JP3237604B2 - Antenna device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an antenna device used for portable communication equipment and the like.

[0002]

2. Description of the Related Art Conventionally, a linear antenna such as a monopole antenna has been known as an antenna used for a communication device such as a mobile phone. This linear antenna is mounted outside the housing of the communication device, which hinders the miniaturization of the communication device and prevents external antennas from acting on the antenna, causing damage, deformation, and characteristic deterioration of the antenna. There is a risk of causing. In addition, in order to attach the linear antenna to the casing of the communication device, it is necessary to interpose a coaxial cable or a connector, which increases the number of components of the communication device, which is not preferable in terms of cost.

In order to solve such a problem, for example, some antenna devices have been proposed in Japanese Patent Application Laid-Open No. 7-221537. Hereinafter, three antenna devices among the antenna devices proposed in the publication will be described with reference to FIGS. 9 to 11, respectively. The antenna device 100 shown in FIG. 9 includes a dielectric substrate 101. In the dielectric substrate 101, a through hole 102 having a radiation conductor on an inner wall is formed in a long side direction thereof. Further, on one end surface of the dielectric substrate 101, a side conductor 103 spreading on one end surface is formed, and at the center of the other end surface, a feed conductor 104 is formed. The side conductor 103 and the feed conductor 104 are It is electrically connected by a radiation conductor formed on the inner wall of the through hole 102. Further, rectangular side conductors 105, 1 are provided on both sides of the power supply conductor 104.
06 is formed.

A radiation conductor 112 is formed on the upper surface of the dielectric substrate 111 of the antenna device 110 shown in FIG. On the lower surface of the dielectric substrate 111, a ground conductor 113 extending on one short side of the lower surface is formed. Further, the dielectric substrate 11
A power supply conductor 114 is formed from the center of the lower surface to the side surface of the dielectric substrate 111. The dielectric substrate 111 has a through-hole 115 having a conductor on the inner wall, and the conductor of the through-hole 115 electrically connects the radiation conductor 112 and the feed conductor 114.

A rectangular radiation conductor 122 is formed on one short side of the upper surface of a dielectric substrate 121 constituting the antenna device 120 shown in FIG. A power supply conductor 123 is formed from the other short side surface of the dielectric substrate 121 to the upper and lower ends, and the power supply conductor 123 and the radiation conductor 122 are connected by a microstrip line 124. . This dielectric substrate 12
1 has a ground conductor 1 extending over substantially the entire lower surface thereof.
The ground conductor 125 is insulated from the power supply conductor 123. Further, on both sides of the power supply conductor 123, a side conductor 126 connected to the ground conductor 125 is provided.
Are formed, and the side conductor 126 is
3 is insulated.

[0009] The antenna devices 100, 110, and 120 shown in FIGS.
For example, the power supply conductors 104, 114, and 1 are mounted on a circuit board built in the communication device main body, and are supplied from the communication device body.
Power is supplied to the antenna devices 100, 110, 120 via 23 and the antenna devices 100, 110, 12
From 0, electromagnetic waves are emitted into the air.

[0007]

The antenna device 100 shown in FIG. 9 has a monopole antenna structure. An antenna device having a monopole antenna structure exhibits its performance when the radiation conductor extends perpendicular to the ground conductor. If the dielectric substrate 101 of the antenna device 100
If the ground conductor is formed on the lower surface, the ground conductor is provided parallel to the extending direction of the radiation conductor (the extending direction of the through hole 102), and the performance of the antenna device 100 is not exhibited. . Therefore, in the antenna device 100 shown in FIG. 9, the ground conductor is not formed on the lower surface of the dielectric substrate 101 so that the performance is maximized. When the antenna device 100 is mounted on a circuit board, if a ground conductor is formed on the circuit board on which the antenna device 100 is mounted, the ground conductor may exist in parallel with the through hole 102 of the antenna device 100. And the performance of the antenna device 100 is not exhibited. Therefore, in order to maximize the performance of the antenna device 100, a ground conductor cannot be formed on a portion of the circuit board where the antenna device 100 is mounted. However, a circuit board used for a communication device is generally a high-frequency circuit board, and in order for the high-frequency circuit board to exhibit its performance, it is essential to secure a sufficiently wide ground conductor on the circuit board. Therefore, it is not realistic to mount the antenna device 100 on a circuit board used for a communication device.

