JP2017227485A - Flooding detection system and flooding detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flooding detection system and a flooding detection method for preventing a burden increase of a wiring work.SOLUTION: A flooding detection system 10 comprises: a wireless device 100; a communication device 200 which can radio communicate with the wireless device 100; and a flooding determination part 310 for determining a flooding state on a point where the wireless device 100 is installed, based on radio field intensity of a signal which one of the wireless device 100 and the communication device 200 received from the other device. The flooding detection method comprises: a step in which the wireless device 100 and the communication device 200 perform radio communication; and a step for, based on radio field intensity of the signal which one of the wireless device 100 and the communication device 200 received from the other device, determining a flooding state on the point where the wireless device 100 is installed.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a flood detection system and a flood detection method.

Conventionally, a technique for detecting inundation in a manhole is known (for example, see Patent Document 1). On the other hand, inundation damage due to localized torrential rain caused by weather phenomena such as the heat island phenomenon has occurred. In order to give appropriate evacuation instructions, it is necessary to detect inundation as soon as possible. Currently, a system has been proposed in which a sensor having two exposed electrodes is provided in a drainage groove, and the inundation is detected by short-circuiting between the electrodes due to the inundation.
[Prior art documents]
[Patent Literature]
[Patent Document 1] JP 2010-138679 A

  In the above system, the burden of wiring work for the sensor increases.

  In a first aspect of the invention, a flood detection system is provided. The inundation detection system may include a wireless device, a communication device, and an inundation determination unit. The communication device may be capable of wireless communication with the wireless device. The inundation determination unit may determine the inundation situation at the point where the wireless device is installed based on the radio field intensity of the signal received by one of the wireless device and the communication device from the other device.

  As the wireless device is submerged, the wireless device may stop transmitting signals. The inundation determination unit may determine that the point where the wireless device is installed is inundated by detecting the stop of transmission of a signal from the wireless device.

  The wireless device may be accommodated in a housing. The housing may be waterproofed. The inundation determination unit may determine that the water level around the wireless device is higher as the radio wave intensity is lower.

  The inundation determination unit may calculate the change speed of the water level based on the time change of the radio wave intensity.

  The wireless device may further include a sensor unit. The sensor unit may detect a physical quantity. The wireless device may transmit the detection result of the physical quantity by the sensor unit in a state where the wireless device is not flooded.

  The inundation detection system may include a plurality of types of wireless devices. Multiple types of wireless devices may have different sensors for detecting different physical quantities.

  The wireless device may have a pressure sensor. The inundation determination unit may determine the inundation situation by using the change in the radio wave intensity and the detection result of the pressure sensor in combination.

  The inundation detection system may further include a selection unit. The selection unit may select a guide path to an area with less flooding based on the determination result of the flooding situation.

  The inundation detection system may include a plurality of wireless devices. The inundation determination unit may determine the inundation status at each point where each wireless device is installed. The selection unit may select the guide path based on the inundation start time of each wireless device.

  The plurality of wireless devices may include a plurality of wireless devices arranged at different heights.

  The inundation detection system may further include a water stop plate control unit. The water stop plate control unit may control the water stop plate for stopping the expansion of the water based on the determination result of the water infiltration state.

  The inundation detection system may include a plurality of wireless devices and a plurality of communication devices. A plurality of communication devices may constitute a multi-hop wireless mesh network.

  The inundation detection system may include a plurality of wireless devices and an acquisition unit. The acquisition unit may acquire related information related to flooding. The plurality of wireless devices may include a switching unit. The switching unit may switch the operation mode of the plurality of wireless devices based on the related information.

  The switching unit may switch the operation mode to a mode in which a plurality of wireless devices can mutually perform multi-hop wireless mesh communication based on the related information.

  The switching unit may switch the operation mode based on the related information to a mode in which each wireless device communicates with the communication device more frequently than when the acquiring unit has not acquired the related information.

  In a second aspect of the present invention, a flood detection method is provided. The inundation detection method may include a step of performing wireless communication and a step of determining the inundation state. The step of performing wireless communication may be wireless communication between the wireless device and the communication device. The step of determining the inundation status may determine the inundation status at the point where the wireless device is installed based on the radio wave intensity of the signal received by one of the wireless device and the communication device from the other device.

  It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

It is a figure explaining the outline | summary of the inundation detection system 10 in 1st Embodiment. It is a figure which shows an example of a structure of the radio | wireless apparatus 100 in 1st Embodiment. It is a figure which shows an example of a structure of the repeater. 3 is a diagram illustrating an example of a configuration of a parent device 250. FIG. It is a flowchart which shows the process of the inundation detection system 10 in 1st Embodiment. It is a flowchart which shows an example of a guidance route selection process. It is a flowchart which shows the process of the inundation detection system 10 in 2nd Embodiment. It is a figure explaining the outline | summary of the inundation detection system 10 in 3rd Embodiment. It is a figure which shows an example of a structure of the radio | wireless apparatus 150 in 3rd Embodiment. It is a flowchart which shows the process of the inundation detection system 10 in 3rd Embodiment. It is a flowchart which shows an example of a guidance route selection process. It is a flowchart which shows the other example of a guidance route selection process. It is a flowchart which shows the process of the inundation detection system 10 in 4th Embodiment. It is a flowchart which shows the process of the inundation detection system 10 in 5th Embodiment. It is a flowchart which shows the process of the inundation detection system 10 in 6th Embodiment. It is a figure explaining the outline | summary of the inundation detection system 10 in 7th Embodiment. It is a figure which shows an example of a structure of the radio | wireless apparatus 170 in 7th Embodiment. It is a flowchart which shows a process when inundation relevant information is acquired in the inundation detection system 10 in 7th Embodiment. It is a flowchart which shows an example of an operation mode switching process. It is a flowchart which shows the other example of an operation mode switching process.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 is a diagram for explaining the outline of the inundation detection system 10 according to the first embodiment. The inundation detection system 10 of this example includes wireless devices 100a, 100b, 100c, 100d, and 100e. The inundation detection system 10 of this example includes a repeater 200a, a repeater 200b, and a repeater 200c. The inundation detection system 10 of this example includes one master unit 250. However, the numbers and types of the wireless device 100, the repeater 200, and the parent device 250 are not limited to this case. In the following description, the wireless devices 100a to 100e may be collectively referred to as the wireless device 100, and the repeaters 200a to 200c may be collectively referred to as the repeater 200.

