二维线性与非线性海面电磁散射特性比对研究

二维线性和非线性海面模型与低阶小斜率近似（small slope approximation, SSA）法相结合，对比研究了不同海面的统计特征及其电磁散射特性。研究表明：非线性海浪比相应的线性海浪具有更尖锐的波峰和更为平坦的波谷，虽然其高度均方根保持不变，但斜率变大，且偏离高斯分布；相应地，非线性海面归一化雷达散射截面（normalized radar cross section, NRCS）在远离镜面反射方向上略高于线性海面的NRCS，其后向散射系数也有所提高，并且该差异在小擦地角下更为显著。

Comparative study of electromagnetic scattering from two-dimensional linear and nonlinear sea surfaces

The two-dimensional linear and nonlinear sea surface models combined with the first-order small slope approximation (SSA) method are used to comparatively study the statistical properties of the two surfaces and their radar electromagnetic scattering characteristics. Computational results show that the nonlinear waves have sharper wave crests and shallower troughs than those of the corresponding linear waves. The root mean square of height remains unchanged, but the slopes are increased and depart from the Gaussian distribution. As a consequence, he bistatic normalized radar cross section (NRCS) calculated from nonlinear surfaces is slightly larger than its linear surface counterpart for the scattering angles departing from the specular direction, and the nonlinear surface backscattering coefficient increases. This discrepancy becomes greater for small depression angles.