Frequency selective surface structure, antenna system and base station

Abstract

The invention provides a frequency selective surface structure, an antenna system and a base station. The frequency selective surface structure comprises a frequency selective surface, a feed network and a phase shifter. The frequency selective surface comprises a metal layer, the phase shifter is electrically connected with the feed network, and the phase shifter and the feed network are integrated on the metal layer of the frequency selective surface. In addition, the frequency selective surface structure can reduce transmission loss under the condition that the phase shifter does not shield antenna beams, the coverage range and the transmission quality of antenna signals can be considered, and the problem that the phase shifter in the multi-band integrated antenna system is difficult to arrange is solved.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a frequency selective surface structure, an antenna system and a base station. Background Art

[0002] Base station antennas are the foundation of current mobile communications and occupy an important position in mobile communications. In order to meet the growing demand for mobile communication speed and bandwidth, it is necessary to design communication systems with higher speed and larger capacity. Base station antenna systems are evolving from the fourth generation of mobile communication technology (4th-generation, 4G) to the fifth generation of mobile communication technology (5th-generation, 5G). A key technology at present is to provide operators with multi-band integrated antenna systems.

[0003] In the existing multi-band integrated antenna system, antennas of multiple frequency bands are stacked, and each layer of antennas is equipped with a corresponding feeding network. Since multiple antennas are stacked on each other in the antenna system, the signals between antennas of different frequency bands interfere with each other, resulting in distortion of the antenna radiation pattern. In order to reduce the mutual influence between antennas of different frequency bands and obtain the required antenna waveform, phase shifters, frequency selective surfaces and other structures are usually set in the multi-band integrated antenna system. By changing the passband, band-stop characteristics and phase modulation of the feeding network, flexible beam scanning is achieved, and the coupling effect between antennas of different frequency bands is reduced, thereby obtaining an ideal antenna waveform. At the same time, it can also increase the coverage of base station antennas and adapt to the installation layout requirements of multiple scenarios.

[0004] However, when the antennas are arranged at a high density, the layout of the phase shifters becomes a major problem. Since the phase shifters need to be connected to the antenna's feed network, when multiple antennas are stacked, some phase shifters also need to be laid out between the stacked antennas along with the antenna's feed network. The phase shifters themselves have a certain size, so they will block the beams of some antennas, affecting the coverage of the antenna signals. The intuitive feeling given to users is that the network speed in some areas is too slow or there is a signal blind spot.

[0005] In order to prevent the phase shifter from blocking the antenna waveform, some operators have improved the layout of the antenna system and phase shifter, and staggered the phase shifter and the affected antenna through partition layout and other methods. Although this method can improve the phenomenon of the phase shifter blocking the antenna waveform to a certain extent, it will cause problems such as increased antenna size and less compact layout, and the transmission line structure between the phase shifter and the radiator of the antenna system will be lengthened, resulting in increased losses due to long-distance transmission.

[0006] Therefore, the phase shifter layout of the multi-band integrated antenna system in the prior art is difficult, and will cause high transmission loss when the phase shifter does not block the antenna beam, and it is impossible to take into account both the coverage range and the transmission quality of the antenna signal. Summary of the invention

[0007] The frequency selective surface structure, antenna system and base station provided in the embodiments of the present application solve the difficulties in the phase shifter layout of the multi-band integrated antenna system in the prior art. When the phase shifter does not block the antenna waveform, it will cause higher transmission loss and cannot take into account the coverage range and transmission quality of the antenna signal.

[0008] The embodiment of the present application provides a frequency selective surface structure, including a frequency selective surface, a feeding network and a phase shifter. The frequency selective surface includes a metal layer, the phase shifter is electrically connected to the feeding network, and the phase shifter and the feeding network are integrated in the metal layer of the frequency selective surface.

[0009] The frequency selective surface structure provided in the embodiment of the present application can be applied to the antenna system, and the phase shifter and the feed network are integrated on the metal layer of the frequency selective surface. The metal layer of the frequency selective surface has spatial filter characteristics. By changing the wave transmission characteristics of the antenna through the design of the metal layer, the requirements of the antenna electromagnetic wave transmission control can be met. The frequency selective surface can be designed to have a completely transparent effect on part of the antenna, that is, a structure that is electromagnetically transparent to part of the antenna. The phase shifter and the feed network are integrated on the metal layer, and the metal layer has a stealth effect on the phase shifter. If a miniaturized phase shifter is used, the phase shifter can be completely hidden on one side of the metal layer, and the metal layer also has the same stealth effect on the transmission line structure in the feed network. The feed network and the phase shifter will not affect the filtering characteristics of the frequency selective surface structure. In this way, the frequency selective surface structure composed of the frequency selective surface, the phase shifter and the feed network can still produce an electromagnetically transparent effect on part of the antenna, so as not to block the beam of the antenna. The other part of the antenna can be set on the other side of the frequency selective surface structure, so that its electromagnetic wave radiates in the direction away from the frequency selective surface structure, and the phase shifter will not block the beam of this part of the antenna. Furthermore, since the phase shifter and the feeding network are integrated together and the structure is compact, the length of the transmission line structure in the feeding network can be shortened, and the transmission loss can be reduced.

[0010] Therefore, the frequency selective surface structure provided in the present application can reduce transmission loss without blocking the antenna beam by the phase shifter, and can take into account both the coverage range and transmission quality of the antenna signal, thus solving the problem of difficult layout of phase shifters in multi-band integrated antenna systems.

[0011] In some embodiments, the metal layer has a metal area, and a hollow area is formed around the metal area; the feeding network and the phase shifter are integrated in the metal area, and the projections of the feeding network and the phase shifter to the metal layer along a first direction are located as a whole in the metal area; wherein the first direction is perpendicular to the plane where the metal layer is located.

[0012] With the above solution, the phase shifter and the feed network are integrated on the metal area and carried by the metal area. The phase shifter and the feed network are not overlapped with the hollow area in the first direction to prevent the phase shifter and the feed network from blocking the antenna beam.

[0013] In some embodiments, the metal layer includes a metal grid, the metal grid constitutes a metal area, and the space enclosed by each grid in the metal grid together constitutes a hollow area. The grid-shaped frequency selective surface has a relatively regular shape and is easy to process, and the grid lines in the metal grid are convenient for wiring.

[0014] In some embodiments, the metal layer includes a metal grid and a plurality of metal patches, and the plurality of metal patches are correspondingly arranged in a plurality of grids of the metal grid. The metal grid and the metal patches constitute a metal area, and the gap between the metal patches and the metal grid constitutes a hollow area. The grid-shaped frequency selective surface has a relatively regular shape and is easy to process, and the grid lines in the metal grid are convenient for wiring, and the feed network and phase shifter can also be arranged on the metal patches.

[0015] In some embodiments, the frequency selective surface includes multiple metal layers stacked and arranged parallel to each other in a first direction, and the feed network and the phase shifter are integrated on at least one metal layer of the multiple metal layers. The first direction is perpendicular to the plane where the metal layers are located.

[0016] In some embodiments, the multiple metal layers include two metal layers, each of the two metal layers includes two surfaces opposite to each other in a first direction, and the feeding network and the phase shifter are integrated on any one or more surfaces of the two metal layers.

[0017] In some embodiments, the feed network includes a plurality of transmission line structures, and: the frequency selective surface structure includes a phase shifter, and the phase shifter is electrically connected to all of the plurality of transmission line structures. Alternatively, the frequency selective surface structure includes a plurality of phase shifters, and each of the plurality of phase shifters is electrically connected to a portion of the plurality of transmission line structures.

[0018] In some embodiments, the phase shifter includes an outer conductor, a fixed medium, a sliding medium and at least one signal line winding. A receiving cavity is formed in the outer conductor, and the fixed medium, the sliding medium and the at least one signal line winding are all received in the receiving cavity. The fixed medium is fixedly connected to the outer conductor, and the sliding medium is located between the fixed medium and the outer conductor, and is slidably connected to the fixed medium; each signal line winding in the at least one signal line winding is wound and fixed to the fixed medium, and each signal line winding is located between the fixed medium and the sliding medium, and the phase shifter is electrically connected to the feed network through each signal line winding. At least a portion of the outer conductor is set as a planar structure, and the phase shifter is fixedly connected to the metal layer through the planar structure.

[0019] With the above solution, the signal line winding is fixed on the fixed medium, and the sliding medium covers the surface of the signal line winding and can slide on the surface of the signal line winding. By changing the position of the sliding medium, the range of each signal line winding covered by the sliding medium can be changed, and the part of the signal line winding not covered by the sliding medium is exposed to the air, so that the electrical length of the signal line winding changes, thereby changing the phase shift amount of the radiator corresponding to each signal line winding.

[0020] In some embodiments, at least one signal line winding is a plurality of signal line windings, and the plurality of signal line windings constitute at least one group of signal line windings, and each group of signal line windings in at least one group of signal line windings includes at least one signal line winding. In each group of signal line windings, at least one signal line winding is one signal line winding or at least two signal line windings, one end of one signal line winding or one end of at least two signal line windings are connected to form an input end of a phase shifter, and the other end of at least one signal line winding constitutes at least one output end of the phase shifter, and each of the at least one output end is electrically connected to a corresponding transmission line structure. A phase shifter can perform phase modulation on multiple radiators.

[0021] In some embodiments, the plurality of transmission line structures include at least one first transmission line structure, each of the at least one first transmission line structure includes an outer conductor and a core, the core is wrapped in a cavity inside the outer conductor, and there is a gap between the core and the outer conductor.

[0022] At least a portion of the outer conductor is arranged as a planar structure, and the first transmission line structure is fixedly connected to the metal layer via the planar structure.

[0023] In the above solution, the medium between the outer conductor and the core is air. The core is suspended in the cavity of the outer conductor as a whole, and the core is surrounded by the air in the cavity. The dielectric constant of air is small, which can reduce the transmission loss of the first transmission line structure.

[0024] In some embodiments, the first transmission line structure further includes a plurality of support members disposed between the outer conductor and the core body, the plurality of support members are disposed at intervals along an extension direction of the core body, and the core body is fixedly connected to the outer conductor through the plurality of support members.

[0025] In some embodiments, the first transmission line structure includes a plurality of cores arranged at intervals, and: the outer conductor has a cavity, and the plurality of cores are located in the cavity. Alternatively, the outer conductor has a plurality of cavities that are interconnected, and the plurality of cavities correspond to the plurality of cores one by one, and each core is located in a corresponding cavity.

[0026] In some embodiments, the plurality of transmission line structures include at least one second transmission line structure, each of the at least one second transmission line structure is configured as a power divider, the power divider includes a conductive shell and a battery cell, the battery cell is wrapped in a cavity inside the conductive shell, and there is a gap between the battery cell and the conductive shell; the battery cell has an input end and a plurality of output ends, and the input end of the battery cell is electrically connected to the phase shifter;

[0027] At least a portion of the conductive housing is configured as a planar structure, and the second transmission line structure is fixedly connected to the metal layer via the planar structure.

[0028] With the above solution, the battery cell is suspended in a conductive shell and surrounded by air to reduce the transmission loss of the power divider.

[0029] In some embodiments, when the phase shifter includes an outer conductor, the outer conductor of the phase shifter is electrically connected to the metal layer. When the feed network includes a plurality of transmission line structures, the plurality of transmission line structures include at least one first transmission line structure, and each of the at least one first transmission line structure includes an outer conductor, the outer conductor of each first transmission line structure is electrically connected to the metal layer. When the feed network includes a plurality of transmission line structures, the plurality of transmission line structures include at least one first transmission line structure, and each of the at least one second transmission line structure includes a conductive shell, the conductive shell of each second transmission line structure is electrically connected to the metal layer.

