Dynamical diffraction of microwaves by periodic dielectric media

The properties of microwave diffraction by periodic dielectric media have been treated by extending the theory of dynamical scattering by perfect atomic crystals. The expressions of the form factor and of the structure factor have been obtained, and the conditions and limits of applicability of the two-wave approximation have been discussed. The diffraction pattern in Bragg geometry, the extinction length, the deviation from the Bragg law, and the width of the total reflection range have been evaluated for a two-dimensional periodic medium consisting of a regular array of cylindrical holes made on a polyethylene plane slab. We have reported the results of the experiment carried out to verify the accuracy of the theory. The comparison between theoretical and experimental results has shown good agreement.