Recent advances in theory and performance of millimeter-wave magnetrons

Spatial-harmonic magnetrons with a cold secondary-emission cathode are candidates for pulsed high-power sources in the 3-mm and 2-mm wave frequency bands and even below. We have recently developed a nonlinear beam-field interaction model in order to optimise their performance and to study the frequency and power limits. Both simulated and experimental results promise excellent performance of such miniaturized tubes which have reached a mature state for radar applications in the 2-mm wave band.