JP2014086776A - Management node, program, and radio communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio communication system which avoids isolation of a node configuring the system even when change of communication environment causes change of environment of the radio communication system.SOLUTION: A radio communication system is configured by two or more nodes. The radio communication system includes a management node (coordinator) for managing the radio communication system. For each relay node (coordinator or router) for transferring data to another node in the radio communication system, the management node sets a group composed of the relay node and a node directly communicating with the relay node and acquires communication strength at each node in the radio communication system. The management node outputs an instruction to a node in a specific group including a node in the radio communication system whose communication strength acquired by acquisition means is lower than predetermined strength, so that a function of the node in the specific group is changed to that of a relay node to reconfigure the network.

Description

  The present invention relates to a management node, a program, and a wireless communication system, and in particular, a management node that configures a wireless communication system including two or more nodes, a program for causing a computer to function as such a management node, and The present invention relates to such a wireless communication system.

  Conventionally, wireless communication systems have been adopted in a wide range such as communication in mobile terminals. As an example of such a system, a communication system including a plurality of power consumption measuring devices (hereinafter also referred to as “taps”) and a control device for controlling the plurality of power consumption measuring devices for power saving in the home. It has been known. Such a communication system generally employs a short-range wireless communication system. An example of the communication method is ZigBee (registered trademark).

  Nodes existing in the ZigBee (registered trademark) network are classified into a coordinator, a router, and an end device. One coordinator always exists in the network, and is a node that flows and receives data outside the network and has a network management function. Management functions include network startup, device joining / leaving / rejoining, logical network address allocation, routing, routing maintenance, security level setting, and the like. A router is a node that controls communication so that data can be efficiently and stably delivered to a target node in multi-hopping in which data is transferred over a plurality of stages. An end device is a node located at the end of the network. The end device does not transfer data.

  ZigBee (registered trademark) constructs a tree-type network having a coordinator as a vertex. In ZigBee (registered trademark), an end device with a low received signal strength that is located away from the coordinator and the router cannot participate in the network.

  Various techniques have been proposed for the construction of such a wireless communication network. For example, in Patent Document 1 (Japanese Translation of PCT International Publication No. 2011-504673), each user equipment that communicates via a base station is caused to scan a communication area adjacent to a communication area where each user equipment exists, thereby Techniques for building adjacency relationships are disclosed.

Special table 2011-504474 gazette

  However, even if the conventional technique disclosed in Patent Document 1 is applied to a general communication system including a parent device (server) and a child device (client), it is partially due to movement of the parent device in the communication area. It is assumed that no child device can join the network. Even if the technology is applied to a ZigBee (registered trademark) network, if the coordinator or router moves away from the end device, or if the end device and the coordinator or router with which the end device communicates directly, When an obstacle is added, the end device cannot join the network.

  The present invention has been conceived in view of such circumstances, and the purpose of the present invention is to change the system of the wireless communication system even when the environment of the wireless communication system changes due to the change of the communication environment. It is to avoid the isolation of the nodes that make up.

  A management node according to a certain aspect is a management node that manages a wireless communication system including two or more nodes. The management node includes, for each relay node that transfers data to other nodes in the wireless communication system, a setting unit that sets a group including nodes that directly communicate with the relay node; and each node of the wireless communication system Acquiring means for acquiring communication strength in the wireless communication system, specifying means for specifying a node whose communication strength acquired by the acquiring means is below a predetermined strength among nodes of the wireless communication system, and specifying to which the node specified by the specifying means belongs And an instruction unit that outputs an instruction to reconfigure the network by changing the function to the relay node.

  Preferably, the instruction unit does not output an instruction to a node functioning as a relay node in a group different from the specific group among nodes belonging to the specific group.

  A program according to another aspect is a program executed by a computer of a management node that manages a wireless communication system including two or more nodes. The program sets, for each relay node that performs data transfer to another node in the wireless communication system, a group configured by a node that directly communicates with the relay node; Obtaining a communication strength at a node; identifying a node having a communication strength less than a predetermined strength among nodes of a wireless communication system; and specifying a node to which a node having a communication strength less than a predetermined strength belongs Causing the node of the group to execute an instruction to change the function to the relay node and reconstruct the network.

  The management method of the radio | wireless communications system according to another situation is performed by the computer of the management node which manages the radio | wireless communications system comprised by two or more nodes. A method for managing a wireless communication system includes a step of setting a group constituted by a node that directly communicates with a relay node for each relay node that transfers data to another node in the wireless communication system; The step of acquiring the communication strength at each of the nodes, the step of identifying the node whose acquired communication strength is lower than the predetermined strength among the nodes of the wireless communication system, and the node whose communication strength is lower than the predetermined strength belong Outputting a command for changing the function to the relay node and reconstructing the network to a specific group of nodes.

  A wireless communication system according to still another aspect is a wireless communication system including two or more nodes. The two or more nodes include a management node that manages the wireless communication system. The management node includes, for each relay node that transfers data to other nodes in the wireless communication system, a setting unit that sets a group including nodes that directly communicate with the relay node; and each node of the wireless communication system Acquiring means for acquiring communication strength in the wireless communication system, specifying means for specifying a node whose communication strength acquired by the acquiring means is below a predetermined strength among nodes of the wireless communication system, and specifying to which the node specified by the specifying means belongs And an instruction means for outputting an instruction to reconfigure the network by changing the function to the relay node.

  Preferably, after the reconfiguration, the relay node outputs an instruction to function as an end node to the node that has become the end by the reconfiguration.

  According to an aspect, the nodes constituting the wireless communication system are grouped for each relay node, and reconstruction is performed for each group. Further, at the time of the reconfiguration, the node of the group is instructed to change the function to the relay node.

  As a result, it is possible to reconstruct a network only for a group in which a communication failure has occurred without wastefully reconstructing a network in which no communication failure has occurred. Therefore, the network can be reconstructed efficiently.

  In addition, the function of the node (child device) can be dynamically changed within the group. Therefore, since the communication mode within a group can be flexibly set according to the communication environment that the group is facing, it is possible to more reliably avoid isolation of nodes (child devices).

It is the figure which showed schematic structure of the network which concerns on embodiment of this invention. It is a figure showing the external appearance of a monitor. It is a block diagram of a monitor. It is a perspective view of a tap. It is a figure showing the hardware constitutions of the tap. It is a figure showing the hardware constitutions of the tablet terminal. It is a figure for demonstrating the mounting method in a tap and a monitor. It is a figure for demonstrating the mounting method in a tablet terminal. It is a figure which shows the structure of the network Z using a tablet terminal instead of a monitor, a personal computer, and a tablet terminal. It is a block diagram of a tablet terminal. It is a figure showing the function structure of the low-speed radio | wireless communication module. It is a figure showing the function structure of the low-speed radio | wireless communication module. It is a figure which shows typically an example of the node group which comprises a radio | wireless communications system. It is a figure which shows an example of grouping with respect to a radio | wireless communications system. It is a figure for demonstrating the outline | summary of the network reconstruction process in 1st Embodiment. It is a figure for demonstrating the outline | summary of the network reconstruction process in 1st Embodiment. It is a figure for demonstrating the outline | summary of the network reconstruction process in 1st Embodiment. FIG. 18 is a flowchart of network reconfiguration processing shown in FIGS. 15 to 17. FIG. It is a figure for demonstrating the aspect of the reconstruction of the network of 2nd Embodiment. It is a figure showing the function structure of the radio | wireless RF built-in communication controller part of 2nd Embodiment. It is a figure which shows typically the specific example of the content of the network optimization information in 2nd Embodiment. It is a figure which shows typically the specific example of the content of the network optimization information in 2nd Embodiment. It is a figure for demonstrating the content of the reconstruction process of the network in 2nd Embodiment. It is a figure for demonstrating the content of the reconstruction process of the network in 2nd Embodiment. It is a figure for demonstrating the content of the reconstruction process of the network in 2nd Embodiment.

