JPH10290175A - Antenna structure for small sized radio equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an antenna from being damaged by incorporating a chip antenna to a small sized radio equipment and to enhance the miniaturization and the antenna performance of the radio equipment main body sufficiently even when the chip antenna is built in. SOLUTION: In the antenna structure for a small sized radio equipment 10 provided with a chip antenna 13 that transmits/receives a signal and with a radio printed circuit board 12 on which circuit components required for radio communication are mounted, the chip antenna 13 is mounted on an antenna board formed separately from the radio printed circuit board 12 and the antenna board 14 is placed in the small sized radio equipment 10 in a state that the board 14 is nearly orthogonal to the radio printed circuit board 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna structure for a small wireless device such as a portable telephone or a PC card.

[0002]

2. Description of the Related Art In recent years, portable telephones and PC cards having a wireless communication function have been widely used as small wireless devices for performing wireless communication. Note that a PC card having a wireless communication function is PCMCIA (personal computer memory c).
ard international association) is installed in an interface slot to provide a mobile computing environment.

Incidentally, these portable telephones and PC cards usually have an antenna structure protruding from a main body, such as a helical antenna or a whip antenna. For example, a PC card has a rotatable external antenna 20 as shown in FIG. 7, and the external antenna 20 is housed during wireless communication (see FIG. 7A).
There is a configuration in which a predetermined level of reception sensitivity is ensured by turning the sensor from the first position to a projected state (see FIG. 7B).

[0004]

However, in the above-described antenna structure of the small wireless device, the external antenna 20 is protruded during wireless communication, so that an external impact such as a drop of the small wireless device itself is applied. If
The external antenna 20 and its peripheral components may be damaged. Further, since this antenna structure requires the external antenna 20 and its rotating mechanism, a large occupied area is required, and it is difficult to reduce the size of the wireless device main body.

[0005] For this purpose, it is conceivable to incorporate an antenna chipped by a semiconductor element (hereinafter referred to as a chip antenna) into the main body of the radio, but in this case,
The chip antenna must be mounted on an electronic board incorporated in the wireless device. In other words, the chip antenna
Since it is mounted on the same plane (on the same electronic board) as other circuit components required for wireless communication (such as a modulator and an amplifier), the size of the electronic board in the wireless device itself increases, As a result, it becomes difficult to reduce the size of the wireless device itself.

Further, a chip antenna usually has a directivity of radiating radio waves in a direction parallel to a mounting surface of the chip antenna, but when the chip antenna is mounted on another circuit component on the same substrate, However, there is a possibility that the radiated radio wave is affected by reflection or absorption by other circuit components, and as a result, its performance cannot be sufficiently exhibited.

Therefore, the present invention prevents the antenna from being damaged by incorporating the chip antenna, and also enables the miniaturization of the radio unit itself and the full performance of the antenna even if the chip antenna is incorporated. It is an object of the present invention to provide an antenna structure of a small wireless device.

[0008]

SUMMARY OF THE INVENTION The present invention is an antenna structure of a small radio set devised to achieve the above object. That is, the present invention is an antenna structure of a small wireless device including a chip antenna for transmitting and receiving signals by wireless radio waves, and a wireless board mounted with circuit components necessary for wireless communication using the chip antenna, The chip antenna is mounted on an antenna board formed separately from the wireless board, and the antenna board is disposed in the small wireless device so as to be substantially orthogonal to the wireless board. Is what you do.

According to the antenna structure having the above-described structure, signals are transmitted and received by wireless radio waves using the chip antenna, so that it is not necessary to project an external antenna or the like from the small wireless device during wireless communication. In addition, the antenna board on which the chip antenna is mounted and the wireless board on which circuit components necessary for wireless communication are mounted are separated from each other, and are arranged so as to be substantially orthogonal to each other. Can be used effectively. Furthermore, since the antenna board and the wireless board are arranged so as to be substantially orthogonal, even if the chip antenna has directivity, the radiated wireless wave may be affected by other components on the wireless board. There is no.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an antenna structure of a small radio device according to the present invention will be described with reference to the drawings. However, here, a case where the small wireless device is a PC card, that is, a case where the antenna structure of the present invention is applied to a PC card will be described as an example.

[First Embodiment] FIG. 1 shows an antenna structure of a PC card 10 according to the present embodiment. In the present embodiment, the PC card 10 is configured as shown in FIG. See Figure 1
As shown in (b), the PC card 10 is
, A wireless board 12, a chip antenna 13, an antenna board 14, and shield cases 15 and 16.

