Mechanisms of Intense Pulses Generation in Gyrodevices

We study theoretically and experimentally two mechanisms of generation of intense pulses trains under cyclotron resonance interaction of electromagnetic radiation with electron beams. The first mechanism is based on transformation of CW radiation into a train of SIT -solitons when an electron beam is initially rectilinear (absorbing). The second mechanism realizes in a gyrotron, operating with high excess of an electron current over the starting conditions. Results of corresponding Ka-band experiments are presented. Both mechanisms are of interest as methods of frequency-comb generation in microwave electronics.