Resonance and cross-polarization effects in conventional and complementary split ring resonators periodic screens

Frequency selective surfaces made of conventional and complementary split ring resonators (SRR and CSRR) are analyzed theoretically and experimentally. For the theoretical study a surface admittance approach is used, which holds for any arbitrary angle and polarization of a plane wave. This method is based on reported theories about the behavior of single SRR and CSRR. Experimental results in free space are provided in order to check the theory. Good qualitative agreement is observed between theory and experiment, although some quantitative disagreements still remain and need explanation. Application of these devices as frequency selective surfaces and polarization converters could be possible due to the high variety of the resonant and cross-polarization effects seen.