Wireless communication device

• US 20050170793A1
• Filed: 12/29/2004
• Published: 08/04/2005
• Est. Priority Date: 02/03/2004
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Nakagawa, Atsushi
• Granted Patent: US 7,515,925 B2
• Time in Patent Office: Days
• US Class Current: 455/116
• 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

Abstract

A reader/writer of a wireless communication device transmits a carrier signal from an antenna, and if there is not response from an IC card within a preset time after transmitting the polling command, the carrier signal is temporarily controlled to an OFF state.

Claims

1. A wireless communication device comprising:

an antenna configured to carry out a wireless communication with a communication object;

a carrier wave transmitting unit configured to transmit via the antenna a carrier wave to a communication object located in a communication ready area from the antenna as a base point, the carrier wave serving to render the communication object to generate electric power for the communication;

a carrier wave control unit configured to periodically control the carrier wave transmitted from the carrier wave transmitting unit in a temporary off manner.

2. The wireless communication device according to claim 1, further comprising:

a signal receiving unit configured to receive via the antenna a response signal transmitted in reply to the carrier wave from the communication object in the communication ready area,

wherein the carrier wave control unit temporarily sets the carrier wave to an OFF state when the signal receiving unit does not receive the response signal within a certain period of time after the carrier wave transmitting unit transmits the carrier wave.

3. The wireless communication device according to claim 1, further comprising:

a command transmitting unit configured to transmit command data to the communication object,

wherein the carrier wave control unit temporarily sets the carrier wave to an OFF state each time a polling command is transmitted from the command transmitting unit.

4. The wireless communication device according to claim 1, further comprising:

a command transmitting unit configured to transmit command data to the communication object carried on the carrier wave; and

a signal receiving unit configured to receive via the antenna a response signal transmitted in reply to the carrier wave from the communication object in the communication ready area,

wherein the carrier wave control unit temporarily sets the carrier wave to an OFF state when the signal receiving unit does not receive the response signal within a certain period of time after the command transmitting unit transmits the polling command carried on the carrier wave.

5. A wireless communication device comprising:

a plurality of antennas configured to carry out a wireless communication with a communication object;

a switching unit configured to switch over between the plurality of antennas;

a carrier wave transmitting unit configured to transmit via the switched-over antenna a carrier wave to a communication object located in a communication ready area from the switched-over antenna as a base point, the carrier wave serving to render the communication object to generate electric power for the communication;

a carrier wave control unit configured to periodically control the carrier wave transmitted from the carrier wave transmitting unit in a temporary off manner.

6. The wireless communication device according to claim 5, wherein the switching unit switches the plurality of antennas over between them while the carrier wave control unit is setting the carrier wave to an OFF state.

7. The wireless communication device according to claim 5, wherein the carrier wave control unit controls the carrier wave in a temporary off manner each time the switching unit switches the plurality of antennas over between them.

8. The wireless communication device according to claim 5, further comprising:

a signal receiving unit configured to receive a response signal transmitted in reply to the carrier wave from the communication object in the communication ready area created from the antenna switched over by the switching unit via the switched antenna,

wherein the carrier wave control unit temporarily sets the carrier wave to an OFF state when the signal receiving unit does not receive the response signal within a certain period of time after the carrier wave transmitting unit transmits the carrier wave via the switched antenna, and

the switching unit switches the plurality of antennas over between them while the carrier wave control unit is setting the carrier wave to an OFF state.

9. The wireless communication device according to claim 5, further comprising:

a command transmitting unit configured to transmit command data to the communication object while carrying the command data on the carrier wave,

wherein the carrier wave control unit temporarily sets the carrier wave transmitted from the carrier wave transmitting unit to an OFF state each time a polling command is transmitted from the command transmitting unit, and

the switching unit switches the plurality of antennas over between them while the carrier wave control unit is setting the carrier wave to an OFF state.

