JP2013058893A - Antenna device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite antenna device that implements improved reception sensitivity to a GPS signal while suppressing an increase in size.SOLUTION: The antenna device includes a film antenna for receiving a digital terrestrial signal, and a rectangular patch antenna for receiving a GPS signal. The film antenna includes a ground pattern extending in a straight line, and a pair of feed elements extending in a direction perpendicular to the direction of extension of the ground pattern at a predetermined interval from one end portion of the ground pattern. The patch antenna is arranged within a corner region formed by the ground pattern and the pair of feed elements such that a pair of parallel sides of a main surface of the patch antenna are parallel in the direction of extension of the ground pattern.

Description

  The present invention relates to an antenna device, and more particularly to an antenna device mounted on a vehicle such as an automobile.

Conventionally, navigation systems mounted on vehicles such as automobiles are known to be able to view digital terrestrial television broadcasts, and vehicles receive not only antenna devices that receive GPS signals but also digital terrestrial signals. An antenna device is also installed.
In recent years, a composite antenna device in which a GPS antenna and a terrestrial digital antenna are integrated has been developed (see, for example, Patent Document 1).

JP 2011-77826 A

By the way, in the antenna device described in Patent Document 1, both the GPS antenna and the terrestrial digital antenna are in the form of a film. There was a risk that the condition would be damaged.
For this reason, the subject of this invention is improving the receiving sensitivity performance of a GPS signal, suppressing the enlargement of a composite-type antenna apparatus.

The antenna device according to claim 1 is:
A film antenna for receiving terrestrial digital signals;
A substantially rectangular plate-shaped patch antenna for receiving satellite signals;
The film antenna is
A linearly extending ground pattern;
A feeding element extending in a direction perpendicular to the extending direction of the ground pattern with a predetermined interval from one end of the ground pattern,
The patch antenna is arranged inside a corner portion formed by the ground pattern and the power feeding element so that a pair of sides parallel to each other on the main surface of the patch antenna are parallel to the extending direction of the ground pattern. It is characterized by being.

The invention according to claim 2 is the antenna device according to claim 1,
The patch antenna is arranged inside the corner so as not to overlap each of the ground pattern and the feeding element.

The invention according to claim 3 is the antenna device according to claim 1 or 2,
A film antenna substrate portion on which the amplification circuit components for the film antenna are mounted;
A case portion having a bottom case and a top case covering the bottom case,
The patch antenna includes a patch antenna substrate portion on which an antenna element and an amplifier circuit component are mounted.
The case portion has a patch storage region for storing the patch antenna, and a film storage region for storing the film antenna substrate portion.

  ADVANTAGE OF THE INVENTION According to this invention, the reception sensitivity performance of a GPS signal can be improved, suppressing the enlargement of a composite type antenna apparatus.

It is a perspective view which shows schematic structure of the antenna device which concerns on this embodiment. It is a disassembled perspective view of the antenna apparatus shown in FIG. It is sectional drawing which shows schematic structure of the main-body part with which the antenna apparatus of FIG. 1 is equipped. It is a front view which shows schematic structure of the film antenna with which the antenna apparatus of FIG. 1 is equipped. It is a front view which shows the positional relationship of the film antenna and patch antenna which concern on this embodiment. It is explanatory drawing which shows the state which installed the antenna apparatus of FIG. 1 on the windshield of a motor vehicle by 4 divers, for example.

  The best mode for carrying out the present invention will be described below with reference to the drawings. However, although various technically preferable limitations for implementing the present invention are given to the embodiments described below, the scope of the invention is not limited to the following embodiments and illustrated examples.

  FIG. 1 is a perspective view showing a schematic configuration of an antenna device according to the present embodiment, and FIG. 2 is an exploded perspective view. As shown in FIGS. 1 and 2, the antenna device 1 includes a main body 2 and a film antenna 3 that receives a terrestrial digital signal.

  FIG. 3 is a cross-sectional view showing a schematic configuration of the main body 2. As shown in FIGS. 2 and 3, the main body 2 includes a patch antenna 4, a substrate portion 5 of the patch antenna 4, a substrate portion 6 of the film antenna 3, and a case portion 7 for storing them. .