[0030] The electrical connection mode is any one of the following: coupling connection, direct current connection or segmented direct current connection.

[0031] In some embodiments, the frequency selective surface structure further includes a dielectric layer, the metal layer is mounted on the dielectric layer, and the dielectric layer can be used to support the metal layer.

[0032] An embodiment of the present application also provides an antenna system, including a floor, a plurality of antennas stacked in a first direction, and a plurality of feeding networks for feeding the plurality of antennas, wherein the floor is arranged on one side of the plurality of antennas in the first direction, and the antenna system further includes the frequency selective surface structure provided in any of the above embodiments; the frequency selective surface structure is arranged between adjacent antennas stacked in the plurality of antennas, and the feeding network of the frequency selective surface structure constitutes a feeding network of at least one antenna in the adjacent antennas stacked and away from the floor.

[0033] The antenna system provided by the embodiment of the present application can also reduce transmission loss when the phase shifter does not block the antenna beam, can take into account the coverage and transmission quality of the antenna signal, and also has a small size, low cost and easy assembly. In some embodiments, the multiple antennas include a first antenna and a second antenna stacked in a first direction, the floor is arranged on the side of the second antenna away from the first antenna, and the frequency selective surface structure is arranged between the first antenna and the second antenna.

[0034] The first antenna and the second antenna both include a plurality of radiators distributed in an array. At least part of the feeding network of the frequency selective surface structure constitutes the feeding network of the first antenna and is electrically connected to the plurality of radiators of the first antenna to feed the plurality of radiators of the first antenna.

[0035] In some embodiments, when the frequency selective surface structure includes two metal layers, the feeding network and the phase shifter of the frequency selective surface structure are integrated on a metal layer of the two metal layers that is far away from the second antenna.

[0036] In some embodiments, the plurality of radiators of the first antenna constitute at least one column of radiators, and each column of the at least one column of radiators includes at least two radiators spaced apart along the second direction. When the feeding network of the frequency selective surface structure includes a plurality of transmission line structures, each column of radiators has transmission line structures symmetrically distributed on both sides of the third direction, and each column of radiators has phase shifters symmetrically distributed on both sides of the third direction. The first direction, the second direction, and the third direction are mutually perpendicular in pairs.

[0037] By adopting the above solution, when the first antenna is a dual-polarized antenna, the phase shifter can perform phase modulation on two polarization directions in the first antenna respectively.

[0038] In some embodiments, the plurality of antennas further include a third antenna, which is disposed on a side of the frequency selective surface structure away from the floor. The third antenna includes a plurality of radiators distributed in an array, and the plurality of radiators of the third antenna and the plurality of radiators of the first antenna are alternately arranged in a plane perpendicular to the first direction. At least part of the feeding network of the frequency selective surface structure constitutes the feeding network of the third antenna, and is electrically connected to the plurality of radiators of the third antenna to feed the plurality of radiators of the third antenna.

[0039] In some embodiments, the plurality of radiators of the third antenna constitute at least one column of radiators, and each column of the at least one column of radiators includes at least two radiators spaced apart along the second direction. When the feeding network of the frequency selective surface structure includes a plurality of transmission line structures, each column of radiators has transmission line structures symmetrically distributed on both sides of the third direction, and each column of radiators has phase shifters symmetrically distributed on both sides of the third direction; wherein the first direction, the second direction, and the third direction are mutually perpendicular in pairs. When the third antenna is a dual-polarized antenna, the phase shifter can adjust the two polarization directions in the third antenna respectively.

[0040] In some embodiments, when the frequency selective surface structure includes two metal layers, phase shifters and feeding networks are integrated on both metal layers. The portion of the feeding network of the frequency selective surface that constitutes the first antenna is integrated on any one of the two metal layers, and the portion of the feeding network of the frequency selective surface that constitutes the third antenna is integrated on the other of the two metal layers. The first feeding network and the third feeding network are arranged in layers, which facilitates wiring on different metal layers and makes rational use of space.

[0041] In some embodiments, the antenna system is formed on a printed circuit board. The printed circuit board includes a metal structure and a dielectric structure, at least part of the metal structure constitutes a floor, a plurality of radiators of each of the plurality of antennas, and a metal layer of a frequency selective surface structure; when the frequency selective surface structure further includes a dielectric layer, at least part of the dielectric structure of the printed circuit board constitutes the dielectric layer of the frequency selective surface structure.

[0042] The embodiment of the present application also provides a base station, which includes the antenna system provided by any of the above embodiments and a radio frequency module connected to the antenna system. The base station has high overall integration, wide signal coverage, and fewer signal blind spots. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1a-1b Schematic diagram of the structure of antenna system in some schemes;

[0044] Figure 2a-2b Schematic diagram of the structure of the antenna system in some other schemes;

[0045] Figure 3 This is a schematic diagram of the working principle of the first implementation mode of the antenna system of the embodiment of the present application;

[0046] Figure 4a-Figure 4b-2 This is a structural schematic diagram of a first implementation mode of the antenna system according to an embodiment of the present application from one angle;

[0047] Figure 5a-5c This is a structural schematic diagram of another angle of the first implementation mode of the antenna system of the embodiment of the present application;

[0048] Figure 6 This is a schematic diagram of the working principle of the second implementation mode of the antenna system of the embodiment of the present application;

[0049] Figure 7 This is a schematic structural diagram of a second implementation of the antenna system of an embodiment of the present application;

[0050] Figure 8 This is a structural schematic diagram of another angle of the second implementation mode of the antenna system of the embodiment of the present application;

[0051] Fig. 9 A schematic diagram of the structure of a frequency selective surface according to an embodiment of the present application;

[0052] Fig.10a This is a structural schematic diagram of another implementation of the frequency selective surface structure of the embodiment of the present application;

[0053] Fig.10b for Fig.10a Schematic diagram of the local connection structure of part A;

[0054] Fig.11a This is a schematic structural diagram of a phase shifter in a frequency selective surface structure according to an embodiment of the present application;

[0055] Fig.11b A schematic structural diagram of another implementation of a phase shifter in a frequency selective surface structure according to an embodiment of the present application;

[0056] Figure 12a-12c A schematic diagram of the connection between the phase shifter and the metal layer in the frequency selective surface structure of an embodiment of the present application;

[0057] Figure 13a-Figure 13b-2 This is a structural schematic diagram of a first implementation mode of a first transmission line structure in a frequency selective surface structure of an embodiment of the present application, wherein: Figure 13b-1 for Fig.13a Cross-sectional view along the BB direction, Figure 13b-2 for Fig.13a Cross-section view in the CC direction;

[0058] Fig.14a This is a structural schematic diagram of a second implementation mode of the first transmission line structure in the frequency selective surface structure of an embodiment of the present application;

[0059] Fig.14b It is a structural schematic diagram of a third implementation mode of the first transmission line structure in the frequency selective surface structure of an embodiment of the present application;

[0060] Figure 15a-Figure 15b-2 This is a structural schematic diagram of a fourth implementation mode of the first transmission line structure in the frequency selective surface structure of an embodiment of the present application, wherein: Figure 15b-1 for Fig.15aCross-section along the mid-DD direction; Figure 15b-2 for Fig.15a Cross-section along the EE direction;

[0061] Figure 16a-16b This is a structural schematic diagram of the fifth implementation mode of the first transmission line structure in the frequency selective surface structure of the embodiment of the present application, wherein: Fig.16b for Fig.16a Cross-sectional view in the FF direction;

[0062] Fig.17 It is a structural schematic diagram of a sixth implementation mode of the first transmission line structure in the frequency selective surface structure of an embodiment of the present application;

[0063] Fig.18 This is a structural schematic diagram of a seventh implementation mode of the first transmission line structure in the frequency selective surface structure of an embodiment of the present application;

[0064] Fig.19 This is a schematic diagram of the structure of a power divider in a frequency selective surface structure according to an embodiment of the present application;

[0065] Figure 20a-Figure 20c A schematic diagram of the connection between the transmission line structure and the metal layer in the frequency selective surface structure of an embodiment of the present application;

[0066] Fig.21 This is a schematic diagram of the structure of a base station according to an embodiment of the present application.

[0067] Description of reference numerals:

[0068] Some solutions:

[0069] 100': Antenna system;

[0070] 1': first antenna; 10': radiator;

[0071] 2': second antenna; 20': radiator;

[0072] 3': floor; 4': phase shifter; 5': feed network; 6': frequency selective surface;

[0073] z': first direction; y': second direction; x': third direction.

[0074] Other options:

[0075] 100”: Antenna system;

[0076] 1”: first antenna; 10”: radiator;

[0077] 2”: second antenna; 20”: radiator;

[0078] 3”: floor; 4”: phase shifter;

[0079] 5”: Feed network; 51”: Transmission line structure;

[0080] 6”: frequency selective surface;

[0081] z”: first direction; y”: second direction; x”: third direction.

[0082] Embodiments of the present application:

[0083] 100: antenna system;

[0084] 1: first antenna; 10: radiator; 11: first feeding network;

[0085] 2: second antenna; 20: radiator; 21: second feeding network;

[0086] 3: third antenna; 30: radiator; 31: third feeding network;

[0087] 4: Floor;

[0088] 200: Frequency selective surface structure;

[0089] 5: Frequency selective surface;

[0090] 51: metal layer; 511: first metal layer; 512: second metal layer;

[0091] 513: Metal area; 5131: Metal grille; 5132: Metal patch;

[0092] 514: hollow area;

[0093] 6: phase shifter; 61: input end; 62: output end;

[0094] 63: outer conductor; 63a: bottom;

[0095] 64: fixed medium; 65: sliding medium; 66: signal line winding;

[0096] 7: Feed network; 71: Transmission line structure;

[0097] 711: first transmission line structure; 7110: cavity;

[0098] 7111: outer conductor; 7111a: bottom; 7112: core;

[0099] 7113: gap; 7114: support member;

[0100] 712: power divider; 7121: conductive housing;

[0101] 7122: battery cell; 7122a: input terminal; 7122b: output terminal; 7123: gap;

[0102] 72: Feeder;

[0103] 300: base station; 8: radio frequency module;

[0104] z: first direction; y: second direction; x: third direction. DETAILED DESCRIPTION

[0105] The following specific embodiments illustrate the implementation of the present application, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Although the description of the present application will be introduced in conjunction with some embodiments, this does not mean that the features of this application are limited to the implementation. On the contrary, the purpose of introducing the application in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present application. In order to provide a deep understanding of the present application, the following description will include many specific details. The present application can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present application, some specific details will be omitted in the description. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0106] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0107] The following explains the terms that may appear in the embodiments of the present application.

[0108] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0109] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0110] Coupling: can be understood as direct coupling and / or indirect coupling, and "coupled connection" can be understood as direct coupling connection and / or indirect coupling connection. Direct coupling can also be called "electrical connection", which is understood as the physical contact and electrical conduction between components; it can also be understood as the connection between different components in the circuit structure through physical lines such as printed circuit board (PCB) copper foil or wires that can transmit electrical signals; "indirect coupling" can be understood as two conductors being electrically conductive in an airless / non-contact manner. In one embodiment, indirect coupling can also be called capacitive coupling, for example, signal transmission is achieved by coupling between the gaps between two conductive parts to form an equivalent capacitor.

