Antenna Diversity System and Slot Antenna Component

• US 20080198082A1
• Filed: 05/12/2006
• Published: 08/21/2008
• Est. Priority Date: 05/13/2005
• Status: Active Grant

• Current Assignee: Fractus SA
• Original Assignee: Fractus SA
• Inventors: Soler Castany, Jordi, Puente Baliarda, Carles, Mumbru Forn, Josep
• Granted Patent: US 8,531,337 B2
• Time in Patent Office: Days
• US Class Current: 343/770
• CPC Class Codes: H01Q 1/242 specially adapted for hand-held use
• 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 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 21/28 Combinations of substantially independent non-interacting antenna units or systems multiple beam H01Q25/00
• CPC Class Codes: H01Q 9/30 with feed to end of elongated active element, e.g. unipole H01Q9/44 takes precedence

Abstract

The present invention refers to an antenna diversity system comprising at least a first antenna and a second antenna wherein the first antenna substantially behaves as an electric current source or as a magnetic current source, and the second antenna substantially behaves as an electric current source or as a magnetic current source and a corresponding wireless device. Further the invention relates to an SMT-type slot-antenna component comprising at least one conductive surface or sheet of metal in which the pattern of a slot is created, at least one contact terminal accessible from the exterior of said component to electrically connect the conductive surface included in the slot-antenna component with the ground plane of a circuit board such as a printed circuit board and a corresponding wireless device.

Claims

1. An antenna diversity system comprising at least a first antenna and a second antenna wherein the first antenna substantially behaves as an electric current source or as a magnetic current source, and the second antenna substantially behaves as an electric current source or as a magnetic current source.

2. An antenna diversity system according to claim 1, wherein the first antenna (2) is an electric current source and the second antenna (3) is a magnetic current source.

3. An antenna diversity system according to claim 2, wherein the second antenna (3) is a slot antenna.

4. An antenna diversity system according to claim 2, wherein the first antenna (2) is selected from a group comprising:

a monopole antenna, a patch antenna, an IFA (42), a PIFA and a multiband antenna (52).

5. An antenna diversity system according to claim 4, wherein the first antenna is printed as a conductive layer on a circuit board (4) or is etched from a conductive layer of a circuit board (4).

6. An antenna diversity system according to claim 3, wherein said slot antenna is inscribed in a rectangular area (7) the width (6) of which is smaller than 1/50 of a free-space operating wavelength, and/or the length (5) of which is smaller than ¼

of a free-space operating wavelength.

7. An antenna diversity system according to claim 3, wherein said slot antenna is inscribed in a rectangular area (7) the width (6) of which divided by a free-space operating wavelength is smaller than, or equal to, at least one of the fractions of the group comprising:

1/10, 1/30, 1/50, 1/60, 1/70, or 1/80.

8. An antenna diversity system according to claim 3, wherein said slot antenna is inscribed in a rectangular area (7) the length (5) of which divided by a free-space operating wavelength of the said slot antenna is smaller than, or equal to, at least one of the fractions of the group comprising:

½

, ⅓

, or ¼

.

9. An antenna diversity system according to claim 3, wherein said slot antenna is inscribed in a rectangular area (7) the length (5) of which divided by a free-space operating wavelength of the said slot antenna is smaller than, or equal to, at least one of the fractions of the group comprising:

⅕

, ⅙ and

⅛

.

10. An antenna diversity system according to claim 3, wherein the said slot antenna (3) is printed as a conductive layer on a circuit board (4) or etched from a conductive layer of a circuit board (4).

11. An antenna diversity system according to claim 10, wherein said conductive layer is capable of operating as a ground plane of the antenna system of the antenna diversity system (1).

12. An antenna diversity system according to claim 3, wherein the slot comprises at least one, two, three, four, five or more substantially straight and/or curved segment/segments, of which one, two, three, four, five or more preferably have the same or different length.

13. An antenna diversity system according to claim 12, wherein the separation between the edges of at least one, two, three, four, or more segments is the same and/or constant.

