JP2002170716A - Chip antenna and radio terminal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chip antenna having no directional properties and being capable of improving mounting properties and a radio terminal device. SOLUTION: The chip antenna has a base 11, a pair of terminal sections 15 and 26 installed to the base 11, and a spiral antenna element section mounted on the base 11 electrically connected to a pair of the terminal sections 15 and 16 and secured between a pair of the terminal sections 15 and 16. Overall length of the antenna is set in L, and the center of the antenna element section is set within the range of 0.4×L of a central section with the exception of sections within the range of 0.3×L respectively from both end faces.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chip antenna and a wireless terminal device suitably used for electronic equipment for performing wireless communication such as mobile communication.

[0002]

2. Description of the Related Art Rod type antennas and planar antennas are
Although it is generally used as an antenna for wireless communication, chip-type antennas have recently attracted attention.
Such a chip antenna can be directly mounted on a substrate of a mobile phone or the like, does not protrude significantly outside, and can realize a reduction in the size of the device.

As prior examples, there are JP-A-9-64627 and JP-A-9-74309.

[0004]

However, in the above configuration, the mounting direction is determined when mounting on a board, and it is necessary to pay attention to the direction during mounting. Was bad.

An object of the present invention is to solve the above-mentioned conventional problems and to provide a chip antenna and a radio terminal device capable of improving mountability.

[0006]

SUMMARY OF THE INVENTION The present invention provides a base, a pair of terminals provided on the base, and a pair of terminals electrically connected to the pair of terminals provided on the base. And a spiral antenna element portion provided between them, and having a total length of L, wherein the center of the antenna element portion excludes a range of 0.3 × L from both end faces. Of 0.4 × L.

[0007]

DETAILED DESCRIPTION OF THE INVENTION The invention according to claim 1 comprises a base,
A pair of terminal portions provided on the base, and a spiral antenna element portion provided on the base and electrically connected to the pair of terminal portions and provided between the pair of terminal portions; A chip antenna having a total length of L, wherein the center of the antenna element portion is 0.3
By providing the chip antenna in a range of 0.4 × L in the central portion excluding the range of × L, any one of the pair of terminal portions can be used as the feeding portion, The difference in operating frequency can be reduced, and either terminal may be used as the power supply, so that the mountability is extremely improved.

According to a second aspect of the present invention, there is provided the chip antenna according to the first aspect, wherein the antenna element portion is formed of a spiral conductive film formed over the entire side surface of the base. Since the conductive film is fixed to the base in close contact with the base, no variation occurs and stable characteristics can be obtained for a long period of time.

According to a third aspect of the present invention, a spiral conductive film is formed by providing a conductive film all around the side surface of the base and forming a spiral groove in the conductive film all around the side surface. According to the chip antenna of the second aspect, the characteristics can be easily adjusted by adjusting the width and the length of the groove.

According to a fourth aspect of the present invention, there is provided the chip antenna according to the second aspect, wherein a protective material made of a metal film having high corrosion resistance is provided on the surface of the conductive film.
The weather resistance of the conductive film can be increased, and even if a protective material is provided, the change in operating frequency is very small, and variations in characteristics can be reduced.

According to a fifth aspect of the present invention, the metal film is made of at least one material selected from the group consisting of gold, platinum, palladium, silver, tungsten, titanium, nickel and tin, or a material selected from the material group. 5. The chip antenna according to claim 4, wherein the chip antenna is constituted by at least one of an alloy material of an element other than the material group. A free chip antenna can be provided.

According to a sixth aspect of the present invention, there is provided a chip antenna according to the second aspect, wherein an electrodeposited resin film formed by an electrodeposition method is provided on the surface of the conductive film. Since the protective film can be formed and the groove is not completely filled, even after the protective material is formed, the variation in characteristics is small and the productivity is high.

According to a seventh aspect of the present invention, in the chip antenna according to the second aspect, a buffer layer is provided between the conductive film and the base. In addition, characteristic deterioration due to peeling of the conductive film can be prevented.

According to an eighth aspect of the present invention, there is provided the chip antenna according to the seventh aspect, wherein at least one of a carbon film, a carbon-containing film, and a Ni alloy film is provided as the buffer layer. Can be improved without deteriorating the adhesion between the conductive film and the base.

According to a ninth aspect of the present invention, the conductive film itself is made of gold,
At least one material selected from the group consisting of platinum, palladium, silver, tungsten, titanium, nickel and tin, or at least one of a material selected from the material group and an alloy material of an element other than the material group With the chip antenna according to claim 2, it is not necessary to point a protective material,
Moreover, since the structure is simple, productivity is dramatically improved.

According to a tenth aspect of the present invention, in the chip antenna according to the third aspect, the number of turns of the spiral groove is configured to be a natural number times, and furthermore, one of the left and right terminal portions is provided. Variations in characteristics can also be suppressed as a power supply unit.

According to an eleventh aspect of the present invention, there is provided the chip antenna according to the third aspect, wherein the base has a prism shape, and both ends of the groove are arranged on the same side surface or the same ridge line. This makes it possible to increase the number of turns of the spiral groove to a natural number times or a number close to the natural number, so that the variation in characteristics can be suppressed even if either of the left and right terminals is used as the power supply unit.

According to a twelfth aspect of the present invention, the base is formed in a columnar shape and the imaginary line connecting both ends of the groove is substantially parallel to the central axis along substantially the entire length (intersection angle is ± 5 degrees). Since the number of turns of the spiral groove can be a natural number times or a number close to the natural number by using the chip antenna according to the third aspect of the present invention, the left and right terminal portions can be used as a power supply portion. In addition, variations in characteristics can be suppressed.

According to a thirteenth aspect of the present invention, in the chip antenna according to the first aspect, a linear conductor wire is spirally wound around a side surface of the base as the antenna element portion. So that the gain can be increased,
Antenna characteristics can be improved.

According to a fourteenth aspect of the present invention, terminal portions are provided on all side surfaces at both ends of the base.
By using the above-described chip antenna, mounting can be performed in any direction with the center line in the longitudinal direction as the rotation axis, so that mounting performance can be further improved.

According to a fifteenth aspect of the present invention, at least one of a protective layer and a bonding layer is provided on the conductive film as a terminal part. Better bondability with the circuit board, stable characteristics over a long period of time, and corrosion of the terminals themselves can also be suppressed, thus obtaining stable characteristics over a long period of time. Can be.

