CN111384595B

CN111384595B - MIMO antenna and base station

Info

Publication number: CN111384595B
Application number: CN201811642792.7A
Authority: CN
Inventors: 邸允会; 肖伟宏; 谢国庆; 何鑫
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2018-12-29
Filing date: 2018-12-29
Publication date: 2021-07-16
Anticipated expiration: 2038-12-29
Also published as: CN111384595A; WO2020135537A1

Abstract

The embodiment of the application discloses a multi-input multi-output antenna, which comprises a reflecting plate, a first antenna unit, a second antenna unit and a first decoupling connecting line. The first antenna unit comprises a first support erected on the reflecting plate and a first radiation arm positioned on the first support. The second antenna unit comprises a second support erected on the reflecting plate and a second radiation arm positioned on the second support. The polarization direction of the first radiating arm is the same as the polarization direction of the second radiating arm. The first decoupling connecting line comprises a first coupling section, a first transmission section, a first connecting section, a second transmission section and a second coupling section which are connected in sequence. The first connecting section is located on the reflecting plate, the first coupling section is located on the first support and coupled with the first radiating arm, and the second coupling section is located on the second support and coupled with the second radiating arm. The multiple-input multiple-output antenna has high isolation. The embodiment of the application also discloses a base station.

Description

MIMO antenna and base station

Technical Field

The present application relates to the field of mobile communications technologies, and in particular, to a mimo antenna and a base station using the mimo antenna.

Background

A large-scale multiple-input multiple-output (MIMO) antenna uses a plurality of transmitting antennas and a plurality of receiving antennas at a transmitting end and a receiving end thereof, 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. The multi-antenna multi-transmission multi-reception mobile communication system can fully utilize space resources, realizes multi-transmission and multi-reception through a plurality of antennas, can improve the system channel capacity by times under the condition of not increasing frequency spectrum resources and antenna transmitting power, shows obvious advantages, and is regarded as a core technology of 5G mobile communication.

The existing MIMO antenna has a large number of units, which results in a large overall size of the MIMO antenna. In order to reduce the size of the mimo antenna, the spacing between the same-frequency units is smaller and smaller, which results in stronger and stronger coupling between the same-frequency units and deterioration of unit electrical indexes.

Disclosure of Invention

The embodiment of the application provides a high-isolation MIMO antenna and a base station applying the same.

In a first aspect, the present application provides a mimo antenna. The MIMO antenna comprises a reflecting plate, a first antenna unit, a second antenna unit and a first decoupling connecting line.

The first antenna unit comprises a first support erected on the reflecting plate and a first radiation arm positioned on the first support. The second antenna unit comprises a second support erected on the reflecting plate and a second radiation arm positioned on the second support. The first support and the second support are adjacent and arranged at intervals. The polarization direction of the first radiation arm is the same as the polarization direction of the second radiation arm.

The first decoupling connecting line comprises a first coupling section, a first transmission section, a first connecting section, a second transmission section and a second coupling section. The first connection section is located on the reflection plate. The first coupling segment is located on the first support and coupled with the first radiating arm. The first transmission section is located on the first bracket and connected between the first coupling section and one end of the first connection section. The second coupling section is located on the second support and coupled with the second radiating arm. The second transmission section is located on the second support and connected between the second coupling section and the other end of the first connection section.

In this embodiment, the first coupling segment of the first decoupling connection is capable of coupling a part of the current from the first radiating arm, and the part of the current is transmitted to the second coupling segment through the first transmission segment, the first connection segment and the second transmission segment in sequence and is coupled to the second radiating arm through the second coupling segment. That is, the first decoupling connecting line forms a current loop between the first radiating arm and the second radiating arm, so that currents coupled with a space between the first radiating arm and the second radiating arm are mutually superposed and offset, the coupling between the first radiating arm and the second radiating arm is weakened, the isolation between the first radiating arm and the second radiating arm is improved, the isolation between the adjacent first antenna unit and the second antenna unit is higher, and the mimo antenna has high isolation.

In this embodiment, since the isolation between the first antenna element and the second antenna element is high, the distance between the first antenna element and the second antenna element may be small, for example, the center-to-center distance between the first antenna element and the second antenna element may be smaller than one-half wavelength. Therefore, the MIMO antenna can realize compact arrangement and keep high isolation.

In this embodiment, the first radiation arm and the reflection plate are located on different planes, and the second radiation arm and the reflection plate are located on different planes. Because the first coupling section is arranged on the first support along with the first radiation arm, the first transmission section is also arranged on the first support to connect the first coupling section and the first connection section positioned on the reflection plate, the second coupling section is arranged on the second support along with the second radiation arm, and the second transmission section is also arranged on the second support to connect the second coupling section and the first connection end positioned on the reflection plate, the first decoupling connection line can establish a three-dimensional transmission path by means of the first support, the reflection plate and the second support, thereby smoothly transmitting current in a three-dimensional space and solving the mutual coupling interference problem of non-planar units.

