Theoretical and experimental analysis of magnetic inclusions for the realization of metamaterials at different frequencies

In this paper, we propose a theoretical and experimental analysis of different kinds of magnetic inclusions to be used in the synthesis of artificial materials and metamaterials in the microwave and millimeter wave frequency ranges. multiple split-ring resonators (MSRRs) and spiral resonators (SRs) are proposed to achieve miniaturization at microwaves, while labyrinth resonators (LRs) are considered to increase the resonant frequency and avoid miniaturization at higher frequencies. New and accurate analytical models, derived in terms of parallel LC lumped circuits, for a quick design of the three kinds of magnetic inclusions are proposed in the paper. These models are compared to the ones already presented in the literature (when available), showing better accuracy in predicting the resonance frequency of the inclusions. Finally, the proposed models are validated through proper experiments.