Filter structure, antenna system, and electronic device

Abstract

Embodiments of the present application provide a filter structure, an antenna system, and an electronic device, which are used for implementing differentiated processing on signals on different planes within a three-dimensional space. The filter structure provided in the embodiments of the present application comprises at least two magnetic resonance structures, at least two metal boundary structures, and an electrical resonance structure. Each magnetic resonance structure comprises a conductor region on a first plane, and the conductor region comprises an opening. The at least two magnetic resonance structures are periodically arranged in a direction perpendicular to the first plane. Each metal boundary structure comprises a metal sheet or a metal strip extending in a first direction. The at least two metal boundary structures are periodically arranged in a direction perpendicular to a plane on which the metal boundary structures are located, and the first direction is not parallel to the first plane. The electrical resonance structure is located between the two metal boundary structures, and the electrical resonance structure has a projection component on the plane on which the metal boundary structures are located. The electrical resonance operating frequency bands of the metal boundary structures and the electrical resonance structure match the magnetic resonance operating frequency band of the magnetic resonance structures.

Description

A filter structure, antenna system and electronic device

[0001] This application claims priority to Chinese Patent Application No. CN202510229568.9, filed on February 27, 2025, entitled "A Filter Structure, Antenna System and Electronic Device", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of wireless technology, and more particularly to a filtering structure, antenna system, and electronic device. Background Technology

[0003] In the field of wireless communication, antennas are used to radiate electromagnetic waves. Antenna sidelobe suppression and prevention of interference to other systems are important issues that need to be addressed in antenna system design.

[0004] Currently, electromagnetic waves are typically selected and manipulated using three dimensions: frequency, polarization, and incident angle, to address the aforementioned problems. Angle-selective surfaces, as a typical electromagnetic selection device, allow electromagnetic waves to propagate at certain incident angles and reflect electromagnetic waves at other incident angles, thereby achieving the selection and manipulation of electromagnetic waves.

[0005] Because angle-selective surfaces exhibit high transmittance only for signals incident at specific angles, the directionality of signals passing through them is highly uniform, thus limiting the antenna's coverage. For example, in the design of antenna systems such as base stations, setting the range of incident angles allowed by the angle-selective surface within the horizontal plane can shield upward electromagnetic signals, thereby avoiding interference with other systems. However, since the signal is confined to the range of incident angles allowed by the angle-selective surface, it cannot cover areas outside this range within the horizontal plane. Therefore, there is an urgent need for a filtering structure that can balance electromagnetic selectivity with wide coverage. Summary of the Invention

[0006] This application provides a filtering structure, antenna system, and electronic device for differentiated processing of signals on different planes in three-dimensional space, achieving a balance between electromagnetic function selection and wide coverage.

[0007] In a first aspect, embodiments of this application provide a filtering structure. This filtering structure includes at least two magnetic resonant structures, at least two metal boundary structures, and an electric resonant structure. Each magnetic resonant structure includes a conductor region on a first plane, the conductor region including an opening, and the at least two magnetic resonant structures are periodically arranged along a direction perpendicular to the first plane. Each metal boundary structure includes a metal sheet or strip extending along a first direction, and the at least two metal boundary structures are periodically arranged along a plane perpendicular to the plane containing the metal boundary structures, the first direction being non-parallel to the first plane. The electric resonant structure is located between the two metal boundary structures, and the electric resonant structure has a projection component on the plane containing the metal boundary structures; the electric resonant structure is separated from the metal boundary structures by a dielectric. The electric resonant operating frequency band of the metal boundary structures and the electric resonant structure matches the magnetic resonant operating frequency band of the magnetic resonant structure.

[0008] In this embodiment, a current loop is constructed on the first plane through multiple conductor regions with different opening directions of the magnetic resonant structure, realizing local coupling of electromagnetic energy in the loop, thereby strengthening the local field (including magnetic and electric fields) on the first plane. By utilizing the magnetic response of the local field-strengthened region on the magnetic resonant structure and the electric wall response on the metal boundary structure, differentiated electromagnetic function selection on different planes is achieved.

[0009] This application's embodiments achieve differentiated electromagnetic function selection on different planes based on the differences in wave transmission on different planes. When electromagnetic energy penetrates a structure, ignoring the energy loss of the structure itself, good wave transmission means that a larger portion of the electromagnetic energy passes through the structure, while a smaller portion is reflected by the structure; conversely, poor wave transmission means that a smaller portion of the energy passes through the structure, while a larger portion is reflected by the structure.

[0010] As shown in Figure 4, when the wave vector k scans in the yoz plane (i.e., the plane where the metal boundary structure is located), combining Figures A and B, for transverse electric (TE) mode electromagnetic waves, the angle between k and the second direction (z direction) increases, and consequently, the magnetic flux of the signal magnetic field H through the magnetic resonant structure decreases. Since the wave transmission of the magnetic resonant structure is related to the projection of the signal magnetic field H onto the magnetic resonant structure, the magnetic resonant structure exhibits angle-selective characteristics for TE mode electromagnetic waves scanning in the yoz plane (the above description, combined with Figure 4, is the case where the first plane where the magnetic resonant structure is located is perpendicular to the plane where the metal boundary structure is located. In reality, as long as the first plane is not parallel to the plane where the metal boundary structure is located, the magnetic resonant structure has a projection component perpendicular to the plane where the metal boundary structure is located. The signal magnetic field of the TE mode electromagnetic wave in the yoz plane has magnetic flux within the magnetic resonant structure, and the angle-selective characteristics can be achieved based on the changes in H within the magnetic resonant structure). Combining Figures A and C, for transverse electric (TE) mode electromagnetic waves, the angle-selective characteristics can be achieved based on the changes in H within the magnetic resonant structure. As the angle between k and the second direction (z direction) increases, the projection component of the signal electric field E in the first direction (y direction, i.e., the extension direction of the metal boundary structure) decreases. Since the wave transmission of the metal boundary structure is related to the projection component of the signal electric field E in the extension direction of the metal boundary structure (i.e., the first direction), the metal boundary structure exhibits angle selectivity characteristics for TM mode electromagnetic waves scanning in the yoz plane.

[0011] When the wave vector k scans in the xoz plane (perpendicular to the plane containing the metal boundary structure), combining diagrams D and E, for TE mode electromagnetic waves, the angle between k and the second direction (z direction) increases, and the projection component of E in the first direction (y direction, i.e., the extension direction of the metal boundary structure) remains constant. Since the wave transmission of the metal boundary structure is related to the projection component of the signal electric field E in the extension direction of the metal boundary structure (i.e., the first direction), the metal boundary structure exhibits wide-angle scanning characteristics for TE mode electromagnetic waves scanning in the xoz plane. Combining diagrams D and F, for TM mode electromagnetic waves, the angle between k and the second direction (z direction) increases, and the magnetic flux H through the magnetic resonant structure remains constant. The wave transmission of the structure is related to the magnetic flux of the signal magnetic field H in the magnetic resonant structure. Therefore, the magnetic resonant structure exhibits wide-angle scanning characteristics (also known as electromagnetic transparency) for TM mode electromagnetic waves scanning in the xoz plane. (The above description, combined with Figure 4, is the case where the first plane of the magnetic resonant structure is perpendicular to the plane of the metal boundary structure, that is, the first plane is on the xoz plane. In fact, as long as the angle between the first plane and the plane of the metal boundary structure is close to 90°, the first plane is approximately parallel to the xoz plane. The magnetic flux of the signal magnetic field of the TM mode electromagnetic wave in the xoz plane in the magnetic resonant structure is approximately constant. The wide-angle scanning characteristics can be achieved based on the approximate constant H in the magnetic resonant structure.)

[0012] Therefore, when the wave vector k scans in the yoz plane (i.e., the plane containing the metal boundary structure), both TE and TM mode electromagnetic waves exhibit angle-selective characteristics. When the wave vector k scans in the xoz plane (perpendicular to the plane containing the metal boundary structure), both TE and TM mode electromagnetic waves exhibit wide-angle scanning characteristics.

[0013] Among them, Figures B and F are generated based on the different magnetic flux responses of the local field enhancement region in the magnetic resonant structure on different surfaces, while Figures C and E are generated based on the different electric wall responses of the metal boundary structure on different surfaces.

[0014] The above explanation uses the angle selection function on the plane containing the metal boundary structure in Figure 4 as an example to illustrate the principle. When a gradient phase / amplitude design is adopted for the magnetic resonant structure (e.g., the embodiments shown in Figures 24a to 27c), the phase / amplitude selection function on the plane containing the metal boundary structure can be realized. Combined with the wide-angle scanning function on the first plane, the electromagnetic function selection on the first plane and the plane containing the metal boundary structure is differentiated.

[0015] Therefore, by using a filter structure that includes a magnetic resonant structure and a metal boundary structure, differential modulation of electromagnetic wave signals is achieved on the plane containing the metal boundary structure and the first plane. This enables electromagnetic function selection of signals within the plane containing the metal boundary structure (see the AC diagram in Figure 4) and electromagnetic transparency of signals within the first plane (see the DF diagram in Figure 4), thus achieving a balance between electromagnetic function selection and wide coverage.

[0016] For electromagnetic wave signals on the first plane, the structural design of the magnetic resonant structure affects the transmission frequency band of the TM mode electromagnetic wave on the first plane, thus affecting the operating frequency band of the magnetic resonant. Similarly, the structural designs of the metal boundary structure and the electric resonant structure affect the transmission frequency band of the TE mode electromagnetic wave on the first plane, thus affecting the operating frequency band of the electric resonant. This device adjusts the electric resonant operating frequency band through the electric resonant structure, matching it with the magnetic resonant operating frequency band. This ensures that when k scans in the xoz plane, the wide-angle scanning characteristics of the TE and TM mode electromagnetic waves are achieved in the same frequency band; and when k scans in the yoz plane, the electromagnetic function selection characteristics of the TE and TM mode electromagnetic waves are achieved in the same frequency band. The differentiated selection of electric and magnetic resonance in these two planes occurs within the same transmission frequency band, ensuring the uniformity of the transmission frequency band for the signal in each polarization mode and in each plane.

[0017] The filtering structure provided in this application can be applied to antenna systems (i.e., wireless communication applications, such as 5G and 6G communication). Each structure within the filtering structure utilizes its own characteristics to perform corresponding electromagnetic function selection on the electromagnetic wave signals of the antenna system. For example, the magnetic resonant structure utilizes magnetic resonant characteristics to achieve differentiated electromagnetic function selection on different planes of the electromagnetic wave signals; the metal boundary structure and the electric resonant structure utilize electric resonant characteristics to achieve differentiated electromagnetic function selection on different planes of the electromagnetic wave signals. The terms "magnetic resonant operating frequency band," "magnetic resonant operating frequency band of the magnetic resonant structure," "electric resonant operating frequency band," and "electric resonant operating frequency band of the metal boundary structure and the electric resonant structure" appearing in this application all indicate the frequency range within which the corresponding structure exerts a predetermined effect on the electromagnetic wave signals (i.e., differentiated electromagnetic function selection on different planes). Since the filtering structure is applicable to antenna systems, the above frequency ranges (i.e., various operating frequency bands) are the operating frequency bands of the antenna system. The operating frequency band of an antenna system refers to the frequency range within which the antenna system can operate normally (e.g., radiate signals, receive signals). Examples include the 5G and 6G frequency bands. The above analysis is based on the fact that the first plane containing the magnetic resonant structure is perpendicular to the plane containing the metal boundary structure, and the extension direction of the metal boundary structure (the first direction) is perpendicular to the first plane. Even if there are deviations in the above positional relationships, i.e., the first plane and the plane containing the metal boundary structure are not perfectly perpendicular, and the first direction is not perfectly perpendicular to the first plane; as long as the first plane and the plane containing the metal boundary structure are not parallel, and the first direction is not parallel to the first plane, then since the magnetic resonant structure has a component perpendicular to the plane containing the metal boundary structure, and the first direction has a component perpendicular to the first plane, the above-mentioned effect on the signal can also be achieved based on these components, and therefore the above analysis is still valid. Therefore, as long as the first plane and the plane containing the metal boundary structure are not parallel, and the first direction is not parallel to the first plane, the above-mentioned devices provided in the embodiments of this application can all realize differentiated electromagnetic function selection of signals on different planes (mutually perpendicular) in three-dimensional space.

