JP6639933B2 - In-vehicle antenna device - Google Patents

Description

  The present invention relates to an on-vehicle antenna device arranged at an end of a roof of a vehicle body.

  With the expansion of wireless communication applications, in addition to antennas operating in frequency bands such as FM / AM broadcasting and digital terrestrial broadcasting that have been used in the past, 3G (3rd Generation: 3rd generation mobile phones) and LTE (Long Antennas operating in higher frequency bands, such as Term Evolution, are mounted on automobiles.

  When these antennas are mounted on an automobile, a method of attaching the antenna itself to a window glass or the like and a method of attaching a vehicle-mounted antenna device incorporating the antenna to a roof or the like have been adopted. When adopting the latter method, it is important to make the vehicle-mounted antenna device as unobtrusive as possible in order to enhance the aesthetic appearance of the vehicle.

  For example, Patent Literature 1 discloses a vehicle-mounted antenna device having a spoiler as a housing. As shown in FIG. 5 of Patent Document 1, this on-vehicle antenna device has a digital TV antenna and a radio antenna built inside a spoiler arranged at a rear end of a roof of a vehicle body. is there. In this vehicle-mounted antenna device, the radiating element of the digital television antenna and the radiating element of the radio antenna are built in the spoiler so as to be horizontal when the spoiler is mounted on the vehicle body.

JP 2008-283609 A (published November 20, 2008)

  However, the antenna structure of the vehicle-mounted antenna device described in Patent Literature 1 has a problem that the radiation gain toward the front of the vehicle body is small.

  That is, in the vehicle-mounted antenna device described in Patent Literature 1, a configuration in which the radiating elements constituting the antenna are horizontally arranged is adopted. For this reason, the electromagnetic wave radiated from the vehicle-mounted antenna device described in Patent Document 1 is an electromagnetic wave having horizontal polarization as a main polarization component. The horizontally polarized waves emitted from the vehicle-mounted antenna device disposed at the rear end of the roof toward the front end of the roof are attenuated in the process of traversing the roof, which is a metal body extending parallel to the plane of polarization. . Therefore, in the in-vehicle antenna device described in Patent Literature 1, there is a problem that the radiation gain forward of the vehicle body is reduced.

  Further, the attenuation effect by the roof becomes more remarkable as the wavelength of the electromagnetic wave radiated by the antenna becomes shorter. This is because the shorter the wavelength of the electromagnetic wave, the more difficult it is for diffraction to occur. In recent years, the amount of information transmitted using wireless communication has been increasing steadily, and the wavelength of electromagnetic waves used for wireless communication tends to be shortened. For example, since the wavelength of an electromagnetic wave conforming to the LTE standard is shorter than the wavelength of an electromagnetic wave used for transmission of FM / AM broadcast, it is more likely to be affected by the attenuation effect of the roof. In the case of an antenna system that receives electromagnetic waves transmitted from the zenith direction, such as a GPS (Global Positioning System), the attenuation effect of the electromagnetic waves by the roof can be ignored. However, in the case of an antenna system such as 3G or LTE which requires communication with a base station installed on the ground, the gain reduction due to the attenuation effect by the roof is a serious problem and cannot be ignored.

  Here, the problem that occurs when the in-vehicle antenna device is arranged at the rear end of the roof has been described. However, the same problem occurs when the in-vehicle antenna device is arranged at the front end, right end, or left end of the roof. . That is, when the in-vehicle antenna device is disposed at the front end of the roof, there is a problem that the radiation gain toward the rear of the vehicle body is reduced. There is a problem that the radiation gain to the right / right side is reduced. That is, in any case, there is a problem that the radiation gain in the direction crossing the roof as viewed from the vehicle-mounted antenna device is reduced.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an in-vehicle antenna device in which when mounted on an end of a roof of a vehicle body, a radiation gain in a direction traversing the roof is larger than before. It is to realize.

  In order to solve the above problem, an in-vehicle antenna device according to one embodiment of the present invention is an in-vehicle antenna device arranged at an end of a roof of a vehicle body, the first to third power supply points being a pair of power supply points. An antenna having a radiating element including a first radiating element drawn in one direction and a second radiating element drawn in a second direction different from the first direction from the other feeding point, or A single radiating element that is drawn out of one of the pair of feeding points in a first direction and drawn out of the other feeding point in a second direction different from the first direction. An antenna, wherein the first direction is a direction crossing a horizontal plane when the vehicle-mounted antenna device is mounted on the vehicle body.

  According to the above configuration, the first direction in which the radiating element is pulled out from one of the feeding points is a direction crossing a horizontal plane (for example, a direction orthogonal to the horizontal plane) when the vehicle-mounted antenna device is mounted on the vehicle body. Therefore, the ratio of the vertically polarized wave component included in the radiated electromagnetic wave can be made larger than that of the related art (the in-vehicle antenna device described in Patent Document 1).

  Vertically polarized waves are less likely to be attenuated by the roof than horizontal polarized waves. Therefore, according to the above configuration, it is possible to realize a vehicle-mounted antenna device having a radiation gain in a direction crossing the roof larger than that of the related art. For example, when this in-vehicle antenna device is arranged at the rear end of the roof, it is possible to realize an in-vehicle antenna device having a larger radiation gain to the front of the vehicle body than before.

  In the radiating element, a section including one feeding point may be drawn in the first direction, and a section including the other feeding point may be drawn in the second direction. The extending direction of the radiating element is not particularly limited. For example, when the antenna is a dipole antenna, the starting end of the first radiating element including one feeding point is drawn out in the first direction, and the starting end of the second radiating element including the other feeding point is set to the first end. 2, the extension direction of the terminal portion of the first radiating element and the extending direction of the terminal portion of the second radiating element are arbitrary. For example, (1) a configuration in which both the end portion of the first radiating element and the end portion of the second radiating element extend forward of the vehicle body (see first and third embodiments described later), (2) A configuration in which the terminal end of the first radiating element extends rightward of the vehicle body, and the terminal end of the second radiating element extends leftward of the vehicle body (see a second embodiment described later). (3) First radiation A configuration in which the terminal end of the element extends forward of the vehicle body and the terminal end of the second radiating element extends rearward of the vehicle body (refer to a fourth embodiment described later) or the like can be considered.

  In the vehicle-mounted antenna device according to one embodiment of the present invention, it is preferable that the second direction intersects the horizontal plane when the vehicle-mounted antenna device is mounted on the vehicle body.

  According to the above configuration, it is possible to further increase the ratio of the vertically polarized component included in the radiated electromagnetic wave.

  In the vehicle-mounted antenna device according to one aspect of the present invention, it is preferable that the second direction is a direction along the horizontal plane when the vehicle-mounted antenna device is mounted on the vehicle body.

  According to the above configuration, it is possible to radiate an electromagnetic wave including both the vertical polarization component and the horizontal polarization component.

  In the vehicle-mounted antenna device according to one aspect of the present invention, the radiating element further includes a superimposing portion that overlaps with a metal member that constitutes the end of the roof and that is separated from the metal member. Preferably, it is provided.

  According to the above configuration, the roof, which is a metal member, can be used as the ground of the radiating element. Thereby, the radiation gain in the direction crossing the vehicle body can be increased.

  In the on-vehicle antenna device according to one aspect of the present invention, a width of a portion of the radiating element that is drawn from the one feeding point in the first direction is １ ／ of a shortest wavelength of an electromagnetic wave radiated by the antenna. The following is preferable.

  According to the above configuration, the direction of the current flowing through the radiating element in the vicinity of the one feeding point can be restricted to the first direction. Therefore, it is possible to realize an in-vehicle antenna device in which the radiation gain in the direction traversing the roof is even larger than before.

  In the vehicle-mounted antenna device according to one aspect of the present invention, the width of a portion of the radiating element that is drawn in the first direction from the one feeding point, and the width of the radiating element from the other feeding point. It is preferable that at least one of the widths of the portion drawn in the second direction is equal to or less than の of the shortest wavelength of the electromagnetic wave radiated by the antenna.

  According to the above configuration, when the in-vehicle antenna device is mounted on the vehicle body, the first direction is a direction intersecting the roof, the second direction is a direction intersecting the roof, and the first direction is a direction intersecting the roof. When a configuration that is different from the direction is adopted, the direction of the current flowing through the radiating element is restricted to the first direction in at least one of the vicinity of one of the feeding points and the vicinity of the other feeding point. be able to. Therefore, it is possible to realize an in-vehicle antenna device in which the radiation gain in the direction traversing the roof is even larger than before.

  In the on-vehicle antenna device according to one embodiment of the present invention, the antenna is preferably a dipole antenna.

  According to the above configuration, in a vehicle-mounted antenna device having a built-in dipole antenna, it is possible to realize a vehicle-mounted antenna device having a larger radiation gain in a direction crossing the roof than in the related art.

  The in-vehicle antenna device according to one aspect of the present invention is arranged at the front end or the rear end of the roof, and the width of the radiating element measured along the front end or the rear end of the roof is It is preferable that the wavelength is equal to or less than 1/2 of the shortest wavelength of the electromagnetic wave radiated by the antenna.

  According to the above configuration, the direction of the main current flowing through the radiating element can be limited to the front-back direction of the vehicle body. Therefore, it is possible to suppress the effect that the radiating element is attached to the front glass or the rear glass of the vehicle body and gives to the other antenna extending in the left-right direction of the vehicle body, or the influence of the other antenna.

In the in-vehicle antenna device according to one embodiment of the present invention, the first radiating element is disposed on a first portion intersecting the horizontal plane and on a second surface intersecting the first surface. And a second part to be
Preferably, the second radiating element is arranged along the horizontal plane and on a third surface facing the second surface.

  According to the above configuration, since the radiating element can be bent into a U-shape, the volume of the space required for disposing the radiating element can be reduced. Therefore, a smaller vehicle-mounted antenna device can be realized as compared to a case where the radiating element is not bent.

  In the in-vehicle antenna device according to one embodiment of the present invention, it is preferable that the second radiating element has a shape in which a notch or a concave shape is formed with respect to a long side of the rectangle.

  By forming a notch or a concave shape with respect to the long side of the second radiating element which is rectangular, the length of a contour (referred to as a long edge) corresponding to the long side of the second radiating element can be reduced. It can be secured for a long time. Thereby, for example, the length of the long edge corresponding to the band on the low frequency side of the operating band of the vehicle-mounted antenna device can be secured. Therefore, according to the above configuration, the operating band of the antenna can be effectively expanded particularly to the low frequency side.

In the in-vehicle antenna device according to one embodiment of the present invention, the one feeding point is located on the third surface and near an intersection with the first surface.
When the radiating element is viewed in a plan view from a direction orthogonal to the third surface, it is preferable that the one feeding point and the second portion do not overlap.

  According to the above configuration, since the second portion of the first radiating element is configured not to overlap the feed point (one feed point) of the first radiating element, in the first radiating element, The capacitance formed between the second portion and the feeding point can be suppressed. As a result, it is possible to suppress deterioration of radiation characteristics caused by bending the antenna from a state where the antenna is developed on a plane.

  It is preferable that the in-vehicle antenna device according to one embodiment of the present invention has a spoiler as a housing.

  According to the above configuration, it is possible to realize an in-vehicle antenna device having a larger radiation gain toward the front of the vehicle body than before, without impairing the appearance and aerodynamic characteristics of the vehicle body.

  According to the present invention, it is possible to realize an in-vehicle antenna device in which the radiation gain in a direction crossing the roof is larger than in the related art.

