Battery-assisted backscatter RFID transponder

• US 20060012464A1
• Filed: 06/30/2005
• Published: 01/19/2006
• Est. Priority Date: 07/01/2004
• Status: Abandoned Application

• Current Assignee: PowerID Ltd.
• Original Assignee: PowerID Ltd.
• Inventors: Nitzan, Zvi, Guri, Gaby, Lavee, Doron
• Application Number:
  US11/169,702
• Publication Number:
  US 20060012464A1
• Time in Patent Office: Days
• US Class Current: 340/10.100
• CPC Class Codes: G06K 19/0702 the arrangement including a battery
• CPC Class Codes: G06K 19/0705 the battery being connected to a power saving arrangement
• CPC Class Codes: G06K 19/0707 the arrangement being capable of collecting energy from external energy sources, e.g. thermocouples, vibration, electromagnetic radiation G06K19/0702 takes precedence
• CPC Class Codes: G06K 19/0712 the arrangement being capable of triggering distinct operating modes or functions dependent on the strength of an energy or interrogation field in the proximity of the record carrier active means for hindering electromagnetic reading or writing G06K19/07336
• 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 19/07749 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: 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 9/16 with feed intermediate between the extremities of the antenna, e.g. centre-fed dipole H01Q9/44 takes precedence

Abstract

A radio frequency transponder includes at least one battery, which is coupled to provide electrical power for operating the transponder and at least one antenna, which is configured to receive and backscatter RF interrogation radiation from an interrogation device. An integrated circuit is arranged to store a code including information and, powered only with energy provided by the battery, to vary a radiation characteristic of the antenna responsively to the code so as to modulate the information onto the backscattered radiation.

Claims

1. A radio frequency (RF) transponder, comprising:

at least one battery, which is coupled to provide electrical power for operating the transponder;

at least one antenna, which is configured to receive and backscatter RF interrogation radiation from an interrogation device; and

an integrated circuit (IC), which is arranged to store a code comprising information and, powered only with energy provided by the battery, to vary a radiation characteristic of the antenna responsively to the code so as to modulate the information onto the backscattered radiation.

2. The transponder according to claim 1, and comprising a substrate having at least one of the IC, the at least one antenna and the at least one battery disposed thereon.

3. The transponder according to claim 2, wherein the at least one battery comprises at least a printed anode layer, a printed electrolyte layer and a printed cathode layer disposed in at least one of a co-planar and a co-facial configuration, wherein the electrolyte layer is disposed between the anode layer and the cathode layer.

4. The transponder according to claim 2, wherein the substrate is flexible.

5. The transponder according to claim 1, wherein the transponder has a thickness no greater than 1 mm and a bending radius no greater than 25 mm.

6. The transponder according to claim 1, wherein the transponder is attached to an object and wherein at least part of the information in the IC is related to the object.

7. The transponder according to claim 1, wherein the transponder is adapted to be attached around a corner of an object so that the at least one battery is oriented in a first plane and the at least one antenna is oriented in a second plane different from the first plane.

8. The transponder according to claim 1, wherein the at least one antenna is selected from the group consisting of at least one of a monopole, a bent monopole, a dipole, a bent dipole, a patch, an array antenna and a combination thereof.

9. The transponder according to claim 1, wherein the at least one antenna is configured to receive and backscatter the interrogation radiation in one of an ultra-high frequency (UHF) range and a microwave frequency range.

10. The transponder according to claim 1, wherein the at least one antenna is arranged to receive and backscatter transverse electromagnetic (TEM) radiation.

11. The transponder according to claim 1, wherein the at least one antenna comprises a feed-point, and wherein the radiation characteristic comprises a radar cross-section (RCS) of the at least one antenna, and wherein the IC is arranged to vary a load impedance at the feed-point of the at least one antenna so as to vary the RCS of the at least one antenna between two or more different RCS values.

12. The transponder according to claim 11, wherein the IC comprises a solid-state switch operatively coupled to the feed-point of the at least one antenna, which is arranged to switch the load impedance between a first impedance and a second impedance, responsively to a binary representation of the code.

13. The transponder according to claim 11, wherein the IC is arranged to introduce a low resistive load condition at the feed-point of the at least one antenna so as to maximize at least one of the two or more RCS values, thereby maximizing a communication range of the transponder.

14. The transponder according to claim 11, wherein the IC is arranged to maximize a modulation depth defined as a ratio between two of the two or more RCS values.

15. The transponder according to claim 14, wherein the at least one antenna and the IC are arranged to jointly maximize the modulation depth and a communication range of the transponder.

16. The transponder according to claim 1, wherein the interrogation radiation received by the at least one antenna has a first power level, and wherein the at least one antenna and the IC are arranged to backscatter the interrogation radiation at a second power level that is greater than 75% of the first power level.

