Antenna array for smart RFID tags

• US 6,696,954 B2
• Filed: 05/14/2001
• Issued: 02/24/2004
• Est. Priority Date: 10/16/2000
• Status: Expired due to Term

• Current Assignee: Avante International Technology
• Original Assignee: Amerasia International Technology, Inc.
• Inventors: Chung, Kevin Kwong-Tai
• Primary Examiner(s): Wu, Daniel J.
• Assistant Examiner(s): Nguyen, Tai T.
• Application Number:
  US09/854,722
• Publication Number:
  US 20020044096A1
• Time in Patent Office: 1,016 Days
• Field of Search: 340/572.7, 340/551, 340/572.1, 340/552, 340/745, 340/748, 340/893, 340/894, 340/866, 340/867, 343/894
• US Class Current: 340/572.7
• CPC Class Codes: G06K 7/10336 the antenna being of the near field type, inductive coil
• CPC Class Codes: G06K 7/10346 the antenna being of the far field type, e.g. HF types or dipoles
• CPC Class Codes: G08B 13/2417 having a radio frequency identification chip
• CPC Class Codes: G08B 13/2462 Asset location systems combined with EAS inventory, tracking, logistic G06Q10/00; entrance control systems G07C9/00
• CPC Class Codes: G08B 13/2471 Antenna signal processing by receiver or emitter
• CPC Class Codes: G08B 13/2474 Antenna or antenna activator geometry, arrangement or layout loop antennae H01Q1/22
• CPC Class Codes: G08B 13/2477 Antenna or antenna activator circuit
• CPC Class Codes: G08B 13/2482 EAS methods, e.g. description of flow chart of the detection procedure
• CPC Class Codes: H01Q 1/2216 used in interrogator/reader equipment
• 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 21/24 Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction circularly polarised patch antennas H01Q9/0428; circularly polarised horns H01Q13/0241; cross-polarised horns H01Q13/0258; polarisation converters H01Q15/242; cross-polarised rear feeds H01Q19/136; crossed polarisation dual antenna H01Q25/001
• CPC Class Codes: H01Q 21/29 Combinations of different interacting antenna units for giving a desired directional characteristic H01Q25/00 takes precedence
• 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

Abstract

An antenna array comprises a plurality of antenna loops disposed to define a portal or passageway or other detection region in which the plural antenna loops transmit and/or receive electromagnetic signals. A processor coupled to the plural antenna loops processes at least the received signals and/or transmitted signals. The plural antennas may be arrayed in a rectangular array, on hanging flexible substrates or other suitable arrangement, and may be coupled to the processor by a filter or selective switch. The processor may be coupled to a utilization system for cooperating therewith for performing a desired function.

Claims

1. An antenna array for detecting a wireless article associated with an object comprising:

a plurality of flexible substrates each defining peripheral edges;

a plurality of antenna loops each disposed on one of the flexible substrates, wherein the flexible substrates are adapted to be hung to define a detection region in which said plurality of antenna loops transmit and receive electromagnetic signals and through which nix the object and associated wireless tag may pass, wherein each antenna loop includes a single turn of a strip conductor disposed on the flexible substrate along the peripheral edges thereof, and wherein each antenna loop transmits and receives electromagnetic signals;

a processor for causing electromagnetic signals to be transmitted and for processing at least received signals for detecting the wireless article associated with the object; and

means coupling said plurality of antenna loops and said processor for coupling at least the transmitted and received signals therebetween.

2. The antenna array of claim 1 wherein said plurality of flexible substrates are elongated and are hung substantially edge-to-edge from a top of a passageway through which an object may pass.

3. The antenna array of claim 2 wherein said plurality of flexible substrates substantially cover the passageway, and wherein said plurality of antenna loops disposed on said plurality of flexible substrates are adapted to transmit and receive electromagnetic signals to a wireless article proximate the passageway.

4. The antenna array of claim 1 wherein said means for coupling includes at least one of a filter and a switch for selectively connecting said plurality of antenna loops and said processor.

