Design of a W-band TE01 mode gyro-TWT amplifier with a lossy ceramic-loaded circuit

A pulse prototype of a W-band TE
₀₁
mode gyrotron traveling-wave tube (gyro-TWT) amplifier is designed, and it features high gain and broadband capabilities. Theoretical investigation predicts that, when the magnetic injection gun (MIG) is optimized to generate an electron beam of voltage 70 kV, current 3 A, high pitch factor 1.5, and low axial-velocity spread about 5%, the gyro-TWT amplifier is of excellent performance, including being driven to saturation with input power P
_in
<;0.4 W, highest efficiency of 32.4%, and the bandwidth of 4.2 GHz with output power exceeding 50 kW.