Metamaterial structure and method for enhancing base station antenna signals

Abstract

The application is suitable for the technical field of base station antenna, and provides a metamaterial structure and method for enhancing base station antenna signals.The metamaterial structure comprises a plurality of unit metal structures, each unit metal structure comprising a metal outer frame and an internal metal arm, a uniform gap being present between the metal outer frame and the internal metal arm, the metal outer frame being equivalent to an inductor, the uniform gap forming a distributed capacitor, the metal outer frame, the internal metal arm and the uniform gap together constituting an LC resonance loop for adjusting electromagnetic response, the electromagnetic response characteristics of the metamaterial structure being able to be adjusted through the LC resonance loop, so that the overall impedance matching relationship between the base station antenna, the metamaterial structure itself and the actual deployment environment is effectively adjusted, and the adaptive condition of the beam is realized, and finally the technical problems of impedance mismatching and lack of beam control capability are solved, and the enhancement effect of the base station antenna signal is improved.

Description

Technical Field

[0001] This application belongs to the field of base station antenna technology, and in particular relates to a metamaterial structure and method for enhancing base station antenna signals. Background Technology

[0002] With the rapid development of mobile communication technology, especially the widespread deployment of 5G mobile communication networks, the coverage capability, signal transmission quality, and data transmission rate of base station antennas have become core elements for measuring the overall performance of communication systems. In actual network operation environments, the radiation performance of base station antennas faces multiple challenges. On the one hand, the impedance matching problem between the antenna system and free space is particularly prominent in broadband operation, making it difficult to achieve an ideal matching state across the entire operating frequency band. This results in some electromagnetic wave energy being reflected back to the signal source, causing significant energy loss and signal strength attenuation. On the other hand, the geometric characteristics of the antenna radiation beam, including beamwidth, directivity, and sidelobe suppression capability, typically have fixed patterns or limited adjustable ranges. They cannot be adaptively optimized according to dynamically changing propagation environments (such as high-rise building obstruction in densely populated urban areas, multipath effects caused by complex terrain, or fluctuations in user distribution), thus leading to problems such as coverage blind spots, increased signal interference, and unstable communication quality.

[0003] Traditional techniques primarily improve signal coverage by increasing transmit power, introducing active antenna arrays, or employing mechanical downtilt adjustment mechanisms. However, simply increasing transmit power not only significantly increases energy consumption but also leads to serious thermal management issues and increases system maintenance costs. While active antenna arrays can provide a certain degree of beamforming capability, their hardware structure is complex, manufacturing costs are high, and they are highly dependent on signal processing algorithms. Mechanical adjustment methods are limited by the precision and response speed of the physical structure, making it difficult to achieve fine-grained, real-time control of beam shape, especially in rapidly changing communication scenarios.

[0004] In recent years, metamaterial structures, as artificially designed electromagnetic structures, have attracted widespread attention in the field of antenna performance enhancement due to their unique electromagnetic response characteristics that cannot be achieved by natural materials.

[0005] However, current solutions for applying metamaterial structures to base station antennas generally have limitations: most designs optimize only a single performance parameter, such as unilaterally pursuing gain improvement or bandwidth expansion, while ignoring the overall impedance matching relationship between the base station antenna, the metamaterial structure itself, and the actual deployment environment. When this matching relationship is unbalanced, the metamaterial structure not only fails to effectively improve signal transmission but also introduces additional reflection loss, partially or even completely negating its expected performance gain. Furthermore, existing technologies lack a comprehensive solution that can simultaneously coordinate impedance matching optimization and dynamic beamforming adjustment, making it difficult to address the complex and ever-changing coverage requirements and environmental adaptability challenges of modern communication networks.

[0006] As can be seen from the above, the existing technology of using metamaterial structures to enhance base station antenna signals has the disadvantages of impedance mismatch and lack of beam control capability, resulting in poor enhancement effect of base station antenna signals. Summary of the Invention

[0007] In view of this, embodiments of this application provide a metamaterial structure and method for enhancing base station antenna signals, in order to solve the technical problem of poor enhancement effect of base station antenna signals in the prior art.

[0008] In a first aspect, embodiments of this application provide a metamaterial structure for enhancing base station antenna signals, comprising multiple unit metal structures, each unit metal structure comprising a metal outer frame and an inner metal arm, wherein there is a uniform gap between the metal outer frame and the inner metal arm, the metal outer frame is equivalent to an inductor, the uniform gap forms a distributed capacitance, and the metal outer frame, the inner metal arm and the uniform gap together constitute an LC resonant circuit for adjusting electromagnetic response.

[0009] Optionally, the shape of the metal outer frame is determined according to the operating frequency of the base station antenna, the type of the base station antenna, and the angle of the electromagnetic waves emitted by the base station antenna.

[0010] Optionally, the shape of the inner metal arm is a centrally symmetrical figure with an internal cross structure, and there are rectangular hollow areas in each of the four quadrants corresponding to the cross structure of the inner metal arm that are connected to the uniform gap.

[0011] Optionally, the parameters of the uniform gap, and / or the parameters of the rectangular hollow area, and / or the parameters of the cross structure are determined based on the target equivalent capacitance distribution of the metamaterial structure.

[0012] Optionally, the parameters of the uniform gap include the width of the uniform gap; the parameters of the rectangular cutout area include the size of the rectangular cutout area; and the parameters of the cross structure include the width and shape of the four ends of the cross structure.

[0013] Optionally, the unit metal structure includes a first metal structure; the metamaterial structure further includes a first flexible dielectric film, a first adhesive layer, and a dielectric layer, wherein a plurality of the first metal structures are disposed on the first flexible dielectric film, the first adhesive layer is disposed in the direction away from the first metal structure of the first flexible dielectric film, and the dielectric layer is disposed in the direction away from the first metal structure of the first adhesive layer.

