1. Field of the Invention
The present invention relates generally to an antenna, specially, that the antenna is used in an electric device.
2. Description of the Prior Art
A planar inverted-F antenna is always used inside an electric device. For the electric device trending to be small and thin, the antenna inside the electric device should have the feature of small volume. TW Patent No. TW 12040450, issued to Cheng on May 1, 2005, discloses a planar inverted-F antenna. Referencing to FIG. 1 of the patent, the antenna includes a grounding element, a radiating element apart from the grounding element, and a connecting element serving to connect a radiating element and a grounding element. The connecting element includes a plurality of segments. The radiating element includes a plurality of radiating arms. However, all the segments of the connecting element and the radiating arms of the radiating element are arranged on the same plane so as to the antenna is too long.
Hence, in this art, an improved antenna to overcome the above-mentioned disadvantages of the prior art should be provided.
A primary object, therefore, of the present invention is to provide a low-profile antenna with a three-dimensional connecting element.
In order to implement the above object, the multi-band antenna comprises a grounding element having a side edge, a connecting element, and a radiating element. The radiating element is electrically connected to the grounding element via the connecting element, and comprises a first radiating portion and a second radiating portion respectively extending from the connecting element. The connecting element comprises a folded connecting arm extending along three dimensions. A slot is formed between the connecting arm and the grounding element.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of a preferred embodiment when taken in conjunction with the accompanying drawings.
Reference will now be made in detail to a preferred embodiment of the present invention.
Reference to
The supporting portion 10 is made from insulating material and porose structure. The supporting portion 10 has eight surfaces.
The antenna 20 is an inverted-F antenna and made from an integrated metal plate. The antenna 20 is attached on the five surfaces of the supporting portion 10, and comprises a grounding element 21 attached on a lower surface thereof, a connecting element 22 extending upward from the grounding element 21, and a radiating element 23 extending from the connecting element 22.
The grounding element 21 extends along a horizontal panel and comprises a first side edge 210 and a second side edge 212. A metal foil (not shown) is attached on an lower surface of the grounding element 21 so as to make the performance of the antenna 20 better. In other embodiment, the metal foil should be attached on an metal plane inside the electric device.
The connecting element 22 extends from the first side edge 210 of the grounding element 21 and is bent more than two times to form a three-dimensional structure. The connecting element 22 has a first end connected to the grounding element 21 and a second end apart from the grounding element 21. The connecting element 22 comprises a first arm 220 extending from the first side edge 210 of the grounding element 21, an inflectional second arm 222 extending from the first arm 220. The second arm 222 extends in three dimensions and forms U-shaped configuration. The second arm 222 comprises a first segment 2220, a second segment 2222 and a third segment 2224 defining a beginning portion 22242 connected to the second segment 2222 and an end portion 22240 opposite to the beginning portion 22242. The connecting element 22 has a length and a width along a horizontal plane which are respectively no more than a length and a width of the grounding element 21. A slot 24 is formed between the second arm 222 of the connecting element 22 and the grounding element 21. The slot 24 is of U-shaped configuration for adjust the impedance of the antenna 20.
The radiating element 23 comprises a first radiating portion 230 extending upwardly from the end portion 22240 of the third segment 2224 of the connecting element 22 to form a free end 2306, and a second radiating portion 232 extending upwardly from the beginning portion 22242 of the connecting element 22 to form a free end 2326. In this embodiment, the two free ends of the first radiating portion 230 and the second radiating portion 232 extend along the same direction. And in other embodiment, the two ends can also respectively extend along different directions. The first radiating portion 230 is located on the same plane with the third segment 2224 and of L-shaped configuration. The second radiating portion 232 is of tridimensional L-shaped configuration and comprises a first radiating arm 2320 located on the same plane with the third sided arm 2224 of the connecting element 22, and a second radiating arm 2322 extending from the first radiating arm 2320 along a direction perpendicular to the grounding element 21. The first radiating arm 230 is shorter than and below the second radiating portion 232. The first radiating arm 230 is between the second radiating portion 232 and the grounding element 21. The grounding element 21 has substantially a length equal to the second radiating arm 2232. In this embodiment, the first radiating portion 230 is used to receive and send higher frequency band signals, the second radiating portion works on lower frequency band. Referencing to
The feeding line 30 comprises an inner conductor 31 and an outer conductor 32. The inner conductor 31 is connected to the end portion 22240 of the third segment 2224 of the connecting element 22 to form a feeding point 214. The outer conductor 32 is connected to the grounding element 21 to form a grounding point 216. In other embodiment, the feeding point 214 can be moved to other positions to match the impedance of the antenna 20 and driving point impedance.
The supporting portion 10 is designed according to the antenna 20 so that the antenna 20 can be attached on the supporting portion 10. In this embodiment, the grounding element 21 is attached on a lower surface of the supporting portion 10 and the second radiating arm 2322 of the second radiating portion 232 is attached on an upper surface of the supporting portion 10.
It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
Number | Date | Country | Kind |
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97131448 A | Aug 2008 | TW | national |
Number | Name | Date | Kind |
---|---|---|---|
2978703 | Kuecken | Apr 1961 | A |
5936590 | Funder | Aug 1999 | A |
6049314 | Munson et al. | Apr 2000 | A |
6114996 | Nghiem | Sep 2000 | A |
7439935 | Rodenbeck | Oct 2008 | B1 |
Number | Date | Country |
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200962453 | Oct 2007 | CN |
I240450 | May 2005 | TW |
Number | Date | Country | |
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20100039331 A1 | Feb 2010 | US |