JPH0362319B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides inter-floor electromagnetic shielding suitable for dividing an electromagnetic shielding space into each floor and adopting an information network system using radio waves on each floor. Regarding the method.

[Conventional technology]

Generally, in intelligent buildings, information communication equipment such as multi-purpose electronic exchanges and computers is shared to communicate information within the building and with the outside world. The amount of information is increasing. Under such circumstances, the challenge in intelligent buildings is how to transmit necessary information more quickly and at a lower cost. To address these issues in intelligent buildings, information networks based on the data highway system using optical fiber cables and coaxial cables have been studied and proposed.

[Problem that the invention seeks to solve]

However, with the data highway method that uses fiber optic cables and coaxial cables, fiber optic cables and coaxial cables must be laid out to every corner (terminal equipment) in an intelligent building, and the cables must be installed on the floor. Ducts and a double floor structure are required, making construction cost and construction time an issue.

Furthermore, if radio waves are used for information communication within a building, there is no need to lay cables, but on the other hand, frequencies up to 50 GHz are subject to regulations under the Radio Law because they emit noise radio waves to the outside. A problem arises in that the system malfunctions due to external radio waves or the like.

Therefore, the applicant proposes an intelligent building that enables communication within the building by radio waves by making the entire building an electromagnetic shielding structure by using electromagnetic shielding materials in the frame and openings such as windows and doorways. We are doing various things. However, when communicating using radio waves in such an intelligent building, if n-channel frequency bands are allocated to each floor, a building with m floors will require n×m-channel frequency bands. Therefore, if the frequency bandwidth of each channel is 25 kHz, the required frequency bandwidth when the entire building is treated as one electromagnetic shield space is 25 kHz x n x m. For this reason, as buildings become taller and the amount of traffic increases, the required frequency bandwidth (the number of channels required) expands, and communication equipment becomes larger and equipment costs become more expensive. . One possible method to solve this problem is to further divide the electromagnetic shielded space within the building. However, while electromagnetic shielding performance can be easily ensured on ceilings and floors by using electromagnetic shielding materials, ensuring electromagnetic shielding performance at staircases where the space is continuous becomes a problem.

The present invention solves the above-mentioned problems, and aims to provide an inter-floor electromagnetic shielding method that makes it possible to configure individual electromagnetic shielding spaces for each floor.

[Means for solving problems]

To this end, the present invention makes it possible to communicate information using radio waves within a building by using electromagnetic shielding material in the building frame and openings such as windows and doorways in the building frame to provide electromagnetic shielding from the outside. In an intelligent building, electromagnetic shielding materials are used on the floor or ceiling to provide electromagnetic shielding between the upper and lower floors, and the space for stairways connecting each floor is reduced using isolation walls whose inner surfaces are covered with radio wave absorbers. A staircase is enclosed to form a staircase, a separation wall covered with a radio wave absorber is provided in the center of the staircase, and stairs are arranged around the separation wall to form an electromagnetic shielding space for each floor. It is.

[Effect]

In the intelligent building of the present invention, electromagnetic shielding material is used in the frame and openings such as windows and doorways of the frame to provide electromagnetic shielding from the outside, and electromagnetic shielding material is used on the floor or ceiling. Since electromagnetic shielding is provided even between floors, it is possible to create an electromagnetic shielding space on each floor, and information communication using radio waves can be performed on each floor without being affected by radio waves from other floors.
In this case, the staircase that connects the floors becomes the opening,
If there is radio waves going back and forth between floors, interference will occur if the same frequency is used on each floor, so it becomes necessary to allocate different frequencies to each floor, treating the building as one space. However, a separation wall whose inner surface is covered with a radio wave absorber is used to enclose the space where the stairs connecting each floor are arranged to form a staircase room, and a separation wall covered with a radio wave absorber is provided in the center of the staircase room. Since the stairs are arranged so as to go around the stairs, in the staircase room, the radio waves cannot pass through to other floors unless they are reflected by at least the isolation wall and the separation wall. Therefore, by using a radio wave absorber here, the radio waves are absorbed and attenuated, and the radio waves are absorbed and attenuated. It is possible to prevent radio waves from passing between the two.

