WO2012039465A1

WO2012039465A1 - Antenna system

Info

Publication number: WO2012039465A1
Application number: PCT/JP2011/071664
Authority: WO
Inventors: 裕次郎中山; 磯　洋一; 範行庄司; 正弘楠; 青木　一芳
Original assignee: 古河電気工業株式会社
Priority date: 2010-09-24
Filing date: 2011-09-22
Publication date: 2012-03-29
Also published as: JP2012090251A

Abstract

Capacity forming parts (33a to 33d) for adjusting the resonant frequency of an antenna system (1) are arranged on a front surface (3b) of a dielectric substrate (3) that is the topmost surface of the antenna system (1). As a result, even if the frequency characteristics of the antenna system (1) vary with fluctuations in additional capacity due to manufacturing variations in the permittivity of the dielectric substrate (3), the additional capacity can be easily adjusted by adjusting the areas of the capacity forming parts (33a to 33d) facing a radiation conductor (31) through trimming of the capacity forming parts (33a to 33d), and the frequency characteristics of the antenna system (1) can be adjusted to desired frequency characteristics.

Description

Antenna device

The present invention relates to an antenna device suitable for use in a GPS antenna device or a composite antenna device including a GPS antenna device.

In recent years, navigation devices using GPS (Global Positioning System) and VICS (Vehicle Information and Communication System), ETC (Automatic Toll Collection System) as in-vehicle information devices installed in automobiles : The automatic toll payment system on toll roads using the Electronic Toll Collection system is remarkable. In addition, an emergency communication system that automatically uses a vehicle-mounted telephone system and GPS to automatically transmit a disaster rescue signal when an accident occurs has been put into practical use. The antenna device used in these in-vehicle information devices is required to be small because it is disposed in a limited space of the automobile. For this reason, in a vehicle information device, a planar antenna device is widely used as an antenna device. In particular, for GPS and ETC antenna devices, planar antenna devices are frequently used because of the transmission and reception of circularly polarized radio waves.

As a conventional planar antenna device, a dielectric substrate provided on a ground conductor, a plurality of solder lands provided on the dielectric substrate, and a radiation conductor plate arranged on the dielectric substrate at a predetermined interval And a plurality of leg pieces formed by folding a plurality of locations excluding the central portion of the radiating conductor plate toward the dielectric substrate, and supporting the radiating conductor plate by soldering the plurality of leg pieces to a solder land. Are known. In the planar antenna device having such a configuration, the solder land is opposed to the ground conductor via the dielectric substrate. For this reason, by adding a capacitance between the leg piece soldered to the solder land and the ground conductor, the resonance frequency is lowered, and as a result, the radiation conductor plate and the planar antenna device can be miniaturized. be able to.

However, according to such a configuration of the planar antenna device, it is possible to reduce the size, but the additional capacitance varies due to variations in the solder land solder amount and the soldering area, resulting in the frequency of the planar antenna device. Characteristics may vary. For this reason, in

Patent Documents

1 and 2, the solder land is used by bending the tip of the leg piece facing the dielectric substrate or by providing a capacitor element between the leg piece and the ground conductor. Instead, a method of adding a capacitance between the leg piece and the ground conductor has been proposed.

JP 2008-79009 A JP 2009-21844 A

However, in the planar antenna devices described in

Patent Documents

1 and 2, since the capacitance forming components such as the bent portions of the leg pieces and the capacitors are arranged on the dielectric substrate side, it is not possible to adjust the capacitance value after assembly. difficult. Therefore, according to the planar antenna device described in

Patent Documents

1 and 2, the additional capacitance is adjusted when the frequency characteristics of the planar antenna device fluctuate due to fluctuations in the additional capacitance due to manufacturing variations in the dielectric constant of the dielectric substrate. This makes it difficult to adjust the frequency characteristics of the planar antenna device.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an antenna device in which an additional capacity can be easily adjusted.

In order to solve the above problems and achieve the object, an antenna device according to a first aspect of the present invention includes a grounding substrate having a grounding conductor plate and a resin disposed at a predetermined distance from the surface of the grounding substrate. A radiation conductor plate provided on a back surface or a front surface side of the resin substrate facing the grounding substrate, and the radiation conductor provided in a plane of the resin substrate on which the radiation conductor plate is provided. And a capacitance forming portion that electromagnetically couples with the plate to form a capacitive element between the radiation conductor plate.

