JP2002252515A - Antenna device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of electrolytic coupling that prevents required antenna characteristics from being maintained when a plurality of independently functioning antennas are arranged adjacently. SOLUTION: A plurality of the single antennas 2 and 3 functioning as the independent antennas are arranged adjacently. Side-face grounding electrodes 12 at ground potential are mounted on the side faces of the opposed base bodies 4 and 5 of the single antenna 2 and the single antenna 3. According to the constitution, the extent of an electric field in the direction of the adjacent single antennas 2 and 3 is inhibited, and electrolytic coupling between the adjacent single antennas 2 and 3 is weakened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna device comprising a plurality of single antennas.

[0002]

2. Description of the Related Art In recent years, with the advanced development of automobile traffic, GPS (Global Positioning System) using radio waves of artificial satellites has been developed.
g System), and ET that automatically collects tolls from vehicles running on road traffic
C (Electric Toll Collection) is being used. Since these systems use radio waves of different frequencies, they are respectively configured as individual wireless communication devices, but are preferably configured as one wireless communication device in order to be arranged at an appropriate position in a vehicle.

When a plurality of single antennas are arranged close to each other, electric field coupling occurs between the single antennas, and the characteristics of one or both antennas deteriorate. For this reason, conventionally, by increasing the relative dielectric constant of the base constituting each single antenna,
It is known that the interference between single antennas is reduced to improve antenna characteristics (1990-ITE Autumn National Convention, B-61).

[0004]

However, when the relative dielectric constant of the base of the single antenna is excessively increased, the electrical Q of the resonance characteristic of the single antenna increases, and the single antenna having the required frequency bandwidth is required. It is difficult to configure an antenna.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an antenna device which secures necessary antenna characteristics and reduces the distance between antennas to reduce the size. is there.

[0006]

Means for Solving the Problems In order to achieve the above object, the present invention provides means for solving the problems with the following constitution. That is, the antenna device according to the first invention includes a dielectric base having a feed electrode, a radiation electrode provided on one main surface of the base, and a ground antenna provided on the other main surface. In addition to the above arrangement, at least one base of the single antenna is provided with a side surface ground electrode electrically connected to the ground electrode on a side surface facing the adjacent single antenna, thereby providing means for solving the problem.

According to the present invention, when a plurality of single antennas are arranged close to each other, the side ground electrode which becomes the ground potential is provided on the side of the base opposite to the single antenna.
Most of the lines of electric force generated from the radiation electrode terminate at the side ground electrode, and the ratio of coupling to the radiation electrode of the adjacent single antenna is reduced. In other words, the spread of the electric field generated from the radiation electrode of the single antenna is significantly smaller than that of the side of the base body without the side ground electrode, and the electric field coupling with the adjacent single antenna is weakened.

Therefore, a plurality of single antennas can be arranged closer to each other, and the width of the base of the single antenna can be reduced. Further, since it is not necessary to make the relative dielectric constant of the base of the single antenna excessively high, a necessary and sufficient frequency bandwidth as a single antenna can be secured. Here, the single antenna is an antenna having a base and an electrode structure necessary for an antenna and functioning as an independent antenna.

The antenna device according to a second aspect of the present invention is characterized in that, in the above-described invention, a plurality of single antennas are excited at a resonance frequency in the same frequency band.

By adopting this configuration, it can be used as a transmitting / receiving antenna in a plurality of communication systems corresponding to the number of single antennas, and a configuration in which transmission and reception are performed by separate single antennas in one communication system. It becomes possible.

An antenna device according to a third aspect of the present invention includes a rectangular substrate provided with a ground pattern, and two single antennas each formed by providing a radiation base and a feed electrode on a dielectric base. A single antenna is disposed at each end position, and one or both bases of each single antenna are provided with a side surface ground electrode electrically connected to a ground pattern on the opposite side surface. ing.

In this configuration, the size of the substrate on which the single antenna is installed is usually limited by the space in the housing of the wireless communication device on which the antenna device is mounted. For this reason, by arranging a single antenna at a diagonal position of the substrate, a plurality of single antennas can be arranged as far as possible on a substrate of a limited size. In addition, the base of the single antenna is configured as a rectangular parallelepiped, but the side ground electrode is formed on the closest side of the side of the base.

