介绍一种较为可靠的高分三号合成孔径雷达（synthetic aperture radar，SAR）图像立体定位方法，即便立体像对时空条件差异较大，该方法也能达到较高的定位精度。首先根据斜距多普勒模型建立立体定位方程组，利用多项式拟合法解算卫星状态矢量，最后利用牛顿法求解方程组。利用高分三号卫星在北京、苏州、上海3个地区、成像时间各不相同且分辨率在5 m以内的7景SAR图像进行立体定位实验，以Google Earth上的实际位置为基准，实验得到的所有目标点的平面误差均在30 m内，高程误差均在34 m内，证明即使立体像对成像时间间隔较长，也可以得到精度较高的目标点三维信息，且滑动聚束模式下得到的立体像对定位精度最高。
This paper introduces a reliable stereo positioning method of GaoFen-3 synthetic aperture radar (SAR) images. The method can achieve high positioning accuracy even if the spatial and temporal conditions of the stereo image differ greatly. Firstly, the stereo positioning equations are established according to the range-Doppler model, and then the polynomial fitting method is used to obtain the state vectors of the satellite. Finally, the equations are solved by Newton's method. In this paper, stereo location experiments are carried out with 7 SAR images of Beijing, Shanghai, and Suzhou with different imaging times. The resolutions of these images are within 5 m. Verification based on Google Earth image shows that the plane errors of all the targets are within 30 m, and the height errors are within 34 m. It is proved that even if the imaging time intervals of the stereo SAR image pairs are long, the 3D information with high accuracy can also be obtained. Besides, the localization accuracy of the SAR image pair from spotlight mode is the highest.
[1] 丁赤飚, 刘佳音, 雷斌, 等. 高分三号SAR卫星系统级几何定位精度初探[J]. 雷达学报, 2017, 6(1):11-16.
[2] 张红敏. SAR图像高精度定位技术研究[D]. 郑州:解放军信息工程大学, 2013.
[3] Chen P H, Dowman I J. Space intersection from ers-1 synthetic aperture radar images[J]. The Photogrammetric Record, 1996, 15(88):561-573.
[4] Eldhuset K, Weydahl D J. Geolocation and stereo height estimation using TerraSAR-X spotlight image data[J]. IEEE Transactions on Geoscience and Remote Sensing, 2011, 49(10):3574-3581.
[5] Curlander J C. Location of spaceborne SAR imagery[J]. IEEE Transactions on Geoscience and Remote Sensing, 1982, GE-20(3):359-364.
[6] Wang M, Wang Y L, Run Y, et al. Geometric accuracy analysis for GaoFen3 stereo pair orientation[J]. IEEE Geoscience and Remote Sensing Letters, 2018, 15(1):92-96.
[7] Zhang G, Wu Q W, Wang T Y, et al. Block adjustment without GCPs for Chinese spaceborne SAR GF-3 imagery[J]. Sensors, 2018, 18(11):4023.
[8] Balss U, Gisinger C, Eineder M. Measurements on the absolute 2-D and 3-D localization accuracy of TerraSAR-X[J]. Remote Sensing, 2018, 10(4):656.
[9] Gisinger C, Balss U, Pail R, et al. Precise three-dimensional stereo localization of corner reflectors and persistent scatterers with TerraSAR-X[J]. IEEE Transactions on Geoscience and Remote Sensing, 2015, 53(4):1782-1802.
[10] 马素颜. 基于高分辨率卫星遥感数据提取DEM方法研究[D]. 上海:华东师范大学, 2009.
[11] Sansosti E. A simple and exact solution for the interferometric and stereo SAR geolocation problem[J]. IEEE Transactions on Geoscience and Remote Sensing, 2004, 42(8):1625-1634.
[12] 王琴, 陈蜜, 刘书军, 等. 利用升降轨道SAR数据获取DEM的试验研究[J]. 测绘通报, 2015(6):39-43.
[13] 荆创利. 使用SAR影像生成DEM的方法研究与精度分析[D]. 成都:西南交通大学, 2008.
[14] 喻文健. 数值分析与算法[M]. 2版. 北京:清华大学出版社, 2015.
[15] 尤红建, 付琨. SAR图像精准处理[M]. 北京:科学出版社, 2010:188-189.
[16] 袁修孝, 曹金山. 高分辨率卫星遥感精确对地目标定位理论与方法[M]. 北京:科学出版社, 2012.
[17] 陈尔学. 星载合成孔径雷达影像正射校正方法研究[D]. 北京:中国林业科学研究院, 2004.
