On the Method of Generation of the Periodic Sequence of Ultrashort Gigawatt Pulses with the Nanosecond Repetition Period in the Superradiance Mode of the Relativistic Backward Wave Oscillator

A method of generating a periodic sequence of powerful ultrashort microwave pulses based on the superradiant mode of a relativistic backward wave oscillator during one pulse of the current of the high-current relativistic electron beam of nanosecond duration is proposed and implemented. Based on non-stationary numerical codes, it is demonstrated that this mode is implemented by introducing reflections at the ends of the system of decelerating generators. The effectiveness of the method has been confirmed experimentally for generation frequencies of 10 GHz and 12 GHz. The modes of generation of ultrashort (duration about 1 ns) gigawatt microwave pulses with a repetition period in units of nanoseconds (repetition frequency of hundreds of megahertz) are obtained. The conversion coefficients of such pulses, defined as the ratio of the peak power of microwave radiation to the power of the electron beam, reached values above one. In the experiment, a correlation has been observed between the sequence of pulses and their strict periodicity.