The first radiating arm and the second radiating arm may be low-frequency oscillators or high-frequency oscillators. The radiation frequency bands of the first radiation arm and the second radiation arm are not strictly limited in the embodiments of the present application.

In an alternative embodiment, the first decoupling connection further comprises a grounding segment. The grounding section is located on the reflecting plate. One end of the grounding section is connected with the first connecting section. The other end of the grounding section is grounded.

In this embodiment, the ground segment can be used to adjust the signal transmission phase to increase the bandwidth of the decoupling.

In an alternative embodiment, the first decoupling link further comprises an open segment. The open section is located on the reflection plate. One end of the open section is connected with the first connecting section. The other end of the open section is arranged in a suspended manner.

In this embodiment, the open segment can be used to adjust the signal transmission phase to increase the bandwidth of the decoupling.

In the embodiment of the present application, the grounding segment and the opening segment can be used alone or in combination. The number of the ground segments may be one or more. When the grounding section is multiple, the grounding section is connected to different positions of the first connecting section. The number of the open sections may be one or more. When the number of the open sections is multiple, the open sections are connected to different positions of the first connecting section.

In an alternative embodiment, the first coupling section and the first radiating arm are located on opposite sides of the first support. In this case, the first coupling segment and the first radiating arm are stacked on both sides of the first support, and coupling therebetween can be formed in the thickness direction of the first radiating arm.

Or, the first coupling section and the first radiating arm are located on the same side of the first support, and the first coupling section and the first radiating arm are arranged at an interval. At this time, the first coupling section and the first radiation arm can form coupling in a planar direction of the first radiation arm. The first coupling section may be located on a side of the first radiating arm close to the reflector plate, or may be located on a side of the first radiating arm far from the reflector plate.

In an alternative embodiment, the reflective plate is a conductive plate. The conductive plate is grounded. An insulating layer is arranged between the first connecting section and the reflecting plate. The reflecting plate can be made by adopting processes of metal plates, die casting, section bars and the like. The reflecting plate can be a metal plate such as an aluminum plate, a copper plate and the like.

In an alternative embodiment, the reflective plate comprises an insulating substrate and a conductive sheet located on the bottom side of the insulating substrate. The reflection plate may be a circuit board structure. The conducting strip is grounded. The conductive sheet may be a copper foil. The first support and the second support are fixed on the insulating base material and are positioned on the top side of the insulating base material. The first connection segment is located on the top side of the insulating substrate.

Wherein the first connection segment may be a waveguide transmission line. The first connection section is fixed to the reflection plate by a mounting method. Alternatively, the first connection segment may be a microstrip transmission line. The first connection section is integrally formed on the reflection plate in a manufacturing process of the reflection plate.

In an alternative embodiment, the first antenna element further comprises a first connecting arm. The first connecting arm is located on the first support, and one end of the first connecting arm is connected with the first radiation arm. The other end of the first connecting arm is electrically connected to the ground of the reflection plate.

In this embodiment, the ground of the reflective plate refers to a portion of the reflective plate that is grounded. For example, when the whole of the reflection plate is a conductive plate and is grounded, the ground of the reflection plate is the reflection plate. When the reflecting plate comprises the insulating base material and the grounded conducting strip, the ground of the reflecting plate is the conducting strip. In other embodiments, the first radiation arm may also be suspended from the ground of the reflection plate.

In an alternative embodiment, the first transmission segment may be a metal suspension wire. That is, the first transmission segment may be set in the air, and the signal transmitted in the first transmission segment does not have a reference ground. Wherein, the second transmission section can also be a metal suspension wire.

In an alternative embodiment, the first antenna element further comprises a third radiating arm. The third radiation arm is positioned on the first support and is arranged at an interval with the first radiation arm. The polarization direction of the third radiation arm is the same as that of the first radiation arm, so that a dipole unit is formed together with the first radiation arm.

The mimo antenna further includes a third antenna element and a second decoupling connection.

The third antenna unit comprises a third support erected on the reflecting plate and a fourth radiation arm positioned on the third support. The third support and the first support are adjacent and arranged at intervals. The third support is positioned on one side of the first support, which is far away from the second support. The third holder, the first holder, and the second holder are arranged in this order substantially in the same direction. The polarization direction of the fourth radiating arm is the same as the polarization direction of the third radiating arm.

The second decoupling connecting line comprises a third coupling section, a third transmission section, a second connecting section, a fourth transmission section and a fourth coupling section. The second connecting section is located on the reflection plate. The third coupling section is located on the first support and coupled with the third radiating arm. The third transmission section is located on the first support and connected between the third coupling section and one end of the second connection section. The fourth coupling section is located on the third support and coupled with the fourth radiating arm. The fourth transmission section is located on the third support and connected between the fourth coupling section and the other end of the second connection section.

