Analysis of a Quasi-Optical Launcher Toward a Step-Tunable 2-MW Coaxial-Cavity Gyrotron

Author

Li, Guolin ; Jin, Jianbo ; Rzesnicki, Tomasz ; Kern, Stefan ; Thumm, Manfred

Volume

38

Issue

6

fYear

2010

fDate

6/1/2010 12:00:00 AM

Firstpage

1361

Lastpage

1368

Abstract

A high-efficiency quasi-optical launcher for coaxial-cavity gyrotrons has been investigated with the mode-matching analysis method. The launcher designed for the TE_34,19 mode at 170 GHz is analyzed from 118 to 218 GHz with 67 modes. This investigation is a preliminary study of a launcher toward a step-tunable 2-MW coaxial-cavity gyrotron. Twenty-four modes with fundamental Gaussian mode content (FGMC) that is higher than 90% have been found. At last, nine modes of interest are selected for SURF3D simulations to investigate the transmission properties of millimeter-wave beams through the output window. The results reveal that the beams have deviations of their center points at the RF window within only 2.1 mm, and the FGMCs range from 92.67% to 96.67%. This result indicates that even the present launcher with specific deformations designed for only one mode would be capable of a step-tunable operation.

Keywords

gyrotrons; millimetre wave tubes; mode matching; RF window; SURF3D simulations; TE₁₉ mode; TE₃₄ mode; bandwidth 170 GHz; frequency 118 GHz to 218 GHz; fundamental Gaussian mode content; millimeter wave beams; mode-matching analysis method; power 2 MW; quasi-optical launcher analysis; step-tunable coaxial-cavity gyrotron; Coaxial-cavity gyrotron; frequency step tuning; fundamental Gaussian mode content (FGMC); quasi-optical (q.o.) launcher;

fLanguage

English

Journal_Title

Plasma Science, IEEE Transactions on

Publisher

ieee

ISSN

0093-3813

Type

jour

DOI

10.1109/TPS.2010.2043267

Filename

5439718