Metasurface coating, radome assembly and array antenna

Abstract

This application relates to the field of terminal technologies, and discloses a metasurface coating, a radome assembly, and an array antenna. The array antenna includes a radiation array and the metasurface coating. The radiation array includes at least two radiation array elements. The metasurface coating includes a substrate and a resonant element disposed on the substrate. The metasurface coating is coated on a radiation end of the radiation array element, and a surface of the substrate intersects a radiation direction of the radiation array. For the foregoing array antenna, a sidelobe level of an original array antenna is canceled and suppressed by using the metasurface coating, and a pattern of the array antenna is adjusted by utilizing electromagnetic properties and the resonant element of the substrate, to implement low sidelobe processing of the array antenna. The metasurface coating added to the array antenna is less difficult to mount, and can be directly used in an existing established array antenna. The array antenna has high integration and a compact structure.

Description

TECHNICAL FIELD

[0001] This application relates to the field of terminal technologies, and in particular, to a metasurface coating, a radome assembly, and an array antenna.BACKGROUND

[0002] In a radio technology device, an antenna element is an apparatus for radiating and receiving radio waves and can complete conversion between a high-frequency current / guided wave and a radio wave of a same frequency, and is a basic component of a radio system. For some application scenarios requiring special antenna directivity and gains, a single antenna element cannot meet a performance requirement of a wireless communication system, while array antenna is widely used in the communication field by virtue of its high gains, narrow beams, low sidelobes, and beam scanning or control. The array antenna is an antenna system in which at least two antenna elements are arranged according to a specific rule and can obtain a predetermined radiation characteristic through proper excitation. A single antenna element in the array antenna is a radiation element. Sidelobes are radiation beams other than a maximum radiation beam (that is, a main lobe) on an antenna pattern.

[0003] With rapid development of wireless communication technologies, spectrum resources and site resources are increasingly scarce. The emergence of a spatial division multiplexing technology effectively alleviates the problem of scarcity of spectrum resources and site resources by multiplexing a same frequency band in different spaces to form different radiation beams in different user directions. To improve anti-interference performance between different radiation beams of array antennas, a sidelobe level of the array antenna needs to be further reduced.

[0004] Based on this, low-sidelobe array antennas are increasingly widely used in the field of communication technologies, and research for low sidelobes of the array antennas has accordingly gained more attention from more experts and scholars. Therefore, how to further reduce electromagnetic radiation in an area outside the main lobe and improve performance of the array antenna becomes a technical problem to be urgently resolved in the field of wireless communication technologies.SUMMARY

[0005] In view of this, embodiments of this application provide a metasurface coating, a radome assembly, and an array antenna. The array antenna includes a radiation array and the metasurface coating. The radiation array includes at least two radiation array elements. The metasurface coating includes a substrate and a resonant element disposed on the substrate. The metasurface coating is coated on a radiation end of the radiation array element, and a surface of the substrate intersects a radiation direction of the radiation array. For the foregoing array antenna, a sidelobe level of an original array antenna is canceled and suppressed by using the metasurface coating, and a pattern of the array antenna is adjusted by utilizing electromagnetic properties and the resonant element of the substrate, to implement low sidelobe processing of the array antenna. In addition, the metasurface coating added to the array antenna is less difficult to mount, and can be directly used in an existing established array antenna. Besides, the array antenna has high integration and a compact structure.

[0006] A first aspect of this application provides an array antenna. The array antenna includes a radiation array and a metasurface coating. The radiation array includes at least two radiation array elements. The metasurface coating includes a substrate and a resonant element disposed on the substrate. The metasurface coating is coated on a radiation end of the radiation array element, and a surface of the substrate intersects a radiation direction of the radiation array. The substrate may be considered as a two-dimensional structure, and the surface of the substrate is two large planes on the substrate.

[0007] The radiation direction is a direction in which the radiation array radiates a signal outward, and the radiation direction is a direction in which the at least two radiation array elements radiate a signal outward after being integrated. The metasurface coating is a metamaterial, and the metasurface coating is an artificial layered material whose thickness is less than a wavelength. The metamaterial means a structure (sub-wavelength structure) provided with a resonant element, and a dielectric constant and conductivity of a material are changed through processing. Based on this, the metasurface coating can flexibly and effectively adjust and control characteristics such as polarization, an amplitude, a phase, a polarization mode, and a propagation mode of an electromagnetic wave.

[0008] In some implementations of this application, the metamaterial is a structure in which resonant elements that are periodically distributed are disposed. For example, the periodic distribution may be arranged in rows, columns, or rows and columns, and a distance between adjacent resonant elements is a preset distance. The resonant elements that are periodically distributed on the metamaterial may alternatively be distributed in another form. This is not specifically limited in this application. In some other alternative implementations of this application, the metamaterial is a structure in which resonant elements that are aperiodically distributed are disposed. It may be understood that the aperiodic distribution may be arranged in rows, columns, or rows and columns, and distances between adjacent resonant elements are different. The aperiodic distribution may alternatively be that resonant elements are scattered in a structure without being distributed in a predetermined manner. This is not specifically limited in this application.

[0009] In some implementations of this application, a hollowed-out resonant element may be disposed on the substrate, that is, the resonant element penetrates two surfaces of the substrate. In some other alternative implementations of this application, a convex resonant element may be disposed on the substrate, that is, the resonant element is disposed on the surface of the substrate. For example, convex resonant elements are disposed on both of the two surfaces of the substrate. For another example, a convex resonant element is disposed on one of the surfaces of the substrate. In some other alternative implementations of this application, a concave resonant element may be disposed on the substrate, that is, the resonant element penetrates one of the surfaces of the substrate.

[0010] In other words, in an implementation of this application, the metasurface coating includes the substrate and the resonant element disposed on the substrate, the metasurface coating is coated on the radiation end of the radiation array element, and the radiation direction of the radiation array penetrates the surface of the substrate.

[0011] For the foregoing array antenna, a sidelobe level of an original array antenna is canceled and suppressed through the metasurface coating, and a pattern of the array antenna is adjusted by using electromagnetic properties and the resonant element of the substrate, to implement low sidelobe processing of the array antenna. In addition, the metasurface coating added to the array antenna is less difficult to mount, and may be directly used in an existing array antenna that has been established. Besides, the array antenna has high integration and a compact structure.

[0012] In some possible implementations of the first aspect of this application, in the array antenna, the substrate is configured to adjust transmittance of an electromagnetic wave radiated by the radiation array, and the resonant element is configured to adjust a transmission phase of the electromagnetic wave radiated by the radiation array.

[0013] In some possible implementations of the first aspect of this application, in the array antenna, an outline of the resonant element includes at least one of an "H" shape, a "U" shape, a "C" shape, an "O" shape, a "square" shape, an "X" shape, a "Y" shape, a "Z" shape, a "T" shape, and an "L" shape.

[0014] In some possible implementations of the first aspect of this application, in the array antenna, in the metasurface coating, the substrate specifically includes at least two substrates, and the at least two substrates are stacked along the radiation direction.

[0015] In some possible implementations of the first aspect of this application, in the array antenna, a distance between two adjacent substrates ranges from 3 mm to 7.5 mm, and the distance between the two adjacent substrates is a minimum distance between the two adjacent substrates. The minimum distance between the two substrates may be a minimum value of a distance between any point on one substrate and any point on the other substrate.

[0016] In some possible implementations of the first aspect of this application, in the array antenna, a distance between the two adjacent substrates is 5 mm.

[0017] In some possible implementations of the first aspect of this application, in the array antenna, the metasurface coating further includes: a wave-absorbing component. An orthographic projection of the wave-absorbing component on the substrate is at least partially located in an orthographic projection of the resonant element on the substrate. For example, the wave-absorbing component may be a resistor component, and the resistor component may be a chip resistor.

[0018] In some possible implementations of the first aspect of this application, in the array antenna, the wave-absorbing component includes at least one of the following: a photosensitive resistor, a varistor, and a graphene material.

[0019] In some possible implementations of the first aspect of this application, the array antenna further includes a ground plate (or may be a reflection plate), the ground plate is provided with a first surface made of a conductive material, and the radiation array is disposed on the first surface of the ground plate.

[0020] In some possible implementations of the first aspect of this application, the array antenna further includes a radome, the radome and the ground plate jointly form an accommodating cavity, the radiation array element is located within the accommodating cavity, and a layout position of the metasurface coating relative to the radome includes at least one of the following: the metasurface coating is located within the accommodating cavity; or the metasurface coating is located outside the accommodating cavity; or a mounting cavity is formed in the radome, the mounting cavity is located on a side that is of the radiation array element and that faces away from the ground plate, and the metasurface coating is disposed in the mounting cavity.

[0021] A second aspect of this application provides a metasurface coating. The metasurface coating includes a substrate and a resonant element disposed on the substrate.

