Method of measuring distance bound using radio frequency identification (RFID) and system thereof

• US 9,134,413 B2
• Filed: 01/02/2013
• Issued: 09/15/2015
• Est. Priority Date: 08/29/2012
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Youn, Taek Young, Hong, Do Won
• Primary Examiner(s): Bugg, George
• Assistant Examiner(s): AKKI, MUNEAR T
• Application Number:
  US13/732,997
• Publication Number:
  US 20140062761A1
• Time in Patent Office: 986 Days
• Field of Search: 340 101- 106, 3405721-5729, 340/5.8, 342/44, 342/118, 713/168, 708/250
• US Class Current: 1/1
• CPC Class Codes: G01S 13/765 with exchange of information between interrogator and responder
• CPC Class Codes: G01S 13/78 discriminating between different kinds of targets, e.g. IFF-radar, i.e. identification of friend or foe G01S13/75, G01S13/79 take precedence
• CPC Class Codes: G06F 21/554 involving event detection and direct action
• CPC Class Codes: H04L 63/123 received data contents, e.g. message integrity
• CPC Class Codes: H04W 12/06 Authentication
• CPC Class Codes: H04W 12/12 Detection or prevention of fraud
• CPC Class Codes: H04W 12/122 Counter-measures against attacks; Protection against rogue devices
• CPC Class Codes: H04W 12/63 Location-dependent; Proximity-dependent

Abstract

A tag decides a response based on a plurality of queries received from a reader, determines whether to transmit the response, transmits the response to the reader according to the results of the determination, and transmits a message authentication code including communication content to the reader. The reader calculates a consumed time period which is the time difference between a transmission time at which the queries are transmitted and a reception time at which the response is received, calculates an average consumed time period of the consumed time period, and measures a distance to the tag based on the average consumed time period. Accordingly, it is possible to check an attacker'"'"'s intervention with a high probability, thereby improving distance measurement performance. Also, the tag may efficiently perform computing and communication.

Claims

1. A method in which a tag assists in measuring a distance bound, the method comprising:

receiving a plurality of queries from a reader;

deciding a response value based on a random number c_i included in each query of the plurality of queries and a first bit created in advance through protocol initialization with the reader;

determining whether or not to transmit a response including the response value based on a random number m_i included in each query of the plurality of queries and a second bit created in advance through the protocol initialization with the reader;

transmitting the response to the reader if it is determined that the response has to be transmitted; and

calculating a message authentication code based on the random number c_i, the random number m_i, and the response value, and transmitting the message authentication code to the reader.

2. The method of claim 1, further comprising:

performing the receiving of the plurality of queries, the deciding of the response value, the determining of whether or not to transmit the response including the response value, and the transmitting of the response, repeatedly, by a predetermined number of times, and

wherein the calculating of the message authentication code further comprises calculating the message authentication code based on c, m, and r, where c is all of c_i, m is all of m_i, and r is all of the response values, from the repeated pluralities of queries.

3. The method of claim 1, wherein the deciding of the response value comprises deciding the first bit or a bit complement of the first bit, as the response value, based on the random number c_i.

4. The method of claim 1, wherein the determining of whether or not to transmit the response comprises determining that the response is transmitted to the reader if the second bit is identical to the random number m_i, and determining that the response is not transmitted to the reader if the second bit is not identical to the random number m_i.

12. The method of claim 1, wherein the distance bound is measured by the reader based on a time difference between a transmission time of the plurality of queries and a reception time of the response.

5. A method in which a reader measures a distance bound, the method comprising:

selecting a plurality of queries and transmitting the plurality of queries to a tag, the plurality of queries comprising each query including a random number c_i and a random number m_i;

measuring a transmission time at which the plurality of queries are transmitted;

in response to the plurality of queries, receiving, depending on the random number m_i, at least one response r_i which is based on the random number c_i;

measuring a reception time at which the response is received, and

calculating a consumed time period which is a time difference between the transmission time and the reception time;

receiving from the tag a message authentication code which is based on the random number c_i, the random number m_i, and the response r_i, and verifying the message authentication code; and

calculating an average consumed time period of the consumed time period if it is determined that the message authentication code is correct based on the results of the verification.

6. The method of claim 5, further comprising:

performing the transmitting of the plurality of queries, the measuring of the transmission time, the receiving of the response, and the calculating of the consumed time period, repeatedly, by a predetermined number of times, and

wherein the receiving of the message authentication code further comprises receiving the message authentication code which is based on c, m, and r where c is all of c_i, m is all of m_i, and r is all of r_i, from the repeated pluralities of queries.

13. The method of claim 5, wherein the at least one response r_i is based on the random number c_i and a first bit created in advance through protocol initialization with the tag.

14. The method of claim 5, wherein the at least one response r_i is received depending on the random number m_i and a second bit created in advance through the protocol initialization with the tag.

15. The method of claim 5, wherein the at least one response r_i is based on the random number c_i and a first bit created in advance through protocol initialization with the tag, and the at least one response r_i is received depending on the random number m_i and a second bit created in advance through the protocol initialization with the tag.

16. The method of claim 5, further comprising:

performing the transmitting of the plurality of queries, the measuring of the transmission time, the receiving of the response r_i, and the calculating of the consumed time period, repeatedly, by a predetermined number of times, and

wherein the average consumed time period is calculated based on the consumed time periods that were repeatedly calculated.

7. A tag comprising:

a tag processor configured to decide a response value based on a random number c_i included in each query of a plurality of queries received from a reader and a first bit created in advance through protocol initialization, to determine whether or not to transmit a response including the response value to the reader based on a random number m_i included in each query of the plurality of queries and a second bit created in advance through the protocol initialization, to transmit the response according to the results of the determination, to calculate a message authentication code based on the random number c_i, the random number m_i, and the response value, and to transmit the message authentication code to the reader; and

a tag transceiver configured to communicate with the reader.

8. The tag of claim 7, wherein the tag processor repeatedly performs operation of deciding the response value based on a random number c_i included each query of a predetermined number of queries received from the reader and the first bit, operation of determining whether or not to transmit the response to the reader based on a random number m_i included in each query of the predetermined number of queries and the second bit, and operation of transmitting the response according to the results of the determination.

9. The tag of claim 7, wherein the tag processor decides the first bit or a bit complement of the first bit, as the response, based on the random number c_i.

10. The tag of claim 7, wherein the tag processor transmits the response to the reader if the second bit is identical to the random number m_i, and does not transmit the response to the reader if the second bit is not identical to the random number m_i.

11. The tag of claim 8, wherein the tag processor calculates the message authentication code based on c, m, and r where c is all of c_i, m is all of m_i, and r is all of r_i from the repeated pluralities of queries.