Iron tower wave-absorbing net structure for installing 5g antenna and geometric dimension determination method

Abstract

The present application relates to a kind of tower wave-absorbing net structure for installing 5G antenna and geometric dimension determination method, belong to communication base station technical field, wave-absorbing net structure is set on the tower in the back of antenna, wave-absorbing net structure includes the metal net of multiple layers from top to bottom staggered arrangement, metal net is square structure, the mesh of metal net is square, electromagnetic wave of antenna radiation is absorbed by eddy current, reduce the scattering of electromagnetic wave to tower.

Description

Technical Field

[0001] This invention relates to the field of communication base station technology, and in particular to a tower absorbing mesh structure and a method for determining its geometric dimensions for installing 5G antennas. Background Technology

[0002] As mobile communication networks increasingly demand higher capacity and coverage, the number of communication base stations is also growing. Therefore, "shared towers," which add communication base station functionality to existing high-voltage transmission line towers, are becoming a new resource-sharing model.

[0003] The open sharing of power towers and communication towers is a huge boon for promoting the coordinated development of power and communication infrastructure, especially for the upcoming deployment of 5G networks, offering multiple benefits: First, using the densely distributed power towers along urban and rural areas and highways and railways for communication construction can promote wider and faster coverage of telecommunications networks, greatly shorten the construction cycle, improve the efficiency of communication base station construction, reduce the construction cost of communication base stations, and strongly support the implementation of the "Network Power" strategy, supporting the deep coverage of 4G networks and the rapid deployment of 5G networks; Second, promoting the formation of a market-oriented co-construction and sharing cooperation model between power and communication companies can help power grid companies revitalize resources and improve efficiency, which is conducive to the preservation and appreciation of state-owned assets and the amplification of their functions; Third, it effectively reduces the land resources occupied by newly added communication tower base stations and their environmental impact, becoming a model for practicing the national green development and coordinated development concepts.

[0004] Antennas, as an indispensable module in mobile communication systems, primarily function to radiate and receive electromagnetic waves. Mechanical antennas refer to mobile antennas whose downtilt angle is mechanically adjusted. Mechanical tilting means the antenna physically rotates around an axis, thus altering the shape and orientation of its radiation pattern. During adjustment, although the coverage distance along the main lobe changes significantly, the amplitudes of the vertical and horizontal components remain constant, making the antenna pattern prone to distortion. Practice has shown that the optimal downtilt angle for a mechanical antenna is 1°–5°. If the adjustment angle is too large, the antenna pattern shape changes drastically, transforming from a pear shape (without downtilt) to a spindle shape. Mechanical antennas are a common type of base station antenna. Because they cannot be used for large downtilt angles, they are generally used in rural and suburban areas with large coverage areas.

[0005] However, due to prolonged outdoor hanging, changes in the antenna's tilt angle are inevitable due to external forces such as wind, rain, and snow. When this happens, the electromagnetic waves radiated by the antenna will be scattered by the metal structure of the tower. The reflection and refraction of these electromagnetic waves by the tower's metal frame will affect the antenna's radiation field, resulting in an increase in irregular sidelobes in the antenna pattern and impacting communication quality. Current solutions involve expanding the range of the antenna's downtilt angle, but this increases the antenna's size, which is particularly difficult to modify for mature products. Summary of the Invention

[0006] The purpose of this invention is to provide a tower absorbing mesh structure and a method for determining its geometric dimensions for installing 5G antennas. The absorbing mesh structure installed on the tower behind the antenna absorbs the electromagnetic waves radiated by the antenna, thereby reducing the scattering of electromagnetic waves by the tower.

[0007] To achieve the above objectives, the present invention provides the following solution:

[0008] A tower absorbing mesh structure for installing a 5G antenna, the absorbing mesh structure is installed on the tower behind the antenna, the absorbing mesh structure includes: multiple layers of metal mesh arranged alternately from top to bottom;

[0009] The metal mesh has a square structure; the mesh openings of the metal mesh are square.

