CN116404408A

CN116404408A - Base station antenna

Info

Publication number: CN116404408A
Application number: CN202310235804.9A
Authority: CN
Inventors: 许拓; 孙波; 汪振宇
Original assignee: CICT Mobile Communication Technology Co Ltd
Current assignee: CICT Mobile Communication Technology Co Ltd
Priority date: 2023-03-13
Filing date: 2023-03-13
Publication date: 2023-07-07

Abstract

The invention provides a base station antenna, and relates to the technical field of mobile communication. The base station antenna comprises a carrier, a parasitic radiation unit, a radiation unit module and a first PCB board, wherein the carrier is fixedly connected with the first PCB board, the parasitic radiation unit is fixed on the carrier, the radiation unit module is a microstrip patch formed on the first PCB board, and the radiation unit module and the parasitic radiation unit form a double-layer patch antenna. According to the base station antenna provided by the invention, the radiation unit module adopts the microstrip patch mode, and the parasitic radiation unit is added, so that the radiation performance is improved, the circuit index is optimized, and compared with the traditional radiation unit mode, the section height of the radiation unit is reduced by about 50%.

Description

Base station antenna

Technical Field

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

Background

Along with the continuous development of the mobile communication technology in China and the rapid increase of the user data flow, the application of the fifth generation mobile communication has first made breakthrough progress in China, and related upstream and downstream industries have also developed rapidly. Ultra-large-scale array antennas, one of the key technologies for 5G communication, are also rapidly applied to various macro base stations and small base stations. In order to further improve the coverage of indoor and outdoor high-temperature spots and meet the high-capacity requirement, 6G related research has been greatly advanced.

In order to meet the requirement of various applications in the 6G landscape, the antenna part serving as a signal receiving and transmitting medium needs to be further upgraded, and deep researches are conducted from the aspects of working frequency bands, array scale, beam forming algorithm and the like; and further, in order to satisfy commercialization applications, further weight saving and miniaturization are required in terms of structure.

Disclosure of Invention

The invention provides a base station antenna which is used for solving the defect of miniaturization design of a 6G radiating element in the prior art.

The invention provides a base station antenna which comprises a carrier, a parasitic radiation unit, a radiation unit module and a first PCB board, wherein the carrier is fixedly connected with the first PCB board, the parasitic radiation unit is fixed on the carrier, the radiation unit module is a microstrip patch formed on the first PCB board, and the radiation unit module and the parasitic radiation unit form a double-layer patch antenna.

According to the base station antenna provided by the invention, the base station antenna further comprises a second PCB, a third PCB and a feed network, wherein the first PCB and the third PCB are bonded together through the second PCB, the feed network comprises a first power divider and a second power divider, the first power divider is formed on the first PCB, the second power divider is formed on the third PCB, and the first power divider is electrically connected with the second power divider.

According to the base station antenna provided by the invention, the parasitic radiation unit is fixed on the front surface of the carrier.

According to the base station antenna provided by the invention, the parasitic radiation unit is fixed on the back surface of the carrier.

According to the base station antenna provided by the invention, the carrier is provided with the avoidance hole and the limiting piece, the connecting piece is arranged through the parasitic radiation unit and the avoidance hole so as to connect the parasitic radiation unit with the carrier, and the limiting piece is used for limiting the parasitic radiation unit.

According to the base station antenna provided by the invention, the limiting piece is provided with the guide surface, the bottom of the limiting piece is provided with the limiting groove, the guide surface is used for guiding the parasitic radiating element to move into the limiting groove, and the limiting groove is matched with the parasitic radiating element.

According to the base station antenna provided by the invention, the carrier is provided with the fixing hole, and the fixing piece is arranged in the fixing hole in a penetrating manner so as to fix the carrier on the first PCB.

According to the base station antenna provided by the invention, the carrier is provided with the first windowing corresponding to the parasitic radiation unit.