The antenna device 100 is non-directional in a plane perpendicular to the direction in which the through hole 102 extends. Therefore, this antenna device 10
If 0 is used for a mobile phone, for example, it is expected that electromagnetic waves will be radiated from the antenna device toward the human body, and there is concern about the effect on the human body. Each of the antenna devices 110 and 120 shown in FIGS. 10 and 11 has a microstrip antenna structure, and ground conductors 113 and 125 are formed on the lower surfaces of the dielectric substrates 111 and 121, respectively.
For this reason, the antenna device 110 shown in FIGS.
120 is expected to have unidirectionality, and FIG.
When the antenna devices 110 and 120 shown in FIG. 11 are used for a mobile phone, it is expected that electromagnetic waves radiated from the antenna device toward the human body will be suppressed. However, the antenna device 110 shown in FIG.
In order to establish electrical continuity with the substrate 4, it is necessary to form a through hole in the dielectric substrate 111 and to make the inner wall of the through hole a conductor, resulting in a problem of high manufacturing cost. Also,
In the antenna device 120 shown in FIG. 11, since each conductor such as the radiation conductor 122 is formed on the outer surface of the dielectric substrate 121,
Although it is easy to manufacture, the radiation conductor 1 having a half wavelength of the resonance wavelength of the electromagnetic wave, which operates as a radiation element of the microstrip line antenna, is provided on the upper surface of the dielectric substrate 121.
In addition to 22, a microstrip line 124 having a length of ４ wavelength is also formed. Therefore, the radiation conductor 12
The total length of 2 and the microstrip line 124 is 3/4 wavelength, which is too large for an antenna built in a communication device.

To solve this problem, it is conceivable to reduce the size of the antenna device 120 shown in FIG. 11 by adjusting the dielectric constant of the dielectric substrate 121 constituting the antenna device 120 shown in FIG. Antenna device 120
There is a problem that when the size is reduced, the radiation efficiency is reduced and the band is narrowed. The present invention has been made in view of the above circumstances, and has as its object to provide an antenna device having directivity, a wide band, a small size, and low cost.

[0010]

According to the present invention, there is provided an antenna apparatus for achieving the above object. (1) A dielectric substrate surrounded by rectangular upper and lower surfaces and four side surfaces. (2) The dielectric substrate extends over the dielectric substrate lower surface. Ground conductor (3) Radiating conductor extending in a belt shape along at least three sides of the upper surface of the dielectric substrate and having both ends spaced apart from each other by a predetermined distance and in contact with a fourth side excluding the three sides. An excitation conductor formed at a position on the upper surface of the dielectric substrate between the radiation conductors and having one end in contact with the center of the fourth side; (5) a radiation side formed on a side surface contacting the fourth side; A pair of radiation-ground short-circuit conductors connected to each end of the conductor and the ground conductor, respectively. (6) The pair of radiation-side surfaces of the side surfaces in contact with the fourth side.
A power supply conductor formed between the ground short-circuit conductors and connected to the excitation conductor; and (7) a short circuit between the radiation conductor and a part of the excitation conductor on the upper surface of the dielectric substrate, and / or
And a short-circuit conductor that short-circuits a part of the radiation-ground short-circuit conductor and a part of the power supply conductor on a side surface that is in contact with the side.