[0022] A third aspect of this application provides a radome assembly. The radome assembly includes a radome and a metasurface coating. The metasurface coating includes a substrate and a resonant element disposed on the substrate.BRIEF DESCRIPTION OF DRAWINGS

[0023] FIG. 1(a) shows an application scenario of an array antenna 1a and an array antenna 1b according to some embodiments of this application; FIG. 1(b) shows another application scenario of an array antenna 1c and an array antenna 1d according to some embodiments of this application; FIG. 2 is a diagram of an excitation system of an array antenna 1 according to some embodiments of this application; FIG. 3 is a diagram in which a T / R component of an array antenna 1 is connected to an array antenna according to some embodiments of this application; FIG. 4(a) is a three-dimensional diagram of an array antenna 1 according to some embodiments of this application; FIG. 4(b) is an exploded view of an array antenna 1 according to some embodiments of this application; FIG. 4(c) is a sectional view of an array antenna 1 along a section A-A in FIG. 4(a) according to some embodiments of this application; FIG. 4(d) is a top view of a metasurface coating 30 in an array antenna 1 according to some embodiments of this application; FIG. 5 is a simulation diagram of a pattern of an array antenna 1 according to some embodiments of this application; FIG. 6(a) is a sectional view of an array antenna 1 along a section A-A in FIG. 4(a) according to some embodiments of this application, where a pattern of the array antenna 1 is further shown; FIG. 6(b) is a principle diagram of a pattern of an array antenna 1 according to some embodiments of this application; FIG. 6(c) is a three-dimensional diagram of an array antenna 1' according to some embodiments of this application; FIG. 6(d) is a sectional view of an array antenna 1' along a section A-A in FIG. 4(a) according to some embodiments of this application; FIG. 6(e) is a sectional view of an array antenna 1' along a section A-A in FIG. 4(a) according to some embodiments of this application, where a pattern of an array antenna 1 is further shown; FIG. 7(a) is a sectional view of an array antenna 1 along a section A-A in FIG. 4(a) according to some embodiments of this application; FIG. 7(b) is a sectional view of an array antenna 1 along a section A-A in FIG. 4(a) according to some embodiments of this application, where a metasurface coating 30 is not shown; FIG. 7(c) is a sectional view of the array antenna 1 corresponding to FIG. 7(b) along the section A-A in FIG. 4(a) according to some embodiments of this application; FIG. 8(a) is an outline diagram of a resonant element 2001 on a substrate 100 in a metasurface coating 30 according to some embodiments of this application; FIG. 8(b) is an outline diagram of a resonant element 2002 on a substrate 100 in a metasurface coating 30 according to some embodiments of this application; FIG. 8(c) is an outline diagram of a resonant element 2003 on a substrate 100 in a metasurface coating 30 according to some embodiments of this application; FIG. 8(d) is an outline diagram of a resonant element 2004 on a substrate 100 in a metasurface coating 30 according to some embodiments of this application; FIG. 8(e) is an outline diagram of a resonant element 2005 on a substrate 100 in a metasurface coating 30 according to some embodiments of this application; FIG. 8(f) is an outline diagram of a resonant element 2006 on a substrate 100 in a metasurface coating 30 according to some embodiments of this application; FIG. 9(a) is a top view of a substrate 100a in a metasurface coating 30 according to some embodiments of this application; FIG. 9(b) is a sectional view of a substrate 100a in a metasurface coating 30 along a section B-B in FIG. 9(a) according to some embodiments of this application; FIG. 9(c) is a sectional view of a substrate 100b in a metasurface coating 30 along a section B-B in FIG. 9(a) according to some embodiments of this application; FIG. 9(d) is a sectional view of a substrate 100c in a metasurface coating 30 along a section B-B in FIG. 9(a) according to some embodiments of this application; FIG. 10(a) is a top view of a substrate 100d in a metasurface coating 30 according to some embodiments of this application; FIG. 10(b) is a sectional view of a substrate 100e in a metasurface coating 30 along a section B-B in FIG. 9(a) according to some embodiments of this application; FIG. 10(c) is a sectional view of a substrate 100f in a metasurface coating 30 along a section B-B in FIG. 9(a) according to some embodiments of this application; FIG. 11(a) is a three-dimensional diagram of an array antenna 1 according to some embodiments of this application; FIG. 11(b) is an exploded view of an array antenna 1 according to some embodiments of this application; FIG. 12(a) is a sectional view of an array antenna 1 along a section C-C in FIG. 11(a) according to some embodiments of this application; FIG. 12(b) is a partial enlarged view of an area S 2 in FIG. 12(a); FIG. 13(a) is a tiled diagram of a combination scheme of a substrate 100a and a substrate 100a in a metasurface coating 30 according to some embodiments of this application; FIG. 13(b) is a sectional view of a combination scheme of a substrate 100a and a substrate 100a in a metasurface coating 30 along a section C-C in FIG. 11(a) according to some embodiments of this application; FIG. 14(a) is a tiled diagram of a combination scheme of a substrate 100a and a substrate 100a' in a metasurface coating 30 according to some embodiments of this application; FIG. 14(b) is a tiled diagram of a combination scheme of a substrate 100a and a substrate 100a" in a metasurface coating 30 according to some embodiments of this application; FIG. 15(a) shows a design scheme of a metasurface coating 30 in an array antenna 1 according to some embodiments of this application; FIG. 15(b) is a simulation pattern of an array antenna 1 according to some embodiments of this application; and FIG. 16 is a simulation pattern of an array antenna 1 according to some embodiments of this application. DESCRIPTION OF EMBODIMENTS

[0024] To make the objectives, technical solutions, and advantages of this application clearer, the following further describes the implementations of this application in detail with reference to the accompanying drawings.

[0025] Spatial division multiplexing (Spatial Division Multiplexing, SDM): The spatial division multiplexing technology is a technical solution that enables a same frequency band to be multiplexed in different spaces to form different radiation beams in different user directions.

[0026] Pattern: The pattern is a pattern in which a radiation electromagnetic field of an antenna is distributed along angular coordinates at a fixed distance.

[0027] Main lobe: The main lobe is a maximum radiation beam in an antenna pattern.

[0028] Sidelobe: The sidelobe is a radiation beam other than the maximum radiation beam in the antenna pattern.

[0029] Power divider: The power divider is a device that divides energy of one channel of input signal into two or more channels for equal or unequal output.

[0030] To resolve the foregoing problem that spectrum resources and site resources are increasingly scarce, an array antenna in some technical solutions of this application may be applicable to a spatial division multiplexing technology. The following describes in detail with reference to the accompanying drawings. FIG. 1(a) shows an application scenario to which an antenna system S 1 is applicable according to some embodiments of this application. As shown in FIG. 1(a), the antenna system S 1 may include an array antenna 1a and an array antenna 1b. The array antenna 1a corresponds to a first user direction, and the array antenna 1b corresponds to a second user direction, to implement frequency multiplexing, thereby effectively alleviating the problem that spectrum resources and site resources are increasingly scarce. It may be understood that the antenna system S 1 may further include another array antenna. For example, the antenna system S 1 includes an array antenna. For ease of description, the following continues to use an example in which the antenna system S 1 includes the array antenna 1a and the array antenna 1b for description.

[0031] As shown in FIG. 1(a), the array antenna 1a corresponds to the first user direction, a main lobe in the first user direction corresponds to a first user U 1 , and a pattern of the array antenna 1a includes a main lobe ML 1 , a sidelobe SL 11 , and a sidelobe SL 12 ; and the array antenna 1b corresponds to the second user direction, a main lobe in the second user direction corresponds to a second user U 2 , and a pattern of the array antenna 1b includes a main lobe ML 2 , a sidelobe SL 21 , and a sidelobe SL 22 . It is not difficult to find from FIG. 1(a) that the main lobe ML 1 and the sidelobe SL 21 overlap in a direction, and the sidelobe SL 21 interferes with the main lobe ML 1 ; and the main lobe ML 2 and the sidelobe SL 12 overlap in a direction, and the sidelobe SL 12 interferes with the main lobe ML 2 . In addition, the sidelobe SL 11 and the sidelobe SL 21 interfere with each other, and the sidelobe SL 12 and the sidelobe SL 22 interfere with each other. Based on this, low sidelobe processing needs to be performed on the array antenna 1a and the array antenna 1b, to strictly restrict distribution of the array antenna 1a and the array antenna 1b in space, thereby ensuring that the array antenna 1a and the array antenna 1b do not interfere with each other when they work together.

[0032] It may be understood that the antenna system S 1 shown in FIG. 1(a) is one of implementations. In some other application scenarios, the antenna system S 1 includes an array antenna, and the array antenna can form two beams with different main lobe directions (equivalent to a beam formed by the array antenna 1a and a beam formed by the array antenna 1b). Details are not described herein.

[0033] In some application scenarios, the array antenna 1 needs to correspondingly adjust the array pattern based on a surrounding environment or a change in a surrounding environment, so that in addition to ensuring normal radiation in a main lobe area, a sidelobe area of the array antenna 1 needs to be suppressed. FIG. 1(b) shows another application scenario of an antenna system S 2 and an antenna system S 3 according to some embodiments of this application. As shown in FIG. 1(b), the antenna system S 2 may include an array antenna 1c, the array antenna 1c corresponds to a third user direction, a main lobe in the third user direction corresponds to a third user U 3 , and a pattern of the array antenna 1c includes a main lobe ML 3 , a sidelobe SL 31 , and a sidelobe SL 32 .

