JPWO2019159348A1 - Information processing equipment, nodes, wireless communication systems and wireless network control methods - Google Patents

Abstract

The information processing device (5) collects data from a relay node that performs an intermittent operation that periodically repeats an operation section and a sleep section. The information processing device (5) transmits a group ID set in the same node group (NG) to relay nodes (2A to 2C) having communication qualities equal to or higher than a certain value. The information processing device (5) is measured by the measurement node (2D) from the relay node (2A) set as the duty node that is the operation section among the relay nodes (2A to 2C) in the node group (NG). Collect the data.

Description

The present invention relates to information processing devices, nodes, wireless communication systems and wireless network control methods.

In recent years, WSNS (Wireless) in which a plurality of sensor nodes (hereinafter, simply referred to as "nodes"), which are wireless communication devices, are installed as measurement targets, and data acquired by each node is transmitted to an information processing device by wireless communication. Sensor Network System) is known.

For example, each node measures the state of the measurement target and transmits it as data by wireless communication. The information processing device collects the data measured at each node. For example, the information processing device has an aggregator and a gateway (GW), the aggregator transmits the collected data to the GW, and the GW transmits the collected data to the user terminal. For example, the user terminal monitors the state of the measurement target based on the collected data. Examples of measurement targets include cliffs, roads, and buildings. For example, when the measurement target is a cliff, WSNS can be applied to monitor landslides. For example, when the measurement target is a road or a building, monitoring of distortion, cracks, etc. can be mentioned as an application example of WSNS.

In WSNS, each node is installed apart and the radio wave reach of wireless communication is limited. Therefore, a relay node is used as a relay node between the measurement node that measures the state of the measurement target and the information processing device. Multi-hop communication is adopted, in which data is relayed between neighboring nodes. As a result, the information processing apparatus can collect the data measured by the measuring node via the relay node by using the multi-hop communication between the nodes in the WSNS.

Further, in WSNS, each node is equipped with a battery, and each node operates by the electric power of the battery. Therefore, the power available for wireless communication at each node is limited. For example, each node does not have enough electric power to directly communicate with the information processing device. Therefore, each node executes an intermittent operation that starts when necessary. In the intermittent operation, an operation section that operates at a fixed time and a stop section that stops the operation at a fixed time are periodically repeated. For example, the measuring node measures the data in the operating section, and the relay node relays the data measured by the measuring node in the operating section using multi-hop communication.

Here, since the information processing device (aggregator, GW) always operates, the power consumption becomes large. In this case, for example, the power consumption of the information processing apparatus can be reduced by executing the intermittent operation in the same manner as each node (measurement node, relay node).

Japanese Unexamined Patent Publication No. 2010-1148998 JP-A-2015-177283 Japanese Unexamined Patent Publication No. 2008-245102

However, when the information processing device (for example, an aggregator) and the relay node simply use the internal timer to execute an intermittent operation in which the operation section and the stop section are periodically repeated, the internal timer of the information processing device and the relay node is executed. There is a possibility that the time will be different. In this case, as shown in FIG. 28, there is a possibility that the operating section of the information processing device and the operating section of the relay node are also deviated. Specifically, the relay node relays the data measured by the measurement node using multi-hop communication in the operation section, and the information processing device collects the data relayed from the relay node in the operation section. .. Here, if the time of the internal timers of the information processing device and the relay node is different, the timings of the operating section of the information processing device and the operating section of the relay node do not match. As a result, the information processing device has a problem that the data relayed from the relay node cannot be collected in the operation section.

Therefore, as shown in FIG. 29, the relay node stands by in the operation section as a standby state for multi-hop communication. Then, the information processing device (for example, an aggregator) transmits a data transmission command to the relay node at the time of activation (operation section), and the relay node transmits data in response to the data transmission command from the information processing device. As a result, the method shown in FIG. 29 solves the problem shown in FIG. 28, that is, the problem that the information processing apparatus cannot collect the data relayed from the relay node in the operation section. However, in the method shown in FIG. 29, the power consumption of the relay node increases due to the standby state as compared with the case shown in FIG. 28.

Therefore, as shown in FIG. 30, the relay node stands by in the standby state without waiting for reception. At this time, the relay node turns on the transmission / reception unit once every several tens of seconds, transmits a beacon, and waits for reception for several seconds when the beacon is transmitted. The information processing device (for example, an aggregator) constructs a network for the relay node that has transmitted the beacon at the time of activation (operation section), and transmits a data transmission command to the relay node. The relay node transmits data in response to a data transmission command from the information processing device. As a result, in the method shown in FIG. 30, since the transmission / reception unit of the relay node is turned off in the standby state, the power consumption of the relay node can be reduced as compared with the method shown in FIG. However, in the method shown in FIG. 30, since there is a time when the transmission / reception unit of the relay node is turned on in the standby state, the power consumption of the relay node is larger than that in the case shown in FIG. 28.

The technology disclosed in the present application avoids data collection problems while reducing power consumption.

In one embodiment, the information processing apparatus collects data from a node that performs an intermittent operation that periodically repeats an operation section and a sleep section. The information processing device has a group setting unit and an operation control unit. The group setting unit sets the same group for nodes whose mutual communication quality is equal to or higher than a certain value. The operation control unit collects data from the nodes set as the duty nodes that are the operation sections among the nodes in the group.

On one side, it is possible to avoid problems in data collection while reducing power consumption.

FIG. 1 is a schematic view showing an example of the configuration of the wireless communication system according to the first embodiment. FIG. 2 is a block diagram showing an example of a node configuration of the wireless communication system according to the first embodiment. FIG. 3 is an explanatory diagram showing an example of a transition of the remaining battery level of the node of the wireless communication system according to the first embodiment. FIG. 4 is a block diagram showing an example of the configuration of the information processing device of the wireless communication system according to the first embodiment. FIG. 5 is an explanatory diagram showing an example of a network construction process and a group setting process in the wireless communication system according to the first embodiment. FIG. 6 is an explanatory diagram showing an example of buffering upper limit setting processing in the wireless communication system according to the first embodiment. FIG. 7 is an explanatory diagram showing an example of operation processing (data collection) in the wireless communication system according to the first embodiment. FIG. 8 is an explanatory diagram showing an example of operation processing (role change) in the wireless communication system according to the first embodiment. FIG. 9 is a timing chart showing an example of operation processing (data collection and role change) in the wireless communication system according to the first embodiment. FIG. 10 is an explanatory diagram showing the effect of operational processing in the wireless communication system according to the first embodiment. FIG. 11 is a flowchart showing an example of the operation of the wireless communication system according to the first embodiment. FIG. 12 is a flowchart showing an example of group setting processing executed by the information processing apparatus as the operation of the wireless communication system according to the first embodiment. FIG. 13 is a flowchart showing an example of group setting processing executed by the relay node as the operation of the wireless communication system according to the first embodiment. FIG. 14 is a flowchart showing an example of group setting processing executed by the measurement node as the operation of the wireless communication system according to the first embodiment. FIG. 15 is a flowchart showing an example of a buffering upper limit setting process executed by the information processing apparatus as an operation of the wireless communication system according to the first embodiment. FIG. 16 is a flowchart showing an example of the buffering upper limit setting process executed by the relay node as the operation of the wireless communication system according to the first embodiment. FIG. 17 is a flowchart showing an example of an operation process executed by the information processing apparatus as an operation of the wireless communication system according to the first embodiment. FIG. 18 is a flowchart showing an example of an operation process executed by the duty node among the relay nodes as the operation of the wireless communication system according to the first embodiment. FIG. 19 is a flowchart showing an example of an operation process executed by a non-duty node among the relay nodes as the operation of the wireless communication system according to the first embodiment. FIG. 20 is a flowchart showing an example of an operation process executed by the measurement node as the operation of the wireless communication system according to the first embodiment. FIG. 21 is a flowchart showing an example of group setting processing executed by the information processing apparatus as the operation of the wireless communication system according to the second embodiment. FIG. 22 is a flowchart showing an example of a group setting process executed by the duty node among the relay nodes as the operation of the wireless communication system according to the second embodiment. FIG. 23 is a flowchart showing an example of a group setting process executed by a non-duty node among the relay nodes as an operation of the wireless communication system according to the second embodiment. FIG. 24 is a flowchart showing an example of an operation process executed by the duty node among the relay nodes as the operation of the wireless communication system according to the second embodiment. FIG. 25 is a flowchart showing an example of an operation process executed by a non-duty node among the relay nodes as an operation of the wireless communication system according to the second embodiment. FIG. 26 is a diagram showing an example of the hardware configuration of the node. FIG. 27 is a diagram showing an example of the hardware configuration of the information processing device. FIG. 28 is an explanatory diagram showing an example of a problem in the intermittent operation of the information processing device and the relay node. FIG. 29 is an explanatory diagram showing an example of a problem in the intermittent operation of the information processing device and the relay node. FIG. 30 is an explanatory diagram showing an example of a problem in the intermittent operation of the information processing device and the relay node.

Hereinafter, examples of the information processing apparatus, node, wireless communication system, and wireless network control method disclosed in the present application will be described in detail with reference to the drawings. The following examples do not limit the disclosed technology.

[Configuration of wireless communication system]
FIG. 1 is a schematic view showing an example of the configuration of the wireless communication system 1 according to the first embodiment. The wireless communication system 1 shown in FIG. 1 is composed of, for example, a WSNS, and has a plurality of nodes 2 which are wireless communication devices, a gateway (GW) 3, and an aggregator 4. Here, in this embodiment, for example, 31 nodes 2 are installed (hereinafter, may be referred to as nodes 2-1 to 2-31).