In the antenna device of the present invention, a short-circuit conductor short-circuits a part of the radiation conductor and the excitation conductor and / or a part of the radiation-ground short-circuit conductor and a part of the feed conductor. Thus, in the antenna device of the present invention, two resonance frequencies at which the reflection loss has a minimum value appear close to each other (these two resonance frequencies will be described later in detail with reference to FIG. 6). Therefore, when the antenna device of the present invention is used, the frequency band in which electromagnetic waves are efficiently transmitted and received is a band in which frequencies near two resonance frequencies are continuously connected, which is a disadvantage of the conventional microstrip antenna. Band characteristics are improved,
Broadband is achieved.

Also, the antenna device of the present invention has a microstrip antenna structure in which a ground conductor is formed on the lower surface of a dielectric substrate, and a radiation conductor is formed on an upper surface of the dielectric substrate. The antenna device having this structure exhibits the performance as an antenna more efficiently as the range in which the ground conductor is formed is wider. Therefore, when the antenna device of the present invention is mounted on a circuit board such as a high-frequency circuit board that requires a ground conductor that spreads over a wide range, it is convenient to efficiently exhibit the performance of the antenna apparatus.
Further, the antenna device of the present invention has unidirectionality. For this reason, when the antenna device of the present invention is incorporated in, for example, a mobile phone, it is necessary to incorporate the antenna device so that the directionality of the antenna device is opposite to the human body when using the mobile phone. As a result, the radiation of electromagnetic waves toward the human body is suppressed.

When the length of the radiation conductor formed on the dielectric substrate is set to, for example, a quarter of the resonance wavelength of the electromagnetic wave, the length of the radiation conductor is shown in FIG. The length may be shorter than the length of the antenna device 120. Therefore, the size of the antenna device can be reduced, and the antenna device can be suitably used for an antenna device built in a portable communication device. Also,
In the antenna device of the present invention, the conductor is formed only on the outer surface of the dielectric substrate. That is, it is not necessary to form a through hole for forming a radiation conductor, for example, in the dielectric substrate, and the manufacturing cost can be reduced. Further, in order to mount the antenna device of the present invention on a circuit board, the ground conductor of the antenna device and the ground conductor of the circuit board, and the power supply conductor of the antenna device and the power supply line of the circuit board may be soldered. No coaxial cable or connector is required to mount the antenna device. Therefore, the antenna device can be mounted on the circuit board at low cost.

[0014]

Embodiments of the present invention will be described below. FIG. 1 is a perspective view showing the antenna device according to the first embodiment of the present invention. The antenna device 10 shown in FIG. 1 includes a dielectric substrate 11, and a ground conductor (not shown) that spreads in a planar shape is formed on the lower surface of the dielectric substrate 11. A U-shaped radiation conductor 16 is formed on the upper surface of the dielectric substrate 11. This U-shaped radiation conductor 1
Reference numeral 6 denotes three sides 1 excluding the side 12 on the upper surface of the dielectric substrate 11.
The radiating conductor 16 extends in a band along 3, 14, and 15, and ends 16a and 16b of the radiating conductor 16 are in contact with the side 12 with a predetermined interval therebetween. A rectangular excitation conductor 17 is formed at a position between the U-shaped radiation conductors 16, and one end of the rectangular excitation conductor 17 is connected to the side 1.
2 is in contact with the center. A pair of radiation-ground short-circuit conductors 1 is provided on a side surface of the dielectric substrate 11 which is in contact with the side 12.
8 are formed. The radiation-ground short-circuit conductors 18a and 18 constituting the pair of radiation-ground short-circuit conductors 18
b is each end 16a, 16b of the radiation conductor 16, respectively.
And a ground conductor formed on the lower surface of the dielectric substrate 11. A power supply conductor 19 connected to the excitation conductor 17 is formed between the pair of radiation-ground short-circuit conductors 18. In the antenna device 10, a short-circuit conductor 20 (a portion shown by hatching in the figure) is formed from the upper surface to the side surface of the dielectric substrate 11. This short-circuit conductor 2
Numeral 0 indicates that the radiation conductor 16 and a part of the excitation conductor 17 are short-circuited on the upper surface of the dielectric substrate 11, and the radiation-ground short-circuit conductor 18a and the power supply conductor 1 are disposed on the side surface of the dielectric substrate 11.
9 are short-circuited.