According to a sixteenth aspect of the present invention, there is provided the chip antenna according to the first aspect, wherein the terminals are formed by fitting caps made of a conductive material to both ends of the base. Thus, the antenna element portion can be lifted from the substrate or the like depending on the thickness of the cap, so that a change in characteristics can be prevented.

According to a seventeenth aspect of the present invention, the bonding antenna is provided over the cap and the antenna element portion, and the electrical connection between the cap and the conductive film is achieved by the chip antenna according to the sixteenth aspect. This can be performed over a wide area, and characteristics can be improved.

[0024] The invention according to claim 18 is characterized in that:
18. The chip antenna according to claim 17, wherein at least one of tin, tin alloy (excluding tin-lead alloy), gold, and gold alloy is provided, and can be directly mounted on a circuit board.
Moreover, it can be a lead-free component.

According to a nineteenth aspect of the present invention, there is provided a signal conversion means for converting a voice into a voice signal or data into a data signal, an operation means for inputting a telephone number and the like, and a display for displaying an incoming call display and a telephone number. Means, a transmitting means for modulating a voice signal or a data signal and converting it to a transmission signal, and a receiving means for converting a received signal to a voice or data signal,
19. The apparatus according to any one of claims 1 to 18, which transmits or receives at least one of the transmission signal and the reception signal, and a wireless terminal apparatus including a control unit that controls each unit, thereby making the apparatus inexpensive. By mounting an antenna that can be manufactured, has good characteristics, and can be surface-mounted, a small and high-performance device can be provided.

According to a twentieth aspect of the present invention, a first antenna for transmitting / receiving a signal to / from a base station, a first transmitting / receiving unit for converting a signal transmitted / received by the first antenna to a data signal, A second antenna for transmitting and receiving signals to and from a portable terminal device provided in the vicinity, and a second transmitting and receiving unit for converting a signal transmitted and received by the second antenna to a data signal; 20. At least one of said antenna and said second antenna
Providing a wireless terminal device characterized by having the antenna structure described above, the device can be manufactured at low cost, and a small, high-performance device can be provided by mounting an antenna with good characteristics and surface mounting. it can.

According to a twenty-first aspect of the present invention, there is provided a wireless terminal device according to the twentieth aspect, a portable terminal device for transmitting / receiving data to / from the wireless terminal device, and data or voice communication between the wireless terminal device. A base station that exchanges signals,
A server connected to the base station via a public line, an information network connected to the server via a line 205, and a specific or unspecified user or a user having a provider connected to the information network. By using a data transmission / reception system, a stable communication system can be constructed.

Hereinafter, embodiments of the chip antenna and the wireless terminal device according to the present invention will be described.

1 and 2 are a perspective view and a side sectional view, respectively, showing a chip antenna according to an embodiment of the present invention.

In FIG. 1, reference numeral 11 denotes a base which is formed by subjecting an insulating material or the like to press working, extrusion, or the like.
Reference numeral 2 denotes a conductive film provided on the base 11.
2 is formed on the side surface of the base 11 by a vapor deposition method such as a plating method or a sputtering method. 13 is a groove provided on the base 11 and the conductive film 12. The groove 13 is formed by irradiating the conductive film 12 with a laser beam or the like, or is formed mechanically by applying a grindstone or the like to the conductive film 12. Or by selective etching using a resist or the like. By providing this groove 13 in a spiral shape,
The spiral conductive film 12 is formed on the conductive film 12. Further, the groove 13 is preferably formed in both the base 11 and the conductive film 12. With such a configuration, the conductive film 12 can be completely cut, and deterioration of characteristics can be prevented. Reference numeral 14 denotes a protective material provided on the conductive film 12, and reference numerals 15 and 16 denote terminal portions each having a terminal electrode formed on an end face of the base 11, and a groove 13 is provided between the terminal portions 15 and 16. Is provided.

With such a configuration, the spiral conductive film 12 (antenna element portion) can be formed by forming the conductive film 12 in the spiral groove 13, so that the productivity is very good and the groove is formed. By appropriately setting the width of the conductive film 13 and the width of the spiral conductive film 12, the characteristics can be easily adjusted.
6 has a regular polygonal shape or a circular shape, so that the characteristics do not change regardless of which side surface of the terminal portions 15 and 16 is used as the mounting surface, and whichever of the terminal portions 15 and 16 is used as the power supply portion. That is, since there is no directionality, the mountability is dramatically improved. Further, since the conductive film 12 is fixed to the base 11, the pitch of the spiral conductive film does not change during use of the product of the present invention, so that stable characteristics can be obtained for a long period of time. be able to.

In the drawing, the spiral conductive film 1 is shown.
Although the width and pitch of 2 are described as being equal,
The width and pitch of the conductive film 12 may be changed substantially symmetrically with respect to the center of the antenna element portion, without necessarily being equal.

Further, the chip antenna of the present embodiment
The practical frequency band corresponds to a high frequency range of 0.7 to 6.0 GHz, and the length L1, height L2, width L of the chip antenna
3 is preferably as follows.

L1 = 4.0-40.0 mm L2 = 0.5-5.0 mm L3 = 0.5-5.0 mm When L1 is 4.0 mm or less, a required inductance value, that is, a desired frequency Antenna operation cannot be obtained. Further, when L1 exceeds 40.0 mm, the element itself becomes large, and it is not possible to reduce the size of a circuit board or the like on which an electronic circuit or the like is formed (hereinafter abbreviated as a circuit board or the like). It is not possible to reduce the size of an electronic device or the like on which a circuit board or the like is mounted. Also, L
If each of L2 and L3 is 0.5 mm or less, the mechanical strength of the element itself becomes too weak, and the element may be broken when mounted on a circuit board or the like by a mounting apparatus or the like. On the other hand, if L2 and L3 are not less than 5.0 mm, the elements become too large and the circuit board and the like can be reduced in size.
As a result, the size of the device cannot be reduced.

With respect to the chip antenna configured as described above, each part will be described in detail below.

First, the shape of the base 11 will be described.

The base 11 is preferably formed in a prismatic or cylindrical shape. By forming the base 11 in a prismatic shape as shown in FIGS. 1 and 2, the mountability can be improved and the rolling of the element can be improved. And the like. In addition, among the rectangular bases, the base 11 is particularly preferably formed in a square pillar shape, which greatly facilitates the mounting and the positioning of the element on the circuit board. Further, since the base 11 has a prismatic structure, the structure becomes very simple, so that the productivity is good and the cost is very advantageous.

