Theoretical investigation of parasitic oscillation at operating-mode harmonics in gyrotrons

The paper develops a theory of the excitation of forced parasitic oscillations at operating-mode harmonics in gyrotrons operating at fundamental cyclotron resonance. An analysis is made of the dependence of the longitudinal structure and power of the parasitic oscillations on the amplitude of the operating mode and the detuning of the natural frequencies of the operating and parasitic modes. The theory developed makes it possible to interpet the experimental results of Danly et al. (1985).