Semi-active RFID tag and related processes

• US 8,237,561 B2
• Filed: 07/19/2006
• Issued: 08/07/2012
• Est. Priority Date: 07/19/2005
• Status: Active Grant

• Current Assignee: Precision Dynamics Corporation (Brady Corporation)
• Original Assignee: Precision Dynamics Corporation (Brady Corporation)
• Inventors: Tuttle, John R., Beigel, Michael L.
• Primary Examiner(s): La, Anh V
• Application Number:
  US11/458,459
• Publication Number:
  US 20070018832A1
• Time in Patent Office: 2,211 Days
• Field of Search: 340/573.1, 3405721-5728, 340/10.33, 340/10.1, 340/5.61, 342/30, 342/42, 342/51, 455/73, 455/574, 235/380, 235/487, 235/492
• US Class Current: 340/572.1
• 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 19/0739 the incapacitated circuit being part of an antenna
• CPC Class Codes: G06K 19/07762 the adhering arrangement making the record carrier wearable, e.g. having the form of a ring, watch, glove or bracelet record carriers for insertion in the human body for medical purposes A61B90/00; record carriers adapted for attachment to animals A01K11/00
• CPC Class Codes: G08B 21/245 Reminder of hygiene compliance policies, e.g. of washing hands
• 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 1/44 using equipment having another main function to serve additionally as an antenna , e.g. means for giving an antenna an aesthetic aspectH01Q1/27 - H01Q1/34 take precedence

Abstract

An improved radio frequency identification (RFID) tag and related reader system and process are provided, wherein the RFID tag includes an on-board battery for enhanced signal transmission range, relatively rapid signal transmission speed, and optimized completion of a data transaction between the tag and a reader. The RFID tag further includes a power management system for activating the tag battery on an as-needed basis, and for thereupon enabling limited portions of the tag circuitry as required for a specific communication protocol, thereby conserving battery power and prolonging battery service life. In one preferred form, the battery is integrated with an antenna structure of single or dual mode with respect to frequency or type. This combination battery-antenna may be designed for recharging from a source of ambient energy.

Claims

1. A semi-active radio frequency identification (RFID) tag for communicating with the tag reader, said tag comprising:

tag circuitry adapted to receive and store information pertaining to a person or object associated with said tag;

an antenna for receiving and transmitting information signals relative to the tag reader;

an on-board battery for powering said tag circuitry; and

a power management system including a processor circuit for controllably coupling said on-board battery to enable selected limited portions of said tag circuitry sufficient to complete a communication protocol while prolonging battery service life;

wherein said tag circuitry comprises a plurality of circuit blocks, said power management system controllably coupling specific ones of said circuit blocks to said on-board battery each for an individually controlled time interval sufficient to complete said communication protocol, and wherein said power management system is adapted for defaulting to a passive operation mode upon battery failure and for controllably coupling specific ones of said circuit blocks to an external power source sufficient to complete said communication protocol.

2. The semi-active radio frequency identification tag of claim 1 further including means for mounting said tag onto the person or object associated therewith.

3. The semi-active radio frequency identification tag of claim 2 wherein said mounting means comprises a flexible wristband.

4. The semi-active radio frequency identification tag of claim 1 wherein said on-board battery comprises a flexible battery.

5. The semi-active radio frequency identification tag of claim 1 wherein said on-board battery is rechargeable.

6. The semi-active radio frequency identification tag of claim 1 wherein said tag circuitry comprises a wake-up circuit coupled to said antenna for activating said power management system upon detection of a communication signal from the tag reader, said processor circuit thereupon controllably enabling said selected limited portions of said tag circuitry sufficient to complete said communication protocol.

7. The semi-active radio frequency identification tag of claim 6 wherein said wake-up circuit comprises a passive wake-up circuit powered by field energy emanating from the tag reader.

8. The semi-active radio frequency identification tag of claim 6 wherein said wake-up circuit comprises an active wake-up circuit powered by said on-board battery.

9. The semi-active radio frequency identification tag of claim 1 wherein said communication protocol comprises a selected one of a plurality of different communication protocols.

10. The semi-active radio frequency identification tag of claim 1 wherein at least one of said circuit blocks comprises a sensor for monitoring a selected parameter associated with the person or object associated with said tag.

11. The semi-active radio frequency identification tag of claim 1 wherein said power management system is responsive to a communication signal from the tag reader to implement a reader-initiated communication protocol.

12. The semi-active radio frequency identification tag of claim 11 wherein said power management system is further adapted to transmit a communication signal to the tag reader to implement the tag-initiated communication protocol.

13. The semi-active radio frequency identification tag of claim 1 wherein said power management system is adapted to transmit a communication signal to the tag reader to implement the tag-initiated communication protocol.