For example, each node 2 measures the state of the measurement target and transmits it as data by wireless communication. The aggregator 4 is a communication device that communicates and connects between each node 2 and the GW 3. The aggregator 4 is a device that collects data transmitted from each node 2, for example, an information processing device such as a server. The aggregator 4 transmits the collected data to the GW 3, and the GW 3 transmits the collected data to the user terminal. For example, the user terminal monitors the state of the measurement target based on the collected data. In this embodiment, one device that integrates the function of the GW 3 and the function of the aggregator 4 may be the information processing device 5.

Examples of measurement targets include cliffs, roads, and buildings. For example, when the measurement target is a cliff, WSNS can be applied to monitor landslides. For example, when the measurement target is a road or a building, monitoring of distortion, cracks, etc. can be mentioned as an application example of WSNS.

In WSNS, each node 2 is installed apart from each other, and the radio wave range of wireless communication is limited. Therefore, between the measurement node for measuring the state of the measurement target and the information processing device 5 (aggregator 4, GW3). , A relay node is installed as a relay node, and multi-hop communication is adopted in which data is relayed between neighboring nodes. As a result, the information processing apparatus 5 can collect the data measured by the measurement node via the relay node by using the multi-hop communication between the nodes in the WSNS.

In WSNS, each node 2 is equipped with a battery, and each node 2 operates by the electric power of the battery. Each node 2 executes an intermittent operation that starts when necessary. In the intermittent operation, an operation section that operates at a fixed time and a stop section that stops the operation at a fixed time are periodically repeated. For example, the measuring node measures the data in the operating section, and the relay node relays the data measured by the measuring node in the operating section using multi-hop communication.

Further, in the WSNS, the information processing device 5 (aggregator 4, GW 3) is also equipped with a battery, and the information processing device 5 operates by the electric power of the battery. The information processing device 5 also executes an intermittent operation in the same manner as each node 2. For example, the information processing device 5 transmits a data request to the relay node at the time of activation (operation section), and the relay node transmits data in response to the data request from the information processing device in the operation section.

[Configuration of each node]
FIG. 2 is a block diagram showing an example of the configuration of the node 2 of the wireless communication system 1 according to the first embodiment. The node 2 shown in FIG. 2 has an MCU (Micro Controller Unit) 200, a sensor element 210, an energy harvesting element 220, a battery 230, a power supply control unit 240, a radio unit 250, and a storage unit 260. ..

The sensor element 210 is an element that detects the state of the sensing target (measurement target). The energy harvesting element 220 is, for example, a power generation element such as a vibration power generation element, a photovoltaic power generation element, a temperature power generation element, or a radio wave power generation element. The battery 230 stores, for example, the electric power generated by the energy harvesting element 220. The power supply control unit 240 controls the energy harvesting element 220 and the battery 230. The wireless unit 250 wirelessly communicates with another node 2 existing within a wireless range of, for example, about several tens of centimeters by multi-hop communication. The storage unit 260 has an area for storing various information and programs and an area for temporarily storing (buffering) data. The MCU 200 controls the entire node 2.

Node 2 acquires data by intermittent operation and transmits the acquired data. FIG. 3 is an explanatory diagram showing an example of a transition of the remaining battery level of the node 2 of the wireless communication system 1 according to the first embodiment. In FIG. 3, the horizontal axis represents time, and the vertical axis represents the remaining amount of the battery 230 (remaining amount of battery). For example, from time t0 to time t1, the battery 230 stores (charges) the electric power generated by the energy harvesting element 220. Next, the battery 230 is significantly discharged by the processing of the MCU 200 and the radio unit 250 when the node 2 acquires the data from the time t1 to the time t2, and the node 2 transmits the data from the time t2 to the time t3. Then, after the node 2 transmits the data, the battery 230 charges the electric power generated by the energy harvesting element 220 from time t3 to time t4.

The storage unit 260 has a group ID table 261. The group ID table 261 contains a first area that stores an ID that identifies the local node group, a second area that stores an ID that identifies the parent node group of the local node group, and a node group that is a child of the local node group. It has a third area for storing an ID to be identified. Examples of these IDs include MAC addresses.

The node group and ID (group ID) will be described later.

The storage unit 260 further has an LQI table 262. The LQI table 262 is an area for storing the communication quality of data when the on-duty node of the own node group receives the data transmitted from the node group of the transmission source.

Here, the node group includes one duty node and a non-duty node other than the duty node. The duty node corresponds to the relay node that has shifted to the operation section of the intermittent operation in the node group. The non-duty node corresponds to the relay node that has shifted to the stop section of the intermittent operation in the node group. The relay node, the duty node, and the non-duty node will be described later.

The MCU 200 reads a program stored in the storage unit 260, and configures various processes as functions based on the read program. The MCU 200 has a group setting unit 201, an upper limit setting unit 202, an operation control unit 203, and a control unit 204.

The group setting unit 201 executes the group setting process described later.

The upper limit setting unit 202 executes the buffering upper limit setting process described later.

The operation control unit 203 executes the operation process described later.

The control unit 204 controls the operations of the group setting unit 201, the upper limit setting unit 202, and the operation control unit 203.

[Information processing device configuration]
FIG. 4 is a block diagram showing an example of the configuration of the information processing device 5 of the wireless communication system 1 according to the first embodiment. In this embodiment, one device that integrates the functions of the GW 3 and the functions of the aggregator 4 will be described as the information processing device 5. The information processing device 5 shown in FIG. 4 includes an MCU 500, an energy harvesting element 520, a battery 530, a power supply control unit 540, a communication unit 550, and a storage unit 560.

The energy harvesting element 520 is, for example, a power generation element such as a vibration power generation element, a photovoltaic power generation element, a temperature power generation element, or a radio wave power generation element. The battery 530 stores, for example, the electric power generated by the energy harvesting element 520. The power supply control unit 540 controls the energy harvesting element 520 and the battery 530. The communication unit 550 is an interface for communicating with the node 2 and communicating with the user terminal. The storage unit 560 is an area for storing various information and programs. The MCU 500 controls the entire information processing device 5. The information processing device 5 requests data by intermittent operation and collects the data.

The MCU 500 reads a program stored in the storage unit 560, and configures various processes as functions based on the read program. The MCU 500 has a group setting unit 501, an upper limit setting unit 502, an operation control unit 503, and a control unit 504.

The group setting unit 501 executes the group setting process described later.

The upper limit setting unit 502 executes the buffering upper limit setting process described later.

The operation control unit 503 executes the operation process described later.

The control unit 504 controls the operations of the group setting unit 501, the upper limit setting unit 502, and the operation control unit 503. In addition, the control unit 504 executes the network construction process described later.

[Network construction process]
FIG. 5 is an explanatory diagram showing an example of a network construction process and a group setting process in the wireless communication system 1 according to the first embodiment.

First, the information processing device 5 (aggregator 4, GW3) divides each node 2 into a measurement node and a relay node as a network construction process.

The measurement node is installed on a measurement target (also referred to as a sensing target) such as a cliff, a road, or a building. For example, the measurement node measures the state of the measurement target in the operation section and transmits it as data by wireless communication. For example, of each node 2, nodes 2-1, 2-2, 2-5, 2-9, 2-13, 2-23, 2-26, 2-27, 2-28, 2-31 Set as a measurement node.

The relay node is installed between the measurement node and the GW3. The relay node relays the data measured by the measurement node using multi-hop communication in the operation section and transmits the data to the GW3. For example, of each node 2, nodes 2-3 to 2-4, 2-6 to 2-8, 2-10 to 2-12, 2-14 to 2-16, 2-17 to 2-19, 2-20 to 2-22, 2-24 to 2-25, and 2-29 to 2-30 are set as relay nodes.

[Group setting process]
The information processing device 5 (aggregator 4, GW3) groups the measurement node and the relay node as a group setting process, and sets the duty node in the group of the relay nodes.

For example, in each node 2, nodes 2-1, 2-2, 2-5, 2-9, 2-13, 2-23, 2-26, 2-27, 2-28, 2-31 Are assigned the same group ID as a group of measurement nodes.

Nodes 2-3 to 2-4, 2-6 to 2-8, 2-10 to 2-12, 2-14 to 2-16, 2-17 to 2-19, 2-20 to 2-22, 2 The same group ID is assigned to each of -24 to 2-25 and 2-29 to 2-30 as a group of relay nodes.

Here, it will be specifically described that the relay nodes are grouped and the duty node is set in the group of the relay nodes.

For example, nodes 2-3 to 2-4 are grouped as relay nodes, and nodes 2-3 to 2-4 are assigned the same group ID as node group NG1. In this case, one of the relay nodes 2-3 to 2-4 is set as the on-duty node (relay node 2-4 in FIG. 5), and the other relay nodes are non-duty nodes (relay in FIG. 5). It is set to node 2-3).

For example, nodes 2-6 to 2-8 are grouped as relay nodes, and nodes 2-6 to 2-8 are assigned the same group ID as node group NG2. In this case, one of the relay nodes 2-6 to 2-8 is set as the on-duty node (relay node 2-7 in FIG. 5), and the other relay nodes are non-duty nodes (relay in FIG. 5). It is set to nodes 2-6, 2-8).

For example, nodes 2-10 to 2-12 are grouped as relay nodes, and nodes 2-10 to 2-12 are assigned the same group ID as node group NG3. In this case, one of the relay nodes 2-10 to 2-12 is set as the on-duty node (relay node 2-10 in FIG. 5), and the other relay nodes are non-duty nodes (relay in FIG. 5). It is set to nodes 2-11, 2-12).

