CN102244318A - Multi-frequency antenna - Google Patents

Abstract

A multi-frequency antenna, which includes a ground metal sheet with an edge and a grounding point, a radiation metal sheet above the ground metal sheet, a short-circuit metal arm between the radiation metal sheet and the ground metal sheet, and a transmission A coaxial transmission line that is signal and includes a center conductor and an outer ground conductor. The radiating metal sheet works in the first working frequency band, and the connecting metal arm works in the second working frequency band. One end of the short-circuit metal arm is connected to one end of the radiating metal sheet, and the other end is connected to the short-circuit point on the edge. The central wire is connected to the radiating metal sheet or the short-circuit metal arm, and the outer layer grounding conductor is connected to the grounding point. A capacitor is also provided between the radiation metal sheet and the short-circuit metal arm. The multi-frequency antenna of the invention has the advantages of convenient adjustment of working frequency band, small size, simple structure and cost saving.

Description

multi-frequency antenna

【Technical field】

The invention relates to a multi-frequency antenna, in particular to a multi-frequency antenna applied to mobile electronic equipment.

【Background technique】

With the rapid development of wireless networks in recent years, the performance requirements of antennas have also gradually increased. The built-in type integrated in electronic equipment not only requires the reduction of size, but also must have the characteristics of built-in type, integration and multi-band. , to be competitive in the market.

At present, there are some commonly used dual-frequency inverted F-shaped antenna designs for electronic communication products suitable for wireless networks. These antennas usually include a first radiating arm, a second radiating arm, a short-circuit metal arm, a ground plate and a feeder , wherein the first radiating arm and the second radiating arm are connected to one end of the short-circuiting metal arm and extend to both sides in opposite directions, the other end of the short-circuiting metal arm is connected to the ground sheet, and the feeder is connected to the feed point on the short-circuiting metal arm , the signal is introduced from the feed point to make the first radiating arm and the second radiating arm realize the first and second working frequency bands. However, such an antenna has a large size, and once designed, the working frequency band is fixed. If the frequency band is changed, the antenna must be redesigned, which wastes cost.

Therefore, it is necessary to provide a multi-frequency antenna that overcomes the above-mentioned problems.

【Content of invention】

The main purpose of the present invention is to provide a multi-frequency antenna with adjustable working frequency band and small size.

To achieve the above object, the present invention adopts the following technical solutions: a multi-frequency antenna, which includes a grounding metal sheet with an edge and a grounding point, a radiating metal sheet above the grounding metal sheet, The short-circuit metal arm between the metal sheets and the coaxial transmission line used to transmit the signal and includes the central conductor and the outer ground conductor. The radiating metal sheet works in the first working frequency band, and the connecting metal arm works in the second working frequency band. One end of the short-circuit metal arm is connected to one end of the radiating metal sheet, and the other end is connected to the short-circuit point on the edge. The central wire is connected to the radiating metal sheet or the short-circuit metal arm, and the outer layer grounding conductor is connected to the grounding point. A capacitor is also provided between the radiation metal sheet and the short-circuit metal arm.

In order to achieve the above object, the present invention can also adopt the following technical solutions: a multi-frequency antenna, which includes a grounded metal sheet, a first radiation arm that is spaced from the grounded metal sheet and has a first radiation arm parallel to the grounded metal sheet, and a first radiation arm perpendicular to the grounded metal sheet. The radiating metal sheet of the second radiating arm, the short-circuiting metal arm connecting the second radiating arm and the grounding metal sheet. The short-circuit metal arm includes a first arm vertically connected to one end of the second radiating arm, an L-shaped second arm connected to the other end of the first arm, and an L-shaped third arm connected to the second arm and the ground metal sheet. The multi-frequency antenna further includes a variable capacitor located between the second radiating arm and the third arm.

Compared with the prior art, the multi-frequency antenna of the present invention is convenient to adjust the working frequency band, has small size, simple structure and saves cost.

【Description of drawings】

FIG. 1 is a three-dimensional assembly diagram of the multi-frequency antenna of the present invention.

Fig. 2 is a partial enlarged view of the capacitor of the multi-frequency antenna of the present invention.

