Antenna units and window glass

Abstract

Provided is an antenna unit that in use is placed so as to face a window glass for a building. The antenna unit comprises: a radiating element; a phase control member that is located on an outdoor side of the radiating element and that controls the phase of radio waves emitted from the radiating element; and a conductor that is located on an indoor side of the radiating element. The phase control member has a dielectric and a plurality of conductor parts. Also provided is a window glass comprising the antenna unit.

Description

[Technical field]

[0001] The present disclosure relates to an antenna unit and a window glass. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there is known a technique for improving radio wave transmission performance by using a radio wave transmitting body having a three-layer structure that covers an antenna as a building finishing material (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 6-196915 Summary of the Invention [Problem to be solved by the invention]

[0004] A planar antenna such as a microstrip antenna strongly radiates radio waves in the front direction. However, as shown in Fig. 1, if a dielectric material (e.g., a window glass 200) with a relatively high relative dielectric constant is in front of (in front of) the planar antenna 100, the radio waves are reflected at the interface of the dielectric material (the window glass 200), and the gain (e.g., a grating lobe) other than the main lobe of the planar antenna 100 becomes large. As a result, the main lobe of the planar antenna 100 may become weak. Note that the main lobe represents the gain of radio waves radiated downward (e.g., in the depression direction) with respect to the front direction of the planar antenna 100 or the antenna unit, and the grating lobe represents the gain of radio waves radiated upward (e.g., in the elevation direction) with respect to the front direction of the planar antenna 100 or the antenna unit.

[0005] The present disclosure provides an antenna unit and window glass that have a small grating lobe and a large main lobe, resulting in a large gain difference between the main lobe and the grating lobe. [Means for solving the problem]

[0006] The present disclosure relates to An antenna unit that is installed facing a window glass for a building, A radiating element; a phase control member that is located on the outdoor side of the radiating element and controls the phase of radio waves radiated from the radiating element; a conductor located on the indoor side of the radiating element; The present disclosure provides an antenna unit, in which the phase-shift control member is a member having a dielectric and a plurality of conductor portions.The present disclosure also provides a window glass including the antenna unit. Effect of the Invention

[0007] According to the technique of the present disclosure, the radiation direction of the radio waves radiated from the radiating element can be changed, so that the gain difference between the main lobe and the grating lobe can be increased. [Brief description of the drawings]

[0008] [Figure 1] FIG. 13 is a diagram illustrating a case where a window glass is provided in front of the planar antenna. [Diagram 2] FIG. 2 is a cross-sectional view showing a schematic example of a laminated structure of a window glass with an antenna unit according to the first embodiment. [Diagram 3] FIG. 11 is a cross-sectional view showing a schematic example of a laminated structure of a window glass with an antenna unit according to a second embodiment. [Figure 4] FIG. 11 is a cross-sectional view showing a schematic example of a laminated structure of a window glass with an antenna unit according to a third embodiment. [Diagram 5] FIG. 11 is a cross-sectional view showing a schematic example of a laminated structure of a window glass with an antenna unit according to a fourth embodiment. [Figure 6] FIG. 13 is a cross-sectional view showing a schematic example of a laminated structure of a window glass with an antenna unit according to a fifth embodiment. [Figure 7]FIG. 13 is a cross-sectional view showing a schematic example of a laminated structure of a window glass with an antenna unit according to a sixth embodiment. [Figure 8] 1 is a perspective view showing a specific example of the configuration of an antenna unit in the present embodiment. [Figure 9] 2 is a plan view showing a specific example of an antenna unit in the present embodiment. FIG. [Figure 10] 10 is a plan view showing the configuration of a microstrip array antenna in the antenna unit shown in FIG. [Figure 11] 10 is a plan view showing a configuration of a phase control member in the antenna unit shown in FIG. [Figure 12] FIG. 10 is a diagram showing an example of the results of simulating the gain difference between a main lobe and a grating lobe obtained by out-of-phase feeding when A / B=1.0 in the antenna unit shown in FIG. [Figure 13] FIG. 10 is a diagram showing an example of the results of a simulation of the relationship between the gain difference between a main lobe and a grating lobe obtained by reverse-phase feeding in the antenna unit shown in FIG. 9 and A / B. [Figure 14] FIG. 10 is a diagram showing an example of the results of simulating the gain difference between a main lobe and a grating lobe obtained by phase difference feeding when A / B=1.0 in the antenna unit shown in FIG. [Figure 15] FIG. 10 is a diagram showing an example of the results of a simulation of the relationship between the gain difference between a main lobe and a grating lobe obtained by phase difference feeding in the antenna unit shown in FIG. 9 and A / B. [Figure 16] FIG. 13 shows an antenna unit facing a multi-layered window glass. [Figure 17] FIG. 17 is a diagram showing an example of the results of a simulation of the gain obtained by phase difference feeding when A / B=1.0 in the case where a phase control member is provided in the antenna unit of FIG. 16. [Figure 18] FIG. 17 is a diagram showing an example of the results of simulating the gain obtained when A / B=1.0 in the antenna unit of FIG. 16 in the case where there is no phase control member. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment will be described with reference to the drawings. For ease of understanding, the scale of each member in the drawings may differ from the actual scale. In this specification, a three-dimensional orthogonal coordinate system with three axial directions (X-axis, Y-axis, and Z-axis) is used, and the width direction of the glass plate is defined as the X-axis direction, the thickness direction is defined as the Y-axis direction, and the height direction is defined as the Z-axis direction. The direction from the bottom to the top of the glass plate is defined as the +Z-axis direction, and the opposite direction is defined as the -Z-axis direction. In the following description, the +Z-axis direction may be referred to as up, and the -Z-axis direction may be referred to as down.

[0010] The X-axis, Y-axis, and Z-axis directions respectively represent directions parallel to the X-axis, Y-axis, and Z-axis. The X-axis, Y-axis, and Z-axis directions are perpendicular to each other. The XY plane, YZ plane, and ZX plane respectively represent imaginary planes parallel to the X-axis and Y-axis directions, imaginary planes parallel to the Y-axis and Z-axis directions, and imaginary planes parallel to the Z-axis and X-axis directions.

[0011] Fig. 2 is a cross-sectional view showing a schematic example of a laminated structure of a window glass with an antenna unit according to the first embodiment. A window glass with an antenna unit 301 shown in Fig. 2 includes an antenna unit 101 and a window glass 201. The antenna unit 101 is installed and used so as to face the indoor surface of the window glass 201 for a building.

[0012] The window glass 201 is a glass sheet used in windows of buildings and the like. The window glass 201 is formed, for example, in a rectangular shape in a plan view in the Y-axis direction, and has a first glass surface and a second glass surface. The thickness of the window glass 201 is set according to the required specifications of a building and the like. In this embodiment, the first glass surface of the window glass 201 is the surface facing the outside, and the second glass surface is the surface facing the inside. Note that in this embodiment, the first glass surface and the second glass surface may be collectively simply referred to as the main surface. In this embodiment, the rectangle includes not only a rectangle and a square, but also a rectangle or a square with chamfered corners. The shape of the window glass 201 in a plan view is not limited to a rectangle, and may be another shape such as a circle.

