CN101102006B - Multi-frequency antenna - Google Patents

Abstract

The invention discloses a multi-frequency antenna, which includes a radiating plate, a grounding plate arranged in parallel with the radiating plate, a resonant cavity obtained by keeping a fixed distance between the radiating plate and the grounding plate, and two conductive sheets; wherein the The radiating plate is roughly in the shape of a "Z" and has a first metal sheet and a second metal sheet extending in different directions. The first conductive sheet extends downward from one side of the first metal sheet as a feed-in end, and the second conductive sheet Extending downward from one side of the second metal sheet and electrically connecting to the ground plate as a ground terminal, the side extending from the first conductive sheet of the first metal sheet is connected to the second extending side of the second metal sheet The sides of the conductive sheets are adjacent to each other.

Description

multi-frequency antenna

【Technical field】

The invention relates to a multi-frequency antenna, in particular to a small flat-panel antenna.

【Background technique】

In modern electronic equipment, the use of wireless communication technology for wireless transmission of data, sound, images, etc. has been more and more used. Antenna, as a component used to induce electromagnetic waves, is a necessary device for the application of wireless communication technology equipment. The early antennas were mostly installed outside the electronic equipment, mainly monopole or helical antennas, which have the characteristics of relatively simple design and high gain coefficient, but these antennas are large in size and installed outside the electronic equipment, and they also require matching The connecting device makes the structure more complicated, and the antenna has a strong directivity. When using it, it is necessary to change the direction of the antenna from time to time to obtain a better reception effect, which also brings inconvenience to the user. With the development of miniaturization, aesthetics and cost reduction of electronic equipment, more and more antennas are built into the electronic equipment. Since the built-in antenna is fixed in the electronic device, the shape and installation method of the built-in antenna need to meet the different requirements of the internal space of different electronic devices. Due to its low height and small volume, the flat-panel antenna is widely used in electronic equipment. In the past, flat-panel antennas were mostly composed of two rectangular plates, one large and one small, and a metal sheet connecting the two rectangular plates. This kind of antenna is often large in size and is not suitable for installation in small electronic devices. In the prior art, as shown in FIG. 1, Taiwan Patent Publication No. TW587847 discloses a miniaturized multi-frequency planar antenna, which includes a signal terminal 21', and the signal terminal 21' is formed by at least one lead wire 42. 'The flat metal surfaces 211', 212' extended from both ends, and the extension piece 41' of a flat metal surface 212' of the signal terminal 21' is used as the feed-in point; a ground terminal 22' is made of metal In the shape of a flat plate, it is arranged parallel to the signal terminal 21'; a resonant cavity 231' is obtained by maintaining a constant predetermined distance between the signal terminal 21' and the ground terminal 22'; and a The above flat metal strips 43' of appropriate length, these flat metal strips 43' are bent into a long section 431' and a short section 432', the long section 431' is parallel to the grounding end 22', and Take the appropriate part of the long section 431' as the feed-in point, the short section 432' is connected to the ground terminal 22', the feed-in point of each signal terminal 21' is connected to the positive pole of the coaxial feeder, and the ground terminal 21 'Connect to the negative pole of the coaxial feeder. The planar antenna can achieve the required impedance matching by adjusting the position, area and shape of the extension piece 41' to match the frequency. In order to make the signal end work at different frequencies, the antenna is provided with at least two feeding points to obtain different The input impedance makes the antenna structure more complicated. And China Taiwan Patent Announcement No. TW 284088 (please refer to shown in Fig. 1 of this patent accompanying drawing) discloses a kind of multi-frequency inverted F planar antenna structure, this antenna provides a kind of miniaturized planar antenna, this antenna utilizes a The ground component is connected to the ground terminal to increase the electrical length of the ground to adjust the impedance of the antenna, thereby ensuring that the antenna has sufficient bandwidth, but the increased ground component makes the structure of the antenna not simple enough. On the other hand, the antenna must be attached to It is fixed on other insulating structures (please refer to Fig. 2 of the accompanying drawings of this patent), and due to the limitation of the internal space of electronic equipment, there is often no suitable space for installing this kind of antenna in some electronic equipment. Therefore, it is really necessary for us to provide a planar multi-frequency antenna that is independent and easy to fix, small in size and simple in structure.

【Content of invention】

The purpose of the present invention is to provide a multi-frequency antenna, especially a flat multi-frequency antenna with simple structure and miniaturization used in electronic equipment.

