Miniaturized dual-band filtering switches are proposed in this article using multimode dielectric resonators (DRs). The planar printed circuit boards (PCBs) are utilized not only to construct the hybrid electromagnetic boundary for quad-mode DR, but also to offer the switchable multimode feeding structures with the p-i-n diodes. When the diodes are reversely biased, all the four modes are excited simultaneously by the mixed electric and magnetic couplings and controlled flexibly to construct the dual-band response. In this manner, extra losses from diodes are avoided, and low-loss transmission is realized. When the diodes are forward biased, all the four modes are shut off at the same time. Owing to the used mixed electric and magnetic couplings, the isolation is enhanced further by the cancellation of the electric and magnetic couplings between the feeding line and the resonant modes. For demonstration, both dual-mode and quad-mode filtering switches with dual-band operations are fabricated and tested. With only one quad-mode DR, high performance, including low-loss dual-band transmission and high-level isolation, is observed in the measurement, making the proposed switches promising in high-standard multiband time division duplex (TDD) systems.

中文翻译：

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使用具有混合边界的多模介质谐振器的双频带滤波开关


本文提出了使用多模介质谐振器 (DR) 的小型化双频带滤波开关。平面印刷电路板 (PCB) 不仅用于构建四模 DR 的混合电磁边界，而且还提供带有 pin 二极管的可切换多模馈电结构。当二极管反向偏置时，所有四种模式都被混合的电和磁耦合同时激发并灵活控制以构造双频带响应。这样就避免了二极管带来的额外损耗，实现了低损耗传输。当二极管正向偏置时，所有四种模式同时关闭。由于使用了混合电和磁耦合，通过消除馈线和谐振模式之间的电和磁耦合进一步增强了隔离。为了进行演示，我们制造并测试了具有双频带操作的双模和四模滤波开关。测量中仅使用一种四模 DR，即可观察到高性能，包括低损耗双频传输和高水平隔离，使得所提出的开关在高标准多频带时分双工 (TDD) 系统中具有广阔的应用前景。