Research on origination of oscillations and microwave growth in weakly resonant RBWOs
Abstract
The origination of oscillations and microwave growth in weakly resonant relativistic backward wave oscillators (RBWOs) are investigated theoretically. First, we investigate the electromagnetic radiation of electrons during the oscillation starting process in RBWOs. It is found that the initial microwave power in the X band RBWO is at the level of 1 μW, and the X band RBWO needs about 6.0-16 ns when the output power reaches up to 1.0 GW theoretically. Furthermore, based on the nonlinear circuit, we simulate the microwave growth and obtain the analytical relationship between the starting time and quality factor of the RF cavity in the weakly resonant RBWO. It suggests that, for the weakly resonant RBWO, the effect of the quality factor on the starting process is more prominent. It can be estimated that, for the X band RBWO, the suitable quality factor of the RF cavity may be in the range of 20-40. The theoretical results agree well with particle-in-cell results.
- Publication:
-
Physics of Plasmas
- Pub Date:
- September 2017
- DOI:
- 10.1063/1.4990150
- Bibcode:
- 2017PhPl...24i3115Y