Angularly and Switching—stable AFSS based on coupling principle

An active bandpass frequency selective surface (AFSS) is proposed in this paper based on the coupling principle, with good angularly and switching stabilities. Taking the wrench -shaped patch as the basic unit, AFSS tuning function is realized by changing the traditional structure and arrangement of wrench -shaped patch. Parameter analysis and equivalent circuit model are illustrated to explain the resonance behavior of the proposed AFSS. Numerical analysis software CST showed that by rotating the upper patch at 0°-120°, AFSS can be tuned in 6.36GHz -- 8.81GHz. It is demonstrated that the insertion loss can be reduced by changing the arm width of the unit, and the insertion loss can be kept within a certain range during tuning. According to the simulation and calculation, the FSS structure maintains good angularly stability within 0°-80° and has good switching stability during frequency band switching.