14. An antenna diversity system according to claim 12, wherein the separation between the edges of at least one, two, three, four, or more segments is within a minimum and a maximum fraction of a free-space operating wavelength of said slot antenna, wherein said minimum and maximum fraction are selected from the set comprising:

0.08%, 0.16%, 0.32%, 0.5%, 1%, 2%, 4%, 6%, and 8%.

15. An antenna diversity system according to claim 12, wherein the longest segment, preferably the longest straight segment, of the slot is substantially parallel to the longest edge, extension or symmetry axis of a circuit board (4).

16. An antenna diversity system according to claim 3, wherein the slot has an open end which is provided at one edge of a circuit board (4).

17. An antenna diversity system according to claim 3, wherein the said slot antenna is embedded in a component that can be or is mounted on a circuit board (4) such as for example an SMT component.

18. An antenna diversity system according to claim 17, wherein the slot (3) comprises at least one, two three, four, five or more substantially straight and/or curved segments, of which one, two, three, four five or more preferably have the same or different length.

19. An antenna diversity system according to claim 18, wherein the separation between the edges of at least one, two, three, four, or more segments is the same and/or constant.

20. An antenna diversity system according to claim 18, wherein the separation between the edges of at least one, two, three, four, or more segments is within a minimum and a maximum fraction of a free-space operating wavelength of said slot antenna, wherein said minimum and maximum fraction are selected from the set comprising:

0.08%, 0.16%, 0.32%, 0.5%, 1%, 2%, 4%, 6%, and 8%.

21. An antenna diversity system according to claim 18, wherein the longest segment, preferably the longest straight segment, of the slot (3) is substantially parallel to the longest edge, extension or symmetry axis of the component.

22. An antenna diversity system according to claim 17, wherein said slot (3) has an open end which is provided at one edge of the component or a conductive layer of said component.

23. An antenna diversity system according to claim 3, wherein at least two, three, four or more portions of said slot (3) are parallel to each other.

24. An antenna diversity system according to claim 3, wherein the area of a smallest possible rectangular area which completely encloses the slot of the slot antenna (3) or the perpendicular projection of the slot onto the plane of the circuit board (4) divided by the area of the circuit board is equal to or less than a fraction of the group comprising:

⅕

, 1/7, 1/10, 1/15, 1/20, 1/15, 1/30, 1/40, 1/50, 1/60, 1/70, 1/80, 1/90, 1/100, 1/120, 1/140, 1/160, 1/180, 1/200, 1/250, 1/300, 1/400, 1/500, 1/1000.

25. An antenna diversity system according to claim 1, wherein the electric currents excited on at least a portion of the circuit board (4) by the radiating mode of the said first antenna (2) are substantially parallel to the magnetic currents excited on at least a portion of the extension of the said second antenna (3).

26. An antenna diversity system according to claim 1, wherein the first antenna (102) and the second antenna (103) is a magnetic current source.

27. An antenna diversity system according to claim 26, wherein the first and/or the second antenna are slot antennas (102, 103).

28. An antenna diversity system according to claim 27, wherein the longest portion of the first slot antenna (102) and the second slot antenna (103) or extension or side of a smallest enclosing rectangle of the first slot antenna and the (102) second slot antenna (103) are substantially perpendicular.

29. An antenna diversity system according to claim 27, wherein the first slot antenna (102) has an open end on a first edge of a circuit board (4) and the second slot antenna (103) has an open end on a second edge of said circuit board (4), said first and second edges being substantially perpendicular.

30. An antenna diversity system according to claim 26, wherein the magnetic currents excited on at least a portion of the extension of the first antenna (102) are substantially orthogonal to the magnetic currents excited on at least a portion of the extension of the second antenna (103).

31. An antenna diversity system according to claim 1, wherein the first antenna and the second antenna behave as electric current sources.

32. An antenna diversity system according to claim 31, wherein the electric currents excited on a printed circuit board, by the radiating mode of the first antenna, are substantially orthogonal to the electric currents excited on the said printed circuit board by the radiating mode of the second antenna, in at least a portion of the printed circuit board.

