2D FDTD simulation of LEMP propagation considering the presence of conducting atmosphere

In this paper, we have computed vertical electric field Ez, and azimuthal magnetic field Hφ at different distances from the vertical lightning channel using the finite-difference time-domain (FDTD) method in the 2D cylindrical coordinate system. The presence of conducting atmosphere up to 110 km above ground level was considered. The fields are computed on the ground surface at distances ranging from 50 to 500 km. One-hop and two-hop skywaves (reflections from the ionosphere) were identified in computed waveforms and used for estimation of apparent ionospheric reflection heights.