[0013] The window glass 201 is not limited to a single plate, and may be laminated glass, double-insulated glass, or low-e glass. Low-e glass is also called low-emissivity glass, and may be a glass in which a coating layer (transparent conductive film) having a heat ray reflecting function is coated on the indoor surface of the window glass. In this case, the coating layer may have an opening in order to suppress a decrease in radio wave transmission performance. The opening is preferably located at a position facing at least a part of the radiating element 10 and the waveguide member 20. The opening may be patterned. The patterning means that the coating layer remains in a lattice shape, for example. Only a part of the opening may be patterned.

[0014] Examples of the material for the window glass 201 include soda-lime silica glass, borosilicate glass, aluminosilicate glass, and non-alkali glass.

[0015] The thickness of the window glass 201 is preferably 1.0 to 20 mm. If the thickness of the window glass 201 is 1.0 mm or more, it has sufficient strength for mounting an antenna unit. If the thickness of the window glass 201 is 20 mm or less, it has good radio wave transmission performance. The thickness of the window glass 201 is more preferably 3.0 to 15 mm, and further preferably 9.0 to 13 mm.

[0016] The antenna unit 101 is a device that is attached to the indoor side of a window glass 201 for a building and used to transmit and receive electromagnetic waves through the window glass 201. The antenna unit 101 is formed to be capable of transmitting and receiving radio waves corresponding to wireless communication standards such as the fifth generation mobile communication system (so-called 5G) and Bluetooth (registered trademark), and wireless LAN (Local Area Network) standards such as IEEE802.11ac. The antenna unit 101 may be formed to be capable of transmitting and receiving electromagnetic waves corresponding to standards other than these, or may be formed to be capable of transmitting and receiving electromagnetic waves of a plurality of different frequencies. The antenna unit 101 can be used, for example, as a wireless base station used facing the window glass 201.

[0017] In the embodiment shown in FIG. 2, the antenna unit 101 comprises a radiating element 10, a phase control member 80 and a conductor 30.

[0018] The radiating element 10 is an antenna conductor formed to be capable of transmitting and receiving radio waves in a desired frequency band. Examples of the desired frequency band include the UHF (Ultra High Frequency) band with a frequency of 0.3 to 3 GHz, the SHF (Super High Frequency) band with a frequency of 3 to 30 GHz, and the EHF (Extremely High Frequency) band with a frequency of 30 to 300 GHz. The radiating element 10 functions as a radiator. The radiating element 10 may be a single antenna element, or may include multiple antenna elements with different feeding points.

[0019] The phase control member 80 is provided so as to be located on the outdoor side with respect to the radiating element 10, and in the illustrated embodiment, is provided so as to be located in a specific direction (more specifically, on the negative side in the Y-axis direction) with respect to the radiating element 10. The phase control member 80 in this embodiment is provided so as to be located between the window glass 201 and the radiating element 10, and has a waveguide member 20 that controls the phase of the radio waves to guide the radio waves radiated from the radiating element 10 in a specific direction (in the illustrated case, the negative side in the Y-axis direction). The phase control member 80 can arbitrarily form the directivity of the antenna unit 101.

[0020] The phase control member 80 includes a dielectric member 41 and a waveguide member 20. The waveguide member 20 includes a plurality of conductor portions. Four conductor portions 21 to 24 are illustrated in FIG. 8 (details will be described later).

[0021] The conductor 30 is provided so as to be located on the indoor side with respect to the radiating element 10, and in the embodiment of FIG. 2, is provided so as to be located on the positive side in the Y-axis direction with respect to the radiating element 10.

[0022] In this way, the antenna unit 101 includes a phase control member 80 that controls the phase of the radio wave radiated from the radiating element 10. The phase control member 80 has a plurality of conductor parts in the waveguide member 20, and thus can control the phase of the radio wave radiated from the radiating element 10, thereby changing the radiation direction of the radio wave. Since the radiation direction of the radio wave radiated from the radiating element 10 can be changed, the gain difference between the main lobe and the grating lobe of the antenna unit 101 (hereinafter also simply referred to as the gain difference) can be increased.

[0023] In addition, the distance between the radiating element 10 and the waveguide member 20 is a, and the relative dielectric constant of the medium made of the dielectric member 41 between the radiating element 10 and the waveguide member 20 is ε r Then, a is (2.11×ε r In terms of increasing the gain difference, it is preferable that the distance a is equal to or greater than -1.82) mm. The present inventor has found that by setting the distance a in this way, the gain difference is equal to or greater than 0 dB. A gain difference of 0 dB or greater means that the gain of the main lobe is equal to or greater than the gain of the grating lobe. There is no particular upper limit to a, but a may be equal to or less than 100 mm, equal to or less than 50 mm, equal to or less than 30 mm, equal to or less than 20 mm, or equal to or less than 10 mm. In addition, when the wavelength at the operating frequency of the radiating element 10 is λg, a may be equal to or less than 100×λg / 85.7, equal to or less than 50×λg / 85.7, equal to or less than 30×λg / 85.7, equal to or less than 20×λg / 85.7, or equal to or less than 10×λg / 85.7.

[0024] When the operating frequency of the radiating element 10 is 0.7 to 30 GHz (preferably 1.5 to 6.0 GHz, more preferably 2.5 to 4.5 GHz, further preferably 3.3 to 3.7 GHz, and particularly preferably 3.5 GHz), a is given by (2.11×ε r It is particularly preferable that the difference be −1.82 mm or more in order to increase the gain difference.

[0025] Moreover, the value obtained by dividing the total area S of the plurality of conductors (waveguide members 20) by the area of ​​the windowpane 201 is preferably 0.00001 to 0.001. If the value obtained by dividing the total area S of the waveguide members 20 by the area of ​​the windowpane 201 is 0.00001 or more, the gain difference is large. The value obtained by dividing the total area S of the waveguide members 20 by the area of ​​the windowpane 201 is more preferably 0.00005 or more, further preferably 0.0001 or more, and particularly preferably 0.0005 or more. If the value obtained by dividing the total area S of the waveguide members 20 by the area of ​​the windowpane 201 is 0.001 or less, the waveguide members 20 are less noticeable in appearance, and the design is good. The value obtained by dividing the total area S of the waveguide members 20 by the area of ​​the windowpane 201 is more preferably 0.0008 or less, and further preferably 0.0007 or less.

[0026] Moreover, if the gain difference is 3 dB or more, even if there is an obstacle such as a window glass facing the antenna unit, the reflection of the radio wave from the obstacle is suppressed to a large extent, so this is preferable. The gain difference is more preferably 4 dB or more, and even more preferably 5 dB or more.

[0027] Next, the embodiment shown in FIG. 2 will be described in more detail.

[0028] The antenna unit 101 includes a radiating element 10, a substrate 50, a conductor 30, a phase control member 80, and a supporting portion 60. The phase control member 80 includes a waveguide member 20 and a dielectric member 41.

[0029] The radiating element 10 is provided on a first main surface on the outdoor side of the base material 50. The radiating element 10 may be formed by printing a metal material so as to overlap at least a portion of the ceramic layer provided on the first main surface of the base material 50. In this way, the radiating element 10 is provided on the first main surface of the base material 50, straddling the portion where the ceramic layer is formed and the other portion.

