INDUCTIVELY COUPLED PASSIVE RESPONDER AND INTERROGATOR UNIT HAVING MULTIDIMENSION ELECTROMAGNETIC FIELD CAPABILITIES

• US 3,689,885 A
• Filed: 09/15/1970
• Issued: 09/05/1972
• Est. Priority Date: 09/15/1970
• Status: Expired due to Term

• Current Assignee: Leon M. Kaplan, Thomas A. Kriofsky
• Original Assignee: Leon M. Kaplan, Thomas A. Kriofsky
• Inventors: Leon, M. Kaplan, Thomas, A. Kriofsky
• Primary Examiner(s): Donald J. Yusko
• Application Number:
  US05/072,483
• Time in Patent Office: 721 Days
• Field of Search: 340/149,152 325/8,15,51 343/6.5,6.8
• US Class Current: 340/10.1
• CPC Class Codes: B61L 25/043 using inductive tags
• 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 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G07C 9/28 the pass enabling tracking or indicating presence

Abstract

An interrogator-responder system wherein the responder is a passive responder receiving an inductively coupled electromagnetic power field from an interrogator unit and generating an unique predetermined electromagnetic coded information field in response to the presence of the electromagnetic power field. The interrogator unit has multidimensional recognition capabilities for detecting the electromagnetic coded information field independent of the orientation of the responder for two dimensional or three dimensional capabilities.

Claims

1. An interrogator-responder system for providing an output signal having an information content corresponding to an uniquely coded information field of a particular responder, and generated in said responder, in response to the interrogator, and comprising, in combination:

an interrogator means for establishing an electromagnetic AC power field and receiving an electromagnetic coded information field, and generating the output signal in response thereto;

a responder tag means positionable in AC power field and coded information field energy exchange relationship to said interrogator means for receiving said AC power field and generating the uniquely coded information field in response thereto;

said interrogator means comprising;

a power supply means for providing a controlled source of electric energy;

a power signal generator means for receiving said controlled electric energy and generating a power signal in response thereto;

a power field generator means for receiving said power signal and generating said AC power field having a first preselected frequency for inductive coupling into said responder tag means;

a coded information field receiver means for receiving said uniquely coded information field from said responder tag means and said uniquely coded information field having a second preselected frequency different from said first preselected frequency;

coded information field detection means powered by said controlled source of electric energy, for detecting the existance of said coded information field in said coded information field receiver means and generating a detected coded signal in response thereto;

information capture and validation logic means, powered by said controlled electric energy, for receiving said detected coded signal from said coded information field detection means and generating an output signal having an information content corresponding to said uniquely coded information field in response thereto;

time-base signal generating means for generating a time-base signal and providing said time-base signal to said power signal generator and to said logic means for synchronization;

said responder tag means is free of active power supplies and comprises;

power field receiver means for receiving said AC power field from said power field generator of said interrogator means and providing DC tag power signals in response thereto;

carrier time-base signal generator means for receiving said DC tag power signal and generating a carrier time-base signal at said second preselected frequency in response thereto;

a code signal generator powered by said DC tag power signal for repetitively generating a unique code signal at a third frequency different from said second frequency in response to said DC tag power input thereto;

coded information signal generator means powered by said DC tag power signal for receiving said carrier time-base signal at said second frequency and receiving said unique code signal at said third frequency and modulating said carrier time-base signal with said unique code signal to generate a coded information signal unique to said responder tag;

coded information field generator for receiving said coded information signal and generating said coded information field for said inductive coupling into said coded information field recEiver of said interrogator means.

2. The arrangement defined in claim 1 wherein said code signal generator further comprises:

binary signal generating means for generating an unique digital binary code signal having a plurality of information bits and a first portion of said plurality of information bits comprises a common binary bit sequence for synchronizing said coded information signal, and a second portion of said plurality of information bits comprises an unique binary bit sequence;

said logic means of said interrogator means further comprises;

sequence detection means for detecting said common binary bit sequence in said detected coded signal of said coded information signal detector and generating said output signal in response to said unique binary bit sequence in said coded information field.

3. The arrangement defined in claim 2 wherein said interrogator is inductively coupled to said responder tag means for providing said AC power field to said responder tag means and receiving said coded information field from said responder tag means, and said power field generator and said coded information field receiver of said interrogator means together comprise:

a plurality of interrogator coils oriented in a preselected geometric array and each of said coils is sequentially operable in a plurality of conditions, a first of said conditions comprising a field generating condition for generating said AC power field and a second of said conditions comprising a coded information field receiving condition for receiving said coded information field (1) from said responder tag means;

said interrogator means further comprising;

switching means coupled to said plurality of interrogator coils for sequentially switching each of said plurality of interrogator coils from each of said plurality of conditions to another of said plurality of conditions at a predetermined switching frequency and in a preselected sequential order;

said coded information signal generator of said responder tag means further comprises;

a responder tag coil means;

said power field receiver of said responder tag means further comprises;

a coil means for inductively coupling said AC power field into said responder tag;

DC voltage magnitude limiting means for limiting the magnitude of said DC tag power signals generated by said power field receiver means in response to said AC power input field.