[0014] Optionally, the unit metal structure further includes a second metal structure; the metamaterial structure further includes a second flexible dielectric film and a second adhesive layer, the second adhesive layer being disposed in the direction away from the first metal structure of the dielectric layer, the second flexible dielectric film being disposed in the direction away from the first metal structure of the second adhesive layer, and a plurality of second metal structures being disposed in the direction away from the first metal structure of the second flexible dielectric film.

[0015] Optionally, the dielectric constants of the first flexible dielectric film, the first adhesive layer, the dielectric layer, the second flexible dielectric film, and the second adhesive layer are determined based on the dielectric constant of the metamaterial structure, and the dielectric constant of the metamaterial structure is determined based on the operating frequency band of the metamaterial structure.

[0016] Optionally, the thicknesses of the first flexible dielectric film, the first adhesive layer, the dielectric layer, the second flexible dielectric film, and the second adhesive layer are each determined according to the dielectric constant of the metamaterial structure, and the dielectric constant of the metamaterial structure is determined according to the operating frequency band of the metamaterial structure.

[0017] Secondly, embodiments of this application provide a method for enhancing base station antenna signals, applied to a metamaterial structure as described in any of the first aspects, the method comprising: The target distance between the metamaterial structure and the base station antenna is determined based on the operating frequency of the base station antenna. Based on the target distance, the metamaterial structure is positioned in the electromagnetic wave propagation direction of the base station antenna.

[0018] The metamaterial structure and method for enhancing base station antenna signals provided in this application have the following beneficial effects: The metamaterial structure provided in this application includes multiple unit metal structures. Each unit metal structure includes a metal outer frame and an inner metal arm. There is a uniform gap between the metal outer frame and the inner metal arm. The metal outer frame is equivalent to an inductor, and the uniform gap forms a distributed capacitance. The metal outer frame, the inner metal arm, and the uniform gap together constitute an LC resonant circuit for adjusting the electromagnetic response. The electromagnetic response characteristics of the metamaterial structure can be adjusted through the LC resonant circuit, thereby effectively adjusting the overall impedance matching relationship between the base station antenna, the metamaterial structure itself, and the actual deployment environment, and realizing the adaptive conditions of the beam. Ultimately, it solves the technical problems of impedance mismatch and lack of beam control capability, and improves the signal enhancement effect of the base station antenna. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of a unit metal structure provided in an embodiment of this application; Figure 2 A schematic diagram of a unit metal structure provided in another embodiment of this application; Figure 3 This is a schematic diagram of a metamaterial structure provided in an embodiment of this application; Figure 4 A schematic diagram of a metamaterial structure provided in another embodiment of this application; Figure 5 This is a schematic diagram of the arrangement of a unit metal structure provided in an embodiment of this application; Figure 6 This is a schematic diagram of a metamaterial structure provided in an embodiment of this application; Figure 7 This is a schematic diagram of test data for a metamaterial structure provided in an embodiment of this application. Detailed Implementation

[0021] It should be noted that the terminology used in the embodiments of this application is only for explaining specific embodiments of this application and is not intended to limit this application. In the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more, "at least one" or "one or more" means one, two or more. The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0022] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0023] In base station antenna systems, the overall impedance matching between the antenna feed, metamaterial structure, and operating environment is neglected, leading to reflection loss during electromagnetic wave propagation. Impedance mismatch causes some signal energy to be reflected back to the source, resulting in a reduction in effective radiated power. At the same time, the beam shape adjustment range is limited by the fixed structure, making it difficult to dynamically optimize according to the propagation environment, thus affecting the continuity of signal coverage and the accuracy of directional control.

[0024] For example, in densely populated urban areas with high-rise buildings, the antennas deployed in 5G base stations cannot adaptively adjust their beams to avoid obstacles due to the shielding effect of buildings on electromagnetic waves, resulting in coverage blind spots in some areas. Furthermore, if the metamaterial structure is not fully matched with the feed source and the environment, the reflected signal is amplified, and the beamwidth and directivity parameters deviate from the design values, thereby creating signal interference areas and reducing the stability of the communication link.

[0025] If the aforementioned issues of impedance matching and beam adjustment coordination are not resolved, the radiation performance of base station antennas will continue to deteriorate, the coverage blind zone will expand, the signal interference intensity will increase, and ultimately the overall reliability of the communication system will decline.

[0026] To address the above issues, this application proposes a metamaterial structure for enhancing base station antenna signals. The metamaterial structure comprises multiple unit metal structures, each unit metal structure including a metal outer frame and an inner metal arm. A uniform gap exists between the metal outer frame and the inner metal arm. The metal outer frame is equivalent to an inductor, and the uniform gap forms a distributed capacitance. The metal outer frame, the inner metal arm, and the uniform gap together constitute an LC resonant circuit for regulating the electromagnetic response.

[0027] For ease of understanding, the following explains some key terms in this embodiment: Metamaterial structures refer to composite materials composed of artificially designed and manufactured subwavelength unit structures arranged periodically or aperiodically. These structures can exhibit extraordinary electromagnetic properties not found in naturally occurring materials, such as negative refractive index, negative permittivity, or negative permeability, thereby enabling flexible control of electromagnetic waves, including but not limited to absorption, reflection, transmission, polarization, phase, and amplitude.

[0028] Unitary metal structures are the basic building blocks of metamaterial structures. Each unitary metal structure typically has a specific geometry and size, and its electromagnetic properties determine the macroscopic electromagnetic response of the entire metamaterial structure. By designing unitary metal structures, precise control of incident electromagnetic waves can be achieved.

[0029] The metal frame is part of the unitary metal structure and is usually made of conductive material. Its geometry and size have a significant impact on the electromagnetic properties of the unitary metal structure. Under the influence of an electromagnetic field, the metal frame can be equivalent to an inductor, impeding changes in current.