Further, by forming the base 11 into a columnar shape, a conductive film 12 is formed on the base 11 as described later, and a groove 13 is formed in the conductive film 12 by laser processing, grinding, or the like. In this case, the depth and the like of the groove 13 can be formed with high accuracy, and variations in characteristics can be suppressed.

Except for both ends of the base 11, a step portion 11z is formed over the entire circumference, and the groove 13 is provided in the step portion 11z. The step 11z preferably has a depth of 30 to 500 μm. This step 1
By providing 1z, a portion functioning as an antenna can be separated from a circuit board or the like, so that the conductive film 12 is not damaged by contact or the like, and the antenna characteristics do not change. In addition, the circuit board etc. are devised,
Alternatively, when there is very little risk of contact between the spiral conductive film 12 and the substrate by other means, it is not necessary to particularly provide the step portion 11z.

As described above, the cross-sectional shape of both ends of the base 11 is preferably circular or polygonal.
In addition, it is preferable to use a polygonal shape, in particular, a regular polygonal shape, because the characteristics do not change much in any direction. Furthermore, the cross section at the step portion also
Similarly, a circular or polygonal shape is preferable, and in the case of a polygonal shape, a regular polygonal shape is particularly preferable. Note that the cross-sectional shape of the step portion 11z and the cross-sectional shape of both end portions may be different or may be the same.

Next, the chamfering of the base 11 will be described.

The corner formed on the base 11 is chamfered, and the radius of curvature R of the chamfer preferably satisfies the following.

0.1 <R1 <0.5 (mm) If R1 is less than 0.1 mm, the corners of the base 11 are pointed, so that a deposition method such as a plating method or a sputtering method is used. When the conductive film 12 is formed due to, for example, disconnection or peeling at the ridge line portion, the corner portion may be chipped due to a slight impact or the like, and the chipping may cause deterioration of characteristics or the like. Or occur.

If R1 is 0.5 mm or more, sinking or voids may occur in the solder portion when the antenna is mounted on the circuit board, or the solder portion may become thin in the width direction or unsoldered. I do.

Next, the constituent materials of the base 11 will be described. It is preferable to satisfy the following characteristics as a constituent material of the base 11.

Volume resistivity: 10 ¹³ Ωm or more (preferably 10 ¹⁴ Ωm or more) Thermal expansion coefficient: 5 × 10 ⁻⁴ / ° C. or less (preferably 2 × 10 ⁴ / m)
⁻⁵ / ° C. or less) [Coefficient of thermal expansion at 20 ° C. to 500 ° C.] Relative dielectric constant: 40 or less at 1 MHz (preferably 20
Bending strength: 1300 kg / cm ² or more (preferably 20
(00 kg / cm ² or more) Sintering density: 92% or more (preferably 95% or more) of the theoretical density If the constituent material of the base 11 has a volume resistivity of 10 ¹³ Ωm or less, a leakage current between the conductive films 12 This causes loss of antenna gain.

If the coefficient of thermal expansion is 5 × 10 ⁻⁴ / ° C. or more, cracks may occur in the base 11 due to heat shock or the like. That is, when the thermal expansion coefficient is 5 × 10 ⁻⁴ / ° C. or more, the base 11 is locally heated to a high temperature because a laser beam or a grindstone is used when forming the groove 13 as described above. Although cracks and the like may occur in 11, the occurrence of cracks and the like can be greatly suppressed by having the above-described coefficient of thermal expansion.

If the dielectric constant is not less than 40 at 1 MHz, a not-to-negligible capacitance is generated between the conductive films, and the conductive film 12 has a capacitance similar to that when the volume resistivity decreases.
Leakage current occurs between them, causing loss of antenna gain.

When the bending strength is 1300 kg / cm ² or less, the element may be broken when mounted on a circuit board or the like by a mounting apparatus.

If the sintering density is 92% or less of the theoretical density, the water absorption of the base 11 is increased, and the characteristics of the base 11 are remarkably deteriorated. Sufficient mechanical strength cannot be secured due to deterioration or the like.

By defining the volume resistivity, the coefficient of thermal expansion, the dielectric constant, the bending strength, and the sintering density of the base 11 as described above, the antenna gain does not decrease. It is possible to suppress the occurrence of cracks and the like in the base 11 due to heat shock or the like, so that the defect rate can be reduced, and further, the mechanical strength can be improved. Therefore, excellent effects such as an improvement in productivity can be obtained.

As a material for obtaining the above-mentioned various characteristics, a ceramic material containing alumina as a main component can be used. However, simply using a ceramic material mainly composed of alumina cannot obtain the above-mentioned characteristics. That is,
Since the above-mentioned various characteristics vary depending on the pressing pressure, the sintering temperature, and the additives at the time of producing the base 11, the production conditions and the like must be appropriately adjusted. Specific manufacturing conditions include a pressing pressure of 2 to 5 tons when processing the base 11, a firing temperature of 1500 to 1600 ° C., and a firing time of 1 to 3 hours. Specific examples of the alumina material include Al ₂ O ₃ of 92 wt% or more, SiO ₂ of 6 wt% or less, MgO of 1.5 wt% or less, and Fe ₂ O ₃ of 0.1 wt% or less.
% Or less, and Na ₂ O of 0.3% by weight or less.

In addition, forsterite, magnesium titanate and calcium titanate, zirconia / tin / titanium, barium titanate and lead / calcium /
A ceramic material such as a titanium-based ceramic may be used.

The base 11 may be made of a magnetic material such as ferrite.

Next, the surface roughness of the base 11 will be described. The surface roughness described below means the average roughness of the center line, and the roughness described in the description of the conductive film 12 is also the average roughness of the center line.

The surface roughness of the base 11 is preferably 0.1 to 1.0 μm. If the surface roughness is smaller than 0.1 μm, the adhesion strength of the conductive film 12 is reduced, and the surface roughness is larger than 1.0 μm. Then, the conductor loss of the conductive film 12 increases, and the antenna gain decreases.

In the present embodiment, the bonding strength between the conductive film 12 and the base 11 is improved by adjusting the surface roughness of the base 11.
2, carbon alone, carbon with other elements added, C
Improving the adhesion strength between the conductive film 12 and the base 11 without adjusting the surface roughness by providing an intermediate layer composed of at least one of r alone and an alloy of Cr and another metal (NiCr alloy). Can be. Of course, when the surface roughness of the base 11 is adjusted and the intermediate layer and the conductive film 12 are laminated on the base 11, the stronger conductive film 1
The adhesion strength between the base 2 and the base 11 can be obtained.

