JPH11163580A - Nonreflective electromagnetic wave shield structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid electromagnetic pollution of sec. noises due to r-f reflection, by placing electromagnetic absorbers round a structure, except for a part directed to an incoming target electromagnetic wave. SOLUTION: A parabolic antenna 3 for receiving electromagnetic waves at 20-30 GHz from a communication satellite is installed on the top of a building 1. Other electromagnetic waves off from the antenna 3 irregularly reflect at a mounted iron tower 4 and electromagnetic waves 5 used for communication apparatus radiate in space to cause radio interference. To avoid this, a wall 6 having an electromagnetic shield and an absorber is installed around the tower 4 to approximately cover the top of the antenna 3 and tower 4, thereby shielding the electromagnetic waves radiated from itself owing to the shielding function of the wall 6 to avoid electromagnetic interference with the surrounding and suppress incoming electromagnetic waves from reflecting owing to the absorption function of the wall 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-reflection type electromagnetic wave shielding structure, and more particularly, to a non-reflection type electromagnetic wave shielding structure which absorbs an electromagnetic wave which is flying and does not reflect the electromagnetic wave to the surroundings.

[0002]

2. Description of the Related Art Recent buildings are required to sufficiently respond to the introduction of advanced information equipment such as OA equipment and personal computers and information systems using the same in response to the information age. For reasons they tend to shield the buildings themselves. In other words, the required performance required of a building in the information age is first, "prevention of malfunction of information equipment" that protects the equipment inside the building from unnecessary radiated radio waves from outside, and second, the performance inside the building. Computer systems and wireless LA
The third is the "secure of information security" for blocking the information leaked from the N to the outside as a low-level radio wave. Third, a channel caused by mutual interference of communication carriers when a wireless LAN or the like is used between adjacent buildings. It was the achievement of "advanced use of radio frequency" to solve the shortage. In order to achieve these performances, it has been practiced to construct the building body and the openings such as windows and entrances and exits using an electromagnetic wave shielding material, and to make the whole building an electromagnetic wave shielding structure.

In these electromagnetic wave shielding buildings, the above-mentioned first problems are dealt with by applying an electromagnetic wave shield of 30 dB to 40 dB at 30 MHz to 1 GHz, and the second problem is solved by the important meeting room. In such a case, a high shield such as 80 dB may be required. As the use of multimedia has progressed and the use of wireless systems such as office PHS and wireless LAN has spread in offices, the third problem of congestion in a specific frequency band has been addressed. 30MHz ~
At 3 GHz, a probability of a communication cell of about 20 dB or more is required.

As described above, in order to ensure the sound and reliable operation of OA equipment and wireless systems in a building and to prevent leakage of confidential information, the entire building must be completely shielded from electromagnetic waves with predetermined specifications. Although the frequency band of the electromagnetic wave to be used is not a serious problem when the frequency band of the electromagnetic wave to be used is in the range of 1 to 2 GHz, the frequency band of the electromagnetic wave to be used is 3 to
As the frequency becomes higher, such as 30 GHz, a measure of high dB is naturally required as a measure for shielding electromagnetic waves.

On the other hand, the demand for information communication requires instantaneous transmission and reception of "large-capacity data" and "video" from "call", and information communication has been further increased in order to improve living convenience and business efficiency. There is a tendency to increase the capacity. As one of the measures to meet the demand, the "satellite communication system" has been studied and is being put to practical use. This system launches multiple geosynchronous satellites above the equator and causes radio waves with large capacity and transmission speed of optical fiber class to fall down all over the world.
It seeks to establish the transmission of more information than SDN. In this method, information transmission between satellites is performed by optical communication, and electromagnetic waves reciprocating between the satellite and the ground can carry much more information than conventional satellite communication systems.
An electromagnetic wave in a high frequency band of 30 GHz is used.

As described above, when electromagnetic waves in a high-frequency band are scattered on the ground and the development density of the expanded information communication increases on the ground receiving the electromagnetic waves, it is most important to prevent the electromagnetic waves from being complicated. It will emerge as a theme. And in order to respond to such demands, if the value of the electromagnetic wave shield is steadily increased, the electromagnetic waves of 3 to 30 GHz that are infinitely flying around the building will be completely rejected, as a matter of course. Electromagnetic waves, especially 3 ~
Electromagnetic waves in the frequency band of 10 GHz are reflected on the building, and a large amount of electromagnetic wave disturbance of secondary noise due to reflection is generated around the building.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a means for preventing the structure such as a building shielded from electromagnetic waves from actively reflecting radio waves to the surrounding residents. It is an object of the present invention to provide a non-reflection type electromagnetic wave shielding structure which does not cause electromagnetic wave pollution caused by secondary noise.

