RFID material tracking method and apparatus

• US 8,125,316 B2
• Filed: 08/28/2002
• Issued: 02/28/2012
• Est. Priority Date: 08/09/1999
• Status: Expired due to Fees

• Current Assignee: Round Rock Research LLC
• Original Assignee: Round Rock Research LLC
• Inventors: Moore, Scott E.
• Primary Examiner(s): Nguyen, Nam V
• Application Number:
  US10/229,440
• Publication Number:
  US 20020190845A1
• Time in Patent Office: 3,471 Days
• Field of Search: 340/825.54, 340/835.49, 340/572.1, 340/568.1, 340/539, 340 101- 105, 705/28, 235/385, 235/375, 379/106.2, 379/106.11
• US Class Current: 340/10.4
• CPC Class Codes: G06K 17/00 Methods or arrangements for effecting co-operative working between equipments covered by two or more of main groups G06K1/00 - G06K15/00, e.g. automatic card files incorporating conveying and reading operations
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G08B 13/2462 Asset location systems combined with EAS inventory, tracking, logistic G06Q10/00; entrance control systems G07C9/00

Abstract

A method and apparatus for tracking items automatically is described. A passive RFID (Radio Frequency IDentification) tag is used with a material tracking system capable of real-time pinpoint location and identification of thousands of items in production and storage areas. Passive RFID tags are attached to the item to be tracked, remote sensing antennas are placed at each remote location to be monitored, interrogators with several antenna inputs are connected to the sensing antennas to multiplex the antenna signals, and a host computer communicates with the interrogators to determine item locations to an exacting measure.

Claims

1. A system for tracking an object, the system comprising:

a first radio frequency identification (RFID) tag attached to the object;

a central database;

a database server communicatively coupled to the central database;

a plurality of sensing antennas each provided with a location identifier, wherein the plurality of sensing antennas comprises a first sensing antenna that is provided with a first location identifier, the first sensing antenna being the sensing antenna that is positioned closest to the first RFID tag relative to the other sensing antennas;

an antenna map comprising an address corresponding to each of the plurality of sensing antennas, wherein the antenna map is accessed to determine which sensing antennas are active, the antenna map comprising an address for each sensing antenna; and

a plurality of interrogators positioned remotely from one another, each of the plurality of interrogators having at least one interrogating antenna coupled to at least some of the active sensing antennas, each of the plurality of interrogators being communicatively coupled to the database server and configured to interrogate RFID tags using the at least some of the active sensing antennas including the first sensing antenna and to use the at least one interrogating antenna to receive identifying information from the interrogated RFID tags, at least one interrogator of the plurality of interrogators being configured to update the central database via the database server with positional information identifying a current location of the first RFID tag identified by the interrogator via the first sensing antenna;

wherein the current location of the first RFID tag is identified based on the first location identifier of the first sensing antenna.

2. The system of claim 1, wherein the central database is further configured to provide reports for timing of one or more processes, or timing of a transfer from a first point to a second point.

3. The system of claim 1, further comprising a management system communicatively coupled to the database server to access the central database to provide one or more reports regarding a flow of product through a system.

4. The system of claim 1, further comprising a management system communicatively coupled to the database server to provide a notification of arrival or departure.

5. The system of claim 1, further comprising a management system communicatively coupled to the database server to create a history report of one or more objects.

6. The system of claim 1, further comprising a management system communicatively coupled to the database server to generate a spare inventory report.

7. The system of claim 1, wherein each of the plurality of interrogators is configured to interrogate in a plurality of areas separately.

8. The system of claim 7, wherein the plurality of sensing antennas is respectively located in the plurality of areas such that each sensing antenna interrogates a corresponding area.

9. The system of claim 7, wherein the plurality of sensing antennas is respectively located in the plurality of areas such that each interrogator is configured to excite the sensing antennas one at a time to interrogate the plurality of areas.

10. The system of claim 1, wherein each of the plurality of interrogators is configured to excite at least one sensing antenna to power the RFID tag to provide the identifying information via the sensing antenna if the RFID tag is in vicinity of the sensing antenna.

11. The system of claim 10, wherein each sensing antenna has a tuned tank circuit collocated with the sensing antenna.

12. The system of claim 1, wherein the positional information uniquely identifies the current location of the RFID tag among locations of a plurality of RFID tags attached to a plurality of objects in vicinity of the tracked object.

