Cut-off bandwidth of metamaterial-based parallel plate gap waveguide with one textured metal pin surface

This work explores the possibilities of creating stop bands (or bandgaps) for TEM mode in parallel plate waveguides by using artificial surfaces in one of the plates. Particularly, as artificial surface a textured periodic surface made of metal pins has been selected. The present paper reports a parametric study of the ldquoFakir's bed of nailsrdquo structure in terms of the size of the achieved bandgap when the structure is placed within a parallel plate waveguide. Bandwidths larger than 2:1 are seen to be possible. The proposed structure could be used for the design of the new type of waveguides named gap waveguides.