JP2015053534A - Antenna device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antenna device capable of maintaining antenna performance, and avoiding a large size of an overall communication apparatus including the antenna device, when the antenna device is attached to a communication apparatus inside a dashboard of a vehicle.SOLUTION: An antenna device includes: a first metal plate 1; a second metal plate 2 having a first plane 2a set parallel to the first metal plate 1; and a power feeding element 1. A slot antenna 10 is formed of: the first metal plate 1; the second metal plate 2; and the feed element 3. The second metal plate 2 has two second planes 2b formed perpendicular to the first plane 2a. A gap between the two second planes 2b is set longer than a gap between one plane of the first metal plate 1 and the first plane 2a. Further, an area of the first metal plane 1 is greater than an area of the first plane 2a. An attachment section 1a for attaching to a communication apparatus is provided in a region of the first metal plate 1 where the slot antenna 10 is not formed.

Description

  The present invention relates to an antenna device, and more particularly to an antenna device that can be attached to a communication device in a dashboard of a vehicle.

  In recent years, with the development of wireless communication, a wireless interface in a vehicle has attracted attention. For example, when a mobile phone or smartphone is brought into a car, hands-free calling with a hands-free kit is performed, so a conventional short-range wireless communication device (for example, Bluetooth (registered trademark)) is used to connect a wired connection. To do it. Moreover, not only a mobile phone and a smart phone but a portable information terminal is also provided with a wireless interface, and for example, it is considered to transmit / receive data to / from a car navigation device of a vehicle and share it. For this reason, wireless LANs have been used even in vehicles. Accordingly, a plurality of communication devices have been used in the vehicle.

  For such a wireless interface, an antenna device for performing wireless communication is required. In this case, it is assumed that the antenna device is installed in a vehicle dashboard as a position where the antenna device is installed in the vehicle. The An antenna device using a slot antenna is conceivable as an antenna device that can be attached to a communication device in a dashboard of a vehicle. When there are a plurality of communication devices, an antenna device having a plurality of slot antennas is required. A slot antenna having a three-dimensional structure by increasing the volume of an antenna element in order to improve antenna performance is known.

  As a conventional slot antenna, Patent Document 1 discloses a slot antenna 900. FIG. 12 shows a slot antenna 900.

  A slot antenna 900 according to the prior art includes a conductive ground plane 902 having a slot portion 904 formed therein. The slot portion 904 has a length L that is substantially equal to a half wavelength of the radio wave. The slot portion 904 has a width w shorter than the length L, and further includes a vertical axis 906, a first vertical edge 908, and a second vertical edge 910. The width w preferably satisfies the relationship w << λ (λ is the wavelength of the signal to be handled).

  In addition, a conductive box structure 912 that is conductively fixed to the conductive ground plane 902 and configured so that the slot antenna 900 radiates only from one side of the conductive ground plane 902 is included. As shown in FIG. 12, the slot antenna 900 radiates outward from the conductive ground plane 902, and radiation in the opposite direction is blocked by the conductive box structure 912. Thus, the conductive box structure 912 can be configured to function as a waveguide that achieves the desired single side emission.

Japanese Patent Laid-Open No. 2002-084128

  By the way, when it is going to attach an antenna apparatus to the communication apparatus in the dashboard of a vehicle, the metal frame used as the housing | casing of a communication apparatus exists in the dashboard in which the communication apparatus is accommodated. Since the metal frame functions to block radio waves, the antenna device cannot be stored in the dashboard, and the antenna device has to be installed in a space in front of the communication device. Therefore, it has been necessary to attach to a display part of a communication device, for example, a thin bezel part (frame part) surrounding the monitor display part.

  However, in the slot antenna 900, the slot portion 904 is formed inside the conductive ground plane 902. For this reason, when the slot antenna 900 is to be attached to a communication device in the dashboard of the vehicle, it is very difficult to attach the slot antenna 900 to the thin bezel portion of the display portion of the communication device due to the large area of the conductive ground plane 902. It was.

  The present invention has been made in view of the actual situation of the prior art, and the purpose thereof is to maintain the antenna performance when the antenna device is attached to the communication device in the dashboard of the vehicle. An object of the present invention is to provide an antenna device capable of avoiding an increase in size of the entire communication device including the antenna device itself.

