Construction of dyadic Green´s functions for ideally soft and hard planes using image sources

Soft and hard boundary conditions allow a polarization independent, device design in electromagnetics. The independence on the polarization can only be established for a single projection of the propagation vector on the surface. The soft and hard properties are commonly synthesized using corrugations or metallic strips on a dielectric surface to implement the desired anisotropic behaviour. The space between the metallic strips or between the metallic ridges of a corrugated ideal surface are approximated as PMC strips for a given frequency range. the strip metallization is treated as a PEC. The "finite width PEC-PMC strip surface" is a quite accurate model but it requires elaborate analytical techniques to be applied. An infinite ground plane consisting of infinitely small PEC and PMC strips is considered in the present paper.