Multilayer frequency selective structure with miniaturized unit cell and ultra wide stopband

In this paper, a multilayer bandpass frequency selective structure (FSS) with miniaturized unit cell and ultra wide stopband is presented. The proposed structure is made up a multilayer printed circuit board with a number of via holes, which can construct stepped-impedance resonators. The operating principle is briefly explained by analyzing the electric field distributions and parametric studies. Simulation results indicate that the size and thickness of a unit cell are 0.07λ₀×0.05λ₀×0.1λ₀ and the bandwidth of the upper stopband is from 7.5GHz to 33.5GHz (|S21| below -20 dB).