[0018] In one alternative implementation, the filter structure is applied to the antenna system, with both the electrical resonant operating frequency band and the magnetic resonant operating frequency band matching the operating frequency band of the antenna system.

[0019] In the embodiments of this application, both the electric resonant operating frequency band and the magnetic resonant operating frequency band are matched to the operating frequency band of the antenna system, which enables the selection of differentiated electromagnetic functions of the antenna system signal on different planes.

[0020] In this application embodiment, the operating frequency band of the antenna system refers to the frequency range in which the antenna system can function normally (e.g., radiate signals, receive signals). For example, the 5G and 6G frequency bands.

[0021] In one alternative implementation, the electric resonant structure includes one or more pairs of resonant metal arms, each pair of arms being perpendicular to and symmetrical about the central axis, which is parallel to a second direction. The second direction is the direction of the boundary line between the plane containing the metal boundary structure and the first plane, and is different from the first direction. Alternatively, the electric resonant structure includes a ring-shaped metal structure.

[0022] In this embodiment, the symmetrical metal arms in the electric resonant structure constitute the structure of a dipole antenna. Because the dipole antenna has a wide frequency range, even if the transmission frequency bands of the magnetic resonant structure and the metal boundary structure differ significantly, the operating frequency band of the electric resonant structure can be adjusted to match the operating frequency band of the magnetic resonant structure. This relaxes the requirements for the design frequency bands of the magnetic resonant structure and the metal boundary structure, improving their flexibility.

[0023] In one alternative implementation, the filter structure includes at least two first substrates and a second substrate. A metal boundary structure is located on the first substrate, which extends along a first direction, and the at least two first substrates are periodically arranged along a direction perpendicular to the plane containing the metal boundary structure. A second substrate is located between the two first substrates, and an electric resonant structure is located on the second substrate. The electric resonant structure and the metal boundary structure are separated by a filling medium between the first and second substrates.

[0024] In this embodiment, the metal boundary structure and the electric resonant structure are disposed on different substrates, making the relative positional relationship between the metal boundary structure and the electric resonant structure more flexible and allowing for more feasible solutions.

[0025] Optionally, the filling medium can be air, expanding foam, etc., and this application does not limit it.

[0026] In one alternative implementation, the second substrate extends along a third direction, which is not parallel to either the first or second direction. That is, the second substrate is not parallel to the first substrate.

[0027] In this embodiment, the second substrate extends along a third direction, so the second substrate may not be parallel to the first substrate. The included angle between the second substrate and the first substrate can be any angle other than 0° and 90°, making the structure more flexible.

[0028] In one alternative implementation, the second substrate is parallel to the first substrate.

[0029] In this embodiment, the second substrate is parallel to the first substrate, which can better enhance the signal strength on the metal boundary structure, thereby improving the transmission characteristics.

[0030] In one alternative implementation, the second substrate includes at least two electrically resonant structures.

[0031] In one alternative implementation, the filter structure includes at least two third substrates. The at least two third substrates are periodically arranged along a direction perpendicular to the plane containing the metal boundary structure, and the electric resonant structure and the metal boundary structure are located on different surfaces of the third substrates. The electric resonant structure and the metal boundary structure are separated by a dielectric material in the third substrates.

[0032] In this embodiment, the electric resonant structure and the metal boundary structure are disposed on the same substrate, which results in a simple structure and lower cost.

[0033] In one alternative implementation, the magnetic resonant structure includes at least two conductor regions with different opening directions. The direction of the line connecting the openings of the different conductor regions of the magnetic resonant structure is not perpendicular to a second direction, which is the direction of the boundary line between the metal boundary structure plane and the first plane.

[0034] In this embodiment, the signal transmission direction is the second direction. By making the opening in the conductor region not perpendicular to the second direction, the coupling degree of the device to signals transmitted in the second direction can be improved, thereby enhancing signal transmission performance.

[0035] In one alternative implementation, the magnetic resonant structure includes at least two conductor regions, including a conductor region whose opening direction is not perpendicular to the second direction.

[0036] In one alternative implementation, the filter structure includes a fourth substrate, the surface of which lies in a first plane, and the magnetic resonant structure includes a conductor region located on the surface of the fourth substrate.

[0037] In one alternative implementation, the second substrate further includes a first slot, and the fourth substrate is connected to the second substrate through the first slot.

[0038] In this embodiment, the second substrate and the fourth substrate are fixed by the first slot on the second substrate. The fixing method is simple and does not require additional parts for fixing, which can simplify the structure.

[0039] In one alternative implementation, the fourth substrate has two ends along the second direction, designated as a first end and a second end. The magnetic resonant structure includes a first conductor region and a second conductor region. A first gap is formed in the first conductor region, passing through the first end but not the second end, and the opening of the first conductor region faces the first end. A second gap is formed in the second conductor region, passing through the second end but not the first end, and the opening of the second conductor region faces the second end.

[0040] In this embodiment, a current loop is constructed in the conductor region adjacent to the first and second gaps, thereby enhancing the electromagnetic field energy density through local coupling within the non-conductor gaps. This strengthens the magnetic response of the locally enhanced region on the magnetic resonant structure. Since the locally enhanced region on the magnetic resonant structure exhibits different magnetic response characteristics on different planes (reflecting electromagnetic transparency on the first plane and electromagnetic function selectivity on the plane containing the metal boundary structure), the enhanced magnetic response improves the differentiated selection effect of signals on different planes. Furthermore, since the first and second gaps pass through the first and second ends respectively (the second direction being the direction from the first end to the second end), high coupling of signals transmitted in the second direction can be achieved, improving signal transmission performance.

[0041] In one alternative implementation, the extension directions of the first and second gaps are parallel to the second direction.

[0042] In this embodiment, the first gap and the second gap extend parallel to the second direction, which can achieve high coupling of the magnetic resonant structure to the signal transmitted in the second direction and improve the signal transmission performance.

[0043] It is worth noting that the extension directions of the first and second gaps can also be close to the second direction. An extension direction close to the signal transmission direction (the second direction) still maintains a high degree of coupling to the signal, thereby improving signal transmission performance.

[0044] In one optional implementation, the first gap and the second gap are collinear along the second direction; or, the first gap and the second gap are not collinear along the second direction, and the projections of the first gap and the second gap along the fourth direction include overlapping portions, wherein the fourth direction is a direction perpendicular to the second direction on the fourth substrate; or, the first gap and the second gap are not collinear along the second direction, and at least one gap other than the first gap and the second gap are also included between the first end and the second end, wherein the projections of two adjacent gaps along the fourth direction include overlapping portions.

[0045] In this embodiment, if multiple gaps are not collinear along the second direction, the projection portions of adjacent gaps along the fourth direction are made to overlap. The signal coupling between the adjacent conductor regions and the adjacent gaps can be strengthened by the overlapping projection regions, thereby improving the signal coupling of the magnetic resonant structure and enhancing the signal transmission performance.

[0046] It is worth noting that multiple slits can also be collinear along a direction close to the second direction; or they can be non-collinear along a direction close to the second direction, and the projections of adjacent slits along the fourth direction include overlapping portions; the magnetic resonant structure of this design also has a high signal coupling degree, which is not limited in this application.

[0047] In one alternative implementation, the magnetic resonant structure includes at least two conductor regions, comprising at least two conductor rings on a fourth substrate, each conductor ring including an opening. The at least two conductor rings include at least two conductor rings with opening orientations different from each other.

[0048] In this embodiment, a current loop is constructed using open conductor rings. Since multiple conductor rings have different opening directions, reverse currents can be generated on adjacent conductor rings, thereby achieving localized field reinforcement in the gaps between adjacent conductor rings. This allows for the utilization of the different magnetic response characteristics exhibited by the localized field reinforcement region on different planes (reflecting the electromagnetic transparency characteristics on the first plane and the electromagnetic function selection characteristics on the plane containing the metal boundary structure), enabling differentiated signal selection on different planes.

[0049] In the embodiments of this application, the direction in which the geometric center of the conductor ring points to the opening of the conductor ring is called the opening direction of the conductor ring. For example, in Figure 19b, the opening direction of conductor ring A is upward, and the opening direction of conductor ring B is downward.

[0050] In one alternative implementation, at least two conductor rings include a first conductor ring and a second conductor ring with opposite opening directions.

[0051] In this embodiment, the opening directions of the conductor rings are reversed, which can increase the coupling degree of the signals by the multiple conductor rings, thereby improving the signal transmission characteristics.

[0052] It is worth noting that the opening directions of the first conductor ring and the second conductor ring can also be approximately opposite, and multiple conductor rings can also have a high degree of coupling to the signal. This application does not limit this.

[0053] In one alternative implementation, at least two conductor rings include a conductor ring facing a first end and a conductor ring facing a second end. The first end and the second end are the two ends of the fourth substrate along a second direction.

[0054] In this embodiment, the opening direction of the conductor ring is consistent with the signal transmission direction (second direction), which can improve the coupling degree of multiple conductor rings to the signal transmitted in the second direction, thereby improving the signal transmission characteristics.

[0055] It is worth noting that the multiple conductor rings may also include a conductor ring approximately facing the first end and a conductor ring approximately facing the second end. Such multiple conductor rings will also have a high degree of coupling to the signal, and this application does not limit this.

[0056] In one alternative implementation, the fourth substrate includes at least two magnetic resonant structures distributed along a fourth direction, which is a direction on the fourth substrate perpendicular to the second direction. The at least two magnetic resonant structures in the fourth direction include at least two magnetic resonant structures with opening connection directions different from each other. The opening connection direction is the direction in which the openings of at least two conductor rings in the magnetic resonant structures are connected.

[0057] In the embodiments of this application, different magnetic resonant structures distributed along the fourth direction have different opening connection directions, which can achieve phase modulation of different regions in the fourth direction.

[0058] The main lobe and higher sidelobes are generated because the signal of the oscillator interferes and expands at the main lobe / higher sidelobes. Through the above structural design, on the one hand, the phase distribution of the oscillator signal can be adjusted to eliminate signal interference at the higher sidelobes and suppress them; on the other hand, through phase synthesis modulation, the spatial position where energy interference is enhanced can be adjusted, thereby controlling / changing the direction of the beam main lobe.

[0059] In the embodiments of this application, the direction through the openings of the multiple conductor rings is called the opening connection direction of the magnetic resonance structure. For example, in Figure 19b, the opening direction of conductor ring A is upward and the opening direction of conductor ring B is downward. The opening connection direction of the magnetic resonance structure is the up-down direction (through the openings of conductor ring A and conductor ring B).

[0060] In one alternative implementation, at least two conductor rings are nested inside and outside the other.

[0061] In the embodiments of this application, the inner and outer nested conductor ring structure can improve the structural compactness and reduce the device size.

[0062] In one alternative implementation, the fourth substrate further includes a second slot, through which the first substrate or the third substrate is connected to the fourth substrate.

[0063] In this embodiment, the fourth substrate is fixed to the first or third substrate by the second slot on the fourth substrate. The fixing method is simple, does not require additional parts for fixing, and can simplify the structure.

[0064] In one alternative implementation, the metal boundary structure is perpendicular to the first plane.

[0065] In this embodiment, if the metal boundary structure is perpendicular to the first plane, the two surfaces with different magnetic response characteristics generated by the magnetic resonant structure (the first plane and the plane containing the metal boundary structure, i.e., the differential selection plane of magnetic resonance) are completely matched with the two surfaces with different electrical response characteristics of the metal boundary structure and the electric resonant structure (the plane containing the metal boundary structure and the plane perpendicular to the plane containing the metal boundary structure, i.e., the differential selection plane of electric resonance). This achieves the unification of the differential selection planes of magnetic and electric resonance, realizing high uniformity in signal differential selection across different polarization modes and different planes.

[0066] It is worth noting that the metal boundary structure can also be approximately perpendicular to the first plane, which can achieve a high degree of uniformity in signal differentiation selection in different polarization modes and different planes. This application does not limit this.

[0067] In one alternative implementation, the metal boundary structure includes at least two metal strips arranged along a second direction, the at least two metal strips extending along a first direction, the second direction being the direction of the boundary line between the plane containing the metal boundary structure and the first plane.

[0068] In this embodiment, multiple metal strips are used to achieve an equivalent electric wall response of a complete metal surface, thereby enabling differentiated electromagnetic function selection for signals on different planes. The metal strips effectively control the electromagnetic field distribution on the metal boundary structure, enhancing the signal strength and thus improving transmission characteristics.