  Hereinafter, a network including an embodiment of a relay node and a wireless communication system including the relay node will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

[First Embodiment]
<A. Network Overview>
FIG. 1 is a diagram showing a schematic configuration of a network according to an embodiment of the present invention. Referring to FIG. 1, a network Z represents a low-speed wireless communication network (mainly assuming ZigBee (registered trademark)). The network E indicates a high-speed communication network (mainly assuming Ethernet (registered trademark) or WiFi (registered trademark)). In the present embodiment, the wireless communication system means, for example, at least a part of hardware elements constituting a low-speed wireless communication network.

  The network Z includes a monitor 1001 having a HyperText Transfer Protocol (HTTP) server function, a broadband router 1002, a personal computer 1003, a plurality of taps 1004a, 1004b, and 1004c, and a plurality of home appliances (air conditioner 1005, refrigerator 1006). , Television 1007 and the like) and a tablet terminal 1008.

  The power plug 1051 of the air conditioner 1005 is inserted into the socket of the tap 1004a. Similarly, the power plug 1061 of the refrigerator 1006 is inserted into the socket of the tap 1004b. Further, the power plug 1071 of the television 1007 is inserted into the socket of the tap 1004c.

  Taps 1004a, 1004b, and 1004c are respectively attached to outlets 1015, 1016, and 1017 installed in the house. Thereby, the taps 1004a, 1004b, and 1004c are supplied with power.

  The taps 1004a, 1004b, and 1004c are power consumption measuring devices that measure the power consumption of each home appliance connected to each of the taps 1004a, 1004b, and 1004c. For example, the tap 1004a measures the power consumption of the air conditioner 1005. Each of the taps 1004a, 1004b, and 1004c transmits the measured power consumption to the monitor 1001. In the following description, for convenience of description, when the taps 1004a, 1004b, and 1004c are expressed without distinction, they are expressed as “tap 1004”.

  Each of the monitor 1001 and the plurality of taps 1004 includes a low-speed wireless communication module. The monitor 1001 and the plurality of taps 1004 constitute a low-speed wireless communication network Z (hereinafter also simply referred to as “network Z”). The monitor 1001 is connected to the broadband router 1002 by Ethernet (registered trademark). The monitor 1001 functions as a gateway for the network Z. The monitor 1001 wirelessly communicates with a plurality of taps 1004 at a low speed.

  The broadband router 1002 may be connected to the Internet. The personal computer 1003 is connected to the broadband router 1002 by Ethernet (registered trademark). The personal computer 1003 may be connected to the broadband router 1002 by WiFi (registered trademark).

  The personal computer 1003 is a general personal computer on which a browser (HTTP client) operates. The personal computer 1003 communicates with the HTTP server of the monitor 1001 via the browser of the personal computer 1003. In this way, the personal computer 1003 can make various settings for the monitor 1001. With the functions of the HTTP server and the HTTP client, even a monitor 1001 having only a poor input device can perform complicated settings.

  The tablet terminal 1008 communicates with the monitor 1001 via the broadband router 1002. The tablet terminal 1008 is connected to the broadband router 1002 by WiFi (registered trademark). Note that the tablet terminal 1008 may be connected to the broadband router 1002 by Ethernet (registered trademark).

  The tablet terminal 1008 can perform various displays regarding power consumption. The tablet terminal 1008 can display power consumption in the network Z, for example. Moreover, the tablet terminal 1008 can display the power consumption of the household appliance selected by the user, for example.

  Below, the example using ZigBee (trademark) which is one of the short-range wireless communication standards for household appliances as the network Z is demonstrated. ZigBee (registered trademark) has lower speed and shorter transmission distance than Bluetooth (registered trademark), but has an advantage of power saving and low cost.

<B. Configuration of Monitor 1001>
FIG. 2 is a diagram illustrating the appearance of the monitor 1001. FIG. 2A is a perspective view of the monitor 1001. FIG. 2B is a side view of the monitor 1001. FIG. 2C is an enlarged view of a main part of another side surface of the monitor 1001.

  Referring to FIG. 2A, the monitor 1001 includes a light emitting unit 1103 and an antenna 1107. The light emitting unit 1103 includes three LEDs (Light Emitting Diodes) 1103a, 1103b, and 1103c for displaying the operating state of the monitor 1001 and the like.

  The LED 1103a is a light emitting element (power LED) for indicating whether the monitor 1001 is on or off. The LED 1103b is a light emitting element (tap LED) for displaying a communication state with the tap 1004. The LED 1103 c is a light emitting element (router LED) for displaying a communication state with the broadband router 1002.

  The antenna 1107 is used for the monitor 1001 to communicate with the taps 1004a, 1004b, and 1004c.

  Referring to FIG. 2B, the monitor 1001 further includes a pairing button 1108 on the surface opposite to the surface on which the light emitting unit 1103 is provided. The pairing button 1108 is a button for changing the monitor 1001 to the pairing permission state.

  Referring to FIG. 2C, the monitor 1001 further includes a slide switch 1109 on a surface different from the surface where the light emitting unit 1103 is provided and the surface where the pairing button 1108 is provided. The slide switch 1109 slides by a user operation. The slide switch 1109 can take any one of a pairing position, a normal position, and a leave position. The slide switch 1109 is used when performing pairing (participation in the network) and leaving (leaving from the network). The slide switch 1109 is set to the normal position during normal use.

  FIG. 3 is a block diagram of the monitor 1001. Referring to FIG. 3, a monitor 1001 includes a control unit 1101, a light emitting unit 1103, a high-speed communication interface unit 1104, a power supply unit 1105, a wireless RF (Radio Frequency) built-in communication controller unit 1106, an antenna 1107, A pairing button 1108, a slide switch 1109, and a reset switch (not shown) are provided.

  A wireless RF built-in communication controller unit 1106 includes a CPU (Central Processing Unit) 1161, a ROM (Read Only Memory) 1162, a RAM (Random Access Memory) 1163, a GPIO (General Purpose Input / Output) 1164, and a wireless RF unit. 1165 and a UART (Universal Asynchronous Receiver Transmitter) 1166 for communicating with the control unit 1101. Note that the wireless RF built-in communication controller unit 1106 corresponds to a ZigBee (registered trademark) coordinator unit. The ROM 1162, the RAM 1163, the UART 1166, the GPIO 1164, and the wireless RF unit 1165 are connected to the CPU 1161, respectively.

