Antenna structure

1. An antenna structure, comprising:

a first feeding radiation element, coupled to a signal source, wherein the first feeding radiation element has a first slot;

a first grounding radiation element, coupled to a ground voltage, wherein the first grounding radiation element is adjacent to the first feeding radiation element;

a second feeding radiation element, coupled to the signal source, wherein the second feeding radiation element has a second slot;

a second grounding radiation element, coupled to the ground voltage, wherein the second grounding radiation element is adjacent to the second feeding radiation element; and

a nonconductive supporting element, wherein the first feeding radiation element, the first grounding radiation element, the second feeding radiation element, and the second grounding radiation element are disposed on the nonconductive supporting element;

wherein both of the first slot and the second slot are enclosed slots;

wherein the nonconductive supporting element is a 3D (Three Dimensional) structure with a first surface and a second surface which are perpendicular to each other;

wherein the second feeding radiation element and the second grounding radiation element are disposed on the second surface of the nonconductive supporting element.

2. The antenna structure as claimed in claim 1 , wherein the nonconductive supporting element is a planar dielectric substrate.

3. The antenna structure as claimed in claim 1 , wherein the first feeding radiation element and the first grounding radiation element are disposed on the first surface of the nonconductive supporting element.

4. The antenna structure as claimed in claim 1 , wherein the first feeding radiation element has an inverted L-shape.

5. The antenna structure as claimed in claim 1 , wherein the first feeding radiation element comprises a first narrow portion and a first wide portion coupled to each other.

6. The antenna structure as claimed in claim 5 , wherein the first slot is formed in the first wide portion of the first feeding radiation element.

7. The antenna structure as claimed in claim 1 , wherein the first grounding radiation element has a J-shape.

8. The antenna structure as claimed in claim 1 , wherein the first slot has a rectangular shape.

9. The antenna structure as claimed in claim 1 , wherein the second feeding radiation element has an L-shape.

10. The antenna structure as claimed in claim 1 , wherein the second feeding radiation element comprises a second narrow portion and a second wide portion coupled to each other.

11. The antenna structure as claimed in claim 10 , wherein the second slot is formed in the second wide portion of the second feeding radiation element.

12. The antenna structure as claimed in claim 1 , wherein the second grounding radiation element has an inverted J-shape.

13. The antenna structure as claimed in claim 1 , wherein the second slot has a rectangular shape.

14. The antenna structure as claimed in claim 1 , wherein the antenna structure covers a first frequency band and a second frequency band, the first frequency band is from 2400 MHz to 2500 MHz, and the second frequency band is from 5150 MHz to 5850 MHz.

15. The antenna structure as claimed in claim 14 , wherein a length of the first feeding radiation element is equal to 0.25 wavelength of the second frequency band.

16. The antenna structure as claimed in claim 14 , wherein a length of the first grounding radiation element is equal to 0.25 wavelength of the first frequency band.

17. The antenna structure as claimed in claim 14 , wherein a length of the second feeding radiation element is equal to 0.25 wavelength of the second frequency band.

18. The antenna structure as claimed in claim 14 , wherein a length of the second grounding radiation element is equal to 0.25 wavelength of the first frequency band.