阅读说明：本技术 基站天线 (Base station antenna ) 是由 张万春 张喆 陈曦 郭浩 于 2021-06-10 设计创作，主要内容包括：本发明实施例涉及无线通信技术领域,公开了一种基站天线,包括：天线地板、天线单元阵列、多个栅格板和多个去耦单元；天线单元阵列包括相互间隔地设置在天线地板上的多个天线单元；多个栅格板垂直设在天线地板上、并在每个天线单元的周围围成棱柱状结构；多个去耦单元与多个栅格板一一对应,每个去耦单元包括一对感应线,每个去耦单元的一对感应线互为镜像设置在对应的栅格板的两侧。本发明提供的基站天线,能够降低相邻两个天线单元间的耦合度,实现基站天线的小型化。(The embodiment of the invention relates to the technical field of wireless communication, and discloses a base station antenna, which comprises: the antenna comprises an antenna floor, an antenna unit array, a plurality of grid plates and a plurality of decoupling units; the antenna unit array comprises a plurality of antenna units which are arranged on the antenna floor at intervals; the grid plates are vertically arranged on the antenna floor, and a prismatic structure is formed around each antenna unit; the decoupling units are in one-to-one correspondence with the grid plates, each decoupling unit comprises a pair of induction lines, and the pair of induction lines of each decoupling unit are arranged on two sides of the corresponding grid plate in a mirror image mode. The base station antenna provided by the invention can reduce the coupling degree between two adjacent antenna units and realize the miniaturization of the base station antenna.)

1. A base station antenna, comprising:

an antenna floor;

an antenna element array including a plurality of antenna elements disposed on the antenna floor at intervals;

the grid plates are vertically arranged on the antenna floor and surround a prismatic structure around each antenna unit;

the decoupling units correspond to the grid plates one to one, each decoupling unit comprises a pair of induction lines, and the pair of induction lines of each decoupling unit are arranged on two sides of the corresponding grid plate in a mirror image mode.

2. The base station antenna of claim 1, wherein:

each grid plate is rectangular, the long edge of each grid plate is arranged in parallel to the antenna floor, each induction line on each grid plate comprises a first extension branch and two second extension branches, the first extension branch of each induction line is arranged in parallel to the long edge of the grid plate, and the two second extension branches of each induction line extend from the first extension branch and are bent and extended in the direction of deviating from each other at the tail end far away from the first extension branch so as to form a pi-shaped structure with the first extension branch.

3. The base station antenna according to claim 1 or 2, characterized in that:

the antenna units are arranged on the antenna floor in parallel along a first direction by taking N antenna units as one row, and two adjacent rows of the antenna units are arranged in a staggered manner;

wherein N is an integer greater than 1.

4. The base station antenna of claim 3, wherein:

the distance between the central axes of two adjacent rows of the antenna units is 0.35 lambda-0.4 lambda;

wherein λ is a wavelength at which the antenna unit transmits an electromagnetic wave in free space at a center frequency.

5. The base station antenna of claim 4, wherein:

the distance between the plane centers of two adjacent antenna units in the same column is 0.6 lambda-0.7 lambda.

6. The base station antenna of claim 1, wherein:

every antenna element includes two balun boards, an antenna substrate and two pairs of oscillator arms, every two of antenna element the balun board is established with the cross-shaped cross structure is perpendicular on the antenna floor, every antenna element the antenna substrate is kept flat two on the cross-shaped cross structure that the balun board formed, every one of them a pair of antenna element the oscillator arm is established along first polarization direction subsides on the antenna substrate, every another a pair of antenna element the oscillator arm is established along second polarization direction subsides on the antenna substrate, first polarization direction with second polarization direction mutually perpendicular.

7. The base station antenna of claim 6, wherein:

four grid plates are arranged around each antenna unit, two grid plates around each antenna unit are arranged in parallel to the first polarization direction, and the other two grid plates around each antenna unit are arranged in parallel to the second polarization direction.

8. The base station antenna according to claim 6 or 7, characterized in that:

every of every antenna element every the oscillator arm all sets up to square, and every of antenna element the middle part fretwork setting of oscillator arm.

9. The base station antenna of claim 1, wherein:

the plurality of grid plates surround each antenna unit to form a closed prismatic structure, and two grid plates connected with each other are arranged in an interpenetration mode.