[0069] Furthermore, the metal strips on the metal boundary structure can also work in conjunction with the electric resonant structure to adjust the electric resonant operating frequency band so that the electric resonant operating frequency band is consistent with the magnetic resonant operating frequency band.

[0070] In one alternative design, the first / third substrate, comprising multiple metal strips, is a printed circuit board (PCB). Compared to a solid metal surface, the first / third substrate composed of a PCB is lighter, which can reduce the weight of the device.

[0071] In one alternative implementation, the first substrate includes a metal shell and a hollow cavity extending along a first direction.

[0072] In this embodiment of the application, signal lines and other devices can be embedded in the hollow cavity of the first substrate, and electromagnetic shielding of the internal devices can be achieved through the metal shell of the first substrate.

[0073] In one alternative implementation, the electric resonant operating frequency band is matched with the magnetic resonant operating frequency band, including: the overlap range between the electric resonant operating frequency band and the magnetic resonant operating frequency band is greater than or equal to a first threshold, and the first threshold is greater than or equal to 50%.

[0074] Optionally, the first threshold can be 50%, 60%, 70%, 80%, 90%, etc., and this application does not limit it.

[0075] In this embodiment, the electric resonant operating frequency band is adjusted by the electric resonant structure to achieve matching between the electric resonant operating frequency band and the magnetic resonant operating frequency band. This ensures that when an electromagnetic signal is incident on the filter structure, the impedance matching condition between the electromagnetic signal transmitter and the filter structure is met within a specific frequency range (e.g., 5G, 6G communication frequency bands), allowing most of the electromagnetic signal's energy to pass through the filter structure.

[0076] In the embodiments of this application, when impedance matching is achieved, the transmittance of the filter structure to electromagnetic signals within the frequency band is greater than the second threshold. The second threshold can be 80%, 90%, etc., and this application does not limit it.

[0077] Secondly, embodiments of this application provide an antenna system. The antenna system includes an antenna element and a filtering structure, wherein the filtering structure is the filtering structure described in the first aspect or its implementation. In the filtering structure, the direction of the boundary line between the metallic boundary structure and the first plane is a second direction, and the antenna element is located in the second direction of the filtering structure.

[0078] In one alternative implementation, the antenna system also includes a support for fixing the antenna elements and the filtering structure.

[0079] Thirdly, embodiments of this application provide an electronic device. This electronic device includes an antenna system, which is the antenna system described in the second aspect or its implementation.

[0080] In one alternative implementation, the electronic devices are base stations, remote radio units (RRUs) of base stations, routers, etc., which can radiate electromagnetic energy.

[0081] The beneficial effects of the second and third aspects are described in the first aspect and will not be repeated here. Attached Figure Description

[0082] Figure 1a is a schematic diagram of antenna signal interference between different systems provided in this application;

[0083] Figure 1b is a schematic diagram of an antenna system provided in an embodiment of this application;

[0084] Figure 2 is a schematic diagram of a filtering structure provided in an embodiment of this application;

[0085] Figure 3a is a schematic diagram of a magnetic resonant structure provided in an embodiment of this application;

[0086] Figure 3b is a schematic diagram of magnetic field enhancement on a magnetic resonant structure provided in an embodiment of this application;

[0087] Figure 4 is a schematic diagram of the selection of electromagnetic functions of the filtering structure provided in the embodiment of this application for signals in different planes;

[0088] Figure 5 is a schematic diagram of signal frequency shift in the xoz plane provided in an embodiment of this application;

[0089] Figure 6 is a schematic diagram of a signal frequency shift to outside the transmission frequency band within a specific angle range provided in an embodiment of this application;

[0090] Figure 7a is a schematic diagram of the transmission amplitude characteristic curve in the TE polarization mode in the xoz plane provided by an embodiment of this application;

[0091] Figure 7b is a schematic diagram of the transmission amplitude characteristic curve in the TM polarization mode in the xoz plane provided by an embodiment of this application;

[0092] Figure 7c is a schematic diagram of the transmission amplitude characteristic curve in the TE polarization mode in the yoz plane provided in the embodiment of this application;

[0093] Figure 8 is a schematic diagram of a transmission amplitude curve under different incident angles provided in the embodiments of this application;

[0094] Figure 9a is a schematic diagram of the metal boundary structure and the electric resonant structure provided in the embodiments of this application located on different substrates;

[0095] Figure 9b is a schematic diagram of the metal boundary structure and the electric resonant structure provided in the embodiment of this application, which are located on the same substrate.

[0096] Figure 10a is a schematic diagram of a structure of a second substrate / third substrate provided in an embodiment of this application;

[0097] Figure 10b is a schematic diagram of an electric resonant structure provided in an embodiment of this application;

[0098] Figure 11a is a schematic diagram of the transmission amplitude characteristic curves of the TM mode under different dipole spacings provided in the embodiments of this application;

[0099] Figure 11b is a schematic diagram of the transmission amplitude characteristic curves of the TE mode under different dipole spacings provided in the embodiments of this application;

[0100] Figure 12a is a top view of the filter structure provided in the embodiment of this application along the z-axis.

[0101] Figure 12b is a top view of the filter structure provided in the embodiment of this application along the z-axis.

[0102] Figure 13a is another schematic diagram of the filtering structure provided in an embodiment of this application;

[0103] Figure 13b is a schematic diagram of a fourth substrate of the filter structure provided in an embodiment of this application;

[0104] Figure 14a is a schematic diagram of a second / third substrate of the filtering structure provided in an embodiment of this application;

[0105] Figure 14b is another structural schematic diagram of the second / third substrate of the filtering structure provided in the embodiment of this application;

[0106] Figure 14c is another structural schematic diagram of the second / third substrate of the filtering structure provided in the embodiment of this application;

[0107] Figure 15a is a schematic diagram of the filter structure provided in this application combined with an antenna array;

[0108] Figure 15b is a schematic diagram of the filtering structure provided in the embodiment of this application for suppressing interference to inter-system communication;

[0109] Figure 15c is a schematic diagram of the arrangement of vibrators on the antenna array provided in an embodiment of this application;

[0110] Figure 16a is a schematic diagram of the filtering structure provided in an embodiment of this application for suppressing sidelobes;

[0111] Figure 16b shows the radiation pattern of the filter structure provided in the embodiment of this application before and after suppressing sidelobes;

[0112] Figure 17 is a schematic diagram of a magnetic resonant structure including a non-conductor gap provided in an embodiment of this application;

[0113] Figure 18a is a schematic diagram of a fourth substrate including a hollow cavity provided in an embodiment of this application;

[0114] Figure 18b is a schematic diagram of a fourth substrate including multiple metal strips provided in an embodiment of this application;

[0115] Figure 19a is a schematic diagram of a magnetic resonant structure including a conductor ring provided in an embodiment of this application;

[0116] Figure 19b is a schematic diagram of the magnetic field enhancement on the magnetic resonant structure shown in Figure 19a;

[0117] Figure 20 is another structural schematic diagram of a magnetic resonant structure including a conductor ring provided in an embodiment of this application;

[0118] Figure 21 is a schematic diagram of the transmission amplitude characteristic curves under different incident angles provided in the embodiments of this application;

[0119] Figure 22 is another structural schematic diagram of a magnetic resonant structure including a conductor ring provided in an embodiment of this application;

[0120] Figure 23 is a schematic diagram of the opening direction of the conductor ring provided in an embodiment of this application;

[0121] Figure 24a is a schematic diagram of a fourth substrate with different opening directions of the conductor ring provided in an embodiment of this application;

[0122] Figure 24b is a schematic diagram of a fourth substrate with different sizes of conductor rings provided in an embodiment of this application;

[0123] Figure 24c is a schematic diagram of a fourth substrate with different opening sizes of conductor rings provided in an embodiment of this application;

[0124] Figure 25 is a schematic diagram of the transmission amplitude and transmission phase at different rotation angles provided in the embodiments of this application;

[0125] Figure 26 is a schematic diagram of the transmission amplitude characteristic curves of different opening sizes of the opening ring provided in the embodiments of this application;

[0126] Figure 27a is a schematic diagram of a fourth substrate with different thicknesses of non-conductor gaps provided in an embodiment of this application;

[0127] Figure 27b is a schematic diagram of a fourth substrate with different lengths of non-conductive gaps provided in an embodiment of this application;

[0128] Figure 27c is a schematic diagram of a fourth substrate with different spacing of non-conductor gaps provided in an embodiment of this application. Detailed Implementation

[0129] The embodiments of this application will now be described with reference to the accompanying drawings. Those skilled in the art will recognize that, with technological advancements and the emergence of new scenarios, the technical solutions provided in the embodiments of this application are equally applicable to similar technical problems.

[0130] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms are interchangeable where appropriate; this is merely a way of distinguishing objects with the same attributes in the embodiments of this application. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, so that a process, method, system, product, or apparatus that comprises a series of units is not necessarily limited to those units, but may include other units not explicitly listed or inherent to those processes, methods, products, or apparatuses. Additionally, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, at least one of a, b, or c can be expressed as: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0131] Antennas / antenna arrays have the ability to radiate electromagnetic waves. If the intensity of radiation from an antenna / antenna array in each direction is represented by a vector originating from the origin, then the surface formed by connecting all the endpoints of the vectors is the antenna's radiation pattern.

[0132] A radiation pattern is also called a lobe pattern. In a radiation pattern, the radiation lobe that contains the direction of maximum desired radiation is called the main lobe of the antenna, also known as the antenna beam. Lobes other than the main lobe are called side lobes or lateral lobes.

[0133] With the development of communication technology, base station antennas are expanding to higher frequency bands and millimeter wave bands. However, current high-frequency base station communication suffers from interference with fixed services of other systems (i.e., communication systems outside the current communication system) at higher altitudes.

[0134] For example, as shown in Figure 1a, the beam of the antenna array includes different directions such as horizontal, upward, and downward. For a different system located at a high position (i.e., a communication system outside this antenna array), the communication of the different system will be interfered with by the upward beam of the antenna array.

[0135] Currently, angle-selective surfaces are commonly used to suppress signals incident at oblique angles. These surfaces incorporate resonant elements; by adjusting the size of these elements, impedance matching is achieved when the electromagnetic signal is incident perpendicularly to them, thus acting as a bandpass. Conversely, they act as a bandstop for electromagnetic signals incident at oblique angles. This effectively filters electromagnetic signals at different incident angles, removing interference signals.

[0136] Because the angle-selective surface only transmits signals incident at a specific angle, the directionality of the signal is highly consistent after passing through the angle-selective surface, which limits the coverage range of the antenna.

[0137] For example, in Figure 1a, setting the range of incident angles allowed by the angle-selective surface to the right horizontally can shield upward-sloping electromagnetic signals, thus avoiding interference with other systems. However, since the angle-selective surface only allows signals to the right horizontally, signals in the left, forward, and backward directions within the horizontal plane cannot pass through the angle-selective surface, resulting in limited signal coverage within the horizontal plane.

[0138] Therefore, there is an urgent need for a filter structure that can balance electromagnetic function selection and wide coverage.

[0139] To improve coverage while achieving electromagnetic function selection, embodiments of this application provide a three-dimensional filtering structure (also known as an electromagnetic function selection device), an antenna system, and an electronic device. The filtering structure provided in this application achieves electromagnetic function selection for signals within a certain plane and electromagnetic transparency for signals in another plane perpendicular to that plane by differentially modulating electromagnetic signals in different planes (mutually perpendicular planes) in three-dimensional space. This achieves a balance between electromagnetic function selection and wide coverage.

[0140] The filtering structure provided in this embodiment can be applied to the antenna system shown in Figure 1b. As shown in Figure 1b, the antenna system includes an antenna element and a filtering structure. The antenna element can be an antenna or an antenna array. The filtering structure is located in the main lobe direction of the antenna element.

[0141] As shown in Figure 2, the filter structure 2000 (also called an electromagnetic function selection device) provided in this embodiment includes at least two magnetic resonant structures 2100, at least two metal boundary structures 2200, and an electric resonant structure 2300. The filter structure 2000 can be the filter structure shown in Figure 1b.

[0142] The magnetic resonant structure 2100 includes a conductor region on a first plane, and the conductor region includes an opening. At least two magnetic resonant structures 2100 are periodically arranged along a direction perpendicular to the first plane.

