In this letter, the modified flat-roofed sine waveguide slow-wave structure (FRSWG-SWS) is proposed for the wideband high-power sub-terahertz traveling-wave tube (sub-THz TWT), which possesses the advantages of wide operating bandwidth, low loss, minimal reflection, and ease of fabrication. The simulation results demonstrate that the transmission parameter is more than −5.0 dB in the frequency range between 210 and 250 GHz. The beam–wave interaction results indicate that the modified FRSWG can provide over 50 W of output power and 30 dB of gain from 205 to 250 GHz with sheet electron beam with a voltage of 20.8 kV and a current of 150 mA. Finally, we use high-speed milling to fabricate the modified FRSWG by the nano-Computer Numerical Control (CNC) technology. The cold test results demonstrate that the modified FRSWG has low loss and good reflection characteristics.

中文翻译：

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用于宽带 220-GHz TWT 的改进平顶正弦波导慢波结构的研究

本文针对宽带大功率亚太赫兹行波管（sub-THz TWT）提出了改进的平顶正弦波导慢波结构（FRSWG-SWS），具有宽工作带宽的优点、低损耗、最小反射和易于制造。仿真结果表明，传输参数在 210 和 250 GHz 之间的频率范围内大于 −5.0 dB。束波相互作用结果表明，改进后的 FRSWG 可以在 205 至 250 GHz 的范围内提供超过 50 W 的输出功率和 30 dB 的增益，片状电子束的电压为 20.8 kV，电流为 150 mA。最后，我们使用高速铣削通过纳米计算机数控 (CNC) 技术制造改进的 FRSWG。