10. The wireless communication device according to claim 5, further comprising:

a command transmitting unit configured to transmit command data to the communication object while carrying the command data on the carrier wave; and

a signal receiving unit configured to receive a response signal transmitted in reply to the carrier wave from the communication object in the communication ready area created from the antenna switched over by the switching unit via the switched antenna,

wherein the carrier wave control unit temporarily sets the carrier wave to an OFF state when the signal receiving unit does not receive the response signal within a certain period of time after the command transmitting unit transmits the polling command carried on the carrier wave via the switched antenna, and

the switching unit switches the plurality of antennas over between them while the carrier wave control unit is setting the carrier wave to an OFF state.

11. A wireless communication device comprising:

an antenna configured to carry out a wireless communication with a communication object;

a carrier wave transmitting unit configured to transmit via the antenna a carrier wave to a communication object located in a communication ready area from the antenna as a base point, the carrier wave having a level exceeding a threshold level that can render the communication object to generate electric power for the communication; and

a carrier wave control unit configured to periodically set the level of the carrier wave transmitted from the carrier wave transmitting unit temporarily lower than the threshold level.

12. The wireless communication device according to claim 11, further comprising:

a signal receiving unit configured to receive via the antenna a response signal transmitted in reply to the carrier wave from the communication object in the communication ready area,

wherein the carrier wave control unit temporarily sets the carrier wave to a level lower than the threshold level when the signal receiving unit does not receive the response signal within a certain period of time after the carrier wave transmitting unit transmits the carrier wave.

13. The wireless communication device according to claim 11, further comprising:

a command transmitting unit configured to transmit command data to the communication object,

wherein the carrier wave control unit temporarily sets the carrier wave to a level lower than the threshold level each time a polling command is transmitted from the command transmitting unit.

14. The wireless communication device according to claim 11, further comprising:

a command transmitting unit configured to transmit command data to the communication object while carrying the command data on the carrier wave; and

a signal receiving unit configured to receive via the antenna a response signal transmitted in reply to the carrier wave from the communication object in the communication ready area,

wherein the carrier wave control unit temporarily sets the carrier wave to a level lower than the threshold level when the signal receiving unit does not receive the response signal within a certain period of time after the command transmitting unit transmits the polling command carried on the carrier wave.

15. The wireless communication device according to claim 11, further comprising:

at least one antenna identical to the antenna; and

a switching unit configured to switch over between the plurality of antennas;

wherein the carrier wave control unit periodically sets the carrier wave transmitted from the carrier wave transmitting unit temporarily to a level lower than the threshold level via the antenna switched over by the switching unit.

16. The wireless communication device according to claim 15, wherein the carrier wave control unit temporarily sets the carrier wave to a level lower than the threshold level each time the switching unit switches the plurality of antennas over between them.

17. The wireless communication device according to claim 15, further comprising:

a signal receiving unit configured to receive a response signal transmitted in reply to the carrier wave from the communication object in the communication ready area created from the antenna switched over by the switching unit via the switched antenna,

wherein the carrier wave control unit temporarily sets the carrier wave to a level lower than the threshold level when the signal receiving unit does not receive the response signal within a certain period of time after the carrier wave transmitting unit transmits the carrier wave via the switched antenna.

18. The wireless communication device according to claim 15, further comprising:

a command transmitting unit configured to transmit command data to the communication object while carrying the command data on the carrier wave,

wherein the carrier wave control unit temporarily sets the carrier wave transmitted from the carrier wave transmitting unit to a level lower than the threshold level each time a polling command is transmitted from the command transmitting unit.

19. The wireless communication device according to claim 15, further comprising:

a command transmitting unit configured to transmit command data to the communication object while carrying the command data on the carrier wave; and

a signal receiving unit configured to receive a response signal transmitted in reply to the carrier wave from the communication object in the communication ready area created from the antenna switched over by the switching unit via the switched antenna,

wherein the carrier wave control unit temporarily sets the carrier wave to a level lower than the threshold level when the signal receiving unit does not receive the response signal within a certain period of time after the command transmitting unit transmits the polling command carried on the carrier wave via the switched antenna.