(A) is a perspective view showing the appearance of a vehicle body on which the vehicle-mounted antenna device according to the first embodiment of the present invention is mounted, and (b) is a part of the vehicle body on which the vehicle-mounted antenna device is mounted. It is an enlarged plan view. 1A is an enlarged cross-sectional view of a part of the vehicle body on which the on-vehicle antenna device is mounted, and is a cross-sectional view taken along line AA ′ shown in FIG. . (B) is a development view of an antenna provided in the vehicle-mounted antenna device. (A) is a partially enlarged plan view of a vehicle body on which the vehicle-mounted antenna device according to the second embodiment is mounted. FIG. 2B is an enlarged cross-sectional view of a part of the vehicle body on which the vehicle-mounted antenna device is mounted, and is a cross-sectional view taken along line L-L ′ shown in FIG. (A) is an arrow cross-sectional view of a vehicle body on which a vehicle-mounted antenna device according to a third embodiment of the present invention is mounted. (B) is a development view of an antenna provided in the vehicle-mounted antenna device. (A) is the arrow sectional view which expanded a part of vehicle body which mounts the vehicle-mounted antenna apparatus which concerns on 4th Embodiment. (B) is a development view of an antenna provided in the vehicle-mounted antenna device. (A) is a development view of an antenna according to a first modification of the present invention, and (b) is a side view of the antenna as viewed from an arrow. (C) is a development view of an antenna according to a second modification of the present invention, and (d) is a side view of the antenna as viewed from an arrow. It is a development view of the antenna concerning the 3rd modification. It is a development view of another antenna concerning a 3rd modification. It is a development view of the antenna concerning the 4th modification. 5 is a graph showing the direction dependency of the radiation gain in the xy plane obtained by the on-vehicle antenna device according to the first embodiment. 9 is a graph showing the direction dependence of the radiation gain in the xy plane obtained by the vehicle-mounted antenna device according to the second embodiment. 11 is a graph showing the direction dependence of the radiation gain in the xy plane obtained by the vehicle-mounted antenna device according to the third embodiment. It is a graph which shows S21 obtained by the in-vehicle antenna device concerning a 4th example. FIG. 9 is an enlarged cross-sectional view taken along line A-A ′ of FIG. 1B, in which a part of a vehicle body on which a vehicle-mounted antenna device according to a fifth embodiment is mounted is enlarged. FIG. 15 is a development view in which two types of antennas included in the vehicle-mounted antenna device shown in FIG. 14 are developed on a plane. In each of the second radiating elements constituting the two types of antennas shown in FIG. 15, the shapes of two edges connecting the feeding point and the corners of the radiating elements that are separated from the feeding point in the longitudinal direction are indicated by broken lines and It is explanatory drawing shown with a dashed-dotted line. (A)-(c) is a development view in which the antennas included in the antenna devices according to the fifth to seventh embodiments are respectively developed on a plane. (A) is a graph which shows the frequency dependence of the radiation gain of the antenna device which concerns on 5th-6th Example. (B) is a graph showing the frequency dependence of the VSWR of the antenna device according to the fifth to sixth embodiments. (A) is a graph which shows the frequency dependence of the radiation gain of the antenna device which concerns on the 6th-7th Example. (B) is a graph which shows the frequency dependence of VSWR of the antenna devices according to the sixth and seventh embodiments. FIG. 9 is a development view in which a modification of the antenna shown in FIG. 7 is developed on a plane. (A) is a top view of the antenna shown in FIG. (B) is a right side view of the antenna. (C) is a sectional arrow view of the antenna. FIG. 9A is a developed view in which another modified example of the antenna shown in FIG. 7 is developed on a plane. (B) is a plan view of the antenna. (A) is a graph which shows the frequency dependence of VSWR of the antenna device concerning a 5th Example. (B) is a graph showing the frequency dependence of the VSWR of the antenna device according to the eighth embodiment.

  Hereinafter, an embodiment of an antenna device of the present invention will be described with reference to the drawings.

  In the following description, the forward direction (positive y-axis direction in FIG. 1) of the vehicle body 1 is referred to as “forward”, and the backward direction (negative y-axis in FIG. 1) is referred to as “rearward”. The right-hand direction of the vehicle body 1 (positive x-axis direction in FIG. 1) is referred to as “right direction”, and the left-hand direction of the vehicle body 1 (x-axis negative direction in FIG. 1) is referred to as “left direction”. The direction from the chassis of the vehicle body 1 toward the roof (positive z-axis direction in FIG. 1) is referred to as “upward”, and the direction from the roof of the vehicle body 1 toward the chassis (negative z-axis direction in FIG. 1) is “upward”. Downward ". Further, when the left direction and the right direction are referred to without distinguishing the directions, they are referred to as “left and right directions”, and when the upward direction and the down direction are referred to without distinguishing the directions, they are referred to as “vertical directions”.

  Further, in each of the embodiments of the present specification, an in-vehicle antenna device having a spoiler disposed at a rear end of a roof as a housing will be described, but the present invention is not limited thereto. That is, the present invention can also be applied to a vehicle-mounted antenna device arranged at the front end, right end, or left end of the roof.

[First Embodiment]
A vehicle-mounted antenna device 10 according to a first embodiment of the present invention will be described with reference to FIGS.

[Example of mounting the in-vehicle antenna device 10]
First, an example in which a vehicle-mounted antenna device 10 according to a first embodiment of the present invention is mounted on a vehicle body 1 will be described with reference to FIG. FIG. 1A is a perspective view illustrating an external appearance of a vehicle body 1 on which the vehicle-mounted antenna device 10 according to the present embodiment is mounted. FIG. 1B is an enlarged plan view of a part of the vehicle body 1 on which the vehicle-mounted antenna device 10 according to the present embodiment is mounted. Specifically, FIG. 2 is an enlarged plan view of the vehicle-mounted antenna device 10 mounted on the vehicle body 1.

  The vehicle body 1 shown in FIG. 1A is a hatchback type vehicle body. In the vehicle body 1, an outer plate (body panel) including the roof 20 is formed of a metal member such as a steel plate and an aluminum plate, and a surface formed by the roof 20 is substantially horizontal. That is, the roof 20 is formed along a horizontal plane and intersects the up-down direction of the vehicle body 1. In each embodiment of the present specification, the direction along the roof is synonymous with the direction along the horizontal plane, and the direction crossing the roof is synonymous with the direction crossing the horizontal plane. The vehicle-mounted antenna device 10 according to the present embodiment is a vehicle-mounted antenna device having the spoiler 16 as a housing, and is mounted on the rear end of the roof 20.

  As shown in FIG. 1B, the hatch gate 21 of the vehicle body 1 includes a hatch gate panel 21a forming a lower part thereof, a frame 21c forming an upper part thereof, and a rear glass 21b. The frame 21c includes a pair of vertical columns and a pair of horizontal columns, and a rear glass 21b is provided in the frame. The horizontal column on the side (upper side) of the pair of horizontal columns of the frame 21c that is close to the roof 20 is attached to the rear end of the roof 20 by a hinge (not shown). The rear glass 21b secures a rear view from the driver and also functions as a windshield. The hatch gate panel 21a and the frame 21c are made of a metal member.

  A spoiler fixing portion 21d (an antenna device fixing portion described in the claims) is provided on a part of the upper horizontal column of the pair of horizontal columns of the frame 21c. A part of the upper horizontal column of the frame body 21c is protruded rearward, and the protruded part is used as a spoiler fixing part 21d (see FIG. 2A). The spoiler fixing portion 21d is made of a metal member, similarly to the frame 21c. The surface of the spoiler fixing portion 21d to which the spoiler 16 is attached is substantially in the zenith direction, like the surface formed by the roof 20, and is along the horizontal plane. Therefore, the spoiler fixing portion 21d forms the rear end of the roof 20. In the present embodiment, the spoiler fixing portion 21d is a metal member formed integrally with the frame 21c, but is a metal member formed separately from the frame 21c and fixed to the frame 21c with bolts or the like. Is also good.

  The spoiler 16 is attached to the spoiler fixing portion 21d by a fixing means (for example, a bolt or the like) not shown. By being fixed to the spoiler fixing portion 21d, the upper surface of the spoiler 16 and the entire upper surface of the roof 20 are substantially flush with each other. The spoiler 16 has a function of improving the aesthetics of the vehicle body 1 and improving aerodynamic characteristics of the vehicle body 1, and also functions as a housing of the vehicle-mounted antenna device 10 in the present invention. The antenna 11 and the stop lamp 19 are built in the spoiler 16. The spoiler 16 is made of a dielectric (eg, resin) and transmits electromagnetic waves.

  The antenna 11 is arranged at a position that does not interfere with the stop lamp 19 inside the spoiler 16. Specifically, the antenna 11 is arranged to be shifted to the left of the stop lamp 19, avoiding the stop lamp 19 arranged at the center of the spoiler 16 in the left-right direction.

[In-vehicle antenna device 10]
The configuration of the vehicle-mounted antenna device 10 will be specifically described with reference to FIG. FIG. 2 shows a configuration of the vehicle-mounted antenna device 10 according to the present embodiment. FIG. 2A is an enlarged cross-sectional view of a part of the vehicle body 1 on which the vehicle-mounted antenna device 10 is mounted, and is a cross-sectional view taken along the line AA ′ shown in FIG. FIG. FIG. 2B is a developed view in which the antenna 11 included in the vehicle-mounted antenna device 10 is developed on a plane.

  As shown in FIG. 2A, the vehicle-mounted antenna device 10 is configured such that the antenna 11 is placed inside the spoiler 16 in a bent state. Examples of fixing means for fixing the antenna 11 to the spoiler 16 include an adhesive sheet, a double-sided tape, and a resin fastener. The fixing means is not limited, but is preferably made of a non-conductor so as not to hinder transmission and reception of electromagnetic waves. A specific method of bending the antenna 11 will be described later with reference to FIG.

[Antenna 11]
The antenna 11 includes a dielectric substrate, a radiating element formed on the surface of the dielectric substrate, and a connecting portion for connecting a coaxial cable (not shown) and the radiating element. In the present embodiment, a dielectric film 12 is employed as the dielectric substrate. As a material forming the dielectric film 12, for example, a polyimide resin may be mentioned, but it is not limited to this. The antenna 11 configured as described above can be regarded as a film antenna or as an FPC (Flexible printed circuits) substrate.

  In the example of FIG. 2B, a radiating element including a first radiating element 14 and a second radiating element 15 is formed on the surface of the dielectric film 12. The first radiating element 14 and the second radiating element 15 are thin plate-shaped members made of a conductor. For example, a copper foil is used as the first radiating element 14 and the second radiating element 15, but the present invention is not limited to this.

  The connecting portion 13 is a portion where a coaxial line (not shown) is connected to the radiating elements 14 and 15, and includes two feeding points (a pair of feeding points) 13a and 13b. Each of the feeding points 13a and 13b is formed on the surface of each of the radiating elements 14 and 15, respectively. One end of a coaxial line can be connected to the connection portion 13. By connecting the other end of the coaxial cable to a vehicle-mounted device such as a tuner, the vehicle-mounted antenna device 10 can transmit and receive radio waves.

  One conductor (for example, an inner conductor) of the pair of conductors forming the coaxial line is connected to the first radiating element 14 at a first feeding point 13 a which is one feeding point of the connection portion 13. The other conductor (for example, the outer conductor) of the coaxial line is connected to the second radiating element 15 at a second feeding point 13b which is the other feeding point of the connection unit 13. In the present embodiment, a dipole antenna is employed as the antenna 11, but a loop antenna, a monopole antenna, and an inverted-F antenna may be used as the antenna 11. Each radiating element may be a planar radiating element like the radiating elements 14 and 15 of the present embodiment, or may be a linear radiating element.

  The antenna 11 is folded in a valley along the lines B-B 'and C-C' shown in FIG. As a result, the antenna 11 bent in a U-shape (or U-shape) in which the dielectric film 12 is arranged on the outside and the radiation elements 14 and 15 are arranged on the inside is formed. As shown in FIG. 2A, the vehicle-mounted antenna device 10 employs a configuration in which the antenna 11 bent in a U-shape is fixed along the inner wall of the spoiler 16.

  As shown in FIG. 2A, when the vehicle-mounted antenna device 10 is mounted on the rear end of the vehicle body 1, the first radiating element 14 of the antenna 11 is in a direction crossing the feed point 13 a and the roof 20. The second radiating element 15 is drawn out in a downward direction (corresponding to a first direction described in the claims) of the vehicle body 1, and is a direction crossing the roof 20 from the feeding point 13 b, and It is drawn out in an upward direction (corresponding to a second direction described in the claims) which is a direction different from the downward direction. The vehicle-mounted antenna device 10 adopts a configuration in which the first direction and the second direction intersect with the roof 20.

  In the first radiating element 14, a portion that is drawn downward from the feeding point 13a, that is, a line that is valley-folded from the starting end (root) of the first radiating element 14 that is connected to the feeding point 13a. A portion up to a certain CC 'line is defined as a power supply point vicinity portion 14a.

  Since the power supply point vicinity 14a is drawn downward from the power supply point 13a, the direction of the current flowing through the power supply point vicinity 14a is mainly in the vertical direction. Further, the current density of the current flowing through the first radiating element 14 is highest at the beginning of the first radiating element 14 (connection portion with the feed point 13a) and decreases as approaching the end. For this reason, a current having a relatively high current density flows in the vertical direction of the vehicle body 1 in the power supply point vicinity portion 14a. As a result, the first radiating element 14 can increase the ratio of the vertically polarized wave component contained in the radiated electromagnetic wave as compared with the related art (the in-vehicle antenna device described in Patent Document 1).

  Further, the vertically polarized wave has a characteristic that it is less likely to be attenuated by the roof 20 as compared with the horizontally polarized wave. Therefore, even if the roof 20 is made of metal, the on-vehicle antenna device 10 including the first radiating element 14 has a radiation gain of a vertically polarized wave with respect to a direction crossing the roof 20 (here, a forward direction). It can be large enough. As a result, even if the roof is made of metal, the radiation gain of the electromagnetic wave in the direction crossing the roof can be sufficiently increased.

