ABSTRACT A microstrip diplexer with upper-stopband and high isolation is presented in this paper. A multimode resonator is designed by using stub-loaded circuit, which can be employed as the common resonator to replace the common matching network of the diplexer. The resonant frequency of the multimode resonators can be adjusted flexibly by changing the length of the open stub and shorted stub, respectively. The proposed diplexer working at center frequencies of 1.8 and 3.5 GHz with over 45 dB isolation is finally simulated, fabricated, and measured. The measured results are in good agreement with the simulated ones.

中文翻译：

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具有宽上阻带和高隔离度的紧凑型多模谐振器双工器

摘要 本文提出了一种具有高阻带和高隔离度的微带双工器。采用短截线加载电路设计了一种多模谐振器，可作为公共谐振器代替双工器的公共匹配网络。多模谐振器的谐振频率可以通过分别改变开路短截线和短接短截线的长度来灵活调整。建议的双工器工作在 1.8 和 3.5 GHz 的中心频率，隔离度超过 45 dB，最终被模拟、制造和测量。实测结果与模拟结果吻合较好。