[0111] Ground / floor: can refer to at least a part of any grounding layer, grounding plate, or grounding metal layer, etc. in a communication device (such as a base station), or at least a part of any combination of any of the above grounding layers, grounding plates, or grounding components, etc., and "ground / floor" can be used for grounding components in a communication device. In one embodiment, the "ground / floor" may include any one or more of the following: a grounding layer of a circuit board of a communication device, a grounding plate formed by a middle frame of the communication device, a grounding metal layer formed by a metal film under the screen, a conductive grounding layer of a battery, and a conductive part or metal part electrically connected to the above grounding layer / grounding plate / metal layer. In one embodiment, the circuit board may be a printed circuit board (PCB), such as an 8-layer, 10-layer, or 12-14-layer board having 8, 10, 12, 13, or 14 layers of conductive material, or an element separated and electrically insulated by a dielectric layer or insulating layer such as glass fiber, polymer, etc. In one embodiment, the circuit board includes a dielectric substrate, a grounding layer, and a routing layer, and the routing layer and the grounding layer are electrically connected through vias. In one embodiment, components such as a display, a touch screen, input buttons, a transmitter, a processor, a memory, a battery, a charging circuit, a system on chip (SoC) structure, etc. can be mounted on or connected to a circuit board; or electrically connected to a wiring layer and / or a ground layer in the circuit board. For example, a radio frequency source is disposed on the wiring layer.

[0112] Any of the above-mentioned grounding layers, grounding plates, or grounding metal layers are made of conductive materials. In one embodiment, the conductive material can be any of the following materials: copper, aluminum, stainless steel, brass and their alloys, copper foil on an insulating substrate, aluminum foil on an insulating substrate, gold foil on an insulating substrate, silver-plated copper, silver-plated copper foil on an insulating substrate, silver foil and tin-plated copper on an insulating substrate, cloth impregnated with graphite powder, graphite-coated substrates, copper-plated substrates, brass-plated substrates, and aluminum-plated substrates. It will be appreciated by those skilled in the art that the grounding layer / grounding plate / grounding metal layer can also be made of other conductive materials.

[0113] Electrical length: Electrical length can be expressed as the ratio of the physical length (i.e. mechanical length or geometric length) multiplied by the transmission time of an electrical or electromagnetic signal in a medium to the time required for the signal to pass the same distance as the physical length of the medium in free space. The electrical length can satisfy the following formula:

[0114]

[0115] Where L is the physical length, a is the transmission time of the electrical or electromagnetic signal in the medium, and b is the transmission time in free space.

[0116] Alternatively, electrical length can also refer to the ratio of physical length (i.e. mechanical length or geometric length) to the wavelength of the transmitted electromagnetic wave. The electrical length can satisfy the following formula:

[0117]

[0118] Where L is the physical length and λ is the wavelength of the electromagnetic wave.

[0119] Dielectric constant: the main parameter reflecting the dielectric properties or polarization properties of a dielectric under the action of an electrostatic field.

[0120] Transmittance: The ratio of the electromagnetic wave to the medium before and after it penetrates glass. The higher the transmittance, the more electromagnetic waves pass through the medium, and the lower the transmittance, the fewer electromagnetic waves pass through the medium.

[0121] Reflectivity: The ratio of the signal received by the antenna in the reverse direction to the forward signal, which is the ratio of the reflected wave to the incident wave.

[0122] Antenna pattern: also called radiation pattern. It refers to the graph of the relative field strength (normalized modulus) of the antenna radiation field changing with direction at a certain distance from the antenna.

[0123] The limitations such as colinearity, coaxiality, coplanarity, symmetry (e.g., axisymmetry, or center symmetry, etc.), parallelism, perpendicularity, sameness (e.g., same length, same width, etc.) mentioned in the embodiments of the present application are all for the current technological level, rather than an absolutely strict definition in a mathematical sense. There may be a deviation of a predetermined angle (e.g., ±5°, ±10°) between two structures that are parallel or perpendicular to each other.

[0124] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0125] Base station antennas are the foundation of current mobile communications and occupy an important position in mobile communications. In order to meet the growing demand for mobile communication speed and bandwidth, it is necessary to design communication systems with higher speed and larger capacity. Base station antenna systems are evolving from the fourth generation of mobile communication technology (4th-generation, 4G) to the fifth generation of mobile communication technology (5th-generation, 5G). A key technology at present is to provide operators with multi-band integrated antenna systems.

[0126] In the existing multi-band integrated antenna system, antennas of multiple frequency bands are stacked, and each layer of antennas is provided with a corresponding feeding network. Since multiple antennas are stacked on each other in the antenna system, the signals between antennas of different frequency bands interfere with each other, resulting in distortion of the antenna radiation pattern. In order to reduce the mutual influence between antennas of different frequency bands and obtain the required antenna waveform, phase shifters, frequency selective surfaces and other structures are usually set in the multi-band integrated antenna system. By changing the passband, band-stop characteristics and phase modulation of the feeding network, flexible beam scanning is achieved, and the coupling effect between antennas of different frequency bands is reduced, thereby obtaining an ideal antenna waveform. At the same time, it can also increase the coverage of base station antennas and adapt to the installation layout requirements of multiple scenarios.

[0127] However, when the multi-band antenna array is arranged at a high density, the layout of the phase shifter becomes a major problem. Since the phase shifter needs to be connected to the antenna's feed network, when multiple antennas are stacked, some phase shifters also need to be laid out between the stacked antennas along with the antenna's feed network. The phase shifter itself has a certain size, so it will block the beam of some antennas, affecting the coverage of the antenna signal. The intuitive feeling brought to users is that the network speed in some areas is too slow or there is a signal blind spot.

[0128] In order to prevent the phase shifter from blocking the antenna waveform, some operators have improved the layout of the antenna system and phase shifter, and staggered the phase shifter and the affected antenna through partition layout and other methods. Although this method can improve the phenomenon of the phase shifter blocking the antenna beam to a certain extent, it will cause problems such as increased antenna size and less compact layout, making the transmission line structure between the phase shifter and the feed network longer, and increasing the loss due to long-distance transmission. Therefore, the phase shifter layout of the multi-band integrated antenna system in the prior art is difficult, and it will bring higher transmission loss when the phase shifter does not block the antenna beam, and it is impossible to take into account the coverage range and transmission quality of the antenna signal.

[0129] The following takes two antenna systems as examples to specifically explain the layout of phase shifters in antenna systems.

[0130] See also Figure 1a-1b , Figure 1a-1b Schematic diagram of the structure of the antenna system in some schemes.

[0131] like Figure 1a-1b As shown, the antenna system 100' includes a first antenna 1' and a second antenna 2' stacked in a first direction z', a floor 3' is placed under the second antenna 2', the first antenna 1' is located above the second antenna 2', and a frequency selective surface 6' integrating a feeding network 5' of the first antenna 1' is provided between the first antenna 1' and the second antenna 2', and a phase shifter 4' connected to the feeding network 5'. The first antenna 1' and the second antenna 2' both include a plurality of radiators, and the plurality of radiators of each antenna constitute a plurality of columns of radiators, each column of radiators includes at least two radiators arranged at intervals along the second direction y', and the plurality of columns of radiators are arranged along the third direction x'. The electromagnetic wave of the second antenna 2' is radiated toward the side where the first antenna 1' is located as a whole in the first direction z'. In order to reduce the shielding of the second antenna 2' beam by the phase shifter 4', in the third direction x', the phase shifter 4' is arranged on both sides of all radiators 10' of the first antenna 1', and the phase shifter 4' is located outside the two sides of the frequency selective surface 6'. With this structure, when the electromagnetic waves of each radiator 20' in the second antenna 2' radiate vertically (radiate along the first direction z' to the side where the first antenna 1' is located), the phase shifter 4' will not block the beam of the second antenna 2'. However, when the radiator 20' of the second antenna 2' radiates in a direction that is at a certain angle to the first direction z', the phase shifter 4' will still block the beam of the second antenna 2', increasing the wave transmission loss of the second antenna 2', affecting the coverage of the antenna signal, causing slow network speeds in some areas, signal blind spots, and other problems. In addition, this layout method increases the size of the antenna system in the third direction, affecting the competitiveness of base station antenna products.

[0132] See also Figure 2a-2b , Figure 2a-2bSchematic diagram of the structure of the antenna system in other schemes.

[0133] like Figure 2a-2b As shown, the antenna system 100" includes a first antenna 1" and a second antenna 2" stacked in a first direction z", with the second antenna 2" connected to a floor 3" below. The first antenna 1" is located above the second antenna 2", and a feeding network 5" of the first antenna 1" is arranged between the first antenna 1" and the second antenna 2". The first antenna 1" and the second antenna 2" both include a plurality of radiators, and the plurality of radiators of each antenna constitute a plurality of columns of radiators, each column of radiators includes at least two radiators spaced apart along the second direction y", and the plurality of columns of radiators are arranged along a third direction x". The plurality of radiators 20" of the second antenna 2" are concentrated in one area, and only a portion of the first antenna 1" and the second antenna 2" are stacked. In order to reduce the obstruction of the second antenna beam by the phase shifter 4", the phase shifter 4" is arranged at a position where the second antenna 2" is not set, so that the phase shifter 4" and the second antenna 2" are offset in the second direction y", and the two are not overlapped in the first direction z". At the same time, a frequency selective surface 6" is set directly above the second antenna 2", and the frequency selective surface 6" is an electromagnetically transparent structure to the second antenna 2", and the electromagnetic waves radiated by the second antenna 2" can pass through the frequency selective surface 6". With this structure, the beam of the second antenna 6" will not be obstructed by the phase shifter 4". However, since the phase of each radiator 10" in the first antenna 1" needs to be adjusted by the phase shifter 4", the phase shifter 4" is electrically connected to each radiator 10" of the first antenna 10" through a transmission line structure 51" (such as a cable, a microstrip line, etc.). The phase shifter 4" is arranged on the side of the frequency selective surface 6" away from the radiator 10" of the first antenna 1", which will cause the length of the transmission line structure 51" between the phase shifter 4" and each radiator 10" in the first antenna 1" to be longer and the transmission loss to be larger, especially for the radiator 10" located directly above the second antenna 2", which is farther away from the phase shifter 4" in the second direction y", resulting in an increase in the length of the transmission line structure 51" between the phase shifter 4" and this part of the radiator 10", and an increase in the transmission loss. In addition, the transmission line structure 51" is fixed on the frequency selective surface 6", and its longer length also increases the number of manual solder joints, making the assembly complicated. When the transmission line structure 51" uses a microstrip line with lower loss, more RF plates are required, which increases the cost.

[0134] To solve the above problems, the present application provides an antenna system, which achieves the effect of invisible phase shifter by integrating both the phase shifter and the feeding network on the frequency selective surface. It can realize that the phase shifter does not block the antenna beam, and at the same time, it can shorten the length of the transmission line structure in the feeding network and reduce transmission loss.

[0135] The technical solutions of the embodiments of the present application can be applied to various communication systems, for example: multi-band integrated antenna system, long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD), universal mobile telecommunication system (UMTS), worldwide interoperability for microwave access (WiMAX) communication system, fifth generation (5G) system or new radio (NR), device to device (D2D) system, vehicle to everything (V2X) system, etc.

[0136] The following is a combination of the structures of several multi-band antenna systems to exemplify the technical solutions adopted by the antenna system of the present application and the beneficial effects produced.

[0137] See also Figure 3-5c , Figure 3 This is a schematic diagram of the working principle of the first implementation mode of the antenna system of the embodiment of the present application; Figure 4a-Figure 4b-2 This is a structural schematic diagram of a first implementation mode of the antenna system according to an embodiment of the present application from one angle; Figure 5a-5c This is a schematic structural diagram from another angle of the first implementation of the antenna system of an embodiment of the present application.

