WO2018110463A1

WO2018110463A1 - Antenna device

Info

Publication number: WO2018110463A1
Application number: PCT/JP2017/044241
Authority: WO
Inventors: 威山保; 清二郷; 拓也遊馬
Original assignee: 株式会社ヨコオ
Priority date: 2016-12-16
Filing date: 2017-12-08
Publication date: 2018-06-21
Also published as: JP6960942B2; JPWO2018110463A1

Abstract

Provided is an antenna device capable of intensifying directionality in a direction that is parallel to a ground plane. An antenna device 1 is provided with a ground plane 5 and an antenna element 10. The antenna element 10 includes a first margin section 15, a second margin section 16, a third margin section 17, and a fourth margin section 18 that that are integrated to form a whole which is approximately parallel to the ground plane 5. A first connecting section 11 and a second connecting section 12 extend respectively from the first margin section 15 and the second margin section 16, which are opposite to each other, and the second connecting section 12 is connected to the ground plane 5. A crosslinking section 19 is provided so as to link the third margin section 17 and the fourth margin section 18, which are opposite to each other.

Description

Antenna device

The present invention relates to an antenna device in which an antenna element makes a round substantially parallel to a ground conductor plate.

2. Description of the Related Art In recent years, for example, an LTE (Long Term Evolution) antenna device mounted on a roof of a vehicle or inside an instrument panel, an antenna device configured to be capable of transmitting and receiving a wideband frequency and having a low profile has been developed. is needed.

When the antenna element is configured to make a round substantially parallel to the ground conductor plate, the loop length of the antenna element is n × λ (where n is a natural number and when n = 1, the antenna element operates as a folded antenna). In terms of frequency, there is a problem that the directivity is biased in the direction perpendicular to the ground conductor plate, and the directivity in the direction parallel to the ground conductor plate is weakened.

The present invention has been made in recognition of such a situation, and an object of the present invention is to provide an antenna device capable of enhancing directivity in a direction parallel to the ground conductor plate.

One embodiment of the present invention is an antenna device. This antenna device
A ground conductor plate and an antenna element;
The antenna element includes a circular portion that goes around substantially parallel to the ground conductor plate, a first connection portion that extends from the circular portion, and has an end portion as a feeding point, the circular portion, and the ground conductor plate. A second connecting portion that electrically connects the two, and a bridging portion that divides the internal region of the circulating portion,
Both ends of the bridging portion are electrically connected to the rotating portion at positions separated from the first and second connecting portions by a predetermined distance or more.

The predetermined distance may be 1/8 or more of the circuit length of the circuit part.

The circumferential portion has first to fourth sides and circulates in a rectangular shape, and the first and second connecting portions extend from the first and second sides facing each other of the circumferential portion, respectively. The bridging portion may be provided so as to pass the third and fourth sides to each other.

The bridging portion may pass between the middle points of the third and fourth sides.

The circumferential portion may be along the outer edge of the ground conductor plate when viewed from a direction perpendicular to the ground conductor plate.

The antenna element may include a third connection portion that electrically connects the bridging portion and the ground conductor plate to each other, and an end portion of the third connection portion may be grounded.

The second connection portion may be plate-shaped.

The first and second connecting portions may extend from a pair of diagonal portions of the circulating portion.

The antenna element may be for LTE.

It should be noted that an arbitrary combination of the above-described components and a conversion of the expression of the present invention between methods and systems are also effective as an aspect of the present invention.

According to the present invention, it is possible to provide an antenna device capable of enhancing directivity in a direction parallel to the ground conductor plate.