[0034] However, a surrounding environment of the array antenna 1c changes. For example, a fourth user U 4 is added around the array antenna 1c (for example, a new residential building or shopping mall is built around the array antenna 1c). The sidelobe SL 32 of the array antenna 1c interferes with communication of the fourth user U 4 . Based on this, low sidelobe processing needs to be performed on the array antenna 1c in a target area, and corresponding adjustment needs to be performed based on the pattern of the array antenna, to ensure that the array antenna 1c does not affect normal communication of the fourth user U 4 . The antenna system S 3 may include an array antenna 1d, the array antenna 1d corresponds to a fourth user direction, a main lobe in the fourth user direction corresponds to a fourth user U 4 , and a pattern of the array antenna 1d includes a main lobe ML 4 , a sidelobe SL 41 , and a sidelobe SL 42 . The sidelobe SL 41 of the array antenna 1d interferes with communication of the third user U 3 .

[0035] Currently, sidelobe suppression of an array antenna is implemented mainly by adjusting an excitation amplitude and phase of each antenna element in the array antenna or adjusting a distance between antenna elements in the array.

[0036] In some implementations of this application, a specially designed power divider may be used to perform precise power allocation, to adjust the excitation amplitude and phase of each antenna element in the array antenna. FIG. 2 is a diagram of an excitation system of an antenna system S according to some embodiments of this application. As shown in FIG. 2, in some embodiments of this application, the antenna system S includes an array antenna 1 and a passive power divider 2. The array antenna 1 uses a feeding system in a form of the passive power divider 2 as an excitation system. A specific dimension and a branch parameter of the passive power divider 2 are designed for the array antenna 1, so that total port energy can be fed into each port according to a specific proportion. The total port energy includes parameters such as an amplitude and a phase.

[0037] In some implementations, the passive power divider 2 may be a microstrip power divider, a substrate integrated waveguide (Substrate Integrated Waveguide, SIW) power divider, or the like. This is not specifically limited in this application.

[0038] In the foregoing antenna system S, although sidelobe suppression of the array antenna can be implemented through a plurality of iterative designs of the array antenna 1 and the passive power divider 2, a long design time is required. However, the passive power divider 2 usually causes a power division error due to array coupling, an element mismatch, or the like, consequently causing sidelobe elevation. In addition, for some array antennas 1 that require asymmetric patterns, excitation amplitudes and phases of radiation array elements in the array antenna 1 are usually different. Therefore, a plurality of passive power dividers 2 with unequal amplitudes and different phases need to be designed, to effectively excite antenna ports.

[0039] For a passive power divider 2 with a plurality of ports and having unequal amplitudes and different phases, it is difficult to design the passive power divider 2, and it is difficult to achieve that an amplitude and a phase output by each port are close to a design value. In addition, due to a principle limitation of the passive power divider 2 such as coupling between the passive power dividers 2 and uncontrollable output port structures, each output port usually has a poor match with the antenna. Consequently, an amplitude and a phase of energy actually input by each radiation array element deviate greatly from an ideal value, and then an effect of a final pattern differs greatly from an ideal situation. Then, because the passive power divider 2 is generally integrated below the array antenna 1, the passive power divider 2 inevitably causes specific coupling interference to the array antenna 1, and consequently performance of the array antenna 1 deteriorates. Besides, the passive power divider 2 is a static feeding system, cannot be adjusted, and does not support array pattern beam scanning, that is, cannot perform phase scanning.

[0040] In some other technical solutions of this application, a high-precision transceiver T / R component may be used to adjust an excitation amplitude and phase of each antenna element in the array antenna. FIG. 3 is a diagram in which a T / R component of the array antenna 1 is connected to an array antenna according to some embodiments of this application. As shown in FIG. 3, the T / R component may be connected to an array antenna (not shown in FIG. 3) through a digital control circuit, to implement signal amplitude and phase adjustment, and then spatially implement beamforming and scanning of the antenna. Main components of the digital control circuit include related components such as an attenuator, a phase shifter, and a power amplifier. The digital control circuit may directly control an output amplitude and phase of each T / R component, to complete feeding of the array antenna.

[0041] Currently, a high-precision T / R component can implement phase stepping of approximately 5°, and regulation precision of the T / R component is in line with general engineering application. Based on this, currently, a method for implementing a low sidelobe is mainly to separately excite each radiation array element in a form of a T / R component or a power divider, to superimpose radiation array element patterns in the space area to implement a low sidelobe effect. If a power division network is used for implementation, the difference between the low sidelobe effect and an ideal value is large and a working bandwidth is narrow. However, in a current T / R component, a high-order phase shifter is expensive and difficult to integrate. Although an ultra-low sidelobe requirement can be implemented, a cost is quite high. For some established array antennas, if sidelobe suppression needs to be implemented in some areas due to a change of a surrounding environment, the array antennas need to be dismounted and mounted, and a power division network needs to be redesigned and mounted. This is quite costly in engineering and difficult to implement.

[0042] However, in an actual application, the high-precision T / R component is expensive due to difficulty in forming, and an insertion loss of the high-precision T / R component is excessively large, resulting in a high engineering implementation cost. In addition, a high bit has a high requirement on a material design of a component, and a control system is complex.

[0043] In some other technical solutions of this application, a subarray cancellation technology may be used to implement sidelobe suppression of an array antenna. Specifically, a relative quantity of auxiliary antennas are added on the basis of a main antenna pointing to a signal receiving direction to cancel a sidelobe level spatially, thereby implementing sidelobe suppression of the array antenna.

[0044] In the antenna system S, several additional auxiliary antennas are added around a target antenna, and suppression and cancellation are performed on a sidelobe level in a sidelobe area based on a wave path difference and an excitation difference between the auxiliary antenna and the target antenna, to implement low sidelobe processing of the array antenna. However, in this solution, several additional auxiliary antennas need to be added around the target antenna, that is, several additional radiation array elements need to be added around a target array. Therefore, a design is complex and a cost is high. In addition, the cancellation technology needs to accurately place each radiation array element, and this has a high requirement on mounting and processing. Besides, a quantity of sidelobes to be canceled is related to a quantity of added radiation array elements, which is generally applicable only to sidelobe suppression at a small quantity of specific angles, and an application scope is narrow.

[0045] To implement low sidelobe processing of an array antenna, this application provides an array antenna. In the array antenna, a metasurface coating for amplitude and phase distribution characteristics of a low sidelobe array antenna is added to an original array antenna. The metasurface coating includes a substrate and a resonant element disposed on the substrate, and the substrate is a layered structure of an artificial electromagnetic structure material. The metasurface coating is coated on a radiation end of a radiation array element in a radiation array of the original array antenna, and a surface of the substrate intersects a radiation direction of the radiation array. The substrate is configured to adjust transmittance of an electromagnetic wave radiated by the radiation array, and the resonant element is configured to adjust a transmission phase of the electromagnetic wave radiated by the radiation array.

[0046] In some embodiments of this application, the metasurface coating is a metamaterial, and the metasurface coating is an artificial layered material whose thickness is less than a wavelength. The metamaterial means a structure (sub-wavelength structure) provided with a resonant element, and a dielectric constant and conductivity of a material are changed through processing. Based on this, the metasurface coating can flexibly and effectively adjust and control characteristics such as polarization, an amplitude, a phase, a polarization mode, and a propagation mode of an electromagnetic wave.

[0047] In some implementations of this application, the metamaterial is a structure in which resonant elements that are periodically distributed are disposed. For example, the periodic distribution may be arranged in rows, columns, or rows and columns, and a distance between adjacent resonant elements is a preset distance. The resonant elements that are periodically distributed on the metamaterial may alternatively be distributed in another form. This is not specifically limited in this application.

[0048] In some other alternative implementations of this application, the metamaterial is a structure in which resonant elements that are aperiodically distributed are disposed. It may be understood that the aperiodic distribution may be arranged in rows, columns, or rows and columns, and distances between adjacent resonant elements are different. The aperiodic distribution may alternatively be that resonant elements are scattered in a structure without being distributed in a predetermined manner. This is not specifically limited in this application.

[0049] It may be understood that the foregoing several implementations are merely some implementations of a distribution manner of resonant elements on the substrate. In this application, the foregoing implementations may be regrouped and adaptively adjusted based on an actual requirement. A deformed implementation also falls within the protection scope of this application. This is not specifically limited in this application.

[0050] In some implementations of this application, a hollowed-out resonant element may be disposed on the substrate, that is, the resonant element penetrates two surfaces of the substrate.

[0051] In some other alternative implementations of this application, a convex resonant element may be disposed on the substrate, that is, the resonant element is disposed on the surface of the substrate. For example, convex resonant elements are disposed on both of the two surfaces of the substrate. For another example, a convex resonant element is disposed on one of the surfaces of the substrate.

[0052] In some other alternative implementations of this application, a concave resonant element may be disposed on the substrate, that is, the resonant element penetrates one of the surfaces of the substrate.

[0053] It may be understood that the foregoing several implementations are merely some implementations of forms of the resonant elements on the substrate. In this application, the foregoing implementations may be regrouped and adaptively adjusted based on an actual requirement. A deformed implementation also falls within the protection scope of this application. This is not specifically limited in this application.

[0054] For ease of description, the following uses an example in which a periodically distributed hollow-out resonant element is disposed on the substrate for description, that is, the following uses an example in which a resonant element 200 is a slot structure disposed on the substrate for description.

