Formation of Microwave Soliton Trains Due to Modulation Instability under Cyclotron Resonance Interaction of an Initially Rectilinear Electron Beam with a Backward Electromagnetic Wave

It is known that under the resonant interaction of a moving beam of unexcited electron cyclotron oscillators with a backward electromagnetic wave, conversion of a continuous-wave (CW) signal into a sequence of short soliton-like pulses may occur. In this paper, this phenomenon is explained based on the theoretical study of the modulation instability (MI). The analysis shows the possibility of implementing several dynamic regimes depending on the amplitude and frequency of the input harmonic signal. Analytical expressions for the threshold values of the driving power and frequency required for the soliton generation are derived and compared with the results of numerical simulation. The results of the experimental study of soliton formation are also discussed.