17. The transponder according to claim 16, wherein the second power level is greater than 95% of the first power level.

18. The transponder according to claim 1, wherein the IC is configured to comply with an operation protocol defining two or more operational modes.

19. The transponder according to claim 18, wherein the IC comprises an energy saving module, which is arranged to activate and deactivate parts of the transponder responsively to the operational modes so as to reduce an energy consumption from the at least one battery.

20. The transponder according to claim 18, wherein the protocol comprises at least one of a transponder-talks-first (TTF) and a reader-talks-first (RTF) protocol.

21. The transponder according to claim 20, wherein the protocol comprises the RTF protocol, and wherein the IC is configured to analyze signals carried by the interrogation radiation, to progressively activate components of the transponder responsively to the analyzed signals so as to reduce an energy consumption from the at least one battery, to assess a relevance of the interrogation radiation to the transponder based on the analyzed signals, and to enable the transponder to react to the interrogation radiation based on the relevance.

22. The transponder according to claim 20, wherein the IC is arranged to evaluate one or more timeout conditions and to deactivate predetermined components of the transponder responsively to the timeout conditions after having detected a presence of the interrogation radiation.

23. The transponder according to claim 1, wherein the IC comprises a battery status indicator, which is configured to indicate an availability of sufficient electrical power from the at least one battery, and wherein the IC is configured to draw electrical power from the interrogation radiation responsively to a reported unavailability of sufficient battery power as determined by the battery status indicator.

24. The transponder according to claim 1, and comprising at least one sensor, wherein the IC is arranged to receive an indication of a local condition in a vicinity of the transponder from the at least one sensor.

25. The transponder according to claim 1, and comprising an energy conversion circuit, which is arranged to draw excess power from the interrogation radiation, when the excess power is available, and to perform at least one of powering the IC and charging the at least one battery using the drawn excess power.

26. The transponder according to claim 1, wherein the IC is arranged to decode and react to interrogation data carried by the interrogation radiation, the interrogation data comprising at least one of a command relating to an operation of the transponder and input data to be written to the transponder.

27. A radio frequency (RF) transponder, comprising:

at least one battery, which is coupled to provide electrical power for operating the transponder;

at least one antenna, which is configured to receive and backscatter RF interrogation radiation from an interrogation device; and

an integrated circuit (IC), which is arranged to store a code comprising information and, powered with at least one of energy provided by the battery and excess power from the interrogation radiation, to vary a radiation characteristic of the antenna responsively to the code so as to modulate the information onto the backscattered radiation

28. A method for transmitting information from a radio frequency (RF) transponder, comprising:

providing a battery for operating the transponder;

configuring an antenna to backscatter RF interrogation radiation that is transmitted from an interrogation device; and

varying a radiation characteristic of the antenna responsively to the information so as to modulate the information onto the backscattered radiation, wherein the energy used to vary the radiation characteristic is not derived from the interrogation radiation.

29. The method according to claim 28, wherein providing the battery comprises applying a printed battery to a substrate having at least one of the IC and the antenna disposed thereon.

30. The method according to claim 28, wherein the battery is no greater than 1 mm thick.

31. The method according to claim 30, wherein the battery comprises a flexible thin-layer open liquid-state electrochemical cell comprising a first layer of insoluble negative electrode, a second layer of insoluble positive electrode and a third layer of aqueous electrolyte, the third layer being disposed between the first and second layers and including:

(a) a deliquescent material for keeping the open cell wet at all times;

(b) an electroactive soluble material for obtaining required ionic conductivity; and

(c) a water-soluble polymer for obtaining a required viscosity for adhering the first and second layers to the third layer.

32. The method according to claim 28, wherein providing the battery and configuring the antenna comprise disposing the battery and the antenna on a flexible substrate.

33. The method according to claim 32, wherein the transponder has a thickness no greater than 1 mm and a bending radius no greater than 25 mm.

34. The method according to claim 28, and comprising attaching the transponder to an object, wherein at least part of the information is related to the object.

35. The method according to claim 34, wherein attaching the transponder comprises fixing the transponder around a corner of the object so that the battery is oriented in a first plane and the antenna is oriented in a second plane different from the first plane.

36. The method according to claim 28, wherein configuring the antenna comprises providing at least one of a monopole, a bent monopole, a dipole, a bent dipole, a patch, an array antenna and a combination thereof.

37. The method according to claim 28, wherein configuring the antenna comprises receiving and backscattering the interrogation radiation in one of an ultra-high frequency (UHF) range and a microwave frequency range.

