Radio frequency identification (RFID) tag antenna design

• US 7,800,503 B2
• Filed: 05/11/2007
• Issued: 09/21/2010
• Est. Priority Date: 05/11/2006
• Status: Active Grant

• Current Assignee: Axcess International, Inc. (Amphion Innovations PLC)
• Original Assignee: Axcess International, Inc. (Amphion Innovations PLC)
• Inventors: De Witte, Erik, Bridgelall, Rajinder, Royston, Philip S., Brennan, Paul V.
• Primary Examiner(s): HOFSASS, JEFFERY A
• Application Number:
  US11/747,700
• Publication Number:
  US 20080042850A1
• Time in Patent Office: 1,229 Days
• Field of Search: 340/572.1, 340/0.7, 340/0.8, 340/10.1, 340/539.1
• US Class Current: 340/572.7
• 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 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: G06K 19/07767 the first and second communication means being two different antennas types, e.g. dipole and coil type, or two antennas of the same kind but operating at different frequencies
• CPC Class Codes: H01Q 1/2225 used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H01Q 9/26 with folded element or elements, the folded parts being spaced apart a small fraction of operating wavelength resonant loop antennas H01Q7/00
• CPC Class Codes: H01Q 9/285 Planar dipole H01Q9/065 takes precedence; patch antenna H01Q9/0407

Abstract

In certain embodiments, a hybrid radio frequency identification (RFID) tag includes circuitry, a battery, and a first antenna. The circuitry includes one or more passive RFID elements and one or more semi-active RFID elements operable to transmit and receive communications to and from one or more RFID tag tracking systems. The battery is coupled to the one or more semi-active elements. The first antenna is coupled to the passive RFID elements and to the semi-active RFID elements, the first antenna comprising a shape that defines a first open area and a second open area. The circuitry is positioned within one of the first and second open areas defined by the shape of the first antenna, and the battery is positioned within the other of the first and second open areas defined by the shape of the first antenna.

Claims

1. A hybrid radio frequency identification (RFID) tag, comprising:

circuitry comprising one or more passive RFID elements and one or more semi-active RFID elements operable to transmit and receive communications to and from one or more RFID tag tracking systems;

a battery coupled to the one or more semi-active elements;

a first antenna coupled to the passive RFID elements and to the semi-active RFID elements, the first antenna comprising a shape that defines a first open area and a second open area; and

wherein the circuitry is positioned within one of the first and second open areas defined by the shape of the first antenna and the battery is positioned within the other of the first and second open areas defined by the shape of the first antenna.

2. The RFID tag of claim 1, wherein the shape of the first antenna comprises a substantially S-shape.

3. The RFID tag of claim 1, wherein the shape of the first antenna comprises a substantially W-shape or M-shape.

4. The RFID tag of claim 1, wherein a portion of the first antenna substantially separates on a common plane the first and second open areas defined by the shape of the first antenna.

5. The RFID tag of claim 1, wherein at least a portion of each of the circuitry, the battery, and the first antenna are formed on a common substrate.

6. The RFID tag of claim 1, wherein the first antenna comprises a printed circuit board (PCB) trace.

7. The RFID tag of claim 1, wherein the first antenna comprises an ultra-high frequency (UHF) dipole antenna.

8. The RFID tag of claim 1, wherein the first antenna comprises a single antenna shared between the one or more passive RFID elements and the one or more semi-active RFID elements of the circuitry.

9. The RFID tag of claim 1, wherein the first antenna is operable to communicate within each of the following frequency bands:

315 MHz;

433 MHz; and

860 MHz to 928 MHz.

10. The RFID tag of claim 1, comprising an inductive element coupled to the first antenna and operable to perform a matching function for the RFID tag.

11. The RFID tag of claim 1, comprising a second antenna in one of the first and second open areas of the tag defined by the first antenna, the second antenna comprising an LF antenna.

12. The RFID tag of claim 11, wherein one or more of the following is true:

the second antenna substantially surrounds the circuitry; and

the second antenna substantially surrounds the battery.

13. The RFID tag of claim 11, wherein the second antenna comprises a coil antenna.

14. The RFID tag of claim 1, wherein the battery comprises a battery packaging that comprises a material that is operable to enhance a magnetic field of the first antenna.

