JP6604243B2 - Short-range wireless communication mesh network system, short-range wireless communication method, and short-range wireless communication program - Google Patents

Description

  The present invention relates to a mesh network system for near field communication, a near field communication method, and a near field communication program.

  In recent years, in order to realize an information society that can receive optimal services under various environments, for example, Japanese Patent Application Laid-Open No. 2014-182707 “Sensor Network System, Expert Determination Method and Program” As described in Japanese Patent Application Laid-Open No. 2014-068285, “Sensor Data Collection System and Gateway Control Method” of Patent Document 2, the construction of a sensor network including minute sensor nodes has been studied earnestly. That is, a sensor network that forms IoT (Internet of Things) that uses the Internet for a wider range of applications, or forms an M2M (Machine to Machine) that connects machines via a network. The research of is becoming active. As this type of sensor network, for example, a sensor is attached to a public building and information on the strength of the public building is transmitted via the Internet to constantly monitor the strength, or to the athlete's foot. There are some that are not related to the network until now, such as attaching a sensor and measuring the fatigue level, behavior pattern, etc. of the athlete to develop tactics.

  In such a sensor network such as IoT and M2M, a sensor device that obtains target information is equipped with a wireless device that enables short-range wireless communication, so that the Internet can be connected via a gateway or the like. The acquired information is transferred to a wide area network.

  In general, an IP address or a MAC address (Media Access Control Address) used in an IP (Internet Protocol) network is used as an identifier for identifying a transmission source and a transmission destination in wireless communication of a sensor node, and sensor information is transmitted and received. As a communication medium, a sensor packet having a frame configuration close to existing IP or MAC is used.

  In a sensor network for short-range wireless communication, sensor information can be acquired even remotely, and a variety of various services can be provided. Expenses required for infrastructure construction and maintenance are enormous. Also, since services that support social infrastructure including meter reading of gas, water supply, electricity, etc., strength measurement of bridges and schools, etc. are naturally targeted, disruption of the sensor network is not allowed. Therefore, it is desired to use a mesh network that is resistant to disaster and easy to install as a sensor network.

  Furthermore, the construction of a mesh network for short-range wireless communication that can reliably transmit and receive a wider range of information is strongly desired, as well as a sensor network that transmits and receives sensor information. The mesh network is disclosed in, for example, the re-specialized WO2012 / 131853 “Management Server and Gateway” of Patent Document 3. Japanese Patent Laid-Open No. 2013-232963 “Wireless Node Device” in Patent Document 4 discloses an ad hoc network which is a kind of mesh network.

JP 2014-182707 A JP 2014-068285 A International Publication No. 2012/131853 JP 2013-232963 A

  However, in the case of the transmission method using the mesh network (Patent Documents 3 and 4) as described above as the sensor network (Patent Documents 1 and 2), every time a wireless communication request is generated, the route from the transmission source to the transmission destination Since the data (sensor information) is transmitted again, compared to the transmission processing amount of the data (sensor information) to be transmitted, the selection of the route for the preparation requires more radio resources (for route selection). Multiple communication) and time. As the number of sensor nodes connected to the sensor network increases, the load due to route selection increases, and there is a high possibility that wireless communication related to essential sensor information cannot be performed due to the occurrence of an overload state.

  In addition, every time a wireless communication request is generated, it is not possible to easily grasp the current state of the mesh network in order to reselect the communication path. Specifically, even if wireless communication related to essential sensor information cannot be performed at present, for example, whether wireless communication is too crowded (saturated) and communication is not possible. Or it cannot be distinguished whether it is in the state which cannot communicate because an important communication node on a path | route failed. Such a problem is not limited to only the sensor network, but is strongly desired to be solved in all the short-distance wireless communication mesh networks that perform short-distance mesh wireless communication.

(Object of the present invention)
The present invention has been made in view of such a problem, and is a short-range wireless communication mesh network system that reduces the load of route selection and enables efficient communication in a mesh network that performs short-range mesh wireless communication. An object of the present invention is to provide a short-range wireless communication method and a short-range wireless communication program.

  In order to solve the above-described problem, the mesh network system for short-range wireless communication, the short-range wireless communication method, and the short-range wireless communication program according to the present invention mainly adopt the following characteristic configuration.

(1) A mesh network system for near field communication according to the present invention includes a plurality of communication nodes and a gateway having a network management function, and mesh wireless between the communication nodes or between the communication nodes and the gateway. A mesh network system for near field communication that performs communication,
The gateway has two network operation modes, ie, a mesh network construction operation mode and a network service provision operation mode, as the network management function. In the mesh network construction operation mode, By collecting information about surrounding communication nodes capable of wireless communication with the communication nodes, creating network information about the respective layers and routes of each of the communication nodes, by a pseudo unicast communication method, After notifying each of the communication nodes capable of wireless communication of the network information regarding the corresponding hierarchy and route, and building a mesh network, wireless communication is possible by a pseudo broadcast communication method. All the communication nodes Against de notifies an instruction to start the network services, is shifted from the mesh network construction mode of operation to the network service provider operating mode,
On the other hand, each of the communication nodes stores the network information notified from the gateway by the pseudo unicast communication method in the mesh network construction operation mode, and the network by the pseudo broadcast communication method from the gateway. After receiving an instruction to start a service and shifting to the network service providing operation mode, the data transmission / reception operation is performed according to the stored network information when data transmission / reception is performed.

(2) A short-range wireless communication method according to the present invention includes a plurality of communication nodes and a gateway having a network management function, and performs mesh wireless communication between the communication nodes or between the communication node and the gateway. A short-range wireless communication method in a mesh network system for short-range wireless communication,
The gateway has two network operation modes, ie, a mesh network construction operation mode and a network service provision operation mode, as the network management function. In the mesh network construction operation mode, By collecting information about surrounding communication nodes capable of wireless communication with the communication node, creating network information about the hierarchy and route of each of the communication nodes, by a pseudo unicast communication method, After notifying each of the communication nodes capable of wireless communication of the network information regarding the corresponding hierarchy and route, and building a mesh network, wireless communication is possible by a pseudo broadcast communication method. All the communication nodes Against de notifies an instruction to start the network services, is shifted from the mesh network construction mode of operation to the network service provider operating mode,
Meanwhile, each of the communication nodes stores the network information notified to each of the gateways by the pseudo unicast communication method in the mesh network construction operation mode, and the network is transmitted from the gateways by the pseudo broadcast communication method. After receiving an instruction to start a service and shifting to the network service providing operation mode, the data transmission / reception operation is performed according to the stored network information when data transmission / reception is performed.

