IC tag communication system

• US 20070063845A1
• Filed: 03/02/2006
• Published: 03/22/2007
• Est. Priority Date: 09/22/2005
• Status: Active Grant

• Current Assignee: Toshiba Tec Corporation (Toshiba Corporation)
• Original Assignee: Toshiba Tec Corporation (Toshiba Corporation)
• Inventors: Ohishi, Satoshi
• Granted Patent: US 7,498,941 B2
• Time in Patent Office: Days
• US Class Current: 340/572.100
• 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 7/10356 using a plurality of antennas, e.g. configurations including means to resolve interference between the plurality of antennas
• CPC Class Codes: G08B 13/24 by interference with electromagnetic field distribution

Abstract

An IC tag communication system according to an aspect of the present invention includes: a plurality of reader antennas which receive radio waves emitted from an IC tag attached to an article, the radio waves being at least partly overlapped with each other; a plurality of readers which are connected respectively to the reader antennas; and a phase adjustment section for adjusting the phases of the radio waves that the reader antennas receive to each other.

Claims

1. An IC tag communication system comprising:

a plurality of reader antennas which receive radio waves emitted from an IC tag attached to an article, the radio waves being at least partly overlapped with each other;

a plurality of readers which are connected respectively to the reader antennas; and

a phase adjustment section for adjusting the phases of the radio waves that the reader antennas receive to each other.

2. The IC tag communication system according to claim 1, wherein

the plurality of reader antennas are a pair of reader antennas which are disposed toward a gate so as to be opposed to each other across the gate and which receive radio waves from an IC tag attached to an article passing through the gate, the radio waves being at least partly overlapped with each other.

3. The IC tag communication system according to claim 2, wherein

the IC tag is a passive-type IC tag.

4. The IC tag communication system according to claim 3, wherein

the phase adjustment section is provided in one of the gate readers and is controlled by a controller which is connected to the gate reader.

5. An IC tag communication system comprising:

first and second reader antennas which are disposed toward a gate so as to be opposed to each other across the gate and which receive radio waves emitted from an IC tag attached to an article passing through the gate, the radio waves being at least partly overlapped with each other;

a first gate reader connected to the first reader antenna;

a second gate reader connected to the second reader antenna; and

a controller which is connected to the first gate reader and which controls the first and second gate readers,

the first gate reader comprising;

a first antenna transmission/reception section which controls radio waves emitted from and received by the first reader antenna;

a first transmission/reception signal processing section which processes a transmission signal included in radio waves emitted from the first reader antenna and a reception signal included in radio waves received by the first reader antenna; and

a transmission/reception timing adjustment section which is connected to the second gate reader and which adjusts the transmission/reception timing between the first and second reader antennas, and

the second gate reader comprising;

a second antenna transmission/reception section which controls radio waves emitted from and received by the second reader antenna; and

a second transmission/reception signal processing section which processes a transmission signal included in radio waves emitted from the second reader antenna and a reception signal included in radio waves received by the second reader antenna.

6. The IC tag communication system according to claim 5, wherein

the IC tag is a passive-type IC tag.

7. The IC tag communication system according to claim 6, wherein

the transmission/reception timing adjustment section has a delay circuit capable of changing delay time manually or automatically.

8. An IC tag communication system comprising:

a plurality of reader antennas which receive radio waves from IC tags attached to a plurality of articles arranged on a shelf, the radio waves being at least partly overlapped with each other;

a plurality of readers connected respectively to the reader antennas; and

a phase adjustment section for adjusting the phases of the radio waves that the reader antennas receive to each other.

9. The IC tag communication system according to claim 8, wherein

the IC tag is a passive-type IC tag.

10. The IC tag communication system according to claim 9, wherein

the phase adjustment section is provided in one of the gate readers and is controlled by a controller which is connected to the gate reader.

11. The IC tag communication system according to claim 10, wherein

the reader antennas are driven by the readers to which they are respectively connected, and

the directions of the reader antennas can be changed.

12. The IC tag communication system according to claim 10, wherein

the directions of the reader antennas are fixed, and

the shelf is configured to be movable.