14. The semi-active radio frequency identification tag of claim 10 wherein said processor circuit controllably enables selected limited portions of said tag circuitry in a background task mode sufficient to collect and store data, between communication sessions with the tag reader.

15. The semi-active radio frequency identification tag of claim 1 wherein said power management system is responsive in a first mode to a communication signal from the tag reader to implement a reader-initiated communication protocol, and in a second mode to implement the tag-initiated communication protocol.

16. The semi-active radio frequency identification tag of claim 15 wherein said second mode comprises an alarm mode.

17. The semi-active radio frequency identification tag of claim 1 wherein said antenna comprises a dual mode antenna adapted for operation at a first relatively low power mode, and at a second comparatively higher power mode.

18. The semi-active radio frequency identification tag of claim 17 wherein said first antenna mode comprises a magnetic field mode at a first frequency, and wherein said second antenna mode comprises an electric field mode at a second frequency.

19. The semi-active radio frequency identification tag of claim 1 wherein said antenna and said on-board battery comprise a combination unit.

20. The semi-active radio frequency identification tag of claim 1 wherein said tag circuitry comprises an integrated chip.

21. The semi-active radio frequency identification tag of claim 1 wherein said battery comprises a rectifying charge storage element.

22. The semi-active radio frequency identification tag of claim 6 wherein said wake-up circuit comprises a voltage multiplier circuit.

23. The semi-active radio frequency identification tag of claim 22 wherein said wake-up circuit includes a Schottky diode.

24. The semi-active radio frequency identification tag of claim 1 wherein said antenna comprises a tuned resonant antenna.

25. The semi-active radio frequency identification tag of claim 1 wherein said tag circuitry includes a clock element.

26. The semi-active radio frequency identification tag of claim 1 wherein said tag circuitry includes a logic memory device.

27. The semi-active radio frequency identification tag of claim 1 wherein said tag circuitry includes a load modulation circuit responsive to a detected input signal from the tag reader.

28. The semi-active radio frequency identification tag of claim 6 wherein said wake-up circuit includes a rectifier circuit and an FET switch.

29. The semi-active radio frequency identification tag of claim 6 wherein said wake-up circuit includes a switching circuit comprises a combined rectifying charge storage element/FET switch.

30. The semi-active radio frequency identification tag of claim 6 wherein said antenna comprises a dipole antenna, and further wherein said wake-up circuit is connected to said dipole antenna by a pair of oppositely connected rectifying diodes.

31. The semi-active radio frequency identification tag of claim 1 wherein said tag circuitry comprises an integrated chip coupled to an FET switch gated by a rectifying charge storage element.

32. The semi-active radio frequency identification tag of claim 31 wherein said antenna, FET switch and battery are provided as an integral unit.

33. The semi-active radio frequency identification tag of claim 1 wherein said antenna comprises a monopole E-field antenna.

34. The semi-active radio frequency identification tag of claim 33 wherein said battery comprises a portion of said antenna.

35. The semi-active radio frequency identification tag of claim 1 wherein said battery comprises a monopole H-field antenna.

36. The semi-active radio frequency identification tag of claim 35 wherein said battery comprises a portion of said antenna.

37. A semi-active radio frequency identification (RFID) tag for communicating with the tag reader, said tag comprising:

tag circuitry adapted to receive and store information pertaining to a person or object associated with said tag, said tag circuitry including a plurality of circuit blocks, at least one of said circuit block comprising a sensor;

an antenna for receiving and transmitting information signals relative to the tag reader;

an on-board battery for powering said tag circuitry; and

a power management system including a processor circuit for controllably coupling said on-board battery to enable specific ones of said circuit blocks each for an individually controlled time interval sufficient to complete a communication protocol while prolonging battery service life, wherein said power management system is adapted for defaulting to a passive operation mode upon battery failure and for controllably coupling specific ones of said circuit blocks to an external power source sufficient to complete said communication protocol.

38. The semi-active radio frequency identification tag of claim 37 further comprising a wake-up circuit coupled to said antenna for activating said power management system upon detection of a communication signal from the tag reader, said processor circuit thereupon controllably enabling said specific ones of said circuit blocks sufficient to complete said communication protocol.

39. The semi-active radio frequency identification tag of claim 38 wherein said wake-up circuit comprises a passive wake-up circuit powered by field energy emanating from the tag reader.

40. The semi-active radio frequency identification tag of claim 38 wherein said wake-up circuit comprises an active wake-up circuit powered by said on-board battery.

41. The semi-active radio frequency identification tag of claim 37 wherein said communication protocol comprises a selected one of a plurality of different communication protocols.

