Due to multipath (MP) scattering, many special phenomena and details about the targets in high-resolution synthetic aperture radar (SAR) images are hard to understand. In this letter, a more elaborate improved model combined with the synthetic aperture progress is presented, to analyze the MP scattering. We explore the defocusing and displacement phenomena of MP scattering through signal modeling and time–frequency relationship analysis. The theoretical equations for the displacement of double scattering are derived, and the equation of phase error which causes the defocusing is also given. The SAR raw data simulation of MP scattering and range-Doppler (RD) imaging results validates the correctness of the analysis. From the equations, the effects of MP scattering of different height and different orientation angle in high-resolution SAR images are given. Finally, based on the simulation results, the new interpretation about the relationship between the moustache effect in high-resolution TerraSAR-X SAR images and the height of the structure is obtained.

中文翻译：

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高分辨率SAR图像多径散射效应分析

由于多径（MP）散射，高分辨率合成孔径雷达（SAR）图像中目标的许多特殊现象和细节难以理解。在这封信中，提出了一个更精细的改进模型，结合合成孔径进展，来分析 MP 散射。我们通过信号建模和时频关系分析探索 MP 散射的散焦和位移现象。推导出了双散射位移的理论方程，并给出了引起散焦的相位误差方程。MP散射和距离多普勒（RD）成像结果的SAR原始数据模拟验证了分析的正确性。从方程，给出了高分辨率SAR图像中不同高度和不同方位角的MP散射的影响。最后，基于仿真结果，对高分辨率TerraSAR-X SAR图像中的胡子效应与结构高度之间的关系进行了新的解释。