JP2004011237A - Radio absorbing panel for set in outdoor building - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio absorbing panel for set in an outdoor building conformable to radio absorption of a wide band and forming a lightweight structure. <P>SOLUTION: The radio absorbing panel 1 for set in the outdoor building comprises a metallic radio reflector 3, bar-type ferrite magnetic bodies 1 arranged on the radio reflector at prescribed intervals to absorb radio waves, and an outer surface protective member for the ferrite magnetic bodies. The outer surface protective member is formed of a surface protective plate 4 for covering the front surface of the ferrite magnetic body group and a waterproof member 5 for sealing the end surface of the ferrite magnetic bodies arranged at end parts. The outer surface protective member may be formed of a fiber-reinforced plastic for covering the exposed surface of each ferrite magnetic body. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a radio wave absorbing panel installed on an outdoor building, and more particularly, to a light absorbing panel installed on a lightweight outdoor building capable of coping with broadband radio wave absorption.
[0002]
[Prior art]
In high-rise buildings, various facilities are installed on the roof, and related rooftop beam sections, equipment racks, blindfolded wall building members, and outdoor structures such as steel towers as necessary are provided. . For this reason, when a situation where electromagnetic waves flying around in the surroundings are blocked by the outdoor building is formed, the electromagnetic waves are reflected on the outdoor building and generate secondary noise in the surroundings, causing new electromagnetic interference. However, at present, electromagnetic waves constantly flying around the outdoor building form a wide frequency band of 90 to 770 MHz by both VHF and UHF television radio waves.
[0003]
Therefore, when a high-rise building is constructed, a television reflected on the structure causes radio interference such as a ghost in a wide area, and thus a measure for preventing a radio wave interference in a high-rise building has been studied.
[0004]
Various measures have been taken to prevent the reflection of TV radio waves from affecting a far and wide area, but radio wave absorption panels have been adopted as measures to absorb radio waves without reflecting them. The conventional radio wave absorbing panel 20 has a ferrite tile 21 spread over a reflective metal plate 22 as illustrated in FIG. 4 and has an electromagnetic wave absorbing performance by being arranged in an outdoor building by a support member 23. .
[0005]
However, since the ferrite tile 21 of the radio wave absorbing panel 20 has a narrow frequency band of electromagnetic waves to be absorbed, a single ferrite tile cannot cope with a wide frequency band. Was supported.
[0006]
For this reason, radio wave absorbing panels with ferrite tiles are difficult to cope with wide band frequencies, and the installation is to apply an eccentric load to the tower structure etc. in order to install only in the direction of radio wave arrival. It became a major instability factor for the tower structure.
[0007]
For this reason, it is necessary to structurally reinforce an outdoor building such as a steel tower structure, which leads to an increase in the amount of steel frames and the like, which causes a cost increase. The radio wave absorption panel has been a problem that needs to be improved more than measures for high-rise buildings.
[0008]
[Problems to be solved by the invention]
The present invention has been made in view of the above problems, and has been proposed to solve the problem, and provides a radio wave absorption panel that can be installed in an outdoor building that can cope with broadband radio wave absorption and that forms a lightweight structure. ing.
[0009]
[Means for Solving the Problems]
The radio wave absorption panel installed on the outdoor building according to the present invention is basically a metal-made radio wave reflection plate and a bar-shaped ferrite magnetic material arranged at a predetermined interval so as to absorb radio waves on the radio wave reflection plate, and It is composed of an outer surface protection member of a bar-shaped ferrite magnetic body. Specifically, the outer surface protection member is a surface protection plate that covers the front surface of the bar-shaped ferrite magnetic body group and a bar-shaped ferrite magnetic material disposed at an end. It is characterized in that it is made of a waterproof material that closes off the small face of the body and reinforces the outer surface with waterproof ribs, or is made of fiber-reinforced plastic that covers the exposed surface of each ferrite magnetic body.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
The radio wave absorption panel installed on the outdoor building according to the present invention is basically a metal-made radio wave reflection plate and a bar-shaped ferrite magnetic material arranged at a predetermined interval so as to absorb radio waves on the radio wave reflection plate, and It is composed of a bar-shaped ferrite magnetic material outer surface protection member.
