用TLM法模拟二维三维电磁散射近场和远场

Near-Field and Far-Field 2D and 3D Scattering Simulation Using TLM Method

数值模拟二维等腰直角三角形导电柱体和三维方形导电柱体对高斯脉冲平面波的电磁散射近场和远场分布。数值结果表明在三角柱体的电磁散射近场中镜面反射并不明显 ,但在远场却非常明显并且成为最主要的散射方向。三维电磁散射的数值结果表明 ,二次辐射是电磁散射的主要机理。并且在多个导体目标情况下 ,各自的散射场将互相干涉形成总的散射场。

The scattering near-fields of 2D isosceles-re ctangular-triangle cylinder and 3D square cylinder have been simulated using th e TLM method.Numerical results in 2D case show that the specular reflection is n ot obvious in the near-field scattering ,but it is obvious and is the dominat r eflection in the far-field scattering.Numerical results in 3D case show that th e second radiation is the major mechanism for electromagnetic scattering.Near-f ield scattering images clearly show that when three cylinders exist,the scatteri ng fields from cylinders will interfere mutually.This phenomenon exists in both backward and forward scattering fields,3D results also indicate the similarity a nd symmetry of backward scattering and forward scattering for square cylinder,bu t the field amplitudes are different.