In this embodiment, the first radiating arm and the third radiating arm of the first antenna element together form a dipole element, and both radiating arms of the dipole element are decoupled from the radiating arms of the adjacent antenna elements through decoupling connection lines, so as to ensure that the dipole element has higher isolation and better antenna performance.

In an alternative embodiment, the first support comprises a first support plate and a second support plate perpendicular to the first support plate. The first radiating arm is positioned on the first support plate. The first antenna element further comprises a fifth radiating arm located on the second support plate. The polarization direction of the fifth radiation arm is perpendicular to the polarization direction of the first radiation arm, so that the fifth radiation arm and the first radiation arm jointly form a dual-polarized oscillator unit.

The mimo antenna further includes a fourth antenna element and a third decoupling connection.

The fourth antenna unit comprises a fourth support erected on the reflecting plate and a sixth radiation arm positioned on the fourth support. The fourth support and the first support are adjacent and arranged at intervals. The polarization direction of the sixth radiation arm is the same as the polarization direction of the fifth radiation arm.

The third decoupling connecting line comprises a fifth coupling section, a fifth transmission section, a third connecting section, a sixth transmission section and a sixth coupling section. The third connecting section is located on the reflection plate. The fifth coupling section is located on the first support and coupled with the fifth radiating arm. The fifth transmission section is located on the first support and connected between the fifth coupling section and one end of the third connection section. The sixth coupling section is located on the fourth support and coupled with the sixth radiating arm. The sixth transmission section is located on the fourth support and connected between the sixth coupling section and the other end of the third connection section.

In this embodiment, the first antenna unit includes the first supporting plate and the second supporting plate that are perpendicular to each other, and the polarization direction of the first radiating arm on the first supporting plate is perpendicular to the polarization direction of the fifth radiating arm on the second supporting plate to form a dual-polarized element unit, that is, the first antenna unit includes two antennas, and the isolation of the two antennas whose polarization directions are perpendicular to each other is high, so that the mimo antenna can arrange more antennas without sacrificing the volume, thereby having a larger channel capacity.

In this embodiment, since the fifth radiating arm is decoupled from the adjacent sixth radiating arm by the third decoupling connecting line, the coupling between the fifth radiating arm and the sixth radiating arm is weak, and the isolation between the fifth radiating arm and the sixth radiating arm is high, so that the isolation between the adjacent first antenna element and the adjacent fourth antenna element is high, and the mimo antenna has high isolation.

In a second aspect, an embodiment of the present application further provides a base station (base station), including any of the multiple-input multiple-output antennas described above. Because the MIMO antenna has high isolation and better performance, the base station can realize high-speed and high-quality signal transmission through the MIMO antenna.

Drawings

Fig. 1 is a schematic structural diagram of a mimo antenna according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of the mimo antenna shown in fig. 1 at another angle;

fig. 3 is an equivalent physical model of a partial structure of the mimo antenna shown in fig. 1;

fig. 4 is a partial structural view of the reflection plate shown in fig. 1.

Detailed Description

The following description will be made with reference to the drawings in the embodiments of the present application.

Referring to fig. 1 and fig. 2 together, fig. 1 is a schematic structural diagram of a mimo antenna 100 according to an embodiment of the present application; fig. 2 is a schematic structural diagram of the mimo antenna 100 shown in fig. 1 at another angle. In the embodiment of the present application, a multiple-input multiple-output (MIMO) antenna 100 may be applied to a base station as a base station antenna (base station antenna).

The mimo antenna 100 includes a reflection plate 10 and a plurality of antenna elements. A plurality of antenna units are mounted on the reflection plate 10 and spaced apart from each other. The plurality of antenna units may be arranged in a matrix. When the plurality of antenna elements of the conventional mimo antenna 100 are compactly arranged, adjacent antenna elements are easily coupled to cause radiation phase disorder, which is represented as a wave pit of a horizontal plane pattern, and a fluctuation of a downward inclination angle of a vertical plane pattern and a target angle deviation is large, and a level difference of a same polarization isolation metric is large.

In the present application, each antenna unit includes a bracket erected on the reflection plate 10 and a radiation arm located on the bracket. The plurality of multiple-output antennas further comprises a plurality of decoupling (decoupling) wires. Two adjacent antenna units have the same polarization direction, and a decoupling connecting line can be arranged between two adjacent radiation arms. The two ends of the decoupling connecting wire are respectively coupled with the two radiating arms to form a current loop between the two radiating arms, and the current loop and space coupling currents between the two radiating arms are mutually superposed and offset, so that the coupling strength between the two radiating arms is effectively reduced, and the isolation between the two antenna units is improved.

