JPH04103006U - portable radio antenna - Google Patents

Abstract

(57) [Summary] [Purpose] To obtain an antenna for a portable radio device that is not cumbersome to handle and is suitable for a portable radio device. [Structure] A dielectric substrate 3 is provided on the outer surface of a ground electrode 5 that shields a high frequency circuit 1. A microstrip line 6 is provided on the other surface of the dielectric substrate 3, and a microstrip line 6 is provided facing the microstrip line 6 for waveguide. It has a structure in which an electrode 8 is provided, and a microstrip line 6 is used as a radiator.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is applicable to portable radio equipment such as transceivers, mobile phones, and cordless telephones. This relates to the structure of the installed antenna.

0002

[Conventional technology]

For example, as shown in Figure 3, a portable radio device has a housing that is large enough to be easily held with one hand. 11 is provided with a rod-shaped antenna 12 for transmitting and receiving. Also, on one side of the housing 11 A telephone receiver 13, a transmitter 14, and a numeric keypad 15 are provided.

0003 The length of the rod-shaped antenna 12 is approximately 1/4 of the wavelength of the high-frequency signal used for transmission and reception. Therefore, when the portable radio is not in use, it can be stored inside the housing 11, making it convenient to carry. It has become. The rod-shaped antenna 12 is a monopole antenna, and the housing 11 A device that operates as an antenna by pairing with a grounding plate (not shown) installed inside. It is.

0004

[Problem that the idea aims to solve]

By the way, since the rod-shaped antenna 12 protrudes from the housing 11, it may come in contact with the human body during use. It is easy to break when it hits surrounding equipment. Also, let's store the rod antenna 12 inside the housing 11. When you press the tip of the rod-shaped antenna 12 as a It was expensive.

[0005] Moreover, when the rod-shaped antenna 12 is housed in the housing 11, it functions as a monopole antenna. In some cases, even if there was an incoming signal when using a mobile phone, it could not be received. .

[0006] Furthermore, the size of the ground plate required for a monopole antenna is determined by the diameter or side. must be circular or square with the same wavelength as the high-frequency signal used for transmission and reception. is preferred. For example, for a high frequency signal of 1 GHz, a size of 30 cm is preferable. However, since there is a limit to the size of the housing 11 for portable radios, the ground plate must be of an ideal size. I had no choice but to make it smaller than it was. Therefore, the radiation efficiency was low.

[0007] Therefore, this idea solved the above problems and proposed an antenna suitable for portable radio equipment. This is what we provide.

[0008]

[Means to solve the problem]

The portable radio antenna based on this invention shields the high frequency circuit of the portable radio. a grounding electrode, a dielectric substrate with one side in contact with the outer surface of the grounding electrode, and a dielectric substrate. A microstrip line in contact with the other side of the line, and a line facing the microstrip line The microstrip line is equipped with waveguide electrodes spaced apart from each other, and the microstrip line is used as a radiator. It is used as

[0009]

[Effect]

The ground electrode serves both as a shield for the high frequency circuit and as a ground conductor for the microstrip line. Well, a microstrip line is used as an antenna radiator, and a waveguide electrode is used as an antenna radiator. Improve radiation efficiency. These components should not protrude outside the portable radio casing. There is no.

0010

【Example】

FIG. 1 is a sectional view of essential parts of a portable radio device showing a first embodiment of this invention. Based on this, the antenna for the portable radio device according to this invention will be explained below.

[0011] In Figure 1, numeral 11 is the casing of the portable radio, which is made of synthetic resin, for example. Ru. A printed circuit board 2 on which a high frequency circuit 1 is arranged is housed in the casing 11. On one side of the printed circuit board 2, there is a box-shaped shield that also serves as a dielectric board 3. It is covered with cover 4.

0012 A ground electrode 5 is provided over almost the entire inner surface of the shield cover 4. The ground electrode 5 is electrically connected to a ground circuit (not shown) arranged on the printed circuit board 2. It is connected to electrically shield the area around the high frequency circuit 1. shield cover 4 is further provided with a microstrip line 6 on the outer surface of the left side. The cross-strip line 6 is formed by a conductor 7 passing through the dielectric substrate 3 and the ground electrode 5. is connected to the antenna connection end on the printed circuit board 2 side. This structure The dielectric substrate 3, ground electrode 5, and microstrip line 6 are connected to a microstrip aperture. constitutes the antenna. In other words, this microstrip antenna has a shield cover. There are 4 bars available. In addition, the ground electrode 5 and the microstrip The line 6 is tightly attached to the surface of the shield cover 4 by metal vapor deposition or electroless plating. It is covered in a worn condition.

