Active RFID tag utilizing a secondary communication mode

• US 7,295,108 B2
• Filed: 03/17/2005
• Issued: 11/13/2007
• Est. Priority Date: 03/22/2004
• Status: Expired due to Fees

• Current Assignee: Edgy Communications LLC
• Original Assignee: SYMX Systems Incorporated
• Inventors: Corrado, Anthony P., Logan, Rex
• Primary Examiner(s): MULLEN, THOMAS J
• Application Number:
  US11/082,327
• Publication Number:
  US 20050206503A1
• Time in Patent Office: 971 Days
• Field of Search: 340/572.1, 340/572.4, 340/505, 340/10.1, 340/5.92, 340/539.22, 340/539.26, 340/10.51, 340/10.41, 235/385, 705/28
• US Class Current: 340/539.22
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 19/0724 the arrangement being a circuit for communicating at a plurality of frequencies, e.g. for managing time multiplexed communication over at least two antennas of different types
• CPC Class Codes: G06K 19/0728 the arrangement being an optical or sound-based communication interface
• CPC Class Codes: G06K 19/07345 by activating or deactivating at least a part of the circuit on the record carrier, e.g. ON/OFF switches
• CPC Class Codes: G06K 19/145 at least one of the further markings being adapted for galvanic or wireless sensing, e.g. an RFID tag with both a wireless and an optical interface or memory, or a contact type smart card with ISO 7816 contacts and an optical interface or memory
• CPC Class Codes: G06K 7/10079 the collision being resolved in the spatial domain, e.g. temporary shields for blindfolding the interrogator in specific directions

Abstract

Embodiments of the present invention relate to methods and systems for radio frequency identification. According to one embodiment, a radio frequency identification system comprises a radio frequency identification tag. The tag comprises a radio frequency transmitter and an optical receiver. A reader is communicatively coupled with the tag and is adapted to receive information from the radio frequency identification tag via the radio frequency transmitter of the radio frequency identification tag. The system also includes a trigger communicatively coupled with the tag. The trigger is adapted to send information to the radio frequency identification tag via the optical receiver of the radio frequency identification tag.

Claims

1. A radio frequency identification and autonomous tracking system comprising:

a) an active, dual-mode radio frequency identification tag having a primary and a secondary communication mode, said primary communication mode comprising a radio frequency transmitter and said secondary communication mode comprising an optical receiver;

b) a reader communicatively coupled with and adapted with a radio frequency receiver to receive signals representative of information from the radio frequency identification tag via the radio frequency transmitter of the radio frequency identification tag;

c) a trigger, locally positioned with respect to said tag, communicatively coupled with and adapted with an optical transmitter to send information to the radio frequency identification tag via the secondary mode optical receiver of the radio frequency identification tag; and

d) said tag is configured for local triggering by a secondary mode communication signal from said trigger to cause the tag to transmit information between said tag and said reader via said radio frequency primary communication mode.

2. The radio frequency identification system of claim 1, wherein the radio frequency identification tag further comprises an optical transmitter and the trigger further comprises an optical receiver coupled with and adapted to receive information from the radio frequency identification tag via the optical transmitter of the radio frequency identification tag.

3. The radio frequency identification system of claim 2, wherein the radio frequency identification tag is adapted to transmit signals representing information, data, sensor data, tag identification, trigger identification, and combinations thereof, to the trigger via the optical transmitter in response to receiving a signal from the trigger via the optical receiver.

4. The radio frequency identification system of claim 3 wherein the reader includes an optical receiver, and said radio frequency identification tag is adapted to transmit said signals to the reader via the secondary communication mode optical transmitter in response to receiving a secondary communication mode command from the trigger.

5. The radio frequency identification system of claim 3, wherein the reader includes an optical receiver, and said radio frequency identification tag is adapted to transmit a secondary communication mode periodic beacon to the reader via the optical transmitter of said tag in response to receiving a command from the trigger.

6. The radio frequency identification system of claim 3, wherein the reader includes an optical receiver, and said radio frequency identification tag is adapted to transmit sensor data to the reader via the optical transmitter in response to receiving a command from the trigger.

7. The radio frequency identification system of claim 1, wherein in response to said local triggering, the radio frequency identification tag is adapted to transmit signals representing information, data, sensor data, tag identification, trigger identification, and combinations thereof, to the reader via the radio frequency transmitter the tag in response to receiving a secondary, optical, communication signal from the trigger via the optical receiver of the tag.

