Vehicle antenna device and vehicle

Abstract

This vehicle antenna device is attached to a vehicle body having a first opening provided in a first metal member of a roof part of the vehicle body and a second opening provided in a second metal member of a side part of the vehicle body and adjacent to the first opening. The vehicle antenna device includes: a dielectric substrate provided in the first opening; a conductive film provided on the dielectric substrate; and a feeding element provided on the dielectric substrate, the feeding element having a section extending along an opening edge of the first opening and being electrically connected to the conductive film.

Description

Vehicle Antenna Device and Vehicle

[0001] The present disclosure relates to a vehicle antenna device and a vehicle. This application claims priority based on Japanese Patent Application No. 2024-157123 filed in Japan on September 11, 2024, and incorporates its content herein by reference.

[0002] As an antenna device attached to a vehicle, for example, an antenna device in which various antenna elements are stored in a protruding cover on the roof of the vehicle, so-called shark fin antenna, is known. Also, there are vehicle types that have an opening on the roof of the vehicle and arrange a roof glass in the opening. When arranging a roof glass in the opening, through holes are formed in the roof glass, and power lines, signal lines, etc. to the shark fin antenna are connected to a power source and a signal source inside the vehicle through the through holes. The antenna device is attached to the roof glass by a fixture provided in the through hole. The fixture is fixed to the seat inside the vehicle by screwing through an elastic layer (sealing member) provided on the outer surface of the roof glass outside the vehicle compartment, the inner surface of the vehicle compartment, and inside the through hole (see, for example, Patent Document 1).

[0003] Japanese Patent Publication No. 2010-510954 (A)

[0004] By the way, since the conventional antenna device protrudes outside the roof of the vehicle, it does not look good and may cause damage to the overall design of the vehicle.

[0005] Therefore, an object is to provide a vehicle antenna device with good appearance and a vehicle.

[0006] The vehicle antenna device according to an embodiment of the present disclosure is a vehicle antenna device attached to a vehicle body having a first opening provided in a first metal member of a roof portion of the vehicle body and a second opening provided in a second metal member of a side portion of the vehicle body adjacent to the first opening, the vehicle antenna device including a dielectric substrate provided in the first opening, a conductive film provided on the dielectric substrate, and a feeding element provided on the dielectric substrate, having a section extending along an opening edge of the first opening and electrically connected to the conductive film.

[0007] We can provide a vehicle antenna device and a vehicle with a good appearance.

[0008] This figure shows an example of the configuration of a vehicle 1 with the vehicle antenna device 100 of the embodiment attached. This figure shows an example of the configuration of the vehicle antenna device 100. This figure shows an example of a simulation model of the vehicle antenna device 100SIM including the antenna element 120SIM. This figure shows an example of a simulation model of a comparative vehicle antenna device 50SIM including the antenna element 120SIM. This figure shows an example of the simulation results of the frequency characteristics of the gain of the antenna element 120SIM when radio waves are emitted from the antenna element 120SIM. This figure shows the electric field distribution of radio waves emitted from the antenna element 120SIM in the comparative simulation model (see Figure 3B). This figure shows the electric field distribution of radio waves emitted from the antenna element 120SIM in the simulation model of the embodiment (see Figure 3A). This figure shows an example of a specific planar configuration of the vehicle antenna device 100. This figure shows an example of the frequency characteristics of the open-circuit voltage (dBμVemf) measured at the feed point 121AM, obtained by capacitive coupling of the feed element 120AM with the signal received by the conductive film 115. This figure shows an example of a simulation model including the vehicle antenna device 100 and the vehicle body 10. This figure shows an example of the simulation results of the frequency characteristics of the gain of the feed element 120FM when the length La in the Y direction of the feed element 120FM is changed. This figure shows an example of the simulation results of the frequency characteristics of the gain of the feed element 120FM when the length La in the Y direction of the feed element 120FM is changed. This figure shows an example of the simulation results of the frequency characteristics of the gain of the feed element 120DAB when the length La in the Y direction of the feed element 120DAB is changed. This figure shows an example of the simulation results of the frequency characteristics of the gain of the feed element 120DAB when the length La in the Y direction of the feed element 120DAB is changed. This figure shows an example of the simulation results of the gain characteristics of the vehicle antenna device 100 for FM broadcast waves when the length X0 in the X direction of the aperture 11 is changed. This figure shows an example of the simulation results of the gain characteristics of the vehicle antenna device 100 for FM broadcast waves when the length X0 in the X direction of the aperture 11 is changed.This figure shows an example of the simulation results of the gain characteristics of the vehicle antenna device 100 for DAB broadcast waves when the length X0 of the aperture 11 in the X direction is changed. This figure shows an example of the simulation results of the gain characteristics of the vehicle antenna device 100 for DAB broadcast waves when the length X0 of the aperture 11 in the X direction is changed. This figure shows an example of the simulation results of the gain characteristics of the vehicle antenna device 100 for DAB broadcast waves when the length Y0 of the aperture 11 in the Y direction is changed. This figure shows an example of the simulation results of the gain characteristics of the vehicle antenna device 100 for DAB broadcast waves when the length Y0 of the aperture 11 in the Y direction is changed.

[0009] The vehicle antenna device and embodiments to which the present disclosure applies will be described below. In the following, the same elements will be denoted by the same reference numerals, and redundant descriptions may be omitted.

[0010] The following describes the XYZ coordinate system. The directions parallel to the X-axis (X direction), parallel to the Y-axis (Y direction), and parallel to the Z-axis (Z direction) are mutually orthogonal. Also, for the sake of explanation, the -Z direction may be referred to as the lower side or bottom, and the +Z direction as the upper side or top, but this does not indicate a universal up-and-down relationship. Furthermore, a plan view refers to a view from the XY plane. Also, in the following, the length, width, thickness, etc. of each part may be exaggerated to make the structure easier to understand. Furthermore, the terms parallel, right angle, orthogonal, horizontal, vertical, up and down may be used with a degree of deviation that does not impair the effect of the embodiment.

[0011] Examples of vehicle antenna devices in this embodiment include roof glass mounted on the roof of the vehicle, windshields (front glass) mounted on the front of the vehicle, fixed side windows (including front bench glass and rear quarter glass) mounted on the sides of the vehicle, and rear glass mounted on the rear of the vehicle. Vehicle antenna devices are not limited to these examples. Below, as an example, a configuration in which a vehicle antenna device is used as roof glass will be described.

[0012] Vehicles include, for example, electric vehicles (EVs), plug-in hybrid electric vehicles (PHEVs), hybrid vehicles (HVs), gasoline vehicles, or diesel vehicles. Vehicles may also be electric trains or steam locomotives. A vehicle is an example of a mobile vehicle that transports passengers.

[0013] Furthermore, in the following, "exterior of the vehicle" refers to the exterior of the vehicle (outside the cabin), and "interior of the vehicle" refers to the interior of the vehicle (inside the cabin). Also, in the following, the left and right directions in the direction of travel of the vehicle are used, and these will be referred to as left or right.

[0014] <Embodiment> Figure 1 is a diagram showing an example of the configuration of a vehicle 1 to which the vehicle antenna device 100 of the embodiment is attached.

[0015] Vehicle 1 includes a vehicle body 10 and a vehicle antenna device 100. Vehicle 1 is, for example, an electric vehicle (EV), a plug-in hybrid electric vehicle (PHEV), a hybrid vehicle (HV), a gasoline vehicle, or a diesel vehicle. The vehicle may also be a train or a steam locomotive.

[0016] <Vehicle body 10> The vehicle body 10 has an opening 11 in the roof, openings 12 on the left and right sides, an opening 13F for the windshield (front window), and an opening 13R for the rear window. Opening 11 is an example of a first opening, and opening 12 is an example of a second opening.

[0017] The vehicle body 10 is made of iron, for example, but may be made of aluminum or other metals. The vehicle body 10 may also be made of materials other than metal, but the roof panel on the surface of the roof where the opening 11 is provided, or the internal structure of the roof that surrounds the opening 11, may be made of metal. Furthermore, the vehicle body 10 may have the door panel, door sash, beltline, A-pillar, B-pillar, C-pillar, or the part of the roof located at the upper edge of the side window that surrounds the opening 12 when the door is closed made of metal. In the case of a vehicle body without a door sash, when the door is closed, the opening 12 is the area enclosed by the upper edge of the door, the A-pillar, B-pillar, or C-pillar, and the part of the roof located at the upper edge of the side window.

[0018] The metal structure surrounding the opening 11 is an example of a first metal member. The metal member surrounding the opening 12 when the door is closed is an example of a second metal member.

[0019] <Opening 11> The opening 11 is, for example, an opening for roof glass, but it is not limited to roof glass; it may also be an opening for a dielectric outer panel or the like provided on the roof of the vehicle body 10. The opening 11 is a window frame provided on the roof of the vehicle body 10 and is provided with a flange.

[0020] The roof glass and dielectric outer panels may be movable relative to the opening 11 for opening and closing, or they may be fixedly attached to the opening 11. If they are movable relative to the opening 11 for opening and closing, the roof glass and outer panels should be configured to open and close relative to the opening 11 by a drive mechanism such as a motor or regulator provided on the vehicle body 10. Here, as an example, a configuration in which the vehicle antenna device 100 is a roof glass fixedly attached to the opening 11 will be described.

[0021] <Opening 12> Opening 12 is, for example, an opening for the side windows on the left and right sides. In the vehicle 1 shown in Figure 1, for example, there are three openings 12 on each side. The three openings 12 on the left side of the vehicle 1 shown in Figure 1 are provided for the left front side window, the left rear side window, and the left rear quarter window. The same applies to the right side of the vehicle 1.

[0022] The opening 12 is not limited to the front side glass, the left rear side glass, and the left rear quarter glass, but may also be an opening for the front quarter glass or a dielectric outer panel provided on the left and right sides of the vehicle body 10. The opening 12 is a window frame provided on the left and right sides of the vehicle body 10. These side glass and dielectric outer panels may be movable relative to the opening 12, or they may be fixedly attached to the opening 12.

[0023] <Configuration of Vehicle Antenna Device 100> Figure 2 shows an example of the configuration of the vehicle antenna device 100. Here, the configuration of the vehicle antenna device 100 will be described in general terms using Figure 2. The detailed configuration of the vehicle antenna device 100 will be described later using Figure 6.

[0024] Figure 2 defines and explains the XYZ coordinate system. The directions parallel to the X-axis (X direction), the directions parallel to the Y-axis (Y direction), and the directions parallel to the Z-axis (Z direction) are mutually orthogonal. The +Z direction is the exterior side of the vehicle body 10. The Z-axis extends in the direction of the normal to the laminated glass 110. Hereafter, a plan view refers to viewing an object in the XY plane in the direction of the extension of the Z-axis. For example, the +X direction is the front direction of the vehicle 1, and the +Y direction is the left direction of the vehicle 1.

[0025] Figure 2 shows a flange 11A provided in the opening 11 of the vehicle body 10. The vehicle antenna device 100 includes laminated glass 110 and a power supply element 120, and is provided in the opening 11 of the vehicle body 10, which has an opening 11 for the roof glass and an opening 12 for the side glass. Laminated glass 110 is an example of a dielectric substrate. The vehicle antenna device 100 may also include single-layer glass instead of laminated glass 110, but here, as an example, a configuration including laminated glass 110 will be described.

[0026] Furthermore, the laminated glass 110 comprises glass plates 111 and 112, an interlayer 113, a ceramic layer 114, and a conductive film 115. An example of the conductive film 115 is a heat-reflective film.

[0027] In the vehicle antenna device 100, the feeding element 120 is electrically connected to the conductive film 115 by capacitive coupling with the conductive film 115 via the interlayer 113, glass plate 112, and ceramic layer 114. When the conductive film 115 is fed power via the feeding element 120, the conductive film 115 resonates and transmits and receives radio waves. The feeding element 120 and the conductive film 115 are parallel to the horizontal plane because they are parallel to the XY plane, but they are capable of transmitting and receiving radio waves with vertical polarization in addition to horizontal polarization.

