Mode-Matching Analysis of Conductor Backed Coplanar Waveguide With Surface Etching

Conductor backed coplanar waveguide (CPWG) with etching between the metal strips on the surface has been studied using the mode matching technique. The characteristics of the CPWG was first studied and compared to commercial software. The analysis shows that etching few microns from the substrate increases the characteristic impedance by more than 30% for CPWG with small width and small separation and 10% for large width and small separation. This implies that etching can be used as a tool for CPWG design.