The schematic perspective view which looked at the antenna apparatus 1 which concerns on Embodiment 1 of this invention from the front diagonally upper side. The schematic perspective view which looked at the antenna apparatus 1 from back diagonally upward. The schematic perspective view which abbreviate | omitted the housing | casing 4 in FIG. The schematic perspective view which abbreviate | omitted the housing | casing 4 in FIG. The schematic perspective view which abbreviate | omitted the base 3 in FIG. The schematic perspective view which abbreviate | omitted the base 3 in FIG. The schematic perspective view of the antenna element of the antenna apparatus which concerns on the comparative example 1. FIG. The schematic perspective view of the antenna element of the antenna apparatus which concerns on the comparative example 2. FIG. The graph which shows the frequency characteristic of the gain of the horizontal direction (direction parallel to the ground conductor board 5) in each of the antenna apparatus 1 of Embodiment 1, and the antenna apparatus of Comparative Examples 1 and 2. The graph which shows the frequency characteristic of VSWR of the antenna apparatus 1 with the frequency characteristic of VSWR when the 3rd connection part 13 is lose | eliminated from the antenna apparatus 1. FIG. The schematic perspective view which looked at the antenna apparatus 801 which concerns on the comparative example 3 from back diagonally upward. 10 is a graph showing frequency characteristics of gain with respect to vertical polarization in the horizontal direction in each of antenna apparatus 1 according to Embodiment 1 and antenna apparatus 801 according to Comparative Example 3. The schematic perspective view which looked at the antenna apparatus 1a which concerns on Embodiment 2 of this invention from the front diagonally upper side. 6 is a graph showing the frequency characteristics of the VSWR of the antenna device 1a together with the frequency characteristics of the VSWR of the antenna device 1 of the first embodiment. The schematic perspective view which looked at the antenna apparatus 1b which concerns on Embodiment 3 of this invention from the front diagonally upper side. FIG. 20 is a schematic perspective view of the antenna device 1b in which the front waterproof pad 62 and the front base cover 63 are omitted from FIG. 15, and is a perspective view for explaining a cut surface of the cross-sectional views shown in FIGS. The disassembled perspective view of the antenna apparatus 1b. Sectional drawing of the antenna apparatus 1b cut | disconnected by the AA line of FIG. Sectional drawing of the antenna apparatus 1b cut | disconnected by the BB line of FIG. The lower perspective view of the disassembled state of the movable base 60 and the front fixed base 61 shown in FIG. FIG. Sectional drawing cut | disconnected in the front-back direction which shows the fixing process of the antenna apparatus 1b by the front volt | bolt 51 and the nut 52. FIG. The lower perspective view of the antenna case 2. FIG. The lower perspective view of the antenna case 2 with the outer pad 80 attached. The bottom view. CC sectional drawing of FIG. DD sectional drawing of FIG. FIG. 4 is an enlarged cross-sectional view of the vicinity of a mutual contact portion between an outer pad 80 and a vehicle roof 200. FIG. 4 is an enlarged cross-sectional view of the vicinity of a mutual contact portion between the outer pad 80 and the vehicle roof 200 when the outer pad 80 has a folded portion 85.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same or equivalent component, member, etc. which are shown by each drawing, and the overlapping description is abbreviate | omitted suitably. In addition, the embodiments do not limit the invention but are exemplifications, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

(Embodiment 1)
An antenna apparatus 1 according to Embodiment 1 of the present invention will be described with reference to FIGS. With reference to FIG. 1, the front and rear, top and bottom, and left and right directions are defined. The antenna device 1 targets transmission and reception of 699 to 960 MHz and 1710 to 2690 MHz. The antenna device 1 includes a base 3, a housing 4, a ground conductor plate 5, a substrate 7, and an antenna element 10. The base 3 is made of aluminum, for example, and holds the ground conductor plate 5 and the housing 4. The housing 4 is an insulating resin molded body fixed to the upper surface of the base 3, holds the antenna element 10, and covers the upper surface of the ground conductor plate 5 and the substrate 7. The ground conductor plate 5 is a flat plate that is provided on the upper surface of the base 3 and functions as the ground of the antenna element 10 and is parallel to the front-rear and left-right directions. An opening 5 a for allowing a coaxial cable (not shown) to pass through is provided at a substantially central portion of the ground conductor plate 5. The substrate 7 is provided at the right front end of the upper surface of the ground conductor plate 5. The substrate 7 is for feeding power to the antenna element 10 and is connected to a core wire of a coaxial cable (not shown) that has passed through the opening 5a.

The antenna element 10 is for LTE (Long Term Evolution) and is made of a conductor, and includes a first connecting portion 11, a second connecting portion 12, a third connecting portion 13, a first side portion 15, and a second side portion 16. , The third side portion 17, the fourth side portion 18, and the bridging portion 19. The first connection portion 11, the second connection portion 12, and the third connection portion 13 each rise substantially vertically (upward) from the ground conductor plate 5. The lower end portion of the first connection portion 11 is connected to the substrate 7 and serves as a feeding point. The lower ends of the second connection portion 12 and the third connection portion 13 are connected to the ground conductor plate 5 (grounded). In addition, the shape of the 1st connection part 11, the 2nd connection part 12, and the 3rd connection part 13 may mutually differ, and may be the same.