[0143] The metal boundary structure 2200 includes a metal sheet or strip extending along a first direction, which is not parallel to a first plane. At least two metal boundary structures 2200 are arranged periodically along a plane perpendicular to the plane containing the metal boundary structures.

[0144] The electric resonant structure 2300 is located between two metal boundary structures 2200. The electric resonant structure 2300 has a projection component on the plane containing the metal boundary structures 2200. For example, in the structure shown in Figure 2, the plane containing the electric resonant structure 2300 is parallel to the plane containing the metal boundary structures 2200. The electric resonant structure 2300 and the metal boundary structures 2200 are separated by a medium, which can be a solid medium or air, etc., and this application does not limit this.

[0145] Preferably, the extension direction (first direction) of the metal boundary structure 2200 is perpendicular to the plane (first plane) where the magnetic resonant structure 2100 is located (e.g., the y-axis direction shown in Figure 2). Optionally, the first direction may also deviate from the y-axis direction in Figure 2, as long as the first direction is not parallel to the first plane.

[0146] Preferably, the metal boundary structure 2200 is perpendicular to the first plane containing the magnetic resonant structure 2100 (for example, the metal boundary structure 2200 in Figure 2 is on the yoz plane). Optionally, the metal boundary structure 2200 may also be offset from the yoz plane in Figure 2, as long as the metal boundary structure 2200 is not parallel to the first plane.

[0147] In the structure shown in Figure 2, the conductor region of the magnetic resonant structure 2100 is used to transmit current, and therefore a magnetic field is present around the conductor region. The conductor region has an opening, thus forming a loop structure. By limiting the spatial range of the electromagnetic field through the loop structure of the conductor region, the energy density of the electromagnetic field is locally coupled and enhanced near the opening of the conductor region, thereby achieving magnetic resonance through the magnetic resonant structure 2100.

[0148] In this embodiment, the filter structure 2000 may include a fourth substrate. The surface of the fourth substrate is located on a first plane, and the magnetic resonant structure 2100 includes a conductor region located on the surface of the fourth substrate. In this embodiment, the direction of the boundary line between the plane where the metal boundary structure 2200 is located (the yoz plane in FIG. 2) and the first plane (the plane where the magnetic resonant structure 2100 is located, the xoz plane in FIG. 2) is called the second direction (the z-axis direction in FIG. 2). FIG. 3a is a schematic diagram of a structure of the fourth substrate, with the two ends of the fourth substrate along the second direction being the first end and the second end, respectively. The magnetic resonant structure 2100 couples electromagnetic energy by constructing a current loop, so that electromagnetic energy is transferred from the first end to the second end of the fourth substrate.

[0149] As shown in Figure 3a, in one example, the magnetic resonant structure 2100 includes a first conductor region 2111 and a second conductor region 2112. A first gap is formed in the first conductor region 2111, passing through a first end of the fourth substrate but not through a second end, such that the opening of the first conductor region 2111 faces the first end. A second gap is formed in the second conductor region 2112, passing through a second end of the fourth substrate but not through a first end, such that the opening of the second conductor region 2112 faces the second end.

[0150] Optionally, the surface of the fourth substrate may include a conductor layer. Then, the first conductor region 2111 is the conductor region on the conductor layer that is adjacent to the first gap, and the second conductor region 2112 is the conductor region on the conductor layer that is adjacent to the second gap.

[0151] In this embodiment, the magnetic resonant structure 2100 couples electromagnetic energy through a current loop, so that electromagnetic energy is transferred from the first end to the second end.

[0152] The principle of electromagnetic energy coupling in the magnetic resonant structure 2100 is as follows: the conductor region of the magnetic resonant structure 2100 is used to transmit current, and therefore a magnetic field is present around the conductor region. The spatial range of the electromagnetic field is limited by the loop structure of the conductor region, so that the electromagnetic field energy density is locally coupled and enhanced in the non-conductor gap.

[0153] As shown in Figure 3b, the conductor regions adjacent to the first gap, the third gap, and the second gap form a current loop. The current flows from the first end through the first conductor region 2111 adjacent to the first gap, the conductor region adjacent to the third gap, and the second conductor region 2112 adjacent to the second gap, to the second end.

[0154] Taking the second conductor region 2112 as an example, the currents on both sides of the second gap in the second conductor region 2112 are in opposite directions. According to the right-hand screw law, the magnetic fields generated by the currents in the second conductor region 2112 are in the same direction at the second gap. Therefore, the magnetic fields are superimposed on the second gap, strengthening the magnetic field, thereby achieving magnetic resonance through the magnetic resonance structure 2100.

[0155] As shown in Figure 3a, the fourth substrate may further include multiple second slots. The second slots are used to mount the first metal boundary structure 2200.

[0156] In the structure shown in Figure 2, at least two parallel metallic boundary structures 2200 can achieve standing waves in the electric field. The electric resonant structure 2300 is an antenna structure design or an antenna-like structure design, which can adjust the standing wave frequency band, thereby achieving electric resonance through the at least two metallic boundary structures 2200 and the electric resonant structure 2300.

[0157] The electric resonant structure 2300 can adjust the standing wave frequency band of the metal boundary structure 2200, thereby adjusting the electric resonant operating frequency band. Therefore, in this embodiment, the electric resonant structure 2300 adjusts the electric resonant operating frequency band of the metal boundary structure 2200 and the electric resonant structure 2300, so that the electric resonant operating frequency band matches the magnetic resonant operating frequency band of the magnetic resonant structure 2100.

[0158] This embodiment of the application, through the structure shown in Figure 2, achieves electromagnetic transparency of signals within the first plane (i.e., the plane where the magnetic resonant structure 2100 is located) and electromagnetic function selection of signals within the plane where the metal boundary structure 2200 is located, thereby realizing differentiated modulation of electromagnetic wave signals in different planes (mutually perpendicular planes) in three-dimensional space. The principle is that the filter structure 2000 achieves electromagnetic transparency of signals within the first plane (i.e., the plane where the magnetic resonant structure 2100 is located) and electromagnetic function selection of signals within the plane where the metal boundary structure 2200 is located.

[0159] 1. The filter structure 2000 enables the selection of the angle of the signal in the plane where the metal boundary structure 2200 is located.

[0160] By utilizing the local field of the magnetic resonant structure 2100 to enhance the magnetic response of the region, the magnetic resonant structure 2100 can exhibit different characteristics in different directions within the plane (yoz plane) where the metal boundary structure 2200 is located, thus achieving angle selection on the yoz plane.

[0161] As shown in Figures A and B of Figure 4, when the signal is in TE polarization mode, as the signal transmission direction k scans on the plane (yoz plane) containing the metal boundary structure 2200, the magnetic field direction H of the signal changes with the direction of k, causing a change in the size of the projection of H onto the first plane (xoz plane). Therefore, the magnetic flux within the non-conductor gaps (magnetic field reinforcement regions, such as the first and second gaps shown in Figure 3) of the magnetic resonant structure 2100 (within the xoz plane) changes with the scanning of the transmission direction k. When k is in the z-axis direction (the second direction), H is perpendicular to the first plane (xoz plane), and the magnetic flux in the magnetic field reinforcement region within the magnetic resonant structure 2100 is at its maximum. The larger the angle between k and the z-axis (the second direction), the smaller the magnetic flux.

[0162] Assuming f0 is the frequency of the signal when k is in the z-axis direction (the second direction) (i.e., when the magnetic flux is at its maximum), the transmission frequency band of the magnetic resonant structure 2100 is set near f0. When the signal transmission direction k scans on the plane (yoz plane) where the metal boundary structure 2200 is located, the change in magnetic flux causes the signal to shift based on f0.

[0163] As shown in Figure 5, θ1 is the incident angle of the signal on the plane where the metal boundary structure 2200 is located, and θ is the angle between the signal transmission direction k and the z-axis direction (the second direction), corresponding to the signal frequency. Where k1 is a characteristic parameter of the magnetic resonant structure 2100, and is related to the magnetic flux response coefficient of the magnetic resonant structure 2100. It can be seen that on the plane containing the metal boundary structure 2200, the larger the angle θ1 between the signal transmission direction k and the z-axis direction (the second direction), the larger f1 becomes. When the incident angle θ1 on the plane containing the metal boundary structure 2200 is greater than a certain value (for example, the range of θ1 corresponding to the transmission frequency band is -30° to 30°), f1 falls outside the transmission frequency band and is thus cut off. This means that on the plane containing the metal boundary structure 2200 (yoz plane), when the angle between the signal transmission direction k and the z-axis is -30° ≤ θ1 ≤ 30°, the signal is on; when θ1 > 30° or θ1 < -30°, the signal is off.

[0164] Therefore, the TE mode signal in the plane where the metal boundary structure 2200 is located exhibits angle-selective characteristics, and the magnetic flux response characteristics of the magnetic resonant structure 2100 to the TE signal in the plane where the metal boundary structure 2200 is located are angle-selective.

[0165] By utilizing the electric wall response of the metal boundary structure 2200, the metal boundary structure 2200 can exhibit different characteristics in different directions within the plane (yoz plane) where the metal boundary structure 2200 is located, thereby achieving angle selection on the yoz plane.

[0166] As shown in Figures A and C of Figure 4, when the signal is in TM polarization mode, as the signal transmission direction k scans on the plane (yoz plane) containing the metal boundary structure 2200, the electric field direction E of the signal changes with the direction of k, causing a change in the magnitude of the component of E in the y-axis direction (i.e., the extension direction of the metal boundary structure 2200). Therefore, the electric field component in the extension direction of the metal boundary structure 2200 (the first direction, i.e., the y-axis direction) changes with the scanning of the transmission direction k. When k is in the z-axis direction, the component of E in the y-axis direction is the largest; the larger the angle between k and the z-axis direction (the second direction), the smaller the component of E in the y-axis direction (the first direction).

[0167] Assuming f0 is the frequency of the signal when k is in the z-axis direction (the second direction) (i.e., when the component of E in the y-axis direction is maximum), the transmission frequency band of the metal boundary structure 2200 is set near f0. Similar to the angle selection of the magnetic resonant structure 2100, when the signal transmission direction k scans on the plane (yoz plane) where the metal boundary structure 2200 is located, the magnitude of the component of E in the y-axis changes, causing the signal to shift based on f0.

[0168] As shown in Figure 6, θ2 is the incident angle on the plane where the signal metal boundary structure 2200 is located, and is the angle between the signal transmission direction k and the z-axis direction (second direction), corresponding to the signal frequency. Where k2 is a characteristic parameter of the metal boundary structure 2200, and is related to the electrical response coefficient of the metal boundary structure 2200. It can be seen that on the plane containing the metal boundary structure 2200, the larger the angle θ2 between the signal transmission direction k and the z-axis direction (the second direction), the larger f2 becomes. When the incident angle θ2 on the plane containing the metal boundary structure 2200 is greater than a certain value (for example, the range of θ2 corresponding to the transmission frequency band is -30° to 30°), f2 falls outside the transmission frequency band and is thus cut off. Therefore, on the plane containing the metal boundary structure 2200 (yoz plane), when the angle between the signal transmission direction k and the z-axis is -30° ≤ θ2 ≤ 30°, the signal is on; when θ2 > 30° or θ2 < -30°, the signal is off.

[0169] Therefore, the TM mode signal in the plane where the metal boundary structure 2200 is located exhibits angle-selective characteristics, and the magnetic flux response characteristics of the metal boundary structure 2200 to the TM signal in the plane where the metal boundary structure 2200 is located are angle-selective.

[0170] In summary, by enhancing the magnetic response of the local field region of the magnetic resonant structure 2100, angle selection of TE mode signals within the plane containing the metal boundary structure 2200 is achieved; by utilizing the electric wall response of the metal boundary structure 2200, angle selection of TM mode signals within the plane containing the metal boundary structure 2200 is achieved. Therefore, the filter structure 2000 can achieve angle selection for signals of different polarization modes within the plane containing the metal boundary structure 2200.

[0171] It is worth noting that the filter structure 2000 provided in this application does not limit the electromagnetic function selection type of the signal on the plane where the metal boundary structure 2200 is located. In addition to angle selection, phase selection, amplitude selection, etc. of signals with different polarization modes in the first plane can also be achieved through special design of the magnetic resonant structure 2100, as shown in the embodiments shown in Figures 24a to 27c below.

[0172] 2. The filter structure 2000 enables wide-angle scanning of signals within the first plane (the plane where the magnetic resonant structure 2100 is located).

