Broadband expansion parasitic layer dual-polarization base station antenna radiation unit and assembling method thereof

Abstract

The invention discloses a broadband expansion parasitic layer dual-polarization base station antenna radiation unit and an assembling method thereof, and belongs to the technical field of antennas. The radiation unit comprises a reflecting plate, a zinc alloy metal support, two coaxial feeder lines and a double-layer PCB oscillator radiation surface. Bending structures are arranged on the two sides of the reflecting plate, and the zinc alloy metal support fixes the radiating surface of the double-layer PCB oscillator through the supporting columns and achieves electric connection. The radiating surface of the lower-layer PCB oscillator is a double-sided copper-clad plate; the radiating surface of the upper-layer PCB oscillator is a broadband expansion parasitic layer of which one side is coated with copper, and the working frequency band is expanded through electromagnetic coupling with the radiating surface of the lower-layer PCB oscillator. According to the antenna, a double-layer PCB structure and a specific parasitic layer design are adopted, on the premise that the structural complexity and cost are not remarkably increased, ultra-wideband coverage is achieved, and meanwhile good impedance matching, radiation pattern stability and dual polarization performance are guaranteed by optimizing the reflecting plate, the radiation arm microstructure and the feed mode.

Description

Technical Field

[0001] This application relates to the field of antenna technology, and in particular to a broadband extended parasitic layer dual-polarized base station antenna radiating element and its assembly method. Background Technology

[0002] As mobile communication technology continues to evolve from 4G to 5G and even the future 6G, the demands for network capacity, transmission speed, and connection density are constantly increasing. This requires base station antennas to support wider operating frequency bands to be compatible with more communication standards and frequency band resources. Currently, mobile communication systems urgently need to cover a broad spectrum from 1.4GHz to 2.7GHz, among which low-frequency band resources such as 1.4GHz are of great significance for expanding network coverage and improving signal penetration.

[0003] Traditional base station antenna radiating elements, such as single-layer dipole antennas or microstrip patch antennas, have bandwidth performance limited by their structural principles, making it difficult to achieve wideband coverage. A typical traditional design can only effectively cover the 1.7GHz–2.7GHz frequency band, with an absolute bandwidth of approximately 1GHz and a relative bandwidth of approximately 45.45%, which cannot meet the coverage requirements of the 1.4GHz low-frequency band and is difficult to adapt to the future trend of broadband network development.

[0004] To address the issue of insufficient bandwidth, various bandwidth extension schemes have been proposed in existing technologies, mainly including the use of multi-layer stacked resonant structures, loading multiple parasitic radiating elements, and designing complex coupled feed networks. However, these schemes generally suffer from significant drawbacks: multi-layer stacked structures significantly increase the vertical profile height of the antenna, which is detrimental to the concealed deployment and lightweight design of base station antennas; loading multiple parasitic elements leads to structural complexity, increasing the requirements for processing precision and manufacturing costs; complex coupled feed networks are not only difficult to design but may also introduce additional signal loss, degrading the antenna's radiation efficiency. More importantly, these existing schemes struggle to achieve a good balance between bandwidth, gain, pattern stability, cross-polarization performance, and manufacturing cost when achieving ultra-wideband coverage of 1.4GHz–2.7GHz (absolute bandwidth 1.3GHz, relative bandwidth approximately 63.41%), presenting significant technical bottlenecks.

[0005] Therefore, there is an urgent need for a new type of base station antenna radiating element that is simple in structure, easy to manufacture, cost-controllable, and can achieve significant bandwidth expansion, so as to overcome the shortcomings of existing technologies, achieve effective coverage of the 1.4GHz–2.7GHz frequency band, and at the same time ensure excellent radiation performance and engineering practicality. Summary of the Invention

