Antenna device

Abstract

An antenna device mounted on a vehicle, said antenna device comprising: a first antenna that receives and / or transmits circularly polarized waves; a second antenna that receives and / or transmits circularly polarized waves; a third antenna that is located between the first antenna and the second antenna and receives and / or transmits linearly polarized waves; and a bracket that attaches the first antenna, the second antenna, and the third antenna to the vehicle.

Description

Antenna Device

[0001] The present invention relates to an antenna device.

[0002] In recent years, various antenna devices have been developed. For example, Patent Document 1 describes an antenna disposed inside an instrument panel of a vehicle. The antenna is attached to the instrument panel by a bracket.

[0003] Japanese Unexamined Patent Publication No. 2020-075519

[0004] A plurality of antennas may be attached to a vehicle in some cases. For example, as described in Patent Document 1, when a separate bracket is provided for each antenna, the number of attachment positions for the antennas on the vehicle increases, which may make it difficult to improve the workability of attaching the antennas to the vehicle. Furthermore, it is desirable that a plurality of antennas be arranged in a space-saving manner so that mutual interference between the plurality of antennas is suppressed.

[0005] An example of an object of the present invention is to arrange a plurality of antennas in a space-saving manner such that mutual interference between the plurality of antennas is suppressed, and to improve the workability of attaching the plurality of antennas to a vehicle. Other objects of the present invention will become apparent from the description of the present specification.

[0006] One aspect of the present invention is an antenna device mounted on a vehicle, comprising: a first antenna that performs at least one of receiving and transmitting circularly polarized waves; a second antenna that performs at least one of receiving and transmitting circularly polarized waves; a third antenna that is positioned between the first antenna and the second antenna, and performs at least one of receiving and transmitting linearly polarized waves; and a bracket that attaches the first antenna, the second antenna, and the third antenna to the vehicle.

[0007] According to the above aspect of the present invention, a plurality of antennas can be arranged in a space-saving manner such that mutual interference between the plurality of antennas is suppressed, and the workability of attaching the plurality of antennas to a vehicle can be improved.

[0008] This is a top view of a vehicle equipped with an antenna device according to an embodiment. This is an exploded perspective view of the antenna device according to an embodiment. This is an exploded perspective view of the GNSS antenna according to an embodiment. This is an exploded perspective view of the ETC antenna according to an embodiment. This is an exploded perspective view of the TEL antenna according to an embodiment. This is a top view of the TEL antenna according to an embodiment.

[0009] Embodiments of the present invention will be described below with reference to the drawings. In all drawings, similar components are denoted by the same reference numerals, and their descriptions are omitted where appropriate.

[0010] Figure 1 is a top view of a vehicle 2 equipped with an antenna device 1 according to an embodiment.

[0011] To explain the directions, we define the X, Y, and Z directions. The Z direction is parallel to the vertical direction. The X direction is one of the horizontal directions perpendicular to the Z direction. The Y direction is one of the horizontal directions perpendicular to both the Z and X directions. In this embodiment, the X direction is described as the front-back direction, the Y direction as the left-right direction, and the Z direction as the up-down direction. In Figure 1 and Figures 2 to 6 described later, the direction indicated by the X-axis arrow indicating the X direction, the direction indicated by the Y-axis arrow indicating the Y direction, and the direction indicated by the Z-axis arrow indicating the Z direction are defined as the front, left, and up directions, respectively. In Figure 1 and Figure 6 described later, the Z-axis, indicated by a white circle with a black dot, indicates that the Z-axis arrow is pointing towards the front of the paper.

[0012] Unless otherwise specified, the +X side or +X refers to the side indicated by the arrow on the X axis, and the -X side or -X refers to the opposite side of the side indicated by the arrow on the X axis. Unless otherwise specified, the +Y side or +Y refers to the side indicated by the arrow on the Y axis, and the -Y side or -Y refers to the opposite side of the side indicated by the arrow on the Y axis. Unless otherwise specified, the +Z side or +Z refers to the side indicated by the arrow on the Z axis, and the -Z side or -Z refers to the opposite side of the side indicated by the arrow on the Z axis.

[0013] As shown in Figure 1, when viewed from the +Z side, the antenna device 1 according to the embodiment is mounted inside the instrument panel 2a at the front of the vehicle 2 on the +X side. The instrument panel 2a is located on the -Y side with respect to the vehicle's central axis 2x. The vehicle's central axis 2x passes through the center of the vehicle 2 in the Y direction in the X direction when viewed from the +Z side, and is virtually illustrated in Figure 1 for illustrative purposes. The position in which the antenna device 1 is mounted on the vehicle 2 is not limited to the example shown in Figure 1. Hereafter, unless otherwise specified, the antenna device 1 according to the embodiment will be described as being mounted inside the instrument panel 2a.

[0014] Figure 2 is an exploded perspective view of the antenna device 1 according to this embodiment.

[0015] Referring to Figure 2, the antenna device 1 according to this embodiment will be described. Refer to Figure 1 as needed.

[0016] As shown in Figure 2, the antenna device 1 according to this embodiment includes a GNSS (Global Navigation Satellite System) antenna 10, an ETC (Electronic Toll Collection) antenna 20, a TEL (Telephone) antenna 30, and a bracket 40.

[0017] As will be explained in detail with reference to Figure 3 below, the GNSS antenna 10 is configured to transmit and receive circularly polarized signals for GNSS. Therefore, the GNSS antenna 10 is a circularly polarized antenna. As will be explained in detail with reference to Figure 4 below, the ETC antenna 20 is configured to transmit and receive circularly polarized signals for ETC. Therefore, the ETC antenna 20 is a circularly polarized antenna. As will be explained in detail with reference to Figure 5 below, the TEL antenna 30 is configured to transmit and receive linearly polarized signals for TEL. Therefore, the TEL antenna 30 is a linearly polarized antenna. The TEL antenna 30 is used, for example, in a MIMO (Multiple-Input and Multiple-Output) antenna.

[0018] As shown in Figure 2, when viewed from the +Z side, the TEL antenna 30 is located between the GNSS antenna 10 and the ETC antenna 20 in the Y direction. Therefore, compared to the case where the GNSS antenna 10 and the ETC antenna 20 are located close to each other without the TEL antenna 30 being between them, mutual interference between the radio waves of the GNSS antenna 10 and the ETC antenna 20 is suppressed. Furthermore, compared to the case where the GNSS antenna 10 and the ETC antenna 20 are located at a relatively large distance apart without the TEL antenna 30 being between them, the TEL antenna 30 can be placed in the space between the GNSS antenna 10 and the ETC antenna 20, allowing the GNSS antenna 10, ETC antenna 20, and TEL antenna 30 to be arranged in a space-saving manner.

[0019] As shown in Figure 2, when viewed from the +Z side, the GNSS antenna 10 is located on the -Y side relative to the TEL antenna 30. When viewed from the +Z side, the ETC antenna 20 is located on the +Y side relative to the TEL antenna 30. Therefore, when viewed from the +Z side, the ETC antenna 20 is located closer to the vehicle's central axis 2x than the GNSS antenna 10 and the TEL antenna 30. Consequently, compared to the case where the ETC antenna 20 is located on the -Y side relative to the TEL antenna 30, the ETC antenna 20 can be brought closer to the vehicle's central axis 2x, making it easier to transmit and receive radio waves from the ETC antenna 20. The GNSS antenna 10 may be located on the +Y side relative to the TEL antenna 30 and closer to the vehicle's central axis 2x than the ETC antenna 20 and the TEL antenna 30.

