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Single-layer bandpass frequency selective structure with very wide upper stopband

In this paper, a single-layer bandpass frequency selective structure (FSS) of high selective performance is presented. The proposed structure consists of an array of single-layer printed circuit boards with lumped inductors, which can construct “dual-mode” stepped-impedance resonators. The operating principle is briefly explained by an equivalent circuit model and is verified by parametric studies. Simulation results indicate that the FSS features miniaturized unit cell size, very wide upper stopband, and stable frequency filtering response under a large variation of incident angles.