Mode analysis of output microwave for coaxial vircator oscillator

The microwave frequency of the coaxial vircator oscillator were 3.4 GHz and 3.7 GHz using different filtration efficienty of the anode mesh. Based on the experimental results, the beam distribution in the coaxial virtual cathode was analyzed. The eigenmode of the coaxial virtual cathode was calculated using resonance cavity theory, and the results were compared with the experimental ones. The conclusion is that the distribution the beam in the mesh has important effect on the output microwave mode. The output microwave frequency is the result of the interaction between the resonance cavity and the cathodeanode gap. The filtrate of the anode mesh also has important effect on the frequency, the filtration efficiency increase, the microwave frequency increased correspondingly．