Modulation of Microwave Reflection by Grid Electrode DC Glow Discharge

In recent decades, research on the interaction between plasma and electromagnetic waves has garnered significant attention due to its enormous potential applications in communication, aerospace, and industry. To further investigate the propagation characteristics of electromagnetic waves in plasma, this study designed a device that generates plasma through grid electrode DC glow discharge in a helium environment. The research focused on the I-V characteristics of grid electrode discharge under different gas pressures and the modulation effect of the generated plasma on microwave reflection at frequencies ranging from 2 to 18GHz. Experimental results indicate that with an increase in helium pressure, the slope of the I-V characteristics curve of the discharge electrode shows a decreasing trend. The introduction of plasma demonstrates modulation effects on microwave reflection at frequencies centered around 5, 10, and 14GHz, manifesting as enhanced reflection, suppressed reflection, and enhanced reflection, respectively. Increasing helium pressure suppresses the modulation effect of the plasma generated by grid electrode discharge on microwave reflection. These findings can contribute to the development of applications such as reentry communication interruption and plasma stealth.