Frequency selective surface with wide range of tunability

Recent communication systems demand multifunctional frequency selective surfaces (FSSs) which have more than one frequency response. As a solution proposal, a novel band stop periodic element geometry which can be tuned between 1.8 GHz-5.8 GHz frequency bands is presented in this work. Trapezoid loop geometry is used as an FSS geometry in order to achieve wide tuning range. Tuning feature is achieved by inclusion of varactor diodes between trapezoid loop geometries. Proposed structure allows independent tuning for vertical and horizontal polarizations. Analyzes of the proposed surfaces are executed with Ansoft HFSS v.15 software.