  The repeater 200 and the parent device 250 are communication devices that can wirelessly communicate with the wireless device 100. However, unlike this example, the inundation detection system 10 may include only one of the repeater 200 and the parent device 250 as a communication device. The inundation detection system 10 of this example may further include a server computer 300 that can be connected to the repeater 200 or the parent device 250 and the communication network line 6. The wireless device 100 is installed at a point to be monitored for flooding. For example, when monitoring the inundation of an underground passage, a plurality of wireless devices 100 are installed along the passage so as to reach a predetermined height from the reference plane 2. The reference surface 2 may be a lower surface or a floor surface of the structure to be monitored.

  In the drawings, the vertical and horizontal scales are changed for the sake of explanation. The adjacent wireless devices 100 may be separated from each other by several meters to several tens of meters, or several hundreds of meters. Similarly, the adjacent repeaters 200 may be separated by the same distance.

  A plurality of wireless devices 100 arranged at different heights H1 and H2 such as the wireless device 100d and the wireless device 100e may be included. A plurality of wireless devices 100 installed at different heights H1 and H2 may be included in each point where the wireless devices 100a, 100b, and 100c are disposed as well as the point where the wireless device 100d is disposed. In addition, the wireless device 100 is not limited to being installed at two different heights H1 and H2, and may be installed at three or more different heights. On the other hand, repeater 200 and base unit 250 may be installed at a position higher than wireless device 100. For example, the repeater 200 and the master unit 250 are installed in a place where there is little possibility of being submerged, such as the ceiling 4 of the structure or the upper part of the side wall.

  The inundation detection system 10 may include a plurality of types of wireless devices 100. In this example, the inundation detection system 10 includes a wireless device 100a that does not have a sensor unit, and wireless devices 100b to 100e that have a sensor unit. In this example, the wireless device 100b and the wireless devices 100c to 100e have different sensors for detecting different physical quantities. Specifically, the wireless device 100b may include a temperature sensor and a humidity sensor 114, and the wireless device 100c to the wireless device 100e may include a pressure sensor 112.

  However, unlike the present embodiment, the plurality of wireless devices 100 included in the inundation detection system 10 may be of the same type. The wireless devices 100 may all have the same type of sensor unit. Each of wireless devices 100 communicates with repeater 200 or base unit 250 at a predetermined communication frequency. The wireless device 100 may periodically communicate at a predetermined communication interval such as every minute. The signal transmitted by the wireless device 100 may include identification information for identifying the device from other devices. However, when there is one wireless device 100, it is not necessary to identify from other devices, and thus identification information may not be included.

  The wireless device 100 may stop transmitting signals as it is submerged. For example, the housing 102 of the wireless device 100 has an opening 104. When the wireless device 100 is submerged, water flows into the wireless device 100 through the opening 104, and transmission of signals stops with the inflow of water.

  Repeater 200 transfers the received signal to base unit 250. When the received signal includes the identification information of the wireless device 100, the signal including the identification information may be transferred to the parent device 250. The repeaters 200a to 200c and the parent device 250, that is, the plurality of communication devices may constitute a multi-hop wireless mesh network.

  Each of the wireless devices 100a to 100e may communicate with at least one of the repeaters 200a to 200c. A signal transmitted from the wireless device 100a to the wireless device 100e may be transmitted to the parent device 250 via one or more of the plurality of repeaters 200a to 200c. Each of the wireless devices 100a to 100e may directly communicate with the parent device 250 without passing through the repeaters 200a to 200c.

  According to the multi-hop wireless mesh network, a plurality of candidates are provided as communication paths from a specific wireless device 100 to the parent device 250, and a route with the best communication state is selected from the plurality of candidates. Even if a path that has become unable to communicate due to a communication failure or the like occurs, a signal is transferred until the master unit 250 that is the transmission destination is reached by reconstructing another path. For example, the wireless device 100e communicates with the repeater 200a having a short distance, but communicates with another repeater 200b when the communication state with the repeater 200a is deteriorated due to a communication failure or the like.

  Therefore, the multi-hop wireless mesh network can transmit a signal to the base unit 250 even under a situation where the communication state is not good. As such a multi-hop wireless mesh network, the IEEE 802.15.4g standard may be applied mutatis mutandis. However, the multi-hop wireless mesh network is not limited to this standard.

  Master device 250 may be connected to communication network line 6. In this example, base unit 250 is communicably connected to server computer 300 through communication network line 6. The communication network line 6 is, for example, Ethernet (registered trademark). The server computer 300 of this example includes a flood determination unit 310, an acquisition unit 320, an air conditioning control unit 330, a storage unit 340, a selection unit 350, and a water stop plate control unit 360. The inundation determination unit 310 determines the inundation status at the point where the wireless device 100 is installed based on the radio field intensity of the signal received by one device of the wireless device 100 and the repeater 200 (or the parent device 250) from the other device. to decide.

  In this specification, to determine the inundation status based on the radio field intensity of the signal, to determine the inundation status based on whether the radio field intensity is zero, that is, based on the presence or absence of a received signal, Determining the situation may be included. In this example, the inundation determination unit 310 determines that the point where the wireless device 100a to the wireless device 100e is installed has been submerged by detecting the stop of transmission of signals from the wireless device 100a to the wireless device 100e. The acquisition unit 320 may include an interface for connecting to the communication network line 6. The acquisition unit 320 may communicate with the external server 370 through the communication network line 6.

  The air conditioning control unit 330 controls air conditioning at a point where the wireless device 100 is provided based on the detection result of the physical quantity by the wireless device 100. The physical quantity may include temperature, humidity, illuminance, or pressure. For example, the air conditioning control unit 330 transmits control information to an external air conditioning equipment server 332 via the communication network line 6. The inundation detection system 10 of the present embodiment can be used as another control system such as an air-conditioning control system in normal times when it is not inundated. Or, conversely, another control system such as an air conditioning control system can be used as the inundation detection system 10 during inundation.

  The storage unit 340 stores various information and tables. A table that associates the identification information of each of the wireless devices 100a to 100e and the installation position information, map data (map information), and information on the taxiway may be stored in the storage unit 340 in advance. The installation position information may include information on the height at which the wireless devices 100a to 100e are installed.

