JPH09135120A - Antenna system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive antenna system with simple configuration capable of obtaining an improved diversity effect even when a portable telephone set is made small sized. SOLUTION: This antenna system incorporates a radio communication circuit substrate 2, is arranged in the case 1 of the portable radio telephone set 20 having a receiver 9 at a one side part of its tip part and is provided with a whip antenna 3 which is arranged to be housed in the case 1 and an incorporated antenna which is housed in the case 1. Then, the incorporated antenna is constituted of a helical antenna 7 and the helical antenna 7 is made to be apart from the arrangement position of the whip antenna 3 and to be arranged at a position opposing the receiver 9 of the case 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna device of a mobile phone for diversity reception, and particularly when the housing of the mobile phone is miniaturized, the effect of human hands or the like can be reduced to achieve a good diversity effect. The present invention relates to an antenna device capable of obtaining.

[0002]

2. Description of the Related Art Conventionally, as an antenna device for a mobile phone, a device using an inverted F antenna as disclosed in Japanese Patent Publication No. 63-8655 has been proposed. This Japanese Examined Patent Publication No. 63-8655 discloses a configuration in which the inverted F antenna is arranged on the upper rear surface of the housing in order to reduce the influence of the human body on the inverted F antenna when using the mobile phone.

FIG. 6 shows an example of an antenna device of a mobile phone capable of performing diversity reception using the inverted F antenna disclosed in Japanese Patent Publication No. 63-8655. Is configured by providing a whip antenna 3 as an external antenna and an inverted F antenna 4 as a built-in antenna on a substrate 2 in a housing 1. Here, the inverted F antenna 4 is used when using this mobile phone. In order to reduce the influence of the human head 5 on the inverted F antenna 4, it is provided on the upper rear surface of the housing 1.

However, in the antenna device of the mobile phone, when the housing 1 becomes small, as shown in FIG.
When a person holds the housing 1, a part of the inverted F antenna 4 may be covered with the hand 6, and in this case, the presence of the hand 6 causes the antenna to be misaligned and shields radiation. This causes a problem that the antenna characteristics of the F antenna 4 are significantly deteriorated.

Incidentally, in the configuration shown in FIG. 6, the length of the casing 1 of the portable telephone is 120 mm, and the average value of the antenna gain when only the human head 5 is in contact with the casing 1 of this portable telephone is shown. If 0 dB, the average value of the antenna gain when the human head 5 and the hand 6 are in contact with the housing 1 of this mobile phone becomes −3 dB, and the position of the hand 6 is further moved to the upper part of the housing 1 of the mobile phone. Experimental results have been obtained that the average value of the antenna gain in the case of being set is −6 dB, and the average value of the antenna gain in the case of covering the inverted F antenna 4 with the hand 6 is −10 dB.

[0006] Japanese Patent Publication No. 63-8655 also discloses a configuration in which an inverted F antenna is arranged on the top of the casing of a mobile phone, and diversity reception can be performed using this inverted F antenna. Although such a configuration is also conceivable, in this case, the human head comes very close to the inverted F antenna when the human being holds the mobile phone. Due to the existence of the antenna, the matching of the antenna is deviated and the antenna characteristic of the inverted F antenna is deteriorated.

Further, as shown in FIG. 8 (a), the inverted F antenna has a fixed base 12 disposed between the inverted F antenna 4 and the substrate 2, and also has a short-circuit portion 10 and a power feeding portion 11.
Or a dielectric block 13 is provided between the inverted F antenna 4 and the substrate 2 as shown in FIG. 8B.
And a short circuit portion 10 and a power feeding portion 11 are provided. The structure is complicated, the number of assembling steps is large, and the cost is high.

[0008]

As described above, in the antenna device of the mobile phone for performing diversity reception using the conventional inverted F antenna, when the housing of the mobile phone is miniaturized, the human hand or the human head. Due to the influence of the parts, there is a problem that the matching of the antenna is deviated and the antenna characteristics of the antenna are significantly deteriorated. Further, when the inverted F antenna is used, its structure is complicated, the number of assembling steps is large, and the cost is high. was there.

Therefore, an object of the present invention is to provide an antenna device which can obtain a good diversity effect even when the housing of a mobile phone is downsized, and has a simple structure and a low cost. .

