Experimental investigation on radar cross section reduction of plasma covered cavity

A certain number of standard commercial fluorescent lamps were placed directly against one another around the inner surface of a metal cavity to produce a plasma layer there. The scattering of microwaves with a series of incident angles by the plasma covered metal cavity was studied experimentally. The strong loss of return microwave observed is as large as 5 to 25 dB in the frequency range from 0.80 to 1.75 GHz, and trends to a peak of 26.71 dB when the frequency of incident wave approaching to 1.75 GHz. The incident angles where the best attenuation appears are different with different incident wave frequencies. The effects of plasma on microwave attenuations were analyzed. It can be drawn that the plasma has potential in radar cross section reduction of cavity structures like inlets.