  The selection unit 350 selects a guide path to a region with less flooding based on the determination result of the flooding situation. The selection unit 350 may transmit the taxiway selection result to the notification unit 352. The notification unit 352 may notify the user of the taxiway via an electric bulletin board, voice guidance, transmission of an emergency early warning mail limited to users in the target area, or a guidance site on the Internet. Details of processing performed by the selection unit 350 will be described later.

  The water stop plate control unit 360 controls the water stop plate 364 for stopping the expansion of the water based on the determination result of the water infiltration state. For example, the water stop plate control unit 360 transmits a control signal to the water stop plate actuator 362. The water stop plate 364 is operated by driving the water stop plate actuator 362 that has received the control signal.

  In the inundation detection system 10, the acquisition unit 320, the air conditioning control unit 330, the storage unit 340, the selection unit 350, and the water stop plate control unit 360 may be omitted. Moreover, the inundation detection system 10 of this example is not restricted to what performs air-conditioning control. The physical quantity detection result may be used for control other than air conditioning control. Further, the inundation detection system 10 of this example is not limited to the one that selects the guide path by the selection unit 350 or controls the water stop plate 364 by the water stop plate control unit 360. The inundation status may be judged and notified to a terminal device or command device carried by a specific person such as a security company or an administrator.

  FIG. 2 is a diagram illustrating an example of a configuration of the wireless device 100 according to the first embodiment. The wireless device 100 of this example includes a sensor unit 110, an antenna unit 122, a transmission / reception control unit 124, a storage unit 126, a power supply unit 128, and an electrode unit 129. The sensor unit 110 is a physical quantity sensor such as a pressure sensor 112, a temperature sensor and humidity sensor 114, and an illuminance sensor 116. However, the wireless device 100 does not have to include all of the pressure sensor 112, the temperature and humidity sensor 114, and the illuminance sensor 116. Further, the wireless device 100 may not include the sensor unit 110.

  The antenna unit 122 transmits a signal from the wireless device 100 and receives a signal from the repeater 200. For example, the wireless device 100 and the repeater 200 communicate using radio waves in a frequency band of 920 MHz. However, the wireless device 100 and the repeater 200 may communicate using radio waves in other frequency bands.

  The transmission / reception control unit 124 generates and supplies a signal to be transmitted from the antenna unit 122, or processes the received signal. The transmission / reception control unit 124 may control the communication frequency of the wireless device 100. The storage unit 126 stores identification information (ID) for identifying the wireless device 100 in advance. The storage unit 126 may temporarily store the physical quantity detection result by the sensor unit 110. The transmission / reception control unit 124 may read the identification information and the physical quantity detection result from the storage unit 126 and generate a signal including the identification information and the physical quantity detection result.

  The power supply unit 128 is a power source of the wireless device 100, for example, a battery. The electrode part 129 has a plurality of electrodes. As the wireless device 100 is submerged, a plurality of electrodes may be short-circuited with water, whereby transmission / reception of signals from the wireless device 100 antenna unit 122 may be stopped. The electrode unit 129 may be an electrode part in a circuit constituting the sensor unit 110, the antenna unit 122, the transmission / reception control unit 124, the storage unit 126, and the power supply unit 128. In this case, a separate electrode unit 129 is used. There is no need to provide. For example, the wireless device 100 loses its function as a sensor due to submersion and cannot periodically transmit a signal via the repeater 200.

  FIG. 3 is a diagram illustrating an example of the configuration of the repeater 200. The repeater 200 includes an antenna unit 204, a transmission / reception control unit 206, a storage unit 208, and a power supply unit 210. The antenna unit 204 transmits signals from the repeater 200 and receives signals from the radio apparatus 100 and other repeaters 200. The transmission / reception control unit 206 generates and supplies a signal to be transmitted from the antenna unit 204, or processes the received signal. The signal supplied from the transmission / reception control unit 206 to the antenna unit 204 may include the identification information received from the wireless device 100 and the physical quantity detection result. In addition, the transmission / reception control unit 206 executes processing for the repeaters 200 and the parent device 250 to perform multi-hop wireless mesh network communication.

  The storage unit 208 may temporarily store identification information and physical quantity detection results received from the wireless device 100. The power supply unit 210 is a power source of the repeater 200 and may be a battery or a power circuit that converts power from an external power source into desired power and supplies the power.

  FIG. 4 is a diagram showing an example of the configuration of base unit 250. Base unit 250 includes antenna unit 254, transmission / reception control unit 256, storage unit 258, power supply unit 260, and interface 262. The base unit 250 may have the same configuration as the repeater 200 except that the base unit 250 has an interface 262 for connecting to the communication network line 6.

  FIG. 5 is a flowchart showing the processing of the inundation detection system 10 in the first embodiment. The wireless device 100 of the present example detects a physical quantity at the installation point by the sensor unit 110 in a state where it is not flooded (step S100: NO) (step S101). The wireless device 100 transmits a signal including a physical quantity detection result and identification information through the antenna unit 122 in a state where the wireless device 100 is not submerged (step S102). The wireless device 100 may transmit a signal including a physical quantity detection result and identification information to the repeater 200 or the parent device 250. The process of step S101 corresponds to a stage of performing wireless communication between the wireless device 100 and the repeater 200 (or the parent device 250).

  The identification information is used to identify the wireless device 100 that has detected the physical quantity. On the other hand, when the wireless device 100 is flooded (step S100: YES), the wireless device 100 stops transmitting a signal including the physical quantity detection result and the identification information (step S103). In the inundation detection system 10 of this example, the wireless device 100 may stop transmitting signals as the inundation occurs. Therefore, it is not necessary to provide a special water immersion sensor in the wireless device 100 itself, so that the structure can be simplified.

  When the repeater 200 receives a signal including the physical quantity detection result and the identification information from the wireless device 100 (step S104), the repeater 200 transfers the received signal to the parent device 250 (step S105). The signal may be transferred via a multi-hop wireless mesh network constituted by a plurality of repeaters 200 and a parent device 250.

  The server computer 300 receives the physical quantity detection result and the identification information from the parent device 250 via the communication network line 6 (step S106). When the server computer 300 receives the physical quantity detection result (step S106: YES), the air conditioning control unit 330 sets the wireless device 100 based on the physical quantity detection result such as temperature, humidity, illuminance, or pressure. Air conditioning for the provided point is controlled (step S107).