For example, nodes 2-14 to 2-16 are grouped as relay nodes, and nodes 2-14 to 2-16 are assigned the same group ID as node group NG4. In this case, one of the relay nodes 2-14 to 2-16 is set as the on-duty node (relay node 2-14 in FIG. 5), and the other relay nodes are non-duty nodes (relay in FIG. 5). It is set to nodes 2-15, 2-16).

For example, nodes 2-17 to 2-19 are grouped as relay nodes, and nodes 2-17 to 2-19 are assigned the same group ID as node group NG5. In this case, one of the relay nodes 2-17 to 2-19 is set as the on-duty node (relay node 2-19 in FIG. 5), and the other relay nodes are non-duty nodes (relay in FIG. 5). It is set to nodes 2-17, 2-18).

For example, nodes 2-20 to 2-22 are grouped as relay nodes, and nodes 2-20 to 2-22 are assigned the same group ID as node group NG6. In this case, one of the relay nodes 2-20 to 2-22 is set as the on-duty node (relay node 2-20 in FIG. 5), and the other relay nodes are non-duty nodes (relay in FIG. 5). It is set to nodes 2-21, 2-22).

For example, nodes 2-24 to 2-25 are grouped as relay nodes, and nodes 2-24 to 2-25 are assigned the same group ID as node group NG7. In this case, one of the relay nodes 2-24 to 2-25 is set as the on-duty node (relay node 2-25 in FIG. 5), and the other relay nodes are non-duty nodes (relay in FIG. 5). It is set to node 2-24).

For example, nodes 2-29 to 2-30 are grouped as relay nodes, and nodes 2-29 to 2-30 are assigned the same group ID as node group NG8. In this case, one of the relay nodes 2-29 to 2-30 is set as the on-duty node (relay node 2-30 in FIG. 5), and the other relay nodes are non-duty nodes (relay in FIG. 5). It is set to node 2-29).

In the group setting process, when the relay nodes are arranged in groups, the communication quality of the relay nodes is used. For example, as the communication quality, LQI (Radio wave communication quality: Link Quality Indicator) can be mentioned, and relay nodes having a mutual communication quality of a certain value or more are arranged in a group. As a result, the information processing device 5 (aggregator 4, GW3) uses the multi-hop communication between the nodes in the WSNS to transmit the data measured by the measurement nodes to the relay nodes arranged in groups in the operation process described later. Buffer and collect. Here, the details of the processing operation of the information processing device 5 and each node in the group setting processing will be described later.

[Buffering upper limit setting process]
FIG. 6 is an explanatory diagram showing an example of a buffering upper limit setting process in the wireless communication system 1 according to the first embodiment. The information processing device 5 (aggregator 4, GW3) controls each group to set the buffering upper limit value so that the number of data to be buffered between the groups is as even as possible as the buffering upper limit setting process. ..

For example, in the buffering upper limit setting process, the information processing apparatus 5 determines the buffering upper limit setting value of each group of relay nodes (node groups NG1 to NG8) and notifies each group to buffer the buffering of each group. Set the upper limit.

For example, the upper limit of buffering can be calculated by the following equation (1).
Nu = ceil (Nm / Ng) (1)

In the equation (1), Nu indicates the upper limit of buffering, Nm indicates the number of measurement nodes, and Ng indicates the number of relay node groups (number of node groups). Further, ceil is a CEIL function (also called a ceiling function), and is an expression that rounds up the value of Nm / Ng to an integer.

In FIG. 6, measurement nodes 2-1 and 2-2, 2-5, 2-9, 2-13, 2-23, 2-26, 2-27, 2-28, and 2-31 are measurement targets. Since it is installed, the number of measurement nodes Nm is "10". Relay nodes 2-3 to 2-4, 2-6 to 2-8, 2-10 to 2-12, 2-14 to 2-16, 2-17 to 2-19, 2-20 to 2-22, 2-24 to 2-25 and 2-29 to 2-30 are grouped into node groups NG1 to NG8, respectively. Therefore, the number of node groups Ng is "8". In this case, the value of Nm / Ng becomes "1.2", and the process of rounding up to "2" is performed by the CEIL function. Therefore, the buffering upper limit value Nu is set to "2".

The duty node of each group of relay nodes (node groups NG1 to NG8) buffers the data measured by the measurement node. Here, each group of relay nodes and the measurement node have a parent-child relationship, and data transmission is performed from the measurement node, which is a child node group, to the duty node in the relay node group, which is a parent node group.

For example, the data measured by the measurement nodes 2-1 and 2-2 is transmitted to the node group NG1 in the operation section (from the measurement nodes 2-1 and 2-2 in FIG. 6 to the relay node 2-4). See the pointing arrow). In the node group NG1, the duty node corresponds to the relay node 2-4 that has shifted to the operation section of the intermittent operation. Here, the number of data buffered by the duty node (relay node 2-4) of the node group NG1 is not the buffering upper limit value. In this case, the data transmitted to the node group NG1 is buffered by the duty node (relay node 2-4) of the node group NG1.

For example, the data measured by the measurement nodes 2-5 and 2-9 is transmitted to the node group NG2 in the operation section (from the measurement nodes 2-5 and 2-9 in FIG. 6 to the relay node 2-7). See the pointing arrow). In the node group NG2, the duty node corresponds to the relay node 2-7 that has shifted to the operation section of the intermittent operation. Here, the number of data buffered by the duty node (relay node 2-7) of the node group NG2 is not the buffering upper limit value. In this case, the data transmitted to the node group NG2 is buffered at the duty node (relay node 2-7) of the node group NG2.

For example, the data measured by the measurement node 2-13 is transmitted to the node group NG4 in the operation section (see the arrow from the measurement node 2-13 to the relay node 2-14 in FIG. 6). In the node group NG4, the duty node corresponds to the relay node 2-14 that has shifted to the operation section of the intermittent operation. Here, the number of data buffered by the duty node (relay node 2-14) of the node group NG4 is not the buffering upper limit value. In this case, the data transmitted to the node group NG4 is buffered at the duty node (relay node 2-14) of the node group NG4.

For example, the data measured by the measurement node 2-23 is transmitted to the node group NG6 in the operation section (see the arrow from the measurement node 2-23 to the relay node 2-20 in FIG. 6). In the node group NG6, the duty node corresponds to the relay node 2-20 that has shifted to the operation section of the intermittent operation. Here, the number of data buffered by the duty node (relay node 2-20) of the node group NG6 is not the buffering upper limit value. In this case, the data transmitted to the node group NG6 is buffered at the duty node (relay node 2-20) of the node group NG6.

For example, the data measured by the measurement node 2-31 is transmitted to the node group NG8 in the operation section (see the arrow from the measurement node 2-31 to the relay node 2-30 in FIG. 6). In the node group NG8, the duty node corresponds to the relay node 2-30 that has shifted to the operation section of the intermittent operation. Here, the number of data buffered by the duty node (relay node 2-30) of the node group NG8 is not the buffering upper limit value. In this case, the data transmitted to the node group NG8 is buffered at the duty node (relay node 2-30) of the node group NG8.

Each group of relay nodes and the measurement node have a parent-child relationship, but if the number of data buffered by the duty node of each group exceeds the buffering upper limit "2", the child node group to the parent node Data is transferred to the group.

For example, the data measured by the measurement nodes 2-26 and 2-27 is transmitted to the node group NG7 in the operation section (from the measurement nodes 2-26 and 2-27 in FIG. 6 to the relay node 2-25). See the pointing arrow). In the node group NG7, the duty node corresponds to the relay node 2-25 that has shifted to the operation section of the intermittent operation. The data transmitted to the node group NG7 is buffered at the duty node (relay node 2-25) of the node group NG7. Here, the number "2" of data buffered by the duty node (relay node 2-25) of the node group NG7 is the buffering upper limit value. Therefore, the duty node (relay node 2-25) of the node group NG7 cannot buffer the data measured by the measurement node 2-28.

In this case, first, the data measured by the measurement node 2-28 is transmitted to the node group NG7 in the operation section (see the arrow from the measurement node 2-28 to the relay node 2-25 in FIG. 6). .. After that, the data transmitted to the node group NG7 is transferred from the duty node (relay node 2-25) of the node group NG7 to the node group NG5 (from the relay node 2-25 in FIG. 6 to the relay node 2-19). See the pointing arrow). In the node group NG5, the duty node corresponds to the relay node 2-19 that has shifted to the operation section of the intermittent operation. The data transferred to the node group NG5 is buffered at the duty node (relay node 2-19) of the node group NG5.

The above-mentioned buffering upper limit setting process is performed between the group setting process and the operation process described later. As a result, the information processing apparatus 5 (aggregator 4, GW3) arranges the data measured by the measurement nodes in groups so that the number of data buffered between the groups is as even as possible in the operation process described later. Collect by buffering at the relay node. Here, the details of the processing operation of the information processing apparatus 5 and each node in the buffering upper limit setting processing will be described later.

[Operation processing (data collection)]
FIG. 7 is an explanatory diagram showing an example of operation processing (data collection) in the wireless communication system 1 according to the first embodiment.

Each group of relay nodes (node groups NG1 to NG8) has a parent-child relationship. Therefore, when the information processing device 5 (aggregator 4, GW3) returns from the sleep state (when the intermittent operation shifts from the stop section to the operation section), the information processing device 5 (aggregator 4, GW3) is directed from the parent node group to the child node group in the operation section. The data request is transmitted using multi-hop communication.

