Card-based diversity antenna structure for wireless communications

• US 20020101377A1
• Filed: 12/13/2000
• Published: 08/01/2002
• Est. Priority Date: 12/13/2000
• Status: Active Grant

• Current Assignee: CommWorks Solutions, LLC (IP Investments Group LLC)
• Original Assignee: Magis Networks, Inc. (ON Semiconductor Corporation)
• Inventors: Crawford, James A.
• Granted Patent: US 6,456,245 B1
• Time in Patent Office: Days
• US Class Current: 343/702
• CPC Class Codes: H01Q 1/2275 associated to expansion card or bus, e.g. in PCMCIA, PC cards, Wireless USB
• 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 23/00 Antennas with active circuits or circuit elements integrated within them or attached to them
• 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 9/30 with feed to end of elongated active element, e.g. unipole H01Q9/44 takes precedence
• CPC Class Codes: H04B 7/04 using two or more spaced independent antennas
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity

Abstract

A card-based diversity antenna structure includes a card and at least two antenna elements. The card has active circuitry attached thereto and connectors located at a first end thereof configured for engagement with an interface slot. The at least two antenna elements are attached to the card at a second end thereof and are coupled to the active circuitry. At least two antenna elements are sufficiently spaced apart so as to achieve spatial diversity. The polarizations of two of the at least two antenna elements may be orthogonal to each other so as to achieve polarization diversity. The antenna structure delivers good receive and transmit diversity performance and is well suited to the form factor limits imposed by the dimensions of small cards, such as PCMCIA cards. The configuration is very convenient for application in the 5 to 6 GHz frequency band.

Claims

1. An antenna structure, comprising:

a card;

at least two antenna elements attached to the card at a first end thereof; and

active circuitry attached to the card and coupled to the at least two antenna elements;

wherein at least two of the at least two antenna elements are sufficiently spaced apart so as to achieve spatial diversity.

2. An antenna structure in accordance with claim 1, wherein the at least two antenna elements are spaced apart by a distance equal to or greater than 0.5λ

for a predetermined frequency of operation.

3. An antenna structure in accordance with claim 2, wherein the predetermined frequency of operation falls within 5 to 6 gigahertz (GHz).

4. An antenna structure in accordance with claim 1, wherein a first of the at least two antenna elements comprises a polarization that is orthogonal to a polarization of a second of the at least two antenna elements so as to achieve polarization diversity.

5. An antenna structure in accordance with claim 4, wherein the first antenna element comprises an active edge that is orthogonal to an active edge of the second antenna element.

6. An antenna structure in accordance with claim 4, wherein the first antenna element comprises a patch antenna and the second antenna element comprises a monopole antenna.

7. An antenna structure in accordance with claim 4, wherein the active circuitry comprises;

a first power amplifier coupled to the first antenna element; and

a second power amplifier coupled to the second antenna element.

8. An antenna structure in accordance with claim 1, wherein the card comprises connectors located at a second end thereof configured for engagement with an interface slot.

9. An antenna structure in accordance with claim 1, wherein at least one antenna element is located on a first surface of the card and at least one antenna element is located on a second surface of the card.

10. An antenna structure in accordance with claim 1, wherein one or more of the at least two antenna elements comprises a patch antenna.

11. An antenna structure in accordance with claim 1, wherein one or more of the at least two antenna elements comprises a monopole antenna.

12. An antenna structure in accordance with claim 1, wherein one or more of the at least two antenna elements comprises a vertically polarized antenna.

13. An antenna structure in accordance with claim 1, wherein one or more of the at least two antenna elements comprises a horizontally polarized antenna.

14. An antenna structure in accordance with claim 1, wherein the at least two antenna elements comprise four antenna elements.

15. An antenna structure in accordance with claim 14, wherein three of the antenna elements are located on a first surface of the card and one of the antenna elements is located on a second surface of the card.

16. An antenna structure in accordance with claim 14, wherein all four of the antenna elements comprise patch antennas.

17. An antenna structure in accordance with claim 14, wherein two of the antenna elements comprise patch antennas and two of the antenna elements comprise monopole antennas.

18. An antenna structure in accordance with claim 1, wherein the at least two antenna elements comprise six antenna elements.

19. An antenna structure in accordance with claim 18, wherein three of the antenna elements are located on a first surface of the card and three of the antenna elements is located on a second surface of the card.

20. An antenna structure in accordance with claim 18, wherein two of the antenna elements comprise patch antennas and four of the antenna elements comprise monopole antennas.

21. An antenna structure, comprising:

a card;

at least two antenna elements attached to the card at a first end thereof; and

active circuitry attached to the card and coupled to the at least two antenna elements;

wherein a first of the at least two antenna elements comprises a polarization that is orthogonal to a polarization of a second of the at least two antenna elements so as to achieve polarization diversity.

22. An antenna structure in accordance with claim 21, wherein the first antenna element comprises an active edge that is orthogonal to an active edge of the second antenna element.

