许致火,李恒超
XU Zhihuo,LI Hengchao

• 1:南通大学交通与土木工程学院
• 2:西南交通大学信息科学与技术学院

摘要(Abstract)：

理解相干斑机理、建立物理表征模型是理解合成孔径雷达（synthetic aperture radar,SAR）图像的理论依据。随着SAR技术水平不断发展，图像分辨率也不断提高，其相干斑发生了由完全发展到不完全发展的根本变化。文章分析了SAR图像分辨率以及分辨单元内散射体个数，总结了高分辨率SAR图像相干斑模型研究进展，介绍了近些年代表性SAR相干斑抑制方法，展望了未来相干斑研究的一些趋势，为提升高分辨率SAR图像质量后续研究提供一定的参考。
Understanding the speckle mechanism and modelling the physical representation is the theoretical basis for understanding synthetic aperture radar(SAR) images. As SAR technology continues to develop, the resolution of image increases, and its speckle undergoes a fundamental change from fully developed to non-fully developed. This study first defines the resolution of SAR images and equivalent number of scatters within the resolution cell, outlines the progress of research on speckle models for high resolution SAR images, introduces representative SAR speckle suppression methods in recent years, presents some future research trends, and therefore provides some reference for future research on enhancing the quality of high-resolution SAR images.

关键词(KeyWords)： 合成孔径雷达图像;高分辨率;相干斑;相干斑抑制
synthetic aperture radar images;high resolution;speckle;speckle suppression

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金面上项目（61871335）;国家自然科学基金青年科学基金项目（61801247）;; 南通市民生科技计划重点项目（MS12022005）

作者(Author): 许致火,李恒超
XU Zhihuo,LI Hengchao

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