A Dual-band Reconfigurable Frequency Selective Surface with Independent Tuning Capability

In this letter, a dual-polarization miniaturized dual-band reconfigurable frequency selective surface (RFSS) is proposed Initially, the principle of the proposed design method and design procedure are presented based on the equivalent circuit model (ECM). Based on this, we design a dual-passband RFSS consisting of two bandpass FSSs in a back-to-back configuration with an embedded curved spiral cross grid in the middle layer, where the varactors symmetrically soldered on the gaps of the top and bottom layers. By changing the bias voltages of the varactors, the independent tunability of the dual passbands is realized. The proposed RFSS can provide a wide tunable range above 1.30 GHz for two passbands. Moreover, the miniaturized feature enables the structure process a lower profile and better angular stability. Finally, a sample is fabricated and measured, whose results and simulated results have a good agreement. The proposed structure has potential application in the FSS radome multiband and multifunctional communication systems.