Relativistic BWO with resonant reflector

Summary form only given. The paper presents the theoretical and experimental studies of an X-band BWO having the electrodynamic system with a resonant reflector which serves for reflection of the backward wave and output of microwave power towards the collector edge of the tube. As in the majority of relativistic BWOs, the lowest axisymmetric TM-wave of a circular waveguide is used as the operating wave. However, instead of the traditional beyond cutoff-neck (having the diameter /spl sim/0.7 /spl lambda/), a short resonant cavity-a circular slot-is used as a reflector. The low-Q oscillation is formed by the "locked" wave TM/sub 02/ and therefore the minimum diameter of the system can rise up to /spl sim/1.5 /spl lambda/.