A Simple Approach to Wideband Frequency Tuning in Gyrotron: Proof-of-Principle Demonstration

摘要

We demonstrate analytically that for short-cavity gyrotrons posses weaker sensitivity to electron velocity spread that allows us to use such a system for making the frequency tunable range wider through the excitation of a series of axial modes. Based on this approach the proof-of-principle experiment was performed using low-frequency gyrotron, and the 4 % tuning band was demonstrated at the 1-kW power level which is in a good agreement with simulations. The method of overlapping the power dips between the excitation zones of neighboring axial modes due to the shift of the tube position inside the solenoid is proposed and tested. The obtained results open the possibility of developing tunable high-frequency gyrotrons of medium power for a number of promising applications.