[0006] This invention addresses the limitations of traditional base station antenna radiating elements in bandwidth and the problems of complex structure, high cost, and performance imbalance in existing broadband extension schemes, achieving simple and efficient coverage of the 1.4GHz-2.7GHz ultra-wideband. The technical solution is as follows: On the one hand, a broadband extended parasitic layer dual-polarized base station antenna radiating element is provided, comprising: A reflector (1) has a bent structure on both sides; A zinc alloy metal support (2) is set above the reflector (1). The bottom of the zinc alloy metal support (2) is provided with a fixing hole and a wire hole, and the upper part is provided with two support columns (16, 17). Two coaxial feed wires (3) pass through the wire hole at the bottom of the zinc alloy metal support (2), and their outer conductors are welded to the bottom of the zinc alloy metal support (2). The double-layer PCB oscillator radiating surface includes an upper PCB oscillator radiating surface (4) and a lower PCB oscillator radiating surface (5). The double-layer PCB oscillator radiating surface is fixed and electrically connected by the support columns (16, 17) of the zinc alloy metal support (2). The upper PCB oscillator radiating surface (4) is a broadband extended parasitic layer, and the lower PCB oscillator radiating surface (5) is the radiating body. The lower PCB oscillator radiating surface (5) is connected to the positive and negative copper surfaces through metallized vias (7), and the upper PCB oscillator radiating surface (4) and the lower PCB oscillator radiating surface (5) achieve frequency band extension through electromagnetic coupling.

[0007] Optionally, both the upper PCB oscillator radiating surface (4) and the lower PCB oscillator radiating surface (5) are made of FR4 epoxy resin board with a dielectric constant of 4.4, a loss tangent Tanδ of 0.02, and a copper cladding thickness of 0.035 mm. The lower PCB oscillator radiating surface (5) is a double-sided copper-clad board with a thickness of 1 mm, and the upper PCB oscillator radiating surface (4) is a single-sided copper-clad board with a thickness of 0.6 mm, with copper foil printed on the side facing the lower PCB oscillator radiating surface (5).

[0008] Optionally, the lower PCB oscillator radiation surface (5) includes a front copper foil surface (6), a metallized via (7), a PCB board (8), and a back copper foil surface (9). The front copper foil surface (6) and the back copper foil surface (9) have a four-leaf symmetrical structure, and four radial arms extend out along the ±45° direction. The ends of the radial arms are provided with a tooth-like structure. Each radiating arm is provided with several metallized vias (7), the inner wall of which is covered with copper to connect the front copper foil surface (6) and the back copper foil surface (9). Each radiating arm has a flat, oval-shaped hollow groove inside, from which a thin, straight branch extends.

[0009] Optionally, the diameter of the metallized via (7) is 1.2 mm–3 mm; The PCB board (8) is square with a side length of 1.15λ1-1.3λ1, where λ1 is the wavelength corresponding to the lowest frequency.

[0010] Optionally, the upper PCB oscillator radiation surface (4) includes a PCB board (10) and a reverse copper foil surface (11). The reverse copper foil surface (11) is a single-sided copper-clad surface facing the radiating surface (5) of the lower PCB oscillator; The side length of the PCB board (10) is the same as that of the PCB board (8); The reverse copper foil surface (11) includes four sets of symmetrically distributed inner and outer arcs and quasi-square structures at the four corners. The widths of the inner and outer arcs are 0.6mm-1.5mm and 1mm-2mm, respectively, and the arc angles are 16-19°. The quasi-square structure has a circular hollow inside.

[0011] Optionally, the support columns (16, 17) of the zinc alloy metal support (2) pass through the lower PCB board (8) and are welded to the radiating arm; The total height of the zinc alloy metal support (2) is 0.25λ2-0.3λ2, where λ2 is the wavelength corresponding to the center frequency, and the thickness of the base is 1mm-3mm.

[0012] Optionally, the coaxial feed line (3) has a characteristic impedance of 50Ω. Its outer conductor is welded to the bottom of the zinc alloy metal support (2), and its inner conductor passes through the support column (16, 17) and is welded to the feed point at the end of the corresponding radiating arm of the lower PCB oscillator radiation surface (5) to achieve balanced feeding.

[0013] Optionally, the reflector (1) has a thickness of 1.5mm-2.5mm and a side length of 0.9λ1-1.3λ1, where λ1 is the wavelength corresponding to the lowest frequency; The height of the bending structure on both sides of the reflector (1) is 10mm–30mm.