[0010] Optionally, the process for determining the side length of the metal mesh is as follows:

[0011] Obtain the maximum value between 20 times the wavelength corresponding to the minimum operating frequency of the antenna and 5 times the length of the antenna diagonal;

[0012] Determine whether the maximum value is greater than the cross-sectional side length of the tower at the antenna installation location, and obtain the determination result;

[0013] If the judgment result indicates yes, then the metal mesh is a rectangular structure, the shorter side of the rectangular structure is equal to the cross-sectional side length of the tower at the antenna installation location, and the longer side of the rectangular structure is equal to the maximum value.

[0014] If the judgment result indicates no, then the metal mesh is a square structure, and the side length of the square structure is equal to the maximum value.

[0015] Optionally, the side length of the mesh is

[0016] a=n·λ max

[0017] In the formula, a is the side length of the mesh, n is a coefficient, and λ is a constant. max This is the wavelength corresponding to the antenna's maximum operating frequency.

[0018] Optionally, the number of layers of the metal mesh is:

[0019]

[0020] In the formula, N is the number of layers, β is the maximum ratio of the maximum value of the scattered field to the maximum value of the transmitted field, θ is the maximum tilt angle of the antenna, λ is the wavelength corresponding to the antenna operating frequency, πθ is the ratio of the maximum scattered field to the transmitted field after the antenna is tilted, a is the side length of the mesh, and ceil() is the round-up function.

[0021] Optionally, the metal mesh is an iron wire with a relative magnetic permeability greater than or equal to 600, and the radius of the iron wire is in the range of 0.1±0.02mm.

[0022] Optionally, the surface of the metal mesh is coated with an insulating material, the thickness of which is less than or equal to 0.02 mm.

[0023] A method for determining the geometric dimensions of a tower absorbing mesh structure for mounting 5G antennas, the method being applied to the aforementioned tower absorbing mesh structure for mounting 5G antennas, the method comprising:

[0024] The side length of the metal mesh of the absorbing mesh structure is determined based on the minimum operating frequency of the antenna.

[0025] The mesh size of the metal mesh in the absorbing mesh structure is determined based on the maximum operating frequency of the antenna.

[0026] Based on the mesh side length, and according to the principle that the maximum value of the scattered field does not exceed the maximum value of the emitted field as controlled by β, the number of metal mesh layers in the absorbing mesh structure is determined.

[0027] Optionally, determining the side length of the metal mesh of the absorbing mesh structure based on the minimum operating frequency of the antenna specifically includes:

[0028] Obtain the maximum value between 20 times the wavelength corresponding to the minimum operating frequency of the antenna and 5 times the length of the antenna diagonal;

[0029] Determine whether the maximum value is greater than the cross-sectional side length of the tower at the antenna installation location, and obtain the determination result;

[0030] If the judgment result indicates yes, then the metal mesh is a rectangular structure, the shorter side of the rectangular structure is equal to the cross-sectional side length of the tower at the antenna installation location, and the longer side of the rectangular structure is equal to the maximum value.

[0031] If the judgment result indicates no, then the metal mesh is a square structure, and the side length of the square structure is equal to the maximum value.

[0032] Optionally, determining the mesh side length of the metal mesh of the absorbing mesh structure based on the maximum operating frequency of the antenna specifically includes:

[0033] Based on the antenna's maximum operating frequency, use the formula a = n·λ max Determine the side length of the mesh openings of the metal mesh in the absorbing mesh structure;

[0034] In the formula, a is the side length of the mesh, n is a coefficient, and λ is a constant. max This is the wavelength corresponding to the antenna's maximum operating frequency.

[0035] Optionally, based on the mesh side length and according to the principle that the maximum value of the scattered field does not exceed the maximum value of the emitted field as controlled by β, the number of layers of the metal mesh in the absorbing mesh structure is determined, specifically including:

[0036] Based on the mesh side length, and adhering to the principle that the maximum value of the scattered field does not exceed the maximum value of the emitted field as controlled by β, the formula is used... Determine the number of layers of the metal mesh in the microwave absorbing mesh structure;

[0037] In the formula, N is the number of layers, β is the maximum ratio of the maximum value of the scattered field to the maximum value of the transmitted field, θ is the maximum tilt angle of the antenna, λ is the wavelength corresponding to the antenna operating frequency, πθ is the ratio of the maximum scattered field to the transmitted field after the antenna is tilted, a is the side length of the mesh, and ceil() is the round-up function.

