Antenna unit and antenna array

Abstract

The invention provides an antenna unit, which comprises radiators, and is characterized in that the radiators comprise a first radiator and a second radiator, and the first radiator and the second radiator are arranged at intervals along the thickness direction of the antenna unit; the first radiator comprises a plurality of first patch units which are uniformly distributed, and the second radiator comprises a plurality of second patch units which are uniformly distributed; the projection of the first patch unit on the plane of the antenna unit and the projection of at least one second patch unit on the plane of the antenna unit have an overlapped part, and the plane of the antenna unit is a plane perpendicular to the thickness direction of the antenna unit. The invention also provides an antenna array.

Description

Technical Field

[0001] The present disclosure relates to the field of antenna technology, and in particular to an antenna unit and an antenna array. Background Art

[0002] With the rapid development of mobile communication technology, 5G wireless communication systems have increasingly higher requirements for antenna performance. The metasurface antenna uses a periodic structure of limited size as the main radiator of the antenna, which is directly located in the inductive near-field area of ​​the feed structure. It is a two-dimensional low-profile integrated antenna. It has the advantages of simple structure, easy manufacturing, low cost, and low profile when applied to millimeter-wave communications. Since it can work in coordination with two or more modes through aperture expansion, metamaterial antennas provide a low-profile broadband solution that is more advantageous than traditional laminated patches, and are a good choice for 5G millimeter-wave packaged antenna applications. However, this antenna form that uses aperture expansion to increase multi-mode collaborative radiation usually also means a larger metamaterial structure size. At a low profile, its width is even close to one working wavelength, which greatly limits its application in antenna arrays with low sidelobe level requirements.

[0003] The current dual-polarization metasurface antennas can usually only take into account the realization of two polarizations and cannot be further miniaturized to meet the array requirements. At the same time, the dual-polarization application of metasurface antennas will also face the lack of design freedom when matching broadband standing waves. Therefore, there are still many difficulties in realizing the application of metasurface antennas in low-profile and low-sidelobe level dual-polarization arrays. Summary of the invention

[0004] The embodiments of the present disclosure provide an antenna unit and an antenna array.

[0005] In a first aspect, an embodiment of the present disclosure provides an antenna unit, comprising a radiator, wherein the radiator comprises a first radiator and a second radiator, and the first radiator and the second radiator are arranged at intervals along the thickness direction of the antenna unit; the first radiator comprises a plurality of uniformly distributed first patch units, and the second radiator comprises a plurality of uniformly distributed second patch units; a projection of the first patch unit on the plane of the antenna unit has an overlapping part with a projection of at least one of the second patch units on the plane of the antenna unit, wherein the plane of the antenna unit is a plane perpendicular to the thickness direction of the antenna unit.

[0006] In a second aspect, an embodiment of the present disclosure provides an antenna array, wherein the antenna array is composed of an array consisting of a plurality of antenna units, and the antenna units are the antenna units described in the first aspect of the embodiment of the present disclosure.

[0007] In the embodiment of the present disclosure, the first radiator and the second radiator in the antenna unit constitute a double-layer metasurface structure, a gap capacitor is formed between the first patch units of the same layer in the first radiator, and a gap capacitor is formed between the second patch units of the same layer in the second radiator; the projection of the first patch unit on the plane of the antenna unit and the projection of at least one second patch unit on the plane of the antenna unit have an overlapping part, and an interlayer capacitor is formed between the first patch unit and the second patch unit, thereby reducing the size of the metasurface and meeting the application of low sidelobe level arrays; the interlayer spacing between the first radiator and the second radiator is small, so that the antenna profile of the metasurface antenna unit in the embodiment of the present disclosure is low, which is beneficial to reducing the thickness of the dielectric layer while meeting the antenna working bandwidth, thereby improving the system integration; in addition, the multi-layer structure of the antenna unit in the embodiment of the present disclosure can be applied to multi-layer printed circuit board processing, which is beneficial to reducing manufacturing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a schematic diagram of an antenna unit in an embodiment of the present disclosure;

[0009] Figure 2 is a schematic diagram of a first radiator in an antenna unit in an embodiment of the present disclosure;