  In order to solve this problem, an antenna device of the present invention includes a first metal plate having a rectangular shape, a first plane set in parallel to the first metal plate, and the first metal plate. A second metal plate connected to one surface, and a power feeding element provided between the first metal plate and the first plane, and a part of the first metal plate and the A slot antenna is formed by a second metal plate and the power feeding element, and the antenna device can be attached to a communication device, wherein the first metal plate has a rectangular shape on the first plane, Each of the first planes has a second plane that is bent from two sides on the short side of the first plane and formed perpendicular to the first plane. The distance between the two second planes is connected to one surface of the first metal plate It is set to be longer than the distance between one surface and the first plane, and the area of the first metal plate is larger than the area of the first plane, on the first metal plate. A mounting portion for mounting to the communication device is provided in a region where the slot antenna is not formed.

  In the antenna device configured as described above, when the antenna device is to be attached to the communication device in the dashboard of the vehicle, the attachment portion is provided in the region where the slot antenna is not formed on the first metal plate. Therefore, the slot antenna can be installed on the front side of the communication device. As a result, since the antenna device can be installed outside the metal frame in the communication device, the antenna performance can be maintained. Further, the distance between the two second planes is set to be longer than the distance between one surface of the first metal plate and the first plane, that is, the antenna device is set to be horizontally long. Therefore, the antenna device can be accommodated within the range of the bezel portion by attaching the longitudinal direction of the antenna device to the longitudinal direction of the bezel portion on the near side of the communication device. As a result, it is possible to avoid an increase in the size of the entire communication device including the antenna device.

  In the above configuration, the antenna device of the present invention is characterized in that a screw hole is provided in the mounting portion.

  The antenna device configured as described above is provided with a screwing hole in a mounting portion in a region where a slot antenna is not formed, so that the antenna device can be easily connected to a communication device without affecting the antenna performance. Can be attached to.

  In the above configuration, the antenna device of the present invention has two slot antennas, and the distance between the two second planes in each of the slot antennas is ½ of the wavelength of the high-frequency signal to be handled. It has the feature of length.

  In the antenna device configured as described above, each slot antenna is an antenna in which the length in the longitudinal direction of the slot antenna is ½ of the signal wavelength. It is not affected by the frame. Therefore, the isolation between the two slot antennas can be increased, and the antenna performance can be maintained.

  In the above configuration, the antenna device of the present invention is characterized in that the first metal plate in each of the slot antennas is configured by a single metal plate.

  In the antenna device configured as described above, since the first metal plate constituting each of the two slot antennas is formed by a single metal plate, the relative position of the two slot antennas does not change, so that the two slot antennas are not changed. The positional accuracy can be increased. Therefore, the performance of each slot antenna in the antenna device can be improved. Moreover, since it forms using one metal plate, it can make manufacture easy.

  In the above configuration, the antenna device of the present invention has two slot antennas arranged close to each other, and the two slot antennas are arranged side by side in the longitudinal direction and symmetrical to each other. It has the feature that it is arranged.

  In the antenna device configured in this way, two slot antennas are arranged side by side in the longitudinal direction. Therefore, when the antenna device is to be attached to a communication device in the dashboard of the vehicle, The metal plate can be attached so that the longitudinal direction of the metal plate matches the longitudinal direction of the front surface of the communication device. Therefore, it is possible to avoid an increase in the size of the communication device. In addition, since the two antenna devices are symmetrically arranged, when two antenna devices are used at the same frequency, if one antenna device is optimized, the other antenna is also optimized. It can be done easily.

  In the above configuration, the antenna device of the present invention is characterized in that one ends of the two slot antennas are arranged close to each other, and the two slot antennas are arranged at right angles to each other.

  In the antenna device configured as described above, since the two slot antennas are arranged at right angles to each other, the polarizations of the two slot antennas can be orthogonal to each other. Therefore, the isolation between the two slot antennas can be increased.

  In the above configuration, the antenna device of the present invention is characterized in that each of the feeding elements of the two slot antennas is provided at a position closer to the other slot antenna than the center position of each slot antenna. Have

  Since the antenna device configured in this way can provide two feeding elements close to each other, wiring becomes easy.

  Further, in the above configuration, the antenna device according to the present invention has a length in the longitudinal direction of the metal plate that is longer than a length in which the two slot antennas are connected in the longitudinal direction, and both end portions in the longitudinal direction of the metal plate. And a screw hole is provided in the protrusion, and the screw hole is also provided between the slot antennas at a substantially central portion of the metal plate. Has characteristics.