The antenna device 10 configured as described above
Is a short-circuit conductor 20, which short-circuits a part of the radiation conductor 16 and the excitation conductor 17, and a part of the radiation-ground short-circuit conductor 18a and a part of the power supply conductor 19. This allows
In the antenna device 10, two resonance frequencies at which the reflection loss has a minimum value appear close to each other, and the antenna device 1
0 makes it possible to broaden the frequency of the electromagnetic wave transmitted and received. The manner in which the frequency of the electromagnetic wave is broadened by the antenna device of the present invention will be described later with reference to FIG.

The antenna device 10 includes the dielectric substrate 1
Since the ground conductor is formed on the lower surface of one and the radiation conductor 16 is formed on the upper surface of the dielectric substrate 11, and has a microstrip antenna structure, the antenna device 10 has unidirectionality. Therefore, for example, when the antenna device 10 is built in a mobile phone, when the mobile phone is used,
By incorporating the antenna device 10 so that the directionality of the directivity of the antenna device 10 is opposite to that of the human body, radiation of electromagnetic waves toward the human body is suppressed.

When the length of the radiation conductor 16 of the antenna device 10 is set to, for example, a quarter of the resonance wavelength of the electromagnetic wave, the length of the radiation conductor 16 becomes equal to the length of the antenna shown in FIG. The antenna device can be shorter than the length of the device, and the antenna device can be downsized. In addition, the antenna device 10
Since the conductor is formed only on the outer surface of the dielectric substrate 11, the manufacturing cost can be reduced. Further, in order to mount the antenna device 10 on a circuit board, the ground conductor of the antenna device 10 and the ground conductor of the circuit board, and the power supply conductor 19 of the antenna device 10 and the power supply line of the circuit board may be soldered. The antenna device 10 can be mounted on a circuit board at low cost.

The short-circuit conductor 20 of the antenna device 10 shown in FIG.
And a radiation-ground short-circuit conductor 18a and a feed conductor 19
Are short-circuited, but this short-circuit conductor 20 is
The radiation conductor 16 and the excitation conductor 17 may be short-circuited only partially, or the radiation-ground short-circuit conductor 18 may be used.
And only a part of the power supply conductor 19 may be short-circuited. Hereinafter, as a modified example of the antenna device shown in FIG. 1, an antenna device having a short-circuit conductor different from the short-circuit conductor 20 of the antenna device shown in FIG. 1 will be described.

FIGS. 2A to 2F are perspective views showing the antenna devices. In the description of each antenna device shown in FIGS. 2A to 2F, the same components as those of the antenna device shown in FIG. 1 are denoted by the same reference numerals, and shown in FIG. Only differences from the antenna device will be described. The short-circuit conductor of each antenna device is shown by hatching in the figure.

A short-circuit conductor 32 for short-circuiting a part of the radiation conductor 16 and the excitation conductor 17 is formed on the dielectric substrate 11 of the antenna device 31 shown in FIG. FIG. 2 (b)
A short-circuit conductor 34 for short-circuiting a part of the radiation-ground short-circuit conductor 18a and a part of the feed conductor 19 is formed on the dielectric substrate 11 of the antenna device 33.

The dielectric substrate 11 of the antenna device 35 shown in FIG. 2C has a short-circuit conductor 36 for short-circuiting a part of the radiation conductor 16 and the excitation conductor 17 and a short-circuit conductor for radiation-ground 1
8a and short-circuit conductor 3 for short-circuiting a part of feed conductor 19
7 are formed. On the dielectric substrate 11 of the antenna device 38 of FIG. 2D, two short-circuit conductors 39 for short-circuiting a part of the radiation conductor 16 and a part of the excitation conductor 17 are formed.

