A broadband rectangular waveguide TE 10 –TE 20 mode converter with high mode purity and conversion efficiency is designed, fabricated and measured in this Letter. Based on the broadband characteristic of ridged twist waveguide and its characteristic of polarisation direction torsion of electromagnetic wave, this mode converter achieves broadband and high-efficiency TE 10 –TE 20 mode conversion. Simulation results reveal that the return loss of the proposed mode converter is >20 dB and insertion loss is <0.04 dB in whole Ka-band. Two prototype TE 20 mode converters were fabricated. Back-to-back millimeter-wave measurements by vector network analyser were performed to verify the design. The measured performances show return loss of the proposed mode converter is >20 dB and insertion loss is 97.7%.

中文翻译：

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一种宽带矩形波导TE10-TE20模式转换器的设计与测试

本文设计、制造和测量了一种具有高模式纯度和转换效率的宽带矩形波导 TE 10 –TE 20 模式转换器。该模式转换器基于脊形扭曲波导的宽带特性及其电磁波偏振方向扭转的特性，实现了宽带、高效的TE 10 -TE 20 模式转换。仿真结果表明，所提出的模式转换器的回波损耗 >20 dB，整个 Ka 波段的插入损耗 <0.04 dB。制造了两个原型 TE 20 模式转换器。使用矢量网络分析仪进行背靠背毫米波测量以验证设计。测得的性能表明，所提出的模式转换器的回波损耗 >20 dB，插入损耗为 97.7%。