[0020] To suppress the influence on the radiation characteristics of the GNSS antenna 10, it is desirable that no metal is placed within a predetermined distance from the GNSS antenna 10. The TEL antenna 30 is located outside this range around the GNSS antenna 10. Therefore, even if there is metal in the TEL antenna 30, the influence on the radiation characteristics of the GNSS antenna 10 is suppressed. To suppress the influence on the radiation characteristics of the TEL antenna 30, it is desirable that no metal is placed within a predetermined distance from the TEL antenna 30. The GNSS antenna 10 is located outside this range around the TEL antenna 30. Therefore, even if there is metal in the GNSS antenna 10, the influence on the radiation characteristics of the TEL antenna 30 is suppressed.

[0021] In the example shown in Figure 2, when viewed from the +Z side, the GNSS antenna 10 is located almost directly to the side of the TEL antenna 30 on the -Y side, and the ETC antenna 20 is located almost directly to the side of the TEL antenna 30 on the +Y side. When viewed from the +Z side, the GNSS antenna 10 may be shifted to the +X side or -X side from the position directly to the side of the TEL antenna 30 on the -Y side. When viewed from the +Z side, the ETC antenna 20 may be shifted to the +X side or -X side from the position directly to the side of the TEL antenna 30 on the +Y side.

[0022] The bracket 40 is made of, for example, resin. The bracket 40 has a base 41 and a support 42. The GNSS antenna 10, ETC antenna 20, and TEL antenna 30 are located on the +Z side of the base 41. The support 42 protrudes downward on the -Z side from the rear end of the base 41 on the -X side. The support 42 is provided with four mounting holes 421 arranged in the Y direction. Fasteners such as bolts can be inserted through each mounting hole 421. The instrument panel 2a and the support 42 are fastened to each other by fasteners (not shown) inserted through each mounting hole 421. In this way, the bracket 40 attaches the GNSS antenna 10, ETC antenna 20, and TEL antenna 30 to the vehicle 2.

[0023] The configuration of the instrument panel 2a may vary depending on factors such as the type of vehicle 2. In this embodiment, the configuration of the support 42 is changed according to the configuration of the instrument panel 2a. This allows the GNSS antenna 10, ETC antenna 20, and TEL antenna 30 to be attached to the vehicle 2. Therefore, it is not necessary to change the configuration of the GNSS antenna 10, ETC antenna 20, and TEL antenna 30 according to the configuration of the instrument panel 2a. Consequently, the mass production capability of the antenna device 1 can be improved compared to the case where it is necessary to change the configuration of the GNSS antenna 10, ETC antenna 20, and TEL antenna 30 according to the configuration of the instrument panel 2a.

[0024] In this embodiment, a single bracket 40 is shared by the GNSS antenna 10, the ETC antenna 20, and the TEL antenna 30. Therefore, compared to the case where separate brackets are provided for the GNSS antenna 10, the ETC antenna 20, and the TEL antenna 30, the number of parts in the antenna device 1 can be reduced, and the antenna device 1 can be made more compact. Furthermore, the number of mounting positions for the antenna and the instrument panel 2a can be reduced, improving the ease of installation of the GNSS antenna 10, the ETC antenna 20, and the TEL antenna 30 to the vehicle 2.

[0025] Figure 3 is an exploded perspective view of the GNSS antenna 10 according to the embodiment. The GNSS antenna 10 according to the embodiment will be described with reference to Figure 3. Figures 1 and 2 will be referred to as necessary.

[0026] As shown in Figure 3, the GNSS antenna 10 according to this embodiment includes a GNSS plate 11, a GNSS case 12 and four GNSS screws 13, a GNSS substrate 14, a GNSS element 15 and a GNSS base 16.

[0027] The GNSS plate 11 is the ground plate for the GNSS antenna 10. The GNSS plate 11 is made of a conductor such as metal. The GNSS plate 11 is positioned approximately perpendicular to the Z direction. The GNSS plate 11 and the bracket 40 are separate components. Therefore, it is not necessary to change the GNSS plate 11 according to the configuration of the instrument panel 2a. Thus, the mass production capability of the antenna device 1 can be improved compared to the case where the GNSS plate 11 is changed. The GNSS plate 11 and the bracket 40 may be integrated. That is, the GNSS plate 11 may be a part of the bracket 40.

[0028] Viewed from the +Z side, the GNSS plate 11 has a substantially hexagonal shape, including a first front edge 11a, a first rear edge 11b, a pair of first rear lateral edges 11c, and a pair of first front lateral inclined edges 11d. Viewed from the +Z side, the first front edge 11a is located on the +X side of the GNSS plate 11 and is substantially parallel to the Y direction. Viewed from the +Z side, the first rear edge 11b is located on the -X side of the GNSS plate 11 and is substantially parallel to the Y direction. The dimension of the first front edge 11a in the Y direction is less than the dimension of the first rear edge 11b in the Y direction. Viewed from the +Z side, the pair of first rear lateral edges 11c are located on both sides in the Y direction of the -X side portion of the GNSS plate 11 and are substantially parallel to the X direction. Viewed from the +Z side, the pair of first front lateral inclined edges 11d are located on both sides in the Y direction of the +X side portion of the GNSS plate 11, and are inclined to move closer to each other as they move toward the +X side. In the example shown in Figure 3, viewed from the +Z side, the GNSS plate 11 has a substantially symmetrical shape with respect to a central axis passing through the center of the GNSS plate 11 in the Y direction in the X direction. Viewed from the +Z side, the GNSS plate 11 may have an asymmetrical shape.

[0029] The GNSS plate 11 defines seven first through holes 111. Viewed from the +Z side, the seven first through holes 111 are located at one vertex shared by the first quadrilateral 111a and the second quadrilateral 111b, which are hypothetically shown in Figure 3, at the remaining three vertices of the first quadrilateral 111a, and at the remaining three vertices of the second quadrilateral 111b. The first quadrilateral 111a has a roughly rectangular shape with a pair of long sides that are roughly parallel to the X direction and a pair of short sides that are roughly parallel to the Y direction. Viewed from the +Z side, the first quadrilateral 111a is located roughly in the center of the GNSS plate 11 in the Y direction. The second quadrilateral 111b has a roughly rectangular shape with a pair of long sides that are roughly parallel to the X direction and a pair of short sides that are roughly parallel to the Y direction. Viewed from the +Z side, the second quadrilateral 111b is offset to the +Y side from the center of the GNSS plate 11 in the Y direction. The first quadrilateral 111a and the second quadrilateral 111b share one vertex on the -X+Y side. Viewed from the +Z side, the -X side of the first quadrilateral 111a and the -X side of the second quadrilateral 111b are collinear. The -X side of the second quadrilateral 111b is shorter than the -X side of the first quadrilateral 111a. Viewed from the +Z side, the +Y side of the first quadrilateral 111a and the +Y side of the second quadrilateral 111b are collinear. The longer side on the +Y side of the second quadrilateral 111b is shorter than the longer side on the +Y side of the first quadrilateral 111a.

