Investigation of the influence of the cell shape and lattice on EBG structures for the effective surface wave suppression

The dispersion diagram represents a powerful tool for the designer since it provides a deep physical insight of the expected performance of EBG structures; a further investigation reveals that different structures, although acting in the same forbidden band, present a different degree of efficiency in reducing the mutual coupling between two antennas. In particular, in this work it will be shown that two mushroom-like EBGs, which differs for the shape of the elements and for the lattice geometry, exhibit a different level of surface waves suppression although they both act in their forbidden band as derived from their dispersion diagram.