Method for determining existence of wideband impedance matching circuit in a wireless IC device system

• US 10,089,502 B2
• Filed: 01/04/2016
• Issued: 10/02/2018
• Est. Priority Date: 05/26/2008
• Status: Expired due to Fees

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Kato, Noboru, Ishino, Satoshi
• Primary Examiner(s): Wang, Quan-Zhen
• Assistant Examiner(s): Burgdorf, Stephen
• Application Number:
  US14/986,771
• Publication Number:
  US 20160117531A1
• Time in Patent Office: 1,002 Days
• Field of Search: 340 101
• 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 19/0724 the arrangement being a circuit for communicating at a plurality of frequencies, e.g. for managing time multiplexed communication over at least two antennas of different types
• CPC Class Codes: G06K 19/07786 the antenna being of the HF type, such as a dipole
• 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 7/10148 the step consisting of dynamically tuning the resonant circuit of the interrogation device that is emitting the interrogation signal, e.g. for impedance matching inside of the interrogation device for tuning related to loop aerials in general H01Q7/00
• CPC Class Codes: G06K 7/10306 ultra wide band
• CPC Class Codes: H04B 5/24 Inductive coupling

Abstract

An accessory device to be mounted on a main device is provided with a wireless IC device. The main device is provided with a reader/writer that is an interrogator that communicates with the wireless IC device of the accessory device. When the accessory device is mounted on or about to be mounted on the main device, the reader/writer selects two or more frequencies in a frequency band in which an authentic wireless IC device can communicate to perform communication with the wireless IC device. With this configuration, even if the identification code written in an RFID tag is read and the RFID tag is duplicated, the duplicated RFID tag can be accurately and effectively determined as being counterfeit.

Claims

1. A method for determining authenticity of a wireless IC device in a system including the wireless IC device that is used as an RFID tag and an interrogator that communicates with the wireless IC device, the wireless IC device including a wideband impedance matching circuit and is configured to be capable of, by itself, processing signals having a plurality of frequencies in a widened frequency band that is wider than a frequency band of communication signals used by a standard RFID tag;

wherein the wideband impedance matching circuit comprises at least two helical inductors formed by conductive patterns on each of a plurality of substrate sheets, the conductive patterns of each sheet interconnected with the conductive patterns of the other sheets, the sheets laminated to form a multilayer circuit board;

the method comprising the steps of;

transmitting a first signal from the interrogator to the wireless IC device at a first frequency which is randomly selected, using the interrogator, within the widened frequency band that is established by the wideband impedance matching circuit;

transmitting a second signal from the interrogator to the wireless IC device at a second frequency which is randomly selected, using the interrogator, within the widened frequency band, the second frequency being different from the first frequency;

determining whether or not communication with the wireless IC device is possible at the first frequency and the second frequency; and

determining that the wireless IC device is authentic if communication is possible at both the first frequency and the second frequency.

2. The method for determining authenticity of the wireless IC device according to claim 1, wherein the interrogator selects two or more frequencies at which communication is to be performed.

3. The method for determining authenticity of the wireless IC device according to claim 1, wherein the widened frequency band in which the wireless IC device is capable of performing communication is in a range from 5 times or more to less than 1000 times the frequency band of the communication signals used by the standard RFID tag.

4. The method for determining authenticity of the wireless IC device according to claim 1, wherein the wireless IC device includes only a single wireless IC chip and only a single feeder circuit board on which the single wireless IC chip is mounted.