The control board 11 is for controlling wireless communication by the PC card 10, and has a CPU (Central
Peripheral components such as Processing Unit) and ROM (Read Only Memory), general-purpose LSI such as modem and voice codec
(Large Scale Integration), a channel codec, a custom LSI such as a card interface, and a power control unit. The wireless board 12
Signal processing necessary for wireless communication is performed according to control by the control board 11. For this purpose, circuit components such as a signal modulator and an amplifier are mounted on the wireless board 12. The wireless board 12 has a coaxial cable 1 to be described later.
A coaxial connector 12a for 4a is provided. The control board 11 and the wireless board 12 are
are electrically connected via a. The control board 1
1 and the wireless board 12 may be provided integrally.

The chip antenna 13 transmits a signal processed by the wireless board 12 to a communication partner by radio waves, or receives a signal transmitted wirelessly from the communication partner and sends the signal to the wireless board 12. is there. That is,
The chip antenna 13 is for transmitting and receiving signals by radio waves. However, the chip antenna has a directivity of emitting a radio wave in a direction parallel to the mounting surface. The antenna substrate 14 is a substrate on which the chip antenna 13 is mounted. However, the antenna substrate 14
Are formed separately from the wireless board 12, and are electrically connected to the wireless board 12 via the coaxial cable 14a.

The shield case 15 is integrally formed of a resin material or the like, and has its surface plated with chrome or the like, and is formed so as to cover the upper surface of the wireless board 12. In the vicinity of both ends of one side surface of the shield case 15, an engagement portion 15a having a U-shaped cross section is provided. Similarly to the shield case 15, the shield case 16 is integrally formed of a resin material or the like, and the surface thereof is plated, and is formed so as to cover the lower surface of the wireless board 12. The shield case 16 also has engaging portions 16 near both ends on one side surface thereof.
a is provided.

A PC card 10 having these components
In FIG. 1, as shown in FIG. 1A, a wireless board 12, a chip antenna 13, an antenna board 14, and shield cases 15, 16 are housed in an extended portion 10a, and a wireless unit is configured by these. I have. The extended section 10a is a PCMCI
The extended type PC card provided in A, which is a portion protruding from the card slot when the PC card is inserted into the card slot.

In the extended portion 10a, the upper surface of the wireless substrate 12 is covered with the shield case 15, and the lower surface is
Covered in. At this time, each shield case 15, 1
The antenna substrate 14 is locked to the engaging portions 15a and 16a of the sixth. That is, each engagement portion 15a,
Both ends of the antenna substrate 14 are engaged with the grooves formed by 16a. Thus, the antenna substrate 14 is fixed by the shield cases 15 and 16 in a state substantially orthogonal to the wireless substrate 12. For example, if the wireless board 12 is arranged in the horizontal direction, the antenna board 14 is fixed in the vertical direction.

The engagement between the antenna board 14 and each of the shield cases 15 and 16 allows them to be grounded (connected to ground). Therefore, when the shield cases 15 and 16 cover the wireless board 12, the antenna board 14 and the wireless board 12
They will be shielded from each other.

In this PC card 10, an antenna board fixed so that the wireless board 12 covered by the shield cases 15 and 16 and the mounting surface of the chip antenna 13 face the outside (the direction in which the PC card 10 is removed). 14 is connected by a coaxial cable 14a, so that the chip antenna 13 can transmit and receive signals by radio waves.

As described above, according to the antenna structure of the PC card 10 of the present embodiment, since signals are transmitted and received by the built-in chip antenna 13, there is an external impact such as a drop of the PC card 10. Even in this case, the possibility of breakage and the like is reduced as compared with the case where the antenna is protruded. Further, since the wireless board 12 and the antenna board 14 are provided separately and are disposed so as to be substantially orthogonal to each other, the space (capacity) in the extended portion 10a can be effectively used, Chip antenna 13
Is mounted on the same board as other circuit components.
The size of the wireless unit can be easily reduced. Furthermore, since the wireless board 12 and the antenna board 14 are disposed so as to be substantially orthogonal to each other, the chip antenna 1 on the antenna board 14
Even if 3 has directivity, the radiated radio wave is not affected by other circuit components on the radio board 12 (such as reflection and absorption), and the radiation characteristics of the chip antenna 13 are improved. The antenna performance can be fully exhibited.

In the antenna structure of the PC card 10 of the present embodiment, the radio board 12 is covered by the shield cases 15 and 16 to shield the radio board 12 and the antenna board 14. Therefore, the chip antenna 13 on the antenna substrate 14 is less likely to receive noise or the like from other circuit components on the wireless substrate 12, and further improvement in the radiation characteristics of the chip antenna 13 can be expected.

