An end-fire dipole array for big interrogation zone of near-field RFID

In this paper, an end-fire dipole array is firstly proposed for near-field UHF band RFID. The array is composed of three identical “H-shape” elements, and every “H-shape” element is composed of two identical dipoles with opposite directed currents. By adjusting the current phases on the six dipoles, the uniformity of the near-field is improved and a big interrogation zone of about 6λ in perimeter is achieved.