Patent ID: 8451125

Claim:
A reader based on Radio Frequency Identification (RFID), the reader comprising: a gate frame discretely installed at both sides of an entrance and exit; a parabolic surface reflective plate perpendicularly installed inside of the gate frame; an array antenna arranged on the parabolic surface reflective plate for receiving tag information transmitted from an RFID tag; an RFID reader unit for controlling an operation of the array antenna and converting the tag information received from the array antenna to tag data; a proximity sensor formed at the gate frame to detect an object approaching a gate; and a controller configured to control operation of the RFID reader unit and to determine an in/out state of an RFID tag by analyzing the tag data transmitted from the RFID reader unit when the object is detected by the proximity sensor, wherein the parabolic surface reflective plate is provided in a parabolic surface with a plurality of curvatures and is provided with antennas on a plain surface between the curvatures, and wherein the array antenna includes a plurality of small antennas, each small antenna being arranged on the parabolic surface reflective plate in a matrix.