Effect of Driving Frequency on Reduction of Radar Cross Section Due to Dielectric-Barrier-Discharge Plasma in Ku-Band

This study investigates the effect of driving frequency on the ability of a dielectric barrier discharge (DBD) plasma to reduce the radar cross section (RCS) in the Ku-band. Analysis based on the Drude model suggests that the electron density of the plasma will increase with the driving frequency, implying that the plasma will be more effective in terms of RCS reduction. Experimental results based on a multifingered DBD generator reveal that an RCS reduction of up to 4.1 dB is achieved at 18 GHz, which is a 1.3 dB increase due to increasing the driving frequency from 1 to 2 kHz. Finally, the electron density, which is extracted by fitting the simulated RCS results, increased by as much as approximately 330% due to the increase in the driving frequency from 1 to 2 kHz. As the driving frequency increases, the frequency of collision between plasma particles increases. Therefore, the ionization of gas molecules is enhanced, resulting in a higher electron density. The experimental results also suggest that enhancement in the RCS reduction is larger when the electric field intensity between the two electrodes of the DBD generator is greater. As a result, the plasma becomes electromagnetically more lossy and is more effective for reducing the RCS. Experimental results are provided and analyzed based on the electromagnetic parameters used for modeling the plasma.