Characterization of modes in coaxial vircator

Abstract

Modes' character of high-power microwave (HPM) pulses generated in coaxial vircator is discussed. The electromagnetic (EM) field gains due to beam-wave interaction for TM/sub 01/ and TE/sub 11/ modes are derived according to the E-field distribution pattern inside the anode cavity. Two-and-a-half dimensional (2.5-D) and three-dimensional (3-D) computer simulations are carried out to determine the main mode under different numerical simulation coordinate systems. Finally, the experimental verification is obtained by two different diagnostic methods. The results indicate that for most cases, the TE/sub 11/ mode dominates the output power in the coaxial vircator studied.