RFID multiple range method and system

• US 7,489,242 B2
• Filed: 07/13/2005
• Issued: 02/10/2009
• Est. Priority Date: 07/13/2004
• Status: Expired due to Fees

• Current Assignee: MRID UK Limited
• Original Assignee: Mrid Solutions Inc.
• Inventors: Hill, Steven, Lusk, Dennis, Hines, Tony
• Primary Examiner(s): Garber; Charles D.
• Assistant Examiner(s): McNally; Kerri L
• Application Number:
  US11/180,482
• Publication Number:
  US 20060033623A1
• Time in Patent Office: 1,308 Days
• Field of Search: 340/572.1
• US Class Current: 340/572.1
• CPC Class Codes: G08B 21/0227 System arrangements with a plurality of child units
• CPC Class Codes: G08B 21/0275 Electronic Article Surveillance [EAS] tag technology used for parent or child unit, e.g. same transmission technology, magnetic tag, RF tag, RFID
• CPC Class Codes: G08B 21/24 Reminder alarms, e.g. anti-loss alarms

Abstract

The present invention is a method and system for determining the range of an RFID tag from an origin using radio-frequency identification (“RFID”) tags. An RFID tag with a unique numerical identifier is secured to an object. The RFID tag transmits its unique numerical identifier using RF signals, wherein the numerical identifier further comprises an array of extensions. The strength of each of the RF signals corresponds to an extension of the array of extensions. A receiver reads the RF signals and determines the unique numerical identifier and extensions being transmitted. An information processor interconnected with the receiver analyzes the unique numerical identifier and extensions from a predetermined index, and the information processor determines the range of the identity and range of the RFID tag from an origin.

Claims

1. A method for determining the range of an RFID tag from an origin, the method comprising:

securing an RFID tag with a unique numerical identifier to an object wherein the numerical identifier further comprises an array of extensions wherein each extension corresponds to a predetermined spatial range from an origin;

transmitting the unique numerical identifier associated with the RFID tag using RF signals wherein the strength of each of the RF signals corresponds to a particular extension of the array of extensions;

receiving the RF signals at a designated location;

reading the RF signals and determining the extension from a predetermined index being transmitted by the RFID tag and determining the range of the RFID tag from an origin;

reading the RF signals and determining the unique numerical identifier being transmitted by the RFID tag;

analyzing the unique numerical identifier for a corresponding identification of an object from a predetermined index;

determining whether the object was not found on the index; and

alerting a user when an object is missing.

2. The method of claim 1 wherein the RF signals are transmitted intermittently in short predetermined intervals.

3. The method of claim 2 wherein the origin is a transient location of a hand held receiver.

4. The method of claim 2 wherein the origin is a fixed location.

5. The method of claim 1 wherein the RFID tag contains an independent power source.

6. The method of claim 1, and further comprising:

receiving RF signals from a plurality of receivers wherein the receivers are interconnected to an information processor.

7. The method of claim 6, and further comprising:

providing a plurality of information processors wherein each information processor is interconnected to a system wide information processor.

8. A system for determining the range of an RFID tag from an origin, the system comprising:

an RFID tag with a unique numerical identifier secured to an object wherein the numerical identifier further comprises an array of extensions wherein each extension corresponds to a predetermined spatial range from an origin;

a transmitter for transmitting the unique numerical identifier associated with the RFID tag using RF signals wherein the strength of each of the RF signals corresponds to a particular extension of the array of extensions;

a receiver for receiving the RF signals at a designated location; and

an information processor for analyzing the unique numerical identifier being transmitted by the RFID tag and for reading the RF signals to determine the extension from a predetermined index being transmitted by the RFID tag for determining the range of the RFID tag from an origin.

9. The system of claim 8 wherein the RF signals are transmitted intermittently in short predetermined intervals.

10. The system of claim 9 wherein the origin is a transient location of a hand held receiver.

11. The system of claim 9 wherein the origin is a fixed location.

12. The system of claim 8 wherein the RFID tag contains an independent power source.

13. The system of claim 8, and further comprising:

a plurality of receivers interconnected to an information processor for receiving RF signals.

14. The method of claim 13, and further comprising:

a plurality of information processors interconnected to a system wide information processor.