JP2003283238A - Antenna device, communication device and method for designing the antenna device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the height of an antenna device for a reduction in thickness of the antenna, in a folding cellular phone of PDC (personal digital cellular) type using, e.g. an 800 MHz band for communication. <P>SOLUTION: The antenna device comprises an antenna element 110 with a feeding plate 111, a grounding plate 120 placed opposite to the antenna element 110, a short-circuit plate 130 connecting the antenna element 110 to the grounding plate 120, and a single or a plurality of grounding lines 140 having (1) a linear shape, or (2) having a bending or a curving shape and being connected to a predetermined position on the grounding board 120. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna device, a communication device, and an antenna device design method used in, for example, a mobile phone.

[0002]

2. Description of the Related Art First, referring to FIG. 13 which is a perspective view of a conventional inverted F antenna and FIG. 14 which is a plan view of a conventional inverted F antenna, a conventional inverted F antenna (for example, see Patent Document 1). Reference) will be described.

A conventional inverted F antenna includes an antenna element 110 having a feeding plate 111 for feeding from a feeding point 112, a base plate 120 arranged so as to face the antenna element 110, an antenna element 110 and the base plate 120. And a short-circuit plate 130 to be connected.

The main plate 120 has a long side length (length) of 16
It has a substantially rectangular plate shape having a length of 5 mm and a short side length (width) of 44 mm (see FIG. 14).

The length of the main plate 120 is 165 mm.
Is almost equal to the total length when the folding type mobile phone is opened, and is a numerical value corresponding to λ / 2, which is half the wavelength λ in the 900 MHz band. In addition, H = 4, which is the distance between the antenna element 110 and the ground plane 120.
mm (see FIG. 13) is an example of a numerical value required as the height of the antenna to be incorporated in a folding type mobile phone whose tendency to be thin is remarkable.

Such a conventional inverted F antenna is a Smith chart for explaining the characteristics of the input impedance in which the antenna is viewed from the feeding point of the conventional inverted F antenna (d = 13 mm), as shown in FIG. 15 (a). And the same VSWR
(Voltage standing wave ratio, Voltage Standing
The impedance characteristic is as shown in FIG. 15B which is an explanatory view of the Wave Ratio.

[0007]

[Patent Document 1] Japanese Patent No. 1685741

[0008]

However, the above-mentioned conventional inverted F antenna does not have a frequency range of VSWR ≦ 2 at all (see FIG. 15B), so-called 50Ω.
Since it did not match, it was extremely unsuitable for practical use.

Of course, by reducing the distance d between the feeding plate 111 and the short-circuiting plate 130, Smith for explaining the characteristics of the input impedance in which the antenna is taken into consideration from the feeding point of the conventional inverted F antenna (d = 2 mm). FIG. 16 (a), which is a chart, and VSWR (voltage standing wave ratio).
It is possible to realize the impedance characteristic as shown in FIG. However,
When d = 2mm, the resonance frequency is 839MHz
And the frequency range of VSWR ≦ 2 is 799 to 87.
Although it is 2 MHz, the bandwidth is only 73 MHz. Therefore, the fractional bandwidth obtained by dividing the bandwidth by the center frequency is only 8.7%. Therefore, for example, a PDC (Personal Digi) using the 800 MHz band for communication is used.
Even if such an inverted F antenna is built into a communication device of the tal cellular system, a 17% or more specific bandwidth required for communication by this system is not achieved, and full coverage of transmission and reception is difficult.

In view of the above conventional problems, it is an object of the present invention to provide an antenna device, a communication device, and an antenna device designing method, which can realize, for example, thinning of a folding type mobile phone. Is.

[0011]

A first aspect of the present invention includes an antenna element (110) having a feeding portion (111),
A base plate (120) arranged to face the antenna element (110), and the antenna element (11).
0) and the ground plane (120) are connected to each other by a short-circuit portion (13
0) and a predetermined position of the main plate (120),
An antenna device having (1) a straight line shape, or (2) a single or a plurality of ground wires (140) having a shape having a bend or a curve.

The second aspect of the present invention comprises an antenna element (110) having a feeding portion (111) and a substantially rectangular plate shape having a short side and a long side, which is arranged so as to face the antenna element (110). The ground plane (120) has, a short-circuit part (130) connecting the antenna element (110) and the ground plane (120), and a single or a plurality having a predetermined shape connected to a predetermined position of the ground plane (120). A ground wire (150), the antenna element (110) is disposed on the short side, and the ground wire (15) is provided.
All or part of 0) is connected to the corner of the main plate (120) on the side of the antenna element (110), and is formed outside the short side on the side of the antenna element (110) having a width of the short side or less. Is an antenna device having a substantially spiral shape.

A third aspect of the present invention is an antenna element (110 ') having a feeding portion (111'), and a substantially rectangular shape having a short side and a long side arranged facing the antenna element (110 '). Base plate (120 ') having a plate shape
A short circuit part (130 ') connecting the antenna element (110') and the ground plate (120 '), and a single or plural grounds having a predetermined shape connected to a predetermined position of the ground plate (120'). A line (160), the antenna element (110 ′) is arranged on the short side, and all or part of the ground line (160) is along a long side of the ground plate (120 ′). In the antenna device, the legs are connected in the middle of the long side and are formed on the outside of the short side on the antenna element (110 ') side having a width equal to or smaller than the short side and having a substantially spiral shape.

In a fourth aspect of the present invention, the ground wire (170) is
At least a part thereof is the antenna device according to the first aspect of the present invention, which is located in a plane different from that of the ground plane (120 ').

A fifth aspect of the present invention is an antenna device for use in a mobile phone, wherein the antenna device is located in a plane different from that of the main plate (120 '). Is the antenna device of the fourth aspect of the present invention, which is located on the side farther from the user's head when used.

In a sixth aspect of the present invention, the ground wire (140) is
It is the antenna device according to the first aspect of the present invention that is commonly used as a ground electrode.

In a seventh aspect of the present invention, the antenna device is an antenna device for use in a mobile phone having a camera (200) and / or a receiver, and the ground electrode is the camera (200) and / or the ground electrode. Alternatively, it is the antenna device of the sixth aspect of the present invention, which is the ground electrode of the receiver.