[0028] Here, "electrically connected" means both DC-connected and high-frequency-connected. In the case of DC-connected connections, the conductors are connected by physical contact, allowing both DC and AC currents to flow. In the case of high-frequency-connected connections, the conductors are capacitively coupled with a gap between them, preventing DC current from flowing but allowing AC current (high-frequency current) to flow. The power supply element 120 and the conductive film 115 can be electrically connected in either manner.

[0029] The vehicle antenna device 100 can receive and transmit radio waves using the conductive film 115 via the power supply element 120, with transmission and reception being reverse operations.

[0030] Furthermore, while this description focuses on a configuration in which the conductive film 115 is used as a planar antenna element, for example, the transparent conductive film (indium tin oxide (ITO) film) of a dimming panel may also be used as a planar antenna element.

[0031] The heat-reflective film may have any configuration as long as it can reflect infrared rays. For example, the heat-reflective film may include at least one layer selected from the group consisting of silver (Ag), gold (Au), copper (Cu), aluminum (Al), platinum (Pt), and ion-doped metal oxides.

[0032] In particular, it is preferable to use ion-doped metal oxides. Examples of ion-doped metal oxides include indium tin oxide (ITO), fluorine-doped tin oxide (FTO), aluminum-doped zinc oxide (AZO), and gallium zinc oxide (GZO). As the heat-reflective film, it is preferable to use a laminated film containing a silver-based metal layer and a metal oxide layer in that order from the main surface 111B side.

[0033] A dimmable panel is a panel whose transmittance can be changed in multiple steps. For example, a dimmable panel that can change the transmittance in two steps will turn on when power is supplied, resulting in a high transmittance state, and turn off when the power supply is cut off, resulting in a low transmittance state.

[0034] The dimming panel has a configuration in which a dimming device is sandwiched between two transparent conductive films. Either of the two transparent conductive films can be used as a planar antenna element. As the dimming device, suspended particle devices (SPDs), polymer dispersed liquid crystals (PDLCs), polymer network liquid crystals (PNLCs), guest-host liquid crystals, photochromic, electrochromic, and electrokinetic devices can also be used. The dimming panel may also be a panel whose transmittance changes according to the duty cycle of a PWM (Pulse Width Modulation) pulse signal.

[0035] <Laminated Glass 110> Laminated glass 110 comprises glass plates 111 and 112, an interlayer 113, a ceramic layer 114, and a conductive film 115. Glass plate 111 is an example of a first glass plate, and glass plate 112 is an example of a second glass plate. The ceramic layer 114 is an example of a shielding layer. Laminated glass 110 is fixed to the flange 11A by adhesive 20.

[0036] The laminated glass 110 is formed by bonding a glass plate 111, which is placed on the exterior side of the vehicle body 10 and has a conductive film 115 formed on it, and a glass plate 112, which is placed on the interior side of the vehicle body 10 and has a ceramic layer 114 formed on it, via an interlayer 113 placed between the glass plates 111 and 112.

[0037] <Glass Plates 111 and 112> Glass plates 111 and 112 are transparent, plate-shaped glass plates. Glass plate 111 has an outer main surface 111A and an inner main surface 111B. Main surface 111A is an example of a first main surface, and inner main surface 111B is an example of a second main surface. Glass plate 112 has an outer main surface 112A and an inner main surface 112B. Main surface 112A is an example of a third main surface, and inner main surface 112B is an example of a fourth main surface. Main surfaces 111B and 112B are examples of inner main surfaces.

[0038] Glass plates 111 and 112 may be inorganic glass or organic glass. Examples of inorganic glass include soda-lime glass, aluminosilicate glass, borosilicate glass, alkali-free glass, and quartz glass, which are used without particular limitation. Among these, soda-lime glass is particularly preferred from the viewpoint of manufacturing cost and moldability. The molding method for glass plates 111 and 112 is not particularly limited. For example, in the case of inorganic glass, glass plates molded by the float method are preferred.

[0039] If glass plates 111 and 112 are inorganic glass, glass plates 111 and 112 may be either untempered glass or tempered glass. Untempered glass is made by forming molten glass into a plate and slowly cooling it. Tempered glass is made by forming a compressive stress layer on the surface of untempered glass, and may be either air-cooled tempered glass or chemically tempered glass.

[0040] If the tempered glass is physically tempered glass (for example, air-cooled tempered glass), the glass surface may be strengthened by creating a compressive stress layer on the glass surface due to the temperature difference between the glass surface and the inside of the glass, through operations other than slow cooling, such as rapidly cooling a uniformly heated glass plate from a temperature near its softening point during bending. If the tempered glass is chemically tempered glass, the glass surface may be strengthened after bending by creating compressive stress on the glass surface by methods such as ion exchange. Furthermore, glass plates 111 and 112 may be glass that absorbs ultraviolet or infrared rays. Glass plates 111 and 112 are preferably transparent, but they may be glass plates that are colored to an extent that does not impair transparency. Also, glass plates 111 and 112 do not have to be transparent.

[0041] The laminated glass 110 may have a curved shape such that the exterior side is convex when it is attached to the vehicle body 10. The laminated glass 110 may have a single-bend shape formed by bending in only one direction, or it may have a double-bend shape formed by bending in two directions (for example, the vertical direction when the laminated glass 110 is attached to the vehicle body 10, and the left-right direction perpendicular to the vertical direction). Gravity forming, press forming, or roller forming can be used to form the laminated glass 110. When the laminated glass 110 is formed by bending to a predetermined curvature, the radius of curvature of the laminated glass 110 may be 1,000 mm or more and 100,000 mm or less.

[0042] Further, when the laminated glass 110 is attached to the vehicle body 10, the thickness of the glass plate 111 located on the outdoor side and the thickness of the glass plate 112 located on the indoor side may be the same or different. The thickness of the glass plate 111 is preferably 1.0 mm or more and 3.0 mm or less. When the thickness of the glass plate 111 is 1.mm or more, the strength such as the stone impact resistance performance is sufficient, and when it is 3.0 mm or less, the mass of the laminated glass 110 does not become too large, which is preferable in terms of the fuel consumption of the vehicle. The thickness of the glass plate 112 is preferably 0.3 mm or more and 2.3 mm or less. When the thickness of the glass plate 112 is 0.3 mm or more, the handling property is good, and when it is 2.3 mm or less, the mass does not become too large. If the thicknesses of the glass plates 111 and 112 are each 1.8 mm or less, the weight reduction and sound insulation of the laminated glass 110 can be achieved simultaneously, which is preferable. When the thickness of the glass plate 112 is 1.0 mm or less, the glass plate 112 may be chemically strengthened glass. When the glass plate 112 is chemically strengthened glass, the surface compressive stress value of the glass is preferably 300 MPa or more, and the depth of the compressive stress layer is preferably 2 μm or more.

[0043] When the glass plates 111 and 112 are organic glass, examples of the material of the organic glass include transparent resins such as polycarbonate or acrylic resin (for example, polymethyl methacrylate).

[0044] When a single-layer glass is used instead of the laminated glass 110, the single-layer glass is preferably, for example, strengthened glass. As the strengthened glass, physically strengthened glass (for example, air-cooled strengthened glass) can be used. When it is a single-layer glass, the thickness of the glass plate is preferably 2.0 mm or more and 5.0 mm or less. When the thickness of the glass plate is 2.0 mm or more, the strength such as the stone impact resistance performance is sufficient, and when it is mm or less, the mass of the glass plate does not become too large, which is preferable in terms of the fuel consumption of the vehicle.

[0045] <Interlayer 113> The interlayer 113 is a dielectric material that is transparent or translucent and interposed between the glass plates 111 and 112. The glass plates 111 and 112 are joined by the interlayer 113. Here, as an example, a conductive film 115 is formed on the main surface 111B of the glass plate 111, so more specifically, the interlayer 113 joins the conductive film 115 and the glass plate 112. Also, as an example, the conductive film 115 is not formed on the part of the main surface 111B of the glass plate 111 that is close to the outer edge (outer edge portion), so at the outer edge portion of the glass plate 111, the interlayer 113 joins the glass plates 111 and 112. Examples of materials for the interlayer 113 include thermoplastic polyvinyl butyral (PVB) and ethylene vinyl acetate copolymer (EVA). The interlayer 113 may be transparent or colored. Furthermore, the interlayer film 113 may be composed of two or more layers.

[0046] <Ceramic Layer 114> The ceramic layer 114 is, for example, a fired body of dark-colored ceramic paste, formed by applying a ceramic color paste containing molten glass frit containing black pigment and firing it. The ceramic layer 114 is formed to prevent the adhesive from deteriorating due to ultraviolet rays while the vehicle antenna device 100 is bonded to the vehicle body 10, and to improve the appearance so that the connection part between the vehicle antenna device 100 and the vehicle body 10 is not visible from the outside of the vehicle body 10.

[0047] The ceramic layer 114 is provided, for example, on the main surface 112B on the indoor side of the glass plate 112. Note that the ceramic layer 114 may be provided, for example, on the main surface 111B of the glass plate 111. In this case, specifically, the ceramic layer 114 is provided on the surface of the conductive film 115 on the indoor side (the -Z direction side). That is, the ceramic layer 114 is provided on the main surface 111B of the glass plate 111 via the conductive film 115. Also, in this case, in a portion where the ceramic layer 114 does not exist, the conductive film 115 is provided on the main surface 111B on the indoor side of the glass plate 111. Further, the ceramic layer 114 may be provided one by one on the main surfaces 111B and 112B on the indoor sides of the glass plates 111 and 112, or may be provided only on the main surface 111B on the indoor side of the glass plate 111. Also, the ceramic layer 114 may be provided on the main surface 112A of the glass plate 112 instead of the main surface 111B or 112B. The ceramic layer 114 may be provided only on the main surface 112A of the glass plate 112. Note that when a single-layer glass is used instead of the laminated glass 110, the ceramic layer 114 is provided on the main surface on the indoor side of the single-layer glass.

[0048] The ceramic layer 114 is provided, for example, at the peripheral portion of the laminated glass 110 in plan view of the main surface 112B. The peripheral portion of the laminated glass 110 is a circumferential portion along the outer edge of the laminated glass 110 in plan view, which is slightly inside the outer edge of the laminated glass 110. The peripheral portion of the laminated glass 110 is the peripheral portions of the glass plates 111 and 112, and the outer edge of the laminated glass 110 is the outer edges of the glass plates 111 and 112. If the laminated glass 110 is rectangular in plan view, the ceramic layer 114 is rectangular annular in plan view. For this reason, the ceramic layer 114 has an inner edge 114A. Note that although the ceramic layer 114 extends annularly along the peripheral portion of the laminated glass 110, there may be a portion where it is interrupted.

[0049] <Conductive Film 115> The conductive film 115 is a planar conductor containing a metal or a metal oxide. Examples of conductive films 115 include conductive films for heat ray reflection (heat ray reflective films) and conductive films for low emission (Low-E (Low Emissivity) films). Typical heat ray reflective films are metal films, and examples of metal films include silver (Ag) films. The heat ray reflective film may be a laminate formed by stacking multiple types of films, or it may be a resin film such as polyethylene terephthalate (PET) coated by vapor deposition or the like. Examples of Low-E films include transparent conductive films such as tin oxide, silver, or ITO. The Low-E film may also be a conductive film other than a transparent conductive film such as tin oxide, silver, or ITO.

[0050] This section describes a configuration in which the conductive film 115 is formed on the main surface 111B (second main surface) of the glass plate 111. However, the conductive film 115 may also be formed on main surfaces other than the main surface 111B (second main surface), for example, on the main surface 112A (third main surface) or the main surface 112B (fourth main surface) of the glass plate 112. When single-layer glass is used instead of laminated glass 110, the conductive film 115 is provided on the main surface on the interior side of the single-layer glass.

[0051] Furthermore, the main surface 111B (second main surface) of the glass plate 111 extends along the main surface 112A (third main surface) and the main surface 112B (fourth main surface) of the glass plate 112. Therefore, the formation of the conductive film 115 on the main surface 111B (second main surface) of the glass plate 111 corresponds to the formation of the conductive film 115 along the main surface 112A (third main surface) or the main surface 112B (fourth main surface) of the glass plate 112.