Next, the conductive film 12 will be described.

Hereinafter, the conductive film 12 will be specifically described.

The constituent materials of the conductive film 12 are copper, silver,
Conductive materials such as gold and nickel can be used. This copper,
Predetermined elements may be added to materials such as silver, gold, and nickel in order to improve weather resistance and the like. Alternatively, an alloy such as a conductive material and a nonmetallic material may be used. Copper and its alloys are often used as constituent materials in terms of cost, corrosion resistance, and ease of fabrication. When copper or the like is used as the material of the conductive film 12, first, a base film is formed on the base 11 by electroless plating, and a predetermined copper film is formed on the base film by electrolytic plating. The conductive film 12 is formed. Further, when the conductive film 12 is formed of an alloy or the like, it is preferable to form the conductive film 12 by a sputtering method or a vapor deposition method.

The conductive film 12 is made of at least one material selected from the group consisting of gold, platinum, palladium, silver, tungsten, titanium, nickel, and tin, or a material selected from the material group and the material group. By configuring at least one of the alloy materials of other elements, it is directly or indirectly joined to the land of the circuit board using, for example, solder or lead-free solder.

The thickness of the conductive film 12 is 1 to 5
If the thickness of the conductive film 12 is smaller than 1 μm, the skin depth required for high-frequency current cannot be sufficiently secured, and if it is larger than 50 μm, the skin depth can be sufficiently secured. Not only loses productivity,
It causes deterioration of environmental resistance performance such as heat shock.

Further, the width K1 of the groove 13 formed in the conductive film 12 and the width K2 of the conductive film 12 between the grooves 13 are determined from the operating frequency, gain, and outer shape of the antenna. It is preferable to have a relationship.

20 μm>K1> 500 μm 5 μm>K2> 500 μm If K1 is 20 μm or less, there occurs a problem that sufficient reliability for insulation between the conductive films 12 cannot be secured.
If it is not less than 00 μm, a problem arises that the inductance value required for the antenna operating frequency cannot be sufficiently obtained.

When K2 is 5 μm or less, conductive film 1
The impedance of the transmission line 2 becomes too high, and impedance matching as an antenna may not be obtained, or the antenna gain may be degraded due to an increase in conductor loss. The required inductance value cannot be obtained sufficiently.

Examples of the method for forming the conductive film 12 include a plating method (such as an electrolytic plating method and an electroless plating method), a sputtering method, and a vapor deposition method. Among these forming methods,
A plating method with good mass productivity and small variations in film thickness is often used.

The surface roughness of the conductive film 12 is preferably 5 μm or less, more preferably 2 μm or less. Conductive film 1
When the surface roughness of No. 2 exceeds 5 μm, a problem occurs that the antenna gain is deteriorated due to an increase in conductor loss.

Next, the protective member 14 will be described.

As the protective material 14, an organic material having excellent weather resistance, for example, an insulating material such as an epoxy resin is used. Further, it is preferable that the protective material 14 has a transparency such that the condition of the groove 13 can be observed. Further, it is preferable that the protective material 14 has a predetermined color while having transparency. By coloring the protective material 14 with a color such as red, blue, or green, which is different from the conductive film 12 and the terminal portions 15 and 16, it is possible to distinguish each element portion, and to easily inspect each element portion. . In addition, by changing the color of the protective material 14 depending on the size, characteristics, product number, and the like of the element, it is possible to reduce errors such as mounting an element having a different characteristic, product number, and the like on an erroneous portion.

The protective material 14 is necessary when weather resistance is required, and when the weather resistance is not required.
It is not necessary to provide. In addition, a protective material 1
4 may be formed, but the protective material 14 may be provided by using an electrodeposition method (for example, a cation electrodeposition method). In this case, a thin and uniform film can be formed. Since it does not penetrate into a large amount, the operating frequency of the chip antenna does not fluctuate or only slightly fluctuates even after the protection member 14 is provided, which is very preferable and excellent in mass productivity.

As the protective material 14, a metal film or the like may be used as shown in FIG. 3, instead of a polymer material such as a resin as described above.

In this case, a metal material having excellent weather resistance is used as the protective material 14, and specific materials of the protective material 14 include gold, platinum, palladium, silver, tungsten, titanium, nickel, and tin. At least one material selected from the group, or an alloy material of an element other than the material selected from the material group and the material group may be used. In particular, from the viewpoint of cost and weather resistance,
Most preferred is gold or gold alloy, tin or tin alloy (excluding tin-lead alloy). The protective material 14 is preferably formed by a plating method using a solution, a sputtering method, an evaporation method, or the like.

The protective material 14 may have a single-layer structure, or may be formed by laminating a material selected from the material group or the alloy material group.

As the formation form of the protective material 14, the conductive film 1
With the configuration in which the entire circumference is almost completely covered with the protective material 14, the conductive film 12 can be reliably protected. First, the conductive film 12 is partially or entirely formed on the base 11, and then the groove 13 is formed, for example, in a spiral shape (so that the winding axis of the remaining spiral conductive film 12 is along the longitudinal direction of the base 11). ), And thereafter, the protective material 14 is formed by the above-described plating method or the like, so that the conductive film 1 is almost completely formed.
2 is covered with the protective material 14.

In this case, the thickness of the protective material 14 is 0.05 μm to 7 μm (preferably 0.1 μm to 5 μm).
μm) is preferable, and if the film thickness is less than 0.05 μm, a problem that sufficient weather resistance cannot be obtained occurs.
If the thickness is larger, there is a possibility that a short circuit may occur between the spiral conductive films 12, or the weather resistance may not be improved so much, and only the cost may increase.

Further, as the protective material 14, preferably,
It is preferable that the electric resistance is small so that the antenna characteristics are not deteriorated.
It is preferable to use gold, gold alloy, platinum, platinum alloy, palladium, palladium alloy, tin, tin alloy (excluding tin-lead alloy).

As the protective material 14, tungsten,
Oxide is formed on the surface of titanium, nickel, etc.
Due to the formation of the oxide, stable weather resistance can be obtained. In this case, the antenna characteristics may vary to some extent over a long period of use. However, depending on the specifications of the antenna to be used, the antenna characteristics can be appropriately used. By forming an oxide on the surface of the protective material 14 and adjusting the characteristics, it is possible to prevent subsequent deterioration of the characteristics.

