Influences of Aspect Ratio of Anode Mesh Wire on the Output of Virtual Cathode Oscillator

Virtual cathode oscillator (Vircator) is the simplest kind of high power microwave (HPM) source, it has only a cathode and mesh anode in the traditional axial Vircator, and it holds the record of highest output power. The disadvantage of Vircator has been its low energy conversion efficiency, however, recent Vircator with dielectric reflector has increased the efficiency to above 20%. With or without the dielectric reflector, the anode mesh is still an important part of Vircator. A high electron beam transmission ratio anode mesh usually means higher output power; however, the lifetime is also shorter for the anode mesh wire diameter is smaller, and it melts more easily. Also, the thickness of anode mesh wire affects the resonant Vircator frequency. In this particle-in-cell simulation, we simulate Vircator with anode mesh composed of solid rectangles. Under the same opening area ratio, different aspect ratio of the anode mesh means different thickness of the anode wires. We compare the output characteristics of various thickness anode mesh with the same opening area, and found they affect output power and output frequency considerably.