[0014] Optionally, the radiating unit is composed of two mutually perpendicular dipoles, each dipole consisting of a pair of diagonally oriented metal microstrip line radiating arms and corresponding metallized vias (7), corresponding to two polarization directions of ±45° respectively; When the lower PCB oscillator radiating surface (5) works independently, it covers the 1.7GHz–2.7GHz frequency band. After the upper PCB oscillator radiating surface (4) is superimposed, the working frequency band of the radiating unit is extended to 1.4GHz–2.7GHz.

[0015] On the other hand, a method for assembling a broadband extended parasitic layer dual-polarized base station antenna radiating element is provided, the method comprising: Place the reflector (1) horizontally and fix the zinc alloy metal support (2) to the center of the reflector (1) with screws, ensuring that the wire hole of the zinc alloy metal support (2) faces the PCB. Align the lower PCB oscillator radiation surface (5) with the support column (16, 17) of the zinc alloy metal support (2) and pass through and fix it so that the support column (16, 17) is welded and fixed to the radiation arm of the lower PCB oscillator radiation surface (5). The upper PCB oscillator radiation surface (4) is placed parallel to the lower PCB oscillator radiation surface (5) with the copper foil facing the lower PCB oscillator radiation surface (5) and aligned with the center. The spacing is fixed by using an insulating medium. Two coaxial feed wires (3) with a characteristic impedance of 50Ω are passed through the wire holes at the bottom of the zinc alloy metal support (2). Their outer conductors are welded to the bottom of the zinc alloy metal support (2), and their inner conductors are welded to the feed point at the end of the corresponding radiating arm of the lower PCB oscillator radiation surface (5) after passing through the support column (16, 17). The assembled radiating unit is debugged until the voltage standing wave ratio is less than 1.45 in the 1.4GHz–2.7GHz frequency band, and the assembly is completed.

[0016] Therefore, compared with the prior art, this application achieves at least the following technical effects.

[0017] This invention discloses a broadband extended parasitic layer dual-polarized base station antenna radiating unit, relating to the field of antenna technology. The radiating unit includes a reflector (1), a zinc alloy metal support (2), two coaxial feed lines (3), and a double-layer PCB radiating surface (composed of an upper PCB radiating surface (4) and a lower PCB radiating surface (5)). The reflector (1) has a bent structure on both sides. The zinc alloy metal support (2) fixes the double-layer PCB radiating surface and achieves electrical connection through support columns (16, 17). The lower PCB radiating surface (5) is a double-sided copper-clad plate, which connects the front and back copper foil surfaces through metallized vias (7) to form a radiating body covering the 1.7GHz-2.7GHz frequency band. The upper PCB radiating surface (4) is a single-sided copper-clad broadband extended parasitic layer, which extends the operating frequency band to 1.4GHz-2.7GHz through electromagnetic coupling with the lower PCB radiating surface (5). This invention employs a double-layer PCB structure and a specific parasitic layer design, achieving ultra-wideband coverage without significantly increasing structural complexity and cost. At the same time, by optimizing the microstructure of the reflector and radiating arm and the power supply method, it ensures good impedance matching, radiation pattern stability and dual polarization performance, making it suitable for the broadband deployment requirements of mobile communication base stations.

[0018] In addition, by electromagnetic coupling between the upper PCB parasitic layer and the lower main radiator, a new low-frequency resonant point is excited, extending the operating frequency band from 1.7GHz-2.7GHz to 1.4GHz-2.7GHz, with an absolute bandwidth of 1.3GHz and a relative bandwidth of 63.41%, covering more communication standards; In addition, the use of PCB material and double-layer compact design makes it lighter and smaller than traditional metal die-casting structure. The PCB process can realize complex microstructures, which can meet the needs of concealed deployment of base station antennas. In addition, through the collaborative design of the reflector bending structure, the hollowed-out groove of the radiation arm and the thin straight branches and the parasitic layer arc structure, the impedance matching (VSWR<1.45), radiation pattern stability and cross-polarization purity are optimized, while the dual-polarization structure ensures good port isolation. In addition, using common materials such as FR4 epoxy resin boards and standard PCB etching processes, mass production has good consistency and low cost; when damaged, the PCB module can be replaced individually, making maintenance more convenient than traditional metal die-cast structures. Attached Figure Description