In addition, it is preferable that the width W _14a of the vicinity 14a of the feeding point be equal to or less than の of the shortest wavelength of the electromagnetic wave emitted by the antenna 11. In the present embodiment, since the first radiating element 14 is rectangular, the vicinity _14a of the feeding point is also rectangular, and the width W _14a is constant from the feeding point 13a to the line CC ′. When the power supply point vicinity portion 14a is not rectangular, the maximum value of the width W _14a is preferably equal to or less than の of the shortest wavelength of the electromagnetic wave radiated by the antenna 11.

According to the configuration of the first radiating element 14, the current supplied from the feeding point 13a is prevented from flowing along the left-right direction of the vehicle body 1 in the feeding point vicinity portion 14a, and Facilitates flowing along. Therefore, the radiation gain of the vertically polarized wave can be further increased as compared with the case where the width W _14a is more than の of the shortest wavelength of the electromagnetic wave radiated by the antenna 11. As a result, the radiation gain of the electromagnetic wave in the forward direction of the vehicle body 1 can be further increased.

  In the second radiating element 15, a portion that is drawn upward from the feeding point 13 b, that is, a line that is valley-folded from the starting end (root) of the second radiating element 15 connected to the feeding point 13 b. A portion up to a certain BB ′ line is defined as a power supply point vicinity 15a.

  In the in-vehicle antenna device 10, a portion 15 a near the feeding point of the second radiating element 15 is drawn upward in the vehicle body 1. The feeding point vicinity portion 15a configured as described above can further increase the ratio of the vertically polarized component included in the electromagnetic wave radiated by the vehicle-mounted antenna device 10.

In a configuration in which the feed point vicinity 14a is drawn downward from the feed point 13a and the feed point vicinity 15a is drawn upward from the feed point 13b, the width W is set to increase the radiation gain of vertically polarized waves. It is preferable that each of the width _14a and the width _W15a is equal to or less than 1/2 of the shortest wavelength of the radiated electromagnetic wave from the antenna 11. However, if either of the width _{W 14a} and the width _{W 15a} is 1/2 or less of the shortest wavelength of an electromagnetic wave antenna radiates the shortest of the electromagnetic waves each having a width _{W 14a} and the width _{W 15a} antenna 11 radiates The radiation gain of the vertically polarized wave can be further increased as compared with the case where the wavelength exceeds half of the wavelength.

Further, the antenna 11 of the in-vehicle antenna apparatus 10 arranged at the rear end of the roof 20, along the rear side of the feeding point vicinity 14a, the width _W 14 of the radiating element other than _{15a, W 15} (roof 20 More preferably, the measured width of the radiating element is also not more than の of the shortest wavelength of the electromagnetic wave radiated by the antenna. Here, when the width W ₁₄ of the first radiating element ₁₄ and the width W ₁₅ of the second radiating element 15 are different, both widths W ₁₄ and W ₁₅ are the shortest wavelengths of the electromagnetic waves radiated by the antenna. It is preferably 1/2 or less.

  According to the configuration of the antenna 11, each of the current supplied from the feeding point 13a to the first radiating element 14 and the current supplied from the feeding point 13b to the second radiating element 15 are shifted in the left-right direction of the vehicle body 1. Along the vehicle body 1, and is facilitated to flow along the vertical direction or the vertical direction of the vehicle body 1. That is, the direction of the main current flowing through the first and second radiating elements 14 and 15 can be limited to the vertical direction and the front-back direction of the vehicle body 1. As a result, for example, even when another antenna in which a radiating element extending in the left-right direction of the vehicle body 1 is attached to the rear glass is provided near the vehicle-mounted antenna device 10 having the spoiler 16 as a housing. The radiation elements 14 and 15 of the antenna 11 can be applied to other antennas (radiation elements extending in the left-right direction of the vehicle body 1) or can be suppressed from being affected by the other antennas.

  As described above, in the in-vehicle antenna device 10, the radiating element is pulled out from one feeding point in the first direction, and since the first direction intersects with the roof, the radiating element is vertically polarized as the main polarization component. Can emit waves. The plane of polarization of vertically polarized waves is the direction that intersects the roof that is a metal body. Therefore, when compared with horizontal polarization, vertical polarization is less likely to be affected by the above-described damping effect of the roof in the process of crossing the vehicle body, and can cross the roof without losing the radiation gain. .

  Therefore, even when the roof 20 is a metal body, the vehicle-mounted antenna device 10 disposed at the rear end of the roof 20 has a larger radiation gain in a direction crossing the roof 20 (forward direction) than the conventional antenna. An antenna device can be realized. Therefore, the in-vehicle antenna device 10 can be suitably used as an in-vehicle antenna device using a frequency band having a short wavelength represented by an electromagnetic wave for LTE. In other words, in a conventional in-vehicle antenna device in which the radiating elements inside the spoiler are arranged horizontally, the electromagnetic wave radiated from the antenna has horizontal polarization as the main polarization component. Although it was difficult to apply to an antenna system that requires communication with a base station installed on the ground, such as 3G or LTE, the in-vehicle antenna device of the present invention has a vertical polarization component as a main polarization component. Since it can radiate polarized waves, it can be suitably used as an antenna system that requires communication with a base station installed on the ground, such as 3G or LTE.

  As shown in FIG. 2A, the portion from the B-B ′ line to the end of the second radiating element 15 is arranged in a direction along the roof 20. According to this configuration, the vehicle-mounted antenna device 10 can radiate not only vertically polarized waves but also horizontally polarized waves.

[Second embodiment]
Next, a vehicle-mounted antenna device according to a second embodiment of the present invention will be described with reference to FIG. FIG. 3A is a partially enlarged plan view of the vehicle body 1 on which the vehicle-mounted antenna device 110 according to the present embodiment is mounted. FIG. 3B is an enlarged cross-sectional view of a part of the vehicle body 1 on which the vehicle-mounted antenna device 110 is mounted, and is a cross-sectional view taken along line LL ′ shown in FIG. .

  In the vehicle-mounted antenna device 10A according to the present embodiment, the antenna 11 and the spoiler 16 provided in the vehicle-mounted antenna device 10 according to the first embodiment are changed to spoil antennas 11A and 16A, respectively, which will be described below. Obtained by

  The antenna 11A is obtained by rotating the antenna 11 by 90 degrees counterclockwise when the vehicle-mounted antenna device 10 according to the first embodiment is viewed from above the vehicle body 1 (see FIG. 1B). Is obtained by reversing the direction in which the end of the first radiating element 14 extends from left to right of the vehicle body 1. In other words, the power supply point vicinity 14Aa including one power supply point is pulled out in the lower direction of the vehicle body 1 which is the first direction, and the power supply point proximity part 14Ab including the other power supply point is the vehicle body having the second direction. 1 is pulled upward. Further, the end of the first radiating element 14A extends to the right of the vehicle body 1, and the end of the second radiating element 15A extends to the left of the vehicle body 1 ((b) of FIG. 3). reference). Focusing on the radiating element bending method, the radiating elements 14 and 15 are bent in a U-shape (or a U-shape), whereas the radiating elements 14A and 15A are formed in a step shape (or a Z-shape). It is bent.

  As shown in FIG. 3B, the spoiler 116 is provided with an antenna mounting base 116a on which the antenna 111 is mounted. The antenna mounting table 116a includes a plane intersecting with the roof 20 and a plane along the roof 20 and located inside the spoiler 116. More specifically, the plane that intersects with the roof 20 is the yz plane on the seating axis shown in FIG. 3B, and the plane along the roof 20 is the xy plane on the coordinate axes shown in FIG. As shown in FIG. 3B, the antenna mounting base 116a forms a step for mounting the antenna 111, which protrudes inside the spoiler 116.

  The antenna 11A can be fixed in the spoiler 16A by using fixing means similar to the fixing means for fixing the antenna 11 in the spoiler 16. As shown in FIG. 3A, the shape of the spoiler 16A when viewed in plan is shorter in the front-rear direction of the vehicle body 1 and longer in the left-right direction of the vehicle body 1. Further, when comparing the internal space between the front region and the rear region of the spoiler 16A, the space in the rear region greatly exceeds the space in the front region. This is because the spoiler fixing portion 21d is provided in the front region of the spoiler 16A, and the upper surface of the spoiler and the upper surface of the entire roof 20 are made substantially flush.

  Since the radiating elements 114 and 115 of the antenna 111 extend in the longitudinal direction of the spoiler 116, the length from the start to the end of the radiating element is designed to be longer than that of the radiating elements 14 and 15 of the antenna 11. can do. As a result, the antenna 111 can improve the radiation gain as compared with the antenna 11. In addition, the antenna 111 can be easily mounted on the spoiler 116 as compared with the antenna 11 because it may be mounted on the rear region of the spoiler 116 having a large space.

  In the in-vehicle antenna device 110 configured as described above, the feeding point vicinity portion 114a is drawn out in the lower direction of the vehicle body 1, and the feeding point vicinity portion 115a is drawn out in the vehicle body 1 in the upper direction. Therefore, the vehicle-mounted antenna device 110 can radiate a vertically polarized wave as a main polarized wave component. Therefore, even when the roof 20 is a metal body, the vehicle-mounted antenna device 110 can realize a vehicle-mounted antenna device that has a larger radiation gain in a direction crossing the roof 20 (forward direction) than in the related art.

[Third embodiment]
Next, a vehicle-mounted antenna device 30 according to a third embodiment of the present invention will be described with reference to FIG. The in-vehicle antenna device 30 is obtained by changing the antenna 11 included in the in-vehicle antenna device 10 according to the first embodiment to an antenna 31 described below.

  FIG. 4A is a cross-sectional view of the vehicle body 1 on which the vehicle-mounted antenna device 30 according to the present embodiment is mounted. FIG. 4B is a development view of the antenna 31 provided in the vehicle-mounted antenna device 30.

  The antenna 31 is different from the antenna 11 in the U-shaped bending position. In other words, except for the bending position, the antenna 31 has the same configuration as the antenna 11. Specifically, in the antenna 31, a straight line including the feeding point 33b and an edge serving as a start end of the second radiating element 35 is adopted as a D-D 'line corresponding to one bending position. Further, a straight line closer to the end of the first radiating element 34 as compared with the line C-C 'shown in FIG.

  The antenna 31 bent in a U-shape along the lines D-D 'and E-E' is placed inside the spoiler 16, as shown in FIG. Specifically, when the in-vehicle antenna device 30 is mounted on the rear end of the vehicle body 1, the power supply point 33 a of the first radiating element 34 extends downward from the power supply point 33 a in the first direction. (Direction intersecting the roof 20), and the second radiating element 35 is pulled out from the feeding point 33b in the second direction, that is, in the front direction of the vehicle body (the direction along the roof 20).

  In addition, the antenna 31 further includes an overlapping portion 35b that overlaps with a metal member (spoiler fixing portion 21d) that forms the rear end of the roof 20 and that is separated from the metal member. In the present embodiment, the overlapping portion 35b is provided in a portion including the end of the second radiating element 35. However, the position at which the overlapping portion 35b is provided is not limited to the portion including the terminal end, and may be provided at least at a part of the portion of the second radiating element 35 extending in the direction along the roof 20. Since the overlapping portion 35b overlaps the spoiler fixing portion 21d made of a conductor, the spoiler fixing portion 21d is used as the ground of the antenna 31, and the radiation gain toward the front of the vehicle body can be further increased.

  Note that, in the present embodiment, a configuration is adopted in which the overlapping portion 35b is provided in a part of the second radiating element 35. However, it is also possible to adopt a configuration in which an overlapping portion provided on a part of the first radiating element 34 overlaps the spoiler fixing portion 21d. Which of the radiating elements 34 and 35 is provided with the overlapping portion depends on the position of the connection part 33, the shape of each of the radiating elements 34 and 35, the shape of the spoiler 16, and the relative position between the antenna 31 and the spoiler fixing part 21d. What is necessary is just to determine suitably according to a positional relationship.

[Fourth embodiment]
Next, a vehicle-mounted antenna device 60 according to a fourth embodiment of the present invention will be described with reference to FIG. The in-vehicle antenna device 60 is configured such that the spoiler 16 that functions as a housing of the in-vehicle antenna device 30 (see FIG. 4) according to the third embodiment is changed to a spoiler 66, and then the in-vehicle antenna device 30 is provided. The antenna 31 is obtained by changing the present antenna 31 to the antenna 61.

  FIG. 5A is an enlarged cross-sectional view of a part of the vehicle body 1 on which the vehicle-mounted antenna device 60 is mounted. FIG. 5B is a developed view of the antenna 61 provided in the vehicle-mounted antenna device 60.

  Compared to the spoiler 16, the spoiler 66 is provided with an antenna mounting base 66a for mounting the antenna 61 at the rear end of the inner wall. As shown in FIG. 5A, the antenna mounting table 66a includes a plane intersecting with the roof 20 and a plane along the roof 20. More specifically, the antenna mounting table 66a includes a plane extending in the up-down direction of the vehicle body 1 (a zx plane on the seat axis shown in FIG. 5A) and a plane extending in the front-rear direction of the vehicle body 1 (FIG. Xy plane on the coordinate axes shown in FIG. The antenna mounting base 66a forms a step that protrudes inside the spoiler 66.

  The in-vehicle antenna device 60 is configured to mount the antenna 61 in a state of being bent along the internal shape of the spoiler 66. As the fixing means for fixing the antenna 61 to the spoiler 66, the same fixing means as the fixing means for fixing the antennas 11, 31 to the spoiler 16 can be used.

  In order to be mounted on the spoiler 66, the antenna 61 is folded in a valley along a line FF 'shown in FIG. 5B, and is cut along a line GG' shown in FIG. 5B. And folded in the mountains. As a result, an antenna 61 bent in a Z shape is formed. As shown in FIG. 5A, the vehicle-mounted antenna device 60 employs a configuration in which the antenna 61 bent in a Z-shape is fixed along the inner wall of the spoiler 66 and the antenna mounting table 66a.

  As shown in FIG. 5A, when the vehicle-mounted antenna device 60 is mounted on the rear end of the vehicle body 1, the first radiating element 64 of the antenna 61 is in a direction crossing the feed point 63 a and the roof 20. The second radiating element 65 is pulled out in a downward direction (corresponding to a first direction described in the claims) of the vehicle body 1, and is a direction crossing the power supply point 63 b to the roof 20. It is drawn out in an upward direction (corresponding to a second direction described in the claims) which is a direction different from the downward direction. The vehicle-mounted antenna device 60 employs a configuration in which the first direction and the second direction intersect the roof 20.

  In the first radiating element 64, a portion that is drawn downward from the feeding point 63a, that is, a line that is mountain-folded from the starting end (root) of the first radiating element 64 that is connected to the feeding point 63a. A portion up to a certain GG ′ line is defined as a power supply point vicinity 64a.

  Since the power supply point vicinity 64a is drawn downward from the power supply point 63a, the direction of the current flowing through the power supply point vicinity 64a is mainly the vertical direction. Further, the current density of the current flowing through the first radiating element 64 is highest at the beginning of the first radiating element 64 (connection portion with the feeding point 63a) and decreases as approaching the end. For this reason, a current having a relatively high current density flows in the vertical direction of the vehicle body 1 in the power supply point vicinity portion 64a. As a result, the first radiating element 64 can make the ratio of the vertically polarized wave component contained in the radiated electromagnetic wave larger than that of the related art (the in-vehicle antenna device described in Patent Document 1).

  Further, the vertically polarized wave has a characteristic that it is less likely to be attenuated by the roof 20 as compared with the horizontally polarized wave. Therefore, even if the roof 20 is made of metal, the on-vehicle antenna device 10 including the first radiating element 14 has a radiation gain of a vertically polarized wave with respect to a direction crossing the roof 20 (here, a forward direction). It can be large enough. As a result, even if the roof is made of metal, the radiation gain of the electromagnetic wave in the direction crossing the roof can be sufficiently increased.

  In the second radiating element 65, a portion that is drawn upward from the feeding point 63b, that is, a line that is valley-folded from the starting end (root) of the second radiating element 65 connected to the feeding point 63b. A portion up to a certain FF ′ line is defined as a power supply point vicinity 65a. According to this configuration, the second radiating element 65 sets the ratio of the vertically polarized component included in the electromagnetic wave radiated similarly to the first radiating element 64 to be higher than that of the conventional (vehicle-mounted antenna device described in Patent Document 1). Can also be many. Therefore, the antenna 61 can further increase the ratio of the vertically polarized wave component contained in the radiated electromagnetic wave as compared with the related art (the on-vehicle antenna device described in Patent Document 1).

  In addition, the antenna 61 further includes an overlapping portion 65b that extends along the roof 20 and overlaps the spoiler fixing portion 21d. In the present embodiment, the overlapping portion 65b is provided at a portion including the end of the second radiating element 35, similarly to the overlapping portion 35b included in the antenna 31. Since the overlapping portion 65b overlaps the spoiler fixing portion 21d made of a conductor, the spoiler fixing portion 21d is used as the ground of the antenna 61, and the radiation gain with respect to the front of the vehicle body can be further increased.

  Note that, in the present embodiment, a configuration is employed in which the overlapping portion 65b is provided in a part of the second radiating element 65. However, as described in the third embodiment, a configuration in which an overlapping portion provided in a part of the first radiating element 64 overlaps with the spoiler fixing portion 21d can be adopted.

[Modification of antenna]
Hereinafter, modified examples of the antennas 11, 111, 31, and 61 included in the vehicle-mounted antenna devices 10, 110, 30, and 60 according to the first to fourth embodiments will be described with reference to FIGS. I do.

  FIG. 6A is a developed view of an antenna 41 according to a first modification, and FIG. 6B is a side view of the antenna 41 as viewed from an arrow. FIG. 6C is a developed view of an antenna 51 according to a second modification, and FIG. 6D is a side view of the antenna 51 as viewed from an arrow. In FIG. 6B, the spoiler 16 as a housing is omitted to make the configuration of the antenna 41 easy to understand. Similarly, the spoiler 16 is omitted in FIG. FIG. 7 is an expanded view of an antenna 71 according to a third modification. FIG. 8 is a developed view showing another example of the antenna 71 which is the third modified example shown in FIG. FIG. 9 is an expanded view of an antenna 81 according to a fourth modification.

(First Modification and Second Modification)
As shown in FIG. 6A, the antenna 41 is pulled out from the feeding point 43a in the downward direction of the vehicle body 1 (direction intersecting with the roof 20), and from the feeding point 43b in the forward direction of the vehicle body 1 (the direction along the roof 20). ) Is provided with a single and annular radiating element 44 drawn out. That is, in the first modification, the antenna 41 which is a loop antenna is employed instead of the antenna 11 which is a dipole antenna.

  As shown in FIG. 6C, the antenna 51 includes a first conductor 55 pulled out from the power supply point 53a in a downward direction (a direction intersecting the roof 20) and a forward direction from the power supply point 53b toward the vehicle body. A single conductor composed of the second conductor 56 drawn out (in the direction along the roof 20) and the third conductor 57 connecting the middle part of the first conductor 55 and the middle part of the second conductor 56, respectively. A radiating element 54 is provided.

  In the radiating element 54, when the first conductor 55 functions as a ground plane, the third conductor 57 grounds an intermediate portion of the second conductor 56. According to this configuration, the antenna 51 functions as an inverted-F antenna.

  When the radiating element 54 employs a configuration in which power is supplied to each of the first conductor 55 and the second conductor 56, the radiating element 54 is a radiating element obtained by adding a branch to the annular radiating element. Function. In this case, the ring-shaped radiating element includes the first conductor 55 from the beginning to the middle, the second conductor 56 from the beginning to the middle, and the third conductor 57. The branch from the middle to the end of the first conductor 55, and the other branch from the middle to the end of the second conductor 56. According to this configuration, the antenna 51 functions as an antenna obtained by adding a branch to the loop antenna.

  As described above, in the second modification, instead of the antenna 11 which is a dipole antenna, the antenna 51 which functions as an inverted F-type antenna or an antenna obtained by adding a branch to a loop antenna is employed.

  The antennas 41 and 51 provided in the vehicle-mounted antenna devices according to these modified examples are pulled out from the power supply points 43a and 53a, which are one of the power supply points, in the downward direction of the vehicle body (negative z-axis direction in the figure). Radiating elements 44 and 54 are drawn out from the feeding points 43b and 53b, which are feeding points of the vehicle, in the forward direction of the vehicle body (positive y-axis direction in the figure). Therefore, the in-vehicle antenna devices according to these modified examples can sufficiently increase the radiation intensity of the electromagnetic wave toward the front of the vehicle body.

(Third Modification)
As shown in FIG. 7, an antenna 71 according to a third modification changes the shape of the first radiating element 74 to a bell-shaped (or cup-shaped) as compared with the antennas 11, 111, 31, and 61. Obtained by: Specifically, by replacing each of two corners of the first radiating element 74 that are close to the second radiating element 75 with a quadrant ellipse 74b and a quadrant ellipse 74c, a bell-shaped A first radiating element 74 is obtained. By changing the shape of the first radiating element 74 from a rectangle to a bell shape, the distance between the feeding point vicinity 74a of the first radiating element 74 and the feeding point vicinity 75a of the second radiating element 75 is continuously changed. Can be changed to As a result, the resonance frequency of the antenna 71 can be adjusted, and the operating band can be adjusted.

  In addition, the first radiating element 74 has a feeding point 73a provided at a protruding portion protruding from a side sandwiched between two rounded corners. The first radiating element 74 configured as described above is drawn out from the feed point 73a in a direction crossing the roof 20 in a downward direction (corresponding to a first direction described in claims). .

  On the other hand, the second radiating element 75 has a feed point 73b provided in the vicinity of a notch cut out according to the shape of the projection of the first radiating element 74. The second radiating element 75 configured as described above is an upward direction that is a direction intersecting the roof 20 from the feeding point 73b and that is different from the downward direction of the vehicle body 1 (the second direction described in the claims). (Corresponding to the direction).

  The antenna 71 shown in FIG. 7 has the first direction and the first direction similar to the antennas 11, 11A, and 61 included in the vehicle-mounted antenna devices 10, 10A, and 60 according to the first, second, and fourth embodiments. A configuration in which the two directions cross the roof 20 is adopted.

  Further, each of the width of the first radiating element 74 and the width of the second radiating element 75 is configured to be 以下 or less of the shortest wavelength of the electromagnetic wave transmitted by the antenna 71.

  Specifically, for example, similarly to the antenna 11 included in the in-vehicle antenna device 10 according to the first embodiment, a portion of the first radiating element 74 that is drawn downward from the feeding point 73a, that is, A portion from the starting end (root) of the first radiating element 74 connected to the feeding point 73a to the line II ′, which is a line that is folded in a valley, is defined as a feeding point neighborhood 74a. Further, in the second radiating element 75, a line that is drawn upward from the feeding point 73b, that is, an HH ′ line that is a valley-folded line from the starting end (root) of the second radiating element 75 The portion up to this point is referred to as a feeding point vicinity 75a. Then, like the antenna 61 included in the vehicle-mounted antenna device 60 according to the fourth embodiment, a portion including the end of the second radiating element 75 configured to overlap the spoiler fixing portion 21d is overlapped with the overlapping portion 75b. And

  Further, for example, similarly to the antenna 31 included in the vehicle-mounted antenna device 30 according to the second embodiment, the first radiating element 74 is connected to a portion of the first radiating element 74 that is drawn downward from the feeding point 73a, that is, connected to the feeding point 73a. The portion from the starting end (root) of the first radiating element 74 to the line II ′ which is a mountain-folded line is referred to as a feeding point vicinity 74a. Further, in the second radiating element 75, a line that is drawn upward from the feeding point 73b, that is, an HH ′ line that is a valley-folded line from the starting end (root) of the second radiating element 75 The portion up to this point is referred to as a feeding point vicinity 75a.

  Further, for example, similarly to the antenna 61 included in the vehicle-mounted antenna device 60 according to the fourth embodiment, in the first radiating element 74, a portion of the first radiating element 74 that is drawn downward from the feeding point 73 a, that is, to the feeding point 73 a. The portion from the starting end (root) of the connected first radiating element 74 to the line II ′, which is a mountain-folded line, is defined as a feeding point vicinity 74a. Further, in the second radiating element 75, a line that is drawn upward from the feeding point 73b, that is, an HH ′ line that is a valley-folded line from the starting end (root) of the second radiating element 75 The portion up to this point is referred to as a feeding point vicinity 75a. Further, the overlapping portion 75b is provided at a portion including the end of the second radiating element 75, and is located along the spoiler fixing portion 21d constituting the rear end of the roof 20, and is separated from the spoiler fixing portion 21d. It is configured to overlap in a state.

  Further, the bell-shaped antenna 71 may be configured as shown in FIG. That is, in the first radiating element 74, a portion that is drawn upward from the feeding point 73a, that is, from the starting end (root) of the first radiating element 74 connected to the feeding point 73a, valley folds (or peaks). The portion up to the line II ′, which is the line to be folded, is defined as the vicinity of the feeding point. The width of the vicinity of the feeding point is configured to be equal to or less than の of the shortest wavelength of the electromagnetic wave radiated by the antenna, and the width of the region from the line II ′ to the end is the width of the vicinity of the feeding point. It is configured to be wider.

  Similarly, the second radiating element 75 is a line that is valley-folded from a portion that is drawn downward from the feeding point 73b, that is, a line that is valley-folded from the starting end (root) of the second radiating element 75. The portion up to the 'line is the vicinity of the feeding point. The width of the vicinity of the feeding point is configured to be equal to or less than の of the shortest wavelength of the electromagnetic wave radiated by the antenna, and the width of the region from the line HH ′ to the end is the width of the vicinity of the feeding point. It is configured to be wider.

(Fourth modification)
As shown in FIG. 9, an antenna 81 which is a fourth modification of the antenna 11 includes a first conductor 85 pulled out from a feed point 83 a in a downward direction (a direction intersecting with the roof 20) of the vehicle body 1, and a feed point The second conductor 86 extends upward from the vehicle body 83 (in a direction intersecting the roof 20) and includes a third conductor 87 that connects the first conductor 85 and the second conductor 86. One radiating element 84 is provided.

  The first conductor 85 includes a feed point neighborhood 85a drawn from the feed point 83a, and a conductor 85b extending along the left-right direction of the vehicle body 1 when the vehicle-mounted antenna device 60 is disposed at the rear end of the roof 20. And a conductor 85c extending in a direction intersecting with the conductor 85b, that is, along the front-back direction of the vehicle body 1.

  The second conductor 86 has a power supply point vicinity portion 86a drawn from the power supply point 83b. In addition, the overlapping portion 84b, which is a region from the middle to the end of the second conductor 86, overlaps with the spoiler fixing portion 21d while being separated from the spoiler fixing portion 21d.

  The antenna 81 including the radiating element 84 thus configured functions as an inverted-F antenna by grounding the feeding point 83a, that is, by causing the first conductor 85 to function as a ground plane.

  In the in-vehicle antenna device 60 according to the present modification, the resonance frequency of the antenna 81 is changed by adjusting the distance between each of the feeding point vicinity 85a and the conductor 85b and the feeding point vicinity 86a in the area A1. Can be. As a result, the operating band of the vehicle-mounted antenna device 60 can be adjusted. Similarly, by adjusting the shape of the conductor 85c, the distance between the conductor 85c and the second conductor 86 in the region A2 can be adjusted, and as a result, the operating band of the vehicle-mounted antenna device 60 can be adjusted. .

[First Embodiment]
Hereinafter, an example of the vehicle-mounted antenna device 10 according to the first embodiment will be described. The in-vehicle antenna device 10 according to the present embodiment employs the antenna 71 shown in FIG.

  The on-vehicle antenna device 10 of the present embodiment is mounted on the rear end of the roof 20 of the hatchback type vehicle body 1, more specifically, on the top of a hatch gate. As an electromagnetic wave radiated from the antenna 11, an electromagnetic wave of a frequency called 800 MHz band for LTE (specifically, 830 MHz) was used.

  FIG. 10 is a graph showing the direction dependence of the radiation gain in the xy plane obtained by the vehicle-mounted antenna device 10 according to the present embodiment. In FIG. 10, a broken line indicates the radiation gain of horizontal polarization, a dotted line indicates the radiation gain of vertical polarization, and a solid line indicates the radiation gain of horizontal polarization and vertical polarization, that is, the radiation gain of all polarizations. The unit is [dBi].

  Referring to FIG. 10, it can be seen that the radiation gain of the vehicle body 1 in the forward direction is weaker than the radiation gain of the vehicle body 1 in the rear direction, but exceeds the radiation gain sufficient for use as the vehicle-mounted antenna device. .

[Second embodiment]
Hereinafter, an example of the vehicle-mounted antenna device 110 according to the second embodiment will be described. The execution conditions are the same as in the first embodiment. The in-vehicle antenna device 110 according to the present embodiment employs the bell-shaped antenna 71 shown in FIG. The total length (the sum of the length of the first radiating element 74 and the length of the second radiating element 75) of the antenna 71 employed here is the same as the total length of the antenna 11 (the first radiating element 14) according to the first embodiment. (Sum of the length of the second radiating element 15 and the length of the second radiating element 15).

  The on-vehicle antenna device 110 of this embodiment is mounted on the rear end of the roof 20 of the hatchback-type vehicle body 1, more specifically, on the top of a hatch gate. As an electromagnetic wave radiated from the antenna 111, an electromagnetic wave of a frequency called 800 MHz band for LTE (specifically, 830 MHz) was used.

  FIG. 11 is a graph showing the direction dependency of the radiation gain in the xy plane obtained by the vehicle-mounted antenna device 110 according to the present embodiment. In FIG. 11, a broken line indicates the radiation gain of horizontal polarization, a dotted line indicates the radiation gain of vertical polarization, and a solid line indicates the radiation gain of horizontal polarization and vertical polarization, that is, the radiation gain of all polarizations. The unit is [dBi].

  Referring to FIG. 11, it can be seen that the radiation gain of the vehicle body 1 in the forward direction is weaker than the radiation gain of the vehicle body 1 in the rear direction, but exceeds the radiation gain sufficient for use as the vehicle-mounted antenna device. .

  The direction dependency of the radiation gain in the xy plane obtained by the vehicle-mounted antenna device 110 and the direction dependency of the radiation gain in the xy plane obtained by the vehicle-mounted antenna device 10 of the first embodiment (see FIG. 10). ), It can be seen that the in-vehicle antenna device 110 exceeds the in-vehicle antenna device 10 in each of the radiation gain in the forward direction and the radiation gain in the rear direction of the vehicle body 1. This is because the radiating elements 114, 115 (74, 75) of the on-vehicle antenna device 110 extend along the longitudinal axis of the spoiler 116, and the length of the radiating elements 114, 115 (74, 75) is It is thought to be due to being longer than the length of the radiating elements 14, 15 of the device 10.

[Third embodiment]
Hereinafter, an example of the vehicle-mounted antenna device 30 according to the third embodiment will be described. The execution conditions are the same as in the first embodiment. The on-vehicle antenna device 30 according to the present embodiment employs the same radiating element shape as the bell-shaped antenna 71 shown in FIG.

  FIG. 12 is a graph showing the direction dependence of the radiation gain in the xy plane obtained by the vehicle-mounted antenna device 30 according to the present embodiment. In FIG. 12, the broken line indicates the radiation gain of horizontal polarization, the dotted line indicates the radiation gain of vertical polarization, and the solid line indicates the sum of horizontal polarization and vertical polarization, that is, the radiation gain of all polarizations. The unit is [dBi].

  It can be seen that the radiation gain of the vehicle-mounted antenna device 30 according to the third embodiment is improved in all directions of the vehicle body 1 as compared with the first embodiment shown in FIG. In particular, it can be seen that it is significantly improved in the forward direction of the vehicle body 1. This improvement is considered to be due to the overlapping portion 35b including the end of the second radiating element 35 overlapping the roof 20.

[Fourth embodiment]
The first to fourth embodiments have been described above assuming that the vehicle-mounted antenna device according to the embodiment of the present invention is disposed at the rear end of the roof 20. As shown in FIG. 1, a hatch gate 21 is provided at a rear end of a roof 20 in the vehicle body 1. The rear glass 21b included in the hatch gate 21 has a flat surface made of an insulator. Therefore, a film antenna for receiving a broadcast signal for DTV or a broadcast signal for FM may be attached to the upper end side of the rear glass 21b.

  In this case, since the in-vehicle antenna device according to one embodiment of the present invention and the film antenna attached to the rear glass 21b are close to each other, electromagnetic coupling may occur between the two antennas and influence may occur. .

  In this example, in order to investigate the influence of the coupling between the antennas, a vehicle antenna device 10 according to the first embodiment and a TDV film antenna (hereinafter, referred to as a TDV) attached to the upper end of the rear glass 21b. (DTV antenna), the coupling generated between the vehicle-mounted antenna device 10 and the DTV antenna was measured.

(Measurement system)
The configuration of the measurement system for measuring the above binding is as follows. The in-vehicle antenna device 10 according to the first embodiment was connected to the first port of the network analyzer, and the DTV antenna was connected to the second port of the same network analyzer. The first port is an output port for outputting a high-frequency signal from the network analyzer. The second port is an input port for inputting a high-frequency signal to the network analyzer.

  The in-vehicle antenna device 10 transmits the high-frequency signal supplied from the first port. The DTV antenna receives the high-frequency signal emitted by the vehicle-mounted antenna device 10 and supplies the signal to the second port. The network analyzer determines, based on the high-frequency signal output from the first port and the high-frequency signal input from the second port, the coupling strength generated between the vehicle-mounted antenna device 10 and the DTV antenna as a transmission characteristic S21. calculate.

  The stronger the coupling between the vehicle-mounted antenna device 10 and the DTV antenna, the more efficiently the DTV antenna receives the high-frequency signal transmitted from the vehicle-mounted antenna device 10. As a result, the stronger the bond, the higher S21 will be. That is, in order to suppress the influence of the in-vehicle antenna device 10 and the DTV antenna, it is preferable to suppress S21.

(Configuration of on-vehicle antenna device 10)
In this embodiment, two types of in-vehicle antenna devices 10 obtained by modifying the antenna 11 of the in-vehicle antenna device 10 are employed. Specifically, the antenna 71 (see FIG. 7) is used as the antenna of the first vehicle-mounted antenna device 10, and the antenna 81 (see FIG. 9) is used as the antenna of the second vehicle-mounted antenna device 10. did. Here, in the two types of in-vehicle antenna devices 10, the overlapping portions 74b and 84b of the radiating elements of the antennas 71 and 81 are along the spoiler fixing portion 21d which is a metal member and are separated from the spoiler fixing portion 21d. Superimposed in the state. In addition, the width of the radiating elements 74 and 75 measured along the rear end side of the roof 20 is set to １ ／ or less of the shortest wavelength of the electromagnetic wave transmitted by the antenna 71, specifically, about 1 / 2.8. The antenna 71 is a dipole antenna provided with radiating elements 74 and 75. The antenna 81 is an inverted-F antenna including a first conductor 85, a second conductor 86, and a third conductor 87. The first conductor 85 includes a portion 85a near the feeding point, a conductor 85b, and a conductor 85c. The feeding point vicinity 85a is drawn downward from the feeding point 83a. The conductor 85b extends along the left-right direction of the vehicle body 1. The conductor 85c extends along the front-back direction of the vehicle body 1.

(Configuration of DTV antenna)
In this embodiment, a film antenna in which a rectangular loop antenna is formed on a dielectric film is used as the DTV antenna. The DTV antenna was attached to the upper end side of the rear glass 21b in a direction in which the long side direction of the loop antenna coincided with the left-right direction of the vehicle body 1. This is to prevent the DTV antenna from obstructing the rear view of the driver of the vehicle body 1.

(S21)
FIG. 13 shows transmission characteristics S21 measured using each of the vehicle-mounted antenna device 10 including the antenna 71 and the vehicle-mounted antenna device 10 including the antenna 81. As shown in FIG. 13, S21 of the vehicle-mounted antenna device 10 including the antenna 71 was lower than S21 of the vehicle-mounted antenna device 10 including the antenna 81. That is, it has been found that the vehicle-mounted antenna device 10 including the antenna 71 can suppress the coupling between the DTV antenna and the vehicle-mounted antenna device 10 including the antenna 81.

  This result can be interpreted as follows. In the present embodiment, the width of the radiating elements 74 and 75 provided in the antenna 71 is set to 以下 or less of the shortest wavelength of the electromagnetic wave transmitted by the antenna 71, specifically, about 1 / 2.8. Therefore, most of the current supplied from the feeding point 73a and flowing through the first radiating element 74 and the current supplied from the feeding point 73b and flowing through the second radiating element 75 change their flowing directions to the radiating elements 74 and 75. , That is, the longitudinal direction of the vehicle body 1.

  On the other hand, since the first conductor 85 provided in the antenna 81 is provided with the conductor 85b extending in the left-right direction of the vehicle body 1, the first conductor 85 is fed from the feed point 83a and is fed through the feed point vicinity 85a to the conductor 85b. , The flowing direction of the current is limited to the left and right directions of the vehicle body 1.

  The DTV antenna is attached to the antenna 71 and the antenna 81 configured as described above so that the long side direction of the loop antenna coincides with the left-right direction of the vehicle body 1. Therefore, when the high-frequency signal vibrating along the front-back direction of the vehicle body 1 and the high-frequency signal vibrating along the left-right direction of the vehicle body 1 are compared, the latter is more efficiently received. The antenna 71 can limit the direction of the main current flowing through the radiating elements 74 and 75 to the front-back direction of the vehicle body 1. As a result, the in-vehicle antenna device 10 including the antenna 71 can suppress the influence on the DTV antenna or the influence from the DTV antenna as compared with the in-vehicle antenna device 10 including the antenna 81. .

[Fifth Embodiment]
Next, an in-vehicle antenna device 90 according to a fifth embodiment of the present invention will be described with reference to FIGS. For convenience of description, members having the same functions as those described in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted.

  FIG. 14 is an enlarged cross-sectional view of a part of the vehicle body 1 on which the vehicle-mounted antenna device 90 is mounted, taken along the line A-A ′ in FIG. The antenna is a developed view in which the antenna 91A or 91B provided in the vehicle-mounted antenna device 90 is developed on a plane. In FIG. 15, illustration of the dielectric film 12 is omitted. FIG. 16 shows the shape of two edges connecting the feeding point and the corner of the second radiating element 95A or 95B constituting the antenna 91A or 91B, which is separated from the feeding point in the longitudinal direction of the radiating element 95A or 95B. FIG. 3 is an explanatory diagram showing a broken line and a one-dot chain line.

  The spoiler 16 'as a casing of the vehicle-mounted antenna device 90 has a difference in shape and size from the spoiler 16 shown in FIG. 2 or FIG. 4, but since this difference is not essential, the difference is described in detail. Description is omitted. Therefore, the antenna 91A or 91B may be attached to the spoiler 16 shown in FIG. 2 or FIG.

[In-vehicle antenna device 90]
The configuration of the vehicle-mounted antenna device 90 will be specifically described with reference to FIG. As shown in FIG. 14, the in-vehicle antenna device 90 is configured to mount the antenna 91A or 91B in a state of being bent inside the spoiler 16 '. However, the in-vehicle antenna device 90 is shown in FIG. 2 and the in-vehicle antenna device 90 shown in FIG. 4 in that the dielectric film 12 which is a component of the antenna 91A or 91B is not brought into close contact with the inner wall of the spoiler 16 ′. This is different from the vehicle-mounted antenna device 30. In other words, in the case of the vehicle-mounted antenna device 90, a space is provided between the dielectric film 12 and the inner wall of the spoiler 16 '. By providing this space, it becomes easy to mount the antenna 91A or 91B on the spoiler 16 '.

  The bent state of the antenna 91A or 91B will be described in more detail. As a result of being bent in a U-shape, the antenna 91A or 91B includes an upper wall portion and a lower wall portion facing in the vertical direction (z-axis direction) of the vehicle body 1, and a standing wall portion connecting the upper wall portion and the lower wall portion. Have. The upper wall portion and the lower wall portion are parallel to the front-rear direction (y-axis direction) of the vehicle body 1 as shown in FIG. Further, since the upright wall portion is parallel to the vertical direction (z-axis direction) of the vehicle body 1, each of the upper wall portion and the lower wall portion forms 90 degrees with the upright wall portion.

  More specifically, the space is provided between the rear wall and the rear wall of the spoiler 16 'which is parallel to the vertical wall. Further, a space is provided between the bottom wall of the spoiler 16 'facing the lower wall and the lower wall.

  An example of the fixing means for fixing the antenna 91A or 91B to the spoiler 16 'may be the same as that of the above-described embodiment, but includes a support member located inside the U-shape of the antenna 91A or 91B bent in a U-shape. The antenna 91A or 91B may be fixed around the support. The support is fixed to the spoiler 16 '.

  Alternatively, as shown in FIG. 15, a plurality of holes are formed in the first radiating element 94A or 94B and the second radiating element 95A or 95B constituting the antenna 91A or 91B, and the dielectric film 12 not shown in FIG. 96 and 97 may be provided as appropriate, and a plurality of protrusions (hooks) may be provided on the spoiler 16 ′ and the support in accordance with the positions of the holes 96 and 97. In this embodiment, the antenna 91A or 91B can be fixed by fitting or engaging the plurality of protrusions into the plurality of holes 96 and 97.

[Antenna 91A / 91B]
The most important difference between the antenna 91A or 91B and the antenna 11 (FIG. 2), the antenna 31 (FIG. 4), the antenna 71 (FIG. 7), and the like is the shape of the second radiating element. The first radiating elements 94A and 94B have a bell-shaped shape like the first radiating element 74 (FIG. 7) so as to obtain the above-described effect that the operation band can be adjusted. It is not limited to a bell type.

  The features common to the second radiating elements 95A and 95B are as follows. That is, when a rectangle having the same width as the maximum width of the second radiating elements 95A and 95B parallel to the left-right direction (x-axis direction) of the vehicle body 1 and long in the front-rear direction (y-axis direction) of the vehicle body 1 is considered. In addition, two long sides extending in the front-rear direction of the vehicle body 1 are depressed toward the center of the rectangle. In other words, a notch or a concave shape is formed on the long side of, for example, the copper foil having the rectangular shape. Hereinafter, a contour corresponding to the long side of the second radiating elements 95A and 95B having the cutout or concave shape formed on the long side is referred to as a long edge.

  By setting the shapes of the second radiating elements 95A and 95B in this manner, the distance when the current flows along the long edge is set to a band targeted by the present invention (an example of a telephone band). (698 to 960 MHz), it can be ensured to be long according to the low frequency band (698 to 854 MHz).

  In response to the electromagnetic wave radiated by the antenna 91A, the current flowing through the second radiating elements 95A and 95B flows through the upper surface, the lower surface, and the peripheral edge. Greater than density. Therefore, by extending the distance when the current flows along the long edge, the band of the antenna can be effectively expanded particularly to the low frequency side. Hereinafter, the configurations of the antennas 91A and 91B and the distance will be described in more detail.

(Antenna 91A)
As shown in FIG. 15, the antenna 91A includes a first bell-shaped radiating element 94A and a second radiating element 95A having two long edges formed with the concave shape. The configuration of the first radiating element 94A is basically the same as the configuration of the first radiating element 74 shown in FIG. In the second radiating element 95A, of the two long edges facing the left and right of the vehicle body 1, the concave shape formed near the center of the left long edge has the shape of a home base plate. Note that the acute angle (top) of the shape of the home base plate faces rightward of the vehicle body 1.

  On the other hand, on the right long edge, a concave shape having a shape of a home base plate whose acute angle portion faces the left direction of the vehicle body 1 is formed at a position avoiding the concave shape of the left long edge. More specifically, the right long part is located between the connection part 93A provided at the boundary between the first radiating element 94A and the second radiating element 95A and the concave shape of the left long edge. The concave shape of the edge is formed. However, the position at which each concave shape is formed is not limited to this, and each concave shape may be formed at any position on each long edge as long as the purpose of extending the distance when current flows along the long edge can be achieved. it can.

  Similar to the connection portion 73 shown in FIG. 7, the connection portion 93A has an arbitrary area (region near the connection portion) where the protrusion of the first radiating element 94A and the cutout of the second radiating element 95A are fitted. Is provided at the position. One example of the position is near the upper right corner of the protrusion of the first radiating element 94A, as shown in FIG. A first feeding point 93Aa, which is one feeding point of the connecting portion 93A, is connected to the first radiating element 94A, and a second feeding point 93Ab, which is the other feeding point of the connecting portion 93A, is connected to the second feeding point 93Ab. Radiating element 95A.

  The antenna 91A is trough-folded along lines L1-L1 'and M1-M1' shown in FIG. As a result, as shown in FIG. 14, a U-shaped antenna 91A in which the dielectric film 12 is arranged on the outside and the radiating element 94A is arranged on the inside is formed. Further, the first radiating element 94A is drawn out from the first feeding point 93Aa in a downward direction (corresponding to a first direction described in claims), which is a direction intersecting the roof 20. More specifically, the first area 94Ab (near the feeding point) of the first radiating element 94A between the line L1-L1 ′ and the line M1-M1 ′ is directed downward in the vehicle body 1 (in the claims). (Corresponding to the first direction described). Further, the second region 94Aa that is continuous with the first region 94Ab is bent at an angle of 90 degrees with respect to the first region 94Ab, and is directed toward the front of the vehicle body 1.

  On the other hand, the second radiating element 95 </ b> A is a front-rear direction that is a direction along the roof 20 from the second feeding point 93 Ab and different from a downward direction of the vehicle body 1 (a second direction described in the claims). (Equivalent to). Most of the second radiating element 95A extends forward from the second feeding point 93Ab, and slightly extends rearward from the second feeding point 93Ab.

(Antenna 91B)
As shown in FIG. 15, the first radiating element 94B of the antenna 91B has the same configuration as the first radiating element 94A. The second radiating element 95B has two long edges having the above-described concave shape, but the shapes of the two concave shapes are different from the two concave shapes of the second radiating element 95A. .

  Specifically, of the two long edges of the second radiating element 95B facing in the left-right direction of the vehicle body 1, the concave shape formed on the left long edge is a home base whose apex faces the right direction of the vehicle body 1. It has a shape obtained by deforming the shape of the plate. That is, of the two sides forming the isosceles triangle on the home base plate with the top of the home base plate interposed therebetween, one side is longer than the other side and has a large opening angle with respect to the other side. Therefore, these one side and the other side correspond to two sides sandwiching the obtuse angle of the scalene triangle. Further, the one side has a direction inclined with respect to the front-rear direction of the vehicle body 1, a front-rear direction of the vehicle body 1, and a left-right direction of the vehicle body 1 in order to gain a distance when current flows along the long edge. The bending is repeated to reach the connecting portion 93B via a plurality of bending points.

  On the other hand, on the right long edge, a concave shape having a trapezoidal shape whose top is directed to the left of the vehicle body 1 is formed at a position avoiding the concave shape of the left long edge. More specifically, the right radiating element 94B and the right radiating element 95B are positioned between the connection portion 93B provided at the boundary between the first radiating element 94B and the second radiating element 95B and the concave shape of the left long edge. A long edge concave shape is formed. However, the position at which each concave shape is formed is not limited to this, and each concave shape may be formed at any position on each long edge as long as the purpose of extending the distance when current flows along the long edge can be achieved. it can. The concave shape of the left long edge may be a scalene triangle similar to the concave shape of the right long edge, and may be a scalene triangle larger than the right long edge.

  Similarly to the connection portion 93A, the connection portion 93B is provided at an arbitrary position in a region where the protrusion of the first radiating element 94B and the cutout portion of the second radiating element 95B fit (region near the connection portion). Can be A first feeding point 93Ba, which is one feeding point of the connecting portion 93B, is connected to the first radiating element 94B, and a second feeding point 93Bb, which is the other feeding point of the connecting portion 93B, is connected to the second feeding point 93Bb. Radiating element 95B.

  The antenna 91B is folded in a valley along the lines L2-L2 'and M2-M2' shown in FIG. As a result, similarly to the antenna 91A, an antenna 91B bent in a U-shape is formed. The first area 94Bb and the second area 94Ba of the first radiating element 94B correspond to the first area 94Ab and the second area 94Aa of the first radiating element 94A. The manner in which the first radiating element 94B is drawn from the first feeding point 93Ba and the manner in which the second radiating element 95B is drawn from the second feeding point 93Bb are determined by the first radiating element 94A and the second radiating element 94B. This is the same as the case of the radiating element 95A.

(Length of edge)
Next, the length of the long edge of each of the second radiating elements 95A and 95B will be described. FIG. 16 is an explanatory diagram showing the shape of the long edge provided in each of the second radiating elements 95A and 95B. As shown in FIG. 16, in the second radiating element 95A, since a current is supplied to the connection 93A, the connection 93A is a starting point of a path along the flow of the current. Also, the left and right corners of the front side edge of the second radiating element 95A are the end points 98Aa and 98Ab of the path. Similarly, also in the second radiating element 95B, the connection portion 93B becomes the starting point of the path along the current flow, and the left and right corners of the front end of the second radiating element 95B are the end points of the path. 98Ba and end point 98Bb.

  One of the two long edges of the second radiating element 95A is a long edge N1 having a length from the connecting portion 93A to the end point 98Aa, as shown by a broken line in FIG. The other of the two long edges of the second radiating element 95A is a long edge N2 having a length from the connecting portion 93A to the end point 98Ab, as shown by a dashed line in FIG. Similarly, the second radiating element 95B includes a long edge N3 having a length from the connecting portion 93B to the end point 98Ba and a long edge N4 having a length from the connecting portion 93B to the end point 98Bb.

  The length of each of the long edges N1 to N4 is set so as to satisfy a condition that the length is equal to about の of the wavelength of a low frequency (for example, 700 to 730 MHz) of the band of the electromagnetic wave radiated by the antenna. The shape and size of the concave shape formed on the long edges N1 to N4 are selected. Therefore, the shape, size, and number of the concave shapes formed on each of the long edges N1 to N4 can be arbitrarily set as long as the above conditions are satisfied.

(Characteristics of each antenna)
With the antennas 91A and 91B mounted on the vehicle body 1 as the vehicle-mounted antenna device 90 shown in FIG. 14, the radiation gain of the antennas 91A and 91B was calculated for the front side of the vehicle body 1. As a result, in the antennas 91A and 91B, the second radiating elements 95A and 95B were provided with the long edges N1 to N4, so that the entire band could be extended to the low frequency side. However, the radiation gain in the high-frequency band of the antenna 91B was better than that of the antenna 91A. Details will be described later with reference to FIGS.

(Superimposed part)
As shown in FIGS. 14 and 15, the second radiating elements 95 </ b> A and 95 </ b> B are along a spoiler fixing portion 21 d which is a metal member constituting the roof 20 and are separated from the spoiler fixing portion 21 d. Have overlapping portions 95Aa and 95Ba, respectively. The overlapping portions 95Aa and 95Ba include the tips of the second radiating elements 95A and 95B, respectively.

  Each of the superimposed portions 95Aa and 95Ba has a length Ly. The length Ly is 64.5% or less of each of the total lengths of the second radiating elements 95A and 95B, and more preferably 26.0% or more and 55.2% of each of the total lengths of the second radiating elements 95A and 95B. It is as follows.

  In the spoiler 16 ′, by configuring the length Ly to be 64.5% or less of the total length, a direction crossing the roof 20 as viewed from the spoiler 16 ′ (in the present embodiment, the front direction of the vehicle body 1). Can be made larger than when the second radiating elements 95A and 95B do not overlap the spoiler fixing portion 21d. Further, by configuring the length Ly to be 26.0% or more and 55.2% or less of the entire length, the gain of the vehicle body 1 in the forward direction can be further increased.

  The distance Dz between the second radiating elements 95A, 95B and the spoiler fixing part 21d in the overlapping parts 95Aa, 95Ba is less than 18 mm, more preferably, less than 11 mm. In the spoiler 16 ', the overlapping portions 95Aa and 95Ba overlap with the spoiler fixing portion 21d, and the interval Dz in the overlapping portions 95Aa and 95Ba is less than 18 mm. The gain can be made larger than when the second radiating elements 95A and 95B do not overlap the spoiler fixing portion 21d. Further, by configuring the distance Dz to be less than 11 mm, the gain of the vehicle body 1 in the forward direction can be further increased.

  In the present embodiment, the spoiler 16 ′ is configured so that the overlapping portions 95Aa and 95Ba overlap each other along the spoiler fixing portion 21d and in a state separated from the spoiler fixing portion 21d. 'May be fixed to the roof 20. In this case, the spoiler 16 'may be configured so that the overlapping portions Aa and 95Ba overlap with the metal member forming the rear end of the roof 20 and are separated from the metal member.

  The total lengths of the first radiating elements 94A and 94B and the total lengths of the second radiating elements 95A and 95B are not particularly limited, and the total lengths of the respective radiating elements 95A and 95B are determined according to the frequency of the electromagnetic wave to be radiated from the antennas 91A and 91B. It can be determined as appropriate. The length Ly may be determined based on the total length of the second radiating elements 95A and 95B determined according to the frequency of the electromagnetic wave to be radiated from the antennas 91A and 91B so as to fall within the above-described range.

[Fifth to seventh embodiments]
Hereinafter, fifth to seventh embodiments of the present invention will be described. The in-vehicle antenna 10 according to the fifth embodiment employs an antenna 71 shown in FIG. The on-vehicle antenna 90 according to the sixth embodiment employs an antenna 91A shown in FIG. The antenna 90 according to the seventh embodiment employs an antenna 91B shown in FIG. Each of (a) to (c) of FIG. 17 is a developed view in which the antenna 71, the antenna 91A, and the antenna 91B are developed on a plane.

  FIG. 18A is a graph illustrating the frequency dependence of the radiation gain of the vehicle-mounted antenna device 70 including the antenna 71 and the vehicle-mounted antenna device 90 including the antenna 91A. FIG. 18B is a graph showing the frequency dependence of the VSWR of the vehicle-mounted antenna device 70 having the antenna 71 and the vehicle-mounted antenna device 90 having the antenna 91A.

  FIG. 19A is a graph showing the frequency dependence of the radiation gain of the vehicle-mounted antenna device 90 having the antenna 91A and the vehicle-mounted antenna device 90 having the antenna 91B. FIG. 19B is a graph showing the frequency dependence of the VSWR of the radiation gain of the vehicle-mounted antenna device 90 having the antenna 91A and the vehicle-mounted antenna device 90 having the antenna 91B.

  The radiation gains and VSWR of the vehicle-mounted antenna devices 70 and 90 were measured with each of the vehicle-mounted antenna devices 70 and 90 mounted on the rear end of the roof 20 of the vehicle body 1. The radiation gain of each of the in-vehicle antenna devices 70 and 90 shown in FIGS. 18A and 19A is the radiation gain in a plane along the roof 20 of the vehicle body 1 and the antennas 71, 91A and 91B. This is a value obtained by calculating for all directions at the center and summing up all directions.

  Referring to FIG. 18A, the radiation gain of the vehicle-mounted antenna device 90 having the antenna 91A is smaller than the radiation gain of the vehicle-mounted antenna device 70 having the antenna 71 in a frequency band of less than 0.8 GHz. You can see that it exceeds.

  Referring to FIG. 18B, the VSWR of the vehicle-mounted antenna device 90 including the antenna 91A is lower than the VSWR of the vehicle-mounted antenna device 70 including the antenna 71 in a frequency band of less than 0.8 GHz. You can see that there is.

  This is an effect obtained by forming a concave shape on the second radiating element 95A of the antenna 91A. That is, by configuring the edge length of the antenna 95A to be longer than the edge length of the antenna 71, the band of the vehicle-mounted antenna device 90 could be expanded to a lower frequency side as compared with the band of the vehicle-mounted antenna device 70. .

  Referring to FIG. 19A, the radiation gain of the vehicle-mounted antenna device 90 having the antenna 91B exceeds the radiation gain of the vehicle-mounted antenna device 90 having the antenna 91A in the frequency band near 2 GHz. You can see that there is.

  Referring to FIG. 19B, the VSWR of the on-vehicle antenna device 90 provided with the antenna 91B is equal to the VSWR of the on-vehicle antenna device 90 provided with the antenna 91A in the frequency band of 1.7 GHz or more and 2.3 GHz or less. It turns out that it is lower than VSWR.

  As described above, it has been found that the in-vehicle antenna device 90 having the antenna 91B has better characteristics in the high frequency band than the in-vehicle antenna device 90 having the antenna 91A.

[Further modification of antenna]
Hereinafter, modified examples of the antenna 71 shown in FIG. 7 will be described with reference to FIGS. FIG. 20 is a developed view in which an antenna 71A, which is a modified example of the antenna 71, is developed on a plane. FIG. 21A is a plan view obtained when the antenna 71A bent in a U-shape is viewed from a direction perpendicular to the second radiating element 75A. FIG. 21B is a right side view of the antenna 71 shown in FIG. FIG. 21C is a cross-sectional view taken along the line XX ′ shown in FIG. 21A. FIG. 22A is a developed view in which an antenna 71B which is another modified example of the antenna 71 is developed on a plane. FIG. 22B is a plan view obtained when the antenna 71B bent in a U-shape is viewed from a direction perpendicular to the second radiating element 75B.

(Antenna 71A)
In the antenna 71A, the first radiating element 74 included in the antenna 71 is replaced with a first radiating element 74A, and the second radiating element 75 included in the antenna 71 is replaced with a second radiating element 75A. Obtained by

  As shown in FIG. 20, the first radiating element 74A is connected to one conductor of a coaxial line (not shown) at one feeding point 73Aa, and includes a region including the one feeding point 73Aa and an NN ′ line. From the feed point 74Aa (the first portion described in the claims), which is a region from the OO 'line to the OO' line, and the end of the first radiating element 74A from the OO 'line (the side opposite to the connection portion 73A). The second portion 74Ab which is a region up to the end of the second portion 74Ab). The power supply point neighboring portion 74Aa is a portion drawn from the one power supply point 73Aa in the first direction.

  The second radiating element 75A is connected to the other conductor of the coaxial cable (not shown) at the other feeding point 73Ab, and includes a root 75Aa including the other feeding point 73Ab, a branch 75Ab, a neck 75Ac, and a 75Ad.

  The antenna 71A is trough-folded along the NN ′ line and the OO ′ line shown in FIG. 20, and has a first plane P1 along a first direction, a second plane P2 along a second direction, And a first plane P1, and is bent in a U-shape along a third plane P3 facing the second plane P2. As a result, as shown in FIG. 21, a U-shaped antenna 71A in which the dielectric film 72 is disposed on the outside and the first and second radiating elements 74A and 75A are disposed on the inside is formed. .

  In a state of being bent into a U-shape, the connection portion 73A constituted by the feeding points 73Aa and 73Ab is arranged on the third plane P3 and near the intersection that intersects the first plane P1.

(First radiating element 74A)
In the first radiating element 74A, the feed point vicinity 74Aa is arranged on the first plane P1, and the second portion 74Ab is arranged on the third plane P3. The second radiating element 75A is arranged on the second plane P2. In the present modification, each of the second plane P2 and the third plane P3 is orthogonal to the first plane P1. That is, the second plane P2 and the third plane P3 are parallel to each other. Each of the first plane P1, the second plane P2, and the third plane P3 respectively corresponds to the first plane, the second plane, and the third plane described in the claims. In this modification, a plane is adopted as each of the first, second, and third surfaces, but a curved surface may be adopted as each of the first, second, and third surfaces. . Further, the second surface and the third surface need not be parallel to each other.

  The second portion 74Ab of the first radiating element 74A is configured by a first linear portion extending in one direction from an end of the feeding point vicinity 74Aa. The one direction is a direction along the third plane P3 and away from the second plane P2. In the present modification, the first plane P1 and the third plane P3 are parallel, so that the direction coincides with the second direction.

(Second radiating element 75A)
As described above, the second radiating element 75A is connected to the other feeding point 73Ab, and includes the root part 75Aa, the branch part 75Ab, the neck part 75Ac, and the main part 75Ad.

  The root part 75Aa extends in the second direction from the other feeding point 73Ab on the second plane P2, and extends in a third direction (a direction parallel to the illustrated XX ′ line) intersecting the second direction. Is a conductor configured so that the width of the first radiating element 74A is smaller than the width of the first radiating element 74A near the feeding point 74Aa. Since the width of the root portion 75Aa in the third direction is configured to be narrower than the first portion 74Aa of the first radiating element 74A, the second portion extended from the first portion 74Aa of the first radiating element 74A. The portion 74Ab (first linear portion) and the base portion 75Aa of the second radiating element can be arranged so as not to overlap.

  The branch portion 75Ab is a band-shaped conductor extending in the third direction from the root portion 75Aa on the second plane P2. The length of the second portion 74Ab extending from the first radiating element 74A and the length of the branch portion 75Ab extending from the root portion 75Aa are determined so as not to overlap with each other.

  The neck portion 75Ac is a band-shaped conductor that extends in the second direction from the end of the root portion 75Aa in the second plane P2, and has a smaller width in the third direction than the root portion 75Aa.

  The main portion 75Ad is a conductor provided at an end of the neck 75Ac and having an elliptical shape.

  As shown in FIG. 21A, when viewed in a plan view from a direction orthogonal to the third plane P3, the second portion 74Ab is provided with a feed point 73Aa of the first radiating element 74A arranged on the second plane P2. Are configured so as not to overlap. Also, the second portion 74Ab does not overlap with the second radiating element 75A.

(Effect of antenna 71A)
For example, the antenna 11 can be mounted in a small space by bending it into a U-shape. On the other hand, the inventors of the present application have found that the radiation characteristics of the antenna deployed in a plane and the antenna folded in a U-shape change, and the radiation characteristics of the antenna deployed in a plane are more U-shaped. It has been found that the radiation characteristics of the antenna bent in a mold deteriorate.

  The antenna 71A employs a configuration in which the second portion 74Ab of the first radiating element 74A does not overlap with the feed point 73Aa of the first radiating element 74A, and thus the above-described deterioration (caused by bending the antenna into a U-shape). Deterioration) can be suppressed. This is because the capacitance generated between the bent first radiating elements 74A, that is, the capacitance generated between the second portion 74Ab and the one feeding point 73Aa can be suppressed.

  Moreover, the above-described deterioration can be further suppressed by adopting a configuration in which the antenna 71A does not overlap with the second radiating element 75A. This is because the capacitance generated between the second portion 74Ab provided on each of the second plane P2 and the third plane P3 facing each other and the second radiating element 75A can be suppressed.

  In the antenna 71, a change in the input characteristics of the antenna caused by bending the antenna into a U-shape is canceled by appropriately overlapping a part of the antenna 71 with the end of the roof 20 of the vehicle body 1. Therefore, when the antenna 71 is used, the input characteristics of the antenna are sensitive to the installation position of the antenna 71 with respect to the vehicle body 1 (roof 20), which is disadvantageous when the antenna 71 is installed in various vehicles. . In the antenna 71A, since the above-described deterioration (deterioration caused by bending the antenna into a U-shape) can be suppressed, the antenna bent into a U-shape is disposed at the end of the roof 20 of the vehicle body 1. Therefore, there is an advantage that the change in input characteristics due to the above is small and the device can be used for general purposes.