Fig. 3 is a test record diagram of the voltage standing wave ratio frequency function of the multi-frequency antenna of the present invention.

【Detailed ways】

As shown in FIGS. 1 and 2 , the multi-frequency antenna 1 of the present invention includes a grounding metal sheet 10, a radiating metal sheet 11 positioned above the grounding metal sheet 10 and spaced therebetween, and a metal sheet between the grounding metal sheet 10 and the radiating metal sheet 11. The short-circuit metal arm 12 , the capacitor 13 located between the radiating metal sheet 11 and the short-circuit metal arm 12 , the assembly part 14 and the coaxial transmission line 15 arranged at intervals from the radiating metal sheet 11 and the short-circuit metal arm 12 .

The grounding metal sheet 10 is an elongated metal sheet having an edge 101 and a grounding point 103 . The edge 101 is provided with a short-circuit point 102 . The short-circuiting metal arm 12 vertically extends upward from the short-circuit point 102 . The radiating metal sheet 11 extends from the other end of the short-circuiting metal arm 12 and includes a first radiating arm 111 parallel to the grounding metal sheet 10 and a second radiating arm 112 located below the first radiating arm 111 and on the same plane as the short-circuiting metal arm 12 , the first radiating arm 111 and the second radiating arm 112 are perpendicular to each other and both are rectangular metal sheets, and the length of the second radiating arm 112 is shorter than that of the first radiating arm 111 . The short-circuit metal arm 13 is a stepped metal sheet, which includes a rectangular first arm 121 vertically connected to the second radiating arm 112, an L-shaped second arm 122 vertically connected to the first arm 121, and a second L-shaped arm 122 vertically connected to the second radiating arm 112. The L-shaped third arm 123 of the arm 122 , the other end of the third arm 123 is vertically connected to the short-circuit point 102 . A feeding point 124 is disposed on the first arm 121 , and the feeding point 124 may also be disposed on the radiating metal arm 11 . The second arm 122 includes a first arm 1221 vertically connected to the first arm 121 and a second arm 1222 perpendicular to the first arm 1221 . The third arm 123 includes a third arm 1231 vertically connected to the second arm 1222 and a fourth arm 1232 vertically connected to the third arm 1231, the other end of the fourth arm 1232 is connected to the short-circuit point 102, and the first arm 1221, The third arms 1231 are parallel to the second radiating arms 112 . The second radiating arm 112 , the first arm 121 , the second arm 122 , and the third arm 1231 of the third arm 123 together form a gap 16 . In this embodiment, the capacitor 13 is a variable capacitor, one end of which is connected to the free end of the second radiating arm 112 , and the other end is connected to the third arm 1231 of the third arm 123 . However, in other implementation manners, the position of the capacitor 13 can also be changed as required, for example, move along the second radiating arm 112 , and the capacitor 13 can also be other capacitive components. The assembly portion 14 includes a support portion 141 vertically extending upward from one end of the ground metal sheet 10 and a locking portion 142 vertically extending outward from the other end of the support portion 141 and having a circular positioning hole. The locking part 142 is used for assembling the multi-band antenna 1 into the electronic device. The coaxial transmission line 15 is used for signal transmission, and includes a central wire 151 connected to the feeding point 124 of the radiating metal sheet 11 or the shorting metal arm 12 and an outer ground conductor 152 connected to the grounding point 103 of the grounding metal sheet 10 .

As shown in FIG. 3 , it is a voltage standing wave ratio diagram of the multi-frequency antenna 1 of the present invention when the capacitance values of the capacitor 13 are respectively 0pF, 1.0pF, and 2.0pF. The radiating metal sheet 11 works in a lower first operating frequency band, the short-circuit metal arm 12 works in a higher second operating frequency band, and when the capacitor 13 is increased from 0pF to 1.0pF, the first operating frequency band shifts to the left, and the capacitor When 13 continues to increase to 2.0pF, the first and second operating frequency bands are shifted to the left. This design can reduce the size of the radiation metal sheet 11, and adjust the first and second frequency bands by adjusting the value of the capacitor 13 according to different needs. Two working frequency bands, saving cost and equipment space.