  The wireless RF built-in communication controller unit 1106 is connected to the antenna 1107. The wireless RF built-in communication controller unit 1106 controls communication with communication devices existing on the network Z.

  As the OS (Operating System) of the control unit 1101, for example, Linux (registered trademark) can be used. The control unit 1101 includes a high-performance CPU compared to the CPU 1161, and has abundant memory. With this configuration, the monitor 1001 can realize advanced information processing.

  The high-speed communication interface unit 1104 is an interface for communicating with the broadband router 1002 using Ethernet (registered trademark) or WiFi (registered trademark). The power supply unit 1105 supplies power to the control unit 1101 and the wireless RF built-in communication controller unit 1106.

  The control unit 1101 is connected to a light emitting unit 1103, a high-speed communication interface unit 1104, a power supply unit 1105, a wireless RF built-in communication controller unit 1106, a pairing button 1108, and a slide switch 1109. The control unit 1101 controls the overall operation of the monitor 1001. The control unit 1101 accepts inputs from the pairing button 1108 and the slide switch 1109. In addition, the control unit 1101 issues an output instruction to the light emitting unit 1103.

  Next, an outline of operations when the user performs pairing will be described. First, the user slides the slide switch 1109 from the normal position to the pairing position. Thereafter, the user presses the pairing button 1108. Thereby, the monitor 1001 enters the pairing permission state for a predetermined time (for example, 60 seconds). During this time, the control unit 1101 causes the light emitting unit 1103 to emit light in a predetermined state. Then, when the monitor 1001 is in a pairing permission state, the user plugs the tap 1004 into an outlet so that the monitor 1001 and the tap 1004 are paired.

<C. Configuration of Tap 1004>
FIG. 4 is a perspective view of the tap 1004. Referring to FIG. 4, the tap 1004 includes a plug insertion socket 2101, a plug 2102, an LED 2105, and a setting button 2106. When using the tap, the user inserts the power plug of the home appliance into the socket 2101 and inserts the plug 2102 into an outlet installed in the house (see FIG. 1). Note that the shape of the socket 2101 is determined in accordance with the shape of a power plug of a connected home appliance.

  FIG. 5 is a diagram illustrating a hardware configuration of the tap 1004. Referring to FIG. 5, a tap 1004 includes a socket 2101, a plug 2102, a shunt resistor 2103, a power supply unit 2104, an LED 2105, a setting button 2106, an antenna 2107, a power sensor unit 2110, and low-speed wireless communication. A module 2120, a wiring 2131, a wiring 2132, and a wiring 2133 are provided.

  The power sensor unit 2110 includes a voltage input ADC unit 2111, a current input ADC unit 2112, a multiplier 2113, and a digital / frequency conversion unit 2114. The low-speed wireless communication module 2120 includes a CPU 2121, a ROM 2122, a RAM 2123, a GPIO 2124, and a wireless RF unit 2125.

  The wiring 2132 and the wiring 2133 are connected by a shunt resistor 2103. The shunt resistor 2103 is a very small (several hundred micro ohms) resistor used for measuring current.

  The socket 2101 and the plug 2102 are connected by wirings 2131 to 2133 and a shunt resistor 2103. The wiring 2131 is connected to one terminal of the plug 2102 and one terminal of the socket 2101. The wiring 2132 is connected to the other terminal of the plug 2102 and one end of the shunt resistor 2103. The wiring 2133 is connected to the other terminal of the socket 2101 and the other end of the shunt resistor 2103.

  The power supply unit 2104 is connected to the wiring 2132. The power supply unit 2104 converts alternating current into direct current. The power supply unit 2104 gives the DC power obtained by the conversion to the power sensor unit 2110 and the low-speed wireless communication module 2120.

  The voltage input ADC unit 2111 is connected to the wiring 2131 and the wiring 2132. The voltage input ADC unit 2111 outputs the voltage (potential difference) between the wiring 2131 and the wiring 2132 to the multiplier 2113 as a digital signal.

  The current input ADC unit 2112 is connected to the wiring 2132 and the wiring 2133. The current input ADC unit 2112 outputs the current value of the current flowing through the shunt resistor 2103 to the multiplier 2113 as a digital signal.

  The multiplier 2113 multiplies the output from the voltage input ADC unit 2111 and the output from the current input ADC unit 2112, and outputs a digital signal obtained by the multiplication to the digital / frequency conversion unit 2114.

  The digital / frequency converter 2114 converts the input digital signal into a frequency signal. The digital / frequency converter 2114 outputs the frequency signal obtained by the conversion to the GPIO 2124 of the low-speed wireless communication module 2120.

  The CPU 2121 performs data conversion on the frequency signal acquired from the GPIO 2124. The wireless RF unit 2125 transmits a signal obtained by data conversion to the monitor 1001 using the antenna 2107.

  The ROM 2122 stores programs executed by the CPU 2121. The RAM 2123 temporarily stores data processed by the CPU 2121 and processed data.

  The LED 2105 indicates the data processing state of the tap 1004 by a color that blinks and / or turns on. A setting button 2106 is used for initial setting of the tap 1004 by the user.

  The CPU 2121 also converts a signal received via the antenna 2107 as appropriate and uses it for the processing described in this specification.

<D. Configuration of Tablet Terminal 1008>
FIG. 6 is a diagram illustrating a hardware configuration of the tablet terminal 1008. Referring to FIG. 6, tablet terminal 1008 includes a CPU 4010, a touch screen 4020, a clock 4030, a memory 4040, a button 4050, a communication interface 4060, and a speaker 4070. The touch screen 4020 includes a display 4021 and a touch panel (tablet) 4022, and the touch panel 4022 is laid on the surface of the display 4021. However, the tablet terminal 1008 may not include the touch panel 4022.

  The memory 4040 is realized by various types of RAM, ROM, flash memory, hard disk, and the like. The memory 4040 stores an OS, various control programs executed by the CPU 4010, and various data tables such as a table read by the CPU 4010.

  The CPU 4010 executes various kinds of information processing and the like by executing various programs stored in the memory 4040. The program here includes not only a program directly executable by the CPU but also a program in a source program format, a compressed program, an encrypted program, and the like.

  The display 4021 displays the power consumption of each of the home appliances 1005 to 1007 by being controlled by the CPU 4010, for example. The touch panel 4022 detects a touch operation with a user's finger and inputs touch coordinates or the like to the CPU 4010. The CPU 4010 receives a command from the user via the touch panel 4022.

  The button 4050 is disposed on the surface of the tablet terminal 1008. A plurality of buttons such as a determination key, a direction key, and a numeric keypad may be arranged on the tablet terminal 1008. The button 4050 receives a command from the user. A button 4050 inputs a command from the user to the CPU 4010.

  The communication interface 4060 communicates with the monitor 1001 via the broadband router 1002 under the control of the CPU 4010. As described above, the communication interface 4060 communicates with the broadband router 1002 using, for example, WiFi (registered trademark).

  The speaker 4070 outputs sound based on a command from the CPU 4010. For example, the CPU 4010 causes the speaker 4070 to output sound based on the sound data. The clock 4030 inputs the current date and time to the CPU 4010 based on a command from the CPU 4010.

