JP2581608B2 - Radio relay for indoor wireless communication - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a wireless communication between two persons, at least one of which moves in a large building having a floor, a wall, and a partition for shielding radio waves. The present invention relates to a radio repeater for wireless communication in a building for enabling wireless communication regardless of the presence of the radio wave shield.

[Prior Art] In recent years, larger and larger buildings have been built, and a number of information processing apparatuses or OA equipments have been connected to each other to form a so-called system. Systems must always be carefully maintained to keep them in good working order.

In the above-mentioned maintenance work, for example, in the case of starting the site adjustment at the time of installation and taking measures for trouble, etc., it is often necessary for the maintenance workers to be in each of a plurality of places and work while communicating with each other. In such a case, the telephone facilities in the existing building may be available, but there are places where telephones are not installed, and telephones installed for other work should be dedicated for maintenance work. Is often impossible, even temporarily. Therefore, since the maintenance worker needs to communicate with each other between unspecified plural places, it is desirable that each of them be contacted by a dedicated wireless communication device. Usually, for this purpose, it is categorized as simple wireless according to the Radio Law.For example, in the 150 MHz band or 450 MHz band, the qualification of a wireless worker is limited to a small number of fixed and mobile wireless sets that transmit and receive each other for each area. Instead of being approved even if it is not approved, a wireless communication device of a system that is subject to various regulations in order to jointly and efficiently use radio waves, such as antenna power, antenna height, and talk time, seems to be appropriate.

[Problems to be solved by the invention] However, the thick floors and walls of concrete in which steel frames and reinforcing bars are embedded in today's buildings hardly allow radio waves to pass, and removable partition walls, such as sound insulation. For this reason, when the floor is closed from the ceiling to the ceiling, radio waves are shielded because a steel plate is usually used as a material. Since ordinary glass windows allow radio waves to pass through relatively well, according to the results of experiments by the present inventors, rooms facing the outside of the building, even between floors far apart, may have a nearby adjacent building. Wireless communication was possible, but between rooms surrounded by walls, metal partitions, etc. inside the building, these radio wave shields attenuated, for example, 50 dB or more, and communication was not possible with simple radios Met. As can be understood from the application, a large and heavy wireless device with high performance is difficult to use for such a purpose, and it is difficult to solve the problem by improving the performance of the wireless communication device itself.

The present invention, as described above, attempts to communicate with each other.
If at least one of the rooms is surrounded by a radio wave shield that blocks radio communication radio waves and makes it impossible to communicate, place the radio wave shield in between and install An object of the present invention is to provide a radio repeater for wireless communication in a building that enables wireless communication without being hindered.

[Means for Solving the Problems] In order to achieve the above object, according to the present invention, in a building having a floor, a wall, and a partition for shielding radio waves, each room on both sides separated by the radio wave shield, An antenna suitable for transmitting and receiving radio waves for wireless communication to be used is installed, and a coaxial cable is passed between the antennas on both sides through a through hole formed in the radio wave shield, and both ends of the coaxial cable and the antennas on both sides respectively. A connector is attached to the supporting portion of the camera, and the connector is detachably connected and connected through these connectors.

[Operation] When installing the radio wave repeater according to the present invention, a through hole must be formed in a radio wave shield in a building that causes radio interference, but the hole diameter is at most about 2 cm. Therefore, there is no possibility that another problem will be caused by providing the through hole. Since no active element is used at all, there is no particular problem in selecting an installation location and the like, but rather it may be freely installed in a position where a through hole is easily provided. In addition, since it has a very simple configuration and requires no adjustment or the like, it can be made very inexpensively and can be easily mounted. The strength of the radio wave received by the antenna may vary considerably depending on the mounting position and mounting state of the antenna, but since the detachable connector is used in the middle, the mounting conditions are changed appropriately and the sensitivity is easily improved. There is no problem because it can be in a state.

Embodiment FIG. 1 is a schematic explanatory view of one embodiment of the present invention, in which 1 is a radio wave shield, 2 is an antenna, 3 is a coaxial cable, and 6 is a connector. The antenna 2 is a cylindrical conductor having a total length of λ / 2 (where λ is the used wavelength), and feeds power at the center (each side is λ / 4).

FIG. 2 (a) is a diagram for explaining a conventional state in which wireless communication is impossible when the electric wave is blocked by a radio wave shielding object. For example, an electric field of 50 dB or more is attenuated and is used in this case. Communication is not possible with a small simple wireless device. On the other hand, FIG. 2 (b) is a diagram for explaining a state when the radio wave repeater of the present invention is installed. The attenuation of the electric field is reduced to about 20 dB, and communication is possible even with a small simple wireless device. .

[Effects of the Invention] As described above, according to the present invention, an extremely simple and inexpensive device can be used even in a building having a floor, a wall, and a partition for shielding radio waves while using a small and lightweight simple wireless device. Wireless communication becomes possible.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of one embodiment of the present invention, FIG. 2 (a) is a view for explaining a conventional state where radio communication is impossible as it is interrupted by a radio wave shield, and FIG. It is a figure explaining the state at the time of installing an invention electric wave repeater. 1 ... radio wave shield, 2 ... antenna 3 ... coaxial cable, 4 ... maintenance worker 5 ... simple radio, 6 ... connector

Claims (1)

(57) [Claims] An antenna suitable for transmitting and receiving a radio wave for wireless communication to be used is installed in each of rooms on both sides separated by the radio wave shield in a building having a floor, a wall, and a partition for shielding a radio wave, A coaxial cable is passed between the antennas on both sides through a through hole formed in the radio wave shield, and connectors are attached to both ends of the coaxial cable and the support portions of the antennas on both sides, and are detachable via these connectors. A radio repeater for wireless communication in a building, which is connected to and connected to a radio wave.