  For example, the server computer 300 reads from the storage unit 340 a table that associates the identification information of each of the wireless devices 100a to 100e with the installation position information. The server computer 300 may refer to the received physical quantity detection result, identification information, and the read table. Thereby, the physical quantity for every installation position of the radio | wireless apparatus 100a-the radio | wireless apparatus 100e may be acquired, and air conditioning may be controlled for every installation position.

  If the server computer 300 does not receive the physical quantity detection result and the identification information from the specific wireless device 100 (step S106: NO) and the predetermined period has elapsed (step S108: YES), the inundation determination unit 310 Then, it is determined that the specific wireless device 100 has been submerged (step S109). The inundation determining unit 310 may determine that each point where the wireless device 100a to the wireless device 100e is installed is inundated by detecting the stop of transmission of signals from the wireless devices 100a to 100e.

  The processing of step S106, step S108, and step S109 is a stage in which the flooding state is determined based on whether or not the radio wave intensity of the signal received by the repeater 200 (or base unit 250) is zero, that is, by the repeater 200. This corresponds to the stage of judging the flooding status based on the presence or absence of the received signal. Therefore, the processing of step S106, step S108, and step S109 is performed based on the radio field intensity of the signal received by one device of the wireless device 100 and the repeater 200 (or the parent device 250) from the other device. This corresponds to an example of a stage for judging the inundation situation at the point where is installed.

  In addition, when the transmission of a signal is confirmed from the wireless device 100d installed at the height H1, the transmission of a signal is confirmed from the wireless device 100e installed at the height H2 (H2> H1). In this case, the inundation determination unit 310 can determine that the water has been submerged from the reference surface 2 to the height H1, but has not been submerged up to the height H2. Thereby, even when using the wireless device 100 that stops transmission of signals as it is submerged, it is possible to determine not only the presence of submersion but also the water level.

  The selection unit 350 may select a guide path to a region with less flooding based on the determination result of the flooding status at each point where the plurality of wireless devices 100a to 100e are installed (step S110). Thereby, a guidance path can be alert | reported quickly. Moreover, the water stop board control part 360 stops the water stop board 364 for stopping the expansion of inundation as needed based on the judgment result of the inundation situation of each location where the radio | wireless apparatuses 100a-100e are arrange | positioned. May be controlled (step S111). Based on the determination result of the flooding condition, the water stop plate 364 for stopping the flooding is controlled, so that the flooding can be prevented from spreading.

  FIG. 6 is a flowchart illustrating an example of the guidance route selection process. FIG. 6 shows the contents of the guideway selection process in step S110 of FIG. First, the inundation determination unit 310 determines the inundation status at each point where the wireless devices 100a to 100e are installed. In particular, the inundation determination unit 310 calculates the inundation start time of the wireless devices 100a to 100e based on the time when the transmission stop of the signal from the wireless devices 100a to 100e is detected (step S120).

  The selection unit 350 may select the guide path based on the inundation start timing of each of the wireless devices 100a to 100e. The earlier the inundation starts, the higher the water level at a certain point. Therefore, even when using the wireless device 100 that stops transmission of signals as it is submerged, it is possible to select an appropriate guiding path in anticipation of the degree of submergence.

  The selection unit 350 of this example reads map data from the storage unit 340 (step S121). The selection unit 350 may acquire identification information of each of the wireless devices 100a to 100e. The selection unit 350 refers to a table that associates the identification information with the installation position information, thereby calculating a direction from the early inundation start point to the late point on the map data (step S122). The selection unit 350 may search for a taxiway based on the calculated direction. In the storage unit 340, the position of the electronic bulletin board indicating the guidance route may be registered. The selection unit 350 may search for a taxiway for each position of the electronic bulletin board.

  As described above, according to the inundation detection system 10 of this example, no wiring is required when the wireless device 100 is installed. In addition, since a plurality of communication devices such as the repeater 200 constitute a multi-hop wireless mesh network, even if the communication state is not good, such as underground or in a structure, the parent device is connected via the multi-hop wireless mesh network. The signal can be transmitted to the machine 250.

  The inundation detection system 10 of this example can be used as another control system such as an air-conditioning control system in normal times when it is not inundated. Or, conversely, an air conditioning control system or the like can be used as the inundation detection system 10 during inundation. Since the wireless device 100 only needs to transmit a signal, a plurality of types of wireless devices 100 can be used for the inundation detection system 10. Therefore, a plurality of types of control systems using a plurality of types of sensors can be integrated and used as the inundation detection system 10. As described above, according to the present embodiment, the inundation detection system 10 having versatility can be realized.

  FIG. 7 is a flowchart showing the processing of the inundation detection system 10 in the second embodiment. In the inundation detection system 10 according to the second embodiment, the wireless device 100 does not include the sensor unit 110. Accordingly, the physical quantity detection result is not transmitted from the wireless device 100 to the repeater 200 and the parent device 250, and identification information is transmitted (step S201). Since the server computer 300 does not acquire the physical quantity detection result, the air conditioning control (step S107 in FIG. 5) by the air conditioning control unit 330 is not executed. Except for these points, the configuration of the inundation detection system 10 of the second embodiment is the same as the inundation detection system 10 of the first embodiment shown in FIGS. 1 to 6. Therefore, repeated description is omitted.

  According to the inundation detection system 10 of this example, the wireless device 100 only needs to be able to wirelessly transmit a signal including identification information, and does not need to have the sensor unit 110. Therefore, the inundation detection system 10 is configured with a simple configuration. can do.

  FIG. 8 is a diagram illustrating an outline of the inundation detection system 10 according to the third embodiment. The inundation detection system 10 of this example includes a plurality of wireless devices 150a, 150b, 150c, 150d, and 150e housed in a waterproof casing 152 as the wireless device 150. In the following description, the wireless devices 150a to 150e may be collectively referred to as the wireless device 150. The repeater 200 of this example may include a radio wave intensity determination unit 202. Similarly, for the case where base unit 250 directly receives a signal from wireless device 150, base unit 250 may also include radio wave intensity determination unit 252.

  The radio field intensity determination unit 202 and the radio field intensity determination unit 252 of this example measure the radio field intensity of a signal received from the wireless device 150. The radio field strength determination unit 202 may determine the radio field strength using an RSSI (Received Signal Strength Indicator) circuit, or may determine the radio field strength using PER (packet error rate).

