单层和多层有缝金属板电磁波透射的FDTD分析

FDTD analysis of transmission through slits on single and stacked conducting plates

采用在入射波一侧的总场边界处同时引进入射波和反射波作为激励源的FDTD方法来分析斜入射时单层和多层有缝金属板电磁波透射问题。通过计算金属板缝隙附近的散射场 ,提取缝隙口径面上的等效面磁流 ,进而得到透射截面。计算机仿真结果证实了算法的有效性。数值计算结果表明 ,两金属板上所开缝隙的相对偏移以及两板间插入介质板将会改变屏蔽效应。该方法可以有效分析平面波斜入射时多层金属板上任意形状缝隙的散射和透射 ,包括缝隙内或金属板之间填充有介质情形。

In this paper, the transmission through slits on single and stacked metallic plates of finite thickness with a plane wave incident at an arbitrary angle is analyzed by using the finite-difference time-domain (FDTD) method with two driving waves, i. e. the incident wave and reflected wave. The field distribution near the slits with magnetic surface currents on the aperture of the slit is calculated, and then the transmission cross sections of slits are obtained. The computed results demonstrate the efficiency of this method. It can be observed that an off-alignment shift of two slits and an inserted dielectric plate between two plates may effectively influence the wave transmission. The proposed method is also available for analyzing the scattering and transmission by slits with different shape and location, including dielectric media filled in multiple metallic plates illuminated by a plane wave at an arbitrary angle of incidence.