机载双天线InSAR对飞数据处理与分析

Antiparallel Aspects of Airborne Dual-antenna In SAR Data Processing and Analysis

干涉合成孔径雷达(In SAR)技术具有高精度的地形测绘能力。然而在山区地形条件下,受SAR侧视成像的影响,存在较多的几何畸变区域,干涉相位表现为不连续或者缺少有效信息的情况,对单一的干涉图像对处理难以得到精确的数字高程模型(DEM)。融合两个或多角度的干涉数据可以用于解决这一问题。该文根据这一思路利用机载双天线In SAR对飞数据进行实验,针对山区地形条件下参考高程近似影响运动补偿精度的问题提出了基于高程迭代的运动补偿方法,对于阴影、叠掩区域容易导致相位解缠误差的问题提出基于地形特征的相位解缠方法,从而尽可能降低单一角度数据的DEM误差,以达到消除对飞数据重叠区域3维定位不一致的目的,拼接实验结果验证了处理方法的有效性。

Interferometric Synthetic Aperture Radar（InSAR） is a powerful technique for precise topographic mapping. However, owing to the side-looking SAR imaging geometry, geometry distortions appear in mountainous scenarios. Because of phase discontinuities or the absence of a valid phase, it is difficult to recover accurate DEM in such areas with single-aspect In SAR data. Fusion of two or more different aspects of In SAR data can deal with this problem in practice. Experiments using two antiparallel aspects of airborne In SAR data are carried out based on this idea. To decrease the processing error in single-aspect data and fuse them seamlessly, a MOtion COmpensation（MOCO） method using iterative DEM is used to reduce the MOCO error. Besides, phase-unwrapping methods based on terrain characteristics are proposed to avoid phase-unwrapping error owing to phase discontinuities in areas of shadow and layover. Experimental results verify the effectiveness of the processing methods.