  The antenna device configured in this manner has protrusions at both ends in the longitudinal direction of the metal plate, and the screw holes are provided in the protrusions. When trying to attach to the internal communication device, it is possible to easily attach the metal plate so that the longitudinal direction of the metal plate matches the longitudinal direction of the bezel portion on the front surface of the communication device. At the same time, since the antenna device is attached to the lower side of the bezel portion, the amount of protrusion from the front surface of the communication device to the front side can be reduced. In addition, since the screw holes are provided between the slot antennas at the substantially central portion of the metal plate, the antenna device can be securely attached to the communication device.

  Further, in the above configuration, the antenna device according to the present invention has an extension portion formed in the metal plate extending in a short direction of the metal plate, and a screw fixing hole is provided in the extension portion. It has the feature of being.

  In the antenna device configured in this way, the screwing holes are provided in the extending part extending in the short direction of the metal plate, so that the positions of the screwing holes can be efficiently arranged. Therefore, the antenna device can be securely attached to the communication device.

  The antenna device of the present invention is provided with an attachment portion in a region where the slot antenna is not formed on the first metal plate when the antenna device is to be attached to a communication device in the dashboard of the vehicle. A slot antenna can be installed on the front side of the communication device. As a result, since the antenna device can be installed outside the metal frame in the communication device, the antenna performance can be maintained. Further, the distance between the two second planes is set to be longer than the distance between one surface of the first metal plate and the first plane, that is, the antenna device is set to be horizontally long. Therefore, the antenna device can be accommodated within the range of the bezel portion by attaching the longitudinal direction of the antenna device to the longitudinal direction of the bezel portion on the near side of the communication device. As a result, it is possible to avoid an increase in the size of the entire communication device including the antenna device.

It is a perspective view which shows the structure of the antenna apparatus which concerns on 1st Embodiment of this invention. It is a perspective view which shows the relationship between the antenna device which concerns on 1st Embodiment of this invention, and communication equipment. It is a perspective view which shows the structure of the antenna device which concerns on 2nd Embodiment of this invention. It is the top view and side view of an antenna device which concern on 2nd Embodiment of this invention. It is a perspective view which shows the relationship between the antenna device which concerns on 2nd Embodiment of this invention, and a communication apparatus. It is a perspective view which shows the relationship between the antenna device which concerns on 2nd Embodiment of this invention, and a communication apparatus. It is a graph showing the frequency characteristic of the antenna device which concerns on 2nd Embodiment of this invention. It is a perspective view which shows the structure of the antenna device which concerns on 3rd Embodiment of this invention. It is a perspective view which shows the relationship between the antenna device which concerns on 3rd Embodiment of this invention, and a communication apparatus. It is a perspective view which shows the structure of the antenna device which concerns on 4th Embodiment of this invention. It is a perspective view which shows the relationship between the antenna device which concerns on 4th Embodiment of this invention, and a communication apparatus. It is a perspective view which shows the structure of the slot antenna which concerns on a prior art example.

  Hereinafter, an antenna device of the present invention will be described with reference to the drawings. In the description of each drawing, the X1 side may be expressed as the right side, the X2 side as the left side, the Y1 side as the back side, the Y2 side as the near side, the Z1 side as the upper side, and the Z2 side as the lower side.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2.

  FIG. 1 is a perspective view showing the configuration of the antenna device 100 according to the first embodiment of the present invention, and FIG. 2 is a perspective view showing the relationship between the antenna device 100 and the communication device 50. In FIG. 2, the communication device main body on the Y1 direction side is omitted as the communication device 50.

  As shown in FIG. 1, the antenna device 100 includes a first metal plate 1, a second metal plate 2, a feed element 3, a transmission cable 6, and a support member 7. The first metal plate 1 has a rectangular shape in which the X1-X2 direction (left-right direction) is the longitudinal direction and the Y1-Y2 direction (front-back direction) is the short direction. The second metal plate 2 is bent from two sides on the short side of the first plane 2a and the first plane 2a having a rectangular shape set parallel to the first metal plate 1, and the first plane 2a. And two second planes 2b formed perpendicularly to each other. The side of the end of each second plane 2b is connected to one surface (the surface on the Z1 side) of the first metal plate 1. The second metal plate 2 is attached close to the Y2 direction side (front side) of the first metal plate 1. The second metal plate 2 is supported and fixed by a support member 7 placed on one surface (Z1 side surface) of the first metal plate 1. The support member 7 is fixed in contact with the upper surface of the first metal plate 1 and the lower surface of the first plane 2 a of the second metal plate 2. The support member 7 is made of synthetic resin, and contributes to reducing the size of the antenna device 100 by its dielectric effect in addition to the function of supporting the second metal plate 2.

  In the antenna device 100, a part of the first metal plate 1, the first plane 2a of the second metal plate 2, and the two second planes 2b of the second metal plate 2 are in the Y1-Y2 direction (front-rear direction). A slot portion 4 having an opening is formed. The interval between the two second planes 2 b is set longer than the interval between one surface of the first metal plate 1 and the first plane 2 a of the second metal plate 2. Therefore, the slot portion 4 has a rectangular parallelepiped shape in which the X1-X2 direction (left-right direction) is the longitudinal direction. In addition, in the Z1-Z2 direction (vertical direction) of the slot portion 4, a power feeding element 3 is provided between the first metal plate 1 and the first plane 2a of the second metal plate 2, and power feeding is performed. Power is supplied to the slot portion 4 by the element 3. In the antenna device 100, the slot antenna 10 is formed by the slot portion 4 and the feed element 3. As shown in FIG. 1, a transmission cable 6 is connected to the feed element 3. The transmission cable 6 is connected to the communication device 50 and transmits signals.

  As shown in FIG. 1, the area of the first metal plate 1 is set larger than the area of the first plane 2 a of the second metal plate 2, and the slot antenna 10 is not formed on the first metal plate 1. A mounting portion 1a having a plurality of screw holes 1b is provided in the region. As shown in FIG. 2A, the antenna device 100 can be attached to the communication device 50 by the attaching portion 1a.

  As shown in FIG. 2A, the antenna device 100 according to the first embodiment of the present invention is attached to the front side of a communication device 50 used for a car navigation device of a vehicle, for example. A monitor display unit 55 is attached to the front side of the communication device 50, and the periphery of the monitor display unit 55 is a bezel unit 53. The antenna device 100 is attached to the lower bezel portion 53a corresponding to the lower side (Z2 side) of the monitor display portion 55. A bracket 52 is attached to the lower bezel portion 53a, and the bracket 52 is provided with a plurality of screw holes 52a. The monitor display unit 55 may be an operation unit for operating the communication device 50.

  As shown in FIG. 2A, the antenna device 100 is attached to the bracket 52 by a plurality of attachment screws 8. The antenna device 100 is mounted such that the mounting portion 1a on one surface (the surface on the Z1 side) of the first metal plate 1 contacts the lower surface (the surface on the Z2 side) of the bracket 52. A state where the antenna device 100 is attached to the communication device 50 is shown in FIG.

  Generally, when an antenna device is attached to a communication device in a dashboard of a vehicle, a metal frame that functions to block radio waves is present inside the communication device, so the antenna device is located in a space in front of the communication device. Need to be installed in As shown in FIG. 1 and FIG. 2A, the antenna device 100 is provided with a mounting portion 1a in a region where the slot antenna 10 is not formed on the first metal plate 1, so that the slot antenna 10 communicates with the antenna device 100. It can be installed on the front side of the device 50. As a result, antenna performance can be maintained. At the same time, the distance between the two second planes 2b is longer than the distance between one surface of the first metal plate 1 and the first plane 2a of the second metal plate 2, that is, the antenna device 100 is It is set to be horizontally long. Therefore, by attaching the longitudinal direction of the antenna device 100 to the longitudinal direction of the bezel portion 53 on the front side of the communication device 50, the antenna device 100 can be accommodated within the range of the bezel portion 53. As a result, an increase in the size of the entire communication device including the antenna device 100 can be avoided.

[Second Embodiment]
Next, the configuration of the antenna device 200 according to the second embodiment of the present invention will be described with reference to FIGS.

  FIG. 3 is a perspective view showing a configuration of an antenna device 200 according to the second embodiment of the present invention, and FIG. 4 is a plan view (a) and a side view (b) of the antenna device 200. 5 and 6 are perspective views showing the relationship between the antenna device 200 and the communication device 50. FIG. FIG. 7 is a graph showing frequency characteristics of the antenna device 200 according to the second embodiment of the present invention. In FIG. 5, the communication device main body on the Y1 direction side is omitted as the communication device 50.

