Space-filling miniature antennas

• US 8,558,741 B2
• Filed: 03/09/2011
• Issued: 10/15/2013
• Est. Priority Date: 01/19/2000
• Status: Expired due to Fees

• Current Assignee: Fractus SA
• Original Assignee: Fractus SA
• Inventors: Baliarda, Carles Puente, Rozan, Edouard Jean Louis, Pros, Jaime Anguera
• Primary Examiner(s): Nguyen, Hoang V
• Application Number:
  US13/044,207
• Publication Number:
  US 20110177839A1
• Time in Patent Office: 951 Days
• Field of Search: 343/700.MS, 343/702, 343/895
• US Class Current: 343/700.MS
• CPC Class Codes: H01Q 1/36 Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewithH01Q1/08, H01Q1/14 take precedence
• 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 13/10 Resonant slot antennas
• CPC Class Codes: H01Q 5/25 Ultra-wideband [UWB] systems, e.g. multiple resonance systems; Pulse systems
• CPC Class Codes: H01Q 5/357 using a single feed point
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40
• CPC Class Codes: H01Q 9/40 Element having extended radiating surface
• CPC Class Codes: H01Q 9/42 with folded element, the folded parts being spaced apart a small fraction of the operating wavelength

Abstract

A novel geometry, the geometry of Space-Filling Curves (SFC) is defined in the present invention and it is used to shape a part of an antenna. By means of this novel technique, the size of the antenna can be reduced with respect to prior art, or alternatively, given a fixed size the antenna can operate at a lower frequency with respect to a conventional antenna of the same size.

Claims

1. An apparatus comprising:

a portable communication device, wherein said portable communication device is a handset;

at least a first single antenna, the first single antenna being included entirely within the handset;

said first single antenna operates at multiple frequency bands, and

wherein at least two of said frequency bands are non-overlapping cellular telephone system frequency bands within the 800 MHz-3600 MHz frequency range;

said first single antenna comprising an element that radiates and receives electromagnetic waves, the element having a perimeter that is shaped as a multi-segment, irregular curve;

said multi-segment, irregular curve comprises at least ten connected segments, each segment is shorter than one tenth of at least one operating free-space wavelength of the antenna;

said multi-segment, irregular curve is shaped so that an arrangement of the segments of the multi-segment, irregular curve are not self-similar with respect to the entire multi-segment, irregular curve; and

the first single antenna simultaneously receives electromagnetic waves within at least two of the frequency bands in the 800MHz-3600MHz frequency range.

2. The apparatus of claim 1, wherein the first single antenna radiates at least at two different operating wavelengths, wherein at least one of said operating wavelengths corresponds to an operating wavelength of a GSM 900 cellular telephone system or a GSM 1800 cellular telephone system.

3. The apparatus of claim 2, wherein the first single antenna is a monopole antenna comprising a radiating arm and a ground counterpoise, the element being the radiating arm.

4. The apparatus of claim 2, wherein a box-counting dimension of the multi-segment, irregular curve is greater than or equal to 1.2, the box-counting dimension is computed as the slope of a substantially straight portion of a line in a log-log graph over at least an octave of scales on the horizontal axes of the log-log graph.

5. The apparatus of claim 1, wherein a box-counting dimension of the multi-segment, irregular curve is greater than 1.3, the box-counting dimension is computed as the slope of a substantially straight portion of a line in a log-log graph over at least an octave of scales on the horizontal axes of the log-log graph.

6. The apparatus of claim 5, wherein the first single antenna comprises a network between the element and an input connector or transmission line, said network being a matching network.

7. The apparatus of claim 6, wherein at least one of said multiple frequency bands is within a requency range selected from the group consisting of GSM frequencies.

8. The apparatus of claim 6, wherein the multi-segment, irregular curve lies on a curved surface.

9. The apparatus of claim 8, wherein the multi-segment, irregular curve extends across a surface lying in more than one plane.

10. The apparatus of claim 8, wherein said multi-segment, irregular curve includes at least 25 bends.

11. The apparatus of claim 1, wherein the multi-segment, irregular curve lies on a curved surface.

12. The apparatus of claim 1, wherein the first single antenna comprises a network between the element and an input connector or transmission line, said network being a matching network.

13. The apparatus of claim 12, wherein the first single antenna comprises multiple electromagnetically coupled radiating elements.

14. The apparatus of claim 1, wherein the first single antenna comprises:

a ground plane;

the element acting in cooperation with the ground plane;

the element comprises a slot therein a perimeter of the slot forming at least a part of the multi-segment, curve; and

a portion of said multi-segment, irregular curve comprises at least 10 bends.

15. The apparatus of claim 14, wherein the first single antenna is a patch antenna, and wherein the element is a conducing patch substantially parallel to the ground plane.