33. An antenna diversity system according to claim 31, wherein the first and/or the second antenna is selected from the group comprising:

a monopole antenna, patch antenna, IFA, a PIFA and a multiband antenna.

34. An antenna diversity system according to claim 1, wherein said first antenna (2) of the said at least two antennas is radiating with a first polarization, and said second antenna (3) of the said at least two antennas is radiating with a second polarization, wherein the said first polarization and second polarization are substantially orthogonal.

35. An antenna diversity system according to claim 1, wherein the first and/or the second antenna (2, 3) is/are multiband antenna/antennas having one, two three or more frequency bands in common.

36. An antenna diversity system according to claim 1, wherein the first and/or the second antenna (2, 3) are located on a corner or not separated more than 1%, 5%, 10% or 20% of the longest circuit board extension (76) or respective antenna extension from a corner of a circuit board carrying the antennas.

37. An antenna diversity system according to claim 1, wherein the first and/or the second antenna (2, 3) are located on an edge (73) of a circuit board (4) carrying the antennas or not further separated from the edge than 1%, 5%, 10% or 20% than the longest extension (76) of the circuit board (4) or of the longest extension of the respective antenna.

38. Antenna diversity system according to claim 1, wherein the first and/or second antenna (2, 3) are covering the middle (74) of an edge (73) or is/are not more separated from the middle (74) than 1%, 5%, 10% or 20% than the longest extension of the circuit board (4) or the extension (e1, e2) of the antenna (72) in the respective direction.

39. Antenna diversity system according to claim 1, wherein the separation (79) between first and second antenna (77, 78) is not more than a percentage of the longest extension (76) of a circuit board (4) carrying the antennas (2, 3), the percentage being chosen from the group comprising:

1%, 2%, 3%, 5%, 7%, 10%, 12%, 15%, 20%, 30%, 40% and 50%.

40. Antenna diversity system according to claim 1, wherein the separation (79) between the first antenna (77) and the second antenna (78) is more than a percentage of the longest extension (76) of a circuit board carrying the antennas, the percentage being chosen from the group comprising:

50%, 60%, 70%, 75%, 80%, 85%, 90% and 95%.

41. An antenna diversity system according to claim 1, wherein at least the first and/or the second antenna (2, 3) is integrated each in a respective semiconductor package.

42. An antenna diversity system according to claim 41, wherein at least one or two of said semiconductor packages include an electronic circuit.

43. An antenna diversity system according to claim 42, wherein said electronic circuit comprises an electronic die.

44. An antenna diversity system according to claim 1, wherein at least one of the said at least two antennas (2, 3) is operating not only in the same frequency band as the other antennas, but is also operating, at least, at some other frequency band used for mobile telephone systems.

45. An antenna diversity system according to claim 1, wherein at least a portion which defines the conducting trace, conducting wire or contour of at least one of the antennas (2, 3), or at least a portion of a slot (113) or the entire slot (113), is shaped as a space-filing curve, or a box-counting, or a grid dimension curve or a fractal curve.

46. An antenna diversity system according to claim 1, wherein at least a portion of at least one of the antennas (2, 3) is a polygonal or multilevel structure or coupled to a polygonal or multilevel structure.

47. An antenna diversity system comprising at least a first antenna (3) and a second antenna (2), and a circuit board (4) such as a printed circuit board on which the said at least first antenna (3) and second antenna (2) are mounted, printed or etched;

wherein the first antenna (3) substantially behaves as a magnetic current source and the second antenna (2) substantially behaves as an electric current source;

wherein said first antenna (3) of the said at least two antennas is radiating with a first polarization, and said second antenna (2) of the said at least two antennas is radiating with a second polarization, wherein the said first polarization and second polarization are substantially orthogonal;

wherein the said first antenna (3) is a slot antenna, wherein the longest straight segment of the slot (3) is substantially parallel to the longest edge of the said circuit board (4), wherein one open end of the slot (3) is in contact with one edge of the said circuit board (4);

wherein the width of the rectangular area (7) in which the said slot antenna is inscribed, divided by a free-space operating wavelength of the said slot antenna is smaller than, or equal to, at least one of the following fractions;

1/10, 1/30, 1/50, 1/60, 1/70, or 1/80;

and wherein the length of the rectangular area (7) in which the said slot antenna (3) is inscribed, divided by a free-space operating wavelength of the said slot antenna is smaller than, or equal to, at least one of the following fractions;

½

, ⅓

, or ¼

.