38. The method according to claim 28, wherein coupling the antenna comprises receiving and backscattering transverse electromagnetic (TEM) radiation.

39. The method according to claim 28, wherein varying the radiation characteristic comprises modulating a radar cross-section (RCS) of the antenna.

40. The method according to claim 39, wherein varying the radiation characteristic comprises varying a load impedance at a feed-point of the antenna, so as to modulate the RCS of the antenna between two or more different RCS values.

41. The method according to claim 40, wherein varying the load impedance comprises switching the load impedance between a first impedance and a second impedance, responsively to a binary representation of the code.

42. The method according to claim 40, wherein varying the load impedance comprises introducing a low resistive load condition at the feed-point of antenna so as to maximize at least one of the two or more RCS values, thereby maximizing a communication range of the transponder.

43. The method according to claim 40, wherein varying the load impedance comprises maximizing a modulation depth defined as a ratio between two of the two or more RCS values.

44. The method according to claim 43, wherein varying the load impedance comprises jointly maximizing the modulation depth and a communication range of the transponder.

45. The method according to claim 28, further comprising the step of drawing electrical power from the interrogation radiation and powering the transponder with the drawn power when the battery is unable to provide sufficient electrical power for operating the transponder.

46. The method according to claim 28, and comprising drawing excess power from the interrogation radiation, when excess power is available, and performing at least one of powering the IC and charging the battery using the drawn excess power.

47. The method according to claim 28, wherein backscattering the interrogation radiation comprises decoding and reacting to interrogation data carried by the interrogation radiation, the interrogation data comprising at least one of a command relating to an operation of the transponder and input data to be written to the transponder.

48. A method for transmitting information from a radio frequency (RF) transponder, comprising:

configuring an antenna to receive an-interrogation radiation at a first power level from an interrogation device and to backscatter the interrogation radiation at a second power level that is greater than 75% of the first power level;

storing a code comprising the information; and

varying a radiation characteristic of the antenna responsively to the code so as to modulate the information onto the backscattered radiation.

49. The method according to claim 48, wherein the second power level is greater than 95% of the first power level.

50. The method according to claim 48, wherein configuring the antenna comprises disposing the antenna on a flexible substrate.

51. The method according to claim 48, wherein the transponder has a thickness no greater than 1 mm and a bending radius no greater than 25 mm.

52. The method according to claim 48, further comprising attaching the transponder to an object, wherein at least part of the information is related to the object.

53. The method according to claim 52, wherein the transponder comprises a battery, and wherein attaching the transponder comprises fixing the transponder around a corner of the object so that the battery is oriented in a first plane and the antenna is oriented in a second plane different from the first plane.

54. The method according to claim 48, wherein configuring the antenna comprises providing at least one of a monopole, a bent monopole, a dipole, a bent dipole, a patch, an array antenna and a combination thereof.

55. The method according to claim 48, wherein configuring the antenna comprises receiving and backscattering the interrogation radiation in one of an ultra-high frequency (UHF) range and a microwave frequency range.

56. The method according to claim 48, wherein configuring the antenna comprises receiving and backscattering transverse electromagnetic (TEM) radiation.

57. The method according to claim 48, wherein varying the radiation characteristic comprises modulating a radar cross-section (RCS) of the antenna.

58. The method according to claim 48, wherein varying the radiation characteristic comprises varying a load impedance at a feed-point of the antenna, so as to modulate the RCS of the antenna between two or more different RCS values.

59. The method according to claim 58, wherein varying the load impedance comprises switching the load impedance between a first impedance and a second impedance, responsively to a binary representation of the code.

60. The method according to claim 58, wherein varying the load impedance comprises introducing a low resistive load condition at the feed-point of the antenna so as to maximize at least one of the two or more RCS values, thereby maximizing a communication range of the transponder.

61. The method according to claim 58, wherein varying the load impedance comprises maximizing a modulation depth defined as a ratio between two of the two or more RCS values.

62. The method according to claim 61, wherein varying the load impedance comprises jointly maximizing the modulation depth and a communication range of the transponder.

63. The method according to claim 48, and comprising drawing excess power from the interrogation radiation when excess power is available, and performing at least one of powering the IC and charging the battery using the drawn excess power.

64. The method according to claim 48, wherein receiving the interrogation radiation comprises decoding and reacting to interrogation data carried by the interrogation radiation, the interrogation data comprising at least one of a command relating to an operation of the transponder and input data to be written to the transponder.

