JPS641958B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wireless communication system in a radio wave shielding building in which the space inside the building is electromagnetically shielded from the outside space and the field strength of radio waves leaking into the outside space of the building is below a certain standard.

Generally, when performing wireless communication only within the building using wireless equipment installed inside the building,
Even if the walls of the building are made of concrete that attenuates and shields radio waves, the windows are made of glass that is not electromagnetically shielded, so the radio waves transmitted from outside the building will be transmitted through the windows. enters the building through. Additionally, if the transmission output of a wireless device for intra-building communication installed inside the building is increased, the radio waves will be radiated outside the building because the window glass is not electromagnetically shielded, and the space outside the building will be radiated. interfere with radio waves.

In addition, if the output of the wireless device is a so-called weak radio wave that is not subject to the Radio Law, that is, a radio wave with an electric field strength of 15 microvolts per meter or less at a distance of 100 meters, communication using normal modulation format will not work. A sufficient S/N ratio cannot be obtained and the quality of the call deteriorates. Therefore, it is necessary to have a high-power wireless device licensed under the Radio Law, but to do so, it is necessary to receive frequency allocation for radio waves in the VHF and UHF bands, which are easy to use. The supply and demand situation is so tight that it is difficult to obtain permission to allocate radio waves.

Therefore, due to the above-mentioned reasons, it is undeniable that, at present, there is a slight delay in achieving the function of performing wireless communication only inside a building without requiring communication with the outside of the building.

In view of this point, the present invention provides wireless communication in a radio wave shielding building that has electromagnetic shielding glass as a window part and allows wireless communication in a radio wave shielding building where the interior space and the exterior space are completely cut off and wireless communication is possible only in the interior space. This will be explained in detail below with reference to the drawings.

FIG. 1 is a schematic diagram showing an embodiment of the system of the present invention. In the figure, 1 is a building A made up of concrete exterior walls that shield radio waves.
Since it is assumed that people are doing office work or work on one floor of the building, a window glass section B is provided to let sunlight into the building.

This window glass portion B has a window glass as a component, and the glass plate of the window glass may have a radio wave shielding material formed as a glass surface layer, or the glass material may have a radio wave shielding material formed as a glass surface layer. It is formed by mixing shielding material bodies.

The window glass section B of the building using such window glass allows sunlight to enter the building and blocks radio waves, so if it is necessary to exchange the outside air with the air inside the floor, generally Of course, it is necessary to have a structure in which the windows cannot be opened and closed, and to be equipped with a separate ventilation system. Nowadays, it is common for buildings to be ventilated with the windows closed to provide a sanitary environment for people, so the structure should be such that windows can only be used to let in sunlight and cannot be opened. is easy and not unnatural.

The following glass plate bodies can be used as the window glass to which the present invention is applied.

To form this glass plate for radio wave shielding, ultrafine tin oxide powder or transparent iron oxide ultrafine powder with a diameter of about 0.03 μm is used as a radio wave shielding material and is attached to the surface of the glass plate. By doing so, it is possible to obtain a material that satisfies the transparency required to let in sunlight.

When using a glass having a translucency comparable to that of frosted glass, ultrafine powder with a diameter of about 10 times the diameter of the ultrafine powder may be attached to or mixed with the surface of the glass plate.

In addition, a radio wave shielding paint, such as a nickel-acrylic paint, sprayed onto the surface of a glass plate can also be used as the window glass. The film thickness of this paint is about 70μm, and the frequency is
In the case of 1000MHz, the radio wave attenuation rate is about 25 dB or more, so the radio wave shielding effect is sufficient.

In Fig. 1, 2 is the n fixed antennas (antennas for the central transmission and reception control device) set on the ceiling etc. on the floor, 3 is the central transmission and reception control device placed on each floor, and the device is a radio device. 4. Consists of an operation display section 5 and an exchange distribution connection circuit 6. Also, 7 is a cable or optical fiber, 8 is m
9 is a receiving terminal device, and this 9 includes a pager 9 ₁ , a portable radio telephone 9 ₂ , a radio 9 ₃ and a television 9 ₄ as well as a cordless telephone (rotary dial, (push-button dial), cordless button telephones, facsimile machines, computer terminals, etc. here,
Radios, televisions, facsimile machines, computer terminals, pagers, cordless telephones (cordless telephones, cordless button telephones), portable radio telephones, etc. can be moved and used within the floor.