In the dielectric substrate 11 of the antenna device 40 shown in FIG. 2E, the radiation-ground short-circuit conductor 18a and the short-circuit conductor 41 for short-circuiting a part of the power supply conductor 19, the radiation-ground short-circuit conductor 18b and the power supply. A short-circuit conductor 42 for short-circuiting a part of the conductor 19 is formed. A short-circuit conductor 44 that short-circuits a part of the radiation conductor 16 and the excitation conductor 17 is provided on the dielectric substrate 11 of the antenna device 43 of FIG.
A short-circuit conductor 45 that short-circuits the radiation-ground short-circuit conductor 18a and a part of the feed conductor 19 is formed. Also,
The radiation conductor 16 extends from the upper surface to the side surface of the dielectric substrate 11.
A short-circuit conductor 46 that short-circuits a part of the excitation conductor 17 and a part of the radiation-ground short-circuit conductor 18b and a part of the feed conductor 19 is formed.

As described above, the short-circuit conductor formed on the dielectric substrate 11 may be a part of the radiation conductor 16 and the excitation conductor 17 and / or a pair of the radiation-ground short-circuit conductor 1.
What is necessary is just to short-circuit 8 and a part of the power supply conductor 19. FIG. 3 is a perspective view illustrating an antenna device according to a second embodiment of the present invention. The antenna device 70 shown in FIG. 3 includes a dielectric substrate 71, and a ground conductor (not shown) that spreads in a planar shape is formed on the lower surface of the dielectric substrate 71. A radiation conductor 76 is formed on the upper surface of the dielectric substrate 71. The radiation conductor 76 has sides 72, 73, 7
4 and 75, the ends 76a and 76b of the radiation conductor 76 are separated from each other by a predetermined distance between the sides 7a and 76b.
It touches 2. An excitation conductor 77 is formed at a position between the radiation conductors 76, and the excitation conductor 77 has two rectangular portions 77a and 77b.
One of the rectangular portions 77a and 77b
a is formed so as to extend inside the radiation conductor 76, and the other rectangular portion 77 b is formed with ends 76 a,
76b. This one rectangular portion 77a
Is a width W larger than the width W2 of the other rectangular portion 77b.
The end of the excitation conductor 77 on the side of the rectangular portion 77 b is in contact with the center of the side 72. A pair of radiation-ground short-circuit conductors 78 are formed on the side surface of the dielectric substrate 71 that is in contact with the side 72. The radiation-ground short-circuit conductors 78a and 78b that constitute the pair of radiation-ground short-circuit conductors 78 are each an end portion 7 of the radiation conductor 76.
6a and 76b and a ground conductor formed on the lower surface of the dielectric substrate 71. A power supply conductor 79 connected to the rectangular portion 77b of the excitation conductor 77 is formed between the pair of radiation-ground short-circuit conductors 78. Further, this antenna device 70 has a short-circuit conductor 8
0, 81 (portions indicated by hatching in the figure) are formed. Of the short-circuit conductors 80 and 81, the short-circuit conductor 80
, Short-circuits the end 76a of the radiation conductor 76 and the rectangular portion 77b of the excitation conductor 77, and the other short-circuit conductor 81 short-circuits the end 76b of the radiation conductor 76 and the rectangular portion 77b of the excitation conductor 77.

As described above, the excitation conductors may have different widths.

[0025]

Embodiments of the present invention will be described below. As an example, an antenna device 33 shown in FIG.
As a comparative example, an antenna device having no short-circuit conductor was used. Hereinafter, an antenna device of a comparative example will be described.

FIG. 4 is a perspective view showing the antenna device of this comparative example. In describing the antenna device 50 shown in FIG. 4, the same components as those of the antenna device 10 shown in FIG. 1 are denoted by the same reference numerals, and only the differences from the antenna device 10 shown in FIG. Will be described.
The difference between the antenna device 50 shown in FIG. 4 and the antenna device 10 shown in FIG. 1 is that the antenna device 50 shown in FIG.
However, the only difference is that the short-circuit conductor 20 included in the antenna device 10 shown in FIG. 1 is not provided.