〔Example〕

Examples will be described below with reference to the drawings.

FIG. 1 is a diagram showing one embodiment of the electromagnetic shielding structure for a stairwell according to the present invention, and FIG. 2 is a diagram showing another embodiment of the electromagnetic shielding structure for a stairwell according to the present invention. In the figure, 1 and 7 are stairs, 2 is a landing, 3 is a radio wave absorber, 4 is a central separation wall, 5, 6, 9 and 10 are staircase compartment separation walls, and 8 is a pole.

In FIG. 1, the stairway is partitioned around the stairway by stairway separation walls 5 and 6, and furthermore, a central separation wall 4 is disposed in the center. FIG. 1a shows a plan view thereof, and FIG. 1b shows a sectional view taken along line A-A' in FIG. 1a. In the example shown in FIG. 1, the basic structure of the staircase 1 is a type of spiral staircase that ascends to the upper floor via a landing 2 with a central separation wall 4 in between. The central separation wall 4 extends to the upper floor and separates the stair space on the floor below the landing 2 from the stair space on the upper floor. In addition to using electromagnetic shielding materials, radio wave absorbers 3 are also used on the walls. Therefore, radio waves that enter the stairwell from each floor will be reflected on the wall of the stairway, bypass this space, and leak to other floors, but the walls of the stairway isolation walls 5 and 6 and the central separation wall 4 Since the radio waves are attenuated by the radio wave absorber, there is no radio wave leakage between the upper and lower floors.

FIG. 2 shows an example of a pure spiral staircase with a cylindrical pole 8 placed in the center. Second
In the example shown in the figure as well, electromagnetic shielding materials are used for the pole 8 and stair isolation walls 9 and 10, and radio wave absorbers are also used for the walls, floor, ceiling, etc. The radio waves that enter the staircase from each floor must be wrapped around the cylindrical pole 8 and passed through the space above the staircase 7 while repeatedly reflecting off walls and floors, etc., in order to leak to other floors. It can be attenuated by radio wave absorbers on the walls of the room isolation walls 9 and 10 and the pole 8, and furthermore, radio wave absorbers on the stairs, floor, and ceiling.

Next, the reflection of radio waves in the staircase and the attenuation effect by the radio wave absorber will be specifically explained.

For example, in FIG. 1a, radio waves incident from the entrance on the lower right side of the figure are reflected by the inner surface of the staircase partition wall 6 or the center partition wall 4. Radio waves that have been reflected once on the inner surface on the right side in the illustration of the staircase isolation wall 6 and directly entered the inner surface on the upper side in the illustration or directly enter the inner surface on the upper side in the illustration are transmitted to the landing 2.
The reflection with the central separation wall 4 is repeated up to the point. Similarly, the radio waves directly entering the central separation wall 4 are repeatedly reflected on the inner surface of the staircase separation wall 5 up to the landing 2. Then, the radio waves are reflected to the opposite side (from top to bottom, bottom to top) at the landing 2 on the inner surface of the left side of the stairway separation walls 5 and 6 in the figure, and then repeat the same reflection to reach the other floor (upper reaching the entrance of the floor or lower floor). By repeating reflections in this way, radio waves attenuate according to the reflection coefficient.

Examples of radio wave absorbers include dielectric absorbers such as resistive cortex, carbon rubber, fibers with carbon attached, carbon-containing urethane foam, and graphite-containing polystyrene foam, and magnetic absorbers such as ferrite plates lined with metal plates. (``Electronic Communication Handbook'', edited by the Institute of Electronics and Communication Engineers, Ohmsha Co., Ltd., 1st edition, 5th printing, published on February 20, 1985, p. 1546).
Generally, there is no clear standard value for the reflection coefficient of radio wave absorbers, but it is set to be between -20 dB and -30 dB. Therefore, if a radio wave absorber is used, a considerable amount of radio wave attenuation can be expected with just one reflection, and if a separation wall is installed in the center and the reflection is repeated multiple times, it is possible to reduce the amount of radio waves from the staircase. can almost eliminate radio wave leakage.

