Numerical Simulation of the Efficiency of 50 GHz Gyrotron Microwave Tube

Abstract

This paper presents a simulation study to evaluate the efficiency of a 50 GHz microwave tube operating in the TE₄₁₁ (high- order mode) using computer programming techniques. A simulation program was developed using FORTRAN language to design a single open- cavity gyrotron and investigate the interaction between the electron beam and electromagnetic waves inside the cavity. The program calculates key parameters such as the initial electron guiding center position and the Lamar radius.

The input parameters include the energy of electron, the ratio of velocity, normalized length of cavity, normalized external magnetic field strength and the mode indices (m, n, l), as well as the zero root of the Bessel function J'_m=0. the study models an open cavity structure, with an annular mono energetic electron beam exhibiting constant oscillation amplitude. The electron beam is injected into the cavity and propagates under the influence of an external magnetic field.