[0138] like Figure 3-5cAs shown, the antenna system 100 includes a floor 4, a plurality of antennas stacked in a first direction z, and a plurality of feeding networks 7 for feeding the plurality of antennas, wherein the floor 4 is arranged on one side of the plurality of antennas in the first direction z. The antenna is used to receive or send signals. It can be understood by those skilled in the art that the types of antennas are not limited, and they can be active antennas, passive antennas, single-polarization antennas, dual-polarization antennas, directional antennas, omnidirectional antennas, and the like. The active antenna is an antenna that integrates a receiving antenna module, a low-noise amplifier module, a power supply module, and the like, requires an additional power supply, may have multiple input and output ports, and has a relatively complex circuit, while the passive antenna is an antenna without any active device, generally has only a single output port, has a simple structure, is low in cost, and is easy to install. A dual-polarized antenna is an antenna that combines two mutually orthogonal polarization directions of +45° and -45°. It can work in the transmit and receive duplex mode at the same time, which can save the number of antennas of a single directional base station. The use of dual-polarized antennas in mobile communication networks can reduce interference and improve the service quality of the entire network. Therefore, dual-polarized antennas are generally used in mobile communications. Single polarization has only one polarization direction, horizontal or vertical, and its coverage effect is better than that of dual-polarized antennas in open plains or mountainous areas. The antenna system 100 can include multiple types of antennas such as active antennas, passive antennas, single-polarized antennas, dual-polarized antennas, etc., and can be designed according to the actual applicable scenario.

[0139] Each antenna includes a plurality of radiators (also called radiating units) to radiate electromagnetic waves or receive electromagnetic waves. The specific form of the radiator is not limited, for example, it can be a radiator composed of an antenna vibrator. The antenna vibrator can be referred to as a vibrator, which has the function of guiding and amplifying electromagnetic waves.

[0140] The floor 4 is also called a reflector, a bottom plate, or an antenna panel, and is used to reflect electromagnetic waves so that the electromagnetic waves of each antenna are concentrated and radiated in one direction. It can also be used to ground each antenna. The feeding network is also called a power distribution network, and is used to feed power to the antenna. The feeding can be to supply power or energy to the antenna. The function of the feeding network is to feed the signal to each radiator of the antenna according to a certain amplitude and phase, or to feed the signal received from each radiator to the signal processing unit of the base station according to a certain amplitude and phase. Each of the multiple antennas is provided with a corresponding feeding network. The feeding networks between different antennas can be independent or shared. For example, two antennas share one feeding network, etc. This application does not limit this.

[0141] Those skilled in the art will appreciate that the specific number of antennas in the antenna system 100 is not limited, and may be, for example, 2, 3, 4 or more antennas. In one embodiment, the plurality of antennas include a first antenna 1 and a second antenna 2 that are stacked, the first antenna 1 includes a plurality of radiators 10 distributed in an array, the second antenna 2 includes a plurality of radiators 20 distributed in an array, and the floor 4 is disposed on a side of the second antenna 2 that is away from the first antenna 1.

[0142] Among them, the specific number and arrangement of the radiators 10 of the first antenna 1 are not limited and can be designed according to the actual application scenario. In one embodiment, the multiple radiators 10 of the first antenna 1 constitute at least one column of radiators 10, and each column of radiators 10 includes at least two radiators 10 arranged at intervals along the second direction y, wherein the first direction z, the second direction y, and the third direction x are mutually perpendicular. Or it can be understood that the multiple radiators 10 of the first antenna 1 are distributed in a rectangular array, the second direction y can be the length direction of the rectangular array, the third direction x can be the width direction of the rectangular array, and the multiple radiators 10 arranged along the length direction of the rectangular array constitute a column of radiators 10, and at least one column of radiators 10 is arranged along the width direction of the rectangular array (for example, it can be 1 column, 2 columns, 3 columns, etc., which is not specifically limited, and only one column is drawn in the figure as a schematic), and the number of radiators 10 in a column of radiators 10 is at least 2 (such as 2, 3, 4, etc., which is not specifically limited, and only a few are drawn in the figure as a schematic). Likewise, the specific number and arrangement of the radiators 20 of the second antenna 2 are not limited, and may be arranged in a rectangular array or an array of other shapes, which will not be described in detail herein.

[0143] Furthermore, the antenna system 100 also includes a first feeding network 11 for feeding the first antenna 1, and a second feeding network 21 for feeding the second antenna 2. The first feeding network 11 is located between the first antenna 1 and the second antenna 2 in the first direction z, and is electrically connected to each radiator 10 of the first antenna 1. The second feeding network 21 is electrically connected to each radiator 20 of the second antenna 2, and can be located at any position on the side of the first feeding network 11 away from the first antenna 1, for example, it can be integrated on the floor 4, etc., and the present application does not limit this. In one embodiment, the second feeding network 21 is also electrically connected to the floor 4 to achieve grounding.

[0144] It should be noted that in Figure 4a-Figure 5cIn the perspective of the antenna system 100, the antenna system 100 is placed horizontally, and the first antenna 1 and the second antenna 2 are both located above the floor 4. However, in actual application scenarios, the placement of the antenna system 100 is not limited, and it can be placed horizontally (the floor 4 is parallel to the horizontal ground) or vertically (the floor 4 is perpendicular to the horizontal ground). In an example scenario, the antenna system 100 is placed vertically, and the floor 4 is perpendicular to the horizontal ground, so that the number of radiators of the first antenna 1 and the second antenna 2 arranged in the vertical direction (i.e., the second direction y) is greater, and the signal of the antenna system 100 has a wider coverage in the vertical direction, for example, it can cover all floors of a high-rise building.

[0145] Furthermore, the antenna system 100 also includes a frequency selective surface 5 (FSS) disposed between the stacked antennas. The frequency selective surface 5 is a two-dimensional periodic array structure that can effectively control the transmission and reflection of electromagnetic waves and has a specific frequency selection effect. The frequency selective surface 5 can be a spatial filter that exhibits obvious bandpass or bandstop filtering characteristics when interacting with electromagnetic waves. It can be understood by those skilled in the art that the specific form of the frequency selective surface 5 is not limited. For example, it can be transmissive, reflective, or both transmissive and reflective to the incident electromagnetic waves. Please refer to Figure 4b-1 , Figure 4b-2 , Figure 5b-Figure 5c In the direction of the arrow in, in one embodiment, the frequency selective surface 5 is transmissive to the electromagnetic waves of the second antenna 2 and reflective to the electromagnetic waves of the first antenna 1. The electromagnetic waves radiated by the second antenna 2 are reflected on the floor 4 and can be radiated upward through the frequency selective surface 5, that is, the frequency selective surface 5 is an electromagnetically transparent structure to the second antenna 2. The electromagnetic waves of the second antenna 2 are all radiated in the direction away from the floor 4 in the second direction y. The electromagnetic waves of the first antenna 1 are reflected on the frequency selective surface 5 (or it can be understood that the frequency selective surface 5 acts as the floor of the first antenna 1), so that the electromagnetic waves of the first antenna 1 can only radiate in the direction away from the floor 4 in the first direction z, and the radiation directions of the first antenna 1 and the second antenna 2 are consistent.

[0146] The frequency selective surface 5 includes a metal layer 51. The metal layer 51 is a structure that actually produces a spatial filtering effect in the frequency selective surface 5. The metal layer 51 may include a metal region 513 formed of metals of various shapes (see Figure 9-10b ), through the design of the metal area 513, the frequency selective surface 5 can present a bandpass or bandstop characteristic, which will be described in detail later.

[0147] Furthermore, the metal layer 51 of the frequency selective surface 5 is integrated with a phase shifter 6 and a feeding network 7, so that the frequency selective surface 5, the phase shifter 6 and the feeding network 7 constitute a frequency selective surface structure 200. Among them, the phase shifter 6 is a device that can modulate the phase of the antenna output signal. In one embodiment, the phase shifter 6 is electrically connected to each radiator 10 of the first antenna 1 through the feeding network 7 in the frequency selective surface structure 200, so as to control the radiation direction of each radiator 10 and obtain the required antenna waveform. The feeding network 7 of the frequency selective surface structure 200 may include a transmission line structure 71 for signal transmission such as a coaxial cable and a microstrip line, and the feeding network 7 constitutes the feeding network 7 of at least one antenna far away from the floor 4 among the stacked adjacent antennas. In one embodiment, the feeding network 7 constitutes a first feeding network 11, that is, the first feeding network 11 is integrated on the metal layer 51 of the frequency selective surface 5.

[0148] The phase shifter 6 and the first feeding network 11 are integrated on the metal layer 51 of the frequency selective surface 5. A miniaturized phase shifter 6 can be used, and the phase shifter 6 and the transmission line structure 71 in the feeding network 7 are hidden in the metal area 513 of the metal layer 51. The metal layer 51 has a stealth effect on the phase shifter 6 and the feeding network 7. Here, "stealth" can be understood as: the projection of the phase shifter 6 and the feeding network 7 to the metal layer 51 along the first direction z is completely located in the metal area 513. In this form, the phase shifter 6 and the feeding network 7 will not affect the spatial filtering characteristics of the frequency selective surface 5, so that it still exhibits the reflectivity of the first antenna 1 and the transmittance to the second antenna 2. At the same time, the phase shifter 6 and the feeding network 7 will not block the electromagnetic waves of the second antenna 2. In addition, compared to Figure 1a-1b Compared with the antenna system in the present application, the phase shifter 6 in the antenna system 100 does not need to be arranged on both sides of each radiator of the first antenna 1, and thus has a smaller size. Figure 2a and Figure 2b In the antenna system of the present application, the phase shifter 6 and the feed network 7 of the antenna system 100 are integrated together, and the structure is compact, which can shorten the length of the transmission line structure 71 in the feed network 7 and reduce the transmission loss. The shortened length of the transmission line structure 71 also avoids excessive manual solder joints and RF plates, and the cost is lower and the assembly is simpler.

[0149] Therefore, the antenna system 100 provided in the embodiment of the present application can reduce transmission loss when the phase shifter 6 does not block the antenna beam, and can take into account both the coverage range and transmission quality of the antenna signal. At the same time, it has a small size, low cost and is easy to assemble.

[0150] Those skilled in the art will appreciate that the number of metal layers 51 in the frequency selective surface 5 is not limited, and there may be 1, 2, 3 or more metal layers 51. When there are multiple metal layers 51 in the frequency selective surface 5, the phase shifter 6 and the feed network 7 may be integrated on at least one of the metal layers 51. Figure 4b-1 As shown, in one embodiment, the frequency selective surface 5 includes a metal layer 51. Figure 4b-2 , Figure 5b-Figure 5c As shown, in another embodiment, the frequency selective surface 5 includes two metal layers 51 stacked in the first direction z, namely a first metal layer 511 and a second metal layer 512, wherein the second metal layer 512 is located between the first metal layer 511 and the second antenna 2 in the first direction z. Further, the first metal layer 511 and the second metal layer 512 each include two surfaces facing each other in the first direction z, and the feeding network 7 and the phase shifter 6 can be integrated on any one or more surfaces of the two metal layers. Figure 4b-2 , Figure 5b As shown, in one embodiment, the phase shifter 6 and the feeding network 7 are both integrated on the first metal layer 511 and are located on the surface of the first metal layer 511 facing away from the second metal layer 512. Figure 5c As shown, in one embodiment, the phase shifter 6 and the feeding network 7 may also be integrated on the surface of the first metal layer 511 on the side close to the second metal layer 512. In other alternative embodiments, the phase shifter 6 and the feeding network 7 may also be integrated on both the first metal layer 511 and the second metal layer 512, which are not listed here one by one.

