Location virtualization in an RFID system

• US 20060170565A1
• Filed: 07/29/2005
• Published: 08/03/2006
• Est. Priority Date: 07/30/2004
• Status: Active Grant

• Current Assignee: Quake Global, Inc.
• Original Assignee: Reva Systems Corp. (Quake Global, Inc.)
• Inventors: Fischer, Jeffrey H., Husak, David J., Krishna, Pattabhiraman, Spreadborough, Peter
• Granted Patent: US 7,667,575 B2
• Time in Patent Office: Days
• US Class Current: 340/825.490
• CPC Class Codes: G01S 5/02525 Gathering the radio frequency fingerprints
• CPC Class Codes: G01S 5/06 Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements G01S5/12 takes precedence
• CPC Class Codes: G06K 17/0029 the arrangement being specially adapted for wireless interrogation of grouped or bundled articles tagged with wireless record carriers
• 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 7/10356 using a plurality of antennas, e.g. configurations including means to resolve interference between the plurality of antennas

Abstract

A system and method of determining locations of one or more RFID tags within an RFID environment. The system includes a plurality of RFID readers, each operative to transmit and receive RF signals for scanning a tag disposed within an RF coverage region associated with the reader, and for receiving tag data in response to the scanning of the tag. A plurality of sub-locations is determined within the environment, each corresponding to at least a portion of at least one of a plurality of RF coverage regions associated with the readers. The sub-locations are mapped to a plurality of predefined locations within the environment. A reader scans a tag, and receives tag scan data from the tag in response to the scanning of the tag. The tag scan data includes a tag identifier associated with the scanned tag. The tag scan data is mapped to the sub-locations based on the RF coverage region associated with the reader. The location of the scanned tag is then determined with reference to the predefined locations within the environment, based on the tag identifier included in the tag scan data, the mapping of the tag scan data to the sub-locations, and the mapping of the sub-locations to the predefined locations.

Claims

1. A method of operating a radio frequency identification (RFID) system having at least one RFID tag for providing RFID tag data and at least one RF receiver for receiving RF signals containing said RFID tag data, said method comprising the steps of:

determining a plurality of sub-locations within an environment in which said at least one RF receiver and said at least one RFID tag are located, each sub-location corresponding to at least a portion of at least one of a plurality of RF coverage regions, each coverage region corresponding to an area within which RFID tag data can be received by said at least one RF receiver;

mapping the plurality of sub-locations to a plurality of predefined locations within said environment;

receiving, at one of said at least one RF receiver, RFID tag data from one of said at least one RFID tag;

mapping the RFID tag data to at least one of the sub-locations based on the RF coverage region associated with said at least one RF receiver that received said RFID tag data from said one of said at least one RFID tag; and

determining the location of said one of said at least one RFID tag with reference to the predefined locations within the environment based on the mapping of said RFID tag data to the sub-locations, and the mapping of the sub-locations to the predefined locations.