The Ineffectiveness of Absorbing Coatings on Conducting Objects Illuminated by Long Wavelength Radar

Theoretical and experimental electromagnetic scattering results are presented concerning the effects of applying thin coatings to perfectly conducting scatterers. Most of the paper is concerned explicitly with spheres and cones. It is shown that thin coatings can have little effect on the Rayleigh scattering cross sections. It is also pointed out how the effect of conductivity is enhanced at low frequencies and how, as a consequence, a thin slightly lossy spherical shell scatters like a perfectly conducting sphere in the Rayleigh region.