[0008]

The present invention is basically a non-reflection type electromagnetic wave shielding structure in which an electromagnetic wave absorber is arranged around a structure except for the direction of arrival of a target electromagnetic wave. Is a non-reflection type electromagnetic wave shielding structure in which an electromagnetic wave absorber is arranged outside a conductive member which is arranged for shielding an electromagnetic wave from entering the structure.
In addition, by arranging such a radio wave absorbing material outside the conductive member arranged for the electromagnetic wave shielding in the building where the electromagnetic wave is shielded, it is possible to completely operate the OA equipment in the building and to prevent the radio wave disturbance to the periphery of the building. For this purpose, an electromagnetic wave absorber is directly provided on the building frame, or the electromagnetic wave absorber is provided while providing a predetermined interior to the building frame. This can also prevent electromagnetic interference caused by secondary noise due to reflection, so that it is possible to completely remove electromagnetic interference from surrounding structures.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a situation where a parabolic antenna is installed on the roof of a building. In this example, building 1
A parabolic antenna 3 for receiving electromagnetic waves 2 of 20 to 30 GHz transmitted from a communication satellite is installed on the rooftop of the building. Since the tower 4 for mounting the parabolic antenna 3 has a considerable scale, electromagnetic waves transmitted from the communication satellite and deviating from the parabolic antenna are reflected on the tower 4 and diffusely reflected to the periphery. This causes electromagnetic interference such as image doubles due to secondary noise in nearby homes and facilities. In addition, since the electromagnetic wave 5 used for general communication equipment also flies in the space vertically and horizontally, when the steel tower 4 as described above is newly constructed, these electromagnetic waves are also repeatedly reflected to the periphery, This will cause radio interference. In order to avoid such radio interference, an enclosure wall 6 equipped with an electromagnetic wave shield and a radio wave absorbing material is installed on the roof of the building around the steel tower 3 according to the present invention. The surrounding wall 6 opens the upper part 7 in the direction of the parabolic antenna 3 facing the direction of the electromagnetic wave sent from the communication satellite as shown in the figure, but the other peripheral part 8 is completely covered.

As described above, the parabolic antenna 3 and its mounted tower 4 covered with the surrounding wall 6 so as to substantially cover the upper portion of the parabolic antenna 3 shield electromagnetic waves from themselves from the outside by the electromagnetic wave shielding function of the surrounding wall 6. Not only does it not interfere with the surrounding area because it is cut off, it also prevents electromagnetic waves coming from various places from being reflected by the electromagnetic wave absorption function of the surrounding wall 6, so that the surrounding area also receives radio waves. There is no obstacle.

The structure of the enclosure 6 is shown in detail in FIGS. The example of the enclosure shown in FIG. 2 employs ferrite 9 as an electromagnetic wave shield and an electromagnetic wave absorbing material.
A plurality of ferrite plates are sandwiched between two polypropylene panels 10, and the periphery is supported by a framework 11. The frame 11 is firmly fixed to the panel 10 with bolts and nuts 13 with a sealing material 12 interposed between the frame 10 and the panel 10. Further, as is apparent from the cross-sectional view, the skeleton is not one kind, and a skeleton 14 in which two skeletons are connected to connect adjacent enclosure walls to each other is also prepared. The ferrites 9 are electrically and magnetically connected to each other, and by electrically grounding the whole having electrical conductivity to the ground, it is possible to exhibit an electromagnetic wave shielding function, and the magnetic performance is improved. In this case, it functions as a radio wave absorber. Panel 7 is made of polypropylene because it is light, has high strength, and is excellent in weather resistance.
As long as the above-mentioned performance conditions are satisfied, it is naturally free to adopt other materials, and there is no limitation.

The example shown in FIG. 3 employs a coated electromagnetic wave absorbing material (Japanese Patent Application No. 8-1648893) 15 which can be sprayed instead of ferrite 9 as an electromagnetic wave shielding and electromagnetic wave absorbing material. The above-mentioned electromagnetic wave absorbing material is sprayed on one side of the panel 10 made of
It is supported by 1. The configuration of the skeleton 11 is the same as that of the ferrite shown in FIG. The coating film electromagnetic wave absorbing material 15 is electrically and magnetically integrated, and it is possible to exhibit an electromagnetic wave shielding function by electrically grounding the whole to the ground. Also in this example, the panel 10 is made of polypropylene because it is light, has high strength, and is excellent in weather resistance, but adoption of other materials is not limited at all. With the above configuration,
Since it is possible to provide the enclosure wall 6 which is extremely lightweight and easy to handle as compared with the conventional electromagnetic wave absorbing material, it is possible to provide a non-reflection type electromagnetic wave shielding structure according to the present invention using this.

