Towards 3-D Vector Intensity Focusing of Near and Far Fields

A new approach to the problem of focusing the intensity of vector fields into a target point (subject to sidelobe constraints elsewhere) is proposed. While allowing the adoption of completely arbitrary array antennas as radiating systems, the method exploits a nested optimization procedure properly acting on both the field polarization on the target point and the array excitations. By so doing, it is able to improve the performances of existing procedures (that usually handle scalar fields) and to deal with both the near-field (NF) and the far-field (FF) focusing problems in complex inhomogeneous 3-D media.