4. The arrangement defined in claim 3 wherein:

said plurality of interrogator coils comprises three coils and said preselected geometric array comprises a orthogonal array of said coils, and said switching means further comprises means for at least switching each of said coils from said first condition to said second condition and from said second condition to said first condition in a predetermined order to provide two of said three coils simultaneously in said first condition and one coil in said second condition whereby said interrogator detects said coded information signal for said responder tag in any geometric orientation with respect to said interrogator coils of said interrogator means.

5. The arrangement defined in claim 4 wherein:

said responder tag is positionable in regions adjacent the intersection of the axis of said mutually orthogonal interrogator coils.

6. The arrangement defined in claim 5 wherein:

said first preselected frequency and said third preselected frequency are each on the order of 50 kiloHertz, and said second preselected frequency is on the order of 450 kiloHertz.

7. The arrangement defined in claim 4 wherein:

said coded information signal generating means of said responder tag means further comprises;

means for amplitude modulating said carrier time-base signal with said code signal.

8. The arrangement defined in claim 4 wherein:

said coded information signal generating means of said responder tag means further comprises;

means for phase modulaTing said carrier time-base signal with said code signal.

9. The arrangement defined in claim 4 wherein:

said coded information signal generating means of said responder tag means further comprises;

means for frequency modulating said carrier time-base signal with said code signal.

10. The arrangement defined in claim 2 wherein:

said interrogator means is inductively coupled to said responder tag means for providing said AC power input field to said responder tag means and for receiving said coded information field from said responder tag means;

said power field generator of said interrogator means comprises;

a pair of elongated interrogator coils, each of said pair of elongated interrogator coils having a long axis and a short axis and geometrically arranged to have said long axis perpendicular to each other for simultaneously generating said AC power field;

said coded information field receiver of said interrogator means comprises;

a receiving coil positioned in close proximity to said pair of interrogator coils;

said coded information field generator of said responder tag means further comprises;

a responder tag coil means;

said power field receiver of said responder tag means further comprises;

a coil means for inductively coupling said power field into said responder tag;

DC voltage limiting means for limiting the magnitude of said DC tag power signal generated by said loop-stick means in response to said AC power field.

11. The arrangement defined in claim 10 wherein:

said interrogator coils and said receiver coil are enclosed in a field transmitting case means.

12. The arrangement defined in claim 11 wherein:

said first preselected frequency and said third preselected frequency are on the order of 50 kiloHertz and said second preselected frequency is on the order of 450 kiloHertz.

13. The arrangement defined in claim 10 wherein:

said coded information signal generating means of said responder tag means further comprises;

means for amplitude modulating said carrier time-base signal with said code signal.

14. The arrangement defined in claim 10 wherein:

said coded information signal generating means of said responder tag means further comprises;

means for phase modulating said carrier time-base signal with said code signal.

15. The arrangement defined in claim 10 wherein:

said coded information signal generating means of said responder tag means further comprises;

means for frequency modulating said carrier time-base signal with said code signal.

16. The arrangement defined in claim 2 wherein:

said power field generator means and said coded information field receiver means together comprise a plurality of three mutually orthogonal coils for inductive coupling between said responder tag and said interrogator means, and said mutually orthogonal coils are sequentially operated in a power transmit condition, a signal receiving condition and a null condition in a preselected sequence.

17. The arrangement defined in claim 2 wherein:

said power field generator means and said coded information field receiver means comprise;

a pair of mutually orthogonal coils, a first of said pair of coils comprising said power field generator means; and

a second of said pair of coils comprises a coded information field receiver for receiving a coded information field from said responder tag.

18. The arrangement defined in claim 2 wherein:

said interrogator means further comprises means for pulsing said power field provided to said responder tag.

19. The arrangement defined in claim 2 and further comprising:

clock generator means for generating a clock signal having a predetermined frequency substantially twice the frequency of said AC power field provided to said responder tag.