The attenuation of radio waves due to reflection is as follows: When the incident radio wave intensity is A and the reflection coefficient is α (0<α<1), the radio wave intensity A' after reflection is A'=αA. Therefore, the radio wave intensity A ⁿ ′ after repeating n reflections is A ⁿ ′=α ⁿ A. For example, if a radio wave absorber is used on all surfaces visible from each entrance, the radio wave can be attenuated by the radio wave absorber at least once, and the radio wave that enters from that entrance and is reflected once will not reach the other entrance. By providing a separation wall like this, the radio waves can be attenuated by the radio wave absorber at least twice. Of course, not only walls but also stairs, floors, and ceilings serve as reflective surfaces for radio waves, so by using a radio wave absorber on the entire inside surface and increasing the number of reflections in the staircase, the attenuation effect can be further enhanced. In this sense, it goes without saying that there is a certain range of ranges in which the radio wave absorber is used, from the configuration in which the wave is reflected at least once by the radio wave absorber as described above to the configuration in which it is used on the entire inside surface.

Next, an example of an electromagnetic shielding ceiling system that can divide an electromagnetic shielding space by the ceiling of each floor by combining with the electromagnetic shielding structure for a staircase according to the present invention will be described.

Figure 3 is a diagram showing an example of a special T-bar with built-in antenna applied to an electromagnetic shielding ceiling system, Figure 4
The figure shows the entire ceiling with an electromagnetic shielding structure and an antenna built into the room.
In the figure, 11 is a field edge, 12 is a T-bar receiver, 13 is a special T-bar, 14 is a ceiling board, 15 is an electromagnetic shielding material, 1
6 is a lighting equipment, 17 is an antenna, 18 is a conductive material,
19 is an insulating material, 21 is a slab, 22 is a hanging bolt, 23 is a frame reinforcement, 24 is a frame, 25 is a connecting wire, 26 is an air conditioning duct, and 27 is a filter.

In FIG. 3, the ceiling structure material 11 is suspended from the slab with hanging bolts, and the ceiling base support edge 12 is fixed to this ceiling structure material 11 and supports the special T-bar 13. . As shown in the figure, the special T-bar 13 supports a ceiling plate 14, a lighting fixture 16, etc., and also allows an antenna 17 for wireless communication to be installed inside the room.
By incorporating an antenna 17 into the indoor side of this special T-bar 13 and configuring the ceiling with a ceiling plate 14 and lighting fixtures 16 that have electromagnetic shielding performance, the electromagnetic shielding space can be divided into each floor. Wireless communication can be performed by allocating a frequency band.
The electromagnetic shielding material 15 of the ceiling board 14 is a special T-bar 13
By using a conductive material 18 at the seam portion, electrical connection can be established between the two. Further, the antenna 17 may be installed while being insulated from the special T-bar 13 using an insulating material 19. Note that as the antenna 17, a leaky coaxial cable, a waveguide, or the like can be used.

Figure 2 shows the entire ceiling with an electromagnetic shielding structure using the above-mentioned ceiling board and special T-bar, and an antenna built into the indoor side. In Fig. 2, a louver with an electromagnetic shielding effect is used for the lighting equipment 16, and an air conditioning duct 2 is used.
A conductive mesh filter 27 is fitted into the opening 6. By connecting the louver and the special T-bar 13 with the connecting wire 25, it can be electrically integrated with the ceiling plate 14, or by connecting the special T-bar 13 and the filter 27 with a conductive material or direct contact. Therefore, it is electrically integrated, and reinforcing bar 2
3 to ground, the entire ceiling surface has electromagnetic shielding performance. As a result, the room is shielded from, for example, the ballast of lighting equipment and other power equipment placed in the ceiling, and it is also possible to prevent malfunctions of communication equipment in the room due to these noises.