[0030] The radiating element 10 is, for example, a conductor formed in a planar shape. The metal material forming the radiating element 10 may be a conductive material such as gold, silver, copper, aluminum, chromium, lead, zinc, nickel, or platinum. The conductive material may be an alloy, for example, an alloy of copper and zinc (brass), an alloy of silver and copper, or an alloy of silver and aluminum. The radiating element 10 may be a thin film. The shape of the radiating element 10 may be rectangular or circular, but is not limited to these shapes. For example, at least one radiating element 10 is provided so as to be located between the waveguide member 20 and the conductor 30, and in the illustrated embodiment, the radiating element 10 is formed on the surface of the substrate 50 located between the waveguide member 20 and the conductor 30 on the side of the waveguide member 20. The radiating element 10 is fed, for example, by a feeding point with the conductor 30 as the ground reference. For example, a patch element (patch antenna) or a dipole element (dipole antenna) may be used as the radiating element 10.

[0031] Alternative materials for forming the radiating element 10 include Fluorine-Doped Tin Oxide (FTO) and Indium Tin Oxide (ITO).

[0032] The ceramic layer described above can be formed on the first main surface of the base material 50 by printing or the like. By providing the ceramic layer, the wiring (not shown) attached to the radiating element 10 can be covered and concealed, resulting in good design. In this embodiment, the ceramic layer does not have to be provided on the first main surface, and may be provided on the second main surface of the base material 50 on the indoor side. Providing the ceramic layer on the first main surface of the base material 50 is preferable, since the radiating element 10 and the ceramic layer can be provided on the base material 50 by printing in the same process.

[0033] The material of the ceramic layer is glass frit or the like, and the thickness thereof is preferably 1 to 20 μm.

[0034] In this embodiment, the radiating element 10 is provided on the first main surface of the base material 50, but may be provided inside the base material 50. In this case, the radiating element 10 can be provided inside the base material 50 in the form of, for example, a coil.

[0035] When the substrate 50 is a laminated glass including a pair of glass plates and a resin layer provided between the pair of glass plates, the radiating element 10 may be provided between the glass plates and the resin layer that constitute the laminated glass.

[0036] Moreover, the radiating element 10 itself may be formed in a flat plate shape. In this case, the base material 50 is not used, and the flat plate-shaped radiating element 10 may be directly attached to the support portion 60.

[0037] The radiating element 10 may be provided inside the container other than on the base material 50. In this case, the radiating element 10 may be, for example, a flat plate-shaped radiating element 10 provided inside the container. The shape of the container is not particularly limited and may be rectangular. The base material 50 may be a part of the container.

[0038] The radiating element 10 is preferably optically transparent. If the radiating element 10 is optically transparent, it has good design and can reduce the average solar absorptance. The visible light transmittance of the radiating element 10 is preferably 40% or more, and 60% or more is preferable in terms of maintaining the function as window glass in terms of transparency. The visible light transmittance can be determined according to JIS R 3106 (1998).

[0039] The radiating element 10 is preferably formed in a mesh shape to have optical transparency. Note that the mesh shape refers to a state in which the plane of the radiating element 10 has a network of through holes.

[0040] When the radiating element 10 is formed in a mesh shape, the mesh may have a square or diamond shape. The line width of the mesh is preferably 5 to 30 μm, and more preferably 6 to 15 μm. The line spacing of the mesh is preferably 50 to 500 μm, and more preferably 100 to 300 μm.

[0041] The aperture ratio of the radiating element 10 is preferably 80% or more, and more preferably 90% or more. The aperture ratio of the radiating element 10 is the ratio of the area of ​​the openings to the total area of ​​the radiating element 10 including the openings formed in the radiating element 10. The larger the aperture ratio of the radiating element 10, the higher the visible light transmittance of the radiating element 10 can be.

[0042] The thickness of the radiating element 10 is preferably 400 nm or less, more preferably 300 nm or less. The lower limit of the thickness of the radiating element 10 is not particularly limited, but may be 2 nm or more, 10 nm or more, or 30 nm or more.

[0043] Furthermore, when the radiating element 10 is formed in a mesh shape, the thickness of the radiating element 10 may be 2 to 40 μm. By forming the radiating element 10 in a mesh shape, it is possible to increase the visible light transmittance even if the radiating element 10 is thick.

[0044] The substrate 50 is, for example, a substrate disposed parallel to the window glass 201. The substrate 50 is, for example, rectangular in plan view, and has a first main surface and a second main surface. The first main surface of the substrate 50 is disposed so as to face the outdoor side, and in the embodiment shown in FIG. 2, it is disposed so as to face the second glass surface on the indoor side of the window glass 201. The second main surface of the substrate 50 is disposed so as to face the indoor side, and in the embodiment shown in FIG. 2, it is disposed so as to face the same direction as the second glass surface on the indoor side of the window glass 201.

[0045] The base material 50 may be provided at a predetermined angle with respect to the window glass 201. The antenna unit 101 may radiate electromagnetic waves in a state in which the base material 50 (normal direction) on which the radiating element 10 is provided is inclined with respect to the window glass 201 (normal direction). For example, the antenna unit 101 may be installed at a location above the ground surface, such as a window glass of a building, and radiate electromagnetic waves toward the ground surface to form an area on the ground surface. The inclination angle between the base material 50 and the window glass 201 may be 0 degrees or more, 5 degrees or more, or 10 degrees or more in terms of improving the transmission direction of radio waves. In addition, the inclination angle between the base material 50 and the window glass 201 may be 50 degrees or less, 30 degrees or less, or 20 degrees or less in order to transmit radio waves to the outdoors.

[0046] The material forming the base material 50 is designed according to the antenna performance such as power and directivity required for the radiating element 10, and may be, for example, a dielectric material such as glass or resin, a metal, or a composite of these. The base material 50 may be formed from a dielectric material such as resin so as to have optical transparency. By forming the base material 50 from a material having optical transparency, it is possible to reduce the obstruction of the view seen through the window glass 201 by the base material 50.

[0047] When glass is used as the substrate 50, examples of the glass material include soda lime silica glass, borosilicate glass, aluminosilicate glass, and non-alkali glass.

[0048] The glass plate used as the substrate 50 can be manufactured by a known manufacturing method such as a float method, a fusion method, a redraw method, a press molding method, or a pulling method. As a manufacturing method for the glass plate, it is preferable to use the float method because of its excellent productivity and cost.

[0049] The glass plate is formed into a rectangular shape in a plan view. Examples of a method for cutting the glass plate include a method for cutting the glass plate by irradiating a surface of the glass plate with a laser beam and moving an irradiated area of ​​the laser beam on the surface of the glass plate, and a method for mechanically cutting the glass plate using a cutter wheel or the like.

[0050] In this embodiment, the rectangular shape includes not only a rectangular shape and a square shape, but also a rectangular shape and a square shape with rounded corners. The shape of the glass plate in a plan view is not limited to a rectangular shape, and may be a circular shape, etc. In addition, the glass plate is not limited to a single plate, and may be a laminated glass or a double-insulated glass.

[0051] When a resin is used as the substrate 50, the resin is preferably a transparent resin, and examples of the resin include liquid crystal polymer (LCP), polyimide (PI), polyphenylene ether (PPE), polycarbonate, acrylic resin, and fluororesin. Fluororesin is preferable because of its low dielectric constant.

