This letter presents a novel, simpler, and more accurate synthesis method for inline extracted-pole low-pass prototype filters. At the present, this topology is only synthesized by using section extraction or optimization methods, known to suffer from accuracy problems, especially for high-order filters. The method described in this letter relies on the robustness and accuracy of the coupling-matrix synthesis methods by using it as a first step. The second step is instead a transformation to obtain the desired inline extracted-pole topology. Three synthesis examples are presented to validate the novel synthesis procedure.

中文翻译：

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通过拓扑变换精确合成提取极点滤波器

这封信提出了一种用于在线提取极点低通原型滤波器的新颖、更简单且更准确的合成方法。目前，这种拓扑仅通过使用截面提取或优化方法进行合成，已知存在精度问题，尤其是对于高阶滤波器。这封信中描述的方法依赖于耦合矩阵合成方法的稳健性和准确性，将其用作第一步。第二步是进行转换以获得所需的内联提取极点拓扑。提供了三个合成示例来验证新的合成程序。