The diffraction of radio waves by the curvature of the earth

Abstract

This paper gives a simplified approximate derivation of the field at moderate heights and distances due to an oscillating electric dipole at moderate height above the earth, taking into account the curvature and electrical constants of the earth. The method applies to both vertically and horizontally polarized waves. It is closely connected with treating the earth as flat, the propagation of the waves being curved upwards. In this way the expansions in Legendre functions can be replaced by Fourier integrals, which are simpler to handle. The results of previous workers are reproduced, but are obtained more directly in a form suitable for easy computation.