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/sub 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 /spl plusmn/20/spl deg/, it is necessary to stabilize beam current with an accuracy of /spl plusmn/8.3%, beam voltage with an accuracy of /spl plusmn/4.65%, and external magnetic fields to within an accuracy of /spl plusmn/0.092%.