  (3) A short-range wireless communication method program according to the present invention is characterized in that the short-range wireless communication method described in (2) is implemented as a program executable by a computer.

  According to the mesh network system for near field communication, the near field communication method, and the near field communication program of the present invention, the following effects can be obtained.

  In the present invention, the amount of communication for determining a route for data transmission / reception can be greatly reduced as compared with a mesh network system for short-range wireless communication in the prior art.

  In other words, in the prior art, when data is transmitted to a node, for example, a gateway, to which a specific communication node is a destination, an inquiry about whether a final destination node, for example, a gateway is found is made to surrounding communication nodes. I do. The neighboring communication nodes that have received the inquiry further repeat the operation of making the same inquiry to the neighboring communication nodes until a final destination node, for example, a gateway is found. As a result, for example, with respect to each communication node, on average, three peripheral communication nodes are visible, and a node, for example, a gateway, four layers ahead from a specific communication node to transmit data is the destination In this case, 3 ^ 4 = 81 transmission operations are required at least before the data transmission path is determined.

  On the other hand, in the present invention, since the network information related to the hierarchy (rank) and route of each communication node is determined in advance and set in advance in each communication node, for example, communication in the fourth hierarchy Even when data is transmitted from the node to the 0th layer node, for example, the gateway, which is four layers ahead, only the data transmission operation is performed four times based on the preset route information. Thus, the transmission operation can be completed.

It is a network block diagram which shows the network structural example of the mesh network system for near field communication based on this invention. It is explanatory drawing for demonstrating an example of the adjacency matrix regarding the communication node which can be wirelessly created as one step of the 2nd procedure in the mesh network construction operation mode of the mesh network system for near field communication which concerns on this invention. . FIG. 3 is an explanatory diagram illustrating a power calculation result of the adjacency matrix illustrated in FIG. 2. It is explanatory drawing which shows the calculation result of the power of the adjacency matrix A (namely, adjacency matrix A ^ 2). It is explanatory drawing which shows the calculation result of the power of 3 of adjacency matrix A (namely, adjacency matrix A ^ 3). It is explanatory drawing which shows the calculation result of the power of 4 of adjacency matrix A (namely, adjacency matrix A ^ 4). It is explanatory drawing which shows the calculation result of 5 to the power of adjacency matrix A (namely, adjacency matrix A ^ 5). It is explanatory drawing which shows the calculation result of the power of 6 of adjacency matrix A (namely, adjacency matrix A ^ 6). Explanatory drawing for demonstrating an example of the procedure which determines the hierarchy (rank) and path | route of each communication node as a 2nd procedure in the mesh network construction operation mode of the mesh network system for near field communication which concerns on this invention ( In FIG. 4 (B)), it is a figure which shows the communication node i which is confirmed (decided) as the candidate of the communication node i ranked in each of ranks 1-4, or ranking to each. It is explanatory drawing for demonstrating an example of the procedure which determines the hierarchy (rank) and path | route of each communication node as a 2nd procedure in the mesh network construction operation mode of the mesh network system for near field communication which concerns on this invention. is there. In the explanatory diagram of FIG. 4B showing an example of a procedure for determining the hierarchy (rank) and route of each communication node as the second procedure, the route of the communication node i of each rank of ranks 1 to 4 is determined ( It is a figure which shows the procedure to determine. As a third procedure in the mesh network construction operation mode of the mesh network system for short-range wireless communication according to the present invention, network information related to the hierarchy (rank) and route of each communication node is notified to each corresponding communication node. It is explanatory drawing for demonstrating an example of a procedure. An example of a procedure for notifying all communication nodes of information indicating that a service for the entire network is started as a fourth procedure in the mesh network construction operation mode of the mesh network system for short-range wireless communication according to the present invention will be described. It is explanatory drawing for doing. It is explanatory drawing for demonstrating an example of the procedure in the normal measurement operation mode of the mesh network system for near field communication which concerns on this invention as a 5th procedure. FIG. 2 is a network configuration diagram showing a network configuration example different from that of FIG. 1 of the mesh network system for short-range wireless communication according to the present invention.

  Preferred embodiments of a mesh network system for short-range wireless communication, a short-range wireless communication method, and a short-range wireless communication program according to the present invention will be described below with reference to the accompanying drawings. In the following description, a mesh network system for short-range wireless communication and a short-range wireless communication method according to the present invention will be described. The short-range wireless communication method is implemented as a short-range wireless communication program that can be executed by a computer. Needless to say, the short-range wireless communication program may be recorded on a computer-readable recording medium. In addition, it is needless to say that the drawing reference numerals attached to the following drawings are added for convenience to the respective elements as an example for facilitating understanding, and are not intended to limit the present invention to the illustrated embodiments. Yes.

(Features of the present invention)
Prior to the description of the embodiments of the present invention, an outline of the features of the present invention will be described first. The present invention creates and manages path information related to a mesh network for short-range wireless communication by a gateway (GW) or a server on the cloud, and sets the transfer destination of transmission data in each communication node (for example, a sensor node). By controlling according to the route information, it is possible to grasp the failure state and traffic state on the mesh network even on the low-function communication node (for example, sensor node) side, so that wireless communication can be performed efficiently. The main feature is to do.

  More specifically, the present invention provides two network operation modes: a mesh network construction operation mode and a network service providing operation mode (for example, a normal measurement operation mode in the case of a sensor network). In the mesh network construction operation mode, a gateway or a server on the cloud acquires a list of adjacent communication nodes that can communicate from each communication node, and based on the acquired list, a mesh network capable of wireless communication is obtained. The network information about the role (hierarchy (rank)) and route information of the corresponding communication node is notified to each communication node by pseudo unicast communication, and all communication nodes are notified by pseudo broadcast communication. Is instructed to start a network service, and shifts to a network service providing operation mode (for example, a normal measurement operation mode in the case of a sensor network).

  On the other hand, in a network service providing operation mode (for example, a normal measurement operation mode in the case of a sensor network), each communication node transmits transmission data (for example, to a transmission destination) according to route information notified from the server side on the gateway or cloud. When the communication node is a sensor node, the measurement data measured by the sensor node is transmitted. Also, the server side on the gateway or cloud monitors the transmission data from each communication node, and if the transmission data (measurement data) is not notified within a predetermined time, the network operation is abnormal. And instructing all communication nodes to stop providing the network service (for example, in the case of a sensor network, stop the sensor information measurement operation) by pseudo broadcast communication. And rebuild the mesh network.