The first side portion 15, the second side portion 16, the third side portion 17, and the fourth side portion 18 are flat plates that are substantially parallel to the ground conductor plate 5, and form rectangular (here rectangular) sides. And the surrounding part which makes a round substantially parallel to the ground conductor board 5 is comprised. This circulating portion is along the outer edge of the ground conductor plate 5 when viewed from above. The first connection portion 11 extends downward from the right front end portion of the first side portion 15. The widths of the first side portion 15, the second side portion 16, the third side portion 17, and the fourth side portion 18 may be the same or different. The first connection portion 11 electrically connects the right front end portion of the first side portion 15 and the substrate 7 to each other. The second connection portion 12 extends downward from the left rear end portion of the second side portion 16 facing the first side portion 15. The second connection portion 12 is electrically connected to the left rear end portion of the second side portion 16 and the ground conductor plate 5. The 1st connection part 11 and the 2nd connection part 12 are each extended from a pair of diagonal part of the said circumference | surroundings part.

The length along the antenna element 10 from the feeding point at the lower end of the first connecting part 11 to the ground point at the lower end of the second connecting part 12 (the grounding point between the second connecting part 12 and the ground conductor plate 5). Is preferably ½ or more of the wavelength of 699 MHz, in either case, whether near or far from the feeding point at the lower end of the first connection portion 11. Thereby, the antenna element 10 can preferably transmit and receive a frequency of 699 to 960 MHz.

The height of the first connection portion 11 in the vertical direction is preferably ¼ or less of the wavelength in the frequency band of 1710 MHz to 2690 MHz. Thereby, the antenna element 10 can preferably transmit and receive a frequency of 1710 to 2690 MHz.

The first connection portion 11 is a plate-like conductor that extends along the first side portion 15 and is parallel to the length direction (left-right direction) of the first side portion 15 and perpendicular to the width direction (front-rear direction). The second connection portion 12 is a plate-like conductor that extends along the second side portion 16 and is parallel to the length direction (left-right direction) of the second side portion 16 and perpendicular to the width direction (front-rear direction).

A bridging portion 19 is provided between the third side portion 17 and the fourth side portion 18 facing each other. The bridging portion 19 is a flat plate that is substantially parallel to the ground conductor plate 5, and here, the vicinity of the midpoints of the third side portion 17 and the fourth side portion 18 (midpoints in the illustrated example) are electrically connected to each other. The internal regions of the first side portion 15, the second side portion 16, the third side portion 17, and the fourth side portion 18 are divided into two. The vicinity of the midpoint refers to, for example, a range of 20% of the total length of the side portion with the midpoint as the center. The width of the bridging portion 19 may be the same as or different from the widths of the first side portion 15, the second side portion 16, the third side portion 17, and the fourth side portion 18. Both ends of the bridging portion 19 are electrically connected to the third side portion 17 and the fourth side portion 18 at positions separated from the upper ends of the first connection portion 11 and the second connection portion 12 by a predetermined distance or more, respectively. The predetermined distance is preferably 1/8 or more of the circuit length of the peripheral circuit including the first side portion 15, the second side portion 16, the third side portion 17, and the fourth side portion 18. The third connection portion 13 electrically connects the bridging portion 19 and the ground conductor plate 5 to each other. The third connection unit 13 has a role of impedance matching.

FIG. 7 is a schematic perspective view of the antenna element of the antenna device according to Comparative Example 1. FIG. 8 is a schematic perspective view of an antenna element of the antenna device according to Comparative Example 2. The antenna element of Comparative Example 1 shown in FIG. 7 is a circuit comprising the first side part 15, the second side part 16, the third side part 17, and the fourth side part 18 of the antenna element 10 of the first embodiment. The portion is replaced with a rectangular top surface portion 23 with the outer edge as it is (the inner region of the circulating portion is filled with a conductor). The antenna element of Comparative Example 2 shown in FIG. 8 is obtained by eliminating the bridging portion 19 and the third connecting portion 13 from the antenna element 10 of the first embodiment. The antenna devices of Comparative Examples 1 and 2 have the same configuration as the antenna device 1 of the first embodiment except that the shape of the antenna element is different.

