This article proposes a novel microstrip directional coupler with high directivity. The proposed coupler was configured using three coupled transmission lines and two reflectors to cancel the leakage components in the isolation ports. To demonstrate the validity of the proposed coupler, we designed and fabricated the microstrip directional coupler with 15 dB coupling at 5.8 GHz. The measurement showed the directivity of 50.0 dB at 5.83 GHz, which was improved by 35.9 dB compared with that of conventional one.

中文翻译：

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高指向性三线微带定向耦合器

本文提出了一种具有高方向性的新型微带定向耦合器。建议的耦合器使用三个耦合传输线和两个反射器进行配置，以消除隔离端口中的泄漏分量。为了证明所提出的耦合器的有效性，我们设计并制造了在 5.8 GHz 下具有 15 dB 耦合的微带定向耦合器。测量结果表明，5.83 GHz 的方向性为 50.0 dB，与传统方法相比提高了 35.9 dB。