(Embodiment of the present invention)
Next, an embodiment of a mesh network system for short-range wireless communication according to the present invention will be described in detail with reference to the drawings. This mesh network system for short-range wireless communication includes at least an input / output device that inputs and outputs data (in the case of a sensor node, a sensor that measures and acquires target information) and a wireless device that performs wireless communication. A gateway having at least a function of constructing a mesh network that wirelessly connects each communication node and managing path information of each communication node as a network management function with a plurality of communication nodes (for example, a sensor node in the case of a sensor network) (Gateway: GW). Note that the network management function for constructing a mesh network and managing the routing information of each communication node may be provided on the server side on the cloud to which the gateway is connected instead of the gateway. The case where the gateway is provided will be described.

  When a gateway (or a server on the cloud) is set to a mesh network construction operation mode for constructing a mesh network, a list including communication nodes visible from the gateway and peripheral communication nodes visible from each communication node (White List: WL) is created and held, the hierarchy and route of each communication node is determined from the list (that is, the network is determined), and information regarding the determined network is notified to each communication node. Thereafter, the start of the network service is notified to each communication node, the data transmission / reception operation in each communication node is started, and the mode is shifted from the mesh network construction operation mode to the network service provision operation mode. In the following, a procedure for constructing a mesh network according to the current environmental situation and for each communication node to transmit and receive data will be described in detail step by step.

(First Procedure): Creation of a List of Adjacent Communication Nodes Visible from Each Communication Node (Sensor Node) First, in the gateway, a WL list for registering MAC addresses of communication nodes (sensor nodes) in a state where wireless communication is possible ( An example of the procedure for creating (White List: WL) will be described with reference to the network configuration diagram of FIG. FIG. 1 is a network configuration diagram illustrating a network configuration example of a mesh network system for short-range wireless communication according to the present invention. FIG. 1 is a diagram illustrating a mesh network construction operation mode of a mesh network system for short-range wireless communication according to the present invention. It is also an explanatory diagram used to explain an example of a procedure for collecting information on communication nodes capable of wireless communication as one procedure. In the following, referring to FIG. 1, in the highest gateway 1, the MAC addresses of all communication nodes i capable of wireless communication (sensor nodes i: i = 2, 3,..., 16) are acquired. An example of a procedure for creating a registration list for registering communicable communication nodes, that is, a WL list (White List: WL) will be described.

  In FIG. 1, the gateway 1 acquires the MAC address of each communication node i (i = 2, 3, 4,...) And registers a communication node in a state where wireless communication is possible, that is, a WL list ( Although an example of a procedure for creating a (White List) is shown, such an operation may be performed in the server 20 on the cloud that can communicate with the gateway 1 instead of the gateway 1. In the example shown in FIG. 1, a total of 15 communication nodes i (i = 2,..., 16) are shown. However, the number of communication nodes i is not limited to such a number. There is no problem with any number.

  In the explanatory diagram of FIG. 1, first, when the gateway 1 is powered on, an advertisement packet including its own MAC address is sent to the neighboring communication node i (in the case of FIG. 1) in order to notify the neighboring communication node i of its existence. Is transmitted to the communication node 2, 3 and 4 in the vicinity (step S1). Similarly, each communication node i, when the power is turned on, sends an advertisement packet including its own MAC address to neighboring communication nodes i and gateways 1 in order to notify the neighboring communication nodes i and gateways 1 of their existence. (Step S2). The gateway 1 receives the advertisement packet from the peripheral communication node i, creates and stores a WL list (White List: WL) in which the MAC addresses of the peripheral communication nodes i capable of wireless communication are registered (step S3). .

  Furthermore, the gateway 1 searches for the communication node i existing in the vicinity, and stores the one that matches the communication node i whose MAC address is registered in the WL list (step S4). Thereafter, the gateway 1 notifies the searched communication node i of the WL list (step S5).

  Each communication node i that has received the notification of the WL list from the gateway 1 searches for the communication node i existing in the vicinity, and the MAC address is included in the WL list created based on the reception result of the advertised packet from the peripheral communication node i. The WL list of the communication node i is updated only for those that match the registered communication node i, the updated WL list is notified to the gateway 1 (step S6), and the detected peripheral communication nodes The updated WL list is notified to i (step S7).

  Further, each communication node i that has received the notification of the WL list from the peripheral communication node i searches for the communication node i existing in the vicinity, and updates and updates the WL list of the communication node i by the same procedure. The WL list is notified to the communication node i that has notified the WL list, and sequentially notified to the gateway 1 via each communication node i that has received the notification of the WL list, and the detected peripheral The operation of notifying the communication node i of the updated WL list is repeated (step S8). When the gateway 1 determines that it has reached the stage where it has received the WL list from all the communication nodes i in a state capable of wireless communication, the gateway 1 ends the WL list creation / collection operation (step S9).

(Second procedure): Determination of hierarchy (rank) and route of each communication node from the WL list (that is, determination of mesh network)
Next, the gateway 1 that has completed the creation of the WL list determines the hierarchy (rank) of each communication node i and determines the route, with an example of each operation illustrated in FIG. 2, FIG. 3, and FIG. This will be sequentially described with reference to the drawings. First, FIG. 2 illustrates an example of an adjacency matrix relating to communication nodes capable of wireless communication created as one step of the second procedure in the mesh network construction operation mode of the mesh network system for short-range wireless communication according to the present invention. FIG. 2 is an explanatory diagram for explaining an example of an adjacency matrix created in order to determine the configuration of a mesh network in which each communication node performs short-range wireless communication. The network configuration diagram on the left side of FIG. 2 is a reproduction of the network configuration diagram shown in FIG.

In addition to the WL list created by the gateway 1 itself, the gateway 1 also holds WL lists acquired from all communication nodes i (i = 2, 3, 4,..., 16). The gateway 1 uses the WL list created by itself and the WL list acquired from each communication node i as a vector, and combines them, as shown in the matrix on the right side of FIG. A matrix representing which communication node j is visible,
Adjacency matrix A = (a _{i, j} )
a _{i, j} : Indicates whether sensor node j is visible from sensor node i.
(A _{i, j} = 1: visible, a _{i, j} = 0: invisible)
Create as.