In an eighth aspect of the present invention, the ground wire (140) is
The antenna device according to the first aspect of the present invention is configured as a member different from the base plate (120).

The ninth aspect of the present invention is that the antenna device is an antenna device for use in a mobile phone having a housing, and is constructed as a member different from the main plate (120). It is an antenna device according to an eighth aspect of the present invention, which is configured as a member to be attached to the inner wall portion of the body.

The tenth aspect of the present invention provides the ground wire (140).
Has at least part of the antenna element (1
The antenna device according to the first aspect of the present invention does not face (10).

The eleventh aspect of the present invention provides the short-circuit portion (13
0 ′, 130 ″) has a plurality of short-circuit pins (130 ′, 130 ″) respectively corresponding to predetermined use frequencies, and the short-circuit pin to be used among the plurality of short-circuit pins (130 ′, 130 ″). The antenna device according to the first aspect of the present invention further includes a switch circuit (300) for switching to (130 ′, 130 ″).

The twelfth aspect of the present invention is the antenna device according to the first aspect of the present invention, wherein the antenna element (110) has a predetermined slit (S).

The thirteenth aspect of the present invention provides the ground wire (140 ').
Is the antenna device of the first present invention having a coil (L1) and / or a capacitor (C1) in a part thereof.

In the fourteenth aspect of the present invention, the coil (L1) and / or the capacitor (C1) are connected to the ground wire (1).
40 ') is an antenna device of the thirteenth invention used for equivalently adjusting the electrical length.

The fifteenth aspect of the present invention provides the ground wire (170, 1).
80) are provided in plural, and each line (170,
180) is an antenna device according to the first aspect of the present invention, each of which corresponds to a predetermined operating frequency.

The 16th aspect of the present invention provides the ground wire (150 ').
Is an antenna device of the fourth present invention having a helical shape.

A seventeenth aspect of the present invention is directed to the antenna device (1) of the first aspect of the present invention, transmitting means (2) for transmitting a radio wave signal using the antenna device (1), and the antenna device. A communication device comprising a receiving means (3) for receiving a radio wave signal by utilizing (1).

In the eighteenth aspect of the present invention, the antenna device is
An antenna device for use in a mobile phone, the first casing (2200) accommodating the antenna device and a second casing (2200) different from the first casing (2200).
100) and a hinge part (2300) that connects the first casing (2200) and the second casing (2100) to each other, is the communication device according to the seventeenth aspect of the present invention.

The nineteenth aspect of the present invention provides a predetermined antenna device, a first housing (4200) for housing the antenna device and a predetermined substrate (4220), and the first housing (4200). A second housing (4100) different from each other,
The first housing (4200) and the second housing (410
0) and a hinge part (4300) connected to each other, and the ground of the substrate (4220) and the hinge part (4300) are electrically connected communication devices.

In a twentieth aspect of the present invention, the electrical connection is
The communication device according to the 19th aspect of the present invention, wherein one end of both ends of the hinge portion (4300) is connected to the ground of the substrate (4220) and the other end is opened. Is.

The 21st invention of the present invention is an antenna device designing method for the antenna device of the 1st invention, wherein the predetermined position and / or the predetermined shape is adjusted based on a predetermined rule. .

The 22nd aspect of the present invention provides the ground wire (140 ').
Has a coil (L1) and / or a capacitor (C1) in a part thereof, in order to adjust the coil (L1) and / or the capacitor (C1) equivalently to the electric length of the ground wire. It is a method of designing an antenna device according to the 21st aspect of the present invention.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) First, the configuration of the inverted F antenna of the present embodiment will be described with reference mainly to FIG. 1 which is a perspective view of the inverted F antenna of the embodiment 1 of the present invention.

The inverted F antenna of this embodiment has a feeding point 1
12, an antenna element 110 having a power feeding plate 111 for feeding power, a base plate 120 arranged to face the antenna element 110, and an antenna element 11
A short-circuit plate 130 for electrically connecting 0 and the ground plane 120;
The ground wire 140 has a linear shape and is connected to a predetermined position A of the ground plate 120.

The antenna element 110 corresponds to the antenna element of the present invention, the feeding plate 111 corresponds to the feeding portion of the present invention, the ground plate 120 corresponds to the ground plate of the present invention, and the short-circuit plate 130 is the short circuit of the present invention. Corresponding to the section, the ground line 14
0 corresponds to the ground line of the present invention. The inverted F antenna of this embodiment corresponds to the antenna device of the present invention.

The height of the inverted F antenna of this embodiment (that is, the distance between the antenna element 110 and the ground plane 120) is as small as 4 mm, and it can be sufficiently incorporated in a thin folding type mobile phone.

Here, the configuration of the inverted F antenna of the present embodiment will be described in more detail with reference mainly to FIG. 2 which is a plan view of the inverted F antenna of the first embodiment of the present invention.

The base plate 120 is made of copper, which is a conductive material, and has a substantially rectangular plate shape having a long side length (length) of 165 mm and a short side length (width) of 44 mm. There is.
As described above, the length of the main plate 120 is 165.
mm is substantially the same as the total length when the folding type mobile phone is opened, and is a numerical value corresponding to λ / 2, which is half the wavelength λ in the 900 MHz band.

The antenna element 110 is made of copper, which is a conductive material, and has a length of 40 mm and a width of 44 m.
It has a substantially rectangular plate shape of m and is arranged on the short side of the main plate 120.

The feeding plate 111 is made of copper which is a conductive material, has a plate shape with a width of 1 mm, and is electrically connected to the antenna element 110.

The short-circuit plate 130 is made of copper which is a conductive material, has a plate shape with a width of 3 mm, and is electrically connected to the base plate 120 and the antenna element 110, respectively.

Here, the distance between the power supply plate 111 and the short-circuit plate 130 is 13 mm.

The ground wire 140 is made of copper, which is a conductive material, and has a linear shape with a length of 90 mm and a width of 2 mm.
Main plate 120 on which the antenna element 110 is arranged
Is connected to a predetermined position A of 38 mm from the short side.

As described above, the inverted F antenna of this embodiment is the above-mentioned conventional inverted F antenna (see FIGS. 13 to 14).
It has a configuration similar to that, but is characterized in that it has a straight ground line 140 connected to a predetermined position A of the main plate 120.