  As shown in FIG. 3, the antenna device 200 includes one metal plate 11, two second metal plates 12, two power feeding elements 13, two transmission cables 16, and two support members 17. Has been. Each slot antenna 20 is constituted by a slot portion 14 constituted by a part of the metal plate 11 and the second metal plate 12 and the feed element 13. In the antenna device 200, the first metal plate in each slot antenna 20 is constituted by one metal plate 11. Further, each slot antenna 20 in the antenna device 200 is set so as to handle the same high-frequency signal frequency.

  Since the configuration of each slot antenna 20 in the antenna device 200 is the same as the configuration of the slot antenna 10 in the antenna device 100 described above, detailed description of each slot antenna 20 is omitted.

  In the antenna device 200, as shown in FIG. 3 and FIG. 4B, two slot antennas 20 are formed on a common metal plate 11. As shown in FIG. 4A, the two slot antennas 20 are provided close to the front side (Y2 side) of the metal plate 11. One end of each of the two slot antennas 20 is arranged close to each other, and the two slot antennas 20 are arranged side by side in the longitudinal direction (X1-X2 direction) and are arranged symmetrically with each other. Further, the feeding elements 13 of the two slot antennas 20 are provided at positions closer to the other slot antenna 20 than the center position of the respective slot antennas 20. The two transmission cables 16 are grouped together on the route and connected to the communication device 50.

  As shown to Fig.4 (a), the extension part 11c extended to the back | inner side (Y1 side) of the transversal direction (Y1-Y2 direction) of the metal plate 11 is formed in the metal plate 11. The mounting portion 11a is configured. The extension portion 11c is provided with a plurality of screw holes 11b.

  Similar to the antenna device 100, the antenna device 200 according to the second embodiment of the present invention is attached to a communication device 50 used in, for example, a car navigation device for a vehicle. As shown in FIG. 5A, a monitor display unit 55 is attached, and the periphery of the monitor display unit 55 is a bezel unit 53. The antenna device 200 is attached to the lower bezel portion 53a corresponding to the lower side (Z2 side) of the monitor display portion 55. A bracket 62 is attached to the lower bezel portion 53a, and the bracket 62 is provided with a plurality of screw holes 62a.

  As shown in FIG. 5A, the antenna device 200 is attached to the bracket 62 by a plurality of attachment screws 8. The antenna device 200 is attached such that the extending portion 11c on one surface (the surface on the Z1 side) of the metal plate 11 abuts on the lower surface (the surface on the Z2 side) of the bracket 62. FIG. 5B shows a state where the antenna device 200 is attached to the communication device 50. The antenna device 200 is mounted so as to fit within the width in the left-right direction of the bezel portion 53 around the monitor display portion 55.

  Thus, since the antenna device 200 is formed of the metal plate 11 that is a part of each slot antenna 20 by a single plate, the relative position of the two slot antennas 20 does not change, and thus the positional accuracy of the two slot antennas 20 Can be high. Therefore, the antenna performance of the antenna device 200 can be improved. Moreover, since it forms using the metal plate 11 of 1 sheet, it can make it easy to manufacture.

  Since the two slot antennas 20 are arranged side by side in the longitudinal direction, when the antenna device 200 is to be attached to the communication device 50 in the dashboard of the vehicle, the length of the single metal plate 11 is increased. The direction can be attached in accordance with the left-right direction of the front surface of the communication device 50. Therefore, it is possible to avoid an increase in the size of the communication device 50. Further, since the two slot antennas 20 are arranged symmetrically with each other, when the two slot antennas 20 are used at the same frequency, if one slot antenna 20 is optimized, the other is also optimized. Can be easily performed.

  Further, since the feeding element 13 is provided at a position closer to the other slot portion than the center position of each slot antenna 20, wiring is facilitated.

  Moreover, since the screwing hole 11b is provided in the extending part 11c extended in the short direction of the metal plate 11, the position of the screwing hole 11b can be efficiently arranged. Therefore, 20200 can be reliably attached to the communication device 50.

  FIG. 6 shows a communication device 50 including the communication device main body 51. As shown in FIG. 6, the communication device main body 51 is surrounded by a metal frame 54. Since the metal frame 54 has a function of shielding high-frequency signals, the antenna device 200 cannot be installed in the metal frame 54. The metal frame 54 is also a ground conductor of a communication device circuit (not shown) in the communication device main body 51.