[0019] Figure 1 This is a front view of the overall structure of the radiating unit; Figure 2 This is a side view of the overall structure of the radiating unit; Figure 3 This is an exploded view of the radiating surface of a double-layer PCB oscillator. Figure 4This is a top view of the radiating surface of the lower PCB oscillator. Figure 5 This is a top view of the radiating surface of the upper PCB oscillator. Figure 6 Side view of the zinc alloy metal support; Figure 7 The VSWR curve of the dual-polarization voltage after adding the parasitic layer; Figure 8 To further extend the parasitic layer, the port isolation curve is shown. Figure 9 The center frequency dual-polarization gain pattern after adding the extended parasitic layer; Figure 10 The diagram shows the principal polarization and cross-polarization curves of the center frequency vertical plane after adding the parasitic layer; Figure 11 The diagram shows the central frequency horizontal plane principal polarization and cross-polarization curves after adding the parasitic layer; Figure 12 The VSWR curve is shown for the dual-polarization voltage without extended parasitic layer. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0021] In this article, "multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0022] Example 1 This embodiment provides a broadband extended parasitic layer dual-polarized base station antenna radiating element, specifically including: The reflector 1 is made of aluminum with a thickness of 2.0mm (within the range of 1.5mm-2.5mm) and a side length of 1.2λ1 (λ1 is the wavelength corresponding to 1.4GHz, approximately 214.29mm). It has a bending structure with a height of 20mm (within the range of 10mm-30mm) on both sides, with the bending direction perpendicular to the main plane of the reflector. It is made by bending and surface conductive treatment.

[0023] The zinc alloy metal support 2 is fixed to the center of the reflector 1 with screws. It has two fixing holes (for connecting to the reflector) and two wire holes (for coaxial feed wires to pass through) at the bottom. It has two parallel support columns 16 and 17 at the top. The total height is 0.28λ2 (λ2 is the wavelength corresponding to the center frequency of 2.05GHz, about 146.34mm). The thickness of the base is 2mm (within the range of 1mm-3mm).

[0024] The coaxial feeder 3 has a characteristic impedance of 50Ω. It passes through two wire holes at the bottom of the zinc alloy metal support 2. The outer conductor is welded to the bottom of the zinc alloy metal support 2 and the inner conductor extends to the top of the support columns 16 and 17.

[0025] The double-layer PCB oscillator radiating surface includes an upper PCB oscillator radiating surface 4 and a lower PCB oscillator radiating surface 5, which are aligned at the center. They are fixed by welding after passing through the mounting holes of the lower PCB oscillator radiating surface 5 with support columns 16 and 17, thus achieving mechanical fixation and electrical connection. The upper PCB oscillator radiating surface 4 is a broadband extension parasitic layer and is not directly connected to the power supply system. The lower PCB oscillator radiating surface 5 is the radiating body and is connected to the positive and negative copper surfaces through metallized vias 7.

[0026] like Figure 1 As shown, the overall structure is axially symmetrically distributed. The reflector 1 is the bottom supporting structure, the zinc alloy metal support 2 stands vertically at the center of the reflector, the double-layer PCB oscillator radiation surface is horizontally set at the top of the support column, and the coaxial feed line 3 passes through the support from below the reflector and connects to the lower PCB oscillator radiation surface 5.

[0027] Figure 2 As shown in the side view, the bent structure of the reflector 1 protrudes from both sides of the main body. The height of the zinc alloy metal support 2 ensures a reasonable distance between the radiating surface of the double-layer PCB oscillator and the reflector, thus avoiding electromagnetic interference.

[0028] Figure 6 The spacing and diameter of the support columns 16 and 17 of the zinc alloy metal support 2 are adapted to the installation requirements of the PCB board, and the diameter of the bottom wire hole matches the outer conductor diameter of the coaxial feeder 3 to ensure the sealing and fixation after installation.

