Antenna with U-shaped portion and extending section

1. An antenna for transmitting a wireless signal, comprising:

a ground element;

a short element, connected to the ground element;

a transmitting element, connected to the short element, wherein the transmitting element comprises a U shaped portion and an extending section, and the U shaped portion comprises a first section, a second section and a third section, wherein a first groove is formed between the first section and the second section, and a second end of the first section is connected to the short element, and a first end of the first section is connected to the third section, and a first end of the second section is connected to the third section, and a second end of the second section is a free end of the transmitting element, and a first end of the extending section is connected to the third section, and a second end of the extending section is an extending free end of the transmitting element, wherein a second groove is formed between the first section and the extending section;

a ground point, wherein the ground point is located on the short element; and

a feed point, wherein the feed point is adjacent to the free end of the second section;

wherein the U shaped portion composes a loop antenna unit arranged such that a current travels from the ground point, passing the first section, the third section and the second section, along the first groove to the feed point, and

wherein the first section and the extending section compose an open stub unit arranged such that the current travels from the ground point, passing the first section and the extending section, along the second groove to the extending free end.

2. The antenna as claimed in claim 1 , wherein the ground point is adjacent to a connection point where the short element is connected to the transmitting element.

3. The antenna as claimed in claim 1 , wherein the extending section extends toward the short element.

4. The antenna as claimed in claim 3 , wherein a gap is formed between the extending free end of the extending section and the short element, and the extending free end of the extending section is coupled to the short element.

5. The antenna as claimed in claim 4 , wherein the gap is between 0.03λ˜0.05λ, and λ is a wave length of a wireless signal.

6. The antenna as claimed in claim 1 , wherein the ground element is located on a first plane, the transmitting element is located on a second plane, the first plane is parallel to the second plane, and a distance is formed between the first plane and the second plane.

7. The antenna as claimed in claim 6 , wherein the short element is perpendicular to the ground element.

8. An antenna for transmitting a wireless signal, comprising:

a ground element;

a short element, connected to the ground element;

a transmitting element, connected to the short element, wherein the transmitting element is a three toe claw shaped structure comprising a first section, a second section and an extending section, wherein a second end of the first section is connected to the short element, and a first end of the first section is connected to first ends of the second section and the extending section, and a first groove is formed between the first section and the second section, and a second groove is formed between the first section and the extending section;

a ground point, wherein the ground point is located on the short element; and

a feed point, wherein the feed point is adjacent to a second end of the second section;

wherein the first section and the second section composes a loop antenna unit arranged such that a current travels from the ground point, passing the first section and the second section, along the first groove to the feed point, and

wherein the first section and the extending section compose an open stub unit arranged such that the current travels from the ground point, passing the first section and the extending section, along the second groove to a second end of the extending section.

9. The antenna as claimed in claim 8 , wherein the ground point is adjacent to a connection point where the short element is connected to the transmitting element.

10. The antenna as claimed in claim 8 , wherein the extending section extends toward the short element.

11. The antenna as claimed in claim 10 , wherein a gap is formed between the second end the extending section and the short element, and the second end of the extending section is coupled to the short element.

12. The antenna as claimed in claim 11 , wherein the gap is between 0.03λ˜0.05λ, and λ is a wave length of a wireless signal.

13. The antenna as claimed in claim 8 , wherein the ground element is located on a first plane, the transmitting element is located on a second plane, the first plane is parallel to the second plane, and a distance is formed between the first plane and the second plane.

14. The antenna as claimed in claim 13 , wherein the short element is perpendicular to the ground element.