High power microwave sources and their requirements

Each microwave source has its own optimum pulse power supply. Specific applications usually dictate power supply features such as pulse repetition frequency, pulse duration, total integrated number of pulses and total system dimensions. The microwave generator, as a load element, itself requires of the pulsed power supply certain electrical characteristics. These requirements usually determine the voltage, the impedance and the allowable variation in the voltage both from pulse to pulse and within a single pulse. This has been illustrated by an experimental comparison of the gyrotron and the cyclotron autoresonance maser (CARM) pulse power supply requirements. It has been shown that for these two devices there are major differences in the requirements. In a series of experiments in which both types of device have been successfully operated, the gyrotron has been shown to be relatively robust to voltage variations and does not necessarily require a voltage above 100 kV, whereas the CARM has required a higher voltage pulse, typically 1300 kV and a pulse with <5% voltage variation over a period of ~100 ns