High efficient quasi-optical mode converter for coaxial ITER gyrotron

Author

Jin, Jianbo ; Thumm, Manfred ; Piosczyk, Bernhard ; Kern, Stefan ; Flamm, Jens ; Rzesnicki, Tomasz

Author_Institution

Inst. fur Hochleistungsimpuls-und Mikrowellentech. (IHM), Forschungszentrum Karlsruhe, Karlsruhe, Germany

fYear

2009

fDate

28-30 April 2009

Firstpage

279

Lastpage

280

Abstract

A 2 MW, 170 GHz, TE_34,19 mode coaxial-cavity gyrotron is under development for ITER at Forschungszentrum Karlsruhe (FZK), Germany. A prototype of the quasi-optical (q.o.) mode converter has been designed and tested for this gyrotron to transform the cavity mode into a fundamental Gaussian distribution. High power measurements show that the fundamental Gaussian mode content of the RF wave beam is about 85% at the output window. A new method has been used to improve the performance of the q.o. mode converter. The simulation results reveal that the fundamental Gaussian mode content can be enhanced to 97.7% at the output window plane.

Keywords

gyrotrons; waveguide antennas; Gaussian mode; RF wave beam; coaxial ITER gyrotron; fundamental Gaussian distribution; quasi-optical mode converter; Apertures; Coaxial components; Diffraction; Gaussian distribution; Gyrotrons; Mirrors; Power measurement; Prototypes; Radio frequency; Surface waves; Gyrotrons; cylindrical waveguides; mode conversion; waveguide antennas;

fLanguage

English

Publisher

ieee

Conference_Titel

Vacuum Electronics Conference, 2009. IVEC '09. IEEE International

Conference_Location

Rome

Print_ISBN

978-1-4244-3500-5

Electronic_ISBN

978-1-4244-3501-2

Type

conf

DOI

10.1109/IVELEC.2009.5193400

Filename

5193400