[0052] Furthermore, as described above, the vehicle antenna device 100 utilizes the conductive film 115 as a planar antenna element. The dimensions of the conductive film 115 in the X and Y directions are determined by the frequency of the radio waves received as a planar antenna element. Details of this will be described later.

[0053] <Power supply element 120> The power supply element 120 is formed, for example, on the -Z direction side (indoor side) surface of the ceramic layer 114 formed on the main surface 112B of the glass plate 112 of the laminated glass 110, and extends in the X direction. The power supply element 120 extends in the X direction along the opening edge of the opening 11 of the vehicle body 10. It is preferable that the power supply element 120 is not visible when the vehicle antenna device 100 is viewed from the outside.

[0054] Furthermore, the power supply element 120 is electrically connected to the conductive film 115 by capacitive coupling with the conductive film 115. In Figure 2, since the interlayer 113, glass plate 112, and ceramic layer 114 are present between the conductive film 115 formed on the main surface 111B of the glass plate 111 and the power supply element 120, the power supply element 120 is capacitively coupled to the conductive film 115. In a plan view, the power supply element 120 may or may not overlap with the conductive film 115. Details of the positional relationship between the power supply element 120 and the conductive film 115 in a plan view will be described later using Figure 6.

[0055] As an example, the power supply element 120 extends parallel to the portion of the opening edge of the opening 11 that extends in the X direction and to the portion of the outer edge of the conductive film 115 that extends in the X direction. Figure 2 shows a configuration in which the power supply element 120 extends in the X direction in an XZ cross section, but the power supply element 120 may extend in directions other than the X direction as long as it extends parallel to the opening edge of the opening 11 and to the outer edge of the conductive film 115.

[0056] Furthermore, the power supply element 120 does not need to be strictly parallel to the opening edge of the opening 11 and the outer edge of the conductive film 115, as long as it extends along both sides. The power supply element 120 does not need to be parallel to the opening edge of the opening 11 and the outer edge of the conductive film 115, as long as its function as a power supply element is not impaired.

[0057] Furthermore, at least a portion of the power supply element 120 may be located in a region that does not overlap with the ceramic layer 114 of the laminated glass 110. For example, it is possible to realize a configuration in which at least a portion of the power supply element 120 is located inside the ceramic layer 114 provided at the periphery of the laminated glass 110.

[0058] The feed element 120 is a monopole type feed element. The feed element 120 is powered from a wireless communication device mounted on the vehicle body 10 via a feed cable (omitted in Figure 2). The feed cable is an example of a feed line, and it is preferable that it is positioned so as to overlap with the ceramic layer 114 in a plan view. The signal line of the feed cable is connected to the feed element 120, and the ground line of the feed cable is connected to a metal part of the vehicle body 10. The metal part of the vehicle body 10 is a metal plate with a sufficiently large area relative to the wavelength of the frequency band of the signal being fed, and therefore functions as a ground plane for a monopole antenna. The feed element 120 is a monopole type feed element that utilizes such a ground plane.

[0059] The power supply element 120 can be manufactured, for example, by applying a conductive paste (e.g., silver paste) containing metal powder (e.g., silver powder) and glass frit to the surface of the ceramic layer 114 on the -Z side (indoor side) using a screen printing method, and then firing it. However, the power supply element 120 is not limited to this configuration. For example, it may be manufactured by forming a metal foil such as copper foil on the surface of the ceramic layer 114 on the -Z side (indoor side) and patterning it, or a power supply element 120 made of metal foil such as copper foil on a transparent substrate such as PET may be attached to the surface of the ceramic layer 114 on the -Z side (indoor side).

[0060] Furthermore, regarding the position of the power supply element 120 in the Z direction in the laminated glass 110, the power supply element 120 is not limited to being formed on the -Z direction side (indoor side) surface of the ceramic layer 114 provided on the main surface 112B of the glass plate 112 of the laminated glass 110. The power supply element 120 may be formed on the main surface 112A of the glass plate 112 at a position that overlaps with the ceramic layer 114 in a plan view when the ceramic layer 114 is formed on the -Z direction side (indoor side) surface of the conductive film 115. In this case, the power supply element 120 is capacitively coupled with the conductive film 115 with the ceramic layer 114 and the interlayer 113 present between them.

[0061] Furthermore, the power supply element 120 may be formed on the surface of the conductive film 115 on the -Z side (indoor side) when the ceramic layer 114 is formed on the -Z side (indoor side) of the conductive film 115, at a position where it overlaps with the ceramic layer 114 in a plan view. In this case, the power supply element 120 is capacitively coupled to the conductive film 115 with only the ceramic layer 114 present between it and the conductive film 115. Also, if there is a portion of the indoor surface of the conductive film 115 where the ceramic layer 114 is not formed, the power supply element 120 may be formed on the portion of the indoor surface of the conductive film 115 where the ceramic layer 114 is not formed. In this case, the power supply element 120 is DC-connected to the conductive film 115.

[0062] Furthermore, the power supply element 120 may be provided between the main surface 112A and the ceramic layer 114 when the ceramic layer 114 is provided on the main surface 112A on the outdoor side of the glass plate 112. That is, the power supply element 120 may be formed on the main surface 112A on the outdoor side of the glass plate 112 and covered by the ceramic layer 114. In this case, the power supply element 120 is capacitively coupled with the conductive film 115 with the interlayer 113 and the ceramic layer 114 present between them.

[0063] Furthermore, if the ceramic layer 114 is formed on the main surface 112A of the glass plate 112 of the laminated glass 110, the power supply element 120 only needs to be formed on the portion of the main surface 112B that overlaps with the ceramic layer 114 in a plan view. In this case, the power supply element 120 is capacitively coupled with the conductive film 115 with the interlayer 113, ceramic layer 114, and glass plate 112 present between them.

[0064] Furthermore, if the conductive film 115 is formed on the main surface 112B of the glass plate 112 of the laminated glass 110, and the ceramic layer 114 is formed on the interior-facing surface of the conductive film 115, then the power supply element 120 only needs to be formed on the interior-facing surface of the ceramic layer 114. In this case, the power supply element 120 is capacitively coupled to the conductive film 115 with only the ceramic layer 114 present between it and the conductive film 115. Also, if there is a portion of the interior-facing surface of the conductive film 115 where the ceramic layer 114 is not formed, the power supply element 120 may be formed on the portion of the interior-facing surface of the conductive film 115 where the ceramic layer 114 is not formed. In this case, the power supply element 120 is DC-connected to the conductive film 115.

[0065] Alternatively, instead of connecting the power supply element 120 to the conductive film 115 in a DC manner, the power supply element 120 may be omitted, and the power supply line may be connected to the conductive film 115 in a DC manner. In other words, instead of a configuration in which the power supply element 120 is connected to the conductive film 115 and the power supply line is connected to the power supply element 120, a configuration in which the power supply line is directly connected to the conductive film 115 may be used. In this case, the power supply line only needs to extend along the opening edge of the opening 11 of the vehicle body 10.

[0066] Furthermore, if the vehicle antenna device 100 includes single-layer glass instead of laminated glass 110, and the conductive film 115 is formed on the interior-facing surface of the single-layer glass, the power supply element 120 may be formed on the interior-facing surface of the ceramic layer 114 formed on the interior-facing surface of the conductive film 115. In this case, the power supply element 120 is capacitively coupled to the conductive film 115 with only the ceramic layer 114 present between them. Also, if there is a portion of the interior-facing surface of the conductive film 115 where the ceramic layer 114 is not formed, the power supply element 120 may be formed on the portion of the interior-facing surface of the conductive film 115 where the ceramic layer 114 is not formed. In this case, the power supply element 120 is DC-connected to the conductive film 115.

[0067] As described above, when the power supply element 120 is electrically connected to the conductive film 115, the electrical signal received by the resonating conductive film 115 is sent via the power supply element 120 to a receiver (not shown). Now, let's explain the radio waves that can be received by the resonance of the conductive film 115.

[0068] <Radio waves that can be received by the resonance of the conductive film 115> One example of radio waves that the conductive film 115 can receive is the AM broadcast wave frequency band (522 kHz to 1710 kHz). In addition, radio waves that can be received by the resonance of the conductive film 115 are the FM broadcast wave frequency band (76 MHz to 108 MHz) and DAB (Digital Audio Broadband) Band III (174 MHz to 240 MHz), etc. In addition, one example of radio waves that can be received by the resonance of the conductive film 115 is terrestrial digital television broadcast waves (470 MHz to 710 MHz) and narrowband ITS (Intelligent Transport Systems) radio waves including 760 MHz, etc. Furthermore, a coil may be inserted near the feed point of the antenna device 100 in order to efficiently extract signals from the small area conductive film 115.

[0069] Furthermore, the radio waves that can be received by the resonance of the conductive film 115 may be radio waves in the LTE (Long Term Evolution) frequency band, radio waves in the satellite communication frequency band such as GNSS (Global Navigation Satellite System) and SDARS (Satellite Digital Audio Radio Service), or radio waves in the 5G (Fifth Generation Mobile Communication System) frequency band. The radio waves in the 5G frequency band may be radio waves in the frequency band for narrow-range communication called DSRC (Dedicated Short Range Communication) used in V2X (Vehicle to Everything) such as vehicle-to-vehicle communication and vehicle-to-infrastructure communication (for example, the 5.8 GHz band). In addition, two or more power supply elements 120 may be electrically connected to the conductive film 115 in order to enable reception of two or more of the above-mentioned multiple radio waves.

[0070] One of these multiple frequency bands is an example of a first frequency band, and the feed element 120 for the first frequency band is an example of a first feed element. Another of these multiple frequency bands is an example of a second frequency band, and the feed element 120 for the second frequency band is an example of a second feed element. The vehicle antenna device 100 may be configured to include multiple feed elements 120 for the first frequency band, to include feed elements 120 for both the first and second frequency bands, or to include multiple feed elements 120 for the second frequency band.

[0071] If the system includes multiple feed elements 120 for the first frequency band, there will be multiple feed elements 120 that receive radio waves in the same frequency band (first frequency band). In this case, multiple feed elements 120 that receive radio waves in the same frequency band (first frequency band) may be connected to a single feed point.

[0072] When a feed element 120 that can be used for both the first and second frequency bands is included, one feed element 120 connected to a single feed point can receive radio waves of the first and second frequency bands, which are different from each other. For example, if the wavelength of the broadcast wave is λ and the wavelength shortening factor is k, then radio waves of the first and second frequency bands corresponding to resonances of an odd multiple of k × λ / 4 can be received. The wavelength shortening factor k is, for example, 0.64.

[0073] If the system includes multiple feed elements 120 for the second frequency band, there will be multiple feed elements 120 that receive radio waves in the same frequency band (second frequency band). In this case, multiple feed elements 120 that receive radio waves in the same frequency band (second frequency band) may be connected to a single feed point.

[0074] The vehicle antenna device 100 may include all three configurations: a configuration including a plurality of feed elements 120 for the first frequency band, a configuration including feed elements 120 for the first frequency band and the second frequency band, and a configuration including a plurality of feed elements 120 for the second frequency band. It may also include any two of the three configurations, or any one of the three configurations. Furthermore, if the vehicle antenna device 100 includes a feed element 120 for the first frequency band and a feed element 120 for the second frequency band, the feed element 120 for the first frequency band and the feed element 120 for the second frequency band (two feed elements 120 of different lengths) may be connected to a single feed point.

[0075] <Simulation using the antenna element 120SIM for simulation> Next, a simulation using the antenna element 120SIM for simulation will be explained using Figures 3A to 5B. The antenna element 120SIM, like the feed element 120, is arranged in the XY plane parallel to the horizontal plane, and the simulation model of the vehicle antenna device 100SIM, including the antenna element 120SIM, is capable of receiving horizontally polarized and vertically polarized radio waves.