  The two slot antennas 20 in the antenna device 200 have the same frequency of the high frequency signal to be handled, and the length in the longitudinal direction is set to ½ the wavelength of the high frequency signal to be handled. In general, in the case of an antenna device in which the length of the antenna element is set to ½ the wavelength of the high-frequency signal handled, the ground conductor is not necessary. In other words, it is considered that an antenna device is formed by a single antenna element. On the other hand, in the case of an antenna device in which the length of the antenna element is set to ¼ of the wavelength of the high-frequency signal handled, a ground conductor is required in addition to the antenna element. In other words, it is considered that an antenna device is formed by two antenna elements and a ground conductor.

  If the length of the antenna element is set to ¼ of the wavelength of the high-frequency signal handled, and there is one antenna device, the metal frame 54 in the communication device 50 is used as a ground conductor for the antenna device. Can contribute to antenna performance. However, when the length of the antenna element is set to ¼ of the wavelength of the high-frequency signal to be handled and two antenna devices that handle the same frequency are installed close to each other, Mutual antenna currents flow into each other. As a result, since the two antenna elements interfere with each other through the metal frame 54, the coupling between the two antenna elements increases, and the isolation between them deteriorates.

  In the antenna device 200 according to the second embodiment of the present invention, the length in the longitudinal direction of the slot portion 14 in the two slot antennas 20 that are antenna elements is set to be ½ of the wavelength of the high-frequency signal to be handled. Yes. As described above, in general, in the case of an antenna device in which the length of the antenna element is set to ½ of the wavelength of the high-frequency signal handled, the antenna device is formed only by the antenna element. In other words, even if the metal frame 54 exists in the vicinity, the influence of the metal frame 54 on the antenna performance is small. Accordingly, the two antenna elements are hardly coupled to each other, and the isolation between the two antenna elements can be increased.

  FIG. 7 shows the frequency characteristics of the antenna device 200. The return loss indicating the impedance of each of the two slot antennas 20 in the antenna device 200 shows a good numerical value at the frequency (2.40 GHz to 2.48 GHz) of the high-frequency signal to be handled. Further, the isolation between the two slot antennas 20 shows −36 dB or less at the same high-frequency signal frequency (2.40 GHz to 2.48 GHz). In general, as the isolation between two antennas, it can be said that a good numerical value is shown if it is −30 dB or less. Therefore, the antenna device 200 shows good isolation.

[Third Embodiment]
Next, the configuration of the antenna device 300 according to the third embodiment of the present invention will be described with reference to FIGS.

  FIG. 8 is a perspective view illustrating a configuration of an antenna device 300 according to the third embodiment of the present invention, and FIG. 9 is a perspective view illustrating a relationship between the antenna device 300 and the communication device 50.

  As shown in FIG. 8, the antenna device 300 includes one metal plate 21, two second metal plates 22, two power feeding elements 23, and two transmission cables 26. In addition, the slot portion 24 constituted by the metal plate 21 and the second metal plate 22 and the feed element 23 constitute the slot antenna 30 respectively. In the antenna device 300, two slot antennas 30 are configured. In addition, the two slot antennas 30 in the antenna device 300 have the same frequency of the high-frequency signal to be handled, and the length in the longitudinal direction is set to ½ the wavelength of the high-frequency signal to be handled. Yes.

  The metal plate 21 has a rectangular shape in which the X1-X2 direction (left-right direction) is the longitudinal direction and the Y1-Y2 direction (front-back direction) is the short direction. In each slot antenna 30, the second metal plate 22 is bent from a rectangular first plane 22 a set parallel to the metal plate 21 and two short sides of the first plane 22 a. And two second planes 22b formed perpendicular to the first plane 22a. And the edge part of each 2nd plane 22b is connected to one surface (surface by the side of Z2) of the metal plate 21. As shown in FIG. Accordingly, each slot antenna 30 is configured on the lower side (Z2 side) of the metal plate 21, contrary to the case of the antenna device 200.

  Slot portions 24 having openings in the Y1-Y2 direction (front-rear direction) on the metal plate 21, the first plane 22a of the second metal plate 22, and the two second planes 22b of the second metal plate 22, respectively. Forming. The interval between the two second planes 22 b is set longer than the interval between one surface of the metal plate 21 and the first plane 22 a of the second metal plate 22. Therefore, the slot portion 24 has a rectangular parallelepiped shape in which the X1-X2 direction (left-right direction) is the longitudinal direction. In the Z1-Z2 direction (vertical direction) of the slot portion 24, a power feeding element 23 is provided between the metal plate 21 and the first flat surface 22a of the second metal plate 22. As shown in FIG. 8, a transmission cable 26 is connected to the feed element 23. The transmission cable 26 is connected to the communication device 50 and transmits signals.