In order to achieve the above object, the present invention adopts the following technical solutions: a multi-frequency antenna includes a radiation plate, a ground plate arranged in parallel with the radiation plate, a resonant cavity obtained by maintaining a fixed distance between the radiation plate and the ground plate, and two Conductive sheet; wherein the radiation plate is roughly in the shape of a "Z" and has a first metal sheet and a second metal sheet extending in different directions, and the first conductive sheet extends downward from one side of the first metal sheet as a feed-in The second conductive sheet extends downward from one side of the second metal sheet and is electrically connected to the ground plate as a ground terminal. The side of the first metal sheet extending from the first conductive sheet is connected to the second Sides of the metal sheet extending from the second conductive sheet are adjacent to each other.

Compared with the prior art, the multi-frequency antenna of the present invention has the following advantages: the radiating part of the multi-frequency antenna is small in size and easy to fix, and at the same time, the specific position of the conductive sheet on different metal sheets is used to adjust the distance between the feed point and the ground point. position, thereby ensuring the radiation performance of the antenna with a simple structure.

【Description of drawings】

Fig. 1 is a perspective view of the prior art.

Fig. 2 is a perspective view of the multi-frequency antenna of the present invention.

Fig. 3 is an exploded view of the multi-frequency antenna of the present invention.

【Detailed ways】

2 and 3 show a preferred embodiment of the multi-frequency antenna 1 of the present invention. The multi-frequency antenna 1 includes a metal radiating plate 2 and a grounding plate 3 , wherein the radiating plate 2 is roughly in the shape of a “Z” and includes first, second and third rectangular metal sheets 21 , 22 , 23 . Wherein the first metal sheet 21 extends from the starting end 211 to the end 210 along the positive direction of the X axis, the second metal sheet 22 extends from the starting end 211 of the first metal sheet 21 to the end 220 along the positive direction of the Y axis, and the third metal sheet 23 Extend from the radiation plate 2 at a distance from the end 220 to the end 230 along the negative direction of the X-axis. The first metal sheet 21 extends down a first conductive sheet 24 at a certain distance from the starting end 211 , and a second conductive sheet 25 extends downward at a certain distance from the second metal sheet 22 to the end 220 along the negative direction of the Z axis. The ground plate 3 has a plurality of through holes 31 , a slot 32 , an opening 33 formed on one side 30 , a positioning hole 34 , and two rectangular slots 35 . The radiating plate 2 and the grounding plate 3 are arranged separately, and the two keep a fixed distance to form a resonant cavity 4 . In order to better fix the radiating plate 2 and the grounding plate 3 and maintain the relative position between the two, a plastic part 5 is used to separate and fix the radiating plate 2 and the grounding part 3, so as to better fix the radiating plate 2 and the grounding position between section 3. The plastic part 5 has a certain height, the radiation plate 2 is pasted on the upper surface, and several columnar parts 51 are extended from the lower surface along the negative direction of the Z-axis. The through hole 31 is used to fix the plastic part 5 on the ground plate 3 . The plastic part 5 also includes a mounting hole 52 connecting the upper and lower surfaces. The mounting hole 52 communicates with the positioning hole 34 of the grounding part 3 to form a through groove for fixing the plastic part 5, the grounding plate 3 and the multi-frequency antenna 1 on the electronic device. internal. The shape of the plastic part 5 is designed according to the internal structure of the electronic equipment so as to cooperate with the electronic equipment. In this embodiment, the rectangular groove 35 on the ground plate 3 is exposed on both sides of the plastic part 5 . Of course, in other embodiments, the plastic part 5 can also be made of other insulating materials to form an insulating structure, and the plastic part 5 is not an essential component in the antenna, and the plastic part 5 may not be used in other embodiments. The first conductive piece 24 extends through the slot 32 of the ground plate 3 and is not connected to the ground plate 3 , and the second conductive piece extends through the opening 33 of the ground plate 3 . The first conductive sheet 24 is welded with the core wire (not shown) of the feeder to form a feed-in end, and the second conductive sheet 25 is welded with the ground plate 3 to form a ground end.

