Significant pulse-lengthening in a multigigawatt magnetically insulated transmission line oscillator

The Air Force Research Laboratory/Phillips Laboratory magnetically insulated transmission line oscillator (MILO) is a gigawatt-class, L-band, high-power microwave tube driven by a 500-kV, 60-kA electron beam. A previous version of this tube generated 1.5 GW pulses, but with significant RF pulse shortening, The paper reports on improvements to the tube that have allowed us to increase the output power by 25% and to increase the RF pulse duration by a factor of two and a half.