[0030] The GNSS case 12 is radio wave transparent. The GNSS case 12 is located on the +Z side relative to the GNSS plate 11. The GNSS plate 11 and the GNSS case 12 are fastened to each other by four GNSS screws 13. The four GNSS screws 13 serve as fasteners for fastening the GNSS plate 11 and the GNSS case 12 to each other. The fasteners are not limited to screws such as GNSS screws 13, but may be other types of fasteners. The four GNSS screws 13 are inserted from the -Z side of the GNSS plate 11 into four first through holes 111 located at the four vertices of the first quadrilateral 111a, and are screwed into the GNSS case 12. The GNSS plate 11 and the GNSS case 12 define a housing space for housing the GNSS substrate 14, the GNSS element 15, and the GNSS base 16.

[0031] As shown in Figure 3, the GNSS plate 11 is provided with four second through holes 112 and two first positioning holes 113. In the example shown in Figure 3, viewed from the +Z side, the four second through holes 112 are located at both ends in the Y direction of the front end portion on the +X side of the GNSS plate 11 and at both ends in the Y direction of the rear end portion on the -X side of the GNSS plate 11. In the example shown in Figure 3, as viewed from the +Z side, the two first positioning holes 113 are located between the two second through holes 112 on the +X side in the Y direction and on the +X side relative to the second through hole 112 on the -X+Y side. As shown in Figure 2, the first mounting area 411 on the base 41 on which the GNSS antenna 10 is mounted is provided with four first screw holes 411a and two first positioning pins 411b.

[0032] As can be seen in Figure 2, the GNSS antenna 10 and the first mounting area 411 are fastened to each other by four first bracket screws 51. The four first bracket screws 51 serve as fasteners for fastening the GNSS antenna 10 and the first mounting area 411 to each other. The fasteners are not limited to screws such as the first bracket screws 51, but may be other types of fasteners. As can be seen in Figures 2 and 3, the four first bracket screws 51 are inserted through four second through holes 112 from the +Z side of the GNSS plate 11 and screwed into four first screw holes 411a. As can be seen in Figures 2 and 3, in the mounting of the GNSS antenna 10 and the first mounting area 411, the GNSS antenna 10 and the first mounting area 411 are positioned relative to each other by inserting two first positioning pins 411b through two first positioning holes 113.

[0033] The GNSS substrate 14 is a rigid substrate such as a PCB (Printed Circuit Board). The GNSS substrate 14 is positioned on the +Z side relative to the GNSS plate 11, with the GNSS base 16 positioned between the GNSS plate 11 and the GNSS substrate 14 in the Z direction. The GNSS substrate 14 is positioned approximately perpendicular to the Z direction. When viewed from the +Z side, the GNSS substrate 14 has a roughly rectangular shape with a pair of sides that are roughly parallel to the X direction and a pair of sides that are roughly parallel to the Y direction.

[0034] The GNSS element 15 is located on the +Z side of the GNSS substrate 14. The GNSS element 15 is a patch antenna. When viewed from the +Z side, the GNSS element 15 has a roughly quadrilateral shape with a pair of sides that are roughly parallel to the X direction and a pair of sides that are roughly parallel to the Y direction.

[0035] A low-noise amplifier (LNA) is provided on the -Z plane side of the GNSS substrate 14. From the viewpoint shown in Figure 3, the LNA is located behind the GNSS substrate 14. Furthermore, a shielding case covering the LNA is provided on the -Z plane side of the GNSS substrate 14. From the viewpoint shown in Figure 3, the shielding case is located behind the GNSS substrate 14.

[0036] The GNSS base 16 is made of resin and is located between the GNSS plate 11 and the GNSS substrate 14 in the Z direction. Three protrusions 161 are provided on the -X, -Y, and +Y faces of the GNSS base 16. The +Z face of each protrusion 161 defines two base grooves 162 aligned perpendicular to the Z direction. Three case notches 121 are provided on the lower edge of the -Z side of the -X face of the GNSS case 12, the lower edge of the -Z side of the -Y face of the GNSS case 12, and the lower edge of the -Z side of the +Y face of the GNSS case 12. The -Z side portion of each case notch 121 is open to the -Z side. The +Z side portion of each case notch 121 includes two first case holes 122 aligned perpendicular to the Z direction. When the GNSS plate 11 and the GNSS case 12 are fastened together, the sides of the three protrusions 161 perpendicular to the Z direction are exposed through the three case notches 121, and in each case notch 121 and each base groove 162, the two first case holes 122 and the two base grooves 162 overlap each other in the Z direction to form two holes.

[0037] The GNSS antenna 10 is provided with two cables (not shown) that are electrically connected to the GNSS substrate 14 by soldering or other means. When the GNSS plate 11 and the GNSS case 12 are fastened together, these two cables can be routed out from two holes formed by two first case holes 122 and two base grooves 162 in one of the three case notches 121 and three protrusions 161, which overlap each other in the Z direction.

[0038] Figure 4 is an exploded perspective view of the ETC antenna 20 according to the embodiment. The ETC antenna 20 according to the embodiment will be described with reference to Figure 4. Figures 1 and 2 will be referred to as necessary.

[0039] As shown in Figure 4, the ETC antenna 20 according to this embodiment includes an ETC plate 21, an ETC case 22, four ETC screws 23, an ETC circuit board 24, an ETC element 25, an ETC cable 26, and an ETC base 27.

[0040] The ETC plate 21 is a base plate for the ETC antenna 20. The ETC plate 21 is made of a conductor such as metal. The ETC plate 21 is positioned approximately perpendicular to the Z direction. The ETC plate 21 and the bracket 40 are separate components. Therefore, it is not necessary to change the ETC plate 21 according to the configuration of the instrument panel 2a. Thus, the mass production efficiency of the antenna device 1 can be improved compared to the case where the ETC plate 21 is changed. The ETC plate 21 and the bracket 40 may be integrated. That is, the ETC plate 21 may be a part of the bracket 40.

[0041] Viewed from the +Z side, the ETC plate 21 has a substantially hexagonal shape including a second front edge 21a, a second rear edge 21b, a pair of second rear lateral edges 21c, and a pair of second front lateral inclined edges 21d. Viewed from the +Z side, the second front edge 21a is located on the +X side of the ETC plate 21 and is substantially parallel to the Y direction. Viewed from the +Z side, the second rear edge 21b is located on the -X side of the ETC plate 21 and is substantially parallel to the Y direction. The Y-direction dimension of the second front edge 21a is less than the Y-direction dimension of the second rear edge 21b. Viewed from the +Z side, the pair of second rear lateral edges 21c are located on both sides of the -X side portion of the ETC plate 21 in the Y direction and are substantially parallel to the X direction. Viewed from the +Z side, the pair of second front lateral inclined edges 21d are located on both sides in the Y direction of the +X side portion of the ETC plate 21, and are inclined to move closer to each other as they move toward the +X side. In the example shown in Figure 4, viewed from the +Z side, the ETC plate 21 has a substantially symmetrical shape with respect to a central axis passing through the center of the ETC plate 21 in the Y direction in the X direction. Viewed from the +Z side, the ETC plate 21 may have an asymmetrical shape.