[0030] The internal metal arm is another conductive component in the unitary metal structure, located inside the outer metal frame. This internal metal arm, together with the outer metal frame, creates a specific electromagnetic coupling effect, thereby influencing the overall electromagnetic response of the unitary metal structure.

[0031] A uniform gap refers to a spatial region with a relatively consistent width existing between the outer metal frame and the inner metal arm. This gap is typically filled with a dielectric material or air. Under the influence of an electromagnetic field, this uniform gap can form a distributed capacitance, which stores charge and impedes changes in voltage.

[0032] Inductance refers to the property of generating electromotive force in a circuit due to changes in current; its magnitude is measured by the inductance coefficient. In metamaterial structures, the geometry and dimensions of the metallic portion determine its equivalent inductance value, affecting the propagation characteristics of electromagnetic waves.

[0033] Distributed capacitance refers to a spatially dispersed capacitance effect, typically formed by a dielectric or air gap between two or more conductors. In metamaterial structures, the presence of uniform gaps allows charge to accumulate between metallic structures, thus forming distributed capacitance and affecting the phase and amplitude of electromagnetic waves.

[0034] An LC resonant circuit is a circuit composed of an inductor (L) and a capacitor (C). Resonance occurs when its operating frequency matches the circuit's inherent resonant frequency. In metamaterial structures, the equivalent inductance of the metal outer frame and the distributed capacitance formed by the uniform gap together constitute an LC resonant circuit. The resonant characteristics of this circuit determine the response of the unit metal structure to electromagnetic waves of a specific frequency.

[0035] Electromagnetic response refers to the characteristics exhibited by a material or structure under the influence of an electromagnetic field, including changes in the absorption, reflection, transmission, polarization, phase, and amplitude of electromagnetic waves.

[0036] This embodiment provides a metamaterial structure for enhancing base station antenna signals. Through its unique electromagnetic properties, this metamaterial structure can modulate the electromagnetic waves emitted by the base station antenna, thereby improving signal coverage and quality.

[0037] Specifically, the outer metal frame, the inner metal arm, and the uniform gap together constitute an LC resonant circuit for adjusting the electromagnetic response. In this unit metal structure, the equivalent inductance provided by the outer metal frame interacts with the distributed capacitance formed by the uniform gap to form an LC resonant circuit. When the frequency of the incident electromagnetic wave is close to the resonant frequency of this LC resonant circuit, electromagnetic waves outside the passband are absorbed, allowing only electromagnetic waves within a specific frequency range to pass. By precisely designing the geometric parameters of the outer metal frame, the inner metal arm, and the uniform gap, the resonant frequency and quality factor of the LC resonant circuit can be adjusted, thereby achieving effective control of electromagnetic waves at specific frequencies to enhance the base station antenna signal.

[0038] More specifically, the shape of the internal metal arm is a centrally symmetrical figure with an internal cross structure, and there are rectangular hollow areas connected to the uniform gaps in each of the four quadrants corresponding to the cross structure of the internal metal arm.

[0039] The aforementioned metamaterial structure, consisting of a metal outer frame, internal metal arms, and uniform gaps, forms an LC resonant circuit. Its electromagnetic response characteristics are influenced by the combined effects of these structural parameters. When the shape of the internal metal arms is designed as a centrally symmetrical cross-shaped structure, this cross structure can provide multi-directional current paths and electric field distributions, thereby forming more complex resonant modes within the unit metal structure. This design increases the degrees of freedom in the interaction between electromagnetic waves and the metamaterial structure, enabling the metamaterial structure to produce a more flexible response to incident electromagnetic waves.

[0040] Furthermore, rectangular hollow areas connected to the uniform gap are set in each of the four quadrants corresponding to the cross structure of the internal metal arm. These hollow areas, by changing the effective coupling area and electric field distribution between the internal metal arm and the uniform gap, are equivalent to introducing additional distributed capacitance or inductance effects into the LC resonant circuit. By precisely designing the size and position of these hollow areas, the equivalent capacitance and equivalent inductance of the LC resonant circuit can be finely adjusted, thereby achieving precise control over the resonant frequency, bandwidth, and quality factor. This structural combination enables the metamaterial structure not only to achieve basic electromagnetic response adjustment but also to provide more refined tuning capabilities while maintaining the compactness of the unit structure, in order to adapt to the complex signal enhancement requirements of base station antennas at different operating frequencies and electromagnetic wave angles.

[0041] The following are schematic diagrams of two unit metal structures.

[0042] Please see Figure 1 , Figure 1 Please refer to the structural schematic diagram of a unit metal structure provided in the embodiments of this application. Figure 1 The unit metal structure may include a metal outer frame and an inner metal arm, with a uniform gap between the metal outer frame and the inner metal arm. Figure 1 In the design, the outer metal frame is a centrally symmetrical polygon, specifically a regular hexagon. The inner metal arm is a centrally symmetrical cross-shaped figure, specifically, the four ends of the cross-shaped figure are polygons, and there are rectangular cutout areas connected to uniform gaps in the four quadrants corresponding to the cross-shaped figure of the inner metal arm.

[0043] Please see Figure 2 , Figure 2 For a structural schematic diagram of a unit metal structure provided in another embodiment of this application, please refer to [link / reference]. Figure 2 The unit metal structure may include a metal outer frame and an inner metal arm, with a uniform gap between the metal outer frame and the inner metal arm. Figure 2 In the design, the outer metal frame is circular, and the inner metal arm is a centrally symmetrical cross-shaped structure. Specifically, the four ends of the cross structure are arc-shaped, and there are rectangular hollow areas connected to uniform gaps in the four quadrants corresponding to the cross structure of the inner metal arm.

[0044] In practical applications, if the design of the metamaterial structure fails to fully consider the specific operating characteristics of the base station antenna it serves, it may lead to low electromagnetic coupling efficiency between the metamaterial structure and the base station antenna, thereby affecting the signal enhancement effect.