For example, the data request transmitted from the information processing device 5 is transmitted to the node group NG4 in the operation section (see the one-dot chain line arrow from the aggregator 4 to the relay node 2-14 in FIG. 7). Then, the data request transmitted to the node group NG4 is transmitted to the node groups NG3 and NG6 (see the arrow of the alternate long and short dash line from the relay node 2-14 to the relay nodes 2-10 and 2-20 in FIG. 7). ).

Here, the data request transmitted to the node group NG3 is transmitted to the node groups NG1 and NG2 (point-chain arrows from the relay nodes 2-10 in FIG. 7 to the relay nodes 2-4 and 2-7). reference).

On the other hand, the data request transmitted to the node group NG6 is transmitted to the node groups NG5 and NG8 (see the one-dot chain line arrow from the relay node 2-20 to the relay nodes 2-19 and 2-30 in FIG. 7). ). Then, the data request transmitted to the node group NG5 is transmitted to the node group NG7 (see the arrow of the alternate long and short dash line from the relay node 2-19 to the relay node 2-25 in FIG. 7).

As described above, each group of relay nodes (node groups NG1 to NG8) has a parent-child relationship. Therefore, when the on-duty node of each group receives the data request, it transmits the buffered data from the child node group to the parent node group by using multi-hop communication.

For example, the data buffered by the duty node of the node group NG1 is transmitted to the node group NG3 in response to the data request (solid arrow from the relay node 2-4 in FIG. 7 to the relay node 2-10). See). In this case, the data transmitted to the node group NG3 is transmitted to the information processing apparatus 5 via the node group NG4 (from the relay node 2-10 in FIG. 7 to the aggregator 4 via the relay node 2-14). See the solid arrow towards.

For example, the data buffered by the duty node of the node group NG2 is transmitted to the node group NG3 in response to the data request (solid arrow from the relay node 2-7 to the relay node 2-10 in FIG. 7). See). In this case, the data transmitted to the node group NG3 is transmitted to the information processing apparatus 5 via the node group NG4 (from the relay node 2-10 in FIG. 7 to the aggregator 4 via the relay node 2-14). See the solid arrow towards.

For example, the data buffered by the duty node of the node group NG3 is transmitted to the node group NG4 in response to the data request (solid arrow from the relay node 2-10 to the relay node 2-14 in FIG. 7). See). In this case, the data transmitted to the node group NG4 is transmitted to the information processing device 5 (see the solid arrow from the relay node 2-14 to the aggregator 4 in FIG. 7).

For example, the data buffered by the duty node of the node group NG4 is transmitted to the information processing apparatus 5 in response to the data request (see the solid arrow from the relay node 2-14 in FIG. 7 to the aggregator 4). ).

For example, the data buffered by the duty node of the node group NG5 is transmitted to the node group NG6 in response to the data request (solid arrow from the relay node 2-19 to the relay node 2-20 in FIG. 7). See). In this case, the data transmitted to the node group NG6 is transmitted to the information processing apparatus 5 via the node group NG4 (from the relay node 2-20 in FIG. 7 to the aggregator 4 via the relay node 2-14). See the solid arrow towards.

For example, the data buffered by the duty node of the node group NG6 is transmitted to the node group NG4 in response to the data request (solid arrow from the relay node 2-20 to the relay node 2-14 in FIG. 7). See). In this case, the data transmitted to the node group NG4 is transmitted to the information processing device 5 (see the solid arrow from the relay node 2-14 to the aggregator 4 in FIG. 7).

For example, the data buffered by the duty node of the node group NG7 is transmitted to the node group NG5 in response to the data request (solid arrow from the relay node 2-25 to the relay node 2-19 in FIG. 7). See). In this case, the data transmitted to the node group NG5 is transmitted to the information processing apparatus 5 via the node groups NG6 and NG4 (relay nodes 2-19 to 2-20, 2-14 in FIG. 7). See the solid arrow towards Aggregator 4 via.

For example, the data buffered by the duty node of the node group NG8 is transmitted to the node group NG6 in response to the data request (solid arrow from the relay node 2-30 to the relay node 2-20 in FIG. 7). See). In this case, the data transmitted to the node group NG6 is transmitted to the information processing apparatus 5 via the node group NG4 (from the relay node 2-20 in FIG. 7 to the aggregator 4 via the relay node 2-14). See the solid arrow towards.

[Operation processing (role change)]
FIG. 8 is an explanatory diagram showing an example of operation processing (role change) in the wireless communication system 1 according to the first embodiment.

In the operation process, the on-duty node and the non-on-duty node, which are relay nodes, execute intermittent operations having different cycles. In each group of relay nodes (node groups NG1 to NG8), when the remaining battery level (remaining power amount) of the on-duty node is less than or equal to the threshold value, the on-duty node is on-duty node for one non-duty node in the same group. Send a duty signal to set. For example, the duty node receives information on the remaining battery level periodically from two non-duty nodes in the same group, and the remaining battery level of one of the two non-duty nodes is a constant value. In the above case, the duty signal is transmitted to the one non-duty node. Here, when the duty node buffers the data, the duty node passes the data to the one non-duty node (next duty node).

For example, in the node group NG1, the remaining battery level of the relay node 2-4, which is the duty node, is equal to or less than the threshold value. In this case, when the relay node 2-4 receives the information on the remaining battery level from the relay node 2-3 in the node group NG1, if the remaining battery level of the relay node 2-3 is equal to or higher than a certain value, the relay node 2-4 relays. Nodes 2-4 select relay nodes 2-3 and transmit a duty signal to relay nodes 2-3 (see the arrow from relay node 2-4 to relay node 2-3 in FIG. 8). At this time, if the relay node 2-4 is buffering the data, the relay node 2-4 transmits the data to the relay node 2-3. Further, when the relay node 2-4 transmits the duty signal, the relay node 2-4 changes its role (setting) to the non-duty node. The relay node 2-3 changes its role (setting) to the duty node according to the duty signal, and buffers the data transmitted from the relay node 2-4.

For example, in the node group NG2, the remaining battery level of the relay node 2-7, which is the duty node, is equal to or less than the threshold value. In this case, when the relay node 2-7 receives the information on the remaining battery level from the relay nodes 2-6 and 2-8 in the node group NG2, the relay node 2-7 is one of the relay nodes 2-6 and 2-8. When the remaining battery level of 2-8 is equal to or higher than a certain value, the relay node 2-7 selects the relay node 2-8 and transmits the duty signal to the relay node 2-8 (relay node 2 in FIG. 8). See the arrow from -7 to relay node 2-8). At this time, if the relay node 2-7 is buffering the data, the relay node 2-7 transmits the data to the relay node 2-8. Further, when the relay node 2-7 transmits the duty signal, the relay node 2-7 changes its role (setting) to the non-duty node. The relay node 2-8 changes its role (setting) to the duty node according to the duty signal, and buffers the data transmitted from the relay node 2-7.

For example, in the node group NG3, the remaining battery level of the relay node 2-10, which is the duty node, is equal to or less than the threshold value. In this case, when the relay node 2-10 receives the information on the remaining battery level from the relay nodes 2-11 and 2-12 in the node group NG3, the relay node 2-10 is one of the relay nodes 2-11 and 2-12. When the remaining battery level of 2-12 is equal to or higher than a certain value, the relay node 2-10 selects the relay node 2-12 and transmits the duty signal to the relay node 2-12 (relay node 2 in FIG. 8). See the arrow from -10 to relay node 2-12). At this time, if the data is buffered, the relay node 2-10 transmits the data to the relay node 2-12. Further, when the relay node 2-10 transmits the duty signal, the relay node 2-10 changes its role (setting) to the non-duty node. The relay node 2-12 changes its role (setting) to the duty node according to the duty signal, and buffers the data transmitted from the relay node 2-10.

For example, in the node group NG4, the remaining battery level of the relay node 2-14, which is the duty node, is equal to or less than the threshold value. In this case, when the relay node 2-14 receives the information on the remaining battery level from the relay nodes 2-15 and 2-16 in the node group NG4, the relay node 2-14 is one of the relay nodes 2-15 and 2-16. When the remaining battery level of 2-16 is equal to or higher than a certain value, the relay node 2-14 selects the relay node 2-16 and transmits the duty signal to the relay node 2-16 (relay node 2 in FIG. 8). See the arrow from -14 to relay node 2-16). At this time, if the relay node 2-14 is buffering the data, the relay node 2-14 transmits the data to the relay node 2-16. Further, when the relay node 2-14 transmits the duty signal, the relay node 2-14 changes its role (setting) to the non-duty node. The relay node 2-16 changes its role (setting) to the duty node according to the duty signal, and buffers the data transmitted from the relay node 2-14.

For example, in the node group NG5, the remaining battery level of the relay node 2-19, which is the duty node, is equal to or less than the threshold value. In this case, when the relay node 2-19 receives the information on the remaining battery level from the relay nodes 2-17 and 2-18 in the node group NG5, the relay node 2-19 is one of the relay nodes 2-17 and 2-18. When the remaining battery level of 2-18 is equal to or higher than a certain value, the relay node 2-19 selects the relay node 2-18 and transmits the duty signal to the relay node 2-18 (relay node 2 in FIG. 8). See the arrow from -19 to relay node 2-18). At this time, if the relay node 2-19 is buffering the data, the relay node 2-19 transmits the data to the relay node 2-18. Further, when the relay node 2-19 transmits the duty signal, the relay node 2-19 changes its role (setting) to the non-duty node. The relay node 2-18 changes its role (setting) to the duty node according to the duty signal, and buffers the data transmitted from the relay node 2-19.

