Tunable frequency selective surface based on IDC-loaded electric-LC resonator incorporated with liquid crystal

Characterization of a tunable electric-LC resonator is presented in this work. The tuning is obtained through using liquid crystal material in the central capacitor gap. Fitting the resonator with an interdigital capacitor, increases the total capacitance of the structure as well as the tuning range. An equivalent circuit model synthesis is proposed to simplify the design procedure of the FSS. The result of the full-wave electromagnetic simulation along with the result of circuit simulation indicate a tuning range of 7.73%, between 4.60 to 4.97 GHz. The final resonator designed in this work can be used in an array to form a tunable frequency selective surface.