ABSTRACT Based on the multi-coupled line, a novel compact microstrip diplexer with high isolation and low insertion loss is developed. The presented diplexer consists of five short-ended parallel coupled lines to implement the desired channel selections while exempting the use of extra T-junction matching networks, as compared with the conventional case. The design concept is detailed and a prototype diplexer is developed and examined experimentally, where the two channels are of center frequencies of 1.8 and 2.4 GHz, respectively. On the other hand, a figure-of-merit (FOM) is, for the first time, presented to evaluate the comprehensive performance of a diplexer. Results indicate the demonstrator diplexer has a size of 0.18 λg×0.34 λg and a very high FOM of 19301. Measurements match well with the simulations.

中文翻译：

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基于多耦合线的高品质因数微带双工器

摘要 基于多耦合线，研制了一种新型的高隔离度、低插入损耗的紧凑型微带双工器。与传统情况相比，所提出的双工器由五个短端平行耦合线组成，以实现所需的通道选择，同时免除使用额外的 T 结匹配网络。详细设计概念并开发了原型双工器并进行了实验检查，其中两个通道的中心频率分别为 1.8 GHz 和 2.4 GHz。另一方面，首次提出品质因数 (FOM) 来评估双工器的综合性能。结果表明，演示器双工器的尺寸为 0.18 λg×0.34 λg，FOM 非常高，为 19301。测量结果与模拟结果非常吻合。