On radar cross section reduction effect by filamentary discharge in a dielectric barrier discharge

In Radar Cross Section (RCS) reduction as a military technology, dielectric barrier discharge (DBD) plasma is one of the most effective methods. For RCS reduction, it is reported that high plasma density over 1013/cm3 is required with high power and risk of thermal damage. For the practicality of plasma based RCSR technology, enough RCSR effect with low density plasma is required and the filamentary discharge can be a solution. In this article, RCS reduction by filamentary DBD plasma with relatively low average density is studied. Basically, DBD plasma can be operated in two modes, filament mode and diffused mode. In the case of filament mode, most of the discharge area is concentrated in the filament area, with high plasma density and current density. At first, filamentary discharge is observed in a DBD source using a high speed camera. The shape and distribution of the filaments are studied. By the computational simulation, a distinct RCS reduction effect over 15 dB is observed, which corresponds to the previous experimental results. A parametric study on RCS reduction by filaments is performed. As a result, for RCS reduction by plasma, discharges with a higher number of filaments are preferred.