In this article, a compact tri‐band high‐temperature superconducting filter with controllable coupling and feeding structures based on crossed resonator which consists of two‐end‐open UIR with a short stub and an open stub shunted at the resonator center is proposed. Due to the symmetrical structure of the proposed resonator, the odd‐ and even‐mode analysis method can be used to derive their resonance frequencies. Then, a capacitance‐loaded microstrip line is added between the resonators to flexibly control the bandwidths. Furthermore, one tapped line and one coupled line are utilized to realize the acquired external coupling under prior specifications. For demonstration, a tri‐band filter operating at 1.6 GHz (Global Positioning System), 2.45 GHz (Wireless Local Area Networks), and 3.5 GHz (WiMAX) is designed, analyzed using the electromagnetic simulator, and fabricated using an YBa₂Cu₃O_y thin film on an MgO substrate. The measured results agree well with the simulated ones.

中文翻译：

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基于交叉谐振器的三频超导滤波器，具有可控的耦合和馈电结构

本文提出了一种紧凑的三频高温超导滤波器，该滤波器具有基于交叉谐振器的可控耦合和馈电结构，该滤波器由两端开有短短截线的UIR和在谐振器中心分流的开放短截线组成。由于所提出的谐振器的对称结构，奇数和偶数模式分析方法可用于推导其谐振频率。然后，在谐振器之间增加了一条电容加载的微带线，以灵活地控制带宽。此外，在先有技术条件下，利用一根抽头线和一根耦合线来实现所获取的外部耦合。为了演示，设计了工作在1.6 GHz（全球定位系统），2.45 GHz（无线局域网）和3.5 GHz（WiMAX）的三频带滤波器，MgO衬底上的₂ Cu ₃ O _y薄膜。测量结果与模拟结果吻合良好。