5. The antenna array of claim 1 wherein said processor processes transmitted signals and said received signals, wherein said transmitted signals are coupled to said plurality of antenna loops to be transmitted thereby.

6. The antenna array of claim 5 in combination with a wireless article adapted to be associated with an object, said wireless article including a ioop antenna and an electronic device including a memory, wherein said processor processes transmitted signals of a type adapted to be received by the electronic device via the loop antenna and processes received signals of a type adapted to be produced by the electronic device.

7. The antenna array of claim 6 wherein the signals received by the electronic device one of activate, operate, or control the electronic device and cause storing of information in the memory or reading of information from the memory.

8. The antenna array of claim 1 in combination with:

an additional antenna loop disposed at an angle with respect to said plurality of antenna loops to further define the detection region in which said plurality of antenna loops and said additional antenna loop transmit and/or receive electromagnetic signals, wherein said additional antenna loop defines a loop through which an object may pass; and

means coupling said additional antenna loop and said processor for coupling at least the received signals therebetween.

9. The antenna array of claim 8 wherein said additional antenna loop is disposed at an angle of between about 45°

and about 135°

with respect to said plurality of antenna loops.

10. The antenna array of claim 1 in combination with a wireless article adapted to be associated with an object, said wireless article including a loop antenna and an electronic device including a memory, wherein said processor processes received signals of a type adapted to be produced by the electronic device.

11. The antenna array of claim 1 in combination with a utilization system operable in conjunction with the transmitted signals and the received signals.

12. The antenna array of claim 1 wherein said utilization system includes one of toll collection, object identification, stolen object identification, theft prevention, object tracking, package tracking, baggage tacking, retailing, inventory tracking, factory and/or warehouse inventory, security identification, and/or access control.

13. The antenna array of claim 1 wherein said detection region includes at least one of a portal, a passage, a passageway, a doorway, an access, an egress, a security gate, a toll gate, an electronic gate, a retail check-out station, a corridor, a tunnel, a conveyor, a baggage cart, an enclosure, a storage space, a container, a shipping container, a pallet, a cargo bay, a truck, a trailer, a loading area, and a warehouse.

14. One of a plurality of flexible antenna for detecting a wireless article associated with an object comprising an elongated flexible substrate adapted to be suspended from one end thereof and having opposing broad surfaces defining peripheral edges, a strip of electrically conductive material disposed on at least one of the broad surfaces proximate-the-periphery along the peripheral edges of said flexible substrate to define a single-turn loop, and a coupler to which respective ends of said strip of electrically conductive material are coupled for transmitting and receiving electromagnetic signals, wherein the flexible antenna flexes when contacted by the object.

15. The antenna of claim 14 wherein said elongated flexible substrate comprises two sheets of a flexible material, and wherein said strip of electrically conductive material is laminated between said two sheets of flexible material.

16. The antenna of claim 14 wherein said strip of conductive material includes one of copper, aluminum and electrically-conductive flexible adhesive.

17. An antenna array for detecting a wireless article associated with an object comprising:

a plurality of elongated flexible substrates each having opposing broad surfaces defining peripheral edges, wherein the flexible substrates are adapted to be suspended from one end thereof to define a detection region;

on given ones of said flexible substrates, a strip of electrically conductive material disposed on at least one of the broad surfaces of the given ones of said flexible substrate along the peripheral edges thereof to define a single-turn loop;

associated with the given ones of said flexible substrates, a coupler to which respective ends of said strip of electrically conductive material on the given one of said flexible substrate are coupled;

thereby providing a plurality of single-turn antenna loops disposed on the given ones of said flexible substrates in the detection region in which each of said plurality of single-turn antenna loops transmit and receive electromagnetic signals;

a processor for processing at least received signals for detecting the wireless article associated with the object; and

means coupling the couplers of said plurality of antenna loops and said processor for coupling at least the received signals therebetween.

18. The antenna array of claim 17 wherein said plurality of flexible substrates are elongated and are hung substantially edge-to-edge from a top of a passageway.

