In this article, a series of filtering cavity slot arrays using high-order modes are investigated. It is found that each unit of the cavity slot arrays in the proposed high-order mode resonator is in phase with the same amplitude, which helps enhance the antenna gain and reduce the sidelobe level. Meanwhile, the filtering function is integrated into the design for frequency selectivity and harmonic mode suppression. The higher order response can be achieved by cascading more high-order mode resonators with required external quality factor ( $Q_{e}$ ) and coupling coefficient ( $K$ ). The fractional bandwidth (FBW) and out-of-band suppression of proposed designs are also discussed. For proof-of-concept, a single-band third-order $4\times 5$ filtering cavity slot array using a TM ₄₅₀ mode resonator and a dual-band dual-polarized third-order $4\times 3$ filtering cavity slot array, using TM ₄₃₀ and TM ₃₄₀ mode resonators, are fabricated and tested. The good agreement between the simulated and measured results verifies that the proposed design methodology is feasible for designing high-order mode filtering cavity slot array antennas.

中文翻译：

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双频双偏振滤波腔槽阵列高阶模分析及其应用


在本文中，研究了一系列使用高阶模式的滤波腔槽阵列。结果发现，所提出的高阶模谐振器中腔隙阵列的每个单元同相且幅度相同，这有助于提高天线增益并降低旁瓣电平。同时，设计中还集成了滤波功能，以实现频率选择性和谐波模式抑制。高阶响应可以通过级联更多具有所需外部品质因数 ($Q_{e}$) 和耦合系数 ($K$) 的高阶模式谐振器来实现。还讨论了所提出设计的分数带宽（FBW）和带外抑制。为了进行概念验证，使用 TM ₄₅₀模式谐振器的单频带三阶 $4\times 5$ 滤波腔槽阵列和双频带双极化三阶 $4\times 3$ 滤波腔槽阵列，使用 TM ₄₃₀和 TM ₃₄₀模式谐振器进行制造和测试。仿真结果和测量结果之间的良好一致性证明了所提出的设计方法对于设计高阶模滤波腔隙缝阵列天线是可行的。