JP6693048B2 - Communication method and communication system - Google Patents

Description

  The present invention relates to a communication method and a communication system.

  When multiple spaces (for example, the upper and lower floors) of a building are partitioned by a shield (for example, floor) that blocks radio waves (a type of electromagnetic wave), wireless communication between these spaces by a radio device Becomes difficult. Therefore, a method is known in which a wiring (such as a television common wiring) that connects a plurality of spaces is provided, a connector and a relay antenna are provided in this wiring, and wireless communication is performed through these (for example, Patent Reference 1).

JP-A-8-125600

  However, in the above communication method, it is necessary to install a relay antenna or a connector in each space. Therefore, there is a problem that it takes time and cost.

  The present invention has been made in view of such conventional problems, and its main object is to easily perform wireless communication.

In order to achieve such an object, the communication method of the present invention is
Communication for performing wireless communication between a first wireless device in the first space and a second wireless device in the second space in a first space and a second space partitioned by a shield that shields electromagnetic waves Method,
A cable that connects the first space and the second space is provided while being insulated from the shield,
An electromagnetic wave emitted from the first radio causes a voltage fluctuation in the cable according to the electromagnetic wave, and a fluctuation of a magnetic field and an electric field generated around the cable due to the voltage fluctuation is caused by the second radio. Received at
A communication method in which an antenna of the first wireless device and an antenna of the second wireless device are respectively brought into contact with the cable ,
The first space and the second space are spaces of a building under construction,
The cable is a temporary power cable,
It is characterized by
According to such a communication method, even if the first space and the second space are partitioned by the shield, wireless communication can be easily performed between the first wireless device and the second wireless device.

In such a communication method, it is preferable that the cable is not provided with a relay antenna and a connector for connecting the cable and the relay antenna.
According to such a communication method, labor and cost can be reduced.

In such a communication method, it is desirable that the periphery of the cable is covered with an insulator, and the conductor is insulated from the shield by the insulator.
According to such a communication method, it is possible to perform wireless communication using the conductor.

  In the communication method, the first space and the second space may be spaces of a building under construction.

In this communication method, the antenna of the first wireless device and the antenna of the second wireless device may be brought close to the conductors to perform the wireless communication.
According to such a communication method, it is possible to easily perform wireless communication by using the conductor by bringing the antenna close to each other.

In this communication method, the shield may be a floor, and the cable may penetrate the floor.
According to such a communication method, it is possible to perform wireless communication in the vertical direction (over the floor).

In this communication method, the shield may be a wall, and the cable may penetrate the wall.
According to such a communication method, horizontal wireless communication can be performed.

Such a communication method, wherein the electromagnetic wave is 920 MH _Z May be

Further, in order to achieve such an object, the communication system of the present invention,
A first radio in the first space,
A second radio in a second space partitioned from the first space by a shield that shields electromagnetic waves;
A cable that connects the first space and the second space while being insulated from the shield,
Equipped with
An electromagnetic wave emitted from the first radio causes a voltage fluctuation in the cable according to the electromagnetic wave, and a fluctuation of a magnetic field and an electric field generated around the cable due to the voltage fluctuation is caused by the second radio. Received at
The antenna of the first radio and the antenna of the second radio are respectively in contact with the cable ,
The first space and the second space are spaces of a building under construction,
The cable is a temporary power cable,
It is characterized by

  According to the present invention, wireless communication can be easily performed.

It is explanatory drawing of the communication method of a comparative example. It is explanatory drawing of the communication method of 1st Embodiment. It is a schematic plan view for explaining the communication method of the second embodiment. It is a schematic plan view for demonstrating the modification of the communication method of 2nd Embodiment.

=== First Embodiment ===
Before describing the present embodiment, a comparative example will be described first.

<About Comparative Example>
FIG. 1 is an explanatory diagram of a communication method of a comparative example.

  The building 1 is a two-story building that is not a wooden structure, and the upper and lower floors (upper and lower spaces) are divided by a floor 3. In the room on the upper floor is a first radio 10 having a wireless communication unit 12 and an antenna 14, and in the room on the lower floor is a second radio 20 having a wireless communication unit 22 and an antenna 24.

  The floor 3 is composed of a deck plate (iron plate) and a reinforcing bar (iron net), and has a property of shielding radio waves (corresponding to electromagnetic waves) (a situation similar to electromagnetic shielding). Therefore, it is difficult to perform good wireless communication (over-floor wireless communication) between the first and second wireless devices 10 and 20 between the upper and lower floors.

  Therefore, in the comparative example, the cable 5 connecting the upper and lower floors is provided through the through hole 4 of the floor 3, and the relay antenna 140 is connected to the cable 5 on the upper floor side via the connector 130. A relay antenna 160 is connected to the cable 5 on the floor side via a connector 150. The connector 130 converts between wireless and wired between the cable 5 and the relay antenna 140. Further, the connector 150 converts between wireless and wired between the cable 5 and the relay antenna 160. The circumference of the cable 5 is covered with an insulator (not shown), and the insulator is electrically insulated from the floor 3.

  As a result, the radio wave emitted from the wireless communication unit 12 of the first wireless device 10 on the upper floor through the antenna 14 is received by the relay antenna 140 and relayed via the connector 130, the cable 5, and the connector 150. The antenna 160 is reached. Then, a radio wave is emitted into the room on the lower floor through the relay antenna 160, and the antenna 24 of the second wireless device 20 receives the radio wave. In this way, the radio waves emitted from the first wireless device 10 can be received by the second wireless device 20. Similarly, the radio wave emitted from the second wireless device 20 is received by the relay antenna 160 and reaches the relay antenna 140 via the connector 150, the cable 5, and the connector 130. Then, a radio wave is emitted into the room on the upper floor through the relay antenna 140, and the antenna 14 of the first wireless device 10 receives the radio wave. In this way, the radio waves emitted from the second wireless device 20 can be received by the first wireless device 10.

  However, in the case of this comparative example, since the connectors 130 and 150 and the relay antennas 140 and 160 are provided in the cable 5 on each floor, there is a problem that it takes time and cost.

  Therefore, in this embodiment, wireless communication can be easily performed.

<About this embodiment>
FIG. 2 is an explanatory diagram of the communication method according to the first embodiment. The same components as those in FIG. 1 are designated by the same reference numerals.

  Also in the present embodiment, similarly to the comparative example, the first radio 10 having the wireless communication unit 12 and the antenna 14 is provided in the room (in the space) on the upper floor of the building 1, and the room on the lower floor is provided. There is a second radio 20 having a wireless communication section 22 and an antenna 24. The upper floor and the lower floor are divided by the floor 3, and a cable 5 connecting the upper floor and the lower floor is provided through the through hole 4 of the floor 3. In addition, as described above, the periphery of the cable 5 is covered with an insulator, and is electrically insulated from the floor 3.

  However, in this embodiment, the connector 130, the relay antenna 140, the connector 150, and the relay antenna 160 as in the comparative example are not provided.

  In such a configuration, in the present embodiment, the antenna 14 of the first wireless device 10 and the antenna 24 of the second wireless device 20 are respectively brought close to the cable 5. By doing so, the radio wave emitted from the antenna 14 of the first radio device 10 causes a voltage fluctuation in the cable 5 according to the radio wave. Then, a high-frequency current flows through the cable 5 due to this voltage fluctuation, and fluctuations in the magnetic field and electric field occur around the cable 5. The fluctuations in the magnetic field and electric field are received by the second wireless device 20 (antenna 24). In other words, the cable 5 functions as an antenna. In addition, conversely, the same applies when the radio waves emitted from the second wireless device 20 are received by the first wireless device 10. As described above, in the present embodiment, since the relay antenna and the connector are not provided, wireless communication can be performed more easily than in the comparative example.

  In the present embodiment, the antenna 14 of the first wireless device 10 and the antenna 24 of the second wireless device 20 are placed close to the cable 5, but the antenna 14 of the first wireless device 10 and the second wireless device By connecting (contacting) the antenna 24 of the machine 20 to the cable 5, the communication sensitivity can be further improved.

  Further, although the upper and lower floors are connected by the cable 5 in this embodiment, the present invention is not limited to this, and any conductor may be used. For example, a telephone line or a pipe (metal pipe) may be used. However, it is necessary that the floor 3 is electrically insulated.

  When the building 1 is a building under construction at a construction site, a temporary power cable can be used as the cable 5. The temporary power cable is for distributing power to each floor (each floor) of the building under construction, and is always provided in the building under construction. Therefore, in this case, the temporary power cable can be effectively used, and labor and cost can be further reduced.

  Further, since the building 1 of the present embodiment is a two-story building, wireless communication was performed between adjacent floors (floors), but the present invention is not limited to this, and wireless communication may be performed at a location separated by a plurality of floors. You can

<Experiment>
Using a test piece (shield) with a through hole of about 10 cm, the transmission of radio waves when the cable is not passed through the through hole and when the antenna of each radio is placed close to the cable by passing the cable through the through hole An experiment was performed to compare the degrees (leakage amounts).

  In the former, almost no radio waves could pass and good wireless communication could not be performed. On the other hand, in the latter case, the improvement was about 40 dB at 2.45 GHz (100 times in electric field strength) and about 60 dB at 920 MHz (1000 times in electric field strength).

  In addition, when the latter was evaluated in a building that was actually under construction, it was possible to communicate from 8 floors away using a temporary power cable.

  As described above, in the communication method of the present embodiment, the antenna 14 of the first wireless device 10 and the antenna 24 of the second wireless device 20 are connected to the cable 5 that connects the upper floor and the lower floor of the building 1. Close to each other. By doing so, the radio wave emitted from the antenna 14 of the first radio device 10 causes a voltage fluctuation corresponding to the radio wave in the cable 5, and the fluctuation of the magnetic field and the electric field generated around the cable 5 due to the voltage fluctuation. Can be received by the antenna 24 of the second wireless device 20. The reverse is also true.

  As a result, in the present embodiment, it is possible to perform wireless communication on the upper and lower floors (wireless communication over the floor) without providing a connector or a relay antenna as in the comparative example. Therefore, in this embodiment, wireless communication can be performed more easily than in the comparative example.

=== Second Embodiment ===
In the first embodiment, upper and lower floors (up and down direction) wireless communication is performed, but in the second embodiment, horizontal direction wireless communication is performed.

  FIG. 3 is a schematic plan view for explaining the communication method of the second embodiment. Note that FIG. 3 is a view of the same floor of the building 100 as seen from above. The building 100 of the second embodiment is also a non-wooden building, and a steel frame or a reinforcing bar is used for the wall 30 that constitutes each room of the building 100. That is, the wall 30 corresponds to a shield that shields radio waves. On the floor of the building 100 shown in the figure, two rooms formed by walls 30 and a corridor 50 outside the two rooms are provided. A cable rack (not shown) is arranged above the corridor 50 along the corridor 50, and a wiring cable 40 is provided in the cable rack.

  As shown in FIG. 3, the first wireless device 10 and the second wireless device 20 are located at an end (a space defined by a wall 30) of a corridor 50 that sandwiches two rooms, and The radio waves emitted from the wireless communication device 10 or the second wireless device 20 are blocked by the wall 30. Therefore, it is difficult to perform wireless communication through the route shown by the dotted line in the figure. Further, since the radio wave has a strong straight traveling property (it is difficult to diffract), it is difficult to perform wireless communication that goes around along the corridor 50. Therefore, in the second embodiment, the antenna 14 of the first wireless device 10 and the antenna 24 of the second wireless device 20 are placed close to the wiring cable 40 provided along the corridor 50. In this case as well, similarly to the first embodiment, wireless communication (here, horizontal wireless communication) can be performed using the wiring cable 40.

  In addition, FIG. 4 is a schematic plan view for explaining a modified example of the communication method of the second embodiment. 4, the same components as those in FIG. 3 are designated by the same reference numerals and the description thereof will be omitted. In this example, small through holes 30a are formed in the plurality of walls 30, and the wiring cable 40 is linearly provided through these through holes 30a. Also in this case, wireless communication can be performed by bringing the antenna 14 of the first wireless device 10 and the antenna 24 of the second wireless device 20 close to the wiring cable 40.

=== Regarding Other Embodiments ===
The above embodiments are for facilitating the understanding of the present invention and are not for limiting the interpretation of the present invention. It goes without saying that the present invention can be modified and improved without departing from the spirit thereof and that the present invention includes equivalents thereof. In particular, the embodiments described below are also included in the present invention.

  In the above-described embodiment, the wireless communication is performed in the space inside the building, but the present invention is not limited to this. For example, it may be a space other than a building such as a vehicle. Further, in the above-described embodiment, the wireless communication is performed using the two wireless devices (the first wireless device 10 and the second wireless device 20), but the present invention is not limited to this, and the wireless communication is divided by, for example, a shield. Wireless devices may be arranged in two or more places (spaces), and wireless communication may be performed using these multiple wireless devices.

1 Building 3 Floor 4 Through Hole 5 Cable 10 First Radio 12 Wireless Communication Unit 14 Antenna 20 Second Radio 22 Wireless Communication Unit 24 Antenna 30 Wall 30a Through Hole 40 Wiring Cable 50 Corridor 100 Building 130 Connector 140 Relay Antenna 150 connector 160 relay antenna

Claims (8)

Communication for performing wireless communication between a first wireless device in the first space and a second wireless device in the second space in a first space and a second space partitioned by a shield that shields electromagnetic waves Method,
A cable that connects the first space and the second space is provided while being insulated from the shield,
An electromagnetic wave emitted from the first radio causes a voltage fluctuation in the cable according to the electromagnetic wave, and a fluctuation of a magnetic field and an electric field generated around the cable due to the voltage fluctuation is caused by the second radio. Received at
A communication method in which an antenna of the first wireless device and an antenna of the second wireless device are respectively brought into contact with the cable ,
The first space and the second space are spaces of a building under construction,
The cable is a temporary power cable,
A communication method characterized by the above. The communication method according to claim 1, wherein
The cable is not provided with a relay antenna, and a connector for connecting the cable and the relay antenna,
A communication method characterized by the above. The communication method according to claim 1 or 2, wherein
The circumference of the cable is covered with an insulator, and the conductor is insulated from the shield by the insulator.
A communication method characterized by the above. The communication method according to claim 3 , wherein
The antenna of the first wireless device and the antenna of the second wireless device are respectively brought close to the conductor to perform the wireless communication.
A communication method characterized by the above. The communication method according to any one of claims 1 to 4 , wherein
The shield is a floor and the cable extends through the floor,
A communication method characterized by the above. The communication method according to any one of claims 1 to 4 , wherein
The shield is a wall and the cable extends through the wall,
A communication method characterized by the above. The communication method according to any one of claims 1 to 6 , wherein:
The electromagnetic wave is 920MH _Z,
A communication method characterized by the above. A first radio in the first space,
A second radio in a second space partitioned from the first space by a shield that shields electromagnetic waves;
A cable that connects the first space and the second space while being insulated from the shield,
Equipped with
An electromagnetic wave emitted from the first radio causes a voltage fluctuation in the cable according to the electromagnetic wave, and a fluctuation of a magnetic field and an electric field generated around the cable due to the voltage fluctuation is caused by the second radio. Received at
The antenna of the first radio and the antenna of the second radio are respectively in contact with the cable ,
The first space and the second space are spaces of a building under construction,
The cable is a temporary power cable,
A communication system characterized by the above.

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