Article identification and tracking using electronic shadows created by RFID tags

• US 7,081,818 B2
• Filed: 05/17/2004
• Issued: 07/25/2006
• Est. Priority Date: 05/19/2003
• Status: Expired due to Fees

• Current Assignee: CHECKPOINT SYSTEMS, INC. (CCL Industries Incorporated)
• Original Assignee: CHECKPOINT SYSTEMS, INC. (CCL Industries Incorporated)
• Inventors: Eckstein, Eric, Richie, William S. Jr., Mazoki, Gary T.
• Primary Examiner(s): NGUYEN, HUNG T
• Application Number:
  US10/847,129
• Publication Number:
  US 20050012613A1
• Time in Patent Office: 799 Days
• Field of Search: 340/572.1, 340/572.4, 340/539.1, 340/539.13, 340/568.1, 340/825.49, 340/825.69, 340/10.1, 340/521, 340/522, 340/10.4, 340/10.41
• US Class Current: 340/572.1
• 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 7/10079 the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G07C 9/28 the pass enabling tracking or indicating presence
• CPC Class Codes: G08B 13/2462 Asset location systems combined with EAS inventory, tracking, logistic G06Q10/00; entrance control systems G07C9/00

Abstract

A tracking system uses RFID (radio frequency identification) tag technology to facilitate the identification and tracking of items in an environment through a technique known as shadowing. As an object or target moves within a pre-described detection zone with communicating antenna and RFID sensors, the object or target blocks the line of sight between respective antenna and sensors, preventing electromagnetic coupling between the sensor and the antenna and thus casting an electromagnetic shadow along the line of sight. One approach of this invention uses this shadow technique to perform functions such as theft (shrink) deterrence/detection; tracking the motion of objects through an environment by monitoring the shadow; and correlation analysis of people shadows to tagged items (e.g., merchandise, articles) to foster marketing and merchandizing effectiveness.

Claims

1. A tracking system, comprising:

an identification sensor positioned at a first location, said identification sensor having a responsive circuit;

an antenna positioned at a second location to detect said identification sensor by interactive coupling between said antenna and said identification sensor via communication signals therebetween; and

a processing member that determines an absence of detection of said identification sensor by said antenna, interprets the absence of detection as indicia of an electronic shadow between the first location and the second location, and infers a presence of an object as cause for the electronic shadow.

2. The tracking system of claim 1, further comprising a plurality of identification sensors, each of said plurality of identification sensors positioned at a respective location for detection by interactive coupling between each sensor and said antenna, wherein said processing member further determines an absence of detection of at least one of said plurality of identification sensors by said antenna, interprets the absence of detection as indicia of an electronic shadow between said antenna and said at least one of said plurality of identification sensors, and infers the presence of at least one object as cause for the electronic shadow.

3. The tracking system of claim 2, wherein said antenna periodically detects said plurality of identification sensors by repeated interactive coupling between said antenna and said identification sensors, and said processing member tracks movement of the object by monitoring movement of the electronic shadow.

4. The tracking system of claim 2, wherein each of said plurality of identification sensors is fixed.

5. The tracking system of claim 4, wherein said antenna detects a mobile identification tag adjacent the electronic shadow by interactive coupling between said antenna and the mobile identification tag, said processing member associating the mobile identification tag with the electronic shadow.

6. The tracking system of claim 5, wherein said processing member tracks movement of the mobile identification tag by monitoring movement of the associated electronic shadow.

7. The tracking system of claim 4, wherein said antenna further detects a mobile identification tag attached to a product by interactive coupling between said antenna and the mobile identification tag, said processing member associating the product with the electronic shadow.

8. The tracking system of claim 7, wherein said processing member tracks movement of the product by monitoring movement of the electronic shadow.

9. The tracking system of claim 7, wherein said processing member associates the product with a complimentary product related to the product, and further comprising a display device in communication with said processing member for advertising the complimentary product.

10. The tracking system of claim 1, further comprising a plurality of antennas, each of said plurality of antennas positioned at a respective fixed location for detecting said identification sensor by interactive coupling between said antennas and said identification sensor via communication signals therebetween, wherein said processing member determines an absence of detection of said identification sensor by at least one of said plurality of antennas, interprets the absence of detection as indicia of an electronic shadow between said identification sensor and said at least one of said plurality of antennas, and estimates a size of the object based on a detection or absence of detection of said identification sensor by said plurality of antennas.

11. The tracking system of claim 1, further comprising a plurality of identification sensors and a plurality of antennas, each of said plurality of identification sensors positioned at a respective fixed portion of the first location, each of said plurality of antennas positioned at a respective fixed portion of the second location for detecting at least one of said plurality of identification sensors by interactive coupling between said plurality of antennas and said plurality of identification sensor via communication signals therebetween, wherein said processing member determines an absence of detection of any of said plurality of identification sensors by at least one of said plurality of antennas, and interpret the absence of detection of said identification sensors as indicia of an electronic shadow between said identification sensors and said at least one of said antennas.

12. The tracking system of claim 11, wherein said processing member estimates a size of a footprint of the object as less than a size of the electronic shadow.

13. The tracking system of claim 1, wherein said processing member includes a computer.

14. The tracking system of claim 1, wherein said processing member includes a computer program.

15. The tracking system of claim 1, wherein the first location is in a floor and the second location is in a ceiling.

16. The tracking system of claim 1, wherein said identification sensor is an RFID sensor and said responsive circuit is a resonant rf circuit.

28. The tracking system of claim 1, wherein the object is unknown to said tracking system.

17. A tracking system, comprising:

means for communicating signals along a line of sight between a first location and a second location;

means for detecting the communicated signals at the second location;

means for determining an absence of detection of one of the communicated signals at the second location;

means for interpreting the absence of detection as indicia of a shadow between the first location and the second location; and

means for inferring a presence of an object as cause for the shadow.

18. The tracking system of claim 17, further comprising means for estimating a size of the object.

19. The tracking system of claim 17, further comprising means for monitoring movement of the shadow to track the object.

20. The tracking system of claim 17, further comprising means for detecting an identification tag, and means for associating the identification tag with the shadow.

21. The tracking system of claim 17, further comprising means for detecting an identification tag, means for associating the identification tag with a product, means for associating the product with a complimentary product related to the product, and means for advertising the complimentary product.

29. The tracking system of claim 17, wherein the object is unknown to said tracking system.

22. A method for targeting an object, comprising:

communicating signals along a line of sight between a first location and a second location;

detecting the communicated signals at the second location;

determining an absence of detection of one of the communicated signals at the second location;

interpreting the absence of detection as indicia of a shadow between the first location and the second location; and

inferring a presence of the object as cause for the shadow.

23. The method of claim 22, further comprising estimating a size of the object.

24. The method of claim 22, further comprising monitoring movement of the shadow to track the object.

25. The method of claim 24, further comprising sending an alarm based on the movement of the shadow.

26. The method of claim 22, further comprising detecting an identification tag, and associating the identification tag with the shadow.

27. The method of claim 22, further comprising detecting an identification tag, associating the identification tag with a product, associating the product with a complimentary product related to the product, and advertising the complimentary product.

30. The method of claim 22, wherein the inferring step infers a presence of the object that is an unknown object as cause for the shadow.