In the antenna structure of the PC card 10 according to the present embodiment, the engaging portions 1 are
5a and 16a are provided by integral molding.
The antenna substrate 14 and the shield cases 15 and 16 are locked by utilizing a and 16a. That is, the engaging portions 15 provided on the shield cases 15 and 16 are provided.
The antenna substrate 14 is fixed by a and 16a. Therefore, the structure for fixing the antenna board 14 can be simplified, the size of the wireless unit can be further reduced, and the cost can be reduced by reducing the number of parts and the number of assembly steps.

[Second Embodiment] Next, an antenna structure according to a second embodiment of the present invention will be described.
The PC card according to the present embodiment includes, in addition to the first embodiment described above, a fixed metal plate 17 formed in a leaf spring shape as shown in FIG. Recesses 15b, 16b into which the ends of the fixed sheet metal 17 are fitted are respectively fitted to the shield cases 15, 16.
Shall be provided.

In this embodiment, as in the first embodiment, the upper surface of the wireless board 12 is covered with the shield case 15 and the lower surface is covered with the shield case 16. However, in the present embodiment, FIG.
As shown in (b), the ends of the fixed sheet metal 17 are fitted into the concave portions 15b, 16b of the shield cases 15, 16, so that the shield cases 15, 16 are connected. .

Further, in the present embodiment, as shown in FIG. 2C, the elasticity of the fixing metal plate 17 causes the antenna substrate 14 to engage with the engaging portions 15 of the shield cases 15 and 16.
When the chip antenna 13 is engaged with the chip antenna 13, the chip antenna 13 is urged toward the mounting surface. A ground terminal (earth pattern) is provided in the vicinity of both sides of the antenna substrate 14 on the chip antenna 13 mounting surface side or at a location corresponding to the fixed metal plate 17 on the chip antenna 13 non-mounting surface side. Assume that the engagement between the substrate 14 and each of the shield cases 15 and 16 grounds each other.

That is, according to the antenna structure of the PC card of the present embodiment, each of the shield cases 15 and 16 is connected by the fixing plate 17 and
Due to the elasticity of the antenna 7, the antenna substrate 14 is urged toward the mounting surface of the chip antenna 13. Thereby, the antenna substrate 14 and the shield cases 15, 1
6 can be securely fixed without generating backlash or the like. In addition, the fixing metal plate 17 is
By energizing 4, the grounding of the antenna substrate 14 and each of the shield cases 15 and 16 is ensured, and the shielding effect of the shield cases 15 and 16 is improved. Therefore, the radiation characteristics of the chip antenna 13 on the antenna substrate 14 are further improved.

[Third Embodiment] Next, an antenna structure according to a third embodiment of the present invention will be described.
In the present embodiment, unlike the first and second embodiments described above, the engaging portions 15a,
16a is not provided, and as shown in FIG.
On the side of the antenna substrate 14 where the chip antenna 13 is not mounted,
An engaging portion 14b is provided.

The engaging portion 14b is formed in a chip antenna of the antenna substrate 14 in a state in which a side surface shape is formed substantially in a U-shape and a conductive leaf spring member is opposed so as to form a pair in the vertical direction. 13 is mounted on the non-mounting surface side by soldering or the like. The mounting of the engaging portion 14b is performed by S
What is necessary is just to use the reflow soldering method which is the mainstream of MT (Surface Mount Technology) mounting.

By providing such an engaging portion 14b, in this embodiment, as shown in FIG. 3B, each shield case 15, 1
The engaging portions 14b are fitted into the recesses 15b, 16b of the sixth. Thereby, each shield case 1
5 and 16 are connected, and the antenna substrate 14 and each of the shield cases 15 and 16 are grounded via the engaging portion 14b.

Therefore, according to the antenna structure of the PC card of the present embodiment, the engaging portion 14 made of a leaf spring member is used.
b, the antenna substrate 14 and the shield cases 15, 1
6 and the grounding between them is performed, so that the antenna substrate 1 is provided in the same manner as in the second embodiment.
4 and the shield cases 15 and 16 can be securely fixed, and the shield effect by the shield cases 15 and 16 can be improved.

Moreover, in the present embodiment, it is not necessary to provide the engaging portions 15a, 16a on the shield cases 15, 16, so that the shapes of the shield cases 15, 16 can be simplified. In addition, the mounting of the engaging portion 14b to the antenna substrate 14 can be performed [automatic mounting → reflow soldering]. Therefore, the number of mounting steps or the number of assembling steps can be further reduced.