Next, it is a Smith chart for explaining the characteristics of the input impedance in which the antenna is viewed from the feeding point of the inverted F antenna according to the first embodiment of the present invention.
The operation of the inverted F antenna of the present embodiment will be described mainly with reference to (a) and FIG. 3B which is an explanatory diagram of the VSWR (voltage standing wave ratio).

When the inverse F antenna of the present embodiment is operated by feeding from the feeding point 112 and the frequency characteristic is measured, it is extremely good as shown in FIGS. 3 (a) and 3 (b). The frequency characteristics were obtained.

Specifically, in the inverted F antenna of this embodiment, the resonance frequency is 900 MHz and the VSWR at this time is 1.28. The frequency range where VSWR ≦ 2 is 829 to 987 MHz. Therefore, in the inverted F antenna of this embodiment, the bandwidth is 1
There is also 58 MHz, and the ratio band is 17.4%, which is twice as large as that in the conventional case (the ratio band required for communication by the PDC system was 17% or more as described above).

There is an inflection point in the Smith chart of the inverted F antenna of this embodiment (see FIG. 3A), which is the antenna element 110 (see FIG. 1) and the ground plane 12.
It means that multiple resonance exists between 0 (see FIG. 1). That is, the ground plane 140 is moved by the ground line 140.
That is, the phase and amplitude of a specific portion of are fixed, the electrical length of the ground plane 120 is changed, and the resonance frequency of the antenna element 110 and the resonance frequency of the ground plane 120 are close to each other, so that a wide band characteristic is realized.

In the present embodiment, the base plate 12
Since the dimension of 0 is too large to resonate at the desired frequency, the ground line 140 was utilized to equivalently shorten the electrical length of the ground plane 120. However, if the dimensions of the ground plane are too small to resonate at a desired frequency, the ground wire 14 is not limited to this.
The electrical length of the main plate 120 may be lengthened equivalently by using 0.

Of course, the above-mentioned dimensions in the present embodiment are merely examples, and the present invention is not limited to such dimensions (the same applies to the following embodiments).

(Embodiment 2) Next, the configuration of the inverted F antenna of the present embodiment will be described with reference mainly to FIG. 4 which is a perspective view of the inverted F antenna of the embodiment 2 of the present invention.

The inverted-F antenna of this embodiment is the feed plate 1
An antenna element 110 having 11; a base plate 120 arranged so as to face the antenna element 110; a short-circuit plate 130 electrically connecting the antenna element 110 and the base plate 120; and a predetermined position B of the base plate 120. The ground wire 150 having a substantially spiral shape having a bend.

The ground wire 150 corresponds to the ground wire of the present invention.

Now, the configuration of the inverted F antenna of the present embodiment will be described in more detail with reference mainly to FIG. 5 which is a plan view of the inverted F antenna of the second embodiment of the present invention.

The ground wire 150 is made of copper, which is a conductive material, is connected to a predetermined position B which is a corner of the ground plane 120 on the antenna element 110 side, and is on the antenna element 110 side of the width of the short side of the ground plane 120. Width of 2m formed so as not to face the antenna element 110 outside the short side of the
It has a substantially spiral shape of m.

As described above, the inverted F antenna of this embodiment has a structure similar to that of the inverted F antenna of the first embodiment described above (see FIGS. 1 and 2), but at a predetermined position of the main plate 120. It is characterized in that it has a ground wire 150 connected to B and having a substantially spiral shape with a bend.

Here, the substantially spiral shape having a bend in this embodiment will be described in more detail.

The ground line 150 has first to fifth bending points P1 to P5 which are bent at right angles. The bending points are numbered sequentially from the bending point near the tip of the ground wire 150 (thus, the bending point near the predetermined position B, which is the root of the ground wire 150, is the fifth bending point P5). .

The length from the tip of the ground wire 150 to the first bending point P1 is approximately 6 mm, and the first bending point P1
To the second bending point P2 is about 6 mm, and the length from the second bending point P2 to the third bending point P3 is about 40 mm and the third bending point P3. To the fourth bending point P4 is approximately 10 mm, and the length from the fourth bending point P4 to the fifth bending point P5 is approximately 44 mm, and the fifth bending point P5 is The length from the root to the root of the ground wire 160 is approximately 20 mm.

The portion from the tip of the ground wire 150 to the first bending point P1, the portion from the second bending point P2 to the third bending point P3, and the fourth bending point P4 to the fifth bending point P3. The portion up to the bending point P5 is substantially parallel to the short side of the main plate 120. The distance between the tip of the ground wire 150 and the first bending point P1 and the portion from the second bending point P2 to the third bending point P3 is approximately 2 mm. Further, the interval between the portion from the second bending point P2 to the third bending point P3 and the portion from the fourth bending point P4 to the fifth bending point P5 is approximately 2 mm.

Further, the portion from the first bending point P1 to the second bending point P2, the portion from the third bending point P3 to the fourth bending point P4, and the fifth bending point P5 to the ground line. The part up to the root of 160 is substantially parallel to the long side of the main plate 120. The interval between the first bending point P1 to the second bending point P2 and the third bending point P3 to the fourth bending point P4 is approximately 36 mm. In addition, the distance between the third bending point P3 to the fourth bending point P4 and the fifth bending point P5 to the root of the ground line 160 is
It is approximately 40 mm.

Next, FIG. 6 is a Smith chart for explaining the characteristics of the input impedance in which the antenna is viewed from the feeding point of the inverted F antenna according to the second embodiment of the present invention.
The operation of the inverted F antenna of the present embodiment will be described mainly with reference to (a) and FIG. 6B which is an explanatory diagram of the VSWR (voltage standing wave ratio).

When the inverse F antenna of the present embodiment is operated by feeding power from the feeding point 112 and the frequency characteristic is measured, as shown in FIGS. 6 (a) and 6 (b), it is extremely good. The frequency characteristics were obtained.

Specifically, in the inverted F antenna of this embodiment, the frequency range where VSWR ≦ 2 is 800 to 9
It is 65 MHz. Therefore, in the inverted F antenna of the present embodiment, the bandwidth is 165 MHz and the fractional band is 18.7%, which is still larger than that in the first embodiment.

