Anti-reflective interference antennas with radially-oriented elements

• US 20070109193A1
• 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 7,446,714 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 interference immunity properties, comprising:

a rigid planar structure, said structure defining a plane;

a set of directional antenna elements incorporated in said plane, said elements arranged substantially equadistantly from a central point in said plane, said elements further arranged in a radially symmetrical configuration such that the distance between adjacent antenna elements are substantially equal, each of said directional antenna elements having a shape defining a direction of maximal gain;

transmission feed lines electrically connected to said antenna elements;

a combiner positioned substantially at said central point and further electrically connected to said antenna elements through said transmission feed lines, said combiner further providing a point of electrical connection for radio electronics;

whereby each of said directional antenna elements is oriented at the same angle with respect to said central point.

2. 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 regardless of the orientation of the array in said plane.

3. An antenna array according to claim 1, wherein said set of antenna elements consists of three elements arranged at the comers of an equalateral triangle.

4. An antenna array according to claim 1, wherein the feed impedance is kept substantially equal in said transmission lines between said combiner and said first, second and third elements

5. An antenna array according to claim 1, wherein in each of said transmission lines an equal propagation delay is maintained.

6. An antenna array according to claim 1, further comprising a ground plane layer.

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

a layer, said layer defining a plane;

a set of directional antenna elements incorporated in said plane, said elements arranged substantially equadistantly from a central point in said plane, said elements further arranged in a radially symmetrical configuration such that the distance between adjacent antenna elements are substantially equal, each of said directional antenna elements having a microstrip shape defining a direction of maximal gain;

transmission feed lines electrically connected to said antenna elements;

a combiner positioned substantially at said central point and further electrically connected to said antenna elements through said transmission feed lines, said combiner further providing a point of electrical connection for radio electronics;

whereby each of said directional antenna elements is oriented at the same angle with respect to said central point.

8. An antenna array according to claim 7, wherein the array presents at least two elements at a phase difference of other than one-half wavelength at the design frequency regardless of the orientation of the array in said plane.

9. An antenna array according to claim 7, wherein said set of antenna elements consists of three elements arranged at the comers of an equalateral triangle.

10. An antenna array according to claim 7, 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 7, wherein in each of said transmission lines an equal propagation delay is maintained.

12. An antenna array according to claim 7, further comprising a ground plane layer.

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

a printed circuit board including at least one layer;

a set of directional antenna elements incorporated in said layer, said elements arranged substantially equadistantly from a central point in said layer, said elements further arranged in a radially symmetrical configuration such that the distance between adjacent antenna elements are substantially equal, each of said directional antenna elements having a microstrip shape defining a direction of maximal gain;

transmission feed lines electrically connected to said antenna elements;

a combiner positioned substantially at said central point and further electrically connected to said antenna elements through said transmission feed lines, said combiner further providing a point of electrical connection for radio electronics;

whereby each of said directional antenna elements is oriented at the same angle with respect to said central point.

14. An antenna array according to claim 13, wherein the array presents at least two elements at a phase difference of other than one-half wavelength at the design frequency regardless of the orientation of the array in said plane.

15. An antenna array according to claim 13, wherein said set of antenna elements consists of three elements arranged at the comers of an equalateral triangle.

16. An antenna array according to claim 13, wherein the feed impedance is kept substantially equal in said transmission lines between said combiner and said first, second and third elements

17. An antenna array according to claim 13, wherein in each of said transmission lines an equal propogation delay is maintained.

18. An antenna array according to claim 13, further comprising a ground plane layer.