The induced current in parallel wires over an imperfect ground from an incident EMP

The current that is induced in infinitely long, finitely conducting parallel wires over a finitely conducting plane earth from an incident electromagnetic pulse (EMP) is investigated. Frequency-domain expressions for this current are derived. Time domain results are obtained for the case of two wires at the same height above the earth for several wire spacings and ground parameters. It is shown that the coupling between the wires reduces the induced current compared to the current in a single wire. The low-angle case (θ=6°) gives much larger currents than the broadside case (θ=90°), but the induced current becomes zero when θ=0° (where θ is the grazing angle). The maximum current was <8 kA for all cases; this maximum current occurs for θ between 5° and 9°