[0055] This application provides a metasurface coating design applicable to an array antenna. The metasurface coating can implement a low sidelobe characteristic of the array antenna without changing an original array. In the array antenna, a lower sidelobe can improve a signal-to-noise ratio, reduce impact of a clutter signal outside a main beam, and effectively improve an anti-interference capability of an entire system. For the foregoing array antenna, a sidelobe level of an original array antenna is canceled and suppressed through the metasurface coating, and a pattern of the array antenna is adjusted by using electromagnetic properties and the resonant element of the substrate, to implement low sidelobe processing of the array antenna. In addition, the metasurface coating added to the array antenna is less difficult to mount, and may be directly used in an existing array antenna that has been established. Besides, the array antenna has high integration and a compact structure.

[0056] In some embodiments of this application, in the metasurface coating, a structure dimension of the metasurface coating is optimized, and transmittance and a transmittance phase of an artificial electromagnetic structure material are adjusted, so that different transmittance amplitudes and phase differences are generated when electromagnetic waves radiated by the radiation array elements pass through a metasurface. The foregoing array antenna is equivalent to adjusting and controlling an excitation amplitude and phase of each radiation array element, to adjust and control a pattern of each radiation array element, thereby implementing a low sidelobe effect of the array antenna.

[0057] In some implementations of this application, the structure dimension of the metasurface coating may include a thickness of the substrate, an outline shape of the resonant element, an outline dimension of the resonant element, and the like. This is not specifically limited in this application.

[0058] In some embodiments of this application, the metasurface coating may also be used in an array antenna loaded by a power divider, to correct a sidelobe level elevation phenomenon caused by an error introduced by the power divider. In comparison with a conventional power divider design, the array antenna in this application has advantages such as a simple structure, a short research and development cycle, and a low cost.

[0059] The following describes the technical solutions of this application in detail with reference to a specific structure.

[0060] FIG. 4(a) is a three-dimensional diagram of an array antenna 1 according to some embodiments of this application. FIG. 4(b) is an exploded view of the array antenna 1 according to some embodiments of this application. FIG. 4(c) is a sectional view of the array antenna 1 along a section A-A in FIG. 4(a) according to some embodiments of this application. With reference to FIG. 4(a) to FIG. 4(c), it can be learned that this application provides the array antenna 1. In some embodiments of this application, the array antenna 1 may include a ground plate 10, a radiation array 20, a metasurface coating 30, and a radome 40. The radiation array 20 includes at least two radiation array elements, and the ground plate 10 and the radome 40 jointly form an accommodating cavity 50. The radiation array 20 is located within the accommodating cavity 50, and the radiation array 20 is distributed on the ground plate 10. For example, the radiation array 20 is located on a surface of the ground plate 10. The metasurface coating 30 is located on a side that is of the radiation array 20 and that faces away from the ground plate 10. FIG. 4(d) is a top view of the metasurface coating 30 in the array antenna 1 according to some embodiments of this application. As shown in FIG. 4(d), the metasurface coating 30 includes a substrate 100 and a hollowed-out resonant element 200 disposed on the substrate 100. The resonant element 200 is a slot structure. The ground plate 10 may be a component that can implement a grounding function, for example, a mounting bracket in an antenna system. This is not specifically limited in this application.

[0061] In addition, directions of the array antenna 1 are defined with reference to FIG. 4(a) to FIG. 4(c). The surface of the ground plate 10 is defined as an XOY plane, an extension direction of an opposite side of the surface of the ground plate 10 is defined as an X-axis, an extension direction of the other opposite side is defined as a Y-axis, and a direction in which the radiation array 20 and the ground plate 10 are stacked is defined as a Z-axis.

[0062] For the array antenna 1, the metasurface coating 30 is introduced above the radiation array 20 in the original array antenna, so that a beamforming characteristic can be directly implemented without changing a feeding structure of the antenna. Based on this, the array antenna 1 in this application has characteristics such as a low cost, low engineering complexity, and simple implementation in comparison with a design of a power division feeding network or a T / R component.

[0063] It may be understood that the design scheme in this application is further applicable to an array antenna in another form. For an array antenna in another form, the metasurface coating 30 is coated on the radiation end of the radiation array element in the radiation array, and the surface of the substrate 100 in the metasurface coating 30 intersects the radiation direction of the radiation array.

[0064] It may be understood that a relative position of the metasurface coating 30 relative to the accommodating cavity 50 is not specifically limited in this application, and any metasurface coating 30 located on the side that is of the radiation array 20 and that faces away from the ground plate 10 falls within the protection scope of this application. The relative position of the metasurface coating 30 relative to the accommodating cavity 50 is described in detail below. Details are not described herein again.

[0065] In some implementations of this application, as shown in FIG. 4(c), the radome 40 is a semi-closed housing structure, the radome 40 is disposed on the ground plate 10, and the ground plate 10 and the radome 40 jointly form the accommodating cavity 50.

[0066] In some other alternative implementations of this application, the radome 40 is a closed housing structure, the radome 40 includes a first cover body and a second cover body, the first cover body and the second cover body jointly form a closed cavity, and the ground plate 10 is located in the closed cavity and mounted on the second cover body. The ground plate 10, the first cover body, and the second cover body jointly form the accommodating cavity 50.

[0067] In some embodiments of this application, a quantity of substrates 100 in the metasurface coating 30 may be one, two, three, four, or the like. This is not specifically limited in this application. In addition, when there are a plurality of substrates 100, the plurality of substrates 100 may be stacked in layers, or may be arranged sequentially in parallel. This is not specifically limited herein.

[0068] FIG. 5 is a simulation diagram of a pattern of the array antenna 1 according to some embodiments of this application. In a horizontal direction, u represents a horizontal angle in a spatial angle, for example, u is a ratio of the horizontal angle in the spatial angle to 180°; v represents a pitch angle in the spatial angle, for example, v is a ratio of the pitch angle in the spatial angle to 180°; and a vertical axis direction is a relative amplitude of a radiation beam, and a unit is dB. As shown in FIG. 5, the pattern of the array antenna 1 includes a main lobe ML (for example, a black radiation beam in FIG. 5) and a sidelobe SL (for example, a gray radiation beam in FIG. 5). A difference between a relative amplitude of the main lobe ML and a relative amplitude of the sidelobe SL is large, and is approximately 10 dB, that is, low sidelobe processing of the array antenna 1 is implemented.

[0069] FIG. 6(a) is a sectional view of the array antenna 1 along the section A-A in FIG. 4(a) according to some embodiments of this application, where the pattern of the array antenna 1 is further shown. FIG. 6(b) is a principle diagram of the pattern of the array antenna 1 according to some embodiments of this application.

[0070] The following describes in detail a principle of the array antenna 1 in this application with reference to FIG. 6(a) and FIG. 6(b). In the metasurface coating 30, a transmission phase may be changed by adjusting a size of a slot of the resonant element 200. A specific optimized value of the slot is determined by a required sidelobe level. According to a feature of the sidelobe level, an actual feeding phase value of each radiation array element is obtained by using an array analysis and integration method, then a phase difference that needs to be satisfied by the slot of the resonant element 200 is calculated, and finally the dimension of the slot of the resonant element 200 corresponding to a corresponding radiation array element is deduced. The metasurface coating 30 may adjust and control a pattern of each radiation array element (for example, P 2 in FIG. 6(b)). An effect thereof is equivalent to changing amplitude and phase distribution of the array antenna 1, and finally a low sidelobe effect (for example, P 1 in FIG. 6(a) and FIG. 6(b)) of the array antenna 1 is implemented.

[0071] FIG. 6(c) is an exploded view of an array antenna 1' according to some embodiments of this application. FIG. 6(d) is a sectional view of the array antenna 1' along the section A-A in FIG. 4(a) according to some embodiments of this application. As shown in FIG. 6(c) and FIG. 6(d), in some embodiments of this application, the array antenna 1' may include a ground plate 10, a radiation array 20, and a radome 40. The ground plate 10 and the radome 40 jointly form an accommodating cavity 50. The radiation array 20 is located within the accommodating cavity 50, the radiation array 20 is distributed on the ground plate 10, and the radiation array 20 includes at least two radiation array elements. It may be understood that the ground plate 10, the radiation array 20, and the radome 40 in the array antenna 1' are the same as the ground plate 10, the radiation array 20, and the radome 40 in the array antenna 1. Details are not described herein again.

[0072] FIG. 6(e) is a sectional view of the array antenna 1' along the section A-A in FIG. 4(a) according to some embodiments of this application, where a pattern (for example, P 1 ') of the array antenna 1' is further shown. A size of a radiation beam (for example, a main lobe ML' and a sidelobe SL' in FIG. 6(e)) represents a relative amplitude of the radiation beam. As shown in FIG. 6(e), in some embodiments of this application, a group of radiation beams is formed on each radiation array element in the array antenna 1', and in patterns formed after the groups of radiation beams interact with each other outside the radome 40, relative amplitudes (for example, a main lobe ML' in FIG. 6(e)) of some radiation beams are large, and relative amplitudes (for example, a sidelobe SL' in FIG. 6(e)) of other radiation beams are small. It is not difficult to find that a relative amplitude of the main lobe ML' of the array antenna 1' is similar to a relative amplitude of the sidelobe SL', that is, a sidelobe level of the array antenna 1' is high.

