RFID SYSTEM USING CIRCULAR POLARIZED ANTENNA

• US 20100231387A1
• Filed: 03/09/2010
• Published: 09/16/2010
• Est. Priority Date: 03/10/2009
• Status: Active Grant

• Current Assignee: LS Industrial Systems Company Limited
• Original Assignee: LS Industrial Systems Company Limited
• Inventors: Choo, Jae Yul, Ryoo, Jeong Ki, Hong, Jin Kuk
• Granted Patent: US 8,395,502 B2
• Time in Patent Office: Days
• US Class Current: 340/541
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: G06K 7/10346 the antenna being of the far field type, e.g. HF types or dipoles

Abstract

The present disclosure relates to an RFID (Radio frequency identification) system using circular polarized antennas, wherein a reader emits electromagnetic wave through reader antennas to recognize a tag and to read out customer information if a customer proximity is detected, where the reader antennas are installed at a kiosk body and at a rear proximity position of a floor surface on which a customer using the kiosk stands, and the reader antennas installed at the rear proximity position of the floor surface emits circular polarizing wave toward the kiosk, whereby the tag can be accurately recognized regardless of position of the tag of the customer.

Claims

1. An RFID (Radio frequency identification) system using circular polarized antennas, comprising:

a proximity sensor mounted at a kiosk for sensing whether a customer has proximately approached;

a customer detector configured to detect whether the customer has proximately approached the kiosk using a sensing signal of the proximity sensor;

a server configured to request customer information and provide the customer with services based on the customer information if the customer detector detects that the customer has approached the kiosk; and

a reader configured to recognize the tag by emitting an electromagnetic wave through a plurality of reader antennas if the server requests the customer information and to read out the customer information stored in the tag that has recognized the customer and to provide the read-out customer information to the server.

2. The system of claim 1, wherein the plurality of reader antennas comprises:

a first reader antenna and a second reader antenna each mounted at an upper portion and a middle portion of a kiosk body; and

a third reader antenna mounted at a rear proximity position of a floor surface on which the customer currently using the kiosk stands.

3. The system of claim 2, wherein the third reader antenna slantingly emits the electromagnetic wave toward the kiosk body.

4. The system of claim 3, wherein the slanted emission angle of the electromagnetic wave is within a range of 10°

˜

30°

based on a perpendicular line.

5. The system of claim 2, wherein the third reader antenna is formed with a plurality of circular polarized antennas of 2×

2 array, where a circular polarized antenna arranged near the kiosk and another circular polarized antenna arranged far from the kiosk have mutually different phases.

6. The system of claim 5, wherein a signal phase delay value applied to the plurality of circular polarized antennas of 2×

2 array is 0 for two circular polarized antennas positioned at a rear based on the kiosk body, and a range of −

45°

˜

−

65°

for two circular polarized antennas positioned at the front.