10. The base station antenna of claim 9, wherein:

each grid plate is a PCB (printed circuit board) dielectric plate, and the pair of induction lines on each grid plate are printed on two opposite surfaces of the PCB dielectric plate.

Technical Field

The embodiment of the invention relates to the technical field of wireless communication, in particular to a base station antenna.

Background

With the rapid development of wireless communication technology, the amount of information transmitted and received between a communication base station and a mobile terminal has increased exponentially. The traditional single-Input single-Output communication mode has become more and more difficult to meet the requirement of people for high-speed transmission of large information amount, and the MIMO (Multiple-Input Multiple-Output) technology is proposed to solve the problem.

The MIMO technology is to use a plurality of transmitting antennas and receiving antennas at a transmitting end and a receiving end, respectively, so that signals are transmitted and received through the plurality of antennas of the transmitting end and the receiving end, thereby improving communication quality. Therefore, the space resources can be fully utilized, multiple sending and multiple receiving are realized through a plurality of antennas, and the system channel capacity can be improved in multiples under the condition that the frequency spectrum resources and the antenna transmitting power are not increased.

However, the MIMO communication system still has problems to be overcome, the MIMO communication system requires a transceiver to simultaneously receive and transmit signals in multiple links, and the biggest problem of the multi-antenna design is that coupling between adjacent antennas is difficult to avoid, and multiple antennas cannot independently transmit information due to mutual coupling influence between adjacent antennas. In a large-scale planar array antenna, the number of antenna units is large, the antenna size can be effectively reduced by reducing the array spacing of the antenna units under a certain working frequency condition, more antennas can be distributed in unit area, the weight is lighter, and the operation cost can be reduced. However, the reduction of the antenna array spacing can cause stronger energy mutual coupling between the antenna units, which further causes the antenna isolation to be poor and the directional diagram to be distorted, thereby causing the antenna performance index to be deteriorated and affecting the communication efficiency. Therefore, how to reduce the coupling degree between the antenna units to achieve the miniaturization of the base station antenna is an urgent problem to be solved when designing the MIMO antenna.

Disclosure of Invention

The embodiment of the invention mainly aims to provide a base station antenna, which can reduce the coupling degree between adjacent antenna units and realize the miniaturization of the base station antenna.

To achieve the above object, an embodiment of the present invention provides a base station antenna, including:

an antenna floor;

an antenna element array including a plurality of antenna elements disposed on the antenna floor at intervals;

the grid plates are vertically arranged on the antenna floor and surround a prismatic structure around each antenna unit;

the decoupling units correspond to the grid plates one to one, each decoupling unit comprises a pair of induction lines, and the pair of induction lines of each decoupling unit are arranged on two sides of the corresponding grid plate in a mirror image mode.

The invention provides a base station antenna, which comprises an antenna floor, an antenna unit array, a plurality of grid plates and a plurality of decoupling units, wherein each antenna unit of the antenna unit array is arranged on the antenna floor, the multi-input and multi-output of the base station antenna can be realized through the antenna unit array, the plurality of grid plates surround each antenna unit to form a prism structure, a pair of induction lines of the decoupling units are arranged on two sides of the corresponding grid plate in a mirror image manner, so that the decoupling grid structure is formed around each antenna unit, therefore, when the base station antenna works, space electromagnetic waves between two adjacent antenna units generate coupling energy, an indirect coupling field corresponding to a direct coupling field between two adjacent antenna units is formed by inducing induction currents with equal and opposite phases on the decoupling units, and the indirect coupling field is mutually offset with the direct coupling field between two adjacent antenna units, therefore, mutual coupling influence between two adjacent antenna units is weakened, and the isolation between the two adjacent antenna units is improved, so that the miniaturization of the base station antenna is realized.

Drawings

Fig. 1 is a schematic perspective view of a base station antenna according to an embodiment of the present invention;

FIG. 2 is a schematic top view of the base station antenna of FIG. 1;

FIG. 3 is a schematic front view of the base station antenna of FIG. 1;

FIG. 4 is a schematic view of the structure of FIG. 1 with sensing lines disposed on the grid plate;

fig. 5 is a schematic structural diagram of the base station antenna when the antenna unit array in fig. 1 is a 3 × 3 array;

FIG. 6 is a comparison graph of antenna isolation simulation of the base station antenna of FIG. 1 before and after loading of a decoupling grid structure;

fig. 7 is a simulated gain pattern of the base station antenna of fig. 1 without a decoupling grid structure;

fig. 8 is a simulated gain pattern for the base station antenna of fig. 1 when a decoupling grid structure is provided.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, it will be appreciated by those of ordinary skill in the art that in various embodiments of the invention, numerous technical details are set forth in order to provide a better understanding of the present invention. However, the claimed invention may be practiced without these specific details or with various changes and modifications based on the following embodiments. The following embodiments are divided for convenience of description, and should not constitute any limitation to the specific implementation manner of the present invention, and the embodiments may be mutually incorporated and referred to without contradiction.

