Inspection method and inspection device for RFID tag

• US 10,235,544 B2
• Filed: 05/01/2014
• Issued: 03/19/2019
• Est. Priority Date: 04/13/2012
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Mukai, Tsuyoshi, Dokai, Yuya
• Primary Examiner(s): Wu, Zhen Y
• Application Number:
  US14/266,973
• Publication Number:
  US 20140232532A1
• Time in Patent Office: 1,783 Days
• Field of Search: 340 101, 340 104
• CPC Class Codes: G06K 7/10019 resolving collision on the communication channels between simultaneously or concurrently interrogated record carriers. collision between the communication channels used by wireless communication devices, where the solution is not particularly adapted for RFIDs or the like, H04W74/08
• CPC Class Codes: G06K 7/10366 the interrogation device being adapted for miscellaneous applications
• CPC Class Codes: G06K 7/10465 the interrogation device being capable of self-diagnosis, e.g. in addition to or as part of the actual interrogation process testing of electrical circuits in general G01R31/28

Abstract

An RFID tag inspection method includes the steps of transmitting a measurement signal from a reader/writer simultaneously to a plurality of RFID tags arrayed on a collective base member and configured to process radio signals, receiving response waves from the individual RFID tags in a batch by the reader/writer, and determining, based on strengths and a number of received signals read by the reader/writer, whether or not the individual RFID tags are acceptable. Thus, acceptance/rejection inspection can be performed on the plural RFID tags, which are arrayed on the collective base member, in a batch.

Claims

1. A radio frequency identifier (RFID) tag inspection method comprising the steps of:

transmitting a measurement signal simultaneously to a set including a plurality of RFID tags;

reading responses from each of the plurality of RFID tags in a batch by a reader/writer; and

determining, based on received signal strength indications of the responses read by the reader/writer and a total number of the responses read by the reader/writer, whether or not all of the plurality of RFID tags are acceptable;

wherein

each of the plurality of RFID tags includes a radiation plate having long sides, and the plurality of RFID tags are arranged in a direction perpendicular to the long sides of the radiation plates;

in the transmitting step, the plurality of RFID tags are disposed on a dielectric pedestal;

the dielectric pedestal is disposed between the plurality of RFID tags and the reader/writer; and

the dielectric pedestal shifts a peak frequency with respect to a communication distance between the plurality of the RFID tags and the antenna of the reader/writer.

2. The RFID tag inspection method according to claim 1, wherein the measurement signal is transmitted from the reader/writer.

3. The RFID tag inspection method according to claim 2, wherein, in the reading step, the responses from the RFID tags are intensified by a reflecting plate.

4. The RFID tag inspection method according to claim 1, wherein the measurement signal is transmitted from another reader/writer.

5. The RFID tag inspection method according to claim 1, wherein the determining step includes a step of determining whether signal strengths of the responses from each of the plurality of individual RFID tags are not less than a threshold, and a step of determining whether the total number of the responses is matched with the number of the RFID tags.

10. The RFID tag inspection method according to claim 1, wherein in the reading step, the responses read by the reader/writer are read through the dielectric pedestal.

12. The RFID tag inspection method according to claim 1, wherein the plurality of RFID tags are used in an ultra high frequency (UHF) band RFID system.

6. A radio frequency identifier (RFID) tag inspection device comprising:

a transmitting portion configured to transmit a measurement signal simultaneously to a set including a plurality of RFID tags;

a reading portion configured to read responses from each of the plurality of RFID tags in a batch by a reader/writer; and

a determining portion configured to determine, based on received signal strength indications of the responses read by the reader/writer and a total number of the responses read by the reader/writer, whether or not all of the plurality of RFID tags in the set are acceptable;

wherein

each of the plurality of RFID tags includes a radiation plate having long sides, and the plurality of RFID tags are arranged in a direction perpendicular to the long sides of the radiation plates;

the plurality of RFID tags are disposed on a dielectric pedestal;

the dielectric pedestal is disposed between the plurality of RFID tags and the reader/writer; and

the dielectric pedestal shifts a peak frequency with respect to a communication distance between the plurality of the RFID tags and the antenna of the reader/writer.

7. The RFID tag inspection device according to claim 6, further comprising a reflecting plate disposed at an opposite location to the plurality of RFID tags relative to the reader/writer.

8. The RFID tag inspection device according to claim 7, further comprising an adjusting member arranged to adjust a distance between the reader/writer and the reflecting plate.

9. The RFID tag inspection device according to claim 6, further comprising another reader/writer for transmission, which is disposed at an opposite location to the plurality of RFID tag relative to the reader/writer.

11. The RFID tag inspection device according to claim 6, wherein the reader/writer is configured to read the responses from each of the plurality of RFID tags through the dielectric pedestal.

13. The RFID tag inspection device according to claim 6, wherein the plurality of RFID tags are used in an ultra high frequency (UHF) band RFID system.