For example, in the node group NG6, the remaining battery level of the relay node 2-20, which is the duty node, is equal to or less than the threshold value. In this case, when the relay node 2-20 receives the information on the remaining battery level from the relay nodes 2-21 and 2-22 in the node group NG6, the relay node 2-20 is one of the relay nodes 2-21 and 2-22. When the remaining battery level of 2-22 is equal to or higher than a certain value, the relay node 2-20 selects the relay node 2-22 and transmits the duty signal to the relay node 2-22 (relay node 2 in FIG. 8). See the arrow from -20 to relay node 2-22). At this time, if the data is buffered, the relay node 2-20 transmits the data to the relay node 2-22. Further, when the relay node 2-20 transmits the duty signal, the relay node 2-20 changes its role (setting) to the non-duty node. The relay node 2-22 changes its role (setting) to the duty node according to the duty signal, and buffers the data transmitted from the relay node 2-20.

For example, in the node group NG7, the remaining battery level of the relay node 2-25, which is the duty node, is equal to or less than the threshold value. In this case, when the relay node 2-25 receives the information on the remaining battery level from the relay node 2-24 in the node group NG7, if the remaining battery level of the relay node 2-24 is equal to or higher than a certain value, the relay node 2-25 relays. Node 2-25 selects relay node 2-24 and transmits a duty signal to relay node 2-24 (see the arrow from relay node 2-25 to relay node 2-24 in FIG. 8). At this time, the relay node 2-25 transmits the data to the relay node 2-24 when the data is buffered. Further, when the relay node 2-25 transmits the duty signal, the relay node 2-25 changes its role (setting) to the non-duty node. The relay node 2-24 changes its role (setting) to the duty node according to the duty signal, and buffers the data transmitted from the relay node 2-25.

For example, in the node group NG8, the remaining battery level of the relay node 2-30, which is the duty node, is equal to or less than the threshold value. In this case, when the relay node 2-30 receives the information on the remaining battery level from the relay node 2-29 in the node group NG8, if the remaining battery level of the relay node 2-29 is equal to or higher than a certain value, the relay node 2-30 relays. Node 2-30 selects relay node 2-29 and transmits a duty signal to relay node 2-29 (see the arrow from relay node 2-30 to relay node 2-29 in FIG. 8). At this time, the relay node 2-30 transmits the data to the relay node 2-29 when the data is buffered. Further, when the relay node 2-30 transmits the duty signal, the relay node 2-30 changes its role (setting) to the non-duty node. The relay node 2-29 changes its role (setting) to the duty node according to the duty signal, and buffers the data transmitted from the relay node 2-30.

FIG. 9 is a timing chart showing an example of operation processing (data collection and role change) in the wireless communication system 1 according to the first embodiment.

The duty node in the group of relay nodes 2A to 2C (node group NG) relays the data measured by the measurement node 2D, and the information processing apparatus 5 (aggregator 4, GW3) collects the relayed data.

For example, in FIG. 9, the relay nodes 2A to 2C are the relay nodes 2-14 to 2-16 shown in FIGS. 5 to 8, and the measurement node 2D is the measurement node 2-13 shown in FIGS. 5 to 8. Suppose there is. The same group ID is assigned to the relay nodes 2A to 2C as the node group NG.

At time t0, the duty node of the node group NG is the relay node 2A, and the intermittent operation of the relay node 2A shifts from the stop section to the operation section. Further, the intermittent operation of the measurement node 2-D shifts from the stop section to the operation section, and the measurement node 2-D measures the state of the measurement target in the operation section and transmits it as data to the node group NG. In this case, the relay node 2A, which is the duty node of the node group NG, buffers the data transmitted from the measurement nodes 2-D in the operation section.

Here, when the information processing device 5 (aggregator 4) returns from the sleep state, the intermittent operation of the information processing device 5 shifts from the stop section to the operation section. The information processing device 5 transmits a data request to the node group NG in the operation section. The relay node 2A, which is the duty node of the node group NG, transmits the buffered data to the information processing device 5 in response to the data request in the operation section.

Next, at time t1, the remaining battery level (remaining power amount) of the relay node 2A, which is the duty node of the node group NG, is equal to or less than the threshold value. In this case, when the relay node 2A receives the information on the remaining battery level from the relay nodes 2B and 2C in the node group NG, the relay node 2B and 2C among the relay nodes 2B and 2C has a remaining battery level of a certain value or more. 2B is selected, the duty signal is transmitted to the relay node 2B, and its own role (setting) is changed to the non-duty node. The relay node 2B changes its role (setting) to the duty node according to the duty signal.

Here, the information processing device 5 (aggregator 4) goes into a sleep state, and the intermittent operation of the information processing device 5 shifts from the operation section to the stop section. Further, the intermittent operation of the measurement node 2-D shifts from the operation section to the stop section.

Next, at time t2, the remaining battery level of the relay node 2B, which is the duty node of the node group NG, is equal to or less than the threshold value. In this case, when the relay node 2B receives the information on the remaining battery level from the relay nodes 2A and 2C in the node group NG, the relay node 2A and 2C among the relay nodes 2A and 2C has a remaining battery level of a certain value or more. 2C is selected, the duty signal is transmitted to the relay node 2C, and its own role (setting) is changed to the non-duty node. The relay node 2C changes its role (setting) to the duty node according to the duty signal.

Here, the intermittent operation of the measurement node 2-D shifts from the stop section to the operation section, and the measurement node 2-D measures the state of the measurement target in the operation section and transmits it as data to the node group NG. In this case, the relay node 2C, which is the duty node of the node group NG, buffers the data transmitted from the measurement nodes 2-D in the operation section.

Next, at time t3, the remaining battery level of the relay node 2C, which is the duty node of the node group NG, is equal to or less than the threshold value. In this case, when the relay node 2C receives the information on the remaining battery level from the relay nodes 2A and 2B in the node group NG, the relay node 2C among the relay nodes 2A and 2B has a remaining battery level of a certain value or more. 2A is selected, the duty signal and the buffered data are transmitted to the relay node 2A, and its own role (setting) is changed to the non-duty node. The relay node 2A changes its role (setting) to the duty node according to the duty signal, and buffers the data transmitted from the relay node 2C.

Here, the intermittent operation of the measurement node 2-D shifts from the operation section to the stop section.

Further, the same processing as described above is performed at times t3 to t6.

Next, at time t7, the remaining battery level of the relay node 2A, which is the duty node of the node group NG, is equal to or less than the threshold value. In this case, when the relay node 2A receives the information on the remaining battery level from the relay nodes 2B and 2C in the node group NG, the relay node 2B and 2C among the relay nodes 2B and 2C has a remaining battery level of a certain value or more. 2B is selected, the duty signal and the buffered data are transmitted to the relay node 2B, and its own role (setting) is changed to the non-duty node. The relay node 2B changes its role (setting) to the duty node according to the duty signal, and buffers the data transmitted from the relay node 2A.

Here, when the information processing device 5 (aggregator 4) returns from the sleep state, the intermittent operation of the information processing device 5 shifts from the stop section to the operation section. The information processing device 5 transmits a data request to the node group NG in the operation section. The relay node 2A, which is the duty node of the node group NG, transmits the buffered data to the information processing device 5 in response to the data request in the operation section.

Next, at time t8, the remaining battery level of the relay node 2A, which is the duty node of the node group NG, is equal to or less than the threshold value. In this case, when the relay node 2A receives the information on the remaining battery level from the relay nodes 2B and 2C in the node group NG, the relay node 2B and 2C among the relay nodes 2B and 2C has a remaining battery level of a certain value or more. 2B is selected, the duty signal is transmitted to the relay node 2B, and its own role (setting) is changed to the non-duty node. The relay node 2B changes its role (setting) to the duty node according to the duty signal.

Here, the information processing device 5 (aggregator 4) goes into a sleep state, and the intermittent operation of the information processing device 5 shifts from the operation section to the stop section. Further, the intermittent operation of the measurement node 2D shifts from the stop section to the operation section, and the measurement node 2D measures the state of the measurement target in the operation section and transmits it as data to the node group NG. In this case, the relay node 2B, which is the duty node of the node group NG, buffers the data transmitted from the measurement node 2D in the operation section.

FIG. 10 is an explanatory diagram showing the effect of the operation processing in the wireless communication system 1 according to the first embodiment. The horizontal axis represents the period, and the vertical axis represents the power of the information processing device 5 (aggregator 4, GW3). The operating power of the information processing device 5 is 5.3 Wh, and the stopped power is 0 Wh. When the information processing device 5 is not executing the intermittent operation, the power consumption of the information processing device 5 is always 5.3 Wh (see the dotted line in FIG. 10). On the other hand, when the information processing device 5 executes an intermittent operation with the operation time (operation section) of one cycle as 1 minute, the longer the cycle of the stop section, the lower the power consumption of the information processing device 5 (in FIG. 10). See the solid line in).

The information processing device 5 consumes more power than the relay nodes 2A to 2C shown in FIG. Therefore, in the wireless communication system 1 according to the first embodiment, the power consumption can be reduced by setting the stop section longer than the operation section (data collection section) in the information processing device 5. Further, as described above, the relay nodes 2A to 2C change the role of the duty node in the node group NG. Therefore, in the wireless communication system 1 according to the first embodiment, even if the stop section of the information processing device 5 is set to be long, the timing of the operation section (data collection section) of the information processing device 5 is the relay nodes 2A to 2C. It suffices to match the timing of the operation section of any of the duty nodes. Therefore, in the wireless communication system 1 according to the first embodiment, the information processing device 5 can avoid the problem that the data relayed from the relay nodes 2A to 2C cannot be collected in the operation section (data collection section).