[0042] The ETC plate 21 defines seven third through holes 211. Viewed from the +Z side, the seven third through holes 211 are located at one vertex shared by the third quadrilateral 211a and the fourth quadrilateral 211b, which are hypothetically shown in Figure 4, at the remaining three vertices of the third quadrilateral 211a, and at the remaining three vertices of the fourth quadrilateral 211b. The third quadrilateral 211a has a roughly rectangular shape with a pair of long sides that are roughly parallel to the X direction and a pair of short sides that are roughly parallel to the Y direction. Viewed from the +Z side, the third quadrilateral 211a is located roughly in the center of the ETC plate 21 in the Y direction. The fourth quadrilateral 211b has a roughly rectangular shape with a pair of long sides that are roughly parallel to the X direction and a pair of short sides that are roughly parallel to the Y direction. Viewed from the +Z side, the fourth quadrilateral 211b is offset to the +Y side from the center of the ETC plate 21 in the Y direction. The third quadrilateral 211a and the fourth quadrilateral 211b share one vertex on the -X+Y side. Viewed from the +Z side, the -X side of the third quadrilateral 211a and the -X side of the fourth quadrilateral 211b are collinear. The -X side of the fourth quadrilateral 211b is shorter than the -X side of the third quadrilateral 211a. Viewed from the +Z side, the +Y side of the third quadrilateral 211a and the +Y side of the fourth quadrilateral 211b are collinear. The longer side on the +Y side of the fourth quadrilateral 211b is shorter than the longer side on the +Y side of the third quadrilateral 211a.

[0043] The ETC case 22 is radio wave transparent. The ETC case 22 is located on the +Z side relative to the ETC plate 21. The ETC plate 21 and the ETC case 22 are fastened to each other by four ETC screws 23. The four ETC screws 23 serve as fasteners for fastening the ETC plate 21 and the ETC case 22 to each other. The fasteners are not limited to screws such as ETC screws 23, but may be other types of fasteners. The four ETC screws 23 are inserted from the -Z side into four third through holes 211 located at the four vertices of the fourth quadrilateral 211b and are screwed to the ETC case 22. The ETC plate 21 and the ETC case 22 define a housing space for housing the ETC substrate 24, ETC element 25, a portion of the ETC cable 26, and the ETC base 27.

[0044] As shown in FIG. 4, the ETC plate 21 is provided with four fourth through-holes 212 and two second positioning holes 213. In the example shown in FIG. 4, when viewed from the +Z side, the four fourth through-holes 212 are located at both end portions in the Y direction of the front end portion on the +X side of the ETC plate 21, and at both end portions in the Y direction of the rear end portion on the -X side of the ETC plate 21. In the example shown in FIG. 4, when viewed from the +Z side, the two second positioning holes 213 are located between the two +X-side fourth through-holes 212 in the Y direction, and on the +X side with respect to the -X+Y-side fourth through-hole 212. As shown in FIG. 2, the second mounting region 412 of the pedestal 41 where the ETC antenna 20 is mounted is provided with four second screw holes 412a and two second positioning pins 412b.

[0045] As can be seen from FIG. 2, the ETC antenna 20 and the second mounting region 412 are fastened to each other by four second bracket screws 52. The four second bracket screws 52 serve as fasteners for fastening the ETC antenna 20 and the second mounting region 412 to each other. The fasteners are not limited to screws such as the second bracket screws 52, and may be other types of fasteners. As can be seen from FIGS. 2 and 4, the four second bracket screws 52 are inserted into the four fourth through-holes 212 from the +Z side of the ETC plate 21, and screwed to the four second screw holes 412a. As can be seen from FIGS. 2 and 4, when mounting the ETC antenna 20 and the second mounting region 412, the two second positioning pins 412b are inserted into the two second positioning holes 213, thereby positioning the ETC antenna 20 and the second mounting region 412 relative to each other.

[0046] The ETC board 24 is a rigid board such as a PCB. The ETC board 24 is located on the +Z side with respect to the ETC plate 21, with the ETC base 27 positioned between the ETC plate 21 and the ETC board 24 in the Z direction. The ETC board 24 is inclined obliquely with respect to a plane perpendicular to the Z direction such that the +Z surface of the ETC board 24 faces obliquely upward toward the front. When viewed from the +Z side, the ETC board 24 has a substantially rectangular shape having a pair of sides substantially parallel to the X direction and a pair of sides substantially parallel to the Y direction.

[0047] The ETC element 25 is located on the +Z surface side of the ETC substrate 24. When viewed from the +Z side, the ETC element 25 has a substantially rectangular shape having a pair of sides substantially parallel to the X direction and a pair of sides substantially parallel to the Y direction. Similarly to the ETC substrate 24, the ETC element 25 is inclined obliquely with respect to a plane perpendicular to the Z direction such that the +Z surface of the ETC element 25 faces obliquely upward and forward.

[0048] One end of the ETC cable 26 is electrically connected to the ETC substrate 24 by conduction such as soldering. The ETC base is made of resin, and two base holes 271 are provided on each of the -X surface, -Y surface and +Y surface of the ETC base 27. Two second case holes 221 are provided on each of the -X surface, -Y surface and +Y surface of the ETC case 22. A groove for guiding the ETC cable 26 to any one of the six base holes 271 is defined on the -Z surface of the ETC base 27. In a state where the ETC plate 21 and the ETC case 22 are fastened to each other, by guiding the ETC cable 26 via the groove provided on the -Z surface side of the ETC base 27, the ETC cable 26 can be pulled out from any one of the six base holes 271 and any one of the six second case holes 221. By guiding the ETC cable 26 via the groove provided on the -Z surface of the ETC base 27, the ETC cable 26 can be easily pulled out from the accommodation space defined by the ETC plate 21 and the ETC case 22 through any one of the six base holes 271 and any one of the six second case holes 221.

[0049] The GNSS antenna 10 and the ETC antenna 20 will be described with reference to FIG. 3 and FIG. 4.

[0050] As can be seen from Figures 3 and 4, when viewed from the +Z side, the GNSS plate 11 and the ETC plate 21 have substantially the same shape. Also, when viewed from the +Z side, the seven first through holes 111 and the seven third through holes 211 are located in substantially the same places on the GNSS plate 11 and the ETC plate 21. Also, when viewed from the +Z side, the four second through holes 112 and the four fourth through holes 212 are located in substantially the same places on the GNSS plate 11 and the ETC plate 21. Also, when viewed from the +Z side, the two first positioning holes 113 and the two second positioning holes 213 are located in substantially the same places on the GNSS plate 11 and the ETC plate 21. Therefore, the GNSS plate 11 can be used interchangeably with both the GNSS plate 11 and the ETC plate 21. Furthermore, the ETC plate 21 can be used interchangeably with both the GNSS plate 11 and the ETC plate 21.

