Analysis of ground wave diffraction by a discontinuity of a planar impedance surface

In this study, we have derived the asymptotic solution for the ground wave propagation over the land-to-sea mixed-path by applying the aperture field method. We have assumed that both the transmitting and the receiving antennas are placed at the heights sufficiently larger than the wavelength. By comparing with the reference solution calculated numerically, the validity of the asymptotic solution is confirmed. By comparing also with the mixed-path theory and the experiments, it is shown that the aperture field method can be applied to the problem of the ground wave propagation over the land-to-sea mixed-path.