JPH0774496A - Radio-wave absorbing panel - Google Patents

Abstract

PURPOSE:To provide a light radio-wave absorbing panel in structure suitable even for a complex surface configuration, by inserting tube-shaped ferrite bodies between reinforcing bars at least partly. CONSTITUTION:A radio-wave absorbing panel has a plane part with a length (f) of 800mm and a circumference part with a length (e) of 1600mm, and a length (g) is 150mm and a height (h) is 200mm. At a plane part, plane ferrite plates 1 are arranged continuously in a magnetic field direction, while the ferrite plates 1 are arranged intermittently with a gap ratio of 70% in an electric field direction. At a circumference part has tube-shaped ferrite bodies 3 each with an outer diameter of 25mm, inner diameter of 6.1mm, and length of 40mm are inserted between reinforcing bars 2 in the electric field direction. Consequently, a lightweight radio-wave absorbing panel suitable even for a complex surface structure can be formed, and stable radio-wave absorbing characteristics are ensured irrespective of changes in angles of incidence of the radio wave.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio wave absorption panel which is attached to the outer wall of a high-rise building and prevents unnecessary reflected waves of television radio waves.

[0002]

2. Description of the Related Art Recently, unnecessary reflected radio waves from high-rise buildings have become an obstacle to television broadcasting, and radio wave pollution such as ghosts on television screens has become a problem. As a countermeasure for this, there is a method of embedding a radio wave absorber in the outer wall of a high-rise building, and various radio wave absorption panels in which these ferrite plates are embedded have been proposed. FIG. 3 shows a sectional view of an example of a conventional radio wave absorption PC panel, and FIG. 4 shows a structural view thereof. In this conventional example, the reinforcing bar 21 serving as a radio wave reflection plate is made of concrete 2
A ferrite plate 23 is embedded in the inside of the No. 2 and is continuously attached to the surface in the vertical direction with a gap in the horizontal direction. Further, an exterior material 24 such as granite is provided on the front surface.

[0003]

The outer surface of a high-rise building sometimes has a complicated structure such as a concave shape, a convex shape, or an arc shape in terms of structure and design. In such a case, it has been extremely difficult to form a radio wave absorption panel by arranging ferrite plates in a complicated structure such as a concave shape, a convex shape, or an arc shape by the conventional structure. Further, the radio wave absorption panel having the conventional structure has a problem that the weight is heavy. In view of the above problems, the present invention provides a structure of a radio wave absorption panel that can cope with even a complicated surface structure and can reduce the weight.

[0004]

According to the present invention, there is provided a radio wave absorption panel in which a ferrite plate is arranged on one surface of a concrete panel in which structural strength bars are embedded, and an exterior material is further applied, and at least one of the structural strength bars is provided. The tubular ferrite is inserted in the part.

[0005]

The present invention is effective in a panel having a complicated surface structure and in which ferrite plates cannot be arranged as in the conventional structure. By inserting a tubular ferrite into the structural strength line, the complicated surface structure as described above is obtained. Even in this case, a panel structure having a radio wave absorption characteristic can be configured. Moreover, a simple structure in which a cylindrical ferrite is inserted into the structural strength line is possible, and by bending the structural strength line, a complicated surface structure can be easily dealt with.

[0006]

FIG. 1 is a sectional view of an embodiment according to the present invention taken along the horizontal direction. This embodiment is a radio wave absorption panel having both a flat surface and a circumferential surface, the flat surface having a dimension f of 800 mm and the circumferential surface having a width dimension e of 1600 mm. The dimension g is 150 mm and the dimension h is 200 mm.
Is. In this flat portion, the flat ferrite plates 1 are arranged continuously in the magnetic field direction (vertical direction in the drawing) with a gap provided in the electric field direction (horizontal direction in the drawing).
The size of one of the ferrite plates 1 is 100 mm × 10
0 mm x 8 mm, the gap ratio in the direction of the electric field is about 70
%. Next, in the circumferential surface portion, a cylindrical ferrite 3 having an outer diameter of 25 mm, an inner diameter of 6.1 mm and a length of 40 mm was inserted into the structural strength line 2 (reinforcing bar having a diameter of 6 mm) in the electric field direction. According to this embodiment, the return loss at 100 MHz is 15.5 dB and the return loss at 200 MHz is 13 dB.
It was dB, and the return loss hardly changed even when the incident angle of the radio wave changed from vertical to 20 ° or 40 °. Further, according to the structure of the present embodiment, it is 25% as compared with the conventional structure.
It was possible to reduce the weight. Further, FIG. 2 shows a cross-sectional view of another embodiment according to the present invention taken along the horizontal direction. This embodiment is a radio wave absorption panel having a concave outer surface, and in a part thereof, the ferrite plates 4 are arranged continuously in the magnetic field direction with a gap provided in the electric field direction similarly to the conventional structure, and in the concave portion, A cylindrical ferrite 6 is inserted in the structural strength line 5. According to the present embodiment, it is possible to construct a radio wave absorbing panel having an outer surface having a concave shape, a convex shape, or an arc shape, and moreover, sufficient electric wave absorbing characteristics can be obtained. Further, the size of the tubular ferrite inserted into the structural strength line is appropriately determined according to the desired electromagnetic wave absorption characteristics. Further, the size of the mesh of the structural strength muscle into which the tubular ferrite is inserted is preferably 200 mm or less, and further, the mesh interval in the electric field direction is 100 to 200 mm, and the mesh interval in the magnetic field direction is 5.
It is preferably 0 to 100 mm. The tubular ferrite is inserted in the electric field direction.

[0007]

According to the present invention, it is possible to obtain a radio wave absorption panel which can be constructed even with a complicated surface structure and which can be made light in weight. It is possible to obtain a radio wave absorption panel whose characteristics do not change.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment according to the present invention.

FIG. 2 is a sectional view of another embodiment according to the present invention.

FIG. 3 is a sectional view of a conventional example.

FIG. 4 is a structural diagram of a conventional example.

[Explanation of symbols]

 1, 4 Ferrite plate 2, 5 Structural strength muscle 3, 6 Cylindrical ferrite

Claims (1)

[Claims] 1. A radio wave absorption panel in which a ferrite plate is arranged on one surface of a concrete panel in which structural strength reinforcements are embedded, and an exterior material is further applied, and tubular ferrite is inserted into at least a part of the structural strength reinforcements. The electric wave absorption panel characterized by having.