JPH1141018A - Antenna for portable radio - Google Patents

Abstract

(57) [Problem] To provide an antenna for a portable wireless device in which electrical characteristics do not change when the antenna is extended and stored. SOLUTION: A coil-shaped element (3) protruding outside a housing of a wireless device and formed of a spiral conductor, and passes through the inside of the coil-shaped element (3) in the axial direction, and is put into and out of the housing. A possible non-conductor dummy antenna (1) is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an extendable and retractable antenna used for a portable radio, and more particularly to an antenna for a portable radio in which the characteristics of the antenna do not change during extension and storage.

[0002]

2. Description of the Related Art In an antenna for a portable radio, a whip antenna having an electrical length of about a half wavelength of a resonance frequency with little gain deterioration due to a human body is often used in order to secure communication quality during a call. . However, a portable wireless device that requires mobility has a problem that if the whip antenna is left exposed, the antenna becomes a hindrance when being carried.

Therefore, generally, the portability is improved by allowing the whip antenna 7 to be accommodated in a housing 8 as shown in FIG. In this case, the problem is to secure the gain of the antenna when the antenna is extended and when it is stored.
Japanese Unexamined Patent Publication No. 57608, Japanese Unexamined Patent Publication No. Hei. 232614, Japanese Unexamined Patent Publication No. Hei 6-252620, etc. disclose techniques.
Specifically, Japanese Utility Model Laid-Open Publication No. 6-57608,
Japanese Patent No. 2620 discloses a rod antenna in which a coil-shaped portion is formed at the tip of the antenna and the coil-shaped portion is covered with a synthetic resin. In the antenna for a portable wireless device disclosed in JP-A-6-232614, FIG. a) As shown in FIG.
A first conductor 12 covered with an insulator, and a pipe-shaped second conductor accommodating the conductor 12.
A conductor 9 and a covering member 10 for covering the tip of the first conductor 12
There is an antenna for a portable wireless device that is provided with a ground 14 that contacts the lower portion of the second conductor 9 when the antenna is housed. When the antenna is housed, only the covering member 10 protrudes from the housing 8 as shown in FIG.

However, in the above-described antenna, since the antenna element that expands and contracts is used as a conductor, there is a problem that the electrical length of the antenna differs between when it is extended and when it is stored, and there is a difference in gain and directivity pattern. Furthermore, in the prior art, since the rod-shaped portion of the antenna has electrical characteristics, it is not suitable for miniaturization. For example, there is a method of reducing the storage space by using a rod shape, but it is mechanically complicated and has problems in terms of cost and durability.

[0005] In a portable radio antenna,
Normally, when the electrical length is long, the extension is more efficient, but the actual use status of the portable radio is in a standby state for 90% or more of the time, and in the portable radio mainly used for carrying, The antenna is mostly stowed. Therefore, there is a problem that it is not desirable that the characteristics change when the antenna is expanded and contracted.

[0006] On the other hand, a portable wireless device in which the expansion and contraction of the antenna is eliminated can solve the above problem, but does not allow the user to extend and contract the antenna. The act of expanding and contracting the antenna is a status act of one user who shows differentiation and a sense of quality from a PHS or the like and a radio device, and is an element that cannot be excluded from the development concept. Furthermore, in recent years, there has been a concern that the electromagnetic waves may affect the human body, and each manufacturer voluntarily separates the human body from the antenna by a predetermined distance t as shown in FIG. It is designed to be. However, as described above, in the related art, the rod-like portion of the elongated antenna is a whip antenna made of a conductor, and a material that moves flexibly is selected in consideration of breakage and the like.
It is natural that the portable wireless device communicates while moving, and it is easy to imagine that the flexible and conductive rod-shaped antenna portion swings. That is, as shown in FIG. 6A, at the time of rest, the human body and the antenna 11 are separated by a predetermined distance t.
Even if the user is far away, there is a case where there is no distance between the human body and the antenna during the movement as shown in FIG. 6B, and the effect of the electromagnetic waves on the human body is a problem.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned conventional problems. An object of the present invention is to provide an antenna for a portable radio which does not change its electrical characteristics when the antenna is extended and retracted. The purpose is to provide. Another object of the present invention is to provide an antenna for a portable wireless device that allows the user to expand and contract the antenna by himself.

It is still another object of the present invention to provide an antenna for a portable wireless device capable of holding a source of an electromagnetic wave and a human body at a predetermined distance even when moving during a call.

[0009]

In order to solve the above-mentioned problems, an antenna for a portable wireless device according to the present invention includes a coil-shaped element (3) formed of a spiral conductor and protruding outside a housing of the wireless device. And a dummy antenna (1) made of a non-conductor, which can be inserted into and removed from the housing, on the same axis as the coil-shaped element (3). With this configuration, since the dummy antenna (1) is made of a non-conductor, when the dummy antenna (1) is extended and stored,
The electrical characteristics of the coil element (3) functioning as an antenna do not change.

Further, in the antenna for a portable wireless device according to the present invention, the coil-shaped element (3) has an electrical length of approximately 又 は or の of the resonance frequency, and is capable of transmitting and receiving. Is optional. The antenna for a portable wireless device according to claim 1, wherein the coil-shaped element is made of a non-conductor.
Cover (4) is provided to protect the cover. When the coil-shaped element (3) is exposed, there is a problem in appearance and strength, and the frequency of the antenna is prevented from shifting.

An antenna for a portable wireless device according to any one of claims 1 to 3, wherein said dummy antenna (4).
Is made of a material having no electrical connection, such as ABS, urethane, and nylon. In the portable wireless device antenna according to any one of claims 1 to 4, the dummy antenna (1) may have a shape of a multi-stage rod antenna.

The coil element (3) is made of a coil conductor having a predetermined number of turns and wound without a gap. Further, the coil-shaped element (3) may have a predetermined number of turns, and may be formed of a coil-shaped conductor formed with a gap provided in a part thereof.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. Here, FIG. 1 is a schematic diagram showing the shape of an antenna for a portable wireless device according to an embodiment of the present invention.
FIG. 3 is a front view showing a state when the portable radio antenna according to the embodiment of the present invention is designed using an actual portable radio.

As shown in FIG. 1, an antenna for a portable radio includes a dummy antenna 1 having a knob 2 at a tip on a housing 5 and a coil-shaped element 3 housed in a cover 4.
Are provided. The dummy antenna 1 is made of a material such as synthetic resin having no electrical connection such as ABS, urethane, and nylon, and is attached to the housing 5 so as to be able to be taken in and out. Similarly, the knob 2 at the tip is made of a material having no electrical connection, and has a semi-spherical shape that can be easily gripped during expansion and contraction. The knob 2 is designed to have a larger diameter than the dummy antenna 1 in order to prevent the dummy antenna 1 from immersing in the housing 5. Although not shown, a stopper for preventing the dummy antenna 1 from dropping out of the housing 5 when the dummy antenna 1 is extended is provided at the rear end. . Since the dummy antenna 1 has no electrical coupling, the design of the dummy antenna 1 can be designed with emphasis on design and space, and it is easy to realize an antenna for a portable wireless device that emphasizes miniaturization. In the present embodiment, the dummy antenna 1
Has a linear antenna shape, but is not limited to this, and may have a shape like a small, small-diameter multistage telescopic rod antenna.

The coil-shaped element 3 has a structure in which the coil-shaped element 3 is directly attached to the housing 5 or the substrate by screwing or the like. The coil-shaped element 3 has a predetermined number of turns and has an electrical length of approximately 又 は or の of the resonance frequency.
It itself functions as an antenna. In addition,
The electrical length of the coil-shaped element 3 is not limited to the above-described electrical length as long as transmission and reception can be performed, and is arbitrary.

For example, the coil-shaped element 3 is 0.8 m
m, the number of coil turns is about 7, and about 40 in the axial direction.
Some are designed with a length of mm. In the present embodiment, the coil-shaped element 3 is configured by winding a spiral conductor so as to have no gap. However, the present invention is not limited to this. Of course, a configuration is also possible. This is because, assuming that the operating frequency is generally the same, the smaller the gap is, the smaller the antenna is (the smaller the winding diameter of the same coil is, the smaller the number of turns is). The number of turns of the coil increases, and the shape (length of the coil) increases. However, in general, the smaller the antenna, the smaller the efficiency and the bandwidth used. It is effective to determine the number of turns and the size of the gap in consideration of the electrical performance.

