JP2017126837A - Composite antenna device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite antenna device that improves antenna performance and is capable of being downsized.SOLUTION: A composite antenna device is composed of a ground plate 10, a patch antenna 20, and an antenna element 30. The patch antenna 20 is arranged at a position on the ground plate 10, the position being closer to and in the vicinity of the center, and includes a patch element surface 21 on a surface facing the ground plate 10. The antenna element 30 includes: a power supply part 31 that extends from a plate surface of the ground plate 10 so as to stand up in the vertical direction; and a radiation part 32 that is bent from the apex of the power supply part 31 so as to be in parallel with the ground plate 10 and extends in a horizontal direction apart from the patch element surface 21 of the patch antenna 20 with a predetermined gap so as to be at least in an L-shaped around the patch element surface 21. The radiation part 32 is arranged so as to be approximately flush with the vertical height of the patch element surface 21 of the patch antenna 20.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a composite antenna device, and more particularly to a composite antenna device capable of receiving signals in a plurality of frequency bands such as a mobile phone and a GNSS (Global Navigation Satellite System).

  Recently, various antennas have been mounted on vehicles. For example, various communication such as radio, television, mobile phone, GNSS, ETC (Electronic Toll Collection System), VICS (registered trademark) (Vehicle Information and Communication System) is realized. The necessary antenna is mounted on the vehicle. A vehicle roof is the most preferable reception condition, but the aesthetics are impaired and the installation work is complicated. For this reason, the antenna is housed in a dashboard in the vehicle or attached to glass. Here, for example, a composite antenna device is also known in which an inverted F antenna for a mobile phone and a patch antenna for GPS are accommodated in one housing and arranged in a dashboard. For example, in Patent Document 1, a concave portion for shielding is formed in the central portion of a flat portion of an inverted F-type antenna having a rectangular flat portion, and approximately half of the height direction of the GPS antenna is formed in the concave portion for shielding. It is inserted.

  Japanese Patent Laid-Open No. 2004-228561 accommodates two inverted F antennas and GPS and ETC patch antennas in a single casing. In this case, a GPS antenna is arranged at the approximate center on the base plate, and an inverted F antenna for a mobile phone is arranged around the GPS antenna so as to surround the GPS antenna.

Japanese Patent Application Laid-Open No. 11-312920 JP 2010-081500 A

  For composite antenna devices such as Patent Document 1 and Patent Document 2, it has been desired to improve antenna performance such as further widening the bandwidth, improving directivity, and improving gain. In addition, further miniaturization has been desired.

  In view of such circumstances, the present invention intends to provide a composite antenna device that has improved antenna performance and can be miniaturized.

  In order to achieve the above-described object of the present invention, a composite antenna device according to the present invention includes a plate-shaped ground plate that is a finite ground plane, and a patch element on a surface that is disposed near the center of the ground plate and faces the ground plate. A patch antenna having a flat surface, a feed portion extending so as to rise in a vertical direction from the plate surface of the ground plate, and a patch element surface of the patch antenna that is bent so as to be parallel to the ground plate from the top of the feed portion. Antenna element having a radiating portion extending at least in an L shape around the patch element surface at a predetermined interval, the radiating portion being substantially flush with the vertical height of the patch element surface of the patch antenna. The antenna element is arranged so as to be.

  Here, the antenna element may have a plate shape and may be arranged so that the plate-like surface of the radiating portion faces the plate surface of the ground plate.

  In addition, the antenna element further extends from the L shape so that the radiating portion surrounds the patch element surface around the patch element surface at a predetermined interval in the horizontal direction from the patch element surface of the patch antenna, and extends to the U shape. It may be present.

  The antenna element is a two-wave compatible element, and the radiating portion extends further from the L shape around the patch element surface in a horizontal direction to the patch element surface of the patch antenna and extends in a U shape. The first radiating portion and the patch element surface of the patch antenna extending in a L-shape around the patch element surface at a predetermined interval in the horizontal direction from the top of the feeding portion in a direction different from the first radiating portion. The second radiating portion may be arranged so that the first radiating portion and the second radiating portion substantially surround the patch element surface of the patch antenna.

  In addition, the patch antenna may be disposed by being lifted from the plate surface of the ground plate using a conductor or an insulator spacer so that the patch element surface is substantially flush with the height of the radiation portion of the antenna element. .

  Further, when the spacer is a conductor, the conductor may be electrically connected to the ground plate.

  Furthermore, a cover for accommodating the antenna element and the patch antenna is provided, and the patch element surface of the patch antenna is lowered from the height of the radiating portion of the antenna element to the ground plate side so as not to contact the inner surface of the cover. It may be arranged.

  Further, the feeding portion of the antenna element may extend in a tapered shape from the radiating portion toward the plate surface of the ground plate.

