Electromagnetic scattering from impedance-matched bodies

Electromagnetic scattering from impedance bodies with the surface impedance equal to the wave impedance of the surrounding medium shows a number of extremal features, including vanishing axial backscattering cross section in the case of arbitrarily sized bodies of revolution. This paper examines various scattering cross sections (mono- and bistatic, total scattering, absorption and extinction) of electrically large arbitrarily shaped impedance-matched bodies, and it is shown that the backscattering cross section of such bodies vanishes in the optical limit. Furthermore, it is conjectured that considered as functions of the surface impedance, the mean total scattering cross section has a global minimum and the mean absorption cross section a global maximum when the body is illuminated by plane waves with random incidence direction and polarization.