[0052] Examples of fluororesins include ethylene-tetrafluoroethylene copolymers (hereinafter also referred to as "ETFE"), hexafluoropropylene-tetrafluoroethylene copolymers (hereinafter also referred to as "FEP"), tetrafluoroethylene-propylene copolymers, tetrafluoroethylene-hexafluoropropylene-propylene copolymers, perfluoro(alkyl vinyl ether)-tetrafluoroethylene copolymers (hereinafter also referred to as "PFA"), tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymers (hereinafter also referred to as "THV"), polyvinylidene fluoride (hereinafter also referred to as "PVDF"), vinylidene fluoride-hexafluoropropylene copolymers, polyvinyl fluoride, chlorotrifluoroethylene polymers, ethylene-chlorotrifluoroethylene copolymers (hereinafter also referred to as "ECTFE"), polytetrafluoroethylene, etc. Any one of these may be used alone, or two or more may be used in combination.

[0053] The fluororesin is preferably at least one selected from the group consisting of ETFE, FEP, PFA, PVDF, ECTFE and THV, and ETFE is particularly preferred because of its excellent transparency, processability and weather resistance.

[0054] Moreover, Aflex (registered trademark) may be used as the fluororesin.

[0055] The thickness d of the base material 50 is preferably 25 μm to 10 mm. The thickness d of the base material 50 can be arbitrarily designed depending on the location where the radiating element 10 is disposed. Let d be the thickness of the base material 50 (or the distance between the radiating element 10 and the conductor 30), and λ be the wavelength at the operating frequency of the radiating element 10. g Then, d is λ g If the ratio is 1 / 4 or less, this is preferable in terms of increasing the gain difference.

[0056] When the substrate 50 is made of a resin, it is preferable to use a resin formed into a film or sheet. The thickness of the film or sheet is preferably 25 to 1000 μm, more preferably 100 to 800 μm, and particularly preferably 100 to 500 μm, from the viewpoint of excellent antenna holding strength.

[0057] When the base material 50 is made of glass, the thickness of the base material 50 is preferably 1.0 to 10 mm in terms of the strength for holding the antenna.

[0058] The arithmetic mean roughness Ra of the first main surface on the outdoor side of the substrate 50 is preferably 1.2 μm or less. This is because if the arithmetic mean roughness Ra of the first main surface is 1.2 μm or less, air can easily flow in the space formed between the substrate 50 and the window glass 201. The arithmetic mean roughness Ra of the first main surface is more preferably 0.6 μm or less, and further preferably 0.3 μm or less. The lower limit of the arithmetic mean roughness Ra is not particularly limited, but is, for example, 0.001 μm or more.

[0059] The arithmetic mean roughness Ra can be measured based on the Japanese Industrial Standard JIS B0601:2001.

[0060] The area of ​​the substrate 50 is 0.01 to 4 m 2 It is preferable that the area of ​​the substrate 50 is 0.01 m 2 If the length is more than 4 m, it is easy to form the radiating element 10, the conductor 30, etc. 2 If the area of ​​the base material 50 is 0.05 to 2 m2 or less, the antenna unit is less noticeable in appearance and has a good design. 2 is more preferred.

[0061] The antenna unit 101 may have a conductor 30 provided on the second main surface of the base material 50 opposite to the window glass 201 side. The conductor 30 is provided on the indoor side of the radiating element 10, but the conductor 30 itself may not be required. The conductor 30 may be a portion that functions as an electromagnetic shielding layer capable of reducing electromagnetic interference between the electromagnetic waves radiated from the radiating element 10 and the electromagnetic waves generated from electronic devices in the room. The conductor 30 may be a single layer or multiple layers. A known material may be used as the conductor 30, and for example, a metal film such as copper or tungsten, or a transparent substrate using a transparent conductive film may be used.

[0062] As the transparent conductive film, for example, a conductive material having light transmitting properties, such as indium tin oxide (ITO), fluorine-doped tin oxide (FTO), indium zinc oxide (IZO), indium tin oxide doped with silicon oxide (ITSO), zinc oxide (ZnO), or a Si compound containing P or B, can be used.

[0063] The conductor 30 is, for example, a conductor plane formed in a planar shape. The shape of the conductor 30 may be, but is not limited to, a rectangular shape or a circular shape. For example, at least one conductor 30 is provided on the side opposite to the side where the waveguide member 20 is located with respect to the radiating element 10, and in the illustrated embodiment, the conductor 30 is formed on the surface of the substrate 50 opposite to the surface on the waveguide member 20 side.

[0064] The conductor 30 is preferably formed in a mesh shape so as to have optical transparency. Here, the term "mesh" refers to a state in which the plane of the conductor 30 has a network of through holes. When the conductor 30 is formed in a mesh shape, the openings of the mesh may be square or rhombic. The line width of the mesh is preferably 5 to 30 μm, more preferably 6 to 15 μm. The line spacing of the mesh is preferably 50 to 500 μm, more preferably 100 to 300 μm.

[0065] The conductor 30 can be formed by a known method, such as a sputtering method or a vapor deposition method.

[0066] The surface resistivity of the conductor 30 is preferably 20Ω / □ or less, more preferably 10Ω / □ or less, and further preferably 5Ω / □ or less. The size of the conductor 30 is preferably equal to or greater than the size of the substrate 50. By providing the conductor 30 on the second main surface side of the substrate 50 facing indoors, the transmission of radio waves indoors can be suppressed. The surface resistivity of the conductor 30 depends on the thickness, material, and aperture ratio of the conductor 30. The aperture ratio is the ratio of the area of ​​the openings formed in the conductor 30 to the total area of ​​the conductor 30 including the openings.

[0067] The visible light transmittance of the conductor 30 is preferably 40% or more, more preferably 60% or more, from the viewpoint of improving the design. Also, the visible light transmittance of the conductor 30 is preferably 90% or less, more preferably 80% or less, in order to suppress the transmission of radio waves indoors.

[0068] Moreover, the visible light transmittance increases as the aperture ratio of the conductor 30 increases. The aperture ratio of the conductor 30 is preferably 80% or more, and more preferably 90% or more. Moreover, the aperture ratio of the conductor 30 is preferably 95% or less in order to suppress the transmission of radio waves indoors.

[0069] The thickness of the conductor 30 is preferably 400 nm or less, and more preferably 300 nm or less. The lower limit of the thickness of the conductor 30 is not particularly limited, but may be 2 nm or more, 10 nm or more, or 30 nm or more.

[0070] Furthermore, when the conductor 30 is formed in a mesh shape, the thickness of the conductor 30 may be 2 to 40 μm. By forming the conductor 30 in a mesh shape, the visible light transmittance can be increased even if the conductor 30 is thick.

[0071] The antenna unit 101 in this embodiment may have a configuration in which a base material 50 is sandwiched between the radiating element 10 and the conductor 30 so as to form a microstrip antenna, which is a type of planar antenna. Also, a plurality of radiating elements 10 may be arranged on the surface of the base material 50 on the waveguide member 20 side so as to form an array antenna.

[0072] The waveguide member 20 is, for example, a conductor formed in a planar shape. The metal material forming the waveguide member 20 may be a conductive material such as gold, silver, copper, aluminum, chromium, lead, zinc, nickel, or platinum. The conductive material may be an alloy, for example, an alloy of copper and zinc (brass), an alloy of silver and copper, or an alloy of silver and aluminum. The conductive material may be an alloy, for example, an alloy of copper and zinc (brass), an alloy of silver and copper, or an alloy of silver and aluminum. The waveguide member 20 may be formed by adhering a conductive material to, for example, a glass substrate or a resin substrate. The waveguide member 20 may be a thin film.

