提出了一种新的基于小波变换对高分辨率合成孔径雷达图像相干斑噪声抑制的算法。首先从SAR图像相干斑噪声产生的机理出发，论述了通过传统的滤波方法在抑制高分辨率SAR图像的相干斑噪声时，损失了大量的边缘信息和纹理细节而采用小波变换降噪的优越性和必要性；其次论述了在小波域中如何利用高频局部的统计特性和分解尺度大小来选取滤波窗口尺寸进行滤波；最后通过实验结果说明了该方法比采用传统的固定窗来实现对高分辨率SAR图像的降噪、保留边缘信息和纹理细节有着更好的性能。

This paper mainly deals with a new speckle reduction algorithm for high resolution SAR images based on wavelet transform. First of all, the mechanism of generating speckle in SAR image is explained. Then why a great deal of edge and texture were damaged when the speckle of high resolution SAR images were reduced by some traditional methods is discussed, and the advantage and the necessity of speckle reduction based on wavelet transform for reducing speckle are shown ; Secondly, it is expounded in detail how to select the size of a filter window basing on local statistics in each subband and the scale of decomposition for reducing speckle noise, in wavelet transform domain; Finally, Experimental results show that proposed method has better reducing speckle and edge preservation performance over the conventional filter with a window of fixed size.

TN958