Modeling of mode purity in high power gyrotrons

Journal Article · Thu Apr 01 04:00:00 EST 1993 · Bulletin of the American Physical Society

DOI:https://doi.org/10.1109/PLASMA.1993.593497· OSTI ID:243590

Cai, S Y; Antonsen, Jr, T M; Saraph, G P ^[1]

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1. Univ. of Maryland, College Park, MD (United States); and others

Spurious mode generation at the same frequency of the operational mode in a high power gyrotron can significantly reduce the power handling capability and the stability of a gyrotron oscillator because these modes are usually not matched at the output window and thus have high absorption and reflection rates. To study the generation of this kind of mode, the authors developed a numerical model based on an existing multimode self-consistent time-dependent computer code. This model includes both TE and TM modes and accounts for mode transformations due to the waveguide inhomogeneity. With this new tool, they study the mode transformation in the gyrotron and the possibility of excitation of parasitic TE and TM modes in the up taper section due to the gyroklystron mechanism. Their preliminary results show moderate excitation of both TE and TM modes at the same frequency as the main operating mode at locations near their cutoff. Details of the model and further simulation results will be presented.

• Sponsoring Organization: USDOE
• OSTI ID: 243590
• Report Number(s): CONF-9304297--
• Journal Information: Bulletin of the American Physical Society, Journal Name: Bulletin of the American Physical Society Journal Issue: 2 Vol. 38; ISSN BAPSA6; ISSN 0003-0503
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
43 PARTICLE ACCELERATORS
MATHEMATICAL MODELS
MICROWAVE AMPLIFIERS
MODE CONTROL
STABILITY