<E. Implementation example>
FIG. 7 is a diagram for explaining a mounting method in the tap 1004 and the monitor 1001. That is, FIG. 7 is a diagram for explaining a software structure in the tap 1004 and the monitor 1001.

  Referring to FIG. 7, the tap 1004 includes a ZigBee (registered trademark) application 3401 and a Z-STACK ZigBee (registered trademark) protocol stack 3402. The ZigBee (registered trademark) application 3401 acquires information on power consumption from a power measurement microcomputer (not shown), and converts the information into a predetermined format. The ZigBee (registered trademark) application 3401 sends information regarding power consumption to the monitor 1001 in the predetermined format. The Z-STACK ZigBee (registered trademark) protocol stack 3402 is a ZigBee (registered trademark) compliant protocol stack for a communication device portfolio and platform using IEEE802.15.4.

  The wireless RF built-in communication controller unit 1106 (ZigBee coordinator unit) of the monitor 1001 includes a ZigBee (registered trademark) application 3111, a Z-STACK ZigBee (registered trademark) protocol stack 3112, and a UART 1166. The ZigBee (registered trademark) application 3111 receives the information regarding the power consumption described above from the tap 1004. The Z-STACK ZigBee (registered trademark) protocol stack 3112 is similar to the Z-STACK ZigBee (registered trademark) protocol stack 3402 in the tap 1004. The ZigBee (registered trademark) for a portfolio of communication devices and platforms using IEEE802.15.4. ) A compliant protocol stack. As described above, the UART 1166 is a transmitter for communicating with the control unit 1101.

  A control unit 1101 (see FIG. 3) of the monitor 1001 includes a ZigBee (registered trademark) manager 3121, a Z-STACK monitor library 3122, a UART 3123, an LED & switch control 3124, and a UDP / IP (User Datagram Protocol / Internet Protocol). A port 12131 and an Ethernet (registered trademark) 3125 are included. The ZigBee (registered trademark) manager 3121 is one of applications stored in the control unit 1101. Note that another application stored in the control unit 1101 is a tap information collection application for collecting information on the tap 1004.

  The ZigBee (registered trademark) manager 3121 manages the nodes of ZigBee (registered trademark). The ZigBee (registered trademark) manager 3121 determines what kind of node exists in the network Z of ZigBee (registered trademark). Furthermore, when there is a change in the ZigBee (registered trademark) node, the ZigBee (registered trademark) manager 3121 detects the change, and notifies the other application of the change.

  The ZigBee (registered trademark) manager 3121 monitors the LED & switch control 3124. Specifically, the ZigBee (registered trademark) manager 3121 is a program for controlling the light emission of the LEDs 1103 a, 1103 b, and 1103 c and processing input from the pairing button 1108 and the slide switch 1109. The ZigBee (registered trademark) manager 3121 takes the form of a server, and when there is an access from another device, it replies to the other device (communication based on the ZigBee upper protocol). Further, the ZigBee (registered trademark) manager 3121 has a function as a monitor discovery server and a function (pairing application) for performing pairing.

  The Z-STACK monitor library 3122 communicates with the wireless RF built-in communication controller unit 1106 by directly exchanging data with the UART 3123. When the UART 3123 transmits data to the wireless RF built-in communication controller unit 1106, the Z-STACK monitor library 3122 receives some response from the wireless RF built-in communication controller unit 1106 via the UART 3123. More specifically, a ZigBee (registered trademark) manager 3121, a tap information collection application, and a device control library 3802 (see FIG. 8) to be described later communicate with ZigBee via the Z-STACK monitor library 3122. Note that some commands transmitted by the Z-STACK monitor library 3122 are for the wireless RF built-in communication controller unit 1106 and others are for the tap 1004.

  The UDP / IP port 12131 is one of UDP / IP ports. The UDP / IP port 12131 converts data into a UDP packet. The UDP / IP port 12131 communicates with the broadband router 1002 using the Ethernet (registered trademark) 3125. For example, the UDP / IP port 12131 uses the Ethernet (registered trademark) 3125 and can perform communication based on the above ZigBee upper layer protocol and the monitor discovery protocol. In this specification, the number “12131” in “UDP / IP port 12131” means a port number.

  FIG. 8 is a diagram for explaining a mounting method in the tablet terminal 1008. That is, FIG. 8 is a diagram for explaining a software structure in the tablet terminal 1008.

  Referring to FIG. 8, a tablet terminal 1008 includes a UI (User Interface) application 3801, a device control library 3802, a UDP / IP port (port is arbitrary) 3803, a WiFi (registered trademark) 3804, and a monitor discovery application. 3805, UDP / IP port (port is arbitrary) 3806, and WiFi (registered trademark) 3807. The numbers “3803” and “3806” in “UDP / IP port 3803” and “UDP / IP port 3806” are reference numerals and do not represent port numbers.

  The UI application 3801 is an application for displaying a UI on the display 4021 of the tablet terminal 1008. The device control library 3802 is a library used for controlling other communication devices such as the monitor 1001. The monitor discovery application 3805 is an application for the tablet terminal 1008 to discover the monitor 1001.

  The UDP / IP ports 3803 and 3806 are one of UDP / IP ports. The UDP / IP ports 3803 and 3806 convert data into UDP packets. UDP / IP ports 3803 and 3806 communicate with the broadband router 1002 using WiFi (registered trademark) 3804 and 3807, respectively. Specifically, the UDP / IP port 3803 uses WiFi (registered trademark) 3804 to perform communication based on the above ZigBee upper protocol. The UDP / IP port 3806 performs communication based on the monitor discovery protocol using WiFi (registered trademark) 3807.

  Here, a method for discovering the monitor 1001 using the monitor discovery application 3805 will be described as follows. First, the tablet terminal 1008 broadcasts a predetermined signal using a monitor discovery protocol. Based on the broadcast, the tablet terminal 1008 receives a response from a monitor in the same LAN (Local Area Network) segment. The tablet terminal 1008 acquires the IP address included in the response (that is, the IP address of the monitor that made the response). Thereby, the tablet terminal 1008 can find the monitor 1001. The tablet terminal 1008 sets the device control library 3802 for the IP address.

<F. Modification of network configuration>
(F1. First modification)
Next, an alternative configuration of the monitor 1001 will be described. FIG. 9 is a diagram illustrating a schematic configuration of a network when a tablet terminal is used as a control device of the network Z. Specifically, FIG. 9 is a diagram illustrating a configuration of a network Z using the tablet terminal 1009 instead of the monitor 1001, the personal computer 1003, and the tablet terminal 1008.

  Referring to FIG. 9, network Z includes tablet terminal 1009, broadband router 1002, a plurality of taps 1004a, 1004b, 1004c, and a plurality of home appliances (air conditioner 1005, refrigerator 1006, television 1007, etc.). Prepare. The tablet terminal 1009, the plurality of taps 1004, and the plurality of home appliances 1005 to 1007 constitute a low-speed wireless communication network Z. The tablet terminal 1009 is connected to the broadband router 1002 by high-speed wireless communication such as WiFi (registered trademark).

  FIG. 10 is a block diagram of the tablet terminal 1009. The tablet terminal 1009 includes a control unit 1901, an operation unit 1902, a display unit 1903, a high-speed communication interface unit 1904, a power supply unit 1905, a low-speed wireless communication module 1906, and an antenna 1907.