Next, an embodiment of the present invention will be described with respect to an example of a building shielded by electromagnetic waves as shown in FIG. In the building 16 of this example, the electromagnetic waves inside and outside the building are shielded from each other with the entire building being completely shielded from electromagnetic waves so as to meet the requirements described in detail in the section of the prior art. Therefore, for various electromagnetic waves flying from the surroundings, a conductor is stretched around the building, and the electromagnetic waves are extremely easily reflected by the conductor. Since the reflected electromagnetic waves cause electromagnetic interference of secondary noise around the building as described above, in order to avoid this, the building 16 is installed in the building as shown in the figure based on the present invention. Of the entire electromagnetic wave absorber 1 outside the shielded electromagnetic wave shield
7 deployments.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The purpose of the arrangement of the electromagnetic wave absorber 17 can be achieved if it is located outside the electromagnetic wave shield, and various methods can be adopted. For example, it is one method to dispose the surrounding wall 6 described in detail in FIGS. 2 and 3 over the entire outer wall of the electromagnetic wave shielding building 16, but in FIGS. 5 to 13, an electromagnetic wave absorber is provided in the building. An embodiment will be described with reference to the drawings.

FIG. 5 shows a construction method in which urethane is sprayed 19 as a base material inside a frame 18 constituting a building, and then an electromagnetic wave absorber 20 is attached. As the electromagnetic wave absorber, the above-described ferrite or the coating film electromagnetic wave absorber is suitable, but other materials having a function as the electromagnetic wave absorber are not limited. Regarding the mounting of the electromagnetic wave absorber, any method such as a mechanical method or a spraying method can be adopted according to the material to be used. After the installation of the electromagnetic wave absorber 20 is completed, a light gauge stud (hereinafter referred to as LG) is formed in accordance with a normal electromagnetic wave shielding method.
(Referred to as S), and a base board 23 and an electromagnetic wave shielding material 24 are stuck thereon, and then a finishing board 25 is attached.
To finish the wall surface neatly.

The embodiment shown in FIG. 6 is a construction method in which an electromagnetic wave absorber 20 is directly attached to the inside of a frame 18 constituting a building and then urethane spraying 19 is performed. Electromagnetic wave absorber 20
After the completion of the urethane spraying work, the usual electromagnetic shielding method is employed as in the example of FIG.

FIG. 7 shows a construction method in which urethane spraying 19 is applied as a base material to the inside of a frame 18 constituting a building, and no electromagnetic wave absorber 20 is attached to this. The electromagnetic wave absorber 20 is equipped with an LGS 21 built at a predetermined distance from the frame 18 and a base board 2 thereon.
3, an electromagnetic wave absorber 20 is attached thereto, and a base board 23 is further attached thereon with an electromagnetic wave shielding material 24, and then a wall surface is formed with a finishing board 25.

FIG. 8 shows a construction method in which, similarly to the embodiment shown in FIG. 7, urethane spray 19 is applied as a base material to the inside of a frame 18 constituting a building, and no electromagnetic wave absorber 20 is attached thereto. Although the LGS 21 is built at a predetermined interval from the frame 18 and the base board 23 is stretched on the LGS 21 and the electromagnetic wave absorber 20 is attached to the LGS 21, the arrangement of the electromagnetic wave shielding material 24 is the same. An example in which an LGS 21 is built at a further predetermined distance from the electromagnetic wave absorber 20, a base board 23 is pasted thereon, an electromagnetic wave shielding material 24 is attached, and then a wall surface is formed by a finishing board 25. It is. The embodiment shown in FIG. 9 is different from the example of FIG. 8 only in that an LGS 21 is built after a base board 23 is provided on the electromagnetic wave absorber 20 to mechanically protect the electromagnetic wave absorber 20.

FIGS. 10 to 13 show an embodiment which is different from the embodiments shown in FIGS. This method is also called the GL method, and is used to attach a base board for finishing the skeleton of a building to a GL such as a resin mortar having a predetermined adhesive strength and holding strength.
This is a base treatment method that uses a bond.

The embodiment shown in FIG. 10 is a construction method in which the electromagnetic wave absorber 20 is directly attached to a building constituting a building by spraying. After the electromagnetic wave absorber 20 has been sprayed, the electromagnetic wave absorber 20 is sprayed with urethane 19, and the base board 23 is bonded thereon using the above-mentioned GL bond 26, and the electromagnetic wave shielding material 24 is attached, and then the finished board 25
Finish the wall surface with.

In the embodiment shown in FIG. 11, the electromagnetic wave absorber 20 and the urethane spray 19 are applied in the same order as in the embodiment of FIG. 10, and then the base board 23 is adhered by using a GL bond 26 to form an electromagnetic wave shielding material. Attach 24. But,
Installation of the finishing board 25 to finish the wall surface is LG
The method of building S21 and performing this is adopted.