In the embodiments of the present application, an example of "an antenna unit includes a dual-polarized oscillator, and the oscillator is in the form of a dipole" is described. In other embodiments, the antenna elements may also include single polarized elements. In other embodiments, the element form of the antenna unit may be a monopole.

Referring to fig. 1 and fig. 3 together, fig. 3 is an equivalent physical model of a partial structure of the mimo antenna 100 shown in fig. 1.

The plurality of antenna elements includes a first antenna element 21. The first antenna element 21 includes a first support 211 erected on the reflection plate 10 and a plurality of radiation arms located on the first support 211.

The first bracket 211 includes a first support plate 2111 and a second support plate 2112 perpendicular to the first support plate 2111. The first support plate 2111 and the second support plate 2112 are both vertically mounted on the reflection plate 10. The first support plate 2111 and the second support plate 2112 are arranged to intersect each other, and have a substantially cross shape. The first support plate 2111 and the second support plate 2112 may be formed as an integral structure by assembling, or may be formed integrally.

The plurality of radiating arms of the first antenna element 21 includes a first radiating arm 212, a third radiating arm 213, a fifth radiating arm 214, and a seventh radiating arm 215. The first and third radiating

arms

212 and 213 are located on the first support plate 2111 and are spaced apart from each other. The polarization direction of the third radiation arm 213 is the same as the polarization direction of the first radiation arm 212 to form a dipole unit together with the first radiation arm 212. The polarization direction of the fifth radiation arm 214 is perpendicular to the polarization direction of the first radiation arm 212 to form a dual-polarized element unit together with the first radiation arm 212. The fifth radiation arm 214 and the seventh radiation arm 215 are located on the second support plate 2112, and are disposed spaced apart from each other. The polarization direction of the seventh radiation arm 215 is the same as that of the fifth radiation arm 214 to form a dipole unit together with the fifth radiation arm 214. The two groups of dipole elements of the first antenna element 21 together form a dual-polarized element.

In this embodiment, the first antenna unit 21 includes a first support plate 2111 and a second support plate 2112 that are perpendicular to each other, and the polarization directions of the first radiation arm 212 on the first support plate 2111 and the fifth radiation arm 214 on the second support plate 2112 are perpendicular to each other, so as to form a dual-polarized element unit, that is, the first antenna unit 21 includes two antennas, and the isolation of the two antennas whose polarization directions are perpendicular to each other is high, so that the mimo antenna 100 can arrange more antennas without sacrificing the volume, thereby having a larger channel capacity.

The plurality of antenna elements further includes a second antenna element 22. The second antenna unit 22 includes a second support 221 erected on the reflection plate 10 and a plurality of radiation arms located on the second support 221. The second antenna element 22 has the same structural design as the first antenna element 21. The first bracket 211 and the second bracket 221 are adjacent to each other and spaced apart from each other. The plurality of radiating arms of the second antenna element 22 includes a second radiating arm 222. The polarization direction of the first radiating arm 212 is the same as the polarization direction of the second radiating arm 222. The second bracket 221 includes a support plate parallel to the first support plate 2111 of the first bracket 211, and the second radiating arm 222 is located at an end of the support plate near the first support plate 2111. The first radiating arm 212 and the second radiating arm 222 are substantially parallel.

The plurality of decoupling wires includes a first decoupling wire 31. The first decoupling connection 31 includes a first coupling segment 311, a first transmission segment 312, a first connection segment 313, a second transmission segment 314, and a second coupling segment 315. The first connection section 313 is located on the reflection plate 10. The first connection section 313 is arranged substantially horizontally. The first coupling segment 311 is located on the first support 211 and coupled with the first radiation arm 212. The first transmission section 312 is located on the first bracket 211 and connected between the first coupling section 311 and one end of the first connection section 313. The first transmission section 312 is arranged substantially vertically. The second coupling section 315 is located on the second support 221 and coupled with the second radiating arm 222. The second transmission section 314 is located on the second bracket 221 and connected between the second coupling section 315 and the other end of the first connection section 313. The second transport section 314 is arranged substantially vertically. The first coupling section 311, the first transmission section 312, the first connection section 313, the second transmission section 314, and the second coupling section 315 are connected in sequence.

In the present embodiment, the first coupling segment 311 of the first decoupling connecting line 31 can couple a part of the current from the first radiating arm 212, and the part of the current is transmitted to the second coupling segment 315 through the first transmission segment 312, the first connection segment 313 and the second transmission segment 314 in sequence, and is coupled to the second radiating arm 222 through the second coupling segment 315. That is, the first decoupling connecting line 31 forms a current loop between the first radiation arm 212 and the second radiation arm 222, so that currents coupled with the space between the first radiation arm 212 and the second radiation arm 222 are mutually superposed and offset, the coupling between the first radiation arm 212 and the second radiation arm 222 is weakened, the isolation between the first radiation arm 212 and the second radiation arm 222 is improved, the isolation between the adjacent first antenna unit 21 and the adjacent second antenna unit 22 is higher, the mimo antenna 100 has high isolation, the distortion problems of S parameters (namely scattering parameters) and a directional diagram caused by high-frequency coupling are improved, and the antenna index is improved. Since the mimo antenna 100 has high isolation and good performance, a base station using the mimo antenna 100 can transmit signals at high speed and high quality through the mimo antenna 100.