16. The apparatus of claim 14, wherein the first single antenna radiates at least at two different operating wavelengths, wherein at least one of said operating wavelengths corresponds to an operating wavelength of a GSM 900 cellular telephone system or a GSM 1800 cellular telephone system.

17. The apparatus of claim 1, wherein a box-counting dimension of the multi-segment, irregular curve is greater than 1.4, the box-counting dimension is computed as the slope of a substantially straight portion of a line in a log-log graph over at least an octave of scales on the horizontal axes of the log-log graph.

18. The apparatus of claim 17, wherein the first single antenna radiates at least at two different operating wavelengths, wherein at least one of said operating wavelengths corresponds to an operating wavelength of a GSM 900 cellular telephone system or a GSM 1800 cellular telephone system.

19. The apparatus of claim 1, wherein a box-counting dimension of the multi-segment, irregular curve is greater than or equal to 1.5, the box-counting dimension is computed as the slope of a substantially straight portion of a line in a log-log graph over at least an octave of scales on the horizontal axes of the log-log graph.

20. The apparatus of claim 19, wherein the first single antenna radiates at least at two different operating wavelengths, wherein at least one of said operating wavelengths corresponds to an operating wavelength of a GSM 900 cellular telephone system or a GSM 1800 cellular telephone system.

21. An apparatus comprising:

a portable communication device, wherein said portable communication device is a handset;

at least a first single antenna, the first single antenna being included entirely within the handset;

said first single antenna operates at multiple frequency bands, and wherein at least two of said multiple frequency bands are within the 800 MHz-3600 MHz frequency range;

said first single antenna comprising an element that radiates and receives electromagnetic waves, the element having an edge that is shaped as a substantially non- periodic multi-segment curve;

said substantially non-periodic multi-segment curve comprises at least ten connected segments, each segment is shorter than one tenth of at least one operating free- space wavelength of the antenna;

the first single antenna comprising a matching network between the element and an input connector or transmission line; and

the first single antenna simultaneously receives electromagnetic waves of at least a first and a second operating wavelength, each of the first and second operating wavelengths being respectively within a first and a second non-overlapping cellular telephone system frequency bands of the multiple frequency bands.

22. The apparatus of claim 21, wherein the first single antenna radiates at least at two different operating wavelengths, wherein at least one of said operating wavelengths corresponds to an operating wavelength of a GSM 900 cellular telephone system or a GSM 1800 cellular telephone system.

23. The apparatus of claim 22, wherein the substantially non-periodic multi-segment curve lies on a curved surface.

24. The apparatus of claim 21, wherein a box-counting dimension of the substantially non-periodic multi-segment curve is greater than 1.3, the box-counting dimension is computed as the slope of a substantially straight portion of a line in a log-log graph over at least an octave of scales on the horizontal axes of the log-log graph.

25. The apparatus of claim 24, wherein the cellular telephone system is a GSM 900 system or a GSM 1800 system.

26. The apparatus of claim 21, wherein a box-counting dimension of the substantially non-periodic multi-segment curve is greater than 1.4, the box-counting dimension is computed as the slope of a substantially straight portion of a line in a log-log graph over at least an octave of scales on the horizontal axes of the log-log graph.

27. The apparatus of claim 26, wherein the first single antenna is a monopole antenna comprising a radiating arm and a ground counterpoise, the element being the radiating arm.

28. The apparatus of claim 27, wherein the cellular telephone system is a GSM 900 system or a GSM 1800 system.

29. The apparatus of claim 21, wherein a box-counting dimension of the substantially non-periodic multi-segment curve is greater than 1.5, the box-counting dimension is computed as the slope of a substantially straight portion of a line in a log-log graph over at least an octave of scales on the horizontal axes of the log-log graph.

30. The apparatus of claim 29, wherein the first single antenna is a patch antenna comprising:

a ground plane; and

a conducting patch substantially parallel to a ground plane, the element being the conducting patch.

31. The apparatus of claim 21, wherein the element has a slot therein an edge of the slot forming at least a part of the substantially non-periodic multi-segment curve, wherein said substantially non-periodic multi-segment curve includes at least 10 bends.

32. The apparatus of claim 31, wherein the first single antenna radiates at least at two different operating wavelengths, wherein at least one of said operating wavelengths corresponds to an operating wavelength of a GSM 900 cellular telephone system or a GSM 1800 cellular telephone system.

33. The apparatus of claim 32, wherein the substantially non-periodic multi-segment curve extends across a surface lying in more than one plane.

34. The apparatus of claim 31, wherein at least one of said non-overlapping cellular telephone system frequency bands is within a frequency range of GSM frequencies.

35. The apparatus of claim 34, wherein said substantially non-periodic multi-segment curve includes at least 25 bends.

36. The apparatus of claim 31, wherein a box-counting dimension of the substantially non-periodic multi-segment curve is greater than or equal to 1.2, the box-counting dimension is computed as the slope of a substantially straight portion of a line in a log-log graph over at least an octave of scales on the horizontal axes of the log-log graph.