[0029] The basic structural design in this embodiment achieves excellent performance through the synergistic effect of three core structures: The bending structure of reflector 1 changes the electromagnetic wave reflection path. Compared with a planar reflector, it can effectively compress the beamwidth, improve the forward gain, and reduce the backward radiation loss, thus meeting the directional requirements of base station antenna arrays. The zinc alloy metal support 2 combines structural strength and electromagnetic shielding. Its material properties ensure the stability of the support while preventing external electromagnetic signals from interfering with the power supply system. The double-column design of support columns 16 and 17 ensures that the radiation surface of the double-layer PCB oscillator is subjected to uniform force, reducing assembly deformation. The compact layout and electrical connection of the double-layer PCB oscillator radiating surface provide a basis for the electromagnetic coupling between the upper parasitic layer and the lower main radiator. The spacing is controlled within the thickness of a single-layer microstrip line (0.035mm), reducing coupling loss and simplifying the overall structure, which is conducive to lightweight deployment. The balanced power supply design of the 50Ω coaxial feeder provides a stable energy input for dual polarization, and the welding fixation of the outer conductor and zinc alloy support enhances the reliability of the electrical connection and reduces signal transmission loss.

[0030] Example 2 This embodiment further discloses detailed features based on embodiment 1, as follows.

[0031] Furthermore, both the upper PCB oscillator radiating surface 4 and the lower PCB oscillator radiating surface 5 are made of FR4 epoxy resin board with a dielectric constant of 4.4, a loss tangent Tanδ of 0.02, and a copper cladding thickness of 0.035mm. The lower PCB oscillator radiating surface 5 is a double-sided copper clad board with a thickness of 1mm, and the upper PCB oscillator radiating surface 4 is a single-sided copper clad board with a thickness of 0.6mm. The copper foil is printed on the side facing the lower layer.

[0032] Details of the lower PCB oscillator radiation surface 5, such as Figure 4 As shown, it includes a front copper foil surface 6, metallized vias 7, a PCB board 8, and a back copper foil surface 9. The front copper foil surface 6 and the back copper foil surface 9 have a four-leaf symmetrical structure, extending four radiating arms along the ±45° direction. The ends of the radiating arms are provided with three tooth-like structures (for optimizing impedance matching). Each radiating arm has four metallized vias 7 evenly distributed, with a diameter of 2mm (within the range of 1.2mm-3mm), and the inner wall is copper-clad to achieve electrical connection between the front and back copper foil surfaces. Each radiating arm has a flat elliptical hollow groove with a major axis of 15mm and a minor axis of 8mm. A thin straight branch with a length of 10mm and a width of 0.4mm extends from the groove, and the thin straight branch forms a 30° angle with the main body of the radiating arm.

[0033] Among them, PCB board 8 is square with a side length of 1.25λ1 (approximately 267.86mm), which is the same as the side length of PCB board 10 on the upper layer PCB.

[0034] Details of the upper PCB oscillator radiation surface 4, such as Figure 5As shown, it includes a PCB board 10 and a reverse copper foil surface 11; the reverse copper foil surface 11 includes four sets of symmetrically distributed inner and outer arcs and four quasi-square structures at the corners. The width of the inner arc is 1.0mm (within the range of 0.6mm-1.5mm), the width of the outer arc is 1.5mm (within the range of 1mm-2mm), and the arc angle is 18° (within the range of 16-19°); the side length of the quasi-square is 25mm, and there is a circular cutout with a diameter of 5mm inside. The four quasi-squares correspond to the diagonal direction of the lower radiating arm, and the total length after extension is 108.71mm (close to half the wavelength of 107.14mm corresponding to 1.4GHz).

[0035] Furthermore, the dual-polarization structure is composed of two mutually perpendicular dipoles through the radiating unit. Each dipole consists of a pair of diagonally oriented metal microstrip line radiating arms and corresponding metallized vias 7, corresponding to the two polarization directions of ±45°, and corresponding one-to-one with the two coaxial feed lines 3.

[0036] like Figure 7 As shown, the structural design of this embodiment ensures that, after loading the parasitic layer, the voltage standing wave ratio (VSWR) of both polarizations in the 1.4GHz-2.7GHz frequency band is below 1.45, reflecting excellent impedance matching; furthermore, Figure 8 The results show that the isolation is below -30dB across the wide bandwidth, indicating low signal interference between the two polarization ports. Figure 9-11 The gain patterns in the vertical and horizontal planes at the center frequency, as well as the characteristics of the main polarization and cross-polarization, are shown respectively. It can be seen that the beamwidth is uniform and the signal intensity of the cross-polarization is significantly lower than that of the main polarization, ensuring the stability of the radiation pattern and the purity of the signal. Figure 12 In contrast, without the parasitic layer, the VSWR at the low-frequency end increases sharply, and the effective frequency band ends at 1.7 GHz, highlighting the frequency band extension effect of the upper parasitic layer.

