Analysis and characterization of an octave-bandwidth twin-folded-waveguide slow-wave structure

M Sumathy and Subrata Kumar Datta
Microwave Tube R&D Centre , DRDO, Ministry of Defence, Jalahalli, Bangalore – 560 013, India
Dedicated to Prof B N Basu

A novel configuration of folded-waveguide slow-wave structure was conceptualized in which a pair of identical conventional folded-waveguide slow-wave structures is combined in a contra-twined placement (similar to a contra-wound helix or a ring-bar structure). The proposed structure promises cold-bandwidth close to an octave with lowered interaction impedance. The twin-folded configuration would ease out the manufacturing aspects appreciably and also would allow operation with a larger electron beam carrying higher current or requiring lower focusing magnetic field. The reason being a constituent conventional single folded-waveguide structure operating at a low frequency (having larger dimensions), in its twin-folded configuration, would offer operability approximately at double the frequency over almost an octave bandwidth. The analysis of the structure was carried out by parametric approach and validated against numerical simulation and cold-test measurement, for a structure operating at Ka-band and validated against numerical simulation at W-band. © Anita Publications. All rights reserved.
Keywords: Broadbanding, Folded-waveguide slow-wave structure, Twin-folded-waveguide slow-wave structure.
doi.10.54955/AJP.32.9-12.2023.607-613

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