Next, a method of manufacturing the antenna devices of the embodiment and the comparative example will be described. In manufacturing the antenna devices of the example and the comparative example, first, the dielectric substrate 11 was manufactured.
Material was selected. The material of the dielectric substrate 11 has a stable relative dielectric constant (ε _r ) in a high frequency band, a low loss,
It is preferable that the temperature coefficient (τ _f ) of the resonance frequency is small. Here, alumina-based ceramics (ε _r = 8.5 at 2 GHz, Q = 1000, τ _f = 38 ppm /
° C). The dielectric substrates 11 of the antenna devices 33 and 50 of the example and the comparative example were manufactured using this material. The length x width x thickness of the dielectric substrate 11 is 16 mm x 1
4 mm × 4 mm. The manufactured dielectric substrate 11
Next, the pattern of each conductor was changed to a silver-platinum paste (Dupo).
n company QS-171) by screen printing method,
It was fired at 850 ° C. Thus, the antenna devices 33 and 50 of the example and the comparative example were manufactured.

In this case, a silver-platinum paste is used to print the pattern of each conductor.
The conductor pattern may be printed using a paste of gold, nickel, or the like. Further, here, each conductor is formed on the dielectric substrate 11 by printing a silver-platinum paste, but each conductor may be formed on the dielectric substrate 11 by vapor deposition, foil attachment, or the like. .

The antenna devices 33 and 50 of the example and the comparative example manufactured as described above were mounted at the center of a copper plate of 100 mm square. FIGS. 5A and 5B are a top view and a side view, respectively, showing the antenna device of the embodiment mounted on a copper plate.
It is. In mounting the antenna device 33 of this embodiment on the copper plate 61, a through hole was formed in the center of the copper plate 61, and the SMA connector 62 was soldered to the through hole. The SMA connector 62 is soldered so that its center conductor projects from the surface of the copper plate 61. This S
After soldering the MA connector 62, its central conductor,
By soldering the power supply conductor 19 of the antenna device 33, the antenna device 33 was mounted on the copper plate 61 as shown in FIG. Also, the antenna device 50 of the comparative example was mounted on a copper plate in the same manner as the mounting method of the antenna device 33 of the example.

Next, the reflection loss of each of the antenna devices 33 and 50 of the embodiment and the comparative example mounted on the copper plate was measured. Hereinafter, the measurement results will be described. FIG.
FIG. 7 is a diagram illustrating frequency characteristics of reflection loss of the antenna device of the example, and FIG. 7 is a diagram illustrating frequency characteristics of reflection loss of the antenna device of the comparative example. As shown in FIG. 7, the antenna device 50 of the comparative example having no short-circuit conductor has the following features.
839 GHz is the resonance frequency. At this time, the frequency band in which the reflection loss is −10 dB or less is 1.83.
The frequency band is from 41 GHz to 1.847 GHz, the frequency bandwidth is 16 MHz, and the fractional bandwidth is 0.87%. On the other hand, as shown in FIG. 6, in the antenna device 33 of the embodiment having the short-circuit conductor, resonance occurs at 1.956 GHz and a main peak is observed at 1.956 GHz. Inflated. This is 1.99
This is because they also resonate at GHz, and due to the resonance at different frequencies from 1.942 GHz to 1.99 GHz.
The reflection loss is -10 dB or less continuously up to 9 GHz. At this time, the frequency bandwidth where the reflection loss is −10 dB or less is 57 MHz, the center frequency is 1.971 GHz,
The bandwidth ratio is 2.89%. Therefore, comparing the antenna device 33 of the embodiment with the antenna device 50 of the comparative example,
It can be seen that there is an effect of expanding the fractional band three times or more.

