Effect of rotational invariance on the monostatic characteristics of matched bodies.

It is shown analytically and numerically that a matched epsilon = mu reciprocal object with rotational symmetry will not produce any backscattering when illuminated along the axis of symmetry unless the body is invariant un der a rotation by 180 degrees. The purpose of this work is to generalize the monostatic theorem of Weston to arbitrary rotational symmetry, thereby providing a basic rule for scattering by complex bodies. The theory is illustrated by application to a few selected scatterers.