  Due to the difference in dielectric constant between air and water, radio waves are more easily attenuated in water than in air. Therefore, the higher the water level around the wireless device 150, the greater the attenuation of the signal radio waves. In FIG. 8, for example, when the case where the wireless device 150c transmits a signal and the repeater 200b receives a signal is provided in the repeater 200b from the water level D1 to the water level D2 (D2> D1). The radio wave intensity of the signal measured by the radio wave intensity judgment unit 202 becomes weak.

  The repeater 200 adds the information of the radio field intensity measurement result to the received signal and transfers the signal to the base unit 250. Therefore, the identification information and the radio wave intensity are associated with each other and transferred to base unit 250. In the server computer 300 of this example, the inundation determination unit 310 acquires the measurement result of the radio field intensity by the radio field intensity determination unit 202 from the parent device 250 and determines the inundation status based on the measurement result of the radio field intensity. The inundation determination unit 310 determines that the water level around the wireless device 150 is higher as the radio wave intensity is weaker.

  FIG. 9 is a diagram illustrating an example of the configuration of the wireless device 150 according to the third embodiment. The wireless device 150 is accommodated in the housing 152. The casing 152 has a waterproof structure that does not have the opening 104 through which water passes. Therefore, since the wireless device 150 does not flow into the interior, transmission does not stop even if it is submerged. The wireless device 150 of this example includes a sensor unit 110, an antenna unit 122, a transmission / reception control unit 124, a storage unit 126, and a power supply unit 128. These configurations are the same as those of the wireless device 150 shown in FIG. The configuration is the same.

  FIG. 10 is a flowchart showing the processing of the inundation detection system 10 in the third embodiment. The wireless device 150 of this example detects a physical quantity by the sensor unit 110 (step S300). The wireless device 150 transmits a signal including the physical quantity detection result and the identification information through the antenna unit 122 (step S301). The wireless device 150 may transmit a signal including a physical quantity detection result and identification information to the repeater 200 or the parent device 250. The process of step S301 corresponds to a stage of performing wireless communication between the wireless device 150 and the repeater 200 (or the parent device 250).

  Waiting for the repeater 200 to receive a signal including the physical quantity detection result and the identification information from the wireless device 150 (step S302: YES), the radio wave intensity determining unit 202 determines the radio wave intensity of the signal received from the wireless device 150. Is measured (step S303). The transmission / reception control unit 206 provided in the repeater 200 adds information on the radio field intensity measurement result to the signal including the received physical quantity detection result and identification information, and generates a new signal. Repeater identification information for identifying the repeater 200 received from the radio apparatus 150 may be further added to the new signal.

  The repeater 200 transfers a signal including a physical quantity detection result, a radio wave intensity measurement result, and identification information (step S304). The signal may be transferred to the parent device 250 via a multi-hop wireless mesh network configured by a plurality of repeaters 200 and the parent device 250.

  The server computer 300 receives the physical quantity detection result, the radio field intensity measurement value, and the identification information from the parent device 250 via the communication network line 6 (step S305). When the server computer 300 receives the physical quantity detection result and the radio field intensity measurement value (step S305: YES), the inundation determination unit 310 determines the water level based on the radio field intensity (step S306). The process of step S306 corresponds to an example of a stage in which one of the wireless device 150 and the communication device determines the inundation status at the point where the wireless device 150 is installed based on the radio wave intensity of the signal received from the other device. To do.

  The storage unit 340 may store in advance a table or conversion formula indicating the relationship between the radio wave intensity and the water level. The inundation determining unit 310 refers to a table or the like, and there is a signal indicating that the water level is not zero in any of the signals based on the radio wave intensity of the signal from each of the wireless devices 150a to 150e. Determine whether or not.

  As a result of the determination of the water level based on the radio wave intensity, when it is determined that there is no abnormality and the water level is zero (step S307: YES), the air conditioning control unit 330 detects a physical quantity such as temperature, humidity, illuminance, or pressure. Based on the result, the air conditioning at the point where the wireless device 150 is provided is controlled (step S308). On the other hand, when it is determined that the water level is not zero (step S307: NO), it is considered that the inundation has occurred.

  When inundation occurs (step S307: NO), the selection unit 350 moves to a region with less inundation based on the determination result of the inundation situation at each point where the plurality of wireless devices 150a to 150e are installed. May be selected (step S309). Further, if necessary, the water stop plate control unit 360 may be provided with a water stop plate 364 for stopping the inundation based on the determination result of the water level at each point where the wireless devices 150a to 150e are arranged. You may control (step S310).

  FIG. 11 is a flowchart illustrating an example of the guidance route selection process. FIG. 11 illustrates an example of the guidance route selection process in step S309 of FIG. The inundation determination unit 310 calculates the water level at each point where the wireless devices 150a to 150e are installed (step S320). The inundation determination unit 310 may calculate the water level for each piece of identification information based on a table or a conversion formula indicating the relationship between the radio wave intensity and the water level.

  The selection unit 350 of this example reads map data from the storage unit 340 (step S321). Further, the selection unit 350 may read a table that associates the identification information with the installation position information from the storage unit 340. The selection unit 350 uses the calculation result of the water level for each identification information in step S320, the table for associating the identification information with the installation position information, and the map data, on the map data, from the higher water level to the lower water level. The direction toward is calculated (step S322). The selection unit 350 may search for a taxiway based on the calculated direction.

  FIG. 12 is a flowchart illustrating another example of the guidance path selection process. FIG. 12 illustrates an example of the guidance route selection process in step S309 of FIG. The inundation determination unit 310 calculates the change speed of the water level at each point based on the time change of the radio wave intensity at each point where the wireless devices 150a to 150e are installed (step S330). Here, the change speed of the water level may mean a time change of the water level per unit time.

  The inundation determination unit 310 may calculate the water level for each piece of identification information at a plurality of times by the same method as in step S320 of FIG. The inundation determination unit 310 may calculate the time change rate of the water level at each point based on the amount of change in the water level between times.

  The selection unit 350 of this example reads map data from the storage unit 340 (step S331). The selection unit 350 uses the calculation result of the water level change rate for each identification information in step S330, the table for associating the identification information with the installation position information, and the map data, and moves away from the point where the water level rises rapidly on the map data. The direction may be calculated (step S332). The selection unit 350 may search for a taxiway based on the calculated direction.

