Highly Efficient Gyrotron Mode Converter With a Launcher Changing Angular Spectrum of the Operating Mode

• Published in: IEEE transactions on electron devices Vol. 71; no. 12; pp. 7831 - 7835
• Main Authors: Gashturi, A. P., Sobolev, D. I., Denisov, G. G., Proyavin, M. D., Morozkin, M. V., Chirkov, A. V.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.12.2024; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Algorithms; Cyclotron resonance devices; Diffraction; Electromagnetic waveguides; Gaussian beams (optics); Gyrotron; Gyrotrons; high-power radiation; Indexes; Launchers; millimeter waves; Mirrors; Multipoles; Optical waveguides; Propagation modes; Reflection; Scattering; Shape; Surface waves; Wave diffraction; Wave propagation; Waveguides
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/TED.2024.3479157

To minimize diffraction losses and the dimensions of the quasi-optical converter, a unique waveguide launcher is proposed to be used in the output system of a 28-GHz gyrotron operating on the TE<inline-formula> <tex-math notation="LaTeX">_{-{1.2}} </tex-math></inline-formula> mode with a small Brillouin angle at its input. The launcher converts the gyrotron operating mode into a Gaussian-like wave beam with an efficiency of more than 98%, propagating with a big Brillouin angle to the axis of the launcher. The launcher is designed using a hybrid synthesis/method of moment (MoM) + multilevel fast multipole algorithm (MLFMA) approach, and two versions of the waveguide launcher are manufactured using two different technologies. The experiment confirmed the high efficiency of the quasi-optical converter.