[0151] Those skilled in the art can understand that the specific number and layout of the phase shifters 6 are not limited, and the specific number and layout of the transmission line structures 71 in the feeding network 7 are not limited. In one embodiment, the first antenna 1 is a dual-polarized antenna, the frequency selective surface structure 200 includes a plurality of phase shifters 6, the feeding network 7 includes a plurality of transmission line structures 71, and each column of radiators 10 of the first antenna 1 has transmission line structures 71 symmetrically distributed on both sides in the third direction x, and each column of radiators 10 has phase shifters 6 symmetrically distributed on both sides in the third direction x. In this form, the phase shifter 6 can phase modulate the two polarization directions in the first antenna 1 respectively. In other alternative embodiments, if the first antenna 1 is a single-polarized antenna, the phase shifter 6 and the transmission line structure 71 in the feeding network 7 can also be distributed only on one side of the first antenna 1.

[0152] See also Figure 6-Figure 8 , Figure 6 This is a schematic diagram of the working principle of the second implementation mode of the antenna system of the embodiment of the present application; Figure 7 This is a schematic structural diagram of a second implementation of the antenna system of an embodiment of the present application; Figure 8 This is a structural schematic diagram from another angle of the second implementation of the antenna system of an embodiment of the present application.

[0153] like Figure 6-Figure 8 As shown, in one embodiment, the antenna system 100 is further provided with a third antenna 3, and the third antenna 3 is provided on a side of the frequency selective surface structure 200 away from the floor 4. Similarly, the type of the third antenna 3 is not limited. In one embodiment, the third antenna 3 is a dual-polarized antenna.

[0154] Further, the third antenna 3 includes a plurality of radiators 30 distributed in an array, and the plurality of radiators 30 of the third antenna 3 and the plurality of radiators 10 of the first antenna 1 are alternately arranged in a plane perpendicular to the first direction z. The third antenna 3 is correspondingly provided with a third feeding network 31, and at least part of the feeding network 7 of the frequency selective surface structure 200 constitutes the third feeding network 31, and is electrically connected to the plurality of radiators 30 of the third antenna 3 to feed the plurality of radiators 30 of the third antenna 3. Or it can be understood that the first antenna 1 and the third antenna 3 are located in the same layer structure in the first direction z, the radiator 10 of the first antenna 1 and the radiator 30 of the third antenna 3 are cross-distributed in the layer structure, and the third feeding network 31 of the third antenna 3 is also integrated on the metal layer 51 of the frequency selective surface 5, and the feeding network 7 of the frequency selective surface structure 200 simultaneously constitutes the first feeding network 11 and the third feeding network 31. Among them, the first antenna 1 and the third antenna 3 can work in different frequency bands respectively. For example, the first antenna 1 can be a 4G antenna, the third antenna 3 can be a 3G antenna, etc., and this application does not impose any restrictions on this.

[0155] Among them, the specific number and arrangement of the radiators 30 of the third antenna 3 are not limited and can be designed according to the actual application scenario. In one embodiment, the multiple radiators 30 of the third antenna 3 constitute at least one column of radiators, and each column of radiators includes at least two radiators 30 arranged at intervals along the second direction y. Or it can be understood that the multiple radiators 30 of the third antenna 3 are distributed in a rectangular array, the second direction y can be the length direction of the rectangular array, the third direction x can be the width direction of the rectangular array, the radiators 30 arranged along the length direction of the rectangular array constitute a column of radiators, and at least one column of radiators is arranged along the width direction of the rectangular array (for example, it can be 1 column, 2 columns, 3 columns, etc., which are not specifically limited), and the number of radiators 30 in a column of radiators is at least 2 (such as 2, 3, 4, etc., which are not specifically limited, and only a few are drawn in the figure as a schematic).

[0156] like Figure 8As shown, in one embodiment, the first antenna 1 has a column of radiators 10 , the third antenna 3 has two columns of radiators 30 , and the two columns of radiators 30 of the third antenna 3 are distributed on both sides of the column of radiators 10 of the first antenna 1 along the second direction y.

[0157] In one embodiment, each column of radiators of the third antenna 3 is symmetrically provided with transmission line structures 71 on both sides in the third direction x, and each column of radiators is symmetrically provided with phase shifters 6 on both sides in the third direction x. In this form, the phase shifters 6 and the feeding network 7 can respectively adjust the two polarization directions in the third antenna 3. In other alternative embodiments, if the third antenna 3 is a single-polarization antenna, the phase shifters 6 and the transmission line structures 71 in the feeding network 7 can also be distributed only on one side of the third antenna 3.

[0158] like Figure 8 As shown, in one embodiment, the first metal layer 511 and the second metal layer 51 are both integrated with a phase shifter 6 and a feed network 7, and the first feed network 11 is integrated on the second metal layer 512, and the third feed network 31 is integrated on the first metal layer 511, the phase shifter 6 on the first metal layer 511 is electrically connected to the transmission line structure 71 in the third feed network 31, and the phase shifter 6 on the second metal layer 512 is electrically connected to the transmission line structure 71 in the first feed network 11. The first feed network 11 and the third feed network 31 are arranged in layers to facilitate wiring on different metal layers 51 and to make rational use of space. In other alternative embodiments, the first feed network 11 may also be integrated on the first metal layer 511, and the second feed network 21 may also be integrated on the second metal layer 512, and the present application does not limit this.

[0159] The above systematically explains the structure of the antenna system 100 provided in the embodiment of the present application, the functions of each component, and the basic principle that the phase shifter 6 in the antenna system 100 does not block the antenna beam. The following will expand on the integration method of the phase shifter 6 and the feeding network 7 on the frequency selective surface 5 in combination with the frequency selective surface structure 200.

[0160] See also Figure 9-10b , Fig. 9 A schematic diagram of the structure of a frequency selective surface according to an embodiment of the present application; Fig.10a This is a structural schematic diagram of another implementation of the frequency selective surface structure of the embodiment of the present application; Fig.10b for Fig.10a Schematic diagram of the local connection structure of part A.

[0161] like Figure 9-10bAs shown, the frequency selective surface structure 200 includes a frequency selective surface 5, a feeding network 7 and a phase shifter 6. The frequency selective surface 5 includes a metal layer 51, the phase shifter 6 is electrically connected to the feeding network 7, and the phase shifter 6 and the feeding network 7 are integrated into the metal layer 51 of the frequency selective surface 5.

[0162] The frequency selective surface structure 200 provided in the embodiment of the present application can be applied in the antenna system 100, and the phase shifter 6 and the feeding network 7 are integrated on the metal layer 51 of the frequency selective surface 5. The metal layer 51 of the frequency selective surface 5 has a spatial filter characteristic. By changing the wave transmission characteristic of the antenna through the design of the metal layer 51, the demand for antenna electromagnetic wave transmission regulation can be met. The frequency selective surface 5 can be designed to have a completely transparent effect on part of the antenna (for example, the second antenna 2 in the antenna system 100), that is, a structure that is electromagnetically transparent to this part of the antenna. The phase shifter 6 and the feeding network 7 are integrated on the metal layer 51, and the metal layer 51 has a stealth effect on the phase shifter 6. If a miniaturized phase shifter 6 is used, the phase shifter 6 can be completely hidden on one side of the metal layer 51, and the metal layer 51 also has the same stealth effect on the transmission line structure 71 in the feeding network 7, and the feeding network 7 and the phase shifter 6 will not affect the filtering characteristics of the frequency selective surface structure 200. In this way, the frequency selective surface structure 200 composed of the frequency selective surface 5, the phase shifter 6 and the feeding network 7 can still produce an electromagnetic transparent effect on part of the antenna, so as not to block the beam of the antenna. Another part of the antenna (such as the first antenna 1 and the third antenna 3 in the antenna system 100) can be set on the other side of the frequency selective surface structure 200, so that its electromagnetic waves radiate in the direction away from the frequency selective surface structure 200, and the phase shifter 6 will not block the beam of this part of the antenna. Furthermore, since the phase shifter 6 and the feeding network 7 are integrated together and have a compact structure, the length of the transmission line structure 71 in the feeding network 7 can be shortened, reducing transmission losses.

[0163] Therefore, the frequency selective surface structure 200 provided in the embodiment of the present application can reduce transmission loss when the phase shifter 6 does not block the antenna beam, and can take into account both the coverage range and transmission quality of the antenna signal, thereby solving the problem of difficult layout of the phase shifter 6 in the multi-band integrated antenna system 100.

[0164] It will be understood by those skilled in the art that the specific shape of the metal layer 51 is not limited. In one embodiment, the metal layer 51 has a metal area 513, and a hollow area 514 is formed around the metal area 513. The feed network 7 and the phase shifter 6 are integrated in the metal area 513, and the projections of the feed network 7 and the phase shifter 6 along the first direction z to the metal layer 51 are located in the metal area 513 as a whole. Among them, the metal layer 51 is located in a plane perpendicular to the first direction z, and the first direction z is perpendicular to the plane where the metal layer 51 is located. Or it can be understood that the metal layer 51 is a layered structure made of metal material as a whole, and some areas of the layered structure are hollowed out and processed to form a specific metal pattern. The hollowed-out part constitutes the hollowed-out area 514, and the remaining solid structure part is the metal area 513.

[0165] The phase shifter 6 and the feed network 7 are integrated on the metal area 513 and carried by the metal area 513. The projection of the feed network 7 and the phase shifter 6 to the metal layer 51 along the first direction z is located in the metal area 513 as a whole. It can be understood that the phase shifter 6 and the feed network 7 are not overlapped with the hollow area 514 in the first direction z, so as to prevent the phase shifter 6 and the feed network 7 from blocking the antenna beam (for example, blocking the beam of the second antenna 2 in the antenna system 100). It should be noted that the projection of the feed network 7 and the phase shifter 6 to the metal layer 51 along the first direction z is not absolutely located in the metal area 513, and a certain deviation is allowed, for example, a small part may exceed the metal area 513. Although the part exceeding the metal area 513 will also block the antenna beam to a certain extent, when the exceeding part is small enough, the antenna beam is not obviously blocked, and its influence on the antenna pattern can be ignored, and the effect of reducing the transmission loss can also be achieved when the phase shifter 6 does not block the antenna beam.

[0166] Those skilled in the art will appreciate that the specific shape of the metal layer 51 is not limited. For example, the metal region 513 in the metal layer 51 may be in a grid shape, a patch shape, a gap shape, etc. Fig. 9 As shown, in one embodiment, the metal layer 51 includes a metal grid 5131, the metal grid 5131 constitutes a metal area 513, and the space surrounded by each grid in the metal grid 5131 together constitutes a hollow area 514. The grid-shaped frequency selective surface 5 has a relatively regular shape and is easy to process, and the grid lines in the grid are convenient for wiring. Figure 10a-Figure 10bAs shown, in one embodiment, the frequency selective surface 5 can also be formed by a metal grid + metal patch, and a metal patch 5132 is provided in each grid of the metal grid 5131, and the metal grid 5131 and the metal patch 5132 together constitute the metal area 513, and the gap between the metal patch 5132 and the metal grid 5131 together constitutes the hollow area 514. The shape of the metal patch 5132 is not limited, for example, it can be circular, square, triangular, etc. In one embodiment, the shape of the metal patch 5132 is square.

[0167] In one embodiment, the frequency selective surface structure 200 further includes a dielectric layer (not shown in the figure), and the metal layer 51 is installed on the dielectric layer. The dielectric layer can be used to support the metal layer 51. For example, the metal layer 51 can be mounted on the surface of the dielectric layer, or the metal layer 51 can be embedded in the dielectric layer. The hollow area 514 of the metal layer 51 can also be filled with a dielectric. The dielectric layer is made of non-metallic material, such as glass, ceramic, etc., and is not specifically limited. It can be understood by those skilled in the art that the shape and position of the dielectric layer are not limited, as long as it can provide support for the metal layer 51. In an example scenario, when the frequency selective surface 5 includes a first metal layer 511 and a second metal layer 512, the dielectric layer can be a plurality of non-metallic support members arranged between the first metal layer 511 and the second metal layer 512.