  The operation unit 1902 is an input device such as an operation key or a touch sensor. The display unit 1903 is an output device such as a liquid crystal display. The high-speed communication interface unit 1904 is an interface for performing wireless communication with the broadband router 1002. The power supply unit 1905 supplies power to the control unit 1901 and the low-speed wireless communication module 1906.

  The control unit 1901 is connected to the operation unit 1902, the display unit 1903, the high-speed communication interface unit 1904, the power supply unit 1905, and the low-speed wireless communication module 1906. A control unit 1901 controls the overall operation of the tablet terminal 1009. The control unit 1901 receives an input from the operation unit 1902. In addition, the control unit 1901 issues an output instruction to the display unit 1903.

More specifically, the control unit 1901 includes a CPU, a RAM, a ROM, a UART, and a GPIO. RAM, ROM, UART, and GPIO are each CP
Connected to U.

The low speed wireless communication module 1906 is connected to the antenna 1107. The low-speed wireless communication module 1906 controls communication with the power consumption measuring device in the low-speed wireless communication network Z. The low-speed wireless communication module 1906 includes a CPU, RAM, ROM, UART, GPIO, and a wireless RF (Radio Frequency) unit. RAM and R
The OM, UART, and GPIO are each connected to the CPU.

  Since the tablet terminal 1009 has the above-described configuration, the same effect as that of the configuration using the monitor 1001, the personal computer 1003, and the tablet terminal 1008 can be obtained.

(F2. Second modification)
In the above description, ZigBee (registered trademark) has been described as an example of the personal area network, but the personal area network is not limited to this. As a personal area network, the present invention can also be applied to other communication systems that support multi-hop.

<G. Functional Configuration of Wireless RF Built-in Communication Controller 1106>
FIG. 11 is a diagram illustrating a functional configuration of the wireless RF built-in communication controller unit 1106 of the monitor 1001. Referring to FIG. 11, wireless RF built-in communication controller unit 1106 includes a communication unit 11061, an acquisition unit 11062, a setting unit 11063, a specifying unit 11064, and an instruction unit 11065.

  The communication unit 11061 functions for the monitor 1001 to communicate with other devices such as the tap 1004, and is realized by the wireless RF unit 1165, for example.

  The acquisition unit 11062 is realized by acquiring a communication state between nodes (such as the tap 1004) in the wireless communication system, and the CPU 1161 executes a predetermined program, for example.

  The setting unit 11063 is realized by grouping two or more nodes (such as the tap 1004) constituting the wireless communication system, and for example, the CPU 1161 executes a predetermined program.

  Based on the communication strength of each node acquired by the acquisition unit 11062, the specification unit 11064 specifies a node whose communication strength is lower than a predetermined strength among nodes (such as the tap 1004) configuring the wireless communication system. This is realized by the CPU 1161 executing a predetermined program.

  The instruction unit 11065 generates an instruction to reconstruct the network or the like for the node of the group to which the node specified by the specifying unit 11064 belongs, and outputs the instruction to each node via the communication unit 11061. For example, the CPU 1161 This is realized by executing a predetermined program.

<H. Functional configuration of low-speed wireless communication module 2120>
FIG. 12 is a diagram illustrating a functional configuration of the low-speed wireless communication module 2120 of the tap 1004. Referring to FIG. 12, low-speed wireless communication module 2120 includes a communication unit 21201, a participation request unit 21202, a function switching unit 21203, and an information processing unit 21204.

  The communication unit 21201 functions for the tap 1004 to communicate with other nodes in the network Z (see FIG. 1), and is realized by the wireless RF unit 2125, for example.

  In the first embodiment, as described above, the communication unit 21201 can function as either an end device or a router in the network Z. For this reason, when ZigBee (registered trademark) is adopted as a communication method in the network Z, a physical device that implements the communication unit 21201 has an FFD (Full-Function) having full functions in accordance with the IEEE 802.15.4 standard. Device).

  The participation request unit 21202 is realized by transmitting a request to participate in the network Z to the coordinator of the network Z via the communication unit 21201, and for example, the CPU 2121 executes a predetermined program.

  The function switching unit 21203 switches the function of the communication unit 21201 between the router and the end device. In this specification, the function (router or end device) of the communication unit 21201 in the low-speed wireless communication module 2120 may be referred to as the function of the tap 1004 in the network Z.

  The information processing unit 21204 executes processing such as lighting of the LED 2105 based on information transmitted from another node, and also transmits information output from the power sensor unit 2110 to another node via the communication unit 21201. Send. The information processing unit 21204 is realized by, for example, the CPU 2121 and the GPIO 2124 that execute a predetermined program.

<I. Grouping in wireless communication systems>
As described above, in the first embodiment, the coordinator of the network divides the nodes constituting the radio communication system into groups, and instructs the reconfiguration of the network in units of groups. Hereinafter, grouping in the wireless communication system will be described.

FIG. 13 is a diagram schematically illustrating an example of a node group constituting the wireless communication system.
The wireless communication system shown in FIG. 13 includes 12 nodes. The twelve nodes include one monitor 1001 and eleven taps 1004 (tap 1004-1 to 1004-11). In FIG. 13, communication between nodes is indicated by a line written between the nodes. In FIG. 13, the character string shown in each node means the function of each node. More specifically, “Co” means a coordinator. “Ro” means a router. “Ed” means an end device.

  In the wireless communication system of FIG. 13, the monitor 1001 functions as a coordinator. The taps 1004-3, 1004-6, 1004-9 function as routers. The taps 1004-1, 1004-2, 1004-4, 1004-5, 1004-7, 1004-8, 1004-10, and 1004-11 function as end devices. The taps 1004-1 to 1004-6 communicate directly with the monitor 1001. The tap 1004-7 communicates with the monitor 1001 via the tap 1004-6. The taps 1004-8 and 1004-9 communicate with the monitor 1001 via the tap 1004-3. The taps 1004-10 and 1004-11 communicate with the monitor 1001 via the taps 1004-9 and 1004-3.

  The setting unit 11063 of the monitor 1001 sets a group for each relay node with respect to the nodes constituting the wireless communication system. The group includes a relay node and a node that directly communicates with the relay node. Here, the relay node is a node having a function of transferring data to another node, and is realized by, for example, a coordinator or a router.

  More specifically, in grouping, the coordinator first sets the first group for the own device and nodes that communicate directly with the own device. In the first group, the coordinator is a relay node. In the following description, the coordinator in each group or the relay node closest to the coordinator on the communication path is also referred to as “leader” as appropriate.

  Next, the coordinator sets a group whose leader is a node functioning as a router among the nodes of the first group. Next, the coordinator sets groups in which the router that does not communicate directly with the coordinator is a leader, in order from the coordinator. When the coordinator sets groups in the above order, a node functioning as a leader in the already set group is not added to the new group.

  FIG. 14 is a diagram illustrating an example of grouping by the setting unit 11063 for the wireless communication system illustrated in FIG. The contents of grouping for the wireless communication system will be described with reference to FIG. In FIG. 14, groups A to D are shown.