For example, when there are two side surfaces adjacent to the base of the adjacent single antenna, the side surface ground electrode is provided across the two adjacent side surfaces. At this time, the side surface ground electrode may be provided on the entire side surface of the base body, or may be provided so as to be biased on the side surface portion that faces closely. In any case, due to the synergistic effect of increasing the interval between the single antennas and the installation of the side ground electrode, the spread of the electric field to the adjacent single antenna side is largely suppressed, and the electric field coupling between the single antennas is greatly reduced. be able to.

According to a fourth aspect of the present invention, there is provided an antenna device comprising: a first single antenna having a radiation base and a feed electrode on a dielectric base for exciting at a first resonance frequency; and a radiation base and a feed electrode on the dielectric base. And a second single antenna having a second resonance frequency higher than the first resonance frequency.
The single antenna and the second single antenna are arranged close to each other, and at least a base of the first single antenna is provided with a side surface ground electrode on a side surface facing the second single antenna.

In the present invention, the second single antenna is configured to be higher than the resonance frequency of the first single antenna, but when the harmonics of the first single antenna approximate the resonance frequency of the second single antenna. , Interference with the second single antenna occurs. In this case, by providing a side surface ground electrode on the side surface of the base of the first single antenna facing the second single antenna, electric field coupling with the second single antenna is weakened, and deterioration of the antenna characteristics of the second single antenna is prevented. Can be.

An antenna device according to a fifth aspect of the present invention includes a dielectric base having first and second feed electrodes, and a first radiation electrode electrically coupled to the first feed electrode on one main surface of the base. And a second radiating electrode electrically coupled to the second feeding electrode, a dividing groove is provided between the first radiating electrode and the second radiating electrode of the base, and a side ground electrode is provided in the dividing groove. The side ground electrode is electrically connected to a ground electrode provided on the other main surface of the base.

According to the invention having this configuration, one base is provided with:
Two radiating electrodes are provided side by side to constitute a single antenna functioning individually. For this reason, the electric field coupling between the two radiation electrodes inevitably increases, but a side ground electrode is provided in the dividing groove provided between the two radiation electrodes, and this side ground electrode is connected to the ground electrode having the ground potential. So
The spread of the electric field emitted from the radiation electrode is reduced at the side ground electrode, and the electric field coupling between adjacent radiation electrodes is weakened.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a first embodiment of an antenna device according to the present invention, and FIG. 2 shows an example of an embodiment of a single antenna.

In FIG. 1, the antenna substrate 1 has a right-angled quadrilateral shape, and a ground pattern (not shown) using a conductive material is formed on the entire front or back surface.
On the surface of the antenna substrate 1, two single antennas 2 and 3 are arranged in parallel and close to each other.

The single antennas 2 and 3 are, as shown in FIG.
It is configured using rectangular parallelepiped bases 4 and 5 using a dielectric material. On one main surface (surface) of the bases 4 and 5,
Strip-shaped radiation electrodes 6 and 7 are formed, and ground electrodes 10 and 11 are formed on the other main surfaces (back surfaces) of the bases 4 and 5 except for the periphery of the feed electrodes 8 and 9. I have. Furthermore, on the side surfaces extending in the longitudinal direction of the bases 4 and 5,
Side antennas 12 and 13 are provided, and the single antennas 2 and 3 are arranged with the side surfaces of the substrates 4 and 5 provided with the side antennas 12 and 13 facing each other.

The side ground electrodes 12 and 13 are electrically connected to the ground electrodes 10 and 11, and the ground electrodes 10 and 11 are electrically connected to the ground pattern of the antenna substrate 1 to form the side ground electrodes. Electrodes 12, 1
Set 3 to ground potential. Feeding electrodes 8 and 9 formed on the side surfaces of the bases 4 and 5 are respectively connected to individual feeding patterns (not shown) formed on the antenna substrate 1. The feed electrodes 8 and 9 are electrically coupled to the radiation electrodes 6 and 7 via the capacitance between the radiation electrodes 6 and 7.