[0045] In this regard, this application further proposes that the shape of the metal outer frame is determined according to the operating frequency of the base station antenna, the type of base station antenna, and the angle of the electromagnetic waves emitted by the base station antenna.

[0046] The shape of the metal outer frame refers to the geometric form of the outer contour of the unit metal structure. This shape directly affects the equivalent inductance value of the metal outer frame, and thus determines the resonant frequency of the LC resonant circuit.

[0047] In practical applications, compared to metamaterial structures with centrally symmetrical polygonal metal outer frames, metamaterial structures with circular metal outer frames are less sensitive to the polarization direction of incident electromagnetic waves. Furthermore, for plane waves incident along any polarization direction, the projection of the electric field onto the pattern plane has the same current path length, which keeps the equivalent capacitance and equivalent inductance of the unit structure stable, thereby maintaining consistent antenna performance.

[0048] Based on the above, "the shape of the metal outer frame is determined according to the operating frequency of the base station antenna, the type of base station antenna, and the angle of the electromagnetic waves emitted by the base station antenna" can be specifically defined as follows: If the operating frequency of the base station antenna is greater than a preset frequency threshold, or the type of base station antenna is a circularly polarized antenna, or the angle of the electromagnetic waves emitted by the base station antenna is greater than a preset angle threshold, the shape of the metal outer frame can be determined to be circular (e.g., ...). Figure 2 (as shown), otherwise, the shape of the metal outer frame can be defined as a centrally symmetric polygon (such as...). Figure 1 (As shown) This application's solution achieves optimized matching of electromagnetic characteristics between the metamaterial structure and the base station antenna by closely integrating the shape design of the metal outer frame with the specific operating parameters of the base station antenna. Specifically, the shape of the metal outer frame is precisely designed to ensure that the LC resonant circuit it forms can generate the best electromagnetic response at the operating frequency of the base station antenna. Furthermore, considering the type of base station antenna and the angle of its emitted electromagnetic waves, the shape of the metal outer frame can be further optimized to maximize the coupling efficiency of the metamaterial structure for electromagnetic waves of a specific direction or polarization.

[0049] Through the aforementioned technical solutions, metamaterial structures can be customized to suit the specific operating frequency, type, and electromagnetic wave emission angle of base station antennas. This customized design ensures that the LC resonant circuit within the metamaterial structure achieves optimal electromagnetic coupling and energy transfer with the electromagnetic waves emitted by the base station antenna, thereby significantly improving the efficiency and effectiveness of signal enhancement. This allows metamaterial structures to more precisely serve specific base station antenna application scenarios, overcoming the potential mismatch issues of general-purpose metamaterial structures, and ultimately improving the coverage, signal quality, or data transmission rate of base station antennas.

[0050] In practical applications, to more precisely control the electromagnetic properties of metamaterial structures, especially their equivalent capacitance distribution, and achieve optimal signal enhancement, refined design of structural parameters is required. To this end, this application further proposes parameters for uniform gaps, and / or parameters for rectangular hollow regions, and / or parameters for cross-shaped structures, determined based on the target equivalent capacitance distribution of the metamaterial structure.

[0051] More specifically, the parameters for uniform gaps include the width of the uniform gaps; the parameters for rectangular cutout areas include the size of the rectangular cutout areas; and the parameters for cross structures include the width and shape of the four ends of the cross structure.

[0052] The width of the uniform gap refers to the lateral dimension of the gap formed between the outer metal frame and the inner metal arm. This width is one of the key geometric parameters affecting the distributed capacitance formed by the uniform gap. By adjusting this width, the value of the distributed capacitance can be changed, thereby affecting the resonant frequency and electromagnetic response characteristics of the LC resonant circuit.

[0053] The size of the rectangular cutout region refers to the geometric dimensions of the rectangular cutout region present in the four quadrants corresponding to the cross structure of the internal metal arm. This size is typically determined by the length and width of the rectangular cutout region, or characterized by its area. The presence of the rectangular cutout region alters the current path and effective length of the internal metal arm, thereby affecting the equivalent inductance and capacitance of the LC resonant circuit.

[0054] The width and shape of the four ends of the cross structure refer to the lateral dimensions of the outward extensions of the cross-shaped structure of the inner metal arms. The shape refers to the geometric contours of these ends, which can be rectangular, circular, conical, or other irregular shapes. These parameters directly affect the coupling strength between the cross structure and the uniform gap, as well as the current distribution within the inner metal arms. By adjusting the width and shape of the ends, the inductance and capacitance of the LC resonant circuit can be finely controlled, particularly significantly affecting the high-frequency response and bandwidth characteristics.

[0055] This application's solution, by explicitly defining the width of the uniform gap, the size of the rectangular hollow area, and the width and shape of the four ends of the cross structure, makes the control of key geometric parameters in the metamaterial structure concrete and operable. In the aforementioned metamaterial structure, the outer metal frame, the inner metal arms, and the uniform gap together constitute an LC resonant circuit for adjusting the electromagnetic response. The width of the uniform gap directly determines the value of the distributed capacitance, while the size of the rectangular hollow area and the width and shape of the four ends of the cross structure jointly affect the effective inductance of the inner metal arms and the coupling capacitance with the uniform gap. By precisely setting these specific geometric parameters, fine-tuning of the electromagnetic response characteristics of the LC resonant circuit, such as the resonant frequency, quality factor, and bandwidth, can be achieved.

[0056] In some implementations, although the metamaterial structure described above can form an LC resonant circuit through unit metal structures, metal outer frames, internal metal arms and uniform gaps, and can regulate electromagnetic response, a more refined physical implementation scheme is needed in order to integrate these resonant units into practical applications and ensure their structural stability, flexibility and reliability in complex environments.