The antenna built into the ceiling as described above can be used for wireless communication between communication devices installed on each floor by connecting it to a coaxial cable via a branch. In addition, the coaxial cable used for common television viewing through EPS can be used.
In this way, by creating a structure that has electromagnetic shielding performance not only for the building frame but also for each floor, malfunctions due to leakage radio waves and noise from the outside and other floors are eliminated, and N-channel frequency bands are assigned to each floor. , wireless communication using the same n-channel frequency bandwidth of 25 kHz x n is possible for each floor regardless of the number of floors. Furthermore, radio waves in any economically advantageous frequency band can be used regardless of regulations under the Radio Law.

Note that the present invention can be modified in various ways and is not limited to the above embodiments. As is clear from the above embodiments, the electromagnetic shielding structure for a staircase according to the present invention reflects radio waves entering the staircase on the walls, floor, and ceiling of the staircase, and attenuates the radio waves using a radio wave absorber. It is something that makes you Therefore, basically, the shape of the staircase, the arrangement of the entrance, and the shape of the internal separation wall are designed so that the radio waves that enter the staircase do not directly leak to other floors and are attenuated by the radio wave absorber. Of course, various modifications can be made to the arrangement, etc. Furthermore, electromagnetic shielding performance can be further improved by using radio wave absorbers on stairs, floors, and ceilings.

〔Effect of the invention〕

As is clear from the above explanation, according to the present invention, each floor can be divided into electromagnetic shielding spaces.
The same frequency band can be selected for each floor. Therefore, communication equipment with the necessary frequency bandwidth can be provided for each floor of the entire building, regardless of the number of floors. Moreover, since the same frequency band can be used on each floor, communication equipment with the same specifications can be used on each floor, making it possible to standardize communication equipment and reduce equipment costs.

[Brief explanation of drawings]

FIG. 1 is a diagram showing one embodiment of the electromagnetic shielding structure for a stairwell according to the present invention, FIG. 2 is a diagram showing another embodiment of the electromagnetic shielding structure for a stairwell according to the present invention, and FIG. FIG. 4 is a diagram illustrating an example of a special T-bar with built-in antenna applied to a shielding ceiling system. FIG. 4 is a diagram showing the entire ceiling in which the entire ceiling has an electromagnetic shielding structure and an antenna is incorporated inside the room. 1 and 7... stairs, 2... landing, 3... radio wave absorber,
4... Central separation wall, 5, 6, 9 and 10... Staircase separation wall, 8... Pole, 11... Edge, 12... T-bar holder, 13... Special T-bar, 14... Ceiling board, 15... Electromagnetic shielding material , 16...Lighting equipment, 17...Antenna, 1
8... Conductive material, 19... Insulating material, 21... Slab, 22
...Hanging bolt, 23...Structure reinforcing bar, 24...Structure, 2
5... Crossover connection wire, 26... Air conditioning duct, 27... Filter.

Claims (1)

[Claims] 1. In an intelligent building that uses electromagnetic shielding materials in the frame and openings of the frame such as windows and doorways to provide electromagnetic shielding from the outside, making it possible to communicate information using radio waves within the building. Electromagnetic shielding material is used on the floor or ceiling to provide electromagnetic shielding between the upper and lower floors, and an isolation wall whose inner surface is covered with a radio wave absorber is used to enclose the space where the stairs connecting each floor are arranged to be used as a staircase room. An inter-floor electromagnetic shielding method, characterized in that a separation wall covered with a radio wave absorber is provided in the center of the stairway, and stairs are arranged so as to go around the separation wall, thereby configuring an electromagnetic shielding space for each floor.