Asian Journal of Physics Vol 32, Nos 9 – 12 (2023) 593-599

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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  1. Sengele S, Jiang H, Booske J H, Kory C L, Weide D W, Ives R L, Microfabrication and characterization of a selectively metallized W-band meander-line TWT circuit, IEEE Trans Electron Devices, 56(2009)730–737.
  2. Shen F, Wei Y, Yin H, Gong Y, Xu X, Wang S, Wang W, Feng J, A Novel V-shaped microstrip meander-line slow-wave structure for W-band MMPM, IEEE Trans Plasma Sci, 40(2012)463–469.
  3. Shen F, Wei Y, Xu X, Liu Y, Huang M, Tang T, Gong Y, U-shaped microstrip meander-line slow-wave structure for Ka-band traveling-wave tube, International Conference on Microwave and Millimeter Wave Technology (ICMMT), 2012.
  4. Shen F, Wei Y, Xu X, Liu Y, Huang M, Tang T, Duan Z, and Gong Y, Symmetric double V-shaped microstrip meander-line slow-wave structure for W-band traveling-wave tube, IEEE Trans Electron Devices, 59(2012)1551–1557.
  5. Paschke F, A Note on the dispersion of interdigital delay lines, RCA Rev, 9(1958)418–422.
  6. Yamada I, Takagi T, A new type of traveling-wave deflection system, IEEE Trans Electron Devices, 19(1972)204–213.
  7. Weiss J A, Dispersion and field analysis of a microstrip meander-line slow-wave structure, IEEE Trans. Microw Theory Tech, 22(1974)1194–1201.
  8. Silin R A, Periodicheskie Volnovody, Moscow: FAZIS, 2002 (Silin R A, Periodic Waveguides, Moscow: Phasis), 2002.
  9. Sumathy M, Christie L, Datta S K, Kumar L, Analysis of a W-band meander-line slow-wave structure for millimeter-wave traveling-wave tubes, IEEE International Vacuum Electronics Conference, 2012.
  10. Sumathy M, Augustin D, Datta S K, Christie L, Kumar L, Design and RF characterization of meander-line and folded-waveguide slow-wave structures for traveling-wave tubes, IEEE Trans Electron Devices,   60(2013)1769–1775.
  11. Bhat B, Koul S K, Stripline-like Transmission Lines for Microwave Integrated Circuits, (Wiley Eastern Limited, New Delhi, India), 1987.
  12. Computer Simulation Technology (CST) GmbH. Online: