CN120202596A - Antenna device - Google Patents

Abstract

The antenna device comprises a1 st base part having a1 st surface on which a radiation element is located and a2 nd surface opposite to the 1 st surface, and a2 nd base part having a 3 rd surface opposite to the 2 nd surface of the 1 st base part and a 4 rd surface opposite to the 3 rd surface, wherein the element is arranged on the 3 rd surface of the 2 nd base part, and the 1 st base part is provided with a containing part which contains the element and is formed by a dielectric medium.

Description

Antenna device

Technical Field

The present invention relates to an antenna device.

Background

Patent document 1 describes an antenna device including a patch antenna having a radiation element, and a substrate disposed in proximity to a rear surface side (a side opposite to a side where the radiation element is disposed) of the patch antenna.

Prior art literature

Patent literature

Patent document 1 Japanese patent laid-open No. 2008-263494

Disclosure of Invention

However, when the element is to be arranged on the front surface side of the substrate on which the patch antenna is arranged, the element needs to be arranged in a region where the patch antenna is not arranged or the patch antenna needs to be separated from the substrate, which leads to an increase in the size of the antenna device.

An object of the present invention is to easily achieve miniaturization of an antenna device. Other objects of the present invention will be apparent from the description of the present specification.

An antenna device according to one aspect of the present invention includes a1 st base portion having a1 st surface on which a radiation element is located and a2 nd surface opposite to the 1 st surface, and a2 nd base portion having a3 rd surface opposite to the 2 nd surface of the 1 st base portion and a4 th surface opposite to the 3 rd surface, wherein an element is disposed on the 3 rd surface of the 2 nd base portion, and the 1 st base portion includes a housing portion which houses the element and is formed of a dielectric.

According to the above aspect of the present invention, the antenna device can be easily miniaturized.

Drawings

Fig. 1 is a side view of an antenna device 100 according to embodiment 1 mounted on a front glass 90 of a vehicle.

Fig. 2A is a perspective view of the antenna device 100 according to embodiment 1.

Fig. 2B is a perspective view of the antenna device 100 of embodiment 1, viewed from another angle.

Fig. 3 is an exploded perspective view of the antenna device 100 according to embodiment 1.

Fig. 4A is a cross-sectional view of the antenna device 100 in line A-A of fig. 2A.

Fig. 4B is a cross-sectional view of the antenna device 100 in line B-B of fig. 2B.

Fig. 5A is a perspective view of the circuit board 40 held on the base portion 70, and the connector 60.

Fig. 5B is a perspective view of the circuit board 40 and the connector 60.

Fig. 6 is a perspective view of dielectric 12 formed in accommodating portion 13.

Fig. 7A is a perspective view of an antenna device 100A of comparative example 1.

Fig. 7B is an explanatory diagram of the antenna 10A and the circuit board 40A of comparative example 1.

Fig. 8 is an explanatory diagram of the antenna 10B and the circuit board 40B of comparative example 2.

Fig. 9 is an explanatory diagram of the antenna device 100 according to embodiment 1.

Fig. 10 is a diagram showing an example of directivity of the antenna 10 in embodiment 1.

Fig. 11A is a perspective view of an antenna 10C according to modification 1.

Fig. 11B is a perspective view of the antenna 10C of modification 1, which is seen from another angle.

Fig. 12 is a perspective view of an antenna 10D according to modification 2.

Fig. 13 is an explanatory diagram of an antenna device 100E according to embodiment 2.

Fig. 14 is an explanatory diagram of an antenna device 100F according to embodiment 3.

Fig. 15A is a perspective view of antenna 10F according to embodiment 3.

Fig. 15B is a perspective view of antenna 10F of embodiment 3 seen from another angle.

Detailed Description

At least the following matters will be apparent from the description of the present specification and the accompanying drawings.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The same or equivalent components, parts, and the like shown in the drawings are denoted by the same reference numerals, and repetitive description thereof will be omitted as appropriate.

= 1 St embodiment=

Fig. 1 is a side view of an antenna device 100 according to embodiment 1 mounted on a front glass 90 of a vehicle. Fig. 2A is a perspective view of the antenna device 100 according to embodiment 1. Fig. 2B is a perspective view of the antenna device 100 of embodiment 1, viewed from another angle. Fig. 3 is an exploded perspective view of the antenna device 100 according to embodiment 1. The broken lines (A-A line and B-B line) shown in fig. 2A are broken lines in the cross-sectional views shown in fig. 4A and 4B described later.

Definition of < direction, etc >

First, referring to fig. 1 to 3, the direction and the like in the antenna device 100 of the present embodiment are defined.

As shown in fig. 1, the direction in which the antenna 10 (described later) and the circuit board 40 (described later) are aligned and the direction from the circuit board 40 toward the antenna 10 is set to "+x direction". The directions perpendicular to the +x direction and perpendicular to each other are referred to as "+y direction" and "+z direction".

The opposite directions of +X direction, +Y direction and +Z direction are respectively-X direction, -Y direction and-Z direction. The +X direction, -X direction, +Y direction, -Y direction, +Z direction and-Z direction are each directions to be determined. In addition, the directions determined by the above-described directions are not necessarily called directions, and the two directions of the +x direction and the-X direction are simply called "X direction". Similarly, the +y direction and the-Y direction are simply referred to as "Y direction". The +z direction and the-Z direction are simply referred to as "Z directions".

In fig. 1 to 3, in order to facilitate understanding of the directions and the like in the antenna device 100, the directions of the +x direction, +y direction, and +z direction are indicated by line segments with arrows. Moreover, the intersection of these arrowed line segments does not mean the origin of coordinates.

In addition, the +x direction side of the antenna device 100 and the respective components of the antenna device 100 (for example, the antenna 10) may be referred to as "front side", and the-X direction side may be referred to as "back side". The surface on the +x direction side of the antenna 10 may be referred to as the "surface of the antenna 10", and the surface on the-X direction side of the antenna 10 may be referred to as the "back surface of the antenna 10". Similarly, the +x-direction side surface of the circuit board 40 is sometimes referred to as "the surface of the circuit board 40", and the-X-direction side surface of the circuit board 40 is sometimes referred to as "the back surface of the circuit board 40".

As will be described later, the antenna device 100 is disposed so that the +x direction is directed forward when viewed from the driver's seat of the vehicle, not shown. In this case, the +y direction in the antenna device 100 is directed leftward as viewed from the driver's seat of the vehicle, and the +z direction is directed upward as viewed from the driver's seat of the vehicle. Therefore, the +x direction may be referred to as the "front direction", the-X direction may be referred to as the "rear direction", and the X direction may be referred to as the "front-rear direction". Similarly, the +y direction is sometimes referred to as "left direction", the-Y direction is sometimes referred to as "right direction", the Y direction is sometimes referred to as "left-right direction", the +z direction is sometimes referred to as "up direction", the-Z direction is sometimes referred to as "down direction", and the Z direction is sometimes referred to as "up-down direction".

The above-described definition of the direction and the like is common to other embodiments of the present specification unless otherwise specified.

Summary of antenna device 100

Next, referring again to fig. 1 to 3 described above, and referring first to fig. 4A to 6, an outline of the antenna device 100 of the present embodiment will be described.

Fig. 4A is a cross-sectional view of the antenna device 100 in line A-A of fig. 2A. Fig. 4B is a cross-sectional view of the antenna device 100 in line B-B of fig. 2B. Fig. 5A is a perspective view of the circuit board 40 held on the base portion 70, and the connector 60. Fig. 5B is a perspective view of the circuit board 40 and the connector 60. Fig. 6 is a perspective view of dielectric 12 formed in accommodating portion 13.

The antenna device 100 is, for example, an antenna device for a vehicle not shown. The antenna device 100 is disposed at a predetermined position (for example, a front glass 90 described later) of the vehicle in a predetermined orientation, and is connected to an external module (in the present embodiment, a V2X controller or other device) not shown through a coaxial cable 6 having a signal line 7 and a ground line 8 shown in fig. 1.

Here, as shown in fig. 1, the antenna device 100 and the coaxial cable 6 are connected by connecting a connector 60 (described later) of the antenna device 100 to a cable-side connector 64 attached to an end portion of the coaxial cable 6. In the following description, "connected" is not limited to physical connection, but includes "electrical connection". The "electrical connection" may be any connection capable of transmitting an electrical signal, and includes connection via a conductor such as solder, a connector (here, the connector 60 and the cable-side connector 64), an electronic circuit, an electronic component, or the like, for example.

The antenna device 100 of the present embodiment is disposed above the front glass 90 of the vehicle (for example, near the rear view mirror) so that the +x direction is directed forward when viewed from the driver's seat of the vehicle. This makes it possible to make the main radiation direction of the antenna 10 described later forward as viewed from the driver's seat of the vehicle.

The position and the arrangement direction in which the antenna device 100 is arranged are not limited to the example of the present embodiment shown in fig. 1, and may be appropriately changed according to the environmental conditions of the communication target and the like envisaged. The antenna device 100 may be disposed in various positions such as a rear glass, a roof, an instrument panel, an upper portion of an instrument panel, a high-position instrument panel (overhead console), a bumper, a license plate mounting portion, a pillar portion, a spoiler portion, a door mirror portion, and a rear panel (REAR PARCELSHELF) portion of a vehicle, in addition to a front glass of the vehicle.

The antenna device 100 may be arranged in a rear glass in the vehicle such that the main radiation direction of the antenna 10 is directed rearward as viewed from the driver's seat of the vehicle, and the +x direction may be directed rearward as viewed from the driver's seat of the vehicle. The antenna device 100 may be disposed such that the main radiation direction of the antenna 10 is directed to the left or right as viewed from the driver's seat of the vehicle. The antenna device 100 may be disposed on the roof of a vehicle in a case of a structure that can ensure waterproof and dustproof performance conditions.

As shown in fig. 1, the antenna device 100 is attached to the front glass 90 by being connected to a vehicle-side connection portion 91 located on the vehicle (front glass 90) side via an antenna device-side connection portion 92 located on the antenna device 100 side. The vehicle-side connecting portion 91 is, for example, a resin member, and is fixed to the front glass 90. The antenna device side connection portion 92 is, for example, a bracket member made of resin, and the antenna device 100 is fixed to the antenna device side connection portion 92 by, for example, snap-fitting.

However, the fixing method of the antenna device 100 to the antenna device side connection portion 92 is not limited to the snap fit, and may be screw fastening, welding, adhesion, press fitting, or the like. The antenna device-side connection portion 92 may be a part of the antenna device 100 (a part of the housing portion 1 and the base portion 70 described later). That is, the antenna device 100 and the antenna device side connection portion 92 may be integrated, in which case the vehicle side connection portion 91 and the antenna device side connection portion 92 may be fixed by snap-fitting, screw fastening, welding, bonding, press-fitting, embedding, or the like. The antenna device 100 may be directly attached to the front glass 90 without the vehicle-side connection portion 91 and the antenna-device-side connection portion 92.

Here, the antenna device 100 is not limited to a mode of being mounted on a vehicle, but includes a mode of being carried into a vehicle and used in the vehicle. The antenna device 100 of the present embodiment is assumed to be used for a "vehicle" which is a wheeled passenger car, but is not limited to this, and may be used for a flying object such as an unmanned aerial vehicle, a detector, a vehicle such as a building without wheels, an agricultural machine, or a moving object such as a ship. The antenna device 100 may be used for an antenna device other than a mobile body.

As shown in fig. 3, the antenna device 100 includes a housing portion 1, an antenna 10, an adhesive portion 30, a circuit board 40, a connector 60, and a base portion 70.

< Housing portion 1>

The case portion 1 is a member that constitutes an exterior of the antenna device 100 together with the base portion 70. In the antenna device 100 of the present embodiment, the housing portion 1 is formed of a dielectric. Specifically, the housing portion 1 is formed of an insulating resin such as ABS resin. However, the housing 1 may be made of a material other than an insulating resin, which allows radio waves to pass through. The case portion 1 may be formed of a portion of an insulating resin and a portion of another material through which radio waves pass, and the components may be freely combined. As shown in fig. 3, the case portion 1 is located on the +x direction side of the antenna device 100.

As shown in fig. 2A, the housing portion 1 has housing-side claw portions 2. However, the case-side claw portion 2 is formed on the inner surface of the case portion 1, and is therefore illustrated by a broken line in fig. 2A. The housing-side claw portion 2 is a portion that engages with a base-side claw portion 71 (described later) of the base portion 70. The housing portion 1 and the base portion 70 can be assembled by engaging the housing-side claw portion 2 with the base-side claw portion 71 as shown in fig. 2B. That is, the housing portion 1 can be assembled with the base portion 70 using a snap fit. However, the manner of assembling the housing portion 1 to the base portion 70 is not limited to snap fit, and may be screw fastening, welding, bonding, or the like.

< Antenna 10>

The antenna 10 is an antenna for mobile communication, and is for example designed to handle radio waves used in the V2X (Vehicle to Everything: inter-vehicle communication, road-to-vehicle communication) band. However, the antenna 10 may be adapted to handle radio waves other than V2X radio waves, such as GNSS (Global Navigation SATELLITE SYSTEM), SXM (Sirius XM), ETC (Electronic Toll Collectionsystem, registered trademark), wi-Fi (registered trademark), and Bluetooth (registered trademark). The communication standard, polarized wave, and frequency band of the radio wave to be handled by the antenna 10 are not limited to the above, and may be other communication standard, polarized wave, and frequency band. That is, the antenna 10 can cope with a desired radio wave.

The antenna 10 is an antenna for handling radio waves of linearly polarized waves. For example, a linearly polarized wave may be referred to as a vertically polarized wave when the polarization plane is perpendicular to the earth, and a horizontally polarized wave when the polarization plane is horizontal to the earth. However, the antenna 10 may be an antenna that handles a radio wave of a circularly polarized wave. In the antenna device 100 of the present embodiment, the antenna 10 is a patch antenna. However, the antenna 10 may be a monopole antenna, a sleeve antenna, a dipole array antenna, a slot array antenna, or the like.

The antenna 10 is described in detail later.

< Adhesive part 30>

The adhesive portion 30 is a member for adhering the back surface of the antenna 10 to the front surface of the circuit board 40. In the antenna device 100 of the present embodiment, the adhesive portion 30 is a double-sided tape. However, the adhesive portion 30 may be an adhesive material other than double-sided tape. The adhesive portion 30 may be, for example, a nonconductive member or a conductive member. The conductive adhesive portion 30 is advantageous when the antenna 10C has the ground conductor 14, as in the antenna 10C of modification 1 shown in fig. 11A described later. As will be described in detail below.

< Circuit Board 40>

The circuit board 40 is a component formed of a conductor pattern. In the antenna device 100 of the present embodiment, the Circuit Board 40 is a Printed Circuit Board (PCB). In the antenna device 100 of the present embodiment, the circuit board 40 is a hard circuit board, but is not limited thereto, and may be a flexible circuit board. The circuit board 40 of the present embodiment is formed of a dielectric material, specifically, FR-4 (FLAME RETARDANT TYPE 4). However, the circuit board 40 may also be formed of teflon (registered trademark), PPE (Poly PHENYL ENEETHER), ceramic filler composites, PTFE (Poly Tetra Fluoro Ethylene), these composites.

The circuit board 40 may be provided with a circuit element such as a filter and an electronic element in addition to the conductor pattern. The circuit board 40 may be formed of one circuit board or may be formed of a plurality of circuit boards. The circuit board 40 may be formed by forming a conductive pattern on a resin material using MID (Molded Interconnect Device) technology.

As shown in fig. 3, the circuit board 40 is located on the-X direction side with respect to the antenna 10, and is bonded to the antenna 10 by the bonding portion 30.

The circuit board 40 has a conductor portion 41. The conductor portion 41 is a member functioning as a ground conductor film (or a ground conductor plate) in the antenna 10. The conductor portion 41 is disposed on the front surface side of the circuit board 40. As shown in fig. 3, the circuit board 40 is formed with a hole 42 through which the power feeding pin 16 (described below) is inserted, a hole 43 through which a power feeding side protruding portion 62 (described below) of the connector 60 is inserted, and a hole 44 through which a ground side protruding portion 63 (described below) of the connector 60 is inserted. The holes 42, 43, and 44 are formed as through holes, vias, and the like.

< Connector 60>

The connector 60 is a member for connecting the coaxial cable 6 to the circuit board 40 via the cable-side connector 64. The connector 60 is a member for outputting a signal to an external module (in the present embodiment, a device such as a V2X controller) not shown via the coaxial cable 6. As shown in fig. 1, the coaxial cable 6 is connected from the back surface side of the circuit board 40 by a connector 60.

The connector 60 has an interface portion 61, a power-feeding-side protruding portion 62, and a ground-side protruding portion 63.

The interface 61 is a portion to which a cable-side connector 64 attached to an end of the coaxial cable 6 is connected. As shown in fig. 2B, the interface portion 61 is located on the back side of the circuit board 40. Thereby, the coaxial cable 6 can be connected from the back surface side of the circuit board 40 via the cable-side connector 64.

The power feeding side protruding portion 62 is a member to which the signal line 7 of the coaxial cable 6 shown in fig. 1 is connected via the cable side connector 64. The power feeding side protruding portion 62 protrudes from the hole 43 formed in the circuit board 40 shown in fig. 3 to the surface side of the circuit board 40 as shown in fig. 4A and 4B. As shown in fig. 5B, the power feeding side protruding portion 62 is connected to the hole 42 through which the power feeding pin 16 of the antenna 10 is inserted, on the back surface side of the circuit board 40, through a power line (microstrip line) formed by the conductor portion 46.

The ground-side protruding portion 63 is a member to which the ground wire 8 of the coaxial cable 6 shown in fig. 1 is connected via the cable-side connector 64. The ground-side protruding portion 63 also protrudes from the hole 44 formed in the circuit board 40 shown in fig. 3 to the surface side of the circuit board 40 as shown in fig. 4A and 4B, in the same manner as the power-feeding-side protruding portion 62 described above. The ground-side protruding portion 63 is electrically connected to the conductor portion 41 on the front surface side of the circuit board 40 by soldering or the like, not shown.

As shown in fig. 5A and 5B, the connector 60 has a plurality of (four in the present embodiment) grounding side projections 63. The plurality of ground-side protrusions 63 are located around the power-feeding-side protrusion 62. In other words, the power feeding side protruding portion 62 is located at the center of the plurality of ground side protruding portions 63. However, the connector 60 may have only one grounding side projection 63. The ground-side protruding portion 63 may be formed in a cylindrical shape as positioned to surround the power-feeding-side protruding portion 62.

