Narrowband bandpass frequency selective surface with miniaturized elements

This article presents a bandpass frequency selective surface (FSS) with a narrowband frequency response. The designed FSS is made of miniaturized elements unit cell. The operation principle of the FSS is explained by using an equivalent circuit model, where the passband bandwidth can be controlled by the values of the circuit elements corresponding to the geometrical dimensions of the unit cell. The compatibility of the presented structure in designing higher order narrowband filtering responses is verified by designing a second-order bandpass FSS with 8.5% fractional bandwidth with a center frequency of 2.7 GHz.