In the above-described configuration, when transmission power is individually supplied from the feeding electrodes 8 and 9 to the radiation electrodes 6 and 7 of each of the single antennas 2 and 3, the single antennas 2 and 3 are set to a predetermined resonance frequency. And emit electromagnetic waves into space. At this time, the electric field directed to the adjacent single antennas 2 and 3 is formed between the side ground electrodes 12 and 13, and the electric field coupled to the radiation electrodes 6 and 7 of the adjacent single antennas 2 and 3 is weakened. . In other words, the divergence of the electric field (expansion of the electric field) on the side surfaces of the bases 4 and 5 where the side surface ground electrode is not provided.
However, the electric field strength coupling between the single antennas 2 and 3 becomes weaker on the side surfaces of the bases 4 and 5 provided with the side surface ground electrodes 12 and 13.

Therefore, the single antennas 2 and 3 can be arranged close to each other without excessively increasing the relative permittivity of the bases 4 and 5 of the single antennas 2 and 3, and the antenna device can be downsized accordingly. Can be configured. Further, since the width of the bases 4 and 5 can be reduced in accordance with the width of the radiation electrodes 6 and 7, the distance between the two single antennas 2 and 3 can be increased if the dimensions of the antenna substrate 1 are the same. As a result, the electric field coupling between the two single antennas 2 and 3 can be further reduced.

In the above-described embodiment, the side surface ground electrode 1 is provided on the opposing side surfaces of the two single antennas 2 and 3.
Although the power supply electrodes 8 and 9 are provided, another side surface ground electrode may be provided at a predetermined distance from the power supply electrodes 8 and 9 on the side surface of the base body on which the power supply electrodes 8 and 9 are provided. Further, the side surface ground electrode may be provided only on the side surface of one of the bases 4 and 5 of the single antennas 2 and 3. Further, in the single antennas 2 and 3 described above, the side ground electrodes 12 and 13 are provided on a part of the side surfaces of the bases 4 and 5. May be provided on the entire surface. The size of the side ground electrodes 12 and 13 is determined by the degree of electric field coupling between the single antennas 2 and 3 and the antenna characteristics of each single antenna 2 and 3.

Although the single antennas 2 and 3 are shown as single antennas having the same size, that is, as single antennas using substantially the same frequency band, the relative permittivity of the bases 4 and 5 may be changed. Alternatively, the dimensions of the radiation electrodes 6 and 7 may be changed to form single antennas having different frequencies. When a dielectric material having the same relative dielectric constant is used as the base of the single antennas 2 and 3, the dimensions of the bases and the dimensions of the radiation electrodes 6 and 7 are changed. The dimensions may be changed to form a single antenna having a different frequency.
With such a configuration, each of the single antennas 2 and 3 can be used as a different single antenna of the communication system.

Furthermore, in the above-described embodiment, two single antennas 2 and 3 are arranged on the antenna substrate 1. However, a plurality of single antennas 2 and 3 can be arranged depending on the application. Also in this case, a side surface ground electrode is provided on the side surface of the base of the adjacent single antenna. As a result, the electric field coupling between the single antennas can be weakened and the characteristics of each single antenna can be secured. Further, the antenna substrate 1 can be provided with a signal circuit for processing a transmission / reception signal using a margin.

Further, each of the above-mentioned single antennas 2 and 3 has:
A configuration in which transmission and reception are switched and used as different antennas of the communication system may be used. For example, a configuration in which the single antenna 1 is used as a single antenna dedicated to transmission and the single antenna 2 is used as a single antenna dedicated to reception. Is also good. Further, each of the single antennas 2 and 3 can be configured as a multiple resonance single antenna in order to widen the frequency bandwidth.

A second embodiment of the antenna device according to the present invention will be described with reference to FIG. FIG. 4 shows an embodiment of a single antenna used in the second embodiment. The same components as those of the first embodiment are denoted by the same reference numerals, and the description of the common components will not be repeated.

