在用极化sAR数据研究极化散射机理时,利用的是大量不同方位观察角度下接收的目标散射数据,但通常极化散射特性随方位角的变化并未被考虑。文中提出利用子孔径分析方法研究极化散射机理。子孔径是在不同的方位观察角度下.对整个场景的响应。用子孔径方法分析高分辨率极化sAR图像,可以突出全孔径中雷达后向散射的瞬时变化.因此可用于各向异性特征和非平稳目标的检测。最后利用丹麦EMISAR获取的L波段极化SAR全孔径图像数据进行仿真验证,提出了一种计算相对标准偏差的方法来检测非平稳目标。
When the polarimetric scattering behavior is studied, a lot of SAR polarimetric data, which arc received under different azimuthal look angle, are employed, but the variation of polarimetric scattering behavior are not taken into accout generally. In this paper, a subaperture analysis method is proposed. Subaperture datasets, which correspond to different observed azimuths, are responses of the whole observed scene. In high resolution polarimetric SAR images, subaperture analysis highlights the temporal changes of radar scatter within the full aperture. Therefore, subaperture analysis method can be applied to detect the anisotropic polarimetric behavior and nonstationary objects. Finally, the full aperture SAR data, acquired by Danish EMISAR at g band, are used to make simulation. A method through computing relative standard difference(RSD) is proposed to detect nonstationary objects.