The base station antenna provided by the invention further comprises a debugging component, wherein a second window and a third window are arranged on the carrier, the debugging component comprises a first debugging component and a second debugging component, the first debugging component is fixed on the second window, and the second debugging component is fixed on the third window; the second window extends along the length direction of the carrier and is arranged between two adjacent rows of parasitic radiation units; the third window extends along the width direction of the carrier and is arranged between two adjacent columns of parasitic radiation units.

According to the base station antenna provided by the invention, the front surfaces of the second windowed and the third windowed are respectively provided with the clamping grooves, the first debugging component and the second debugging component are respectively provided with the protrusions, and the protrusions are matched with the corresponding clamping grooves.

According to the base station antenna provided by the invention, the radiation unit module adopts the microstrip patch mode, and the parasitic radiation unit is added, so that the radiation performance is improved, the circuit index is optimized, and compared with the traditional radiation unit mode, the section height of the radiation unit is reduced by about 50%.

Drawings

In order to more clearly illustrate the invention or the technical solutions of the prior art, the following description will briefly explain the drawings used in the embodiments or the description of the prior art, and it is obvious that the drawings in the following description are some embodiments of the invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a base station antenna provided by the present invention;

fig. 2 is an exploded view of a base station antenna provided by the present invention;

fig. 3 is a partially exploded view of a base station antenna provided by the present invention;

fig. 4 is a bottom view of a base station antenna provided by the present invention;

FIG. 5 is a schematic view of the structure of the carrier provided by the present invention;

FIG. 6 is a schematic view of the back structure of the carrier shown in FIG. 5;

FIG. 7 is a schematic view of a mounting structure of a carrier provided by the present invention;

fig. 8 is a top view of a base station antenna provided by the present invention;

FIG. 9 is a schematic diagram of a first debug feature provided by the present invention;

FIG. 10 is a top view of the first debug feature shown in FIG. 9;

FIG. 11 is a schematic diagram of a second debug feature provided by the present invention;

fig. 12 is a top view of the second debug feature shown in fig. 11.

Reference numerals:

10. a carrier; 11. avoidance holes; 12. a limiting piece; 13. a fixing hole; 131. reinforcing ribs; 14. a first window; 15. a second window; 16. a third window; 17. a clamping groove; 20. a parasitic radiating element; 30. a radiation unit module; 41. a first PCB board; 42. a second PCB board; 43. a third PCB board; 51. a first power divider; 52. a second power divider; 53. a metal rod; 60. a connecting piece; 71. a first debug component; 72. a second debug component; 73. a protrusion; 80. a radio frequency connector.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The features of the terms "first", "second", and the like in the description and in the claims of this application may be used for descriptive or implicit inclusion of one or more such features. In the description of the present invention, unless otherwise indicated, the meaning of "a plurality" is two or more. Furthermore, in the description and claims, "and/or" means at least one of the connected objects, and the character "/", generally means that the associated object is an "or" relationship.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

The conventional base station antenna is composed of an antenna array, a reflecting plate and a feed network, and the height of the antenna array is limited by the size of a radiating unit of the lowest working frequency band. In order to achieve a theoretical maximum radiation performance, the height of the radiating element is often designed to be a quarter wavelength height of the operating frequency band. The feed network is composed of a phase shifting module and a power dividing module, with the industrial development, the microstrip power divider based on the printed circuit is raised, the size of the power dividing module is further reduced, but the phase shifting module also greatly increases the space of the base station antenna.

With the continuous development of mobile communication technology, active antenna units are widely applied to 5G base stations, the section of an antenna array is greatly reduced, a phase shifting module is sunk to be designed at a device end, and the phase relation among the arrays is not adjusted by a traditional mechanical mode to realize beam forming. However, as the array scale increases substantially, the complexity of the circuit design at the device end is higher, more space is required, further sacrificing the height of the antenna end is required, and optimizing the low profile design of the antenna end is urgently needed.

