Proximity identification system with lateral flux magnetic rod coupling

• US 4,888,474 A
• Filed: 06/08/1988
• Issued: 12/19/1989
• Est. Priority Date: 06/08/1988
• Status: Expired due to Fees

• Current Assignee: Charles A. Walton
• Original Assignee: Charles A. Walton
• Inventors: Walton, Charles A.
• Primary Examiner(s): Pitts, Harold I.
• Application Number:
  US07/203,944
• Time in Patent Office: 559 Days
• Field of Search: 340/941, 235/449, 235/380, 364/424.02
• US Class Current: 235/449
• CPC Class Codes: G06K 7/10316 using at least one antenna particularly designed for interrogating the wireless record carriers antennas in general H01Q1/22
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil

Abstract

A reader section has an oscillator for providing a power signal to a reader antenna. The reader antenna is constructed of a ferromagentic rod having primary and secondary windings. The primary windings are concentrated near the end of the ferromagnetic rod. A transformer is connected to the oscillator and the reader antenna and separates the power signal from an identifier signal. An identifier section has an identifier antenna which is constructed of a ferromagnetic rod having wire windings. An identifier circuit is connected to the identifier antenna for receiving the power signal and for transmitting a unique identifier signal.

Claims

1. A proximity identification system comprising:

a reader section having a reader circuit connected to a reader antenna, said reader circuit for supplying a power signal and for detecting an identifier signal, said reader antenna for inductively coupling with an identifier antenna for transmitting said power signal to said identifier antenna and for receiving said identifier signal from said identifier antenna, said reader antenna comprised of a ferromagnetic rod having wire windings; and

an identifier section having an identifier circuit connected to an identifier antenna, said identifier circuit for generating said identifier signal responsive to said power signal.

2. The system of claim 1 wherein,

said identifier antenna is comprised of a ferromagnetic rod having wire windings.

3. The system of claim 2 wherein,

said identifier antenna further comprises a metal plate connected to said rod by means of insulating brackets.

4. The system of claim 1 wherein,

said reader antenna further comprises a metal plate connected to said rod by means of insulating brackets.

5. The system of claim 1 wherein,

said reader circuit further comprises an oscillator connected to said reader antenna for providing said electrical power and a transformer connected to said oscillator and said reader antenna for subtracting said electrical power signal from said identifier signal.

6. The system of claim 1 wherein,

said wire windings are concentrated proximate both end portions of said ferromagnetic rod.

7. The system of claim 1 wherein,

said ferromagnetic rod has a primary wire winding and a secondary wire winding.

8. The system of claim 1 wherein,

said reader antenna comprises a plurality of ferromagnetic rods having wire windings, each of said ferromagnetic rods having a longitudinal axis and each ferromagnetic rod being oriented with parallel axis.

9. The system of claim 1 wherein,

said reader antenna further comprises a dipole antenna and said identifier antenna further comprises a dipole antenna.

10. The system of claim 9 wherein,

said identifier dipole antenna comprises a vehicle chassis.

11. The system of claim 1 wherein,

said identifier antenna is attached to a vehicle license plate.

12. The system of claim 1 wherein,

the identifier section is attached to an animal to be identified.

13. The system of claim 1 wherein,

the identifier section is mounted in a card, said identifier antenna is a loop antenna, and the identifier section is mounted at the end of a ferromagnetic rod attached to a vehicle.

14. The system of claim 1 wherein,

the identifier section is mounted in a housing, said identifier antenna is comprised of wire turns, and said housing is shaped to fit around a ferromagnetic rod attached to a vehicle.

15. A proximity identification system comprising:

a reader section comprising an oscillator for providing a power signal, a reader antenna connected to said oscillator comprised of a ferromagnetic rod having wire windings for inductively coupling with an identifier antenna for radiating said power signal to said identifier antenna and for receiving an identifier signal from said identifier antenna, a recognition means connected to said reader antenna for recognizing said identifier signal; and

an identifier section comprising an identifier antenna for receiving said power signal and radiating said identifier signal, said identifier antenna comprised of a ferromagnetic rod having wire windings, and an identifier circuit connected to said identifier antenna for providing said identifier signal responsive to said power signal.

16. The system of claim 15 wherein,

said recognition means comprises a transformer connected to said oscillator and said reader antenna for subtracting said power signal from said identifier signal.

17. The system of claim 15 wherein,

said wire windings of said reader antenna are concentrated proximate both end portions of said ferromagnetic rod.

18. The system of claim 15 wherein,

said ferromagnetic rod of said reader antenna has a primary wire winding and a secondary wire winding.

19. The system of claim 15 wherein,

said reader antenna is comprised of a plurality of ferromagnetic rods each having its own set of wire windings, each ferromagnetic rod having a longitudinal axis, all ferromagnetic rods oriented with their longitudinal axis parallel.

20. The system of claim 19 wherein,

said reader antennas are mounted proximate a vehicle path and said identifier section is mounted to a vehicle.

21. The system of claim 19 wherein,

said reader antennas are mounted within a passageway and said identifier section is mounted to a badge.

22. The system of claim 15 wherein,

said reader antenna further comprises a dipole antenna and said identifier antenna further comprises a dipole antenna.

23. The system of claim 22 wherein,

said identifier dipole antenna comprises a vehicle chassis.

24. The system of claim 15 wherein,

said identifier antenna is attached to a vehicle license plate.

25. The system of claim 15 wherein,

the identifier section is attached to an animal to be identified.

26. A proximity identificaticn system comprising:

a reader section comprising an oscillator for providing a power signal, a reader antenna connected to said oscillator comprised of a ferromagnetic rod having wire windings for inductively coupling with an identifier antenna for radiating said power signal to said identifier antenna and for receiving an identifier signal from said identifier antenna, a recognition means connected to said reader antenna for recognizing said identifier signal and;

an identifier section comprising an identifier antenna for receiving said power signal and radiating said identifier signal, said identifier antenna is a loop antenna, and an identifier circuit connected to said identifier antenna for providing said identifier signal responsive to said power signal.

27. The system of claim 26 wherein,

said recognition means comprises a transformer connected to said oscillator and said reader antenna for subtracting said power signal from said identifier signal.

28. The system of claim 26 wherein,

said reader antenna is comprised of a plurality of ferromagnetic rods each having its own set of wire windings, each ferromagnetic rod having a longitudinal axis, all ferromagnetic rods oriented with their longitudinal axis parallel.

29. The system of claim 26 wherein,

said reader antennas are mounted proximate a vehicle path and said identifier section is mounted to a vehicle.

30. The system of claim 26 wherein,

said reader antennas are mounted within a passageway and said identifier section is mounted to a badge.

31. A proximity identification system comprising:

a reader section having an oscillator for providing a power signal, a plurality of amplifiers connected to said oscillator, a plurality of reader antennas for inductively coupling with an identifier antenna for radiating said power signal to said identifier antenna and for receiving an identifier signal from said identifier antenna, each reader antenna connected to one of said amplifiers, said reader antenna each comprised of a ferromagnetic rod having wire windings, a plurality recognition means, each connected to one of said reader antennas for recognizing said identifier signal received by the reader antenna to which that recognition means is connected and a plurality of memory storage means, each memory storage means connected to one of said recognition means for storing information contained in said identifier signal recognized by the recognition means to which that memory storage means is connected; and

an identifier section comprising an identifier circuit connected to an identifier antenna, said identifier circuit for providing said identifier signal responsive to said power signal.