[0057] In this regard, this application further proposes that the unit metal structure includes a first metal structure; the metamaterial structure also includes a first flexible dielectric film, a first adhesive layer and a dielectric layer, a plurality of first metal structures are disposed on the first flexible dielectric film, the first adhesive layer is disposed in the direction away from the first metal structure of the first flexible dielectric film, and the dielectric layer is disposed in the direction away from the first metal structure of the first adhesive layer.

[0058] Please see Figure 3 , Figure 3 This is a schematic diagram of a metamaterial structure provided in an embodiment of this application. Figure 3 As shown, the metamaterial structure includes multiple first metal structures, a first flexible dielectric film, a first adhesive layer, and a dielectric layer. The multiple first metal structures are disposed on the first flexible dielectric film, the first adhesive layer is disposed in the direction away from the first metal structures of the first flexible dielectric film, and the dielectric layer is disposed in the direction away from the first metal structures of the first adhesive layer.

[0059] The first metal structure is the basic resonant unit constituting the metamaterial. Its function is to form an LC resonant circuit through the outer metal frame, the inner metal arm, and the uniform gap, thereby achieving a specific response to electromagnetic waves. In the embodiments of this application, each of the first metal structures is arranged periodically on the first flexible dielectric film. More specifically, the periodic arrangement can be a rectangular grid arrangement.

[0060] The first flexible dielectric film, serving as the substrate supporting the first metallic structure, not only provides mechanical support but also endows the entire metamaterial structure with flexibility.

[0061] The first adhesive layer is used to firmly bond the first flexible dielectric film to the dielectric layer, ensuring the integrity and stability of the structure.

[0062] As part of the metamaterial structure, the dielectric layer provides additional mechanical support and dielectric environment, and its dielectric constant and thickness have a significant impact on the overall electromagnetic properties of the metamaterial.

[0063] Through the aforementioned technical solutions, the metamaterial structure achieves excellent structural stability and mechanical flexibility, enabling it to adapt to diverse mounting surfaces of base station antennas, including curved or irregular surfaces, thereby greatly expanding the application scenarios of metamaterials. Furthermore, this layered structure facilitates manufacturing and integration, and allows for precise control of the dielectric environment of the first metal structure, thereby optimizing the performance of the LC resonant circuit and ensuring that the metamaterial structure can efficiently and stably enhance the base station antenna signal.

[0064] In some embodiments described above in this application, a metamaterial structure is proposed, which enhances the base station antenna signal by placing a first metal structure on a first flexible dielectric film and sequentially stacking a first adhesive layer and a dielectric layer. However, a single-layer metal structure may have limitations in providing sufficiently strong electromagnetic response, widening the operating bandwidth, or achieving more flexible electromagnetic control, especially in applications requiring higher performance or more complex electromagnetic environments.

[0065] In this regard, this application further proposes that the aforementioned unit metal structure also includes a second metal structure; the aforementioned metamaterial structure also includes a second flexible dielectric film and a second adhesive layer, the second adhesive layer being disposed in the direction away from the first metal structure of the dielectric layer, the second flexible dielectric film being disposed in the direction away from the first metal structure of the second adhesive layer, and a plurality of second metal structures being disposed in the direction away from the first metal structure of the second flexible dielectric film.

[0066] Please see Figure 4 , Figure 4 This is a schematic diagram of a metamaterial structure provided for another embodiment of this application. Figure 4 The metamaterial structure shown is Figure 3 Compared to metamaterial structures, Figure 4 The metamaterial structure shown also includes a second metal structure, a second flexible dielectric film, and a second adhesive layer. The second adhesive layer is disposed in the direction away from the first metal structure of the dielectric layer, the second flexible dielectric film is disposed in the direction away from the first metal structure of the second adhesive layer, and multiple second metal structures are disposed in the direction away from the first metal structure of the second flexible dielectric film.

[0067] The second metallic structure refers to another set of metallic unit structures used for interaction with electromagnetic waves. These structures may have the same or different geometry, size, and materials as the first metallic structure, and their role is to provide additional electromagnetic response, thereby enhancing or optimizing the overall performance of the metamaterial structure.

[0068] The second flexible dielectric film is a flexible dielectric material layer used to support and carry the second metal structure.

[0069] The second adhesive layer is an adhesive layer used to firmly bond the second flexible dielectric film to the dielectric layer.

[0070] Multiple second metal structures are disposed in the direction away from the first metal structure of the second flexible dielectric film. This means that the second metal structures are arranged on the surface of the second flexible dielectric film and the surface is oriented away from the first metal structure, thereby forming the second active electromagnetic response layer of the metamaterial structure.

[0071] This application proposes a multilayer metamaterial structure by introducing a second metal structure, a second flexible dielectric film, and a second adhesive layer into an existing single-layer metamaterial structure, arranged in a specific stacking order. Specifically, a second adhesive layer and a second flexible dielectric film are sequentially placed below the dielectric layer, and multiple second metal structures are arranged on the second flexible dielectric film. This structural design allows the metamaterial structure to have two or more independent electromagnetic response layers. The first and second metal structures can be designed independently or collaboratively to achieve more complex and powerful electromagnetic wave manipulation capabilities. For example, they can be tuned to different resonant frequencies, thereby broadening the operating bandwidth of the metamaterial structure; or they can be designed to respond to electromagnetic waves with different polarization directions, thereby enhancing polarization diversity.

[0072] This multilayer stacking not only increases the interaction area and volume between metamaterials and electromagnetic waves, but also allows for precise control of the interlayer coupling strength and phase response by accurately controlling the thickness of the dielectric and adhesive layers between each layer. This significantly improves the enhancement efficiency and flexibility of metamaterial structures for base station antenna signals, effectively overcoming the performance limitations of single-layer structures.