In FIG. 3, two single antennas 14, 1
Reference numeral 5 denotes a diagonally opposite position of the antenna substrate 1. The allowable size of the antenna substrate 1 is determined by the size of the housing of the wireless communication device to be mounted. For this reason, when a plurality of single antennas 14 and 15 are collectively arranged on the antenna substrate 1, the single antennas 14 and 15 are installed by making the most of the limited substrate area. Since the diagonal position is the farthest in the rectangular quadrangular antenna substrate 1, the distance between the single antennas 14 and 15 is increased as much as possible by disposing the single antennas 14 and 15 at the diagonal corners. Can be

In this case, the bases 4 and 5 of the single antennas 14 and 15 are provided with side ground electrodes on the side surfaces of the bases 14 and 15 facing the single antenna 14 or 15 on the other side. In the embodiment of FIG. 3, rectangular parallelepiped bases 4 and 5 are used, and opposing side surfaces of the single antennas 14 and 15 are, as shown in FIG. 4, long side surfaces 4a and 5a and short side surfaces 4b and 5b.
5b, the long side ground electrodes 16 and 17 and the short side ground electrodes 18 and 19 are provided on these side surfaces, respectively.

The longitudinal side ground electrodes 16 and 17
Are provided in the longitudinal sides 4a, 5a of the bases 4, 5 so as to be deviated in the direction of the opposing single antenna, but may be provided over the entire length of the bases 4, 5 in the longitudinal direction. Also,
When the bases 4 and 5 of the single antennas 14 and 15 are long and even if the single antennas 14 and 15 are arranged apart from each other in the diagonal direction of the antenna substrate 1, the parallel portions of the long side surfaces 4a and 5a of the bases 4 and 5 are large. , The longitudinal side ground electrodes 16 and 17 can be provided only on the longitudinal side surfaces 4a and 5a.

According to the antenna device described above, in addition to the effect of reducing the electric field coupling between the two single antennas 14 and 15 due to the provision of the side ground electrode, the single antenna 1
Since the distance between the single antenna 1 and the single antenna 15 is larger than that in the first embodiment of FIG.
The electric field coupling between the single antennas 14 and 15 can be weakened, in other words, the isolation between the single antennas 14 and 15 can be improved. Due to this synergistic effect, the single antennas 14, 1
5, the electric field coupling between them becomes smaller, and the single antenna 1
4 and 15 are close to the characteristics of a single antenna.

Further, since the installation intervals of the single antennas 14 and 15 can be increased, mutual interference between the single antennas 14 and 15 becomes smaller, and the directional characteristics of electromagnetic waves radiated from the radiation electrodes 6 and 7 into the space are reduced. The directivity characteristics of the antennas 14 and 15 are approximated.

A third embodiment of the antenna device according to the present invention will be described with reference to FIG. The same components as those of the first embodiment are denoted by the same reference numerals, and the description of the common components will not be repeated.

In FIG. 5, a GPS antenna 20 and an ETC antenna 21 are provided on the surface of the antenna substrate 1.
Are installed in close proximity. Since the center frequency of the GPS antenna 20 is 1.575 GHz and the center frequency of the ETC antenna 21 is 5.8 GHz, the volume of the base is smaller than that of the GPS antenna 20.
Can be made smaller. Here, each antenna 2
The effective line length L of the radiation electrodes 24 and 25 of 0 and 21 is determined by L = λ / 2√ε, where ε is the effective relative dielectric constant of the bases 22 and 23 and λ is the wavelength of the resonance frequency.

That is, the bases 22 and 23 of the GPS antenna 20 and the ETC antenna 21 are made of a ceramic material having the same relative dielectric constant, and the radiation electrode 25 of the ETC antenna 21 is smaller than the radiation electrode 24 of the GPS antenna 20. The main surface of the base 23 on which the radiation electrode 25 is formed is smaller than the main surface of the base 22 on which the radiation electrode 24 is formed. Further, the thickness of the base 23 is configured to be thinner than the thickness of the base 22. In addition,
The configurations of the power supply electrode and the ground electrode are the same as in the first embodiment of FIG.

The feature of the third embodiment is that G
Bases 22 and 2 of PS antenna 20 and ETC antenna 21
3, the antenna having the lower resonance frequency for exciting the radiation electrodes 24 and 25, that is, the side ground electrode 1 is provided on the opposite side 22a of the base 22 of the GPS antenna 20.
2 is provided, and no side surface ground electrode is provided on the opposing side surface 23 a of the base 23 of the ETC antenna 21.