[0168] As mentioned above, the number of phase shifters 6 in the frequency selective surface 5 and the number of transmission line structures 71 in the feed network 7 are not limited, and can be one or more. When there are multiple radiators in the antenna, a phase shifter 6 and multiple transmission line structures 71 can be set in the frequency selective surface structure 200, and one phase shifter 6 can be electrically connected to all the transmission line structures 71 in the multiple transmission line structures 71, and then electrically connected to all radiators in the antenna through each transmission line structure 71. Alternatively, multiple phase shifters 6 can also be set, each phase shifter 6 is electrically connected to a part of the transmission line structure 71, and then electrically connected to some radiators in the antenna through each transmission line structure 71, and the present application does not limit this.

[0169] For ease of understanding, two scenarios are listed below as illustrations.

[0170] like Figure 9-10b As shown, taking the dual-polarized first antenna 1 in the antenna system 100 as an example, the figure shows four radiators 10 arranged along the second direction y, and the four radiators 10 constitute a row of radiators 10. Fig. 9As shown, in an example scenario, the frequency selective surface structure 200 includes two phase shifters 6, which are distributed on both sides of a column of radiators in the third direction x, and each phase shifter 6 is electrically connected to four radiators 10 through four transmission line structures 71 to adjust the phases of the four radiators 10. Fig.10a As shown, in another example scenario, the frequency selective surface structure 200 includes four phase shifters 6, and two phase shifters 6 are distributed on both sides of a column of radiators 10 in the third direction x. Fig.10a Among the two phase shifters 6 on the middle left side, the upper phase shifter 6 is electrically connected to the two radiators 10 through two transmission line structures 71 to adjust the phases of the two radiators 10, and the lower phase shifter 6 is electrically connected to the other two radiators 10 through two transmission line structures 71 to adjust the phases of the other two radiators 10. Fig.10a The layout of the two phase shifters 6 on the right side of the middle is symmetrical with the layout of the two phase shifters 6 on the left side, and will not be described in detail here.

[0171] Those skilled in the art will appreciate that there is no limitation on the connection method between the transmission line structure 71 and the radiator. Fig.10b As shown, in one embodiment, the transmission line structure 71 is electrically connected to the radiator 10 through a feeder 72, one end of the feeder is connected to the transmission line structure 71, and the other end is connected to the radiator 10. The specific form of the feeder is not limited, for example, it can be a conductive structure such as a cable, a conductive member, or a metal via on a printed circuit board.

[0172] It can be understood by those skilled in the art that Figure 9-10b The two scenarios are only examples and do not constitute specific limitations to the present application.

[0173] Those skilled in the art can understand that the present application does not limit the type and specific structure of the phase shifter 6, for example, it can be a physical mechanical phase shifter, an electronic solid-state phase shifter, a liquid crystal phase shifter, or a switch-switched phase shifter, etc. However, since the local size of the metal area 513 on the metal layer 51 is limited, in order to avoid the phase shifter 6 blocking the antenna signal, a miniaturized phase shifter 6 should be used as much as possible, and the phase shifter 6 should have some connection structures for installation on the metal layer 51. The following is an example of the structure that can be used for the phase shifter 6 in conjunction with the accompanying drawings.

[0174] See also Figure 11a-Figure 12c , Fig.11a This is a schematic structural diagram of a phase shifter in a frequency selective surface structure according to an embodiment of the present application; Fig.11b A schematic structural diagram of another implementation of a phase shifter in a frequency selective surface structure according to an embodiment of the present application; Figure 12a-12c This is a schematic diagram of the connection between the phase shifter and the metal layer in the frequency selective surface structure according to an embodiment of the present application.

[0175] like Figure 11a-Figure 11b As shown, in one embodiment, the phase shifter 6 includes an outer conductor 63, a fixed medium 64, a sliding medium 65 and at least one signal line winding 66. A receiving cavity is formed in the outer conductor 63, and the fixed medium 64, the sliding medium 65 and at least one signal line winding 66 are all received in the receiving cavity. The fixed medium 64 is fixedly connected to the outer conductor 63, and the sliding medium 65 is located between the fixed medium 64 and the outer conductor 63, and is slidably connected to the fixed medium 64. Each signal line winding 66 is wound and fixed on the fixed medium 64, and each signal line winding 66 is located between the fixed medium 64 and the sliding medium 65, and the phase shifter 6 is electrically connected to the feed network 7 through each signal line winding 66. At least a portion of the outer conductor 63 is set as a planar structure, and the phase shifter 6 is fixedly connected to the metal layer 51 through the planar structure.

[0176] Among them, the outer conductor 63 is the shell of the phase shifter 6, which is made of metal. In one embodiment. The outer conductor 63 is electrically connected to the metal layer 51 to achieve grounding of the phase shifter 6. The signal line winding 66 is electrically connected to the feed network 7, and then electrically connected to the radiator of the antenna through the transmission line structure 71 in the feed network 7. The specific number of signal line windings 66 is not limited. In an example scenario, a phase shifter 6 is electrically connected to four radiators, and four signal line windings 66 are correspondingly arranged in the phase shifter 6, and each signal line winding 66 is correspondingly connected to one radiator through the transmission line structure 71.

[0177] It should be noted that when a phase shifter 6 is electrically connected to multiple radiators, the multiple radiators electrically connected to the phase shifter 6 may be radiators of antennas in the same frequency band or radiators of antennas in different frequency bands. For example, a phase shifter 6 may be electrically connected to the radiator 10 of the first antenna 1 and the radiator 30 of the third antenna 3 at the same time, and the present application does not limit this.

[0178] It should be noted that a phase shifter 6 may have multiple input terminals 61 and multiple output terminals 62, and this application does not limit this. In one embodiment, there are multiple signal line windings 66 in the phase shifter 6, and the multiple signal line windings 66 constitute at least one group of signal line windings, and each group of signal line windings includes at least one signal line winding 66. In each group of signal line windings, one end of each signal line winding 66 is connected to form an input terminal 61 of the phase shifter 6, and the other end of each signal line winding 66 constitutes at least one output terminal 62 of the phase shifter 6, and each of the at least one output terminal 62 is electrically connected to the corresponding transmission line structure 71. Among them, the number of groups of signal line windings in the phase shifter 6 and the number of signal line windings 66 in each group of signal line windings are not limited. For example, a phase shifter 6 may include 1, 2, 3 or more groups of signal line windings, each group of signal line windings may include 1, 2, 3 or more signal line windings 66, and each group of signal line windings may correspond to the radiator of an antenna connected to a frequency band.

[0179] For example, Fig. 9 In the illustrated scenario, a group of signal line windings is provided in each phase shifter 6, and the group of signal line windings includes four signal line windings 66, one end of the four signal line windings 66 is connected to form the input end 61 of the phase shifter 6, and the other ends of the four signal line windings 66 respectively form four output ends 62 of the phase shifter 6 (two of the output ends 62 are integrated in the same outlet on the phase shifter 6, so only three output ends 62 are marked in the figure), and each of the four output ends 62 is electrically connected to a transmission line structure 71 and electrically connected to a corresponding radiator. The input end 61 of the phase shifter 6 is also electrically connected to a transmission line structure 71, and the transmission line structure 71 can be connected to other components in the antenna system 100 or the base station 300, such as a radio frequency module, a power supply circuit, etc. In one embodiment, the input end 61 of the phase shifter 6 is electrically connected to the radio frequency module 8 of the base station 300 through the transmission line structure 71.

[0180] In another example scenario, the phase shifter 6 may also include two groups of signal line windings, one of the two groups of signal line windings is electrically connected to the multiple radiators 10 of the first antenna 1 through multiple signal line windings 66, and the other group of signal line windings is electrically connected to the multiple radiators 30 of the third antenna 3 through multiple signal line windings 66. One end of each signal line winding 66 in the group of signal line windings electrically connected to the first antenna 1 is connected to form an input end 61 of the phase shifter 6, and one end of each signal line winding 66 in the other group of signal line windings electrically connected to the third antenna 3 is connected to form another input end 61 of the phase shifter 6. The two input ends 61 of the phase shifter 6 can be electrically connected to different RF modules or different ports of the same RF module through different transmission line structures.

[0181] Furthermore, the fixed medium 64 is fixed relative to the outer conductor 63, the signal line winding 66 is fixed on the fixed medium 64, and the sliding medium 65 covers the surface of the signal line winding 66 and can slide on the surface of the signal line winding 66. The principle of the phase shifter 6 adjusting the phase of the radiator is: changing the position of the sliding medium 65 can change the range of each signal line winding 66 covered by the sliding medium 65, and the part of the signal line winding 66 not covered by the sliding medium 65 is exposed to the air, so that the electrical length of the signal line winding 66 changes, thereby changing the phase shift amount of the radiator corresponding to each signal line winding 66.

[0182] When the phase shifter 6 adopts the above structure, multiple signal wires are wound together on the fixed medium 64, and different signal wire windings 66 can be set as a bent structure in the phase shifter 6, so that multiple signal wire windings 66 are concentrated in a small area, so the structure of the phase shifter 6 is relatively compact and the volume is relatively small. The fixed medium 64 and the sliding medium 65 of the phase shifter 6 can also be made of a material with a high dielectric constant, which can further reduce the volume of the phase shifter 6. Alternatively, a large number of phase shifters 6 can be arranged in the frequency selective surface structure 200, and fewer signal wire windings 66 (for example, 1 or 2) are set in each phase shifter 6, which can also reduce the volume of the phase shifter 6.

[0183] Those skilled in the art will appreciate that the specific shape of the outer conductor 63 is not limited. For ease of description, the portion where the phase shifter 6 is connected to the metal layer 51 is defined as the bottom 63a of the outer conductor 63. Fig.11a As shown, in one embodiment, the bottom 63a is configured as a planar structure as a whole, so that the outer conductor 63 forms a closed structure as a whole, and the fixing medium 64 can be fixed on the bottom 63a. Fig.11b As shown, in an alternative embodiment, the bottom 63a of the outer conductor 63 may also be provided with an opening, so that the outer conductor 63 forms a semi-enclosed structure with an opening, and the fixing medium 64 may be fixedly connected to the side walls on both sides of the opening. The bottom 63a of the outer conductor 63 is fixedly connected to the metal layer 51, for example, it may be fixedly connected to the grid lines in the metal grid 5131. When the width d1 of the phase shifter 6 is less than or equal to the width w of the grid lines (see Figure 9-10a ), the projection of the phase shifter 6 on the metal layer 51 along the first direction z is entirely located within the metal region 513 and will not block the antenna beam.

[0184] Those skilled in the art can understand that when the phase shifter 6 is fixed to the metal layer 51 and the outer conductor 63 is electrically connected to the metal layer 51, the specific fixing method of the phase shifter 6 on the metal layer 51 is not limited, and the phase shifter 6 can be directly fixedly connected to the metal layer 51 or indirectly fixedly connected to the metal layer 51. Fig.12aAs shown, in one embodiment, the phase shifter 6 is connected to the metal layer 51 in direct current, and the bottom 63a of the outer conductor 63 is in contact with the metal layer 51 as a whole. For example, the outer conductor 63 can be welded to the metal layer 51 as a whole, and the connection is more secure. Figure 12b As shown, in an alternative embodiment, the phase shifter 6 can also be connected to the metal layer 51 in sections by direct current, and only a portion of the bottom 63a of the outer conductor 63 is in contact with the metal layer 51. For example, several welding points can be arranged at intervals along the grid lines of the metal grid 5131, and the phase shifter 6 is welded to the metal layer 51 only at the positions of the welding points, which is relatively simple to operate and can save manpower. Fig.12c As shown, in another alternative embodiment, the phase shifter 6 is coupled to the metal layer 51. It can be understood that the phase shifter 6 is not in direct contact with the metal layer 51, and an insulating support such as a plastic buckle can be provided between the two. The phase shifter 6 is fixed to the metal layer 51 through the insulating support, and can be electrically connected to the metal layer 51 through current coupling and other methods. In addition to the above three connection methods, the phase shifter 6 can also be fixed to the metal layer 51 and electrically connected to the metal layer 51 in other ways, which are not listed here one by one.