23. An antenna structure in accordance with claim 21, wherein the first antenna element comprises a patch antenna and the second antenna element comprises a monopole antenna.

24. An antenna structure in accordance with claim 21, wherein the active circuitry comprises;

a first power amplifier coupled to the first antenna element; and

a second power amplifier coupled to the second antenna element.

25. An antenna structure in accordance with claim 21, wherein two of the at least two antenna elements are sufficiently spaced apart so as to achieve spatial diversity.

26. An antenna structure in accordance with claim 21, wherein two of the at least two antenna elements are spaced apart by a distance equal to or greater than 0.5λ

for a predetermined frequency of operation.

27. An antenna structure in accordance with claim 26, wherein the predetermined frequency of operation falls within 5 to 6 gigahertz (GHz).

28. An antenna structure in accordance with claim 21, wherein the card comprises connectors located at a second end thereof configured for engagement with an interface slot.

29. An antenna structure in accordance with claim 21, wherein at least one antenna element is located on a first surface of the card and at least one antenna element is located on a second surface of the card.

30. An antenna structure in accordance with claim 21, wherein one or more of the at least two antenna elements comprises a patch antenna.

31. An antenna structure in accordance with claim 21, wherein one or more of the at least two antenna elements comprises a monopole antenna.

32. An antenna structure in accordance with claim 21, wherein one or more of the at least two antenna elements comprises a vertically polarized antenna.

33. An antenna structure in accordance with claim 21, wherein one or more of the at least two antenna elements comprises a horizontally polarized antenna.

34. An antenna structure in accordance with claim 21, wherein the at least two antenna elements comprise four antenna elements.

35. An antenna structure in accordance with claim 34, wherein three of the antenna elements are located on a first surface of the card and one of the antenna elements is located on a second surface of the card.

36. An antenna structure in accordance with claim 34, wherein all four of the antenna elements comprise patch antennas.

37. An antenna structure in accordance with claim 34, wherein two of the antenna elements comprise patch antennas and two of the antenna elements comprise monopole antennas.

38. An antenna structure in accordance with claim 21, wherein the at least two antenna elements comprise six antenna elements.

39. An antenna structure in accordance with claim 38, wherein three of the antenna elements are located on a first surface of the card and three of the antenna elements are located on a second surface of the card.

40. An antenna structure in accordance with claim 38, wherein two of the antenna elements comprise patch antennas and four of the antenna elements comprise monopole antennas.

41. A method of receiving a signal in a multi-path environment, comprising the steps of:

placing a card in the multi-path environment, the card having active circuitry attached thereto;

receiving the signal with a first antenna element attached to the card at a first end thereof; and

receiving the signal with a second antenna element attached to the card at the first end thereof;

wherein the first and second antenna elements are coupled to the active circuitry.

42. A method in accordance with claim 41, wherein the first and second antenna elements are sufficiently spaced apart so as to achieve spatial diversity.

43. A method in accordance with claim 41, wherein the first and second antenna elements are spaced apart by a distance equal to or greater than 0.5λ

for a predetermined frequency of operation.

44. A method in accordance with claim 43, wherein the predetermined frequency of operation falls within 5 to 6 gigahertz (GHz).

45. A method in accordance with claim 41, wherein the first antenna element comprises a polarization that is orthogonal to a polarization of the second antenna element so as to achieve polarization diversity.

46. A method in accordance with claim 45, wherein the active circuitry comprises;

a first power amplifier coupled to the first antenna element; and

a second power amplifier coupled to the second antenna element.

47. A method in accordance with claim 41, wherein the card comprises connectors located at a second end thereof configured for engagement with an interface slot.

48. A method in accordance with claim 41, wherein the first antenna element is located on a first surface of the card and the second antenna element is located on a second surface of the card.

50. A method in accordance with claim 49, wherein the first and second antenna elements are sufficiently spaced apart so as to achieve spatial diversity.

51. A method in accordance with claim 49, wherein the first and second antenna elements are spaced apart by a distance equal to or greater than 0.5λ

for a predetermined frequency of operation.

52. A method in accordance with claim 51, wherein the predetermined frequency of operation falls within 5 to 6 gigahertz (GHz).

53. A method in accordance with claim 49, wherein the first antenna element comprises a polarization that is orthogonal to a polarization of the second antenna element so as to achieve polarization diversity.

54. A method in accordance with claim 53, wherein the active circuitry comprises;

a first power amplifier coupled to the first antenna element; and

a second power amplifier coupled to the second antenna element.

55. A method in accordance with claim 49, wherein the card comprises connectors located at a second end thereof configured for engagement with an interface slot.

56. A method in accordance with claim 49, wherein the first antenna element is located on a first surface of the card and the second antenna element is located on a second surface of the card.

49. A method of transmitting a signal in a multi-path environment, comprising the steps of:

placing a card in the multi-path environment, the card having active circuitry attached thereto;

transmitting the signal with a first antenna element attached to the card at a first end thereof; and

transmitting the signal with a second antenna element attached to the card at the first end thereof;

wherein the first and second antenna elements are coupled to the active circuitry.