Abstract: An embodiment of the present invention provides an antenna system, comprising a plurality of non-uniformly spaced antenna elements arranged substantially linearly, a power divider for dividing transmit power thereby coupling signals to the plurality of antenna elements, a phase shifter capable of phase shifting the signals between the power divider and the plurality of antenna elements such that radiated signals from each antenna element add coherently such that the radiated electromagnetic energy may be focused at a focal point in the near field region or in the Fresnel region of the antenna system. An embodiment of the present invention may also provide at least one additional receive antenna element capable of receiving signals backscattered from at least one RFID tag located in the near field of the focused array and the divider may create substantially equal power levels feeding each antenna element.

Abstract: An apparatus capable of tracking a target, comprising at least one near-field focused antenna comprising an array of elements and a phase shifter to form multiple fixed beams in the near-field, a sensor capable of sensing the location of the target, and a controller capable of accepting position information and capable of activating the proper fixed beam along a course so as to enable the near-field focused beams to track the target. The array of elements may be substantially linear and the sensor may be optical, mechanical, thermal, or sonic position detection subsystems. In an embodiment of the present invention the target may be at least one RFID tag and the phase shifter may include a voltage tunable dielectric. The controller may control a plurality of switches which activate at least one beam forming network. Further, the tracking may occur along a predetermined course, and the predetermined course may be along a conveyor line or through a doorway.