Characteristics of pulsed virtual cathode oscillator for nitrogen gas

Abstract EN

The Pulsed Virtual Cathode Oscillator is considered as a high power microwave source with transient characteristics dependant on the diode geometry and the pulsed power system driving the vacuum diode.

In this experiment, the pulsed axially virtual Cathode Oscillator is designed and operated at working nitrogen gas pressure 1 torr.

The system consists of a copper solid disc cathode and copper mesh anode .

Both two electrodes have the same diameter 4cm, and a glass ring of 0.4 cm thickness is fixed between the mesh anode and the cathode disk to keep the distance between them.

The electrical characteristics of pulsed axially Virtual Cathode Oscillator showed that the inductance and resistance of system are 2.88μH and 21.4 mΩ respectively.

Theoretically, the maximum discharge current equals to 1.48 KA for 7.6KV charging voltage, while the measured experimental discharge current equals to 1.27KA with plasma inductance of 13μH.

The virtual Cathode is formed at axial distance of 3 cm from the mesh anode and signal waveform illuminated electromagnetic radiation at various charging voltage and different distances.