[0051] As can be seen in Figures 3 and 4, four GNSS screws 13 are inserted through four first through holes 111 located at the four vertices of the first square 111a of the GNSS plate 11, or through four third through holes 211 located at the four vertices of the third square 211a of the ETC plate 21, and are screwed to the GNSS case 12. This makes the GNSS plate 11 and the ETC plate 21 usable for the GNSS antenna 10. Also, as can be seen in Figures 3 and 4, four ETC screws 23 are inserted through four first through holes 111 located at the four vertices of the second square 111b of the GNSS plate 11, or through four third through holes 211 located at the four vertices of the fourth square 211b of the ETC plate 21, and are screwed to the ETC case 22. As a result, the GNSS plate 11 and the ETC plate 21 can be used for the ETC antenna 20. Therefore, by appropriately selecting the first through-hole 111 in the GNSS plate 11 through which the GNSS screw 13 or ETC screw 23 is inserted, and the third through-hole 211 in the ETC plate 21 through which the GNSS screw 13 or ETC screw 23 is inserted, the GNSS plate 11 can be used for both the GNSS antenna 10 and the ETC antenna 20. Therefore, the ETC plate 21 can be used for both the GNSS antenna 10 and the ETC antenna 20.

[0052] In the example shown in Figure 3, one first through-hole 111 on the -X+Y side is located at a vertex shared by the first quadrilateral 111a and the second quadrilateral 111b. Therefore, compared to the case where eight first through-holes 111 are provided at the four vertices of the first quadrilateral 111a and the four vertices of the second quadrilateral 111b, with the first quadrilateral 111a and the second quadrilateral 111b not sharing any vertices, the number of first through-holes 111 can be reduced. This makes it easier to maintain the strength of the GNSS plate 11. Furthermore, if the first quadrilateral 111a and the second quadrilateral 111b do not share any vertices and are located approximately in the center of the GNSS plate 11 in the Y direction, then the first through-hole 111 located at the -X+Y vertex of the first quadrilateral 111a and the first through-hole 111 located at the -X+Y vertex of the second quadrilateral 111b may be connected to each other, or the first through-hole 111 located at the -X-Y vertex of the first quadrilateral 111a and the first through-hole 111 located at the -X-Y vertex of the second quadrilateral 111b may be connected to each other. By having one first through-hole 111 on the -X+Y side located at a single vertex shared by the first quadrilateral 111a and the second quadrilateral 111b, it is possible to prevent the first through-hole 111 located at the -X-Y vertex of the first quadrilateral 111a and the first through-hole 111 located at the -X-Y vertex of the second quadrilateral 111b from connecting to each other. The same applies to the third through-hole 211 of the ETC plate 21.

[0053] As can be seen from Figure 4, the displacement of the fourth quadrilateral 211b from the center of the ETC plate 21 in the Y direction toward the +Y side causes the ETC case 22, ETC substrate 24, ETC element 25, and ETC base 27 to be shifted toward the +Y side from the center of the ETC plate 21 in the Y direction. Since the displacement of the fourth quadrilateral 211b from the center of the ETC plate 21 in the Y direction is small, its effect on the antenna characteristics of the ETC antenna 20 can be almost ignored. Furthermore, considering that the ETC element 25 should be brought close to the vehicle's central axis 2x, it is preferable that the fourth quadrilateral 211b is shifted toward the +Y side rather than toward the -Y side from the center of the ETC plate 21 in the Y direction.

[0054] As shown in Figure 3, the pair of first forward lateral inclined edges 11d provide a gradient between the +Y side edge of the +X portion of the GNSS plate 11 on the TEL antenna 30 side and the -Y side edge of the +X portion of the GNSS plate 11 on the opposite side of the TEL antenna 30 side. In the example shown in Figure 3, the first forward lateral inclined edge 11d on the +Y side corresponds to the gradient of the +Y side edge of the +X portion of the GNSS plate 11. Similarly, the first forward lateral inclined edge 11d on the -Y side corresponds to the gradient of the -Y side edge of the +X portion of the GNSS plate 11. Due to the pair of first forward lateral inclined edges 11d, the +X portion of the GNSS plate 11 tapers at least partially in the Y direction as it approaches the +X side. The first forward lateral inclined edge 11d on the -Y side suppresses interference between the -Y side edge of the +X side portion of the GNSS plate 11 and the instrument panel 2a, as well as interference between the -Y side edge of the +X side portion of the GNSS plate 11 and the internal components of the instrument panel 2a.

[0055] As shown in Figure 4, the pair of second front lateral inclined edges 21d provide a gradient between the -Y side edge of the +X side portion of the ETC plate 21 on the TEL antenna 30 side and the +Y side edge of the +X side portion of the ETC plate 21 on the opposite side of the TEL antenna 30 side. In the example shown in Figure 4, the second front lateral inclined edge 21d on the -Y side corresponds to the gradient of the -Y side edge of the +X side portion of the ETC plate 21. Similarly, the second front lateral inclined edge 21d on the +Y side corresponds to the gradient of the +Y side edge of the +X side portion of the ETC plate 21. Due to the pair of second front lateral inclined edges 21d, the +X side portion of the ETC plate 21 tapers at least partially in the Y direction as it approaches the +X side. The second forward lateral inclined edge 21d on the +Y side suppresses interference between the +Y side edge of the +X side portion of the ETC plate 21 and the instrument panel 2a, as well as interference between the +Y side edge of the +X side portion of the ETC plate 21 and the internal components of the instrument panel 2a.

[0056] As can be seen from Figures 2, 3, and 4, even when the GNSS plate 11 is used for the ETC antenna 20 on the +Y side relative to the TEL antenna 30, the first forward lateral inclined edge 11d provided on the +Y side edge of the +X side portion of the GNSS plate 11 suppresses interference between the +Y side edge of the +X side portion of the GNSS plate 11 and the instrument panel 2a, as well as interference between the +Y side edge of the +X side portion of the GNSS plate 11 and the internal components of the instrument panel 2a. Furthermore, even if the ETC plate 21 is used as the GNSS antenna 10 on the -Y side relative to the TEL antenna 30, the second forward lateral inclined edge 21d provided on the -Y side edge of the +X side portion of the ETC plate 21 suppresses interference between the -Y side edge of the +X side portion of the ETC plate 21 and the instrument panel 2a, as well as interference between the -Y side edge of the +X side portion of the ETC plate 21 and the internal components of the instrument panel 2a.

[0057] Figure 5 is an exploded perspective view of the TEL antenna 30 according to the embodiment. The TEL antenna 30 according to the embodiment will be described with reference to Figure 5. Figures 1 and 2 will be referred to as necessary.

[0058] As shown in Figure 5, the TEL antenna 30 includes a first TEL case 31, a second TEL case 32, four TEL screws 33, a first TEL circuit board 34, four first TEL elements 35, a first TEL cable 36, a second TEL circuit board 37, four second TEL elements 38, and a second TEL cable 39. The first TEL cable 36 is provided with a first ferrite core 361 to suppress noise current flowing through the first TEL cable 36. The second TEL cable 39 is provided with a second ferrite core 391 to suppress noise current flowing through the second TEL cable 39.

[0059] Figure 5 shows, for illustrative purposes, a hypothetical first board central axis 34x passing through the center of the first TEL board 34 in the X direction when viewed from the +Z side, and a hypothetical second board central axis 34y passing through the center of the first TEL board 34 in the Y direction when viewed from the +Z side. Also, for illustrative purposes, Figure 5 shows, for illustrative purposes, a hypothetical third board central axis 37x passing through the center of the second TEL board 37 in the X direction when viewed from the +Z side, and a hypothetical fourth board central axis 37y passing through the center of the second TEL board 37 in the Y direction when viewed from the +Z side.

