Planar antenna

• US 6,275,192 B1
• Filed: 12/29/2000
• Issued: 08/14/2001
• Est. Priority Date: 05/31/2000
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Young-eil
• Primary Examiner(s): PHAN, THO GIA
• Application Number:
  US09/749,915
• Time in Patent Office: 228 Days
• Field of Search: H01/Q.138, 343/700.MS, 343/829, 343/831, 343/846, 343/848
• 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 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

A small planar antenna combined with a printed circuit board (PCB). The planar antenna includes: a dielectric layer with a predetermined thickness; first and second ground layers formed on top and bottom surfaces of the dielectric layer, respectively, corresponding to each other; and a first antenna unit which extends from a side of each of the respective first and the second ground layers, for radiating a first polarized wave with the application of current. A second antenna unit extends from a side of each of the respective first and second ground layers, for radiating a second polarized wave orthogonal to the first polarized wave with the application of current. A feeding stripline is installed between the first and second antenna units, in the dielectric layer, for applying the current to the first and second antenna units, wherein the first and second polarized waves can be separately radiated.

Claims

1. A planar antenna comprising:

a dielectric layer with a predetermined thickness;

a first ground layer formed on a top surface of the dielectric layer;

a second ground layer formed on a bottom surface of the dielectric layer, the first ground layer and the second ground layer corresponding to each other;

a first antenna unit which extends from a side of the first ground layer and a side of the second ground layer, the first antenna unit having a predetermined pattern which radiates a first polarized wave with an application of current;

a second antenna unit which extends from a side of the first ground layer and a side of the second ground layer, the second antenna unit having a predetermined pattern which radiates a second polarized wave orthogonal to the first polarized wave with the application of current; and

a feeding stripline installed between the first and the second antenna units, in the dielectric layer, the feeding stripline applies current to the first and the second antenna units,

wherein the first and the second polarized waves are operative to be separately radiated from the first and the second antenna units, respectively.

2. The planar antenna of claim 1, wherein the first antenna unit comprises:

a first upper radiation pattern having a first upper stub line which extends a length of λ

/4 from an edge of the first ground layer, and a first upper radiation portion which radiates waves and extends from an end of the first upper stub line orthogonal to a longitudinal direction of the first upper stub line; and

a first lower radiation pattern having a first lower stub line which extends a length of λ

/4 from an edge of the second ground layer, corresponding to the first upper stub line, and a first lower radiation portion which radiates waves and extends from an end of the first lower stub line in an opposite direction to the first upper radiation portion.

3. The planar antenna of claim 2, wherein each of the first upper and the first lower radiation portions has a length of less than λ

/4.

4. The planar antenna of claim 2, wherein the first upper radiation portion and the first lower radiation portion, respectively, include a first upper extension disposed at an end of the first upper radiation portion and a first lower extension disposed at an end of the first lower radiation portion, the first upper extension and the first lower extension, respectively, are parallel to the first upper stub line and the first lower stub line and extend a predetermined distance to be respectively closer to the first ground layer and the second ground layer.

5. The planar antenna of claim 4, wherein each of the first upper and the first lower extensions has a length of λ

/25 to λ

/30.

6. The planar antenna of claim 1, wherein the second antenna unit comprises:

a second upper radiation pattern having a second upper stub line which extends a length of λ

/4 from an edge of the first ground layer, and a second upper radiation portion which radiates waves and extends from an end of the second upper stub line orthogonal to a longitudinal direction of the second upper stub line; and

a second lower radiation pattern having a second lower stub line which extends a length of λ

/4 from an edge of the second ground layer, corresponding to the second upper stub line, and a second lower radiation portion which radiates waves and extends from an end of the second lower stub line in an opposite direction to the second upper radiation portion.

7. The planar antenna of claim 6, wherein each of the second upper and the second lower radiation portions has a length of less than λ

/4.

8. The planar antenna of claim 6, wherein the second upper radiation portion and the second lower radiation portion, respectively, include a second upper extension disposed at an end of the second upper radiation portion and a second lower extension disposed at an end of the second lower radiation portion, the second upper extension and the second lower extension, respectively, are parallel to the second upper stub line and the second lower stub line and extend a predetermined distance to be respectively closer to the first ground layer and the second ground layer.

9. The planar antenna of claim 8, wherein each of the second upper and the second lower extensions has a length of λ

/25 to λ

/30.

10. The planar antenna of claim 1, wherein the feeding stripline comprises:

a first branch and a second branch, which power the first and the second antenna units; and

a feeding portion from which the first and the second branches diverge and which is disposed between the first and second ground layers, the feeding portion receives power from a predetermined radio frequency (RF) circuit module and transfers the received power to the first and the second branches.

11. The planar antenna of claim 10, wherein the first and the second branches are arranged perpendicular to each other on a common plane parallel to the first and the second ground layers.

12. The planar antenna of claim 10, wherein the feeding portion is located between a first position, which is on an extension of the first branch close to and perpendicular to the second branch, and a second position, which is on an extension of the second branch close to and perpendicular to the first branch.

13. The planar antenna of claim 12, wherein an angle between the first branch and the feeding portion, and an angle between the second branch and the feeding portion, are the same.

14. The planar antenna of claim 10, wherein the first and the second branches are patterned with a different length to cause a time delay between a generation of waves from the first and the second antenna units, thus generating waves with a phase difference of 90°

.

15. The planar antenna of claim 1, wherein the dielectric layer has a first via hole for applying current through an end of a first branch of the feeding stripline to the first antenna unit, and a second via hole for applying current through an end of a second branch of the feeding stripline to the second antenna unit.

16. The planar antenna of claim 1, wherein the dielectric layer has at least one return via hole for returning a flow of current between the first and second ground layers.

17. The planar antenna of claim 15, wherein the first and the second via holes are filled with a conductive material.

18. The planar antenna of claim 16, wherein the return via hole is filled with a conductive material.