[0011]
Hereinafter, an embodiment of a radio wave absorption panel installed in an outdoor building according to the present invention will be described in detail with reference to the drawings.
[0012]
FIG. 1 shows an embodiment of a radio wave absorbing panel according to the present invention, which is shown in a vertical sectional perspective view (a) and a partially cutaway plan view (b).
In the embodiment of the radio wave absorption panel according to the present invention, the radio wave absorption panel 1 is configured by arranging a rectangular parallelepiped ferrite magnetic body 2 on a radio wave reflection plate 3 as shown in the figure.
[0014]
The bar-shaped ferrite magnetic bodies 2 are rectangular parallelepiped ferrite magnetic bodies having a predetermined thickness, height, and length, and are arranged in parallel at intervals such that their longitudinal directions are the same. The direction of the magnetic field of the radio wave coincides with the longitudinal direction of the bar-shaped ferrite magnetic body 2, and the direction of the electric field of the radio wave is orthogonal to the longitudinal direction of the bar-shaped ferrite magnetic body 2.
[0015]
The above-described configuration of the radio wave absorption panel 1 is similar to a broadband ferrite magnetic wave radio wave absorption device (see Japanese Patent Application Laid-Open No. 4-42999), and converts a radio wave into a TM wave without absorbing it as a TEM wave and absorbs it. When the input impedance and the characteristic impedance of the transmission line are represented as an equivalent circuit using the above configuration as a transmission line model, a desired relationship is established between the input impedance of the ferrite magnetic material, the wavelength of the operating frequency of the operating radio wave, and the characteristic impedance. To form a zero reflection state.
[0016]
The arrayed bar-shaped ferrite magnetic bodies 2 are coated on the front surface thereof with a surface protection plate 4 made of fiber-reinforced plastic to prevent intrusion of moisture, and are also provided at the end portions of the bar-shaped ferrite magnetic bodies 2 ′. The small ferrule magnetic body 2 is formed in a waterproof state by closing the small face 2 ′ with the waterproof material 5.
[0017]
As described above, the radio wave absorbing panel 1 according to the present invention achieves a wide absorption frequency band and a weight reduction of about 40 to 60% by arranging the ferrite magnetic material of the radio wave absorber in a cross shape. I am planning.
[0018]
That is, although the shape and arrangement of the cross-shaped ferrite magnetic material change depending on the incident angle of the radio wave, assuming that the weight of the conventional radio wave absorbing panel is 50 kg, in the present embodiment showing the same performance, The incident angle can be reduced to 20 kg or less at an incident angle of 60 degrees, and can be reduced to about 30 kg even in the case of front incidence, which is the worst incident angle.
[0019]
Also, the absorption frequency formed by the bar-shaped arrangement can be broadened to 1000 MHz or more, while the absorption band width of the conventional radio wave absorption panel is 14 dB or more and 150 MHz or less.
[0020]
Next, another embodiment of the radio wave absorption panel installed in the outdoor building according to the present invention will be described.
[0021]
The embodiment of FIG. 2 which is shown in a vertical sectional perspective is an example in which the strength of the radio wave absorbing panel is improved.
[0022]
The radio wave absorbing panel 6 according to the present embodiment is such that the outer surface of the radio wave absorbing panel 1 described in the above embodiment is reinforced by a U-shaped waterproof rib 7 arranged at the fore-edge portion. By pressing the surface protection plate 4 covering the front surface of the base 2 and the waterproof material 5 sealing the small side surfaces of the bar-shaped ferrite magnetic bodies 2 ′ and 2 ′ arranged at the ends on the radio wave reflection plate 3, the radio wave is generated. The whole of the absorption panel 6 is formed as a strong integrated unit.
[0023]
The embodiment shown in a perspective perspective view in FIG. 3 is an example in which the radio wave absorption panel is further improved in terms of function and weight.