[Operation of wireless communication system]
FIG. 11 is a flowchart showing an example of the operation of the wireless communication system 1 according to the first embodiment.

First, the network construction process (step S1) is performed, and the measurement node and the relay node are set from each node 2. Next, the group setting process (step S2), the buffering upper limit setting process (step S3), and the operation process (step S4) are performed.

FIG. 12 is a flowchart showing an example of a group setting process executed by the information processing apparatus 5 as an operation of the wireless communication system 1 according to the first embodiment.

The information processing device 5 transmits an LQI request to the relay node (step S201) and collects LQI information from the relay node (step S202). For example, the LQI information transmitted from the relay node includes the LQI and the position information indicating the installed position. The information processing apparatus 5 groups relay nodes (hereinafter, referred to as relay nodes 2A to 2C) that are close to each other by position information and have LQIs of a certain value or more with each other (step S203).

The information processing device 5 notifies each node 2 of the group ID. The group ID notified to each node 2 includes an ID for identifying the own node group, a parent node group of the local node group, and a child node group of the local node group (step S204). Then, the information processing apparatus 5 transmits a duty signal for setting the duty node to each node group NG of the relay nodes 2A to 2C (step S205).

FIG. 13 is a flowchart showing an example of group setting processing executed by the relay nodes 2A to 2C as the operation of the wireless communication system 1 according to the first embodiment.

The relay nodes 2A to 2C wait for the LQI request transmitted from the information processing device 5 (step S211; No). Here, when the relay nodes 2A to 2C receive the LQI request transmitted from the information processing device 5 (step S211; Yes), the relay nodes 2A to 2C transmit the LQI information to the information processing device 5 (step S212).

The relay nodes 2A to 2C wait for the group ID transmitted from the information processing device 5 (step S213; No). Here, when the relay nodes 2A to 2C receive the group ID transmitted from the information processing apparatus 5 (step S213; Yes), the relay nodes 2A to 2C store the group ID in the group ID table 261 of the storage unit 260 (step S214).

Here, the relay node 2A of the relay nodes 2A to 2C receives the duty signal transmitted from the information processing apparatus 5 (step S215; Yes). In this case, the relay node 2A stores the duty signal in the storage unit 260 and recognizes that its role (setting) is the duty node (step S216).

On the other hand, the relay nodes 2B and 2C among the relay nodes 2A to 2C do not receive the duty signal from the information processing device 5 (step S215; No). In this case, the relay nodes 2B and 2C recognize that their role (setting) is a non-duty node.

FIG. 14 is a flowchart showing an example of the group setting process executed by the measurement node 2D as the operation of the wireless communication system 1 according to the first embodiment.

The measurement node 2D waits for the group ID transmitted from the information processing device 5 (step S221; No). Here, when the measurement node 2D receives the group ID transmitted from the information processing device 5 (step S221; Yes), the measurement node 2D stores the group ID in the group ID table 261 of the storage unit 260 (step S222).

FIG. 15 is a flowchart showing an example of a buffering upper limit setting process executed by the information processing apparatus 5 as an operation of the wireless communication system 1 according to the first embodiment.

The information processing apparatus 5 calculates the buffering upper limit value Nu based on the number of relay node groups (number of node groups) Ng and the number of measurement nodes Nm (step S301). The information processing device 5 transmits the buffering upper limit value Nu to each node group NG of the relay nodes 2A to 2C (step S302).

FIG. 16 is a flowchart showing an example of the buffering upper limit setting process executed by the relay nodes 2A to 2C as the operation of the wireless communication system 1 according to the first embodiment.

The relay nodes 2A to 2C wait for the buffering upper limit value Nu transmitted from the information processing device 5 (step S311; No). Here, when the relay nodes 2A to 2C receive the buffering upper limit value Nu transmitted from the information processing apparatus 5 (step S311; Yes), the relay nodes 2A to 2C store the buffering upper limit value Nu in the storage unit 260 (step S312). ..

FIG. 17 is a flowchart showing an example of an operation process executed by the information processing apparatus 5 as an operation of the wireless communication system 1 according to the first embodiment.

When the information processing device 5 is in the sleep state, the intermittent operation of the information processing device 5 is a stop section. That is, the intermittent operation of the information processing device 5 is not a collection cycle (step S401; No).

When the information processing device 5 wakes up from the sleep state, the intermittent operation of the information processing device 5 shifts from the stop section to the operation section. That is, the intermittent operation of the information processing device 5 becomes the collection cycle (step S401; Yes). In this case, the information processing device 5 transmits a data request to the node group NG (step S402).

The information processing device 5 waits for data transmitted from each node group NG (step S403; No). Here, the information processing device 5 receives the data transmitted from each node group NG (step S403; Yes).

The information processing device 5 determines, for example, whether or not a user has instructed a stop command (step S404). The information processing apparatus 5 goes into the sleep state (step S405) when the user does not instruct the stop command (step S404; No) and the sleep state time is reached. That is, the intermittent operation of the information processing device 5 shifts from the operation section to the stop section. When the user gives an instruction for a stop command (step S404; Yes), the information processing device 5 transmits a stop command to each node 2 and ends the operation process (step S406).

FIG. 18 is a flowchart showing an example of an operation process executed by the duty node among the relay nodes 2A to 2C as the operation of the wireless communication system 1 according to the first embodiment.

When the relay node 2A, which is the duty node, receives the data request transmitted from the information processing device 5 (step S411; Yes) and buffers the data (step S412; Yes), the relay node 2A transmits the data. (Step S413). On the other hand, when the relay node 2A receives the data request transmitted from the information processing device 5 (step S411; Yes), if the data is not buffered (step S412; No), step S413 is not executed.

Next, the relay node 2A, which is the duty node, receives the data transmitted from the measurement node 2D (step S414; Yes). Alternatively, the relay node 2A does not receive the data request transmitted from the information processing apparatus 5 (step S411; No), but receives the data transmitted from the measurement node 2D (step S414; Yes). In this case, the relay node 2A determines whether or not the number of buffered data is the buffering upper limit value (step S415). Here, when the number of data is not the buffering upper limit value (step S415; No), the relay node 2A buffers the data transmitted from the measurement node 2D (step S416). On the other hand, when the number of data is the upper limit of buffering (step S415; Yes), the relay node 2A transfers the data to the parent node group NG (step S417).

Next, the relay node 2A, which is a duty node, receives information on the remaining battery level (remaining power amount) transmitted from the relay nodes 2B and 2C, which are non-duty nodes (step S418; Yes). Alternatively, the relay node 2A does not receive the data transmitted from the measurement node 2D (step S414; No), but receives the battery remaining amount information transmitted from the relay nodes 2B and 2C (step S418; Yes). At this time, the remaining battery level of the own node is equal to or less than the threshold value (step S419; Yes), and the remaining battery level from the relay nodes 2B and 2C is equal to or higher than a certain value (step S420; Yes). In this case, the relay node 2A transmits the duty signal to one of the relay nodes 2B and 2C (for example, the relay node 2B) (step S421). At this time, if the data is buffered, the relay node 2A transmits the data to the relay node 2B. Further, when the relay node 2A transmits the duty signal, the relay node 2A erases the duty signal from the storage unit 260 and recognizes that its role (setting) is the duty node. That is, the relay node 2A changes its role (setting) to the non-duty node (step S422).

Here, if the remaining battery level of the relay node 2A, which is the on-duty node, is not equal to or less than the threshold value (step S419; No), steps S420 to S422 are not executed. Further, when the remaining battery level from the relay nodes 2B and 2C is not equal to or higher than a certain value (steps S420; No), steps S421 to S422 are not executed.

When the relay node 2A receives the stop command transmitted from the information processing device 5 (step S423; Yes), the relay node 2A ends the operation process. Alternatively, when the relay node 2A receives the stop command transmitted from the information processing device 5 without receiving the information on the remaining battery level transmitted from the relay nodes 2B and 2C (step S418; No) (step S423; Yes), a stop command is transmitted to the relay nodes 2B and 2C in the node group NG and the child node group NG (step S426), and the operation process is terminated.

If the relay node 2A does not receive the stop command transmitted from the information processing device 5 (step S423; No) and is the on-duty node itself (step S424; Yes), step S411 is executed. On the other hand, the relay node 2A is not the on-duty node itself (step S424; No), but is in the sleep state. In this case, the relay node 2A goes to sleep and executes the operation process of the non-duty node (step S425).

FIG. 19 is a flowchart showing an example of an operation process executed by a non-duty node among the relay nodes 2A to 2C as an operation of the wireless communication system 1 according to the first embodiment.

When the relay nodes 2B and 2C, which are non-duty nodes, are in the sleep state, the intermittent operation of the relay nodes 2B and 2C is a stop section. That is, the intermittent operation of the relay nodes 2B and 2C is not the activation cycle (step S431; No).

When the relay nodes 2B and 2C, which are non-duty nodes, wake up from the sleep state, the intermittent operation of the relay nodes 2B and 2C shifts from the stop section to the operation section. That is, the intermittent operation of the relay nodes 2B and 2C becomes the activation cycle (step S431; Yes). In this case, the relay nodes 2B and 2C transmit the battery remaining amount information to the relay node 2A which is the duty node (step S432).

