Dual-Band Band-Pass Frequency Selective Surface Based on the Matryoshka Geometry with Angular Stability and Polarization Independence

This paper describes by the first time, at least of the authors' knowledge, a frequency selective surface, FSS, based on the Matryoshka geometry, with dual-band band-pass frequency response, keeping the interesting features previously outlined: angular stability and polarization independence. Moreover, it is a single layer FSS and the reduction of the resonant frequencies, a characteristic of the Matryoshka geometry, was maintained. Initial design equations are proposed, providing good results, making easy the design of the FSS for other resonant frequencies and specific applications. Two FSS were designed, fabricated and characterized, verifying a good agreement between numerical and experimental results. The resonant frequencies remain almost constant for different incident angles, from 0 degrees to 45 degrees, confirming the angular stability.