根据粗糙面基尔霍夫小斜率近似研究了脉冲波入射时实际海谱分布的一维分形海面的电磁散射. 分析了毫米波入射时不同分维、入射角和入射中心频率下双频散射截面的散射角分布. 结果表明分形海面的双频散射截面在镜反射方向有最大的相关带宽,随着海面分维的减小、入射中心频率和入射角的增加,该相关带宽是增大的. 对于入射功率为δ函数时的散射波功率是一个具有一定脉冲展宽的散射脉冲,且脉冲展宽与相关带宽成反比关系.

Based on the Kirchhoff approximation for the rough surfaces with small slopes, the electromagnetic scattering from the one dimensional fractal sea surface with the actual spectrum of the sea is studied by the pulse beam wave incidence. The distributions of the two frequency scattering cross section with different fractal dimension, incident angle and the center frequency are analyzed with millimeter wave incidence. The numerical result shows that there exists the largest coherence bandwidth for the two frequency scattering cross section at the specular direction. The coherence bandwidth will increase with decreasing the fractal dimension and with increasing the incident angle and the center freqquency. It also shows the scattering power which is a pulse shape but with a pulse broadening for the incident power being δ function, this pulse broadening is inversely proportional to the coherence bandwidth.