On the other hand, in order to reduce the weight of the active antenna element, it is necessary to continuously reduce the components of the antenna end or to optimize the structural dimensions or to further promote the lightweight design by material improvement. With the increase of the working frequency band, the space between the radiating units is greatly reduced, and the design difficulty of the array and the feed network of the antenna end is greatly improved due to the miniaturization design requirements of light weight and low profile. Space between radiation units is reduced, and difficulty is brought to debugging of index standing waves and isolation of an antenna key circuit; in addition, from the aspect of batch production, the miniaturization of the module inevitably leads to the improvement of difficulty in assembly, the traditional base station antenna is more in assembly steps, and the welding points are more, so that the assembly procedure of the antenna needs to be optimized on the premise of ensuring performance indexes, and the operation steps are reduced.

The base station antenna of the present invention is described below in connection with fig. 1-12.

The present invention provides a base station antenna, as shown in fig. 1 and 2, comprising: carrier 10, parasitic radiating element 20, radiating element module 30, and first PCB board 41. The carrier 10 is fixedly connected with the first PCB 41, the parasitic radiation element 20 is fixed on the carrier 10, the radiation element module 30 is a microstrip patch formed on the first PCB 41, and a dual-layer patch antenna is formed by the parasitic radiation element 20 fixed on the carrier 10.

The carrier 10 is a plastic part, can be integrally injection molded, has a dielectric constant lower than 2.8, and can withstand high temperatures up to 100 ℃.

The parasitic radiating element 20 is a component having metallic characteristics or a component having partially metallic-like characteristics. During manufacturing, the parasitic radiating element 20 is prefabricated on the carrier 10 in advance by adopting an integral injection molding process, so that the production efficiency is greatly improved, and the mass production is facilitated. Alternatively, the parasitic radiating element 20 is a metallic conductor such as an aluminum sheet or copper sheet with a thickness. In addition, the parasitic radiation element 20 may be a copper-clad PCB, or an element with a metal characteristic may be grown on an industrial material such as plastic through a special process. Wherein, as shown in fig. 3, the projection profile of the parasitic radiating element 20 is rectangular. It should be noted that, the projection profile of the parasitic radiation element 20 may also be shaped, for example, the edge of the projection profile of the parasitic radiation element 20 is triangular saw-tooth or rectangular saw-tooth, and a hollow structure with a circular shape, a rectangular shape or a shaped shape is provided in the middle.

As shown in fig. 3, the microstrip patch has a rectangular shape. Similar to the parasitic radiating element 20, the edges of the radiating element module 30 may be triangular saw-tooth or rectangular saw-tooth with the middle copper-clad portion removed of the circular, rectangular or profiled copper-clad. The patch antenna is operated in a mode of + -45 DEG cross polarization excitation, and the excitation points are located at two corners on the same side of the microstrip patch carried on the first PCB 41.

According to the base station antenna provided by the invention, the radiating element module 30 adopts a microstrip patch mode, and the parasitic radiating element 20 is added to improve the radiating performance and optimize the circuit index, so that the section height of the radiating element is reduced by about 50% compared with the traditional radiating element mode.

In order to meet the miniaturization design requirement, the distance Lm between the parasitic radiation units 20 in the vertical direction is 0.6λ -0.8λ, the distance Ln in the horizontal direction is 0.4λ -0.6λ, and Δ is the equivalent wavelength of the center frequency in the PCB dielectric substrate in the operating frequency band.

The base station antenna further comprises a second PCB board 42, a third PCB board 43 and a feed network. The feed network includes a first power divider 51 and a second power divider 52, where the first power divider 51 and the second power divider 52 are electrically connected. The first PCB 41 and the third PCB 43 are bonded together through the second PCB 42, the first power divider 51 is formed on the first PCB 41, and the second power divider 52 is formed on the third PCB 43.

The first power divider 51 is formed on the first PCB 41 and is disposed coplanar with the radiation unit module 30 on the first PCB 41.

