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

This dissertation 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. This structure is designed to be used as a frequency selective filter in the earth station performing satellite communication within the scope of a project. The design provides three stop-bands operating at 2.4 GHz, 5.2 GHz and 5.9 GHz that is used to filter out the potential interference from some broadband wireless communication systems such as WiMAX and WLAN; besides, two pass-band operating at 4 GHz and 5.5 GHz, which is used for C-band satellite communications systems at the earth station. Although this structure has a multi-band characteristic, it exhibits high stable performance for oblique incidence ranging from 0° to 60° 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° is less than 0.5% on average and very low when compared with existing papers 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.