When the relay nodes 2B and 2C, which are the non-duty nodes, receive the stop command transmitted from the information processing device 5 (step S433; Yes), the operation process ends.

When the relay node 2C, which is a non-duty node, does not receive the stop command transmitted from the information processing device 5 (step S433; No) and does not receive the duty signal from the relay node 2A, which is the duty node (step S434; No). ), The relay node 2C is in the sleep state. In this case, the relay node 2C goes to sleep (step S435), and step S431 is executed.

The relay node 2C, which is a non-duty node, does not receive the stop command transmitted from the information processing device 5 (step S433; No), but receives the duty signal from the relay node 2A, which is the duty node (step S434; Yes). ), The relay node 2B stores the duty signal in the storage unit 260, and recognizes that its role (setting) is the duty node (step S436). In this case, the relay node 2B executes the operation process of the on-duty node.

FIG. 20 is a flowchart showing an example of an operation process executed by the measurement node 2D as the operation of the wireless communication system 1 according to the first embodiment.

When the measurement node 2D is in the sleep state, the intermittent operation of the measurement node 2D is a stop section. That is, the intermittent operation of the measurement node 2D is not the measurement cycle (step S441; No).

When the measurement node 2D wakes up from the sleep state, the intermittent operation of the measurement node 2D shifts from the stop section to the operation section. That is, the intermittent operation of the measurement node 2D becomes the measurement cycle (step S441; Yes). In this case, the measurement node 2D measures the state of the measurement target and transmits it as data to the node group NG (step S442).

When the measurement node 2D receives the stop command transmitted from the information processing device 5 (step S443; Yes), the measurement node 2D ends the operation process.

The measurement node 2D does not receive the stop command transmitted from the information processing device 5 (step S443; No), and enters the sleep state time. In this case, the measurement node 2D goes to sleep (step S444), and step S441 is executed.

[effect]
According to the above description, the wireless communication system 1 according to the first embodiment has an information processing device 5 and a node 2. The node 2 performs an intermittent operation that periodically repeats the operation section and the sleep section. The information processing device 5 collects data from the node 2. Specifically, the group setting unit 501 of the information processing device 5 sets the same node group NG for the nodes 2 (relay nodes 2A to 2C) whose mutual communication quality is equal to or higher than a certain value. When the own node (relay node 2A) is set as the duty node in the node group NG, the operation control unit 203 of the relay node 2A receives data or requests from the information processing device 5. Data is transmitted to the information processing device 5 according to the above. The operation control unit 503 of the information processing apparatus 5 collects data from the relay node 2A set as the duty node among the plurality of relay nodes 2A to 2C in the node group NG.

Further, in the wireless communication system 1 according to the first embodiment, the group setting unit 501 of the information processing device 5 transmits a duty signal for setting the duty node to the one relay node 2A in the node group NG. When the group setting unit 201 of the relay node 2A receives the duty signal transmitted from the information processing apparatus 5, the group setting unit 201 sets its own node (relay node 2A) as the duty node. The group setting unit 201 of the relay nodes 2B and 2C sets its own node (relay nodes 2B and 2C) as a non-duty node when it does not receive the duty signal.

Further, in the wireless communication system 1 according to the first embodiment, when the own node (relay node 2A) is set as the duty node in the node group NG, the remaining power amount of the own node (relay node 2A) is equal to or less than the threshold value. Is. Further, the amount of remaining power notified from the relay nodes 2B and 2C other than the own node (relay node 2A) in the node group NG is a certain value or more. In this case, the operation control unit 203 of the relay node 2A transmits a duty signal to one relay node 2B other than the own node (relay node 2A) in the node group NG, and sets the own node (relay node 2A). Change from a duty node to a non-duty node.

Further, in the wireless communication system 1 according to the first embodiment, the operation control unit 203 of the relay node 2B has a node group NG when its own node (relay node 2B) is set as a non-duty node in the node group NG. The duty signal is received from the relay node (relay node 2A) which is the duty node in the above. In this case, the operation control unit 203 of the relay node 2B changes the setting of the own node (relay node 2B) from the non-duty node to the duty node.

Further, in the wireless communication system 1 according to the first embodiment, the upper limit setting unit 502 of the information processing device 5 notifies each node group NG of the upper limit value of buffering. Specifically, the upper limit setting unit 502 of the information processing apparatus 5 has a buffering upper limit based on the number of node groups NG (number of node groups Ng) and the number of measurement nodes 2D for measuring data (number of measurement nodes Nm). Calculate the value Nu. Then, the upper limit setting unit 502 of the information processing device 5 notifies each node group NG of the buffering upper limit value Nu. The upper limit setting unit 202 of the relay nodes 2A to 2C in the node group NG sets the buffering upper limit value Nu transmitted from the information processing device 5. Therefore, when the own node is set as the duty node in the node group NG, the operation control unit 203 of the relay node 2A receives the data measured by the measurement node 2D and buffers the received data. When the number of buffered data is the buffering upper limit value Nu, the operation control unit 203 of the relay node 2A transfers the data transmitted from the child group to the parent node group NG.

In the wireless communication system 1 according to the first embodiment, in the information processing apparatus 5, the power consumption is reduced by shifting to the sleep section (stop section), which is low power consumption, except for the operation section (data collection section). be able to. In particular, in the wireless communication system 1 according to the first embodiment, the power consumption can be reduced by setting the stop section longer than the operation section (data collection section) in the information processing device 5.

Therefore, in the wireless communication system 1 according to the first embodiment, the relay nodes 2A to 2C change the roles of the duty nodes in the node group NG. Therefore, in the wireless communication system 1 according to the first embodiment, even if the stop section of the information processing device 5 is set to be long, the timing of the operation section (data collection section) of the information processing device 5 is the relay nodes 2A to 2C. It suffices to match the timing of the operation section of any of the duty nodes. Therefore, in the wireless communication system 1 according to the first embodiment, the information processing device 5 can avoid the problem that the data relayed from the relay nodes 2A to 2C cannot be collected in the operation section (data collection section).

Therefore, according to the wireless communication system 1 according to the first embodiment, it is possible to avoid the trouble of data collection while reducing the power consumption.

In the wireless communication system 1 according to the first embodiment, in the operation process, the duty node is changed to another relay node when the remaining battery level of the duty node among the relay nodes 2A to 2C is equal to or less than the threshold value. Not limited to. For example, in the wireless communication system 1 according to the second embodiment, the duty nodes of the relay nodes 2A to 2C may be ordered in the operation process. In the second embodiment, the same parts as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

[Operation of wireless communication system]
FIG. 21 is a flowchart showing an example of a group setting process executed by the information processing apparatus 5 as an operation of the wireless communication system 1 according to the second embodiment.

First, the information processing apparatus 5 executes steps S201 to S205 in the same manner as in the first embodiment (see FIG. 12). Then, the information processing apparatus 5 transmits a node list of the same node group NG to the duty node of each node group NG (step S1200).

For example, the node list includes IDs that identify relay nodes 2A to 2C in the node group NG. Examples of these IDs include MAC addresses. For example, among the MAC addresses of the relay nodes 2A to 2C, the MAC address of the relay node 2A is the largest and the MAC address of the relay node 2C is the smallest. In this case, in the order of the duty nodes, the relay node 2A becomes the first duty node, the relay node 2B becomes the second duty node, and the relay node 2C becomes the third duty node. The duty nodes are repeated in the order of relay nodes 2A to 2C for the fourth and subsequent nodes. Therefore, the node list is transmitted to the relay node 2A, which is the first on-duty node.

FIG. 22 is a flowchart showing an example of a group setting process executed by the duty node among the relay nodes 2A to 2C as the operation of the wireless communication system 1 according to the second embodiment.

First, the relay node 2A, which is the duty node, executes steps S211 to S216 in the same manner as in the first embodiment (see FIG. 13).

Next, the relay node 2A, which is the duty node, waits for the node list transmitted from the information processing device 5 (step S1211; No). Here, when the relay node 2A receives the node list transmitted from the information processing device 5 (step S1211; Yes), the relay node 2A stores the node list in the storage unit 260 and sets the node in the non-duty node of the same node group NG. Send the list (step S1212). The relay node 2A determines the relay node 2B to be the on-duty node next to its own node based on the MAC address in the node list stored in the storage unit 260 (step S1213).

FIG. 23 is a flowchart showing an example of group setting processing executed by the non-duty node among the relay nodes 2A to 2C as the operation of the wireless communication system 1 according to the second embodiment.

First, the relay nodes 2B and 2C, which are non-duty nodes, execute steps S211 to S215 in the same manner as in the first embodiment (see FIG. 13).

Next, the relay nodes 2B and 2C, which are non-duty nodes, wait for the node list transmitted from the information processing device 5 (step S1221; No). Here, when the relay nodes 2B and 2C receive the node list transmitted from the information processing device 5 (step S1221; Yes), the relay nodes 2B and 2C store the node list in the storage unit 260. Here, the relay node 2B determines the relay node 2C, which is the on-duty node next to its own node, based on the MAC address in the node list stored in the storage unit 260. Further, the relay node 2C determines the relay node 2A to be the duty node next to its own node based on the MAC address in the node list stored in the storage unit 260 (step S1222).

FIG. 24 is a flowchart showing an example of an operation process executed by the duty node among the relay nodes 2A to 2C as the operation of the wireless communication system 1 according to the second embodiment.

First, the relay node 2A, which is the duty node, executes steps S411 to S417 in the same manner as in the first embodiment (see FIG. 18).