In order to solve the above problems and achieve the object, an antenna device according to a second aspect of the present invention includes a grounding substrate having a grounding conductor plate, and a resin disposed at a predetermined distance from the surface of the grounding substrate. A substrate, a radiation conductor plate provided on the back surface or the surface side of the resin substrate facing the ground substrate, and a surface facing the surface of the resin substrate on which the radiation conductor plate is provided. And a capacitance forming part that electromagnetically couples with the radiation conductor plate and forms a capacitive element between the radiation conductor plate.

The antenna device according to the present invention can easily adjust the additional capacitance even when the additional capacitance varies due to manufacturing variations in the dielectric constant of the ground substrate and the resin substrate.

FIG. 1 is a perspective view showing a configuration of an antenna apparatus according to the first embodiment of the present invention. FIG. 2 is a plan view of the antenna device for explaining a method of adjusting the additional capacitance. FIG. 3 is a plan view of the antenna device for explaining the adjustment method of the additional capacitance. 4 is a perspective view showing a configuration of a modification of the antenna device shown in FIG. FIG. 5 is a plan view of the antenna device for explaining the adjustment method of the additional capacitance. FIG. 6 is a perspective view showing the configuration of the antenna device according to the second embodiment of the present invention. FIG. 7 is a perspective view showing a configuration of a modification of the antenna device shown in FIG. FIG. 8 is a perspective view showing a configuration of a modified example of the antenna device shown in FIG. FIG. 9 is a perspective view showing a configuration of a modified example of the antenna device shown in FIG. FIG. 10 is a perspective view showing a configuration of a modification of the antenna device shown in FIG. FIG. 11 is a perspective view showing a configuration of a modified example of the antenna device shown in FIG.

Hereinafter, the configuration of the antenna device according to the first and second embodiments of the present invention will be described with reference to the drawings.

First Embodiment First, the configuration of an antenna device according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 5.

FIG. 1 is a perspective view showing a configuration of an antenna device according to a first embodiment of the present invention. As shown in FIG. 1, an antenna device 1 according to a first embodiment of the present invention includes a pair of

dielectric substrates

2 and 3 formed in a quadrangular shape, and the pair of

dielectric substrates

2 and 3 are spaced apart from each other by a predetermined distance. They are spaced apart from each other. The pair of

dielectric substrates

2 and 3 are formed of a resin material such as glass epoxy resin.

A ground conductor plate 21 formed of a sheet metal part is disposed on the back side 2b of the dielectric substrate 2. A radiation conductor plate 31 formed of copper foil or the like is disposed on the back surface 3a side of the dielectric substrate 3 facing the dielectric substrate 2. The radiating conductor plate 31 is formed with a slit-shaped perturbation portion 31c so that circularly polarized radio waves can be transmitted and received. A conductive member 41 erected on the surface 2 a side of the dielectric substrate 2 facing the dielectric substrate 3 is connected to the radiation conductor plate 31. A power supply signal supplied from a power supply pin (not shown) to the conductive member 41 is supplied to the radiation conductor plate 31 via the conductive member 41. That is, the radiating conductor plate 31 is directly fed by a one-point feeding method.

At the four corners on the surface side 3b of the dielectric substrate 3, four triangular

capacitance forming portions

33a, 33b, 33c, 33d formed by sheet metal parts are arranged. That is, the four capacitance forming portions 33a to 33d are provided at an interval of approximately 90 degrees with the center position of the dielectric substrate 3 (radiating conductor plate 31) as an axis. The four capacitance forming portions 33a to 33d are connected to one end portions of rod-like

conductive members

42a, 42b, 42c, and 42d that penetrate the dielectric substrate 3. The other end portions of the conductive members 42 a to 42 d are fixed to the dielectric substrate 2 with a solder material 43. The conductive members 42a to 42d have a function of supporting the dielectric substrate 3 at a predetermined distance from the surface 2a of the dielectric substrate 2 and a function of grounding the capacitor forming portions 33a to 33d. Thus, the four capacitance forming portions 33 a to 33 d are electromagnetically coupled to the radiation conductor plate 31 to form a capacitive element between the radiation conductor plate 31. As a result, the resonance frequency of the antenna device 1 is lowered, and the antenna device 1 can be downsized.

As is apparent from the above description, in the antenna device 1 according to the first embodiment of the present invention, the capacity forming portions 33a to 33d for adjusting the resonance frequency of the antenna device 1 are the outermost surfaces of the antenna device 1. It is disposed on the surface side 3 b of the dielectric substrate 3. Therefore, according to such a configuration, even when the frequency characteristics of the antenna device 1 fluctuate due to fluctuations in the additional capacitance due to manufacturing variations in the dielectric constant of the dielectric substrate 3, as shown in FIG. By trimming the capacitance forming portions 33a to 33d, the opposing area of the capacitance forming portions 33a to 33d with respect to the radiation conductor plate 31 is adjusted, thereby easily adjusting the additional capacitance and changing the frequency characteristics of the antenna device 1 to the desired frequency characteristics. Can be adjusted.