In this embodiment, the grounding metal sheet 10, the radiating metal sheet 11 and the short-circuiting metal arm 12 can be made by stamping or cutting a single metal sheet, or the radiating metal sheet 11 and the short-circuiting metal arm 12 It is formed on a microwave substrate by printing or etching, and then connected to the ground metal sheet 10 . The capacitor 13 is welded on the second radiating arm 112 and the third arm 1231 of the short-circuit metal arm 12 , or fixed on the multi-frequency antenna 1 by locks, screws and other means.

Claims (10)

1. A multi-frequency antenna, comprising a ground metal sheet with an edge and a grounding point, a radiation metal sheet above the ground metal sheet, a short-circuit metal arm between the radiation metal sheet and the ground metal sheet, and A coaxial transmission line that transmits signals and includes a central conductor and an outer layer ground conductor is characterized in that: the radiating metal sheet works in the first working frequency band, the connecting metal arm works in the second working frequency band, and the short-circuiting metal arm One end is connected to one end of the radiating metal sheet, the other end is connected to a short-circuit point located at the edge, the central conductor is connected to the radiating metal sheet or the short-circuiting metal arm, the outer layer grounding conductor is connected to the grounding point, and the radiating metal sheet is connected to the short-circuiting metal arm. A capacitor is also arranged between the short-circuit metal arms. 2. The multi-frequency antenna according to claim 1, wherein the radiating metal sheet includes a first radiating arm parallel to the grounding metal sheet and a second radiating arm positioned on the same plane as the short-circuiting metal arm, the first radiating The arm and the second radiating arm are perpendicular to each other and both are rectangular metal sheets, and the length of the second radiating arm is shorter than that of the first radiating arm. 3. The multi-frequency antenna according to claim 2, characterized in that: the short-circuit metal arm is stepped, which includes a rectangular first arm vertically connected to the second radiating arm, an L-shaped second arm, and an L-shaped arm. The third arm, the second arm includes a horizontally extending first arm vertically connected to the first arm and a vertically extending second arm, the first arm and the second arm are coplanar and perpendicular to each other, the first arm and the second arm are coplanar and perpendicular to each other. The three arms include a third arm vertically connected to the second arm and a fourth arm vertically connected to the third arm, and the other end of the fourth arm is vertically connected to the short-circuit point. 4. The multi-frequency antenna according to claim 3, wherein the capacitor is a variable capacitor, one end of which is welded to the free end of the second radiating arm, and the other end is welded to the connecting metal arm the third arm. 5. The multi-frequency antenna according to claim 4, wherein a feed-in point is provided on the first arm of the short-circuit metal arm, and the first working frequency band is lower than the second working frequency band. 6. The multi-frequency antenna according to claim 1 or 5, wherein the grounding metal sheet, the radiating metal sheet and the shorting metal arm are stamped or cut from a single metal sheet. 7. The multi-frequency antenna according to claim 1 or 5, wherein the radiation metal sheet and the short-circuit metal arm are formed on a microwave substrate by printing or etching technology. 8. A multi-frequency antenna, comprising a ground metal sheet, a radiation metal sheet spaced apart from the ground metal sheet and having a first radiation arm parallel to the ground metal sheet and a second radiation arm perpendicular to the ground metal sheet, connected to the second radiation arm The short-circuit metal arm of the two radiating arms and the grounding metal sheet is characterized in that: the short-circuiting metal arm includes a first arm vertically connected to one end of the second radiating arm, an L-shaped second arm connected to the other end of the first arm, and The second arm is connected to the L-shaped third arm of the ground metal sheet, and the multi-frequency antenna further includes a variable capacitor located between the second radiating arm and the third arm. 9. The multi-frequency antenna according to claim 8, wherein the second arm has a first arm parallel to the second radiation arm and a second arm perpendicular to the first arm, and the third arm has A third arm parallel to the second radiating arm and a fourth arm perpendicular to the third arm. 10. The multi-frequency antenna according to claim 9, wherein the second radiating part and the connecting metal arm are located on the same plane.

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