Multi-band antenna

Abstract

A multi-band antenna, made by an integral plate and comprises a radiating element, a grounding element, a slit formed as part of the plate, and a feeding line; wherein horizontal conductive portion of said plate are separated from each other with said slit between them and serve as the radiating element and the ground element respectively; the feeding line, comprising an inner conductor connected with the radiating element and an outer conductor connected with the grounding element; wherein said radiating element comprising at least two radiating portions defining at least one radiating arm with gradually increasing width, and at least two radiating portion cooperatively acting to achieve a Ultra Wide Band antenna.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a preferred embodiment of the present invention;

FIG. 2 is a view similar to FIG. 2, but take from a different aspect; and

FIG. 3 is a test chart recording of Voltage Standing Wave Ratio (VSWR) of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to a preferred embodiment of the present invention.

Reference to FIG. 1 to FIG. 2, perspective views of a multi-band antenna 1 in accordance with a preferred embodiment of the present invention are shown.

The multi-band antenna 1 is a planar invert-F antenna 1, and is made by cutting and slitting a plate. The multi-band antenna comprises a radiating element 2, a large-size planar grounding element 3, a slit 4, a feeding line 5 and a protrusion 6. The radiating element 2 and the grounding element 3 are respectively located at the two opposite sides of the slit 4, and one end of the radiating element 2 is connected with the grounding element 3.

The radiating element 2 of the multi-band antenna 1 consists of metal sheets with certain lengths, and connecting with one and another and comprises a first radiating portion 21, a third radiating portion 23 which is connected with the first radiating portion 21 on point P and located in a first plane same as that of the first radiating portion 21, and a second radiating portion 22 vertically extending from the third radiating portion 23 to located in a second plane perpendicular to the first plane. The first radiating portion 21 is a tapered radiating portion and extends from the point P to a first end 210. The width of the first radiating portion 21 is broadened gradually with the length increase from the point P to the first end 210. The second radiating portion 22 firstly extends upward form the joint of the first radiating portion 21 and the third radiating portion 23 to form a first radiating arm 221 whose width is gradually broadened from bottom to up. A second radiating arm 222 with gradually broadened width extends vertically from the first radiating arm 221 in the second plane, and forms a second end 2220. On the joint point of the first radiating arm 221 and the second radiating arm 222, the width of the second radiating arm 222 is narrower than that of the first radiating arm 221. The third radiating portion 23 comprises a rectangle plate 231 defined a third end 230 opposite to the first end 210, and a tapered radiating arm 232. The tapered radiating arm 232 is shown as trapeze shape and extends form the rectangle plate 231 in a direction perpendicular to the rectangle plate 231 to connect with the grounding element 3. The rectangle plate 231 and the tapered radiating arm 232 are respectively located on the two sides of the slit 4 defined between the radiating elements 2 and the grounding element 3. Thus, in this embodiment of the present invention, the first radiating portion 21, the third radiating portion 23, the grounding element 3 and the protrusion 6 are on the first plane and extend toward the grounding element 3, and the second radiating portion 22 is located on the second plane vertical to the first one. The first radiating portion 21 extends along the first plane beyond the grounding element 3.

The grounding element 3 is rectangular shape, and comprises a grounding tab 31. The feeding line 5 comprises an inner conductor 51 and an outer conductor 52. The outer conductor 52 is connected to the grounding tab 31 to form a grounding point. The slit 4 comprises a close groove 41 and an open groove (not graded). The feeding line 5 together with the grounding element 3 and the third radiating portion 23 encircles a close groove 41 on the slit 4. The open groove is formed by the first radiating portion 21, the feeding line 6 and the grounding element 3.

In this embodiment of the present invention, the first radiating portion 21 creates a first frequency resonance whose center frequency is 3.2 GHz. The second radiating portion 22 creates a second frequency resonance whose center frequency is 4.5 GHz. The third radiating portion 23, the grounding element 3 and the close groove 41 jointly create a third frequency resonance whose center frequency is 5.5 GHz. The entire first radiating portion 21, the second radiating portion 22 and the third radiating portion 23 have gradually-increasing-width structure, and this structure is good for impedance match to increase the band width of the radiating portions. So every two frequency bands of the radiating portions are joined to perform an ultra wide band antenna. Reference to FIG. 3, a VSWR chart accordance with this embodiment of the present invention is shown. The multi-band antenna 1 is able to across a frequency band from 2.904 GHz to 6.0 GHz. So the multi-band antenna 1 can meet the demand of the UWB antenna.

In this embodiment of the present invention, the multi-band antenna 1 broadens the band width of the radiating portions through a special structure to make each two frequency bands of the radiating portion joined to achieve a UWB antenna. In manufacturing process, an integer plate is cut and bent to form the multi-band antenna 1. The multi-band antenna 1 has simple structure, conveniently manufacturing process and compact size. In alternative embodiments, the structures of the radiating portions can be not only changed from broad to narrow, but also changed to other shape to adapt to the inner space of the electronic device. And the position of the feeding point and the grounding point can be changed to match impedance.