In the antenna device 1 according to the first embodiment of the present invention, the capacitance forming portions 33a to 33d have a triangular shape. However, the capacitance forming portions 33a to 33d have a shape other than the triangular shape. May be. For example, as shown in FIG. 3, a plurality of protrusions 34 protruding in the in-plane direction of the surface 3b of the dielectric substrate 3 are provided in the capacitance forming parts 33a to 33d, and the length and number of the protrusions 34 to be trimmed are adjusted. Accordingly, the additional capacity may be adjusted.

In the antenna device 1 according to the first embodiment of the present invention, the radiating conductor plate 31 and the capacitance forming portions 33a to 33d are provided on the back surface 3a side and the front surface side 3b of the dielectric substrate 3, respectively. As shown, capacitance forming portions 33a to 33d and a radiating conductor plate 31 are provided on the back surface 3a side and the front surface side 3b of the dielectric substrate 3, respectively, and the radiating conductor plate 31 is trimmed to thereby form a capacitance forming portion 33a for the radiating conductor plate 31. The opposing area of ~ 33d may be adjusted. The dielectric substrate 3 is supported by the dielectric substrate 2, the conductive members 42a to 42d, and the capacitance forming portions 33a to 33d. Specifically, in this case, as shown in FIG. 5, protrusions 35 are provided at the four corners of the radiation conductor plate 31 facing the capacitor forming portions 33a to 33d, and the length and number of the protrusions 35 to be trimmed are adjusted. Thus, the facing area of the capacitance forming portions 33a to 33d with respect to the radiation conductor plate 31 is adjusted.

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

FIG. 6 is a perspective view showing the configuration of the antenna device according to the second embodiment of the present invention. As shown in FIG. 6, the antenna device 1 according to the second embodiment of the present invention includes a pair of

dielectric substrates

2 and 3 formed in a quadrangular shape, and the pair of

dielectric substrates

2 and 3 are formed of a resin material such as glass epoxy resin.

A ground conductor plate 21 formed of a sheet metal part is disposed on the back side 2b of the dielectric substrate 2. A Wilkinson distributor 22 is provided on the surface 2 a side of the dielectric substrate 2 facing the dielectric substrate 3. The Wilkinson distributor 22 has two

output portions

22a and 22b which are in a positional relationship 90 degrees apart from each other within the surface 2a of the dielectric substrate 2. A power supply signal supplied from one power supply pin (not shown) to Wilkinson distributor 22 is output from

output units

22a and 22b with the same amplitude and a phase difference of 90 degrees. By using the Wilkinson distributor 22, it is possible to use only one power supply pin as an interface with a receiving circuit (not shown). The positions of the

output units

22a and 22b may be adjusted by adjusting the pattern of the Wilkinson distributor 22.

On the back surface 3a side of the dielectric substrate 3 facing the dielectric substrate 2, a radiation conductor plate 31 formed of copper foil or the like is disposed. On the surface side 3b of the dielectric substrate 3, a pair of

power supply pads

32a and 32b formed of a copper foil or the like is disposed. The pair of

power supply pads

32a and 32b are disposed at positions corresponding to the

output portions

22a and 22b, respectively. The

power supply pads

32 a and 32 b and the

output portions

22 a and 22 b are electrically connected by rod-like

conductive members

41 a and 41 b that penetrate the dielectric substrate 3. Thus, the power supply signals output from the

output units

22a and 22b are supplied to the

power supply pads

32a and 32b via the

conductive members

41a and 41b, and are formed between the

power supply pads

32a and 32b and the radiation conductor plate 31. Capacitive power is supplied to the radiation conductor plate 31 through the capacitive element. That is, the radiating conductor plate 31 is capacitively fed by a two-point feeding method. The pair of

power supply pads

32a and 32b functions as a capacitive power supply unit according to the present invention.

capacitance forming portions

33a, 33b, 33c, 33d formed by sheet metal parts are arranged. That is, the four capacitance forming portions 33a to 33d are provided at an interval of approximately 90 degrees with the center position (radiation conductor plate 31) of the dielectric substrate 3 as an axis. The four capacitance forming portions 33a to 33d are connected to one end portions of rod-like

conductive members

42a, 42b, 42c, and 42d that penetrate the dielectric substrate 3. The other end portions of the conductive members 42 a to 42 d are fixed to the ground conductor plate 21 with a solder material 43. The conductive members 42a to 42d have a function of supporting the dielectric substrate 3 at a predetermined distance from the surface 2a of the dielectric substrate 2 and a function of grounding the capacitor forming portions 33a to 33d. Thus, the four capacitance forming portions 33 a to 33 d are electromagnetically coupled to the radiation conductor plate 31 to form a capacitive element between the radiation conductor plate 31. As a result, the resonance frequency of the antenna device 1 is lowered, and the antenna device 1 can be downsized.

