A W-band gyrotron travelling wave amplifier using a helically corrugated waveguide

A gyrotron traveling wave amplifier (gyro-TWA) with a cusp electron gun and a helically corrugated waveguide operating in the W-band is presented. The large orbit electron beam from the cusp gun interacts resonantly with an ideal eigenwave existing in the interaction region based on the cyclotron resonance maser instability. When driven by the electron beam of energy 40 keV and current 1.5 A, the amplifier was simulated to output 10 kW (CW) with a 3 dB frequency bandwidth of 90-100 GHz and saturated gain of 40 dB. Linear analysis and numerical simulations of the performance characteristics of the amplifier will be presented.