Decomposition of electrically small resonant antennas into their electric and magnetic part by far field polarisation analysis

A new kind of field representation on the far field sphere is presented. This representation is based upon the polarisation states of the field. Polarisation states might easily be obtained upon determining the peculiar loci in the field. It is demonstrated that, depending on the polarisation state of the field, either the magnetic or the electric dipole moment is dominant. Subsequently, criteria which may be applied to determine which dipole moment is responsible for the main radiation are derived. This characterization scheme which is a good figure of merit for an antenna designer may be useful in mobile communication to avoid possible adverse effects of RF fields on human health.