[0010] Figure 3 is a schematic diagram of a second radiator in an antenna unit in an embodiment of the present disclosure;

[0011] Figure 4 is a schematic diagram of a reflection surface and a feeder in an embodiment of the present disclosure;

[0012] Figure 5 is a schematic diagram of an antenna array in an embodiment of the present disclosure;

[0013] Figure 6 is a simulation schematic diagram of a dual-polarized antenna in an embodiment of the present disclosure without a non-radiative matching patch array;

[0014] Figure 7 It is a simulation schematic diagram of a dual-polarized antenna with a non-radiative matching patch array in an embodiment of the present disclosure;

[0015] Figure 8 It is a schematic diagram of antenna array beam scanning in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0016] In order to enable those skilled in the art to better understand the technical solution of the present disclosure, the antenna unit and antenna array provided by the present disclosure are described in detail below with reference to the accompanying drawings.

[0017] Example embodiments will be described more fully below with reference to the accompanying drawings, but the example embodiments may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. On the contrary, the purpose of providing these embodiments is to make the present disclosure thorough and complete and to enable those skilled in the art to fully understand the scope of the present disclosure.

[0018] In the absence of conflict, the various embodiments of the present disclosure and the various features therein may be combined with each other.

[0019] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0020] The terms used herein are only used to describe specific embodiments and are not intended to limit the present disclosure. As used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms, unless the context clearly indicates otherwise. It will also be understood that when the terms "comprising" and / or "made of" are used in this specification, the presence of the features, wholes, steps, operations, elements and / or components is specified, but the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or groups thereof is not excluded.

[0021] The embodiments described herein may be described with reference to plan views and / or cross-sectional views by means of idealized schematic diagrams of the present disclosure. Therefore, the example illustrations may be modified according to manufacturing techniques and / or tolerances. Therefore, the embodiments are not limited to the embodiments shown in the accompanying drawings, but include modifications of the configurations formed based on the manufacturing process. Therefore, the regions illustrated in the accompanying drawings have schematic properties, and the shapes of the regions shown in the figures illustrate the specific shapes of the regions of the elements, but are not intended to be limiting.

[0022] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted as having an idealized or overly formal meaning unless explicitly defined as such herein.

[0023] First, refer to Figure 1 , Figure 2 , Figure 3An embodiment of the present disclosure provides an antenna unit, including a radiator 1, wherein the radiator 1 includes a first radiator 11 and a second radiator 12, and the first radiator 11 and the second radiator 12 are arranged at intervals along the thickness direction of the antenna unit; the first radiator 11 includes a plurality of uniformly distributed first patch units 111, and the second radiator 12 includes a plurality of uniformly distributed second patch units 121; a projection of the first patch unit 111 on the plane of the antenna unit has an overlapping portion with a projection of at least one second patch unit 121 on the plane of the antenna unit, wherein the plane of the antenna unit is a plane perpendicular to the thickness direction of the antenna unit.

[0024] In the embodiment of the present disclosure, the antenna unit is a low-profile dual-polarization metasurface antenna unit, and the radiator 1 in the antenna unit is a double-layer metasurface structure composed of a first radiator 11 and a second radiator 12, wherein the first patch unit 111 is a metasurface unit, and the second patch unit 121 is also a metasurface unit.

[0025] In the embodiment of the present disclosure, a plurality of uniformly distributed first patch units 111 constitute a first radiator 11, wherein the uniform distribution of the first patch units 111 means that the plurality of first patch units 111 are spaced apart, and the spacings between adjacent first patch units 111 are equal; a plurality of uniformly distributed second patch units 121 constitute a first radiator 12, wherein the uniform distribution of the second patch units 121 means that the plurality of second patch units 121 are spaced apart, and the spacings between adjacent second patch units 121 are equal.

[0026] In the embodiment of the present disclosure, the plane of the antenna unit is perpendicular to the thickness direction of the antenna unit, which is not limited to strict perpendicularity in a geometric sense. As long as there is an angle between the plane of the antenna unit and the thickness direction of the antenna unit, the relationship between the plane of the antenna unit and the thickness direction of the antenna unit in the embodiment of the present disclosure is satisfied.

