Wideband Frequency Selective Surface Based on Quarter-Mode Substrate Integrated Waveguide

A wideband frequency selective surface (FSS) based on a quarter-mode substrate integrated waveguide (QMSIW) is proposed and designed in this paper. Firstly, a QMSIW cavity is designed to achieve a passband. Then, in order to expand the bandwidth, a passband with two additional transmission poles are achieved by using aperture-coupled resonator (ACR) structure. Hence, three transmission poles are generated. The working principles of transmission poles are analyzed by means of odd-even mode analysis and cavity mode analysis. Furthermore, a sharp roll-off is created at one side of the passband, due to the transmission zero generated by the QMSIW cavity. In general, a wideband FSS is proposed with the passband about 33%.