  Group A includes a monitor 1001 and taps 1004-1 to 1004-6 that directly communicate with the monitor 1001. In group A, a monitor 1001 that is a coordinator of the wireless communication system is a leader.

  Group B includes a tap 1004-6 and a tap 1004-7 that directly communicates with the tap 1004-6. In group B, a tap 1004-6 functioning as a router is a leader. When the groups are set in the above order, the node functioning as the leader in the already set group is not added to the new group. According to the above order, before the group B is set, the group A having the monitor 1001 as a coordinator as a leader is set. Accordingly, the monitor 1001 communicates directly with the tap 1004-6, but is not included in group B.

  Group C includes a tap 1004-3 and taps 1004-8 and 1004-9 that directly communicate with the tap 1004-3. In group C, a tap 1004-3 functioning as a router is a leader.

  Group D includes a tap 1004-3 and taps 1004-10 and 1004-11 that directly communicate with the tap 1004-9. In group D, a tap 1004-9 functioning as a router is a leader. According to the above order, before the group D is set, the group C with the tap 1004-3 serving as a router as the leader is set. Thus, tap 1004-3 communicates directly with tap 1004-9, but is not included in group D.

  The setting unit 11063 of the monitor 1001 performs grouping as shown in FIG. 14, and then stores the result in the RAM 1163 or the like.

<J. Overview of network reconstruction process>
In the wireless communication system according to the first embodiment, network reconfiguration is instructed for each group described above. Hereinafter, an overview of network reconstruction in the first embodiment will be described with reference to FIGS. 15 to 17. 15 to 17 are diagrams for explaining an overview of the network restructuring process in the first embodiment.

  FIG. 15 shows a state where the monitor 1001 has moved from the state shown in FIG. In FIG. 15, the width of the line connecting the nodes indicates the radio wave intensity in communication between the nodes. The thicker the line, the higher the radio wave intensity of communication.

  As the monitor 1001 moves as shown in FIG. 15, the distance between the monitor 1001 and each of the taps 1004-1 and 1004-4 to 1004-6 is larger than the distance between the nodes shown in FIG. 14. It is getting longer. Thereby, the radio field intensity in communication between the monitor 1001 and each of the taps 1004-1 and 1004-4 to 1004-6 is lowered, and the radio field intensity in communication between the tap 1004-6 and the tap 1004-7. Is low. In particular, the radio wave intensity at the taps 1004-1, 1004-5 to 1004-7 is low enough to hinder communication.

  The monitor 1001 continuously acquires the communication strengths of the taps 1004-1 to 1004-11 constituting the wireless communication system, for example, at regular intervals. When the monitor 1001 detects that the radio wave intensity of the communication of the taps 1004-1, 1004-5 to 1004-7 has become low, the monitor 1001 assigns the node of the group to which the taps 1004-1, 1004-5 to 1004-7 belong. Instruct the network to be reconfigured. In the example of FIG. 15, taps 1004-1, 1004-5, and 1004-6 belong to group A, and taps 1004-6 and 1004-7 belong to group B. Accordingly, the monitor 1001 instructs the nodes belonging to the group A and the group B to rebuild the network.

  However, even if the monitor 1001 moves as shown in FIG. 15, the radio field intensity of the nodes of the groups (groups C and D) other than the groups A and B does not decrease. Therefore, the monitor 1001 does not rebuild the network for the nodes in groups C and D.

  In the network restructuring instruction, the monitor 1001 first instructs all nodes in the target group to function as a router. In the example of FIG. 15, the monitor 1001 instructs all nodes in group A and group B to function as routers. In response to this, all nodes of group A and group B function as routers as shown in FIG. Thereafter, the networks are reconstructed in group A and group B. Thereby, the connection mode between the nodes in the group A is changed. The change of the connection mode is indicated by the fact that the mode of the line connecting the nodes shown in FIG. 16 is changed from the mode of the line connecting the nodes shown in FIG.

  After the reconstruction, each group leader instructs a node that does not need to function as a router to change the function of the node to an end device. More specifically, the monitor 1001 causes the end device to change the function of the node (tap 1004-1) located at the end of the network communication. The tap 1004-6 causes the end device to change the function of the node (tap 1004-7) located at the end of the network communication. As a result, as shown in FIG. 17, the functions of the taps 1004-1 and 1004-7 are switched to the end device (Ed).

<K. Network reconstruction process flow>
Next, the flow of the network reconstruction process described with reference to FIGS. 15 to 17 will be described. FIG. 18 is a flowchart of the network restructuring process shown in FIGS.

  Referring to FIG. 18, when the construction of the network is completed, the coordinator (wireless RF built-in communication controller unit 1106 of monitor 1001) acquires the radio wave intensity of network communication of each node of groups A to D in steps S <b> 1 to S <b> 4. To do. If the radio field intensity of at least one group of nodes is equal to or lower than a preset threshold value (the radio field intensity of at least one node is weak), the process proceeds to step S5. On the other hand, if the radio field strength of all the group nodes exceeds the threshold value (all nodes can communicate with each other with sufficient radio field intensity), the coordinator continues the processing of steps S1 to S4.

  In step S5, the leader of the group whose radio field intensity of the node to which it belongs becomes equal to or less than the above threshold value requests the coordinator to join the network in a new state. In the example of FIG. 18, among the groups A to D, the leader of the group B outputs the request to the coordinator in step S5. In response to this, the coordinator instructs the leader of the group to reconfigure the network in the group. In response, in step S6, the reader changes its own state from the “normal state” to the “reset state”.

  As shown in step S8, each node of each group acquires the status of the leader of the group to which the node belongs at regular intervals. When it is detected that the state of the leader of the group to which the own device belongs is “reconstructed”, each node outputs a request for participation in the network to the coordinator in step S9. The coordinator reconfigures a communication network in the network in the group in response to a network participation request from each node. At the time of reconstruction, all the nodes in the group temporarily function as routers based on instructions from the coordinator. As a result, as described with reference to FIGS. 15 and 16, the network in the group is reconstructed.

  When the reconstruction is completed, in step S10, new leaders of the group in which the network has been reconstructed (the leader may not be changed before and after the reconstruction) are transmitted to some slave units (leaders in the group). Change the function of the node other than More specifically, as described with reference to FIG. 17, the node located at the end of the network is instructed to change the function to the end device.

  In step S11, the reader changes the state of the own device from the “reset state” to the “normal state”.

  In the first embodiment described above, the groups constituting the wireless communication system are divided into groups centered on relay nodes. If a communication failure occurs due to movement of a node or the like, the network is reconstructed only for the group to which the failed node belongs. As a result, it is possible to avoid an unnecessary attempt to reconstruct a network for a node in a group that does not require restructuring because there is no problem.

[Second Embodiment]
<Overview of network reconstruction process>
In the second embodiment of the wireless communication system, the communication quality is maintained at a certain level or higher for the entire network or for each group set in the wireless communication system.