[0013] 8 is a waveguide electrode provided on the inner surface of the housing 11 facing the microstrip line 6 It is applied to the housing 11 by metal vapor deposition or electroless plating, but there are certain Alternatively, it is made by pasting metal foil with adhesive. This waveguide electrode 8 is used as a radiator. It functions as a wave director for the microstrip line6, which functions as a microstrip line. Improve the radiation efficiency of trip antenna.

[0014] FIG. 2 is a sectional view of essential parts of a portable radio device showing a second embodiment of this invention. Figure 2 The difference between the band radio and the one shown in Figure 1 is that the waveguide electrode 9 functions as a waveguide. However, the nameplate fixed to the outer surface of the casing 11 also serves as a nameplate. This nameplate is For example, it is an aluminum plate or an aluminum plate, and is attached to the housing 11 with adhesive.

[0015] Next, the sizes of the microstrip line 6 and waveguide electrodes 8 and 9 will be explained. . The preferred length l of the microstrip line 6 is determined by the dielectric constant ε of the dielectric substrate 3, Determined by the wavelength λ of the high frequency signal used for transmission and reception, the microstrip line If line 6 is composed of a microstrip line with one end grounded, the length l is expressed as equation 1. For example, assuming that ε=5 and the frequency of the high-frequency signal is 1GHz, λ=30. By substituting cm, we get Equation 2. Also, the width of the microstrip line6 should be reduced as much as possible. By increasing the size, the radiation efficiency of the microstrip antenna can be improved.

[0016]

[Math 1]

[0017]

[Math 2]

[0018] The waveguide electrodes 8 and 9 are approximately the same size as the microstrip line 6. , microstrip line 6 separated by 0.05λ to 0.15λ It is located so that it overlaps with track 6. According to experiments, considering the distance between the two The directivity and frequency characteristics of the microstrip antenna change due to The distance between the two is selected within the above range depending on the performance.

[0019] These waveguide electrodes 8,9 are used to improve the radiation efficiency of the microstrip antenna. Not only that, but it also has the effect of expanding the frequency band. For example, waveguide electrodes8,9 By changing the size of the waveguide electrode and the size of the microstrip line6, 8,9 and the microstrip line 6 by slightly changing the resonant wavelength of the microstrip line 6. The waveguide line 6 is made to resonate in the short wavelength region of the frequency band used, and the waveguide electrodes 8 and 9 By resonating in the long wavelength region of the band, relatively uniform radiation can be achieved over the entire frequency band used. The radiation efficiency can be obtained. In other words, compared to the case without waveguide electrodes 8, 9, the operating frequency is The range can be expanded.

[0020]

[Effect of the idea]

The antenna of the portable radio device based on this invention can be inserted and removed from the case of the portable radio device. Since there is no need to do this, there is no need to worry about handling it, and you can receive incoming signals even when you are carrying it. can. Furthermore, since it does not protrude outside the housing, it will not be damaged during handling. difference Furthermore, the radiation efficiency is high, and uniform radiation efficiency can be obtained over the entire frequency band used. In addition, the antenna of this portable radio device has its components protected from the casing or shield inside the casing. Since it can be provided using a cover, it can be manufactured at a very low cost.

[Brief explanation of drawings]

FIG. 1 is a sectional view of essential parts of a portable radio device according to a first embodiment of the invention.

FIG. 2 is a sectional view of essential parts of a portable wireless device according to a second embodiment of the invention.

FIG. 3 is an external view of a conventional portable radio device.

[Explanation of symbols]

1 High frequency circuit 2 Printed circuit board 3 Dielectric substrate 4 Shield cover 5 Ground electrode 6 Microstrip line 7 Conductive member 8,9 Waveguide electrode 11 Housing

Claims (2)

[Scope of utility model registration request] 1. A ground electrode that shields a high frequency circuit of a portable radio, a dielectric substrate with one surface in contact with the outer surface of the ground electrode, a microslip line in contact with the other surface of the dielectric substrate, What is claimed is: 1. An antenna for a portable wireless device, comprising: a waveguide electrode disposed facing and separated from a microstrip line; and using the microstrip line as a radiator. 2. Claim 1, wherein the waveguide electrode is a nameplate fixedly held on the outer surface of the casing of the portable radio device.
Antenna of radio equipment published in.