[0073] In some embodiments described above, a metamaterial structure for enhancing base station antenna signals is proposed. This structure comprises multiple dielectric and adhesive layers, as well as a metal structure disposed on a flexible dielectric film. These layers collectively constitute the main body of the metamaterial structure. However, in practical applications, if the material parameters of these constituent layers are improperly selected, particularly if their dielectric constants fail to match the overall electromagnetic properties of the metamaterial structure and the operating frequency band of the base station antenna, the metamaterial structure may fail to effectively achieve its intended signal enhancement function, and may even introduce unnecessary losses or reflections, thereby affecting the overall performance of the base station antenna.

[0074] In this regard, this application further proposes that the dielectric constants of the first flexible dielectric film, the first adhesive layer, the dielectric layer, the second flexible dielectric film, and the second adhesive layer are determined based on the dielectric constant of the metamaterial structure, and the dielectric constant of the metamaterial structure is determined based on the operating frequency band of the metamaterial structure.

[0075] The dielectric constant is a physical quantity that measures the ability of a material to store electrical energy in an electric field. It directly affects the propagation speed and wavelength of electromagnetic waves in the material, as well as the impedance characteristics of the material.

[0076] The dielectric constant of a metamaterial structure refers to the equivalent dielectric property exhibited by the entire metamaterial on a macroscopic scale. To enable a metamaterial structure to achieve specific electromagnetic functions, such as a specific resonant frequency, impedance matching, or phase modulation, it needs to exhibit a specific equivalent dielectric constant. Therefore, during the design process, the required dielectric constants of each layer constituting the metamaterial structure (including the first flexible dielectric film, the first adhesive layer, the dielectric layer, the second flexible dielectric film, and the second adhesive layer) need to be derived in reverse from the equivalent dielectric constant of the target metamaterial structure.

[0077] The operating frequency band of a metamaterial structure refers to the frequency range within which it is designed to perform specific electromagnetic functions, such as the operating frequency of a base station antenna. Different operating frequency bands place different requirements on the electromagnetic response of metamaterial structures, which is directly reflected in their required equivalent dielectric constant. Therefore, the dielectric constant of a metamaterial structure needs to be precisely designed and optimized according to its expected operating frequency band to ensure optimal signal enhancement within the target frequency band.

[0078] This application's solution systematically determines the dielectric constants of each constituent layer in a metamaterial structure, ensuring that the entire metamaterial structure exhibits the expected electromagnetic response within a specific operating frequency band. Specifically, firstly, based on the operating frequency band of the base station antenna, the overall equivalent dielectric constant required by the metamaterial structure is determined to achieve functions such as precise resonant frequency matching, effective impedance control, or specific phase deflection of electromagnetic waves. Based on this, and according to the determined overall equivalent dielectric constant of the metamaterial structure, the individual layers constituting the metamaterial structure—namely, the first flexible dielectric film, the first adhesive layer, the dielectric layer, the second flexible dielectric film, and the second adhesive layer—are precisely selected or designed so that their respective dielectric constants can work synergistically to form the required overall electromagnetic environment. This layered and progressively determined method enables the LC resonant circuit formed by the unit metal structure in the metamaterial structure to efficiently couple with the external electromagnetic field and accurately resonate within the target operating frequency band, thereby effectively enhancing the base station antenna signal. In this way, the metamaterial structure can avoid performance degradation caused by material parameter mismatch, ensuring its stable and reliable operation in practical applications.

[0079] In some embodiments described above, a metamaterial structure for enhancing base station antenna signals is proposed. This structure comprises multiple layers of dielectric and metallic units, such as a first flexible dielectric film, a first adhesive layer, a dielectric layer, a second flexible dielectric film, and a second adhesive layer. The dielectric constants of these layers have been determined according to the operating frequency band of the metamaterial structure. However, in practical implementation, simply determining the dielectric constants of each layer may not be sufficient to precisely control the electromagnetic response of the entire metamaterial structure, as the physical thickness of each layer is also a key factor affecting electromagnetic wave propagation characteristics and the overall performance of the structure. If the thickness of these layers cannot be precisely set, the metamaterial structure may fail to achieve the expected signal enhancement effect within the target operating frequency band, or it may be difficult to guarantee performance consistency during manufacturing.

[0080] To address the aforementioned issues, this application further proposes that the dielectric constants of the first flexible dielectric film, the first adhesive layer, the dielectric layer, the second flexible dielectric film, and the second adhesive layer are determined based on the dielectric constant of the metamaterial structure, and the dielectric constant of the metamaterial structure is determined based on the operating frequency band of the metamaterial structure.

[0081] Thickness, as a crucial geometric parameter of the dielectric layer, along with the dielectric constant, determines the propagation speed, wavelength, and impedance characteristics of electromagnetic waves within the medium. Precisely determining the thickness of each layer ensures that the metamaterial structure achieves the required phase delay, energy coupling, and impedance matching within the target operating frequency band.

[0082] The above technical solution precisely determines the thicknesses of the first flexible dielectric film, the first adhesive layer, the dielectric layer, the second flexible dielectric film, and the second adhesive layer. These thicknesses are determined based on the dielectric constant and operating frequency band of the metamaterial structure. This refined thickness design, combined with the dielectric constant, enables more precise electromagnetic wave manipulation within the multilayer dielectric environment of the metamaterial structure.

[0083] The following example will provide a more detailed explanation of the above technical solution: Imagine a city environment where a base station antenna needs to provide stable 5G signal coverage to a specific area. This area is obstructed by tall buildings, causing severe signal attenuation in some directions and creating coverage blind spots. Furthermore, due to the complex environment, the impedance matching between the antenna and free space is not ideal, resulting in some signal energy loss. To address these issues, this embodiment provides a metamaterial structure deployed near the base station antenna to enhance the signal.