  The composite antenna device of the present invention has the advantages that the antenna performance is improved and the size can be reduced.

FIG. 1 is a partial cross-sectional schematic side view for explaining a composite antenna device of the present invention. FIG. 2 is a schematic top view for explaining the composite antenna device of the present invention. FIG. 3 is a schematic top view for explaining another example of the antenna element of the composite antenna device of the present invention. FIG. 4 is a schematic diagram for explaining another example of the antenna element of the composite antenna device of the present invention. FIG. 5 is a schematic top view for explaining another example of the ground plate of the composite antenna device of the present invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described together with illustrated examples. FIG. 1 is a schematic side view for explaining a composite antenna device of the present invention. FIG. 2 is a schematic top view for explaining the composite antenna device of the present invention. In the figure, the same reference numerals as those in FIG. 1 denote the same parts. In FIG. 2, the L-shaped bracket 1 and the cover 2 are omitted. As shown in the figure, the composite antenna apparatus of the present invention capable of receiving signals in a plurality of frequency bands is mainly composed of a ground plate 10, a patch antenna 20, and an antenna element 30. These are fixed on, for example, an L-shaped bracket 1 and covered with a cover 2. The L-shaped bracket 1 is fixed to a fixing portion in a dashboard (not shown) by screwing or the like.

  The ground plate 10 is a plate-like finite ground plane. In the illustrated example, the ground plate 10 has a rectangular plate surface. The L-shaped bracket 1 and the ground plate 10 may be common. That is, the ground plate 10 may be bent into an L-shaped bracket and used as a bracket.

  The patch antenna 20 is disposed near the center on the ground plate 10. Specifically, the patch antenna 20 may be a dielectric patch antenna, for example. Here, the patch antenna 20 is arranged near the center on the ground plate 10 because the area necessary for the antenna element 30 (described later) to be arranged so as to surround the patch antenna 20 is located in the peripheral portion of the ground plate 10. This is so that it can be left. Therefore, the patch antenna 20 does not necessarily need to be arranged at the center of the ground plate 10. For example, when the ground plate 10 is sufficiently large, this means that the patch antenna 20 may be appropriately offset from the center. The patch antenna 20 has a patch element surface 21 on the surface facing the ground plate 10. The patch element surface 21 is a radiation electrode surface. In addition, the back surface side of the patch antenna 20 may have a ground electrode surface as appropriate. The patch antenna 20 may be a GNSS antenna, for example.

  The antenna element 30 includes a power feeding unit 31 and a radiation unit 32. Specifically, in the illustrated example, an inverted L-type antenna element is shown. The power feeding portion 31 extends so as to rise in the vertical direction from the plate surface of the ground plate 10. More specifically, the power supply unit 31 is supplied with power from an external device via a cable while being insulated from the ground plate 10. And the radiation | emission part 32 is bent so that it may become parallel to the ground board 10 from the top part of the electric power feeding part 31. FIG. Here, the radiating portion 32 is illustrated as extending in an L shape around the patch element surface 21 at a predetermined interval in the horizontal direction from the patch element surface 21 of the patch antenna 20. That is, the radiating portion 32 is arranged in an L shape on the peripheral portion of the ground plate 10 while avoiding the vicinity of the center of the ground plate 10.

  The radiating portion 32 is disposed so as to be substantially flush with the vertical height of the patch element surface 21 of the patch antenna 20. In FIG. 1, the patch antenna 20 is lifted from the plate surface of the ground plate 10 by using the spacer 25, so that the height of the radiating portion 32 and the patch element surface 21 is substantially flush with each other. Indicated. The height of the spacer 25 is determined so that the thickness of the dielectric of the patch antenna 20 is less than the length of the feeding portion 31 of the antenna element 30 so that the height of the patch element surface 21 and the radiating portion 32 is substantially flush with each other. You can adjust with. Here, the spacer 25 may be a conductor or an insulator. When the spacer 25 is an insulator, for example, when the patch antenna 20 is lifted to a height that is flush with the antenna element 30 on the ground electrode surface side that is the surface opposite to the patch element surface 21 of the patch antenna 20. A spacer 25 having a height corresponding to the lift amount of the patch antenna 20, that is, a height corresponding to the distance from the ground electrode surface of the patch antenna 20 to the ground plate 10 may be attached.

  Further, in the case where the spacer 25 is a conductor, it may be configured such that the conductor is electrically connected to the ground plate 10. Thereby, since the ground electrode of the patch antenna 20 is increased by the ground plate 10, the antenna performance of the patch antenna 20 is further improved. At this time, the ground electrode surface of the patch antenna 20 and the conductive spacer 25 may be electrically connected.