Since the ground wire 150 has a curved shape, it is possible to effectively use a small space without being bulky, and the directions of the currents flowing through the ground wire 150 are opposite to each other. Can be canceled, and in addition to the effect described in the first embodiment, an effect that the radiation pattern is not disturbed can be expected.

As in the case of the first embodiment described above, also in the present embodiment, the dimension of the ground plane 120 is too large to resonate at a desired frequency, and therefore the ground wire 150 is used for the ground plane 120. The electrical length was shortened equivalently. However, not limited to this, when the size of the ground plane is too small to resonate at a desired frequency, the ground wire 150 may be used to equivalently increase the electrical length of the ground plane 120.

(Third Embodiment) Next, with reference to FIG. 7 which is a plan view of an inverted F antenna according to a third embodiment of the present invention, the configuration and operation of the inverted F antenna according to the present embodiment will be described. . The inverted F antenna according to the present embodiment includes an antenna element 110 ′ having a feed pin 111 ′ and a main plate 1 arranged to face the antenna element 110 ′.
20 ', antenna element 110', and ground plane 120 '
And a ground wire 160 having a substantially spiral shape with a bend connected to a predetermined position C of the main plate 120 '.

The antenna element 110 'corresponds to the antenna element of the present invention, the feeding pin 111' corresponds to the feeding portion of the present invention, the main plate 120 'corresponds to the main plate of the present invention, and the short-circuit pin 130' is. The ground wire 160 corresponds to the short circuit portion of the present invention, and corresponds to the ground wire of the present invention.

The inverted F antenna of this embodiment has a structure similar to that of the inverted F antenna of the second embodiment described above (see FIGS. 4 to 5), but the ground wire 160 is the ground plane. The leg portion 161 along the long side of 120 'is connected to a predetermined position C on the long side, and the width is about the width of the short side of the main plate 120'.
It is characterized in that it has a substantially spiral shape with a bend formed on the outside of the short side on the antenna element 110 'side.

Here, the substantially spiral shape having a bend in the present embodiment will be described in more detail.

The ground line 160 is a bending point P which is bent at a right angle.
1 to P3. The bending point P from the tip of the ground wire 160
The tip portion 162 which is the portion up to 1 has a length D, and the leg portion 161 which is the portion from the predetermined position C which is the base of the ground wire 160 to the short side of the main plate 120 ′ has the length L. .

By changing the length D of the tip portion 162 of the ground wire 160 and the length L of the leg portion 161, the ground wire 160
The resonance frequency of the base plate 120 'can be made close to the resonance frequency of the antenna element 110' by adjusting the total length of the antenna and the predetermined position C (of course, by forming a slit (see FIG. 11) which will be described later). The resonant frequency of 110 'may be further adjusted).
That is, the main plate 120 'and the antenna element 110'
It is possible to control the electromagnetic field coupling with and generate these parallel resonances.

By adopting such an antenna device designing method, it is possible to realize an antenna device having excellent characteristics as described above.

The length of the main plate 120 'is as long as (1) λ / 2, which is a half of the wavelength λ in the frequency band used (when incorporated in the above-mentioned folding type mobile phone), (2) On the contrary, when the length is shorter than λ / 4, it is not possible to equivalently reduce or increase the size of the base plate 120 ′ by adjusting the total length of the ground wire 160 and the predetermined position C. Especially effective. Of course, the same applies to the first and second embodiments described above.

(Fourth Embodiment) Next, the present embodiment will be described with reference to FIG. 8A which is a plan view and FIG. 8B which is a side view of an inverted F antenna according to a fourth embodiment of the present invention. The configuration and operation of the inverted-F antenna of the form will be described. The inverted-F antenna of the present embodiment connects the antenna element 110 ′ having the feeding pin 111 ′, the base plate 120 ′ arranged to face the antenna element 110 ′, and the antenna element 110 ′ and the base plate 120 ′. It is provided with a short-circuit pin 130 'and a ground wire 170 having a curved shape connected to a predetermined position of the ground plate 120'.

The ground line 170 corresponds to the ground line of the present invention.

The inverted F antenna of this embodiment has a structure similar to that of the inverted F antenna of the third embodiment described above (see FIG. 7), but the ground wire 170 is the ground plane 12.
Located in a plane different from 0 '(see FIG. 8 (b))
It is characterized by points (in the above-described first to third embodiments, the ground line is located in the same plane as the ground plane).

When the inverted F antenna of this embodiment is built in a mobile phone, the display is arranged on the side opposite to the antenna element 110 'with respect to the main plate 120'. Since the side on which the display is arranged hits the side close to the human body during a mobile phone call, the height H ′ from the main plate 120 ′ (see FIG. 8B) is taken to influence the antenna element 110 ′ from the human body. By reducing (for example, characteristic deterioration caused by a change in current distribution caused by contact with the head or ear), the antenna gain is reduced and the SAR (specific absorption rate, Specific Absorb) is reduced.
It is possible to suppress an increase in the charge rate).
Of course, by taking the height H '(see Fig. 8 (b)),
The influence of the antenna element 110 'on the human body (for example, the adverse effect of the strong electric field on the human body physiology) can be reduced at the same time.

In this embodiment, the ground wire 17
Although 0 is located in a plane parallel to the ground plane 120 ', the ground wire 170 is not limited to this.
It suffices if it is located in a plane different from that of 20 '. More specifically, the ground line 170 may be located in a plane inclined so as not to be parallel to the ground plane 120 '. In short, the ground wire may be arranged so that a portion where the electric field distribution of the ground wire is large (that is, a portion where electromagnetic field coupling with the human body is strong) is separated from the human body.

(Fifth Embodiment) Next, with reference to FIG. 9 which is a plan view of an inverted F antenna according to a fifth embodiment of the present invention, the configuration and operation of the inverted F antenna according to the present embodiment will be described. .

The inverted F antenna of this embodiment has an antenna element 110 'having a feed pin 111' and a main plate 12 arranged so as to face the antenna element 110 '.
0 ″, a short-circuit pin 130 ′ connecting the antenna element 110 ′ and the ground plane 120 ″, and a ground wire 180 having a substantially spiral shape with a bend connected to a predetermined position C ′ of the ground plane 120 ″. .

The ground line 180 corresponds to the ground line of the present invention.

