By introducing an open stub loaded resonator (OSLR) and a uniform impedance resonator (UIR) into balanced stepped-impedance microstrip-slotline transition structures, a balanced dual-band bandpass filter (BPF) with high selectivity and low insertion loss performance is presented in this paper. The balanced microstrip-slotline transition structures can achieve a wideband common-mode (CM) suppression. Meanwhile, the differential-mode (DM) passbands are independent from the CM responses, which greatly simplifies the design procedure. In addition, four varactors are loaded into OSLR and UIR to achieve the electrical reconfiguration. The proposed balanced dual-band BPF can realize quasi-independently tunable center frequencies and bandwidths. In order to verify the feasibility of the proposed design method, a prototype circuit of the proposed reconfigurable balanced dual-band BPF is simulated, fabricated and measured. A good agreement between the simulation and measurement results is observed.

中文翻译：

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具有准独立可调中心频率和带宽的平衡双频 BPF

通过在平衡阶梯阻抗微带-槽线过渡结构中引入开放短截线负载谐振器（OSLR）和均匀阻抗谐振器（UIR），提出了一种具有高选择性和低插入损耗性能的平衡双频带带通滤波器（BPF）。这张纸。平衡的微带-槽线过渡结构可以实现宽带共模（CM）抑制。同时，差模 (DM) 通带独立于 CM 响应，大大简化了设计过程。此外，将四个变容二极管加载到 OSLR 和 UIR 中以实现电气重构。所提出的平衡双频BPF可以实现准独立可调的中心频率和带宽。为了验证所提出的设计方法的可行性，对所提出的可重构平衡双频 BPF 的原型电路进行了仿真、制造和测量。观察到模拟和测量结果之间的良好一致性。