[0173] By utilizing the local field enhancement region of the magnetic resonant structure 2100, the magnetic resonant structure 2100 can exhibit the same characteristics in different directions within the first plane (xoz plane, i.e. the plane where the magnetic resonant structure 2100 is located), thus realizing wide-angle scanning on the xoz plane.

[0174] As shown in Figures D and F of Figure 4, when the signal is in TM polarization mode, the magnetic field direction H of the signal is always perpendicular to the first plane (xoz plane) when the signal transmission direction k scans on the first plane (xoz plane). The magnetic flux in the non-conductor gaps (magnetic field reinforcement regions, such as the first gap and second gap shown in Figure 3) of the magnetic resonant structure 2100 (within the xoz plane) is constant and maximum with the scanning of the transmission direction k, and signals in all transmission directions on the first plane can be transmitted.

[0175] Therefore, the TM mode signal in the first plane exhibits wide-angle scanning characteristics, and the magnetic flux response characteristics of the magnetic resonant structure 2100 to the TM signal in the first plane are electromagnetically transparent.

[0176] By utilizing the electric wall response of the metal boundary structure 2200, the metal boundary structure 2200 can exhibit the same characteristics in different directions within the first plane (xoz plane), thereby achieving wide-angle scanning on the xoz plane.

[0177] As shown in Figures D and E of Figure 4, when the signal is in TE polarization mode, the electric field direction E of the signal is always parallel to the y-axis direction (i.e., the extension direction of the metal boundary structure 2200) as the signal transmission direction k scans on the first plane (xoz plane). The electric field component E on the extension direction (first direction) of the metal boundary structure 2200 is constant and maximum with the scanning of the transmission direction k, and signals in all transmission directions on the first plane can be transmitted.

[0178] Therefore, the TE mode signal in the first plane exhibits wide-angle scanning characteristics, and the electrical response (electric wall response) characteristics of the metal boundary structure 2200 to the TE signal in the first plane are electromagnetically transparent.

[0179] In summary, wide-angle scanning of TM mode signals in the first plane is achieved by enhancing the magnetic response of the local field of the magnetic resonant structure 2100; and wide-angle scanning of TE mode signals in the first plane is achieved by utilizing the electric wall response of the metallic boundary structure 2200. Therefore, the filter structure 2000 can achieve wide-angle scanning of signals with different polarization modes in the first plane.

[0180] 3. The electric resonant mechanism 2300 achieves the matching of the operating frequency band of the magnetic resonant structure 2100 and the metal boundary structure 2200.

[0181] In this embodiment of the application, by adjusting the shape, size and other parameters of the inner conductor region of the magnetic resonant structure 2100, the passband (transmission band) of the TE mode signal in the plane where the metal boundary structure 2200 shown in Figure B of Figure 4 is located, and the passband of the TM mode signal in the first plane shown in Figure F of Figure 4, can be adjusted so that the passbands of Figure B and Figure F are matched.

[0182] By adjusting the extension length of the metal boundary structure 2200 (in the first direction, the y-axis direction), its width (in the second direction, the z-axis direction), and the spacing between multiple metal boundary structures 2200, the resonant frequencies of different signal directions on the metal boundary structure 2200 in the plane where the metal boundary structure 2200 is located are adjusted, thereby affecting the signal passband of the TM mode in the plane where the metal boundary structure 2200 is located as shown in Figure C, so that the passband of Figure C matches that of Figures B and F.

[0183] For the TE mode signal in the first plane shown in Figure E in Figure 4, the electric field of the signal is parallel to the electric resonant structure 2300. The electric resonant structure 2300 can generate an electric response. The electric resonant structure 2300 and the metal boundary structure 2200 generate an electric resonance, thereby adjusting the signal passband of the TE mode in the first plane shown in Figure E through the electric resonant structure 2300, so that the passband of Figure E is matched with Figures C, B and F.

[0184] Based on the above three points regarding the differentiated electromagnetic function selection function of the filter structure 2000 in different planes, it can be seen that in this embodiment, by utilizing the different magnetic flux response characteristics of the local field reinforcement region of the magnetic resonant structure 2100 to the TE mode signal (Figure B in Figure 4) in the plane where the metal boundary structure 2200 is located and the TM mode signal (Figure F in Figure 4) in the first plane, electromagnetic function selection of the TE signal in the plane where the metal boundary structure 2200 is located and electromagnetic transparency of the TM signal in the first plane are achieved; by utilizing the different electrical response characteristics of the metal boundary structure 2200 to the TM mode signal (Figure C in Figure 4) in the plane where the metal boundary structure 2200 is located and the TE mode signal (Figure E in Figure 4), electromagnetic function selection of the TM signal in the plane where the metal boundary structure 2200 is located and electromagnetic transparency of the TE signal in the first plane are achieved. Electromagnetic wave signals can all be decomposed into TE mode components and TM mode components. Therefore, by using a filter structure 2000 comprising a magnetic resonant structure 2100 and a metal boundary structure 2200, differential modulation of electromagnetic wave signals is achieved on the plane containing the metal boundary structure 2200 and the first plane. This enables electromagnetic function selection of signals within the plane containing the metal boundary structure 2200 and electromagnetic transparency of signals within the first plane perpendicular to the plane containing the metal boundary structure 2200. Thus, a balance is achieved between electromagnetic function selection and wide coverage.

[0185] Furthermore, through the electric resonant structure 2300, the electric resonant operating frequency band of the metal boundary structure 2200 and the electric resonant structure 2300 is matched with the magnetic resonant operating frequency band of the magnetic resonant structure 2100, thereby achieving unified control of signals with different polarization directions in different surfaces within the operating frequency band.

[0186] In the embodiments of this application, operating frequency band matching refers to the overlap range between the electric resonant operating frequency band and the magnetic resonant operating frequency band being greater than a first threshold. The first threshold can be 50%, 60%, 70%, 80%, 90%, etc., and this application does not limit it.

[0187] In this embodiment, by matching the electrical resonant operating frequency band of the metal boundary structure 2200 and the electrical resonant structure 2300 with the magnetic resonant operating frequency band of the magnetic resonant structure 2300, when an electromagnetic signal is incident on the filter structure 2000, the impedance matching condition between the electromagnetic signal's origin and the filter structure 2000 is met within a specific frequency band (e.g., 5G, 6G communication bands), allowing most of the electromagnetic signal's energy to pass through the filter structure 2000. In this embodiment, when impedance matching is achieved, the transmittance of the filter structure 2000 for electromagnetic signals within the frequency band is greater than a second threshold, which can be 80%, 90%, etc., and is not limited thereto in this application.

[0188] In this embodiment of the application, the filter structure 2000 is used to modulate the electromagnetic waves from the signal source (electromagnetic function selection, i.e., to realize differentiated functions on different planes), the first end of the fourth substrate is the end closer to the signal source, and the second end is the end farther away from the signal source.

[0189] The second direction pointing from the first end to the second end (i.e., the direction of the boundary line between the plane where the metal boundary structure 2200 is located and the first plane (the plane where the magnetic resonant structure 2100 is located)) can be the main lobe direction of the signal source, or it can have a certain angle with the main lobe direction of the signal source. For example, in Figure 1b, the main lobe direction of the antenna element is: based on the horizontal to the right, offset downwards by a small angle (e.g., 10°); the first direction can be horizontal to the right. The plane where the filter structure 2000 is located (i.e., the xoy plane in Figure 2, where o is the origin of the coordinate system, the y direction is the first direction, and the z direction is the second direction) also has a certain angle with the main lobe direction of the signal source, which is not limited in this application.

[0190] Optionally, the signal source can be an antenna from a different system, an antenna array, a base station, or an unknown signal source; this application does not limit this.

[0191] When the filter structure 2000 is applied to the antenna system, the electric resonant operating frequency bands of the metal boundary structure 2200 and the electric resonant structure 2300, and the magnetic resonant operating frequency band of the magnetic resonant structure 2300 are all matched with the operating frequency band of the antenna system.

[0192] Simulations were performed on the structure shown in Figure 2 to obtain the transmission amplitude characteristic curves in the TE and TM polarization modes in the xoz plane shown in Figures 7a and 7b, the transmission amplitude characteristic curve in the TE polarization mode in the yoz plane shown in Figure 7c, and the transmission amplitude curves at different incident angles shown in Figure 8.

[0193] As shown in Figure 7a, the characteristic curves of TE signals in different directions (incident angles) within the xoz plane are relatively consistent, achieving electromagnetic transmission in different directions. Assuming a transmission amplitude greater than 0.8 is considered bandpass, the transmission frequency band of the TE mode within the xoz plane is 5.3-5.8 GHz.

[0194] As shown in Figure 7b, the characteristic curves of TM signals in different directions (incident angles) within the xoz plane are relatively consistent, achieving electromagnetic transmission in different directions. Assuming a transmission amplitude greater than 0.8 is considered bandpass, the transmission frequency band of the TM mode within the xoz plane is 5.3-5.8 GHz.

[0195] Therefore, the filter structure 2000 exhibits relatively consistent transmission amplitude for signals with different incident angles (the angle between the signal direction and the z-axis) on the xoz plane under both TE and TM polarization modes. Both TE and TM modes are frequency-selective, and their transmission frequency bands are consistent.

[0196] As shown in Figure 7c, the filter structure 2000 exhibits significant differences in transmission amplitude for signals with different incident angles in the TE polarization mode (and similarly for the TM polarization mode) within the yoz plane. Taking the curve at θ = 0° as an example, an inflection point appears around 5.4 GHz. Signals with frequencies higher than this inflection point show relatively stable transmittance (e.g., the transmittance of a signal at θ = 0° stabilizes around 1 after the inflection point). The further the signal deviates from the z-axis, the greater θ becomes, and the frequency offset effect of the magnetic resonant structure 2100 on signals at angle θ increases accordingly, causing the aforementioned inflection point to shift to the lower right. As shown in Figure 8, for a signal at θ = 30°, the inflection point is around 5.6 GHz, after which the transmittance stabilizes around 0.8; for a signal at θ = 45°, the inflection point is around 6 GHz, after which the transmittance stabilizes around 0.7. Assuming a transmission amplitude greater than 0.8 is considered bandpass, and the transmission frequency band is set at 5.3-5.8 GHz, then signals with θ>45° cannot pass through the magnetic resonant structure 2100. The filter structure 2000 can achieve angle selection of signals on the yoz plane.

[0197] Applying the device shown in Figure 2 to the architecture shown in Figure 1b, the xoz plane becomes the horizontal plane and the yoz plane becomes the vertical plane. Scanning the signal in the horizontal and vertical planes yields the transmission amplitude comparison curves at different incident angles, as shown in Figure 8. Here, the incident angle is the angle between the signal direction and the z-axis direction on the corresponding plane.

[0198] As shown in Figure 8, in the horizontal plane (xoz plane), the transmission amplitudes corresponding to different incident angles are not significantly different, all above 0.8; however, in the vertical plane (yoz plane), when the incident angle (the angle between the signal direction k and the z axis) is greater than 30°, the corresponding transmission amplitude will decrease significantly, thus achieving differentiated selection characteristics in the horizontal and vertical planes.

[0199] In the structure shown in Figure 2, the electric resonant structure 2300 and the metal boundary structure 2200 can be on different substrates or on different surfaces of the same substrate. This application does not limit this.

[0200] In one example, the electrical resonant structure 2300 and the metal boundary structure 2200 are located on different substrates. For example, as shown in FIG9a, the filter structure 2000 includes at least two first substrates, a second substrate, and at least two fourth substrates.

[0201] The first substrate extends along a first direction, and at least two first substrates are periodically arranged along a plane perpendicular to the metal boundary structure. The metal boundary structure 2200 is located on the first substrate. The second substrate is located between the two first substrates, and the electric resonant structure 2300 is located on the second substrate.

[0202] The electric resonant structure 2300 and the metal boundary structure 2200 are separated by a filling medium between the first substrate and the second substrate. The filling medium can be air, foam, or other filling media, and this application does not limit its application to this type.

[0203] At least two parallel metallic boundary structures 2200 can achieve standing waves in the electric field. The electric resonant structure 2300 is an antenna structure design or an antenna-like structure design, which can adjust the standing wave frequency band, thereby achieving electric resonance through the at least two metallic boundary structures 2200 and the electric resonant structure 2300.

