RFID TAG DEVICE, TAG IDENTIFICATION DEVICE AND RADIO COMMUNICATION SYSTEM

• US 20080157935A1
• Filed: 03/03/2008
• Published: 07/03/2008
• Est. Priority Date: 08/25/2004
• Status: Abandoned Application

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Wakayama, Shirou, DOI, Yusuke, Ishiyama, Masahiro, Ozaki, Satoshi
• Application Number:
  US12/041,522
• Publication Number:
  US 20080157935A1
• Time in Patent Office: Days
• US Class Current: 340/10.42
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• 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

An RFID tag device has a random number generator which generates a random number or a pseudo-random number, an identification information holding unit which holds identification information having a plurality of bits, a noise addition processing unit which generates noise-added identification information by conducting either of reversal from “0” of a bit decided based on the random number generated by the random number generator to “1” or reversal from “1” of the bit to “0”, among a plurality of bits included in the identification information, and a radio communication unit which transmits the noise-added identification information by radio.

Claims

1. A communication method of using an RFID tag device, comprising:

generating a random number or a pseudo-random number;

holding identification information having a plurality of bits;

generating noise-added identification information by conducting either of reversal from “

0”

of a bit decided based on the generated random number generator to “

1”

or reversal from “

1”

of the bit to “

0”

, among a plurality of bits included in the identification information; and

transmitting the noise-added identification information by radio.

2. The method according to claim 1, further comprising:

storing the generated random number in an temporary storage unit,

wherein the random number stored in the temporary storage unit is transmitted with the noise-added identification information by radio.

3. The method according to claim 1, further comprising:

measuring a time after transmitting the noise-added identification information,

wherein a subsequent noise-added identification information is transmitted when the measured time is a predetermined time or more.

4. The method according to claim 1, further comprising:

generating a noise relating to a noise included in the noise-added identification information,

wherein the generated noise is transmitted with the noise-added identification information by radio.

5. A communication method of using an RFID tag device, comprising:

holding a filter having a plurality of bits capable of probabilistically detecting whether or not a certain bit string is included in a group of bit strings;

generating a random number or a pseudo-random number;

generating a noise-added filter obtained by either of reversal from “

0”

of a bit decided based on the generated random number or reversal from “

1”

of a bit decided based on the generated random number among a plurality of bits included in the filter; and

transmitting the noise-added filter by radio.

6. The method according to claim 5, wherein the held filter is generated by using the identification information having a plurality of bits and a Hash function.

7. The method according to claim 5, wherein the held filter is a fixed bloom filter.

8. The method according to claim 5, wherein the noise-added filter is obtained by reversing “

0”

of a bit decided based on the random number generated by the random number generator to “

1”

, among the plurality of bits included in the held filter.

9. The method according to claim 5, further comprising:

selecting any of a plurality of filters held,

wherein the noise-added filter is generated corresponding to the selected filter.

10. The method according to claim 5, further comprising:

storing the generated random number in a temporary storage unit,

wherein the random number stored in the temporary storage unit is transmitted with the noise-added filter by radio.

11. The method according to claim 5, further comprising:

measuring a time after transmitting the noise-added filter,

wherein a subsequent noise-added filter is transmitted when the measured time is a predetermined time or more.

12. The method according to claim 5, further comprising:

generating a noise relating to a noise added to the noise-added filter,

wherein the noise generated by the noise generating is transmitted with the noise-added filter by radio.