Next, the relay node 2A, which is the on-duty node, receives the wake-up notification transmitted from the same node group NG (step S1411; Yes). At this time, the remaining battery level of the own node is equal to or less than the threshold value (step S1412; Yes), and the wake-up notification transmitted from the same node group NG is wake-up from the relay node 2B, which is the duty node next to the own node. It is a notification (step S1413; Yes). In this case, the relay node 2A executes steps S421 to S425 in the same manner as in the first embodiment (see FIG. 18). Here, if the remaining battery level of the own node is not equal to or less than the threshold value (step S1412; No), steps S1413, S421, and S422 are not executed.

On the other hand, the wake-up notification transmitted from the same node group NG is not the wake-up notification from the relay node 2B, which is the on-duty node next to its own node (step S1412; No). In this case, steps S421 to S422 are not executed.

Further, when the relay node 2A receives the stop command transmitted from the information processing device 5 without receiving the wake-up notification transmitted from the same node group NG (step S1411; No) (step S423; Yes). A stop command is transmitted to the relay nodes 2B and 2C in the node group NG and the child node group NG (step S426), and the operation process is terminated.

FIG. 25 is a flowchart showing an example of an operation process executed by the non-duty node among the relay nodes 2A to 2C as the operation of the wireless communication system 1 according to the second embodiment.

First, the relay nodes 2B and 2C, which are non-duty nodes, execute step S431 in the same manner as in the first embodiment (see FIG. 19).

Next, when the intermittent operation of the relay nodes 2B and 2C becomes the activation cycle, the relay nodes 2B and 2C transmit a wake-up notification to the relay node 2A which is the duty node (step S2411).

After that, the relay nodes 2B and 2C, which are non-duty nodes, execute steps S433 to S437 in the same manner as in the first embodiment (see FIG. 19).

[effect]
According to the above description, in the wireless communication system 1 according to the second embodiment, the duty nodes are sequentially set in the node group NG. Specifically, when the own node (relay node 2A) is set as the on-duty node in the node group NG, the remaining power amount of the own node (relay node 2A) is equal to or less than the threshold value. Further, the operation control unit 203 of the relay node 2A receives a wake-up notification from the relay nodes 2B and 2C other than the own node (relay node 2A) in the node group NG. In this case, the operation control unit 203 of the relay node 2A transmits a duty signal to one relay node 2B other than the own node (relay node 2A) in the node group NG, and sets the own node (relay node 2A). Change from a duty node to a non-duty node.

In the wireless communication system 1 according to the second embodiment, the same effect as that of the first embodiment is realized even when the duty nodes of the relay nodes 2A to 2C are arranged in order. That is, according to the wireless communication system 1 according to the second embodiment, it is possible to avoid problems in data collection while reducing power consumption.

[Other Examples]
The communication quality in Examples 1 and 2 is not limited to, for example, LQI, and may be another index.

Further, each component in Examples 1 and 2 does not necessarily have to be physically configured as shown in the drawing. That is, the specific form of distribution / integration of each part is not limited to the one shown in the figure, and all or part of them are functionally or physically distributed / integrated in arbitrary units according to various loads and usage conditions. Can be configured.

Further, various processes performed by each device execute all or any part thereof on a CPU (Central Processing Unit) (or a microcomputer such as an MPU (Micro Processing Unit) or an MCU (Micro Controller Unit)). You may try to do it. Further, various processes may be executed in whole or in any part on a program analyzed and executed by a CPU (or a microcomputer such as an MPU or MCU) or on hardware by wired logic.

The node 2 and the information processing device 5 in the first and second embodiments can be realized by, for example, the following hardware configuration.

FIG. 26 is a diagram showing an example of the hardware configuration of the node 2. Node 2 shown in FIG. 26 has a processor 2001, a memory 2002, and an analog circuit 2003. Examples of the processor 2001 include a CPU, a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), and the like. Further, examples of the memory 2002 include RAM (Random Access Memory) such as SDRAM (Synchronous Dynamic Random Access Memory), ROM (Read Only Memory), flash memory, and the like.

The MCU 200 of FIG. 2 is realized by the processor 2001, and the storage unit 260 of FIG. 2 is realized by the memory 2002. For example, the various processes performed by the node 2 in the first and second embodiments are realized by executing a program stored in various memories such as a non-volatile storage medium by the processor. For example, a program corresponding to each process executed by the MCU 200 of FIG. 2 is recorded in the memory 2002, and each program is executed by the processor 2001. Further, for example, the sensor element 210, the energy harvesting element 220, the battery 230, the power supply control unit 240, and the wireless unit 250 in FIG. 2 are realized by the analog circuit 2003.

Although various processes performed by the node 2 in the first and second embodiments are assumed to be executed by one processor 2001, the present invention is not limited to this, and may be executed by a plurality of processors.

FIG. 27 is a diagram showing an example of the hardware configuration of the information processing device 5. The information processing device 5 shown in FIG. 27 includes a processor 5001, a memory 5002, and an analog circuit 5003. Examples of the processor 5001 include a CPU, DSP, FPGA and the like. Further, examples of the memory 5002 include RAM such as SDRAM, ROM, flash memory, and the like.

The MCU 500 of FIG. 4 is realized by the processor 5001, and the storage unit 560 of FIG. 4 is realized by the memory 5002. For example, various processes performed by the information processing apparatus 5 in Examples 1 and 2 are realized by executing a program stored in various memories such as a non-volatile storage medium by a processor. For example, a program corresponding to each process executed by the MCU 500 of FIG. 4 is recorded in the memory 5002, and each program is executed by the processor 5001. Further, for example, the energy harvesting element 520, the battery 530, the power supply control unit 540, and the communication unit 550 of FIG. 4 are realized by the analog circuit 5003.

Although various processes performed by the information processing device 5 in Examples 1 and 2 are assumed to be executed by one processor 5001, the present invention is not limited to this, and may be executed by a plurality of processors.

1 Wireless communication system 2,2-1 to 2-31 node 3 GW
4 Aggregator 5 Information processing device 200 MCU
201 Group setting unit 202 Upper limit setting unit 203 Operation control unit 204 Control unit 210 Sensor element 220 Energy harvesting element 230 Battery 240 Power control unit 250 Radio unit 260 Storage unit 261 Group ID table 262 LQI table 500 MCU
501 Group setting unit 502 Upper limit setting unit 503 Operation control unit 504 Control unit 520 Energy harvesting element 530 Battery 540 Power supply control unit 550 Communication unit 560 Storage unit

Claims (11)

An information processing device that collects data from nodes that perform intermittent operations that periodically repeat an operation section and a sleep section.
A group setting unit that sets the same group for nodes whose mutual communication quality is above a certain value,
Among the nodes in the group, the operation control unit that collects data from the nodes set for the duty node that is the operation section, and
An information processing device characterized by having. The group setting unit transmits a duty signal for setting the duty node to one node in the group.
The information processing apparatus according to claim 1. An upper limit setting unit that calculates the buffering upper limit value based on the number of the groups and the number of measurement nodes that measure data, and notifies each group.
With more
In each of the groups, when the number of data buffered by the duty node is the buffering upper limit, the data transmitted from the child group is transferred to the parent group.
The information processing apparatus according to claim 1 or 2. A node that periodically repeats an operation section and a sleep section to perform intermittent operations and send data to an information processing device.
If the local node is set to the duty node that is the operation section in the group set for the nodes whose mutual communication quality is equal to or higher than a certain value, data is received or from the information processing device. Operation control unit that transmits data to the information processing device in response to a request,
A node characterized by having. A setting unit that sets the own node to the duty node when receiving the duty signal transmitted from the information processing device, and sets the own node to the non-duty node when the duty signal is not received.
The node according to claim 4, further comprising. When the own node is set to the duty node in the group, the operation control unit has a node other than the own node in the group and the remaining power amount of the own node is equal to or less than the threshold value. When the remaining power amount notified from is equal to or more than a certain value, the duty signal is transmitted to one node other than the own node in the group, and the setting of the own node is set from the duty node to the non-duty node. Change to
The node according to claim 5. The duty nodes are set in order within the group,
When the own node is set to the duty node in the group, the operation control unit has a node other than the own node in the group and the remaining power amount of the own node is equal to or less than the threshold value. When the wake-up notification is received from, the duty signal is transmitted to one node other than the own node in the group, and the setting of the own node is changed from the duty node to the non-duty node.
The node according to claim 5. When the own node is set to the non-duty node in the group and the operation control unit receives the duty signal from the node which is the duty node in the group, the operation control unit sets the own node. Is changed from the non-duty node to the duty node,
The node according to claim 6 or 7. Upper limit setting unit for setting the upper limit of buffering transmitted from the information processing device,
With more
When the own node is set to the duty node in the group, the operation control unit buffers the received data, and the number of the buffered data is the buffering upper limit value. , Transfer data sent from the child group to the parent group,
The node according to claim 4. A node that performs intermittent operation that periodically repeats the operation section and sleep section,
An information processing device that collects data from the node and
Have,
The information processing device
A group setting unit that sets the same group for nodes whose mutual communication quality is above a certain value,
Among the nodes in the group, the operation control unit that collects data from the nodes set for the duty node that is the operation section, and
A wireless communication system characterized by having. An information processing device that collects data from nodes that perform intermittent operations that periodically repeat operation sections and sleep sections.
Set in the same group for nodes whose mutual communication quality is above a certain value,
Among the nodes in the group, data is collected from the node set as the duty node that is the operation section.
A wireless network control method characterized by performing processing.

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