[0204] In this embodiment, the second substrate is not perpendicular to the first substrate. Preferably, the second substrate is parallel to the first substrate. The second substrate includes one or more electrical resonant structures 2300, which can adjust the standing wave frequency band of the metal boundary structure 2200 on the first substrate, thereby adjusting the electrical resonant operating frequency band. In this embodiment, the electrical resonant operating frequency bands of the metal boundary structure 2200 and the electrical resonant structure 2300 can be adjusted by the electrical resonant structure 2300, so that the electrical resonant operating frequency band matches the magnetic resonant operating frequency band of the magnetic resonant structure 2100.

[0205] In one example, the electrical resonant structure 2300 and the metal boundary structure 2200 are located on different surfaces of the same substrate. For example, as shown in FIG9b, the filter structure 2000 includes at least two third substrates and at least two fourth substrates. FIG9b shows only one fourth substrate to clearly illustrate the structure on both sides of the third substrate, but in reality, there are at least two fourth substrates.

[0206] At least two third substrates are periodically arranged along a direction perpendicular to the first direction (y-axis direction), with the electric resonant structure 2300 and the metal boundary structure 2200 located on different surfaces of the third substrates. Specifically, the electric resonant structure 2300 is located on the surface of the third substrate facing outwards along the paper, and the metal boundary structure 2200 is located on the surface of the third substrate facing inwards along the paper. The electric resonant structure 2300 and the metal boundary structure 2200 are separated by a dielectric in the third substrate.

[0207] In this embodiment, the electric resonant structure 2300 is used to adjust the operating frequency band of the electric resonance, thereby matching the electric resonant operating frequency band of the metal boundary structure 2200 and the electric resonant structure 2300 with the magnetic resonant operating frequency band of the magnetic resonant structure 2100.

[0208] Optionally, the electric resonant structure 2300 can be a dipole structure as shown in Figure 10a. The dipole structure includes one or more pairs of resonant metal arms on a second plane, each pair of resonant metal arms being perpendicular to the central axis and symmetrical about each other along the central axis. The central axis is parallel to a second direction, which is the direction of the boundary line between the plane containing the metal boundary structure 2200 and the first plane (the plane containing the magnetic resonant structure 2100), and the second direction is different from the first direction.

[0209] By changing the dipole spacing (i.e., the spacing between oscillators within the dipole, and also the spacing between the resonant metal arms), the passband of the metal boundary structure 2200, i.e., the passband in the TM polarization mode, can be adjusted.

[0210] Figures 11a and 11b show the transmission amplitude characteristics of TM and TE mode signals in the plane containing the metal boundary structure 2200 under different dipole spacings g. A transmittance greater than 0.8 is assumed to be bandpass.

[0211] Referring to Figure C in Figure 4, since the electric field component of the transmissible signal direction in Figure C is relatively small on the electric resonant structure 2300, the electric resonant structure 2300 has a relatively small influence on the passband of Figure C.

[0212] As shown in Figure 11a, above 5 GHz, the change in dipole spacing g has little effect on the transmission amplitude characteristic curve of the TM mode signal within the metal boundary structure 2200. The transmission frequency band corresponding to the TM mode is 5.2-6 GHz.

[0213] Referring to Figure E in Figure 4, the electric field direction of the TE mode signal in the first plane (xoz plane) is parallel to the second plane where the electric resonant structure 2300 is located. The passband of the TE mode signal in the xoz plane can be adjusted by the electrical response of the TE mode signal in the xoz plane on the electric resonant structure 2300.

[0214] As shown in Figure 11b, in TE mode, when the dipole spacing g = 1 mm, the transmission frequency band is above 5.8 GHz, which is mismatched with TM mode. Adjusting the dipole spacing to g = 2 mm shifts the transmission frequency band down to above 5.6 GHz; adjusting it to g = 0.2 mm shifts it down to above 5.4 GHz. By adjusting the dipole spacing g, the transmission frequency bands of the TE and TM modes for the electric wall response of the 2200 metallic boundary structure can be matched, thus unifying the electric resonant operating frequency band and the magnetic resonant operating frequency band.

[0215] In this embodiment, the magnetic resonant structure 2100 strengthens the magnetic field by constructing a current loop, thereby utilizing the magnetic flux response to achieve electromagnetic function selection on the plane where the metal boundary structure 2200 is located. Although the electric resonant structure 2300 shown in Figures 10a and 10b also has a loop structure, as shown in Figure B of Figure 4, since the direction of the signal's magnetic field is parallel to the second plane where the electric resonant structure 2300 is located, there is no magnetic flux of the signal on the electric resonant structure 2300. Therefore, the electric resonant structure 2300 does not affect the electromagnetic function selection of the magnetic resonant structure 2100.

[0216] The specific structure of the resonant structure 2300 can be shown in Figures a, b, and c of Figure 10b. The structure in Figure c of Figure 10b is the electric resonant structure 2300 of the dipole antenna structure used in Figure 10a. Optionally, the resonant structure 2300 can also be shown in Figure b of Figure 10b, which is a ring-shaped metal structure on the second plane.

[0217] In the embodiments of this application, in addition to adjusting the operating frequency band of the electric resonance through the electric resonance structure 2300 to achieve matching between the electric resonance operating frequency band and the magnetic resonance operating frequency band, the operating frequency band can also be adjusted through the structural dimensions to achieve frequency band matching.

[0218] Figure 12a is a top view of the filter structure 2000 in the z-axis direction. As shown in Figure 12a, the first plane of the magnetic resonant structure 2100 is in the x-axis direction, and the extension direction of the metal boundary structure 2200 (first direction) and the extension direction of the electric resonant structure 2300 (third direction) are both in the y-axis direction.

[0219] In the structure shown in Figure 12a, Px is the arrangement period of the metal boundary structure 2200. Px affects the cutoff frequency of the metal boundary structure 2200 (waveguide), thus affecting its passband. Py is the arrangement period of the magnetic resonant structure 2100. Py affects the magnetic resonant period of the magnetic resonant structure 2100, thus affecting its response frequency and passband. The operating frequency bands of the electric and magnetic resonances can be adjusted by adjusting Px and Py, allowing the two passbands to match.

[0220] In this embodiment, multiple parallel metallic boundary structures 2200 can constitute a waveguide structure. On the plane (yoz plane) where the metallic boundary structures 2200 are located, signals with small angles to the second direction (z-axis direction) can be transmitted, while signals with larger angles are suppressed. This results in low signal transmittance on the yoz plane. The electrical resonant structure 2300 enables resonance of the signal within its operating frequency band, guiding the signal on the yoz plane and thereby enhancing its strength, thus improving transmission characteristics.

[0221] In this embodiment, the plane containing the electric resonant structure 2300 is not perpendicular to the metal boundary structure 2200. In another example, Figure 12b is a top view of the filter structure 2000 along the z-axis. As shown in Figure 12b, the plane containing the electric resonant structure 2300 is perpendicular to the plane containing the magnetic resonant structure 2100 along the x-axis, and along the y-axis in the xoy plane. The angle between the metal boundary structure 2200 and the magnetic resonant structure 2100 is 45°, along the 45° angle with the x-axis in the xoy plane.

[0222] In this embodiment, the filter structure 2000 can be configured as an array structure to expand the size of the filter structure 2000 that can perform electromagnetic function selection. As shown in Figure 13a, xoz is the plane where the magnetic resonant structure 2100 is located. yoz is the plane where the metal boundary structure 2200 and the electric resonant structure 2300 are located.

[0223] As shown in Figure 13b, multiple magnetic resonant structures 2100 can be disposed in the fourth direction of the fourth substrate (the fourth direction is the direction perpendicular to the second direction on the plane where the fourth substrate is located, i.e., the x-axis direction in Figure 13a). The second direction of the fourth substrate also includes multiple second slots. These second slots are used to fix multiple metal boundary structures 2200 arranged along the fourth direction (x-axis direction).

[0224] As shown in Figure 13a, multiple parallel magnetic resonant structures 2100 can be arranged in the first direction (y-axis direction). The extension direction (first direction) of the multiple metal boundary structures 2200 is the y-axis direction in Figure 13a.

[0225] As shown in Figure 14a, along the y-axis direction, the second / third substrate includes multiple electrical resonant structures 2300. The second / third substrate also includes multiple first slots along the y-axis direction. These first slots are used to fix multiple fourth substrates along the y-axis direction.

[0226] Optionally, along the z-axis, the second / third substrate may include one or more rows of first slots for mounting the fourth substrate. For example, if there are two rows of first slots along the z-axis, then the two first slots along the z-axis are used to mount one fourth substrate. The 2N first slots 2320 on the second / third substrate are used to mount N fourth substrates.

[0227] Optionally, multiple second / third substrates can be arranged periodically in the x-axis direction.

[0228] The electric resonant structure 2300 on the second / third substrate can be a conductor structure disposed on a dielectric substrate. The conductor structure can be a dipole structure as shown in Figure 9a.

[0229] As shown in Figure 14a, the second / third substrate extends along a first direction (y-axis direction). The second / third substrate includes a plurality of electrical resonant structures 2300 along the y-axis direction. Each electrical resonant structure 2300 includes one or more pairs of resonant metal arms. The resonant metal arms are perpendicular to the central axis and symmetrical about each other along the central axis. The central axis is parallel to the second direction (z-axis direction).

[0230] For example, as shown in Figure 14a, the central axis of the electric resonant structure 2300 is the axis of symmetry in the z-axis direction. The electric resonant structure 2300 is symmetrical about this axis of symmetry. The resonant metal arm of the electric resonant structure 2300 is a metal extending in the y-axis direction.

[0231] Optionally, the extension direction of the second substrate may also deviate from the first direction, as long as it is not perpendicular to the first direction, so that the electric resonant structure 2300 has a projection component on the plane (yoz plane) where the metal boundary structure 2200 is located; the central axis of the electric resonant structure 2300 may also not be in the second direction, as long as it is not perpendicular to the second direction, and this application does not limit this.

[0232] In the embodiments of this application, the conductor structure forming the electric resonant structure 2300 on the second substrate / third substrate can be any structure other than the dipole structure shown in FIG14a.

[0233] For example, as shown in Figure 14b, multiple electrical resonant structures 2300 can share a conductor region extending in the y-axis direction. As shown in Figure 14b, each electrical resonant structure 2300 also includes two small conductor regions located in the positive and negative directions (positive and negative directions of the z-axis) of the first direction of the conductor region.

[0234] Alternatively, as shown in Figure 14c, each electric resonant structure 2300 includes a small conductor region, a large conductor region, and another small conductor region arranged sequentially along the z-axis. The large conductor region can be an "I-shape" as shown in Figure 14c, or two symmetrical "C-shapes" along the z-axis, etc. Regardless of whether it is an "I-shape," a "C-shape," or any other shape, the large conductor region constitutes a dipole-like oscillator structure.

[0235] In the embodiments of this application, the filter structure 2000 can be combined with the antenna element to achieve three-dimensional electromagnetic function selection of the signal radiated by the antenna element. The antenna element can be an antenna or an antenna array, and this application does not limit its application to this.

[0236] Taking an antenna array as an example, as shown in Figure 15a, the antenna system includes a filter structure 20000 and an antenna array. The filter structure 2000 is located in the first direction of the antenna array. The first direction is from the first end to the second end of the filter structure 2000, and is close to the main lobe direction of the antenna array signal.

[0237] In Figure 15a, the filter structure 2000 is parallel to the antenna array. The yoz plane is the plane containing the metallic boundary structure 2200 of the filter structure 2000, which is also a vertical plane. The xoz plane is the plane containing the magnetic resonant structure 2100 of the filter structure 2000, which is also a horizontal plane. The filter structure 2000 can achieve angle selection of the signal in the yoz plane (vertical plane) and frequency selection of the signal in the xoz plane (horizontal plane).

[0238] Therefore, as shown in Figure 15a, the antenna system can transmit signals in all directions on the horizontal plane and transmit signals within a specific angular range on the vertical plane, thereby achieving directional selection of the signals emitted by the antenna element within the vertical plane.

[0239] Figure 15b shows a schematic diagram of the signal strength before and after adding the filter structure 2000 to the antenna array. The length in the figure represents the signal strength in the corresponding direction; the longer the length, the stronger the signal. Assuming the angle selection range of the filter structure 2000 in the vertical plane is ±30° (i.e., signals with an absolute value less than 30° between the yoz plane and the z-axis can be transmitted), as shown in Figure 15b, the filter structure 2000 can suppress signals in the yoz plane with an angle greater than 30° to the z-axis, thereby suppressing signals above 30° horizontally and preventing signal interference from the antenna array to communication between different systems at higher altitudes.