As is clear from the above description, in the antenna device 1 according to the second embodiment of the present invention, the capacity forming portions 33a to 33d for adjusting the resonance frequency of the antenna device 1 are the outermost surfaces of the antenna device 1. It is disposed on the surface side 3 b of the dielectric substrate 3. Therefore, according to such a configuration, even when the frequency characteristics of the antenna device 1 fluctuate due to fluctuations in the additional capacitance due to manufacturing variations in the dielectric constant of the dielectric substrate 3, the capacitance forming portions 33a to 33d can be provided. By adjusting the opposing area of the capacitance forming portions 33a to 33d with respect to the radiation conductor plate 31 by trimming, the additional capacitance can be easily adjusted and the frequency characteristic of the antenna device 1 can be adjusted to a desired frequency characteristic.

In the antenna device 1 according to the second embodiment of the present invention, the radiation conductor plate 31 is fed by the two-point feeding method, so that the band of the antenna device 1 can be widened. In the antenna device 1 according to the embodiment of the present invention, the

power feeding pads

32a and 32b are disposed on the surface side 3b of the dielectric substrate 3 which is the outermost surface of the antenna device 1, and therefore the

power feeding pads

32a and 32b are arranged. By adjusting the opposing area of the

power supply pads

32a and 32b with respect to the radiation conductor plate 31 by trimming, the impedance at the time of power supply can be easily adjusted.

In the antenna device 1 according to the second embodiment of the present invention, the capacitance forming portions 33a to 33d and the radiation conductor plate 31 are disposed on the front surface 3b side and the back surface 3a side of the dielectric substrate 3, respectively. As shown in FIG. 7, the capacitance forming portions 33a to 33d and the radiation conductor plate 31 may be disposed on the back surface 3a side and the front surface 3b side of the dielectric substrate 3, respectively. In the configuration shown in FIG. 7, the additional capacitance is adjusted by trimming the radiation conductor plate 31 disposed on the outermost surface of the antenna device 1 to adjust the facing area of the radiation conductor plate 31 with respect to the capacitance forming portions 33a to 33d. The frequency characteristic of the antenna device 1 can be adjusted to a desired frequency characteristic. The dielectric substrate 3 is supported by the dielectric substrate 2, the conductive members 42a to 42d, and the capacitance forming portions 33a to 33d.

In the antenna device 1 according to the second embodiment of the present invention, the radiating conductor plate 31 and the capacitance forming portions 33a to 33d are provided on the back surface 3a side and the front surface side 3b of the dielectric substrate 3, respectively. As shown, capacitance forming portions 33a to 33d and a radiating conductor plate 31 are provided on the back surface 3a side and the front surface side 3b of the dielectric substrate 3, respectively, and the radiating conductor plate 31 is trimmed to thereby form a capacitance forming portion 33a for the radiating conductor plate 31. The opposing area of ~ 33d may be adjusted. Specifically, in this case, as shown in FIG. 5, protrusions 35 are provided at the four corners of the radiation conductor plate 31 facing the capacitor forming portions 33a to 33d, and the length and number of the protrusions 35 to be trimmed are adjusted. Thus, the facing area of the capacitance forming portions 33a to 33d with respect to the radiation conductor plate 31 is adjusted.

According to the configuration shown in FIG. 8, when the

power supply pads

32a and 32b are provided on the surface 3b side of the dielectric substrate 3, the area of the radiation conductor plate 31 is reduced, so that the

power supply pads

32a and 32b are connected to the dielectric substrate. 3 is preferably provided on the back surface 3a side. Further, the opening 44 may be formed in the radiation conductor plate 31 and the dielectric substrate 3 so that the mounting state of the Wilkinson distributor 22 can be confirmed.

In the antenna device 1 according to the second embodiment of the present invention, the

power supply pads

32a and 32b are arranged on the front surface 3b side of the dielectric substrate 3. However, as shown in FIG.

Cutout portions

31a and 31b may be formed by cutting out the radiation conductor plate 31 disposed on the side, and the

power supply pads

32a and 32b may be disposed in the

cutout portions

31a and 31b. However, according to such a configuration, the area of the radiating conductor plate 31 is reduced as compared with the configuration shown in FIG. 6, so that the antenna characteristics may be deteriorated.

