Time domain analysis of the horizontal grounding electrode: Antenna theory approach versus transmission line approximation

The paper deals with a transient analysis of a horizontal grounding wire immersed in a lossy half-space by means of a rigorous antenna theory (AT) and an approximate transmission line (TL) approach, respectively. The AT formulation is based on the corresponding space-time Pocklington integro-differential approach. The presence of the earth-air interface is taken into account via the simplified reflection coefficient arising from the Modified Image Theory (MIT). The TL approach is based on the set of space-time telegrapher´s equations. The space-time Pocklington integro-differential equation has been solved analytically while the telegrapher´s equations have been numerically solved via the Finite Difference Time Domain (FDTD) method. The results via different approaches agree rather satisfactorily.