Low-frequency diffraction by a planar junction of a metallic and a wire-mesh halfplane

The canonical problem of an electromagnetic field incident on a metallic halfplane joined to a wire-mesh halfplane is considered. It is assumed that the wire radius is small in comparison with the spacing between the wires, and that this spacing is small with respect to the free-space wavelength. Under this hypothesis, it is shown that the problem can be solved in closed form by using a Wiener-Hopf technique for any nonuniform electromagnetic incident field. The field transmitted through the structure is computed, considering as uniform sources both TE and TM incident planewaves