< Base portion 70>

The base portion 70 is a member that constitutes the exterior of the antenna device 100 together with the housing portion 1. In the antenna device 100 of the present embodiment, the base portion 70 is formed of a dielectric. Specifically, the base portion 70 is formed of an insulating resin such as ABS resin. However, the base portion 70 may be made of a material other than an insulating resin, which allows radio waves to penetrate. The base 70 may be made of an insulating resin portion and another material portion through which radio waves pass, or may be formed by freely combining components. As shown in fig. 3, the base portion 70 is located on the-X direction side of the antenna device 100.

The housing portion 1 and the base portion 70 together form an exterior of the antenna device 100, thereby forming a housing space therein. The antenna 10, the adhesive portion 30, the circuit board 40, and the connector 60 are accommodated in the accommodation space. However, a part of the connector 60 (a part of the interface 61 described later) is located outside the housing space from the opening of the base portion 70. As shown in fig. 5A, the base portion 70 is also a member for holding the circuit board 40.

As shown in fig. 3, the base portion 70 has a base-side claw portion 71, a guide 72, and a holding piece 73.

The base-side claw portion 71 is a portion engaged with the housing-side claw portion 2 of the housing portion 1. The housing portion 1 and the base portion 70 can be assembled by engaging the base-side claw portion 71 with the housing-side claw portion 2 as shown in fig. 2B.

The guide 72 is a portion for suppressing erroneous assembly of the circuit board 40 to the base portion 70 when the circuit board 40 is held by the base portion 70. As shown in fig. 3, the guide 72 protrudes toward the surface side of the base portion 70.

The number of guides 72 provided in the base portion 70 varies from side to side. Specifically, the base portion 70 has one guide 72 on the +y direction side, and has two guides 72 on the-Y direction side in the up-down direction. By disposing the guides 72 in different numbers in the left-right direction in this way, erroneous assembly of the circuit board 40 to the base portion 70 can be suppressed when the outer shape of the circuit board 40 is left-right, up-down, front-back, or symmetrical during rotation.

The holding piece 73 is a portion for holding the circuit board 40. The holding piece 73 is engaged with the end portion of the circuit board 40, whereby the circuit board 40 can be assembled with the base portion 70 as shown in fig. 5A. That is, the base portion 70 can use a snap fit to retain the circuit board 40. However, the manner in which the base portion 70 holds the circuit board 40 is not limited to snap-fit, and may be screw fastening, soldering, adhesive bonding, or the like.

As shown in fig. 5A, the holding piece 73 is located close to the conductor portion 41 of the circuit board 40. In the antenna device 100 of the present embodiment, the base portion 70 including the holding piece 73 is formed of a dielectric. Thus, even if the holding piece 73 is located in the vicinity of the conductor portion 41 of the circuit board 40, the influence on the antenna 10 due to the holding piece 73 can be suppressed. Further, the holding piece 73 is engaged with the end portion of the circuit board 40, whereby the circuit board 40 and the base portion 70 can be assembled, and workability can be improved.

Detailed of antenna 10

Next, referring again to fig. 1 to 6 described above, the antenna 10 will be described in detail.

The antenna 10 has a radiating element 11, a dielectric 12 and a feed pin 16.

The radiation element 11 is a conductive member to which the signal line 7 of the coaxial cable 6 is connected. As shown in fig. 3, the radiation element 11 is disposed on the surface of the dielectric 12. In the antenna device 100 of the present embodiment, the radiation element 11 is a planar conductive member. For example, the radiation element 11 is formed of a substantially quadrangular metal plate-like member (metal plate, sheet metal). Here, the "substantially quadrangular" means, for example, a shape including a square and a rectangle and formed of four sides, and may be, for example, a shape in which at least a part of the corners are cut obliquely to the sides. In the "substantially quadrangular" shape, a cut-in portion (concave portion) or a protruding portion (convex portion) may be formed in a part of the side. However, as will be described later, the planar conductive member may be a member formed of a conductor pattern.

However, the radiation element 11 is not limited to a substantially quadrangular shape, and may be formed of, for example, a circular shape and an elliptical shape. That is, the radiation element 11 may be of a shape that can make the antenna 10 cope with radio waves of a desired frequency band.

The radiating element 11 and the circuit board 40 are connected via the feed pin 16. As shown in fig. 4A, one end portion (+x-direction side end portion) of the power feeding pin 16 is connected to the radiating element 11, and the other end portion (-X-direction side end portion) is electrically connected to a conductor portion 46 (see fig. 5B for the conductor portion 46) formed on the back surface side of the circuit board 40.

Dielectric 12 is a component formed of a dielectric material. In the present embodiment, the dielectric 12 is formed of teflon (registered trademark), but may be formed of FR-4 (FLAME RETARDANT TYPE 4), PPE (Poly PhenylEneether), a ceramic filler composite material, PTFE (Poly Tetra Fluoro Ethylene), or a composite material of these materials.

The dielectric constant of teflon (registered trademark) used for the dielectric 12 of the present embodiment is about 2.6, and the dielectric constant of FR-4 used for the circuit board 40 is about 4.0. That is, in the present embodiment, the dielectric 12 and the circuit board 40 are each formed of a material having a different dielectric constant. However, for example, the dielectric 12 and the circuit board may be made of the same material, and the dielectric constant of the material used for the dielectric 12 and the dielectric constant of the material used for the circuit board 40 may be made the same.

The dielectric 12 has a substantially quadrangular shape in a plan view in the X direction. The shape of the dielectric 12 is not limited to a substantially quadrangular shape, and may be, for example, a circular shape, an elliptical shape, a polygonal shape, or the like. The dielectric 12 may be a dielectric plate or a solid or hollow resin member.

In the antenna 10 of the present embodiment, as shown in fig. 3, the radiation element 11 is disposed on the front surface side of the dielectric 12. However, the antenna 10 may be formed with a conductor pattern on a dielectric plate formed of resin or the like. In this case, the radiation element 11 is not a metal plate-like member (metal plate), but a conductor pattern portion on a dielectric plate, and the dielectric 12 is a resin portion of the dielectric plate.

As shown in fig. 3, holes 45 are formed at the end on the-Y direction side and the +z direction side and the end on the +y direction side and the-Z direction side as viewed from the front surface side of the dielectric 12. The hole 45 is a hole that is used as a positioning portion when the antenna 10 is manufactured. By manufacturing the antenna 10 with the hole 45 as a positioning portion, manufacturability can be improved. However, the hole 45 may not be formed in the dielectric 12.

