Transmission line metamaterials based on pairs of coupled split ring resonators (SRRs) and complementary split ring resonators (CSRR): a comparison to the light of the lumped element equivalent circuits

This paper analyzes and compares two types of transmission line metamaterials: (i) coplanar waveguide (CPW) transmission lines loaded with pairs of magnetically coupled split ring resonators (SRRs), and (ii) microstrip lines loaded with pairs of electrically coupled complementary split ring resonators (CSRRs). Both structures are described by lumped element equivalent circuit models rather different. However, both structures exhibit very similar phenomenology, and there is a mapping between the elements of both models that gives identical results for the analytical expressions providing the resonance frequencies (transmission zeros) that these lines exhibit. It is shown that these artificial lines are useful as dual-notched filters and as differential sensors and comparators.