The patch antenna 4 is an antenna that receives a satellite signal such as a GPS signal. The patch antenna 4 passes through a substantially rectangular plate-shaped antenna element 41 made of, for example, ceramics, and a substantially central portion of the antenna element 41, and is on the receiving surface side. And a power supply pin 42 soldered. A ground 43 is formed on the surface of the antenna element 41 opposite to the reception surface.
The antenna element 41 has, for example, a square plate shape of 20 × 20 × 4 t [mm]. Note that the shape of the antenna element 41 does not have to be a perfect rectangular plate shape, and may be chamfered as shown in FIG.

  The substrate portion 5 of the patch antenna 4 is a substrate portion for a patch antenna according to the present invention. The substrate 51 and a circuit such as an amplifier circuit component (LNA (Low Noise Amplifier)) for the patch antenna 4 are used. Parts (not shown). A ground 52 is formed on the surface of the substrate 51 opposite to the surface on which the circuit components are mounted, and the patch antenna 4 is fixed by a double-sided tape (not shown). One end of the GPS coaxial cable 8 is connected to the surface of the substrate 51 on which circuit components are mounted.

  The substrate portion 6 of the film antenna 3 is a substrate portion for a film antenna according to the present invention, and includes a substrate 61, fingers 62 that electrically connect the substrate 61 and the film antenna 3, and an amplifier circuit for the film antenna 3, for example. Circuit components (not shown) such as components (LNA). The finger 62 is attached to the surface of the substrate 61 opposite to the surface on which circuit components are mounted. Further, one end of the terrestrial digital coaxial cable 9 is connected to the surface of the substrate 61 on which the circuit components are mounted.

The case portion 7 is made of resin and includes a bottom case 71, a top case 72, and a pedestal 73.
The bottom case 71 has a patch storage area 711 for storing the patch antenna 4 and the substrate section 5 of the patch antenna 4, and a film storage area 712 for storing the substrate section 6 of the film antenna 3.
In the patch storage area 711, a protrusion 713 that abuts on the receiving surface of the patch antenna 4 is formed. The antenna element 41 is raised by the projection 713, and interference between the solder portion 44 of the antenna element 41 and the bottom portion of the bottom case 71 is prevented. As a result, the patch antenna 4 is positioned and rattling after storage is suppressed.
An opening 714 for exposing the finger 62 is formed at the bottom of the film storage area 712. A film antenna substrate 61 is fixed to the bottom of the film storage area 712 with a double-sided tape (not shown).
A claw portion 715 that engages with the top case 72 is formed inside the wall portion of the bottom case 71. A recess 716 that engages with the pedestal 73 is formed outside the wall of the bottom case 71.
Further, a through hole 717 in which a screw head of a screw 15 described later is disposed is formed in the bottom portion of the bottom case 71.

The top case 72 surrounds the bottom case 71 and closes it. A protrusion 721 that contacts the substrate 51 of the patch antenna 4 is formed inside the top case 72. The patch antenna 4 is fixed in the patch storage area 711 by the protrusion 721 pressing the substrate 51.
A convex portion 722 extending to the through hole 717 is formed inside the top case 72. The convex portion 722 is formed with a screw hole communicating with the through hole 717, and the top case 72 is fixed to the bottom case 71 by screwing the screw 15 into the through hole 717 and the screw hole.
Further, the top case 72 is formed with an engaging portion 723 that extends toward the claw portion 715 of the bottom case 71 and engages with the claw portion 715. If the engagement between the engagement portion 723 and the claw portion 715 is released, the top case 72 can be removed from the bottom case 71.

  The pedestal 73 supports the bottom case 71 and the top case 72. The pedestal 73 is formed with an engaging portion 731 that extends to the concave portion 716 of the bottom case 71 and engages with the concave portion 716. If the engagement between the engaging portion 731 and the recess 716 is released, the bottom case 71 can be removed from the pedestal 73. The pedestal 73 has an opening 732 for exposing the finger 62. And the base 73 is affixed via the double-sided tape 74 with respect to the film antenna 3 affixed on the window glass of the vehicle. The double-sided tape 74 also has an opening 741 for exposing the finger 62.