[0060] The first TEL case 31 is radio wave transparent. The first TEL case 31 houses the first TEL substrate 34, four first TEL elements 35, a portion of the first TEL cable 36, and the first ferrite core 361. The first TEL case 31 is open on the +Z side. Viewed from the +Z side, the first TEL case 31 has a roughly rectangular shape with a pair of sides substantially parallel to the X direction and a pair of sides substantially parallel to the Y direction.

[0061] The second TEL case 32 is radio wave transparent. The second TEL case 32 houses the second TEL substrate 37, four second TEL elements 38, a portion of the second TEL cable 39, and the second ferrite core 391. The second TEL case 32 is open to the -Z side. Viewed from the -Z side, the second TEL case 32 has a substantially rectangular shape with a pair of sides substantially parallel to the X direction and a pair of sides substantially parallel to the Y direction.

[0062] The first TEL case 31 and the second TEL case 32 are fastened together by four TEL screws 33. The four TEL screws 33 serve as fasteners for fastening the first TEL case 31 and the second TEL case 32 together. The fasteners are not limited to screws such as TEL screws 33, but may be other types of fasteners. The four TEL screws 33 are inserted into the first TEL case 31 from the -Z side and screwed into the second TEL case 32. The first TEL case 31 and the second TEL case 32 define a housing space for housing the first TEL board 34, four first TEL elements 35, a portion of the first TEL cable 36, the first ferrite core 361, the second TEL board 37, four second TEL elements 38, a portion of the second TEL cable 39, and the second ferrite core 391. As can be seen from Figures 2 and 5, when the first TEL case 31 and the second TEL case 32 are fastened together, the first TEL cable 36 and the second TEL cable 39 can be pulled out from two third case holes 321 provided on the -X side of the first TEL case 31 and the second TEL case 32.

[0063] As shown in Figure 2, the TEL antenna 30 and the third mounting area 413 on the base 41 on which the TEL antenna 30 is mounted are fastened to each other by two third bracket screws 53. The two third bracket screws 53 serve as fasteners for fastening the TEL antenna 30 and the third mounting area 413 to each other. The fasteners are not limited to screws such as the third bracket screws 53, but may be other types of fasteners. As can be seen from Figures 2 and 5, the two third bracket screws 53 are inserted from the -Z side of the third mounting area 413 and screwed to the first TEL case 31.

[0064] The first TEL substrate 34 is a rigid substrate such as a PCB. The first TEL substrate 34 has a roughly rectangular shape with a pair of long sides substantially parallel to the X direction and a pair of short sides substantially parallel to the Y direction. When viewed from the +Z side, the first TEL substrate 34 is located substantially in the center of the first TEL case 31. Two first conductive patterns 341 are located on the +Z side of the first TEL substrate 34. The two first conductive patterns 341 are arranged substantially symmetrically with respect to the central axis 34x of the first substrate and extend in the X direction.

[0065] The four first TEL elements 35 are made of a conductor such as sheet metal. Viewed from the +Z side, the four first TEL elements 35 are arranged in approximately two rotational symmetry with respect to the center of the first TEL substrate 34. Specifically, viewed from the +Z side, the two first TEL elements 35 on the -Y side and the two first TEL elements 35 on the +Y side are arranged in approximately symmetrical manner with respect to the central axis 34x of the first substrate. Also, viewed from the +Z side, the two first TEL elements 35 on the -X side and the two first TEL elements 35 on the +X side are arranged in approximately symmetrical manner with respect to the central axis 34y of the second substrate.

[0066] Each first TEL element 35 includes a first base end portion 351 and a first tip portion 352. The X-direction ends of the first conductive pattern 341 on the -Y side and the first base end portions 351 of the two first TEL elements 35 on the -Y side are electrically connected to each other by conductivity such as soldering. The X-direction ends of the first conductive pattern 341 on the +Y side and the first base end portions 351 of the two first TEL elements 35 on the +Y side are electrically connected to each other by conductivity such as soldering. Viewed from the +Z side, the first tip portion 352 of each first TEL element 35 is located further from the first TEL substrate 34 than the first base end portion 351 of each first TEL element 35. Each first TEL element 35 extends from the first base end portion 351 to the first tip portion 352.

[0067] The approximate center portion in the X direction of each first conductive pattern 341 and one end of the first TEL cable 36 are electrically connected to each other by conductivity such as soldering. Therefore, the first conductive pattern 341 on the -Y side and the two first TEL elements 35 on the -Y side constitute a first TEL antenna element 301 with the approximate center portion in the X direction of the first conductive pattern 341 on the -Y side as the feed point. Also, the first conductive pattern 341 on the +Y side and the two first TEL elements 35 on the +Y side constitute a second TEL antenna element 302 with the approximate center portion in the X direction of the first conductive pattern 341 on the +Y side as the feed point. The first TEL antenna element 301 and the second TEL antenna element 302 can operate as two tapered slot antennas or two dipole antennas.

[0068] In each of the first TEL antenna element 301 and the second TEL antenna element 302, the width of each first TEL element 35 increases from the first base end 351 to the first tip end 352. Therefore, each first TEL element 35 has a self-similar shape or a similar shape. Due to the shape of the first TEL element 35, the first TEL antenna element 301 and the second TEL antenna element 302 operate as self-similar antennas or similar antennas. A "self-similar antenna" is an antenna whose shape remains similar even when the scale (size ratio) is changed, such as a biconical antenna or a bowtie antenna.

[0069] The second TEL substrate 37 is a rigid substrate such as a PCB. The second TEL substrate 37 has a roughly rectangular shape with a pair of short sides substantially parallel to the X direction and a pair of long sides substantially parallel to the Y direction. When viewed from the -Z side, the second TEL substrate 37 is located substantially in the center of the second TEL case 32. Two second conductive patterns 371 are located on the +Z side of the second TEL substrate 37. The two second conductive patterns 371 are arranged substantially symmetrically with respect to the fourth substrate central axis 37y and extend in the Y direction.

[0070] The four second TEL elements 38 are made of a conductor such as sheet metal. Viewed from the +Z side, the four second TEL elements 38 are arranged in approximately two rotational symmetry with respect to the center of the second TEL substrate 37. Specifically, viewed from the +Z side, the two second TEL elements 38 on the -Y side and the two second TEL elements 38 on the +Y side are arranged in approximately symmetrical manner with respect to the central axis 37x of the third substrate. Also, viewed from the +Z side, the two second TEL elements 38 on the -X side and the two second TEL elements 38 on the +X side are arranged in approximately symmetrical manner with respect to the central axis 37y of the fourth substrate.

[0071] Each second TEL element 38 includes a second base portion 381 and a second tip portion 382. The Y-direction ends of the second conductive pattern 371 on the -X side and the second base portions 381 of the two second TEL elements 38 on the -X side are electrically connected to each other by conduction such as soldering. The Y-direction ends of the second conductive pattern 371 on the +X side and the second base portions 381 of the two second TEL elements 38 on the +X side are electrically connected to each other by conduction such as soldering. Viewed from the +Z side, the second tip portion 382 of each second TEL element 38 is located further from the second TEL substrate 37 than the second base portion 381 of each second TEL element 38. Each second TEL element 38 extends from the second base portion 381 to the second tip portion 382.