FIG. 9 is a graph showing the frequency characteristics of the gain in the horizontal direction (the direction parallel to the ground conductor plate 5) in each of the antenna device 1 of the first embodiment and the antenna devices of Comparative Examples 1 and 2. As is clear from FIG. 9, in the antenna device of Comparative Example 1, the average gain in the horizontal direction is generally low at 1710 to 2690 MHz. In Comparative Example 2, the average gain in the horizontal direction is low at 1710 to 2300 MHz, and a large drop in average gain is seen particularly in the vicinity of 2000 MHz. On the other hand, the antenna device 1 according to the present embodiment maintains a high average gain as a whole at 1710 to 2690 MHz. This is because, in the antenna element of Comparative Example 2, the directivity is perpendicular to the ground conductor plate at a frequency where the circulation length of the circulation portion that circulates substantially parallel to the ground conductor plate 5 is n × λ (n is a natural number). In the antenna element 10 of the present embodiment, the bridging portion 19 is provided, so that the directivity in the direction parallel to the ground conductor plate is weakened. This is because the generation of standing waves is suppressed and the directivity in the direction parallel to the ground conductor plate 5 is enhanced.

FIG. 10 is a graph showing the frequency characteristics of the VSWR of the antenna device 1 together with the frequency characteristics of the VSWR when the third connection unit 13 is omitted from the antenna device 1. In FIG. 10, the solid line indicates the VSWR frequency characteristic of the antenna device 1 of the present embodiment, and the broken line indicates the VSWR frequency characteristic when the third connecting unit 13 is omitted from the antenna device 1. As shown in FIG. 10, by providing the third connecting portion 13, the VSWR at 800 to 1500 MHz can be remarkably improved.

FIG. 11 is a schematic perspective view of the antenna device 801 according to the comparative example 3 as seen from the obliquely upper rear side. The antenna element 810 of the antenna device 801 is different from the antenna element 10 of the antenna device 1 according to Embodiment 1 in that the plate-like second connection portion 12 is replaced with a rod-like second connection portion 812. The other points are the same. In addition, the position of the lower end part of the 2nd connection part 812 is the same as the position of the part farthest from the feeding point of the lower end part of the 1st connection part 11 among the lower end parts of the 2nd connection part 12 in Embodiment 1. FIG. .

FIG. 12 is a graph showing frequency characteristics of gain with respect to vertical polarization in the horizontal direction in each of the antenna device 1 according to the first embodiment and the antenna device 801 according to the comparative example 3. In FIG. 12, the solid line indicates the frequency characteristic of the gain of the antenna device 1 of the present embodiment, and the broken line indicates the frequency characteristic of the gain of the antenna device 801 of the comparative example 3. From FIG. 12, it is possible to improve the gain in both the frequency band of 699 MHz to 960 MHz and the frequency band of 1710 to 2690 MHz compared to the case of the rod shape because the second connection portion 12 is plate-shaped.

According to this embodiment, the following effects can be achieved.

(1) Since the saddle antenna element 10 has the bridging portion 19, it is possible to suppress the occurrence of a specific standing wave in the antenna element 10 and to enhance the directivity in the direction parallel to the ground conductor plate 5. .

(2) Since the saddle antenna element 10 has the third connecting portion 13 that connects the bridging portion 19 and the ground conductor plate 5 to each other, the impedance of the feeding point is lowered, and the VSWR can be improved.

(Embodiment 2)
FIG. 13 is a schematic perspective view of the antenna device 1a according to the second embodiment of the present invention as viewed from the diagonally upper front side. Compared with the antenna element 10 of the first embodiment, the antenna element 10 of the present embodiment has the second connecting portion 12a extending downward from the vicinity of the center of the second side portion 16, and the fourth connecting portion 21. Is different in that it is added, and the other points are the same. The fourth connecting portion 21 is bent from the inner edge of the end portion of the fourth side portion 18 on the second side portion 16 side and extends downward, and the lower end portion is connected to the ground conductor plate (grounded).

FIG. 14 is a graph showing the frequency characteristics of the VSWR of the antenna device 1a together with the frequency characteristics of the VSWR of the antenna device 1 of the first embodiment. From FIG. 14, the antenna device 1 a can obtain a good VSWR substantially equivalent to that of the antenna device 1. In other respects, the present embodiment can achieve the same effects as those of the first embodiment.

(Embodiment 3)
An antenna device 1b according to Embodiment 3 of the present invention will be described with reference to FIGS. In FIG. 15, the illustration of the antenna case 2 and the outer pad 80 shown in FIG. 17 is omitted. In FIG. 18, the rear waterproof pad 50 is not shown.

