Communication device

1. A communication device, comprising:

a first antenna element;

a second antenna element;

a third antenna element;

a fourth antenna element;

a fifth antenna element;

a sixth antenna element;

a seventh antenna element;

an eighth antenna element; and

a PCB (Printed Circuit Board), having a first side and a second side opposite to each other;

wherein at least one of the first antenna element, the second antenna element, the third antenna element, the fourth antenna element, the fifth antenna element, the sixth antenna element, the seventh antenna element, and the eighth antenna element is adjacent to the first side of the PCB;

wherein the other(s) of the first antenna element, the second antenna element, the third antenna element, the fourth antenna element, the fifth antenna element, the sixth antenna element, the seventh antenna element, and the eighth antenna element is/are adjacent to the second side of the PCB;

wherein a first angle is formed between the first antenna element and the fifth antenna element, and the first angle is from 10 to 30 degrees; or

wherein a second angle is formed between a normal direction of the PCB and each of the second antenna element and the sixth antenna element, and the second angle is from 15 to 25 degrees; or

wherein a third angle is formed between a normal direction of the PCB and each of the third antenna element, the fourth antenna element, the seventh antenna element, and the eighth antenna element, and the third angle is from 15 to 25 degrees.

2. The communication device as claimed in claim 1 , wherein the communication device provides an almost omnidirectional radiation pattern.

3. The communication device as claimed in claim 1 , wherein the first antenna element, the second antenna element, the third antenna element, and the fourth antenna element are adjacent to the first side of the PCB, and wherein the fifth antenna element, the sixth antenna element, the seventh antenna element, and the eighth antenna element are adjacent to the second side of the PCB.

4. The communication device as claimed in claim 1 , wherein at least one of the third antenna element and the fourth antenna element is positioned between the first antenna element and the first side of the PCB.

5. The communication device as claimed in claim 1 , wherein each of the first antenna element, the second antenna element, the third antenna element, the fourth antenna element, the fifth antenna element, the sixth antenna element, the seventh antenna element, and the eighth antenna element is a dipole antenna.

6. The communication device as claimed in claim 1 , wherein the communication device covers a first frequency band, a second frequency band, and a third frequency band.

7. The communication device as claimed in claim 6 , wherein the first antenna element and the fifth antenna element are excited to generate the first frequency band, the second frequency band, and the third frequency band.

8. The communication device as claimed in claim 6 , wherein the second antenna element, the sixth antenna element, and the seventh antenna element are excited to generate the second frequency band and the third frequency band.

9. The communication device as claimed in claim 6 , wherein the third antenna element, the fourth antenna element, and the eighth antenna element are excited to generate the third frequency band.

10. The communication device as claimed in claim 1 , wherein the first antenna element, the second antenna element, the third antenna element, the fourth antenna element, the fifth antenna element, the sixth antenna element, the seventh antenna element, and the eighth antenna element are all deflected with respect to the PCB.

11. The communication device as claimed in claim 6 , wherein each of the first antenna element and the fifth antenna element comprises:

a first radiation element, coupled to a first feeding point; and

a second radiation element, coupled to a first grounding point, wherein the second radiation element and the first radiation element substantially extend in opposite directions.

12. The communication device as claimed in claim 11 , wherein a length of each of the first radiation element and the second radiation element is substantially equal to 0.25 wavelength of the first frequency band.

13. The communication device as claimed in claim 6 , wherein each of the second antenna element, the sixth antenna element, and the seventh antenna element comprises:

a third radiation element, coupled to a second feeding point; and

a fourth radiation element, coupled to a second grounding point, wherein the fourth radiation element and the third radiation element substantially extend in opposite directions.

14. The communication device as claimed in claim 13 , wherein a length of each of the third radiation element and the fourth radiation element is substantially equal to 0.25 wavelength of the second frequency band.

15. The communication device as claimed in claim 6 , wherein each of the third antenna element, the fourth antenna element, and the eighth antenna element comprises:

a fifth radiation element, coupled to a third feeding point; and

a sixth radiation element, coupled to a third grounding point, wherein the sixth radiation element and the fifth radiation element substantially extend in opposite directions.

16. The communication device as claimed in claim 15 , wherein a length of each of the fifth radiation element and the sixth radiation element is substantially equal to 0.25 wavelength of the third frequency band.

17. The communication device as claimed in claim 1 , wherein the PCB comprises a first layer board and a second layer board parallel to each other.