[0037] In summary, the detailed feature design of this embodiment optimizes performance from three dimensions: material, structure, and size, with the following results.

[0038] Firstly, the material selection is reasonable. The dielectric constant of FR4 epoxy resin board, 4.4, is in the ideal balance range, which achieves both moderate size reduction (keeping the PCB board side length within the practical range) and avoids bandwidth reduction and increased loss caused by excessively high dielectric constant. At the same time, FR4 material has mature technology, low cost, and is suitable for mass production; the copper thickness of 0.035mm ensures conductivity while reducing the overall weight of the PCB board. Furthermore, in the lower-layer radiating arm microstructure, the flat elliptical slots force the surface current to circumvent, increasing the effective electrical length of the current, reducing the physical size, and simultaneously breaking the uniform current distribution, suppressing high-order modes in the high-frequency band, and improving the stability of the radiation pattern; the thin straight stubs, acting as microstrip resonators, work synergistically with the distributed capacitance of the slots to couple multiple resonant modes, resulting in a continuous and flat response in the 1.7GHz-2.7GHz frequency band; the metallized vias 7 ensure reliable electrical connection between the positive and negative copper foil surfaces, improving radiation efficiency; In addition, in the design of the upper parasitic layer, four sets of symmetrical circular arcs enhance the coupling strength with the lower main radiator, ensuring effective energy transfer and improving the standing wave ratio; the quasi-square structure extends the equivalent length of the radiating arm, accurately exciting the resonant point near 1.4 GHz, and combining with the original resonant mode of the lower layer to achieve frequency band expansion; the circular hollow optimizes the current distribution and avoids performance degradation caused by local current concentration. In addition, the dipole design in the ±45° direction in the dual-polarization structure is adapted to the dual-polarization communication requirements of the base station antenna. The two polarization ports are independent of each other and have excellent isolation, avoiding signal crosstalk and ensuring communication quality. The toothed structure at the end of the radiating arm further optimizes impedance matching, keeping the VSWR stable over a wide bandwidth.

[0039] Example 3 This embodiment provides a method for assembling the above-mentioned broadband extended parasitic layer dual-polarized base station antenna radiating element, and the specific steps are as follows.

[0040] S1, the reflector is fixed to the support.

[0041] Place the reflector 1 horizontally on the tooling platform, ensuring the bent structure faces upwards. Secure it to the center of the reflector 1 using screws that pass through the fixing holes at the bottom of the zinc alloy metal support 2, and tighten the torque to 5N. m, ensuring the support is vertical and without tilt (e.g.) Figure 1 , Figure 6 (as shown) S2, lower PCB mounting.

[0042] Remove the radiating surface 5 of the lower PCB oscillator, so that the copper foil surface 6 faces upward. Align the support columns 16 and 17 of the zinc alloy metal support 2 through the mounting holes of the PCB board 8. After adjusting the PCB board to be level, weld the tops of the support columns 16 and 17 to the solder points of the radiating arm to fix them in place. Control the soldering temperature at 280℃-300℃ and the soldering time at 3-5 seconds (e.g., ...). Figure 3 , Figure 4 (as shown) S3, upper PCB mounting.

[0043] Take the upper PCB oscillator radiating surface 4, align the reverse copper foil surface 11 with the lower PCB oscillator radiating surface 5, and center them. Then, place a 0.035mm thick insulating pad between the two PCB layers and fix them using adhesive bonding, ensuring that the spacing between the two PCB layers is uniform and there is no misalignment or contact (e.g., Figure 3 , Figure 5 (as shown) S4, feeder cable connection.

[0044] Two 50Ω coaxial feed wires 3 are passed through the wire holes at the bottom of the zinc alloy metal support 2. The outer conductor is welded to the welding point at the bottom of the support. The inner conductor passes through the internal channels of the support columns 16 and 17 and is welded to the feed point at the end of the corresponding radiating arm of the lower PCB oscillator radiating surface 5. After welding, the solder joint is wrapped with insulating tape (e.g., ...). Figure 2 (as shown) S5, debugging and testing.