As described above, by forming the protective material 14 from a metal material having high weather resistance and preferably having a low electric resistance, the characteristics of the protective material 14 can be reduced as compared with a case where a resin or the like is formed as the protective material 14, for example. Variation can be suppressed. That is, when the protective material 14 is formed of a resin or the like, the characteristics are degraded due to variations in the application amount of the resin, or the protective material 14 is formed of the resin, so that it functions as an antenna. Since the insulator is formed relatively thick on the spiral conductive film 12, antenna characteristics are deteriorated. However, as in this embodiment, a metal material having high weather resistance and preferably low electric resistance is used. With this configuration, the amount of the protective material 14 formed on each antenna element can be relatively constant, and a thick insulator is not formed on the spiral conductive film 12. Variations in characteristics and deterioration in antenna characteristics can be prevented.

Further, by using at least one of tin, tin alloy (excluding tin-lead alloy), gold, and gold alloy as the protective material 14 with the above-mentioned materials, it can be directly mounted on a circuit board, and can be used as a lead-free component. Therefore, it is possible to provide an environment-friendly surface mount antenna element.

Next, the terminals 15 and 16 will be described.

Although the terminal portions 15 and 16 function satisfactorily with only the conductive film 12, it is preferable that the terminal portions 15 and 16 have a multilayer structure in order to adapt to various environmental conditions and the like.

The conductive film 12 is formed on the end 11 d of the base 11, and the protective layer 30 made of a weather-resistant material such as nickel or titanium is formed on the conductive film 12.
0 is formed, and a bonding layer 301 made of solder or the like is formed on the protective layer 300. Protective layer 3
00 can improve the bonding strength between the bonding layer 301 and the conductive film 12 and the weather resistance of the conductive film 12. In the present embodiment, at least one of nickel and a nickel alloy is used as a constituent material of the protective layer 300, and solder or lead-free solder is used as a constituent material of the bonding layer 301. The thickness of the protective layer 300 (nickel) is 1 to 8 μm
m is preferable, and when it is less than 1 μm, the weather resistance becomes poor, and
If the thickness exceeds μm, the electric resistance of the protective layer 300 (nickel) itself increases, and the element characteristics are greatly deteriorated. Further, the thickness of the bonding layer 301 (solder) is preferably about 5 μm to 20 μm, and if it is less than 5 μm, the amount of solder is insufficient and good bonding between the element and the circuit board cannot be expected. As the number increases, productivity deteriorates. Note that the protective layer 300 may not be provided when weather resistance is not required.

In order to eliminate the directionality when mounting the chip antenna, the conductive film 12 is formed on all side surfaces of the terminal portions 15 and 16.
Or a bonding layer 301 on the conductive film 12.
Preferably, at least one of the protective layers 300 is provided.

Further, in this embodiment, the conductive film 12 is provided on the entire end face of the base 11, but as shown in FIG. 4 (a), the base 11 is exposed so that the end face of the base 11 is exposed. 11
4B, the conductive film 12 does not exist at all, or as shown in FIG. 4B, the conductive film 12 is not arranged so that the base 11 is exposed at a part of the end surface. By providing the installation portion, the conductive film 12 formed in a spiral shape can be formed into an air-core coil, and the high-frequency magnetic field smoothly flows through the antenna element portion, so that the Q
The value is improved and the antenna gain is improved. The shape of the air-core processing unit (the part where the base 11 is exposed)
In addition to the rectangular shape shown in the figure, a circular shape, an elliptical shape, a triangular shape, a polygonal shape, and the like may be used. There is a problem of not coming.

Further, as the terminal portions 15 and 16, the protective layer 3
When at least one of the base layer 11 and the bonding layer 301 is provided, as described above, the end surface of the base 11 may be exposed, and further, the conductive film 12 is not provided on the end surface of the base 11, A configuration in which at least one of the protective layer 300 and the bonding layer 301 is provided may be adopted. This configuration,
Although the effect of the air core coil is somewhat reduced as compared with the case where the base 11 is exposed, the characteristics can be improved as compared with the case where the conductive film 12 is formed on the entire end face of the base 11.

As the terminal portions 15 and 16, as shown in FIG. 6, a metal cap 400 having a U-shaped cross section and a bottom may be fitted to both ends of the base 11. Metal cap 40
The electric connection with the conductive film 12 is realized by fitting 0. The metal cap 400 may be mounted by press-fitting, or may be mounted by providing a gap between the metal cap 400 and the conductive film 12 and providing a conductive adhesive in the gap. With this configuration, the antenna element can be lifted from the substrate by the thickness of the metal cap 400 on the side surface of the base 11, so that a change in characteristics can be reduced. Also,
As shown in FIG. 6, a bonding film 401 is formed continuously over the metal cap 400 and the conductive film 12 so as to realize electrical bonding between the metal cap 400 and the conductive film 12 in a relatively large area. May be. Bonding film 401
Is formed by a plating method, and is made of a material such as tin, tin alloy (excluding tin-lead alloy), gold, and gold alloy. By using these materials, it can be directly mounted on a substrate and is lead-free. Can be obtained.

Next, the arrangement relationship of the antenna element portion formed of the spiral conductive film will be described.

Basically, the chip antenna according to the present embodiment is formed of the spiral conductive film 12 in order to reduce the change in operating frequency even when one of the terminal portions 15 and 16 is used as a feed portion. As a result of studying the arrangement relationship of the antenna element portion on the chip antenna, it was noted that it is important to satisfy the following relationship.

That is, in FIG. 2, it is essential that the center of the antenna element defined between both ends of the groove 13 exists in the region B in FIG. 2 (the distance between the outermost ends of the groove 13). Is the length of the antenna element).

That is, the total length of the chip antenna is L, and a range of 0.3 × L from both ends (preferably 0.4 × L
And the center in the longitudinal direction of the chip antenna is G, and a range of 0.2 × L (preferably 0.1 × L) is provided at both ends from the center G. L range, more preferably 0.05 × L range), and the length L of the antenna element portion
It was configured such that the center G1 of 1 existed in the range of the B region.

With such a configuration, the terminal portions 15,
Even if any one of the power supply units 16 is used as the power supply unit, there is little difference in operating frequency.

With reference to FIG. 7, a description will be given of the variation of the position where the center of the antenna element portion exists and the operating frequency.