[0038] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0039] This invention discloses a tower absorbing mesh structure and a method for determining its geometric dimensions for installing 5G antennas. The absorbing mesh structure is installed on the tower behind the antenna and includes multiple layers of staggered metal mesh. The metal mesh has a square structure and square mesh openings. Eddy currents are used to absorb the electromagnetic waves radiated by the antenna, thereby reducing the scattering of electromagnetic waves by the tower. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 A top view of the metal mesh provided by the present invention;

[0042] Figure 2 This is a top view of the microwave absorbing mesh structure provided by the present invention;

[0043] Figure 3 A flowchart illustrating the method for determining the geometric dimensions of a tower absorbing mesh structure for installing a 5G antenna, as provided by the present invention. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] The purpose of this invention is to provide a tower absorbing mesh structure and a method for determining its geometric dimensions for installing 5G antennas. The absorbing mesh structure installed on the tower behind the antenna absorbs the electromagnetic waves radiated by the antenna, thereby reducing the scattering of electromagnetic waves by the tower.

[0046] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0047] This invention provides a tower absorbing mesh structure for mounting 5G antennas, such as... Figure 1-2 As shown, the absorbing mesh structure is installed on the iron tower behind the antenna. The absorbing mesh structure includes multiple layers of metal mesh arranged alternately from top to bottom.

[0048] The metal mesh has a square structure; the mesh openings are square.

[0049] To reduce the scattering of electromagnetic waves by the tower, the wave-absorbing mesh structure designed in this invention is a multi-layered mesh structure, which is fixed to the outside of the tower behind the antenna to achieve the absorption of electromagnetic waves.

[0050] The process for determining the side length of the metal mesh is as follows:

[0051] Obtain the maximum value between 20 times the wavelength corresponding to the minimum operating frequency of the antenna and 5 times the length of the antenna diagonal;

[0052] Determine whether the maximum value is greater than the side length of the cross section of the tower at the antenna installation location, and obtain the determination result;

[0053] If the judgment result indicates yes, then the metal mesh is a rectangular structure, the short side length c of the rectangular structure is equal to the cross-sectional side length of the tower at the antenna installation location, and the long side length b of the rectangular structure is equal to the maximum value.

[0054] If the judgment result is negative, then the metal mesh is a square structure, and the side length of the square structure is equal to the maximum value.

[0055] The side length of the mesh openings in the metal mesh is a = n·λ max In the formula, a is the side length of the mesh, n is a coefficient, and λ is a constant. max This represents the wavelength corresponding to the antenna's maximum operating frequency. Considering wind resistance, the side length of each mesh opening is no less than 0.5m, and the electrical connections between all mesh openings are secure.

[0056] The number of layers in the metal mesh is In the formula, N is the number of layers, β is the maximum ratio of the maximum value of the scattered field to the maximum value of the transmitted field, θ is the maximum tilt angle of the antenna, λ is the wavelength corresponding to the antenna operating frequency, πθ is the ratio of the maximum scattered field to the transmitted field after the antenna is tilted, a is the side length of the mesh, and ceil() is the round-up function.

[0057] The minimum number of metal mesh layers is controlled according to the following rules:

[0058] (1) The absorption of a single layer accounts for a significant portion of the incident field strength.

[0059] (2) The ratio of the maximum scattered field to the transmitted field after the antenna is tilted is πtanθ, which can be approximated as πθ (tilt angle is less than 15°);

[0060] (3) The number of layers is controlled by β, which is the proportion of the maximum value of the scattered field not exceeding the maximum value of the emitted field, that is, the side lobe influence does not exceed β of the main lobe.

[0061] The metal mesh is made of iron wire with a relative magnetic permeability greater than or equal to 600, and the radius of the iron wire is in the range of 0.1±0.02mm.

[0062] The surface of the metal mesh is coated with an insulating material, the thickness of which is less than or equal to 0.02 mm, so that each layer is electrically insulated.

[0063] This invention comprises two aspects:

[0064] 1. Absorbing Material Design: The absorbing material structure uses ferromagnetic materials with different mesh structures as the framework. Different mesh sizes are designed according to the antenna's operating frequency, utilizing eddy currents to absorb electromagnetic waves. An insulating material is coated on the outside of the ferromagnetic material to achieve insulation between different layers of ferromagnetic material.

