An anisotropic feature extraction method based on space-wavenumber distribution for circular SAR

Circular synthetic aperture radar (CSAR) can provide high-resolution image. The anisotropic scattering information is mapped on the 2D image during the imaging procedure, which degrades imaging quality and causes information loss. In this paper, a multidimensional scattering function estimation method is proposed to extract the anisotropic information, including amplitude varying and scattering center's migration, in CSAR. This method proposed is based on the space-wavenumber distribution (SWD) theory. The Wigner Ville Distribution (WVD) based SWD suffers from serious cross-terms. Therefore, Choi-Williams Distribution (CWD) based SWD is used to process the data. The results of GOTCHA CSAR data validate the efficiency of the proposed method, which outperforms the traditional subaperture-based method in anisotropic feature extraction.