This letter proposes a direct matrix synthesis approach for filters with cascaded extracted-pole (EP) sections. The novel synthesis technique is based on the observation that an EP section is a special case of a singlet with a zero mainline coupling. With proper phase lengths inserted into a cross-coupled network, cascaded EP sections can be directly synthesized from the canonical wheel form by a sequence of elementary matrix operations. In this letter, the equation for the suitable phaselength is derived, and the matrix transformation strategy to synthesize cascaded EP sections is developed. Numerical synthesis examples are provided to validate the novel synthesis approach.

中文翻译：

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具有级联提取极点部分的滤波器的矩阵综合


这封信提出了一种用于具有级联提取极点（EP）部分的滤波器的直接矩阵合成方法。这种新颖的合成技术基于以下观察：EP 部分是具有零主线耦合的单线态的特殊情况。通过将适当的相位长度插入交叉耦合网络，可以通过一系列初等矩阵运算从规范轮形式直接合成级联 EP 部分。在这封信中，推导了合适相长的方程，并开发了合成级联 EP 部分的矩阵变换策略。提供了数值综合示例来验证新颖的综合方法。