FIG. 4 is a front view showing a schematic configuration of the film antenna 3. As shown in FIG. 4, the film antenna 3 has a predetermined light transmittance as a whole, and includes a first ground pattern 31, a second ground pattern 32, and a pair of power feeding elements 33 and 34. Yes.
The first ground pattern 31 is formed so as to extend linearly from the feeding point 35. The second ground pattern 32 is formed to extend from the feeding point 35 along a direction orthogonal to the extending direction of the first ground pattern 31.
The pair of power feeding elements 33 and 34 are formed to extend from the power feeding point 36 along a direction orthogonal to the extending direction of the first ground pattern 31. Here, since the feeding point 36 for the feeding elements 33 and 34 is arranged to be spaced apart from one end of the first ground pattern 31 downward in FIG. 3, the pair of feeding elements 33 and 34 is also the first ground. The pattern 31 is disposed at a predetermined interval from one end of the pattern 31.

FIG. 5 is a front view showing the positional relationship between the film antenna 3 and the patch antenna 4. As shown in FIG. 5, the patch antenna 4 has a corner portion 40 formed by the first ground pattern 31 and the pair of feed elements 33 and 34 so as not to overlap the first ground pattern 31 and the pair of feed elements 33 and 34. It is arranged inside. The patch antenna 4 is arranged such that a pair of sides 41 a and 41 b parallel to each other on the main surface of the antenna element 41 are parallel to the extending direction of the first ground pattern 31.
Further, the fingers 62 are in contact with the feeding points 35 and 36, respectively. Thereby, the film antenna 3 and the substrate part 6 of the film antenna 3 are electrically connected via the fingers 62.

As described above, according to the present embodiment, the patch antenna 4 is configured so that the pair of sides 41a and 41b parallel to each other on the main surface of the antenna element 41 are parallel to the extending direction of the first ground pattern 31. Since it arrange | positions inside the corner | angular part 40 which the 1st ground pattern 31 and a pair of electric power feeding elements 33 and 34 make, the electric power feeding points 35 and 36 of the film antenna 3 and the patch antenna 4 are arrange | positioned as closely as possible. can do.
FIG. 6 is an explanatory diagram showing a state in which the antenna device 1 is installed on the windshield of an automobile, for example, with 4 divers. The antenna device 1 that combines the GPS patch antenna 4 and the digital terrestrial broadcasting film antenna 3 according to the present embodiment is arranged at any one of the upper side, the left side, and the right side of the windshield F. The other antenna device 1 </ b> A may be configured to have only the film antenna 3 for digital terrestrial broadcasting. In this case, each antenna device 1, 1 </ b> A is attached such that the first ground pattern 31 is along one side of the windshield F. Since the main body 2 of the antenna device 1 is not light transmissive, it must be contained within a predetermined range H on the periphery of the windshield F. For this reason, if the case part 7 becomes large, the case part 7 protrudes outside the predetermined range H, thereby blocking the driver's field of view. By the way, as described above, the substrate portion 6 of the film antenna 3 in the antenna device 1 is disposed so as to overlap the feeding points 35 and 36 of the film antenna 3, and the substrate portion 5 of the patch antenna 4 is overlapped with the patch antenna 4. Be placed. That is, if the feeding points 35 and 36 and the patch antenna 4 are separated from each other, the case portion 7 becomes large. On the other hand, when the feeding points 35 and 36 and the patch antenna 4 are close to each other as in the antenna device 1 of the present embodiment, an increase in the size of the case portion 7 can be suppressed.
Since the patch antenna 4 has higher reception sensitivity performance than the GPS film antenna used in the conventional composite antenna device, the reception sensitivity performance of the GPS signal of the entire antenna device 1 may be improved. Is possible.