As shown in fig. 6, a conductor 47 is formed on the rear surface side of the dielectric 12 in a region where the adhesive portion 30 (see fig. 3 for the adhesive portion 30) contacts. The conductor 47 is a conductor formed as a conductor pattern on the back surface side of the dielectric 12, and functions as a ground conductor film (or a ground conductor plate) in the antenna 10 together with the conductor 41 by capacitive coupling with the conductor 41 of the circuit board 40, as in the antenna 10C of modification 1 described later. By forming the conductor portion 47 on the rear surface side of the dielectric 12, the adhesion between the dielectric 12 and the adhesive portion 30 can be improved. However, the conductor portion 47 may not be formed on the back surface side of the dielectric 12, and in this case, the region where the adhesive portion 30 on the back surface side of the dielectric 12 is in contact may be subjected to a resist treatment.

In the antenna 10 of the present embodiment, the dielectric 12 has a housing portion 13. The housing portion 13 is a member for housing a component protruding on the front surface side of the circuit board 40. In the antenna device 100 of the present embodiment, the housing portion 13 is a recess having a substantially square shape in a plan view in the X direction, and houses the power feeding side protruding portion 62 and the plurality of ground side protruding portions 63 of the connector 60. However, the housing portion 13 may house only one of the power feeding side protruding portion 62 and the ground side protruding portion 63.

For example, in the case where the ground-side protruding portion 63 is shorter than the power-feeding-side protruding portion 62 (in the case where the size in the X direction is small), and in the case where only the power-feeding-side protruding portion 62 protrudes on the front surface side of the circuit board 40 (in the case where the connector 60 does not have the ground-side protruding portion 63), the housing portion 13 may house only the power-feeding-side protruding portion 62.

In the following description, the power feeding side protruding portion 62 and the ground side protruding portion 63 protruding on the front surface side of the circuit board 40, the electronic component disposed on the front surface side of the circuit board 40, and the like are sometimes simply referred to as "components". Furthermore, the element 65 may not be part of the connector 60, but part of the coaxial cable 6. That is, the signal line 7 and the ground line 8 may also form part of an element.

In this way, in the antenna device 100 of the present embodiment, the element is accommodated by the accommodation portion 13 of the dielectric 12, and the antenna device can be easily miniaturized. This is illustrated using a comparative example.

Comparative example

Fig. 7A is a perspective view of an antenna device 100A of comparative example 1. Fig. 7B is an explanatory diagram of the antenna 10A and the circuit board 40A of comparative example 1. Fig. 8 is an explanatory diagram of the antenna 10B and the circuit board 40B of comparative example 2.

< Comparative example 1>

As shown in fig. 7A, the antenna device 100A of comparative example 1 is connected to a coaxial cable 6, similarly to the antenna device 100 of the present embodiment. The antenna device 100A includes the antenna 10A and the circuit board 40A. In the antenna device 100A, the circuit board 40A is located on the back side of the antenna 10A, as in the antenna device 100 of the present embodiment.

The antenna 10A of comparative example 1 has a radiation element 11A and a dielectric 12A, as in the antenna 10 of the present embodiment. However, the housing portion 13 is not formed on the back surface of the dielectric 12A of the antenna 10A, as is the case with elements (for example, the power feeding side protruding portion 62) protruding on the front surface side of the circuit board 40A. Therefore, if the power-feeding-side protruding portion 62 is to be arranged in the area where the antenna 10A is arranged on the surface of the circuit board 40A, the antenna 10A (specifically, the dielectric 12A) and the power-feeding-side protruding portion 62 may interfere with each other. Therefore, in the antenna device 100A, it is difficult to dispose the power feeding side protruding portion 62 in the area where the antenna 10A is disposed in the surface of the circuit board 40A.

Accordingly, in the antenna device 100A, as shown in fig. 7B, the feeding-side protruding portion 62 is disposed in a region of the surface of the circuit board 40A where the antenna 10A is not disposed. In the antenna device 100A, it is necessary to secure a region for disposing the antenna 10A and the power-feeding-side protruding portion 62 independently on the surface of the circuit board 40A, and when compared with the antenna device 100 of the present embodiment, for example, the size of the circuit board 40A in the Y direction increases in the direction of the white arrow in fig. 7B. Accordingly, the antenna device 100A also has a larger size as compared with the antenna device 100 of the present embodiment.

< Comparative example 2>

As shown in fig. 8, the antenna device 100B of comparative example 2 is also connected to a coaxial cable 6, similarly to the antenna device 100 of the present embodiment. The antenna device 100B includes the antenna 10B and the circuit board 40B. In the antenna device 100B, the circuit board 40B is located on the back side of the antenna 10B, as in the antenna device 100 of the present embodiment.

The antenna 10B has a radiation element 11B and a dielectric 12B, similarly to the antenna 10 in the present embodiment. In addition, the housing portion 13 is not formed on the back surface of the dielectric 12B of the antenna 10B, as is the case with elements (for example, the power feeding side protruding portion 62) protruding on the front surface side of the circuit board 40B. In the antenna device 100B, the feed-side protruding portion 62 is disposed in a region where the antenna 10B is disposed in the surface of the circuit board 40B. However, in the antenna device 100B, as shown in fig. 8, in order to suppress interference between the antenna 10B (specifically, the dielectric 12B) and the feeding-side protruding portion 62, a gap 66 is formed between the antenna 10B and the circuit board 40B in the X direction. A spacer may be disposed between the antenna 10B and the circuit board 40B.

However, when the antenna device 100B is compared with the antenna device 100 of the present embodiment, for example, the size of the entire antenna device in the X direction increases in the direction of the white arrow in fig. 8.

In the antenna device 100 of the present embodiment, compared with the antenna device 100A of the 1 st comparative example and the antenna device 100B of the 2 nd comparative example, the dielectric 12 has the housing portion 13 for housing the element protruding on the front surface side of the circuit board 40, and thus, miniaturization can be easily achieved.

The dielectric 12 of the present embodiment has a storage portion 13 to change the dielectric constant as compared with dielectrics having no storage portion (for example, the dielectric 12A of comparative example 1 and the dielectric 12B of comparative example 2). Specifically, the dielectric 12 of the present embodiment has a smaller dielectric constant than a dielectric having no accommodating portion. This is because, in the case of a dielectric having no storage portion, a predetermined portion occupied by the dielectric material becomes a space (air) partitioned by the storage portion 13. That is, the dielectric 12 of the present embodiment has a dielectric constant smaller than that of a dielectric without the housing portion, considering the dielectric constant of air with respect to the space partitioned by the housing portion 13.

< Nodule >

The antenna device 100 according to the present embodiment is summarized below with reference to fig. 9.

Fig. 9 is an explanatory diagram of the antenna device 100 according to embodiment 1. Fig. 9 shows a simplified cross-sectional configuration of the antenna device 100. Hereinafter, the structure of the antenna 10 according to the present embodiment corresponding to the dielectric 12 will be described as "1 st base", and the structure corresponding to the circuit board 40 will be described as "2 nd base".

The antenna device 100 of embodiment 1 has a1 st base and a2 nd base. The 1 st base has a1 st face 18 where the radiation element 11 is located and a2 nd face 19 opposite to the 1 st face 18, and the 2 nd base has a3 rd face 48 facing the 2 nd face 19 of the 1 st base and a4 th face 49 opposite to the 3 rd face 48.

Here, the 1 st surface 18 corresponds to the surface of the dielectric 12, the 2 nd surface 19 corresponds to the back surface of the dielectric 12, the 3 rd surface 48 corresponds to the surface of the circuit board 40, and the 4 th surface 49 corresponds to the back surface of the circuit board 40.

Further, the element 65 is disposed on the 3 rd surface 48 of the 2 nd base portion. Here, the element 65 corresponds to the power feeding side protruding portion 62 and the ground side protruding portion 63 protruding on the surface side of the circuit board 40, the electronic element disposed on the surface side of the circuit board 40, a part of the signal line 7 and the ground line 8, and the like. The 1 st base has a housing portion 13 which houses the element 65 and is formed of a dielectric. In the antenna device 100 of the present embodiment, the "housing portion 13 formed of a dielectric" is a portion of the dielectric 12 surrounding a recess formed in the dielectric 12. Further, the housing portion 13 is integrally formed with a portion of the dielectric 12 other than the housing portion 13, and thus, in fig. 9, a boundary between the housing portion 13 and the portion other than the housing portion 13 is appropriately indicated by a broken line.

Characteristic(s)

Fig. 10 is a diagram showing an example of directivity of the antenna 10 in embodiment 1.

Fig. 10 shows an example of the radiation pattern of the antenna 10 according to embodiment 1 in the horizontal plane (XY plane) by a broken line. In fig. 10, an example of the radiation pattern of the antennas of the comparative example (for example, the antennas 10A and 10B of the 1 st and 2 nd comparative examples described above) having no receiving portion is indicated by a dotted line.

As shown in fig. 10, the maximum gain of directivity in the horizontal plane of the antenna 10 in embodiment 1 is 5.8dBi, and the maximum gain of directivity in the horizontal plane of the antenna of the comparative example is 5.8dBi. Therefore, it is understood that the antenna 10 in embodiment 1 has the same characteristics as those of the antenna of the comparative example. That is, in the antenna device 100 according to embodiment 1, interference between the antenna 10 and the element 65 can be suppressed, and miniaturization of the antenna device can be easily achieved while maintaining the characteristics of the antenna 10.

In the antenna 10 of embodiment 1, the electrical length in the vertical direction of the radiating element 11 disposed in the dielectric 12 is approximately one half of the wavelength of the radio wave band (here, the band used for V2X) to be handled by the antenna 10. In other words, the frequency band of the radio wave to be handled by the antenna 10 is almost determined by the electrical length of the radiating element 11 disposed in the dielectric 12 in the vertical direction. In the antenna 10 of embodiment 1, the receiving portion 13 serving as a recess is formed on the rear surface side of the dielectric 12, but even if the receiving portion 13 is not formed (that is, even if the same as the dielectric of the antenna of the comparative example is formed), the shape of the radiating element 11 is not substantially changed.

That is, in the antenna 10 according to embodiment 1, the shape of the radiation element 11 is substantially the same as that of the antenna according to the comparative example, and thus the frequency band and/or impedance of the radio wave to be handled by the antenna 10 may be finely adjusted only by changing the thickness of a part of the dielectric 12. Therefore, the antenna 10 according to embodiment 1 can easily secure a gain of directivity equivalent to that of the antenna of the comparative example. However, as the volume of the housing portion 13 becomes larger, the radiation efficiency of the antenna 10 gradually decreases, and thus, it is desirable that the volume of the housing portion 13 is as small as possible.

Modification example

Fig. 11A is a perspective view of an antenna 10C according to modification 1. Fig. 11B is a perspective view of the antenna 10C of modification 1, which is seen from another angle. Fig. 12 is a perspective view of an antenna 10D according to modification 2.

< Modification 1>

The antenna 10C of modification 1 includes a radiating element 11C, a dielectric 12C, a ground conductor 14, and a non-feeding element 17. The radiation element 11C and the dielectric 12C are the same as the radiation element 11 and the dielectric 12 of the antenna 10 in the present embodiment described above. The dielectric 12C has a housing portion 13C for housing the element 65.

In the antenna 10C, as shown in fig. 11A, a ground conductor 14 is disposed on the rear surface side of the dielectric 12C. The ground conductor 14 is a member that functions as a ground conductor film (or a ground conductor plate) in the antenna 10C together with the conductor portion 41 (not shown in fig. 11A and 11B) of the circuit board 40. The dielectric 12C of the antenna 10C and the circuit board 40 are bonded using the bonding portion 30.

In the antenna 10C according to modification 1, even if the conductor portion 41 of the circuit board 40 and the ground conductor 14 are not connected by a conductor or the like, the ground conductor 14 of the antenna 10C and the conductor portion 41 of the circuit board 40 are electrically connected by capacitive coupling by bringing the dielectric 12C and the circuit board 40 into proximity. This makes it possible to use the conductor portion 41 of the circuit board 40 as a ground conductor film (or ground conductor plate). Therefore, the region of the portion functioning as the ground conductor film (or the ground conductor plate) can be enlarged, and the directional characteristic can be easily oriented in a desired direction (forward in the present embodiment). In addition, the size of the antenna device can be reduced.

As shown in fig. 11A, the ground conductor 14 is not formed in the region where the housing portion 13C is formed. Therefore, if the conductor portion 41 of the circuit board 40 and the ground conductor 14 are not connected by a conductor or the like, a distance is generated between the conductor portion 41 of the circuit board 40 and the radiating element 11C, and the characteristics of the antenna 10C are affected. Accordingly, the conductor 41 and the ground conductor 14 may be electrically connected by a conductive member. Specifically, the antenna 10C and the circuit board 40 are bonded by the conductive bonding portion 30. This can improve the characteristics of the antenna 10C.