19. The antenna array of claim 17 wherein each of the given ones of said elongated flexible substrate comprises two sheets of a flexible material, and wherein said strip of electrically conductive material is laminated between said two sheets of flexible material.

20. The antenna array of claim 17 comprising:

on at least one of the given ones of said flexible substrates, a second strip of electrically conductive material disposed on at least one of the broad surfaces of the at least one of the given ones of said flexible substrate proximate the periphery thereof to define a second loop, wherein respective ends of said second strip of electrically conductive material on the at least one of the given ones of said flexible substrate are coupled to said coupler associated therewith.

21. The antenna array of claim 17 in combination with:

an additional antenna loop disposed at an angle with respect to said at least two antenna loops to further define the detection region in which said two antenna loops and said additional antenna loop transmit and/or receive electromagnetic signals, wherein said additional antenna loop defines a loop through which an object may pass; and

means coupling said additional antenna loop and said processor for coupling at least the received signals therebetween.

22. The antenna array of claim 21 wherein said additional antenna loop is disposed at an angle of between about 45°

and about 135°

with respect to said two antenna loops.

23. The antenna array of claim 17 in combination with a utilization system operable in conjunction with the transmitted signals and the received signals.

24. The antenna array of claim 17 wherein said utilization system includes one of toll collection, object identification, stolen object identification, theft prevention, object tracking, package tracking, baggage tracking, retailing, inventory tracking, factory and/or warehouse inventory, security identification, and/or access control.

25. The antenna array of claim 17 wherein said detection region includes at least one of a portal, a passage, a passageway, a doorway, an access, an egress, a security gate, a toll gate, an electronic gate, a retail check-out station, a corridor, a tunnel, a conveyor, a baggage cart, an enclosure, a storage space, a container, a shipping container, a pallet, a cargo bay, a truck, a trailer, a loading area, and a warehouse.

26. An antenna array for detecting a wireless article associated with an object comprising:

at least two loop antennas disposed at an angle with respect to each other to define a detection region in which each of said two loop antennas transmit and/or receive electrical signals,

wherein an electromagnetic field associated with the electrical signals has components in each of three mutually orthogonal directions,

the detection region thereby defined having a volume into which and/or through which the object and its associated wireless article may pass;

each of said two loop antennas including a loop conductor arranged to crossover to form two loops of smaller dimension than the loop antenna, each smaller loop of each antenna being in a different plane than the other smaller loop of that loop antenna;

wherein the two smaller loops of each loop antenna are disposed respectively in two planes disposed at an angle of between about 45° and

about 135°

with respect to each other;

whereby the loon conductor of each loon antenna defines two loons each in a different plane, for a total of four loops in four different planes,

a processor for processing at least received electrical signals for detecting the wireless article associated with the object; and

means for coupling at least the received electrical signals between said at least two loop antennas and said processor.

27. The antenna array of claim 26 further comprising a third loop antenna having a loop conductor disposed so that an object to be detected passes therethrough.

28. The antenna may of claim 26 wherein said means for coupling includes at least one of a filter and a switch for selectively connecting said at least two loop antennas and said processor.

29. The antenna array of claim 26 wherein said processor processes transmitted electrical signals and the received electrical signals, wherein the transmitted electrical signals are coupled to said at least two loop antennas to be transmitted thereby.

30. The antenna ray of claim 26 in combination with a wireless article including an antenna coupled to an electronic device including a memory, wherein said processor processes transmitted electrical signals receivable by the electronic device via the antenna of said wireless article and processes received electrical signals produced by the electronic device.

31. The antenna array of claim 26 in combination with a utilization system operable in conjunction with the transmitted electrical signals and the received electrical signals.

32. The antenna array of claim 31 wherein said utilization system includes one of toll collection, object identification, stolen object identification, theft prevention, object tracking, package tracking, baggage tracking, retailing, inventory tracking, factory and/or warehouse inventory, security identification, and access control.

