Time-Dependent Nonlinear Theory and Numerical Simulation of 94 GHz Complex Cavity Gyrotron

A time-dependent nonlinear theory for complex cavity gyrotron is presented in this paper. The theory includes generalized telegrapher's equations and electron motion equations, which are deduced in detail. A calculation code for the self-consistent nonlinear beam-wave interaction is developed based on the presented theory. Using the code, a 94GHz complex cavity gyrotron operating in TE021{ TE031 modes is thoroughly studied. Numerical results show that an output power of 180kW, about 36% e-ciency is achieved with a 50kV, 10A electron beam at a focused magnetic fleld of 1.78T and a beam velocity ratio of 1.65. The results from MAGIC simulation are also given and an output power of 192kW, 38.4% e-ciency is obtained This tells the agreement with these two simulation codes.