[0010]

In order to achieve the above object, the present invention is provided in a casing of a portable radio telephone having a wireless communication circuit board and a receiver on one side of the top thereof. In an antenna device comprising a whip antenna housed in the housing and a built-in antenna housed in the housing, the built-in antenna is composed of a helical antenna, and the helical antenna is arranged in the whip antenna. It is characterized in that it is arranged at a position separated from the installed position and facing the receiver of the casing.

Here, the helical antenna has a rising portion, and is connected to the wireless communication circuit board via the rising portion.

The helical antenna is arranged so that its axial direction is parallel to the whip antenna.

Further, the helical antenna is arranged so that its axial direction is perpendicular to the whip antenna and perpendicular to the surface of the wireless communication circuit board.

The helical antenna is arranged so that its axial direction is perpendicular to the whip antenna and parallel to the surface of the wireless communication circuit board.

Further, the wireless communication circuit board has a cutout portion, and the helical antenna is arranged in the cutout portion.

According to the present invention, in a mobile phone for diversity reception, a helical antenna is used as the built-in antenna so that the built-in antenna is provided at a position facing the receiver provided at the top of the housing of the mobile phone. You can In this case, the built-in antenna is located at the position farthest from the human hand or head when a person holds the mobile phone casing by hand to make a call, which results in the antenna characteristics of the built-in antenna. The deterioration of can be reduced to the minimum value.

Then, this becomes remarkable as the size of the casing of the mobile phone is reduced.

Further, according to the present invention, since the rising portion is provided between the helical antenna and the radio communication circuit board built in the housing of the mobile phone, the characteristics of the helical antenna, which is an internal antenna, in a free space are provided. Can also be improved.

Further, in the antenna device according to the present invention, since the power feeding portion can be constructed only by connecting it to the substrate, the number of assembling steps can be reduced and the cost can be reduced.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a first antenna device according to the present invention.
FIG. 2 is a side view of the embodiment of FIG. 2, and FIG. 2 is an enlarged front view of the main part thereof.

In FIG. 1 and FIG. 2, the antenna device has a wireless communication circuit board 2 built-in and is arranged in a housing 1 of a portable wireless telephone 20 having a receiver 9 on one side of the top thereof. At one end of the upper part of the substrate 2, a whip antenna 3 which is erected from the housing 1 so as to extend and contract and is connected to the substrate 2 is arranged, and at the other end of the upper part of the substrate 2, a helical start-up part 8 A spiral helical antenna 7, which is an internal antenna, is connected to the substrate 2 via.

Here, the arrangement position of the helical antenna 7 is set to a position facing the receiver 9 provided on one side of the housing 1.

The helical antenna 7 is arranged so that the axial direction of its spiral portion is parallel to the whip antenna 3.

In the above structure, the helical antenna 7 is disposed at a position facing the receiver 9 provided on one side of the casing 1 of the portable radio telephone 20, so that the portable radio telephone 20 is used. In this state, the helical antenna 7 built in the housing 1 of the portable radio telephone 20 is located at the position farthest from the human hand or the human head, whereby the helical antenna 7 that is the built-in antenna is It is possible to significantly reduce the deterioration of the antenna characteristics. And this becomes remarkable as the housing 1 is miniaturized.

Further, since the helical antenna 7 is connected to the substrate 2 via the helical rising portion 8, the antenna characteristics of the helical antenna 7 which is a built-in antenna in the free space can be improved.

Further, since the helical antenna 7 is simply connected to the substrate 2, the number of assembling steps is small and the cost can be reduced.

FIG. 3 is a perspective view showing a use state of the portable radio telephone 20 in which the antenna device shown in FIGS. 1 and 2 is arranged.

In the use state shown in FIG. 3, it can be seen that the helical antenna 7 built in the housing 1 of the portable radio telephone 20 is located at the farthest position from the human hand 6 and the human head 5. As a result, the deterioration of the antenna characteristics of the helical antenna 7 which is the built-in antenna can be significantly reduced.

The antenna device using the helical antenna 7 of the first embodiment is compared with the antenna device using the inverted F antenna 4 shown in FIG. 6, that is, the antenna characteristics during a call are compared. The antenna device of the first embodiment had a gain of about 2-3 dB higher.