  In addition, the patch element surface 21 of the patch antenna 20 and the radiating portion 32 of the antenna element 30 are adjusted to be substantially flush with each other. At this time, the patch element surface 21 is adjusted from the height of the radiating portion 32. You may arrange | position to the ground board 10 side lowered to some extent. If the patch element surface 21 comes into contact with the inner surface of the cover 2, the gain of the patch antenna 20 may be reduced. Accordingly, the patch element surface 21 may be disposed so as to be lowered from the height of the radiating portion 32 of the antenna element 30 toward the ground plate 10 so as not to contact the inner surface of the cover 2.

  Here, for example, the antenna length of the antenna element 30 may be determined so that an 800 MHz band signal of a mobile phone can be received. The illustrated antenna element 30 is a plate-like one. Thereby, the radiation | emission part 32 can further be shortened. Further, the plate-like antenna element can be easily manufactured by, for example, pressing a sheet metal. The plate-like antenna element 30 is arranged so that the plate-like surface of the radiating portion 32 faces the plate surface of the ground plate 10. That is, the radiation part 32 and the ground plate 10 are arranged in parallel in the direction in which the plate surfaces face each other.

  In addition, although the antenna element 30 showed the plate-shaped thing, this invention is not limited to this, For example, the linear antenna element comprised by conducting wire may be sufficient. Furthermore, the antenna element 30 is not limited to an inverted L-type antenna element, and may be an inverted F-type antenna element.

  Next, another example of the antenna element of the composite antenna device of the present invention will be described with reference to FIG. FIG. 3 is a schematic top view for explaining another example of the antenna element of the composite antenna device of the present invention. In the figure, the same reference numerals as those in FIG. 2 denote the same parts. In FIG. 3, the L-shaped bracket 1 and the cover 2 are omitted. As shown in the figure, the antenna element 30 of this example has a radiating portion 32 that surrounds the patch element surface 21 around the patch element surface 21 with a predetermined distance in the horizontal direction from the patch element surface 21 of the patch antenna 20. It further extends from the L shape and extends in a U shape. That is, the radiating portion 32 of the antenna element 30 is arranged so that the three sides of the patch element surface 21 are surrounded.

  In the composite antenna apparatus of the present invention, even if the antenna elements are arranged in this way, the antenna performance of the patch antenna 20 is not affected. Further, since the electrical length of the antenna element 30 can be extended, the size can be further reduced.

  In the example of FIG. 3, the antenna element 30 is a plate-like element, but the present invention is not limited to this, and may be a linear antenna element constituted by, for example, a conducting wire. The antenna element 30 is not limited to an inverted L-type antenna element, and may be an inverted F-type antenna element.

  Furthermore, still another example of the antenna element of the composite antenna device of the present invention will be described with reference to FIG. FIG. 4 is a schematic diagram for explaining another example of the antenna element of the composite antenna device of the present invention, FIG. 4 (a) is a schematic top view, and FIG. 4 (b) is a schematic front view thereof. is there. In the figure, the same reference numerals as those in FIG. 2 denote the same parts. In FIG. 4, the L-shaped bracket 1 and the cover 2 are omitted. The antenna element 30 in this example is a two-wave compatible element. That is, in the example shown in FIG. 4, the composite antenna device including the patch antenna 20 is compatible with a total of three waves. In the illustrated example described above, an example of an inverted L-type antenna element is shown. However, in this example, an example of using an inverted F-type antenna element having a short-circuit portion 35 is shown.

  As shown in the figure, the antenna element 30 of this example has a radiating portion 32 including a first radiating portion 33 and a second radiating portion 34. For example, the antenna length and the like are determined so that the first radiating unit 33 can receive an 800 MHz band signal of a mobile phone, and the second radiating unit 34 can receive an 2 GHz band signal of the mobile phone. The length has been decided. And the 1st radiation | emission part 33 is further extended from the L-shape at the periphery of the patch element surface 21 at predetermined intervals in the horizontal direction with the patch element surface 21 of the patch antenna 20, and is extended in the U-shape. . That is, the first radiating portion 33 is arranged so that the three sides of the patch element surface 21 are surrounded. Further, the second radiating unit 34 is spaced from the top of the power feeding unit 31 in the direction different from the first radiating unit 33 by a predetermined distance in the horizontal direction from the patch element surface 21 of the patch antenna 20 and around the patch element surface 21. It extends in an L shape. That is, the second radiating portion 34 is arranged so that two sides of the patch element surface 21 are surrounded. Accordingly, the first radiating portion 33 and the second radiating portion 34 are arranged so as to substantially surround the patch element surface 21 of the patch antenna 20.

  The first radiating portion 33 and the second radiating portion 34 can be integrally formed by, for example, pressing a sheet metal including the power feeding portion 31 and the short-circuit portion 35.