For example, in the network configuration diagram on the left side of FIG. 2, only three communication nodes 2, 3, and 4 are visible from the gateway 1 as communication nodes j capable of direct wireless communication, and other communication nodes j are visible. The elements a _{1 and j in} the first row of the adjacency matrix A are as follows. Assume that you cannot see yourself.
a _1,2 = 1, a _1,3 = 1, a _1,4 = 1,
All other elements are “0”, that is, a _{1, j} = 0 (j = 5, 6,..., 16)
Also, it is assumed that oneself cannot be seen and a _1,1 = 0

  Therefore, when the gateway 1 and each communication node i (i = 2, 3, 4,..., 16) have a positional relationship as shown in the network configuration diagram on the left side of FIG. As the adjacent matrix A, a matrix as shown on the right side of FIG. 2 is obtained. Each column having a non-zero value (a numerical value other than 0) on the k-th (k = 1, 2, 3,..., 16) row of the adjacency matrix A, that is, a value of “1” is included in each row. A communication node j that can be seen in one trial (hopping) from each of the corresponding gateway 1 or communication node i (i = 2, 3,..., 16) is shown. That is, for example, the gateway 1 in the first row of the adjacency matrix A indicates that three communication nodes 2, 3, and 4 existing in the vicinity are visible in one trial, and the second row From the first communication node 2, in addition to the gateway 1, the adjacent communication node 3 and the communication nodes 5 and 6 located in the vicinity are visible in one trial.

  Next, in order to show how many trials (hopping) each communication node i becomes visible, the power calculation result of the adjacency matrix A shown in FIG. 2 will be described with reference to FIG. FIG. 3 is an explanatory diagram illustrating the power calculation result of the adjacency matrix A illustrated in FIG. 2, FIG. 3A illustrates the same adjacency matrix A as in FIG. 2, and FIG. FIG. 3C shows the calculation result of the power of 3 of the adjacency matrix A (namely, adjacency matrix A ^ 3), and FIG. 3D shows the calculation result of the power of 2 of the adjacency matrix A ^ 2. 3 shows the calculation result of the power of the adjacency matrix A (ie, the adjacency matrix A 4), and FIG. 3E shows the calculation result of the power of the adjacency matrix A 5 (ie, the adjacency matrix A 5). (F) shows the calculation result of the sixth power of the adjacency matrix A (that is, the adjacency matrix A ^ 6).

Prior to the description of FIG. 3, the number of routes (number of ranks) from the gateway 1 to each communication node i will be described first for the adjacency matrix A shown in FIG. When the route is represented by P, the route P (N) _{i, j} indicates the number of routes that reach the communication node j from the communication node i by N hops. For example, P (1) _{i, j} indicates the number of routes that reach the communication node j from the communication node i in one hopping, and the number of routes P (1) _{i, j} is the above-mentioned a _i, It corresponds to the number _j is a non-zero value. That is, in the network configuration diagram of FIG. 2, the communication node i that reaches from the gateway 1 by one hopping is three communication nodes 2, 3, and 4, and the number of routes P (1) _{1, j} is 3 It is a piece.

P (2) _{i, j} indicates the number of paths that reach the communication node j from the communication node i by two hops, and the communication node i passes through one of the communication nodes n to the communication node j. What is necessary is just to obtain | require the sum total at the time of calculating | requiring the number of the path | routes to reach | attain, and applying the communication node n of a routing destination to all the communication nodes by following Formula (1).

As an example, the number P (2) ₁ , ₅ of routes reaching the communication node 5 by hopping twice from the gateway 1 communicates the route from the gateway 1 to the communication node 5 with reference to the network configuration diagram of FIG. When expressed in the order of the node numbers, the two paths are (1, 2, 5) or (1, 3, 5). That is, when the number of paths P (2) ₁ , ₅ is _expressed using the equation (1), the following equation (2) is obtained.

  In other words, the number P (2) i, j of paths that reach the communication node j from the communication node i by two hoppings is given by the expression (3) of the power of the adjacency matrix A, The number P (N) i, j of paths that reach the communication node j from the communication node i by N hoppings is given by the N power multiplier formula (4) of the adjacency matrix A.

  As shown in the network configuration diagram of FIG. 2, since the gateway 1 is assigned number 1 as a communication node, the other communication nodes (sensor nodes) are assigned numbers 2 to 16 and the communication nodes 2 to 2 are communicated. Shown as node 16. In order to determine how many times hopping from the gateway 1 can reach all the communication nodes from the communication node 2 to the communication node 16, the powers of the adjacent matrix A are raised to the second power, the third power,. It is sufficient to obtain the lowest power multiplier that increases all the elements in the first row corresponding to the gateway 1 so that they are non-zero values (values other than 0).

  Here, as a calculation result of the power of the adjacency matrix A in FIGS. 3B to 3E, a non-zero value (0) in the k-th (k = 1, 2, 3,..., 16) line. Each column that is a numerical value other than the communication node that can be seen by trials (hopping) of the number of times corresponding to a power multiplier from each of the gateway 1 or the communication node i (i = 2, 3,..., 16) corresponding to each row. j.

  That is, for example, from the gateway 1 in the first row of the adjacency matrix A in FIG. 3A, as described above, the three communication nodes 2, 3, and 4 are visible in the first trial. From the gateway 1 in the first row of the adjacency matrix A ^ 2 in FIG. 3B showing the power-of-two result of the adjacency matrix A, there are three communication nodes 2, 3 and 4 In addition, it is shown that three communication nodes 5, 6 and 7 are newly seen by the second trial.

  Further, when the lowest power factor at which all the elements in the first row corresponding to the gateway 1 are non-zero values (values other than 0) is obtained, the fourth power of the adjacency matrix A in FIG. This is the case of the adjacency matrix A 4), and indicates that all the communication nodes 2 to 16 can be reached if the gateway 1 tries (hopping) at least four times. In addition, in the fourth power of the adjacency matrix A in FIG. 3D, the values (21, 29, 18,..., 2) of the first row are changed from the gateway 1 to each communication node i (i = 2, 2). 3, 4,..., 16) The number of routes reaching each is shown.