[0045] Connect the assembled radiating element to a vector network analyzer and perform scanning tests in the 1.0GHz-3.0GHz frequency band. Adjust the welding position of the feed line and the fixing accuracy of the upper PCB to ensure that the voltage standing wave ratio is less than 1.45 in the 1.4GHz-2.7GHz frequency band and the isolation between the two polarization ports is less than -22dB. Assembly is then complete. Figure 7 , Figure 8 (As shown).

[0046] Therefore, the assembly method provided in this embodiment can ensure the performance stability of the radiating unit, with the following effects.

[0047] In step 1, a tooling platform is used to ensure the vertical accuracy of the reflector and the support. In steps 2-3, the spacing and parallelism of the two PCB layers are controlled by center alignment and insulating pads to avoid electromagnetic coupling imbalance caused by assembly deviation and ensure the frequency band extension effect. The screw fixing of the support and reflector, the welding of the support column to the PCB, and the double-point welding of the feed line (outer conductor to support, inner conductor to radiating arm) enhance the structural stability and electrical connection reliability, and reduce the performance degradation caused by vibration or environmental changes. The control of soldering temperature and time is adapted to the PCB material and copper thickness to avoid high temperature damage to the PCB board or copper peeling; the use of insulating pads ensures the insulation of the two PCB layers, while precisely controlling the coupling spacing to reduce coupling loss. The process logic does not require complex special equipment, is compatible with mass assembly on production lines, and the debugging steps are specifically optimized for VSWR and isolation to ensure the performance consistency of each radiating unit and reduce the defect rate. During assembly, each component is fixed independently. If a PCB module is damaged later, it can be disassembled and replaced individually without the need for overall disassembly, thus reducing maintenance costs and downtime.

[0048] Those skilled in the art will understand that all or part of the steps of the above embodiments can be implemented by hardware, or by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as a read-only memory, a disk, or an optical disk. The above descriptions are merely optional embodiments of this application and are not intended to limit the application. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A broadband extended parasitic layer dual-polarized base station antenna radiating element, characterized in that, include: A reflector (1) has a bent structure on both sides. The reflector (1) has a thickness of 1.5mm-2.5mm and a side length of 0.9λ1-1.3λ1, where λ1 is the wavelength corresponding to the lowest frequency. The height of the bent structure on both sides of the reflector (1) is 10mm-30mm. A zinc alloy metal support (2) is set above the reflector (1). The bottom of the zinc alloy metal support (2) is provided with fixing holes and wire holes, and the upper part is provided with two support columns (16, 17). The total height of the zinc alloy metal support (2) is 0.25λ2-0.3λ2, where λ2 is the wavelength corresponding to the center frequency. The thickness of the base is 1mm-3mm. The support columns (16, 17) are used to fix and electrically connect the radiation surface of the double-layer PCB oscillator. Two coaxial feed wires (3) pass through the wire hole at the bottom of the zinc alloy metal support (2). The outer conductor of the coaxial feed wire (3) is welded to the bottom of the zinc alloy metal support (2). The characteristic impedance of the coaxial feed wire (3) is 50Ω. The outer conductor of the coaxial feed wire (3) is welded to the bottom of the zinc alloy metal support (2). The inner conductor passes through the support column (16, 17) and is welded to the feed point at the end of the corresponding radiating arm of the lower PCB oscillator radiating surface (5) to achieve balanced feeding. The double-layer PCB oscillator radiating surface includes an upper PCB oscillator radiating surface (4) and a lower PCB oscillator radiating surface (5). The double-layer PCB oscillator radiating surface is fixed and electrically connected by the support columns (16, 17) of the zinc alloy metal support (2). The upper PCB oscillator radiating surface (4) is a broadband extended parasitic layer, and the lower PCB oscillator radiating surface (5) is the radiating body. Both the upper PCB oscillator radiating surface (4) and the lower PCB oscillator radiating surface (5) are made of FR4 epoxy resin board with a dielectric constant of 4.4, a loss tangent Tanδ of 0.02, and a copper cladding thickness of 0.035mm. The lower PCB oscillator radiating surface (5) is a double-sided copper clad board with a thickness of 1mm, and the upper PCB oscillator radiating surface (4) is a single-sided copper clad board with a thickness of 0.6mm. Its copper foil is printed on the side facing the lower PCB oscillator radiating surface (5). The lower PCB oscillator radiating surface (5) is connected to the positive and negative copper surfaces through metallized vias (7). The upper PCB oscillator radiating surface (4) and the lower PCB oscillator radiating surface (5) are connected by electromagnetic coupling to extend the frequency band. When the lower PCB oscillator radiating surface (5) works independently, it covers the 1.7GHz–2.7GHz frequency band. After the upper PCB oscillator radiating surface (4) is superimposed, the working frequency band of the radiating unit is extended to 1.4GHz–2.7GHz.

