IC-tag read-write apparatus

• US 20070257112A1
• Filed: 06/04/2007
• Published: 11/08/2007
• Est. Priority Date: 01/23/2004
• Status: Active Grant

• Current Assignee: Tatsuya Fujii
• Original Assignee: Tatsuya Fujii
• Inventors: Fujii, Tatsuya
• Granted Patent: US 7,374,089 B2
• Time in Patent Office: Days
• US Class Current: 235/451
• 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 7/10069 the collision being resolved in the frequency domain, e.g. by hopping from one frequency to the other frequency hopping or spread spectrum techniques H04B7/00

Abstract

A radio data communication apparatus includes first antennas, modulation circuits, an oscillating circuit, a switch circuit, a memory, and a control circuit. The first antennas perform a one-to-one radio communication with second antennas of IC tags having different communication frequencies. The one-to-one radio communication is carried out based on a resonance frequency uniquely assigned to each one of combinations between the first antennas and the second antennas. The memory stores communication information of each IC tag, including an assigned resonance frequency. The control circuit reads a resonance frequency assigned to a second antenna belonging to a target IC tag, generates the control signal such that the switch circuit selects a specific carrier wave having a frequency substantially equal to the resonance frequency read from the memory, and transmits the specific carrier wave and data to be transmitted in synchronism with each other to a corresponding modulating circuit.

Claims

1-8. -8. (canceled)

9. An IC-tag read-write apparatus comprising:

a plurality of first antennas configured to perform a one-to-one radio communication with a plurality of second antennas of IC tags having respective different communication frequencies;

a plurality of modulation circuits corresponding to the plurality of first antennas and each configured to modulate a carrier wave in accordance with data to be transmitted and transmitting the modulated carrier wave to a specific IC tag among the plurality of IC tags through a corresponding one of the plurality of first antennas;

a carrier wave generating circuit configured to generate a plurality of carrier waves having respective different frequencies;

a memory storing communication information of each one of the IC tags, including a resonance frequency assigned thereto; and

a control circuit configured to read from the memory a specific resonance frequency assigned to one of the plurality of second antennas belonging to a target IC tag among the IC tags, to generate a control signal;

a switch circuit configured to exclusively select one of the plurality of carrier waves from the carrier wave generating circuit in accordance with the control signal generated by the control circuit,

wherein said control signal causes the switch circuit to selects a specific carrier wave having a radio frequency substantially equal to the specific resonance frequency read from the memory, and transmit the specific carrier wave and data to be transmitted in synchronism with each other to a corresponding one of the plurality of modulating circuits.

10. The IC-tag read-write apparatus of claim 9, wherein the communication information stored in said memory for each IC tag includes data representing a communication protocol used by the IC tag.

11. The IC-tag read-write apparatus of claim 10, wherein said control circuit reads from the memory the data representing the communication protocol used by the target IC tag, and sends the data representing the communication protocol used by the target IC tag to the corresponding one of the plurality of modulating circuits.

12. The IC-tag read-write apparatus of claim 9, wherein said control circuit controls input and output of the data to be superimposed on the specific carrier wave.

13. The IC-tag read-write apparatus of claim 9, wherein each one of the plurality of first antennas is configured to have a frequency substantially equal to a specific resonance frequency of a corresponding one of the plurality of second antennas.

14. The IC-tag read-write apparatus of claim 13, wherein said one of the plurality of first antennas is arranged close to the corresponding one of the plurality of second antennas.

15. An IC-tag read-write apparatus comprising:

at least one component for performing a predetermined function and to which at least one IC tag is installed; and

a radio data communication mechanism which comprises;

a plurality of first antennas configured to perform a one-to-one radio communication with a plurality of second antennas of IC tags having respective different communication frequencies, the IC tags including the at least one IC tag;

a plurality of modulation circuits corresponding to the plurality of first antennas and each configured to modulate a carrier wave in accordance with data to be transmitted and transmitting the modulated carrier wave to a specific IC tag among the plurality of IC tags through a corresponding one of the plurality of first antennas;

a carrier wave generating circuit configured to generate a plurality of carrier waves having respective different frequencies;

a memory storing communication information of each one of the IC tags, including a resonance frequency assigned thereto; and

a control circuit configured to read from the memory a specific resonance frequency assigned to one of the plurality of second antennas belonging to a target IC tag among the IC tags, to generate a control signal;

a switch circuit configured to exclusively select one of the plurality of carrier waves from the carrier wave generating circuit in accordance with the control signal generated by the control circuit,

wherein said control signal causes the switch circuit to selects a specific carrier wave having a radio frequency substantially equal to the specific resonance frequency read from the memory, and transmit the specific carrier wave and data to be transmitted in synchronism with each other to a corresponding one of the plurality of modulating circuits.

16. The IC-tag read-write apparatus of claim 15, wherein the specific resonance frequency assigned to the one of the plurality of second antennas belonging to the target IC tag is selected in accordance with environmental conditions of a place where the target IC tag is mounted.

17. The IC-tag read-write apparatus of claim 15, wherein the specific resonance frequency assigned to the one of the plurality of second antennas belonging to the target IC tag is selected in accordance with one or more materials of a place where the target IC tag is mounted.