[0076] <Simulation model of the embodiment and comparison simulation model> Figure 3A shows an example of a simulation model of a vehicle antenna device 100SIM including an antenna element 120SIM. Figure 3B shows an example of a simulation model of a comparison vehicle antenna device 50SIM including an antenna element 120SIM. In Figure 3A, the +X direction is the front direction of the vehicle 1, and the +Y direction is the left direction of the vehicle 1.

[0077] In the simulation model of vehicle 1, which includes the simulation model of the vehicle antenna device 100SIM shown in Figure 3A, the vehicle body 10 is represented as a three-dimensional box-shaped housing. The laminated glass 110 of the vehicle antenna device 100SIM differs from the laminated glass 110 of the vehicle antenna device 100 of the embodiment in that it does not include the conductive film 115. However, since the vehicle antenna device 100SIM is intended to explain the function of the power supply element 120 of the vehicle antenna device 100 of the embodiment, the simulation model of vehicle 1, which includes the simulation model of the vehicle antenna device 100SIM shown in Figure 3A, will be referred to as the simulation model of the embodiment below.

[0078] Furthermore, in the following description, the simulation model including the comparative vehicle antenna device 50SIM and metal plate 51 shown in Figure 3B will be referred to as the comparative simulation model. In both the simulation model of the embodiment and the comparative simulation model, the laminated glass 110 is tempered glass with a thickness of 3.1 mm and is fixed to the opening 11 with a urethane adhesive 20 with a thickness of 5 mm. The laminated glass 110 in both the simulation model of the embodiment and the comparative simulation model does not include the conductive film 115.

[0079] In the simulation model of the embodiment, the vehicle body 10 is made of perfect conductor (PEC) material as an example. The vehicle body 10 has an opening 11 in the roof, openings 12 on the left and right sides, an opening 13F for the windshield, and an opening 13R for the rear window. There are two openings 12 on each side of the vehicle body 10 in the front-to-rear direction, corresponding to the front side windows and rear side windows.

[0080] In Figure 3A, D, which is shown for the aperture 11, is the distance from the center of the width of the aperture 11 in the Y direction to the antenna element 120SIM.

[0081] Furthermore, in Figure 3A, Ws, shown for the left opening 12, is the width of the left opening 12 in the front-to-back direction, and Hs is the height (length in the height direction) of the left opening 12. The same applies to the right opening 12 as well.

[0082] In Figure 3A, Wf, shown in the opening 13F for the windshield, is the width of the opening 13F in the left-right direction, and Hf is the height (length in the height direction) of the opening 13F. Also, Wr, shown in the opening 13R for the rear side glass, is the width of the opening 13R in the left-right direction, and Hr is the height (length in the height direction) of the opening 13R.

[0083] Furthermore, the comparative vehicle antenna device 50SIM shown in Figure 3B, like the vehicle antenna device 100SIM, includes laminated glass 110 and an antenna element 120SIM, but it is not provided on the three-dimensional vehicle body 10, but rather on an opening 52 provided in a flat metal plate 51. The metal plate 51 shown in Figure 3B has the same size as the roof portion of the vehicle body 10 shown in Figure 3A and is made of perfect conductor (PEC). Also, the size of the opening 52 shown in Figure 3B is the same as the size of the opening 11 shown in Figure 3A.

[0084] In Figure 3B, the distance D shown for the aperture 52 is the distance from the center of the width of the aperture 52 in the Y direction to the antenna element 120SIM. The distance D shown in Figure 3B corresponds to the distance D shown in Figure 3A.

[0085] In the simulation model of the embodiment shown in Figure 3A, the antenna element 120SIM is a single linear element, and as an example, it extends in the +X direction parallel to the portion of the opening edge of the rectangular opening 11 that extends in the X direction on the +Y direction side, starting from near the corner on the +Y direction side of the opening edge of the opening 11.

[0086] Similarly, in the comparative simulation model shown in Figure 3B, the antenna element 120SIM is a single linear element, and as an example, it extends in the +X direction parallel to the portion of the rectangular opening edge 52 that extends in the X direction on the +Y direction side, starting from near the +Y direction corner of the opening edge 52 on the -X direction side. Note that the length of the antenna element 120SIM shown in Figures 3A and 3B is the same, and all other conditions are also the same.

[0087] <Simulation Results of Gain Frequency Characteristics> Figure 4 shows an example of the simulation results of the gain frequency characteristics of the antenna element 120SIM when radio waves are radiated from the antenna element 120SIM. Figure 4 shows an example of the calculation results for the antenna element 120SIM in the simulation model of the embodiment (see Figure 3A) and the simulation model for comparison (see Figure 3B).

[0088] Here, using an electromagnetic field simulator, we calculated the frequency characteristics of the gain when horizontally polarized and vertically polarized radio waves are emitted in two simulation models.

[0089] Good gain values ​​were obtained for the horizontally polarized antenna in both the comparative simulation model and the embodiment simulation model. In particular, the gain of the horizontally polarized antenna in the comparative simulation model was approximately -6 dB to approximately -7 dB, which was a better value than the gain of the horizontally polarized antenna in the embodiment simulation model (approximately -13 dB to approximately -14 dB). However, the gain of the horizontally polarized antenna in the embodiment simulation model was also a sufficiently good value.

[0090] Regarding the gain of the vertically polarized antenna, the comparative simulation model showed a low gain of approximately -38 dB to -40 dB, while the simulation model of the embodiment showed a very good value of approximately -3.5 dB to -10 dB. The gain of the vertically polarized antenna in the simulation model of the embodiment was a very good value compared to the gain of the horizontally polarized antenna in the comparative simulation model.

[0091] These differences are thought to arise because the simulation model of the embodiment has the vehicle antenna device 100SIM installed in an opening 11 of the roof of a three-dimensional vehicle body 10, compared to the comparative simulation where the comparative vehicle antenna device 50SIM is installed in an opening 52 of a flat metal plate 51.

[0092] The vehicle antenna device 100SIM has a configuration that includes an antenna element 120SIM arranged in an XY plane parallel to the horizontal plane, and has good vertical polarization antenna gain. Furthermore, because the vehicle antenna device 100SIM includes an antenna element 120SIM arranged in an XY plane parallel to the horizontal plane, it also has good horizontal polarization antenna gain.

[0093] The following discussion examines how a vehicle antenna device 100SIM, which includes an antenna element 120SIM arranged in an XY plane parallel to the horizontal plane, can transmit and receive vertically polarized radio waves.

[0094] <Simulation Results of Electric Field Distribution> Here, we will mainly consider vertically polarized radio waves using a simulation model of an embodiment including a vehicle antenna device 100SIM and a comparative simulation model including a vehicle antenna device 50SIM for comparison.

[0095] <Simulation Results of a Comparative Simulation Model> Figure 5A shows the electric field distribution of radio waves radiated from the antenna element 120SIM of the comparative simulation model (see Figure 3B). The simulation of the electric field distribution was performed in an electromagnetic field simulator, with the frequency of the radio waves radiated by the antenna element 120SIM set to 93 MHz as an example. 93 MHz is a frequency included in the frequency band of FM broadcast waves. In Figure 5A, the direction of the arrows showing the electric field distribution represents the direction of the electric field, and the brightness of the arrows represents the strength of the electric field. The higher the strength of the electric field, the brighter the arrow.

[0096] Figure 5A shows the electric field distribution in the YZ cross-section of a comparative simulation model. The antenna element 120SIM extends parallel to the edge of the aperture 52 that extends in the X direction on the +Y direction side. The position in the X direction of the YZ cross-section shown in Figure 5A is the center of the length of the aperture 52 in the X direction.

[0097] In Figure 5A, among the numerous arrows showing the electric field distribution, the comparative vehicle antenna device 50SIM, the metal plate 51, and the laminated glass 110 extend in the Y direction. Of the three double-headed arrows shown below the numerous arrows, the central double-headed arrow indicates the section in the Y direction where the comparative vehicle antenna device 50SIM exists. The feed point of the antenna element 120SIM is located in the +Y direction portion of the comparative vehicle antenna device 50SIM, and the antenna element 120SIM extends in the X direction at the feed point. The two double-headed arrows at both ends of the three double-headed arrows indicate the section in the Y direction where the metal plate 51 exists.

[0098] In Figure 5A, the electric field distribution is approximately symmetrical above and below the comparative vehicle antenna device 50SIM, and the vertical components of the electric field cancel each other out. Null points are observed to the right and left of the feed point. Because the vertical components are canceled out in this way, it is thought that the gain of the vertically polarized radio waves in the comparative simulation model was low in the simulation results shown in Figure 4.

[0099] <Simulation Results of the Simulation Model of the Embodiment> Figure 5B is a diagram showing the electric field distribution of radio waves radiated from the antenna element 120SIM of the simulation model of the embodiment (see Figure 3A). As an example, the simulation of the electric field distribution was performed with the frequency of the radio waves radiated by the antenna element 120SIM set to 93 MHz. The direction of the arrows showing the electric field distribution represents the direction of the electric field, and the brightness of the arrows represents the strength of the electric field. The higher the strength of the electric field, the brighter the arrow.

[0100] Figure 5B shows the YZ cross-section of the vehicle body 10 within a network of arrows indicating the electric field distribution. Figure 5B shows the vehicle antenna device 100SIM installed in the opening 11 of the roof of the vehicle body 10, and the metal plate portions of the roof on both sides of the opening 11. The central double-headed arrow of the three double-headed arrows shown below the network of arrows indicates the section in the Y direction where the vehicle antenna device 100SIM is located within the opening 11. The feed point is located in the +Y direction portion of the vehicle antenna device 100SIM, and the antenna element 120SIM extends in the X direction at the feed point. The two double-headed arrows at both ends of the three double-headed arrows indicate the sections where the metal plates of the roof are located on both sides of the opening 11.

[0101] The position in the X direction of the YZ cross-section shown in Figure 5B is the center of the length of the opening 11 in the X direction. Since Figure 5B shows the YZ cross-section when viewed from the front to the rear of the vehicle body 10, the +Y direction side is the left side of the vehicle body 10 and the -Y direction side is the right side of the vehicle body 10.

[0102] Furthermore, Figure 5B shows the openings 12 corresponding to the left and right front side windows of the vehicle body 10, on the +Y and -Y directions. The section in the Z direction where the openings 12 are located is indicated by a double-headed arrow to the left of the numerous arrows.

[0103] In Figure 5B, the electric field distribution is asymmetrical above and below the vehicle antenna device 100SIM. In particular, the electric field distribution around the opening 12 located on the +Y direction side (left side) near the feed point differs from the electric field distribution above the vehicle antenna device 100SIM and the roof. Therefore, it is thought that a downward electric field was obtained around the opening 12 located on the +Y direction side (left side) near the feed point.

[0104] From the simulation results shown in Figures 5A and 5B above, it was confirmed that in the simulation model of the embodiment, the vertical component of the electric field is not canceled out because there is an opening 12 for the front side glass on the side of the vehicle body 10 adjacent to the opening 11 in the roof of the vehicle body 10. Therefore, it is possible to receive vertically polarized radio waves with an antenna element 120SIM that is parallel to the XY plane.

[0105] Thus, the opening 12 located on the side of the vehicle body 10 and adjacent to the roof opening 11 contributes to the reception of vertically polarized radio waves. An opening 12 adjacent to an opening 11 means that, among the openings 12 located on the side of the vehicle body 10, it contributes to generating a vertical electric field in the electric field distribution shown in Figure 5B. Therefore, for example, as shown in Figure 3A, if the roof opening 11 is located on the front side of the roof, the opening 12 for the front side glass can be the opening 12 located on the side of the vehicle body 10 and adjacent to the roof opening 11.

[0106] Furthermore, for example, as shown in Figure 3A, if the roof opening 11 is located on the front side of the roof, even if there is no overlapping section between the roof opening 11 and the rear side glass or rear quarter glass opening 12 in the X direction (the longitudinal direction of the vehicle body 10), if it contributes to generating a vertical electric field, it will be considered adjacent to the opening 11. Also, for example, if the roof opening 11 is located at the rear of the roof, even if there is no overlapping section between it and the front side glass or front quarter glass opening 12 in the X direction (the longitudinal direction of the vehicle body 10), if it contributes to generating a vertical electric field, it will be considered adjacent to the opening 11.