The embodiment of the invention relates to a base station antenna, as shown in fig. 1 to 4, including an antenna floor 100, an antenna unit array 200, a plurality of grid plates 300, and a plurality of decoupling units 400, wherein the antenna unit array 200 includes a plurality of antenna units 210 disposed on the antenna floor 100 at intervals, the plurality of grid plates 300 are disposed on the antenna floor 100 vertically and surround each antenna unit 210 to form a prism-shaped structure, the plurality of decoupling units 400 correspond to the plurality of grid plates 300 one to one, each decoupling unit 400 includes a pair of induction lines 410, and the pair of induction lines 410 of each decoupling unit 400 are disposed on two sides of the corresponding grid plate 300 in a mirror image manner. The antenna element array 200 is used to realize multiple input and multiple output of the base station antenna, and the plurality of grid plates 300 are formed in a prism shape around each antenna element 210, so that a grid structure having decoupling elements 400 is formed on the antenna floor 100 to isolate mutual coupling influence between two adjacent antenna elements 210.

Compared with the prior art, the embodiment of the present invention provides a base station antenna with a decoupling grid structure, the decoupling grid structure includes a plurality of grid plates 300, a pair of induction lines 410 which are mirror images of each other are disposed on two sides of each grid plate 300, and such grid plates 300 enclose a prism-shaped structure around each antenna unit 210. Thus, when the base station antenna is in operation, the plurality of antenna units 210 of the antenna unit array 200 may be used to implement multiple inputs and multiple outputs of the antenna, and at the same time, the spatial electromagnetic waves between two adjacent antenna units 210 generate coupling electromagnetic energy, and induced currents with equal magnitude and opposite phases are induced on the decoupling unit 400 of the grid plate 300, so as to form an indirect coupling field corresponding to the direct coupling field between two adjacent antenna units 210, and the current of the indirect coupling field is equal in magnitude and opposite in phase to the current of the direct coupling field between two adjacent antenna units 210, so as to achieve the purpose of forming an indirect coupling field on the decoupling unit 400 of the grid plate 300, which cancels the direct coupling field between two adjacent antenna units 210, so as to weaken the mutual coupling effect between two adjacent antenna units 210, so as to achieve the purpose of suppressing the mutual coupling effect between two adjacent antenna units 210, the isolation between adjacent antenna units 210 is improved to achieve miniaturization of the base station antenna.

The sensing lines 410 may adopt a pi-type structure, specifically, as shown in fig. 4, each grid plate 300 is a rectangular plate, the long side of each grid plate 300 is arranged parallel to the antenna floor 100, each sensing line 410 on each grid plate 300 includes a first extending branch 411 and two second extending branches 412, the first extending branch 411 of each sensing line 410 is arranged parallel to the long side of the grid plate 300, and the two second extending branches 412 of each sensing line 410 extend from the first extending branch 411 and are bent and extended in a direction away from each other at the end far away from the first extending branch 411 to form a pi-type structure with the first extending branch 411. The sensing lines 410 of the pi-shaped structure are disposed on two sides of each grid plate 300, when the base station antenna operates, electromagnetic waves in the space around the antenna units 210 and the sensing lines 410 generate an electromagnetic induction action, where the decoupling unit 400 including a pair of the sensing lines 410 can be regarded as a resonant structure, two adjacent antenna units 210 can induce induction currents with equal magnitude and opposite phases on the decoupling unit 400, so as to form an indirect coupling field which is mutually offset with a direct coupling field between two adjacent antenna units 210, so as to improve the isolation between two adjacent antenna units 210, and the resonant frequency on the sensing lines 410 can be adjusted by changing the size of the pi-shaped structure.

