Design of a 100 kW gyro-TWT

A gyro-TWT is often plagued by absolute instabilities in lower order modes and even in the operating mode itself. These problems will be avoided by performing an experiment in the lowest order mode in cylindrical waveguide ( TE/sub 11/ ) and using a low a beam to excite a wave with large k/sub 11/. A gyroresionant wiggler WM partiany transform the axial velocity of a high quality Pierce beam into transverse velocity. A 100 keV, 5 A, /spl alpha/ = 0.5 bewn will generate 9 GHz rf in a 3 kG magnetic field. Magnetic tapering will be used to enchance the efficiency. The theoretical gam is predicted to be 60 dB with a bandwidth in excess of 20%.