Further, when the helical rising portion 8 is provided between the helical antenna 7 and the substrate 2, the gain is higher by about 1 to 2 dB on average as compared with the other case.

FIG. 4 is a schematic perspective view showing a second embodiment of the antenna device according to the present invention. In the antenna device of the second embodiment, the helical antenna 7 is arranged so that the axial direction of its spiral portion is perpendicular to the whip antenna 3 and perpendicular to the surface of the substrate 2. Other configurations are shown in FIG.
And is the same as that shown in FIG. In addition, in FIG. 4, the helical starting portion 8 shown in FIGS.
Although not formed, the helical rising portion 8 as shown in FIGS. 1 and 2 may be formed also in the configuration shown in FIG.

FIG. 5 is a schematic perspective view showing a third embodiment of the antenna device according to the present invention. In the antenna device of the third embodiment, the helical antenna 7 is arranged so that the axial direction of its spiral portion is perpendicular to the whip antenna 3 and parallel to the surface of the substrate 2.

Further, a cutout portion 2a is formed at a position where the helical antenna 7 is arranged on the substrate 2, and the helical antenna 7
Are arranged in the cutout 2a.

In the third embodiment shown in FIG. 5 as well, the helical rising portion 8 shown in FIGS. 1 and 2 is not formed, but in the configuration shown in FIG.
Also, the helical rising portion 8 as shown in FIG. 2 may be formed.

[0036]

As described above, according to the present invention, the wireless communication circuit board is built in, and the wireless communication circuit board is installed in the housing of the portable wireless telephone having the receiver on one side of the top and can be housed in the housing. In an antenna device having a whip antenna disposed in a housing and a built-in antenna housed in the housing, the built-in antenna is composed of a helical antenna, and the helical antenna is separated from the installation position of the whip antenna, and the housing Since it is arranged so as to face the receiver of the body, it is possible to remarkably reduce the deterioration of the antenna characteristics due to the human hand or the human head when the person holds the case to talk. Provide an antenna device that can obtain a good diversity effect even when the housing of a mobile phone is downsized, and has a simple structure and low cost There is an effect that it is Rukoto.

[Brief description of the drawings]

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

2 is a front view of the first embodiment shown in FIG. 1. FIG.

FIG. 3 is a perspective view showing a usage state of a mobile wireless telephone provided with the antenna device shown in FIGS. 1 and 2.

FIG. 4 is a schematic perspective view showing a second embodiment of the antenna device according to the present invention.

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

FIG. 6 is a perspective view of a conventional antenna device.

FIG. 7 is a perspective view showing a usage state of a conventional antenna device.

FIG. 8 is a configuration diagram of a conventional inverted F antenna.

[Explanation of symbols]

 1 Case 2 Substrate 3 Whip Antenna 5 Human Head 6 Hands 7 Helical Antenna 8 Helical Start-up Section 9 Receiver 20 Mobile Radio Phone

Claims (6)

[Claims] 1. A whip antenna, which is installed in a housing of a portable wireless telephone having a built-in wireless communication circuit board and a receiver on one side of its top, and is housed in the housing, and the housing. An antenna device comprising a built-in antenna housed in the body, wherein the built-in antenna is composed of a helical antenna, the helical antenna is separated from a position where the whip antenna is disposed, and faces the receiver of the housing. An antenna device, which is arranged at a position. 2. The antenna device according to claim 1, wherein the helical antenna has a rising portion, and is connected to the wireless communication circuit board via the rising portion. 3. The antenna device according to claim 1, wherein the helical antenna is arranged so that its axial direction is parallel to the whip antenna. 4. The antenna device according to claim 1, wherein the helical antenna is arranged such that its axial direction is perpendicular to the whip antenna and perpendicular to the surface of the wireless communication circuit board. . 5. The antenna device according to claim 1, wherein the helical antenna is arranged such that an axial direction thereof is perpendicular to the whip antenna and parallel to a surface of the wireless communication circuit board. . 6. The antenna device according to claim 5, wherein the wireless communication circuit board has a cutout portion, and the helical antenna is arranged in the cutout portion.