The near-field scattering characteristics of rough target are analyzed by using a revised bidirectional reflectance distribution function (BRDF) of a rough surface based on least squares support vector machine (LS-SVM). The revised BRDF is more reliable in a larger range of incident angles and scattering angles that beyond the scope of experimental measurements. The basic principle of LS-SVM and the modeling process are firstly introduced in detail. Then the comparison among LS-SVM, the back propagation neural network (BPNN) and the measured data is carried out．The results show that the LS-SVM model has better integrative performance, stronger generalization ability and higher precision. On this basis, the calculation of the near-field radar cross section (RCS) of a complex target is safely performed and analyzed. The method proposed is helpful to better investigate the near-field scattering characteristics of rough target.
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