A new X-band coaxial transit-time oscillator

A new structure of a high power microwave oscillator based on the transit-time instability is proposed and studied numerically in this paper. Due to its coaxial structure with large radius, the oscillator allows larger input and output power and can work at higher frequency. With no external magnetic field being used for beam focusing, it keeps the simplicity of a conventional transit-time oscillator. Using an electron beam of 180 kV and 10 kA, a stable and monochromatic output with peak power of 700 MW is achieved by simulation at 8.35 GHz with an rms efficiency of 20%. (C) 2002 American Institute of Physics.