As shown in fig. 11B, the power feeding element 17 is disposed on the front surface side of the dielectric 12C. The non-feeding element 17 is a rectangular conductor portion along the left and right sides of the radiating element 11C. By disposing the feeding element 17, the gain of the antenna 10C can be improved. Specifically, by disposing the non-feeding element 17 on the dielectric 12C, the half-value angle of the horizontal plane of the antenna 10C is enlarged, and the gain in the Y direction is improved.

In the antenna 10C of modification 1, as shown in fig. 11B, a pair of non-feeding elements 17 is arranged so as to be separated from the center of the radiating element 11C in the Y direction. That is, the pair of non-feeding elements 17 are opposed to each other across the radiating element 11C. The surfaces of the pair of non-feeding elements 17 may be located on the same plane as the surface (that is, the radiation surface) of the radiation element 11C, or may be located at a position apart in the X direction with respect to the surface of the radiation element 11C. At least one of the pair of non-feeding elements 17 may not be located on the surface of the dielectric 12C, or may be located at a position away from the dielectric 12C in the X direction. Further, a ground conductor may be arranged on the-X direction side of the non-feeding element 17. However, the ground conductor may not be disposed so as to face the non-feeding element 17.

The antenna 10C may have one feeding-free element 17 instead of a pair of feeding-free elements 17. For example, in the antenna 10C, one non-feeding element 17 may be disposed on the +y direction side of the radiating element 11C. This makes it possible to bias the directivity of the antenna 10C toward a desired direction. That is, by setting the non-feeding element 17 to a desired arrangement, the directivity of the antenna 10C can be easily controlled.

In the antenna 10C, the lengths and widths of the respective pair of non-feeding elements 17 are the same. However, the respective lengths and widths of the pair of non-feeding elements 17 may be different from each other. In the antenna 10C, the pair of non-feeding elements 17 are arranged symmetrically (here, line symmetry and point symmetry) with respect to the center of the radiating element 11C. Here, the center of the radiation element 11C refers to the geometric center of the radiation element 11C when viewed in the X direction. The pair of non-feeding elements 17 are disposed so that the distance from the outer edge of the radiating element 11C is the same. However, the pair of non-feeding elements 17 may be configured not to be symmetrical with respect to the center of the radiating element 11C. This makes it possible to bias the directivity of the antenna 10C toward a desired direction. That is, by setting the non-feeding element 17 to a desired arrangement, the directivity of the antenna 10C can be easily controlled. For example, when the antenna device having the antenna 10C is disposed in a corner of a vehicle, the desired characteristics of the antenna 10C can be easily adjusted by shifting the range of directivity of the antenna 10C.

Although detailed characteristic verification is omitted, in modification 1, interference between the antenna 10C and the element 65 can be suppressed, and miniaturization of the antenna device can be easily achieved while maintaining the characteristics of the antenna 10C.

< Modification example 2>

In the antenna 10 according to the present embodiment described above, the shape of the housing portion 13 is substantially a quadrangular shape in plan view. However, the shape of the housing portion 13 is not limited thereto. In the antenna 10D according to modification 2, as shown in fig. 12, the housing portion 13D has a circular shape in a plan view. As described above, the frequency band of the radio wave to be handled by the antenna 10 is determined almost by the electrical length in the vertical direction of the radiating element 11 disposed in the dielectric 12.

Therefore, even if the shape of the housing portion 13 is changed, the influence on the shape of the radiation element of the antenna 10D is small. Therefore, the frequency band and impedance of the radio wave to be handled by the antenna 10D may be finely adjusted, regardless of the shape of the housing portion 13. Therefore, although detailed characteristic verification is omitted, the antenna 10D of modification 2 can ensure a gain in directivity equivalent to that of the antenna 10 of the present embodiment. That is, in modification 2 as well, interference between the antenna 10D and the element 65 can be suppressed, and miniaturization of the antenna device can be easily achieved while maintaining the characteristics of the antenna 10D.

= Embodiment 2=

Fig. 13 is an explanatory diagram of an antenna device 100E according to embodiment 2.

In the antenna device 100 according to embodiment 1, the housing portion 13 includes a recess formed in the dielectric 12. That is, the housing portion 13 is integrally formed with a portion of the dielectric 12 other than the housing portion 13. However, the housing portion may be a portion (independent body) formed independently of the dielectric. In the antenna device 100E according to embodiment 2, as shown in fig. 13, the housing portion 13E is formed as a box-shaped member that opens in the-Y direction. The storage portion 13E is formed of a dielectric material in the same manner as the storage portion 13.

Although detailed characteristic verification is omitted, in the antenna device 100E of embodiment 2, interference between the antenna 10E and the element 65E can be suppressed, and miniaturization of the antenna device can be easily achieved while maintaining the characteristics of the antenna 10E.

= 3 Rd embodiment= =

Fig. 14 is an explanatory diagram of an antenna device 100F according to embodiment 3. Fig. 15A is a perspective view of antenna 10F according to embodiment 3. Fig. 15B is a perspective view of antenna 10F of embodiment 3 viewed from another angle.

In the antenna 10 according to embodiment 1, a recess is formed in the housing portion 13 so as to open the rear surface of the dielectric 12. In the antenna 10F of embodiment 3, as shown in fig. 14, a through hole 15 is formed to penetrate from the front surface to the back surface of the dielectric 12F. Therefore, in the antenna 10F according to embodiment 3, the "housing portion 13F formed of a dielectric" is a portion of the dielectric 12F surrounding the through-hole 15 formed in the dielectric 12F. Note that, the storage portion 13F is integrally formed with a portion of the dielectric 12F other than the storage portion 13F, and thus, in fig. 14, a boundary between the storage portion 13F and the portion other than the storage portion 13F is appropriately indicated by a broken line.

The storage portion 13F does not require adjustment of the depth of the recess as compared with the storage portion 13 having the recess formed therein, and the burr treatment of the machined surface is not required, so that machining and management can be easily performed and the cost can be reduced.

In the antenna device 100F according to embodiment 3, as shown in fig. 15A and 15B, a plurality of through holes 15 are formed in the dielectric 12F. The plurality of through holes 15 overlap the planar radiating element 11F in a plan view. That is, a plurality of through holes 15 are formed on the radiation element 11F. However, a part of the plurality of through holes 15 may not be formed in the radiation element 11F, or none of the plurality of through holes 15 may be formed in the radiation element 11F.