In the embodiment shown in FIG. 12, urethane spray 19 is applied to the frame 18 and the GL bond 26 is applied on the urethane spray.
The base board 23 is attached using. Thereafter, the electromagnetic wave absorber 20 and the electromagnetic wave shielding material 24 are attached with the base board sandwiched therebetween as shown in the figure, and the finishing board 25 for forming the wall surface is attached in the same manner as the embodiment of FIG. The LGS 21 is built at an interval from 24, and a method for performing this is adopted.

In the embodiment shown in FIG. 13, urethane spray 19 is applied to the frame 18, a base board 23 is attached on the urethane spray by a GL method using a GL bond 26, and an electromagnetic wave absorber 20 is attached thereon. Further, a base board 23 for protection is arranged. Next, an LGS is built, a base board 23 is stretched over the LGS, and an electromagnetic wave shield 24 and a finishing board 25 are attached. By performing the above-described treatment on the electromagnetic wave shielding structure, 20
Even in the age of abundant use of up to 30 GHz, prevention of confidential leakage electromagnetic waves emitted from structures, prevention of malfunction of OA equipment inside, and ensuring normal operation of wireless LAN etc. are guaranteed, and Even if electromagnetic waves from wireless satellites or high-frequency waves from peripheral devices fly, the structure absorbs the electromagnetic waves and can completely suppress the reflection. Therefore, radio interference may be caused to OA equipment and communication facilities in the surrounding area. Can be prevented.

[0024]

According to the present invention, there is provided a non-reflection type electromagnetic wave shielding structure in which a radio wave absorbing material is arranged around a structure except for a direction in which a target radio wave comes, and an electromagnetic wave shielding structure for preventing electromagnetic waves from entering the structure. Is a non-reflection type electromagnetic wave shielding structure in which a radio wave absorbing material is arranged outside a conductive member arranged for the purpose of the present invention, even if a high frequency of 20 to 30 GHz is used, an obstacle due to secondary high frequency electromagnetic noise Therefore, it is possible to completely eliminate the electromagnetic wave interference around the structure.
Also, in an electromagnetically shielded building, by installing an electromagnetic wave absorber directly on the building frame, or by applying a predetermined interior to the building frame and then installing a radio wave absorbing material outside the electromagnetic wave shielding material, This is an effect that the OA equipment can be completely reliably operated and the radio wave interference around the building can be prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view of a non-reflection type electromagnetic wave shielding structure according to the present invention.

FIG. 2 is a vertical and horizontal sectional view of a steel tower enclosure.

FIG. 3 is a vertical and horizontal sectional view of another steel tower enclosure wall.

FIG. 4 is a perspective view of a non-reflective electromagnetic shielding building according to the present invention.

FIG. 5 is a sectional view showing the construction of the electromagnetic wave absorber.

FIG. 6 is a sectional view showing the construction of another electromagnetic wave absorber.

FIG. 7 is a sectional view showing the construction of another electromagnetic wave absorber.

FIG. 8 is a sectional view showing the construction of another electromagnetic wave absorber.

FIG. 9 is a sectional view showing the construction of another electromagnetic wave absorber.

FIG. 10 is a sectional view showing the construction of another electromagnetic wave absorber.

FIG. 11 is a sectional view showing the construction of another electromagnetic wave absorber.

FIG. 12 is a sectional view showing the construction of another electromagnetic wave absorber.

FIG. 13 is a sectional view showing the construction of another electromagnetic wave absorber.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Building 2 Electromagnetic wave 3 Parabolic antenna Steel tower Electromagnetic wave Enclosure wall 9 Ferrite panel Frame 15 Electromagnetic wave absorber 16 Building 17 Electromagnetic wave absorber 18 Body 19 Urethane spray 20 Electromagnetic wave absorber 23 Base board 24 Electromagnetic wave shield material 25 Finishing board 26 GL bond

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kazuyuki Akeyoshi 12-25, Miyamoto-cho, Shizuoka-shi, Shizuoka Pref.

Claims (5)

[Claims] 1. A non-reflection type electromagnetic wave shielding structure in which an electromagnetic wave absorber is arranged around a structure except for a direction in which a target radio wave comes. 2. A non-reflection type electromagnetic wave shielding structure in which an electromagnetic wave absorber is arranged outside a conductive member arranged to shield an electromagnetic wave from entering a structure. 3. The non-reflection type electromagnetic wave shielding structure according to claim 2, wherein said structure is a building. 4. The non-reflection type electromagnetic wave shielding structure according to claim 2, wherein the structure is a building, and an electromagnetic wave absorber is directly provided on a frame of the building. 5. The non-reflection type electromagnetic wave shield according to claim 2, wherein said structure is a building, and said structure is provided with an electromagnetic wave absorber while providing a predetermined interior to a frame of said building. Structure.