It should be noted that the sensing lines 410 are used for generating electromagnetic induction on the grid plate 300, and such sensing lines 410 may be, but not limited to, the pi-shaped structure described above, and may also adopt an L-shaped structure, a T-shaped structure, a # -shaped structure, and the like, and the pi-shaped structure may be made lower in the height direction than structures of other shapes, which is beneficial to further realizing miniaturization of the base station antenna. After the base station antenna is added with the grid structure with the decoupling unit 400, the mutual coupling influence between the adjacent antenna units 210 in the antenna unit array 200 can be suppressed, so as to realize the miniaturization of the base station antenna, and a specific example is given here to embody the miniaturization of the base station antenna, for example, the horizontal spacing of the conventional antenna unit array 200 is 0.5 λ, and after the grid structure with the decoupling unit is loaded, the horizontal spacing of the antenna unit array 200 can be set to 0.35 λ, where λ is the wavelength of the electromagnetic wave transmitted by the center frequency of the antenna unit 210 in the free space.

In addition, the above-mentioned arrangement form of the antenna unit array 200 may be, but is not limited to, a staggered form in which a plurality of antenna units 210 are arranged in parallel on the antenna floor 100 in a first direction S in N as one column, and two adjacent columns of antenna units 210 are arranged in a staggered manner with respect to each other, where N is an integer greater than 1. In the parallel form, the plurality of antenna units 210 are arranged on the antenna floor 100 in parallel along the first direction S in N rows, and two adjacent rows of antenna units 210 are arranged opposite to each other, where N is also an integer greater than 1.

Here, as an alternative embodiment, as shown in fig. 5, the plurality of antenna units 210 may be arranged in parallel on the antenna floor 100 in the first direction S in 3 rows, such that the number of the antenna units 210 is 3 in total, and two adjacent rows of the antenna units 210 are arranged in a staggered manner, that is, as shown in fig. 5, the antenna unit 210 in the middle row is arranged opposite to the interval between two adjacent antenna units 210 in the next row, and this staggered arrangement can improve the isolation between the adjacent antenna units 210 compared with the parallel arrangement. Meanwhile, the distance between the central axes of two adjacent rows of antenna units 210 (in fig. 5, the horizontal distance or the horizontal distance between the antenna units 210) may be 0.35 λ -0.4 λ, where λ is the wavelength of the electromagnetic wave transmitted by the central frequency of the antenna unit 210 in the free space, so that the distance between the central axes of two adjacent rows of antenna units 210 can be reduced to achieve miniaturization of the base station antenna while ensuring the basic coverage performance of the base station antenna, and when the distance between the central axes of two adjacent rows of antenna units 210 exceeds 0.4 λ, it is not favorable to achieve miniaturization of the base station antenna, and when the distance between the central axes of two adjacent rows of antenna units 210 is less than 0.35 λ, the antenna performance loss is serious, or even it cannot be used. And the distance between the planar centers of two adjacent antenna elements 210 located in the same column (the longitudinal or vertical spacing between the antenna elements 210 in fig. 5) may be 0.6 λ -0.7 λ.

The antenna element array 200 is a 3 × 3 array, and in the 3 × 3 array, the horizontal spacing dimension and the vertical spacing dimension of the adjacent antenna elements 210 may be fixed values of the above values, and the above values still apply when the number of the antenna element arrays 200 is changed. In addition, the miniaturization of the base station antenna is mainly focused on reducing the horizontal spacing between adjacent antenna elements 210, and the vertical spacing between adjacent antenna elements 210 is not considered when designing the base station antenna for miniaturization, as in the conventional base station antenna.

Fig. 6 shows a comparison graph of the isolation simulation of the base station antenna with and without the isolation grid structure, wherein the horizontal axis of fig. 6 represents the operating frequency of the antenna unit 210 and the vertical axis represents the reflection coefficient of the base station antenna, and graphs of the simulation results are sequentially given in fig. 6 with and without the decoupling grid structure loaded. As can be seen from fig. 6, when the decoupling grid structure is applied to a MIMO antenna, the mutual coupling effect between adjacent antenna units 210 can be improved, when the decoupling grid structure is not added, the isolation curves of two ports (three antenna units 210 located in the longitudinal direction are combined into one port) are two smooth curves between-10 dB and 15dB (Decibel ), when the decoupling grid structure is loaded, the isolation curves of the two ports generate two high-rejection points at the corresponding center frequencies of the antenna units 210, at this time, the zero depth (referring to the vertical coordinate value of the deep concave point in the isolation simulation contrast diagram) of the isolation curve reaches-35 dB, the worst value of the isolation curve reaches-20 dB, and compared with the decoupling grid structure, the isolation of the base station antenna is improved by 5dB to 10 dB.

