smoothing iteration is performed for correcting the filter’s results during each synthetic aperture moment. The results of numerical simulation and flight-test data processing show that the scheme can effectively improve the precision of estimates of the motion parameter in the synthetic aperture moment.