Multi-band internal antenna of symmetry structure having stub

1. A multi-band internal antenna comprising:

a top patch defining a first loop that defines a space therein and a first opening;

a stub provided within the space defined by the first loop, the stub being connected to the top patch by a connector, the stub being configured to expand a bandwidth of a high frequency band in an operating frequency of the antenna;

a bottom patch provided below the top patch and having a first section and a second section connected to a feeder part and a shorting part, respectively, the bottom patch defining a second loop and second and third openings, the second and third openings being provided on opposing sides of the second loop so that the first and second sections of the bottom patch are separated from each other; and

a first connecting part and a second connecting part connecting a first portion and a second portion of the top patch, respectively, to the first section and the second section of the bottom patch to transmit a signal from the bottom patch to the top patch,

wherein the feeder part is configured to provide power to the bottom patch, and the shorting part is configured to ground the bottom patch.

2. The multi-band internal antenna as recited in claim 1 , wherein the connector and the first opening are provided on opposing sides of the first loop, wherein the top patch is bilaterally symmetrical with respect to the connector.

3. The multi-band internal antenna as recited in claim 1 , wherein the first and second sections of the bottom patch are substantially symmetrical.

4. The multi-band internal antenna as recited in claim 3 , wherein the top patch, the stub and the bottom patch comprise substantially the same material.

5. The multi-band internal antenna as recited in claim 3 , wherein a total length of the antenna is defined by the top patch and the first and second sections of the bottom patch, the total length corresponding to a half wavelength of a low frequency band in the operating frequency of the antenna.

6. The multi-band internal antenna as recited in claim 3 , wherein the top patch and the bottom patch are spaced apart vertically by a medium.

7. The multi-band internal antenna as recited in claim 3 , wherein the medium is air or dielectric material.

8. The multi-band internal antenna as recited in claim 3 , wherein the first opening and the second opening are vertically aligned to each other, and the connector and the third opening are vertically aligned to each other.

9. The multi-band internal antenna as recited in claim 8 , wherein the feeder part and the shorting part are spaced apart by the third opening.