48. The antenna diversity system of claim 47 disposed in a wireless communication device.

49. A wireless device according to claim 47, wherein the device is at least one or a combination of wireless devices of a group of wireless devices comprising:

a cellular phone, a mobile phone, a handheld phone, a smart phone, a satellite phone, a multimedia terminal, personal digital assistant (PDA), a portable music player, a radio, a digital camera, a USB dongle, a wireless headset, an ear phone, a hands-free kit, an electronic game, a remote control, an electric switch, a light switch, an alarm, a car kit, a computer card, a PCMCIA card, a sensor, a headset, a dongle, a computer interface a computer mouse, a keyboard, a personal computer, a MP3 player, a portable DVD/CD player, a smoke detector, a switch, a motion sensor, a pressure sensor, a temperature sensor, a medical sensor, a meter, a short/medium range wireless connectivity application, a Mini-PCI, a Notebook, PC with WiFi module integrated, a compact flash wireless card, a UART dongle, a pocket PC with integrated Wi-Fi, an access point for a hot spot, a wireless wrist watch, a wireless wrist sensor, a bracelet FM radio, an MP3 player, a radio frequency identification tag, key remote entry system, an air pressure sensor e.g. in a tire, a radio controlled toy, a laptop and a cardbus 32 card.

50. A wireless device according to claim 49, wherein the device is configured for operation in one, two, three or more of the wireless communication systems preferably selected from the group comprising:

Bluetooth, 2.4 GHz Bluetooth, 2.4 GHz WiMAX, ZigBee, ZigBee at 860 MHz, ZigBee at 915 MHz, GPS, GPS at 1.575 GHz, GPS at 1.227 GHz, Galileo, GSM 450, GSM 850, GSM 900, GSM 1800, American GSM, DCS-1800, UMTS, CDMA, DMB, WLAN, WLAN at 2.4 GHz-6 GHz, PCS1900, KPCS, WCDMA, SDARs, XDARS, DAB, WiFi, UWB, 2.4-2.483 GHz band, 2.471-2.497 GHz band, IEEE802.11ba, IEEE802.11b, IEEE802.11g and FM.

51. A wireless device according to claim 49, wherein the device is configured for operation in at least the DVB-H wireless communication system.

52. An SMT-type slot-antenna component (110) comprising:

at least one conductive surface (111) or sheet of metal in which the pattern of a slot (113) is created;

at least one contact terminal (105) accessible from the exterior of said component to electrically connect the conductive surface included in the slot-antenna component with the ground plane of a circuit board such as a printed circuit board (121);

53. The SMT-type slot-antenna component according to claim 52, further comprising a dielectric substrate that backs the conductive surface (111) or sheet of metal or in which said conducting surface or sheet of metal is embedded.

54. The SMT-type slot-antenna component according to claim 52, which does or does not form part of an antenna diversity system.

55. The SMT-type slot-antenna component according to claim 52, further comprising at least one contact terminal (114) to couple a radio-frequency feeding signal from the outside of the SMT-type slot-antenna component with the slot defined in said conductive surface (111).

56. The SMT-type slot-antenna component according to claim 52, further comprising at least one, two, three, four or more further grounding terminals (115a-115e).

57. The SMT-type slot-antenna component according to claim 52, further comprising at least one, two, three, four or more further feeding terminals (104).

58. The SMT-type slot-antenna component according to claim 52, wherein at least one, two, three or more grounding terminals (1144a, 144b) are arranged such that they are also suitable for feeding a radio-frequency feeding signal from the outside of the SMT-type slot-antenna component with the slot defined in said conductive surface.