33. The antenna array of claim 26 wherein said detection region includes at least one of a portal, a passage, a passageway, a doorway, an access, an egress, a security gate, a toll gate, an electronic gate, a retail cheek-out station, a corridor, a tunnel, a conveyor, a baggage cart, an enclosure, a storage space, a container, a shipping container, a pallet, a cargo bay, a truck, a trailer, a loading area, and a warehouse.

34. A detection arrangement for detecting a wireless article associated with an object within a detection region, wherein the detection region is defined with respect to three mutually orthogonal directions X, Y and Z, wherein the three mutually orthogonal directions define three mutually orthogonal planes X-Y, X-Z and Y-Z, the detection arrangement comprising:

a first loop antenna having a loop conductor disposed substantially in the X-Y plane, wherein the first loop antenna transmits and/or receives electrical signals related to an associated electromagnetic field in the detection region;

a second loop antenna having a loop conductor disposed substantially in a plane rotated about the X direction to be at an angle with respect to the X-Y plane, wherein the second loop antenna transmits and/or receives electrical signals related to an associated electromagnetic field in the detection region;

a third loop antenna having a loop conductor disposed substantially in a plane rotated about the Y direction to be at an angle with respect to the X-Y plane, wherein the third loop antenna transmits and/or receives electrical signals related to an associated electromagnetic field in the detection region;

wherein if the object and its associated wireless article pass through the detection region, then to object and its associated wireless article pass through each of said first, second and third loon antenna;

whereby each of said first, second and third loop antenna produces an electromagnetic field into detection region if transmitting electrical signals and responds to an electromagnetic field in the detection region if receiving electrical signals, the electromagnetic fields associated with said first, second and third loop antenna together having field components m each of three mutually orthogonal directions,

a processor for processing at least received electrical signals for detecting the wireless article associated with the object; and

means for coupling at least the received electrical signals between said first, second and third loop antenna and said processor.

35. The detection arrangement of claim 34 wherein said means for coupling includes at least one of a filter and a switch for selectively connecting said first, second and third loop antenna and said processor.

36. The detection arrangement of claim 34 wherein said processor processes transmitted electrical signals and received electrical signals,

wherein the transmitted electrical signals are coupled to said first second and third loop antenna to be transmitted thereby.

37. The detection arrangement of claim 34 in combination with an object comprising a wireless article including an antenna coupled to an electronic device including a memory, wherein said processor processes transmitted electrical signals receivable by the electronic device via the antenna of said wireless article and processes received electrical signals produced by the electronic device.

38. The detection arrangement of claim 37 wherein electrical signals received by the electronic device one of activate, operate, or control the electronic device and cause storing of information in the memory or reading of information from the memory.

39. The detection arrangement of claim 34 in combination with a wireless article including an antenna coupled to an electronic device including a memory,

wherein said processor processes received electrical signals produced by the electronic device.

40. The detection arrangement of claim 34 further comprising:

at least one additional loop antenna disposed substantially in one of the X-Z and Y-Z planes proximate the detection region,

wherein said at least one additional loop antenna transmits and/or receives electrical signals related to an associated electromagnetic field in the detection region; and

means coupling said additional loop antenna and said processor for coupling at least the received electrical signals therebetween.

41. The detection arrangement of claim 34 further comprising:

at least two additional loop antenna disposed generally parallel to each other and disposed at opposite sides of the detection region,

wherein said two additional loop antenna transmit and/or receive electrical signals related to an associated electromagnetic field in the detection region; and

means coupling said at least two additional loop antenna and said processor for coupling at least the received electrical signals therebetween.

42. The detection arrangement of claim 34 in combination with a utilization system operable in conjunction with the transmitted electrical signals and the received electrical signals.

43. The detection arrangement of claim 42 wherein said utilization system includes one of toll collection, object identification, stolen object identification, theft prevention, object tracking, package tracking, baggage tracking, retailing, inventory tracking, factory and/or warehouse inventory, security identification, and access control.

44. The detection arrangement of claim 34 wherein said detection region includes at least one of a portal, a passage, a passageway, a doorway, an access, an egress, a security gate, a toll gate, an electronic gate, a retail check-out station, a corridor, a tunnel, a conveyor, a baggage cart, an enclosure, a storage space, a container, a shipping container, a pallet, a cargo bay, a truck, a trailer, a loading area, and a warehouse.

