Low profile high polarization purity dual-polarized antennas

• US 20010035844A1
• Filed: 06/25/2001
• Published: 11/01/2001
• Est. Priority Date: 01/18/2000
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Reece, John K., Aden, John L.
• Granted Patent: US 6,366,258 B2
• Time in Patent Office: Days
• US Class Current: 343/810
• CPC Class Codes: H01Q 21/062 using dipole aerials; H01Q21/067, H01Q21/068 take precedence
• 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 9/285 Planar dipole H01Q9/065 takes precedence; patch antenna H01Q9/0407

Abstract

An antenna system for use in cellular and other wireless communication includes a dual polarized compact antenna array. In one embodiment, the antenna system includes four T-shaped dipole antenna elements mounted on a ground plane, forming a side of a square shaped array. In another embodiment, the antenna system includes seven T-shaped dipole antenna elements mounted on a ground plane to form two side by side square arrays, wherein the square arrays share a common T-shaped dipole antenna element.

Claims

1. An antenna array, comprising:

a ground plane;

a first and a second T-shaped dipole antenna elements mounted along a first pair of mutually parallel axes of the ground plane;

a third and a fourth T-shaped dipole antenna elements mounted along a second pair of mutually parallel axes of the ground plane orthogonal to the first pair of mutually parallel axes;

a first power divider coupled to the first and second T-shaped dipole antenna elements; and

a second power divider coupled to the third and fourth T-shaped dipole antenna elements.

2. The antenna array of

claim 1

, wherein:

the first and second T-shaped dipole antenna elements are aligned to transmit and receive a first polarization; and

the third and fourth T-shaped dipole antenna elements are aligned to transmit and receive a second polarization orthogonal to the first polarization.

3. The antenna array of

claim 1

, wherein:

the ground plane includes a printed circuit copper cladding thereon; and

the first and second power dividers include microstrip lines formed from copper cladding deposited on the printed circuit.

4. The antenna array of

claim 1

, each of the first, second, third, and fourth T-shaped dipole antenna elements comprising:

a stem having a base, a top, and a pair of side edges;

a pair of laterally extending arms attached to the stem, each of the pair of laterally extending arms having a top edge and a bottom edge, the bottom edge of each arm including a first arcuate segment merging with a corresponding side edge of the stem and having a radius R1, and a second arcuate segment having a radius R2 greater than R1; and

a reactive feed strip extending along the stem.

5. The antenna array of

claim 4

, wherein the first arcuate segment forms a quarter circle.

6. The antenna array of

claim 5

, wherein:

R1 is approximately 5 millimeters; and

R2 is approximately 46 millimeters.

7. The antenna array of

claim 4

, wherein:

the top edge of each of the pair of laterally extending arms is aligned with the top of stem;

the stem has a longitudinally extending slot; and

the reactive feed strip extends along the stem by having a first portion extending from the base to a first point a first side of the slot, a second extending from a second point adjacent a second side of the slot towards the base, and a third portion extending between the first point and the second point.

8. The antenna array of

claim 7

, wherein:

wherein the stem has a length of approximately 50 millimeters; and

the slot has a width of approximately 3.8 millimeters and extends longitudinally from the top of the stem a length of approximately 24 millimeters.

9. The antenna array of

claim 8

, wherein the first, second, third, and fourth T-shaped dipole antenna elements form a square array, in which:

the first and second T-shaped dipole antenna elements are broadside to one another and spaced apart approximately 84 millimeters; and

the third and fourth T-shaped dipole antenna elements are broadside to one another and spaced apart approximately 84 millimeters, the T-shaped dipole antenna elements thereby forming a square array.

10. The antenna array of

claim 1

, further comprising a housing, the housing including:

a pair of coaxial connectors, a first one of the pair of coaxial connectors being coupled to the first power divider, and a second one of the pair of coaxial connectors being coupled to the second power divider;

a base providing a mounting for the ground plane and a mounting for the pair of coaxial connectors; and

a cover adapted to be coupled to the base.