[0084] First, this metamaterial structure was designed to consist of multiple unit metal structures; please refer to [link / reference]. Figure 5 , Figure 5 This is a schematic diagram of the arrangement of a unit metal structure provided in an embodiment of this application, such as... Figure 5As shown, these unit metal structures are uniformly arranged on a flexible substrate to form a planar array. This multi-unit structure ensures that the metamaterial can effectively interact with the electromagnetic waves emitted by the base station antenna on a macroscopic scale, covering a large spatial range.

[0085] Each unit metal structure includes a metal outer frame and an inner metal arm. For example, the metal outer frame can be a square ring formed of copper on a dielectric substrate. The inner metal arm can be a cross-shaped structure located inside the square ring, also made of copper. This design allows each unit to have a clearly defined conductive path and charge accumulation area.

[0086] Between the outer metal frame and the inner metal arm, there exists a uniform gap. For example, the width of this gap can be precisely controlled within tens of micrometers and filled with air or a low-loss dielectric material. The presence of this uniform gap is key to the formation of distributed capacitance, which allows charge to be stored between the outer metal frame and the inner metal arm, thereby generating a capacitive effect under the influence of electromagnetic waves.

[0087] When electromagnetic waves emitted by a base station antenna are incident on this metamaterial structure, the electric field component of the electromagnetic waves induces a current in the outer metal frame. Due to the geometry and conductivity of the outer metal frame, the flow of this current causes it to exhibit an equivalent inductance. Simultaneously, the electric field component also accumulates charge in the uniform gap between the outer metal frame and the inner metal arms, thus forming a distributed capacitance.

[0088] The equivalent inductance of the outer metal frame, the internal metal arms, and the distributed capacitance formed by the uniform gaps together constitute an LC resonant circuit. By precisely designing the geometry and gap width of these metal components, the resonant frequency of this LC resonant circuit can be tuned to the operating frequency of the base station antenna. When the metamaterial structure resonates with the operating frequency of the base station antenna, the unit metal structure will generate a strong coupling effect with the incident electromagnetic wave.

[0089] Through this resonant effect, metamaterial structures can effectively modulate the phase and amplitude of electromagnetic waves. For example, when an electromagnetic wave passes through this metamaterial structure, its phase can be precisely delayed or led, thereby focusing the beam in a specific direction. Simultaneously, by optimizing the geometric parameters of the unit metal structure, the metamaterial structure can achieve good impedance matching with the base station antenna at the operating frequency, reducing signal reflection and maximizing the transmission of electromagnetic energy from the antenna to the target area. Therefore, this metamaterial structure can redirect and focus the signal energy emitted by the base station antenna onto areas with previously existing coverage blind spots, while reducing energy loss due to impedance mismatch, thus significantly enhancing the signal strength and coverage range of the base station antenna in a specific direction.

[0090] Based on the above examples, the metamaterial structure provided in this embodiment demonstrates a significant technical contribution to enhancing base station antenna signals.

[0091] Compared to traditional methods that rely on increasing transmission power or mechanically adjusting antenna angles, the metamaterial structure in this embodiment provides a passive and precise means of electromagnetic wave manipulation. Traditional methods often suffer from high energy consumption, high cost, or limited adjustment accuracy. For example, in the urban environment example described above, simply increasing transmission power to address coverage blind spots would significantly increase the energy consumption of the entire base station and potentially cause unnecessary radiation to non-target areas. This embodiment, however, by designing a unit metal structure with an LC resonant circuit, can specifically resonate with electromagnetic waves at the base station antenna's operating frequency, achieving precise control over the phase and amplitude of the electromagnetic waves. This allows energy to be efficiently guided to the target area, avoiding unnecessary energy waste.

[0092] Furthermore, existing technologies for applying metamaterials to improve antenna performance often focus on optimizing a single performance metric, such as gain enhancement, while neglecting the overall impedance matching between the antenna feed, the metamaterial structure, and the operating environment. Poor matching can actually lead to additional reflection loss due to the introduction of metamaterials. The metamaterial structure in this embodiment, through its LC resonant circuit formed by the metal outer frame, internal metal arms, and uniform gaps in its unit metal structure, can be designed to achieve good impedance matching with the base station antenna at the operating frequency. In the example above, by optimizing the parameters of the LC resonant circuit, reflection loss during signal transmission from the antenna to the metamaterial structure and then to free space can be effectively reduced, ensuring maximum signal energy transmission and avoiding the problem in existing technologies where impedance mismatch negates the gain enhancement effect.

[0093] Furthermore, the metamaterial structure of this embodiment enables precise control of the electromagnetic beam by adjusting the electromagnetic response of the LC resonant circuit. In the example above, traditional fixed-beam or limited-adjustment-range antennas struggle to effectively address coverage blind spots caused by tall buildings. However, the metamaterial structure of this embodiment can reconstruct the phase and amplitude of the incident electromagnetic wave through the resonant characteristics of its elements, thereby achieving beam focusing, redirection, or shaping. This precisely projects signal energy onto the target coverage area, effectively eliminating blind spots. This ability to simultaneously achieve impedance matching and beam adjustment is rare in existing technologies, providing a more comprehensive and efficient solution for base station antenna signal enhancement.

[0094] As can be seen from the above, the metamaterial structure provided in this application includes multiple unit metal structures. Each unit metal structure includes a metal outer frame and an inner metal arm. There is a uniform gap between the metal outer frame and the inner metal arm. The metal outer frame is equivalent to an inductor, and the uniform gap forms a distributed capacitance. The metal outer frame, the inner metal arm, and the uniform gap together constitute an LC resonant circuit for adjusting the electromagnetic response. The electromagnetic response characteristics of the metamaterial structure can be adjusted through the LC resonant circuit, thereby effectively adjusting the overall impedance matching relationship between the base station antenna, the metamaterial structure itself, and the actual deployment environment, and realizing the adaptive conditions of the beam. Ultimately, it solves the technical problems of impedance mismatch and lack of beam control capability, and improves the signal enhancement effect of the base station antenna.

