Interrogator, transponder and transponder identification method

• US 20070200677A1
• Filed: 08/16/2006
• Published: 08/30/2007
• Est. Priority Date: 02/10/2006
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Murano, Tomomitsu
• Granted Patent: US 8,193,910 B2
• Time in Patent Office: Days
• US Class Current: 340/10.310
• 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 7/10049 binary tree

Abstract

There is provided an interrogator, transponder, and transponder identification method, which shorten processing time for identification. An interrogator that makes wireless communication with a transponder, comprising: a temporary number specify section that transmits a request for transmission of a unit bit string as a bit string having a predetermined length in a bit string expressing a temporary number owned by the transponder, receives a unit bit sting transmitted from the transponder in response to the request, and specifies the temporary number of the transponder, based on the unit bit string; and an identification information obtaining section that transmits, if a temporary number of a transponder is specified by the temporary number specify section, a request for transmission of identification information of the transponder to the transponder, and receives the identification information transmitted from the transponder, in response to the request.

Claims

1. An interrogator that makes wireless communication with a transponder, comprising:

a temporary number specify section that transmits a request for transmission of a unit bit string as a bit string having a predetermined length in a bit string expressing a temporary number owned by the transponder, receives a unit bit string transmitted from the transponder in response to the request, and specifies the temporary number of the transponder, based on the unit bit string; and

an identification information obtaining section that transmits, if a temporary number of a transponder is specified by the temporary number specify section, a request for transmission of identification information of the transponder to the transponder, and receives the identification information transmitted from the transponder, in response to the request.

2. The interrogator according to claim 1, wherein the temporary number specify section receives plural kinds of unit bit strings transmitted from the transponder, distinguishing the plural kinds of unit bit strings from one another.

3. The interrogator according to claim 1, wherein the temporary number specify section stores received unit bit strings connected with one another, as a temporary number bit string.

4. The interrogator according to claim 3, wherein if plural kinds of unit bit strings are received from a transponder, the temporary number specify section transmits a multi-reception acknowledgement to the transponder, the acknowledgement acknowledging reception of the plural kinds of unit bit strings.

5. The interrogator according to claim 4, wherein if plural kinds of unit bit strings are received from a transponder, the temporary number specify section decides priority order of the plural kinds of the unit bit strings, based on preset priority order of the unit bit strings, stores, as a temporary number stack, the temporary number bit string added with another unit bit string than the most prioritized unit bit string among the plural kinds of unit bit strings, and stores, as a new temporary number bit string, the temporary number bit string added with the most prioritized unit bit string among the plural kinds of unit bit strings.

6. The interrogator according to claim 5, wherein if identification information of a transponder is received by the identification information obtaining section and if any bit string whose temporary number has not yet been specified exists still in the temporary number stack, the temporary number specify section specifies a new temporary number, using the newest bit string in the temporary number stack as a temporary number bit string.

7. The interrogator according to claim 1, wherein the temporary number is shorter information than the identification information.

8. A transponder that makes wireless communication with an interrogator, comprising:

a temporary number generation section that generates a temporary number;

a unit bit string transmitter that transmits, if a request for transmission of a unit bit string as a bit string having a predetermined length in a bit string of a temporary number, the unit bit string; and

an identification information transmitter that transmits, if a request for transmission of identification information is received from the interrogator, the identification information to the interrogator.

9. The transponder according to claim 8, wherein if the unit bit string transmitter receives a multi-reception acknowledgement from the interrogator, the acknowledgement acknowledging that plural kinds of unit bit strings have been received, the unit bit string transmitter performs setting of a queue counter, based on a unit bit string transmitted just before and based on preset priority order of unit bit strings.

10. The transponder according to claim 9, wherein the unit bit string transmitter receives a multi-reception acknowledgement or a request for transmission of a next unit bit string, from the interrogator, and transmits the next unit bit string if the queue counter indicates zero.

11. The transponder according to claim 8, wherein the unit bit string transmitter performs transmission, using a slot corresponding to the unit bit string.

12. The transponder according to claim 8, wherein the temporary number is shorter information than the identification information.

13. A transponder identification method by which identification of a transponder is performed by wireless communication between an interrogator and the transponder, comprising:

a temporary number generation step of the transponder that generates a temporary number;

a unit bit string request transmission step of the interrogator that transmits a request for transmission of a unit bit string as a bit string having a predetermined length in a bit string of a temporary number owned by the transponder;

a unit bit string transmission step of the transponder that transmits the unit bit string if the request transmitted by the temporary number request step is received;

a temporary number specify step of the interrogator that receives the unit bit string transmitted by the temporary number transmission step, and specifies the temporary number of the transponder, based on the unit bit string;

an identification information transmission request transmission step of the interrogator that transmits a request for transmission of identification information of the transponder to the transponder if the temporary number of the transponder is specified by the temporary number specify step;

an identification information transmission step of the transponder that transmits the identification information to the interrogator if the request transmitted by the identification information request step is received; and

an identification information reception step of the interrogator that receives the identification information transmitted by the identification information request step.

14. The transponder identification method according to claim 13, wherein the temporary number specify step receives plural kinds of unit bit strings, distinguishing the plural kinds of unit bit strings from one another.

15. The transponder identification method according to claim 13, wherein the temporary number specify step stores received unit bit strings connected with one another, as a temporary number bit string.

16. The transponder identification method according to claim 15, wherein if plural kinds of unit bit strings are received from a transponder, the temporary number specify step transmits a multi-reception acknowledgement to the transponder, the acknowledgement acknowledging reception of the plural kinds of unit bit strings.

17. The transponder identification method according to claim 16, wherein if plural kinds of unit bit strings are received from a transponder, the temporary number specify step decides priority order of the plural kinds of the unit bit strings, based on preset priority order of the unit bit strings, stores, as a temporary number stack, the temporary number bit string added with another unit bit string than the most prioritized unit bit string among the plural kinds of unit bit stings, and stores, as a new temporary number bit string, the temporary number bit string added with the most prioritized unit bit string among the plural kinds of unit bit strings.

18. The transponder identification method according to claim 17, wherein if identification information of a transponder is received by the identification information obtaining step and if any bit string whose temporary number has not yet been specified exists still in the temporary number stack, the temporary number specify step is executed again to specify a new temporary number, using the newest bit string in the temporary number stack as a temporary number bit string.

19. The transponder identification method according to claim 18, wherein if the unit bit string transmission step receives a multi-reception acknowledgement from the interrogator, the acknowledgement acknowledging that plural kinds of unit bit strings have been received, the unit bit string transmission step performs setting of a queue counter, based on a unit bit string transmitted just before and based on preset priority order of unit bit strings.

20. The transponder identification method according to claim 19, wherein the unit bit string transmission step receives a multi-reception acknowledgement or a request for transmission of a next unit bit string, from the interrogator, and transmits the next unit bit string if the queue counter indicates zero.