[0073] The following further describes in detail a layout position of the metasurface coating 30 in the array antenna 1 with reference to the accompanying drawings.

[0074] Still refer to FIG. 6(a). It can be learned that, in some embodiments of this application, as shown in FIG. 6(a), the metasurface coating 30 is located within the accommodating cavity 50 and is mounted on the radome 40. For the array antenna 1, the metasurface coating 30 is mounted in the accommodating cavity 50, to avoid external interference to the metasurface coating 30, improve stability of the metasurface coating 30, and prolong a service life of the array antenna 1.

[0075] In some implementations of this application, the metasurface coating 30 may be mounted on the radome 40 in a manner of adhesive bonding, welding connection, thread connection, or the like, and the metasurface coating 30 may also be mounted on the radome 40 in another manner. This is not specifically limited herein.

[0076] In some other alternative implementations of this application, the array antenna 1 further includes a mounting bracket (not shown in the figure), and the metasurface coating 30 is mounted on the radome 40 by using the mounting bracket.

[0077] FIG. 7(a) is a sectional view of the array antenna 1 along the section A-A in FIG. 4(a) according to some other embodiments of this application. As shown in FIG. 7(a), in some embodiments of this application, the metasurface coating 30 is located outside the accommodating cavity 50. For the array antenna 1, the metasurface coating 30 is mounted outside the accommodating cavity 50, so that mounting difficulty is low, and it is convenient to update an existing array antenna to the array antenna in this application.

[0078] FIG. 7(b) is a sectional view of the array antenna 1 along the section A-A in FIG. 4(a) according to some embodiments of this application, where the metasurface coating 30 is not shown. FIG. 7(c) is a sectional view of the array antenna 1 corresponding to FIG. 7(b) along the section A-A in FIG. 4(a) according to some embodiments of this application.

[0079] In some embodiments of this application, as shown in FIG. 7(b), a mounting cavity 60 is formed in the radome 40, and the mounting cavity 60 is located on the side that is of the radiation array 20 and that faces away from the ground plate 10. As shown in FIG. 7(c), the metasurface coating 30 is disposed in the mounting cavity 60, to ensure that the metasurface coating 30 is located on the side that is of the radiation array 20 and that faces away from the ground plate 10.

[0080] It may be understood that the layout position of the metasurface coating 30 relative to the radome 40 may be at least one of the foregoing implementations. For example, there may be at least two metasurface coatings 30 in the array antenna 1, and layout manners of the at least two metasurface coatings 30 relative to the radome 40 may be the same or may be different. That is, at least one of the foregoing layout positions may be used for the at least two metasurface coatings 30.

[0081] Based on this, the layout position of the metasurface coating 30 relative to the radome 40 is not specifically limited in this application, and any layout position of the metasurface coating 30 relative to the radome 40 falls within the protection scope of this application.

[0082] After the overall structure of the array antenna 1 is described, the following describes in detail several hollowed-out resonant elements 200 disposed on the substrate 100. An outline of the resonant element 200 is an outline projected by the resonant element 200 on the surface of the ground plate 100.

[0083] FIG. 8(a) is an outline diagram of the resonant element 200 (a resonant element 2001) on the substrate 100 in the metasurface coating 30 according to some embodiments of this application. In some embodiments of this application, as shown in FIG. 8(a), an outline of the resonant element 2001 on the substrate 100 may be an "H" shape. A dimension d 11 , a dimension d 12 , a dimension d 13 , a dimension d 14 , and a dimension d 15 are structure dimensions of the "H"-shaped resonant element 2001. It may be understood that FIG. 8(a) shows only some structure dimensions of the "H"-shaped resonant element 2001, and the structure dimensions of the "H"-shaped resonant element 2001 may be other dimensions, for example, a thickness of the resonant element 2001 (a dimension in a Z-axis direction). This is not specifically limited in this application.

[0084] FIG. 8(b) is an outline diagram of the resonant element 200 (a resonant element 2002) on the substrate 100 in the metasurface coating 30 according to some embodiments of this application. In some embodiments of this application, as shown in FIG. 8(b), an outline of the resonant element 2002 on the substrate 100 may be a "U" shape. A dimension d 21 , a dimension d 22 , a dimension d 23 , a dimension d 24 , and a dimension d 25 are structure dimensions of the "U"-shaped resonant element 2002. Similarly, FIG. 8(b) shows only some structure dimensions of the "U"-shaped resonant element 2002. Details are not described herein again. It may be understood that, in some other embodiments of this application, the outline of the resonant element 2002 on the substrate 100 may alternatively be a "C" shape.

[0085] FIG. 8(c) is an outline diagram of the resonant element 200 (a resonant element 2003) on the substrate 100 in the metasurface coating 30 according to some embodiments of this application. In some embodiments of this application, as shown in FIG. 8(c), an outline of the resonant element 2003 on the substrate 100 may be an "O" shape. A dimension d 31 , a dimension d 32 , and a dimension d 33 are structure dimensions of the "O"-shaped resonant element 2003. When the outline of the resonant element 2003 on the substrate 100 may be the "O" shape, a connecting component (not shown in the figure) may be further disposed in the metasurface coating 30, to connect inner and outer parts of the "O" shape by using the connecting component. Similarly, FIG. 8(c) shows only some structure dimensions of the "O"-shaped resonant element 2003. Details are not described herein again. It may be understood that, in some other embodiments of this application, the outline of the resonant element 2003 on the substrate 100 may alternatively be a "square" shape.

[0086] FIG. 8(d) is an outline diagram of the resonant element 200 (a resonant element 2004) on the substrate 100 in the metasurface coating 30 according to some embodiments of this application. In some embodiments of this application, as shown in FIG. 8(d), an outline of the resonant element 2004 on the substrate 100 may be a "+" shape. A dimension d 41 , a dimension d 42 , a dimension d 43 , a dimension d 44 , a dimension d 45 , and a dimension d 46 are structure dimensions of the "+"-shaped resonant element 2004. Similarly, FIG. 8(d) shows only some structure dimensions of the "+"-shaped resonant element 2003. Details are not described herein again. It may be understood that, in some other embodiments of this application, the outline of the resonant element 2004 on the substrate 100 may alternatively be any one of a "-" shape, a "|" shape, a "\" shape, and a " / " shape.

[0087] FIG. 8(e) is an outline diagram of the resonant element 200 (a resonant element 2005) on the substrate 100 in the metasurface coating 30 according to some embodiments of this application. In some embodiments of this application, as shown in FIG. 8(e), an outline of the resonant element 2005 on the substrate 100 may be an "X" shape.

[0088] FIG. 8(f) is an outline diagram of the resonant element 200 (a resonant element 2006) on the substrate 100 in the metasurface coating 30 according to some embodiments of this application. In some embodiments of this application, as shown in FIG. 8(f), an outline of the resonant element 2004 on the substrate 100 may be a "Y" shape. In some embodiments of this application, the outline of the resonant element 2006 on the substrate 100 may be any one of a "Z" shape, a "T" shape, and an "L" shape.

[0089] It may be understood that different implementations of the outline of the resonant element 200 on the substrate 100 are merely some examples, and implementations of outlines of other resonant elements 200 also fall within the protection scope of this application. This is not specifically limited in this application.

[0090] After the specific structure of the resonant element 200 on the substrate 100 in the metasurface coating 30 is described, the following further describes in detail a single substrate 100 in the metasurface coating 30 with reference to the accompanying drawings.

[0091] Outlines of at least two resonant elements 200 on the single substrate 100 may be the same or may be different, which is not specifically limited in this application. That the outlines of the two resonant elements 200 are different means that at least one of a thickness of the substrate 100 and the structure dimension (for example, the dimensions shown in FIG. 8(a), FIG. 8(b), and FIG. 8(c), and details being not described herein) of the resonant element 200 is different.

[0092] In some embodiments of this application, a plurality of resonant elements are disposed on the substrate, and the plurality of resonant elements are the same. That the plurality of resonant elements are the same means that all structure dimensions of the plurality of resonant elements are correspondingly the same. For example, all structure dimensions of the plurality of resonant elements specifically include the dimensions shown in FIG. 8(a), FIG. 8(b), FIG. 8(c), and FIG. 8(d), and dimensions of the plurality of resonant elements in a thickness direction of the substrate 100.

[0093] FIG. 9(a) is a top view of a substrate 100a in the metasurface coating 30 according to some embodiments of this application. FIG. 9(b) is a sectional view of the substrate 100a in the metasurface coating 30 along a section B-B in FIG. 9(a) according to some embodiments of this application.

[0094] In some embodiments of this application, as shown in FIG. 9(a), a plurality of resonant elements 2001 with same projection outlines are disposed on the substrate 100a, that is, dimensions of the projection outlines of the plurality of resonant elements 2001 are all the same. As shown in FIG. 9(b), dimensions of the plurality of resonant elements 2001 in a Z-axis direction are all d 71 .

[0095] In some implementations of this application, the plurality of resonant elements 2001 may be arrayed on the substrate 100a in a specific arrangement manner. For example, the plurality of resonant elements 2001 are sequentially arranged in a linear manner, or for another example, the plurality of resonant elements 2001 are sequentially arranged in a plurality of rows and columns, or for another example, the plurality of resonant elements 2001 are randomly arranged. This is not specifically limited in this application.