65. A radio-frequency identification (RFID) system, comprising:

at least one interrogation device, which is configured to transmit RF interrogation radiation to RF transponders and to receive and decode backscatter-modulated radiation from the RF transponders responsively to the interrogation radiation;

at least one radio frequency (RF) transponder, comprising;

at least one battery, which is coupled to provide electrical power for operating the transponder;

at least one antenna, which is arranged to receive and backscatter the interrogation radiation from the at least one interrogation device; and

an integrated circuit (IC), which is arranged to store a code comprising information and, powered only with energy provided by the battery, to vary a radiation characteristic of the antenna responsively to the code so as to modulate the information onto the backscattered radiation; and

at least one data processing device for processing data decoded by the at least one interrogation device from the backscattered modulated radiation.

66. The system according to claim 65, wherein the at least one transponder comprises a substrate having at least one of the IC, the at least one antenna and the at least one battery disposed thereon.

67. The system according to claim 66, wherein the at least one battery comprises at least a printed anode layer, an electrolyte layer and a printed cathode layer disposed on top of one another on the substrate.

68. The system according to claim 66, wherein the substrate is flexible.

69. The system according to claim 65, wherein the at least one transponder has a thickness no greater than 1 mm and a bending radius no greater than 25 mm.

70. The system according to claim 65, wherein the at least one transponder is adapted to be attached to an object and wherein at least part of the information in the IC is related to the object.

71. The system according to claim 70, wherein the at least one transponder is adapted to be attached around a corner of the object so that the at least one battery is oriented in a first plane and the at least one antenna is oriented in a second plane different from the first plane.

72. The system according to claim 65, wherein the at least one antenna is selected from the group consisting of at least one of a monopole, a bent monopole, a dipole, a bent dipole, a patch, an array antenna and a combination thereof.

73. The system according to claim 65, wherein the at least one antenna is configured to receive and backscatter the interrogation radiation in one of an ultra-high frequency (UHF) range and a microwave frequency range.

74. The system according to claim 65, wherein the at least one antenna is arranged to receive and backscatter transverse electromagnetic (TEM) radiation.

75. The system according to claim 65, wherein the at least one antenna comprises a feed-point, and wherein the radiation characteristic comprises a radar cross-section (RCS) of the at least one antenna, and wherein the IC is arranged to vary a load impedance at the feed-point of the at least one antenna so as to vary the RCS of the antenna between two or more different RCS values.

76. The system according to claim 75, wherein the IC comprises a solid-state switch operatively coupled to the feed-point of the at least one antenna, which is arranged to switch the load impedance between a first impedance and a second impedance, responsively to a binary representation of the code.

77. The system according to claim 75, wherein the IC is arranged to introduce a low resistive load condition at the feed-point of the at least one antenna so as to maximize at least one of the two or more RCS values, thereby maximizing a communication range of the at least one transponder.

78. The system according to claim 75, wherein the IC is arranged to maximize a modulation depth defined as a ratio between two of the two or more RCS values.

79. The system according to claim 78, wherein the at least one antenna and the IC are arranged to jointly maximize the modulation depth and a communication range of the at least one transponder.

80. The system according to claim 65, wherein the interrogation radiation received by the at least one antenna has a first power level, and wherein the at least one antenna and the IC are arranged to backscatter the interrogation radiation at a second power level that is greater than 75% of the first power level.

81. The system according to claim 80, wherein the second power level is greater than 95% of the first power level.

82. The system according to claim 65, wherein the at least one transponder is configured to comply with an operation protocol defining two or more operational modes.

83. The system according to claim 82, wherein the IC comprises an energy saving module, which is arranged to activate and deactivate parts of the at least one transponder responsively to the operational modes so as to reduce an energy consumption from the at least one battery.

84. The system according to claim 83, wherein the protocol comprises at least one of a transponder-talks-first (TTF) and a reader-talks-first (RTF) protocol.

85. The system according to claim 84, wherein the protocol comprises the RTF protocol, and wherein the IC is configured to analyze signals carried by the interrogation radiation, to progressively activate components of the at least one transponder responsively to the analyzed signals so as to reduce an energy consumption from the at least one battery, to assess a relevance of the interrogation radiation to the at least one transponder based on the analyzed signals, and to enable the at least one transponder to react to the interrogation radiation based on the relevance.

86. The system according to claim 84, wherein the IC is arranged to evaluate one or more timeout conditions and to deactivate predetermined components of the at least one transponder responsively to the timeout conditions after having detected a presence of the interrogation radiation.

87. The system according to claim 65, wherein the IC comprises a battery status indicator, which is configured to indicate an availability of sufficient electrical power from the at least one battery, and wherein the IC is configured to draw electrical power from the interrogation radiation responsively to a reported unavailability of sufficient battery power as determined by the battery status indicator.

88. The system according to claim 65, wherein the at least one transponder comprises a sensor, which is arranged to sense a local condition in a vicinity of the at least one transponder and to indicate the local condition to the IC.