[0073] The plurality of conductors used in the waveguide member 20 may be linear or strip-shaped conductor elements, and may be straight or curved. The plurality of conductors may be rectangular or circular.

[0074] The plurality of conductors used in the waveguide 20 may be formed in a mesh shape to have optical transparency. Here, the term "mesh" refers to a state in which the plane of the conductor has a network of through holes. The visible light transmittance of the plurality of conductors used in the waveguide 20 is preferably 40% or more, and more preferably 60% or more, so that the function as a window glass can be maintained in terms of transparency.

[0075] When the conductor is formed in a mesh shape, the mesh may have a rectangular or rhombic shape. When the mesh has a rectangular shape, the mesh preferably has a square shape. If the mesh has a square shape, the design is good. The mesh may have a random shape by a self-organization method. The random shape can prevent moire. The mesh line width is preferably 5 to 30 μm, more preferably 6 to 15 μm. The mesh line spacing is preferably 50 to 500 μm, more preferably 100 to 300 μm. The mesh line spacing is preferably 0.5 λ or less, more preferably 0.1 λ or less, and even more preferably 0.01 λ or less, where λ is the wavelength at the operating frequency of the radiating element 10. If the mesh line spacing is 0.5 λ or less, the antenna has high performance. The mesh line spacing may be 0.001 λ or more.

[0076] The dielectric member 41 is a medium between the radiating element 10 and the waveguide member 20. In this embodiment, the waveguide member 20 is provided on the dielectric member 41, and more specifically, is formed on the surface of the dielectric member 41 on the outdoor side. The dielectric member 41 is supported by the base material 50 so that the surface of the dielectric member 41 on the indoor side is in contact with the radiating element 10. The dielectric member 41 is, for example, a dielectric base material mainly composed of a dielectric material having a relative dielectric constant greater than 1 and not more than 15 (preferably not more than 7, more preferably not more than 5, and particularly preferably not more than 2.2). For example, fluororesin, COC (cycloolefin copolymer), COP (cycloolefin polymer), PET (polyethylene terephthalate), polyimide, ceramics, sapphire, or a glass substrate can be used as the dielectric member 41. When the dielectric member 41 is formed of a glass substrate, examples of the material of the glass substrate include non-alkali glass, quartz glass, soda lime glass, borosilicate glass, alkali borosilicate glass, and aluminosilicate glass. The relative dielectric constant is measured, for example, by using a cavity resonator.

[0077] The dielectric member 41 has optical transparency that allows visible light to pass therethrough, so that blocking of the view through the window glass 201 by the dielectric member 41 can be reduced.

[0078] The support portion 60 is a portion that supports the antenna unit 101 relative to the window glass 201. In this embodiment, the support portion 60 supports the antenna unit 101 so that a space is formed between the window glass 201 and the waveguide member 20. The support portion 60 may be a spacer that ensures a space between the window glass 201 and the base material 50, or may be a housing for the antenna unit 101. The support portion 60 is formed of a dielectric base material. As a material for the support portion 60, for example, a known resin such as a silicone-based resin, a polysulfide-based resin, or an acrylic-based resin may be used. A metal such as aluminum may also be used.

[0079] The distance D between the window glass 201 and the radiating element 10 is preferably 0 to 3λ, where λ is the wavelength at the resonant frequency of the radiating element 10. If the distance D between the window glass 201 and the radiating element 10 is 0 to 3λ, the reflection of radio waves at the glass interface can be reduced. The distance D between the window glass 201 and the radiating element 10 is more preferably 0.1λ or more, and even more preferably 0.2λ or more. The distance D between the window glass 201 and the radiating element 10 is more preferably 2λ or less, even more preferably λ or less, and particularly preferably 0.6λ or less.

[0080] Moreover, the value obtained by dividing the total area S of the plurality of conductors (waveguide member 20) by the area of ​​the substrate 50 is preferably 0.0001 to 0.01. If the value obtained by dividing the total area S of the waveguide member 20 by the area of ​​the substrate 50 is 0.0001 or more, the gain difference is large. The value obtained by dividing the total area S of the waveguide member 20 by the area of ​​the substrate 50 is more preferably 0.0005 or more, further preferably 0.001 or more, and particularly preferably 0.0013 or more. If the value obtained by dividing the total area S of the waveguide member 20 by the area of ​​the substrate 50 is 0.01 or less, the waveguide member 20 is less noticeable in appearance, and the design is good. The value obtained by dividing the total area S of the waveguide member 20 by the area of ​​the substrate 50 is more preferably 0.005 or less, and further preferably 0.002 or less.

[0081] The waveguide member 20 may be provided in contact with the indoor surface of the window glass 201. In this case, the dielectric member 41 may be present or absent, and it is preferable that the relative dielectric constant of the medium between the radiating element 10 and the waveguide member 20 is lower than the relative dielectric constant of the window glass 201. The relative dielectric constant of the window glass 201 may be 10 or less, 9 or less, 7 or less, or 5 or less.

[0082] 3 is a cross-sectional view showing a schematic example of a laminated structure of a window glass with an antenna unit according to the second embodiment. Descriptions of the same structures and effects as those of the above-mentioned embodiments will be omitted or simplified by incorporating the above-mentioned descriptions. The window glass with an antenna unit 302 includes an antenna unit 102 and a window glass 201. The antenna unit 102 is attached to the indoor surface of the window glass 201 for a building.

[0083] As in the above-described embodiment, the antenna unit 102 has a phase control member 80 disposed between the window glass 201 and the radiating element 10, and therefore the gain difference is large.

[0084] In the antenna unit 102, the dielectric member 41 is supported by a spacer 61 relative to the substrate 50 so that the indoor surface of the dielectric member 41 does not come into contact with the radiating element 10. In other words, the dielectric member 41 is positioned so that a space 42 is formed between the radiating element 10 and the dielectric member 41, and the medium between the radiating element 10 and the waveguide member 20 includes both the dielectric member 41 and the space 42. Air is present in the space 42, but it may be a gas other than air. The space 42 may be a vacuum. Since the radiating element 10 is not in contact with the dielectric member 41, the resonant frequency is less susceptible to the influence of the dielectric member 41, resulting in a large gain difference.

[0085] Since the antenna unit 102 is positioned such that a space 42 is formed between the dielectric member 41 and the radiating element 10, it is preferable that a is 2.1 mm or more in terms of increasing the gain difference. The distance a is determined by the effective relative dielectric constants of the dielectric member 41 and the space 42. The inventors have found that when the dielectric member 41 is positioned such that a space 42 is formed between the dielectric member 41 and the radiating element 10, by setting the distance a in this way, the gain difference becomes 0 dB or more.

[0086] 4 is a cross-sectional view showing a typical example of a laminated structure of a window glass with an antenna unit according to the third embodiment. Descriptions of the same structures and effects as those of the above-mentioned embodiments will be omitted or simplified by incorporating the above-mentioned descriptions. The window glass with an antenna unit 303 includes an antenna unit 103 and a window glass 201. The antenna unit 103 is attached to the indoor surface of the window glass 201 for a building.

[0087] As in the above-described embodiment, the antenna unit 103 has a large gain difference because the phase control member 81 is disposed between the window glass 201 and the radiating element 10. The phase control member 81 has a waveguide member 20 having a plurality of conductors, and a dielectric member 41 located on the window glass 201 side with respect to the waveguide member 20, and has the same function as the phase control member 80 in the above-described embodiment.

