Mode Competition Effect on Frequency Locking of a Multimode Gyrotron by a Monochromatic External Signal

We study frequency locking of the gyrotron operating mode by a monochromatic external signal under conditions of competition of several modes. The calculations were performed for a megawatt-power 170-GHz gyrotron with the operating TE28.12 mode. Mode interaction of both equidistant and nonequidistant spectra is considered. Frequency detuning of the modes is comparable to the cyclotron resonance bandwidth. Influence of the external-signal power on the boundaries of the frequency locking zones is studied. The possibility to achieve a high orbital efficiency and broadband frequency tuning in the frequency-locking regime is considered.