[0185] Those skilled in the art will appreciate that the specific type and structure of the transmission line structure 71 in the feeding network 7 are not limited, and may be, for example, a microstrip line, a coaxial cable, etc. Several possible structures are described below with reference to the accompanying drawings.

[0186] See also Figure 13a-Figure 20c , Figure 13a-Figure 13b-2 This is a structural schematic diagram of a first implementation mode of a first transmission line structure in a frequency selective surface structure of an embodiment of the present application, wherein: Figure 13b-1 for Fig.13a Cross-sectional view along the BB direction, Figure 13b-2 for Fig.13a Cross-section view in the CC direction; Fig.14a This is a structural schematic diagram of a second implementation mode of the first transmission line structure in the frequency selective surface structure of an embodiment of the present application; Fig.14b It is a structural schematic diagram of a third implementation mode of the first transmission line structure in the frequency selective surface structure of an embodiment of the present application; Figure 15a-Figure 15b-2 This is a structural schematic diagram of a fourth implementation mode of the first transmission line structure in the frequency selective surface structure of an embodiment of the present application, wherein: Figure 15b-1 for Fig.15a Cross-section along the mid-DD direction; Figure 15b-2 for Fig.15a Cross-section along the EE direction; Figure 16a-16b This is a structural schematic diagram of the fifth implementation mode of the first transmission line structure in the frequency selective surface structure of the embodiment of the present application, wherein: Fig.16b for Fig.16a Cross-sectional view in the FF direction; Fig.17It is a structural schematic diagram of a sixth implementation mode of the first transmission line structure in the frequency selective surface structure of an embodiment of the present application; Fig.18 This is a structural schematic diagram of a seventh implementation mode of the first transmission line structure in the frequency selective surface structure of an embodiment of the present application; Fig.19 This is a schematic diagram of the structure of a power divider in a frequency selective surface structure according to an embodiment of the present application; Figure 20a-Figure 20c This is a schematic diagram of the connection between the transmission line structure and the metal layer in the frequency selective surface structure according to an embodiment of the present application.

[0187] like Figure 13a-Figure 18 As shown, in one embodiment, the plurality of transmission line structures 71 in the feed network 7 may include a first transmission line structure 711. The first transmission line structure 711 is a linear structure as a whole, which extends along the grid lines of the metal grid 5131 in the metal layer 51. When the width d2 of the first transmission line structure 711 is less than the width w of the grid line (see Figure 9-10b ), the projection of the first transmission line structure 711 along the first direction z on the metal layer 51 is entirely located within the metal region 513, thereby avoiding blocking the antenna beam.

[0188] In one embodiment, the first transmission line structure 711 includes an outer conductor 7111 and a core 7112, wherein the core 7112 is enclosed in a cavity 7110 inside the outer conductor 7111, and a gap 7113 is provided between the core 7112 and the outer conductor 7111. The outer conductor 7111 is a shell of the first transmission line structure 711, the core 7112 is used to transmit signals, and the gap 7113 indicates that the medium between the outer conductor and the core 7112 is air. With this structure, the core 7112 is suspended as a whole in the cavity 7110 of the outer conductor 7111, and the core 7112 is surrounded by the air in the cavity 7110, and the dielectric constant of the air is small, which can reduce the transmission loss of the first transmission line structure 711. In one embodiment, the first transmission line structure 711 further includes a plurality of support members 7114 disposed between the outer conductor 7111 and the core 7112, the plurality of support members 7114 being disposed at intervals along the extension direction of the core 7112, and the core 7112 being fixedly connected to the outer conductor 7111 via the plurality of support members 7114. The specific form of the support member 7114 is not limited, and for example, it may be a dielectric structural member.

[0189] Furthermore, at least part of the outer conductor 7111 is configured as a planar structure, and the first transmission line structure 711 is fixedly connected to the metal layer 51 via the planar structure. In one embodiment, the outer conductor 7111 is also electrically connected to the metal layer 51 to achieve grounding of the first transmission line structure 711.

[0190] Those skilled in the art will appreciate that the shape of the outer conductor 7111 and the shape of the core 7112 are not limited. For ease of description, the portion where the outer conductor is connected to the metal layer 51 is defined as the bottom 7111a of the outer conductor. Figure 13a-Figure 13b-2 , Figure 15a-Figure 15b-2 , Fig.17 As shown, in one embodiment, the outer conductor 7111 is a semi-enclosed structure, and an opening is provided at a position opposite to the bottom 7111a in the first direction z. Fig.14b As shown, in an alternative embodiment, the bottom 7111a of the outer conductor 7111 may also be provided with an opening, so that the outer conductor 7111 forms a semi-enclosed structure. Fig.14a , Figure 16a-16b As shown, in other alternative embodiments, the outer conductor 7111 may also be a closed structure.

[0191] In one embodiment, the core 7112 is configured as a linear structure with a rectangular cross section. Figure 13b-1 , Figure 13b-2 , Fig.14a , Figure 15b-1 , Figure 15b-2 , Fig.18 As shown, in one embodiment, the long side of the rectangle is arranged vertically, that is, the long side of the rectangle is perpendicular to the bottom 7111a of the outer conductor 7111. Fig.14b , Figure 16a-16b , Fig.17 As shown, in an alternative embodiment, the long side of the rectangle is arranged horizontally, that is, the long side of the rectangle is parallel to the bottom 7111 a of the outer conductor 7111 .

[0192] Those skilled in the art will appreciate that in the first transmission line structure 711, the outer conductor 7111 may have one or more cavities 7110, and may also have one or more cores 7112, without any specific limitation. Figure 13a-Figure 14b As shown, in one embodiment, the first transmission line structure 711 includes a core 7112, an outer conductor 7111 has a cavity 7110, and the core 7112 is disposed in the cavity 7110. Figure 15a-Figure 16b As shown, in one embodiment, the first transmission line structure 711 includes two cores 7112, and there is a cavity 7110 in the outer conductor 7111. The two cores 7112 are arranged in the same cavity 7110 at intervals, and there is a gap between adjacent cores 7112. Figure 17-Figure 18 As shown, in one embodiment, the first transmission line structure 711 includes three cores 7112, and the outer conductor 7111 has three cavities 7110, and the three cores 7112 are respectively located in different cavities 7110. The three cavities 7110 can be interconnected (such as Fig.17), or they can be independent of each other (such as Fig.18 ), this application does not limit this.

[0193] like Fig.19 As shown, in one embodiment, the plurality of transmission line structures 71 in the feed network 7 may further include a second transmission line structure, and the second transmission line structure is configured as a power divider 712. The power divider 712 includes a conductive shell 7121 and a battery cell 7122, the battery cell 7122 is enclosed in a cavity 7110 inside the conductive shell 7121, and a gap 7123 is provided between the battery cell 7122 and the conductive shell 7121. At least a portion of the conductive shell 7121 is configured as a planar structure, and the power divider 712 is fixedly connected to the metal layer 51 through the planar structure. Among them, the conductive shell 7121 of the power divider 712 has the same function as the outer conductor in the first transmission line structure 711, and the battery core 7122 of the power divider 712 has the same function as the core 7112 in the first transmission line structure 711. There is a gap 7123 between the battery core 7122 and the conductive shell 7121, that is, the battery core 7122 is suspended in the conductive shell 7121 and surrounded by air to reduce the transmission loss of the power divider 712.

[0194] In one embodiment, the power divider 712 further includes a plurality of support members disposed between the conductive housing 7121 and the battery cell 7122, and the plurality of support members are disposed at intervals to partially support the battery cell 7122 in the conductive housing 7121. The specific form of the support member is not limited, and may be, for example, a dielectric structural member.

[0195] Different from the first transmission line structure, the battery cell 7122 has an input terminal 7122a and multiple output terminals 7122b. The specific number of output terminals is not limited. In one embodiment, the battery cell 7122 has one input terminal 7122a and two output terminals 7122b. The signal is input into the power divider 712 from the input terminal 7122a, and is divided into two paths inside the power divider 712, and is output from the two output terminals 7122b respectively. The conductive shell 7121 can be designed as a "T-shaped" structure with three openings. The input terminal 7122a and the output terminal 7122b of the battery cell 7122 extend out of the conductive shell 7121 from the three openings respectively and are electrically connected to other components. In one embodiment, the input terminal 7122a of the battery cell 7122 can be connected to the phase shifter 6, and the output terminal 7122b can be connected to other transmission line structures 71. Alternatively, the input end 7122a and the output end 7122b of the battery cell 7122 may also be connected to other transmission line structures, etc., and the present application does not impose any limitation on this.

[0196] In a more popular understanding, the first transmission line structure 711 is a linear structure with two ports, one of which serves as an input port and the other as an output port. The power divider 712 can be regarded as merging multiple first transmission line structures 711 to form a transmission line structure 71 with more than two ports, one or more of which can serve as input ports 7122a, and the remaining ports can serve as output ports 7122b, and this application does not impose any restrictions on this. In an example scenario, the battery cell 7122 of the power divider 712 can also have one output port 7122b and multiple input ports 7122a, so that multiple signals can be merged into one.

[0197] Those skilled in the art will appreciate that the transmission line structure 71 is fixed to the metal layer 51 and can be grounded through the metal layer 51 (for example, the outer conductor in the first transmission line structure 711 is electrically connected to the metal layer 51, and the conductive shell 7121 of the power divider 712 is electrically connected to the metal layer 51). The specific fixing method of the transmission line structure 71 on the metal layer 51 is not limited, and the transmission line structure 71 can be directly fixedly connected to the metal layer 51 or indirectly fixedly connected to the metal layer 51.

[0198] like Fig.20a As shown, in one embodiment, the transmission line structure 71 is connected to the metal layer 51 in direct current. Fig.20b As shown, in one embodiment, the transmission line structure 71 may also be connected to the metal layer 51 in a segmented direct current manner. Fig.20c As shown, in one embodiment, the transmission line structure 71 is coupled to the metal layer 51. The definitions of DC connection, segmented DC connection, and coupled connection are the same as the connection between the phase shifter 6 and the metal layer 51 described above, and are not repeated here.

[0199] The above specifically describes the functions and structures of the various components in the antenna system 100 and the frequency selective surface structure 200 of the present application. It can be understood by those skilled in the art that the antenna system 100 is not limited in the formation method. For example, each component in the antenna system 100 can be produced separately and then assembled. In one embodiment, the antenna system 100 is formed on a printed circuit board. Specifically, the printed circuit board has a metal structure and a non-metal structure. For example, the printed circuit board can include a plurality of stacked metal layers and a plurality of dielectric layers arranged between adjacent metal layers. The metal layers can be connected by metal vias penetrating the dielectric layers. Each metal layer and the metal via constitute the metal structure of the printed circuit board, and the plurality of dielectrics constitute the dielectric structure of the printed circuit board. In one embodiment, at least part of the metal structure constitutes the metal material components such as the floor 4, the radiators of each antenna, and the metal layer 51 of the frequency selective surface 5 in the antenna system 100 (that is, the above components are directly processed and formed on the metal structure of the printed circuit board). At least part of the dielectric structure of the printed circuit board constitutes the non-metallic components such as the dielectric layer of the frequency selective surface structure 200 (that is, the dielectric layer is directly processed and formed in the dielectric structure of the printed circuit board). In other alternative implementations, the antenna system 100 may also be manufactured by other methods, which are not listed here one by one.

