A simple model for self-consistent calculation of the large-signal behaviour of gyrotrons

The electromagnetic field in a gyrotron resonator is described by a self-consistent method in which the charge due to electrons is represented by a small number of rods of charge. Since the rods are distributed only in angle around the guiding axis, the computer time and storage needed are much less than for simulations in which the equivalent particles are distributed in two dimensions. Calculated results for a gyromonotron oscillator are presented to show the axial variation of the RF B-field and power flow with the static magnetic field, beam current and initial E-field.