[Fourth Embodiment] An antenna structure according to a fourth embodiment of the present invention will now be described.
In the present embodiment, as in the third embodiment described above, as shown in FIG. 4A, a conductive leaf spring member is provided on the side of the antenna substrate 14 on which the chip antenna 13 is not mounted. The engaging portion 14c is provided by soldering or the like. However, unlike the engaging portion 14b according to the third embodiment, the engaging portion 14c is
In order to fit with b, the side surface shape is formed in a substantially C-shape.

That is, in the antenna structure of the PC card according to the present embodiment, as shown in FIG. 4B, the engagement portion 14c is provided on the antenna substrate 14, and the antenna portion 14c is provided by the engagement portion 14c. 14 is locked to the wireless board 12. Therefore, for example, a circuit component is mounted only on one surface of the wireless board 12.
Even if one (or both) of the shield cases 15 and 16 becomes unnecessary, the antenna substrate 14
Can be reliably fixed. That is, even if there is a change in the shield structure, it is possible to easily cope with the change.

Further, as shown in FIG.
4c is used for power supply, and the wireless substrate 12 and the antenna substrate 1 are connected via the power supply engaging portion 14c.
If the configuration is such that electrical connection with the cable 4 is made, the coaxial cable 14a can be omitted, and further downsizing and cost reduction can be achieved by simplifying the component configuration.

[Fifth Embodiment] Next, an antenna structure according to a fifth embodiment of the present invention will be described.
In the present embodiment, as shown in FIG. 5A, the wireless unit includes a wireless board 12, a chip antenna 13, an antenna board 14, shield cases 15, 16 and a fixed metal plate 18. I have. Among these, the fixed sheet metal 18 has a substantially U-shaped side surface and is made of a conductive leaf spring member. The shield cases 15 and 16 are provided with the engaging portions 15a and 16a and the concave portion 1 respectively.
5b and 16b may not be provided. It is assumed that the antenna substrate 14 does not have the engaging portions 14b and 14c mounted thereon.

Also in the present embodiment, the above-mentioned first to first embodiments are described.
Similarly to the fourth embodiment, the upper surface of the wireless board 12 is covered with the shield case 15 and the lower surface is covered with the shield case 16. However, in this embodiment,
As shown in FIG. 5B, the fixed metal plate 18 uses its elasticity to make the wireless board 12 and the shield cases 15 and 16 different from each other.
And the antenna substrate 14 is gripped on one side surface of the shield cases 15 and 16. That is, since the fixing sheet metal 18 functions as the engaging portion in the present invention, the antenna substrate 14 and the shield cases 15 and 16 are securely fixed without any play or the like.

Therefore, according to the antenna structure of the PC card of the present embodiment, the fixing plate 18 can be mounted on the antenna substrate without the need for the engaging portions 14b, 14c, the engaging portions 15a, 16a, or the concave portions 15b, 16b. Since the antenna substrate 14 and the shield cases 15 and 16 can be fixed only by mounting the antenna case 14 from the outside (on the chip antenna 13 mounting surface side), the shapes and component configurations of the shield cases 15 and 16 are simplified. And further reduction in size and cost can be achieved.

Further, in the present embodiment, the fixed sheet metal 18
Mounting the antenna substrate 14 and the shield case 1
Since the antenna substrates 14 and 15 are fixed, the antenna substrate 14 can be fixed to any side surface of the shield cases 15 and 16. For example, as shown in FIG. 5C, even when the fixed position (fixed surface) of the antenna substrate 14 is changed, it is possible to easily cope with this.

[Sixth Embodiment] Next, an antenna structure according to a sixth embodiment of the present invention will be described.
In the present embodiment, unlike the first embodiment, the wireless unit is configured as shown in FIG. More specifically, the shield cases 15 and 16 are not formed by plating a resin material or the like that is integrally molded, but by a metal plate that has been subjected to sheet metal processing. Further, on the upper surface or near the lower surface of each of the shield cases 15 and 16, engaging portions 15a, 1
6a is provided.

Also in the present embodiment, the above-described first to first embodiments
Similarly to the fifth embodiment, the upper surface of the wireless board 12 is covered with the shield case 15 and the lower surface is covered with the shield case 16. However, in this embodiment,
It is assumed that the shield cases 15 and 16 are fixed on the wireless board 12 by soldering or the like so that a shield effect is obtained.

In this embodiment, as shown in FIG. 6 (b), the claw-shaped engaging portions 15a, 16a provided on the shield cases 15, 16 are attached to the upper and lower edge portions of the antenna substrate 14, respectively. Are engaged. That is, the antenna board 14
Utilizing the elasticity of the engaging portions 15a and 16a, the shield cases 15 and 16 are securely fixed to one side surface without any play or the like. At this time, each shield case 1 is located near the upper and lower edges of the antenna substrate 14.
If a ground terminal is provided at a position corresponding to the engaging portions 15a and 16a of the antennas 5 and 16, the fixing of the antenna substrate 14 and the shielding case 1
Grounding between 5 and 16 is performed simultaneously.