  Next, a procedure for narrowing down and determining a route from the gateway 1 to each communication node i will be described with reference to FIG. FIG. 4 illustrates an example of a procedure for determining the hierarchy (rank) and path of each communication node i as a second procedure in the mesh network construction operation mode of the mesh network system for short-range wireless communication according to the present invention. It is explanatory drawing for. In FIG. 4, a procedure for narrowing down the route from the gateway 1 illustrated in the explanatory diagram of FIG. 2 to each communication node i (i = 2 to 16) and the hierarchy (rank) of each communication node i are determined. An example of the procedure, that is, the procedure for determining the communication node i of the hierarchy n, where n is the hierarchy of the communication node i that is not notified unless it is tried (hopping) n times, is shown.

  As shown in the calculation result of the power of the adjacency matrix A in FIG. 3, it is possible to reach all the communication nodes from the communication node 2 to the communication node 16 by performing at least four trials (hopping) from the gateway 1. Therefore, each communication node i is ranked in one of the four layers (ranks) of rank 1, rank 2, rank 3, and rank 4. More specifically, the first row corresponding to the gateway 1 in the adjacency matrix A in FIG. 3A and the first row corresponding to the gateway 1 in the power of the adjacency matrix A in FIG. 3B (A ^ 2). First, the first row corresponding to gateway 1 in the third power (A ^ 3) of the adjacency matrix A in FIG. 3C, gateway 1 in the fourth power (A ^ 4) of the adjacency matrix A in FIG. In each of the first row corresponding to the above, the process proceeds in the order of FIG. 3A, FIG. 3B, FIG. 3C, and FIG. As shown in FIG. 4 (A), the communication node i candidates that are ranked in rank 1, rank 2, rank 3, and rank 4 are determined (or determined) as shown in FIG. It is shown that it is the communication node i.

  Here, as shown in FIG. 4 (A), in the first row corresponding to the gateway 1 in the adjacency matrix A in the top FIG. 3 (A), it corresponds to a column of non-zero values (numerical values other than 0). The communication nodes 2, 3, and 4 are determined as the rank 1 rank (rank), and the first corresponding to the gateway 1 in the last power of the adjacency matrix A in FIG. 3D (A ^ 4). The communication nodes 12, 13, 14, and 16 corresponding to the column that first becomes a non-zero value (a numerical value other than 0) in the row are determined as the rank (rank) of rank 4 of the final rank. Moreover, it corresponds to the column which becomes a non-zero value (a numerical value other than 0) for the first time in the first row corresponding to the gateway 1 in the power of the adjacency matrix A in the middle of FIG. 3B (A ^ 2). The communication nodes 5, 6, and 7 select rank 2 from these three communication nodes as rank 2 candidates. Similarly, in the first row corresponding to the gateway 1 in the third power (A ^ 3) of the adjacency matrix A in the middle of FIG. 3C, this corresponds to a column that first becomes a non-zero value (a value other than 0) in the first row. The communication nodes 8, 9, 10, 11, and 15 select rank 3 from these five communication nodes as candidates for rank 3.

  Next, a procedure for determining (determining) the route of the communication node i of each rank of rank 1, rank 2, rank 3, and rank 4 will be described with reference to FIG. In general, as a procedure for determining a route, first, a communication node at the lowest rank that is determined as a communication node at the lowest layer n, that is, a lowermost layer that cannot be reached unless it is tried (hopping) n times A route from the communication node to the communication node i of the layer (n-1) that can be traced in the upper layer direction is determined. After that, by repeating the procedure of determining the route of the communication node i of the layer (n-2) that can be traced in the direction of one higher layer, the communication node i at the lowermost layer is changed to the uppermost layer. The route of the communication node i in each hierarchy (rank) is determined by narrowing down the route by sequentially tracing to the central gateway 1 of the network. When the gateway 1 is reached, the hierarchy (rank) and route of each communication node i are determined, and the configuration of the mesh network that performs short-range wireless communication is determined. Hereinafter, a specific example will be described with reference to FIG.

  First, in the item number 11 in FIG. 4C, as indicated by reference signs A, B, C, and D, from the communication nodes 12, 13, 14, and 16 that have been ranked as the lowest rank 4, respectively. The communication node i that can be traced up by one is obtained as a route.

  (1) Symbol A: The communication node immediately above the communication node 12 is only the communication node 8 as shown in the drawing on the right side of FIG. 4B, and the communication node 8 is one of the communication nodes 12. Confirmed as rank 3 above. Further, the route (12, 8) to the communication node 12 is also determined.

  (2) Code B: As shown in the drawing on the right side of FIG. 4B, the communication node immediately above the communication node 13 is only the communication node 9, and the communication node 9 is one of the communication nodes 13. Confirmed as rank 3 above. Further, the route (13, 9) to the communication node 13 is also determined.

  (3) Code C: As shown in the drawing on the right side of FIG. 4B, the communication node immediately above the communication node 14 is two communication nodes 10 and 15, and the communication nodes 10 and 15 are It is assumed that the candidate is rank 3 above the communication node 14. Two routes (14, 10) and (14, 15) to the communication node 14 are also candidates.

  (4) Symbol D: As shown in the drawing on the right side of FIG. 4B, the communication node immediately above the communication node 16 is only the communication node 11, and the communication node 11 is one of the communication nodes 16. Confirmed as rank 3 above. Further, the route (16, 11) to the communication node 16 is also determined.

  Next, in the item number 12 of FIG. 4C, as shown by the symbols E, F, G, H, and I, the communication nodes 8, 9, 11 and rank 3 candidates whose ranks are determined as rank 3 are determined. A communication node i that can be traced up one by one from each of the communication nodes 10 and 15 is obtained.

  (5) Symbol E: As shown in the drawing on the right side of FIG. 4B, the communication node immediately above the communication node 8 is only the communication node 5, and the communication node 5 is one of the communication nodes 8. Confirm as rank 2 above. Further, the route (8, 5) to the communication node 8 is also determined.

  (6) Symbol F: As shown in the drawing on the right side of FIG. 4B, the communication node immediately above the communication node 9 is two communication nodes 5 and 6, and the communication nodes 5 and 6 are It is assumed that the candidate is rank 2 above the communication node 9. However, the communication node 5 is determined as rank 2 above the communication node 8 in the above (5). Two routes (9, 5) and (9, 6) to the communication node 9 are also candidates.