8. The radio frequency identification system of claim 7 wherein the radio frequency identification tag is adapted to transmit tag identification information to the reader via the radio frequency transmitter in response to receiving a command from the trigger.

9. The radio frequency identification system of claim 7 wherein the radio frequency identification tag is adapted to transmit a periodic beacon to the reader via the radio frequency transmitter in response to receiving a command from the trigger.

10. The radio frequency identification system of claim 7, wherein the radio frequency identification tag is adapted to transmit sensor data to the reader via the radio frequency transmitter in response to receiving a command from the trigger.

11. An active, dual mode radio frequency identification tag for a radio frequency identification and autonomous tracking system comprising:

a) a primary mode of communication to a reader of said system having a radio frequency receiver, said primary communication mode including a radio frequency transmitter in said tag adapted to transmit information to said radio frequency reader of said system;

b) a secondary mode of communication with a trigger positioned locally with respect to said tag, said secondary communication mode including an optical receiver in said tag adapted to receive information from said optical trigger of said system; and

c) said tag is configured for local triggering by a secondary mode communication signal from said trigger to cause the tag to transmit information between said tag and said reader via said radio frequency primary communication mode.

12. The radio frequency identification tag of claim 11, wherein the radio frequency identification tag further comprises an optical transmitter adapted to send information to at least one of the trigger and the reader of the radio frequency identification system.

13. The radio frequency identification system of claim 12, wherein the radio frequency identification tag is adapted to transmit signals representing information, data, sensor data, tag identification information, trigger identification information, and combinations thereof, to the trigger or the reader via the optical transmitter of the tag in response to receiving a secondary communication mode signal from the trigger via the optical receiver of the tag.

14. The radio frequency identification tag of claim 11, wherein the radio frequency identification tag is adapted to transmit signals representing information, data, sensor data, tag identification information, trigger identification information, and combinations thereof, to the reader via the radio frequency transmitter of the tag in response to receiving a secondary communication mode signal from the trigger via the optical receiver of the tag.

15. The radio frequency identification tag of claim 14, which is adapted to transmit a periodic beacon to the reader via the radio frequency transmitter in response to receiving a command from the trigger.

16. A method of communicating with a radio frequency identification tag in a radio frequency identification and tracking system comprising a plurality of tags, and at least one other, separate device having trigger functionality, the method comprising the steps of:

a) providing an active, bimodal radio frequency tag having a primary, radio frequency, mode of communication and a secondary, optical or ultrasonic, mode of communication;

b) configuring said tag to be triggered by a secondary, optical or ultrasonic, mode of communication signal from said trigger of said radio frequency identification system, to cause said tag to transmit a selected signal via said primary, radio frequency, mode of communication upon receipt by said tag of said secondary mode of communication signal;

c) transmitting a secondary, optical or ultrasonic, mode of communication signal from said trigger, locally positioned with respect to said tag; and

d) receiving said selected signal transmitted from the radio frequency identification tag via said primary, radio frequency, mode of communication in response to the trigger signal.

17. The method of claim 16, wherein said selected signal from said tag is received by a reader, and said selected signal from said tag comprises information, data, sensor data, tag identification information, trigger identification information, and combinations thereof.

18. The method of claim 16, wherein said step of configuring said tag includes causing said tag to transmit signals to a reader, or a trigger via the secondary, optical or ultrasonic, mode of communication.

19. The method of claim 16, wherein said selected signal from the radio frequency identification tag comprises tag identification information and trigger identification information so that said tag can be associated as being within the field of view of said trigger.

20. The method of claim 16, further comprising the steps of:

e) transmitting from said tag, in advance of transmitting information-containing signals, a calibration set of signal pulses to the reader via said primary, radio frequency, mode of communication;

f) measuring the timing of the calibration set of signal pulses to determine an amount of temperature drift in the radio frequency identification tag information-containing signals; and

g) applying the timing of the calibration set of signal pulses to subsequent information-containing signals from the radio frequency identification tag to obtain information from said signals.

21. The method of claim 20, wherein said step of measuring the timing of said calibration set of signal pulses comprises measuring the center of one-half calibration pulse width to establish timing associated with a subsequent pulse train.

22. The method of claim 16, wherein said trigger transmits a command signal to said tag to transmit a periodic beacon to a reader via the primary, radio frequency, mode of communication, so that said tag-transmitted signal permits discrimination of the transmitting tag from among said plurality of tags within said field of view.