While the foregoing description includes details which will enable those skilled in the art to practice the invention, it should be recognized that the description is illustrative in nature and that many modifications and variations thereof will be apparent to those skilled in the art having the benefit of these teachings. It is accordingly intended that the invention herein be defined solely by the claims appended hereto and that the claims be interpreted as broadly as permitted by the prior art.

Claims

1. A multi-band antenna, made by an integral plate and comprising: a radiating element;a grounding element;a slit formed as part of the plate, wherein horizontal conductive portion of said plate are separated from each other with said slit between them and serve as the radiating element and the ground element respectively;a feeding line, comprising an inner conductor connected with the radiating element and an outer conductor connected with the grounding element;wherein said radiating element comprising at least two radiating portions defining at least one radiating arm with gradually increasing width, and at least two radiating portions cooperatively acting to achieve a Ultra Wide Band antenna.

2. The multi-band antenna as claimed in claim 1, wherein said radiating element comprises a third radiating portion connected with the grounding element, a first radiating portion extending from the third radiating portion and a second radiating portion extending from the third radiating portion.

3. The multi-band antenna as claimed in claim 2, wherein said first radiating portion with said third radiating portion forms a longwise metal arm, and said slit is between the longwise metal arm and the grounding element.

4. The multi-band antenna as claimed in claim 2, wherein said each radiating portion comprises a gradually-increasing-width radiating arm.

5. The multi-band antenna as claimed in claim 2, wherein said first radiating portion extends from the third radiating portion in a parallel direction and located in the same plane as that of the third radiating portion, said second radiating portion extends from the third radiating portion in a direction perpendicular to the third radiating portion and located in a different plane from that of the third radiating portion.

6. The multi-band antenna as claimed in claim 2, wherein said first radiating portion is a tapered plate, and comprises a protrusion extending from the joint of the first radiating portion and the third radiating portion to connect with said feeding line.

7. The multi-band antenna as claimed in claim 2, wherein said second radiating portion comprising a tapered first radiating portion and a tapered second radiating portion, and the first radiating portion extending from the third radiating portion and the second radiating portion extending from the first radiating portion.

8. The multi-band antenna as claimed in claim 2, wherein said first radiating portion, third radiating portion are on the first plane, and the second radiating portion is located on the plane vertical to the first plane.

9. The multi-band antenna as claimed in claim 2, wherein said first radiating portion extends beyond said grounding element.

10. The multi-band antenna as claimed in claim 9, wherein said third radiating portion comprising a rectangle plate and a tapered radiating arm located on one side of the grounding element opposite to the rectangle plate, and the tapered radiating arm is tapered trapeze shape and extends to connect with the grounding element.

11. The multi-band antenna as claimed in claim 10, wherein said feeding line with the grounding element and the third radiating portion encircles a close groove on the slit.

12. The multi-band antenna as claimed in claim 11, wherein said first radiating portion creates a first frequency resonance, the second radiating portion creates a second frequency resonance, and the third radiating portion, the grounding element and the close groove jointly create a third frequency resonance.

13. The multi-band antenna as claimed in claim 12, wherein said first frequency resonance's center frequency is 3.2 GHz, the second frequency resonance's center frequency is 4.5 GHz, and the third frequency resonance's center frequency is 5.5 GHz.

14. The multi-band antenna as claimed in claim 12, wherein said band width of the multi-band antenna is across 2.904 GHz to 6.0 GHz.

15. A multi-band antenna, made by an integral plate and comprising: a radiating element;a grounding element;a slit formed as part of the plate, comprising a close groove, and wherein horizontal conductive portion of said plate are separated from each other with said slit between them and serve as the radiating element and the ground element respectively;a feeding line, comprising an inner conductor connected with the radiating element and an outer conductor connected with the grounding element;wherein said radiating element comprising at least two radiating portions defining at least one radiating arm with gradually increasing width, and said at least two radiating portion cooperatively acting to achieve a Ultra Wide Band antenna.

16. The multi-band antenna as claimed in claim 15, wherein said radiating element comprises a third radiating portion connected with the grounding element, a first radiating portion extending from the third radiating portion and a second radiating portion extending from the third radiating portion.

17. The multi-band antenna as claimed in claim 16, wherein said close groove is encircled by the feeding line, the grounding element and the third radiating portion.

18. The multi-band antenna as claimed in claim 16, wherein said the slit also comprises an open portion which is differentiated from the close groove.

19. The multi-band antenna as claimed in claim 16, wherein said the open portion is formed by the first radiating portion, the feeding line and the grounding element.

20. A multi-band antenna comprising: an integral plate defining a grounding element and a radiating element thereon;a first slot formed in the plate adjacent to an edge of the plate to separate said grounding element and said radiating element;a point defined on the radiating element, on which a feeding cable is connected and by which a first radiating section and a second radiating section are defined;a third radiating section extending from said edge about said point in an angled manner with regard to the plane defined by said grounding element; anda second slot is formed between the third radiating section; whereinthe first slot and the second slot extends in opposites directions.