Transient electromagnetic field generated by a vertical electric dipole on the surface of a dissipative earth

Abstract

The problem of electromagnetic pulse propagation over a dissipative earth surface, excited by a vertical electric dipole located on the earth surface, is investigated. By deforming related integrals in the complex frequency domain it is shown that the scattering contribution of the earth, which is formally expressed in terms of several double infinite integrals, can be efficiently computed from some single finite integrals and is amenable to physical interpretation. Dispersion of electromagnetic waves eminating from an impulse current is presented as a function of both the observation distance and the earth conductivity.