  In the illustrated example, the power feeding portion 31 of the antenna element 30 is shown to extend in a tapered shape from the radiating portion 32 toward the plate surface of the ground plate 10. More specifically, those having a shape extending in a fan shape in the vertical direction from the plate surface of the ground plate 10 are shown. As a result, the antenna element 30 can be widened. The shape of the power feeding portion 31 is not limited to the illustrated example, and may be any shape that extends in a tapered shape from the radiating portion toward the plate surface of the ground plate, such as an inverted triangle or a trapezoid.

  The composite antenna device of the present invention is configured in this way, so that the antenna performance is improved. Specifically, for example, when the example shown in FIG. 4 is compared with one in which the patch antenna is arranged directly above the ground plate 10 without being lifted from the ground plate, the maximum gain of the patch antenna is improved by about 2 dB. . In addition, high gain can be obtained over a wide range of directivity.

  Another example of the ground plate of the composite antenna device of the present invention will be described with reference to FIG. FIG. 5 is a schematic top view for explaining another example of the ground plate of the composite antenna device of the present invention. In the figure, the same reference numerals as those in FIG. 2 denote the same parts. In FIG. 5, the L-shaped bracket 1 and the cover 2 are omitted. In the illustrated example, only the ground plate 10 is indicated by a solid line, and the antenna element 30 and the patch antenna 20 are indicated by a broken line. In the illustrated example described above, the ground plate 10 has a substantially square shape, but as illustrated, in this example, the ground plate 10 has a rectangular shape. Thus, the ground plate 10 of the composite antenna device of the present invention may not be square. The ground plate 10 is not necessarily uniform, and may have a hole 15 near the center, for example. Accordingly, for example, after inserting the patch antenna 20 from the hole 15 and then inserting the spacer 25, the cover 2 can be closed with the L-shaped bracket 1, and the assembling work is facilitated.

  It should be noted that the composite antenna device of the present invention is not limited to the illustrated examples described above, and it is needless to say that various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 L-shaped bracket 2 Cover 10 Ground plate 15 Hole 20 Patch antenna 21 Patch element surface 25 Spacer 30 Antenna element 31 Feed part 32 Radiation part 33 1st radiation part 34 2nd radiation part 35 Short-circuit part

Claims (8)

A composite antenna device capable of receiving signals of a plurality of frequency bands, the composite antenna device comprising:
A plate-like ground plate that is a finite ground plane;
A patch antenna having a patch element surface on a surface disposed near the center on the ground plate and facing the ground plate;
A feed portion extending so as to rise in a vertical direction from the plate surface of the ground plate, and a predetermined distance in the horizontal direction from the patch element surface of the patch antenna that is bent from the top of the feed portion to be parallel to the ground plate. An antenna element having at least an L-shaped radiating portion around the patch element surface, and the radiating portion is arranged so as to be substantially flush with a vertical height of the patch element surface of the patch antenna. An antenna element;
A composite antenna device comprising:   2. The composite antenna device according to claim 1, wherein the antenna element has a plate shape, and is arranged so that a plate-like surface of the radiating portion faces a plate surface of the ground plate. In the composite antenna device according to claim 1 or 2,
The antenna element further extends from the L-shape so as to surround the patch element surface around the patch element surface at a predetermined interval in the horizontal direction from the patch element surface of the patch antenna, and extends in a U-shape. A composite antenna apparatus characterized by: In the composite antenna device according to claim 1 or 2,
The antenna element is a two-wave compatible element, and the radiating portion extends further from the L shape around the patch element surface in a horizontal direction to the patch element surface of the patch antenna and extends in a U shape. A first radiating portion that extends in an L shape around the patch element surface at a predetermined interval in the horizontal direction from the patch element surface of the patch antenna in a direction different from that of the first radiating portion from the top of the feeding portion. Consisting of the second radiation part,
The composite antenna device, wherein the first radiating portion and the second radiating portion are disposed so as to substantially surround a patch element surface of the patch antenna.   5. The composite antenna device according to claim 1, wherein the patch antenna is electrically conductive from a plate surface of a ground plate such that a patch element surface is substantially flush with a height of a radiation portion of the antenna element. A composite antenna device, wherein the composite antenna device is arranged by being lifted using a spacer of a body or an insulator.   6. The composite antenna device according to claim 5, wherein when the spacer is a conductor, the conductor is conducted to a ground plate. The composite antenna device according to any one of claims 1 to 6, further comprising a cover for accommodating the antenna element and the patch antenna,
The composite antenna device according to claim 1, wherein the patch element surface of the patch antenna is disposed so as to be lowered from the height of the radiation portion of the antenna element to the ground plate side so as not to contact the inner surface of the cover.   8. The composite antenna device according to claim 1, wherein the feeding portion of the antenna element extends in a tapered shape from the radiating portion toward the plate surface of the ground plate. apparatus.