42. The semi-active radio frequency identification tag of claim 37 wherein said power management system is responsive to a communication signal from the tag reader to implement a reader-initiated communication protocol.

43. The semi-active radio frequency identification tag of claim 42 wherein said power management system is further adapted to transmit a communication signal to the tag reader to implement the tag-initiated communication protocol.

44. The semi-active radio frequency identification tag of claim 37 wherein said power management system is adapted to transmit a communication signal to the tag reader to implement the tag-initiated communication protocol.

45. The semi-active radio frequency identification tag of claim 37 wherein said processor circuit controllably enables selected limited portions of said tag circuitry in a background task mode sufficient to collect and store data, between communication sessions with the tag reader.

46. The semi-active radio frequency identification tag of claim 37 wherein said power management system is responsive in a first mode to a communication signal from the tag reader to implement a reader-initiated communication protocol, and in a second mode to implement the tag-initiated communication protocol.

47. The semi-active radio frequency identification tag of claim 37 wherein said antenna comprises a dual mode antenna adapted for operation at a first, relatively low power mode, and at a second, comparatively higher power mode.

48. A semi-active radio frequency identification (RFID) tag and tag reader system, comprising:

the tag reader; and

an RFID tag including tag circuitry adapted to receive and store information pertaining to a person or object associated with said tag, an antenna for receiving and transmitting information signals in the course of a communication session between said tag and said tag reader, an on-board battery for powering said tag circuitry, and a power management system including a processor circuit for controllably coupling said on-board battery to enable selected limited portions of said tag circuitry sufficient to complete said communication session while prolonging battery service life, wherein said tag circuitry comprises a plurality of circuit blocks, said power management system controllably coupling specific ones of said circuit blocks to said on-board battery each for an individually controlled time interval sufficient to complete said communication session, and wherein said power management system is adapted for defaulting to a passive operation mode upon battery failure and for controllably coupling specific ones of said circuit blocks to an external power source sufficient to complete a communication protocol.

49. The system of claim 48 wherein said tag circuitry comprises a wake-up circuit coupled to said antenna for activating said power management system upon detection of a communication signal from the tag reader, said processor circuit thereupon controllably enabling said selected limited portions of said tag circuitry sufficient to complete said communication protocol.

50. The system of claim 49 wherein said wake-up circuit comprises a passive wake-up circuit powered by field energy emanating from the tag reader.

51. The system of claim 49 wherein said wake-up circuit comprises an active wake-up circuit powered by said on-board battery.

52. The system of claim 48 wherein said communication session comprises a selected one of a plurality of different communication protocols.

53. The system of claim 48 wherein at least one of said circuit blocks comprises a sensor for monitoring a selected parameter associated with the person or object associated with said tag.

54. The system of claim 48 wherein said power management system is responsive to a communication signal from the tag reader to implement a reader-initiated communication session.

55. The system of claim 54 wherein said power management system is further adapted to transmit a communication signal to the tag reader to implement the tag-initiated communication session.

56. The system of claim 48 wherein said power management system is adapted to transmit a communication signal to the tag reader to implement a tag-initiated communication session.

57. The system of claim 48 wherein said processor circuit controllably enables selected limited portions of said tag circuitry in a background task mode sufficient to collect and store data, between communication sessions with said tag reader.

58. The system of claim 48 wherein said power management system is responsive in a first mode to a communication signal from the tag reader to implement a reader-initiated communication protocol, and in a second mode to implement the tag-initiated communication protocol.

59. The system of claim 58 wherein said second mode comprises an alarm mode.

60. The system of claim 48 wherein said antenna comprises a dual mode antenna adapted for operation at a first, relatively low power mode, and at a second, comparatively higher power mode.

61. In a semi-active radio frequency identification (RFID) tag for communicating with the tag reader, said tag comprising tag circuitry having multiple circuit blocks adapted to receive and store information pertaining to a person or object associated with said tag, an antenna for receiving and transmitting information signals relative to the tag reader, and an on-board battery for powering said tag circuitry, the tag power consumption control process comprising the steps of:

providing a power management system including a processor circuit for regulating coupling of said circuit blocks to said on-board battery;

controllably coupling specific selected ones of said circuit blocks to said on-board battery each for an individually controlled time interval sufficient to complete a specific communication protocol; and

defaulting to a passive operation mode upon battery failure and for thereupon controllably coupling specific ones of said circuit blocks to an external power source sufficient to complete said communication protocol.

62. The process of claim 61 wherein said coupling step is responsive to a communication session initiated by the tag reader.

63. The process of claim 61 wherein said coupling step is responsive to a communication session initiated by the tag.

64. The process of claim 61 wherein said coupling step is responsive to a communication session initiated by one of the tag and the tag reader.

