A low voltage standing wave ratio (VSWR) broad bandwidth pillbox window with metamaterial is proposed for W-band traveling-wave tubes (TWTs) in this paper. The metamaterial structure is designed on a dielectric surface, which decreases the VSWR and broadens the bandwidth of the pillbox window. The cold-test results of the window with metamaterial are presented, which showed that the metamaterial pillbox window (MPW) achieves a bandwidth of 31.5 GHz with VSWR below 1.2, and a bandwidth of 18 GHz with VSWR below 1.1. The ghost mode and the power capacity of the window were also investigated. The results showed that the proposed metamaterial pillbox window is suitable for medium power TWTs. A Ka-band MPW was fabricated and the test results agreed well with the simulation results.

中文翻译：

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用于 W 波段行波管的宽带宽超材料药盒窗


本文提出了一种用于 W 波段行波管 (TWT) 的低电压驻波比 (VSWR) 宽带宽药盒窗超材料。超材料结构设计在介电表面上，降低了驻波比并拓宽了药盒窗口的带宽。给出了超材料窗口的冷测试结果，结果表明超材料药盒窗口（MPW）实现了 31.5 GHz 的带宽和 VSWR 低于 1.2 的带宽，以及 18 GHz 的带宽和 VSWR 低于 1.1 的带宽。还研究了幻影模式和窗口的功率容量。结果表明，所提出的超材料药盒窗适用于中等功率行波管。制作了Ka波段MPW，测试结果与仿真结果吻合良好。