SELECTABLE SECTORAL ANTENNA ARRAY USING A QUADRUPLE FEEDING NETWORK FOR ITEM-LEVEL TAGGING IN UHF RFID APPLICATIONS

Abstract

For avoiding a dead zone where the tag cannot be detected in the ultrahigh-frequency (UHF) radio frequency identification (RFID), a SELECTABLE SECTORAL ANTENNA ARRAY USING a QUADRUPLE FEEDING NETWORK FOR ITEM-LEVEL TAGGING IN UHF RFID APPLICATIONS is presented. The proposed antenna array consists of a 2 x 2 circular polarized quadrifilar spiral antenna array and a quadruple feeding network for multiple beams. It generates single, dual, and quad beams with a hemispheric coverage by a beam switching, and its maximum gain and 3 dB beamwidth are approximately 7.8 dBic and 60 degrees, respectively. Compared with the conventional antennas, the proposed antenna array provides the improved tag identification with the dead zone avoidance in the reading range.