Near-field centripetal scattering from dielectric spheres

The fields scattered from small dielectric spheres illuminated by a plane wave have been computed as part of a study of spherical dielectric antennas. Studies of scattering of 3 cm wavelength from a 6.6 cm diameter sphere of dielectric constant between 2 and 3 show large regions on the surface of the sphere where the Poynting vector is inwardly directed. These regions form sidelobes of inwardly directed power density between the sidelobes of outwardly directed power density in the principal planes. Away from the sphere the angular extent of the centripetal power flow is reduced until they disappear at 2-3 cm from the surface.