A dual band reconfigurable active frequency selective surface is designed which resonates at 2.5 and 3.6 GHz as transmission pole frequencies. Lower and upper pass bands have −3 dB bandwidths of 0.4 and 0.5 GHz, respectively. Two notch frequencies are configured from 4.71 to 3.5 GHz and from 2.78 to 2.45 GHz. Dimensions of the unit cell are optimized to λ 0/10 calculated at the lowest resonance. The proposed design exhibits insignificant variation at oblique excitation angles until 75° of dual polarized plane wave. An equivalent circuit model is developed for optimization and vivid understanding of the structure behaviour. A prototype of the designed structure is fabricated and the measured response is in satisfactory agreement with the simulated transmission response. High angle stability, low insertion loss at both the transmission pole frequencies, dual band pass/stop tuning for single and dual polarized wave with use of only two varactor diodes are eminent features of the design.

中文翻译：

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一种高角度稳定和极化对称的双频带可重构频率选择表面

设计了一种双频带可重构有源频率选择表面，该表面在 2.5 和 3.6 GHz 作为传输极点频率处产生共振。下通带和上通带分别具有 0.4 和 0.5 GHz 的 -3 dB 带宽。两个陷波频率配置为 4.71 至 3.5 GHz 和 2.78 至 2.45 GHz。单元格的尺寸被优化为λ 0/10 以最低共振计算。所提出的设计在双极化平面波的 75° 之前在倾斜激发角处表现出微不足道的变化。开发了一个等效电路模型，以优化和生动地理解结构行为。制作了设计结构的原型，测量的响应与模拟的传输响应非常吻合。高角度稳定性、两个传输极点频率下的低插入损耗、仅使用两个变容二极管的单极化波和双极化波的双带通/停止调谐是该设计的显着特点。