As described above, when an antenna device is configured by assembling antennas of communication systems using different frequencies, the electric field of the higher-order resonance component at the resonance frequency of the GPS antenna 20 which is a low frequency is an ETC. Antenna 2
1, but the side surface ground electrode 12 is provided on the side surface 22a of the base 22 of the GPS antenna 20.
The electric field of the higher-order resonance component heading in the direction of the ETC antenna 21 can be suppressed. On the other hand, the higher frequency ET
The resonance frequency of the C antenna 21 has almost no effect on the resonance frequency of the GPS antenna 20.

As described above, since the interference of the GPS antenna 20 with the ETC antenna 21 becomes small, the GPS
The antenna characteristics of the ETC antenna 21 can be prevented from deteriorating while maintaining the antenna characteristics of the antenna 20. That is, the GPS antenna 20 and the ETC antenna 2
1 can exhibit sufficient antenna characteristics in each communication system.

A fourth embodiment of the antenna device according to the present invention will be described with reference to FIG. The feature of this embodiment is that two single antennas are formed on one base without using the antenna substrate 1 shown in FIG.

In FIG. 6, strip-shaped radiation electrodes 27 and 28 are formed in parallel on the main surface of a rectangular parallelepiped base 26, as in the first embodiment of FIG. Radiation electrode 2
Between the radiation electrode 7 and the radiation electrode 28, a dividing groove 29 for dividing the main surface on which the radiation electrodes 27 and 28 are formed is provided. A side surface ground electrode 30 is formed on the bottom and side surfaces of the dividing groove 29, and the connection electrode 31 provided on the side surface of the base 26 is formed.
Is connected to a ground electrode (not shown) provided on the other main surface (back surface) of the base 26 via the. The power supply electrode 32
Are provided in the same configuration as the first embodiment of FIG. 1 using the side surface of the base 26 for each of the radiation electrodes 27 and 28.

In the antenna device having this configuration, the base 2
The thickness of the portion provided with the dividing groove 29 is
Since it is thinner than the portion provided with 28, and the side surface ground electrode 30 is provided in the dividing groove 29 to have a ground potential, the portions of the radiation electrodes 27 and 28 function as independent single antennas.

In the above configuration, the radiation electrodes 27, 2
When power is supplied to each of the power supply electrodes 8 through the respective power supply electrodes 32, transmission and reception of electromagnetic waves can be performed. Also in this case, the dividing groove 29
Since the side surface ground electrode 30 is provided inside, the electric field coupling the radiation electrodes 27 and 28 to each other can be reduced. That is, even if the antenna device is configured using one base 26, the portions provided with the respective radiation electrodes 27 and 28 can ensure the antenna characteristics as a single antenna.

The experimental results will be described with reference to Tables 1 and 2. FIG. 7 shows the configuration of the single antenna used in the experiment. FIG.
In the figure, 34 is a base, 35 is a radiation electrode, 36 and 38 are side ground electrodes, 37 is a ground electrode, and 39 is a feed electrode, and has the same configuration as the single antenna of FIG. The side ground electrodes 36 and 38 are provided on the opposite side surfaces of the base 34. That is, the side surface ground electrode 36 is provided on the lower half of the side surface of the base 34 and connected to the ground electrode 37, and the side surface ground electrode 38 is provided on both sides of the base 34 apart from the power supply electrode 39 and on the lower half of the side surface of the base 34. To the ground electrode 37.

Table 1 shows combinations of two single antenna arrangements for the purpose of obtaining experimental data of the antenna device.

[0046]

[Table 1]

In the experiment, two single antennas 40 and 41 having different dimensions but the same electrode configuration were prepared. The single antenna 40 shown in Table 1 is a GPS antenna,
5 GHz frequency power, or a single antenna 4
1 was configured as an antenna for ETC, and supplied power at a frequency of 5.8 GHz. And both single antennas 40,
41 were arranged on a substrate having a grounded ground pattern at an interval d of 19 mm.