  (7) Symbol G: As shown in the drawing on the right side of FIG. 4B, the communication node immediately above the communication node 10 is only the communication node 7, and the communication node 7 is described in (9) below. As shown, since it is determined as rank 2 above the communication node 11, it is also determined as rank 2 above the communication node 10. Therefore, the communication node 10 is determined at rank 3. Further, the route (10, 7) to the communication node 10 is also determined.

  (8) Symbol H: The communication node immediately above the communication node 15 is only the communication node 7 as shown in the drawing on the right side of FIG. 4B. As in the case, since it is determined as rank 2 above the communication node 11 as shown in (9) described later, it is also determined as rank 2 above the communication node 15. Therefore, the communication node 15 is determined at rank 3. Further, the route (15, 7) to the communication node 15 is also determined.

  (9) Symbol I: The communication node immediately above the communication node 11 is only the communication node 7 as shown in the drawing on the right side of FIG. 4B, and the communication node 7 is one of the communication nodes 11. Confirm as rank 2 above. Further, the route (11, 7) to the communication node 11 is also determined.

  Next, in the item number 13 of FIG. 4C, as indicated by the symbols J, K, and L, each of the communication nodes 5 and 7 whose rank is determined as rank 2 and the candidate communication node 6 of rank 2 are assigned. A communication node i that can be traced up is obtained.

  (10) Symbol J: The communication node immediately above the communication node 5 is two communication nodes 2 and 3 as shown in the drawing on the right side of FIG. , Has been confirmed as rank 1 above the communication node 5. The routes (5, 2) and (5, 3) to the communication node 5 are candidates.

  (11) Symbol K: The communication node immediately above the communication node 6 is two communication nodes 2 and 3 as shown in the drawing on the right side of FIG. , Has been confirmed as rank 1 above the communication node 6. Therefore, the communication node 6 is determined at rank 2. Further, routes (6, 2) and (6, 3) to the communication node 6 are candidates.

  (12) Code L: As shown in the drawing on the right side of FIG. 4 (B), the communication node one above the communication node 7 is two communication nodes 3 and 4, but the communication nodes 3 and 4 are , Has been confirmed as rank 1 above the communication node 7. Further, routes (7, 3) and (7, 4) to the communication node 7 are candidates.

  Next, in the item number 14 in FIG. 4C, as indicated by the symbols M, N, O, and P, the communication nodes 12, 13, 14, 16 at the end of the lowest layer (rank 4) and the rank 3 The route from the communication node 15 to the highest gateway 1 is determined by selecting one of the candidate routes.

  (13) Code M: From codes A, E, and J, the path from the communication node 12 to the gateway 1 is either (12, 8, 5, 2, 1) or (12, 8, 5, 3, 1). However, for the time being, the route (12, 8, 5, 2, 1) is selected and determined.

  (14) Code N: Based on codes B, F, J, K, and M, the route from the communication node 13 to the gateway 1 is already used in the code M by the higher-order route (.,.., 5, 2, 1) Since it has already been completed, the route (13, 9, 6, 3, 1) that is not yet used is selected and determined.

  (15) Code O: Based on codes C, G, H, L, and N, the route from the communication node 14 to the gateway 1 is already used by the code N in the higher-order route (.,..., 3, 1). Since it has already been completed, the route (14, 10, 7, 4, 1) that is not yet used is selected and determined. Similarly, the route from the communication node 15 to the gateway 1 is determined by selecting (15, 7, 4, 1).

  (16) Code P: From the codes D, I, L, and N, the route from the communication node 16 to the gateway 1 is a route that has not been used as in the case of (15) (16, 11, 7, 4,1) is selected and determined.

(Third Procedure): Notification of Hierarchy and Route to Each Communication Node In the second procedure, the gateway 1 determines the hierarchy (rank) and route of each communication node i for short-range wireless communication. When the configuration of the mesh network is determined, the gateway 1 that knows the route to each communication node i next designates the route to each communication node i, as shown in FIG. Using the pseudo unicast communication method in which each communication node i is designated as a single destination, network information on the determined hierarchy (rank) of each communication node i and the route indicating the transmission / reception destination is obtained for each communication. Notify node i. FIG. 5 is a third procedure in the mesh network construction operation mode of the mesh network system for short-range wireless communication according to the present invention, in which network information related to the hierarchy (rank) and route of each communication node is assigned to each corresponding communication node. It is explanatory drawing for demonstrating an example of the procedure notified with respect to it.

  The network information notification operation by the pseudo unicast communication method from the gateway 1 to each communication node i shown in FIG. 5 is performed according to the following procedure.

  (1) The gateway 1 positioned at the node of the hierarchy 0 has a number indicating each hierarchy (rank) for each communication node i ranked in the next hierarchy 1 by a pseudo unicast communication method. Information about each higher-order gateway 1 of each communication node i and each communication node i ranked in the subordinate hierarchy 2 is notified. For example, the gateway 1 notifies the communication node 2 of the hierarchy 1 of the number information indicating the hierarchy 1 as shown by the thick solid arrow line in FIG. And information regarding the communication node 5 of the subordinate hierarchy 2 are notified.

  In addition, the communication node 3 in the hierarchy 1 is notified of the number information indicating the hierarchy 1 as shown by the thick dashed-dotted arrow line in FIG. Information about the communication node 6 of the hierarchy 2 is notified. Further, the communication node 4 of the hierarchy 1 is notified of the number information indicating the hierarchy 1 as shown by the thick dashed arrow line in FIG. 5, and the higher-order gateway 1 determined as the route and the hierarchy below it. Information regarding the two communication nodes 7 is notified.

  (2) Next, the gateway 1 positioned at the node of the hierarchy 0 is connected to the communication node i of the subordinate hierarchy 2 via the communication node i of the hierarchy 1 through the pseudo unicast communication method. The number indicating each layer (rank) and the information regarding the communication node i ranked in the upper layer 1 of each communication node i and each communication node i ranked in the subordinate layer 3 are notified. For example, the gateway 1 notifies the communication node 5 of the hierarchy 2 of the number information indicating the hierarchy 2 via the communication node 2 of the hierarchy 1 as indicated by the thick solid arrow in FIG. At the same time, information about the communication node 2 of the higher hierarchy 1 and the communication node 8 of the subordinate hierarchy 3 determined as the route is notified.

