EM fields of a phased line current over a conducting half-space

The need often arises to predict the electromagnetic field of power and communication lines over the earth. A simple and explicit derivation is given for the electromagnetic fields of a travelling current line source located over a layered conducting half-space. Special attention is paid to the case of a homogeneous half-space where analytical closed-form expressions can be obtained. Of some interest is the radiation of a vertically polarized radio ground wave which would not be present if the line source was uniform