In this embodiment, since the isolation between the first antenna element 21 and the second antenna element 22 is high, the distance between the first antenna element 21 and the second antenna element 22 may be small, for example, the center-to-center distance between the two may be smaller than one-half wavelength. Therefore, the mimo antenna 100 can realize a compact arrangement while maintaining a high isolation.

In the present embodiment, the first radiation arm 212 and the reflection plate 10 are located on different planes, and the second radiation arm 222 and the reflection plate 10 are located on different planes. Since the first coupling section 311 is disposed on the first support 211 along with the first radiation arm 212, the first transmission section 312 is also disposed on the first support 211 to connect the first coupling section 311 and the first connection section 313 located on the reflection plate 10, the second coupling section 315 is disposed on the second support 221 along with the second radiation arm 222, and the second transmission section 314 is also disposed on the second support 221 to connect the second coupling section 315 and the first connection end located on the reflection plate 10, the first decoupling connection line 31 can be constructed with a three-dimensional transmission path by means of the first support 211, the reflection plate 10 and the second support 221, so as to smoothly transmit current in a three-dimensional space, thereby solving the mutual coupling interference problem of non-planar units.

The radiating arm of the antenna unit in the application can be a low-frequency oscillator or a high-frequency oscillator. The radiation frequency band of the radiation arm of the antenna unit is not strictly limited in the embodiments of the present application. For example, the first and second radiating

arms

212 and 222 may be low-frequency oscillators or high-frequency oscillators.

In an alternative embodiment, the first decoupling connection further comprises a grounding segment 316. The ground section 316 is located on the reflection plate 10. The ground section 316 has one end connected to the first connection section 313. The other end of the ground segment 316 is grounded. In this embodiment, the ground segment 316 can be used to adjust the signal transmission phase to increase the bandwidth of the decoupling.

In an alternative embodiment, the first decoupled connection further comprises an open segment 317. The open section 317 is located on the reflection plate 10. One end of the open section 317 is connected to the first connection section 313. The other end of the open section 317 is suspended. In this embodiment, the open segment 317 can be used to adjust the signal transmission phase to increase the bandwidth of the decoupling.

In the present embodiment, the ground segment 316 and the open segment 317 can be used alone or in combination. The number of ground segments 316 may be one or more. When the grounding segment 316 is plural, the grounding segments 316 are connected to different positions of the first connecting segment 313. The number of open sections 317 may be one or more. When there are a plurality of open sections 317, the open sections 317 are connected to different positions of the first connection section 313.

In an alternative embodiment, as shown in fig. 1, the first coupling section 311 and the first radiating arm 212 are located on the same side of the first support plate 2111 of the first bracket 211, and the first coupling section 311 and the first radiating arm 212 are spaced apart from each other. At this time, the first coupling section 311 and the first radiation arm 212 can form coupling in the planar direction of the first radiation arm 212. Wherein, the first coupling segment 311 may be located at a side of the first radiation arm 212 close to the reflection plate 10. In other embodiments, the first coupling segment 311 may also be located on a side of the first radiation arm 212 away from the reflection plate 10.

In other embodiments, the first coupling segment 311 and the first radiating arm 212 are located on opposite sides of the first support plate 2111 of the first bracket 211. At this time, the first coupling segment 311 and the first radiation arm 212 are stacked on both sides of the first support 211, and coupling therebetween can be formed in the thickness direction of the first radiation arm 212.

In an alternative embodiment, the first transmission segment 312 may be a metal suspension wire. That is, the first transmission segment 312 may be set in a floating manner, and the signal transmitted in the first transmission segment 312 has no reference ground. The second transmission section 314 may also be a metal suspension wire.

Referring to fig. 1 and 4, fig. 4 is a schematic view of a portion of the reflective plate 10 shown in fig. 1.

In an alternative embodiment, the reflective plate 10 includes an insulating substrate 101 and a conductive sheet 102 disposed on the bottom side of the insulating substrate 101. The reflection plate 10 may be a circuit board structure. The conductive sheet 102 is grounded. The conductive sheet 102 may be a copper foil. The first bracket 211 and the second bracket 221 are fixed to the insulating substrate 101 and located on the top side of the insulating substrate 101. The first connection section 313 is located on the top side of the insulating substrate 101. At this time, the first connection segment 313 may be integrated in the manufacturing process of the reflection plate 10 to simplify the manufacturing process and the assembly process of the mimo antenna 100, and reduce the cost of the mimo antenna 100.

