Comparison of two theories for buried insulated wire

Two methods of computing the input impedance of buried insulated dipoles are compared. One of them uses the transmission line theory based upon the work of Row. This method, which is valid even in low conductivity soil, could be inaccurate for dipoles short with respect to a wavelength. The other method is a moment method type solution due to Richmond which should be accurate for any geometry. His solution is different from most moment method solutions in that it permits the addition of a thin dielectric layer to any portion of the wire. These two methods were found to be in good agreement for two different wire geometries and a variety of soil conductivities. The only restriction is that segments lengths shorter than allowed by Richmond´s program must be used when the conductivity is high.