These terminal devices are also installed on other floors. Communication within the building as referred to in the present invention includes calls and communications within the floor 1 and calls and communications outside the floor. First, calls within the relevant floor 1.
Regarding communication, each terminal 9 ₁ , 9 ₂ , 9 ₃ ,
9 A signal called from ₄ etc. passes through the terminal device antenna 8, is received by the central transmission and reception control device antenna 2, is sent to the central transmission and reception control device 3, passes through the exchange distribution connection circuit 6, and is displayed on the operation display. At the same time as the signal is displayed on the section 5, it is sent to the receiving terminal device 9 through the radio device 4 and the antenna 2, and communication between the terminals becomes possible through this route.

In addition, for communications outside the floor, signals called from each terminal 9 pass through the central transmission/reception control device 3 and are transmitted to other floors via cables or optical fibers 7. Calls and communications can be made using the same method.

Figure 2 is a configuration diagram showing another embodiment in which communication is performed between each floor in a building where the entire building is shielded from radio waves, and includes a transmitting antenna ₁₁₁ installed outside the building and a receiving antenna. The radio waves transmitted and received by the antenna ₁₁₂ are transmitted via the building central control relay device 10 to the central transmission and reception control device 3 similar to that shown in FIG.
Communication with each of the terminals 9 ₁ to 9 _o can be performed via the building antenna. B1F in the same figure indicates the first basement floor. Symbols corresponding to FIG. 1 represent the same functions. Incidentally, it goes without saying that 11 ₁ and 11 ₂ may be used as transmitting/receiving antennas.

FIG. 3 is a schematic diagram showing another embodiment, and shows an embodiment in which there are a plurality of different radio wave shielding devices and all the building spaces are used as a common space. In the figure, 7 is a symbol corresponding to Figures 1 and 2, but in order to use a common space between buildings, cables (metal cables) or optical fibers (or optical cables) 7 are used to connect buildings. There is a connection between them.

Figure 4 is a diagram for explaining the wireless communication system inside a radio wave shielding building, and 7 is a diagram for explaining the wireless communication system inside the radio wave shielding building.
This is a metal cable or optical cable for connecting to the PBX installed in the other radio shielded building shown in the figure. The interface 12 ₁ connects the wireless devices 4 ₁ to 4 _o installed in the building with the radio wave leakage cable 13, and allows communication and phone calls with each of the terminals shown in the figure. It is. The interface 12 ₂ is for interfacing the antennas 11 ₁ and 11 ₂ installed outside the building with the radios 4 ₁ to 4 _o .

The radio waves used in each of the above embodiments are designed to prevent leakage outside the radio wave shielding building, and therefore, the frequency and transmission power of the radio waves used can be freely set as long as the radio waves are within that limited range. .

As is clear from the above description, in accordance with the present invention, as a result of the internal space and external space of the radio wave shielding building being blocked, it is possible not only to freely set the frequency and transmission power as described above, but also to adopt various modulation formats. By establishing a wireless transmission/reception system in radio-shielded buildings, there is no need for wiring to various terminals, and the terminals can be moved freely within the floor to talk and communicate as needed for work, making it possible to use wired transmission/reception systems. On the other hand, the effects of this, combined with lower costs for wiring equipment and construction, are remarkable.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of the method of the present invention, FIGS. 2 and 3 are diagrams showing other embodiments, and FIG. 4 is a diagram showing a wireless communication system in a radio wave-shielded building. It is a figure for explaining. A ...Radio wave shielding building, 1...One floor in building A consisting of a concrete outer wall that blocks radio waves, B...Window glass, 4...Wireless device (or radio device), 9 ...Pocket bell 9 ₁ , a mobile phone 9 ₂ , a radio 9 ₃ , a television 9 ₄ and the like.

Claims (1)

[Claims] 1. Window glass of a building consisting of an external wall made of concrete material that shields radio waves is formed by a glass plate body with a radio wave shielding material formed as a glass surface layer, or by mixing a glass material body with a radio wave shielding material. By constructing a glass plate body, a space is created within the building in which almost no radio waves enter from outside the building, and wireless devices installed inside the building, as well as radios, televisions, and pocket phones inside the building, are 1. A wireless communication system in a radio wave shielding building, characterized in that communication is carried out inside the building using a cordless telephone, a mobile radio telephone, etc., and leakage of radio waves to the outside of the building is eliminated.