CN107978838A - Base station antenna and high-low frequency oscillator coaxial mounting platform - Google Patents

Abstract

The invention provides a high-low frequency oscillator coaxial mounting platform which comprises a mounting seat and an isolation reflector plate arranged on the mounting seat, wherein the isolation reflector plate is in a cross shape and comprises a central part and extension parts extending from four directions of the periphery of the central part, the extension parts extend upwards in an inclined mode, and an included angle is formed between the plane where the extension parts are located and the plane where the central part is located. The basic shape of the coaxial mounting platform of the high-frequency and low-frequency oscillators is an upwards bent cross-shaped sheet, low-frequency cross-polarized electromagnetic waves are converted into low-frequency main polarized electromagnetic waves through the coaxial mounting platform of the high-frequency and low-frequency oscillators, and meanwhile, the high-frequency and low-frequency electromagnetic waves are isolated; the axial propagation distance of the wave beam radiated by the high-frequency oscillator after being reflected by the cross extension part tends to be consistent, so that larger gain is realized, low-frequency orthogonal mode conversion and high-frequency gain promotion are achieved, the high-frequency reflector is a high-frequency reflector, has the functions of isolating the low-frequency oscillator and improving high-frequency wave beam dispersion, and is a low-frequency polarization separation piece, and has the functions of improving low-frequency cross polarization discrimination and promoting low-frequency gain.

Description

Base station antenna and high and low frequency vibrator coaxial installation platform

【Technical field】

The invention relates to the field of communication, in particular to a base station antenna which improves the coaxial installation of high and low frequency vibrator cross polarization and gain.

【Background technique】

As a key front-end component of the wireless communication system, the performance of the antenna plays a decisive role in the quality of the operator's network. In recent years, with the rapid increase in the number of mobile users, the communication system is constantly being updated and expanded, and higher and higher requirements are placed on the design of the antenna. On the one hand, the antenna is required to be wide-band and multi-frequency, so as to meet the needs of multiple systems at the same time. Communication requirements; on the other hand, it is required to achieve multi-system sharing and reduce the number of antennas to reduce interference between antennas and reduce costs.

Coaxial installation of high and low frequency oscillators, that is, high and low frequency nested array method in which high frequency oscillators are installed on the central axis of a specially designed radiator with a frame structure and low frequency oscillators with more space in the center. As shown in Figure 1, it has become a widely used method for reducing the size and increasing the gain of multi-frequency antennas. Figure 1 is a schematic diagram of the coaxial array of high and low frequency vibrators 101 and 102 widely used in compact base station antennas: the low frequency vibrator 101 is designed to be a frame structure with an empty middle and relies on surrounding metal strips or sheet metal frames for radiation, while the high The high-frequency vibrator 102 is raised by the mounting base 103 and installed on the central axis of the low-frequency vibrator, hence the name of the coaxial array. Although it saves space, a prominent problem of the coaxial array is the serious interaction between the high-frequency oscillator and the low-frequency oscillator: on the one hand, the high-frequency oscillator above the central axis changes the polarization mode of the lower low-frequency oscillator, resulting in a low-frequency positive On the other hand, after the high-frequency electromagnetic wave is scattered by the low-frequency oscillator, the radiation pattern diverges, and the half-power angle fluctuates significantly with frequency. , the high-frequency vibrator is interfered by the surrounding scattering and resonance, and the radiation pattern is severely dispersed, causing the half-power angle at some frequencies to be seriously large, the gain drops sharply, and the beam deformation is serious, while the half-power angle at other frequencies is seriously small. The signal coverage requirements cannot be met.

The current technical means can only solve the cross-polarization deterioration of the low-frequency oscillator alone, or the half-power angle divergence of the high-frequency oscillator, but cannot simultaneously solve the above-mentioned mutual interference problem caused by the coaxial installation of the high-frequency oscillator and the low-frequency oscillator. For example, to reduce the low-frequency cross-polarization component and enhance the polarization isolation of the low-frequency vibrator, thereby improving the cross-polarization discrimination rate, a polarization separator 202 can be installed on the central axis of the vertical low-frequency vibrator 201, as shown in Figures 2 and 3, Therefore, the phase centers of the main polarization component and the cross polarization component tend to be consistent. The polarization spacer 202 is a cross-shaped metal sheet, the angle between the direction of the cross and the positive and negative polarization directions is 45°, and part of the cross-polarization component incident on the polarization spacer is transformed into The main polarization component, the other part is canceled by the resonant electric field. In order to improve the polarization isolation effect, as shown in FIG. 3 , a plurality of notches 203 are cut at the edge of the cross-shaped sheet, so as to extend the current path and induce more resonances.