59. The SMT-type slot-antenna component according to claim 52, wherein at least one, two, three, four or more grounding terminals (145)/feeding terminals (114, 164) are arranged such that they can only be used as grounding/feeding terminals.

60. The SMT-type slot-antenna component according to claim 52, further comprising one, two, three or more electronic elements or circuits, which preferably are arranged such that they are not in the projection of the slot contained in the SMT-type slot-antenna component.

61. The SMT-type slot-antenna component according to claim 52, comprising more than one, two or three conductive surfaces (191, 192), in which a slot or one, two, three or more portion (193)/portions (194, 195) of a slot are provided.

62. The SMT-type slot-antenna component according to claim 52, wherein two conductive surfaces are provided on the two opposite sides of the dielectric substrate.

63. The SMT-type slot-antenna component according to claim 61, wherein at least two conductive surfaces are electrically connected for example with via holes (196, 197) or are not electrically connected.

64. The SMT-type slot-antenna component according to claim 52, wherein the conductive surface is covered by a dielectric layer such as for example ink or a layer of protective epoxy coating, in which preferably one, two, three or more windows are left, in order to create one, two, three or more contact terminals.

65. The SMT-type slot-antenna component according to claim 52, wherein the slot is open at none, one or two ends and is closed at the remaining ends.

66. The SMT-type slot-antenna component according to claim 52, wherein grounding terminals (115a-115d) are located close to at least two opposite edges of the slot-antenna component, preferably those two edges that are farthest apart from each other.

67. The SMT-type slot-antenna component according to claim 66, wherein grounding terminals (115a-115d) are located close to at least two corners of said at least two opposite edges, preferably at the four corners of said two opposite edges.

68. The SMT-type slot-antenna component according to claim 52, wherein at least one, two, three or four grounding terminals (145) extend along an edge of the component or the conductive surface or at least along 40%, 50%, 60%, 70%, 80%, 90% or 95% of said edge.

69. The SMT-type slot-antenna component according to claim 52, wherein grounding terminals (115a, 115e, 165a, 165b) are placed at two sides of a feeding terminal (114, 164) and preferably substantially close to said feeding terminal (114, 164).

70. The SMT-type slot-antenna component according to claim 52, wherein feeding terminals (144a, 144b) are provided on two sides of the slot (143).

71. The SMT-type slot-antenna component according to claim 52, wherein a conductive strip (118, 168) is connecting the edge of the slot (113, 163) farther away from the feeding terminal (114, 164).

72. The SMT-type slot-antenna component according to claim 71, wherein said conductive strip (118, 168) and the conductive surface (111, 161) are coplanar.

73. The SMT-type slot-antenna component according to claim 52, wherein a clearance region (120, 170) is provided at least on two sides of a feeding terminal (114, 164).

74. The SMT-type slot-antenna component according to claim 71, wherein the width (d1, d2) of the clearance region of the feeding terminal (114, 164) and/or the width of the conductive strip (118, 168) is smaller than a maximum value of the group comprising:

1/2400, 1/1200, 1/800, 1/600 1/480, 1/400, 1/300, 1/240, 1/200, 1/150 and 1/120 of a free space operating wavelength of the slot antenna.

75. The SMT-type slot-antenna component according to claim 71, wherein a clearance region (120, 170) is provided at both sides of the conductive strip (118, 168).

76. The SMT-type slot-antenna component according to claim 71, wherein the feeding terminal (114, 164) is coupled to the conductive strip (118, 168) by conductive coupling such as by a direct electric connection, a via hole, by capacitive coupling or inductive coupling.

77. A wireless device such as a handheld or portable device comprising a circuit board (121) such as a printed circuit board and an SMT-type slot-antenna component of claim 52 wherein the circuit board (121) comprises a ground plane (131).

78. The wireless device according to claim 77, wherein the ground plane (131) of the circuit board has a clearance (132) at least in a part of the orthogonal projection (150) of the SMT-type slot-antenna component onto the circuit board on which the component is mounted.

