The author presents applications of a numerical solution of the wave equation for radiowave propagation over irregular terrain, based on the parabolic approximation to Maxwell's equations. The novelty of the method resides in its ability to calculate signal strength when both the medium and the boundaries are allowed to have essentially arbitrary structures. It is a full-wave method which allows the modelling of wavefronts of arbitrary shapes, within the constraints of the PE approximation. The finite difference treatment of the air/ground boundary allows the representation of an arbitrary path profile as a sequence of linear segments. The method is valid at all ranges except in the near-field of the antenna, and there are no frequency constraints provided the propagation phenomena to be modelled take place within a few degrees of the horizontal.
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