  In addition, the communication node 6 of the hierarchy 2 is notified of the number information indicating the hierarchy 2 via the communication node 3 of the hierarchy 1 as shown by the thick dashed-dotted arrow line in FIG. Information on the communication node 3 of the higher hierarchy 1 determined as the route and the communication node 9 of the subordinate hierarchy 3 is notified. In addition, as shown by the thick dashed arrow line in FIG. 5, the communication node 7 of the hierarchy 2 is notified of the number information indicating the hierarchy 2 via the communication node 4 of the hierarchy 1 and the route. The information about the communication node 4 of the upper hierarchy 1, the communication node 10, the communication node 11, and the communication node 15 of the subordinate hierarchy 3 determined as is notified.

  (3) Next, the gateway 1 positioned at the node of the hierarchy 0 uses the pseudo unicast communication method, via the communication node i of the hierarchy 1 and the communication node i of the subordinate hierarchy 2 respectively. The communication node i in the hierarchy 3 below is numbered in the hierarchy 4 and the number indicating the respective hierarchy (rank) and the communication node i ranked in the hierarchy 2 higher than each communication node i. Information about each communication node i is notified. For example, the gateway 1 passes through the communication node 2 in the hierarchy 1 and the communication node 5 in the hierarchy 2 to the communication node 8 in the hierarchy 3, as indicated by the thick solid arrow in FIG. The number information indicating the layer 3 is notified, and the information regarding the communication node 5 of the higher layer 2 and the communication node 12 of the subordinate layer 4 determined as the route is notified.

  Further, for the communication node 9 in the hierarchy 3, as indicated by the thick dashed-dotted arrow line in FIG. 5, the hierarchy 3 is passed through the communication node 3 in the hierarchy 1 and the communication node 6 in the hierarchy 2. The number information shown is notified, and information related to the communication node 6 of the higher hierarchy 2 and the communication node 13 of the subordinate hierarchy 4 determined as the route is notified. Further, the communication node 10 and the communication node 11 in the hierarchy 3 are routed through the communication node 4 in the hierarchy 1 and the communication node 7 in the hierarchy 2 as indicated by the thick broken line in FIG. The number information indicating the layer 3 is notified, respectively, and the information regarding the communication node 7 of the higher layer 2 determined as each route, the communication node 14 and the communication node 16 of the subordinate layer 4 is notified. Further, for the communication node 15 in the hierarchy 3, as indicated by the thick broken arrow line in FIG. 5, the hierarchy 3 is indicated via the communication node 4 in the hierarchy 1 and the communication node 7 in the hierarchy 2. The number information is notified, but only the information regarding the communication node 7 of the upper hierarchy 2 determined as the route is notified, and the communication node of the hierarchy 4 below is notified.

  (4) After that, the gateway 1 positioned at the node of the hierarchy 0 uses the same procedure as the above-described procedure by the pseudo unicast communication method until reaching the communication node i positioned at the lowest layer. , The communication node i in the hierarchy 1, the communication node i in the hierarchy 2 under each, ..., the communication node i in the hierarchy (n-1) under each, and the communication node i in the hierarchy n under each On the other hand, the numbers indicating the respective hierarchies (ranks) and the respective communication nodes i ranked in the upper hierarchy (n-1) of the respective communication nodes i and the respective subordinate hierarchies (n + 1) The operation of notifying information related to the communication node i is repeated. When the communication node i positioned at the lowest layer is reached, there is no subordinate communication node determined as the route, so the communication node of the higher layer determined as the route is notified together with the notification of the hierarchy (rank) Only the information related to i is notified, and notification that there is no communication node in the hierarchy below it. After that, since the network information regarding the hierarchy (rank) and the route is notified to all the communication nodes i, the notification operation of the network information regarding the hierarchy (rank) and the route is finished.

  For example, the gateway 1 connects the communication node 2 of the hierarchy 1, the communication node 5 of the hierarchy 2, and the hierarchy to the communication node 12 of the hierarchy 4 of the lowest layer, as indicated by the thick solid arrow line in FIG. The number information indicating the hierarchy 4 is notified via the communication node 8 of 3 and only the information related to the communication node 8 of the higher hierarchy 3 determined as the route is notified, and there is no communication node of the subordinate hierarchy. To be notified. Further, for the communication node 13 of the lowest layer, the communication node 13, as indicated by the thick dashed line in FIG. 5, the communication node 3 of the layer 1, the communication node 6 of the layer 2, and the communication of the layer 3. The node 9 is notified of the number information indicating the hierarchy 4, and is also notified of only the information related to the communication node 9 of the upper hierarchy 3 determined as the route, and notifies that there is no communication node of the subordinate hierarchy. .

  For the communication node 14 at the lowest layer, the communication node 14 at the layer 1, the communication node 7 at the layer 2, and the communication node at the layer 3, as shown by the thick broken line in FIG. 10 and the number information indicating the hierarchy 4 are notified, only the information about the communication node 10 of the higher hierarchy 3 determined as the route is notified, and the communication node of the subordinate hierarchy does not exist is notified. . Further, for the communication node 16 at the lowest layer, the communication node 16 at the layer 1, the communication node 7 at the layer 2, and the communication node at the layer 3, as indicated by the thick broken line in FIG. 11 is notified of the number information indicating the hierarchy 4, and only the information regarding the communication node 11 of the higher hierarchy 3 determined as the route is notified, and notifies that there is no communication node of the subordinate hierarchy. .

(Fourth procedure): Notification of the start of service of the entire network In the third procedure, the gateway 1 transmits network information on the hierarchy (rank) and route of each communication node i to all the communication nodes i. When the notification is completed, the gateway 1 next notifies all communication nodes i of the start of the service of the entire network by a pseudo broadcast communication method as shown in FIG. FIG. 6 is a procedure for notifying all communication nodes of information indicating that the service of the entire network is started as a fourth procedure in the mesh network construction operation mode of the mesh network system for short-range wireless communication according to the present invention. It is explanatory drawing for demonstrating an example.

  The notification operation of the service start of the entire network by the pseudo broadcast communication method from the gateway 1 to all the communication nodes i is performed according to the following procedure.

  (1) The gateway 1 positioned at the node of the hierarchy 0 notifies each communication node i ranked in the next hierarchy 1 of the information regarding the service start of the entire network by a pseudo broadcast communication method. For example, for the communication nodes 2, 3, and 4 in the hierarchy 1, the gateway 1 uses the pseudo broadcast communication method to provide services for the entire network all at once, as indicated by the thick solid arrows in FIG. 6. Broadcast information about the start.

