RF SYSTEMS AND METHODS FOR TRACKING AND SINGULATING TAGGED ITEMS

• US 20080150695A1
• Filed: 03/05/2008
• Published: 06/26/2008
• Est. Priority Date: 06/09/2006
• Status: Active Grant

• Current Assignee: Zest Labs, Inc.
• Original Assignee: Intelleflex Corporation
• Inventors: Batra, Naresh
• Granted Patent: US 7,800,500 B2
• Time in Patent Office: Days
• US Class Current: 340/10.1
• CPC Class Codes: G01S 13/74 Systems using reradiation of radio waves, e.g. secondary radar systems; Analogous systems
• 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

Abstract

A method in one embodiment comprises scanning a zone in an active mode at a first power level for identifying presence of a tag; and scanning portions of the zone in a passive mode at a second power level for again identifying presence of the tag. A system in another embodiment comprises an interrogator for scanning a zone in an active mode at a first power level for identifying presence of a tag; wherein the interrogator also scans portions of the zone for again identifying presence of the tag. A method in another embodiment comprises scanning zones of an area in an active mode for identifying the zone in which the tag is located; and scanning portions of the zone in which the tag is located in a passive mode for identifying the portion of the zone in which the tag is located.

Claims

1. A method, comprising:

scanning a zone in an active mode at a first power level for identifying presence of a tag; and

scanning portions of the zone in a passive mode at a second power level for again identifying presence of the tag.

2. A method as recited in claim 1, further comprising scanning sub-zones of the zone in an active mode at a third power level, the third power level being lower than the first power level.

3. A method as recited in claim 1, further comprising scanning sub-portions of the zone in a passive mode at a fourth power level, the fourth power level being lower than the second power level

4. A method as recited in claim 1, wherein multiple zones are individually scanned.

5. A method as recited in claim 4, wherein a single interrogator is physically moved to each zone.

6. A method as recited in claim 5, wherein a single interrogator performs the scanning in the active mode and the scanning in the passive mode in each of the zones.

7. A method as recited in claim 5, wherein each zone is defined by an effective range of the interrogator at the first power level.

8. A method as recited in claim 4, wherein each zone is scanned by a different interrogator.

9. A method as recited in claim 1, wherein the tag is coupled to an object, the tag storing information about the object.

10. A method as recited in claim 1, wherein the tag is coupled to an object, the tag having a unique identifier, the identifier being correlated with information about the object in a database.

11. A Radio Frequency Identification (RFID) system, comprising:

a plurality of RFID tags; and

an RFID Interrogator in communication with the RFID tags, the RFID interrogator performing at least a portion of the scanning of method 1.

12. A system, comprising:

an interrogator for scanning a zone in an active mode at a first power level for identifying presence of a tag;

wherein the interrogator also scans portions of the zone for again identifying presence of the tag.

13. A system as recited in claim 12, further comprising scanning sub-zones of the zone in an active mode at a third power level, the third power level being lower than the first power level.

14. A system as recited in claim 12, further comprising scanning sub-portions of the zone in a passive mode at a fourth power level, the fourth power level being lower than the second power level

15. A system as recited in claim 12, wherein multiple zones are individually scanned.

16. A system as recited in claim 15, wherein a single interrogator is physically moved to each zone.

17. A system as recited in claim 16, wherein a single interrogator performs the scanning in the active mode and the scanning in the passive mode in each of the zones.

18. A system as recited in claim 16, wherein each zone is defined by an effective range of the interrogator at the first power level.

19. A system as recited in claim 15, wherein each zone is scanned by a different interrogator.

20. A method, comprising:

scanning zones of an area in an active mode for identifying the zone in which the tag is located; and

scanning portions of the zone in which the tag is located in a passive mode for identifying the portion of the zone in which the tag is located.