[0072] The approximate center portion in the Y direction of each second conductive pattern 371 and one end of the second TEL cable 39 are electrically connected to each other by conductivity such as soldering. Therefore, the second conductive pattern 371 on the -X side and the two second TEL elements 38 on the -X side constitute a third TEL antenna element 303 with the approximate center portion in the Y direction of the second conductive pattern 371 on the -X side as the feed point. Also, the second conductive pattern 371 on the +X side and the two second TEL elements 38 on the +X side constitute a fourth TEL antenna element 304 with the approximate center portion in the Y direction of the second conductive pattern 371 on the +X side as the feed point. The third TEL antenna element 303 and the fourth TEL antenna element 304 can operate as two tapered slot antennas or two dipole antennas.

[0073] In both the third TEL antenna element 303 and the fourth TEL antenna element 304, the width of each second TEL element 38 increases from the second base end portion 381 toward the second tip portion 382. Therefore, each second TEL element 38 has a self-similar shape or a similar shape. Due to the shape of the second TEL element 38, the third TEL antenna element 303 and the fourth TEL antenna element 304 operate as self-similar antennas or similar antennas.

[0074] The first tip portion 352 of the first TEL element 35 on the -X-Y side and the second tip portion 382 of the second TEL element 38 on the -X-Y side are non-conductive and capacitively coupled to each other. Therefore, the first tip portion 352 of the first TEL element 35 on the -X-Y side and the second tip portion 382 of the second TEL element 38 on the -X-Y side form a split ring. Similarly, the first tip portion 352 of the first TEL element 35 on the -X+Y side and the second tip portion 382 of the second TEL element 38 on the -X+Y side, the first tip portion 352 of the first TEL element 35 on the +X-Y side and the second tip portion 382 of the second TEL element 38 on the +X-Y side, and the first tip portion 352 of the first TEL element 35 on the +X+Y side and the second tip portion 382 of the second TEL element 38 on the +X+Y side also form a split ring. Therefore, the first TEL antenna element 301, the second TEL antenna element 302, the third TEL antenna element 303, and the fourth TEL antenna element 304 as a whole can operate as an antenna similar to a loop antenna.

[0075] The TEL antenna 30 operates as a tapered slot antenna in relatively high frequency bands, as a loop antenna in relatively low frequency bands, and as a dipole antenna in the intermediate frequency band between the relatively high and relatively low frequency bands. Furthermore, the TEL antenna 30 operates as a composite antenna of a tapered slot antenna and a dipole antenna in the frequency band between the relatively high and intermediate frequency bands. In addition, the TEL antenna 30 operates as a composite antenna of a loop antenna and a dipole antenna in the frequency band between the relatively low and intermediate frequency bands. Therefore, the TEL antenna 30 can be used across a wide frequency band.

[0076] Figure 6 is a top view of the TEL antenna 30 according to an embodiment.

[0077] As shown in Figure 6, when viewed from the +Z side, the +X surfaces of the first TEL case 31 and the second TEL case 32 protrude at least partially to the +X side from the +X side front edge 41a of the base 41 on the +Z side. If the length in the X direction of the protruding portions of the first TEL case 31 and the second TEL case 32 from the front edge 41a of the base is relatively short, the protruding portions of the first TEL case 31 and the second TEL case 32 do not need to be supported by the base 41. Compared to the case where the base 41 supports the protruding portions of the first TEL case 31 and the second TEL case 32 from the front edge 41a of the base, the base 41 can be made smaller in the X direction. When viewed from the +Z side, the +X side portion of the GNSS antenna 10 and the +X side portion of the ETC antenna 20 may also protrude at least partially to the +X side from the front edge 41a of the base.

[0078] As shown in Figure 6, when viewed from the +Z side, the -X surfaces of the first TEL case 31 and the second TEL case 32 protrude at least partially to the -X side from the rear edge 41b of the base 41 on the -X side of the +Z surface. If the length in the X direction of the protruding portions of the first TEL case 31 and the second TEL case 32 from the rear edge 41b of the base is relatively short, the protruding portions of the first TEL case 31 and the second TEL case 32 do not need to be supported by the base 41. Compared to the case where the base 41 supports the protruding portions of the first TEL case 31 and the second TEL case 32 from the rear edge 41b of the base, the base 41 can be made smaller in the X direction. When viewed from the +Z side, the -X side portion of the GNSS antenna 10 and the -X side portion of the ETC antenna 20 may also protrude at least partially to the -X side from the rear edge 41b of the base.

[0079] The embodiments of the present invention have been described above with reference to the drawings, but these are merely examples of the present invention, and various other configurations can also be adopted.

[0080] In this embodiment, a GNSS antenna 10 and an ETC antenna 20 are exemplified as antennas for circular polarization, and a TEL antenna 30 is exemplified as an antenna for linear polarization. The antennas to which the matters described in this embodiment can be applied are not limited to the GNSS antenna 10, the ETC antenna 20, and the TEL antenna 30. The matters described in this embodiment can be applied to a plurality of antennas for circular polarization and to linear polarization antennas located between the circular polarization antennas.

[0081] In this embodiment, the bracket 40 connects the three antennas, the GNSS antenna 10, the ETC antenna 20, and the TEL antenna 30, to the vehicle 2. The bracket 40 may also be configured to connect four or more antennas, including a plurality of antennas for circular polarization and at least one antenna for linear polarization located between the circular polarization antennas, to the vehicle 2.

[0082] According to the present invention, an antenna device in the following embodiments is provided.

[0083] (Aspect 1) In aspect 1, the antenna device mounted on the vehicle comprises a first antenna that performs at least one of receiving and transmitting circularly polarized waves, a second antenna that performs at least one of receiving and transmitting circularly polarized waves, a third antenna located between the first antenna and the second antenna that performs at least one of receiving and transmitting linearly polarized waves, and a bracket for attaching the first antenna, the second antenna and the third antenna to the vehicle.

[0084] The "first antenna" corresponds to the "GNSS antenna" in the above-described embodiment. The "second antenna" corresponds to the "ETC antenna" in the above-described embodiment. The "third antenna" corresponds to the "TEL antenna" in the above-described embodiment.

[0085] According to the above embodiment, mutual interference between the first and second antennas is suppressed compared to the case where the first and second antennas are located close together without a third antenna between them. Furthermore, compared to the case where the first and second antennas are located at a relatively large distance apart without a third antenna between them, the first, second, and third antennas can be arranged in a space-saving manner. In addition, compared to the case where separate brackets are provided for the first, second, and third antennas, the number of mounting positions for the antennas and the vehicle can be reduced, improving the ease of mounting the first, second, and third antennas to the vehicle.

[0086] (Aspect 2) In aspect 2, the first antenna and the second antenna each have at least one of a first ground plate for the first antenna and a second ground plate for the second antenna.

[0087] The "first base plate" corresponds to the "GNSS plate" in the above-described embodiment. The "second base plate" corresponds to the "ETC plate" in the above-described embodiment.

[0088] According to the above-described embodiment, even if it is necessary to change the bracket configuration, it is not necessary to change the first and second ground plates. Therefore, the mass production capability of the antenna device can be improved compared to the case where the first and second ground plates are changed.

[0089] (Aspect 3) In aspect 3, the first floor plate and the second floor plate are substantially the same shape.

