In this letter, a full-band balanced frequency doubler covering 140–220 GHz range is reported. To feed the Schottky barrier diodes (SBDs) with a reverse phase, a novel inline waveguide-to-microstrip (WG-to-MS) transition is adopted, which is used as mode conversion and broadband balun simultaneously. The generated second-harmonic is extracted directly by a taper waveguide, which also serves as broadband output matching. Compared with traditional Erickson-style frequency doublers, the presented doubler not only possesses an inherent inline input–output configuration, but also eliminates the dielectric loss and transition loss at the output circuit with an expanded bandwidth. To verify the proposed concept, the doubler is fabricated and measured, which exhibits a conversion efficiency of 6.8%–11.6% across the whole 140–220 GHz band under 10–20 mW input power.

中文翻译：

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覆盖140～220GHz、效率6.8%～11.6%的平衡倍频器


在这封信中，报告了覆盖 140-220 GHz 范围的全频段平衡倍频器。为了向肖特基势垒二极管 (SBD) 提供反相馈电，采用了新型内联波导到微带 (WG-to-MS) 转换，该转换同时用作模式转换和宽带巴伦。产生的二次谐波由锥形波导直接提取，该波导也用作宽带输出匹配。与传统的Erickson型倍频器相比，所提出的倍频器不仅具有固有的串联输入输出配置，而且消除了输出电路处的介电损耗和过渡损耗，并具有扩展的带宽。为了验证所提出的概念，我们制作并测量了倍频器，该倍频器在 10-20 mW 输入功率下在整个 140-220 GHz 频段上表现出 6.8%-11.6% 的转换效率。