As shown in FIG. 17, the antenna device 1b includes an antenna case 2, an outer pad 80, an antenna element 10, a substrate 7, a holder 30, a base (rear base) 3, a rear waterproof pad 50, a rear bolt 53, a front base cover 63, A movable base 60, a front fixed base 61, a front waterproof pad 62, a front bolt 51, and a nut 52 are included.

The antenna case 2 is, for example, a radio wave-transmitting resin molded body and covers the antenna element 10. The outer pad 80 is made of an elastic body such as rubber and fills a gap between the antenna case 2 and the vehicle roof 200 to which the antenna device 1b is attached. The antenna element 10 has the same function as the antenna element 10 of the first embodiment. The holder 30 is a member that holds the antenna element 10 and is, for example, a resin molded body. The base 3 is provided below the holder 30 and holds the holder 30 and the substrate 7. A cable 7 b extends from the substrate 7.

The rear waterproof pad 50 is made of an elastic body such as rubber, and is provided below the base 3 to seal between the antenna case 2 and the vehicle roof 200 in a watertight manner. The rear bolt 53 is screwed into the base 3 from below via a washer 54 and a holder 55 to fix the antenna device 1b to the vehicle roof 200. The six screws 101 pass through the rear waterproof pad 50, the base 3, and the holder 30, and are screwed to the six bosses 35 (FIG. 23) for screwing the antenna case 2, so that the holder 30, the base 3, and The rear waterproof pad 50 is fixed to the antenna case 2.

The front base cover 63 covers the upper part of the movable base 60 and the front fixed base 61. The movable base 60 is provided on the front fixed base 61. The front waterproof pad 62 is made of an elastic body such as rubber, and is provided below the front fixed base 61 to seal the space between the antenna case 2 and the vehicle roof 200 in a watertight manner. The front bolt 51 extends downward through the movable base 60, the front fixed base 61, the front waterproof pad 62, and the vehicle roof 200 (FIG. 22), and is screwed to the nut 52 below the vehicle roof 200, thereby providing an antenna device. 1b is fixed to the vehicle roof 200. The four screws 102 pass through the front waterproof pad 62, the front fixing base 61, and the front base cover 63, and are screwed to the four bosses 36 (FIG. 23) for screwing the antenna case 2, so that the front waterproof pad 62, the front fixing base 61 and the front base cover 63 are fixed to the antenna case 2.

In the present embodiment, as shown in FIGS. 15 and 17, two claw portions 25 are provided upward on each of the third side portion 17 and the fourth side portion 18 of the antenna element 10. The holder 30 for supporting is provided with a receiving portion 31 that holds the claw portion 25 downward. Since the nail | claw part 25 is suppressed by the receiving part 31, the upward vibration of the antenna element 10 is suppressed, and it can suppress that the antenna element 10 contacts the antenna case 2 and an abnormal noise generate | occur | produces.

As shown in FIG. 18, an elastic body 32 such as rubber is provided between the holder 30 and the antenna element 10, thereby suppressing downward vibration of the antenna element 10, so that the antenna element 10 is held in the holder 30. It is possible to suppress the generation of abnormal noise by touching. The elastic body 32 is provided at a total of two locations, one at least on the diagonal line of the holder 30. The elastic body 32 is provided on the opposite side of the first connection portion 11 and the second connection portion 12 in the left-right direction. Since the antenna element 10 is lifted upward with respect to the holder 30 by the elastic body 32, even if the height of the antenna element 10 varies, the claw portion 25 comes into contact with the receiving portion 31, and the antenna The play of the element 10 is prevented.

As shown in FIG. 19, the holder 30 is placed on the base 3. The rear waterproof pad 50 is provided below the base 3 and goes around the upper surface of the outer periphery of the holder 30. The waterproof rib 26, which is a protrusion extending downward from the antenna case 2, suppresses the wraparound portion from above. Since the holder 30 is mounted on the base 3 in the antenna device 1b, the vertical length of the waterproof rib 26 can be shortened compared to when the holder 30 is not mounted, and the possibility of molding failure of the waterproof rib 26 is reduced. be able to.