[0200] See also Fig.21 , Fig.21 This is a schematic diagram of the structure of a base station according to an embodiment of the present application.

[0201] like Fig.21As shown, the present application also provides a base station 300, including an antenna system 100 and a radio frequency module 8 connected to the antenna system 100. The base station 300 provided in the present application can be a device for communicating with a terminal device, including a base transceiver station (BTS) in a global system for mobile communications (GSM) system or a code division multiple access (CDMA), or a node B (NB) in a wideband code division multiple access (WCDMA) system, or an evolved Node B (eNB or eNodeB) in an LTE system, or a wireless controller in a cloud radio access network (CRAN) scenario, or the base station 300 can include a relay station, an access point, a vehicle-mounted device, a wearable device, a base station in a future 5G network, or a base station in a future evolved public land mobile network (PLMN) network, etc., and the embodiments of the present application are not limited. Antennas of multiple frequency bands can be combined in the base station 300, and the base station 300 has a high overall integration level, a wide signal coverage range, and fewer signal blind spots.

[0202] The RF module 8 can complete the conversion between the air RF channel and the baseband digital channel, as well as the amplification, transceiver and other functions of the RF channel, and its specific type is not limited. In addition to the RF module 8, the base station 300 may also include other components, such as a power supply circuit for powering the antenna, etc., which is not limited in this application.

[0203] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A frequency selective surface structure, characterized in that: It comprises a frequency selective surface, a feeding network and a phase shifter; the frequency selective surface comprises a metal layer, the phase shifter is electrically connected to the feeding network, and the phase shifter and the feeding network are integrated into the metal layer of the frequency selective surface.

2. The frequency selective surface structure according to claim 1, characterized in that: The metal layer has a metal area, and a hollow area is formed around the metal area; the feeding network and the phase shifter are integrated in the metal area, and the projections of the feeding network and the phase shifter to the metal layer along a first direction are located in the metal area as a whole; wherein the first direction is perpendicular to the plane where the metal layer is located.

3. The frequency selective surface structure according to claim 2, characterized in that: The metal layer includes a metal grid, the metal grid constitutes the metal area, and the space surrounded by each grid in the metal grid together constitutes the hollow area.

4. The frequency selective surface structure according to claim 2, characterized in that: The metal layer includes a metal grid and a plurality of metal patches, wherein the plurality of metal patches are correspondingly arranged in a plurality of grids of the metal grid; the metal grid and the metal patches constitute the metal area, and the gap between the metal patches and the metal grid constitutes the hollow area.

5. The frequency selective surface structure according to any one of claims 1 to 4, characterized in that: The frequency selective surface includes multiple metal layers stacked in a first direction and arranged parallel to each other, and the feeding network and the phase shifter are integrated on at least one metal layer of the multiple metal layers; wherein the first direction is perpendicular to the plane where the metal layers are located.

6. The frequency selective surface structure according to claim 5, characterized in that: The plurality of metal layers include two metal layers, each of the two metal layers includes two surfaces opposite to each other in the first direction, and the feeding network and the phase shifter are integrated on any one or more surfaces of the two metal layers.

7. The frequency selective surface structure according to any one of claims 1 to 6, characterized in that: The feed network includes a plurality of transmission line structures, and: The frequency selective surface structure includes one phase shifter, and one phase shifter is electrically connected to all transmission line structures of the plurality of transmission line structures; Alternatively, the frequency selective surface structure includes a plurality of the phase shifters, and each of the plurality of phase shifters is electrically connected to a portion of the transmission line structures of the plurality of transmission line structures.

8. The frequency selective surface structure according to claim 7, characterized in that: The phase shifter comprises an outer conductor, a fixed medium, a sliding medium and at least one signal line winding, wherein a receiving cavity is formed in the outer conductor, and the fixed medium, the sliding medium and the at least one signal line winding are all received in the receiving cavity; The fixed medium is fixedly connected to the outer conductor, the sliding medium is located between the fixed medium and the outer conductor, and is slidably connected to the fixed medium; each signal line winding in the at least one signal line winding is wound and fixed to the fixed medium, and each signal line winding is located between the fixed medium and the sliding medium, and the phase shifter is electrically connected to the feeding network through each signal line winding; At least a portion of the outer conductor is configured as a planar structure, and the phase shifter is fixedly connected to the metal layer via the planar structure.

9. The frequency selective surface structure according to claim 8, characterized in that: The at least one signal line winding is a plurality of signal line windings, the plurality of signal line windings constitute at least one group of signal line windings, and each group of signal line windings in the at least one group of signal line windings includes at least one signal line winding; In each group of signal line windings, the at least one signal line winding is one signal line winding or at least two signal line windings, one end of the one signal line winding or one end of the at least two signal line windings are connected to form an input end of the phase shifter, and the other end of the at least one signal line winding constitutes at least one output end of the phase shifter, and each of the at least one output end is electrically connected to the corresponding transmission line structure.

10. The frequency selective surface structure according to any one of claims 7 to 9, characterized in that: The plurality of transmission line structures include at least one first transmission line structure, each of the at least one first transmission line structure includes an outer conductor and a core, the core is wrapped in a cavity inside the outer conductor, and there is a gap between the core and the outer conductor; At least a portion of the outer conductor is configured as a planar structure, and the first transmission line structure is fixedly connected to the metal layer via the planar structure.

11. The frequency selective surface structure according to claim 10, characterized in that: The first transmission line structure further includes a plurality of support members disposed between the outer conductor and the core body, the plurality of support members being disposed at intervals along an extension direction of the core body, and the core body being fixedly connected to the outer conductor via the plurality of support members.

12. The frequency selective surface structure according to claim 10 or 11, characterized in that: The first transmission line structure comprises a plurality of cores arranged at intervals, and: The outer conductor has a cavity, and the plurality of cores are located in the cavity; Alternatively, the outer conductor has a plurality of cavities that are interconnected, the plurality of cavities correspond one-to-one to the plurality of cores, and each core is located in a corresponding cavity.

13. The frequency selective surface structure according to any one of claims 7 to 12, characterized in that: The plurality of transmission line structures include at least one second transmission line structure, each of the at least one second transmission line structure is configured as a power divider, the power divider includes a conductive shell and a battery core, the battery core is wrapped in a cavity inside the conductive shell, and there is a gap between the battery core and the conductive shell; the battery core has an input end and a plurality of output ends, and the input end of the battery core is electrically connected to the phase shifter; At least a portion of the conductive housing is configured as a planar structure, and the second transmission line structure is fixedly connected to the metal layer via the planar structure.

14. The frequency selective surface structure according to claim 13, characterized in that: When the phase shifter comprises an outer conductor, the outer conductor of the phase shifter is electrically connected to the metal layer; When the feed network comprises a plurality of transmission line structures, the plurality of transmission line structures comprises at least one first transmission line structure, and each of the at least one first transmission line structure comprises an outer conductor, the outer conductor of each of the first transmission line structures is electrically connected to the metal layer; When the feed network comprises a plurality of transmission line structures, the plurality of transmission line structures comprises at least one second transmission line structure, and each of the at least one second transmission line structure comprises a conductive shell, the conductive shell of each of the second transmission line structures is electrically connected to the metal layer; The electrical connection mode is any one of the following: coupling connection, direct current connection or segmented direct current connection.

15. The frequency selective surface structure according to any one of claims 1 to 14, characterized in that: The frequency selective surface structure further includes a dielectric layer, and the metal layer is mounted on the dielectric layer.

16. An antenna system, comprising a floor, a plurality of antennas stacked in a first direction, and a plurality of feeding networks for feeding the plurality of antennas, wherein the floor is arranged on one side of the plurality of antennas in the first direction, characterized in that: The antenna system also includes a frequency selective surface structure as described in any one of claims 1-15; the frequency selective surface structure is arranged between adjacent antennas stacked in the multiple antennas, and the feeding network of the frequency selective surface structure constitutes a feeding network of at least one antenna away from the floor among the adjacent antennas stacked.

17. The antenna system according to claim 16, characterized in that The plurality of antennas include a first antenna and a second antenna stacked in the first direction, the floor is arranged on a side of the second antenna away from the first antenna, and the frequency selective surface structure is arranged between the first antenna and the second antenna; The first antenna and the second antenna both include a plurality of radiators distributed in an array, and at least a portion of the feeding network of the frequency selective surface structure constitutes the feeding network of the first antenna and is electrically connected to the plurality of radiators of the first antenna to feed the plurality of radiators of the first antenna.

18. The antenna system according to claim 17, characterized in that When the frequency selective surface structure includes two metal layers, the feeding network and the phase shifter of the frequency selective surface structure are integrated on a metal layer far away from the second antenna among the two metal layers.

19. The antenna system according to claim 17 or 18, characterized in that: The plurality of radiators of the first antenna constitute at least one column of radiators, and each column of the at least one column of radiators includes at least two radiators spaced apart along the second direction; When the feeding network of the frequency selective surface structure includes multiple transmission line structures, the transmission line structures are symmetrically distributed on both sides of each column of radiators in the third direction, and the phase shifters are symmetrically distributed on both sides of each column of radiators in the third direction; wherein the first direction, the second direction, and the third direction are perpendicular to each other.

20. The antenna system according to any one of claims 17 to 19, characterized in that: The multiple antennas further include a third antenna, which is disposed on a side of the frequency selective surface structure away from the floor; the third antenna includes a plurality of radiators distributed in an array, and the plurality of radiators of the third antenna and the plurality of radiators of the first antenna are alternately arranged in a plane perpendicular to the first direction; At least a portion of the feeding network of the frequency selective surface structure constitutes a feeding network of the third antenna and is electrically connected to a plurality of radiators of the third antenna to feed the plurality of radiators of the third antenna.

21. The antenna system according to claim 20, characterized in that The plurality of radiators of the third antenna constitute at least one column of radiators, and each column of the at least one column of radiators includes at least two radiators spaced apart along the second direction; When the feeding network of the frequency selective surface structure includes multiple transmission line structures, the transmission line structures are symmetrically distributed on both sides of each column of radiators in the third direction, and the phase shifters are symmetrically distributed on both sides of each column of radiators in the third direction; wherein the first direction, the second direction, and the third direction are perpendicular to each other.

22. The antenna system according to claim 20 or 21, characterized in that When the frequency selective surface structure includes two metal layers, the phase shifter and the feeding network are integrated on both metal layers; the part of the feeding network of the frequency selective surface that constitutes the feeding network of the first antenna is integrated on any one of the two metal layers, and the part of the feeding network of the frequency selective surface that constitutes the feeding network of the third antenna is integrated on the other of the two metal layers.

23. The antenna system according to any one of claims 16 to 22, characterized in that: The antenna system is formed on a printed circuit board; the printed circuit board includes a metal structure and a dielectric structure, at least a portion of the metal structure constitutes the floor, a plurality of radiators of each of the plurality of antennas, and the metal layer of the frequency selective surface structure; when the frequency selective surface structure also includes a dielectric layer, at least a portion of the dielectric structure of the printed circuit board constitutes the dielectric layer of the frequency selective surface structure.

24. A base station, characterized in that: The base station comprises the antenna system according to any one of claims 16 to 23 and a radio frequency module connected to the antenna system.

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