UHF electrically large near-field RFID reader antenna using segmented loop unit

An ultra high frequency (UHF) electrically large near-field RFID reader antenna using segmented loop unit is proposed to enlarge the interrogation zone. The proposed antenna is composed of two segmented loops with one common side and a feeding network. Each loop has a uniform and single direction flowing current itself. By providing reverse-direction flowing current to the two segmented loops, the strong and uniform magnetic field distribution over a large interrogation zone can be achieved.