Planar antenna in the ISM band with an omnidirectional pattern in the horizontal plane

• US 5,583,510 A
• Filed: 11/16/1994
• Issued: 12/10/1996
• Est. Priority Date: 11/16/1994
• Status: Expired due to Fees

• Current Assignee: Lenovo Singapore Pte Limited (Lenovo Group Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: Gaucher, Brian P., Lanzetta, Alphonso P., Ponnapalli, Saila
• Primary Examiner(s): Hajec, Donald T.
• Assistant Examiner(s): PHAN, THO GIA
• Application Number:
  US08/340,571
• Time in Patent Office: 755 Days
• Field of Search: 343/700 MS, 343/793, 343/795, 343/797
• US Class Current: 343/700.0MS
• 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 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40

Abstract

A multilayer antenna includes a first layer which is a ground plane and which has a plurality of first clearance holes. A first dielectric layer is positioned over the first layer and a second layer is positioned over the first dielectric layer and has a plurality of quarter wave transformers. A second dielectric layer is positioned over the second layer and a third layer ground plane is positioned over the second dielectric layer and has a plurality of second clearance holes for a feed structure. A third dielectric layer is positioned over the third layer and a fourth layer is positioned over the third dielectric layer and has a cross shape. The first and third layers are coupled together via plated-through holes.

Claims

1. A multilayer antenna, comprising:

a first layer being a ground plane and having a plurality of first clearance holes;

a first dielectric layer positioned over said first layer;

a second layer positioned over said first dielectric layer and having a plurality of quarter wave transformers connected to a plurality of transmission lines, each transmission line of said plurality of transmission lines outputting a signal and each said transmission line outputting said signal in phase;

a second dielectric layer positioned over said second layer;

a third layer ground plane positioned over said second dielectric layer and having a plurality of second clearance holes for a feed structure;

a third dielectric layer positioned over said third layer; and

a fourth layer positioned over said third dielectric layer and having a cross shape, said first and third layers being coupled together via said first and second clearance holes,

wherein said fourth layer includes a plurality of feed points for receiving said signal, and

said antenna producing a linearly polarized radiation pattern perpendicular to said fourth layer.

2. A multilayer antenna according to claim 1, wherein said antenna has a doughnut-shaped radiating pattern.

3. A multilayer antenna according to claim 1, wherein said first layer comprises at least one of copper and a copper alloy.

4. A multilayer antenna according to claim 3, wherein said second layer comprises at least one of copper and a copper alloy.

5. A multilayer antenna according to claim 4, wherein said third layer comprises at least one of copper and a copper alloy.

6. A multilayer antenna according to claim 5, wherein said fourth layer comprises at least one of copper and a copper alloy.

7. A multilayer antenna according to claim 1, wherein said antenna has dimensions of 3.8 cm by 3.8 cm and has a thickness of substantially 4.86 mm.

8. A multilayer antenna according to claim 1, wherein said fourth layer includes a plurality of arms thereby forming said cross shape, each of said arms having a width of 1.55 mm.

9. A multilayer antenna according to claim 1, wherein said first and second dielectric layers each have a thickness of 0.031 mils.

10. A multilayer antenna according to claim 1, wherein said third dielectric layer has a thickness of 0.125 mils.

11. A multilayer antenna according to claim 8, wherein ends of said arms are grated and said antenna comprises a single antenna element.

12. A multilayer antenna according to claim 1, wherein said first, second and third dielectric layers each comprise epoxy polyphenylene oxide resin.

13. A multilayer antenna for embedding into a peripheral of a computer system, comprising:

a first layer being a ground plane and having a plurality of first clearance holes;

a first dielectric layer mounted on said first layer;

a second layer mounted on over said first dielectric layer and having a plurality of quarter wave transformers connected to a plurality of transmission lines, each transmission line of said plurality of transmission lines outputting a signal and each said transmission line outputting said signal in phase;

a second dielectric layer mounted on said second layer;

a third layer ground plane mounted on said second dielectric layer and having a plurality of second clearance holes for a feed structure;

a third dielectric layer mounted on said third layer; and

a fourth layer mounted on said third dielectric layer and having a cross shape, said first and third layers being coupled together via plated-through holes,

said first, second, third and fourth layers each comprising at least one of copper and a copper alloy,

wherein said fourth layer includes a plurality of feed points for receiving said signal, and

said antenna producing a linearly polarized radiation pattern perpendicular to said fourth layer.

14. A multilayer antenna according to claim 13, wherein said second layer is coupled to a quarter wave transformer via a line having a predetermined resistance for splitting power to two transmission lines,

said two transmission lines being split using second and third transformers, thereby resulting in a four-way power split,

a length of said transmission lines being equal such that all feed points receive an in phase signal.

15. A multilayer antenna according to claim 14, wherein said fourth layer is a top layer and includes a plurality of feed points for receiving said transmission lines,

said first layer being a bottom layer and including a pad for a surface mount connector at a surface thereof.

16. A multilayer antenna according to claim 15, wherein said antenna has a doughnut-shaped radiating pattern and has dimensions of 3.8 cm. by 3.8 cm. and has a thickness of substantially 4.86 mm and wherein said fourth layer includes a plurality of arms thereby forming said cross shape, each of said arms having a width of 1.55 mm.

17. A multilayer antenna according to claim 16, wherein said first and second dielectric layers each have a thickness of 0.031 mils.

18. A multilayer antenna according to claim 17, wherein said third dielectric layer has a thickness of 0.125 mils.

19. A multilayer antenna according to claim 18, wherein ends of said arms are grated and said antenna comprises a single antenna element.

20. A multilayer antenna according to claim 19, wherein said first, second and third dielectric layers each comprise epoxy polyphenylene oxide resin.