The split-cavity oscillator: a high-power E-beam modulator and microwave source

A compact device, called a split-cavity oscillator, whose self-excited oscillating electromagnetic field converts a large-area steady electron beam into one that is highly density modulated, is described. It does this in a short beam travel length, easing both space-charge and pinching limitations. Thus, high currents are possible without requiring a magnetic guide field. Methods for converting the modulated output beam into high-power microwaves are discussed, as are ways to phase-lock several oscillators together. Analytic theory, numerical simulations, and experiments describing the device are presented