METHOD OF ASSIGNING AND DEDUCING THE LOCATION OF ARTICLES DETECTED BY MULTIPLE RFID ANTENNAE

• US 20130093591A1
• Filed: 11/20/2012
• Published: 04/18/2013
• Est. Priority Date: 01/09/2002
• Status: Active Grant

• Current Assignee: Sensormatic Electronics LLC (Johnson Controls International plc)
• Original Assignee: Sensormatic Electronics LLC (Johnson Controls International plc)
• Inventors: Campero, Richard J., Bauer, Donald G., Rasband, Paul B., Spedden, Richard H., Jones, Matthew A.
• Granted Patent: US 8,730,044 B2
• Time in Patent Office: Days
• 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 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G06K 7/10356 using a plurality of antennas, e.g. configurations including means to resolve interference between the plurality of antennas
• CPC Class Codes: G06Q 10/087 Inventory or stock management, e.g. order filling, procurement or balancing against orders
• CPC Class Codes: G07G 1/0045 with a code reader for reading of an identifying code of the article to be registered, e.g. barcode reader or radio-frequency identity [RFID] reader
• CPC Class Codes: G08B 13/2462 Asset location systems combined with EAS inventory, tracking, logistic G06Q10/00; entrance control systems G07C9/00
• CPC Class Codes: G08B 13/2474 Antenna or antenna activator geometry, arrangement or layout loop antennae H01Q1/22
• CPC Class Codes: H01Q 1/2216 used in interrogator/reader equipment
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop

Abstract

In accordance with preferred embodiments of the invention, a method (and corresponding apparatus) is provided for deducing the location of one or more items or objects to be monitored. In exemplary embodiments, the method (and corresponding apparatus) is implemented in RFID (radio frequency identification) applications (e.g., reading RFID tags at 13.56 MHz and approximately 900 MHz) by deducing the location of an item associated with a unique RFID tag in one or more areas of detection covered by multiple RFID reader antennae.

Claims

1. A method of determining a location of an item, the method comprising:

detecting the presence of an item in an overlapping area of a first detection zone and a second detection zone, the first detection zone associated with a first detector, the second detection zone associated with a second detector;

assigning a first percentage of the item to the first detection zone; and

assigning a second percentage of the item to the second detection zone.

2. The method of claim 1, further comprising adjusting a size of the overlapping area by changing power supplied to at least one of the first and second detectors.

3. The method of claim 2, further comprising associating the item with an RFID tag detectable by the first and second detectors.

4. The method of claim 3, further comprising assigning a unique identification number to the RFID tag, wherein the unique identification number is selected from the group consisting of a manufacturer number, a stock keeping unit number, and a serial number.

5. A system for reading a plurality of items having RFID tags, the system comprising:

a plurality of RFID readers; and

at least first and second RFID reader antennas coupled to the plurality of RFID readers, the at least first and second RFID reader antennas for detecting RFID tags associated with a plurality of items;

wherein a location of the plurality of items is assigned according to a proportion of RFID tags detected by the first RFID reader antenna compared to a proportion of the RFID tags detected by the at least second RFID reader antenna.

6. The system of claim 5, wherein the location of the plurality of items detected by both the first RFID reader antenna and the at least second RFID reader antenna is determined to be in proximity to the first RFID reader antenna and the at least second RFID reader antenna.

7. The system of claim 6, wherein the location of items detected by both the first RFID reader antenna and the at least second RFID reader antenna is determined to be in between the first RFID reader antenna and the at least second RFID reader antenna.

8. A system for determining the location of a plurality of items having RFID tags, the system comprising:

a plurality of RFID reader antennas, each RFID reader antenna having a detection zone, wherein the detection zone of a first one of said plurality of RFID reader antennas overlaps the detection zone of a second one of said plurality of RFID reader antenna; and

at least one RFID reader coupled to the plurality of RFID reader antennas for detecting an item when the presence of the item is detected by both the first and second RFID reader antennas, wherein the at least one RFID reader assigns a first percentage of the item to the first detection zone and assigns a second percentage of the item to the second detection zone.

9. The system of claim 8, wherein the RFID reader is configured to adjust a size of the overlapping area by changing power supplied to at least one of the first and second RFID reader antennas.

10. The system of claim 8, wherein the location of items detected by both the first RFID reader antenna and the at least second RFID reader antenna is determinable to be in between the first RFID reader antenna and the at least second RFID reader antenna

11. A system for reading items having RFID tags, each RFID tag having a unique identification number, the system comprising:

a plurality of RFID reader antennas for reading the RFID tags wherein the RFID reader antennas have a first detection zone and at least a second detection zone;

at least one RFID reader for reading data from the RFID tags within the first detection zone and the at least second detection zone; and

a controller for activating the plurality of RFID reader antennas to read the RFID tags, determining the location of items, and storing data in a local database;

wherein the location of an item is determined to be in the first detection zone when said at least one RFID reader detects the item in at least a predetermined number of read attempts out of a total number of read attempts.

12. The system of claim 11, wherein the location of the items is in the first detection zone or the at least second detection zone.

13. The system of claim 11, wherein the predetermined number of read attempts for which said at least one RFID reader determines that the item is in the first detection zone is 80% of the total number of read attempts made by said at least one RFID reader.

14. A method for determining a location of an item, the method comprising the steps of:

designating first and second detection zones respectively associated with first and second detectors;

detecting the presence of an item when the item is detected by both the first and second detectors;

associating the item with an RFID tag detectable by the first and second detectors;

assigning a unique identification number to the RFID tag, wherein the unique identification number is selected from the group consisting of a manufacturer number, a stock keeping unit number, and a serial number;

detecting the unique identification number during a first read cycle; and

detecting the unique identification number during a second read cycle,

wherein the detection of the unique identification number during the second read cycle is suppressed when the second read cycle is performed less than a predetermined number of read cycles from the first read cycle.

15. The method of claim 14, wherein the first detection zone overlaps at least an area of the second detection zone.

16. The method of claim 15, further comprising adjusting a size of said overlap area by changing power supplied to at least one of the first and second detectors

17. A method of deducing the location of a plurality of items, the method comprising steps of:

providing a plurality of items wherein each item is associated with an RFID tag;

designating first and second detection zones respectively associated with first and second RFID reader antennae;

identifying the items in the first detection zone and the second detection zone with the first and second RFID reader antennae, respectively;

reading the information in the RFID tags;

determining the similarity of the items detected in the first detection zone and the second detection zone according to information in the RFID tags; and

assigning the location of the plurality of items according to the similarity of the items detected in the first detection zone and the second detection zone.

18. The method of claim 17, wherein the information in the RFID tags is selected from the list consisting of an SKU number and a UPC code.

19. The method of claim 17, wherein the similarity of the items is determined by the plurality of items have an identical SKU number or an identical UPC code.

20. The method of claim 17, wherein assigning the location of the plurality of items comprises assigning the plurality of items to at least one of the first and second detection zones.