54. The antenna array of claim 43 wherein the detection region includes at least one of a portal, a passage, a passageway, a doorway, an access, an egress, a security gate, a toll gate, an electronic gate, a retail check-out station, a corridor, a tunnel, a conveyor, a baggage cart, an enclosure, a storage space, a container, a shipping container, a pallet a cargo bay, a truck, a trailer, a loading area, and a warehouse.

45. An antenna array for detecting an object within a detection region comprising:

at least two antenna loops disposed at an angle with respect to each other to transmit and/or receive electrical signals via an associated electromagnetic field having a component in each of three mutually orthogonal directions in the detection region into which or through which an object may pass;

a processor for processing at least received electrical signals for detecting the object;

means selectively coupling said at least two antenna loops and said processor,

wherein said means for selectively coupling alternatingly or sequentially couples at least the received electrical signals of said at least two antenna loops to said processor during a tine that the object is within the detection region, and

wherein the received electrical signals of said at least two antenna loops are coupled alternatingly or sequentially to said processor;

an additional antenna loop disposed at an angle with respect to said at least two antenna loops to transmit and/or receive electrical signals in the detection region, wherein said additional antenna loop defines a loop through which the object may pass; and

wherein said means for selectively coupling couples at least received electrical signals of said additional antenna loop to said processor during the time that the object is within the detection region, and

wherein the received electrical signals of said additional antenna loop are coupled alternatingly or sequentially with the received electrical signals of the at least two antenna loops.

46. The antenna array of claim 45 wherein the angle at which said two antenna loops are disposed is between about 45°

and about 135°

.

47. The antenna array of claim 45 wherein said processor processes transmitted electrical signals and the received electrical signals, wherein the transmitted electrical signals are coupled to said two antenna loops to be transmitted thereby.

48. The antenna array of claim 47 in combination with a wireless article including an antenna coupled to an electronic device including a memory, wherein said processor processes transmitted electrical signals receivable by the electronic device via the loop antenna and processes received electrical signals produced by the electronic device.

49. The antenna array of claim 48 wherein the electrical signals received by the electronic device one of activate, operate, or control the electronic device and cause storing of information in the memory or reading of information from the memory.

50. The antenna array of claim 45 in combination with a wireless article including a loop antenna coupled to an electronic device including a memory, wherein said processor processes received electrical signals produced by the electronic device.

51. The antenna array of claim 45 wherein said additional antenna loop is disposed at an angle of between about 45°

and about 135°

with respect to said two antenna loops.

52. The antenna may of claim 45 in combination with a utilization system operable in conjunction with the transmitted electrical signals and the received electrical signals.

53. The antenna array of claim 52 wherein said utilization system includes one of toll collection, object identification, stolen object identification, theft prevention, object tracking, package tracking, baggage tracking, retailing, inventory tracking, factory and/or warehouse inventory, security identification, and access control.

55. An antenna array for detecting an object within a detection region comprising:

at least two antenna loops disposed at an angle with respect to each other to transmit and/or receive electrical signals via an associated electromagnetic field having a component in each of three mutually orthogonal directions in the detection region into which or through which an object may pass;

a processor for processing at least received electrical signals for detecting the object;

means selectively coupling said at least two antenna loops and said processor,

wherein said means for selectively coupling alternatingly or sequentially couples at least the received electrical signals of said at least two antenna loops to said processor during a time that the object is within the detection region, and

wherein the received electrical signals of said at least two antenna loops are coupled alternatingly or sequentially to said processor;

at least two additional antenna loops disposed at an angle with respect to each other and disposed opposing said at least two antenna loops to transmit and/or receive electrical signals in the detection region; and

wherein said means for selectively coupling couples at least received electrical signals of said two additional antenna loops to said processor during the time that the object is within the detection region, and

wherein the received electrical signals of said two additional antenna loops are coupled alternatingly or sequentially with the received electrical signals of the at least two antenna loops.