As shown in FIGS. 20 and 21, the

contact portions

60a and 61a, which are the places where the movable base 60 and the front fixed base 61 are in contact with each other, are curved in a cylindrical surface parallel to each other. The contact portion 60a is curved so as to protrude downward, and the contact portion 61a is recessed downward and curved. As shown in FIG. 22, when the front bolt 51 is tightened with a nut 52 when the vehicle roof 200 is curved, the movable base 60 is tilted and the antenna device 1 b is fixed to the vehicle roof 200. Thereby, even if the vehicle roof 200 is curved, the antenna device 1b can be fixed without opening a gap between the antenna device 1b and the vehicle roof 200.

The antenna device 1b is attached to the vehicle roof 200 at two front and rear positions by a front bolt 51 and a rear bolt 53. Thereby, it can fix to the vehicle roof 200 more firmly than when attaching to the vehicle roof 200 only by one place. Further, the fixing portion (front bolt 51, rear bolt 53) may be damaged when an external force is applied to the antenna device 1b attached to the vehicle roof 200, rather than being attached to the vehicle roof 200 at only one location. Can be lowered. Furthermore, since it is attached to the vehicle roof 200 at two places in the front and rear, it can be stably fixed to the vehicle roof 200 even if the length in the front-rear direction of the antenna device 1b is longer than when it is attached at one place. Can do.

When attaching the antenna device 1b to the vehicle roof 200, the front bolt 51 is tightened with the nut 52 after the rear bolt 53 is tightened. Thereby, even if there is a gap between the antenna device 1b and the vehicle roof 200, the movable base 60 follows the vehicle roof 200, so that the antenna device 1b is fixed without opening a gap with the vehicle roof 200. be able to. That is, even if a gap is generated between the antenna device 1b and the vehicle roof 200 when the rear bolt 53 is tightened, the movable base 60 follows the vehicle roof 200 to reduce the gap when the nut 52 is tightened with the front bolt 51. can do.

As shown in FIGS. 23 to 27, the outer pad 80 is attached to the antenna case 2 by the plate-like ribs 29 and the claw-like ribs 28 that protrude downward from the antenna case 2. The antenna case 2 is provided with ten plate-like ribs 29 and six claw-like ribs 28. The plate-like ribs 29 are press-fitted into the through holes 81 of the outer pad 80 with plate-like protrusions. The claw-shaped rib 28 has an inward projection and is inserted into the through hole 82 of the outer pad 80. As a result, the outer pad 80 is firmly attached to the antenna case 2, and the outer pad 80 is unlikely to be detached from the antenna case 2 even when an operator touches the outer pad 80 when attaching the antenna device 1 b to the vehicle roof 200.

The substrate 7 is provided with a terminal portion 7a composed of a pair of leaf springs, and the first connecting portion 11 is provided with a protruding portion 11a. The antenna element 10 is fixed to the holder 30 and the substrate 7 at three locations, that is, an attachment screw 74, an attachment screw 75, and a pinching of the protruding portion 11a by the terminal portion 7a. If the antenna element 10 is all tightened with mounting screws due to manufacturing variations of the antenna element 10 or the like, the height of the antenna element 10 may vary or the antenna element 10 may be distorted. Such variations and distortions can be suppressed by inserting the protruding portion 11a into the terminal portion 7a and fixing the antenna element 10 to the holder 30 and the substrate 7.

As shown in FIG. 23, the

bosses

35 and 36 for screwing the antenna case 2 are provided with the thinned

portions

35a and 36a at the depth portions where the screws 101 and 102 (FIG. 17) do not reach (the thinned portions). Is given). Since the resin used for the antenna case 2 shrinks during cooling, the antenna case 2 shrinks more as the thickness increases. For this reason, the outer surface of the location where the boss 35 of the antenna case 2 is provided may be recessed. If the

bosses

35 and 36 of the antenna case 2 are thinned, the occurrence of such a dent on the outer surface of the antenna case 2 can be suppressed.

The tip of the front bolt 51 is preferably spherical (curved surface). If the front bolt 51 has an angular tip, the front bolt 51 may be damaged around the hole when the front bolt 51 is inserted into the hole provided in the vehicle roof 200. If the periphery of the hole is damaged, the paint on the vehicle roof 200 may be peeled off and rusted. If the front bolt 51 has a spherical tip, the possibility of damaging the vehicle roof 200 at the tip of the front bolt 51 can be reduced.