[0024]
The radio wave absorption panel 10 in the present embodiment employs a fiber reinforced plastic 11 as an outer surface protection member, and covers the exposed surface of each bar-shaped ferrite magnetic body 2 and simultaneously disposes the array of each bar-shaped ferrite magnetic body 2. Is configured to be printed on the surface 12 of the radio wave reflecting plate 3 which is exposed to light.
[0025]
Therefore, since the radio wave absorbing panel 10 in the present embodiment does not have another dielectric or the like interposed between the cross-shaped ferrite magnetic bodies 2, it is necessary to maximize the radio wave absorbing function in a normal state. Since the surface protection plate 4 and the waterproof material 5 arranged in each of the above embodiments are omitted, the weight is greatly reduced.
[0026]
As described above, the radio wave absorption panel installed on the outdoor building according to the present invention is configured as described in detail in each embodiment, and thus solves the problems of the conventional radio wave absorption panel. In addition to making the frequency of the absorbed radio waves compatible with a wide band, the eccentric load of the steel tower structure installed by reducing the weight is eliminated, eliminating the need to structurally reinforce the outdoor building Cost reduction has been achieved.
[0027]
As described above, the radio wave absorbing panel to be installed in the outdoor building according to the present invention has been described in detail based on the above embodiments. However, the present invention is not limited to these embodiments, and It goes without saying that various changes can be made to specific structures and materials such as a magnetic material, a waterproof material, a waterproof rib, and a fiber-reinforced plastic without departing from the gist of the invention.
[0028]
【The invention's effect】
The radio wave absorption panel installed on the outdoor building according to the present invention is basically a metal radio wave reflection plate and a bar-shaped ferrite magnetic material arranged at a predetermined interval so as to absorb radio waves on the radio wave reflection plate. And a bar-shaped ferrite magnetic body comprising an outer surface protection member of a bar-shaped ferrite magnetic body, and more specifically, a surface protection plate covering the front surface of the bar-shaped ferrite magnetic body group and a bar-shaped ferrite magnetic body disposed at an end portion. It is made of a waterproof material that closes off the small surface and reinforced the outer surface with waterproof ribs, or is made of fiber-reinforced plastic that covers the exposed surface of each ferrite magnetic body, so that the frequency of the absorbed radio wave can be broadened. In addition, the effect of reducing the installation cost by reducing the weight is achieved.
[Brief description of the drawings]
FIG. 1 is a diagram of an embodiment of a radio wave absorbing panel installed on an outdoor building according to the present invention. FIG. 2 is a diagram of another embodiment of a radio wave absorbing panel according to the present invention. FIG. Embodiment diagram [Fig. 4] Conventional radio wave absorption panel diagram [Description of reference numerals]
1, 6, 10 radio wave absorption panel, 2, 2 'cross-shaped ferrite magnetic material,
3, 22 radio wave reflection plate, 4 surface protection plate, 5 waterproof material, 7 waterproof rib,
11 fiber reinforced plastic, 12 surface, 20 radio wave absorption panel,
21 ferrite tiles, 23 support members,

Claims (4)

An outdoor structure comprising a metal radio wave reflecting plate, a bar-shaped ferrite magnetic body arranged at predetermined intervals on the radio wave reflecting plate to absorb radio waves, and an outer surface protection member of the bar-shaped ferrite magnetic body Radio wave absorption panel to be installed in The outer surface protection member is composed of a surface protection plate for covering the front surface of the crosspiece ferrite magnetic body group and a waterproof material for closing a small face of the crosspiece ferrite magnetic body disposed at an end. A radio wave absorbing panel installed on the outdoor building according to 1. The radio wave absorbing panel installed in an outdoor building according to claim 2, wherein the waterproof material has an outer surface reinforced with a waterproof rib. The radio wave absorption panel installed in an outdoor building according to claim 1, wherein the outer surface protection member is made of a fiber reinforced plastic covering an exposed surface of each of the crosspiece ferrite magnetic bodies.

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