THE NEAR-FIELD READER ANTENNA FOR 900MHZ BAND RFID

摘要

The present invention relates a 900-MHz band near-field RFID reader antenna. The 900-MHz band near-field RFID reader antenna comprises: a radiator having a plurality of antenna patterns each having a thickness (L1, based on impedance matching criteria) of a radiator pattern and repetitively formed at vertically constant radiator intervals (L2) and uniform radiation patterns formed by setting the constant radiator interval (L2) toλ/2 or less with reference to a resonant frequency (f) of an antenna, wherein the radiator is connected to a 50-Ωhorizontal feeder at a vertically middle position of the radiator and radiates a signal of an RFID reader in a tag direction; a feeding unit ground plane which is a plane for grounding the 50-Ωfeeder connecting the signal of the RFID reader to the vertical radiator of the antenna; and a reflector for offsetting a back lobe and a side lobe. In the radiator, a dielectric substrate (FR4) is formed to have a multi-layer structure to minimize the back lobe and the side lobe. Therefore, a false recognition rate of the RFID reader is reduced. [Reference numerals] (20) Feeding unit; (a) Front view; (AA) Radiator; (b) Side view; (CC) Reflector; (DD) Air layer; (EE) Ground plane; (FF) Designed 900-MHz near-field RFID reader