  As shown in FIG. 8, the width of the metal plate 21 in the Y1-Y2 direction is substantially the same as the width of the second metal plate 22 in the Y1-Y2 direction. Further, the length of the metal plate 21 in the longitudinal direction (X1-X2 direction) is longer than the length obtained by connecting two slot antennas in the longitudinal direction (X1-X2 direction). Furthermore, the protrusion part 21c is formed in each both ends of the longitudinal direction of the metal plate 21, and the screwing hole 21b is provided in this protrusion part 21c, respectively. The screw holes 21 d are also provided between the slot antennas 30 at the substantially central portion of the metal plate 21.

  The antenna device 300 according to the third embodiment of the present invention is the lower bezel corresponding to the lower side (Z2 side) of the monitor display unit 55 as shown in FIG. It is attached to the part 53a. A bracket 72 is attached to the lower bezel portion 53a, and the bracket 72 is provided with a plurality of screw holes 72a.

  As shown in FIG. 9A, the antenna device 300 is attached to the bracket 72 with a plurality of attachment screws 8. The antenna device 300 is attached such that one surface (surface on the Z1 side) of the metal plate 21 directly contacts the lower surface (surface on the Z2 side) of the bracket 72. FIG. 9B shows a state where the antenna device 300 is attached to the communication device 50. The antenna device 300 is attached so as to fit within the width in the left-right direction of the bezel portion 53 around the monitor display portion 55. Moreover, since it is attached within the width of the surface of the bracket 72 in the front-rear direction (Y1-Y2 direction) and the antenna device 300 is configured on the lower side (Z2 side) of the bracket 72, it is more than the bracket 72. The antenna device 300 does not protrude to the front.

  As described above, when the antenna device 300 is attached to the communication device 50 in the dashboard of the vehicle, the antenna device 300 is attached so that the longitudinal direction of the metal plate is aligned with the left-right direction of the bezel portion 53 on the front surface of the communication device 50. The amount of protrusion from the front surface of the communication device 50 to the front side can be reduced. Since the screw holes 21d are also provided between the slot antennas 30 at the substantially central portion of the metal plate 21, the antenna device 300 can be securely attached to the communication device 50.

[Fourth Embodiment]
Next, the structure of the antenna device 400 which is 4th Embodiment of this invention is demonstrated using FIG.10 and FIG.11.

  FIG. 10 is a perspective view showing the configuration of the antenna device 400 according to the fourth embodiment of the present invention, and FIG. 11 is a perspective view showing the relationship between the antenna device 400 and the communication device 50.

  As shown in FIG. 10, the antenna device 400 includes one metal plate 31, two second metal plates 32, and two support members 37. Note that the power feeding element and the transmission cable are omitted because they are the same as those of the antenna device 200. In the antenna device 400, two slot antennas 40 are configured. In addition, the two slot antennas 40 in the antenna device 400 have the same frequency of the high-frequency signal to be handled, and the length in the longitudinal direction is set to ½ the wavelength of the high-frequency signal to be handled. Yes.

  Since the configuration of each slot antenna 40 in the antenna device 400 is the same as the configuration of each slot antenna 20 of the antenna device 200 described above, that is, the slot antenna 10 of the antenna device 100, detailed description thereof is omitted.

  In the antenna device 400, as shown in FIG. 10, two slot antennas 40 are formed on a common metal plate 31. The metal plate 31 is bent at a right angle. The two slot antennas 40 are arranged close to each other. However, since the metal plate 31 is bent at a right angle, the two slot antennas 40 are arranged at a right angle.

  The antenna device 400 according to the fourth embodiment of the present invention is attached to the communication device 50 similarly to the antenna device 200. As shown in FIG. 11, a monitor display unit 55 is attached to the communication device 50, and a bezel unit 53 surrounds the monitor display unit 55. The antenna device 400 is attached across the lower bezel part 53a corresponding to the lower side (Z2 side) of the monitor display part 55 and the left bezel part 53b corresponding to the left side (X2 side) of the monitor display part 55. A bracket (not shown) is attached to the lower bezel portion 53a and the left bezel portion 53b, and the antenna device 400 is attached to the bracket by a plurality of attachment screws (not shown) in the same manner as the antenna device 200. It is done.

  Since the antenna device 400 configured as described above has the two slot antennas 40 arranged at right angles to each other, the polarizations of the two slot antennas 40 can be orthogonalized. Therefore, the isolation between the two slot antennas 40 can be increased.