15. The RFID tag of claim 1, wherein the battery comprises a battery packaging operable to serve as a counterpoint of a monopole.

16. A method for forming a radio frequency identification (RFID) tag, comprising:

providing circuitry comprising one or more passive RFID elements and one or more semi-active RFID elements operable to transmit and receive communications to and from one or more RFID tag tracking systems;

providing a battery coupled to the one or more semi-active elements;

providing a first antenna coupled to the passive RFID elements and to the semi-active RFID elements, the first antenna comprising a shape that defines a first open area and a second open area; and

wherein the circuitry is positioned within one of the first and second open areas defined by the shape of the first antenna and the battery is positioned within the other of the first and second open areas defined by the shape of the first antenna.

17. The method of claim 16, wherein the shape of the first antenna comprises one or more of the following:

a substantially S-shape; and

a substantially W-shape or M-shape.

18. The method of claim 16, wherein a portion of the first antenna substantially separates on a common plane the first and second open areas defined by the shape of the first antenna.

19. The method of claim 16, comprising providing at least a portion of each of the circuitry, the battery, and the first antenna on a common substrate.

20. The method of claim 16, wherein the first antenna comprises a printed circuit board (PCB) trace.

21. The method of claim 16, wherein the first antenna comprises an ultra-high frequency (UHF) dipole antenna.

22. The method of claim 16, wherein the first antenna comprises a single antenna shared between the one or more passive RFID elements and the one or more semi-active RFID elements of the circuitry.

23. The method of claim 16, wherein the first antenna is operable to communicate within each of the following frequency bands:

315 MHz;

433 MHz; and

860 MHz to 928 MHz.

24. The method of claim 16, comprising providing an inductive element coupled to the first antenna and operable to perform a matching function for the RFID tag.

25. The method of claim 16, comprising providing a second antenna in one of the first and second open areas of the tag defined by the first antenna, the second antenna comprising an LF antenna.

26. The method of claim 25, wherein one or more of the following is true:

the second antenna substantially surrounds the circuitry; and

the second antenna substantially surrounds the battery.

27. The method of claim 25, wherein the second antenna comprises a coil antenna.

28. The method of claim 16, wherein the battery comprises a battery packaging that comprises a material that is operable to enhance a magnetic field of the first antenna.

29. The method of claim 16, wherein the battery comprises a battery packaging operable to serve as a counterpoint of a monopole.

30. A hybrid radio frequency identification (RFID) tag, comprising:

circuitry comprising one or more passive RFID elements and one or more semi-active RFID elements operable to transmit and receive communications to and from one or more RFID tag tracking systems;

a battery coupled to the one or more semi-active elements;

a first antenna coupled to the passive RFID elements and to the semi-active RFID elements, the first antenna comprising one of the following shapes;

a substantially S-shape;

or

a substantially W-shape or M-shape;

wherein;

the shape of the first antenna defines a first open area and a second open area; and

wherein the circuitry is positioned within one of the first and second open areas defined by the shape of the first antenna and the battery is positioned within the other of the first and second open areas defined by the shape of the first antenna, a portion of the first antenna substantially separating on a common plane the first and second open areas defined by the shape of the first antenna;

the RFID tag further comprises a second antenna in one of the first and second open areas defined by the first antenna, the second antenna comprising an LF antenna.

31. The RFID tag of claim 30, wherein at least a portion of each of the circuitry, the battery, and the first antenna are formed on a common substrate.

32. The RFID tag of claim 30, wherein the first antenna comprises an ultra-high frequency (UHF) dipole antenna.

33. The RFID tag of claim 30, wherein the first antenna comprises a single antenna shared between the one or more passive RFID elements and the one or more semi-active RFID elements of the circuitry.

34. The RFID tag of claim 30, wherein the first antenna is operable to communicate within each of the following frequency bands:

315 MHz;

433 MHz; and

860 MHz to 928 MHz.

35. The RFID tag of claim 30, wherein one or more of the following is true:

the second antenna substantially surrounds the circuitry; and

the second antenna substantially surrounds the battery.

36. The RFID tag of claim 30, wherein the second antenna comprises a coil antenna.