In another alternative embodiment, the reflective plate 10 is a conductive plate. The conductive plate is grounded. An insulating layer is disposed between the first connection section 313 and the reflection plate 10. The reflective plate 10 can be made of metal plate, die casting, or section bar. The reflection plate 10 may be a metal plate such as an aluminum plate or a copper plate.

In an alternative embodiment, the first connection section 313 may be a waveguide transmission line. The first connection section 313 is fixed to the reflection plate 10 by a mounting manner. Alternatively, the first connection segment 313 may be a microstrip transmission line (as shown in fig. 4). The first connection section 313 is integrally formed on the reflection plate 10 in the manufacturing process of the reflection plate 10.

In an alternative embodiment, as shown in fig. 1 and 3, the first antenna element 21 further comprises a first connecting arm 216. The first connecting arm 216 is located on the first bracket 211 and has one end connected to the first radiating arm 212. The first connection arm 216 is located on the first support plate 2111. The other end of the first connection arm 216 is electrically connected to the ground of the reflection plate 10.

In the present embodiment, the ground of the reflection plate 10 refers to a portion of the reflection plate 10 that is grounded. For example, when the entire reflection plate 10 is a conductive plate and is grounded, the ground of the reflection plate 10 is the reflection plate 10. Alternatively, as shown in fig. 4, when the reflective plate 10 includes the insulating base 101 and the conductive sheet 102 connected to the ground, the ground of the reflective plate 10 is the conductive sheet 102. In other embodiments, the first radiation arm 212 may also be suspended from the ground of the reflection plate 10.

Referring to fig. 1 and 2 together, in an alternative embodiment, the plurality of antenna units further includes a third antenna unit 23. The third antenna unit 23 includes a third support 231 standing on the reflection plate 10 and a plurality of radiation arms located on the third support 231. The third antenna element 23 has the same structural design as the first antenna element 21. The third brackets 231 are disposed adjacent to and spaced apart from the first brackets 211. The third support 231 is located on a side of the first support 211 remote from the second support 221. The third holder 231, the first holder 211, and the second holder 221 are arranged in this order in substantially the same direction. The plurality of radiating arms of the third antenna element 23 includes a fourth radiating arm 232. The polarization direction of the fourth radiation arm 232 is the same as the polarization direction of the third radiation arm 213. The third bracket 231 includes a support plate parallel to the first support plate 2111 of the first bracket 211, and the fourth radiation arm 232 is located at an end of the support plate near the first support plate 2111. The fourth radiating arm 232 is substantially parallel to the third radiating arm 213.

The plurality of decoupling connections also includes a second decoupling connection 32. The second decoupling connecting line 32 has the same structural design as the first decoupling connecting line 31. The second decoupling connection 32 includes a third coupling segment 321, a third transmission segment 322, a second connection segment 323, a fourth transmission segment 324, and a fourth coupling segment 325. The second connection section 323 is located on the reflection plate 10. The second connecting section 323 is arranged substantially horizontally. The third coupling segment 321 is located on the first support 211 and is coupled with the third radiating arm 213. The third transmission section 322 is located on the first support 211 and is connected between the third coupling section 321 and one end of the second connection section 323. The third transfer section 322 is arranged substantially vertically. The fourth coupling section 325 is located on the third support 231 and is coupled with the fourth radiation arm 232. The fourth transmission section 324 is located on the third support 231 and connected between the fourth coupling section 325 and the other end of the second connection section 323. The fourth transfer segment 324 is arranged substantially vertically. The third coupling segment 321, the third transmission segment 322, the second connection segment 323, the fourth transmission segment 324, and the fourth coupling segment 325 are connected in sequence.

In this embodiment, the first radiation arm 212 and the third radiation arm 213 of the first antenna element 21 together form a dipole element, and both radiation arms of the dipole element are decoupled from the radiation arms of the adjacent antenna elements through a decoupling connection line, so as to ensure that the dipole element has higher isolation and better antenna performance.

In an alternative embodiment, the plurality of antenna elements further comprises a fourth antenna element 24. The fourth antenna element 24 includes a fourth support 241 erected on the reflection plate 10 and a plurality of radiation arms located on the fourth support 241. The fourth antenna element 24 has the same structural design as the first antenna element 21. The fourth brackets 241 are adjacent to the first brackets 211 and spaced apart from each other. The plurality of radiating arms of the fourth antenna element 24 includes a sixth radiating arm 242. The polarization direction of the sixth radiation arm 242 is the same as the polarization direction of the fifth radiation arm 214. The fourth support 241 includes a support plate parallel to the second support plate 2112 of the first support 211, and the sixth radiation arm 242 is positioned at an end of the support plate near the second support plate 2112. The sixth radiating arm 242 is substantially parallel to the fifth radiating arm 214.