  As described above, the antenna device of the present invention has an attachment portion in a region where the slot antenna is not formed on the first metal plate when the antenna device is to be attached to a communication device in the dashboard of the vehicle. Since it is provided, the slot antenna can be installed on the near side of the communication device. As a result, since the antenna device can be installed outside the metal frame in the communication device, the antenna performance can be maintained. Further, the distance between the two second planes is set to be longer than the distance between one surface of the first metal plate and the first plane, that is, the antenna device is set to be horizontally long. Therefore, the antenna device can be accommodated within the range of the bezel portion by attaching the longitudinal direction of the antenna device to the longitudinal direction of the bezel portion on the near side of the communication device. As a result, it is possible to avoid an increase in the size of the entire communication device including the antenna device.

  The present invention is not limited to the description of the first to fourth embodiments described above, and can be appropriately modified and implemented in a mode in which the effect is exhibited. For example, the antenna device may be attached not to the lower bezel portion of the monitor display portion but to the upper, right, or left bezel portion.

DESCRIPTION OF SYMBOLS 1 1st metal plate 1a Attachment part 1b Screw hole 2 2nd metal plate 2a 1st plane 2b 2nd plane 3 Feeding element 4 Slot part 6 Transmission cable 7 Support member 8 Attachment screw 10 Slot antenna 11 Metal plate 11a Attachment part 11b Screw hole 11c Extension part 12 2nd metal plate 12a 1st plane 12b 2nd plane 13 Feeding element 14 Slot part 16 Transmission cable 17 Support member 20 Slot antenna 21 Metal plate 21a Mounting part 21b Screw hole 21c Projection Portion 21d Screw hole 22 Second metal plate 23 Feed element 24 Slot portion 26 Transmission cable 30 Slot antenna 31 Metal plate 31a Mounting portion 31b Screw hole 31c Extension portion 32 Second metal plate 34 Slot portion 37 Support member 50 Communication device 51 Communication device body 52 Bracket 52a Di locking hole 53 bezel part 54 the metal frame 55 monitor display unit 62 bracket 62a screwed hole 72 bracket 72a screwed hole 100 Antenna 200 Antenna 300 Antenna 400 Antenna device

Claims (9)

A first metal plate having a rectangular shape; a second metal plate having a first plane set parallel to the first metal plate and connected to one surface of the first metal plate; A feed element provided between the first metal plate and the first plane, and a slot antenna is formed by a part of the first metal plate, the second metal plate, and the feed element. An antenna device that can be attached to a communication device,
In the second metal plate, the first plane has a rectangular shape, and is bent from two sides on the short side of the first plane, and is formed perpendicular to the first plane. And the side of the end of each of the second planes is connected to one surface of the first metal plate,
The distance between the two second planes is set to be longer than the distance between one surface of the first metal plate and the first plane, and the area of the first metal plate is An antenna device characterized in that an attachment portion for attaching to the communication device is provided in a region that is larger than the area of the first plane and on which the slot antenna is not formed on the first metal plate.   The antenna device according to claim 1, wherein a screw hole is provided in the attachment portion.   2. The slot antenna according to claim 1, wherein two slot antennas are provided, and an interval between the two second planes in each of the slot antennas is ½ of a wavelength of a high-frequency signal to be handled. Antenna device. The antenna device according to claim 3, wherein the first metal plate in each of the slot antennas is constituted by a single metal plate. One end of each of the two slot antennas is disposed close to each other,
The antenna device according to claim 4, wherein the two slot antennas are arranged side by side in the longitudinal direction and are arranged symmetrically with respect to each other.   5. The antenna device according to claim 4, wherein one ends of the two slot antennas are arranged close to each other, and the two slot antennas are arranged at right angles to each other.   7. The feed element of each of the two slot antennas is provided at a position closer to the other slot antenna than a center position of each slot antenna. The antenna device described. The length in the longitudinal direction of the metal plate is longer than the length in which the two slot antennas are connected in the longitudinal direction, projecting portions are formed at both ends in the longitudinal direction of the metal plate, and the projecting portions are screwed. Each hole is provided,
8. The antenna device according to claim 4, wherein the screw holes are provided between the slot antennas at a substantially central portion of the metal plate. An extension part extending in the short direction of the metal plate is formed on the metal plate,
The antenna device according to any one of claims 4 to 7, wherein a screw hole is provided in the extension portion.