Third-harmonic complex cavity gyrotron self-consistent nonlinear analysis

Starting from general transmission line equations with an electron beam source, a self-consistent nonlinear theoretical model for a complex cavity gyrotron with gradual transitions is presented in this paper. The model accounts for mode coupling in the transition region of the complex cavity. The interaction between the electron beam and H/sub 61/-H/sub 62/ RF field in the complex cavity for a third-harmonic gyrotron is simulated; many calculations are carried out under different cavity dimensions and electron beam parameters.