[0027] In the embodiment of the present disclosure, gap capacitance is formed between the first patch units 111 of the same layer, and gap capacitance is formed between the second patch units 121 of the same layer; since the projection of the first patch unit 111 on the antenna unit plane overlaps with the projection of at least one second patch unit 121 on the antenna unit plane, an interlayer capacitance is formed between the first patch unit 111 and the second patch unit 121, thereby reducing the size of the metasurface, for example, less than 0.5×0.5 free space wavelengths, such as less than 0.3×0.3 free space wavelengths, to meet the application of low sidelobe level arrays; the interlayer spacing between the first radiator 11 and the second radiator 12 is small, so that the antenna profile of the metasurface antenna unit in the embodiment of the present disclosure is low, for example, 0.02 to 0.1 free space wavelengths, such as 0.06 free space wavelengths, which is conducive to reducing the thickness of the dielectric layer while meeting the antenna working bandwidth, thereby improving the system integration; in addition, the multilayer structure of the antenna unit in the embodiment of the present disclosure can be suitable for multilayer printed circuit board (PCB, Printed Circuit Board) processing, which is conducive to reducing manufacturing costs.

[0028] In some embodiments, reference Figure 1 The antenna unit also includes a supporting dielectric layer 4, a supporting dielectric layer 5, and a supporting dielectric layer 6.

[0029] In the embodiment of the present disclosure, the number of the first patch units 111 constituting the first radiator 11 may be equal to or unequal to the number of the second patch units 121 constituting the second radiator 12. The embodiment of the present disclosure does not specifically limit this.

[0030] In some embodiments, reference Figure 2 , Figure 3 The first radiator 11 is an array composed of M×M first patch units 111, and the spacing between adjacent first patch units 111 is equal; the second radiator 12 is an array composed of N×N second patch units 121, and the spacing between adjacent second patch units 121 is equal; wherein M and N are positive integers not less than 2, M=N; the spacing between the first patch units 111 is equal to the spacing between the second patch units 121.

[0031] In the embodiment of the present disclosure, the spacing between adjacent first patch units 111 is equal, the spacing between adjacent second patch units 121 is equal, and the spacing between the first patch units 111 and the spacing between the second patch units 121 are equal, which is conducive to enabling the antenna unit to support dual-polarization operation.

[0032] In the embodiment of the present disclosure, the number of the first patch units 111 constituting the first radiator 11 and the size of the second patch units 121 constituting the second radiator 12 may be the same or different. The embodiment of the present disclosure does not specifically limit this.

[0033] In some embodiments, multiple first patch units 111 correspond one-to-one to multiple second patch units 121, the size of the first patch unit 111 is consistent with the size of the second patch unit 121, and the projection of the first patch unit 111 on the antenna unit plane overlaps with the projection of the corresponding second patch unit 121 on the antenna unit plane.

[0034] In some embodiments, the projection of the first patch element 111 on the antenna element plane coincides with the projection of the corresponding second patch element 121 on the antenna element plane.

[0035] In the embodiment of the present disclosure, multiple first patch units 111 correspond one-to-one to multiple second patch units 121, and the projection of the first patch unit 111 on the antenna unit plane coincides with the projection of the corresponding second patch unit 121 on the antenna unit plane, which is beneficial to increase the interlayer capacitance between the first patch unit 111 and the second patch unit 121, thereby helping to reduce the size of the metasurface and meet the needs of low sidelobe level array applications.

[0036] The embodiment of the present disclosure does not specifically limit the specific structure of the second patch unit.

[0037] In some embodiments, reference Figure 3 , the second patch unit 121 is a subarray consisting of l×l second sub-patch units 121a, and the polarization direction of the second sub-patch unit 121a is the same as the polarization direction of the first patch unit, where l is an integer.

[0038] In the embodiment of the present disclosure, the center of the second patch unit 121 is consistent with the center of the corresponding first patch unit 111 in the thickness direction of the antenna unit; accordingly, the array center of the subarray composed of l×l second sub-patch units 121a is consistent with the center of the corresponding first patch unit 121 in the thickness direction of the antenna unit.