37. The apparatus of claim 36, wherein the first single antenna radiates at least at two different operating wavelengths, wherein at least one of said operating wavelengths corresponds to an operating wavelength of a GSM 900 cellular telephone system or a GSM 1800 cellular telephone system.

38. The apparatus of claim 37, wherein the substantially non-periodic multi-segment curve lies on a curved surface.

39. The apparatus of claim 21, wherein the substantially non-periodic multi-segment curve extends across a surface lying in more than one plane.

40. The apparatus of claim 39, wherein the first single antenna radiates at least at two different operating wavelengths, wherein at least one of said operating wavelengths corresponds to an operating wavelength of a GSM 900 cellular telephone system or a GSM 1800 cellular telephone system.

41. The apparatus of claim 40, wherein a box-counting dimension of the substantially non-periodic multi-segment curve is greater than or equal to 1.2, the box-counting dimension is computed as the slope of a substantially straight portion of a line in a log-log graph over at least an octave of scales on the horizontal axes of the log-log graph.

42. The apparatus of claim 21, wherein the first single antenna comprises multiple electromagnetically coupled radiating elements.

43. An apparatus comprising:

a portable communication device, the portable communication device being a handset;

at least a first single antenna, the first single antenna being included entirely within the handset;

said first single antenna operates at multiple frequency bands;

at least two of said multiple frequency bands are within the 800 MHz-3600 MHz frequency range and the at least two of said multiple frequency bands are non-overlapping frequency bands;

the first single antenna comprises a radiating element, a perimeter of which is defined by a multi-segment, irregular curve comprising a plurality of segments, each of said segments being spatially arranged such that no two adjacent and connected segments form another longer straight segment and none of said segments intersects with another segment other than at the beginning and at the end of said multi-segment, irregular curve to form a closed loop;

each segment of said plurality of segments is shorter than one tenth of a longest operating free-space wavelength of said multiple frequency bands; and

the multi-segment, irregular curve has a box counting dimension larger than one with the box-counting dimension computed as the slope of a substantially straight portion of a line in a log-log graph over at least one octave of scales on a horizontal axis of the log-log graph.

44. The apparatus of claim 43, wherein the first single antenna radiates at least at two different operating wavelengths, and wherein at least one of said operating wavelengths corresponds to an operating wavelength of a cellular telephone system.

45. The apparatus of claim 44, wherein the box-counting dimension of the multi-segment, irregular curve is greater than 1.3.

46. The apparatus of claim 44, wherein the multi-segment, irregular curve lies on a curved surface.

47. The apparatus of claim 44, wherein the first single antenna comprises a network between the radiating element and an input connector or transmission line, said network being a matching network.

48. The apparatus of claim 44, wherein the first single antenna is a monopole antenna comprising a radiating arm and a ground counterpoise, the radiating element being the radiating arm.

49. The apparatus of claim 48, wherein the first single antenna comprises multiple electromagnetically coupled radiating elements.

50. The apparatus of claim 49, wherein said first single antenna operates at multiple frequency bands, and wherein at least one of said frequency bands is within a frequency range of GSM frequencies.

51. The apparatus of claim 49, wherein the box-counting dimension of the multi-segment, irregular curve is greater than or equal to 1.2.

52. The apparatus of claim 49, wherein the multi-segment, irregular curve lies on a curved surface.

53. The apparatus of claim 44, wherein the first single antenna comprises a network between the radiating element and an input connector or transmission line, said network being a matching network.

54. The apparatus of claim 53, wherein the multi-segment, irregular curve extends across a surface lying in more than one plane.

55. The apparatus of claim 54, wherein the first single antenna radiates at least at two different operating wavelengths, wherein at least one of said operating wavelengths corresponds to an operating wavelength of a GSM 900 cellular telephone system or a GSM 1800 cellular telephone system.

56. The apparatus of claim 53, wherein said multi-segment, irregular curve includes at least 25 bends.

57. The apparatus of claim 43, wherein the first single antenna comprises:

a ground plane;

the radiating element acting in cooperation with the ground plane;

the radiating element comprising a slot therein, a perimeter of the slot forming at least a part of the multi-segment, irregular curve; and

said multi-segment, irregular curve includes at least 10 bends.

58. The apparatus of claim 57, wherein the first single antenna is a patch antenna, and wherein the radiating element is a conducting patch substantially parallel to the ground plane.

59. The apparatus of claim 43, wherein the box-counting dimension of the multi-segment, irregular curve is greater than 1.4.

60. The apparatus of claim 59, wherein the first single antenna radiates at least at two different operating wavelengths, and wherein at least one of said operating wavelengths corresponds to an operating wavelength of a cellular telephone system.

61. The apparatus of claim 43, wherein the box-counting dimension of the multi-segment, irregular curve is greater than 1.5.