【摘要】 首次采用三维时域有限差分(3D-FDTD)经纬度模型和地理学信息系统技术(Geographic InformationSystem,GIS)对地球-电离层波导系统进行几何建模,并对闪电、舒曼谐振中的极低频/超低频(ELF/SLF)的电磁辐射进行仿真实验。计算结果表明,当激励源放置在高空模拟闪电发生时,电磁波通过波导系统传播到观测点,并继续绕地球多次经过同一位置,直到完全衰减,其谐振频点与舒曼谐振点基本一致。发现地形地貌对于地表电磁波的电场分布有较大影响,而对地表电磁波的磁场分布几乎没有影响。更多还原

【Abstract】 This paper initially combined the three-dimensional finite difference time-domain(3D-FDTD) method with the Geographic Information System(GIS),to simulate the radiation of the electromagnetic(EM) wave of ELF/SLF in the flashing lightning and the Schumann resonance in the Earth-ionosphere waveguide system.When the source was located in the high altitude zone,it was found that the resonant frequencies and the theoretical values of the Schumann resonance were quite close,and the EM wave travelled the observation point several times round the Earth-ionosphere waveguide system before vanishing.We also found the GIS had great influence on the distribution of the surface electric field,however,the magnetic field were not effected.更多还原