Dual-loop near-field antenna for RFID label printer applications

A novel dual-loop near-field antenna for reliably writing or verifying information on loop-type UHF radio-frequency identification (RFID) labels bonded to a roll is presented. A resistor and inductor-loaded dual-loop is fed by specially designed coaxial feeding structure. The proposed antenna can reliably write or read information on a label just above its aperture while discriminating labels laterally offset from its aperture by 20 mm.