  In the second embodiment of the wireless communication system, the coordinator (wireless RF built-in communication controller unit 1106) has a failure in communication (impossible to communicate, or communication pattern (optimization list) of nodes constituting the wireless communication system and communication state. The node pattern (communication failure pattern) in which the radio wave intensity has become lower than the threshold value is associated with each other and stored in a nonvolatile storage device (not shown in FIG. 3). The optimization list is a pattern for specifying which node communicates with which node in the wireless communication system. The communication failure pattern is a pattern indicating which node in the wireless communication system has a communication failure. Then, in the wireless communication system, the coordinator obtains the pattern of the node where the communication failure actually occurred, and each node in the wireless communication system follows the pattern corresponding to the optimization list corresponding to the pattern. Control communication.

  The network reconstruction according to the second embodiment will be described more specifically with reference to FIG. FIG. 19 is a diagram for describing a mode of network reconstruction according to the second embodiment.

  FIG. 19A shows an example of a connection mode between nodes in a wireless communication system at a certain point in time. The wireless communication system shown in FIG. 19A corresponds to a wireless communication system shown in FIG. 14 with a tap 1004-12 added. The tap 1004-12 communicates with the monitor 1001 via the tap 1004-6 and belongs to the group B.

  In the wireless communication system as shown in FIG. 19A, it is assumed that the communication strength at taps 1004-2 to 1004-5 is reduced due to the occurrence of an obstacle or the like. At this time, the monitor 1001, which is a coordinator, periodically detects the communication strength of each node in the wireless communication system, thereby detecting that a failure has occurred in communication at the taps 1004-2 to 1004-5.

  In response to this, the monitor 1001 refers to the communication failure pattern stored in the own device, and searches for a pattern indicating that a failure occurs in the tap 1004-2 to the tap 1004-5. If the pattern is stored, the monitor 1001 acquires an optimization list stored in association with the pattern. Then, the monitor 1001 reconstructs the network in the wireless communication system in order to control the connection mode between the nodes according to the acquired optimization list.

  FIG. 19B is a diagram illustrating an example of the result of the reconstruction. In the connection mode shown in FIG. 19B, the connection partner of the tap 1004-2 is changed from the monitor 1001 to the tap 1004-1 as compared to the connection mode shown in FIG. Has been. The connection partner of the tap 1004-3 is changed from the monitor 1001 to the tap 1004-2. The connection partner of the tap 1004-4 is changed from the monitor 1001 to the tap 1004-5. The connection partner of the tap 1004-5 is changed from the monitor 1001 to the tap 1004-6. The functions of the taps 1004-1, 1004-2, and 1004-5 are changed from the end device to the router.

<Functional Configuration of Wireless RF Built-in Communication Controller 1106>
With reference to FIG. 20, a functional configuration of the wireless RF built-in communication controller unit 1106 of the monitor 1001 according to the second embodiment will be described. FIG. 20 is a diagram illustrating a functional configuration of the wireless RF built-in communication controller unit 1106 according to the second embodiment.

  20, the configuration of the instruction unit 11065 is described in more detail than FIG. Referring to FIG. 20, instruction unit 11065 includes network optimization information storage unit 11065A, communication failure pattern storage unit 11065B, optimization list storage unit 11065C, security level storage unit 11065D, and instruction information generation unit 11065E. including.

  The network optimization information storage unit 11065A stores network optimization information. The network optimization information is information that specifies conditions for reconfiguring the network. The network optimization information storage unit 11065A is realized by, for example, a non-volatile storage device provided in the wireless RF built-in communication controller unit 1106 as described above. A specific example of the network optimization information will be described later with reference to FIGS. 21 and 22.

  The communication failure pattern storage unit 11065B stores the communication failure pattern described above, and is realized, for example, by the nonvolatile storage device of the wireless RF built-in communication controller unit 1106.

  The optimization list storage unit 11065C stores the above optimization list, and is realized, for example, by a nonvolatile storage device of the wireless RF built-in communication controller unit 1106.

  The security level storage unit 11065D stores information specifying the security level input to the monitor 1001, and is realized by the RAM 1163, for example.

  The instruction information generation unit 11065E acquires the communication state (communication radio wave intensity and the like) of each node in the wireless communication system, determines the mode of network reconfiguration based on the communication state, and sends the network to each node. Outputs instructions for realizing the reconstruction of. The instruction information generation unit 11065E is realized by the CPU 1161 and the wireless RF unit 1165, for example.

<Specific examples of network optimization information>
21 and 22 are diagrams schematically illustrating specific examples of the contents of the network optimization information in the second embodiment.

  First, referring to FIG. 21, the network optimization information includes “security level”, “item”, and “content”. “Security level” corresponds to the security level set in the monitor 1001.

  The “item” includes “execution condition”, “number of backup lists”, and “time until optimization execution”. The “execution condition” is a condition for executing network reconstruction. The “number of backup lists” is the number of patterns held as an optimization list. The “time until optimization execution” is the time from when the “execution condition” is satisfied until an instruction for restructuring the network is output.

“Content” is information for specifying the content of each item defined in “Item”.
In the network optimization information, the number of optimization lists stored in the network optimization information storage unit 11065A indicates under what conditions network reconstruction is started for each security level set in the monitor 1001. And information for specifying at which timing after the above condition is satisfied, each node of the wireless communication system outputs an instruction for reconstruction.

  In the monitor 1001, the security level can be set in three stages of “high”, “medium”, and “low”.

  As a specific example of network reconstruction according to the network optimization information, an example in which “high” is set as the security level will be described.

  Corresponding to the setting contents of the “execution condition”, processing for network reconstruction is started on the condition that one or more of the nodes constituting the wireless communication system have a communication failure. . “Problem” means, for example, that the radio wave intensity of communication at a node is below a predetermined threshold. In this case, corresponding to the number of backup lists being set to “50”, 50 optimization lists (connection patterns between nodes in the network) are stored in the optimization list storage unit 11065C. Corresponding to the fact that “time until optimization execution” is set to “10 seconds”, the instruction information generation unit 11065E reconstructs the network 10 seconds after determining that the above condition is satisfied. The instruction for is output to each node.

  More specifically, the instruction information generation unit 11065E identifies which node in the wireless communication system has a communication failure when the above condition is satisfied, and based on the specific result, the communication failure A communication failure pattern stored in the pattern storage unit 11065B is acquired that matches the current situation. Then, the instruction information generation unit 11065E acquires an optimization list stored in association with the acquired communication failure pattern from the optimization list storage unit 11065C. Then, the instruction information generation unit 11065E outputs an instruction to each node in the wireless communication system so that the nodes communicate in a connection manner according to the acquired optimization list.

  In the network optimization information of FIG. 21, the “execution condition” may be applied to each group instead of being applied to the entire network configured by the wireless communication system. Thereby, the instruction information generation unit 11065E determines whether or not the “execution condition” is established for each group based on the communication state of each node. For example, if the instruction information generation unit 11065E determines that a communication failure has occurred in one node in at least one group when the security level is set to “high”, the network is configured as described above. An instruction for reconstruction is output to each node.

FIG. 22 shows another specific example of the network optimization information.
The network optimization information shown in FIG. 22 includes “security level”, “item”, and “content” as in the case of FIG. In FIG. 22, the “execution condition” defines the number of times a timeout occurs due to a communication failure for each group. The instruction information generation unit 11065E determines, for each group, whether or not an “execution condition” is satisfied based on the communication state of each node. For example, when the security level is set to “medium”, the instruction information generation unit 11065E performs communication in at least one group after the network is constructed or the previous network is reconstructed. If it is determined that a timeout has occurred 5 times or more, an instruction for network reconstruction is output to each node as described above.

