Coplanar Stripline Coupled to Planar Double Split-Ring Resonators for Bandstop Filters

Double split-ring resonators (SRRs) have previously been used with coplanar waveguide and microstrip to build bandstop filters (BSFs). This letter for the first time demonstrates SRRs coupled to coplanar stripline (CPS) to demonstrate their use as a BSF. The SRRs are on the same plane as the CPS lines. It is further shown that the orientation (the gap in the ring near the CPS line or on the opposite side from the CPS line) of the SRR affects the resonant frequency and the level of rejection, which is not predicted in the earlier papers.