3-D Single- and Dual-Polarized Frequency-Selective Rasorbers With Wide Absorption Bands Based on Stepped Impedance Resonator

A 3-D frequency-selective rasorbers (FSR) with wide absorption bands at both sides of the transmission window based on stepped impedance resonator (SIR) is presented and investigated in this article. The proposed FSR features thin thickness, lumped-element-free characteristics. channel constructed from a parallel waveguide SIR to provide path reduce thickness whole structure. filled magnetic absorber band, while meander-line shunt connection used avoid lumped components obtain low insertion loss passband. detailed design concept analysis are illustrated fundamental operating principle demonstrated help an equivalent circuit model (ECM). example provided it exhibits passband 7.1 GHz bandwidth 22.6% for less than 3 dB fractional 128.0% reflectivity -10 dB. Moreover, one dual-polarized also designed analyzed generalize strategy. Both single- prototypes designed, fabricated, measured verify concept. Good agreement can be observed between simulated results.