Although the dummy antenna 1 slides coaxially within the coil-shaped element 3, the electrical characteristics of the coil-shaped element 3 change because the dummy antenna 1 has no electrical coupling. Absent. For this reason, an antenna whose electrical characteristics do not change even when the antenna (dummy antenna 1) is expanded and contracted can be realized. That is, the same gain can be obtained both when the dummy antenna 1 is extended and when it is stored. In addition, the coil-shaped element 3 can have an electrical length longer than its actual height by helically winding the conductor, so that sufficient electrical characteristics can be ensured.

The cover 4 covers and protects the coil-shaped element 3. If the coil-shaped element 3 is exposed, there is a problem in appearance and strength, and it is prevented that the frequency of the antenna is shifted. It is for.
The cover 4 is made of a material having no electrical connection, such as ABS, urethane, or nylon, like the dummy antenna 1. A screw portion 6 is attached to a lower end of the cover 4 and is attached to the housing 5 by screws. The screw portion 6 functions as a power supply portion.

FIGS. 2 and 3 show a state where the antenna is actually attached to the portable wireless device. FIG. 2 shows a state where the dummy antenna 1 is extended, and FIGS. 3 (a) and 3 (b) ,
This is when the dummy antenna 1 is stored. In particular, since the only part that swings due to movement during a call is the dummy antenna 1, the coil-shaped element 3, which is a source of electromagnetic waves, is attached to the housing 5, so as shown in FIG. In addition, the distance from the human body can always be kept constant.

It should be noted that the present invention is not limited to the present embodiment, and various modifications can be provided without departing from the spirit of the present invention. Range.

[0021]

According to the present invention, the wireless device protrudes outside the housing,
A coil-shaped element (3) formed of a helical conductor and coaxially with the coil-shaped element (3),
By providing a dummy antenna (1) made of a non-conductor that can be taken in and out of the housing, an antenna for a portable wireless device whose electrical characteristics do not change when the antenna is extended and stored is provided. Becomes possible.

Further, since the dummy antenna (1) is provided, the antenna itself can be expanded and contracted. Furthermore, since the dummy antenna (1) is made of a non-conductor, it can be maintained at a predetermined distance from the source of the electromagnetic wave and the human body even when moving during a call, and there is an effect that the electromagnetic wave does not affect the human body.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a shape of an antenna for a portable wireless device according to an embodiment of the present invention.

FIG. 2 is a front view showing a use state when the portable wireless device antenna according to the embodiment of the present invention is designed using an actual portable wireless device.

3A and 3B are diagrams showing a state where an antenna is actually attached to the portable wireless device, wherein FIG. 3A is a top view when the dummy antenna 1 is stored, and FIG. 3B is a front view.

FIG. 4 is a perspective view showing an example of a conventional portable radio antenna.

5A and 5B are perspective views showing another example of a conventional antenna for a portable wireless device, in which FIG. 5A shows a state of extension and FIG. 5B shows a state of storage.

6A and 6B are diagrams illustrating a usage state of a conventional antenna for a portable wireless device, in which FIG. 6A illustrates a usage state of the antenna for a portable wireless device in a stationary state, and FIG. It is a figure showing the state where it is in contact with the human body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Dummy antenna 2 Knob 3 Coiled element 4 Cover 5 Housing 6 Screw part

Claims (7)

[Claims] A coil-shaped element protruding outside the housing of the wireless device and formed of a spiral-shaped conductor; and a dummy antenna formed of a non-conductor coaxially with the coil-shaped element and capable of being inserted into and removed from the housing. And an antenna for a portable wireless device. 2. The antenna according to claim 1, wherein said coil-shaped element has an electrical length of approximately 電 気 or ほ ぼ of a resonance frequency. 3. The antenna for a portable wireless device according to claim 1, wherein a cover made of a non-conductor and protecting the coil-shaped element is provided. 4. The portable wireless device antenna according to claim 1, wherein the dummy antenna is made of a material having no electrical connection, such as ABS, urethane, and nylon. For portable radios. 5. The antenna for a portable wireless device according to claim 1, wherein the dummy antenna has a multi-stage rod antenna shape. 6. The antenna for a portable wireless device according to claim 1, wherein the coil-shaped element is formed of a coil-shaped conductor having a predetermined number of turns and wound without a gap. For portable radios. 7. The antenna for a portable wireless device according to claim 1, wherein the coil-shaped element has a predetermined number of turns, and is formed of a coil-shaped conductor formed with a gap provided in a part thereof. An antenna for a portable wireless device.