Systems and methods of locating raido frequency identification tags by radio frequencey technology

• US 20080204200A1
• Filed: 02/26/2007
• Published: 08/28/2008
• Est. Priority Date: 02/26/2007
• Status: Abandoned Application

• Current Assignee: Huicai Zhong, Huilong Zhu
• Original Assignee: Huicai Zhong, Huilong Zhu
• Inventors: Zhu, Huilong, Zhong, Huicai
• Application Number:
  US11/710,673
• Publication Number:
  US 20080204200A1
• Time in Patent Office: Days
• US Class Current: 340/10.3
• CPC Class Codes: G01S 13/878 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S13/874 takes precedence

Abstract

Methods and systems with one or more mobile transceivers to locate position of radio frequency identification (RFID) tags via radio frequency (RF) technology are disclosed. The systems called RF Locator (RFL) include at least one mobile RF transceiver and other functional components such as, a globe positioning system (GPS), a processor, and a display. Information of space positions, times and physical characteristics related to RF signals are collected sequentially by the mobile transceiver(s) during RFID tag locating process. The processor calculates the location of the RFID tag by using the collected information. Two methods to determine the location of the RFID tag are disclosed in this invention. The first method is to utilize the information of space positions and times. The second method is to use the information of space positions and RF signal characteristics.

Claims

1. ) A system for locating an object having an RFID tag, the system comprising:

At least a mobile RF transceiver, the mobile RF transceiver transmitting at several locations and times a plurality of transmitted interrogation RF signals to activate the RFID tag, the mobile RF transceiver at several locations and times receiving a plurality of RFID signals broadcasted from the RFID tag activated by the interrogation RF signals and measuring the strength and/or frequency of a plurality of RFID signals broadcasted from the RFID tag activated by the interrogation RF signal;

at least a positioning device, the positioning device determining the locations where the mobile RF transceiver transmitting a plurality of transmitted interrogation RF signals to activate the RFID tag and receiving a plurality of RF signals broadcasted from the RFID tag activated by the interrogation RF signals;

at least a clock, the clock determining the times when the mobile RF transceiver transmits a plurality of transmitted interrogation RF signals to activate the RFID tag and receives a plurality of RF signals broadcasted from the RFID tag activated by the interrogation RF signals;

at least a processor, the processor saving the locations, the times, the strengths of the RF signals, and the frequencies of the RF signals, the processor calculating the location of the RFID tag;

at least an input device, the input device feeding data into the processor; and

at least an output device, the output device representing data including, but not limited to, the location of the RFID tag.

2. ) The system of claim 1, wherein said mobile RF transceiver consists of at least one RF transmitter and at least one RF receiver.

3. ) The system of claim 1, wherein said positioning device is a global positioning system (GPS), a spatial measuring device, and combination therein.

4. ) The system of claim 1, wherein said clock is atomic clock.

5. ) The system of claim 1, wherein said processor consists of logic and memory units.

6. ) The system of claim 1, wherein said input is a keyboard, a voice recognition device, and combination therein.

7. ) The system of claim 1, wherein said output device is a display, a speaker, an audible instruction device, and combination therein.

8. ) The system of claim 1, wherein said positioning device is integrated to said mobile RF transceiver.

9. ) The system of claim 1, wherein said clock is integrated to said mobile RF transceiver.

10. ) The system of claim 1, wherein said processor is integrated to said mobile RF transceiver.

11. ) The system of claim 1, wherein said input device is integrated to said mobile RF transceiver.

12. ) The system of claim 1, wherein said output device is integrated to said mobile RF transceiver.

13. ) A method for locating an object having an RFID tag, the method comprising:

An mobile RF transceiver transmitting in at least two locations and at least two times a plurality of transmitted interrogation RF signals to activate the RFID tag, the mobile RF transceiver in at least two locations and at least two times receiving a plurality of RFID signals broadcasted from the RFID tag activated by the interrogation RF signals, the mobile RF transceiver measuring RF physical characteristics of the interrogation RF signals and the RFID signals broadcasted from the RFID tag activated by the interrogation RF signals;

a positioning device determining the locations where the mobile RF transceiver transmits a plurality of transmitted interrogation RF signals to activate the RFID tag and receives a plurality of RF signals broadcasted from the RFID tag activated by the interrogation RF signal;

a clock determining the times when the mobile RF transceiver transmits a plurality of transmitted interrogation RF signals to activate the RFID tag and receives a plurality of RFID signals broadcasted from the RFID tag activated by the interrogation RF signal;

a processor saving the locations, the times, RF signal physical characteristics, the processor calculating the location of the RFID tag;

an input device feeding the information of RFID tag into the processor; and

an output representing the locations and the times.

14. ) The method of claim 13, wherein said processor is a processing component that can be used to save said locations, said times, save said RF physical characteristics of interrogation RF signals and RFID signals, and to determine RFID tag locations with the saved said locations, said times, said physical characteristics of interrogation RF signal and physical characteristics of RFID signals.

15. ) The method of claim 13, wherein said RF physical characteristics of interrogation RF signals and RFID signals are the strengths of said interrogation RF and said RFID signals, and said interrogation frequencies of the RF and said RFID signals.

16. ) The method of claim 13, wherein said RFID tag is a passive electric component that transmits a RF signal containing stored identification when the RFID tag gets activated by an interrogation RF signal.

17. ) The method of claim 13, wherein said physical characteristics are Doppler shift of the wavelength and/or frequency of interrogation RF and said RFID signals.

18. ) The method of claim 13, wherein said time could be determined by an atomic clock.

19. ) The method of claim 13, wherein said location could be determined by a global positioning system at where said mobile RF transceiver either transmits said interrogation RF signal or receives said RFID signals broadcasted from the RFID tag activated by said interrogation RF signals.

20. ) The method of claim 19, wherein said RFID signal is a RF signal transmitted by a RFID tag when the RFID tag gets activated by an interrogation RF signal.