Radio frequency identification sensor assembly

• US 9,317,726 B2
• Filed: 03/14/2013
• Issued: 04/19/2016
• Est. Priority Date: 04/23/2012
• Status: Active Grant

• Current Assignee: Avery Dennison Retail Information Services LLC (Avery Dennison Corporation)
• Original Assignee: Avery Dennison Corporation
• Inventors: Forster, Ian J.
• Primary Examiner(s): McNally, Kerri
• Application Number:
  US13/803,397
• Publication Number:
  US 20130278387A1
• Time in Patent Office: 1,132 Days
• Field of Search: 340 101- 106, 3405721-5729, 235375-385
• US Class Current: 1/1
• CPC Class Codes: G06K 19/0717 the sensor being capable of sensing environmental conditions such as temperature history or pressure
• CPC Class Codes: G06K 7/10366 the interrogation device being adapted for miscellaneous applications

Abstract

In accordance with one embodiment, an RFID sensor assembly comprises a sensing RFID chip and a reference RFID chip. The sensing RFID chip and the reference RFID chip are configured for electrical coupling to an electronic component via a coupling arrangement. The coupling arrangement of the sensing RFID chip is configured to vary a coupling property in response to a sensed parameter.

Claims

1. An RFID system comprising:

an RFID sensor assembly with at least one pair of RFID chips in which at least one chip of the pair is a sensing RFID chip and at least one chip of the pair is a reference chip; and

an RFID interrogator wherein the interrogator includes an RFID reader and a first antenna such that the reader is configured to vary a power and frequency of a signal transmitted to the at least one pair of RFID chips;

wherein the at least one pair of RFID chips is coupled to a second antenna and the sensor assembly detects any combination of sensed parameters.

2. The system of claim 1, wherein the sensed parameters are a specific or general class of airborne chemicals.

3. The system of claim 1, wherein the at least one pair of RFID chips are electrically coupled to the second antenna by respective coupling capacitors.

4. The system of claim 1, wherein the at least one pair of chips are encoded with a unique identifier.

5. The system of claim 1, wherein the interrogator communicates with the sensor assembly using an inventory scan.

6. The system of claim 1, wherein each RFID chip has a characteristic receive impedance Zr and characteristic backscatter impedance Zb.

7. A method of utilizing a RFID sensor assembly comprising:

providing a RFID sensor assembly having at least one pair of RFID chips, and a RFID interrogator wherein the interrogator includes a RFID reader and a first antenna with the at least one pair of RFID chips coupled to a second antenna such that the reader is configured to vary a power and frequency of a signal transmitted to the at least one pair of RFID chips;

transmitting signals to the RFID sensor assembly via the first antenna;

receiving the signals by the second antenna;

directing those signals to at least one the pair of RFID chips; and

determining a sensed parameter such that at least one RFID chip is configured to vary a coupling property in response to a sensed parameter.

8. The method of claim 7, further comprising sending signals to the first antenna of the RFID interrogator.

9. The method of claim 7, wherein the signals are encoded with a unique identifier.

10. The method of claim 7, wherein the method further comprising interrogating the RFID reader and identifying each RFID chip according to their unique identifier.

11. The method of claim 7, wherein the at least one pair of RFID chips is coupled to a dipole antenna.

12. The method of claim 11, wherein the at least one pair are in electrical communication with first and second links.

13. The method of claim 12, wherein the first and second links are configured such that a conductivity of the links remains constant in response to a sensed parameter.

14. The method of claim 12, wherein the first and second links are forms of a material compound having substantially constant conductivity.

15. The method of claim 7, wherein the at least one pair of RFID chips includes at least one sensing RFID chip.

16. The method of claim 7, wherein the at least one pair of RFID chips includes at least one reference RFID chip.