[0090] According to the above-described embodiment, the first ground plate can be used for both the first antenna and the second antenna, and the second ground plate can be used for both the first antenna and the second antenna.

[0091] (Aspect 4) In aspect 4, the edge of the first floor plate on the third antenna side and the edge of the first floor plate on the opposite side of the third antenna side include a slope that tapers the first floor plate at least partially, and the edge of the second floor plate on the third antenna side and the edge of the second floor plate on the opposite side of the third antenna side include a slope that tapers the second floor plate at least partially.

[0092] According to the above-described embodiment, interference between the edge of the first ground plate opposite to the third antenna side and the vehicle is suppressed. Also, interference between the edge of the second ground plate opposite to the third antenna side and the vehicle is suppressed. Furthermore, even if the first ground plate is used as the second antenna, interference between the edge of the first ground plate opposite to the aforementioned edge and the vehicle is suppressed. Also, even if the second ground plate is used as the first antenna, interference between the edge of the second ground plate opposite to the aforementioned edge and the vehicle is suppressed.

[0093] (Aspect 5) In aspect 5, each of the first floor plate and the second floor plate is provided with a plurality of holes, a fastener is inserted through at least one of the plurality of holes in the first floor plate, and a fastener is inserted through at least one of the plurality of holes in the second floor plate.

[0094] The "hole" in the "first base plate" corresponds to the "first through-hole" in the above-described embodiment. The "hole" in the "second base plate" corresponds to the "third through-hole" in the above-described embodiment. The "fastener" inserted through the "hole" in the "first base plate" corresponds to the "GNSS screw" in the above-described embodiment. The "fastener" inserted through the "hole" in the "second base plate" corresponds to the "ETC screw" in the above-described embodiment.

[0095] According to the above-described embodiment, by appropriately selecting the holes through which the fasteners in the first ground plate are inserted and the holes through which the fasteners in the second ground plate are inserted, the first ground plate can be used for both the first antenna and the second antenna, and the second ground plate can be used for both the first antenna and the second antenna.

[0096] (Aspect 6) In aspect 6, at least one of the first antenna, the second antenna, and the third antenna protrudes at least partially from the edge of the surface of the bracket on which the first antenna, the second antenna, and the third antenna are mounted.

[0097] According to the above-described embodiment, the bracket can be made smaller compared to the case where the bracket supports the protruding portion of the first antenna, the second antenna, or the third antenna.

[0098] (Aspect 7) In aspect 7, the first antenna or the third antenna is located closer to the center of the vehicle than the second antenna.

[0099] According to the above-described embodiment, if bringing the first antenna or the third antenna closer to the center of the vehicle makes it easier to transmit and receive radio waves from the first antenna or the third antenna, then it is possible to make it easier to transmit and receive radio waves from the first antenna or the third antenna.

[0100] (Aspect 8) In aspect 8, the first antenna is a GNSS antenna, the second antenna is an ETC antenna, and the third antenna is a TEL antenna.

[0101] According to the above-described embodiment, compared to the case where separate brackets are provided for the GNSS antenna, ETC antenna, and TEL antenna, the workability of attaching the GNSS antenna, ETC antenna, and TEL antenna to the vehicle can be improved.

[0102] This application claims priority based on Japanese Patent Application No. 2025-028577, filed on 26 February 2025, and incorporates all of its disclosures herein.

[0103] 1 Antenna device, 2 Vehicle, 2a Instrument panel, 2x Vehicle central axis, 10 GNSS antenna, 11 GNSS plate, 11a First front edge, 11b First rear edge, 11c First rear lateral edge, 11d First front lateral inclined edge, 111 First through hole, 111a First quadrilateral, 111b Second quadrilateral, 112 Second through hole, 113 First positioning hole, 12 GNSS case, 121 Case notch, 122 First case hole, 13 GNSS screw, 14 GNSS substrate, 15 GNSS element, 16 GNSS base, 161 Projection, 162 Base groove, 20 ETC antenna, 21 ETC plate, 21a Second front edge, 21b Second rear edge, 21c Second rear lateral edge, 21d 211 Second front lateral inclined edge, 211 Third through hole, 211a Third quadrilateral, 211b Fourth quadrilateral, 212 Fourth through hole, 213 Second positioning hole, 22 ETC case, 221 Second case hole, 23 ETC screw, 24 ETC substrate, 25 ETC element, 26 ETC cable, 27 ETC base, 271 Base hole, 30 TEL antenna, 301 First TEL antenna element, 302 Second TEL antenna element, 303 Third TEL antenna element, 304 Fourth TEL antenna element, 31 First TEL case, 32 Second TEL case, 321 Third case hole, 33 TEL screw, 34 First TEL substrate, 34x First substrate central axis, 34y Second substrate central axis, 341 First conductive pattern, 35 First TEL element, 351 352 First base portion, 36 First tip portion, 36 First TEL cable, 361 First ferrite core, 37 Second TEL substrate, 37x Third substrate central axis, 37y Fourth substrate central axis, 371 Second conductive pattern, 38 Second TEL element, 381 Second base portion, 382 Second tip portion, 39 Second TEL cable, 391 Second ferrite core, 40 Bracket, 41 Base, 41a Front edge of base, 41b Rear edge of base, 411 First mounting area, 411a First screw hole, 411b First positioning pin, 412 Second mounting area, 412a Second screw hole, 412b Second positioning pin, 413 Third mounting area, 42 Support, 421 Mounting hole, 51 First bracket screw, 52 Second bracket screw, 53 Third bracket screw

Claims

1. An antenna device mounted on a vehicle, comprising: a first antenna that performs at least one of receiving and transmitting circularly polarized waves; a second antenna that performs at least one of receiving and transmitting circularly polarized waves; a third antenna located between the first antenna and the second antenna that performs at least one of receiving and transmitting linearly polarized waves; and a bracket for attaching the first antenna, the second antenna and the third antenna to the vehicle.

2. The antenna device according to claim 1, wherein the first antenna and the second antenna each have at least one of a first ground plate for the first antenna and a second ground plate for the second antenna.

3. The antenna device according to claim 2, wherein the first and second ground plates are substantially the same shape.

4. The antenna device according to claim 2 or 3, wherein the edge of the first ground plate on the third antenna side and the edge of the first ground plate on the opposite side of the third antenna side include a slope that tapers the first ground plate at least partially, and the edge of the second ground plate on the third antenna side and the edge of the second ground plate on the opposite side of the third antenna side include a slope that tapers the second ground plate at least partially.

5. The antenna device according to claim 2 or 3, wherein each of the first and second floor plates is provided with a plurality of holes, a fastener is inserted through at least one of the plurality of holes in the first floor plate, and a fastener is inserted through at least one of the plurality of holes in the second floor plate.

6. The antenna device according to any one of claims 1 to 3, wherein at least one of the first antenna, the second antenna, and the third antenna protrudes at least partially from the edge of the surface of the bracket on which the first antenna, the second antenna, and the third antenna are mounted.

7. The antenna device according to any one of claims 1 to 3, wherein the first antenna or the third antenna is located closer to the center of the vehicle than the second antenna.

8. The antenna device according to any one of claims 1 to 3, wherein the first antenna is a GNSS antenna, the second antenna is an ETC antenna, and the third antenna is a TEL antenna.

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