  Even when it is determined whether or not the “execution condition” is satisfied in the entire network as described with reference to FIG. 21, the “execution condition” is specified using the number of times the timeout has occurred. There may be cases.

<Network rebuilding process>
With reference to FIGS. 23 and 24, the network restructuring process in the second embodiment will be described more specifically. FIG. 23 and FIG. 24 are diagrams for explaining the contents of the network restructuring process in the second embodiment. Here, an example in which the “execution condition” is determined for each group will be described.

  The instruction information generation unit 11065E periodically detects the communication state of each node of the wireless communication system, and based on the detection result, the communication state of each group indicates the “execution condition” (see FIG. 21 or FIG. 22). ) Is determined. When the instruction information generation unit 11065E determines that the communication state of at least one group corresponds to the “execution condition”, the instruction information generation unit 11065E starts a process for rebuilding the network in the group.

  More specifically, the instruction information generation unit 11065E determines, for example, that the communication state of the node in group A corresponds to the “execution condition” as shown in step 1 in FIG. In FIG. 23, the nodes constituting each group correspond to the elements shown in FIG. 19A as shown in FIG.

  As illustrated in FIG. 19A, when a communication failure occurs in the taps 1004-2 to 1004-5, the instruction information generation unit 11065 E indicates that the instruction information It is determined whether the “execution condition” corresponding to the security level set by the generation unit 11065E is satisfied. Then, if it is determined that it corresponds, the instruction information generation unit 11065E has a pattern that matches the pattern of the node in which a communication failure has occurred (a pattern in which a communication failure has occurred in the taps 1004-2 to 1004-5). It is determined whether it is stored in communication failure pattern storage unit 11065B.

  If the instruction information generation unit 11065E determines that a pattern that matches the pattern of the node in which the communication failure has occurred is stored in the communication failure pattern storage unit 11065B, the process proceeds to step 2-1. On the other hand, if the instruction information generating unit 11065E determines that no matching pattern is stored, the instruction information generating unit 11065E proceeds to step 2-2 (see FIG. 24 described later).

  In step 2-1, the instruction information generation unit 11065E specifies a communication failure pattern that matches the pattern of the node in which the communication failure has occurred, and specifies an optimization list stored in association with the specified communication failure pattern. To do.

  In FIG. 23, communication failure patterns stored in the communication failure pattern storage unit 11065B are shown as patterns P1, P2, P3. The optimization lists stored in the optimization list storage unit 11065C are shown as lists L1, L2, L3. The pattern P1 is associated with the list L1. The patterns P2 and P3 are associated with the lists L2 and L3, respectively. In the example of FIG. 23, the instruction information generation unit 11065E specifies the pattern P3, and specifies the list L3 based on this.

  Then, the instruction information generation unit 11065E instructs each node on the communication mode so that each node of the wireless communication system communicates through the communication path described in the specified optimization list.

  Referring to FIG. 24, in step 2-2, the instruction information generation unit 11065E uses the network of the group (in the example of FIG. 23, group A) determined to satisfy the “execution condition” as the first embodiment. Rebuild as described with reference to. Then, the instruction information generation unit 11065E stores the pattern of the node having the communication failure acquired in Step 1 in the communication failure pattern storage unit 11065B as a new pattern (pattern PA in FIG. 24). The result of the reconstruction as described with reference to the embodiment is stored in the optimization list storage unit 11065C as a new optimization list (list LA in FIG. 24) in association with the pattern PA.

  When the number of optimization lists stored in the optimization list storage unit 11065C exceeds the number specified by the number of backup lists of network optimization information by newly storing the optimization list, the instruction information generation unit 11065E deletes the oldest created optimization list from the stored optimization lists and stores the newly generated optimization list in the optimization list storage unit 11065C. In addition, when the priority is assigned to the list stored in the optimization list storage unit 11065C, the instruction information generation unit 11065E deletes the one with the lower priority and creates a newly created optimization list. It may be stored.

[Modification]
In the first and second embodiments, the tap 1004 is cited as an example of a node. The node is not limited to a tap as long as it is a terminal having a communication function for connecting to a network. Examples of the device that realizes the node include various devices such as a smartphone, a mobile phone, a notebook computer, and a tablet terminal.

  It should be thought that embodiment disclosed this time and its modification are illustrations in all the points, and are not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims. It is intended that the techniques disclosed in the embodiments and the modifications thereof can be implemented alone or in combination as much as possible.

  1001 monitor, 1004, 1004-1 to 1004-12 tap, 1106 wireless RF built-in communication controller unit, 1161, 2121 CPU, 2120 low-speed wireless communication module, 11061, 2201 communication unit, 11062 acquisition unit, 11063 setting unit, 11064 specifying unit 11065 instruction unit 11065A network optimization information storage unit 11065B communication impossible pattern storage unit 11065C optimization list storage unit 11065D security level storage unit 11065E instruction information generation unit 21202 participation request unit 21203 function switching unit 21204 Information processing department.

Claims (5)

A management node for managing a wireless communication system composed of two or more nodes,
Setting means for setting, for each relay node that transfers data to other nodes in the wireless communication system, a group constituted by nodes that communicate directly with the relay node;
Obtaining means for obtaining communication strength at each node of the wireless communication system;
Among the nodes of the wireless communication system, a specifying unit that specifies a node in which the communication strength acquired by the acquiring unit is lower than a predetermined strength;
A management node comprising: an instruction unit that outputs an instruction to change a function to a relay node and reconstruct a network to a node of a specific group to which the node specified by the specifying unit belongs.   The management node according to claim 1, wherein the instruction unit does not output the instruction to a node that functions as a relay node in a group different from the specific group among nodes belonging to the specific group. A program executed by a computer of a management node that manages a wireless communication system including two or more nodes,
The program is stored in the computer.
For each relay node that transfers data to other nodes in the wireless communication system, setting a group composed of nodes that communicate directly with the relay node;
Obtaining communication strength at each node of the wireless communication system;
Identifying a node whose acquired communication strength is below a predetermined strength among nodes of the wireless communication system;
A program for causing a node of a specific group to which a node having a communication strength lower than a predetermined strength belongs to output an instruction to change a function to a relay node and reconstruct a network. A wireless communication system composed of two or more nodes,
The two or more nodes include a management node that manages the wireless communication system,
The management node is
Setting means for setting, for each relay node that transfers data to other nodes in the wireless communication system, a group constituted by nodes that communicate directly with the relay node;
Obtaining means for obtaining communication strength at each node of the wireless communication system;
Among the nodes of the wireless communication system, a specifying unit that specifies a node in which the communication strength acquired by the acquiring unit is lower than a predetermined strength;
A wireless communication system, comprising: instruction means for outputting an instruction to change a function to a relay node and reconstruct a network to a node of a specific group to which the node specified by the specifying means belongs.   The wireless communication system according to claim 4, wherein after the reconfiguration, the relay node outputs an instruction to function as an end node to a node that has become a terminal by the reconfiguration.

Images