Stacked multi-resonator antenna

• US 20060214850A1
• Filed: 03/24/2005
• Published: 09/28/2006
• Est. Priority Date: 03/24/2005
• Status: Active Grant

• Current Assignee: TDK Corporation, TDK Kabushiki Kaisha
• Original Assignee: TDK Corporation
• Inventors: Modro, Joseph, O'Riordan, Pauline
• Granted Patent: US 7,274,334 B2
• Time in Patent Office: Days
• US Class Current: 343/700.MS
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 1/36 Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewithH01Q1/08, H01Q1/14 take precedence
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 1/40 Radiating elements coated with or embedded in protective material
• 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 5/00 Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements combinations of separate active antenna units operating in different wavebands and connected to a common feeder system H01Q21/30
• CPC Class Codes: H01Q 5/357 using a single feed point
• CPC Class Codes: H01Q 5/371 Branching current paths

Abstract

An antenna structure comprising a ground plane, a feed line and at least one resonator element that is embedded in a dielectric substrate and which is meandering in shape such that it includes at least two adjacent resonator segments. As a result, the resonator element resonates in two separate frequency bands. A second resonator element is preferably provided, the second resonator element being dimensioned to resonate in a frequency band located on one side of a third operating frequency band, the feed line and ground plane being arranged to cause a resonance in a frequency band located on the other side of the third operating frequency band. During use, the combined effect of the resonance of the second resonator element and of the feed line and ground plane is to cause the antenna structure to resonate in the third operating frequency band.

Claims

1. An antenna structure comprising at least one resonator element, a ground plane and a feed line, wherein said at least one resonator element is meandering in shape such that said at least one resonator element includes at least two adjacent resonator segments, and wherein said at least one resonator element is embedded in a dielectric substrate such that, when said at least one resonator is excited by a signal in a first operational frequency band, said at least one resonator resonates in said first operational frequency band, and when said at least one resonator is excited by a signal in at least one other operational frequency band, electromagnetic coupling occurs between said at least two adjacent resonator segments and causes said at least one resonator element to resonate in said at least one other operational frequency band.

2. An antenna structure as claimed in claim 1, wherein said at least one resonator element includes a first resonator element, said antenna structure further including a second resonator element, wherein in respect of an operating frequency band of said antenna structure, said second resonator element is dimensioned to resonate in a frequency band located on one side of said operating frequency band, the feed line and ground plane being arranged to cause a resonance in a frequency band located on the other side of said operating frequency band, wherein, during use, the combined effect of the resonance of said second resonator element and of said feed line and ground plane is to cause said antenna structure to resonate in said operating frequency band.

3. An antenna structure as claimed in claim 1, in which said at least one resonator element includes at least one corner section, said at least one corner section being curved.

4. An antenna structure as claimed in claim 1, wherein said at least one resonator element includes a first resonator element, said antenna structure further including a second resonator element, said first and second resonator element having a single, common feed point connected to said feed line, and being dimensioned to serve as respective quarter wavelength resonators for a respective frequency band.

5. An antenna structure as claimed in claim 4, wherein said second resonator element is embedded in said dielectric substrate.

6. An antenna structure as claimed in claim 4, wherein said second resonator element is meandering in shape.

7. An antenna structure as claimed in claim 4, wherein said first resonator element lies in a first plane and said second resonator element lies in a second plane, said first and second planes being substantially parallel with one another.

8. An antenna structure as claimed in claim 1, including a resonator component comprising said at least one resonator element embedded in said dielectric substrate, said at least one resonator element lying in a first plane, said ground plane being spaced apart from said resonator component so that said ground plane does not overlap with said at least one resonator element in a direction substantially perpendicular with said first plane.

9. An antenna structure as claimed in claim 8, wherein said ground plane is substantially parallely disposed with respect to said first plane.

10. An antenna structure as claimed in claim 8, wherein said at least one resonator element has a single feed point and extends from said feed point generally in a first direction, said resonating component being spaced apart from said ground plane in a direction substantially perpendicular with said first direction.

11. An antenna structure as claimed in claim 8, wherein said at least one resonator element has a single feed point and said antenna structure further includes an excitation point located in register with said ground plane, said feed line extending between said excitation point and said feed point.

12. An antenna structure as claimed in claim 11, wherein said at least one resonator element extends from said feed point generally in a first direction, said feed line extending in a direction substantially perpendicular with said first direction.

13. An antenna structure as claimed in claim 11, wherein said feed line comprises a length of transmission line extending substantially the entire distance between the feed point and the excitation point.

14. An antenna structure as claimed in claim 8, provided on a substrate having an obverse surface and a reverse surface, said resonator component and said feed line being provided on said obverse face, said ground plane being provided on said reverse face.

16. A wireless communications device comprising an antenna structure as claimed in claim 1.

15. An antenna structure comprising a ground plane, a feed line, and at least one resonator element, wherein in respect of an operating frequency band of said antenna structure, said at least one resonator element is dimensioned to resonate in a frequency band located on one side of said operating frequency band, the feed line and ground plane being arranged to cause a resonance in a frequency band located on the other side of said operating frequency band, wherein, during use, the combined effect of the resonance of said at least one resonator element and of said feed line and ground plane is to cause said antenna structure to resonate in said operating frequency band.