Design of a High-Harmonic Gyrotron With a Permanent Magnet System

This paper presents the conceptual design of a W-band high-harmonic gyrotron oscillator with a permanent magnet system. Mode selection, cavity design, beam-wave interaction calculations, electron-optical system, and quasi-optical mode converter output system are described. The gyrotron operates at the third harmonic of the electron cyclotron frequency with the beam interacting with a TE
₀₂
circular electric mode. The permanent magnet system provided the maximum axial magnetic field of ~ 1.19 T in the cavity region of the gyrotron. In the simulations, an output power of 14 kW has been obtained at a beam voltage of 40 kV with beam current of 3 A, corresponding to an efficiency of 11.7% through optimizing system parameters.