[0107] Furthermore, since the antenna element 120SIM can perform a receiving operation in the opposite direction to the transmission operation of radio waves, in the simulation model of the embodiment, vertically polarized radio waves can be received by the antenna element 120SIM parallel to the XY plane.

[0108] The vehicle antenna device 100, whose specific configuration will be explained later with reference to Figure 6, includes a feeding element 120 that extends along the opening edge of the opening 11, similar to the antenna element 120SIM. The feeding element 120 supplies power to the conductive film 115, causing the conductive film 115 to resonate, thereby enabling the transmission and reception of horizontally polarized and vertically polarized radio waves.

[0109] <Specific Configuration of Vehicle Antenna Device 100> Figure 6 is a diagram showing an example of a specific planar configuration of the vehicle antenna device 100. Figure 6 transparently shows the configuration of the vehicle antenna device 100 as seen from the outside of the vehicle interior. In Figure 6, the +X direction is forward, the -X direction is backward, the +Y direction is left, and the -Y direction is right.

[0110] The vehicle antenna device 100 includes laminated glass 110, feed elements 120AM and 120FM, and receiving element 130DTV. The feed elements 120AM and 120FM are specific configurations of the feed element 120 shown in Figure 2 for AM broadcast waves and FM broadcast waves, respectively. The feed elements 120AM and 120FM have the configuration described with reference to Figure 2 regarding the feed element 120.

[0111] The vehicle antenna device 100 is installed in the opening 11 of the vehicle body 10, which has an opening 11 for the roof glass and an opening 12 for the side glass, as shown in Figure 1.

[0112] Here, a vehicle antenna device 100 is described in which, as an example, a configuration including feed elements 120AM and 120FM is included. However, the vehicle antenna device 100 may also be configured to include only one of the feed elements 120AM or 120FM. Furthermore, the vehicle antenna device 100 does not necessarily have to include a receiving element 130DTV.

[0113] The vehicle antenna device 100 shown in Figure 6 includes feed elements 120AM and 120FM that extend along the opening edge of the opening 11, similar to the antenna element 120SIM described above. The opening edge of the opening 11 is located inside the outer edge of the glass plates 111 and 112 and the interlayer 113, and is located on the -Z direction side of the glass plates 111 and 112 and the interlayer 113, and is therefore shown by a dashed line. AM broadcast waves can be received by extracting the signal induced in the conductive film 115 by AM broadcast waves from the feed element 120AM. Furthermore, horizontally polarized and vertically polarized FM broadcast waves can be received by extracting the signal resonated in the conductive film 115 by FM broadcast waves from the feed element 120FM.

[0114] In Figure 6, the laminated glass 110 is shown as consisting of glass plates 111 and 112, an interlayer 113, and a conductive film 115. The outer edges of the glass plates 111 and 112 and the interlayer 113 are shown, and the region where the conductive film 115 exists is indicated by dots. As an example, in Figure 6, the outer edge of the conductive film 115 is located inside the outer edges of the glass plates 111 and 112 and the interlayer 113.

[0115] Furthermore, in Figure 6, only the inner edge 114A of the ceramic layer 114 is shown. The ceramic layer 114 conceals the feed elements 120AM and 120FM and the receiving element 130DTV when the vehicle antenna device 100 is viewed from the outside of the vehicle interior. Therefore, the inner edge 114A is located inside the feed elements 120AM and 120FM and the receiving element 130DTV, while the outer edge of the ceramic layer 114 is located outside the feed elements 120AM and 120FM and the receiving element 130DTV. Note that the position of the outer edge of the ceramic layer 114 may be the same as the position of the outer edge of the glass plates 111 and 112 and the interlayer 113, or it may be located inside the position of the outer edge of the glass plates 111 and 112 and the interlayer 113. Furthermore, the inner edge 114A or outer edge of the ceramic layer 114 may be positioned such that at least a portion of either the power supply elements 120AM and 120FM or the receiving element 130DTV is located in a region that does not overlap with the ceramic layer 114.

[0116] <Reception of AM and FM broadcast waves> The feed elements 120AM and 120FM are shown in Figure 2, illustrating the configuration of the feed element 120 according to an example of a specific application. The feed elements 120AM and 120FM are electrically connected to the conductive film 115. The feed element 120AM extracts the AM broadcast wave (radio wave) received by the conductive film 115 from the conductive film 115, and the feed element 120FM extracts the FM broadcast wave (radio wave) received by the conductive film 115 from the conductive film 115.

[0117] The conductive film 115 can be configured as follows to enable reception of both AM and FM broadcast waves. The wavelength of AM broadcast waves (522 kHz to 1710 kHz) is very long compared to the size of the vehicle antenna device 100 installed in the opening 11 of the vehicle body 10. For this reason, it is preferable to increase the area of ​​the conductive film 115 to lower the output impedance for AM broadcast waves. From this viewpoint, as an example, as shown in Figure 6, the maximum length (front-to-back length) of the conductive film 115 in the X direction is set to 990 mm and the maximum length (width) in the Y direction is set to 900 mm.

[0118] Furthermore, for FM broadcast waves (76 MHz to 108 MHz), reception is possible by causing the conductive film 115 to resonate, depending on the relationship between the wavelength of the FM broadcast wave and the size of the vehicle antenna device 100 installed in the opening 11 of the vehicle body 10. For this reason, if the wavelength of the FM broadcast wave is λ, the shortening factor of the wavelength λ is k, and N is an arbitrary positive integer, then, as an example, the length of the outer edge of the conductive film 115 should be set to approximately kNλ. As shown in Figure 6, by setting the length of the conductive film 115 in the X direction (front-to-back length) to 990 mm and the length in the Y direction (width) to 900 mm, it is possible to satisfy this relationship, and it becomes possible to cause resonance of the FM broadcast wave and receive it.

[0119] Here, a feed element 120FM for FM broadcast waves is shown, but instead of the feed element 120FM, or in addition to the feed element 120FM, a feed element for DAB Band III (174 MHz to 240 MHz) broadcast waves may also be included, and the conductive film 115 may receive the radio waves of DAB Band III broadcast waves, which can then be extracted by the feed element for DAB Band III broadcast waves. The frequency of DAB Band III broadcast waves can also be received in the same way as FM broadcast waves by resonating the conductive film 115 in relation to the wavelength and the size of the vehicle antenna device 100.

[0120] <Reception of DTV broadcast waves> The receiving element 130DTV receives terrestrial digital television (DTV) broadcast waves (radio waves). The receiving element 130DTV is an antenna that receives DTV broadcast waves independently and is not electrically connected to the conductive film 115.

[0121] DTV broadcast waves (470 MHz to 710 MHz) are easier to design when the conductive film 115 is resonated independently rather than resonating, given the size of the vehicle antenna device 100 installed in the opening 11 of the vehicle body 10. For this reason, the receiving element 130DTV is composed of a dipole antenna having a feed point 131DTV and a dipole-type antenna element 132DTV.

[0122] Figure 6 shows, as an example, a diversity antenna configured by arranging two receiving elements 130DTV at each of the four corners of the vehicle antenna device 100. At each of the four corners, one of the two receiving elements 130DTV extends in the X direction, and the other receiving element 130DTV extends in the Y direction.

[0123] In this description, we will explain a configuration in which the receiving element 130DTV is configured as a dipole antenna. However, if a feed element 120 for DTV can be configured, the DTV broadcast wave may be received using the feed element 120 for DTV and the conductive film 115 instead of the receiving element 130DTV. In this case, the configuration may include the feed element 120 for DTV, but may not include the vehicle antenna device 100, feed elements 120AM and 120FM.

[0124] <Positions of the power supply elements 120AM and 120FM and the receiving element 130DTV in the Z direction> The positions of the power supply elements 120AM and 120FM and the receiving element 130DTV in the Z direction on the laminated glass 110 can be any of the multiple positions in the Z direction where the power supply element 120 can be placed, as explained using Figure 2. The positions of the power supply elements 120AM and 120FM and the receiving element 130DTV in the Z direction may be different from each other, but if they are the same, the application of silver paste by screen printing and firing can be performed simultaneously, simplifying the manufacturing process and reducing manufacturing costs. Next, the positions of the power supply elements 120AM and 120FM and the receiving element 130DTV in the XY plane and the relationship between the power supply elements 120AM, 120FM, and 130DTV and the conductive film 115 will be explained.

[0125] <Position of the power supply element 120AM in the XY plane> The power supply element 120AM is a linear power supply element that extends in the Y direction at the -X direction end of the laminated glass 110 and overlaps with the conductive film 115.

[0126] The power supply element 120AM extends parallel to the edge of the conductive film 115 that extends in the Y direction on the -X direction side of the outer edge. The power supply element 120AM also extends parallel to the edge of the laminated glass 110 that extends in the Y direction on the -X direction side of the outer edge. Since the outer edge of the laminated glass 110 extends along the opening edge of the opening 11, the power supply element 120AM extends parallel to the edge of the opening 11 that extends in the Y direction on the -X direction side of the opening edge.

[0127] The power supply element 120AM has a power supply point 121AM. One end of the power supply line is connected to the power supply point 121AM. The other end of the power supply line is connected to a receiver (not shown). If the power supply element 120AM is located on the main surface 112B of the glass plate 112, the power supply line can be connected to the power supply point 121AM by soldering or the like. If the power supply element 120AM is located on the main surface 112A of the glass plate 112, or on the main surface 111B of the glass plate 111, a flat harness or the like can be inserted between the glass plates 111 and 112 as the power supply line and connected to the power supply point 121AM. Note that if the power supply line is connected DC-wise to the conductive film 115, the power supply line may be connected to the power supply point 121AM. If the power supply line is connected to the power supply point 121AM, the power supply element 120AM is not required.

[0128] The power supply element 120AM is formed, for example, on the main surface 112B of the glass plate 112 to achieve an electrical connection with the conductive film 115, and the distance in the Z direction from the conductive film 115 is set to 2 mm. The power supply element 120AM is connected to the conductive film 115 at high frequency, for example, with a ceramic layer 114, an interlayer 113, and the glass plate 112 sandwiched between them.

[0129] <Position of the power supply element 120FM in the XY plane> The power supply element 120FM is, for example, a linear power supply element that extends in the Y direction at the -X direction end of the laminated glass 110, and more specifically, it extends in the Y direction at a position on the -X direction side of the conductive film 115. The power supply element 120FM does not overlap with the conductive film 115 in a plan view.

[0130] The power supply element 120FM has a power supply point 121FM. One end of the power supply line is connected to the power supply point 121FM. The other end of the power supply line is connected to a receiver (not shown). If the power supply element 120FM is located on the main surface 112B of the glass plate 112, the power supply line can be connected to the power supply point 121FM by soldering or the like. Alternatively, if the power supply element 120FM is located on the main surface 112A of the glass plate 112, or the main surface 111B of the glass plate 111, a flat harness or the like can be sandwiched between the glass plates 111 and 112 as the power supply line and connected to the power supply point 121FM.

[0131] To achieve an electrical connection with the conductive film 115, the power supply element 120FM is positioned, for example, on the main surface 112B of the glass plate 112, at a position 5 mm in the -X direction from the edge of the conductive film 115's outer edge that extends in the Y direction on the -X direction side, in a plan view, and extends parallel to the edge of the outer edge that extends in the Y direction on the -X direction side. The power supply element 120FM is thus positioned close to the outer edge of the conductive film 115, and for example, is connected to the conductive film 115 at high frequency with the ceramic layer 114, the interlayer 113, and the glass plate 112 sandwiched between them.

[0132] <Position of receiving element 130DTV in the XY plane> As described above, two receiving elements 130DTV are arranged at each of the four corners of the laminated glass 110 of the vehicle antenna device 100. The receiving elements 130DTV are not electrically connected to the conductive film 115.