Symbols A-1 to C-3 in Table 1 indicate the arrangement of the two single antennas 40 and 41.
As shown in the figure, the square indicates the base 34, the straight line parallel to the two opposite sides of the square indicates the position of the side ground electrodes 36 and 38, and the triangle indicates the position of the feed electrode 39.

Symbols A-1 to A-3 in Table 1 indicate that the power supply electrode 39 side of the single antenna 40 is arranged to face the single antenna 41, and B-1 to B-3 indicate the shapes of the single antenna 40. In this embodiment, the side surface of the base body without the side ground electrodes 36 and 38 is arranged facing the single antenna 41.
C-3 is a form in which the side surface of the base of the single antenna 40 provided with the side surface ground electrode 36 faces the single antenna 41.

Table 2 shows the measured isolation values obtained with the single antenna arrangement of Table 1.

[0051]

[Table 2]

Table 2 shows the isolation (dB) indicating the degree of electric field coupling between the two single antennas 40 and 41.
According to the measurement values of B-1 to B-3 in Table 2, when the side surface of the base of the single antenna 40 having a low frequency, on which the ground electrodes 36 and 38 are not provided, is directed to the single antenna 41 having a high frequency. Compared to the isolation (21.0 dB) in which the side ground electrodes 36, 38 are not provided at all, it can be understood that the side ground electrodes 36, 38 have almost no effect.

According to the values of C-1 to C-3, when the side surface of the base of the single antenna 40 on which only the side surface ground electrode 36 is provided is directed toward the single antenna 41, the single antenna 41
Regardless of the position of the side ground electrode and the position of the feed electrode, the isolation between the two single antennas 40 and 41 was the best. On the other hand, when the side surface of the base of the single antenna 40 on which the power supply electrode 39 is provided is directed toward the single antenna 41, the effect of the provision of the side ground electrode 38 is slightly reduced as indicated by A-1 to A-3. Lower. It is considered that this is because the electric field leaking from the feed electrode 39 of the single antenna 40 having a low frequency is coupled to the single antenna 41.

FIG. 9 shows the isolation characteristics when the single antennas 40 and 41 are arranged in the form of symbol C-3 in Table 1 and the distance d between the single antenna 40 and the single antenna 41 is changed. From this graph, it can be understood that the greater the distance d between the two single antennas, the better the isolation.

[0055]

According to the antenna device of the first aspect, of the plurality of single antennas arranged close to each other, at least one of the single antennas is provided with the side surface ground electrode at the ground potential on the side surface of the base opposite to the single antenna. The spread of the electric field in the direction of the single antenna can be suppressed, and the electric field coupling between the adjacent single antennas can be reduced. Therefore, it is possible to arrange a plurality of single antennas close to each other, and it is possible to reduce the size of the entire antenna device. Further, since it is not necessary to weaken the electric field coupling between adjacent single antennas by excessively increasing the relative permittivity of the base constituting the single antenna as in the related art, a sufficient frequency bandwidth in each single antenna is required. Can be secured.

According to the antenna device of the present invention, since a plurality of single antennas function as antennas in the same frequency band, transmission and reception are performed separately as a collective antenna for a plurality of communication systems in the same communication system. It can be used for various purposes such as a single antenna.

According to the antenna device of the third aspect, on a substrate having a limited size, the two single antennas are arranged at diagonal positions for maximally separating the single antennas, and the side ground is provided on the side of the base opposite to the single antenna. Since the electrodes are provided, the isolation between adjacent single antennas can be improved as much as possible. Thereby, the directivity characteristics of the electromagnetic wave radiated from each single antenna can be improved. Also, since the distance between the adjacent single antenna can be reduced while maintaining the isolation at a constant value, the board size can be reduced,
The antenna device can be designed to be more compact.

According to the antenna device of the fourth aspect, when a plurality of single antennas having different resonance frequencies are provided side by side, the side ground electrode is provided on the opposite side surface of the base of the single antenna having a low resonance frequency. Even when the single antennas are arranged close to each other, the mutual interference is weakened and the antenna characteristics of each single antenna are ensured, so that a plurality of single antennas can be integrated in a small area range.