  As described above, according to the inundation detection system 10 of the present example, the wireless device 150 is housed in the waterproof casing 152, and the casing 152 does not have the opening 104, so that water does not flow inside. Therefore, it is difficult to be affected by the installation environment. The inundation determination unit 310 can determine not only the presence of inundation but also the water level. Further, the inundation determination unit 310 can calculate the rate of change of the water level based on the time change of the radio wave intensity. Therefore, not only the presence / absence of water immersion, but also the water level and the rate of increase of the water level can be considered.

  In the present embodiment, the case where the calculated water level or the change speed of the water level is used for the guide path selection process has been described, but the present invention is not limited to this case. The water stop plate 364 may be controlled in consideration of the calculated water level or the change speed of the water level. Moreover, you may report to the terminal device which a specific person, such as a security company and an administrator, carries out, without performing taxiway selection based on the calculated change speed or level of the water level.

  FIG. 13 is a flowchart showing the processing of the inundation detection system 10 in the fourth embodiment. This example includes a pressure sensor 112 as the sensor unit 110 in the inundation detection system 10 according to the third embodiment, and the inundation determination unit 310 uses the detection result of the radio wave intensity and the detection result of the pressure sensor 112 in combination. To determine the inundation status. Except for this point, the configuration of this example is the same as that of the third embodiment, and thus detailed description thereof is omitted.

  The pressure sensor 112 detects the pressure (step S350). The pressure sensor 112 may be a sensor that can be used as both an atmospheric pressure sensor and a water pressure sensor. In this case, the pressure sensor 112 may detect the air pressure at the installation point when the wireless device 150 is not submerged, and may detect the water pressure at the installation point when the wireless device 150 is submerged.

  The wireless device 150 transmits a signal including the pressure detection result and the identification information (step S351). Therefore, when the wireless device 150 is not submerged, a signal including the atmospheric pressure detection result and the identification information may be transferred. On the other hand, when the wireless device 150 is flooded, a signal including the detection result of the water pressure and the identification information may be transferred. The processing from step S350 to step S356 is the same as the processing from step S300 to S305 in FIG. 10 except that the physical quantity detection result includes the pressure detection result.

  The server computer 300 receives the pressure detection result, the radio field intensity measurement value, and the identification information from the parent device 250 via the communication network line 6 (step S355). When the server computer 300 receives the pressure detection result, the measured value of the radio wave intensity, and the identification information (step S355: YES), the inundation determination unit 310 determines the change in the radio wave intensity and the detection result of the pressure sensor 112. Are used together to determine the water level (step S356).

  The pressure value detected by the pressure sensor 112 when the wireless device 150 is submerged is higher than that when the wireless device 150 is not submerged. Therefore, the inundation determination unit 310 can determine whether or not the wireless device 150 has submerged based on the increase in the pressure value detected by the pressure sensor 112. On the other hand, according to the change in radio field intensity, the water level around the wireless device 150 can be determined. Therefore, in the present embodiment, the presence or absence of flooding is determined based on the detection result of the pressure sensor 112, and when it is determined that the pressure sensor 112 has flooded, the water level is determined based on the change in radio wave intensity. May be.

  However, the present embodiment is not limited to this case, and any embodiment may be used as long as it determines the inundation situation by using the change in radio wave intensity and the detection result of the pressure sensor 112 in combination. When the inundation is detected based on at least one of the change in the radio wave intensity and the detection result of the pressure sensor 112, the inundation determination unit 310 may determine that it has finally been submerged. Alternatively, when both the determination based on the change in the radio wave intensity and the determination based on the detection result of the pressure sensor 112 indicate inundation, the inundation determination unit 310 may determine that the submergence is finally inundated.

  The processing from step S356 to step S360 is the same as the processing from step S306 to step S310. The detection result of the atmospheric pressure detected by the pressure sensor 112 when the wireless device 150 is not submerged may be used for air conditioning control or climate observation when the water level is zero (step S357: YES). According to the inundation detection system 10 of the present embodiment, since the inundation situation is determined using both the change in radio wave intensity and the detection result of the pressure sensor 112, the detection accuracy of the inundation situation can be improved.

  FIG. 14 is a flowchart showing the processing of the inundation detection system 10 in the fifth embodiment. In the inundation detection system 10 according to the fifth embodiment, the wireless device 150 does not include the sensor unit 110.

  Accordingly, the physical quantity detection result is not transmitted from the wireless device 150 to the repeater 200 and the parent device 250, but identification information is transmitted (step S400). Since the server computer 300 does not acquire the physical quantity detection result, the air conditioning control (step S308 in FIG. 10) by the air conditioning control unit 330 is not executed. Except for these points, the configuration of the flood detection system 10 of the fifth embodiment is the same as the flood detection system 10 of the third embodiment shown in FIGS. 8 to 10. Therefore, repeated description is omitted.

  According to the inundation detection system 10 of this example, the wireless device 150 only needs to be able to wirelessly transmit a signal including identification information. Therefore, since the wireless device 150 does not need to include the sensor unit 110, the inundation detection system 10 can be configured with a simple configuration.

  FIG. 15 is a flowchart showing processing of the inundation detection system 10 in the sixth embodiment. In the third to fifth embodiments, the radio wave intensity determining unit 202 is provided in the repeater 200 and the parent device 250, and the radio wave intensity determining unit 202 measures the radio wave intensity of the signal received from the wireless device 150. Explained the case. On the other hand, in this example, the radio wave intensity determining unit 202 is provided on the wireless device 150 side, and the radio wave intensity determining unit 202 measures the radio wave intensity of the signal received from the repeater 200.

  Therefore, the wireless device 150 of this example is the same as the configuration of FIG. 9 except that the radio wave intensity determination unit 202 is added to the configuration of the wireless device 150 shown in FIG. Note that the sensor unit 110 may be omitted. On the other hand, the repeater 200 of this example does not need to have the radio wave intensity determination unit 202 and may have the same configuration as that shown in FIG. Other configurations may be the same as the inundation detection system 10 in the third to fifth actual forms. Therefore, repeated description is omitted.

  The repeater 200 transmits a request signal to the wireless device 150 (step S501). Waiting for radio apparatus 150 to receive a request signal from repeater 200 (step S502: YES), radio field strength determination unit 202 provided in radio apparatus 150 determines the radio field intensity of the request signal received from repeater 200. Measurement is performed (step S503).