The plurality of through holes 15 are located near the center of the radiating element 11F and are located at positions where the feed pins do not interfere (that is, at positions of the holes 20). However, the through-hole 15 may overlap with the feed pin (that is, the position of the hole 20) as long as the feed pin is disposed in a region that does not interfere with the element 65 located on the surface of the circuit board 40F and can be connected to the radiation element 11F.

Although detailed characteristic verification is omitted, in the antenna device 100F of embodiment 3, interference between the antenna 10F and the element 65F can be suppressed, and miniaturization of the antenna device can be easily achieved while maintaining the characteristics of the antenna 10F.

While the embodiments and the modifications of the present invention have been described above with reference to the drawings, these are examples of the present invention, and various configurations other than the above can be adopted.

= Summary=

According to the present specification, an antenna device in the following manner is provided.

(Mode 1)

The antenna device according to embodiment 1 includes a 1 st base portion having a 1 st surface 18 where the radiation element 11 is located and a2 nd surface 19 opposite to the 1 st surface 18, and a2 nd base portion having a3 rd surface 48 opposite to the 2 nd surface 19 of the 1 st base portion and a 4 rd surface 49 opposite to the 3 rd surface 48, wherein the element 65 is disposed on the 3 rd surface 48 of the 2 nd base portion, and the 1 st base portion includes a housing portion 13 which houses the element 65 and is formed of a dielectric.

According to the above-described aspect, the antenna device 100 can be easily miniaturized.

(Mode 2)

In embodiment 2, the signal line 7 and the ground line 8 of the coaxial cable 6 are electrically connected to the element 65.

According to the above-described aspect, the antenna device 100 can be easily miniaturized.

(Mode 3)

In embodiment 3, the conductor portion 41 connected to the ground line 8 is formed on the 3 rd surface 48 of the 2 nd base portion, and the adhesive portion 30 for adhering the 2 nd surface 19 of the 1 st base portion to the 3 rd surface 48 of the 2 nd base portion is provided.

According to the above aspect, the 1 st base and the 2 nd base can be bonded.

(Mode 4)

In embodiment 4, a conductor portion 41 connected to the ground line 8 is formed on the 3 rd surface 48 of the 2 nd base portion, and the ground conductors 14 are formed on the 1 st and 2 nd base portions, and the conductor portion 41 is electrically connected to the ground conductors 14.

According to the above aspect, the characteristics of the antenna can be improved.

(Mode 5)

In embodiment 5, the ground conductor 14 of the 1 st base and the conductor 41 of the 2 nd base are electrically connected by a conductive member or are disposed in close proximity by capacitive coupling.

According to the above aspect, the characteristics of the antenna can be improved.

(Mode 6)

In embodiment 6, a recess for opening the 2 nd surface 19 is formed in the housing portion 13.

According to the above-described aspect, the antenna device 100 can be easily miniaturized.

(Mode 7)

In embodiment 7, a through hole 15 penetrating from the 1 st surface 18 to the 2 nd surface 19 is formed in the housing portion 13.

According to the above-described aspect, the antenna device 100 can be easily miniaturized.

(Mode 8)

In embodiment 8, the radiation element 11 is a planar radiation element, and the planar radiation element 11 overlaps with the plurality of through holes in a plan view.

According to the above aspect, the antenna device 100 can be easily miniaturized.

(Mode 9)

In embodiment 9, a base portion 70 formed of a dielectric material and holding the 2 nd base portion is further provided, and the base portion 70 includes a holding piece 73 that holds the 2 nd base portion by engaging with an end portion of the 2 nd base portion.

According to the above-described aspect, the influence on the antenna 10 caused by the holding piece 73 can be suppressed.

(Mode 10)

In mode 10, the radiation element 11 is configured to cope with linearly polarized waves.

According to the above-described aspect, the antenna device 100 can be easily miniaturized.

The above embodiments are for easy understanding of the present invention and are not intended to limit the present invention. The present invention is not limited to the above-described embodiments, and may be modified or improved without departing from the spirit thereof.

Description of the reference numerals

6 Coaxial cable

7 Signal line

8 Ground wire

11. 11A-11C, 11E, 11F radiation element

12. 12A-12F dielectric

13. 13C-13F storage part

14. 14D, 14F ground conductors

15 Through holes

18 1 St side

19 Nd surface 2

30 Adhesive part

46 Conductor part

48 3 Rd surface

49 Th surface 4

60 Connector

65. 65E, 65F element

70 Base portion

73 Holding sheet

100. 100A, 100B, 100E, 100F antenna arrangement.

Claims (10)

1. An antenna device, comprising: A first base having a first surface on which the radiation element is located, and a second surface opposite to the first surface; and a second base having a third surface facing the second surface of the first base and a fourth surface opposite to the third surface, An element is arranged on the third surface of the second base, The first base portion includes a housing portion that houses the element and is formed of a dielectric. 2. The antenna device according to claim 1, wherein: The signal line and the ground line of the coaxial cable are electrically connected to the element. 3. The antenna device according to claim 2, wherein: A conductor portion connected to the ground line is formed on the third surface of the second base portion. The device includes an adhesive portion for bonding the second surface of the first base portion and the third surface of the second base portion. 4. The antenna device according to claim 2, wherein: A conductor portion connected to the ground line is formed on the third surface of the second base portion. A ground conductor is formed on the second surface of the first base portion, The conductor portion is electrically connected to the ground conductor. 5. The antenna device according to claim 4, wherein: The ground conductor of the first base portion and the conductor portion of the second base portion are electrically connected via a conductive member or are disposed in close proximity to each other in a capacitive coupling manner. 6. The antenna device according to any one of claims 1 to 5, wherein: The housing portion includes a recessed portion that opens the second surface. 7. The antenna device according to any one of claims 1 to 5, wherein: The housing portion has a through hole formed therein that passes through from the first surface to the second surface. 8. The antenna device according to claim 7, wherein: The radiation element is a planar radiation element. When viewed from above, the planar radiation element overlaps with the plurality of through holes. 9. The antenna device according to any one of claims 1 to 8, wherein: It also has a base portion formed of a dielectric and holding the second base portion, The base portion includes a holding piece that holds the second base portion by engaging with an end portion of the second base portion. 10. The antenna device according to any one of claims 1 to 9, wherein: The radiating element is responsive to linearly polarized waves.