79. The wireless device according to claim 77, wherein the ground plane (131) of the circuit board is provided in a portion of the orthogonal projection of the SMT-type slot antenna component onto the circuit board on which the component is mounted, but not in the orthogonal projection of the slot of the conductive surface of the SMT-type slot-antenna component on the circuit board.

80. The wireless device according to claim 77, wherein the ground plane (131) of the circuit board (121) is provided in a portion of the orthogonal projection of the SMT-type slot antenna component onto the circuit board on which the component is mounted, and also in a fraction of the projection of the slot wherein the fraction is less or equal to a value of the group comprising 50%, 40%, 30%, 25%, 20%, 15%, 10% and 5%.

81. The wireless device according to claim 77, wherein one, two, three, four, five or more protrusions (135) of the ground plane (131) of the circuit board extend into the clearance (132).

82. The wireless device according to claim 77, wherein the size of the clearance (132) of the ground plane of the circuit board is smaller than the size of the SMT-type slot-antenna component or smaller than 90%, 80%, 70%, 60%, 50%, 40%, 30% or 20% of the size of the SMT-type slot-antenna component and/or larger than 10%, 20%, 30%, 40%, 50%, 60%, 70% 80%, 90% of the size of the SMT-type slot-antenna component.

83. The wireless device according to claim 77, wherein one, two, three or more portions (153) of the antenna slot is provided in the ground plane (121) of the circuit board, wherein one, two, three or more slots (153) of the ground plane (121) and the slot (143) of the SMT-type slot-antenna component (150) are preferably connected.

84. The wireless device according to claim 77, wherein an edge preferably a long edge of the SMT-type slot-antenna component (150) is oriented along a long or short edge of the circuit board.

85. The wireless device according to claim 77, wherein the SMT-type slot-antenna component (150) is provided not farther away from an edge of the circuit board (151) by more than the extension of the component (150) in the direction perpendicular to the edge of the circuit board or not farther away than 80%, 60%, 40%, or 20% of said extension.

86. The wireless device according to claim 77, wherein the SMT-type slot-antenna component is provided at the middle (74) of an edge (73) of the ground plane of the circuit board or not farther away from a middle than the extension of the component along the edge or not farther away than 80%, 60%, 40%, or 20% of said extension.

87. The wireless device according to claim 77, wherein the slot is contacted for balanced or unbalanced feeding.

88. The wireless device according to claim 77, wherein a coplanar transmission line (181), a coaxial transmission line (184) or a microstrip transmission line (186) is provided for exciting the slot.

89. The wireless device according to claim 77, wherein two, three, four or more SMT-type slot-antenna components of any of claims 52 to 76 are provided.

90. The wireless device according to claim 89, wherein at least two SMT-type slot-antenna components (211, 212) are arranged substantially orthogonal to each other.

91. The wireless device according to claim 77, wherein at least two slot antennas (211, 212) are provided, none, one or two of them being provided with an SMT-type slot-antenna component of any of claims 52 to 76, wherein the two slot antennas can radiate with orthogonal polarizations.

92. The wireless device according to claim 77, wherein the circuit board (121) comprises a pad (134) which is connected to the feeding terminal (114) of the SMT-type slot-antenna component (110), wherein this pad (134) is or is not connected to the ground plane of the circuit board.

93. The wireless device according to claim 77, wherein the SMT-type slot-antenna component is square with a length L or rectangular with a length L which is the longer dimension of the rectangle, wherein L divided by a free space operating wavelength of the slot antenna is smaller than or approximately equal to a fraction of the group comprising:

⅕

, ⅛

, 1/10, 1/12, 1/13, 1/14, 1/15, 1/16, 1/18, and 1/20.

94. The wireless device according to claim 77, wherein the SMT-type slot-antenna component is rectangular with a width (W) which is the shorter dimension of the rectangle, wherein the width (W) divided by a free-space operating wavelength of the slot antenna is smaller than or approximately equal to a fraction of the group comprising:

1/10, 1/15, 1/18, 1/20, 1/21, 1/22, 1/23, 1/24, 1/25, and 1/30.