[0096] It may be understood that the resonant elements of the same outline type may not only be the resonant element 2001, but may alternatively be any resonant element in other resonant elements in this application. This is not specifically limited in this application.

[0097] In some embodiments of this application, as shown in FIG. 9(b), the substrate 100a is of an equal thickness in the Z-axis direction, that is, a thickness of any position on the surface of the substrate 100a in the Z-axis direction is a fixed value. For example, a thickness of any position on the surface of the substrate 100a in the Z-axis direction is d 71 .

[0098] Still refer to FIG. 9(b). It can be learned that, in some embodiments of this application, on the substrate 100a, the resonant element 2001 extends in a direction parallel to the Z-axis direction. That is, the resonant element 2001 penetrates two surfaces of the substrate 100a along the Z-axis direction.

[0099] FIG. 9(c) is a sectional view of the substrate 100a in the metasurface coating 30 along the section B-B in FIG. 9(a) according to some embodiments of this application. In some embodiments of this application, as shown in FIG. 9(c), on a substrate 100b, the resonant element 2001' extends along a direction intersecting with the Z-axis direction. That is, the resonant element 2001 penetrates the two surfaces of the substrate 100a along an inclined direction relative to the Z-axis direction.

[0100] Still refer to FIG. 9(b). It can be learned that, in some embodiments of this application, the substrate 100a extends along a same XOY plane.

[0101] FIG. 9(d) is a sectional view of the substrate 100a in the metasurface coating 30 along the section B-B in FIG. 9(a) according to some embodiments of this application. In some embodiments of this application, the substrate 100c is distributed in at least two XOY planes. As shown in FIG. 9(d), the substrate 100c includes a first part, a second part, a third part, a fourth part, and a fifth part, the first part, the third part, and the fifth part are distributed in an XOY plane, and the second part and the fourth part are distributed in another XOY plane. In some implementations, one XOY plane is parallel to another XOY plane. In some other implementations, the first part, the third part, and the fifth part are distributed on a curved surface, and the second part and the fourth part are distributed on another curved surface. This is not specifically limited in this application.

[0102] Still refer to FIG. 9(d). It can be learned that, in some implementations of this application, a position at which two adjacent parts are connected is located between the resonant element 2001 and a body of the substrate 100c, and the two adjacent parts may be connected in a staggered manner.

[0103] In some other alternative implementations of this application, a connecting position between the two adjacent parts is located on a substrate body, and the substrate body at the connecting position may be connected in a staggered manner or in a smooth transition manner. This is not specifically limited in this application.

[0104] In some embodiments of this application, a plurality of resonant elements are disposed on the substrate, and at least two of the plurality of resonant elements are different. That the at least two resonant elements are different means that at least one of all structure dimensions of the at least two resonant elements is different.

[0105] In some embodiments of this application, types of projection outlines of the at least two resonant elements are different.

[0106] FIG. 10(a) is a top view of a substrate 100d in the metasurface coating 30 according to some embodiments of this application. As shown in FIG. 10(a), a plurality of resonant elements disposed on the substrate 100d include resonant elements 2001 and resonant elements 2002.

[0107] Among the plurality of resonant elements on the substrate 100d, the resonant elements 2001 and the resonant elements 2002 are arranged in various manners on the substrate 100d. For example, the resonant elements 2001 and the resonant elements 2002 are arranged in a staggered manner, or for another example, the resonant elements 2001 are arranged in a clustered manner, and then the resonant elements 2002 are arranged in a clustered manner. This is not specifically limited in this application.

[0108] It may be understood that the resonant elements of at least two outline types may not only be the resonant element 2001 and the resonant element 2002, but also include at least two resonant elements of any other combination. This is not specifically limited in this application.

[0109] In some embodiments of this application, the types of the projection outlines of the at least two resonant elements are the same, but at least one structure dimension of the projection outlines of the at least two resonant elements is different.

[0110] In some embodiments of this application, the at least two resonant elements have different thicknesses.

[0111] FIG. 10(b) is a sectional view of a substrate 100e in the metasurface coating 30 along the section B-B in FIG. 9(a) according to some embodiments of this application. As shown in FIG. 10(b), the substrate 100e includes a first part, a second part, and a third part having different thickness dimensions. Thickness dimensions of the first part and the third part of the substrate 100e in the Z-axis direction are d 71 , and a dimension of the second part of the substrate 100a in the Z-axis direction is d 72 . Therefore, dimensions of resonant elements 2001 in the first part and the third part in the Z-axis direction are d 71 , and dimensions of resonant elements 2001" in the second part in the Z-axis direction are d 72 .

[0112] FIG. 10(c) is a sectional view of a substrate 100f in the metasurface coating 30 along the section B-B in FIG. 9(a) according to some embodiments of this application. As shown in FIG. 10(c), resonant elements 2001"'-1 are disposed on the substrate 100f, and dimensions of the resonant elements 2001"'-1 are uneven in the Z-axis direction. For example, the resonant element 2001"'-1 is disposed at a connecting position of two adjacent parts that are connected in a staggered manner.

[0113] In some embodiments of this application, the at least two resonant elements have different sectional shapes. Still refer to FIG. 10(c). It can be learned that a resonant element 2001"'-2 is disposed on the substrate 100f, and a sectional shape of the resonant element 2001"'-2 is a parallelogram.

[0114] In some embodiments of this application, in the metasurface coating 30, the substrate 100 specifically includes at least two substrates 100, and the at least two substrates 100 are stacked in a first direction. The first direction is a direction in which the radiation array 20 and the ground plate 10 are stacked.

[0115] FIG. 11(a) is a three-dimensional diagram of the array antenna 1 according to some embodiments of this application. FIG. 11(b) is an exploded view of the array antenna 1 according to some embodiments of this application. FIG. 12(a) is a sectional view of the array antenna 1 along a section C-C in FIG. 11(a) according to some embodiments of this application. FIG. 12(b) is a partial enlarged view of an area S 2 in FIG. 12(a).

[0116] As shown in FIG. 11(b) and FIG. 12(a), in some embodiments of this application, in the metasurface coating 30, the substrate 100 specifically includes a first substrate 100' and a second substrate 100", a hollowed-out first resonant element 200' is disposed on the first substrate 100', and a hollowed-out second resonant element 200" is disposed on the second substrate 100". The first substrate 100' and the second substrate 100" are stacked along the first direction. The following uses the array antenna 1 in FIG. 11(b) and FIG. 12(a) as an example to further describe the metasurface coating 30 in the array antenna 1.

[0117] It may be understood that an outline of the first resonant element 200' and an outline of the second resonant element 200" may be at least one of an "H" shape, a "U" shape, a "C" shape, an "O" shape, a "square" shape, an "X" shape, a "Y" shape, a "Z" shape, a "T" shape, and an "L" shape.

[0118] In some embodiments of this application, there are at least two first resonant elements 200', and there are at least two second resonant elements 200". An outline of each first resonant element 200' in the at least two first resonant elements 200' may be any one of an "H" shape, a "U" shape, a "C" shape, an "O" shape, a "square" shape, an "X" shape, a "Y" shape, a "Z" shape, a "T" shape, and an "L" shape, and an outline of each second resonant element 200" in the at least two second resonant elements 200" may be any one of an "H" shape, a "U" shape, a "C" shape, an "O" shape, a "square" shape, an "X" shape, a "Y" shape, a "Z" shape, a "T" shape, and an "L" shape. This is not specifically limited in this application.

[0119] In some embodiments of this application, the first substrate 100' and the second substrate 100" in the metasurface coating 30 are completely the same.

[0120] In some implementations of this application, structure dimensions of the first substrate 100' and the second substrate 100" are correspondingly the same, quantities and positions of the first resonant elements 200' on the first substrate 100' and the second resonant elements 200" on the second substrate 100" are the same, and the first resonant elements 200' and the second resonant elements 200" at a same relative position of the first substrate 100' and the second substrate 100" have same outlines and dimensions.

[0121] In some embodiments of this application, there are at least two substrates 100 in the metasurface coating 30, and the at least two substrates 100 are stacked. The at least two substrates 100 are completely the same. As shown in FIG. 13(a) and FIG. 13(b), the metasurface coating 30 includes two substrates 100a.

[0122] In some other embodiments of this application, structures of the first substrate 100' and the second substrate 100" in the metasurface coating 30 are different.

[0123] In some implementations of this application, at least one structure dimension of the first substrate 100' is different from that of the second substrate 100". For example, a thickness of the first substrate 100' is different from that of the second substrate 100".

[0124] For another example, a length of the first substrate 100' is different from that of the second substrate 100". For still another example, a width of the first substrate 100' is different from that of the second substrate 100".

[0125] In some other implementations of this application, quantities and / or positions of the first resonant elements 200' on the first substrate 100' and the second resonant elements 200" on the second substrate 100" are different.

[0126] In some other implementations of this application, the first resonant element 200' and the second resonant element 200" at relative positions corresponding to the first substrate 100' and the second substrate 100" have different outlines and / or dimensions.

[0127] In some other embodiments of this application, structure dimensions of the at least two substrates 100 are different.

[0128] In some implementations of this application, the at least two substrates 100 have different dimensions in a thickness direction, and / or the at least two substrates 100 have different dimensions in a length direction, and / or the at least two substrates 100 have different dimensions in a width direction.