FIG. 7 is a graph showing the deviation of the center of the antenna element from the center of the chip antenna and the variation of the operating frequency of the chip antenna. The horizontal axis indicates the deviation of the center of the antenna element portion from the center of the chip antenna (indicated as a percentage with respect to the total length of the chip antenna), and the vertical axis indicates the amount of variation with respect to the original operating frequency of the chip antenna at 2.41 GHz. Although the variation range of the operating frequency of the antenna which is usually required is within 2%, the graph shows that the variation of the operating frequency of the chip antenna is 2%.
It can be seen that the deviation of the center of the antenna element portion from the center of the chip antenna must be set to at least ± 20% in order to make the ratio within%.

This indicates that the impedance of the chip antenna is increased due to the approach of the high impedance antenna element portion, that is, the spiral conductive film, to the vicinity of the antenna feed portion where the current flows most, and the operating frequency is reduced. On the contrary, when the high-impedance antenna element portion, that is, the spiral conductive film moves away from the antenna feed portion, the impedance of the chip antenna decreases and the operating frequency increases.

Therefore, in order to configure a chip antenna having a small variation in operating frequency regardless of which power supply unit is used, it is necessary to set the antenna in a range of 0.2 × L from the center G in the longitudinal direction of the chip antenna to both ends. It can be seen that the center G1 of the element must be present.

As described above, since the center of the antenna element portion exists in the area B, there is little difference in operating frequency between the left and right terminal portions as the power supply portion. Since there is no need to provide a power supply unit, mountability is greatly improved.

Further, as shown in FIG. 1, both ends of the groove 13 are provided on the same flat side surface 11a as a means for reducing the variation in the operating frequency regardless of which of the terminal portions 15 and 16 is the power supply portion. The number of turns of the spiral conductive film 12 in the antenna element portion is a natural number multiple or a number close to the natural number by configuring the antenna element so as to be on the same ridge line (not shown). Therefore, variations in the operating frequency can be further suppressed.

For example, one end of the groove 13 is connected to the side surface 11a.
And the other end is provided on the surface opposite to the side surface 11a, there is a difference in operating frequency between the case where the terminal portion 15 is the power supply portion and the case where the terminal portion 16 is the power supply portion. Failure occurs.

When the base 11 is cylindrical,
As shown in FIG. 11, a virtual line D2 connecting the ends 13a and 13b of the groove 13 and a center line D along the longitudinal direction of the base 11 are formed.
The number of turns of the antenna element portion can be made a natural number multiple or close to it by configuring the 1s to be parallel or intersect at an angle of ± 5 degrees or less.

A method of manufacturing the chip antenna configured as described above will be described below.

First, the base 11 is manufactured by pressing or extruding an insulating material such as alumina. Next, a conductive film 12 is formed on the entire base 11 by a plating method, a sputtering method, or the like. The conductive film 12 and the base 11
When a buffer layer (carbon film or Ni—Cr film) is provided to increase the adhesion strength between the layers, the buffer layer is provided on the base 11 by a vapor deposition method or a sintering method, and then a conductive layer is formed. The film 12 is formed by a plating method or the like.

Next, a spiral groove 13 is formed in the base 11 on which the conductive film 12 is formed. The groove 13 is formed by laser processing or cutting. Since the laser processing has very high productivity, the laser processing will be described below. First, the base 11 is attached to a rotating device, the base 11 is rotated, and the base 11 is irradiated with a laser to remove both the conductive film 12 and the base 11, thereby forming a spiral groove. Naturally, the groove 13 is formed such that the center of the antenna element portion (the center of the groove 13) is arranged in the region B shown in FIG.
The laser at this time is a YAG laser, an excimer laser,
A carbon dioxide laser or the like can be used, and the base 11 is irradiated with the laser light by narrowing the laser light with a lens or the like. Further, the depth and the like of the groove 13 can be adjusted by adjusting the power of the laser, and the width and the like of the groove 13 can be adjusted by exchanging a lens when narrowing down the laser beam. Since the laser absorptivity varies depending on the constituent material of the conductive film 12 and the like, it is preferable to appropriately select the type of laser (laser wavelength) depending on the constituent material of the conductive film 12.

After the groove 13 is formed, a protective material 14 is applied to the portion where the groove 13 is formed, and is dried or electrodeposited in an electrodeposition liquid to form an electrodeposited resin film and protect the electrode. Lumber 1
4 is formed.

At this point, the product is completed, but a nickel layer or a solder layer may be laminated particularly on the terminal portions 15 and 16 to improve the weather resistance and the joining property. The nickel layer and the solder layer are formed on a semi-finished product on which the protective material 14 is formed by a plating method or the like.

When the protective material 14 is formed of a metal film having high corrosion resistance as shown in FIG. 3, after forming the groove 13, a metal film made of gold, tin, or the like is formed on the conductive film by plating or the like. 12 is formed.

In this embodiment, as the antenna element portion, the conductive film 12 having a spiral shape is used, but a linear body such as a conductive wire may be wound around the side surface of the base. With this configuration, the loss of the conductive wire is smaller than that of the conductive film, so that the antenna gain can be improved.

FIG. 5 is a perspective view of a chip antenna according to an embodiment of the present invention when mounted on a circuit board.
In FIG. 5, reference numeral 100 denotes the chip antenna shown in FIGS. 1 to 3, reference numeral 101 denotes a circuit board, and the circuit board 101 is provided with at least a chip antenna fixing pattern 102 and a pattern 103 connected to a receiving or transmitting circuit. . Although not shown, other electronic components (resistors, capacitors, inductance elements,
At least one of the semiconductor devices) is mounted.

In this embodiment, the terminal portion 16 is joined to the pattern 102 and the terminal portion 15 is joined to the pattern 103, but they may be joined in the opposite direction. Further, in this embodiment, since the cross-sectional shape of the terminal portions 15 and 16 is substantially square, the mounting surface is the side surface 100a. However, even if the mounting surfaces are the side surfaces 100b, 100c, and 100d, the change in characteristics is extremely small. Directivity when mounting the chip antenna 100 can be eliminated.

