Full-wave modeling of antennas by elementary sources based on spherical waves translation

A full-wave model of space limited antennas in terms of elementary sources of colocalized infinitesimal dipoles is introduced. In the first step the antenna is characterized by means of a generalized scattering matrix in terms of spherical modes. Afterwards, a generalized scattering matrix in terms of elementary sources of colocalized infinitesimal dipoles is obtained by using rotation and translation properties of spherical modes. In this way, an accurate and simpler full-wave model for the antenna is achieved.