[0095] In other embodiments, this application proposes a method for enhancing base station antenna signals, applied to metamaterial structures as described above, the method comprising: Based on the operating frequency of the base station antenna, determine the target distance between the metamaterial structure and the base station antenna; based on the target distance, position the metamaterial structure in the electromagnetic wave propagation direction of the base station antenna.

[0096] Please see Figure 5 , Figure 5 This is a schematic diagram illustrating a metamaterial structure provided in an embodiment of this application. Figure 5 As shown, the electromagnetic wave propagation direction of the base station antenna is from left to right, and the target distance is D. Therefore, the metamaterial structure can be placed in the electromagnetic wave propagation direction of the base station antenna and at a distance from the base station antenna equal to the target distance.

[0097] The core innovation of this embodiment lies in the fact that by dynamically determining the target distance between the metamaterial structure and the base station antenna according to the operating frequency, and precisely setting the metamaterial structure in the direction of electromagnetic wave propagation, the overall impedance matching problem among the antenna feed, the metamaterial structure, and the operating environment is solved, and the beam shape is finely controlled.

[0098] Specifically, since the electromagnetic properties of metamaterial structures are closely related to their operating frequency, by calculating the target distance based on the operating frequency, it is possible to ensure that the metamaterial structure achieves optimal impedance matching with the base station antenna in a specific frequency band, thereby reducing signal reflection loss. At the same time, this location setting allows the metamaterial structure to effectively control the phase and amplitude of electromagnetic waves, enabling the focusing or redirection of the beam, thereby eliminating coverage blind spots.

[0099] For example, in urban high-rise building obstruction scenarios, this method optimizes the target distance, avoiding the additional reflection loss caused by impedance mismatch in traditional metamaterial solutions, while also taking into account beam adjustment function, efficiently guiding signal energy to the target area.

[0100] Please see Figure 7 , Figure 7 This diagram illustrates test data for a metamaterial structure provided in an embodiment of this application. It can be seen that the metamaterial structure provided in this solution can increase the maximum electric field intensity radiated by the antenna at different frequencies. Therefore, it can be demonstrated that through the above technical solution, this application significantly improves signal coverage quality and transmission efficiency without increasing transmission power or requiring mechanical adjustments, effectively overcoming the limitations of single performance optimization in existing technologies.

[0101] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, refer to the relevant descriptions of other embodiments.

[0102] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0103] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A metamaterial structure for enhancing base station antenna signals, characterized in that, It includes multiple unit metal structures, each of which includes a metal outer frame and an inner metal arm. There is a uniform gap between the metal outer frame and the inner metal arm. The metal outer frame is equivalent to an inductor, and the uniform gap forms a distributed capacitance. The metal outer frame, the inner metal arm, and the uniform gap together constitute an LC resonant circuit for adjusting the electromagnetic response.

2. The metamaterial structure according to claim 1, characterized in that, The shape of the metal outer frame is determined according to the operating frequency of the base station antenna, the type of the base station antenna, and the angle of the electromagnetic waves emitted by the base station antenna.

3. The metamaterial structure according to claim 2, characterized in that, The shape of the internal metal arm is a centrally symmetrical figure with an internal cross structure, and there are rectangular hollow areas in each of the four quadrants corresponding to the cross structure of the internal metal arm that are connected to the uniform gap.

4. The metamaterial structure according to claim 3, characterized in that, The parameters of the uniform gap, and / or the parameters of the rectangular hollow area, and / or the parameters of the cross structure are determined based on the target equivalent capacitance distribution of the metamaterial structure.

5. The metamaterial structure according to claim 4, characterized in that, The parameters of the uniform gap include the width of the uniform gap; the parameters of the rectangular hollow area include the size of the rectangular hollow area; the parameters of the cross structure include the width and shape of the four ends of the cross structure.

6. The metamaterial structure according to claim 1, characterized in that, The unit metal structure includes a first metal structure; the metamaterial structure further includes a first flexible dielectric film, a first adhesive layer, and a dielectric layer, with multiple first metal structures disposed on the first flexible dielectric film, the first adhesive layer disposed in a direction away from the first metal structure of the first flexible dielectric film, and the dielectric layer disposed in a direction away from the first metal structure of the first adhesive layer.

7. The metamaterial structure according to claim 6, characterized in that, The unit metal structure further includes a second metal structure; the metamaterial structure further includes a second flexible dielectric film and a second adhesive layer, the second adhesive layer being disposed in the direction away from the first metal structure of the dielectric layer, the second flexible dielectric film being disposed in the direction away from the first metal structure of the second adhesive layer, and a plurality of second metal structures being disposed in the direction away from the first metal structure of the second flexible dielectric film.

8. The metamaterial structure according to claim 7, characterized in that, The dielectric constants of the first flexible dielectric film, the first adhesive layer, the dielectric layer, the second flexible dielectric film, and the second adhesive layer are determined according to the dielectric constant of the metamaterial structure, and the dielectric constant of the metamaterial structure is determined according to the operating frequency band of the metamaterial structure.

9. The metamaterial structure according to claim 7, characterized in that, The thicknesses of the first flexible dielectric film, the first adhesive layer, the dielectric layer, the second flexible dielectric film, and the second adhesive layer are determined according to the dielectric constant of the metamaterial structure, and the dielectric constant of the metamaterial structure is determined according to the operating frequency band of the metamaterial structure.

10. A method for enhancing base station antenna signals, characterized in that, Applied to the metamaterial structure as described in any one of claims 1 to 9, the method comprises: The target distance between the metamaterial structure and the base station antenna is determined based on the operating frequency of the base station antenna. Based on the target distance, the metamaterial structure is positioned in the electromagnetic wave propagation direction of the base station antenna.

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