基于G-TF/SF技术的地面HEMP环境研究

Study on HEMP Environment of Ground Based on G-TF/SF Technique

对于半空间问题的时域有限差分方法(FDTD)解决方案,基于传统总场散射场(TF/SF)技术的平面波加载方法无法直接用于地面电磁散射问题中,本文将广义总场散射场(G-TF/SF)方法推广至三维地面的高空电磁脉冲(HEMP)环境计算,四周采用卷积完全匹配层(CPML)吸收边界条件。G-TF/SF方法可有效消除数值计算中截取无限大地面产生的边缘效应,提高地面电磁环境的计算精度,且G-TF/SF边界只需要加载入射场,避免了反射场与透射场的计算。

For the finite-difference time-domain(FDTD)solution of the half-space problem,the conventional total-field/scattered-field(TF/SF)technique cannot be directly applied to introduce excitation fields for electromagnetic scattering from the ground.In this paper,we extend the generalized total-field/scattered-field(G-TF/SF)method to accurately calculate the high altitude electromagnetic pulse(HEMP)environment in 3D ground scenarios and adopt the convolution perfectly matched layer(CPML)absorption boundary condition around it.The G-TF/SF method effectively eliminates edge effects in numerical calculations for finite ground,thereby improving accuracy in the calculation of the ground electromagnetic environment.Moreover,only the incident field needs to be introduced at the G-TF/SF boundary,avoiding the computation of reflected and transmitted fields.