20. The arrangement defined in claim 19 wherein:

said coded information sIgnal detection means further comprises;

a notch filter for receiving said coded information signal from said coded information field receiver means and filtering said coded information signal to remove components of interrogator power cross coupled therein from said power signal transmitter;

an amplifier-demodulator stage for receiving the output from said notch filter means for amplifying the signal received from the notch filter and demodulating said amplified signal;

an amplifier means for further amplifying said amplified-demodulated signal; and

a logic buffer means for receiving the amplified-modulated signal and converting same to said detected coded signal having a predetermined voltage and a predetermined current.

21. The arrangement defined in claim 20 wherein:

said logic means further comprises a validation and capture portion for validating the true information content of said detected coded signal applied thereto from said coded information signal detection means and providing display thereof on a preselected display means for the condition of said information signal validated.

22. The arrangement defined in claim 21 wherein:

said logic means further comprises;

a digital counter having a predetermined plurality of stages, a first portion of said stages for generating control signals, and a second portion of said stages for generating opposite phased signals, and said opposite phased signals applied to said validation and capture portion;

said control signals for providing sequencing control to said power signal transmitter means and said coded information signal receiver means for sequencing in a predetermined sequence, and for pulsing said power signal generator to provide a pulsed power field to said responder tag.

23. A passive responder tag means comprising, in combination:

a power field receiver means for receiving an AC power field inductively coupled thereto and providing DC tag power signals in response thereto;

carrier time-base signal generating means for receiving said DC tag power signal and generating an AC carrier time-base signal at a first predetermined frequency in response thereto;

a code signal generator powered by said DC tag power signal for repetitively generating an unique code signal at a second frequency different from said first frequency in response to said DC tag power signal input thereto;

coded information signal generating means powered by said DC tag power signal for receiving said carrier time-base signal at said first frequency and for receiving said unique code signal at said second frequency and for modulating said carrier time-base signal with said unique code signal to generate a coded information signal unique to said tag responder;

coded information field generating means for receiving said coded information signal and generating an electromagnetic coded information field in regions external of said responder tag means.

24. The arrangement defined in claim 23 wherein:

said code signal generator means further comprises binary signal generating means for generating an unique binary code signal having a plurality of information bits and a first portion of said plurality of information bits comprises a common binary bit sequence for keying said coded information signal, and a second portion of said plurality of binary information bits comprises an unique binary bit sequence;

said coded information field generator means further comprises;

a responder tag coil means;

said power field receiver means further comprises;

a coil means for inductively coupling said AC power field into said responder tag means; and

DC voltage limiting means for limiting the magnitude of said DC tag power signals.

25. The arrangement defined in claim 24 wherein:

said coil means comprises four diode bridge means for converting said AC power input signal to said DC tag power signals and said DC volTage limiting means comprises a zener diode.

26. The arrangement defined in claim 25 wherein:

said coded information signal generating means further comprises amplitude modulation means for amplitude modulating said carrier time-base signal with said code signal.

27. The arrangement defined in claim 24 wherein:

said coded information signal generating means further comprises phase modulation means for phase modulating said carrier time-base signal with said code signal.

28. The arrangement defined in claim 24 wherein:

said coded information signal generating means further comprises frequency modulation means for frequency modulating said carrier time-base signal with said code signal.

29. The arrangement defined in claim 24 wherein:

said binary signal generating means further comprises a binary code generator, and said common binary bit sequence in said binary code signal is represented by an eight bit binary notation P1111110; and

said first preselected frequency of said carrier time-base signal is on the order of 450 kiloHertz and said second preselected frequency of said code signal is on the order of 50 kiloHertz.

30. The arrangement defined in claim 25 wherein:

said binary code generator comprises a metal oxide multiplexor.

31. The arrangement defined in claim 25 wherein:

said binary code generator comprises a complimentary metal oxide multiplexor.

32. The arrangement defined in claim 25 wherein:

said binary code generator comprises a silicon on sapphire multiplexor.

33. An interrogator-responder system for providing an output signal having an information content corresponding to an uniquely coded information field indicative of a particular responder and generated therein in response to the interrogator and comprising, in combination:

an interrogator means for establishing an electromagnetic AC power field and receiving an electromagnetic coded information field, and generating the output signal in response thereto;

a responder tag means positioned in AC power field and coded information field energy exchange relationship to said interrogator means;

said responder tag means is free of active power supplies and comprises;

power field receiver means for receiving said AC power field from said interrogator means and providing DC tag power signals in response thereto;

carrier time-base signal generator means for receiving said DC tag power signal and generating a carrier time-base signal at a second preselected frequency in response thereto;

a code signal generator powered by said DC tag power signal for repetitively generating a unique code signal at a third frequency in response to said DC tag power input thereto;

coded information signal generator means powered by said DC tag power signal for receiving said carrier time-base signal at said second frequency and receiving said unique code signal at said third frequency and modulating said carrier time-base signal with said unique code signal to generate a coded information signal unique to said responder tag;

coded information field generator for receiving said coded information signal and generating said coded information field for said inductive coupling into said coded information field receiver of said interrogator means.