As shown in FIG. 29, the outer pad 80 may have a folded portion 85 that extends horizontally inward in the lowermost portion (contact portion with the vehicle roof 200). If there is a gap between the antenna device 1b and the vehicle roof 200 when the antenna device 1b is attached to the vehicle roof 200, the compression reaction force of the outer pad 80 may affect the attachment posture of the antenna device 1b. In the outer pad 80 shown in FIG. 29, there is a gap above the folded-back portion 85, and the compression reaction force of the outer pad 80 is reduced by this gap compared to the case without the folded-back portion 85 (FIG. 28). For this reason, even if there is a gap between the antenna device 1b and the vehicle roof 200 when the antenna device 1b is attached to the vehicle roof 200, the compression reaction force of the outer pad 80 hardly affects the attachment posture of the antenna device 1b.

When the antenna device 1b is attached to the vehicle roof 200 or during high-pressure car washing by a car wash machine, the lowermost side portion 87 (see FIG. 28) of the outer pad 80 may be caught inside. In such a case, the waterproof performance of the antenna device 1b is lowered. On the other hand, as shown in FIG. 29, when the outer pad 80 has the turn-up portion 85, the area in contact with the vehicle roof 200 increases, so when attaching the antenna device 1b to the vehicle or during high-pressure car washing by the car wash machine, It is possible to reduce the possibility that the side portion of the outer pad 80 is wound inside and the waterproof performance is lowered.

The present invention has been described above by taking the embodiment as an example. However, it is understood by those skilled in the art that various modifications can be made to each component and each processing process of the embodiment within the scope of the claims. By the way. Hereinafter, modifications will be described.

The third connection unit 13 may be omitted. In this case, although VSWR deteriorates, the effect of enhancing the directivity in the direction parallel to the ground conductor plate 5 can be obtained.

1 antenna device, 1a antenna device, 1b antenna device, 2 antenna case, 3 base (rear base), 4 housing, 5 ground conductor plate, 5a opening, 7 substrate, 7a terminal, 7b cable, 10 antenna element, 11 1st connection part, 11a protrusion part, 12 2nd connection part, 12a 2nd connection part, 13 3rd connection part, 15 1st edge part, 16 2nd edge part, 17 3rd edge part, 18 4th edge Part, 19 bridging part, 21 4th connecting part, 23 top face part, 25 claw part, 26 waterproof rib, 28 claw shaped rib, 29 plate shaped rib, 30 holder, 31 receiving part, 32 elastic body, 35 boss, 35a meat Unplugged part, 36 boss, 36a meat cutout part, 50 rear waterproof pad, 51 front bolt, 52 nut, 53 rear bolt, 54 washer, 5 holder, 60 movable base, 60a contact part, 61 front fixed base, 61a contact part, 62 front waterproof pad, 63 front base cover, 74 mounting screw, 75 mounting screw, 80 outer pad, 81 through hole, 82 through hole, 85 folding part, 87 side part, 101 screw, 102 screw, 200 vehicle roof, 801 antenna device, 810 antenna element, 812 second connection part

Claims

A ground conductor plate and an antenna element;
The antenna element includes a circular portion that goes around substantially parallel to the ground conductor plate, a first connection portion that extends from the circular portion, and has an end portion as a feeding point, the circular portion, and the ground conductor plate. A second connecting portion that electrically connects the two, and a bridging portion that divides the internal region of the circulating portion,
The antenna device, wherein both ends of the bridging portion are electrically connected to the circulating portion at positions separated from the first and second connection portions by a predetermined distance or more.
The antenna device according to claim 1, wherein the predetermined distance is 1/8 or more of a circulation length of the circulation section.
The circumferential portion has first to fourth sides and circulates in a rectangular shape, and the first and second connecting portions extend from the first and second sides facing each other of the circumferential portion, respectively. The antenna device according to claim 1, wherein the bridging portion is provided so as to pass the third and fourth sides to each other.
The antenna device according to claim 3, wherein the bridging portion passes between the middle points of the third and fourth side portions.
The antenna device according to any one of claims 1 to 4, wherein the circulating portion is along an outer edge of the ground conductor plate when viewed from a direction perpendicular to the ground conductor plate.
6. The antenna element according to claim 1, wherein the antenna element includes a third connection portion that electrically connects the bridge portion and the ground conductor plate to each other, and an end portion of the third connection portion is grounded. The antenna apparatus as described in any one.
The antenna device according to any one of claims 1 to 6, wherein the second connection portion has a plate shape.
The antenna device according to any one of claims 1 to 7, wherein the first and second connection portions respectively extend from a pair of diagonal portions of the circulation portion.
The antenna device according to any one of claims 1 to 8, wherein the antenna element is for LTE.