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arXiv · 2409.05238

Wideband Glide-Symmetric Double-Corrugated Gap-Waveguide Traveling-Wave Tube for Millimeter Waves

Miguel Saavedra-Melo·Nelson Castro·Robert Marosi·Eva Rajo-Iglesias·Filippo Capolino
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Abstract

We explore the use of glide symmetry (GS) and electromagnetic bandgap (EBG) technology in a glide-symmetric double corrugated gap waveguide (GSDC-GW) slow wave structure (SWS) for traveling wave tube (TWT) applications. Notably, this GS structure provides the advantage of wide-band operation and the EBG eliminates the need for a conductive connection between the top and bottom waveguide plates. The TWT performance is evaluated via particle-in-cell simulations that reveal a 3-dB bandwidth of approximately 12 GHz spanning from 54.5 GHz to 66.3 GHz, accompanied by a maximum gain of 23 dB. Because of GS, the backward wave in the first spatial harmonic is not longitudinally polarized, leading to a low risk of backward wave oscillations in the TWT. This work places the GSDC-EBG structure within the arena of potential SWS topologies for TWTs operating under similar conditions.

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Miguel Saavedra-Melo, Nelson Castro, Robert Marosi, Eva Rajo-Iglesias, Filippo Capolino. 2024-09-08. Wideband Glide-Symmetric Double-Corrugated Gap-Waveguide Traveling-Wave Tube for Millimeter Waves. https://arxiv.org/abs/2409.05238

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