[0065] 2. Arrangement of absorbing materials: In order to achieve full coverage, 5G antennas are arranged around the tower. Therefore, in order to reduce the impact of the installation of absorbing materials on the tower's balance, absorbing materials are installed at the four corners of the tower to absorb electromagnetic waves while ensuring the mechanical balance of the structure.

[0066] This invention also provides a method for determining the geometric dimensions of a tower absorbing mesh structure for installing 5G antennas, such as... Figure 3 As shown, the determination method is applied to the aforementioned tower absorbing mesh structure used for installing 5G antennas, and the method includes:

[0067] Step 101: Determine the side length of the metal mesh of the absorbing mesh structure based on the minimum operating frequency of the antenna.

[0068] Specifically, it includes:

[0069] Obtain the maximum value between 20 times the wavelength corresponding to the minimum operating frequency of the antenna and 5 times the length of the antenna diagonal;

[0070] Determine whether the maximum value is greater than the side length of the cross section of the tower at the antenna installation location, and obtain the determination result;

[0071] If the judgment result indicates yes, then the metal mesh is a rectangular structure, the length of the shorter side of the rectangular structure is equal to the length of the cross section of the tower at the antenna installation location, and the length of the longer side of the rectangular structure is equal to the maximum value.

[0072] If the judgment result is negative, then the metal mesh is a square structure, and the side length of the square structure is equal to the maximum value.

[0073] Step 102: Determine the mesh side length of the metal mesh of the absorbing mesh structure based on the maximum operating frequency of the antenna.

[0074] Specifically, it includes:

[0075] Based on the antenna's maximum operating frequency, use the formula a = n·λ max The side length of the mesh openings in the metal mesh structure of the absorbing mesh is determined by the formula; where a is the side length of the mesh opening, n is a coefficient, and λ is the side length of the mesh opening. max This is the wavelength corresponding to the antenna's maximum operating frequency.

[0076] Step 103: Based on the mesh side length, and following the principle that the maximum value of the scattered field does not exceed the maximum value of the emitted field as controlled by β, determine the number of metal mesh layers in the absorbing mesh structure.

[0077] Specifically, it includes:

[0078] Based on the mesh side length, and following the principle that the maximum value of the scattered field does not exceed the maximum value of the emitted field as controlled by β, the formula is used... Determine the number of layers in the metal mesh of the absorbing mesh structure; where N is the number of layers, β is the maximum proportion of the maximum value of the scattered field to the maximum value of the transmitted field, θ is the maximum tilt angle of the antenna, λ is the wavelength corresponding to the antenna operating frequency, πθ is the proportion of the maximum scattered field to the transmitted field after the antenna is tilted, a is the side length of the mesh, and ceil() is the round-up function.

[0079] Following the method described above, if the antenna operates at 3.5 GHz, with a wavelength of approximately 8.56 cm, then the side length of the mesh opening should be 0.5 m. In this case, the diagonal length of the antenna is generally greater than 20 times the mesh opening size. Therefore, the metal mesh area can be 5 m × 5 m, fixed to a tower behind the antenna, with the antenna positioned in front of the center of the metal mesh.

[0080] Considering the influence of external environmental forces, the maximum tilt angle of the antenna can reach 10° (0.1745 radians). The absorption effect of a single-layer metal mesh is 5%.

[0081] Two layers of metal mesh are required to control the sidelobe field strength to not exceed 2% of the main lobe field strength.

[0082] This invention is based on the idea that electromagnetic waves will not be strongly scattered when the antenna tilt angle changes, and proposes a wave-absorbing material. Considering the limited number of operating frequencies for antennas (taking 5G antennas as an example, mainly operating in the 2.6GHz, 3.5GHz, and 4.9GHz bands), the wave-absorbing material structure is designed according to these operating frequencies. Furthermore, considering that the wave-absorbing material needs to be installed on the tower, a lightweight and breathable structure is chosen, taking into account the suspension weight and wind resistance, thus reducing the tower's scattering of electromagnetic waves.

