基于小波变换的SAR图像处理研究

Research on SAR Image Processing Based on Wavelet Transform

合成孔径雷达(SAR)是一种高分辨率有源成像雷达,它以具有一定高度的飞行平台为载体,通过发射机主动发射电磁波并接受目标反射的电磁回波生成二维高分辨率图像,但生成的图像除了易受到相干斑的影响之外,往往包含大量的背景杂波。由于小波变换具有低熵性、基函数选择灵活及多分辨率等特性,因此小波变换能对二维信号杂波产生较好的抑制作用,若将小波变换应用于SAR图像处理将会显著改善成像质量。

Synthetic Aperture Radar(SAR)is a high-resolution active imaging radar.It uses a flying platform with a certain height as a carrier,and generates two-dimensional high-resolution images through the transmitter actively launching electromagnetic waves and receiving electromagnetic echoes reflected by the target.However,in addition to being susceptible to coherent speckle,the generated image often contains a lot of background clutter.Because wavelet transform has the characteristics of low entropy,flexible choice of basis function and multi-resolution,wavelet transform can produce better suppression of two-dimensional signal clutter.If wavelet transform is applied to SAR image processing,it will significantly improve imaging quality.