Therefore, according to the antenna structure of the PC card of the present embodiment, the claw-shaped engaging portions 15a, 16a provided on the shield cases 15, 16 ensure that the antenna substrate 14 is securely fixed, The effect is improved. Moreover, in the present embodiment, the fixed sheet metal 1
Since the components 7 and 18 are not required, the component configuration can be simplified while realizing the secure fixing of the antenna substrate 14 and the improvement of the shielding effect.

In the first to sixth embodiments described above, the case where the antenna structure of the present invention is applied to a PC card has been described as an example, but the present invention is not limited to this. . For example, other than a PC card, the present invention is applicable to any small wireless device that performs communication by radio waves, such as a mobile phone.

[0043]

As described above, in the antenna structure of the small radio device according to the present invention, signals are transmitted and received by the built-in chip antenna. The possibility of breakage and the like is reduced as compared with the case where the projection is performed. In addition, since the chip antenna is mounted on an antenna substrate separate from the wireless substrate, and these are arranged so as to be substantially orthogonal to each other, the space in the small wireless device can be effectively utilized, and the chip antenna can be effectively used. Can be easily reduced in size as compared with a case in which is mounted on the same substrate as other circuit components. Furthermore, since the wireless board and the antenna board are arranged so as to be substantially orthogonal to each other, even if the chip antenna has directivity, the radiated radio wave does not affect other circuit components on the wireless board. Therefore, the radiation characteristics of the chip antenna 13 are improved, and the antenna performance can be sufficiently exhibited.

[Brief description of the drawings]

FIG. 1 is a first view of an antenna structure of a small wireless device according to the present invention.
1A is a schematic perspective view of the embodiment, and FIG. 1B is an exploded perspective view of the embodiment.

FIG. 2 is a second view of the antenna structure of the small wireless device according to the present invention;
3A is an exploded perspective view, FIG. 3B is a perspective view showing a main part thereof (part 1), and FIG.
FIG. 4 is a perspective view (part 2) showing a main part thereof.

FIG. 3 is a third view of the antenna structure of the small wireless device according to the present invention;
1A is an exploded perspective view of the embodiment, and FIG. 1B is a perspective view of an essential part thereof.

FIG. 4 is a fourth view of the antenna structure of the small wireless device according to the present invention;
3A is an exploded perspective view, FIG. 3B is a perspective view showing a main part thereof (part 1), and FIG.
FIG. 4 is a perspective view (part 2) showing a main part thereof.

FIG. 5 is a fifth view of the antenna structure of the small wireless device according to the present invention;
3A is an exploded perspective view, FIG. 3B is a perspective view showing a main part thereof (part 1), and FIG.
FIG. 4 is a perspective view (part 2) showing a main part thereof.

FIG. 6 shows a sixth antenna structure of the small radio device according to the present invention.
1A is an exploded perspective view of the embodiment, and FIG. 1B is a perspective view of an essential part thereof.

7A and 7B are perspective views showing an antenna structure of a conventional PC card, wherein FIG. 7A is a diagram showing a stored state of an external antenna, and FIG. 7B is a diagram showing a protruding state of the external antenna.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 PC card 12 Wireless board 13 Chip antenna 14 Antenna board 14a Coaxial cable 14b, 14c, 15a, 16a Engagement part 15, 16 Shield case 17, 18 Fixed metal plate

Claims (4)

[Claims] 1. An antenna structure for a small wireless device, comprising: a chip antenna for transmitting and receiving signals by radio waves; and a wireless board on which circuit components necessary for wireless communication using the chip antenna are mounted. The chip antenna is mounted on an antenna substrate formed separately from the wireless substrate, and the antenna substrate is disposed in the small wireless device so as to be substantially orthogonal to the wireless substrate. Antenna structure of small radio. 2. The antenna structure for a small wireless device according to claim 1, wherein a shield case for covering the wireless substrate and the antenna substrate is provided by covering the wireless substrate. 3. The antenna board is provided on one or both of the antenna board and the shield case,
3. The antenna structure for a small wireless device according to claim 2, wherein an engagement portion is provided for engaging the shield case or the wireless board. 4. When the antenna substrate and the shield case are electrically grounded by the engagement portion,
4. An antenna structure for a small wireless device according to claim 3, further comprising an urging means for urging said antenna substrate in a predetermined direction.