  The transmission / reception control unit 124 in the wireless device 150 generates a signal including the identification information and the reception intensity measurement result. Radio apparatus 150 transmits a signal including the identification information and the measurement result of the received intensity to repeater 200 through antenna unit 122. The repeater 200 may transfer a signal including the identification information and the reception intensity measurement result to the parent device 250. The processing from step S506 to step S510 is the same as the processing of the fifth embodiment shown in FIG. 14 (step S404 to step S408).

  The configuration having the radio wave intensity determination unit 202 on the wireless device 150 side can also be applied to a configuration in which the wireless device 150 transmits a physical quantity detection result as in the third embodiment illustrated in FIG. 10. In this case, the transmission / reception control unit 124 in the wireless device 150 transmits a signal including the identification information, the reception intensity measurement result, and the physical quantity detection result to the repeater 200, and the repeater 200 transfers the signal to the parent device 250.

  Also according to the present embodiment, the inundation determination unit 310 has the wireless device 150 installed based on the radio field intensity of the signal received by one of the wireless device 150 and the repeater 200 (or the master device 250) from the other device. It is possible to judge the inundation situation at the spot. The process of step S507 is based on the radio wave intensity of the signal received by one device of the wireless device 150 and the repeater 200 (or the parent device 250) from the other device, and determines the inundation status at the point where the wireless device 150 is installed. This corresponds to an example of a determination stage.

  FIG. 16 is a diagram illustrating an overview of the inundation detection system 10 according to the seventh embodiment. In the server computer 300, the acquisition unit 320 acquires related information related to flooding. The acquisition unit 320 may acquire related information by communicating with the external server 370 via the communication network line 6. The external server 370 may be a public Web site operated by a national or local government, such as an “X-band MP radar meteorological observation network” (XRAIN) operated by the Japanese Ministry of Land, Infrastructure, Transport and Tourism. The related information may be rainfall information, weather information, water level information, inundation information, earthquake information, or tsunami information. The related information may be warning information that should enhance the monitoring of inundation by the inundation detection system 10 in particular.

  The inundation detection system 10 of this example includes a plurality of wireless devices 170a, 170b, 170c, 170d, and 170e. In the following description, the wireless devices 170a to 170e may be collectively referred to as the wireless device 170. The wireless device 170 has a switching unit 130. Switching unit 130 switches the operation mode of the plurality of wireless devices based on the related information. Except for the above points, the inundation detection system 10 of this example has the same configuration as the first to sixth embodiments. Therefore, repeated description is omitted.

  FIG. 17 is a diagram illustrating an example of a configuration of the wireless device 170 according to the seventh embodiment. The wireless device 170 further includes a switching unit 130 in addition to the configuration of the wireless device 150 of the third embodiment shown in FIG. The transmission / reception control unit 124 may change the transmission / reception control content in response to an instruction to switch the operation mode by the switching unit 130. The sensor unit 110 can be omitted. Further, the wireless device 170 may have a configuration in which a switching unit 130 is added to the configuration of the wireless device 100 of the first embodiment shown in FIG.

  FIG. 18 is a flowchart illustrating a process when inundation-related information is acquired in the inundation detection system 10 according to the seventh embodiment. The flood detection process in the flood detection system 10 of this example is the same as the process in the first to sixth embodiments. Server computer 300 communicates with external server 370 through acquisition unit 320. When acquisition unit 320 acquires related information from external server 370 (step S601: YES), server computer 300 transmits an operation mode switching command to base unit 250 (step S602).

  When repeater 200 receives the operation mode switching command via base unit 250 (step S603: YES), repeater 200 transmits the switching command to wireless devices 170a to 170e (step S604). For example, a switching command is broadcast to all of the wireless devices 170a to 170e via a multi-hop wireless mesh network configured by the parent device 250 and the repeater 200.

  When wireless device 170 receives the operation mode switching command (step S605: YES), switching unit 130 provided in wireless device 170 performs an operation mode switching process (step S606). Therefore, according to the inundation detection system 10 of the present example, when the related information is acquired and the possibility of inundation increases, the operation mode of the plurality of wireless devices 170 can be switched to enhance the inundation monitoring.

  FIG. 19 is a flowchart illustrating an example of the operation mode switching process. FIG. 19 illustrates an example of the operation mode switching process in step S606 of FIG. Switching unit 130 switches the operation mode to a mode in which a plurality of wireless devices 170 can perform multi-hop wireless mesh communication with each other (step S610). When the operation mode is switched to a mode capable of multi-hop wireless mesh communication, the transmission / reception control unit 124 executes transmission / reception control for communication in which the wireless devices 170a to 170e communicate with each other in a multi-hop wireless mesh network. Preferably, the transmission / reception control unit 124 enables the plurality of wireless devices 170a to 170e, the plurality of repeaters 200a to 200c, and the parent device 250 to perform multihop wireless mesh network communication with each other.

  In the mode capable of multihop wireless mesh network communication, it is easier to secure a communication path earlier than in the normal mode not capable of multihop wireless mesh network communication, but the power consumption is larger than in the normal mode. Therefore, during normal times when related information is not acquired by the acquisition unit 320, power consumption is suppressed and the life of the power supply unit 128 (battery) is extended. On the other hand, when related information is acquired by the acquisition unit 320, the operation mode is switched to a mode in which the wireless devices 170 can communicate with each other in the multi-hop wireless mesh network, and the monitoring system can be strengthened.

  FIG. 20 is a flowchart illustrating another example of the operation mode switching process. FIG. 20 illustrates an example of the operation mode switching process in step S606 of FIG. Compared to the case where the acquisition unit 320 has not acquired the related information, the operation mode is switched to a mode in which each wireless device 170 communicates with the repeater 200 (or the parent device 250) at a higher frequency than normal (step S610). . When the operation mode is switched to a mode in which the communication frequency is higher than normal, the transmission / reception control unit 124 controls the communication frequency to be higher than normal. In this example, power consumption can be reduced by reducing the communication frequency during normal times when related information is not acquired by the acquisition unit 320.

  The wireless device 170 sets the communication interval to 10 minutes or more and 24 hours or less, for example, in normal times. That is, the wireless device 170 communicates with the repeater 200 at a relatively low communication frequency such as once an hour or once a day. While not communicating, the sleep mode may be switched to reduce the power consumption of the sensor unit 110, the antenna unit 122, the transmission / reception control unit 124, the storage unit 126, the switching unit 130, and the power supply unit 128.