The radiation plate 2 is the radiation part of the multi-frequency antenna 1, wherein the first metal sheet 21 is used to receive and transmit higher frequency signals (5Ghz), forming the first radiation frequency band; the third metal sheet 23 is used to receive and transmit lower frequency signals. Frequency signal (2GHz), forming the second radiation frequency band. The ground plate 3 serves as a ground for the multi-frequency antenna 1 . For the antenna, its impedance matching degree is an important factor to determine the radiation performance of the antenna, and the distance between the ground terminal and the feed-in terminal directly affects the impedance of the antenna. Due to the requirements of antenna miniaturization and the limitation of installation space, the height of the multi-frequency antenna 1 is reduced, and there is not enough distance between the radiation plate 2 and the ground plate 3 to adjust the distance between the ground terminal and the feed-in terminal to meet the required Therefore, the multi-frequency antenna 1 adjusts the distance between the ground terminal and the feed-in terminal by adjusting the relative positions of the first and second conductive sheets 24 and 25 to achieve the purpose of adjusting the antenna impedance. At the same time, the third metal piece 23 does not extend from the end 220 of the second metal piece 22 , but extends vertically at a certain distance from the end 220 to form a protruding part, which also plays a role in adjusting impedance. In this embodiment, the length of the first metal sheet 21 of the multi-frequency antenna 1 is 9.36mm, and the distance between the first conductive sheet 24 and the starting end 211 of the first metal sheet 21 is 2.00mm; The distance between the first metal sheet 21 is 11.30 mm, and the distance between the second conductive sheet 25 and the end 220 of the second metal sheet 22 is 10.90 mm. The multi-frequency antenna 1 enables the antenna to work in multiple frequency bands at the same time by adjusting the position, length and width of the metal sheet, and the angle coverage is larger, and it also has the effect of impedance matching; in addition, the position of the conductive sheet can be adjusted as needed to adjust the grounding The distance between the end and the feed end can meet the impedance value required by the antenna, so that the antenna radiation performance is better.

Claims (9)

1. a kind of multi-frequency antenna, it comprises radiating plate, the grounding plate that is arranged at intervals in parallel with radiating plate, the resonant cavity that keeps a distance and obtains and two conducting sheets by fixing between radiating plate and grounding plate, it is characterized in that: all The radiation plate is roughly in the shape of a "Z" and has a first metal sheet and a second metal sheet extending in different directions. The first conductive sheet extends downward from one side of the first metal sheet as a feed-in end, and the second conductive sheet The sheet extends downward from one side of the second metal sheet and is electrically connected to the ground plate as a ground terminal. The sides of the two conductive sheets are adjacent to each other, the second metal sheet extends vertically from the first metal sheet, and the radiation plate further includes a third metal sheet extending from the second metal sheet, wherein the first metal sheet The sheet is wider than the second metal sheet, and the third metal sheet is wider than the first metal sheet. 2. The multi-frequency antenna according to claim 1, characterized in that: the third metal sheet of the multi-frequency antenna extends from a distance from the end of the second metal sheet, which is parallel to the first metal sheet, and the second metal sheet is parallel to the first metal sheet. The two metal sheets have a protruding part. 3. The multi-frequency antenna according to claim 1, wherein the first metal sheet is used for transmitting and receiving signals with a frequency of 5 GHz, and the third metal sheet is used for transmitting and receiving signals with a frequency of 2.5 GHz. 4. The multi-frequency antenna according to claim 1, wherein the first conductive sheet forms a certain distance from the start of the first metal sheet, and the second conductive sheet forms a certain distance from the end of the second metal sheet. 5. The multi-frequency antenna according to claim 1, wherein the impedance matching of the antenna is adjusted by adjusting the relative positions of the conductive sheets. 6 . The multi-frequency antenna according to claim 1 , wherein the grounding portion comprises a plurality of through holes, a slot for receiving the conductive sheet, an opening for receiving the conductive sheet, a positioning hole and two rectangular slots. 7. The multi-frequency antenna according to claim 6, wherein the multi-frequency antenna further comprises an insulating structure located between the radiating plate and the grounding plate, and the radiating plate is located on the upper surface of the insulating structure. 8. The multi-frequency antenna according to claim 7, wherein the insulating structure is used to further fix the relative positions of the radiation plate and the ground plate. 9. The multi-frequency antenna as claimed in claim 8, characterized in that: the insulating structure is a plastic part, the shape of the plastic part is designed according to the internal structure of the electronic device, and there are a number of contacts with the grounding part. The column part fitted with the through hole and the installation hole communicated with the positioning hole of the ground part.

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