Printed antenna structure

• US 20030218572A1
• Filed: 05/21/2003
• Published: 11/27/2003
• Est. Priority Date: 05/23/2002
• Status: Active Grant

• Current Assignee: Realtek Semiconductor Corp.
• Original Assignee: Realtek Semiconductor Corp.
• Inventors: Lee, Chih-Min, Chung, Shyh-Jong, Wu, Min-Chuan, Kuo, Peng-Yuan
• Granted Patent: US 6,924,768 B2
• Time in Patent Office: Days
• US Class Current: 343/700MS
• 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 9/0442 with particular tuning means

Abstract

The present invention discloses a printed antenna structure. The printed antenna structure comprises: a dielectric layer having opposed surfaces, a ground plane layer covered on the first surface of the dielectric layer, a feed-line extending over the second surface of the dielectric layer and connecting to a driving circuitry, a primary radiating element connected to the feed-line and not extending over to the ground plane layer, and a tuning element connected to the primary radiating element and not extending over to the ground plane layer for adjusting the radiating frequency. The timing element her comprises two stubs each having a free end spaced apart from each other and a fixed end connected to the primary radiating element so as to reduce the overall length of the printed antenna.

Claims

1. A printed antenna structure, comprising:

a circuit board of dielectric material having a first surface and a second surface which is spaced apart from and substantially parallel to said first surface;

a ground plane layer of electrically conductive material covering a portion of the first surface of the circuit board;

a feed-line of electrically conductive material disposed on the second surface of the circuit board so as to extend over the ground plane layer;

a primary radiating element of electrically conductive material electrically connected to the feed-line and disposed on the second surface so as not to extend over the ground plane layer; and

a tuning element of electrically conductive material electrically connected to the primary radiating element and disposed on the second surface so as not to extend over the ground plane layer;

wherein the tuning element comprises at least two stubs each having a free end spaced apart from each other and a fixed end connected to the primary radiating element.

2. The printed antenna as recited in claim 1, wherein the printed antenna is a Y-shaped monopole printed antenna.

3. The printed antenna as recited in claim 1, wherein the printed antenna is a clamp-shaped monopole printed antenna.

4. The printed antenna as recited in claim 1, wherein the two stubs are both linear.

5. The printed antenna as recited in claim 1, wherein the two stubs are substantially parallel to each other having their fixed ends connected to each other but their free ends spaced apart from each other so as to form a substantially clamp-shaped structure.

6. The printed antenna as recited in claim 1, wherein the two stubs form a V-shaped structure.

7. The printed antenna as recited in claim 1, wherein the primary radiating element is a curved structure with substantially equal width.

8. A structure of tuning element for use with a printed antenna for transmission of a spectrum of electromagnetic waves having a wavelength λ

_g at the center frequency, said printed antenna comprising a primary radiating element and the tuning element electrically connected to one end of the primary radiating element, said primary radiating element having an overall length of L2, said tuning element comprising;

at least two stubs, each having an overall length of L1 and including a free end spaced apart from each other and a fixed end connected to the primary radiating element;

wherein L1+L2<

λ

_g/4.

9. The structure of tuning element as recited in claim 8, wherein the printed antenna further comprises:

a circuit board of dielectric material having a first surface and a second surface which is spaced apart from and substantially parallel to said first surface;

a ground plane layer of electrically conductive material covering a portion of the first surface of the circuit board; and

a feed-line of electrically conductive material connected to the primary radiating element and disposed on the second surface of the circuit board so as to extend over the ground plane layer;

wherein the primary radiating element and the tuning element are both made of electrically conductive material and disposed on the second surface so as not to extend over the ground plane layer.

10. The structure of tuning element as recited in claim 8, wherein the printed antenna is a Y-shaped monopole printed antenna.

11. The structure of tuning element as recited in claim 8, wherein the printed antenna is a clamp-shaped monopole printed antenna.

12. The structure of tuning element as recited in claim 8, wherein the two stubs are both linear.

13. The structure of tuning element as recited in claim 8, wherein the two stubs are substantially parallel to each other having their fixed ends connected to each other but their free ends spaced apart from each other so as to form a substantially clamp-shaped structure.

14. The structure of timing element as recited in claim 8, wherein the two stubs form a V-shaped structure.

15. The structure of tuning element as recited in claim 8, wherein the primary radiating element is a curved structure with substantially equal width.

16. A method for designing a printed antenna structure for transmission of a spectrum of electromagnetic waves having a wavelength λ

_g at the center frequency f₀, wherein

17. The method as recited in claim 16, wherein the printed antenna further comprises:

a circuit board of dielectric material having a first surface and a second surface which is spaced apart from and substantially parallel to said first surface;

a ground plane layer of electrically conductive material covering a portion of the first surface of the circuit board; and

a feed-line of electrically conductive material connected to the primary radiating element and disposed on the second surface of the circuit board so as to extend over the ground plane layer;

wherein the primary radiating element and the tuning element are both made of electrically conductive material and disposed on the second surface so as not to extend over the ground plane layer.

18. The method as recited in claim 16, wherein L1+L2<

λ

_g/4.