95. The wireless device according to claim 77, wherein the SMT-type slot-antenna component has a height (H), wherein the height (H) divided by a free-space operating wavelength of the slot antenna is smaller than or approximately equal to a fraction of the group comprising:

1/40, 1/60, and 1/120.

96. The wireless device according to claim 77, wherein the SMT-type slot antenna component (150) together with a connected slot portion (153) in the ground plane (151) of the circuit board (121) fits into a rectangular area of width (W′

) and length (L′

), wherein the sum of said length (L′

) and width (W′

) divided by a free space operating wavelength is less than or approximately equal to a percentage of the group comprising 25%, 22.5%, 20%, 17.5%, 15%, 12.5%, and 10%.

97. The wireless device according to claim 77, wherein the unfolded length of the slot-portion (153) in the ground plane (151) of the circuit board (121 divided by the unfolded length of the combination of the slot (143) and said slot portion (153) is less than a percentage of the group comprising 50%, 40%, 30%, 25%, 20%, 18%, 16%, 14%, 12%, 10% and 5%.

98. The wireless device according to claim 77, wherein the separation between two edges of a slot (113, 143) and/or a slot portion (153) in the ground plane (131, 151) of the circuit board (121) divided by a free space operating wavelength is less than a percentage of the group comprising 8%, 4%, 2%, 1%, and 0.5%, and/or more than a percentage of the group comprising 0.08%, 0.12%, 0.16%, 0.20%, and 0.24%.

99. The wireless device according to claim 77, wherein the slot (143) of the SMT-type slot-antenna component (150) in combination with a slot portion (153) in the ground plane (151) of the circuit board (121) is open at none, one or two ends (146) and closed at the other ends.

100. The wireless device according to claim 77, wherein for exciting the slot region (158) a coplanar transmission line (181), a coaxial transmission line (184) or a microstrip transmission line (186) is provided.

101. The wireless device according to claim 77, wherein the slot antenna is closed at one end and the slot or slot section can be excited by applying a voltage difference between opposite conductive edges of the slot or slot section at a certain point along the geometry of the slot, wherein said point is closer to the closed end along the geometry of the slot than to the other end and/or the distance between said point and said closed end divided by a free space operating wavelength is less than or equal to a value of the group comprising:

0.002, 0.004, 0.008, 0.012, 0.016, 0.025, 0.033, 0.04, 0.08, 0.1 and 0.15.

102. The wireless device according to claim 77, wherein the SMT-type slot-antenna component (211) of any of claims 52 to 76 has a longer dimension which is substantially perpendicular to a longer dimension of a second SMT-type slot-antenna component (212) of any of claims 52 to 76.

103. The wireless device according to claim 77, wherein the SMT-type slot-antenna component (211) of any of claims 52 to 76 and a second SMT-type slot-antenna component (212) of any of claims 52 to 76 form or form part of an antenna diversity system.

104. The wireless device according to claim 77, wherein at least a portion of a curve defining the slot or a slot section is a space filling curve, a box counting curve, a grid-dimension curve or a fractal based curve.

105. The wireless device according to claim 77, wherein a curve defining the slot or the slot section branches out in two or more curves, which preferably are space filling, box-counting, grid-dimension or fractal based curves.

106. The wireless device according to claim 77, wherein the slot of the slot antenna is formed like a polygonal or multilevel surface or coupled through direct contact or electromagnetic coupling to a conducting polygonal or multilevel surface or polygonal or multilevel shaped slot.

107. The wireless device according to claim 77, wherein the wireless device is at least one or a combination of wireless devices of a group of wireless devices comprising:

a cellular phone, a mobile phone, a handheld phone, a smart phone, a satellite phone, a multimedia terminal, personal digital assistant (PDA), a portable music player, a radio, a digital camera, a USB dongle, a wireless headset, an ear phone, a hands-free kit, an electronic game, a remote control, an electric switch, a light switch, an alarm, a car kit, a computer card, a PCMCIA card, a sensor, a headset, a dongle, a computer interface a computer mouse, a keyboard, a personal computer, a MP3 player, a portable DVD/CD player, a smoke detector, a switch, a motion sensor, a pressure sensor, a temperature sensor, a medical sensor, a meter, a short/medium range wireless connectivity application, a Mini-PCI, a Notebook, PC with WiFi module integrated, a compact flash wireless card, a UART dongle, a pocket PC with integrated Wi-Fi, an access point for a hot spot, a wireless wrist watch, a wireless wrist sensor, a bracelet FM radio, an MP3 player, a radio frequency identification tag, key remote entry system, an air pressure sensor e.g. in a tire, a radio controlled toy, a laptop and a cardbus 32 card.