The inverted F antenna of this embodiment has a structure similar to that of the inverted F antenna of the third embodiment described above (see FIG. 7), but the ground wire 180 is
The leg 181 along the long side of 0 ″ is connected to a predetermined position C ′ in the middle of the long side, and is formed inside the short side on the antenna element 110 ′ side that is less than the width of the short side of the main plate 120 ″. It is characterized by having a substantially spiral shape with a bend (in the above-described third embodiment, the ground wire 160 is formed outside the short side on the antenna element 110 'side).

When the inverted F antenna of this embodiment is built in a mobile phone, the outside of the short side on the antenna element 110 'side is the side close to the human body during a mobile phone call. Therefore, the ground wire 180 is arranged inside the short side, and the ground wire length is adjusted so that the peak point of the current flowing therethrough is separated from the human body (for example, in consideration of the change in the current distribution caused by holding by the fingers). As a result, similarly to the case of the fourth embodiment described above, it is possible to suppress a decrease in antenna gain and an increase in SAR.

In the above, the first to fifth embodiments have been described in detail.

The ground wire of the present invention is one in the above-described embodiment. However, the ground line of the present invention is not limited to this, and the ground line 170 (see FIG.
(A) to (b)) and the ground wire 180 (see FIG. 9). In short, the ground wire of the present invention may be singular or plural. By making each line correspond to a predetermined operating frequency, the ground plane resonates at the resonance frequency corresponding to each of multiple ground lines, so it can be mounted on a dual-band compatible or triple-band compatible mobile phone, etc. The characteristics can be realized.

Further, the ground wire of the present invention is constructed as a member integrated with the ground plate in the above-mentioned present embodiment. However, the present invention is not limited to this, and the ground wire of the present invention may be configured by a separate part as a member different from the ground plate. For example, by providing connection terminals at predetermined positions C (see FIG. 7) of the main plate 120 ′ and terminal positions of the leg portions 161 (see FIG. 7) of the ground wire 160 so that they can be connected, the main plate 120 ′ is Even when it is composed of a metal chassis, an LCD holder, a substrate, etc., it becomes easy to adjust the ground wire length and the ground wire connecting position. Further, (1) the ground wire can be attached to the inner wall portion of the casing of a mobile phone or the like, and (2) the ground wire can be formed as a GND pattern on a flexible substrate, which improves the degree of freedom in design, Characteristic variations during mass production are reduced.

Further, the ground wire of the present invention has a ground electrode (G
It may be shared with ND). For example, (1) as shown in FIG. 10 which is a plan view of an inverted F antenna in which the ground wire according to the present invention is shared with the ground electrode, GN of the camera substrate 201 for mounting the camera 200.
It may be shared with D, or (2) it may be shared with GND of the receiver and the audio speaker. The number of parts can be reduced by sharing the ground electrode. Of course, the commonization with the ground electrode may be performed by utilizing the structure in which the lateral slit S1 is provided as shown in FIG. 17, or as shown in FIG. A slit S1 in the direction and a slit S2 to the ground line side may be used for the structure, and as shown in FIG. 19, the slit S1 in the lateral direction and the slit S3 to the ground plate side are formed. It may be performed using the provided structure. Note that FIG. 17 is a plan view of an inverted F antenna in which the structure in which the lateral slit S1 according to the present invention is provided is used in common with the ground electrode, and FIG. 18 is a lateral view according to the present invention. FIG. 19 is a plan view of an inverted F antenna in which a slit S1 and a ground-side slit S2 are provided for common use with a ground electrode, and FIG. 19 is a lateral slit S1 according to the present invention. FIG. 11 is a plan view of an inverted F antenna in which a structure in which a slit S3 is provided on the side of the ground plane and the ground electrode are used in common.

Further, the ground wire of the present invention has a linear shape or a shape having a bend in the above-described present embodiment. However, not limited to this, the ground wire of the present invention may have a shape having a single curve or a plurality of curves. For example, FIG. 20 (a) which is a plan view of an inverted F antenna in which the ground wire 190 according to the present invention has a curved shape and the inverted F antenna in which the ground wire 190 ′ according to the present invention has a curved shape.
As shown in FIG. 20 (b), which is a plan view of the antenna, the ground wires 190 and 190 ′ of the antenna device having a configuration similar to that of the antenna device according to the first embodiment may be curved. Since it becomes easy to store the ground wire in a limited space, the degree of freedom in design is further improved. Also,
The ground wire of the present invention may have a shape that cannot be included in a plane, such as a helical shape. For example, as shown in FIG. 25, which is a perspective view of an inverted F antenna having a ground wire 150 ′ having a helical shape according to the present invention, an antenna device having a configuration similar to that of the antenna device according to the second embodiment is shown. The ground wire 150 'may have a helical shape. Since the physically occupied volume of the ground wire portion can be reduced, the degree of freedom in design is further improved.

The ground wire of the present invention may have a coil and / or a capacitor in a part thereof. For example, (1) As shown in FIG. 21, which is a plan view of an inverted-F antenna in which a ground wire 140 'according to the present invention has a coil L1 and a capacitor C1 in a part thereof, the antenna of the first embodiment is provided. A coil L1 and a capacitor C1 are provided in a part of a ground wire 140 'of an antenna device having a configuration similar to the device.
May be used to change the electrical characteristics of the ground plane, and (2) is a plan view of an inverted F antenna according to the present invention, in which the ground wire has a coil L2 and a capacitor C2 in a part thereof. As shown in FIG. 24, the coil L2 and the capacitor C2 are used in a part of the ground wire of the antenna device having a configuration similar to that of the antenna device of the present embodiment (see FIG. 17), so that the electricity of the ground plane is reduced. The physical characteristics may be changed. Since it is possible to change the electrical length of the ground wire by changing the inductance of the coil and the capacity of the capacitor, it is possible to further improve the degree of freedom in design by using these (original adjustment of the length of the ground wire). Although it adjusts the electrical length of the ground plane by the above, even if the length of the ground wire deviates from the optimum size during mass production,
It is possible to correct the deviation by using a coil and a capacitor).

The ground wire of the present invention may be wholly opposed to the antenna element or may not be entirely opposed to the antenna element, or at least a part thereof may be opposed to the antenna element. You don't have to.