  According to the processing of this example, power consumption is suppressed and the life of the power supply unit 128 (battery) is extended. Further, even during normal times, communication is not performed at all, and it is possible to know that the wireless device 170 has not failed by performing communication at a predetermined communication interval. Therefore, the number of maintenance steps can be reduced.

  On the other hand, when related information is acquired by the acquisition unit 320, the wireless device 170 sets the communication interval to 30 seconds or more and 5 minutes or less, for example. Thereby, on the other hand, when related information is acquired by the acquisition part 320, the communication frequency can be made higher than usual and the monitoring system can be strengthened.

  The operation mode switching process is not limited to the above case. For example, the processes shown in FIGS. 19 and 20 can be used in combination. When related information is acquired by the acquisition unit 320, the operation mode may be switched so as to enable multi-hop wireless mesh network communication between the plurality of wireless devices 170 and increase the communication frequency.

  As described above, according to the inundation detection system 10 of this example, the life of the power supply unit 128 (battery) can be extended. Therefore, maintenance costs such as battery replacement can be reduced. On the other hand, when related information is acquired by the acquisition unit 320, priority can be given to strengthening the monitoring system over power consumption. Therefore, it is possible to detect a change in the flooding condition in detail.

  In the first to seventh embodiments described above, the inundation determination unit 310, the acquisition unit 320, the air conditioning control unit 330, and the storage unit are added to the server computer 300 that is a device different from the communication device such as the repeater 200 and the parent device 250. Although the case where 340, the selection part 350, and the water stop board control part 360 are provided was shown, this inundation detection system 10 is not restricted to this case. The repeater 200 or the parent device 250 may be provided with a configuration such as the flood determination unit 310. Further, the inundation determination unit 310, the air conditioning control unit 330, the selection unit 350, and the water stop plate control unit 360 may be provided in a plurality of apparatuses.

  Each embodiment in this specification can be combined suitably. As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. It is apparent from the description of the scope of claims that embodiments with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that the output can be realized in any order unless the output of the previous process is used in the subsequent process. Even if the operation flow in the claims, the description, and the drawings is described using “first”, “next”, etc. for convenience, it means that it is essential to carry out in this order. It is not a thing.

2 .. Reference plane 4 .. Ceiling 6 ..Communication network line 10 ..Inundation detection system 100 ..Wireless device 102 ..Housing 104 ..Opening 110 ..Sensor part 112. -Pressure sensor, 114-Temperature sensor and humidity sensor, 116-Illuminance sensor, 122-Antenna unit, 124-Transmission / reception control unit, 126-Storage unit, 128-Power supply unit, 129-Electrode unit , 130, switching unit, 150, wireless device, 152, housing, 170, wireless device, 200, repeater, 202, radio wave intensity judgment unit, 204, antenna unit, 206, transmission / reception control , 208... Storage unit 210.. Power supply unit 250... Master unit 252.. Radio field strength judgment unit 254.. Antenna unit 256.. Transmission / reception control unit 258. ·Power supply 262, Interface, 300, Server computer, 310, Inundation determination unit, 320, Acquisition unit, 330, Air conditioning control unit, 332, Air conditioning equipment server, 340, Storage unit, 350, Selection , 352 .. Notification unit, 360 .. Water stop plate control unit, 362 .. Actuator for water stop plate, 364 .. Water stop plate, 370 .. External server

Claims (16)

A wireless device;
A communication device capable of wireless communication with the wireless device;
An inundation determination unit that determines an inundation situation at a point where the wireless device is installed, based on the radio wave intensity of a signal received by one of the wireless device and the communication device from the other device;
Inundation detection system comprising. As the wireless device is submerged, the wireless device stops transmitting signals,
The inundation determination unit determines that the point where the wireless device is installed has been inundated by detecting the stop of transmission of a signal from the wireless device;
The inundation detection system according to claim 1. The wireless device is housed in a waterproof case,
The inundation determination unit determines that the lower the radio wave intensity is, the higher the water level around the wireless device is.
The inundation detection system according to claim 1. The inundation determination unit calculates a change speed of the water level based on the time change of the radio wave intensity,
The inundation detection system according to claim 3. The wireless device further includes a sensor unit that detects a physical quantity,
In a state where the wireless device is not flooded, the wireless device transmits a physical quantity detection result by the sensor unit.
The inundation detection system according to any one of claims 2 to 4. The inundation detection system includes a plurality of types of wireless devices having different sensors for detecting different physical quantities,
The inundation detection system according to claim 5. The wireless device has a pressure sensor;
The inundation determination unit determines the inundation situation by using the change in the radio wave intensity and the detection result of the pressure sensor in combination.
The inundation detection system according to claim 3. Based on the determination result of the inundation status, further comprising a selection unit for selecting a guide path to an area with less inundation,
The inundation detection system according to any one of claims 1 to 7. The inundation detection system includes a plurality of wireless devices,
The inundation determination unit determines the inundation status at each point where each wireless device is installed,
The selection unit selects the taxiway based on the inundation start time of each wireless device,
The inundation detection system according to claim 8. The plurality of wireless devices include a plurality of wireless devices arranged at different heights.
The inundation detection system according to claim 9. Further comprising a water stop plate control unit for controlling a water stop plate for stopping the expansion of the water based on the determination result of the flooding situation;
The inundation detection system according to any one of claims 1 to 10. The inundation detection system includes a plurality of wireless devices and a plurality of communication devices,
The plurality of communication devices constitute a multi-hop wireless mesh network.
The inundation detection system according to any one of claims 1 to 7. The flood detection system includes a plurality of wireless devices and an acquisition unit that acquires related information related to flooding.
The plurality of wireless devices include a switching unit that switches operation modes of the plurality of wireless devices based on the related information.
The inundation detection system according to any one of claims 1 to 7. The switching unit switches the operation mode to a mode in which the plurality of wireless devices can perform multi-hop wireless mesh communication based on the related information.
The inundation detection system according to claim 13. The switching unit switches the operation mode to a mode in which each wireless device communicates with the communication device based on the related information, compared to a case where the acquisition unit does not acquire the related information.
The inundation detection system according to claim 13. Wirelessly communicating between the wireless device and the communication device;
Determining one of the wireless device and the communication device based on the radio field intensity of the signal received from the other device, the inundation status at the point where the wireless device is installed;
An inundation detection method comprising:

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