Quasi-TEM analysis of coupled meander-line slow-wave structures for millimeter-wave traveling-wave tubes

Murugan 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

Quasi-TEM analysis of a symmetrically coupled meander-line slow-wave structure was developed for the analysis of the dispersion and interaction impedance characteristics of the structure. The circuit comprises a pair of identical conventional meander-line slow-wave structures that are closely placed in overlapping position. The coupled slow-wave structure supports even and odd hybrid modes, and promises enhanced on-axis interaction impedance for the odd hybrid mode. The analytically obtained dispersion and interaction impedance characteristics were benchmarked against those from 3-D electromagnetic analysis using CST Microwave Studio for two structures operating at Ka- and Q-bands. The Ka-band structure was fabricated and cold test measurement was carried out for the dispersion characteristics and compared against those from quasi-TEM and 3D electromagnetic analyses. © Anita Publications. All rights reserved.
Keywords: Coupled meander-line; Quasi-TEM analysis; Slow-wave structure (SWS); Traveling-wave tubes.

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