Experiments on a Disk-on-Rod Traveling Wave Tube Amplifier Driven by a Nonlinear Transmission Line Modulated Electron Beam

Experiments have demonstrated high-power amplification (100 MW class) from a traveling wave amplifier driven by a modulated electron beam. The modulated electron beam is generated by applying a modulated voltage pulse from a nonlinear transmission line (NLTL) to the cathode of the electron gun. The system showed that over the designed operating range of the disk-on-rod (DoR) TWT amplifier (1.2–1.4 GHz), the peak frequency of the amplifier output tracked the peak frequency of the NLTL to within ±2%; however, the output was not phase stable. Measured RF energy gain for this frequency regime ranged from 1.5 at 1.2 GHz up to 5.0 at 1.4 GHz).