指数型分布粗糙地面宽带后向电磁散射的FDTD研究

FDTD research of broadband backward electromagnetic scattering from exponential distribution rough land surface

采用蒙特卡罗方法模拟生成指数型分布粗糙地面,运用时域有限差分方法(FDTD)研究了高斯脉冲波入射时粗糙地面的宽带电磁散射问题。通过数值计算得到不同频率响应对应的后向散射系数,分析了粗糙地面相关长度、高度起伏均方根、土壤湿度和入射角的变化对后向散射系数的影响,得到了指数型分布粗糙地面的宽带后向电磁散射特性。

We simulate exponential distribution rough land surface with Monte Carlo method. We also address wide-band electromagnetic scattering of rough land surface corresponding to Gaussian pulse incident wave by finite-difference time- domain （FDTD） method. Backward scattering coefficients of different frequency response are obtained through numerical calculation. We further analyze the influences of correlation length, root-mean-square of height fluctuation, soil moisture and incident angle variations on backward scattering coefficient. We eventually acquire wide-band backward electromagnetic scattering characteristics of exponential distribution rough land surface.