Title :
Investigation of an advanced quasi-optical mode converter for a coaxial gyrotron
Author :
Jin, J.B. ; Thumm, M. ; Rzesnicki, T. ; Piosczyk, B. ; Dammertz, G.
Author_Institution :
Assoc. EURATOM-FZK, Inst. fur Hochleistungsimpuls und Mikrowellentechnik, Karlsruhe, Germany
Abstract :
A quasi-optical mode converter is investigated for a 170 GHz, TE34.19 mode coaxial-cavity gyrotron, where the ratio of caustic to cavity radius is 0.323. The dimpled-wall launcher is numerically analysed and optimised to provide a wave beam with scalar Gaussian contents of 94.8% and well-focused field at its aperture. The mirror system is adapted to transform the complicated fields radiated from the launcher into a fundamental Gaussian structure. The tolerance conditions of the mirror system to fabrication errors are also investigated. The achieved conversion efficiency is 97% including amplitude and phase.
Keywords :
gyrotrons; millimetre wave frequency convertors; millimetre wave tubes; 170 GHz; 97 percent; coaxial gyrotron; dimpled-wall launcher; fundamental Gaussian structure; mirror system; quasi-optical mode converter; Apertures; Coaxial components; Fabrication; Gyrotrons; Magnetic confinement; Magnetic resonance; Mirrors; Optical scattering; Optical waveguides; Plasma confinement;
Conference_Titel :
Infrared and Millimeter Waves and 13th International Conference on Terahertz Electronics, 2005. IRMMW-THz 2005. The Joint 30th International Conference on
Print_ISBN :
0-7803-9348-1
DOI :
10.1109/ICIMW.2005.1572527