[0039] In the embodiment of the present disclosure, the second patch unit 121 is formed by a sub-array consisting of l×l second sub-patch units 121a, which can increase the gap capacitance between the second patch units 121, thereby facilitating the miniaturization of the metasurface structure.

[0040] In some embodiments, the first radiator is an array composed of M×M first patch units, and the spacing between adjacent first patch units is equal; the second radiator is an array composed of N×N second patch units, and the spacing between adjacent second patch units is equal; wherein M and N are positive integers not less than 2, and M≠N.

[0041] In some embodiments, the size of the first patch unit is not consistent with the size of the second patch unit.

[0042] In the embodiment of the present disclosure, the shape of the first patch unit is uniform and symmetrical, and the shape of the second patch unit is uniform and symmetrical, which is conducive to the antenna unit to achieve dual-polarization operation.

[0043] The embodiments of the present disclosure do not specifically limit the specific shapes of the first patch unit and the second patch unit.

[0044] In some embodiments, the shape of the first patch unit is one of a square, a rectangle, and a diamond, and the shape of the second patch unit is one of a square, a rectangle, and a diamond.

[0045] In some embodiments, reference Figure 1 , Figure 2 The antenna unit also includes a non-radiative matching patch array composed of multiple non-radiative matching patches 7. In the non-radiative matching patch array, the non-radiative matching patches 7 are arranged along the polarization direction of the first radiator 11, and the side lengths of the non-radiative matching patches 7 arranged along the same polarization direction are equal; the projection of the non-radiative matching patch array on the plane of the antenna unit has no overlapping part with the projection of the first radiator on the plane of the antenna unit.

[0046] In some embodiments, Figure 1 , Figure 2 As shown, the non-radiative matching patch array is arranged at the edge of the antenna element.

[0047] In some embodiments, the non-radiative matching patch array and the first radiator are arranged in the same layer; or the non-radiative matching patch array and the first radiator are arranged in different layers.

[0048] In some embodiments, when the non-radiative matching patch array and the first radiator are arranged in different layers, the non-radiative matching patch array is arranged in a layer closer to the first radiator.

[0049] In the embodiment of the present disclosure, one or more layers of non-radiative matching patch arrays may be provided in the antenna unit, and the embodiment of the present disclosure does not specifically limit this.

[0050] In the disclosed embodiment, the polarization direction of the non-radiative matching patch array is the same as the polarization direction of the radiator 1, which can increase the design freedom of the low-profile antenna and improve the standing wave of the dual-polarized antenna, which is conducive to achieving better impedance matching for both polarizations.

[0051] In some embodiments, reference Figure 1 , Figure 4 The antenna unit also includes a reflecting surface 2 and a feed line 3. The reflecting surface 2 includes a first metal floor 21 and a second metal floor 22. The first metal floor 21 is arranged on a side of the feed line 3 close to the radiator 1, and the second metal floor 22 is arranged on a side of the feed line 3 away from the radiator 1. The first metal floor 21 and the second metal floor 22 are connected through an interconnection via 23, and a gap 24 is arranged on the first metal floor 21.

[0052] In the disclosed embodiment, multiple resonance modes can be realized by combining a resonant gap with a double-layer metasurface structure, which is beneficial for realizing broadband characteristics with a low profile.

[0053] The embodiment of the present disclosure does not specifically limit the shape of the gap 24. For example, the gap may be a cross-shaped gap or an I-shaped gap; wherein the I-shaped gap may also be referred to as an H-shaped gap.

[0054] For example, refer to Figure 4 , the gap 24 includes a first gap and a second gap; the first gap is composed of a connected first sub-gap 2411 and at least one second sub-gap 2412, and the extension direction of the first sub-gap 2411 intersects with the extension direction of the second sub-gap 2412; the second gap is composed of a connected third sub-gap 2421 and at least one fourth sub-gap 2422, and the extension direction of the third sub-gap 2421 intersects with the extension direction of the fourth sub-gap 2422.