[0088] In the antenna unit 103, the dielectric member 41 is supported by the spacer 61 with respect to the base material 50 so that the waveguide member 20 formed on the indoor surface of the dielectric member 41 does not come into contact with the radiating element 10. That is, the antenna unit 103 includes the dielectric member 41, which is an example of a dielectric located on the opposite side of the waveguide member 20 from the radiating element 10. The waveguide member 20 is located between the dielectric member 41 and the radiating element 10. The waveguide member 20 provided on the indoor surface of the dielectric member 41 is located so that a space 42 is formed between the waveguide member 20 and the radiating element 10, and the medium between the radiating element 10 and the waveguide member 20 includes only the space 42. Air exists in the space 42, but it may be a gas other than air. The space 42 may be a vacuum. Since the radiating element 10 does not come into contact with the dielectric member 41 and the medium between the radiating element 10 and the waveguide member 20 is only the space 42, the resonant frequency is less affected by the dielectric member 41, and the gain difference is large.

[0089] In antenna unit 103, the medium between radiating element 10 and waveguide 20 contains only space 42, so it is preferable for a to be 2.3 mm or more in terms of increasing the gain difference. The inventors have found that when the medium between radiating element 10 and waveguide 20 contains only space 42, by setting distance a in this manner, the gain difference becomes 0 dB or more.

[0090] Although the dielectric member 41 is supported by the spacer 61 with respect to the base material 50, the dielectric member 41 may be supported by the support portion 60. Moreover, the dielectric member 41 does not have to be provided, and there may be only a space between the waveguide member 20 and the window glass 201. When there is only a space between the waveguide member 20 and the window glass 201, the waveguide member 20 is supported by, for example, the support portion 60 or the spacer 61.

[0091] 5 is a cross-sectional view showing a schematic example of a laminated structure of a window glass with an antenna unit according to the fourth embodiment. Descriptions of the same structures and effects as those of the above-mentioned embodiments will be omitted or simplified by incorporating the above description. The window glass with an antenna unit 304 includes an antenna unit 104 and a window glass 201. The antenna unit 104 is attached to the indoor surface of the window glass 201 for a building.

[0092] As in the above-described embodiment, the antenna unit 104 has a large gain difference because the phase control member 82 is disposed between the window glass 201 and the radiating element 10. The phase control member 82 has a waveguide member 20 having a plurality of conductors, and a supporting wall 62 which is a dielectric and is located on the window glass 201 side with respect to the waveguide member 20, and has the same function as the phase control member 80 in the above-described embodiment.

[0093] In the antenna unit 104, the waveguide 20 is formed on the support wall 62 of the support 60 on the window glass 201 side so as not to contact the radiating element 10, and is formed on the inner wall surface of the support wall 62 facing the indoor side. In other words, the antenna unit 104 includes the support 60 (the support wall 62) which is an example of a dielectric material located on the opposite side of the radiating element 10 with respect to the waveguide 20. The waveguide 20 is located between the support wall 62 and the radiating element 10. The waveguide 20 provided on the support wall 62 of the support 60 is located so that a space 42 is formed between the radiating element 10, and the medium between the radiating element 10 and the waveguide 20 includes only the space 42. Air exists in the space 42, but it may be a gas other than air. The space 42 may be a vacuum. Since the medium between the radiating element 10 and the waveguide 20 is only the space 42, the gain difference is large.

[0094] In antenna unit 104, the medium between radiating element 10 and waveguide member 20 contains only space 42, so it is preferable for a to be 2.3 mm or more in order to increase the gain difference.

[0095] 6 is a cross-sectional view showing a schematic example of a laminated structure of a window glass with an antenna unit in the fifth embodiment. Description of the same structures and effects as those of the above-mentioned embodiments will be omitted or simplified by invoking the above description. The window glass with an antenna unit 305 includes an antenna unit 105 and a window glass 201. The antenna unit 105 is attached to the outdoor surface of the window glass 201 for a building.

[0096] Antenna unit 105 has the same layered structure as antenna unit 101 (see FIG. 2). However, antenna unit 105 differs from antenna unit 101 in that radiating element 10 is disposed between window glass 201 and waveguide member 20.

[0097] In this way, the antenna unit 105 has the waveguide member 20 disposed on the opposite side (i.e., the outdoor side) of the window glass 201 located on the indoor side of the radiating element 10. With this arrangement, the phase of the radio waves radiated from the radiating element 10 toward the outdoor side can be controlled by the phase control member 80, and reflection of the radio waves at the interface of the window glass 201 located on the indoor side of the radiating element 10 can be suppressed, resulting in a large gain difference. As a result, the gain of the radio waves incident in the normal direction to the surface of the window glass 201 increases, and reflection to the rear of the radiating element 10 (indoor side) decreases, resulting in a large gain difference. Also, a is given by (2.11×ε r It is preferable that the difference be −1.82 mm or more in order to increase the gain difference.

[0098] The antenna unit attached to the outdoor side of the window glass 201 is not limited to the antenna unit 105 in Fig. 6. For example, an antenna unit having the same layered configuration as the antenna unit 102 in Fig. 3, the antenna unit 103 in Fig. 4, or the antenna unit 104 in Fig. 5 may be attached to the outdoor side of the window glass 201.

[0099] 7 is a cross-sectional view showing a schematic example of a laminated structure of a window glass with an antenna unit according to the sixth embodiment. Descriptions of the same structures and effects as those of the above-mentioned embodiments will be omitted or simplified by incorporating the above-mentioned descriptions. The window glass with an antenna unit 403 includes an antenna unit 503 and a window glass 201. The antenna unit 503 is attached to the indoor surface of the window glass 201 for a building.

[0100] The antenna unit 503 has the same layered structure as the antenna unit 103 (see FIG. 4). The antenna unit 503 is attached to the window glass 201 so that the matching member 70 is sandwiched between the window glass 201 and the waveguide member 20 when in use.

[0101] The matching member 70 is an example of a matching body that matches the impedance difference between the window glass 201 and a medium present between the radiating element 10 and the window glass 201. By matching the impedance difference, the radio waves radiated from the radiating element 10 toward the window glass 201 can be prevented from being reflected at the interface of the window glass 201, and therefore the gain difference becomes large.

[0102] In addition, the relative dielectric constant of the window glass 201 is ε r 1. The relative dielectric constant of the matching member 70 is ε r 2. The relative dielectric constant of the medium between the matching member 70 and the radiating element 10 is ε r 3, then ε r 1 is ε r Greater than 2, ε r 2 is ε r It is preferable that the gain ratio is larger than 3. As a result, the radio wave radiated from the radiating element 10 passes through the medium between the matching member 70 and the radiating element 10, the matching member 70, and the window glass 201 in that order with reduced reflection loss, resulting in a large gain difference.

[0103] The matching member 70 is provided on the window glass 201. In this embodiment, the matching member 70 is provided on the indoor surface of the window glass 201. The antenna unit 503 is attached to the indoor surface of the window glass 201 via the matching member 70.

[0104] The dielectric member 41 is an example of a medium between the matching member 70 and the radiating element 10. In the window glass 403 with an antenna unit, the matching member 70 and the dielectric member 41 are not in contact with each other, but they may be in contact with each other.

[0105] As in the above embodiment, a is (2.11 × ε r It is preferable that the difference be −1.82 mm or more in order to increase the gain difference.