In the antenna device 1 according to the second embodiment of the present invention, the radiating conductor plate 31 is disposed on the back surface 3a side of the dielectric substrate 3. However, as shown in FIG. The radiation conductor plate 31 may be arranged on the surface 3b side of the dielectric substrate 3 so as not to contact the portions 33a to 33d. Further, as shown in FIG. 11, instead of the capacitance forming portions 33a to 33d shown in FIG. 10,

pad portions

36a, 36b, 36c, and 36d that are in contact with the conductive members 42a to 42d, the radiation conductor plate 31, and the pad portion.

Capacitor chips

37a, 37b, 37c, and 37d that connect 36a to 36d may be provided. In the configuration shown in FIG. 8, when the frequency characteristics of the antenna device 1 fluctuate due to fluctuations in the additional capacitance due to manufacturing variations in the dielectric constant of the dielectric substrate 3, the capacitor chips 37a to 37d are replaced with other capacitor chips having different capacities. The additional capacity can be easily adjusted by appropriately changing to.

As mentioned above, although the embodiment to which the invention made by the present inventor is applied has been described, the present invention is not limited by the description and the drawings that form part of the disclosure of the present invention according to this embodiment. For example, the antenna device according to the present invention uses a satellite navigation system GALILEO of the Russian satellite navigation system GLONASS (Global Navigation Satellite System), the European Union (EU) and the European Space Agency (ESA), a satellite in the United States. It can be applied to SDARS (Satellite Digital Audio Radio Service) etc., which is a service by digital broadcasting. That is, other embodiments, examples, operational techniques, and the like made by those skilled in the art based on the present embodiment are all included in the scope of the present invention.

The present invention can be used for a GPS antenna device and a composite antenna device including a GPS antenna device.

DESCRIPTION OF SYMBOLS 1

Antenna apparatus

2, 3 Dielectric board | substrate 21 Grounding conductor plate 22 Wilkinson type | mold divider |

distributor

22a, 22b Output part 31

Radiation conductor plate

31a,

31b Notch part

32a,

32b Feeding pad

33a, 33b, 33c, 33d

Capacitance formation part

34, 35

Protrusions

36a, 36b, 36c,

36d Pad portions

37a, 37b, 37c,

37d Capacitor chips

41a, 41b, 42a, 42b, 42c, 42d Conductive members 44 Openings

Claims

A grounding substrate having a grounding conductor plate;
A resin substrate disposed at a predetermined distance from the surface of the ground substrate;
A radiation conductor plate provided on the back side or the front side of the resin substrate facing the ground substrate;
A capacitance forming portion that is provided in a plane of the resin substrate on which the radiation conductor plate is provided, and that forms a capacitive element between the radiation conductor plate by electromagnetic coupling with the radiation conductor plate;
An antenna device comprising:
A grounding substrate having a grounding conductor plate;
A resin substrate disposed at a predetermined distance from the surface of the ground substrate;
A radiation conductor plate provided on the back side or the front side of the resin substrate facing the ground substrate;
A capacitance forming portion provided in a surface opposite to the surface of the resin substrate on which the radiation conductor plate is provided, and electromagnetically coupled to the radiation conductor plate to form a capacitive element between the radiation conductor plate; ,
An antenna device comprising:
The said capacitive element part is arrange | positioned by the 90-degree space | interval of the center position of the said radiation conductor board at the vicinity of the edge part of the in-plane direction of this radiation conductor board. Antenna device.
The antenna device according to any one of claims 1 to 3, wherein the frequency characteristics can be adjusted by trimming the capacitive element section.
The antenna device according to any one of claims 1 to 3, wherein the frequency characteristic can be adjusted by trimming the radiation conductor plate.
The antenna device according to any one of claims 1 to 5, wherein the radiation conductor plate is provided with a power feeding unit that performs two-point power feeding with substantially the same amplitude and a phase difference of approximately 90 degrees.
The antenna device according to any one of claims 1 to 6, wherein the grounding conductor plate and the capacitive element portion are configured by sheet metal parts and support the resin substrate.
The antenna device according to claim 6, further comprising a circuit board including the ground substrate constituting the power feeding unit.
The antenna device according to claim 8, wherein an output position of the power feeding unit can be selected by adjusting a pattern of the circuit board.
The antenna device according to claim 8 or 9, wherein the resin substrate and the circuit substrate are supported by a sheet metal part constituting the capacitive element portion.
The antenna device according to any one of claims 8 to 10, wherein the radiation conductor plate has an opening.