  It is known that the impedance matching between the coaxial line connected to the connection portion 73A and the antenna 71A depends on the capacitance generated between the first radiating element 74A and the second radiating element 75A. The antenna 71A configured as described above improves the impedance matching as compared with the case where the capacitance generated between the first radiating element and the second radiating element is generated only in the feeding region, The radiation characteristics of the antenna can be further improved.

  Further, compared to a radiating element having a rectangular main part, the VSWR characteristic band on the low frequency side of the frequency band in which the antenna 71A operates can be expanded by the elliptical shape of the main part 75Ad. it can.

(Interval between the second plane P2 and the third plane P3)
From the viewpoint of making the space for mounting the antenna 11 compact, it is preferable that the distance between the second plane P2 and the third plane P3, in other words, the distance between the OO 'line and the NN' line be smaller. preferable. Hereinafter, this interval is referred to as the height h of the antenna 11 (see FIG. 21B).

  However, as the height h decreases, the distance d between the root portion 75Aa of the second radiating element 75A and the second portion 74Ab of the first radiating element 74A (the cross-sectional arrow in FIG. 21C). (See the view).

  Even if a configuration in which the second portion 74Ab and the second radiating element 75A do not overlap with each other is adopted, if the distance d is excessively small, the second portion 74Ab and the base portion 75Aa of the second radiating element 75A may not be overlapped. The capacitance generated between them may increase, and the radiation characteristics of the antenna deteriorate.

  The inventors of the present application have a configuration in which the distance d is 1/20 or more, more preferably 1/16 or more, of the wavelength of the electromagnetic wave having the resonance frequency of the second portion 74Ab in a vacuum, so that the radiation characteristic is improved. It has been found that deterioration can be sufficiently suppressed.

  Further, since the second radiating element 75A includes the neck portion 75Ac, even when a coaxial line is arranged near the second radiating element 75A, interference caused by the coaxial line to the antenna device 71A is suppressed. can do. Therefore, it is possible to suppress the deterioration of the radiation characteristics caused by bending the antenna 71 into a U-shape. The operating band (mainly on the low frequency side) of the antenna 71A can be adjusted by appropriately adjusting the size of the neck 75Ac.

(Antenna 71B)
In the antenna 71B, the first radiating element 74 included in the antenna 71 is replaced with a first radiating element 74B, and the second radiating element 75 included in the antenna 71 is replaced with a second radiating element 75B. Obtained by

  As shown in FIG. 22A, the first radiating element 74B is connected to one feed point 73Ba, and is in the vicinity of the feed point which is a region from the PP ′ line to the QQ ′ line. 74Ba (the first portion described in the claims) and the second portion 74Bb, which is a region from the QQ 'line to the end of the first radiating element 74A (the end opposite to the connection portion 73B). The third portion 74Bd is provided.

  The second radiating element 75B is connected to the other feeding point 73Bb, and includes a root portion 75Ba, a narrow neck portion 75Bc, and a main portion 75Bd.

  The antenna 71B is folded in a valley along a line PP ′ and a line QQ ′ shown in FIG. 22A, a first plane P1 along a first direction, and a first plane P1 along a second direction. It is bent in a U-shape so as to intersect the two planes P2 and the first plane P1 and to extend along a third plane P3 facing the second plane P2. As a result, as shown in FIG. 22B, a U-shaped antenna 71B in which the dielectric film 72 is disposed on the outside and the first and second radiating elements 74B and 75B are disposed on the inside. Is formed.

  The second portion 74Bb of the first radiating element 74B includes a first linear portion extending in one direction from an end of the feeding point vicinity portion 74Aa, and an end portion of the first linear portion (feeding point vicinity portion 74Aa). And the second straight portion extending from the end opposite to the first straight portion. The one direction is a direction along the third plane P3 and away from the second plane P2. In the present modified example, the first plane P1 and the third plane P3 are parallel to each other, so that the direction coincides with the second direction.

  The third portion 74Bd of the first radiating element 74B is configured by a first linear portion extending in one direction from an end of the feeding point vicinity 74Aa.

  The second radiating element 75B is connected to the other feeding point 73Bb, and includes a root part 75Ba, a neck part 75Bc, and a main part 75Bd.

  Each of the root portion 75Ba and the neck portion 75Bc is configured similarly to the root portion 75Aa and the neck portion 75Ac of the antenna 71A, respectively.

  The main portion 75Bd is provided at an end of the neck portion 75Bc, and alternately arranges the region 75Bd1 extended in the second direction and the region 75bd2 extended in the direction along the third direction. It has a meandering configuration.

  In this modification, a configuration is adopted in which the region 75bd2 is first connected to the end of the neck portion 75Bc, and then two regions 75Bd1 and 75Bd2 are arranged. However, which of the region 75Bd1 and the region 75Bd2 is arranged at the end of the neck portion 75Bc, or how many sets of the region 75Bd1 and the region 75Bd2 are arranged can be determined as appropriate.

  As shown in FIG. 22B, when the second part 74Bb of the first radiating element 74B is viewed in a plan view from a direction perpendicular to the third plane P3, the second part 74Bb and the third part 74Bd It is configured not to overlap the feed point 73Ba of one radiating element 74B. The second portion 74Bb does not overlap with the second radiating element 75B except for a tip region 74Bc which is an end opposite to the first portion 74Ba.

  When the second portion 74Bb of the first radiating element 74B is viewed in a plan view from a direction perpendicular to the third plane P3, the antenna 71B configured as described above includes the first portion 74Bb and the third portion 74Bd that are the first portion. Is configured not to overlap with the feed point 73Ba of the radiating element 74B, and thus has the same effect as the antenna 71A. In addition, since the main portion 75Bd has a meandering shape, the edge length of the second radiating element 75B is increased while the element length of the second radiating element 75B (from the PP ′ line to the second radiating element 75B) is increased. (The length up to the end of the end) can be suppressed. Therefore, the antenna 71B can be made more compact.

  In the antenna 71B, the tip region 74Bc of the first radiating element 74B is overlapped with the second radiating element 75B, so that impedance matching can be improved.

[Eighth embodiment]
FIG. 23A is a graph illustrating the frequency dependency of the VSWR of the vehicle-mounted antenna device 70 including the antenna 71 according to the fifth embodiment. The solid line indicates the VSWR measured before the antenna 71 was bent into a U-shape, that is, when the antenna 71 was developed on a plane. The broken line indicates the VSWR measured when the antenna 71 is bent in a U-shape. The dotted line shows the VSWR measured in a state where the antenna 71 bent in a U-shape is superimposed on a metal plate.

  FIG. 23B is a graph illustrating the frequency dependence of the VSWR of the vehicle-mounted antenna device 70 (the eighth embodiment) including the above-described antenna 71A. Each of the solid line, the broken line, and the dotted line represents a state in which the antenna 71A is expanded, a state in which the antenna 71A is bent into a U-shape, and a state in which the antenna 71A is bent, as in the case of (a). The VSWR measured in a superimposed state is shown.

  The metal plate simulates a roof when the vehicle-mounted antenna device is mounted on a vehicle body. Therefore, the VSWR obtained when each of the vehicle-mounted antenna devices 70 according to the fifth and eighth embodiments is actually operated is considered to be closest to the VSWR indicated by the dotted line.

  Referring to FIG. 23 (a), the antenna 71 is in a deployed state, a U-shaped bent state, and a state of being superimposed on a metal plate. It can be seen that the frequency dependence greatly changes the shape.

  On the other hand, referring to FIG. 23B, the antenna 91B is in an unfolded state, a state of being bent into a U-shape, and a state in which the antenna 91B is superimposed on a metal plate. It can be seen that the frequency dependence of the measured VSWR is stable and its shape is hardly changed.

  As described above, as compared with the antenna 71, it was found that the antenna 71A can suppress the deterioration of the radiation characteristic caused by bending the antenna into a U-shape. In addition, as compared with the antenna 71, it was found that the antenna 71A can suppress deterioration of radiation characteristics that can occur when the antenna folded in a U-shape is superimposed on a metal plate.

  Therefore, the antenna 71A can easily perform an adjustment step of adjusting (optimizing) the antenna pattern while feeding back the measured radiation characteristics. This is because there is a small difference between the radiation characteristics obtained in the expanded state and the radiation characteristics obtained in operation, so that the antenna pattern can be adjusted using the radiation characteristics in the expanded state.

  The present invention is not limited to the embodiments described above, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

  INDUSTRIAL APPLICATION This invention can be utilized for the vehicle-mounted antenna apparatus arrange | positioned at the edge part of the roof of a vehicle body.

1 vehicle body 10, 30, 60, 90, 110 vehicle-mounted antenna device 11, 31, 41, 51, 61, 71, 71A, 71B, 81, 91A, 91B, 111 antenna 12, 32, 42, 52, 62, 72 , 82, 112 Dielectric films 13, 33, 43, 53, 63, 73, 83, 93A, 93B, 113 Connection portions 13a, 33a, 43a, 53a, 63a, 73a, 73Aa, 73Ba, 83a, 93Aa, 93Ba, 113a 1st feeding point (one feeding point)
13b, 33b, 43b, 53b, 63b, 73b, 73Ab, 73Bb, 83b, 93Ab, 93Bb, 113b Second feeding point (the other feeding point)
14, 34, 64, 74, 74A, 74B, 94A, 94B, 114 First radiating elements 14a, 34a, 64a, 74a, 74Aa, 74Ba, 85a, 114a Near the feed point (drawn out in the first direction). Part)
15, 35, 65, 75, 75A, 75B, 95A, 95B, 115 Second radiating element 15a, 55a, 75a, 86a, 115a Near feed point (portion drawn in second direction)
16, 16 ', 66, 116 Spoiler 20 Roof 21 Hatch gate 21a Hatch gate panel 21b Rear glass 21c Frame 21d Spoiler fixing portion (antenna device fixing portion)
35b, 44b, 54b, 65b, 75b, 84b, 95Aa, 95Ba Superimposed part 44, 54, 84 Radiating element 55, 85 First conductor (radiating element)
56, 86 Second conductor (radiating element)
57,87 Third conductor (radiating element)
P1 1st plane (1st plane)
P2 2nd plane (2nd plane)
P3 Third plane (third plane)

Claims (11)

In a vehicle-mounted antenna device arranged at an end of a roof of a vehicle body,
Among the pair of feeding points, a first radiating element drawn from one feeding point in a first direction and a second radiating element drawn from the other feeding point in a second direction different from the first direction. comprising a antenna having a radiating element of including a radiating element,
The first direction, up direction der intersecting the horizontal plane when the vehicle antenna apparatus mounted on the vehicle body,
The first radiating element has a first portion arranged on a first surface intersecting the horizontal plane, and a second portion arranged on a second surface intersecting the first surface,
The second radiating element, along the horizontal plane, Ru is and disposed on the third surface on the opposed to the second surface,
An in-vehicle antenna device, comprising: The second direction is a direction crossing the horizontal plane when the vehicle-mounted antenna device is mounted on the vehicle body.
The in-vehicle antenna device according to claim 1, wherein: The second direction is a direction along the horizontal plane when the vehicle-mounted antenna device is mounted on the vehicle body.
The in-vehicle antenna device according to claim 1, wherein: The radiating element further includes an overlapping portion that overlaps with a metal member that constitutes the end of the roof and that is overlapped with the metal member while being separated from the metal member.
The in-vehicle antenna device according to any one of claims 1 to 3, wherein: The width of the portion of the radiating element that is drawn out from the one feeding point in the first direction is equal to or less than half the shortest wavelength of the electromagnetic wave radiated by the antenna.
The in-vehicle antenna device according to any one of claims 1 to 4, wherein: At least one of a width of a portion of the radiating element that is drawn from the one feeding point in the first direction and a width of a portion of the radiating element that is drawn from the other feeding point in the second direction. Either one is １ ／ or less of the shortest wavelength of the electromagnetic wave radiated by the antenna,
The in-vehicle antenna device according to claim 2, wherein: The antenna is a dipole antenna including a first radiating element and a second radiating element.
The in-vehicle antenna device according to any one of claims 1 to 6, wherein: The in-vehicle antenna device is disposed at a front end or a rear end of the roof, and a width of the radiating element measured along a front end or a rear end of the roof is equal to a width of the antenna. Less than half the shortest wavelength of the electromagnetic wave,
The in-vehicle antenna device according to claim 7, wherein: The second radiating element has a shape in which a notch or a concave shape is formed with respect to a long side of the rectangle.
The in-vehicle antenna device according to claim 8, wherein: The one feeding point is located on the third surface, near an intersection with the first surface,
When the radiating element is viewed in a plan view from a direction orthogonal to the third surface, the one feeding point and the second portion do not overlap,
The in-vehicle antenna device according to claim 9 , wherein: The in-vehicle antenna device has a spoiler as a housing,
The vehicle-mounted antenna device according to any one of claims 1 to 10 , wherein:

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