[0133] To achieve an electrically disconnected state with the conductive film 115, the receiving elements 130DTVs are, for example, positioned at the four corners of the laminated glass 110 such that the shortest distance between the receiving element 130DTV closest to the conductive film 115 in a plan view and the conductive film 115 is 40 mm. The shortest distance is made large to sufficiently reduce the coupling between the receiving elements 130DTVs and the conductive film 115. The shortest distance between the receiving element 130DTV closest to the conductive film 115 in a plan view and the conductive film 115 is the distance between the part of the receiving element 130DTV closest to the conductive film 115 in a plan view and the part of the conductive film 115 closest to the receiving element 130DTV.

[0134] As described above, the receiving element 130DTV can be placed at any of the multiple positions in the Z direction of the laminated glass 110 on which the receiving element 130DTV can be placed, as explained with reference to Figure 2, but it is preferable that it be provided at the same position in the Z direction as the power supply elements 120AM and 120FM.

[0135] <Measurement Results for AM Broadcast Waves> Figure 7 shows an example of the frequency characteristics of the open-circuit voltage (dBμVemf) measured at the feed point 121AM, which is the signal extracted by capacitive coupling of the feed element 120AM with the signal received by the conductive film 115. The frequency characteristics of the open-circuit voltage of the conductive film 115 receiving the AM broadcast wave were measured while the frequency of the AM broadcast wave was varied, and the frequency characteristics of the open-circuit voltage were determined. In addition, the characteristics were determined for various lengths in the Y direction by changing the length of the feed element 120AM in the Y direction. In Figure 7, the open-circuit voltage measured at the feed point 121AM was converted to the open-circuit voltage when receiving the electric field of an AM broadcast wave of 60 dBμV / m.

[0136] For the measurements, a rectangular copper foil with a length of 990 mm in the X direction and 900 mm in the Y direction was used as the conductive film 115. As shown in Figure 6, the power supply element 120AM was placed in a position overlapping with the conductive film 115, with a 2.2 mm thick polyvinyl chloride resin sheet sandwiched between it and the conductive film 115. This simulates the state in which the power supply element 120AM is placed on the main surface 112B of the glass plate 112, using a resin sheet instead of the glass plate 112. With the resin sheet sandwiched between the glass plate 112 in this manner, the width of the power supply element 120AM in the X direction was fixed at 15 mm, and measurements were performed by setting the length L in the Y direction to 900 mm, 600 mm, 300 mm, 200 mm, 100 mm, 50 mm, and 30 mm.

[0137] Furthermore, a copper foil pad was attached to the conductive film 115, and a power supply line was directly connected to the pad. The open-circuit voltage was measured with the power supply line extending along the opening edge of the opening 11. The measurement results in this case are shown in Figure 7 as a direct connection.

[0138] Measurements were performed with AM broadcast frequencies set to 594 kHz, 693 kHz, 765 kHz, 810 kHz, 954 kHz, 1134 kHz, 1242 kHz, and 1422 kHz. In all cases, including when the Y-direction length L of the power supply element 120AM was 900 mm, 600 mm, 300 mm, 200 mm, 100 mm, 50 mm, and 30 mm, and in the case of direct connection, almost no difference in open-circuit voltage due to frequency differences was observed.

[0139] Furthermore, the open-circuit voltage was highest at all frequencies when directly connected. When the length L in the Y direction of the power supply element 120AM was 900 mm, 600 mm, 300 mm, 200 mm, 100 mm, 50 mm, and 30 mm, the open-circuit voltage was highest at the longest length L of 900 mm, and the open-circuit voltage decreased as the length L decreased.

[0140] Even when the length L in the Y direction of the power supply element 120AM was the shortest at 30 mm, a good value of approximately 35 dBμVemf or higher was obtained, confirming that AM broadcast waves can be received using the power supply element 120AM with copper foil acting as the conductive film 115.

[0141] <Simulation of FM and DAB broadcast waves> <Simulation model> Figure 8 shows an example of a simulation model including a vehicle antenna device 100 and a vehicle body 10. In Figure 8, as with Figures 3A and 6, the +X direction is forward, the -X direction is backward, the +Y direction is left, and the -Y direction is right.

[0142] The simulation model shown in Figure 8 includes a vehicle body 10 having an opening 11, a conductive film 115 of the vehicle antenna device 100, and power supply elements 120FM and 120DAB, with other components omitted. The reason for referring to the power supply elements as 120FM and 120DAB is that either power supply element 120FM or power supply element 120DAB will be used in the simulation.

[0143] Let X0 be the length of the opening 11 in the X direction, and Y0 be the length in the Y direction. As an example, the standard value for length X0 is 1000 mm, and the standard value for length Y0 is 1000 mm. The gap between the opening edge of the opening 11 and the conductive film 115 on the +X, +Y, and -Y sides is 10 mm in all cases. The gap between the opening edge of the opening 11 and the conductive film 115 on the -X side is 100 mm, and the power supply elements 120FM and 120DAB are provided in this 100 mm gap.

[0144] The power supply elements 120FM and 120DAB are, for example, L-shaped elements. The portion indicated by the triangle is the power supply point, located near the +X direction of the approximate center of the end edge extending in the Y direction on the -X direction side of the opening 11. The power supply elements 120FM and 120DAB extend in the +X direction from the power supply point, bend perpendicularly in the +Y direction, and extend in the +Y direction. The distance in the X direction between the end edge extending in the Y direction on the -X direction side of the opening 11 and the portion of the power supply elements 120FM and 120DAB that extends in the Y direction is 90 mm. Let La be the length of the portion of the power supply elements 120FM and 120DAB that extends in the Y direction.

[0145] Figures 9A and 9B show examples of simulation results of the frequency characteristics of the gain of the power supply element 120FM when the length La in the Y direction of the power supply element 120FM is changed. Figures 9C and 9D show examples of simulation results of the frequency characteristics of the gain of the power supply element 120DAB when the length La in the Y direction of the power supply element 120DAB is changed.

[0146] Figure 9A shows an example of the calculated frequency characteristics of the gain of the feed element 120FM when receiving a horizontally polarized FM broadcast wave. Figure 9B shows an example of the calculated frequency characteristics of the gain of the vehicle antenna device 100 when receiving a vertically polarized FM broadcast wave. Figure 9C shows an example of the calculated frequency characteristics of the gain of the feed element 120DAB when receiving a horizontally polarized DAB broadcast wave. Figure 9D shows an example of the calculated frequency characteristics of the gain of the feed element 120DAB when receiving a vertically polarized DAB broadcast wave.

[0147] Furthermore, the Y-direction lengths La of the power supply elements 120FM and 120DAB were set to 100 mm, 140 mm, 200 mm, 260 mm, 320 mm, 380 mm, 440 mm, and 500 mm. As the length La increases, the +Y-direction end of the length La portion approaches the edge of the opening 11 that extends in the X-direction on the +Y-direction side, but does not make contact.

[0148] As shown in Figure 9A, it was confirmed that the horizontal polarization gain in the FM broadcast band tended to increase as the length La increased. The gain was approximately -9 dB or higher at 88 MHz and approximately -15 dB or higher at 108 MHz, which were good values. However, when the length La reached 440 mm or 500 mm, the tip approached the aperture 11, causing some disturbance in the frequency characteristics.

[0149] As shown in Figure 9B, it was confirmed that the gain of vertical polarization in the FM broadcast wave band tended to increase as the length La increased. The gain was approximately -17.5 dB or higher at 88 MHz and approximately -18 dB or higher at 108 MHz, which were good values. However, when the length La reached 440 mm or 500 mm, the tip approached the aperture 11, causing some disturbance in the frequency characteristics.

[0150] As shown in Figure 9C, a tendency was observed for the horizontal polarization gain of the DAB broadcast wave band to decrease as the length La increased. This is thought to be because the DAB broadcast wave has a higher frequency than the FM broadcast wave, making a shorter length La more suitable. Gain values ​​ranging from approximately -17 dB to approximately -5 dB were obtained, which were good values. Furthermore, when the length La reached 440 mm or 500 mm, the tip approached the aperture 11, causing some disturbance in the frequency characteristics.

[0151] As shown in Figure 9D, a tendency was observed for the gain of the vertical polarization in the DAB broadcast wave band to decrease as the length La increased. This is thought to be because the DAB broadcast wave has a higher frequency than the FM broadcast wave, making a shorter length La more suitable. Gain values ​​were obtained in the range of approximately -25 dB to approximately -8 dB, which is slightly lower than the horizontal polarization, but still a good value. Furthermore, when the length La reached 440 mm or 500 mm, the tip approached the aperture 11, causing some disturbance in the frequency characteristics.

[0152] Figures 10A and 10B show examples of simulation results of the gain characteristics of the vehicle antenna device 100 when the length X0 in the X direction of the aperture 11 is changed. Figure 10A shows the gain of the vehicle antenna device 100 when the conductive film 115 receives horizontally polarized FM broadcast waves, and Figure 10B shows the gain obtained by the vehicle antenna device 100 when the conductive film 115 receives vertically polarized FM broadcast waves.

[0153] The length X0 was varied from 200 mm to 1600 mm. In this case, the length of the conductive film 115 in the X direction was also varied simultaneously, with the gap between the opening 11 and the conductive film 115 fixed at 10 mm on the +X side and the gap on the -X side fixed at 100 mm. In addition, the distance in the X direction between the portion of the power supply element 120FM extending in the Y direction and the opening 11 was fixed at 90 mm. The length La was fixed at 440 mm.

[0154] Furthermore, when the length X0 was varied from 200 mm to 1600 mm, the frequency of the FM broadcast wave was also varied, and the average gain of the vehicle antenna device 100 obtained at multiple frequencies for each length X0 was taken as the gain of the vehicle antenna device 100 at that length X0. The FM broadcast wave frequencies were calculated in 2 MHz increments from 88 MHz to 108 MHz.

[0155] As shown in Figure 10A, the gain characteristics of the vehicle antenna device 100 with respect to length X0 in the case of horizontal polarization showed a peak at length X0 of approximately 900 mm. Also, as shown in Figure 10B, the gain characteristics of the vehicle antenna device 100 with respect to length X0 in the case of vertical polarization showed a peak at length X0 of approximately 900 mm.

[0156] It was found that changing the length X0 of the aperture 11 in the X direction changes the frequency characteristics of the gain of the vehicle antenna device 100. This was confirmed because the resonance of the conductive film 115 is utilized, and changing the length X0 changes the frequency characteristics of the gain of the vehicle antenna device 100. It was found that the total circumference of the outer edge of the conductive film 115 is shorter than 1kλ, where λ is the wavelength of the radio waves received by the conductive film 115 in free space and k is the shortening factor of wavelength λ. This is because the conductive film 115 is coupled to the power supply element 120FM.

[0157] Figures 11A and 11B show examples of simulation results of the gain characteristics of the vehicle antenna device 100 when the length X0 of the aperture 11 in the X direction is changed. Figure 11A shows the gain of the vehicle antenna device 100 when the conductive film 115 receives horizontally polarized DAB broadcast waves, and Figure 11B shows the gain of the vehicle antenna device 100 when the conductive film 115 receives vertically polarized DAB broadcast waves.

[0158] The length X0 was varied from 200 mm to 1000 mm. In this case, the length of the conductive film 115 in the X direction was also varied simultaneously, with the gap between the opening 11 and the conductive film 115 fixed at 10 mm on the +X side and the gap on the -X side fixed at 100 mm. In addition, the distance in the X direction between the portion of the power supply element 120DAB extending in the Y direction and the opening 11 was fixed at 90 mm. The length La was fixed at 160 mm.

[0159] Furthermore, when the length X0 was varied from 200 mm to 1000 mm, the frequency of the DAB broadcast wave was also varied, and the average gain of the vehicle antenna device 100 obtained at multiple frequencies for each length X0 was taken as the gain of the vehicle antenna device 100 at that length X0. The DAB broadcast wave frequencies were calculated in 2 MHz increments from 170 MHz to 240 MHz.