[0106] The antenna unit attached to the indoor side of the window glass 201 via the matching member 70 is not limited to the antenna unit 503 in Fig. 7. For example, an antenna unit having the same layered configuration as the antenna unit 101 in Fig. 2, the antenna unit 102 in Fig. 3, or the antenna unit 104 in Fig. 5 may be attached to the indoor side of the window glass 201 via the matching member 70.

[0107] Furthermore, the window glass with an antenna unit shown in FIG. 7 may have a conductor provided between the matching member 70 and the window glass 201. By providing a conductor between the matching member 70 and the window glass 201, the thickness of the matching member 70 can be reduced. The conductor provided between the matching member 70 and the window glass 201 is, for example, a conductor pattern having a frequency selective surface (FSS) in which a mesh-like or slit-like pattern or the like is formed so as to allow radio waves of a predetermined frequency band to pass through. The conductor provided between the matching member 70 and the window glass 201 may be a metasurface. The conductor between the matching member 70 and the window glass 201 may not be required.

[0108] Fig. 8 is a perspective view showing a specific example of the configuration of the antenna unit in this embodiment. The radiating element 10 is fed by a feeding point 11. In the embodiment shown in Fig. 8, the waveguide member 20 has a plurality of conductors 21 to 24 arranged parallel to each other. The number of conductors is not limited to four. The plurality of conductors are linear or band-like conductor elements, and may be linear or curved.

[0109] In order to increase the gain difference, the shape of each conductor part may be changed, or the positional relationship between the radiating element 10 and each conductor part may be changed. The multiple conductor parts may have the same shape as each other as shown in Fig. 8. Of the multiple conductor parts, a first group of conductor parts (conductor parts 21 and 22 in Fig. 8) and a second group of conductor parts (conductor parts 23 and 24 in Fig. 8) may be arranged symmetrically with respect to the radiating element 10 as shown in Fig. 8. In the embodiment shown in Fig. 8, the multiple conductor parts 21 to 24 are on the same plane (on the ZX plane) and have the same length in the polarization direction (Z-axis direction) of the radiating element 10.

[0110] The conductors do not have to be on the same plane. The phases of the currents induced in the conductors arranged on different planes are different, resulting in a large gain difference.

[0111] Fig. 9 is a plan view showing a specific example of the antenna unit in this embodiment. Fig. 10 is a plan view showing the configuration of a microstrip array antenna in the antenna unit shown in Fig. 9. Fig. 11 is a plan view showing the configuration of a phase control member in the antenna unit shown in Fig. 9. In the antenna unit 1 shown in Fig. 9, a microstrip array antenna 14 (Fig. 10) in which a radiating element 10 is composed of a plurality of patch elements 10A-10D, and a phase control member 80 (Fig. 11) having a plurality of conductors 21-23 provided on a dielectric member 41 are laminated. The laminated structure is the same as that in Fig. 3. A plurality of patch elements 10A-10D arranged in an array on a substrate 50 are fed by a transmission line 12.

[0112] The multiple conductor parts may include conductor parts having different shapes as shown in Fig. 9. The phases of the currents induced in the conductor parts having different shapes are different, resulting in a large gain difference. In the case of Fig. 9, the conductor parts 22 and 23 have the same shape, but the conductor part 21 has a shape different from the conductor parts 22 and 23. Of the multiple conductor parts, the conductor part of the first group (the conductor part 21 in the case of Fig. 9) and the conductor parts of the second group (the conductor parts 22 and 23 in the case of Fig. 9) may be arranged asymmetrically with respect to the radiating element 10 as shown in Fig. 9. The phases of the currents induced in the conductor parts arranged asymmetrically are different, resulting in a large gain difference.

[0113] The multiple conductor parts may include conductor parts having different lengths in the polarization direction (Z-axis direction) of the radiating element 10 as shown in Fig. 9. Due to the difference in length in the polarization direction of the radiating element 10, the phases of the currents induced in the conductor parts having different lengths are different, resulting in a large gain difference. In the case of Fig. 9, the conductor parts 22 and 23 have the same length B, but the length A of the conductor part 21 is different from the length B of the conductor parts 22 and 23.

[0114] If the lengths A and B of the radiating element 10 in the polarization direction are different, the phase of the current induced in the conductor 21 differs from the phase of the current induced in the conductors 22 and 23, resulting in a large gain difference. In order to increase the gain difference, it is preferable that A / B is 1.1 or more and 2.0 or less.

[0115] 9, when multiple conductors 21-23 are located along the outer edge of patch element 10A in a plan view, the gain of microstrip array antenna 14 is improved. Similarly, when multiple conductors are located along the outer edges of each of patch elements 10B-10D in a plan view, the gain of microstrip array antenna 14 is improved. It is more preferable to position the multiple conductors along the outer edge extending in the polarization direction of the radiating element (patch element) in terms of improving the gain of microstrip array antenna 14.

[0116] In FIG. 9, the radiating element 10 includes a plurality of antenna elements (four patch elements 10A-10D in this example) connected to one transmission line 12. A plurality of conductors 21-23 are provided for each of the plurality of antenna elements. In the example shown in FIG. 9, three conductors 21-23 are provided for one patch element 10A, three conductors 21-23 are provided for one patch element 10B, three conductors 21-23 are provided for one patch element 10C, and three conductors 21-23 are provided for one patch element 10D. The number of conductors provided for one antenna element may be one or more, but a plurality of conductors allows greater adjustment of the phase of the radio wave radiated from the radiating element 10. The number of conductors provided for each of the plurality of antenna elements may be the same or different among the plurality of antenna elements. One or more conductors provided for one antenna element are disposed in close proximity to the antenna element.

[0117] As shown in Figs. 9 and 10, the antenna unit may include at least one parasitic element 13 adjacent to at least one of the conductor parts. The parasitic element 13 changes the direction of the main lobe, and the gain difference can be increased. The parasitic element 13 shown in Figs. 9 and 10 is provided on the same plane as the radiating element 10 (patch element 10A) and is arranged along the outer edge of the patch element 10A at a distance that allows coupling with the patch element 10A and the conductor parts 22 and 23. The parasitic element 13 may be arranged adjacent to other patch elements 10B and the like in a similar manner. The arrangement of the parasitic element 13 may overlap at least a part of the conductor parts in a plan view, or may not overlap as shown in Fig. 9. The gain difference can be adjusted by adjusting the position of the parasitic element 13 relative to the radiating element 10.

[0118] Fig. 12 is a diagram showing an example of a result of simulating a gain difference obtained by out-of-phase feeding when A / B=1.0 in the antenna unit shown in Fig. 9. Fig. 13 is a diagram showing an example of a result of simulating a relationship between a gain difference obtained by out-of-phase feeding and A / B in the antenna unit shown in Fig. 9.

[0119] 12 and 13 assume that antenna unit 1 is installed so that patch elements 10A and 10C are on the upper side in the vertical direction and patch elements 10B and 10D are on the lower side in the vertical direction, and patch elements 10A and 10C and patch elements 10B and 10D are fed in opposite phases. The horizontal axis in Fig. 12 represents the inclination angle θ of the main lobe (grating lobe) with respect to the horizontal plane. The main lobe represents the gain radiated downward with respect to the horizontal plane, and the grating lobe represents the gain radiated upward with respect to the horizontal plane.