FIGS. 8 and 9 are a perspective view and a block diagram, respectively, showing a wireless terminal device according to an embodiment of the present invention. 8 and 9, reference numeral 29 denotes a microphone for converting a voice into a voice signal, 30 denotes a speaker for converting a voice signal into a voice, 31 denotes an operation unit including dial buttons and the like, and 32 denotes a display unit for displaying an incoming call and the like. Reference numeral 33 denotes an antenna for exchanging radio waves with a base station connected to a public line or the like, and reference numeral 34 denotes a transmission unit for demodulating an audio signal from the microphone 29 and converting it into a transmission signal. The transmitted signal is emitted to the outside through the antenna 33. 3
A receiving unit 5 converts a received signal received by the antenna 33 into an audio signal. The audio signal created by the receiving unit 35 is converted into audio by the speaker 30. 36 is an antenna,
The antenna 36 exchanges radio waves with a portable terminal device such as a desktop computer or a mobile computer (not shown), and is a chip antenna shown in FIGS. A transmitting unit 37 converts a data signal into a data transmission signal and transmits the data transmission signal via an antenna 36. A receiving unit 38 converts a data reception signal received via the antenna 36 into a data signal. The control unit controls the transmission unit 34, the reception unit 35, the operation unit 31, the display unit 32, the transmission unit 37, and the reception unit 38.

In this embodiment, a helical antenna, a whip antenna or the like is used as the antenna 33, and the antenna 36 is a chip antenna shown in FIGS. And the like.

Further, the antenna 36 and the transmitting unit 3 shown in FIG.
7. A wireless terminal device without the receiving unit 36 and using the antenna 33 as a chip antenna shown in FIGS.

Hereinafter, an example of the operation of the wireless telephone device shown in FIGS. 8 and 9 will be described.

First, when there is an incoming call, the receiving unit 35
Sends an incoming signal to the control unit 39, the control unit 39 displays a predetermined character or the like on the display unit 32 based on the incoming signal, and further presses a button or the like for receiving an incoming call from the operation unit 31. And a signal is sent to the control unit 39,
The control unit 39 sets each unit to the incoming call mode. That is, the signal received by the antenna 33 is converted into an audio signal by the receiving unit 35, the audio signal is output as audio from the speaker 30, and the audio input from the microphone 29 is converted into an audio signal, Through the antenna 33 to the outside.

Next, the case of transmitting a call will be described.

First, when transmitting a signal, a signal to the effect that a signal is transmitted from the operation unit 31 is input to the control unit 39. Subsequently, when a signal corresponding to the telephone number is transmitted from the operation unit 31 to the control unit 39, the control unit 39 transmits a signal corresponding to the telephone number from the antenna 33 via the transmission unit 34. When the transmission signal establishes communication with the other party,
When a signal to that effect is sent to the control unit 39 via the receiving unit 35 via the antenna 33, the control unit 39 sets each unit to the transmission mode. That is, the signal received by the antenna 33 is converted into an audio signal by the receiving unit 35, the audio signal is output as audio from the speaker 30, and the audio input from the microphone 29 is converted into an audio signal, Through the antenna 33 to the outside.

FIG. 10 is a diagram showing a system using a wireless terminal device according to one embodiment of the present invention. In FIG. 10, reference numeral 200 denotes the wireless terminal device shown in FIGS.
Is a mobile terminal device that exchanges data with the wireless terminal device 200, 202 is a base station that communicates with the wireless terminal device 200, and the wireless terminal device 200 communicates directly with the base station 202, and sometimes the earth terminal. It communicates with the base station 202 via the orbiting communication satellites. Reference numeral 203 denotes a server (preferably a communication server) connected to the base station 202 via a public line 204, and the server 203 is connected to an information network 206 such as the Internet via a line 205 such as a public line or a dedicated line. . 207 is information network 2
The user or the like 207 indicates a provider, a specific or unspecified user, or the like.

The mobile terminal device 201 is a
An antenna 201a for exchanging radio waves with 0 is provided. As the antenna 201a, a chip antenna as shown in FIGS. 1 and 2 is preferably used, and the chip antenna is built in the case of the portable terminal device 201. Or provided on a communication card connected to the portable terminal device 201. 201b is the antenna 201
converting the received signal received at a into a received data signal,
Alternatively, the transmission data to be transmitted by the portable terminal device 201 is converted into a transmission signal. 201c is an input means,
The input means 201c includes a keyboard, a handwriting input device, a voice input device, and the like, and inputs data to be sent to the outside. Reference numeral 201d denotes a display means for displaying the transmitted data or displaying data input by the input means 201c. As the display means 201d, a liquid crystal display, a CRT display, an organic EL display, a plasma display, or the like is suitably used. Reference numeral 201e denotes a storage unit for storing transmitted data and the like. The storage unit 201e includes a hard disk drive, a floppy (registered trademark) disk drive, a DVD drive, a magneto-optical disk drive, and a CD-ROM.
An optical disk drive such as an R drive or a CD-RW drive or the like capable of storing and reading data is suitably used. Reference numeral 201f denotes an external storage unit dedicated to reading data, and a read-only drive such as a CD-ROM drive or a DVD-ROM drive is preferably used. 201
g is control means for controlling each part.

Hereinafter, an example of the communication method will be described.

First, the wireless terminal device 200 and the server 20
3 to establish communication.

Data input from the input means 201c of the portable terminal device 201 is transmitted as a transmission data signal to the transmission / reception unit 201b, converted into a transmission signal by the transmission / reception unit 201b, and arranged near via the antenna 201a. (Within a radius of about 10 m) to the wireless terminal device 200.
In the wireless terminal device 200, an antenna 36 not shown
Receives the transmission signal, and is converted into a reception data signal by the reception unit 38. The received data signal is sent to the transmission unit 34 via the control unit 39, and is converted into a transmission signal by the transmission unit 34 and transmitted as a radio wave from the antenna 33.
Information network 206 via base station 202 and server 203
Is transmitted to the user or the like 207 via the mobile terminal device 201.

Further, when data is transmitted from the user or the like 207, the information network 206, the server 203, the base station 202
, A data transmission signal is sent to the wireless terminal device 200. Upon receiving the data transmission signal with the antenna 33, the wireless terminal device 200 receives the data transmission signal with the reception unit 35, and determines whether to convert the received signal into voice. At this time, if the signal is a signal to be converted into an audio signal, a sound is directly output from the speaker 30 and the portable terminal device 2 outputs the data signal.
If it is to be sent to 01, it is sent to the transmission unit 37 via the control unit 39. The transmitting section 37 converts the data signal into a data transmitting signal and transmits the data signal via the antenna 36. When the transmitting signal is received by the antenna 201a, the transmitting / receiving section 201b converts the data signal into a data signal.
In g, a character or the like corresponding to the data signal is displayed on the display means 201d or stored in the storage means 201e.