To reduce the scattering of high-frequency electromagnetic waves on the surface of the low-frequency vibrator, as shown in Figure 4, the current solution is to insert a reflector 302 between the coaxially placed high-frequency vibrator 301 and the low-frequency vibrator. The reflector thus separates the high and low frequency oscillators in the vertical direction. Thereby reducing the scattering of high-frequency electromagnetic waves on the surface of the low-frequency vibrator.

However, when the low-frequency polarization separator and the high-frequency reflector are applied to the high- and low-frequency oscillators installed coaxially, it is difficult to play an effective role due to the complex electromagnetic interaction between the two. The two technical means of low-frequency vibrator plus polarization spacer and high-frequency vibrator plus reflector are in conflict with each other: low-frequency vibrator plus polarization spacer is easy to induce high-frequency resonance and make high-frequency problems worse; while high-frequency vibrator plus reflector This increases low-frequency scattering, which exacerbates the low-frequency cross-polarization problem.

【Content of invention】

The purpose of the present invention is to provide a base station antenna and a high-low frequency oscillator coaxial installation platform that can solve the cross-polarization deterioration of the low-frequency oscillator, the half-power angle divergence of the high-frequency oscillator, and solve the problem of mutual interference caused by the coaxial installation of the high- and low-frequency oscillators.

In order to realize the object of the present invention, the following technical solutions are provided:

The present invention provides a high-low frequency vibrator coaxial installation platform, which includes a mounting seat, and an isolation reflection sheet arranged on the installation seat. The isolation reflection sheet is in the shape of a cross, including a central part, and a Four extensions extending in four directions, the extensions extend obliquely upward, and there is an angle between the plane where the extension is located and the plane where the central part is located.

The basic shape of the high-low frequency vibrator coaxial installation platform of the present invention is an upwardly bent cross-shaped sheet, and the low-frequency cross-polarized electromagnetic waves are converted into low-frequency main polarized electromagnetic waves by the present invention, and at the same time, the present invention realizes the isolation of high- and low-frequency electromagnetic waves ; Furthermore, the beams radiated by the high-frequency vibrator tend to have the same axial propagation distance after being reflected by the cross extension, thereby achieving greater gain. The coaxial installation platform for high and low frequency oscillators of the present invention has both low frequency orthogonal mode conversion and high frequency gain enhancement. The installation platform is not only a high frequency reflector, but also has the function of isolating low frequency oscillators and improving high frequency beam dispersion, and is also a low frequency polarization The separator has the function of improving low-frequency cross-polarization discrimination and increasing low-frequency gain.

Preferably, the angle between the extension direction of the extension part and the polarization direction of the vibrator is 45°. When the electromagnetic wave radiated by the low-frequency vibrator is incident on the cross reflective surface, the phase centers of the main polarization and cross-polarization components are synchronized by the induced current flowing through the center of the cross, so that the low-frequency cross-polarization is improved and the gain is also improved. .

Preferably, the included angle between the plane where the extension part is located and the plane where the central part is located ranges from 0° to 90°.

Preferably, the extension part extends obliquely upward, and the angle between the plane where the extension part is located and the plane where the central part is located is 30°. This angle is the result of optimization by electromagnetic field simulation software, which not only enhances the reflection of high-frequency electromagnetic waves, reduces the scattering on the surface of high-frequency oscillators, but also does not make the scattering cross-section too large to affect low-frequency cross-polarization.

Preferably, the extending part is in a convex shape, including a base directly connected to the central part and a protruding part extending from the outer edge of the base. On the one hand, the low-frequency resonance is enhanced, and on the other hand, the occurrence of high-frequency resonance is suppressed, thereby avoiding the negative impact on the high-frequency oscillator.

Preferably, the central part is square.

Preferably, the side length L of the central part is 60mm±5mm.

Preferably, a height H of the extending portion extending from the central portion is 18mm±5mm.

Preferably, the width L1 of the protruding part is 50 mm±5 mm, and the height H1 of the protruding part extending from the base is 5 mm±1 mm.

The present invention also provides a base station antenna, which includes a high-frequency vibrator and a low-frequency vibrator coaxially arranged, and the above-mentioned high-low frequency vibrator coaxial installation platform, the high-low frequency vibrator coaxial installation platform is arranged on the low-frequency vibrator Among them, the high-frequency vibrator is arranged on the coaxial installation platform of the high-low frequency vibrator.

The invention solves the serious interactive interference that occurs when the high and low frequency vibrator of the base station antenna is coaxially installed, and is especially suitable for the coaxial installation of the 698-960MHz low-frequency four-lobe vibrator and the 1710-2690MHz high-frequency vibrator, and is useful for improving antenna gain and overcoming cross polarization It has considerable value; in addition, the invention has a simple structure, can be manufactured through basic sheet metal technology, has low cost, and is suitable for mass production.

Compared with the prior art, the present invention has the following advantages:

The basic shape of the high and low frequency vibrator coaxial installation platform of the present invention is an upwardly bent cross-shaped sheet, and the cross-shaped extension part is bent upward by 30°, thereby reducing the influence of scattered current from the surface of the surrounding low-frequency vibrator; further, the high-frequency After the wave beams radiated by the vibrator are reflected by the cross extension part, the axial propagation distance tends to be consistent, thereby achieving greater gain. The coaxial installation platform for high and low frequency oscillators of the present invention has both low frequency orthogonal mode conversion and high frequency gain enhancement. The installation platform is not only a high frequency reflector, but also has the function of isolating low frequency oscillators and improving high frequency beam dispersion, and is also a low frequency polarization The separator has the function of improving low-frequency cross-polarization discrimination and increasing low-frequency gain.

The invention integrates the two functions of the low-frequency electromagnetic wave polarization mode separator and the high-frequency electromagnetic wave reflector into one component for the first time, which not only fully exerts the above functions, but also avoids the mutual interference between the two, and solves the problem of coaxial installation of high and low frequency vibrator Problem: The coaxial installation platform of the high and low frequency oscillators of the present invention is easy to manufacture, low in cost, easy to install, and suitable for batch deployment in base station antennas.

【Description of drawings】

Fig. 1 is a schematic diagram of nested arrays coaxially installed with high and low frequency vibrators in the prior art;

Fig. 2 is a schematic diagram of setting a low-frequency polarization spacer in a low-frequency vibrator in the prior art;

Fig. 3 is a schematic diagram of the polarization direction of the low-frequency polarization spacer in the prior art;

Fig. 4 is a schematic diagram of setting a reflector under the high-frequency vibrator in the prior art;

Fig. 5 is a schematic diagram of the application of the high and low frequency vibrator coaxial installation platform of the present invention to the base station antenna;

Fig. 6 is a structural schematic diagram of the high and low frequency vibrator coaxial installation platform of the present invention;

Fig. 7 is an expanded view of the reflective spacer of the high-low frequency vibrator coaxial installation platform of the present invention;

Fig. 8 is a side view of the reflective spacer of the high-low frequency vibrator coaxial installation platform of the present invention.

【Detailed ways】

Please refer to Figures 5-8, the base station antenna of the present invention includes a high-frequency vibrator 411 and a low-frequency vibrator 412 coaxially arranged on the reflector 500, and a coaxial installation platform for the high-low frequency vibrator, and the coaxial installation platform for the high-low frequency vibrator is set on In the low-frequency vibrator 412, the high-frequency vibrator 411 is arranged on the coaxial installation platform of the high-low frequency vibrator.

The embodiment of the high-low frequency vibrator coaxial installation platform of the present invention includes a mounting base 420, and an isolation reflection sheet 430 arranged on the installation base. There are four extension parts 432 extending in four directions. The extension part 432 extends obliquely upward, and there is an included angle between the plane where the extension part 432 is located and the plane where the central part 431 is located.

The angle between the extension direction of the extension part 432 and the polarization direction of the vibrator is 45°. When the electromagnetic wave radiated by the low-frequency vibrator 412 is incident on the cross reflective surface, the phase centers of the main polarization and cross-polarization components are synchronized by the induced current flowing through the center of the cross, thus the low-frequency cross-polarization is improved and the gain is also obtained. promote.

The extension part 432 extends obliquely upward, and the included angle between the plane where the extension part 432 is located and the plane where the central part 431 is located ranges from 0° to 90°. In this embodiment, the central part 431 is a square, the side length L of the central part 431, the height H of the extending part 432 extending from the central part, and the extending part 432 is in a convex shape, including a connecting center The base portion 433 of the portion 431 and the protruding portion 434 extending from the outer edge of the base portion 433 enhance the low-frequency resonance on the one hand, and suppress the high-frequency resonance on the other hand, thereby avoiding negative effects on the high-frequency vibrator. The width L1 of the protruding portion 434 and the height H1 of the protruding portion 434 extending from the base portion 433 .

