A miniaturized uniplanar metamaterial-based EBG for parallel-plate switching noise suppression

A novel one-dimensional uniplanar EBG based on transmission-line metamaterials is introduced for parallel-plate noise suppression, and is analyzed using multiconductor transmission-line theory. It is shown that the bandgap arises as the result of the contradirectional coupling of the parallel-plate waveguide mode and a backward coplanar waveguide mode. The concept is illustrated using a fully printed implementation suited to high-frequency applications which exhibits an 83% fractional bandgap.