[0129] In some implementations of this application, the at least two substrates are substrates of different types. For example, with reference to the foregoing accompanying drawings, the metasurface coating 30 includes any one of the substrate 100a and the substrate 100b, the substrate 100a and the substrate 100c, the substrate 100a and the substrate 100d, the substrate 100a and the substrate 100e, and the substrate 100a and the substrate 100f. This is not described in detail herein.

[0130] In some other embodiments of this application, layout positions of resonant elements on the at least two substrates 100 are different. As shown in FIG. 14(a), the metasurface coating 30 includes the substrate 100a and a substrate 100a', and a layout position of a resonant element 2001 on the substrate 100a is different from a layout position of a resonant element 2001 on the substrate 100a".

[0131] In some other embodiments of this application, quantities of resonant elements on the at least two substrates 100 are different. As shown in FIG. 14(b), the metasurface coating 30 includes the substrate 100a and a substrate 100a", a quantity of resonant elements 2001 on the substrate 100a is 12, and a quantity of resonant elements 2001 on the substrate 100a" is 13.

[0132] It may be understood that the implementations in which the structures of the first substrate 100' and the second substrate 100" are different are merely some examples, and another implementation in which the structures of the first substrate 100' and the second substrate 100" are different falls within the protection scope of this application. This is not specifically limited in this application.

[0133] In some embodiments of this application, a distance between two adjacent substrates 100 ranges from 3 mm to 7.5 mm. The distance between the two adjacent substrates 100 is a minimum distance between the two adjacent substrates 100, for example, d shown in FIG. 12(b). Specifically, in some embodiments of this application, a distance between two adjacent substrates 100 is 5 mm.

[0134] To further implement low sidelobe processing of the array antenna 1, continue to refer to FIG. 4(d) and FIG. 8(a) to FIG. 8(f). It can be learned that, in some embodiments of this application, the metasurface coating 30 further includes a wave-absorbing component 300. An orthographic projection of the wave-absorbing component 300 on the ground plate 10 is at least partially located in an orthographic projection of the resonant element 200 on the ground plate 10. For example, the wave-absorbing component 300 may be a chip resistor.

[0135] It may be understood that a dimension d 16 in FIG. 8(a) is a structure dimension of the wave-absorbing component 300. It may be understood that, a dimension of a relative position of the wave-absorbing component 300 relative to the resonant element 200 may be further marked in the figure. Because the wave-absorbing component 300 is arranged at a position on the right in the middle of the "H" shape, a related dimension of the relative position of the wave-absorbing component 300 relative to the resonant element 2001 is not described in detail herein.

[0136] It may be understood that a dimension d 26 in FIG. 8(b) is a structure dimension of the wave-absorbing component 300. A dimension d 27 is a related dimension of a relative position of the wave-absorbing component 300 relative to the resonant element 200.

[0137] It may be understood that, in FIG. 8(c), a dimension of a relative position of the wave-absorbing component 300 relative to the resonant element 200 may be further marked in the figure. Because the wave-absorbing component 300 is arranged at a position on the right in the middle of the "O" shape, the related dimension of the relative position of the wave-absorbing component 300 relative to the resonant element 200 is not described in detail herein.

[0138] The array antenna 1 may implement beam reconfiguration and adjust a pattern of the array antenna by adding a wave-absorbing material to the metasurface coating 30. In addition, the metasurface coating 30 may also be used in an existing array antenna loaded by a passive power divider, to correct a sidelobe level elevation phenomenon of the array antenna 1 caused by an error introduced by the passive power divider.

[0139] In some embodiments of this application, the metasurface coating 30 adjusts transmittance and a transmittance phase of an artificial electromagnetic material by optimizing a structure dimension of a material unit and a loss of a lossy component (for example, a resistance value of the chip resistor or a wave-absorbing rate of a wave-absorbing material), to equivalently adjust and control an excitation amplitude and phase of each radiation array element, thereby implementing low sidelobe processing of the array antenna 1. The metasurface coating 30 may also be used in an array antenna loaded by a power divider, to correct a sidelobe level elevation phenomenon caused by an error introduced by the power divider. In comparison with a conventional power divider design, the array antenna in this application has features such as a simple structure, a short research and development cycle, and a low cost.

[0140] In some embodiments of this application, the array antenna 1 is a specific structure shown in FIG. 11(a) to FIG. 12(b). In some implementations of this application, the metasurface coating 30 in the array antenna 1 includes at least two substrates 100, and each substrate 100 is periodically etched with an "H"-shaped slot. By way of optimizing a structure dimension of each "H"-shaped slot, electromagnetic waves transmitted by the radiation arrays 20 in the array antenna 1 have different transmittance and transmittance phases through action of respective slots. In this way, a sidelobe level of the antenna is reduced by performing vector superposition on patterns of the radiation array elements in a far-field region.

[0141] In some embodiments of this application, the array antenna 1 is a specific structure shown in FIG. 11(a) to FIG. 12(b). In some implementations of this application, the metasurface coating 30 in the array antenna 1 includes at least two substrates 100. Each substrate 100 is periodically etched with an "H"-shaped slot, and a wave-absorbing component 300 is added in the middle of the "H"-shaped slot of a lower-layer substrate 100. By way of properly selecting a resistance value of the wave-absorbing component 300 and optimizing a structure dimension of each "H"-shaped slot, electromagnetic waves transmitted by the radiation arrays 20 in the array antenna 1 have different transmittance and transmittance phases through action of respective slots. In this way, a sidelobe level of the array antenna is reduced by performing vector superposition on patterns of the radiation array elements in a far-field region.

[0142] In some embodiments of this application, a design scheme of the metasurface coating 30 in the array antenna 1 is related to a method for integrating an array antenna pattern. FIG. 15(a) shows a design scheme of the metasurface coating 30 in the array antenna 1 according to some embodiments of this application. The following describes the design scheme of the metasurface coating 30 in the array antenna 1 with reference to FIG. 15(a).

[0143] As shown in FIG. 15(a), the design scheme of the metasurface coating 30 in the array antenna 1 provided in this application specifically includes the following steps.

[0144] Box S1501: Obtain amplitude and phase distribution of each radiation array 20 based on a required pattern feature through pattern integration or algorithm optimization.

[0145] For example, to verify that the designed metasurface coating has a low sidelobe effect, according to a suppression requirement of completing a sidelobe level of -26 dB in a space angle from 20° to 90°, amplitude and phase distribution of excitation of a group of 12 radiation arrays 20 is provided through algorithm optimization, as shown in Table 1. Table 1Radiation array element sequence number123456789101112Amplitude0.70.70.81111110.710.7Phase-50000000000050

[0146] Box S1502: Calculate a transmittance coefficient and transmittance phase distribution of the metasurface coating 30 based on the amplitude and phase distribution of each radiation array 20. The transmittance coefficient is equal to an element amplitude, and a transmittance phase is equal to a radiation array element phase.

[0147] Box S1503: Adjust a physical dimension of the metasurface coating 30 and a loading resistance value through simulation optimization. It may be understood that a transmission coefficient and a transmission phase that are required by the array antenna are obtained through the physical dimension of the metasurface coating 30 and the loading resistance value.

[0148] The physical dimension of the metasurface coating 30 includes structure dimensions of the substrate 100 and the resonant element 200. The loading resistance value is determined by the wave-absorbing component 300.

[0149] In some embodiments of this application, excitation amplitude-phase distribution is linearly converted into an amplitude ratio of transmittance of an emergent electromagnetic wave and a phase difference of the emergent electromagnetic wave, and then each structure dimension and a resistance value of the metasurface coating 30 are reversely deduced.

[0150] To verify a low sidelobe processing effect of the array antenna 1 in this application, in some embodiments of this application, the optimized metasurface coating is placed right above a simplified symmetrical dipole element array, and a pattern is simulated and calculated by using (Ansoft High Frequency Structure Simulator, AHFSS) simulation software.

[0151] FIG. 15(b) is a simulation pattern of the array antenna 1 according to some embodiments of this application. A horizontal axis represents a phase of the array antenna 1, and a unit is °. A vertical axis represents an amplitude of the array antenna 1, and a unit is dB. The simulation pattern is obtained by performing simulation and calculation on the pattern by using the AHFSS simulation software. The metasurface coating 30 includes at least two substrates 100, and each substrate 100 is periodically etched with an "H"-shaped slot. A distance between two adjacent substrates 100 in the metasurface coating 30 is 5 mm. In FIG. 15(b), a curve L 1 represents a pattern of the array antenna 1 in this application, and a curve L 2 represents a pattern of an original array antenna 1. As shown in FIG. 15(b), it can be learned from a comparison between the curve L 1 and the curve L 2 that, in this application, the array antenna 1 added with the metasurface coating 30 has a low sidelobe effect; and in comparison with an existing uniform linear array, the array antenna in this application has a better sidelobe suppression effect in a specified area

[0152] To implement adjustability of the pattern of the array antenna 1, in some other application scenarios, the metasurface coating 30 may also be used with a reconfigurable material to implement a beam reconfiguration or beam phase scanning function. In other words, the wave-absorbing component 300 may be a component whose resistance value is adjustable. When the resistance value of the wave-absorbing component 300 changes, a pattern waveform of the array antenna 1 changes.