Further, the antenna element of the present invention may have a predetermined slit. For example, the slit S may be provided as shown in FIG. 11 which is a plan view of the inverted F antenna in which the antenna element according to the present invention has the predetermined slit S. By providing slits and realizing a plurality of types of paths on the same antenna element, the ground plane resonates at the resonance frequency corresponding to each of the plurality of types of paths, so that wide band characteristics can be realized.

Further, the short-circuit portion of the present invention has a plurality of short-circuit pins each corresponding to a predetermined operating frequency, and is provided with a switch circuit for switching to the short-circuit pin to be used among the plurality of short-circuit pins. It may be. For example, as shown in FIG. 12, which is a plan view of an inverted F antenna in which the short-circuit portion according to the present invention has a plurality of short-circuit pins and is provided with a switch circuit for switching to the short-circuit pin to be used. In addition to the short-circuit pin 130 ', a short-circuit pin 130 "is provided, and when the low frequency is used, the on-off switch circuit 3
00 may be turned off, and when using a high frequency, the on / off switch circuit 300 may be turned on to switch the conduction of the diode 301. Since the antenna element resonates at a resonance frequency corresponding to each of the plurality of short-circuit pins, the antenna element can be mounted on a dual-band compatible or triple-band compatible mobile phone or the like to realize wide band characteristics. of course,
A plurality of short-circuit pins may be selected so that communication at a more important frequency can be performed more reliably.

It should be noted that the antenna device 1 of the embodiment of the present invention as shown in FIG. 22 which is a configuration diagram of the communication device of the embodiment of the present invention, and the antenna device 1 are used. Transmitting means 2 for transmitting a radio wave signal and receiving means 3 for receiving a radio wave signal using the antenna device 1.
And a signal processing circuit 4 for performing signal processing for transmitting and receiving radio signals are included in the present invention.

Specifically, a communication device of one embodiment of the present invention is, for example, a plan view of the communication device of one embodiment of the present invention shown in FIG. 23 (a) and one embodiment of the present invention. 23 (b), which is a side view of the communication device of FIG.

That is, the antenna / liquid crystal integrated module 1101 includes a liquid crystal display 1110, a built-in antenna 1105 provided on the back surface of the liquid crystal display 1110 and using the antenna device according to the embodiment of the present invention,
Substrate 11 provided on the lower surface of liquid crystal display 1110
06, and a driver circuit 1107 provided on the back surface of the substrate 1106. Liquid crystal display 1110
Is a display body 1102 and a display body 1
Metallic reflector 1103 provided on the back side of the image display surface of 102, display body 1102 and reflector 11
03 and a frame 1104 having a non-conductor U-shape for housing the driver circuit 1107.
The image is displayed on the image display surface of the display body 1102. Antenna element part 11 on a rectangular plate
The end of 05a is electrically connected to the reflection plate 1103 via a metal connection portion 1105c, and the antenna element portion 1105a is provided in a surface facing the display body 1102 and the reflection plate 1103. Reflector 110
It operates by the power feeding from the feeding point 1105b located on the upper side. Input / output to / from the feeding point 1105b is performed by the substrate 110.
6 is supplied from the transmitting means and the receiving means (not shown). In the antenna / liquid crystal integrated module 1101, the antenna element portion 1105a is directly provided on the back surface of the liquid crystal display 1110, and the reflection plate 1103 and the antenna element portion 1105a are connected by the connection portion 1105c. It functions as an earth ground plate of the antenna element portion 1105a.

As a more specific example of the communication device of the present invention, there is a foldable type mobile phone in which the above-described inverted F antenna of the present embodiment is housed in an upper casing or a lower casing.
For example, FIG. 26 is a side view of a foldable mobile phone (No. 1) which is an embodiment of a communication device of the present invention.
, An upper housing 2100 for accommodating a display 2110, a key portion 2210, and a lower substrate 22.
20, a lower housing 2200 for housing an inverted F antenna 2230 having a ground wire 2231 (illustrated schematically), which has a configuration similar to that of the inverted F antenna of the second embodiment (see FIG. 4). And the upper housing 2100 and the lower housing 2
A foldable mobile phone having a metal hinge part 2300 connecting the mobile phone 200 and the mobile phone 200 is a specific example of the communication device of the present invention. FIG. 2 is a side view of a foldable mobile phone (No. 2) which is an embodiment of the communication device of the present invention.
7, a display 3110, an upper substrate 3120, and a ground wire 3131 (schematically illustrated) having a configuration similar to that of the above-described inverted F antenna of the second embodiment (see FIG. 4). Inverted F antenna 3130 having
An upper housing 3100 for housing a key portion 3210, a lower substrate 3220 for housing a lower housing 3200, and a metal hinge portion 3 connecting the upper housing 3100 and the lower housing 3200.
A folding type mobile phone including the mobile phone 300 and the mobile phone 300 is a specific example of the communication device of the present invention. The lower housing 2200 corresponds to the first housing of the present invention, the upper housing 2100 corresponds to the second housing of the present invention, and the metal hinge part 2300 corresponds to the hinge part of the present invention. The upper housing 3100 corresponds to the first housing of the present invention, and the lower housing 3200 corresponds to the second housing of the present invention.
The metal hinge part 3300 corresponds to the hinge part of the present invention.

Further, for example, a foldable mobile phone (part 3) which is an embodiment of the communication device of the present invention.
28, which is a side view of FIG. 28, and FIG. 29, which is a perspective view of a folding type mobile phone (part 3) which is an embodiment of a communication device of the present invention, as shown in FIG.
Inverted F antenna 4210 is housed in 200, and upper housing 4100 and lower housing 4200 have metal hinge portion 4
300, and the GND (ground) of the lower substrate 4220 housed in the lower housing 4200 and the metal hinge portion 4300 are electrically connected to each other at least at one place via the connection element 4400. 29 (as shown in FIG. 29, only one end of both ends of the metal hinge portion 4300 is connected to the GND of the lower substrate 4220, and the other end is opened). Of course, when the upper housing 4100 or the substrate housed in the upper housing 4100 is operated as the GND of the antenna, the upper housing 4100 or the substrate housed in the upper housing 4100 is operated. It suffices that the GND and the metal hinge portion 4300 are electrically connected at at least one place). The inverted F antenna 4210 corresponds to the predetermined antenna device of the present invention, the lower substrate 4220 corresponds to the predetermined substrate of the present invention, and the lower housing 4200 corresponds to the first housing of the present invention. The upper housing 4100 corresponds to the second housing of the present invention, and the metal hinge part 4300 corresponds to the hinge part of the present invention. By doing so, the metal hinge portion functions as a part of the ground wire, and thus the inverted F antenna 4210 may be a conventional inverted F antenna having no ground wire. Of course, when it is desired to resonate the ground plane at a plurality of resonance frequencies, the inverse F of the above-described embodiment is used.
An antenna may be used. Note that the connection element 4400
The metal hinge portion 4300 and the metal hinge portion 4300 do not have to be directly connected, and may be connected, for example, via a capacitor. In short, if they are electrically connected in a high frequency region, Good.