108. The wireless device according to claim 77, wherein the wireless device is configured for operation in one, two, three or more of the wireless communication systems preferably selected from the group comprising:

Bluetooth, 2.4 GHz Bluetooth, 2.4 GHz WiMAX, ZigBee, ZigBee at 860 MHz, ZigBee at 915 MHz, GPS, GPS at 1.575 GHz, GPS at 1.227 GHz, Galileo, GSM 450, GSM 850, GSM 900, GSM 1800, American GSM, DCS-1800, UMTS, CDMA, DMB, DVB-H, WLAN, WLAN at 2.4 GHz-6 GHz, PCS1900, KPCS, WCDMA, SDARS, XDARS, DAB, WiFi, UWB, 2.4-2.483 GHz band, 2.471-2.497 GHz band, IEEE802.11ba, IEEE802.11b, IEEE802.11g and FM.

109. A wireless device such as a handheld or portable device comprising a circuit board (121) such as a printed circuit board and a slot-antenna component (110), wherein said circuit board (121) comprises a ground plane, and wherein said slot-antenna component comprises:

at least one conductive surface (111), different from the ground plane of the circuit board (121), on which a pattern of a slot (113) is created;

a dielectric substrate (112) that backs said at least one conductive surface (111), or in which said at least one conducting surface (111) is embedded;

at least one contact terminal (115a, 115b) named grounding terminal accessible from the exterior of said slot-antenna component (110) to electrically connect said at least one conductive surface (111) included in the slot-antenna component with the ground plane of the circuit board (121);

and at least one contact terminal (114) named feeding terminal to couple a radio-frequency feeding signal from the outside of the slot-antenna component (110) with the slot (113) defined in said at least one conductive surface (111);

wherein said slot-antenna component (110) has a rectangular shape with a length (L) smaller than 1/10 of a free-space operating wavelength of the slot antenna, a width (W) smaller than 1/15 of a free-space operating wavelength of the slot antenna and a height (H) smaller than 1/60 of a free-space operating wavelength of the slot antenna;

wherein the unfolded length of the slot antenna comprising the slot (113) created in said at least one conductive surface (111) of the slot-antenna component is approximately a quarter of an operating wavelength of the slot antenna;

wherein at least a portion of the slot (113) created in said at least one conductive surface of the slot-antenna component is shaped as a space-filling curve, or a box-counting curve, or a grid dimension curve;

wherein the slot-antenna component (110) comprises a second grounding terminal (115c, 115d);

wherein the first and second grounding terminals (115a, 155b, 115c, 155d) are close to two opposite edges of said slot-antenna component (110);

wherein the slot-antenna component (110) comprises feeding means including a conductive strip (118) connected to the at least one feeding terminal (114), and having a width smaller than 1/300 of a free-space operating wavelength of the slot antenna;

wherein said conductive strip (118) is connected to an edge of the slot (113) created in the at least one conductive surface (111) of the slot-antenna component (110) at a distance from a closed end (117) of said slot (113) smaller than 8% of a free-space operating wavelength of the slot antenna;

and wherein the wireless device is operating at one, two, three or more communication and connectivity services selected from the group comprising GSM850, GSM900, GSM1800, American GSM, PCS1900, GSM450, UMTS, WCDMA, CDMA, Bluetooth™

, IEEE802.11a, IEEE802.11b, IEEE802.11g, WLAN, WiFi, UWB, ZigBee, GPS, Galileo, SDARs, XDARS, WiMAX, DAB, FM, DMB, and DVB-H.