For the most common coaxial array application of 690-960MHz low-frequency oscillator 412 and 1710-2690MHz high-frequency oscillator 411, the parameters in the figure are as follows: L=60mm, H=18mm, L1=50mm, H1=5mm. The extension 432 of the cross-shaped isolation reflector 430 is bent upward at an angle of 30°. This angle is the result of optimization of the electromagnetic field simulation software, which not only enhances the reflection of high-frequency electromagnetic waves, but also reduces the scattering on the surface of the high-frequency vibrator. , without making the scattering cross-section too large to affect the low-frequency cross-polarization. Furthermore, after the wave beams radiated by the high-frequency vibrator are reflected by the extension part, the axial propagation distance tends to be consistent, thereby achieving greater gain.

The invention discloses a high-low frequency oscillator coaxial installation platform with low-frequency orthogonal mode conversion and high-frequency gain enhancement. The installation platform is not only a high-frequency reflector, but also has the functions of isolating low-frequency oscillators and improving high-frequency beam dispersion. It is a low-frequency polarization separator, which has the function of improving low-frequency cross-polarization discrimination and enhancing low-frequency gain.

The basic shape is a cross-shaped sheet bent upwards, the extensions point to the horizontal plane at 0° and 90° respectively, and the included angle with the polarization direction of the vibrator is 45°. When the electromagnetic wave radiated by the low-frequency vibrator is incident on the reflecting surface of the extension part, the phase centers of the main polarization and cross-polarization components are synchronized by the induced current flowing through the center of the cross, so that the low-frequency cross-polarization is improved and the gain is also improved. .

The present invention retains the basic shape of the cross, thereby still supporting polarization mode conversion, but cancels the slot and replaces it with an edge extension. The advantage of this is: on the one hand, the low-frequency resonance is enhanced, and on the other hand, the high-frequency resonance is suppressed Occurrence, thus avoiding the negative impact on the high frequency oscillator.

The invention solves the serious interactive interference that occurs when the high and low frequency vibrator of the base station antenna is coaxially installed, and is especially suitable for the coaxial installation of the 698-960MHz low-frequency four-lobe vibrator and the 1710-2690MHz high-frequency vibrator, and is useful for improving antenna gain and overcoming cross polarization It has considerable value; in addition, the invention has a simple structure, can be manufactured through basic sheet metal technology, has low cost, and is suitable for mass production.

The central portion of the isolation reflective sheet of the present invention can also be in other shapes, such as rectangle or polygon. The basic shape of the present invention is that an upwardly bent extension is provided on the outer periphery of the central portion. The design results obtained from any modification implemented on this basis shall be included in the scope of protection of this patent.

The above descriptions are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereto. Any equivalent transformation based on the technical solution of the present invention falls within the protection scope of the present invention.

Claims (10)

1. a kind of coaxial mounting platform of low-and high-frequency oscillator, it is characterised in that it includes mounting base, and is arranged in mounting base Isolate reflector plate, the isolation reflector plate is in cross, it includes central part, and is prolonged by central part periphery four direction The extension of stretching, the extension extend obliquely, and there are angle between plane where plane where it and central part.

2. the coaxial mounting platform of low-and high-frequency oscillator as claimed in claim 1, it is characterised in that the extension extending direction with Oscillator polarization direction angle is 45 °.

3. the coaxial mounting platform of low-and high-frequency oscillator as claimed in claim 1, it is characterised in that plane where the extension with Angle value range between plane where central part is at 0 °~90 °.

4. the coaxial mounting platform of low-and high-frequency oscillator as claimed in claim 3, it is characterised in that plane where the extension with Angle between plane where central part is 30 °.

5. the coaxial mounting platform of low-and high-frequency oscillator as claimed in claim 1, it is characterised in that the extension is in convex shape knot Structure, including it is directly connected to the base portion of the central part and the protuberance extended out by base portion outer ledge.

6. the coaxial mounting platform of low-and high-frequency oscillator as claimed in claim 3, it is characterised in that the central part is square.

7. the coaxial mounting platform of low-and high-frequency oscillator as claimed in claim 1, it is characterised in that the length of side L=of the central part 60mm±5mm。

8. the coaxial mounting platform of low-and high-frequency oscillator as claimed in claim 7, it is characterised in that the extension is prolonged by central part Stretch out the height H=18mm ± 5mm gone.

9. the coaxial mounting platform of low-and high-frequency oscillator as claimed in claim 8, it is characterised in that the width L1=of the protuberance 50mm ± 5mm, height H1=5mm ± 1mm that the protuberance is extended out by base portion.

A kind of 10. antenna for base station, it is characterised in that it includes the high frequency oscillator of coaxial setting and low-frequency vibrator, and such as right It is required that 1~9 coaxial mounting platform of any one of them low-and high-frequency oscillator, the coaxial mounting platform of low-and high-frequency oscillator are arranged on institute State in low-frequency vibrator, the high frequency oscillator is arranged on the coaxial mounting platform of low-and high-frequency oscillator.