  In addition, if the patch antenna 4 itself is reduced in size, it is of course possible to more effectively suppress an increase in the size of the case portion 7, but if that is the case, an expensive patch antenna must be employed, which is not preferable. The ceramic patch antenna 4 exemplified in the present embodiment is inexpensive but is compact to some extent. If this ceramic patch antenna 4 is adopted and arranged inside the corner portion 40, it is easy to realize the case portion 7 that falls within the predetermined range H while suppressing the manufacturing cost.

In addition, since the patch antenna 4 is disposed inside the corner portion 40 so as not to overlap the first ground pattern 31 and the pair of power feeding elements 33 and 34, the film antenna 3 and the patch antenna 4 are connected at the time of signal reception. It is possible to suppress the reception sensitivity from becoming unstable due to interference.
For this reason, the patch antenna 4 can be kept close to the first ground pattern 31 and the pair of power feeding elements 33 and 34 in a range that does not overlap the first ground pattern 31 and the pair of power feeding elements 33 and 34. In addition, it is preferable.

  Further, since the bottom case 71 is detachable with respect to the pedestal 73, when the repair work of the patch antenna 4 or each of the board portions 5 and 6 is necessary, the bottom case 71 is removed from the pedestal 73 and the repair work is performed. Can do. If the pedestal 73 and the bottom case 71 are fixed, the double-sided tape 74 must be peeled off from the windshield, and a new double-sided tape 74 is required again after the repair work. However, if the bottom case 71 is detachable from the pedestal 73, the bottom case 71 may be removed from the pedestal 73 and repaired, and then the bottom case 71 may be attached to the pedestal 73, and a new double-sided tape 74 is prepared. You don't have to.

Note that the present invention is not limited to the above embodiment, and can be modified as appropriate.
For example, although the film antenna 3 provided with the second ground pattern 32 has been illustrated and described in the above embodiment, if the positional relationship between the first ground pattern 31 and the pair of power feeding elements 33 and 34 is not changed, the second ground It is also possible to use a film antenna in which the pattern 32 is omitted.
The second ground pattern 32 may be provided between the pair of power feeding elements 33 and 34 and the patch antenna 4. Even in this case, it is preferable that the patch antenna 4 does not overlap the second ground pattern 32.
In the above embodiment, the film antenna 3 including the pair of feeding elements 33 and 34 is described as an example. However, the configuration of the present invention can be applied to a film antenna having one feeding element. .

  Moreover, although the case where the board | substrate 51 of the patch antenna 4 and the board | substrate 61 of the film antenna 3 were separate bodies was illustrated in the said embodiment, both may be integrated.

DESCRIPTION OF SYMBOLS 1 Antenna apparatus 2 Main-body part 3 Film antenna 4 Patch antenna 5 Board | substrate part (Patch antenna board | substrate part)
6 Substrate (film antenna substrate)
7 Case part 31 First ground pattern (ground pattern)
32 Second ground pattern 33, 34 Feed element 35, 36 Feed point 40 Corner 41 Antenna element 41a, 41b Side 42 Feed pin 71 Bottom case 72 Top case 73 Base 74 Double-sided tape 711 Patch storage area 712 Film storage area F Windshield H Predetermined range

Claims (3)

A film antenna for receiving terrestrial digital signals;
A substantially rectangular plate-like patch antenna that receives a hygiene signal,
The film antenna is
A linearly extending ground pattern;
A feeding element extending in a direction perpendicular to the extending direction of the ground pattern with a predetermined interval from one end of the ground pattern,
The patch antenna is arranged inside a corner portion formed by the ground pattern and the power feeding element so that a pair of sides parallel to each other on the main surface of the patch antenna are parallel to the extending direction of the ground pattern. An antenna device characterized by being made. The antenna device according to claim 1, wherein
The antenna device, wherein the patch antenna is disposed inside the corner so as not to overlap each of the ground pattern and the feeding element. The antenna device according to claim 1 or 2,
A film antenna substrate portion on which the amplification circuit components for the film antenna are mounted;
A case portion having a bottom case and a top case covering the bottom case,
The patch antenna includes a patch antenna substrate portion on which an antenna element and an amplifier circuit component are mounted.
The antenna device according to claim 1, wherein the case portion includes a patch storage region for storing the patch antenna and a film storage region for storing the film antenna substrate portion.

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