According to the antenna device of the fifth aspect, even when two radiation electrodes are provided using one base, a dividing groove is provided between the two radiation electrodes, and the side ground is provided in the dividing groove. Since the electrodes are provided, the two radiation electrodes can function as independent single antennas. Since the antenna device having this configuration does not require a substrate on which a single antenna is arranged, the size of the antenna device can be further reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of an antenna device according to the present invention.

FIG. 2 shows an embodiment of a single antenna used in FIG. 1,
(A) is a front perspective view, (B) is a back perspective view.

FIG. 3 is a perspective view showing another embodiment of the antenna device according to the present invention.

FIG. 4 shows an embodiment of a single antenna used in FIG. 3,
(A) is a perspective view as seen from the front side, and (B) is a perspective view as seen from the back side.

FIG. 5 is a perspective view showing still another embodiment of the antenna device according to the present invention.

FIG. 6 is a perspective view showing still another embodiment of the antenna device according to the present invention.

7A and 7B show a configuration of a single antenna used in an experiment of the antenna device according to the present invention, wherein FIG. 7A is a front perspective view, and FIG. 7B is a rear perspective view.

FIG. 8 is an explanatory diagram of a graphic used in Table 1.

FIG. 9 is an isolation characteristic diagram when a distance between two single antennas is a variable in the antenna device of the present invention.

[Explanation of symbols]

 1 Antenna substrate 2, 3, 14, 15, 40, 41 Single antenna 4, 5, 22, 23, 26, 34 Base 6, 7, 24, 25, 27, 28, 35 Radiation electrode 8, 9, 32, 39 Feeding electrode 10, 11, 37 Ground electrode 12, 13, 30, 36, 38 Side ground electrode 16, 17 Long side ground electrode 18, 19 Short side ground electrode 20 GPS antenna 21 ETC antenna 29 Dividing groove 31 Connecting electrode

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Tsune Akiyama 2-26-10 Tenjin, Nagaokakyo-shi, Kyoto Stock Company Murata Manufacturing Co., Ltd. (72) Inventor Kazuya Kawabata 2-26-10 Tenjin, Nagaokakyo-city, Kyoto Stock F-term (reference) in Murata Manufacturing Co., Ltd. 5J021 AA09 AB06 HA03 HA05 HA07 JA03 JA07 5J045 AA21 AB05 DA09 EA07 HA03 NA01 5J046 AA02 AA04 AB13 PA07 UA02 UA03

Claims (5)

[Claims] A dielectric substrate having a power supply electrode;
A plurality of single antennas each having a radiation electrode provided on one main surface of the base and a ground electrode provided on the other main surface are arranged close to each other, and the base of at least one single antenna is opposed to the adjacent single antenna. An antenna device, comprising: a side surface ground electrode electrically connected to the ground electrode on a side surface that fits. 2. The antenna device according to claim 1, wherein the plurality of single antennas are excited at a resonance frequency in the same frequency band. 3. A rectangular substrate having a ground pattern, and two single antennas each having a radiation base and a feed electrode provided on a dielectric substrate, wherein the single antenna is provided at both ends of a diagonal line of the substrate. And a side surface ground electrode electrically connected to the ground pattern is provided on one or both bases of each of the single antennas on a side surface facing the base member. 4. A first single antenna having a radiation base and a feed electrode on a dielectric base and excited at a first resonance frequency, and a first single antenna having a radiation base and a feed electrode on a dielectric base.
A second single antenna that excites at a second resonance frequency higher than the resonance frequency. The first single antenna and the second single antenna are arranged close to each other. An antenna device comprising a side surface ground electrode provided on a side surface facing a single antenna. 5. A dielectric substrate having first and second power supply electrodes, a first radiation electrode electrically coupled to the first power supply electrode, and a second power supply electrode on one main surface of the substrate. A second radiating electrode electrically coupled to the first radiating electrode, a dividing groove is provided between the first radiating electrode and the second radiating electrode of the base, a side surface ground electrode is provided in the dividing groove, and the side surface is provided. An antenna device, wherein a ground electrode is electrically connected to a ground electrode provided on the other main surface of the base.