[0240] Optionally, in the scenarios shown in Figures 15a and 15b, the antenna elements in the antenna array can be distributed in the xoy plane as shown in Figure 15c. As shown in the right image of Figure 15c, the direction of the antenna elements is parallel to the fourth direction (i.e., the x-axis direction in Figure 15a); or as shown in the left image of Figure 15c, the antenna elements can also form a 45° angle with the fourth direction, or other angles, which are not limited in this application.

[0241] In this embodiment, the filter structure 2000 can also be used to suppress sidelobes. As shown in Figure 16a, the electromagnetic fields of adjacent elements on the antenna array interfere with each other, and the corresponding radiation pattern is shown in the left image of Figure 16a.

[0242] If the filtering structure 2000 provided in this embodiment is set in the signal transmission direction (second direction) of the antenna array, as shown in the right figure of Figure 16a, the filtering structure 2000 can suppress signal transmission with a large angle between the yoz plane (i.e., the paper plane of Figure 16a) and the z-axis direction (i.e., the vertical direction in Figure 16a), causing signals with large angles to be reflected. Therefore, the signals from different elements radiate at an emission angle close to the z-axis direction (vertical direction), and the interference of the electromagnetic fields between the elements is weakened. As shown in Figure 16b, the filtering structure 2000 can significantly suppress the sidelobes of the antenna array, achieving the filtering out of sidelobe signals.

[0243] It is worth noting that Figure 16a is a qualitative representation of the electromagnetic field signal intensity and does not constitute a quantitative limitation on the specific intensity of the electromagnetic field signal.

[0244] In the embodiments of this application, the magnetic resonant structure 2100 can be of various forms, such as the several typical structures shown in Figure 17.

[0245] In Figure 17, the dark bottom surface represents the conductor layer on the surface of the fourth substrate, the light-colored gaps represent the non-conductor gaps on the conductor layer, and the light-colored squares are the second slots used to fix the first substrate.

[0246] Each of the arbitrary magnetic resonant structures 2100 includes a first gap that passes through the first end but not through the second end, and a second gap that passes through the second end but not through the first end.

[0247] As shown in magnetic resonant structures A and B in Figure 17, the fourth substrate includes at least one gap (one in the example of Figure 17, but more) between its first and second ends. To ensure signal coupling from the first end to the second end (from bottom to top in Figure 17), the projections of adjacent gaps along the fourth direction (the x-axis direction, i.e., left-right direction in Figure 17) in the first gap, the second gap, and at least one gap (excluding the first and second gaps) include overlapping portions. For example, in magnetic resonant structure B of Figure 17, the lower end of the middle gap overlaps with the upper end of the right gap along the fourth direction (x-direction).

[0248] If only the first gap and the second gap are included, then the first gap and the second gap may not be collinear along the second direction, and the projections of the first gap and the second gap along the fourth direction include the overlapping parts.

[0249] Alternatively, as shown in the magnetic resonant structure C in Figure 17, the first and second slits can be collinear along the second direction. If at least one slit other than the first and second slits is included, the first slit, the second slit, and at least one slit can also be collinear along the second direction.

[0250] On the fourth substrate, the second slot 2160 is wider and can be used to fix the first substrate in the form of a metal plate, or to fix the hollow first substrate. For example, as shown in Figure 18a, the first substrate includes a metal shell and a hollow cavity. The metal shell is the metal boundary structure 2200, and the extension direction of the hollow cavity is the first direction (the y-axis direction in Figure 18a).

[0251] In this embodiment, the hollow first substrate structure allows for the placement of signal lines and other transmission media within the cavity, while a metal casing provides shielding to prevent signal leakage from the transmission media. This allows for the accommodation of more signal transmission paths.

[0252] Optionally, the metal boundary structure 2200 can also achieve an electric wall response using multiple metal strips. As shown in Figure 18b, the first / third substrate includes a non-metallic substrate and multiple metal strips located on the surface of the non-metallic substrate. The multiple metal strips are arranged along a second direction (z-direction in Figure 18b) and extend along a first direction (y-direction in Figure 18b). The multiple metal strips constitute the metal boundary structure 2200.

[0253] Optionally, the metal strip can be a long strip-shaped metal structure with a certain width, or it can be a metal wire, or a long strip-shaped metal structure composed of multiple metal wires spliced ​​together. This application does not limit this.

[0254] In this embodiment, multiple metal strips on the first / third substrate are used to effectively achieve the electric wall response of the complete metal boundary, thereby enabling differentiated electromagnetic function selection for signals on different planes. The metal strips can effectively control the electromagnetic field distribution on the metal boundary structure 2200, enhancing the signal strength on the metal boundary structure 2200 and thus improving transmission characteristics.

[0255] Furthermore, the metal strips on the first / third substrate can also work with the electric resonant structure 2300 to adjust the conduction frequency band of the metal boundary structure 2200 so that the electric resonant operating frequency band is consistent with the magnetic resonant operating frequency band.

[0256] In one alternative design, a first / third substrate comprising multiple metal strips is a printed circuit board (PCB), and a non-metallic substrate serves as the substrate for the PCB. Compared to a completely metal surface, the first / third substrate composed of PCBs is lighter, which can reduce the weight of the device.

[0257] In the embodiments of this application, the structure of multiple parallel non-conductive gaps has gaps extending in the same direction and coinciding with the direction of signal transmission, resulting in higher coupling efficiency.

[0258] In this embodiment, the shape of the conductor region in the magnetic resonant structure 2100 is not limited. The conductor region can be the conductor region adjacent to the non-conductor gap as shown in FIG17, or it can be a conductor region with a clear boundary.

[0259] As shown in Figure 19a, the surface of the fourth substrate is non-conductive, and multiple conductive rings are included on the surface of the fourth substrate. Each conductive ring includes an opening. The direction in which the geometric center of the conductive ring points to the opening of the conductive ring is called the opening direction of the conductive ring.

[0260] The magnetic resonant structure 2100 has multiple conducting rings with different opening directions. At least two of the conducting rings have openings facing different directions. For example, Figure 19a includes two conducting rings facing upwards and downwards. Due to the different opening directions, the excitation currents in the different conducting rings have different directions. This is because the different opening directions create a phase abrupt change, resulting in reverse currents in the two conducting rings. This structure is also called a split ring resonator (SRR) or a ring magnetic resonant frequency-selective structure.

[0261] Within a single conducting ring, the opening couples the signal in the form of a capacitor, forming an LC resonance. Since the openings of the two conducting rings face opposite directions, the two conducting rings are equivalent to parallel-plate capacitors, causing the two conducting rings to generate LC resonance. The region between the two conducting rings (i.e., the gap between the two conducting rings) is the location of local field reinforcement.

[0262] As shown in Figure 19b, the outer conducting ring A and the inner conducting ring B have different opening orientations and opposite current directions. Taking the conducting region on the left side of the two conducting rings in Figure 19b as an example, the reinforcement of the local field is illustrated. The outer conducting ring A is larger; therefore, in Figure 19b, three vertical points represent the magnetic field of conducting ring A facing outwards from the paper, and three vertical crosses represent the magnetic field of conducting ring A facing inwards from the paper. The inner conducting ring B is smaller; therefore, in Figure 19b, two vertical points represent the magnetic field of conducting ring B facing outwards from the paper, and two vertical crosses represent the magnetic field of conducting ring B facing inwards from the paper.

[0263] As shown in Figure 19b, within the region of conductor ring B, the magnetic field generated by conductor ring A faces inwards towards the plane of the paper, while the magnetic field generated by conductor ring B faces outwards towards the plane of the paper, thus canceling each other out. Outside conductor ring A, the magnetic field generated by conductor ring A faces outwards towards the plane of the paper, while the magnetic field generated by conductor ring B faces inwards towards the plane of the paper, again canceling each other out. In the region between conductor rings (i.e., the gap between the two conductor rings), the magnetic fields generated by both conductor rings A and B face inwards towards the plane of the paper, resulting in a strengthened magnetic field. The gap between the conductor rings is thus a region of localized field reinforcement.

[0264] Therefore, by utilizing the magnetic response of the gap region (local field reinforcement region) between the conductor rings, and following the principle shown in Figure 4, different magnetic flux response characteristics can be achieved for the TE mode signal (Figure B in Figure 4) in the plane containing the metal boundary structure 2200 and the TM mode signal (Figure F in Figure 4) in the plane containing the magnetic resonant structure 2100 (the first plane). This allows for electromagnetic function selection of the TE signal in the plane containing the metal boundary structure 2200 and electromagnetic transparency of the TM signal in the first plane. Combined with the electric wall response of the metal boundary structure 2200, electromagnetic function selection of the TM signal in the plane containing the metal boundary structure 2200 and electromagnetic transparency of the TE signal in the first plane can be achieved. This results in differentiation in the electromagnetic function selection of signals in the first plane and the plane containing the metal boundary structure 2200.

[0265] Figure 20 shows different arrangements of multiple conductor rings on the magnetic resonant structure 2100. The multiple conductor rings can be the nested magnetic resonant structure D in Figure 20, the magnetic resonant structure E with openings facing away from each other, or the magnetic resonant structure F with openings facing each other.

[0266] Based on the architecture and magnetic resonant structure D shown in Figure 15a, a specific frequency of 8 GHz is selected. The signal of the antenna element is scanned in the horizontal plane (xoz plane) and the vertical plane (yoz plane), and the transmission amplitude comparison curves at different incident angles shown in Figure 21 can be obtained.

[0267] As shown in Figure 21, in the horizontal plane (xoz plane), the transmission amplitude of different incident angles is not significantly different, and is all above 0.8; however, in the vertical plane (yoz plane), when the incident angle (the angle between the signal direction k and the z axis) is greater than 30°, the transmission amplitude will decrease significantly, and is all below 0.8.

[0268] In the embodiments of this application, the conductor ring can be a square ring as shown in Figures 19a-20, a circular ring as shown in Figure 22, or a ring of other shapes; this application does not limit the number of such rings. The number of conductor rings can be two, three, or more; this application does not limit the number of such rings.

[0269] In a preferred embodiment, the magnetic resonant structure 2100 includes a plurality of conductor rings, including conductor ring A and conductor ring B, with conductor ring A and conductor ring B having opposite opening directions.

[0270] Optionally, the plurality of conductor rings may also include conductor ring C and conductor ring D. Conductor ring C and conductor ring A have the same opening direction, and conductor ring D and conductor ring B have the same opening direction.

[0271] Alternatively, the opening directions of conductor rings C and D are opposite and different from the opening directions of conductor rings A and B.

[0272] In the embodiments of this application, the magnetic resonant structure 2100, which includes multiple conductor rings, can not only achieve angle selection of the TE signal on the first plane, but also phase / amplitude selection of the signal.

[0273] In the magnetic resonant structure 2100, the transmission phase of the signal is related to the direction of the line connecting the openings of the conductor rings. The direction through which the openings of the multiple conductor rings in the magnetic resonant structure 2100 pass is called the direction of the line connecting the openings of the magnetic resonant structure. As shown in Figure 23, φ is the angle between the direction of the line connecting the openings of the conductor rings in the magnetic resonant structure 2100 and the second direction (z-axis direction). Different φ values ​​correspond to different transmission phases.

[0274] In this embodiment, the fourth substrate along the fourth direction (x-direction) may include multiple magnetic resonant structures 2100, and the opening connection directions (of the conductor rings) of different magnetic resonant structures 2100 in the second direction are not parallel to each other. For example, as shown in FIG24a, the opening connection directions of the conductor rings on different magnetic resonant structures 2100 are indicated by dashed lines. The opening connection directions of different magnetic resonant structures 2100 in the fourth direction exhibit a gradient change. The phase adjustment of different regions in the fourth direction is achieved through the gradient change of the opening connection directions, thereby adjusting the direction of incoming wave refraction and changing the beam direction.

[0275] When an electromagnetic wave is incident at an angle of 60 degrees onto an SRR ring structure with different opening directions, as shown in the left image of Figure 25, as the opening direction φ changes, the amplitude of the signal passing through the filter structure 2000 in the vertical plane (xoy plane) changes relatively little, but the phase of the filter structure 2000 changes significantly. Therefore, an electromagnetic pattern with gradient phase change can be achieved by controlling the gradient arrangement of the opening directions of the SRR ring structure in the second direction (x-axis direction). This design allows for the artificial modulation of the main beam direction of the electromagnetic wave.