The plurality of decoupling links further includes a third decoupling link 33. The third decoupling connecting line 33 has the same structural design as the first decoupling connecting line 31. The third decoupling connection line 33 includes a fifth coupling segment 331, a fifth transmission segment 332, a third connection segment 333, a sixth transmission segment 334 and a sixth coupling segment 335. The third connection segment 333 is located on the reflection plate 10. The fifth coupling section 331 is located on the first support 211 and is coupled with the fifth radiation arm 214. The fifth transmission section 332 is located on the first support 211 and is connected between the fifth coupling section 331 and one end of the third connection section 333. The sixth coupling segment 335 is located on the fourth support 241 and is coupled with the sixth radiating arm 242. The sixth transmission segment 334 is located on the fourth support 241 and connected between the sixth coupling segment 335 and the other end of the third connection segment 333. The fifth coupling section 331, the fifth transmission section 332, the third connection section 333, the sixth transmission section 334, and the sixth coupling section 335 are connected in sequence.

In this embodiment, since the fifth radiation arm 214 is decoupled from the adjacent sixth radiation arm 242 through the third decoupling connection line 33, the coupling between the fifth radiation arm 214 and the sixth radiation arm 242 is weaker, and the isolation between the fifth radiation arm 214 and the sixth radiation arm 242 is higher, so that the isolation between the adjacent first antenna element 21 and the fourth antenna element 24 is higher, that is, the isolation between each of the two dual-polarized antennas of the first antenna element 21 and the adjacent antenna element is high, and the isolation of the mimo antenna 100 is higher.

Referring to fig. 1 and 2, the first antenna unit 21 further includes a third connecting arm 217. The third connecting arm 217 is located on the first support plate 2111. The third connecting arm 217 has one end connected to the third radiating arm 213 and the other end electrically connected to the ground of the reflection plate 10. The first antenna element 21 also includes a first feed line 218. The first radiation arm 212, the first connection arm 216, the third radiation arm 213, and the third connection arm 217 are located on one side of the first support plate 2111, and the first power feed line 218 is located on the other side of the first support plate 2111. The first feed line 218 is used to feed energy to the first and

third radiation arms

212 and 213. The first feeder line 218 is not in contact with the first and

third radiation arms

212 and 213, and the first and

third radiation arms

212 and 213 complete a balance-unbalance conversion by feeding of the first feeder line 218.

Among them, the first connection arm 216 and the third connection arm 217 may serve as a reference ground of the first power feeding line 218.

Wherein one end of the first feeding line 218 extends to the reflection plate 10 to be connected with the radio frequency front end through a feeding port 219 provided on the reflection plate 10. The other end of the first feed line 218 is suspended. The first power feeding line 218 is substantially L-shaped as a whole, and one end of the first power feeding line 218 remote from the reflection plate 10 has an inverted hook portion.

In this embodiment, the first support plate 2111 may be a Printed Circuit Board (PCB). The first radiation arm 212, the first connection arm 216, the third radiation arm 213, the third connection arm 217, the first power feeding line 218, a portion of the first decoupling connecting line 31, and a portion of the second decoupling connecting line 32 may be formed on the first support plate 2111 through a circuit board manufacturing process. At this time, part of the decoupling wires between the antenna units can be integrated in the manufacturing process of the antenna units, and the integration process is simple, so that the manufacturing process and the assembly process of the mimo antenna 100 are simplified, and the cost of the mimo antenna 100 is reduced.

Wherein the first antenna element 21 further comprises a second feed line 2110. The second feeder line 2110 is located on the second support plate 2112. The fifth radiation arm 214 and the seventh radiation arm 215 are located at one side of the second support plate 2112, and the second feeding line 2110 is located at the other side of the second support plate 2112. The second feeder 2110 is for feeding energy to the fifth and seventh radiation arms 214 and 215. The second feed line 2110 is identical in structural design to the first feed line 218 and will not be described in detail here. The second feed line 2110 is independent from the first feed line 218.

It is to be understood that, for the coupling structure between two adjacent antenna elements of the mimo antenna 100, reference may be made to the coupling structure between the first antenna element 21 and other adjacent antenna elements (e.g., the second antenna element 22, the third antenna element 23, the fourth antenna element 24, etc.), and details thereof are not repeated herein.