[0055] In some embodiments, the gap 24 is a pair of H-shaped gaps arranged in a T-shaped manner. Figure 4, the gap 24 includes a first gap and a second gap; the first gap is composed of a connected first sub-gap 2411 and two second sub-gap 2412, the extension direction of the first sub-gap 2411 intersects with the extension direction of the second sub-gap 2412, and the two second sub-gap 2412 are respectively arranged at the two ends of the first sub-gap 2411; the second gap is composed of a connected third sub-gap 2421 and two fourth sub-gap 2422, the extension direction of the third sub-gap 2421 intersects with the extension direction of the fourth sub-gap 2422, and the two fourth sub-gap 2422 are respectively arranged at the two ends of the third sub-gap 2421; the extension direction of the first sub-gap 2411 intersects with the extension direction of the third sub-gap 2421, and the extension direction of the second sub-gap 2412 intersects with the extension direction of the fourth sub-gap 2422.

[0056] In some embodiments, reference Figure 4 The feed line 3 is composed of a strip line loaded with tuning branches, and the feed line 3 corresponds to the gap 24 on the reflecting surface 2.

[0057] In the disclosed embodiment, the feed line 3 is composed of a strip line loaded with tuning branches, which can increase the design freedom of the dual-polarization antenna and has high polarization isolation characteristics, which is conducive to better designing a broadband matching feeding network.

[0058] In some embodiments, reference Figure 4 , the feed line 3 includes a first feed line corresponding to the first slot and a second feed line corresponding to the second slot; the extension direction of the strip line of the first feed line intersects with the extension direction of the first sub-slot 2411, and the strip line of the second feed line intersects with the extension direction of the third sub-slot 2421; the projection of the first feed line on the antenna unit plane has an overlapping part with the projection of the first sub-slot 2411 on the antenna unit plane, and the projection of the second feed line on the antenna unit plane has an overlapping part with the projection of the third sub-slot 2412 on the antenna unit plane.

[0059] In the disclosed embodiment, the feed line 3 is composed of a strip line loaded with tuning branches, which can increase the design freedom of the dual-polarization antenna and have high polarization isolation characteristics.

[0060] In the disclosed embodiment, the gap 24 on the first metal floor 21 is a resonant gap. The gap 24 combined with the radiator 1 of the double-layer metasurface structure and the feeder loaded with tuning branches can realize multiple resonant modes, which is conducive to obtaining broadband characteristics with a low profile.

[0061] In the embodiment of the present disclosure, a feed line loaded with tuning branches is used to excite a metasurface structure through an H-shaped slot arranged in a T-shape, so that the design freedom of the dual-polarized antenna can be increased while having high polarization isolation characteristics.

[0062] In the disclosed embodiment, Figures 1 to 4 When the dual-polarized antenna shown is in operation, the polarization port outputs a radio frequency signal, which is transmitted through a feeder 3 composed of a strip line loaded with tuning branches, coupled to a radiator 1 composed of a first radiator 11 and a second radiator 12 through a slot 24 to generate resonance, and finally outputs a radiation signal.

[0063] Second, refer to Figure 5 An embodiment of the present disclosure provides an antenna array, which is composed of an array composed of multiple antenna units, and the antenna unit is the antenna unit described in the first aspect of the embodiment of the present disclosure.

[0064] In some embodiments, Figure 5 As shown, the antenna array is an array composed of 8×8 antenna units.

[0065] In some embodiments, the center distance between adjacent antenna units is 0.3-1 free space wavelength. For example, the center distance between adjacent antenna units is 0.5 free space wavelength.

[0066] In order to enable those skilled in the art to more clearly understand the technical solutions provided by the embodiments of the present disclosure, the technical solutions provided by the embodiments of the present disclosure are described in detail below through specific embodiments:

[0067] Embodiment 1

[0068] This embodiment provides a low-profile dual-polarization metasurface antenna unit, which consists of a radiator, a reflector, and a feeder. The radiator is composed of a double-layer metasurface structure that supports dual-polarization operation; the reflector is composed of a metal plate with two orthogonal polarization slots; and the feeder is composed of two groups of strip lines loaded with tuning branches.

[0069] The interlayer spacing of the double-layer metasurface structure of the radiator of the antenna unit is small. In the case of low profile, the size of the metasurface can be effectively reduced by means of the gap capacitance between the metasurface periodic units (patch units) in the same layer and the interlayer capacitance formed by the overlapping surface of the double-layer metasurface in the thickness direction of the antenna unit. At the same time, the double-layer metasurface structure is uniform and symmetrical, supporting dual-polarization operation.