Specifically, the first power divider 51 is a two-power divider or a one-out N (N is greater than or equal to 2) microstrip power divider, and the second power divider 52 is a one-out four, one-out five or one-out N (N is greater than or equal to 2) microstrip power divider. As shown in fig. 3, the first power divider 51 is a microstrip two-power divider; as shown in fig. 4, the second power divider 52 is a four-out microstrip power divider. The distance between the parasitic radiation units 20 in the vertical direction is Lm, the phase difference between the two ports of the microstrip two-power divider is in a proportional relation with Lm, and the phase difference between the four ports of the microstrip two-power divider is in a proportional relation with two times Lm. It can be understood that the first-out-four microstrip power divider formed on the third PCB 43 can be split into two stages of microstrip power dividers.

Alternatively, as shown in fig. 3, the first power divider 51 and the second power divider 52 are electrically connected by a metal rod 53 having wire characteristics. Of course, the first power divider 51 and the second power divider 52 may be microstrip lines, and impedance thereof may be adjusted through simulation or actual measurement, so as to realize matching of the feed network.

The feed network further includes a radio frequency connector 80 that interfaces with the equipment end, the radio frequency connector 80 being electrically connected to the main feed port of the second power divider 52.

The four two power dividers are connected with the one-out four microstrip power dividers, so that one-out eight is realized. As shown in fig. 4, the ±45° polarization of the corresponding radiation unit in the feed network is two symmetrically arranged one eighth microstrip power divider. The spatial layout and the radiation unit are in the form of patches, and the layout position of the radio frequency connector 80 and the manner of the patches and the third PCB 43 are connected by using a multi-point surface mount. As shown in fig. 4, two radio frequency connectors 80 connected with two one-out-eight microstrip power splitters which are symmetrically arranged are arranged in a staggered manner.

The base station antenna provided by the embodiment of the invention directly depends on the printed circuit board, reduces the traditional reflecting plate parts, reduces the weight of the antenna by 30%, and ensures that the product consistency is better because the feed network is integrally designed in the multilayer PCB, and the traditional coaxial feeder welding procedure is eliminated.

Specifically, as shown in fig. 5 and 6, the carrier 10 is provided with an avoidance hole 11 and a limiting member 12, and the connecting member 60 is disposed through the parasitic radiating element 20 and the avoidance hole 11 so as to connect the parasitic radiating element 20 and the carrier 10 together. The limiter 12 serves to constrain the parasitic radiating element 20.

In an alternative embodiment, as shown in fig. 2, the parasitic radiating element 20 is secured to the back side of the carrier 10.

As shown in fig. 6, four limiting members 12 are provided corresponding to each parasitic radiating element 20, and the four limiting members 12 are arranged in a square shape. The limiting piece 12 is provided with a guiding surface, the bottom of the limiting piece 12 is provided with a limiting groove, the guiding surface is used for guiding the parasitic radiating element 20 to slide into the limiting groove, and the limiting groove is matched with the parasitic radiating element 20. When the parasitic element 20 moves to the bottom of the limiting member 12 along the guiding surface, and falls into the limiting groove, the parasitic element 20 is restrained on the back surface of the carrier 10 by the opposite groove walls of the limiting groove, and meanwhile, the parasitic element 20 is prevented from moving along the surface of the carrier 10 by the mutual cooperation of the four limiting members 12.

Alternatively, the connector 60 is a plastic rivet or screw. The connection 60 is fixed from the back of the carrier 10 through the parasitic radiating element 20.

In yet another alternative embodiment, as shown in fig. 7, the parasitic radiating element 20 is secured to the front side of the carrier 10, facilitating replacement of the parasitic radiating element 20.

As shown in fig. 7, the stopper 12 is provided on the front surface of the carrier 10. At this time, the connection member 60 such as a plastic rivet is fixed from the front surface of the carrier 10 through the parasitic radiating element 20.

In addition, as shown in fig. 2 and 7, the carrier 10 is further provided with a fixing hole 13, and a fixing member (not shown) is inserted into the fixing hole 13 to fix the carrier 10 to the first PCB 41.

