Folded-waveguide slow-wave structure for G-band traveling wave tube amplifier

Surya Prasath C and Richards Joe Stanislaus
School of Electronics Engineering, Vellore Institute of Technology Chennai, Vandalur Kelambakkam Road, Chennai- 600 127, India
This paper is dedicated to Dr Shrinivas Joshi

A folded waveguide slow wave structure for high power, wideband, and high efficiency G-band traveling wave tube amplifier is presented in this article. Through eigenmode analysis in commercial software, the phase velocity of the proposed SWS was analytically achieved with 0.235 times the velocity of light. The interaction impedance of the proposed SWS was computed using an in-house developed MATLAB application. A cylindrical electron beam with beam current 35 mA and voltage 14.54 kV, was utilized in the beam-wave interactions, with a beam fill factor of 65 % within the beam tunnel. An RF output power of over 11 dBW with a minimum gain of 23 dB was successfully attained across the operational bandwidth of 28 GHz. The electron beam was focussed with a focusing magnetic field of 0.38 T and the Particle-in-cell simulations were performed using CST Particle Studio. Peak power of 14.25 dBW was effectively achieved, with a maximum gain of 26.3 dB at 224 GHz. The designed SWS proves to be a highly suitable candidate for the G-band traveling wave tube amplifiers for the use in radio astronomy and point-to-point 6G backhaul communications. © Anita Publications. All rights reserved.
Doi: 10.54955/AJP.33.9-10.2024.641-649
Keywords: Vacuum electronic amplifier, Millimetre wave, High power amplifiers, Folded waveguide, G-band broadband Amplifiers.

Peer Review Information
Method: Single- anonymous; Screened for Plagiarism? Yes
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