[0153] In some embodiments of this application, the wave-absorbing component 300 includes at least one of the following: a photosensitive resistor, a varistor, and a graphene material. It may be understood that the wave-absorbing component 300 may alternatively be made of another material. This is not specifically limited in this application.

[0154] In some implementations of this application, the wave-absorbing component 300 is a photosensitive resistor, and a resistance value of the wave-absorbing component 300 is adjusted by changing strength of light. In some other implementations of this application, the wave-absorbing component 300 is made of a graphene material, and a resistance value of the wave-absorbing component 300 is changed by using an external voltage.

[0155] In some embodiments of this application, an actual feeding amplitude and a phase value of each radiation array element are obtained by using an array analysis and integration method, and a fixed beam shape at a specific scanning angle is implemented by optimizing a slot structure and an initial state of an adjustable lossy material (a photosensitive resistor, a varistor, a graphene material, or the like). An external environment (such as light strength and an external voltage) of each resonant element 200 on the metasurface coating 30 is changed, so that an impedance value at a position where the resonant element 200 is located is also changed. Therefore, when a radiation field of each radiation array 20 passes through the metasurface coating 30, a transmittance coefficient is changed. Therefore, a beam shape of the array pattern may be dynamically adjusted.

[0156] In some embodiments of this application, the array antenna 1 is a specific structure shown in FIG. 11(a) to FIG. 12(b). In some implementations of this application, the metasurface coating 30 in the array antenna 1 includes at least two substrates 100, and each substrate 100 is periodically etched with an "H"-shaped slot. A wave-absorbing component 300 is added in the middle of the "H"-shaped slot of a lower-layer substrate 100. The wave-absorbing component 300 may be an adjustable lossy material. By way of properly selecting each resistance value and optimizing a structure dimension of each "H"-shaped slot, electromagnetic waves transmitted by the radiation arrays 20 in the array antenna 1 have different transmittance and transmittance phases through action of respective slots and chip resistors. In this way, a sidelobe level of the antenna is reduced by performing vector superposition on patterns of the radiation array elements in a far-field region.

[0157] FIG. 16 is a simulation pattern of the array antenna 1 according to some embodiments of this application. A horizontal axis represents a phase of the array antenna 1, and a unit is °. A vertical axis represents an amplitude of the array antenna 1, and a unit is dB. FIG. 16 shows an effect diagram of implementing a reconfigurable technology of an array pattern under dynamic adjustment of resistance values of resonant elements in the metasurface coating by an adjustable lossy material. A curve L 3 is a pattern of a dipole array in which a resistance value of each resonant element 200 is adjusted to be in a state 1 after the metasurface coating 30 is added. In this case, a sidelobe level of -28 dB or less within -20° to -75° may be implemented. A curve L 4 is a pattern of the dipole array in which a resistance value of each resonant element 200 is adjusted to be in a state 2 after the metasurface coating is added. In this case, a pattern of a sidelobe null within -20° to -50° may be implemented. To amplify a wanted signal and suppress an interference signal to the greatest extent, it is most intuitive for the sidelobe null to align the main lobe with an incident direction of the wanted signal, and to align a lowest gain point (that is, a null) in the pattern with an incident direction of the interference signal.

[0158] In some embodiments of this application, a specific resistance value of each resonant element 200 in each state needs to be separately designed and optimized based on a required pattern effect. This is not specifically limited in this application.

[0159] For the array antenna 1, the adjustable lossy material is introduced to the metasurface coating 30, so that the radiation pattern of the array antenna 1 has a beam reconfiguration characteristic while implementing a low sidelobe function. The array antenna 1 has a simple structure and a large degree of freedom in design.

[0160] This application further provides a metasurface coating 30. The metasurface coating 30 includes a substrate 100 and a resonant element 200 disposed on the substrate 100.

[0161] This application further provides a radome assembly (not marked). The radome assembly includes a radome 40 and a metasurface coating 30. The metasurface coating 30 includes a substrate 100 and a resonant element 200 disposed on the substrate 100.

[0162] In addition, the technical solutions in this application are highly integrated, and design is liberalized, so that beamforming of any beam can be implemented. Certainly, low-delay switching between a plurality of beams may be implemented in combination with a popular reconfigurable technology.

[0163] It should be noted that, in this specification, similar reference numerals and letters in the following accompanying drawings represent similar items. Therefore, once an item is defined in an accompanying drawing, the item does not need to be further defined or interpreted in the following accompanying drawings.

[0164] The foregoing describes implementations of this application in specific embodiments, and other advantages and effects of this application may be readily understood by a person skilled in the art from content disclosed in this specification. Although this application is described with reference to some embodiments, it does not mean that a feature of this application is limited only to this implementation. On the contrary, a purpose of describing this application with reference to an implementation is to cover another option or modification that may be derived based on claims of this application. To provide an in-depth understanding of this application, the following descriptions include a plurality of specific details. This application may be alternatively implemented without using these details. In addition, to avoid confusion or blurring a focus of this application, some specific details are omitted from the description. It should be noted that embodiments in this application and features in embodiments may be mutually combined in the case of no conflict.

[0165] In the descriptions of this application, it should be noted that, directions or position relationships indicated by terms such as "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", "a circumferential direction", "a radical direction", and "an axial direction" are based on the directions or position relationships shown in the accompanying drawings, and are merely intended to describe this application and simplify the descriptions, but are not intended to indicate or imply that an indicated apparatus or element needs to have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on this application.

[0166] In descriptions of this application, it should be noted that unless otherwise explicitly specified and limited, terms such as "dispose", "mount", "connect", and "attach" should be understood in a broad sense. For example, such terms may indicate a fixed connection, a detachable connection, or an integral connection, may indicate a mechanical connection or an electrical connection, and may indicate a direct connection, an indirect connection through an intermediate medium, or an internal communication between two elements. For a person of ordinary skill in the art, a specific meaning of the foregoing terms in this application may be understood based on a specific situation.

[0167] It is clearly that a person skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. This application is intended to cover these modifications and variations of this application provided that they fall within the scope of protection defined by the following claims and their equivalent technologies.

Claims

1. An array antenna (1), wherein the array antenna (1) comprises: a radiation array (20), wherein the radiation array (20) comprises at least two radiation array elements; and a metasurface coating (30), wherein the metasurface coating (30) comprises a substrate (100) and a resonant element (200) disposed on the substrate (100), the metasurface coating (30) is coated on a radiation end of the radiation array element, and a surface of the substrate (100) intersects a radiation direction of the radiation array (20).

2. The array antenna (1) according to claim 1, wherein the substrate (100) is configured to adjust transmittance of an electromagnetic wave radiated by the radiation array (20), and the resonant element (200) is configured to adjust a transmission phase of the electromagnetic wave radiated by the radiation array (20).

3. The array antenna (1) according to claim 1 or 2, wherein an outline of the resonant element (200) comprises at least one of the following: an "H" type, a "U" shape, a "C" shape, an "O" shape, a "square" shape, an "X" shape, a "Y" shape, a "Z" shape, a "T" shape, and an "L" shape.

4. The array antenna (1) according to any one of claims 1 to 3, wherein in the metasurface coating (30), the substrate (100) specifically comprises at least two substrates (100), and the at least two substrates (100) are stacked along the radiation direction.

5. The array antenna (1) according to claim 4, wherein a distance between two adjacent substrates (100) ranges from 3 mm to 7.5 mm, and the distance between the two adjacent substrates (100) is a minimum distance between the two adjacent substrates (100).

6. The array antenna (1) according to claim 5, wherein the distance between the two adjacent substrates (100) is 5 mm.

7. The array antenna (1) according to any one of claims 1 to 6, wherein the metasurface coating (30) further comprises: a wave-absorbing component (300), wherein an orthographic projection of the wave-absorbing component (300) on the substrate (100) is at least partially located in an orthographic projection of the resonant element (200) on the substrate (100).

8. The array antenna (1) according to claim 7, wherein the wave-absorbing component (300) comprises at least one of the following: a photosensitive resistor, a varistor, and a graphene material.

9. The array antenna (1) according to any one of claims 1 to 8, wherein the array antenna (1) further comprises: a ground plate (10), wherein the ground plate (10) is provided with a first surface made of a conductive material, and the radiation array (20) is disposed on the first surface of the ground plate (10).

10. The array antenna (1) according to claim 9, wherein the antenna (1) further comprises a radome (40), the radome (40) and the ground plate (10) jointly form an accommodating cavity (50), the radiation array (20) is located within the accommodating cavity (50), and a layout position of the metasurface coating (30) relative to the radome (40) comprises at least one of the following: the metasurface coating (30) is located within the accommodating cavity (50); or the metasurface coating (30) is located outside the accommodating cavity (50); or a mounting cavity (60) is formed in the radome (40), the mounting cavity (60) is located on a side that is of the radiation array (20) and that faces away from the ground plate (10), and the metasurface coating (30) is disposed in the mounting cavity (60).

11. A metasurface coating (30), wherein the metasurface coating (30) comprises a substrate (100) and a resonant element (200) disposed on the substrate (100).

12. A radome assembly, wherein the radome assembly comprises: a radome (40); and a metasurface coating (30), wherein the metasurface coating (30) comprises a substrate (100) and a resonant element (200) disposed on the substrate (100).

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