The carrier 10 is provided with mounting posts on opposite sides thereof, respectively, and fixing holes 13 are provided on the mounting posts. In order to improve the connection stability, a reinforcing rib 131 is further arranged beside the mounting column.

Optionally, the fixing member is a metal screw, a plastic screw, a rivet, or the like. The fixing member passes through the fixing hole 13, the first PCB 41, the second PCB 42 and the third PCB 43 to fix the carrier 10 to the first PCB 41.

It should be noted that, to ensure that the parasitic element 20 is consistent with the first PCB 41, the mounting posts and the stiffener 131 are located on the same side of the carrier 10 as the parasitic element 20. As shown in fig. 2, when the parasitic radiating element 20 is fixed to the rear surface of the carrier 10, the mounting posts and the reinforcing ribs 131 extend toward the rear surface of the carrier 10. As shown in fig. 7, when the parasitic radiating element 20 is fixed to the front surface of the carrier 10, the mounting posts and the reinforcing ribs 131 extend toward the front surface of the carrier 10.

Specifically, the fixing hole 13 is provided near one side of the carrier 10. As shown in fig. 8, the base station antenna has two carriers 10, wherein one carrier 10 rotates 180 ° relative to the other carrier 10, so as to ensure that the fixing holes 13 of the two carriers are dislocated, thereby reducing the space occupied by the two carriers 10, and both carriers 10 can be fixed in the antenna module in a smaller space.

The carrier 10 is provided with a first window 14 corresponding to the parasitic radiating element 20 as a tuning antenna circuit and a pattern indicator.

As shown in fig. 6, the first window 14 has a quadrangular structure with a concave arc at one corner. Four first windows 14 are provided corresponding to the same parasitic element 20, and the four first windows 14 are arranged around the circumference of the avoidance hole 11. The spacing posts are disposed between two adjacent first fenestrations 14.

The base station antenna further comprises a commissioning component. As shown in fig. 6, the carrier 10 is provided with a second window 15 and a third window 16. As shown in fig. 8, the debug unit includes a first debug unit 71 and a second debug unit 72. The first debug member 71 is fixed to the second window 15, and the second debug member 72 is fixed to the third window 16. Wherein the second fenestration 15 extends along the length of the carrier 10 and is disposed between two adjacent rows of parasitic radiating elements 20. The third windows 16 extend in the width direction of the carrier 10 and are provided between two adjacent columns of parasitic radiating elements 20.

Wherein the tuning components are fixed to the carrier 10, arranged in the gaps between the parasitic radiating elements 20 in the vertical and horizontal directions. The debugging component, the carrier 10 and the parasitic radiating element 20 can also be used as a debugging module of antenna performance, can optimize along with the size of the parasitic radiating element 20 and optimally design the relative position of the microstrip patch, and has high substitution and flexible disassembly.

The second window 15 and the third window 16 are used for debugging circuit indexes of the antenna, and the circuit indexes with larger influence factors are isolation indexes.

The front sides of the second opening window 15 and the third opening window 16 are respectively provided with a clamping groove 17, the first debugging component 71 and the second debugging component 72 are respectively provided with a bulge 73, and the bulge 73 is matched with the corresponding clamping groove 17.

As shown in fig. 5, the front surfaces of the second window 15 and the third window 16 are respectively provided with two clamping grooves 17. As shown in fig. 9 to 12, two protrusions 73 are provided along the length direction of the first debug member 71, and the two protrusions 73 are provided in one-to-one correspondence with the two clamping grooves 17 on the second window 15. Two protrusions 73 are also provided on the second adjustment part 72 to fit into the slots 17 on the third window 16. The position and the size of the card slot 17 may be set as required, and the present invention is not particularly limited to the position and the size of the card slot 17.