[0160] As shown in Figure 11A, the gain characteristics of the vehicle antenna device 100 with respect to length X0 in the case of horizontal polarization showed a peak at length X0 of approximately 900 mm. Also, as shown in Figure 11B, the gain characteristics of the vehicle antenna device 100 with respect to length X0 in the case of vertical polarization showed a characteristic with multiple maximum values, but also a peak at length X0 of approximately 900 mm.

[0161] It was found that, even in the case of DAB broadcast waves, changing the length X0 in the X direction of the aperture 11 changes the frequency characteristics of the gain of the vehicle antenna device 100, similar to the case of FM broadcast waves. This was confirmed because the resonance of the conductive film 115 is utilized, and changing the length X0 changes the frequency characteristics of the gain of the vehicle antenna device 100. It was found that the total circumference of the outer edge of the conductive film 115 is shorter than 1kλ, where λ is the wavelength of the radio waves received by the conductive film 115 in free space and k is the shortening factor of wavelength λ. This is because the conductive film 115 is coupled to the power supply element 120DAB.

[0162] Figures 12A and 12B show examples of simulation results of the gain characteristics of the vehicle antenna device 100 when the length Y0 of the aperture 11 in the Y direction is changed. Figure 12A shows the gain of the vehicle antenna device 100 when the conductive film 115 receives horizontally polarized DAB broadcast waves, and Figure 12B shows the gain of the vehicle antenna device 100 when the conductive film 115 receives vertically polarized DAB broadcast waves.

[0163] The length Y0 was varied from 400 mm to 1000 mm. In this case, the length of the conductive film 115 in the Y direction was also varied simultaneously, and the gaps between the opening 11 and the conductive film 115 in the +Y direction and the -Y direction were fixed at 10 mm. In addition, the distance in the X direction between the portion of the power supply element 120DAB that extends in the Y direction and the opening 11 was fixed at 90 mm. The length La was fixed at 160 mm.

[0164] Furthermore, when the length Y0 was varied from 200 mm to 1000 mm, the frequency of the DAB broadcast wave was also varied, and the average gain of the vehicle antenna device 100 obtained at multiple frequencies for each length Y0 was taken as the gain of the vehicle antenna device 100 at that length Y0. The DAB broadcast wave frequencies were calculated in 2 MHz increments from 170 MHz to 240 MHz.

[0165] As shown in Figure 12A, the gain characteristics of the vehicle antenna device 100 with respect to length Y0 in the case of horizontal polarization showed that the gain was minimum at approximately -17 dB when the length Y0 was approximately 400 mm, the gain increased sharply when the length Y0 was longer than approximately 400 mm, and when the length Y0 was longer than approximately 500 mm, the gain of the vehicle antenna device 100 increased gradually with increasing length Y0. Furthermore, as shown in Figure 12B, the gain characteristics of the vehicle antenna device 100 with respect to length Y0 in the case of vertical polarization showed that the gain of the vehicle antenna device 100 was minimum at approximately -10 dB when the length Y0 was approximately 400 mm, the gain of the vehicle antenna device 100 increased sharply when the length Y0 was longer than approximately 400 mm, and when the length Y0 was longer than approximately 600 mm, the gain of the vehicle antenna device 100 decreased gradually with increasing length Y0.

[0166] It was found that changing the length Y0 of the aperture 11 in the Y direction changes the frequency characteristics of the gain of the vehicle antenna device 100. Furthermore, when the length Y0 is about 400 mm, the portion of the aperture edge of the aperture 11 on the +Y direction side approaches the feed element 120DAB, which is thought to have reduced the sensitivity of the conductive film 115 and caused a sharp decrease in the gain of the vehicle antenna device 100. Since the length of the aperture 11 in the Y direction is constrained by the width of the vehicle body 10, it was found that a good reception state can be achieved by ensuring a certain length Y0.

[0167] <Effects> The vehicle antenna device 100 of this embodiment is a vehicle antenna device 10 that is attached to a vehicle body 10 having an opening 11 provided in a first metal member of the roof of the vehicle body 10 and an opening 12 provided in a second metal member on the side of the vehicle body 10 and adjacent to the opening 11, and includes laminated glass 110 provided in the opening 11, a conductive film 115 made of a conductive film provided on the laminated glass 110, and a power supply element 120 (120AM, 120FM, 120DAB) provided on the laminated glass 110 and having a section that extends along the opening edge of the opening 11 and is electrically connected to the conductive film 115. The openings 11 and 12 of the vehicle body have an area that is sufficiently large with respect to the wavelength of the frequency band of the powered signal, and the conductive film 115 placed in the opening 11 adjacent to the opening 12 becomes capable of receiving horizontally polarized radio waves arriving from the horizontal direction and vertically polarized radio waves. Furthermore, since the power supply element 120 and the conductive film 115 are electrically connected, it becomes possible to receive radio waves in the frequency band that resonates at the outer edge of the conductive film 115. Also, the conductive film 115 is powered by the power supply element 120, and the conductive film 115 is able to radiate radio waves. Moreover, since the power supply element 120 and the conductive film 115 are provided on the laminated glass 110, they do not protrude from the vehicle body 10.

[0168] Therefore, an aesthetically pleasing vehicle antenna device 100 can be provided. Furthermore, the conductive film 115 coupled to the power supply element 120 provided on the laminated glass 110 can transmit and receive horizontally polarized and vertically polarized radio waves, and in particular, even if the power supply element 120 and the conductive film 115 are arranged parallel to the horizontal plane, it is possible to transmit and receive vertically polarized radio waves.

[0169] Furthermore, the power supply elements 120 (120AM, 120FM, 120DAB) may be linear. The linear nature of the power supply elements 120 (120AM, 120FM, 120DAB) allows them to be positioned in the small space surrounding the conductive film 115 in a plan view of the laminated glass 110.

[0170] Furthermore, the power supply element 120 (120AM, 120FM, 120DAB) may be a monopole type power supply element. This allows for a stronger coupling between the power supply element 120 and the metal part (ground plane) of the vehicle body 10, making it possible to increase the gain of vertically polarized radio waves in particular.

[0171] Furthermore, the aforementioned section of the power supply element 120 (120AM, 120FM, 120DAB) may extend parallel to the opening edge of the opening 11. A stronger connection is formed between the power supply element 120 (120AM, 120FM, 120DAB) and the opening 11 and the metal part (ground plane) of the vehicle body 10, making it possible to increase the gain.

[0172] Furthermore, the power supply elements 120 (120AM, 120FM, 120DAB) may be arranged along the outer edge of the conductive film 115. A stronger bond is formed between the power supply elements 120 (120AM, 120FM, 120DAB) and the conductive film 115, making it possible to further increase the gain of radio waves.

[0173] Furthermore, the power supply elements 120 (120AM, 120FM, 120DAB) may be arranged parallel to the outer edge of the conductive film 115. A stronger bond is formed between the power supply elements 120 (120AM, 120FM, 120DAB) and the conductive film 115, making it possible to further increase the gain of radio waves.

[0174] Furthermore, the power supply elements 120 (120AM, 120FM, 120DAB) may be arranged to overlap with the conductive film 115 in a plan view, or they may be arranged in a position that does not overlap with the conductive film 115 in a plan view. Either arrangement will form a stronger bond between the power supply elements 120 (120AM, 120FM, 120DAB) and the conductive film 115, making it possible to further increase the gain of radio waves.

[0175] Furthermore, the power supply element 120 (120AM, 120FM, 120DAB) may have one or more power supply elements for the first frequency band (one or more of one of 120AM, 120FM, and 120DAB), a first power supply element for the first and second frequency bands (one power supply element that receives multiple frequency bands), or one or more power supply elements for the second frequency band (one or more of the other of 120AM, 120FM, and 120DAB). As a result, the coupling of the power supply element for the first frequency band to the metal part (ground plane) of the vehicle body 10, and the coupling of the power supply element for the second frequency band to the metal part (ground plane) of the vehicle body 10, makes it possible to receive horizontally polarized and vertically polarized radio waves in the first and second frequency bands. Therefore, we can provide a vehicle antenna device 100 that is aesthetically pleasing and capable of transmitting and receiving horizontally and vertically polarized radio waves in multiple frequency bands.

[0176] Furthermore, the conductive film 115 may resonate in the first and second frequency bands. This provides a vehicle antenna device 100 that is aesthetically pleasing and capable of transmitting and receiving horizontally and vertically polarized radio waves in multiple frequency bands.

[0177] Furthermore, the device may also include a receiving element 130DTV provided on the laminated glass 110. This provides a vehicle antenna device 100 that can receive radio waves from the receiving element 130DTV, has a good appearance, and can transmit and receive radio waves in multiple frequency bands, including DTV.

[0178] Furthermore, the laminated glass 110 may further include a ceramic layer 114 formed on the main surface on the interior side of the vehicle, and the power supply elements 120 (120AM, 120FM, 120DAB) may be formed on the interior surface of the ceramic layer 114 in a plan view. When viewed from the exterior, the power supply elements 120 (120AM, 120FM, 120DAB) are concealed by the ceramic layer 114, resulting in an even better appearance.

[0179] Furthermore, at least a portion of the power supply element 120 (120AM, 120FM, 120DAB) may be located in a region that does not overlap with the ceramic layer 114 of the laminated glass 110. It is possible to realize a configuration in which at least a portion of the power supply element 120 (120AM, 120FM, 120DAB) is located inside the ceramic layer 114 provided at the periphery of the laminated glass 110.

[0180] Furthermore, the dielectric substrate may be tempered glass. Using tempered glass, a vehicle antenna device 100 with a good appearance can be provided.

[0181] Furthermore, the laminated glass 110 is a laminated glass comprising a glass plate 111 having a main surface 111A on the exterior side of the vehicle interior and a main surface 111B on the interior side of the vehicle interior, a glass plate 112 located on the interior side of the glass plate 111 and having a main surface 112A on the exterior side of the vehicle interior and a main surface 112B on the interior side of the vehicle interior, and an interlayer 113 provided between the glass plate 111 and the glass plate 112, and further comprising a ceramic layer 114 formed on the main surface 111B, main surface 112A, or main surface 112B, and the power supply element 120 (120AM, 120FM, 120DAB) has the ceramic layer 114 formed on the main surface 111B If the ceramic layer 114 is formed on the interior surface of the ceramic layer 114 in a plan view, it is formed on the portion of the main surface 112A or the main surface 112B that overlaps with the ceramic layer 114 in a plan view. If the ceramic layer 114 is formed on the main surface 112A, it is formed on the portion of the main surface 112B that overlaps with the ceramic layer 114 in a plan view, or it is formed on the main surface 112A and covered by the ceramic layer 114. If the ceramic layer 114 is formed on the main surface 112B, it may be formed on the interior surface of the ceramic layer 114 in a plan view. The dielectric substrate includes laminated glass 110, and when viewed from the outside, the power supply element 120 (120AM, 120FM, 120DAB) is concealed by the ceramic layer 114, providing a vehicle antenna device 100 with an even better appearance.

[0182] Furthermore, if λ is the wavelength of the radio wave in free space, the lateral length of the aperture 12 when viewed from the front may be between 0.05λ and 0.25λ. By setting the lateral length of the aperture 12 to a value within this range, a good average gain can be obtained.

[0183] Another embodiment of the vehicle antenna device 100 is a vehicle antenna device 10 that is attached to a vehicle body 10 having an opening 11 provided in a first metal member of the roof of the vehicle body 10 and an opening 12 provided in a second metal member on the side of the vehicle body 10 and adjacent to the opening 11, and includes laminated glass 110 provided in the opening 11, a conductive film 115 made of a conductive film provided on the laminated glass 110, and a feed line provided on the laminated glass 110, extending along the opening edge of the opening 11 and connected to the conductive film 115. The openings 11 and 12 of the vehicle body have an area sufficiently large with respect to the wavelength of the frequency band of the signal being fed, and the conductive film 115, which is placed in the opening 11 adjacent to the opening 12, is able to receive horizontally polarized radio waves arriving from the horizontal and vertically polarized radio waves. Furthermore, since the feed line and the conductive film 115 are electrically connected, it is possible to receive radio waves in the frequency band that resonates at the outer edge of the conductive film 115. Furthermore, the conductive film 115 is powered by the power supply line, and the conductive film 115 is capable of emitting radio waves. Moreover, since the power supply line and the conductive film 115 are installed on the laminated glass 110, they do not protrude from the vehicle body 10.