65. The process of claim 61 wherein said coupling step operates the tag in a background task mode sufficient to collect and store data, between communication sessions with the tag reader.

66. The process of claim 61 further including the step of operating the power management system in a first mode in response to a communication signal from the tag reader to implement a reader-initiated communication protocol, and in a second mode to implement the tag-initiated communication protocol.

67. The process of claim 66 wherein said second mode comprises an alarm mode.

68. The process of claim 66 including the step of operating the antenna at a first, relatively low power in said first mode, and at a second, comparatively higher power in said second mode.

69. An electronic tag for communicating with the tag reader, said tag comprising:

tag circuitry adapted to receive and store information pertaining to a person or object associated with said tag;

an antenna for receiving and transmitting information signals relative to the tag reader;

a battery for powering said tag circuitry; and

a power management system including a processor circuit for controllably coupling said battery to enable selected portions of said tag circuitry sufficient to complete a communication protocol;

wherein said tag circuitry comprises a plurality of circuit blocks, said power management system controllably coupling specific ones of said circuit blocks to said battery each for an individually controlled time interval sufficient to complete said communication protocol, wherein said power management system is adapted for defaulting to a passive operation mode upon battery failure and for controllably coupling specific ones of said circuit blocks to an external power source sufficient to complete said communication protocol, wherein said communication protocol comprises a selected one of a plurality of different communication protocols, and wherein at least one of said circuit blocks comprises a sensor for monitoring a selected parameter associated with the person or object associated with said tag.

70. The electronic tag of claim 69 further including means for mounting said tag onto the person or object associated therewith.

71. The electronic tag of claim 69, wherein the tag comprises an RFID card, tag, label, inlet, bracelet, or other electronic device.

72. The electronic tag of claim 69 wherein said battery comprises a flexible rechargeable battery.

73. The electronic tag of claim 69 wherein said tag circuitry comprises a wake-up circuit coupled to said antenna for activating said power management system upon detection of a communication signal from the tag reader, said processor circuit thereupon controllably enabling said selected portions of said tag circuitry sufficient to complete said communication protocol.

74. The electronic tag of claim 73 wherein said wake-up circuit comprises a passive wake-up circuit powered by field energy emanating from the tag reader, or an active wake-up circuit powered by said battery.

75. The electronic tag of claim 69 wherein said power management system is responsive to a communication signal from the tag reader to implement a reader-initiated communication protocol, and wherein said power management system is further adapted to transmit a communication signal to the tag reader to implement the tag-initiated communication protocol.

76. The electronic tag of claim 69 wherein said power management system is adapted to transmit a communication signal to the tag reader to implement the tag-initiated communication protocol, and wherein said processor circuit controllably enables selected portions of said tag circuitry in a background task mode sufficient to collect and store data, between communication sessions with the tag reader.

77. The electronic tag of claim 69 wherein said power management system is responsive in a first mode to a communication signal from the tag reader to implement a reader-initiated communication protocol, and in a second mode to implement the tag-initiated communication protocol, wherein said second mode comprises an alarm mode.

78. The electronic tag of claim 69 wherein said antenna comprises a dual mode antenna adapted for operation at a first relatively low power mode, and at a second comparatively higher power mode, wherein said first antenna mode comprises a magnetic field mode at a first frequency, and wherein said second antenna mode comprises an electric field mode at a second frequency.

79. The electronic tag of claim 69 wherein said antenna and said battery comprise a combination unit, wherein said tag circuitry comprises an integrated chip, and wherein said battery comprises a rectifying charge storage element.

80. The electronic tag of claim 73 wherein said wake-up circuit comprises a voltage multiplier circuit, and wherein said wake-up circuit includes a Schottky diode.

81. The electronic tag of claim 69 wherein said antenna comprises a tuned resonant antenna, said tag circuitry includes a clock element, said tag circuitry includes a logic memory device, and wherein said tag circuitry includes a load modulation circuit responsive to a detected input signal from the tag reader.

82. The electronic tag of claim 73 wherein said wake-up circuit includes a rectifier circuit and an FET switch, and wherein said antenna comprises a dipole antenna, and further wherein said wake-up circuit is connected to said dipole antenna by a pair of oppositely connected rectifying diodes.

83. The electronic tag of claim 69 wherein said tag circuitry comprises an integrated chip coupled to an FET switch gated by a rectifying charge storage element, wherein said antenna, FET switch and battery are provided as an integral unit.

84. The electronic tag of claim 69 wherein said antenna comprises a monopole E-field antenna, and wherein said battery comprises a portion of said antenna.

85. The electronic tag of claim 69 wherein said battery comprises a monopole H-field antenna, and wherein said battery comprises a portion of said antenna.