Investigation of a Broadband Quasi-Optical Mode Converter for a Multi-Frequency 1 MW Gyrotron

被引：0

作者：

X. Yang

A. Arnold

E. Borie

G. Dammertz

O. Drumm

K. Koppenburg

B. Piosczyk

D. Wagner

M. Thumm

机构：

[1] Forschungszentrum Karlsruhe,

[2] Association EURATOM-FZK,undefined

[3] Institut fuer Hochleistungsimpuls- und Mikrowellentechnik,undefined

[4] D-,undefined

[5] Universitaet Karlsruhe,undefined

[6] Institut fuer Hoechstfrequenztechnik und Elektronik,undefined

[7] Max-Planck-Institut fuer Plasmaphysik,undefined

[8] Association EURATOM-IPP,undefined

[9] Boltzmannstr.2 D-,undefined

来源：

International Journal of Infrared and Millimeter Waves | 2004年 / 25卷

关键词：

frequency step-tunable gyrotron; Gaussian beam; QO mode converter; wall perturbation;

D O I：

暂无

中图分类号：

学科分类号：

摘要：

A broadband quasi-optical (QO) mode converter for a multi-frequency gyrotron has been designed and tested at Forschungszentrum Karlsruhe (FZK). The launcher is optimized for the TE22,8 mode at 140 GHz, but the radiated beams present an almost identically focused pattern for all 9 considered modes between 105 GHz (TE17,6) and 143 GHz (TE23,8). Combining with a beam-forming mirror system, which consists of a quasi-elliptical mirror and two phase-correcting mirrors with non-quadratic surface contour, further calculations show that efficiencies of more than 94% have been achieved for converting the rotating high-order cylindrical cavity modes into the usable fundamental Gaussian mode. Low power (cold) measurements show a good agreement with theoretical predictions. This QO mode converter can be used for the broadband operation of a multi-frequency 1 MW gyrotron.

引用

页码：1557 / 1566

页数：9