[0070] The feed line of the antenna unit adopts stripline loading tuning branches, which increases the design freedom of the dual-polarized antenna compared with the existing direct stripline feeding scheme, and is conducive to further realizing broadband matching of the feeding structure.

[0071] Optionally, the antenna unit is also provided with a non-radiating matching patch array with the same polarization direction as the radiator, which can increase the design freedom of the low-profile antenna and further improve the standing wave of the dual-polarized antenna, which is conducive to achieving better impedance matching for both polarizations.

[0072] The antenna rectification formed by the antenna unit provided in this embodiment can meet the application of good low side lobe level.

[0073] Embodiment 2

[0074] Reference Figure 1 In this embodiment, the antenna unit includes a first radiator 11, a second radiator 12, a non-radiating matching patch array composed of a non-radiating matching patch 7, a first metal floor 21 with a gap 24, a feeder 3, and a second metal floor 22. The antenna unit also includes a supporting dielectric layer 4, a supporting dielectric layer 5, and a supporting dielectric layer 6. The first metal floor 21 and the second metal floor 22 are connected through an interconnection via 23.

[0075] Reference Figure 2 In this embodiment, the first radiator 11 has a uniform and symmetrical structure, and is composed of an array of 3×3 first patch units 111 arranged periodically, and the spacing between adjacent first patch units 111 is equal; the non-radiative matching patch array is arranged in the same layer as the first radiator 11, and the non-radiative matching patches 7 in the non-radiative matching patch array are arranged along the dual polarization direction of the first radiator 11, and the side lengths of the non-radiative matching patches 7 in the same polarization direction are equal.

[0076] Reference Figure 3 In this embodiment, the second radiator 12 has a uniform and symmetrical structure, and is composed of an array of 3×3 second patch units 121 arranged periodically. Each second patch unit 121 is composed of a subarray composed of 2×2 second sub-patch units 121a. The spacing between adjacent second patch units 121 is equal, and the spacing between adjacent second patch units 121 is equal to the spacing between adjacent first patch units 111. The side length of the second sub-patch unit 121a is half the side length of the first patch unit 111, and the polarization direction and array center are consistent. The projection of the first radiator 11 on the antenna unit plane overlaps with the projection of the second radiator 12 on the antenna unit plane, which can increase the interlayer capacitance between the first radiator 11 and the second radiator 12, the gap capacitance between the first patch units 111 in the first radiator 11, and the gap capacitance between the second sub-patches 121a in the second radiator 12, thereby realizing the miniaturization of the antenna unit, and then realizing the miniaturization of the metasurface structure.

[0077] Reference Figure 4In this embodiment, the first metal floor 21 with a slot 24 is used as a reflector of the antenna radiator, and the dual-polarized electromagnetic waves are coupled to the antenna radiator through the H-shaped slots arranged in a T-shape. The feeder 3 is two sets of orthogonal metal strip lines, and is loaded with tuning branches at the same time, which increases the design freedom compared to a simple strip feeder, and is conducive to better designing a broadband matching feeding network. The slot 24 is a resonant slot. The slot 24 is combined with the first radiator 11, the second radiator 12, and the feeder 3 loaded with tuning branches to achieve multiple resonant modes, which is conducive to achieving broadband characteristics with a low profile.

[0078] Reference Figure 5 In this embodiment, an antenna array is composed of 8×8 antenna units, the center spacing of each antenna unit in the antenna array is 0.5 free wavelength, and a non-radiative matching patch array is arranged in the antenna unit.

[0079] Figure 6 This is a simulation diagram of the dual-polarized antenna in this embodiment without a non-radiative matching patch array. Under the condition that the cross-sectional height is 0.06 free space wavelength, both polarizations achieve a relative bandwidth greater than 25%. At the same time, the isolation between the two polarization ports is greater than 30dB within the band.

