Wireless IC device and method of detecting environmental state using the device

• US 8,680,971 B2
• Filed: 03/16/2012
• Issued: 03/25/2014
• Est. Priority Date: 09/28/2009
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Ito, Yuki
• Primary Examiner(s): BEE, ANDREW W.
• Application Number:
  US13/421,889
• Publication Number:
  US 20120176223A1
• Time in Patent Office: 739 Days
• Field of Search: 340/500, 340/531, 340/539.1, 340/539.26, 340/539.27, 340/539.28, 340/540, 340/601, 340/602, 340/657, 340/10.1, 340/10.4
• US Class Current: 340/10.4
• CPC Class Codes: G01K 1/024 for remote indication
• CPC Class Codes: G06K 19/0717 the sensor being capable of sensing environmental conditions such as temperature history or pressure
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/181 Encapsulation
• CPC Class Codes: H01Q 1/2208 associated with components used in interrogation type services, i.e. in systems for information exchange between an interrogator/reader and a tag/transponder, e.g. in Radio Frequency Identification [RFID] systems methods or arrangements for sensing record carriers, e.g. for reading patterns G06K7/00; record carrier for use with machines and with at least a part designed to carry digital markings G06K19/00

Abstract

In a wireless IC device, an insulating material, which has an electrical characteristic that is varied with a change in an environmental state, is provided between a feed circuit board and an antenna to detect the environmental state from a state of a communication characteristic between the wireless IC device and an external reader apparatus.

Claims

1. A wireless IC device comprising:

an RFID IC chip;

a feed circuit board that has the IC chip mounted therein or thereon and that includes a feed circuit connected to the IC chip; and

an antenna coupled to the feed circuit board;

wherein

the wireless IC device communicates with an external reader apparatus via the antenna; and

an insulating material that has an electrical characteristic that varies with a change in an environmental state to vary a coupling state between the feed circuit board and the antenna is provided between the feed circuit board and the antenna such that the environmental state is detected based on a state of a communication characteristic between the wireless IC device and the reader apparatus.

2. The wireless IC device according to claim 1, wherein the environmental state is one of humidity, temperature, and pressure.

3. The wireless IC device according to claim 1, wherein the feed circuit board is electromagnetically coupled to the antenna.

4. The wireless IC device according to claim 1, wherein the communication characteristic is a communicable distance between the wireless IC device and the reader apparatus.

5. A method of detecting an environmental state using a wireless IC device that includes an IC chip, a feed circuit board that has the IC chip mounted therein or thereon and that includes a feed circuit connected to the IC chip, and an antenna coupled to the feed circuit board;

and communicates with an external reader apparatus via the antenna, wherein an insulating material that has an electrical characteristic that varies with a change in an environmental state to vary a coupling state between the feed circuit board and the antenna is provided between the feed circuit board and the antenna to enable detection of the environmental state based on a state of a communication characteristic between the wireless IC device and the reader apparatus.