[0083] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0084] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A tower absorbing mesh structure for mounting 5G antennas, characterized in that, The absorbing mesh structure is installed on the iron tower behind the antenna, and the absorbing mesh structure includes: multiple layers of metal mesh arranged alternately from top to bottom; The metal mesh has a square structure; the mesh openings of the metal mesh are square. The process for determining the side length of the metal mesh is as follows: Obtain the maximum value between 20 times the wavelength corresponding to the minimum operating frequency of the antenna and 5 times the length of the antenna diagonal; Determine whether the maximum value is greater than the cross-sectional side length of the tower at the antenna installation location, and obtain the determination result; If the judgment result indicates yes, then the metal mesh is a rectangular structure, the shorter side of the rectangular structure is equal to the cross-sectional side length of the tower at the antenna installation location, and the longer side of the rectangular structure is equal to the maximum value. If the judgment result indicates no, then the metal mesh is a square structure, and the side length of the square structure is equal to the maximum value.

2. The tower absorbing mesh structure for installing 5G antennas according to claim 1, characterized in that, The side length of the mesh is In the formula, a Let be the side length of the mesh. n For coefficients, This is the wavelength corresponding to the antenna's maximum operating frequency.

3. The tower absorbing mesh structure for installing a 5G antenna according to claim 1, characterized in that, The number of layers of the metal mesh is In the formula, N For the number of floors, β This represents the maximum proportion of the maximum value of the scattered field to the maximum value of the emitted field. θ This is the maximum tilt angle of the antenna. The wavelength corresponding to the antenna's operating frequency. This represents the proportion of the maximum scattered field to the transmitted field after the antenna is tilted. a Let be the side length of the mesh. This is the floor function.

4. The tower absorbing mesh structure for installing a 5G antenna according to claim 1, characterized in that, The metal mesh is made of iron wire with a relative magnetic permeability greater than or equal to 600, and the radius of the iron wire is in the range of 0.1±0.02mm.

5. The tower absorbing mesh structure for installing a 5G antenna according to claim 1, characterized in that, The surface of the metal mesh is coated with an insulating material, the thickness of which is less than or equal to 0.02 mm.

6. A method for determining the geometric dimensions of a tower absorbing mesh structure for installing 5G antennas, characterized in that, The determination method is applied to the tower absorbing mesh structure for installing 5G antennas as described in any one of claims 1-5, and the method includes: The side length of the metal mesh of the absorbing mesh structure is determined based on the minimum operating frequency of the antenna. The mesh size of the metal mesh in the absorbing mesh structure is determined based on the maximum operating frequency of the antenna. Based on the mesh side length, the proportion where the maximum value of the scattered field does not exceed the maximum value of the emitted field is... β The principle of control determines the number of layers of the metal mesh in the microwave absorbing mesh structure.

7. The method for determining the geometric dimensions of the tower absorbing mesh structure for installing 5G antennas according to claim 6, characterized in that, The step of determining the mesh side length of the metal mesh in the absorbing mesh structure based on the maximum operating frequency of the antenna specifically includes: Based on the antenna's maximum operating frequency, using the formula Determine the side length of the mesh openings of the metal mesh in the absorbing mesh structure; In the formula, a Let be the side length of the mesh. n For coefficients, This is the wavelength corresponding to the antenna's maximum operating frequency.

8. The method for determining the geometric dimensions of the tower absorbing mesh structure for installing 5G antennas according to claim 6, characterized in that, Based on the mesh side length, the proportion where the maximum value of the scattered field does not exceed the maximum value of the emitted field is... β The control principle determines the number of layers of the metal mesh in the microwave absorbing mesh structure, specifically including: Based on the mesh side length, the proportion where the maximum value of the scattered field does not exceed the maximum value of the emitted field is... β The principle of control, using formulas Determine the number of layers of the metal mesh in the microwave absorbing mesh structure; In the formula, N For the number of floors, β This represents the maximum proportion of the maximum value of the scattered field to the maximum value of the emitted field. θ This is the maximum tilt angle of the antenna. The wavelength corresponding to the antenna's operating frequency. This represents the proportion of the maximum scattered field to the transmitted field after the antenna is tilted. a Let be the side length of the mesh. This is the floor function.

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