Design and analysis of angular stable antipodal F-type frequency selective surface with multi-band characteristics

This article presents frequency selective surface (FSS) with multi-band characteristics that features tri band band-stop and dual-band passband filter. The proposed FSS unit cell comprises the F-type resonance elements disposed of antipodal (diametrically opposed to) one to another on both layer and a square loop surrounding all resonators on the top layer of the dielectric substrate. The structure is specifically designed to filter out some extensively used broadband communication signals, such as, WiMAX and WLAN while enabling C-band satellite communication in the earth station and provides three stopbands operating at 2.4, 5.2, and 5.9 GHz besides two passbands of 4.1 and 5.5 GHz. Although this structure has a multi-band structure, it exhibits high stable performance for oblique incidence ranging from 0 degrees to 60 degrees for both transverse electric (TE) and transverse magnetic (TM) polarizations. Considering the resonant frequency deviation (RFD) at the incidence waves with different angles of arrivals, it was found that RFD at 60 degrees is less than 0.6% on average and very low when compared with existing studies about multi-band FSS. The detailed equivalent-circuit model (ECM) is employed to predict and analyze the transmission characteristic of the proposed structure, and a good agreement between the simulated and measured transmission coefficients is obtained.