Fig. 7 and 8 respectively show simulated directional gain diagrams of the base station antenna with or without the isolation grid, where fig. 7 is the simulated directional gain diagram of the base station antenna without the decoupling grid structure loaded, and fig. 8 is the simulated directional gain diagram of the base station antenna with the decoupling grid structure loaded, and it can be seen that the simulated curve in fig. 8 is more uniform in gain distribution on the radiation plane compared with the simulated curve in fig. 7, and thus it can be seen that the isolation grid structure described above can improve the problem of pattern distortion caused by the mutual coupling effect between adjacent antenna units 210.

The antenna unit 210 may be a dual-polarized element antenna, where the dual-polarized element antenna includes two polarization directions, and each polarization direction has a pair of oscillator arm patches for radiation. Specifically, each antenna unit 210 includes two balun plates 211, an antenna substrate 212, and two pairs of dipole arms 213, the two balun plates 211 of each antenna unit 210 are vertically disposed on the antenna floor 100 in a cross structure, the antenna substrate 212 of each antenna unit 210 is flatly disposed on the cross structure formed by the two balun plates 211, one pair of dipole arms 213 of each antenna unit 210 is attached to the antenna substrate 212 along a first polarization direction a (shown in fig. 1), the other pair of dipole arms 213 of each antenna unit 210 is attached to the antenna substrate 212 along a second polarization direction B (shown in fig. 1), and the first polarization direction a and the second polarization direction B are two directions perpendicular to each other. The balun plate 211 is used to feed the oscillator arm 213 and performs balanced feeding and impedance conversion, and the balun plate 211 has a microstrip line, and the bottom of the microstrip line is connected by an SMA (SubMiniature conversion a) joint.

In order to better reduce mutual coupling between adjacent antenna units 210, the grid plates 300 may be disposed opposite to the polarization directions of the dipole arms 213 in the antenna units 210, specifically, four grid plates 300 are surrounded around each antenna unit 210, two grid plates 300 of the surrounding of each antenna unit 210 are disposed parallel to the first polarization direction a, and the other two grid plates 300 of each antenna unit 210 are disposed parallel to the second polarization direction B. In this way, in the grid plate 300 surrounding each antenna unit 210, two of the two polarization directions (the first polarization direction a) facing one pair of dipole arms 213 are arranged, and the other two polarization directions (the second polarization direction B) facing the other pair of dipole arms 213 are arranged, so that the isolation between the same polarization directions of adjacent antenna units 210 can be improved, and the mutual coupling effect between the adjacent antenna units 210 can be better reduced.

As a preferred embodiment, the current path on the surface of the antenna may be increased by a meander principle to achieve miniaturization of the antenna, and specifically, each of the dipole arms 213 of each of the antenna units 210 is configured to be square, and a middle portion of the dipole arm 213 of each of the antenna units 210 is hollowed. Thus, each of the dipole arms 213 is shaped like a ring, and the current will flow along the ring patch of each of the dipole arms 213, thereby increasing the current path on the antenna surface.

In addition, in order to form a stable structure of the plurality of grid plates 300 on the antenna floor 100, the plurality of grid plates 300 may be enclosed into a closed prism-shaped structure around the antenna unit 210, and two grid plates 300 connected to each other may be inserted into each other, so that the plurality of grid plates 300 are connected to each other to form an integral grid structure, and the connection strength between the grid plates 300 is improved, so that the entire grid structure is more stable and is less likely to deform. Meanwhile, since the transverse and longitudinal pitches between the antenna units 210 are not equal, it is also more convenient to arrange the grid plate 300 around each antenna unit 210 by the directions of interdigitation. It should be noted that the grid plate 300 may also be enclosed around each antenna unit 210 in a mutually separated manner, that is, a plurality of grid plates 300 enclose a non-closed prism-like structure around each antenna unit 210, and the purpose of reducing the mutual coupling influence between adjacent antenna units 210 can also be achieved.

As an alternative embodiment, each grid plate 300 may be a PCB (Printed Circuit Board) dielectric plate, and the pair of sensing lines 410 on each grid plate 300 are Printed on opposite surfaces of the PCB dielectric plate.

It will be understood by those of ordinary skill in the art that the foregoing embodiments are specific examples for carrying out the invention, and that various changes in form and details may be made therein without departing from the spirit and scope of the invention in practice.