The antenna device of the present invention is an inverted F antenna in the above-described present embodiment. However, not limited to this, the antenna device of the present invention may be an unbalanced antenna. However, it is desirable to use the inverted F antenna from the viewpoint of widening the band and downsizing.

[0101]

The first aspect of the present invention can provide, for example, an inverted F antenna that is made thin.

The second aspect of the present invention can provide, for example, an inverted F antenna which is made thinner.

The third aspect of the present invention can provide, for example, an inverted F antenna which is made thinner.

The fourth aspect of the present invention can provide, for example, an inverted F antenna in which a decrease in antenna gain and an increase in SAR are suppressed.

The fifth aspect of the present invention provides, for example, an inverted F antenna in which the influence on the human body and the influence on the human body when using a mobile phone are reduced, and the decrease in antenna gain and the increase in SAR are further suppressed. You can

The sixth aspect of the present invention can provide, for example, a mobile phone with a reduced number of parts.

The seventh aspect of the present invention can provide a portable telephone in which the number of parts is further reduced by, for example, making the receiver and the voice speaker common with the GND.

The eighth aspect of the present invention can provide, for example, an inverted F antenna in which the degree of freedom in design is improved and the characteristic variation during mass production is suppressed.

The ninth aspect of the present invention can provide, for example, a mobile phone with improved design flexibility and suppressed characteristic variations during mass production.

The tenth aspect of the present invention can provide, for example, an inverted F antenna with improved design freedom.

The eleventh aspect of the present invention can provide, for example, a mobile phone having wide band characteristics and compatible with dual bands and triple bands.

The twelfth aspect of the present invention can provide, for example, an inverted F antenna with improved design freedom.

The thirteenth aspect of the present invention can provide, for example, an inverted F antenna with improved design freedom.

The fourteenth aspect of the present invention can provide, for example, an inverted F antenna with a higher degree of freedom in design.

The fifteenth aspect of the present invention can provide, for example, a dual-band compatible or triple-band compatible mobile phone having a wide band characteristic.

The sixteenth aspect of the present invention can provide, for example, an inverted F antenna in which a decrease in antenna gain and an increase in SAR are further suppressed.

The seventeenth aspect of the present invention can provide, for example, a portable telephone having a wide band characteristic which is realized to be thin.

The eighteenth aspect of the present invention can provide, for example, a folding type portable telephone having a wide band characteristic which is realized to be thin.

The nineteenth aspect of the present invention can provide, for example, a thin folding type mobile phone.

The twentieth aspect of the present invention can provide, for example, a thinner folding type mobile phone.

The twenty-first aspect of the present invention can provide, for example, a method of designing an inverted F antenna with an improved degree of freedom.

The 22nd aspect of the present invention can provide, for example, a method of designing an inverted F antenna with a higher degree of freedom.

As is apparent from the above description, the present invention has an advantage that a folding type mobile phone can be thinned.

[Brief description of drawings]

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

FIG. 2 is a plan view of the inverted F antenna according to the first embodiment of the present invention.

FIG. 3A is a Smith chart for explaining the characteristics of the input impedance in which the antenna is viewed from the feeding point of the inverted F antenna according to the first embodiment of the present invention. (B) It is explanatory drawing of the same VSWR (voltage standing wave ratio).

FIG. 4 is a perspective view of an inverted F antenna according to a second embodiment of the present invention.

FIG. 5 is a plan view of an inverted F antenna according to a second embodiment of the present invention.

FIG. 6A is a Smith chart for explaining the characteristics of the input impedance in which the antenna is viewed from the feeding point of the inverted F antenna according to the second embodiment of the present invention. (B) It is explanatory drawing of the same VSWR (voltage standing wave ratio).

FIG. 7 is a plan view of an inverted F antenna according to a third embodiment of the present invention.

FIG. 8A is a plan view of the inverted F antenna according to the fourth embodiment of the present invention. (B) It is a side view of the inverted F antenna of Embodiment 4 of the present invention.

FIG. 9 is a plan view of an inverted F antenna according to a fifth embodiment of the present invention.

FIG. 10 is a plan view of an inverted F antenna in which a ground wire is shared with a ground electrode according to the present invention.

FIG. 11 is a plan view of an inverted F antenna in which the antenna element has a predetermined slit S according to the present invention.

FIG. 12 is a plan view of an inverted F antenna according to the present invention, in which the short-circuit portion has a plurality of short-circuit pins, and a switch circuit for switching to the short-circuit pins to be used is provided.

FIG. 13 is a perspective view of a conventional inverted F antenna.

FIG. 14 is a plan view of a conventional inverted F antenna.

FIG. 15 (a) Conventional inverted F antenna (d = 13 mm)
It is a Smith chart for explaining the characteristic of the input impedance which looked at the antenna from the feeding point. (B) It is explanatory drawing of the same VSWR (voltage standing wave ratio).

FIG. 16A is a Smith chart for explaining the characteristic of the input impedance in which the antenna is viewed from the feeding point of the conventional inverted F antenna (d = 2 mm). (B) It is explanatory drawing of the same VSWR (voltage standing wave ratio).

FIG. 17 is a plan view of an inverted F antenna according to the present invention in which a structure provided with a lateral slit S1 is used in common with a ground electrode.

FIG. 18 is a plan view of an inverted F antenna according to the present invention in which a structure in which a slit S1 in a lateral direction and a slit S2 to the ground line side are provided is used in common with a ground electrode.

FIG. 19 is a plan view of an inverted F antenna according to the present invention in which a structure provided with a lateral slit S1 and a slit S3 toward the ground plane is used in common with a ground electrode.