[0122]

According to the present invention, a base, a pair of terminals provided on the base, a pair of terminals provided on the base and electrically connected to each other and provided between the pair of terminals are provided. A chip antenna having a total length of L, wherein the center of the antenna element portion is 0.4 mm at a central portion excluding a range of 0.3 × L from both end surfaces.
With the provision within the range of × L, the difference in the operating frequency of the antenna can be reduced regardless of which of the pair of terminal portions is the power supply portion, and either terminal portion may be the power supply portion. Sex becomes very good.

[Brief description of the drawings]

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

FIG. 2 is a side sectional view showing a chip antenna according to an embodiment of the present invention.

FIG. 3 is a side sectional view showing a chip antenna according to another embodiment of the present invention.

FIG. 4 is a side view of a terminal portion showing a chip antenna according to an embodiment of the present invention.

FIG. 5 is a perspective view showing the mounting of the chip antenna of the present invention on a circuit board.

FIG. 6 is a side sectional view showing a chip antenna according to another embodiment of the present invention.

FIG. 7 is a graph illustrating the position where the center of the antenna element portion exists and the operating frequency;

FIG. 8 is a perspective view showing a wireless terminal device according to one embodiment of the present invention;

FIG. 9 is a block diagram illustrating a wireless terminal device according to an embodiment of the present invention.

FIG. 10 is a diagram showing a system using a wireless terminal device according to one embodiment of the present invention;

FIG. 11 is a plan view showing an end surface of a chip antenna according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Base 11z Step part 12 Conductive film 13 Groove 14 Protective material 15, 16 Terminal part 30 Speaker 31 Operation part 32 Display part 33, 36 Antenna 34, 37 Transmission part 35, 38 Receiving part 39 Control part 200 Wireless terminal device 201 Mobile Terminal device 202 Base station 203 Server 204 Public line 205 Line 206 Information network 207 User etc.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Katsumi Sasaki, Inventor 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. In-house F term (reference) 5E070 AA01 AB03 CB01 CC03 EA01 5J046 AA04 AA09 AB12 PA06 5J047 AA04 AA09 AB12 FD01

Claims (21)

[Claims] 1. A base, a pair of terminals provided on the base, and electrically connected to the pair of terminals provided on the base and provided between the pair of terminals. A chip antenna having a total length of L, wherein the center of the antenna element portion is 0.4 mm at a central portion excluding a range of 0.3 × L from both end surfaces. A chip antenna provided in a range of × L. 2. The chip antenna according to claim 1, wherein the antenna element portion is formed of a spiral conductive film formed over the entire side surface of the base. 3. A spiral conductive film is formed by providing a conductive film all around the side surface of the base and forming a spiral groove in the conductive film all around the side surface. Item 3. The chip antenna according to Item 2. 4. The chip antenna according to claim 2, wherein a protective material made of a metal film having high corrosion resistance is provided on the surface of the conductive film. 5. The metal film is made of at least one material selected from the group consisting of gold, platinum, palladium, silver, tungsten, titanium, nickel, and tin, or a material selected from the material group and a material other than the material group. 5. The chip antenna according to claim 4, wherein the chip antenna is formed of at least one of alloy materials of the following elements. 6. The chip antenna according to claim 2, wherein an electrodeposition resin film formed by an electrodeposition method is provided on a surface of the conductive film. 7. The chip antenna according to claim 2, wherein a buffer layer is provided between the conductive film and the base. 8. A carbon film, a carbon-containing film,
The chip antenna according to claim 7, wherein at least one of a Ni alloy film is provided. 9. The conductive film itself is made of gold, platinum, palladium, silver,
It is characterized by comprising at least one material selected from the group consisting of tungsten, titanium, nickel and tin, or at least one of a material selected from the material group and an alloy material of an element other than the material group. The chip antenna according to claim 2. 10. The chip antenna according to claim 3, wherein the number of turns of the spiral groove is a natural number times. 11. The chip antenna according to claim 3, wherein the base has a prismatic shape, and both ends of the groove are arranged on the same side surface or on the same ridge line. 12. The base according to claim 3, wherein the imaginary line connecting both ends of the groove is substantially parallel to the central axis along substantially the entire length (intersection angle is ± 5 degrees). The described chip antenna. 13. The chip antenna according to claim 1, wherein a linear conductor wire is spirally wound around a side surface of the base as the antenna element portion. 14. The chip antenna according to claim 1, wherein terminal portions are provided on all side surfaces at both ends of the base. 15. The semiconductor device according to claim 14, wherein at least one of a protective layer and a bonding layer is provided on the conductive film as a terminal portion.
The described chip antenna. 16. The chip antenna according to claim 1, wherein the terminal portion is formed by fitting caps made of a conductive material to both ends of the base. 17. The chip antenna according to claim 16, wherein a bonding film is provided over the cap and the antenna element portion. 18. The chip antenna according to claim 17, wherein at least one of tin, tin alloy (excluding tin-lead alloy), gold, and gold alloy is provided as the bonding film. 19. A signal conversion means for converting a voice into a voice signal or data into a data signal, an operation means for inputting a telephone number or the like, a display means for displaying an incoming call display or a telephone number, etc., 2. A transmitting means for modulating a data signal to convert it into a transmission signal, a receiving means for converting a received signal into a voice or data signal, and at least one of transmitting and receiving said transmission signal or said received signal.
A wireless terminal device comprising: the antenna according to any one of (1) to (18); and control means for controlling each unit. 20. A first system for transmitting / receiving a signal to / from a base station.
An antenna, a first transmitting / receiving unit for converting a signal transmitted / received by the first antenna into a data signal, a second antenna for transmitting / receiving a signal to / from a portable terminal device provided in the vicinity, 19. The antenna according to claim 1, further comprising a second transmitting / receiving unit configured to convert a signal transmitted / received by the second antenna into a data signal, wherein at least one of the first antenna and the second antenna is used. A wireless terminal device having a structure. 21. A base station for exchanging data or a voice signal between the wireless terminal device, a portable terminal device for transmitting / receiving data to / from the wireless terminal device, and a wireless terminal device. Station, a server connected to the base station by a public line, an information network connected to the server via a line 205, a specific or unspecified user or a user having a provider connected to the information network, etc. A data transmission / reception system having: