Phase stability of a two-stage W-band TE/sub 01/ gyro-traveling-wave-tube with distributed loss and tapered magnetic field

Phase stability of a W-band TE 01 gyro-traveling-wave-tube (Gyro-TWT) with distributed loss and tapered magnetic field is studied in this paper. The phase sensitivity of electron beam voltage, current, and magnetic field is analyzed by using nonlinear theory. The influences on phase stability of important factors such as distributed loss, tapered magnetic field, and input frequency are presented. The results show that relations between phase deviation and electron beam parameters may be expressed by a linear equation. In addition, to maintain phase stability with a maximum accuracy of plusmn20deg, it is necessary to stabilize beam current with an accuracy of plusmn8.3%, beam voltage with an accuracy of plusmn4.65%, and external magnetic fields to within an accuracy of plusmn0.092%