As shown in fig. 9 and 10, the first debug part 71 has a length L1 and a height H1. As shown in fig. 11 and 12, the second debug part 72 has a length L2 and a height H2. Wherein, H1 and H2 cannot be larger than the distance between the lower surface of the carrier 10 and the upper surface of the first PCB 41, L1 is smaller than the maximum edge spacing of the two parasitic radiating elements 20, and L2 is smaller than the side length of the parasitic radiating element 20. The dimensions of the tuning components are not limited to those described in this example and may be based on the space and performance tuning of the base station antenna.

Alternatively, the adjustment member is independent of the carrier 10, or the adjustment member is injection molded integrally with the carrier 10, so as to improve the production efficiency. The debugging component is determined according to the debugging performance of the base station antenna, and only the debugging component has metal conductive properties.

The isolation between the radiation units is optimized by changing the mutual coupling between the units by introducing the isolation strips with metal properties between the radiation units so as to change the isolation between the system ports, and the base station antenna provided by the embodiment of the invention optimizes the isolation index by reserving the second window and the third window on the carrier 10 formed by integral injection molding so as to install the first debugging component 71 and the second debugging component 72, and can also be used for adjusting the standing waves.

The base station antenna comprises M double-layer patch antennas in the vertical direction and N double-layer patch antennas in the horizontal direction. As shown in fig. 1, m=8, n=3, constituting a 3×8 array of small cells.

In order to achieve a pre-formed downtilt angle in the maximum radiation direction of the base station antenna, different phase values need to be input to each dual-layer patch antenna. In the embodiment of the invention, the microstrip line length of the feed network is changed, so that a fixed phase difference relation is formed between the main feed port and the split port of the eight-microstrip power divider, and the maximum radiation direction of the synthesized beam of 8 radiation units meets the preset downtilt angle through the principle of directional diagram product.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. The base station antenna is characterized by comprising a carrier, a parasitic radiation unit, a radiation unit module and a first PCB board, wherein the carrier is fixedly connected with the first PCB board, the parasitic radiation unit is fixed on the carrier, the radiation unit module is a microstrip patch formed on the first PCB board, and the radiation unit module and the parasitic radiation unit form a double-layer patch antenna.

2. The base station antenna of claim 1, further comprising a second PCB, a third PCB, and a feed network, wherein the first PCB and the third PCB are bonded together by the second PCB, the feed network comprises a first power divider and a second power divider, the first power divider is formed on the first PCB, the second power divider is formed on the third PCB, and the first power divider and the second power divider are electrically connected.

3. The base station antenna of claim 1, wherein the parasitic radiating element is fixed to a front face of the carrier.

4. The base station antenna of claim 1, wherein the parasitic radiating element is secured to a back side of the carrier.

5. The base station antenna according to claim 1, 3 or 4, wherein the carrier is provided with a hole for avoiding and a limiting member, the connecting member is arranged through the parasitic radiating element and the hole for avoiding so as to connect the parasitic radiating element and the carrier together, and the limiting member is used for limiting the parasitic radiating element.

6. The base station antenna of claim 5, wherein the limiting member has a guiding surface, a limiting groove is formed in a bottom of the limiting member, the guiding surface is used for guiding the parasitic radiating element to move into the limiting groove, and the limiting groove is adapted to the parasitic radiating element.

7. The base station antenna of claim 1, wherein the carrier is provided with a fixing hole, and the fixing member is inserted through the fixing hole to fix the carrier to the first PCB.

8. The base station antenna of claim 1, wherein the carrier is provided with a first window corresponding to the parasitic radiating element.

9. The base station antenna of claim 1, further comprising a tuning component, wherein the carrier is provided with a second window and a third window, the tuning component comprises a first tuning component and a second tuning component, the first tuning component is fixed to the second window, and the second tuning component is fixed to the third window; the second window extends along the length direction of the carrier and is arranged between two adjacent rows of parasitic radiation units; the third window extends along the width direction of the carrier and is arranged between two adjacent columns of parasitic radiation units.

10. The base station antenna of claim 9, wherein the front sides of the second and third windows are respectively provided with a slot, and the first and second debug members are respectively provided with a protrusion, the protrusion being adapted to the corresponding slot.