34. An interrogator-responder system for providing an output signal having an information content corresponding to an uniquely coded information field indicative of a particular responder and generator therein in response to the interrogator and comprising, in combination:

an interrogator means for establishing an AC electromagnetic power field and receiving an electromagnetic coded information field, and generating the output signal in response thereto;

a responder tag means positionable in power field and coded information field energy exchange relationship to said interrogator means for receiving saiD AC power field and generating said uniquely coded information field in response thereto;

said interrogator means comprising;

a power supply means for providing a controlled source of electric energy;

a power signal generator means for receiving said controlled electric energy and generating a power signal in response thereto;

a power field generator means for receiving said power signal and generating said AC power field having a first preselected frequency for inductive coupling into said responder tag means;

a coded information field receiver means for receiving the uniquely coded information field from said responder tag means and the uniquely coded information field having a second preselected frequency different from said first preselected frequency;

coded information detection means powered by said controlled source of electric energy for detecting the existence of said coded information field in said coded information field receiver means and generating a detected coded signal in response thereto;

information capture and logic means, powered by said controlled electric energy, for receiving said detected coded signal from said coded information field detection means and generating an output signal having an information content corresponding to said uniquely coded information field in response thereto; and

time base signal generating means for generating a time base signal and providing said time base signal to said power signal generator and to said logic means for synchronization.

35. An interrogator means for establishing an AC electromagnetic power field and receiving and identifying an electromagnetic coded information field transmitter thereto, and generating an output signal in response to said identified electromagnetic coded information field, and comprising:

a power supply means for providing a controlled source of electric energy;

a power signal generator means for receiving said controlled electric energy and generating a power signal in response thereto;

a power generator means for receiving said power signal and generating the AC power field having a first preselected frequency for transmitting said AC power field to regions remote the interrogator;

a coded information field receiver means for receiving a coded information field from regions esternal to the interrogator and said coded information field having a second preselected frequency different from said first preselected frequency;

coded information field detection means powered by said controlled source of electric energy for detecting the existence of said coded information field in said coded information field receiver means and generating a detected coded signal in response thereto;

information capture and validation logic means powered by said controlled source of electric energy for receiving said detected coded signal from said coded information field detection means and generating an output signal having an information content corresponding to said uniquely coded information field in response thereto; and

time base signal generating means for generating time base signal and providing said time base signal to said power signal generator and to said information capture and validation logic means for synchronization.

36. The arrangement defined in claim 35 wherein said power field generator and said coded information field receiver together comprise:

a plurality of interrogator coils oriented in a preselected geometric array and each of said coils is sequentially operable in a plurality of conditions, a first of said conditions comprising a power field generating condition for generating said power field and transmitting said power field to regions remote the interrogator and the second of said conditions comprising a coded information field receiving condition for receiving said uniquely coded information field from regions external the interrogator; and

said interrogator means further compriSing;

switching means coupled to said plurality of interrogator coils for sequentially switching each of said plurality of interrogator coils from each of said plurality of conditions to another of said plurality of conditions at a predetermined switching frequency and in a preselected sequential order.

37. The arrangement defined in claim 36 wherein:

said plurality of interrogator coils comprises three coils and said preselected geometric array comprises an orthogonal array of said coils, and said switching means further comprises means for at least switching each of said coils from said first condition to said second condition and from said second condition to said first condition in a predetermined order to provide two of said three coils simultaneously in said first condition and one coil in said second condition whereby said interrogator detects said coded information signal for said responder tag in any geometric orientation with respect to said interrogator coils of said interrogator means.

38. The arrangement defined in claim 36 wherein:

said first preselected frequency is on the order of 50 kH and said second preselected frequency is on the order of 450 kH.

39. The arrangement defined in claim 36 wherein said validation and logic means of said interrogator further comprises:

sequence detection means for detecting a unique binary bit sequence in the detected coded signal of said coded information signal detector and generating said output signal in response to said unique binary bit sequence in said coded information field.

40. The arrangement defined in claim 36 wherein:

said power field generator of said interrogator means comprises;

a pair of elongated interrogator coils, each of said pair of elongated interrogator coils having a long axis and a short axis and geometrically arranged to have said long axis perpendicular to each other for simultaneously generating said AC power field;

said coded information field receiver of said interrogator means comprises;

a receiver coil positioned in close proximity to said pair of interrogator coils.