Dual of Defected Ground Structure for Coplanar Stripline

Defected ground structures (DGS) have been used with microstrip and coplanar waveguide (CPW), but until now no comparable structure has been demonstrated for coplanar stripline (CPS), probably because there is no “ground plane.” This letter introduces a dual of DGS for CPS with dual properties, or it acts as a shunt, series RLC circuit that creates an equivalent shunt short circuit at the resonant frequency, which is the dual of the DGS in microstrip or CPW.