13. A system for tracking an object, the system comprising:

a central database, the central database being configured to be accessible from a multitude of locations and store information associated with a plurality of radio frequency identification (RFID) tags and objects to which each of the plurality of RFID tags is attached;

a plurality of sensing antennas in communication with the RFID tags, wherein each sensing antenna is provided with a location identifier;

an antenna map comprising an address corresponding to each of the plurality of sensing antennas, wherein the antenna map is accessed to determine which sensing antennas are active, the antenna map comprising an address for each sensing antenna; and

a plurality of readers configured to communicatively couple to the central database and the sensing antennas, wherein each reader is configured to interrogate the plurality of RFID tags using the active sensing antennas to obtain identifying information, the plurality of readers each being further configured to update the central database with a current location of each RFID tag, wherein the current location of each RFID tag is identified based on the location identifier of the active sensing antenna that is positioned closest to the corresponding RFID tag relative to the other sensing antennas.

14. The system of claim 13, wherein the central database is further configured to provide reports for one or more of a length of time spent in one or more processes, and time spent being transferred between a plurality of locations.

15. The system of claim 13, further comprising an inventory system communicatively coupled to the central database, the inventory system configured to track a product through a system.

16. The system of claim 13, further comprising an inventory system communicatively coupled to the central database, the inventory system configured to provide a notification of arrival or departure of one or more objects associated with one or more of the RFID tags.

17. The system of claim 13, further comprising an inventory system communicatively coupled to the central database, the inventory system configured to generate one or more history reports of one or more objects associated with one or more of the RFID tags.

18. The system of claim 13, further comprising an inventory system communicatively coupled to the central database, the inventory system being configured to generate a spare inventory report.

19. The system of claim 13, wherein the plurality of readers is connected to the plurality of sensing antennas to interrogate at a plurality of locations.

20. The system of claim 19, wherein the location identifier of the respective sensing antenna is independent from a port of the reader to which the respective sensing antenna is attached.

21. The system of claim 20, wherein the respective sensing antenna is attached to the port of the reader via cable and jack.

22. The system of claim 19, wherein the respective sensing antenna is not collocated with the reader to which the respective sensing antenna is attached.

23. A system to track objects, the system comprising:

a database configured to be accessible from a multitude of locations, the database configured to store information associated with a plurality of radio frequency identification (RFID) tags and objects to which the plurality of RFID tags are attached;

a plurality of sensing antennas in communication with the RFID tags, wherein each sensing antenna is provided with a location identifier;

an antenna map comprising an address corresponding to each of the plurality of sensing antennas, wherein the antenna map is accessed to determine which sensing antennas are active, the antenna map comprising an address for each sensing antenna; and

an interrogator communicatively coupled to the database, wherein the interrogator is connected to the plurality of sensing antennas positioned at various locations remote to the interrogator to interrogate the RFID tags at the various locations using the active sensing antennas, the interrogator being configured to update the database with status information regarding the RFID tags, wherein the status information is determined for each RFID tag based on the location identifier of the active sensing antenna that is positioned closest to the corresponding RFID tag relative to the other sensing antennas.

24. The system of claim 23, wherein the status information comprises real time locations of the objects.

25. The system of claim 24, wherein the interrogator is configured to excite the sensing antennas one at a time to interrogate the RFID tags at the various locations.

26. The system of claim 24, further comprising a display device to provide a graphic display of the real time locations of the objects.

27. The system of claim 23, wherein the status information comprises indications of whether or not the objects are stored at the various locations.

28. A method to track objects, the method comprising:

providing a database to store information associated with a plurality of radio frequency identification (RFID) tags and objects to which the plurality of RFID tags are attached;

coupling a plurality of sensing antennas to be in communication with the plurality of RFID tags, wherein each sensing antenna is provided with a location identifier;

accessing an antenna map to determine which sensing antennas are active, wherein the antenna map comprises an address corresponding to each of the plurality of sensing antennas; and

connecting an interrogator to the plurality of sensing antennas positioned at various locations remote to the interrogator to interrogate the RFID tags at the various locations using the active sensing antennas, wherein the interrogator is communicatively coupled to the database to update the database with status information regarding the RFID tags, wherein the status information is determined for each RFID tag based on the location identifier of the active sensing antenna that is positioned closest to the corresponding RFID tag relative to the other sensing antennas.

29. The method of claim 28, wherein the connecting of the interrogator to the plurality sensing antennas comprises connecting the interrogator to the sensing antennas via cable and jack.

30. The method of claim 28, wherein each of the sensing antennas has a collocated antenna circuit.

31. The method of claim 30, wherein the antenna circuit comprises a tuned tank circuit.