[0080] Figure 7 The simulation diagram of the dual-polarized antenna in this embodiment with a non-radiative matching patch array is shown. Under the condition of a profile height of 0.06 free space wavelength, both polarizations achieve a relative bandwidth greater than 25%, and the port isolation of the two polarizations is greater than 30 dB in the band. Due to the non-radiative matching patch array, the dual-polarized antenna is given an additional degree of freedom to optimize its impedance matching, and the in-band standing waves of both polarizations are optimized by more than 5 dB, achieving better standing wave characteristics.

[0081] exist Figure 6 , Figure 7 In the figure, S parameter refers to scattering parameter, which is an important parameter in microwave transmission. S11 is the input reflection coefficient, that is, input return loss; S12 is the reverse transmission coefficient, that is, isolation; S21 is the forward transmission coefficient, that is, gain.

[0082] Figure 8 Schematic diagram of antenna array beam scanning in this embodiment. The antenna array beam does not produce obvious side lobes within the range of ±60°, and the gain decreases by less than 3dB when scanning at ±45°, which has good scanning characteristics.

[0083] In summary, the technical effects achieved by this embodiment are as follows:

[0084] (1) Metasurface antenna units and antenna arrays support dual-polarization operation;

[0085] (2) Using a feed line with tuning branches and an H-shaped slot excitation metasurface structure arranged in a T-shape, the design freedom of the dual-polarization antenna is increased, while having high polarization isolation characteristics;

[0086] (3) The use of resonant slots combined with a double-layer metasurface structure and a feed line loaded with branches to achieve multiple resonant modes is beneficial for achieving broadband characteristics with a low profile.

[0087] (4) The metasurface antenna unit can use multiple non-radiative matching patches to participate in matching, effectively improving the antenna standing wave;

[0088] (5) Using a double-layer metasurface with a small interlayer spacing to design antenna radiators, effectively reducing the physical size of the metasurface structure at a low profile (e.g., less than 0.3x0.3 free space wavelengths) to meet low sidelobe level array applications;

[0089] (6) The metasurface antenna has a low profile (e.g., 0.06 free space wavelength), which helps to reduce the thickness of the dielectric layer while meeting the working bandwidth and improving system integration;

[0090] (7) Metasurface antenna units and antenna arrays are suitable for multi-layer PCB processing and have low cost.

[0091] Embodiment 3

[0092] This embodiment is an alternative solution based on the second embodiment:

[0093] (1) The first radiator is an array consisting of M×M first patch units, and the second radiator is an array consisting of N×N second patch units, where M and N are positive integers not less than 2, wherein M may be equal to N or may not be equal to N.

[0094] (2) The shapes of the first patch unit and the second patch unit include but are not limited to square, rectangle, diamond and other uniform and symmetrical shapes.

[0095] (3) The sizes of the first patch unit and the second patch unit are not required to be strictly consistent. The interlayer spacing between the first radiator and the second radiator is small enough to achieve miniaturization of the metasurface structure.

[0096] (4) The non-radiative matching patch array can be arranged in the same layer or a layer close to the first radiator, and a single layer or multiple layers of the non-radiative matching patch array can be arranged.

[0097] Example embodiments have been disclosed herein, and although specific terms are employed, they are used and should be interpreted only in a general illustrative sense and not for limiting purposes. In some instances, it will be apparent to those skilled in the art that, unless otherwise expressly noted, features, characteristics, and / or elements described in conjunction with a particular embodiment may be used alone or in combination with features, characteristics, and / or elements described in conjunction with other embodiments. Therefore, those skilled in the art will appreciate that various changes in form and detail may be made without departing from the scope of the present disclosure as set forth in the appended claims.

Claims

1. An antenna unit, comprising a radiator, It is characterized in that The radiator includes a first radiator and a second radiator, and the first radiator and the second radiator are arranged at intervals along the thickness direction of the antenna unit; the first radiator includes a plurality of uniformly distributed first patch units, and the second radiator includes a plurality of uniformly distributed second patch units; the projection of the first patch unit on the antenna unit plane has an overlapping part with the projection of at least one of the second patch units on the antenna unit plane, wherein the antenna unit plane is a plane perpendicular to the thickness direction of the antenna unit.

