Planar anti-reflective interference antennas with extra-planar element extensions

• US 20070109194A1
• Filed: 11/15/2005
• Published: 05/17/2007
• Est. Priority Date: 11/15/2005
• Status: Active Grant

• Current Assignee: Clearone Incorporated
• Original Assignee: ClearOne Communications Inc. (Clearone Incorporated)
• Inventors: Biddulph, Stuart
• Granted Patent: US 7,333,068 B2
• Time in Patent Office: Days
• US Class Current: 343/700.MS
• CPC Class Codes: H01Q 21/20 the units being spaced along or adjacent to a curvilinear path slotted waveguide arrays H01Q21/005; circularly or helically slotted waveguides H01Q21/0062
• CPC Class Codes: H01Q 21/205 providing an omnidirectional coverage turnstile aerials H01Q21/26
• CPC Class Codes: H01Q 9/0421 with a shorting wall or a shorting pin at one end of the element H01Q9/0414 takes precedence

Abstract

Disclosed herein are wireless products adapted to be positioned in a normal or resting position, that also include an antenna composed of a set of elements arranged in a plane in a radially symmetrical configuration providing a reduction in the susceptibility of reflected waves having the potential to cancel or weaken a main wave or signal, the plane positioned with respect to the normal position to direct a main communication line with a second wireless device into the plane and provide reception of a main and/or secondary signal at a plurality of phases. One exemplary product is a wireless conferencing device configured to rest on a tabletop, the antenna array oriented in a horizontal plane. Detailed information on various example embodiments of the inventions are provided in the Detailed Description below, and the inventions are defined by the appended claims.

Claims

1. A radio antenna array for use at a design frequency having reflective immunity properties, comprising:

a rigid planar structure, said structure defining a plane;

a first antenna element;

a second antenna element located a sufficient distance from said first element providing a substantial amount of phase difference for a signal travelling in a first direction passing through said first element and said second element;

a third antenna element located a sufficient distance from said first element providing a substantial amount of phase difference for a signal travelling in a second direction passing through said first element and said third element, whereby the second direction is different than the first direction;

transmission lines providing an electrical connection from said first, second and third antenna elements to a combiner;

wherein said first, second and third elements are located in said plane; and

wherein said first, second and third elements each incorporate an element extension that includes a portion extending substantially out of said plane.

2. An antenna array according to claim 1, wherein said first, second and third antenna elements are positioned at the corners of an equilateral triangle.

3. An antenna array according to claim 1, wherein the array presents at least two elements at a phase difference of other than one-half wavelength at the design frequency.

4. An antenna array according to claim 1, wherein said array is resonant at the design frequency.

5. An antenna array according to claim 1, wherein each of said extensions is formed as a shaft-like structure rising from the antenna element surface.

6. An antenna array according to claim 1, wherein each of said extensions is formed as a blade.

7. An antenna array according to claim 6, wherein each of said blade extensions is oriented in substantially the same direction as current travel in its connected antenna element.

8. An antenna array according to claim 1, further comprising a protective radome of sufficient thickness to encapsulate each of said extensions.

9. A radio antenna array for use at a design frequency having reflective immunity properties, comprising:

a layer, said layer defining a plane;

a first antenna element;

a second antenna element located a sufficient distance from said first element providing a substantial amount of phase difference for a signal travelling in a first direction passing through said first element and said second element;

a third antenna element located a sufficient distance from said first element providing a substantial amount of phase difference for a signal travelling in a second direction passing through said first element and said third element, whereby the second direction is different than the first direction;

transmission lines providing an electrical connection from said first, second and third antenna elements to a combiner;

a radome fashioned to cover said first, second and third antenna elements;

wherein said first, second and third elements are located in said plane; and

wherein said first, second and third elements each incorporate an element extension that includes a portion extending substantially out of said plane.

10. An antenna array according to claim 9, wherein the feed impedance is kept substantially equal in said transmission lines between said combiner and said first, second and third elements.

11. An antenna array according to claim 9, wherein in each of said transmission lines an equal propagation delay is maintained.

12. An antenna array according to claim 9, further comprising a ground plane layer.

13. An antenna array according to claim 9, wherein said first, second and third antenna elements are positioned at the comers of an equilateral triangle.

14. An antenna array according to claim 9, wherein the array presents at least two elements at a phase difference of other than one-half wavelength at the design frequency.

15. An antenna array according to claim 9, wherein said array is resonant at the design frequency.

16. An antenna array according to claim 9, wherein each of said extensions is formed as a shaft-like structure rising from the antenna element surface.

17. An antenna array according to claim 9, wherein each of said extensions is formed as a blade.

18. An antenna array according to claim 17, wherein each of said blade extensions is oriented in substantially the same direction as current travel in its connected antenna element.

19. A radio antenna array for use at a design frequency having reflective immunity properties, comprising:

a printed circuit board including at least one layer;

a first antenna element;

a second antenna element located a sufficient distance from said first element providing a substantial amount of phase difference for a signal travelling in a first direction passing through said first element and said second element;

a third antenna element located a sufficient distance from said first element providing a substantial amount of phase difference for a signal travelling in a second direction passing through said first element and said third element, whereby the second direction is different than the first direction;

an element extension attached to each of said first, second and third antenna elements;

a radome formed on said printed circuit board providing a protective covering for each of said first, second and third antenna elements;

transmission lines providing an electrical connection from said first, second and third antenna elements to a combiner; and

wherein said first, second and third elements are incorporated to said layer.

20. An antenna array according to claim 19, wherein the feed impedance is kept substantially equal in said transmission lines between said combiner and said first, second and third elements.

21. An antenna array according to claim 19, wherein in each of said transmission lines an equal propagation delay is maintained.

22. An antenna array according to claim 19, further comprising a ground plane layer.

23. An antenna array according to claim 19, wherein said first, second and third antenna elements are positioned at the corners of an equilateral triangle.

24. An antenna array according to claim 19, wherein the array presents at least two elements at a phase difference of other than one-half wavelength at the design frequency.

25. An antenna array according to claim 19, wherein said array is resonant at the design frequency.

26. An antenna array according to claim 19, wherein each of said extensions is formed as a shaft-like structure rising from the antenna element surface.

27. An antenna array according to claim 19, wherein each of said extensions is formed as a blade.

28. An antenna array according to claim 27, wherein each of said blade extensions is oriented in substantially the same direction as current travel in its connected antenna element.

29. An antenna array according to claim 19, wherein said radome has sufficient thickness to encapsulate each of said extensions.