2. The broadband extended parasitic layer dual-polarized base station antenna radiating element according to claim 1, characterized in that, The lower PCB oscillator radiation surface (5) includes a front copper foil surface (6), a metallized via (7), a PCB board (8), and a back copper foil surface (9). The front copper foil surface (6) and the back copper foil surface (9) have a four-leaf symmetrical structure, and four radial arms extend out along the ±45° direction. The ends of the radial arms are provided with a tooth-like structure. Each radiating arm is provided with several metallized vias (7), the inner wall of which is covered with copper to connect the front copper foil surface (6) and the back copper foil surface (9). Each radiating arm has a flat, oval-shaped hollow groove inside, from which a thin, straight branch extends.

3. The broadband extended parasitic layer dual-polarized base station antenna radiating element according to claim 2, characterized in that, The diameter of the metallized via (7) is 1.2 mm–3 mm; The PCB board (8) is square with a side length of 1.15λ1-1.3λ1, where λ1 is the wavelength corresponding to the lowest frequency.

4. The broadband extended parasitic layer dual-polarized base station antenna radiating element according to claim 1, characterized in that, The upper PCB oscillator radiation surface (4) includes a PCB board (10) and a reverse copper foil surface (11). The reverse copper foil surface (11) is a single-sided copper-clad surface facing the radiating surface (5) of the lower PCB oscillator; The side length of the PCB board (10) is the same as that of the PCB board (8); The reverse copper foil surface (11) includes four sets of symmetrically distributed inner and outer arcs and quasi-square structures at the four corners. The widths of the inner and outer arcs are 0.6mm-1.5mm and 1mm-2mm, respectively, and the arc angles are 16-19°. The quasi-square structure has a circular hollow inside.

5. The broadband extended parasitic layer dual-polarized base station antenna radiating element according to claim 1, characterized in that, The support columns (16, 17) of the zinc alloy metal support (2) pass through the lower PCB board (8) and are welded to the radiating arm.

6. The broadband extended parasitic layer dual-polarized base station antenna radiating element according to claim 1, characterized in that, The radiation unit consists of two mutually perpendicular dipoles. Each dipole consists of a pair of diagonally oriented metal microstrip line radiation arms and corresponding metallized vias (7), corresponding to two polarization directions of ±45° respectively.

7. A method for assembling a broadband extended parasitic layer dual-polarized base station antenna radiating element, characterized in that, The method includes: Place the reflector (1) horizontally and fix the zinc alloy metal support (2) to the center of the reflector (1) with screws, ensuring that the wire hole of the zinc alloy metal support (2) faces the PCB. Align the lower PCB oscillator radiation surface (5) with the support column (16, 17) of the zinc alloy metal support (2) and pass through and fix it so that the support column (16, 17) is welded and fixed to the radiation arm of the lower PCB oscillator radiation surface (5). The upper PCB oscillator radiation surface (4) is placed parallel to the lower PCB oscillator radiation surface (5) with the copper foil facing the lower PCB oscillator radiation surface (5) and aligned with the center. The spacing is fixed by using an insulating medium. Two coaxial feed wires (3) with a characteristic impedance of 50Ω are passed through the wire holes at the bottom of the zinc alloy metal support (2). Their outer conductors are welded to the bottom of the zinc alloy metal support (2), and their inner conductors are welded to the feed point at the end of the corresponding radiating arm of the lower PCB oscillator radiation surface (5) after passing through the support column (16, 17). The assembled radiating unit is debugged until the voltage standing wave ratio is less than 1.45 in the 1.4GHz–2.7GHz frequency band, and the assembly is completed.

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