The above description is only an embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and the changes or substitutions should be covered within the scope of the present invention; in the present invention, the embodiments and features of the embodiments may be combined with each other without conflict. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A MIMO antenna comprises a reflecting plate, a first antenna unit, a second antenna unit and a first decoupling connection line;

the first antenna unit comprises a first support erected on the reflecting plate and a first radiation arm positioned on the first support, the second antenna unit comprises a second support erected on the reflecting plate and a second radiation arm positioned on the second support, the first support and the second support are arranged adjacent to each other at intervals, and the polarization direction of the first radiation arm is the same as that of the second radiation arm; the first antenna unit and the second antenna unit respectively further comprise a connecting arm used for grounding the radiation arm and a feeder line used for feeding energy into the radiation arm;

the first decoupling connecting line comprises a first coupling section, a first transmission section, a first connecting section, a second transmission section and a second coupling section, the first connecting section is located on the reflecting plate, the first coupling section is located on the first support and coupled with the first radiation arm, the first transmission section is located on the first support and connected between the first coupling section and one end of the first connecting section, the second coupling section is located on the second support and coupled with the second radiation arm, and the second transmission section is located on the second support and connected between the second coupling section and the other end of the first connecting section.

2. The mimo antenna of claim 1, wherein the first decoupling trace further comprises a grounding segment, the grounding segment is disposed on the reflector, one end of the grounding segment is connected to the first connecting segment, and the other end of the grounding segment is grounded.

3. The mimo antenna of claim 1, wherein the first decoupling trace further comprises an open segment, the open segment is disposed on the reflector, one end of the open segment is connected to the first connecting segment, and the other end of the open segment is suspended.

4. A mimo antenna according to any of claims 1 to 3, wherein the first coupling section and the first radiating arm are located on opposite sides of the first support;

or, the first coupling section and the first radiating arm are located on the same side of the first support, and the first coupling section and the first radiating arm are arranged at an interval.

5. A mimo antenna according to any of claims 1 to 3, wherein the reflecting plate is a conductive plate, the conductive plate is grounded, and an insulating layer is disposed between the first connecting section and the reflecting plate.

6. A mimo antenna according to any of claims 1 to 3, wherein the reflector comprises an insulating substrate and a conducting strip located on a bottom side of the insulating substrate, the conducting strip is grounded, the first and second supports are fixed to the insulating substrate and located on a top side of the insulating substrate, and the first connecting section is located on the top side of the insulating substrate.

7. A mimo antenna according to any of claims 1 to 3, wherein the first antenna element further comprises a first connecting arm, the first connecting arm is located on the first support and has one end connected to the first radiating arm, and the other end of the first connecting arm is electrically connected to the ground of the reflector.

8. A mimo antenna according to any of claims 1 to 3, wherein the first antenna element further comprises a third radiating arm, the third radiating arm being located on the first support and spaced apart from the first radiating arm, the third radiating arm having a polarization direction identical to that of the first radiating arm so as to form a dipole element together with the first radiating arm;

the MIMO antenna also comprises a third antenna unit and a second decoupling connecting line;

the third antenna unit comprises a third support erected on the reflecting plate and a fourth radiation arm positioned on the third support, the third support and the first support are adjacent and arranged at intervals, the third support is positioned on one side of the first support, which is far away from the second support, and the polarization direction of the fourth radiation arm is the same as that of the third radiation arm;

the second decoupling connecting line comprises a third coupling section, a third transmission section, a second connecting section, a fourth transmission section and a fourth coupling section, the second connecting section is located on the reflecting plate, the third coupling section is located on the first support and coupled with the third radiating arm, the third transmission section is located on the first support and connected between the third coupling section and one end of the second connecting section, the fourth coupling section is located on the third support and coupled with the fourth radiating arm, and the fourth transmission section is located on the third support and connected between the fourth coupling section and the other end of the second connecting section.

9. A mimo antenna according to any of claims 1 to 3, wherein the first support comprises a first support plate and a second support plate perpendicular to the first support plate, the first radiating arm is located on the first support plate, the first antenna element further comprises a fifth radiating arm located on the second support plate, and a polarization direction of the fifth radiating arm is perpendicular to a polarization direction of the first radiating arm so as to form a dual-polarized element unit together with the first radiating arm;

the MIMO antenna also comprises a fourth antenna unit and a third decoupling connecting line;

the fourth antenna unit comprises a fourth support erected on the reflecting plate and a sixth radiation arm positioned on the fourth support, the fourth support and the first support are adjacent and arranged at intervals, and the polarization direction of the sixth radiation arm is the same as that of the fifth radiation arm;

the third decoupling connecting line comprises a fifth coupling section, a fifth transmission section, a third connecting section, a sixth transmission section and a sixth coupling section, the third connecting section is located on the reflecting plate, the fifth coupling section is located on the first support and coupled with the fifth radiation arm, the fifth transmission section is located on the first support and connected between the fifth coupling section and one end of the third connecting section, the sixth coupling section is located on the fourth support and coupled with the sixth radiation arm, and the sixth transmission section is located on the fourth support and connected between the sixth coupling section and the other end of the third connecting section.

10. A base station comprising a mimo antenna according to any of claims 1 to 9.