Using the "MAGIC" code, computer simulation is performed to design a cathode structure which provides a radial distribution of electron beam density matching the field distribution of the TM05 mode. Thus, very narrow band TM05 mode microwave radiation can be generated in an open end waveguide. The simulation results show that the vircator can indeed be operated at the selected frequency 10.4 GHz with a very narrow bandwidth(∆ω/ω<1%).
"Simulation of a 10.4GHz TM05 vircator", Proc. SPIE 1576, 16th International Conference on Infrared and Millimeter Waves, 157603 (1 October 1991); doi: 10.1117/12.2297716; https://doi.org/10.1117/12.2297716