[0276] Optionally, the amplitude of the signal can be controlled by adjusting the phase transmission amplitude to achieve amplitude modulation of the signal in the fourth direction.

[0277] In one example, phase selection can be applied to the waveform adjustment schemes shown in Figures 16a and 16b. The fourth direction in Figure 24a corresponds to the horizontal direction in Figures 16a and 16b. Before the filter structure 2000 is loaded, the radiation pattern of the antenna array is shown in the left image of Figure 16a, which includes multiple high-energy sidelobes (referred to as higher sidelobes) in addition to the main lobe located in the center. These higher sidelobes are distributed along the second direction. The higher sidelobes are generated because the signal from the oscillator causes interference and phase expansion at the higher sidelobes.

[0278] Based on the magnetic resonant structure 2100 shown in Figure 24a, gradient phase change is achieved through the gradient arrangement of multiple SRR ring structure openings in the fourth direction, thereby adjusting the phase distribution of the oscillator signal in the fourth direction. This eliminates signal interference at higher sidelobes, suppressing higher sidelobes, resulting in the radiation pattern shown on the right in Figure 16a.

[0279] In the embodiments of this application, the spatial position where energy interference enhancement occurs can also be adjusted by phase synthesis modulation and / or amplitude synthesis modulation, thereby controlling / changing the direction of the beam main lobe.

[0280] It is worth noting that, in addition to causing a gradient change in the direction of the opening connection of different magnetic resonant structures 2100 in the fourth direction, the gradient change of different magnetic resonant structures 2100 in the fourth direction can also be reflected in the diameter of the conductor ring shown in Figure 24b, the opening size of the conductor ring shown in Figure 24c, or the spacing between the conductor rings, so as to achieve phase modulation in different regions in the fourth direction.

[0281] Figure 26 shows the S21 curves corresponding to different opening sizes of the open ring. As shown in Figure 26, by controlling the opening size of the conductor ring, the frequency position of the resonant peak can be controlled, thereby achieving gradient adjustment of the transmission amplitude.

[0282] It is worth noting that the gradient variation of different magnetic resonant structures 2100 in the fourth direction mentioned above can be reflected in one or more aspects of the opening direction, diameter, opening size, and spacing of the conductor ring, and this application does not limit this.

[0283] In this embodiment, amplitude modulation can also be achieved for the filter structure 2000 including non-conductor gaps on the magnetic resonant structure 2100. On the magnetic resonant structure 2100, the transmission amplitude of the signal is related to the thickness, length, and spacing of the non-conductor gaps. Amplitude modulation is achieved by stepping the gap thickness / length / gap spacing of different non-conductor gaps in the fourth direction.

[0284] The gradient variation of different magnetic resonant structures 2100 in the fourth direction can be reflected in the thickness of the non-conductor gap shown in Figure 27a, the length of the non-conductor gap shown in Figure 27b, and the spacing of the non-conductor gap shown in Figure 27c, so as to achieve amplitude modulation in different regions in the fourth direction.

[0285] In one example, amplitude selection can be applied to the waveform adjustment schemes shown in Figures 16a and 16b. The fourth direction in Figures 27a-27c corresponds to the horizontal direction in Figure 16a. Before the filter structure 2000 is loaded, the radiation pattern of the antenna array is shown in the left image of Figure 16a, which includes multiple sidelobes in addition to the main lobe located in the center.

[0286] Based on the magnetic resonant structure 2100 shown in any of the embodiments in Figures 27a-27c, the non-conductor gap at the location of the stronger sidelobe is narrowed / shortened / spaced, thereby reducing the amplitude at the stronger sidelobe. This achieves suppression of the energy of the stronger sidelobe, resulting in the radiation pattern shown in the right figure of Figure 16a.

[0287] It is worth noting that Figure 27a illustrates the different thicknesses of non-conductor gaps in different regions along the fourth direction using parallel non-conductor regions on the conductor layer as an example, but this does not limit the form of the non-conductor gaps. The non-conductor gaps can also be the non-conductor gaps between adjacent conductor rings shown in Figures 19a, 19b, 20, and 22. In this structure, the thickness of the non-conductor gap depends on the radius difference between adjacent conductor rings.

[0288] It is worth noting that the gradient variation of different magnetic resonant structures 2100 in the fourth direction mentioned above can be reflected in one or more aspects of the thickness, length, and spacing of the non-conductor gap, and this application does not limit this.

[0289] Applying the filter structure 2000 shown in Figures 2 to 27c to the filter structure shown in Figure 1b yields the antenna system provided in this embodiment. In this system, the filter structure is located in the second direction (i.e., the main lobe direction) of the antenna element.

[0290] Optionally, the antenna system may also include a support structure for fixing the antenna elements and the filtering structure.

[0291] The antenna system provided in this application embodiment can be applied to electronic devices such as base stations, remote radio units (RRUs) of base stations, and routers, thereby realizing the radiation of electromagnetic energy.

[0292] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0293] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between apparatuses or units through some interfaces, and may be electrical, mechanical, or other forms.

[0294] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0295] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0296] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

Claims

1. A filtering structure, characterized in that, It includes at least two magnetic resonant structures, at least two metallic boundary structures, and an electric resonant structure; The magnetic resonant structure includes a conductor region on a first plane, the conductor region including an opening, and at least two of the magnetic resonant structures are periodically arranged along a direction perpendicular to the first plane; The metal boundary structure includes a metal sheet or metal strip extending along a first direction, and at least two of the metal boundary structures are periodically arranged along a direction perpendicular to the plane in which the metal boundary structure is located, wherein the first direction is not parallel to the first plane. The electric resonant structure is located between the two metal boundary structures, and the electric resonant structure has a projection component on the plane where the metal boundary structures are located. The electric resonant structure and the metal boundary structures are separated by a dielectric. The electric resonant operating frequency band of the metal boundary structure and the electric resonant structure matches the magnetic resonant operating frequency band of the magnetic resonant structure.

2. The filtering structure according to claim 1, characterized in that, The filtering structure is applied to the antenna system, and both the electrical resonant operating frequency band and the magnetic resonant operating frequency band are matched with the operating frequency band of the antenna system.

3. The filtering structure according to claim 1 or 2, characterized in that, The electric resonant structure includes: One or more pairs of resonant metal arms, each pair of resonant metal arms being perpendicular to and symmetrical about the central axis, the central axis being parallel to a second direction, the second direction being the direction of the boundary line between the plane containing the metal boundary structure and the first plane, and the second direction being different from the first direction; or... Ring-shaped metal structure.

4. The filtering structure according to any one of claims 1 to 3, characterized in that, The filtering structure includes at least two first substrates and a second substrate; The metal boundary structure is located on the first substrate, the first substrate extends along the first direction, and at least two of the first substrates are periodically arranged along a direction perpendicular to the plane where the metal boundary structure is located. The second substrate is located between the two first substrates, and the electric resonant structure is located on the second substrate; The electric resonant structure and the metal boundary structure are separated by a filling medium between the first substrate and the second substrate.

5. The filtering structure according to claim 4, characterized in that, The second substrate extends along a third direction, which is not parallel to either the first direction or the second direction.

6. The filtering structure according to claim 4 or 5, characterized in that, The second substrate is parallel to the first substrate.

7. The filtering structure according to any one of claims 1 to 6, characterized in that, The filtering structure includes at least two third substrates; At least two of the third substrates are periodically arranged along a direction perpendicular to the plane of the metal boundary structure, and the electric resonant structure and the metal boundary structure are located on different surfaces of the third substrates; The electric resonant structure is separated from the metal boundary structure by a dielectric in the third substrate.

8. The filtering structure according to any one of claims 1 to 7, characterized in that, The magnetic resonant structure includes at least two conductor regions with different opening directions. The direction of the line connecting the openings of the different conductor regions of the magnetic resonant structure is not perpendicular to the second direction, which is the direction of the boundary line between the plane where the metal boundary structure is located and the first plane.

9. The filtering structure according to claim 8, characterized in that, The magnetic resonant structure has at least two conductor regions, including a conductor region whose opening direction is not perpendicular to the second direction.

10. The filtering structure according to any one of claims 1 to 9, characterized in that, The filtering structure includes a fourth substrate, the surface of which is located in the first plane, and the magnetic resonant structure includes the conductor region located on the surface of the fourth substrate.

11. The filtering structure according to claim 10, characterized in that, The second substrate also includes a first slot, and the fourth substrate is connected to the second substrate through the first slot.

12. The filtering structure according to claim 10 or 11, characterized in that, The fourth substrate has two ends along the second direction, which are the first end and the second end; The magnetic resonant structure includes a first conductor region and a second conductor region. A first gap is formed on the first conductor region, the first gap passes through the first end but not through the second end, and the opening of the first conductor region faces the first end; A second gap is provided on the second conductor region, the second gap passes through the second end but not through the first end, and the opening of the second conductor region faces the second end.

13. The filtering structure according to claim 12, characterized in that, The extension directions of the first gap and the second gap are parallel to the second direction.

14. The filtering structure according to claim 13, characterized in that: The first gap and the second gap are collinear along the second direction; or, The first gap and the second gap are not collinear along the second direction, and the projections of the first gap and the second gap along the fourth direction respectively include overlapping portions, wherein the fourth direction is a direction on the fourth substrate perpendicular to the second direction; or... The first gap and the second gap are not collinear along the second direction, and there is at least one gap between the first end and the second end in addition to the first gap and the second gap. Among the first gap, the second gap and the at least one gap, the projections of two adjacent gaps along the fourth direction include overlapping portions.

15. The filtering structure according to claim 10 or 11, characterized in that, The magnetic resonant structure includes at least two conductor regions, including at least two conductor rings on the fourth substrate, each conductor ring including an opening; The at least two conductor rings include at least two conductor rings with different opening directions.

16. The filtering structure according to claim 15, characterized in that, The at least two conductor rings include a first conductor ring and a second conductor ring with opposite opening directions.

17. The filtering structure according to claim 15 or 16, characterized in that, The at least two conductor rings include a conductor ring facing a first end and a conductor ring facing a second end, the first end and the second end being the two ends of the fourth substrate along the second direction.

18. The filtering structure according to any one of claims 15 to 17, characterized in that, The fourth substrate includes at least two magnetic resonant structures distributed along a fourth direction, wherein the fourth direction is a direction on the fourth substrate that is perpendicular to the second direction. The at least two magnetic resonant structures in the fourth direction include at least two magnetic resonant structures with different opening connection directions, wherein the opening connection direction is the connection direction of the openings of at least two conductor rings in the magnetic resonant structure.

19. The filtering structure according to any one of claims 15 to 18, characterized in that, The at least two conductor rings are nested inside and outside.

20. The filtering structure according to any one of claims 10 to 19, characterized in that, The fourth substrate further includes a second slot, through which the first substrate or the third substrate is connected to the fourth substrate.

21. The filtering structure according to any one of claims 1 to 20, characterized in that, The metal boundary structure is perpendicular to the first plane.

22. The filtering structure according to any one of claims 1 to 21, characterized in that, The metal boundary structure includes at least two metal strips arranged along a second direction, the at least two metal strips extending along a first direction, the second direction being the direction of the boundary line between the plane containing the metal boundary structure and the first plane.

23. The filtering structure according to any one of claims 4 to 22, characterized in that, The first substrate includes a metal shell and a hollow cavity extending along the first direction, wherein the metal shell is the metal boundary structure.

24. The filtering structure according to any one of claims 1 to 23, characterized in that, The matching of the electrical resonant operating frequency band with the magnetic resonant operating frequency band includes: The overlap between the electric resonant operating frequency band and the magnetic resonant operating frequency band is greater than or equal to a first threshold, and the first threshold is greater than or equal to 50%.

25. An antenna system, characterized in that, It includes an antenna unit and a filter structure, wherein the filter structure is the filter structure according to any one of claims 1 to 24; In the filtering structure, the direction of the boundary line between the metal boundary structure and the first plane is the second direction, and the antenna element is located in the second direction of the filtering structure.

26. The antenna system according to claim 25, characterized in that, It also includes a support member for fixing the antenna unit and the filter structure.

27. An electronic device, characterized in that, Includes an antenna system, wherein the antenna system is the antenna system described in claim 25 or 26.

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