[0120] In the simulation of Figures 12 and 13, the simulation conditions such as the dimensions of each part shown in Figures 9 and 10 are as follows: A: Variable B:22.5mm (fixed) L1: 212mm L2: 850mm L3: 24.5 mm L4: 55.5 mm L5: 18.2 mm L6: 60.0mm Thickness of base material 50: 3.3 mm Dielectric constant of base material 50: 4.4 Thickness of dielectric member 41: 1.1 mm Dielectric constant of dielectric member 41: 4.4 Distance between the radiating element 10 and the phase control member 80: 7.5 mm Distance between radiating element 10 and window glass 201: 15 mm It was decided.

[0121] As shown in FIG. 13, the larger A / B is, the more the gain difference is improved, and when A / B is 0.9 or more, the degree of improvement in the gain difference is high.

[0122] Fig. 14 is a diagram showing an example of a result of simulating a gain difference obtained by phase difference feeding when A / B=1.0 in the antenna unit shown in Fig. 9. Fig. 15 is a diagram showing an example of a result of simulating a relationship between a gain difference obtained by phase difference feeding and A / B in the antenna unit shown in Fig. 9.

[0123] 14 and 15 assume that antenna unit 1 is installed so that patch elements 10A and 10C are on the upper side in the vertical direction and patch elements 10B and 10D are on the lower side in the vertical direction, and the phase is set so that the main lobe inclination angle θ is 20 degrees (so that the gain at 20 degrees is maximized). The conditions for the simulations of Figures 14 and 15 are the same as those for the simulations of Figures 12 and 13.

[0124] As shown in FIG. 15, the larger A / B is, the more the gain difference improves, and when A / B is 1.1 or more, the gain difference becomes large.

[0125] Fig. 16 is a diagram showing an antenna unit 1 facing a window glass 201 on which glass plates 211, 211 are stacked. Fig. 17 is a diagram showing an example of a simulation result of a gain obtained by phase difference feeding when A / B=1.0 in the case where a phase control member 80 is present in the antenna unit 1 of Fig. 16. Fig. 18 is a diagram showing an example of a simulation result of a gain obtained by phase difference feeding when A / B=1.0 in the case where a phase control member 80 is not present in the antenna unit 1 of Fig. 16.

[0126] Figures 17 and 18 assume that antenna unit 1 is installed as shown in Figure 16, with patch elements 10A and 10C on the upper vertical side and patch elements 10B and 10D on the lower vertical side, and the phase is set so that the inclination angle θ of the main lobe is 20 degrees (so that the gain at 20 degrees is maximized).

[0127] The simulation conditions for Figures 17 and 18 are: Distance between radiating element 10 and window glass 201: 15 mm The thickness of each of the glass plates 211 and 212 is 4.7 mm. Thickness of the air layer 213 between the glass plates 211 and 212: 6.0 mm The remaining conditions are the same as those in the simulations of Figs.

[0128] When the phase control member 80 is present (FIG. 17), the gain is 11.5 dBi when the inclination angle θ is 20 degrees, and when the phase control member 80 is not present (FIG. 18), the gain is 8.1 dBi when the inclination angle θ is 20 degrees. Thus, the results show that the reflection by the window glass 201 is suppressed by providing the phase control member 80.

[0129] Although the antenna unit and the window glass have been described above by way of the embodiment, the present invention is not limited to the above embodiment. Various modifications and improvements, such as combinations with or substitutions for part or all of the other embodiments, are possible within the scope of the present invention.

[0130] For example, the antenna unit does not have to be fixed to the window glass. The antenna unit can be hung from the ceiling or fixed to a protrusion around the window glass (for example, a window frame or window sash that holds the outer edge of the window glass) so that it is installed facing the window glass. The antenna unit can be installed in contact with the window glass, or in close proximity to the window glass without contacting it.

[0131] Furthermore, the number of conductor portions that the phase control member has is not limited to a plurality, and may be one.

[0132] This international application claims priority to Japanese Patent Application No. 2019-169601, filed on September 18, 2019, the entire contents of which are incorporated herein by reference. [Explanation of symbols]

[0133] 1 Antenna Unit 10 Radiating element 11 Power supply point 13 Parasitic element 14 Microstrip Array Antenna 20 Waveguide member 21~24 Conductor section 30 Conductor 41 Dielectric materials 42 Space 50 Base material 60 Support part 62 Supporting wall 70 Alignment member 80, 81, 82 Phase control member 100 Planar Antenna 101~105,503 Antenna unit 200,201 Window glass 301~305,403 Window glass with antenna

Claims

1. An antenna unit that is installed facing a window glass for a building, A radiating element; a phase control member that is located on the outdoor side of the radiating element and controls the phase of radio waves radiated from the radiating element; a conductor located on the indoor side of the radiating element; the phase control member is a member having a dielectric and a plurality of conductor portions, the plurality of conductor portions include conductor portions having different lengths in a polarization direction of the radiating element, When the different lengths are A and B, An antenna unit in which A / B is greater than or equal to 1.1 and less than or equal to 2.

0.

2. The antenna unit according to claim 1 , wherein the plurality of conductor portions are on the same plane.

3. The antenna unit of claim 1 , wherein the plurality of conductor portions are not coplanar.

4. An antenna unit that is installed facing a window glass for a building, A radiating element; a phase control member that is located on the outdoor side of the radiating element and controls the phase of radio waves radiated from the radiating element; a conductor located on the indoor side of the radiating element; the phase control member is a member having a dielectric and a plurality of conductor portions, The antenna unit, wherein the plurality of conductor portions include conductor portions having different shapes and are not on the same plane.

5. 5. The antenna unit according to claim 1, wherein a gain difference between a main lobe and a grating lobe is 3 dB or more.

6. An antenna unit that is installed facing a window glass for a building, A radiating element; a phase control member that is located on the outdoor side of the radiating element and controls the phase of radio waves radiated from the radiating element; a conductor located on the indoor side of the radiating element; the phase control member is a member having a dielectric and a plurality of conductor portions, An antenna unit in which the gain difference between the main lobe and the grating lobe is 3 dB or more.

7. An antenna unit according to claim 1 , wherein the radiating element is a patch element.

8. An antenna unit that is installed facing a window glass for a building, A radiating element; a phase control member that is located on the outdoor side of the radiating element and controls the phase of radio waves radiated from the radiating element; a conductor located on the indoor side of the radiating element; the phase control member is a member having a dielectric and a plurality of conductor portions, the radiating element is a patch element; the plurality of conductors are located along an outer edge of the patch element in a plan view.

9. The antenna unit according to claim 1 , wherein the plurality of conductor portions are linear or strip-shaped conductor elements.

10. The antenna unit according to claim 1 , wherein the plurality of conductors transmit visible light.

11. The antenna unit according to claim 1 , further comprising at least one parasitic element adjacent to at least one of the plurality of conductor sections.

12. The radiating element includes a plurality of antenna elements; The antenna unit according to claim 1 , wherein the plurality of conductor portions are provided for the plurality of antenna elements, respectively.

13. An antenna unit described in any one of claims 1 to 12, wherein the dielectric is a glass substrate.

14. An antenna unit as described in any one of claims 1 to 13, wherein the dielectric is between the radiating element and the multiple conductor portions, and when the relative dielectric constant of the dielectric is εr, the distance between the radiating element and the multiple conductor portions is (2.11 × εr - 1.82) mm or more.

15. A window pane comprising an antenna unit according to any one of the preceding claims.

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