Propagation of electromagnetic waves near the surface of a half-space dielectric with rough interface

Determination of the field of a small dipole over a half-space dielectric is a classical problem with a well-known solution. It is shown that when both the transmitter and receiver are near the surface, the contribution from surface waves is dominant. In practice, the transmit and receive antennas of mobile units are usually very close (relative to the wavelength) to the ground. The existence of surface roughness may alter the contribution of surface waves drastically. In this case the azimuthal symmetry of the problem may no longer be exploited, and the Sommerfeld solution must be modified significantly. The surface roughness generates an incoherent scattered field which is the source of depolarization. In this paper, the effect of slightly rough surfaces on the radiation of a short dipole is studied.