2. The antenna unit according to claim 1, It is characterized in that The first radiator is an array composed of M×M first patch units, and the spacing between adjacent first patch units is equal; the second radiator is an array composed of N×N second patch units, and the spacing between adjacent second patch units is equal; wherein M and N are positive integers not less than 2, M=N; the spacing between the first patch units is equal to the spacing between the second patch units.

3. The antenna unit according to claim 2, It is characterized in that The multiple first patch units correspond one-to-one to the multiple second patch units, the size of the first patch unit is consistent with the size of the second patch unit, and the projection of the first patch unit on the antenna unit plane overlaps with the projection of the corresponding second patch unit on the antenna unit plane.

4. The antenna unit according to claim 3, It is characterized in that The second patch unit is a subarray consisting of l×l second sub-patch units, and the polarization direction of the second sub-patch unit is the same as the polarization direction of the first patch unit, where l is an integer.

5. The antenna unit according to claim 1, It is characterized in that The first radiator is an array composed of M×M first patch units, and the spacing between adjacent first patch units is equal; the second radiator is an array composed of N×N second patch units, and the spacing between adjacent second patch units is equal; wherein M and N are positive integers not less than 2, and M≠N.

6. The antenna unit according to claim 5, It is characterized in that The size of the first patch unit is inconsistent with the size of the second patch unit.

7. The antenna unit according to claim 1, It is characterized in that The first patch unit has a uniform and symmetrical shape, and the second patch unit has a uniform and symmetrical shape.

8. The antenna unit according to claim 7, It is characterized in that The shape of the first patch unit is one of a square, a rectangle and a rhombus, and the shape of the second patch unit is one of a square, a rectangle and a rhombus.

9. The antenna unit according to any one of claims 1 to 8, It is characterized in that The antenna unit also includes a non-radiative matching patch array composed of a plurality of non-radiative matching patches, wherein the non-radiative matching patches are arranged along the polarization direction of the first radiator, and the side lengths of the non-radiative matching patches arranged along the same polarization direction are equal; and the projection of the non-radiative matching patch array on the plane of the antenna unit has no overlapping part with the projection of the first radiator on the plane of the antenna unit.

10. The antenna unit according to claim 9, It is characterized in that The non-radiative matching patch array and the first radiator are arranged on the same layer; or The non-radiative matching patch array and the first radiator are arranged on different layers.

11. The antenna unit according to any one of claims 1 to 8, It is characterized in that The antenna unit further includes a reflection surface and a feeder, the reflection surface includes a first metal floor and a second metal floor, the first metal floor is arranged on a side of the feeder close to the radiator, and the second metal floor is arranged on a side of the feeder away from the radiator; The first metal floor is connected to the second metal floor through interconnection vias, and a gap is arranged on the first metal floor.

12. The antenna unit according to claim 11, It is characterized in that The feed line is composed of a strip line loaded with tuning branches, and the feed line corresponds to the gap on the reflection surface.

13. The antenna unit according to claim 12, It is characterized in that The gap includes a first gap and a second gap; the first gap is composed of a first sub-gap and at least one second sub-gap that are connected, and the extension direction of the first sub-gap intersects with the extension direction of the second sub-gap; The second slit is composed of a third sub-slit and at least one fourth sub-slit that are connected, and an extension direction of the third sub-slit intersects with an extension direction of the fourth sub-slit; An extension direction of the first sub-slot intersects with an extension direction of the third sub-slot, and an extension direction of the second sub-slot intersects with an extension direction of the fourth sub-slot; The feed line includes a first feed line corresponding to the first slot and a second feed line corresponding to the second slot; an extension direction of the strip line of the first feed line intersects with an extension direction of the first sub-slot, and a strip line of the second feed line intersects with an extension direction of the third sub-slot; The projection of the first feed line on the antenna unit plane has an overlapping part with the projection of the first sub-slot on the antenna unit plane, and the projection of the second feed line on the antenna unit plane has an overlapping part with the projection of the third sub-slot on the antenna unit plane.

14. An antenna array, It is characterized in that The antenna array is composed of an array of multiple antenna units, and the antenna unit is the antenna unit according to any one of claims 1 to 13.

15. The antenna array according to claim 14, It is characterized in that The center distance between adjacent antenna units is 0.3-1 free space wavelength.

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