FIG. 8 is a diagram showing a radiation pattern of the antenna device of the embodiment mounted on a copper plate as shown in FIG. FIG. 8 shows a radiation pattern in the XZ plane shown in FIG. 5B. The X axis and Z axis shown in FIG. 8 correspond to the X axis and Z axis shown in FIG. 5, respectively. Antenna device 3
The direction in which the gain of the electromagnetic wave radiated from 3 is maximized is in the D-axis direction (this D
The axis corresponds to the D axis shown in FIG.
The gain is as high as 0 dB. Also, the Z-axis direction is about -1
dB axis, but in the W axis direction opposite to the Z axis direction (this W axis corresponds to the W axis shown in FIG. 5B)
Is -16 dB, and when the Z-axis direction and the W-axis direction are compared, the gain has a difference of 15 dB or more, and it can be seen that the antenna device of the example has a clear directivity.

[0032]

As described above, according to the antenna device of the present invention, it is possible to achieve directivity, wide band, small size, and low cost.

[Brief description of the drawings]

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

FIG. 2 is a perspective view showing each antenna device on which a short-circuit conductor different from the short-circuit conductor 20 of the antenna device shown in FIG. 1 is formed.

FIG. 3 is a perspective view illustrating an antenna device according to a second embodiment of the present invention.

FIG. 4 is a perspective view showing an antenna device of a comparative example.

FIG. 5 is a diagram showing the antenna device of the embodiment mounted on a copper plate.

FIG. 6 is a diagram illustrating frequency characteristics of reflection loss of the antenna device according to the embodiment.

FIG. 7 is a diagram illustrating frequency characteristics of reflection loss of the antenna device of the comparative example.

FIG. 8 is a diagram showing a radiation pattern of the antenna device according to the embodiment mounted as shown in FIG. 5;

FIG. 9 is a perspective view showing an antenna device proposed in Japanese Patent Application Laid-Open No. 7-221537.

FIG. 10 is a perspective view showing another antenna device proposed in Japanese Unexamined Patent Application Publication No. 7-221537, which is different from FIG.

FIG. 11 is different from FIG. 9 and FIG.
It is a perspective view which shows the antenna device proposed in No. 37 publication.

[Explanation of symbols]

10, 31, 33, 35, 38, 40, 43, 50, 7
0 Antenna device 11, 71 Dielectric substrate 12, 13, 14, 15, 72, 73, 74, 75 Side 16, 76 Radiation conductor 16a, 16b, 76a, 76b End 17, 77 Excitation conductor 18, 78 A pair of radiation -Ground short-circuit conductors 18a, 18b, 78a, 78b Radiation-Ground short-circuit conductors 19, 79 Feed conductors 20, 32, 34, 36, 37 39, 41, 42, 4
4, 45, 46, 80, 81 Short-circuit conductor 61 Copper plate 62 SMA connector 77a, 77b Rectangular part

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-9-219619 (JP, A) JP-A-9-214240 (JP, A) JP-A-10-13139 (JP, A) JP-A-9-209 153734 (JP, A) JP-A-7-221537 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01Q 13/08 H01Q 1/27 H01Q 1/38 H01Q 5/01 JICST File (JOIS)

Claims (1)

(57) [Claims] 1. A dielectric substrate surrounded by a rectangular upper and lower surface and four side surfaces, a ground conductor extending on the lower surface of the dielectric substrate, and a band extending along at least three sides of the upper surface of the dielectric substrate. A radiation conductor contacting a fourth side excluding the three sides with a predetermined interval between each other; and a portion formed on the upper surface of the dielectric substrate at a position inserted between the radiation conductors, one end of which is A pair of radiation-ground short-circuit conductors formed on the side surface contacting the fourth side and connected to each end of the radiation conductor and the ground conductor, respectively; A power supply conductor formed between the pair of radiation-ground short-circuit conductors and connected to the excitation conductor on a side surface in contact with the fourth side; and a radiation conductor and the excitation conductor on an upper surface of the dielectric substrate. Short-circuit some parts, and And / or an antenna device comprising: the radiation-ground short-circuit conductor and a short-circuit conductor that short-circuits a part of the feed conductor on a side surface in contact with the fourth side.