[0184] Therefore, an aesthetically pleasing vehicle antenna device 100 can be provided. Furthermore, the conductive film 115 coupled to the feed line provided on the laminated glass 110 can transmit and receive horizontally polarized and vertically polarized radio waves, and in particular, even if the feed line and the conductive film 115 are arranged parallel to the horizontal plane, it is possible to transmit and receive vertically polarized radio waves.

[0185] The vehicle 1 of the embodiment includes a vehicle body 10 and a vehicle antenna device 100. The vehicle body 10 has an opening 11 provided in a first metal member of the roof and an opening 12 provided in a second metal member of the side and adjacent to the opening 11. The vehicle antenna device 100 includes laminated glass 110 provided in the opening 11, a conductive film 115 made of a conductive film provided on the laminated glass 110, and a power supply element 120 (120AM, 120FM, 120DAB) provided on the laminated glass 110, extending along the opening edge of the opening 11 and electrically connected to the conductive film 115. The openings 11 and 12 of the vehicle body have an area sufficiently large with respect to the wavelength of the frequency band of the powered signal, and the conductive film 115 placed in the opening 11 adjacent to the opening 12 is capable of receiving horizontally polarized radio waves arriving from the horizontal direction and vertically polarized radio waves. Furthermore, since the power supply element 120 and the conductive film 115 are electrically connected, it becomes possible to receive radio waves in the frequency band that resonates at the outer edge of the conductive film 115. Also, the conductive film 115 is powered by the power supply element 120, and the conductive film 115 is able to radiate radio waves. Moreover, since the power supply element 120 and the conductive film 115 are provided on the laminated glass 110, they do not protrude from the vehicle body 10.

[0186] Therefore, a vehicle 1 including an aesthetically pleasing vehicle antenna device 100 can be provided. Furthermore, the conductive film 115 coupled to the power supply element 120 provided on the laminated glass 110 is capable of transmitting and receiving horizontally polarized and vertically polarized radio waves, and in particular, even if the power supply element 120 and the conductive film 115 are arranged parallel to the horizontal plane, it is possible to transmit and receive vertically polarized radio waves.

[0187] While exemplary vehicle antenna devices and vehicles have been described above, this disclosure is not limited to the specifically disclosed embodiments, and various modifications and changes are possible without departing from the scope of the claims.

[0188] The following additional notes are disclosed with respect to the above embodiments. (Note 1) A vehicle antenna device attached to a vehicle body having a first opening provided in a first metal member of the roof portion of the vehicle body and a second opening provided in a second metal member of the side portion of the vehicle body and adjacent to the first opening, the vehicle antenna device comprising: a dielectric substrate provided in the first opening; a conductive film provided on the dielectric substrate; and a feeding element provided on the dielectric substrate, having a section extending along the opening edge of the first opening, and electrically connected to the conductive film. (Note 2) The vehicle antenna device according to Note 1, wherein the feeding element is linear. (Note 3) The vehicle antenna device according to Note 1 or 2, wherein the feeding element is a monopole type feeding element. (Note 4) The vehicle antenna device according to any one of Notes 1 to 3, wherein the section of the feeding element extends parallel to the opening edge of the first opening. (Note 5) The vehicle antenna device according to any one of Notes 1 to 4, wherein the feeding element is arranged along the outer edge of the conductive film. (Note 6) The vehicle antenna device according to Note 5, wherein the feeding element is arranged parallel to the outer edge of the conductive film. (Note 7) The vehicle antenna device according to any one of Notes 1 to 6, wherein the feeding element is arranged to overlap with the conductive film in a plan view, or to a position that does not overlap with the conductive film in a plan view. (Note 8) The vehicle antenna device according to any one of Notes 1 to 7, wherein the feeding element comprises one or more first feeding elements for the first frequency band, first feeding elements for the first frequency band and the second frequency band, or one or more second feeding elements for the second frequency band. (Note 9) The vehicle antenna device according to Note 8, wherein the conductive film resonates in the first frequency band and the second frequency band. (Note 10) The vehicle antenna device according to any one of Notes 1 to 9, further comprising a receiving element provided on the dielectric substrate. (Note 11) The vehicle antenna device according to any one of Notes 1 to 10, further comprising a shielding layer formed on the main surface of the dielectric substrate on the vehicle interior side, wherein the power supply element is formed on the vehicle interior side surface of the shielding layer in a plan view.(Note 12) The vehicle antenna device according to Note 11, wherein at least a portion of the power supply element is located in a region of the dielectric substrate that does not overlap with the shielding layer. (Note 13) The vehicle antenna device according to any one of Notes 1 to 12, wherein the dielectric substrate is tempered glass. (Note 14) The dielectric substrate is a laminated glass comprising: a first glass plate having a first main surface on the exterior side of the vehicle interior and a second main surface on the interior side of the vehicle interior; a second glass plate located on the interior side of the vehicle interior than the first glass plate and having a third main surface on the exterior side of the vehicle interior and a fourth main surface on the interior side of the vehicle interior; and an interlayer provided between the first glass plate and the second glass plate, further comprising a shielding layer formed on the second main surface, the third main surface, or the fourth main surface, the power supply element being formed on the interior side of the shielding layer in a plan view when the shielding layer is formed on the second main surface, or on the portion of the third main surface or the fourth main surface that overlaps with the shielding layer in a plan view, the shielding layer being formed on the third main surface, or on the third main surface and covered by the shielding layer (Note 15) A vehicle antenna device according to any one of the appendices 1 to 14, wherein, when the shielding layer is formed on the fourth main surface, it is formed on the interior surface of the shielding layer in a plan view. (Note 16) A vehicle antenna device according to any one of the appendices 1 to 14, wherein, when the wavelength of the radio wave in free space is λ, the lateral length of the second opening in a front view of the second opening is 0.05λ or more and 0.25λ or less. (Note 17) A vehicle antenna device attached to a vehicle body having a first opening provided in a first metal member of the roof of the vehicle body and a second opening provided in a second metal member of the side of the vehicle body and adjacent to the first opening, comprising: a dielectric substrate provided in the first opening; a conductive film composed of a conductive film provided on the dielectric substrate; and a feed line provided on the dielectric substrate, extending along the opening edge of the first opening and connected to the conductive film.(Note 17) A vehicle comprising a vehicle body and a vehicle antenna device, wherein the vehicle body has a first opening provided in a first metal member of the roof and a second opening provided in a second metal member of the side and adjacent to the first opening, and the vehicle antenna device has a dielectric substrate provided in the first opening, a conductive film composed of a conductive film provided on the dielectric substrate, and a power supply element provided on the dielectric substrate, extending along the opening edge of the first opening and electrically connected to the conductive film.

[0189] According to the present invention, it is possible to provide a vehicle antenna device and a vehicle with a good appearance.

[0190] 1 Vehicle 10 Body 11, 12, 13F, 13R Opening 11A Flange 20 Adhesive 50SIM Simulation model of vehicle antenna device for comparison 51 Metal plate 52 Opening 100 Vehicle antenna device 100SIM Simulation model of vehicle antenna device 110 Laminated glass 111 Glass plate (Example of first glass plate) 111A Main surface (Example of first main surface) 111B Main surface (Example of second main surface) 112 Glass plate (Example of second glass plate) 112A Main surface (Example of third main surface) 112B Main surface (Example of fourth main surface) 113 Interlayer 114 Ceramic layer (Example of shielding layer) 114A Inner edge 115 Conductive film 120, 120AM, 120FM, 120DAB Power supply element 120SIM Antenna element simulation model 121AM, 121FM Feed point 130DTV Receiving element 131DTV Feed point 132DTV Antenna element

Claims

1. A vehicle antenna device to be attached to a vehicle body having a first opening provided in a first metal member of the roof portion of the vehicle body and a second opening provided in a second metal member of the side portion of the vehicle body and adjacent to the first opening, the vehicle antenna device comprising: a dielectric substrate provided in the first opening; a conductive film provided on the dielectric substrate; and a power supply element provided on the dielectric substrate, having a section extending along the opening edge of the first opening, and electrically connected to the conductive film.

2. The vehicle antenna device according to claim 1, wherein the power supply element is linear.

3. The vehicle antenna device according to claim 1, wherein the power supply element is a monopole type power supply element.

4. The vehicle antenna device according to claim 1, wherein the section of the power supply element extends parallel to the opening edge of the first opening.

5. The vehicle antenna device according to any one of claims 1 to 4, wherein the power supply element is arranged along the outer edge of the conductive film.

6. The vehicle antenna device according to claim 5, wherein the power supply element is arranged parallel to the outer edge of the conductive film.

7. The vehicle antenna device according to claim 1, wherein the power supply element is arranged to overlap with the conductive film in a plan view, or is arranged in a position that does not overlap with the conductive film in a plan view.

8. The vehicle antenna device according to claim 1, wherein the power supply element comprises one or more first power supply elements for a first frequency band, first power supply elements for a first frequency band and a second frequency band, or one or more second power supply elements for a second frequency band.

9. The vehicle antenna device according to claim 8, wherein the conductive film resonates in the first frequency band and the second frequency band.

10. The vehicle antenna device according to claim 1, further comprising a receiving element provided on the dielectric substrate.

11. The vehicle antenna device according to claim 1, further comprising a shielding layer formed on the main surface of the dielectric substrate on the vehicle interior side, wherein the power supply element is formed on the vehicle interior side surface of the shielding layer in a plan view.

12. The vehicle antenna device according to claim 11, wherein at least a portion of the power supply element is located in a region of the dielectric substrate that does not overlap with the shielding layer.

13. The vehicle antenna device according to claim 1, wherein the dielectric substrate is tempered glass.

14. The dielectric substrate is a laminated glass comprising: a first glass plate having a first main surface on the exterior side of the vehicle interior and a second main surface on the interior side of the vehicle interior; a second glass plate located on the interior side of the vehicle interior than the first glass plate and having a third main surface on the exterior side of the vehicle interior and a fourth main surface on the interior side of the vehicle interior; and an interlayer provided between the first glass plate and the second glass plate, further comprising a shielding layer formed on the second main surface, the third main surface, or the fourth main surface, the power supply element being formed on the interior side of the shielding layer in a plan view when the shielding layer is formed on the second main surface, or on the portion of the third main surface or the fourth main surface that overlaps with the shielding layer in a plan view, the power supply element being formed on the portion of the fourth main surface that overlaps with the shielding layer in a plan view when the shielding layer is formed on the third main surface, or being formed on the third main surface and covered by the shielding layer The vehicle antenna device according to claim 1, wherein, when the shielding layer is formed on the fourth main surface, it is formed on the surface of the shielding layer on the vehicle interior side in a plan view.

15. The vehicle antenna device according to claim 1, wherein, when the wavelength of the radio wave in free space is λ, the lateral length of the second aperture in a front view of the second aperture is 0.05λ or more and 0.25λ or less.

16. A vehicle antenna device attached to a vehicle body having a first opening provided in a first metal member of the roof portion of the vehicle body and a second opening provided in a second metal member of the side portion of the vehicle body and adjacent to the first opening, the vehicle antenna device comprising: a dielectric substrate provided in the first opening; a conductive film composed of a conductive film provided on the dielectric substrate; and a power supply line provided on the dielectric substrate, extending along the opening edge of the first opening and connected to the conductive film.

17. A vehicle comprising a vehicle body and a vehicle antenna device, wherein the vehicle body has a first opening provided in a first metal member of the roof and a second opening provided in a second metal member of the side and adjacent to the first opening, and the vehicle antenna device has a dielectric substrate provided in the first opening, a conductive film composed of a conductive film provided on the dielectric substrate, and a power supply element provided on the dielectric substrate, extending along the opening edge of the first opening and electrically connected to the conductive film.

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