Compact radiation structure for diversity antennas

• US 9,735,473 B2
• Filed: 09/17/2010
• Issued: 08/15/2017
• Est. Priority Date: 09/17/2010
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Warden, James Paul, Wang, Dong, Rao, Qinjiang
• Primary Examiner(s): Nguyen, Hoang
• Assistant Examiner(s): Tran, Hai
• Application Number:
  US13/823,723
• Publication Number:
  US 20130285867A1
• Time in Patent Office: 2,524 Days
• Field of Search: 343700 MS, 343702, 343795, 343770, 343843
• CPC Class Codes: H01Q 1/246 specially adapted for base stations
• 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 21/30 Combinations of separate antenna units operating in different wavebands and connected to a common feeder system
• CPC Class Codes: H01Q 5/371 Branching current paths
• CPC Class Codes: H01Q 5/378 Combination of fed elements with parasitic elements
• CPC Class Codes: H01Q 9/30 with feed to end of elongated active element, e.g. unipole H01Q9/44 takes precedence
• CPC Class Codes: H01Q 9/46 with rigid elements diverging from single point

Abstract

An antenna for diversity operation comprising a plurality of connected antenna units (100). The antenna units each having a first radiation element (102) with length of a quarter of a wavelength at a first operating frequency a second radiation element (104) with length of a quarter of a wavelength at a second operating frequency distinct from the first operating frequency, the second radiation element sharing with the first radiation element a segment of the first radiation element. A feed point for coupling a feed to one of said first or second radiation elements such that the elements resonate at the first and second operating frequencies respectively and at substantially orthogonal polarizations. Diversity antennas configured with two or more of the antenna units.

Claims

1. An antenna for diversity operation comprising:

a plurality of connected antennas each connected antenna having;

a first antenna with length of a quarter of a wavelength at a first operating frequency;

a second antenna with length of a quarter of a wavelength at a second operating frequency distinct from said first operating frequency, the second antenna sharing with said first antenna a segment of a conductor; and

a common feed point connected to said first or said second antennas such that said first antenna and said second antenna resonate at said first and second operating frequencies respectively and at least two of said connected antennas configured to have substantially orthogonal polarizations;

wherein the first antenna is a straight line having first and second ends and the second antenna is arranged with an open end partially encircling the first antenna; and

wherein the plurality of connected antennas are formed on a substrate, the first antennas of each of the plurality of connected antennas being connected together at a common connection point at the respective first ends of the first antenna, the plurality of connected antennas so connected being symmetric relative to at least one symmetry axis and wherein the substrate is spaced from a common ground plane.

2. The antenna of claim 1 wherein the second antenna is a meander line.

3. The antenna of claim 1 wherein the second antenna forms a perimeter of a rectangle around a portion of the first antenna.

4. The antenna of claim 1 wherein the second antenna forms a perimeter of a triangle around a portion of the first antenna.

5. The antenna of claim 1 including a parasitic element arranged in proximity to a first end of said first antenna.

6. The antenna of claim 5 said parasitic element geometric configuration being selected from one of a line, rectangle or circle.

7. The antenna of claim 1, including a plurality of feed points each located at said first end of each of the respective plurality of antennas.

8. The antenna of claim 7, including a shorting pin connected from said common connection point to said ground plane.

9. The antenna of claim 7, said plurality of antennas are formed on the substrate being arranged with their first antennas connected at a common connection point at respective first ends, the antennas so connected are symmetric relative to the at least one symmetry axis, said substrate being mounted orthogonally to a plane of a ground conductor;

and

said feed point being at a first or second antenna of one of the antennas closest proximity to the ground plane conductor.

10. The antenna of claim 1, wherein said feed point is located at said common connection point.

11. The antenna of claim 1 having two pairs of antennas formed on the substrate and arranged to be symmetric relative to the at least one symmetry axis with each of said pairs having their respective ends connected for forming said feed point.

12. The antenna of claim 1, wherein the first and second antennas are conductors.

13. The antenna of claim 1, wherein the first and second antennas are slots.

14. A wireless communication system comprising an antenna as claimed in claim 1.

15. The antenna of claim 1, wherein the first and second antennas are a combination of slots and conductors.

16. An antenna for diversity operation comprising:

a plurality of connected antennas each connected antenna having;

a first antenna with length of a quarter of a wavelength at a first operating frequency;

a second antenna with length of a quarter of a wavelength at a second operating frequency distinct from said first operating frequency, the second antenna sharing with said first antenna a segment of a conductor; and

a common feed point connected to said first or said second antennas such that said first antenna and said second antenna resonate at said first and second operating frequencies respectively and at least two of said connected antennas configured to have substantially orthogonal polarizations;

wherein the first antenna is a meander line having first and second ends and the second antenna is arranged with an open end partially encircling the first antenna; and

wherein the plurality of connected antennas are formed on a substrate, the first antennas of each of the plurality of connected antennas being connected together at a common connection point at the respective first ends of the first antenna, the plurality of connected antennas so connected being symmetric relative to at least one symmetry axis and wherein the substrate is spaced from a common ground plane.