FIG. 20 (a) is a plan view of an inverted F antenna having a shape in which a ground wire 190 has a curve according to the present invention. (B) It is a top view of the inverted F antenna which has the shape which the ground wire 190 'has a curve concerning this invention.

FIG. 21 is a plan view of an inverted F antenna according to the present invention, in which a ground wire 140 ′ has a coil L1 and a capacitor C1 in a part thereof.

FIG. 22 is a configuration diagram of a communication device according to an embodiment of the present invention.

FIG. 23 (a) is a plan view of the communication device according to the embodiment of the present invention. (B) It is a side view of the communication apparatus of one embodiment of the present invention.

FIG. 24 is a diagram showing a ground wire according to the present invention, a part of which is a coil L;
2 is a plan view of an inverted F antenna having a capacitor 2 and a capacitor C2. FIG.

FIG. 25 is a perspective view of an inverted F antenna in which a ground wire 150 ′ has a helical shape according to the present invention.

FIG. 26 is a side view of a folding type mobile phone (No. 1) which is an embodiment of the communication device of the present invention.

FIG. 27 is a side view of a foldable mobile phone (No. 2) which is an embodiment of the communication device of the present invention.

FIG. 28 is a side view of a folding type mobile phone (No. 3) which is an embodiment of the communication device of the present invention.

FIG. 29 is a perspective view of a foldable mobile phone (No. 3) which is an embodiment of the communication device of the present invention.

[Explanation of symbols]

110 antenna element 111 power supply plate 112 feeding point 120 main plate 130 short-circuit plate 140 ground line

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kenichi Yamada             3-1, Tsunashima-Higashi 4-chome, Kohoku-ku, Yokohama-shi, Kanagawa             No. Panasonic Mobile Communicator             Within Chonz Co., Ltd. (72) Inventor Shinji Higuchi             1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric             Sangyo Co., Ltd. F-term (reference) 5J045 AA01 AB01 AB05 BA01 CA01                       DA08 GA04 LA01 NA03 NA04

Claims (22)

[Claims] 1. An antenna element having a power feeding section, a ground plane arranged to face the antenna element, a short-circuit section connecting the antenna element and the ground plane, and a ground plane connected to a predetermined position of the ground plane. An antenna device comprising: (1) a straight line shape; or (2) a single or a plurality of ground wires having a curved or curved shape. 2. An antenna element having a feeding portion, a base plate which is arranged facing the antenna element and has a substantially rectangular plate shape having short sides and long sides, and which connects the antenna element and the base plate. A short-circuit part and a single or a plurality of ground wires having a predetermined shape connected to a predetermined position of the ground plane, wherein the antenna element is arranged on the short side, and all or a part of the ground wire is An antenna device, which is connected to a corner of the base plate on the antenna element side and has a substantially spiral shape formed outside the short side on the antenna element side having a width equal to or smaller than the short side. 3. An antenna element having a feeding portion, a base plate having a substantially rectangular plate shape having short sides and long sides, which is arranged so as to face the antenna element, and the antenna element and the base plate are connected to each other. A short-circuit part and a single or a plurality of ground wires having a predetermined shape connected to a predetermined position of the ground plane, wherein the antenna element is arranged on the short side, and all or a part of the ground wire is An antenna device having a substantially spiral shape in which a leg portion along a long side of the main plate is connected in the middle of the long side and is formed outside a short side of the antenna element side having a width equal to or smaller than the short side. 4. The antenna device according to claim 1, wherein at least a part of the ground wire is located in a plane different from that of the ground plane. 5. The antenna device for use in a mobile phone, wherein the antenna device is located in a plane different from that of the main plate when the user uses the mobile phone. The antenna device according to claim 4, wherein the antenna device is located on a side farther from the portion. 6. The antenna device according to claim 1, wherein the ground wire is shared with a ground electrode. 7. The antenna device is an antenna device for use in a mobile phone having a camera and / or a receiver, and the ground electrode is a ground electrode of the camera and / or the receiver. Antenna device. 8. The antenna device according to claim 1, wherein the ground wire is configured as a member different from the ground plate. 9. The antenna device is an antenna device for use in a mobile phone having a housing, and is configured as a member different from the base plate to be attached to an inner wall portion of the housing. The antenna device according to claim 8, which is configured as a member. 10. The antenna device according to claim 1, wherein at least a part of the ground wire does not face the antenna element. 11. The short circuit section has a plurality of short circuit pins respectively corresponding to a predetermined operating frequency, and further comprises a switch circuit for switching to a short circuit pin to be used among the plurality of short circuit pins. The antenna device according to claim 1. 12. The antenna device according to claim 1, wherein the antenna element has a predetermined slit. 13. The antenna device according to claim 1, wherein the ground wire has a coil and / or a capacitor in a part thereof. 14. The antenna device according to claim 13, wherein the coil and / or the capacitor is used to equivalently adjust an electrical length of the ground wire. 15. The antenna device according to claim 1, wherein a plurality of the ground lines are provided, and each of the ground lines corresponds to a predetermined operating frequency. 16. The antenna device according to claim 4, wherein the ground wire has a helical shape. 17. An antenna device according to claim 1, a transmitting means for transmitting a radio signal using the antenna device, and a receiving means for receiving a radio signal using the antenna device. Equipped communication device. 18. The antenna device is an antenna device for use in a mobile phone, wherein a first housing that houses the antenna device and a second housing that is different from the first housing. The body further includes a hinge portion connecting the first casing and the second casing.
7. The communication device according to 7. 19. A predetermined antenna device, a first housing for accommodating the antenna device and a predetermined substrate, a second housing different from the first housing, and the first housing. A communication device comprising: a hinge part that connects a body and the second housing, and the ground of the substrate and the hinge part are electrically connected. 20. The electrical connection is made so that one end of both ends of the hinge portion is connected to the ground of the substrate and the other end is opened. 19. The communication device according to item 19. 21. An antenna device designing method for the antenna device according to claim 1, wherein the predetermined position and / or the predetermined shape is adjusted based on a predetermined rule. 22. The ground wire has a coil and / or a capacitor in a part thereof, and the coil and / or the capacitor is used to equivalently adjust an electric length of the ground wire. 21
The antenna device design method described.