A novel dielectric waveguide filter based on isosceles right‐angled triangular (RAT) resonators is presented in this letter. By connecting the vertices of four isosceles RAT waveguide cavities, a square fourth‐order cross‐coupled waveguide bandpass filter is formed. The presented filter uses the partition wall and shallow blind hole to realize positive coupling and the deep blind hole to realize negative coupling. Moreover, the filter facilitates debugging and testing by setting the debugging blind hole on one side of the waveguide and setting the feed blind hole on the opposite side. The design, analysis, and simulation of the physical model of the filter are discussed. The fabricated filter has a center frequency of 3.5 GHz, relative bandwidth of 5%, insertion loss of less than 1 dB, in‐band return loss of more than 15 dB, and two out‐of‐band transmission zeros at 3.27 and 3.65 GHz.

中文翻译：

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使用等腰直角三角形谐振器的新型介质波导滤波器

本文介绍了一种基于等腰直角三角形（RAT）谐振器的新型介电波导滤波器。通过连接四个等腰RAT波导腔的顶点，形成一个方形的四阶交叉耦合波导带通滤波器。提出的滤波器利用隔墙和浅盲孔实现正耦合，深盲孔实现负耦合。此外，该滤波器通过将调试盲孔设置在波导的一侧并将馈送盲孔设置在相对的一侧来简化调试和测试。讨论了滤波器物理模型的设计，分析和仿真。人造滤波器的中心频率为3.5 GHz，相对带宽为5％，插入损耗小于1 dB，带内回波损耗大于15 dB，