DESIGN TECHNIQUE OF A CIRCULARLY POLARIZED ANTENNA FOR UHF BAND RFID READER

摘要

PURPOSE: A circular polarization antenna design technology for an ultra high frequency (UHF) radio frequency identification (RFID) reader is provided to have a high tag recognition rate without regard to direction of a tag antenna by developing an antenna having an isotropy pattern characteristic using a zigzag slot which is optimally designed. CONSTITUTION: A circular polarization antenna design technology for a UHF RFID reader comprises: a micro strip line block (100) which is impedance matched (101) for having compatibility with multiple commercialized RFID readers; a phase difference signal generator block has phase difference of 90 degrees with an original signal using a hybrid connector (110); two strip lines having λ/2 length which are designed in order to be divided two straight line signals which have a same amplitude and have a right angle (120); and a radiation plate (130) in which a zigzag slot which is optimally designed is formed. [Reference numerals] (101) Microstrip Line (impedance matching); (AA) 90° phase difference signal generator; (BB) Radiation plate