  (2) The communication nodes 2, 3, and 4 in the hierarchy 1 that have received the pseudo broadcast notification from the gateway 1 are all the communication nodes i in the hierarchy 2 that are located under the second and third procedures. Therefore, the information regarding the service start of the entire network is notified to all the subordinate layer 2 communication nodes i by the pseudo broadcast communication method. For example, the communication node 2 in the hierarchy 1 simultaneously transmits the pseudo-broadcast communication method to the communication nodes 5 and 6 in the hierarchy 2 under the pseudo broadcast communication method as indicated by the thick solid arrow in FIG. , Informs about the service start of the entire network.

  Further, the communication node 3 in the hierarchy 1 performs pseudo broadcast communication with respect to the communication node 5, the communication node 6, and the communication node 7 in the subordinate hierarchy 2, as indicated by thick solid arrow lines in FIG. 6. By this method, information related to the start of services for the entire network is notified at once. Further, the communication node 4 in the hierarchy 1 relates to the service start of the entire network by the pseudo broadcast communication method as shown by the thick solid arrow in FIG. 6 with respect to the communication node 7 in the hierarchy 2 below. Notify information.

  (3) Each of the communication nodes 5, 6, 7 of the hierarchy 2 that has received the pseudo broadcast notification from each of the communication nodes 2, 3, 4 of the hierarchy 1 is located under each of them in the second and third procedures. Since all the communication nodes i in the hierarchy 3 are grasped, the information regarding the service start of the entire network is provided to all the communication nodes i in the grasped hierarchy 3 by the pseudo broadcast communication method. Notice. For example, the communication node 5 in the hierarchy 2 is connected to the communication node 8 and the communication node 9 in the hierarchy 3 by the pseudo broadcast communication method as shown by a thick solid arrow line in FIG. To inform about the service start of the entire network.

  Further, the communication node 6 in the hierarchy 2 relates to the start of service of the entire network by the pseudo broadcast communication method as shown by the thick solid arrow line in FIG. 6 with respect to the communication node 9 in the hierarchy 3 below. Notify information. Further, the communication node 7 in the hierarchy 2 performs pseudo broadcast communication with respect to the communication node 10, the communication node 11, and the communication node 15 in the subordinate hierarchy 3 as indicated by thick solid arrow lines in FIG. 6. By this method, information related to the start of services for the entire network is notified at once.

  (4) After that, the communication node i in each layer is subordinated to each other in the same procedure as described above by the pseudo broadcast communication method until the communication node i positioned in the lowest layer is reached. The operation of notifying the communication node i in the next layer of the information regarding the service start of the entire network is repeated. When the communication node i positioned at the lowest layer is reached, there is no subordinate communication node to be notified of information about the service start of the entire network by the pseudo broadcast communication method. The notification operation is terminated.

  For example, the communication node 8 in the hierarchy 3 is connected to the communication node 12 in the hierarchy 4 in the lowest layer by using a pseudo broadcast communication system as shown by a thick solid arrow in FIG. Notify information about the overall service start. Further, the communication node 9 in the hierarchy 3 is connected to the communication node 13 in the lowest hierarchy in the hierarchy 3 by the pseudo broadcast communication system as shown by the thick solid arrow in FIG. Notify information about the overall service start.

  Further, the communication node 10 in the hierarchy 3 is connected to the communication node 14 in the lowest hierarchy in the hierarchy by using a pseudo broadcast communication system as shown by a thick solid arrow in FIG. Notify information about the overall service start. In addition, the communication node 15 in the hierarchy 3 is also connected to the network node 14 in the hierarchy 4 in the lowest layer by the pseudo broadcast communication method as shown by the thick solid arrow in FIG. Notify information about the overall service start. Further, the communication node 11 in the hierarchy 3 is connected to the communication node 16 in the lowest hierarchy under the hierarchy by using a pseudo broadcast communication system as shown by a thick solid arrow in FIG. Notify information about the overall service start.

(Fifth Procedure): Data Transmission / Reception Operation in Network Service Providing Operation Mode, for example, Normal Measurement Operation Mode In the fourth procedure, when the network-wide service start notification is completed for all communication nodes i, the short-range wireless communication mesh The mesh network construction operation mode of the network system is terminated, the network service providing operation mode (normal measurement operation mode in the case of a sensor network) is entered, and the service as the network system is started. Here, when the communication node i is a sensor node that measures the target information, as described above, as the service providing operation mode of the network system, the measurement data regarding the measurement result in each sensor node is transmitted and received. Transition to normal measurement operation mode.

  Each sensor node i (communication node i) uses the third procedure in the mesh network construction operation mode as the route information for data transmission / reception, and the sensor node i (communication node i) located above itself and its subordinates The sensor node i (communication node i) located at is notified in advance by the pseudo unicast communication method from the gateway 1 and grasped. Therefore, when the measurement data to be transmitted to the gateway 1 is generated, each sensor node i (communication node i) performs the measurement with respect to the sensor node i (communication node i) positioned above itself. Send data. In addition, the sensor node i (communication node i) that has received the measurement data from the subordinate sensor node i (communication node i) transfers the measurement data to the sensor node i (communication node i) positioned above itself. This operation is repeated until the sensor node i (communication node i) of the highest hierarchy 1 is reached. When sensor data i (communication node i) in the highest hierarchy 1 receives the measurement data, the received measurement data is transferred to the gateway 1 corresponding to hierarchy 0.

  For example, the measurement data transmission operation from each sensor node i (communication node i) located in the lowest layer to the gateway 1 is performed according to the following procedure as shown in the explanatory diagram of FIG. FIG. 7 is an explanatory diagram for explaining an example of a procedure in the normal measurement operation mode of the mesh network system for short-range wireless communication according to the present invention as the fifth procedure, and is located in the hierarchy 4 of the lowest layer. A transmission path in a case where measurement data measured in each sensor node i (communication node i) is transmitted to the gateway 1 corresponding to the hierarchy 0 is shown. In addition, in FIG. 7, the case where the mesh network is comprised as a sensor network is illustrated.

  (1) For example, the sensor node 12 (communication node 12) of the hierarchy 4 is the hierarchy designated as the upper transmission destination of the route information, as indicated by the thick solid arrow in FIG. 3 to the sensor node 8 (communication node 8). When the sensor node 8 (communication node 8) in the hierarchy 3 receives the measurement data from the sensor node 12 (communication node 12), as shown by a thick solid arrow line in FIG. The information is transferred to the sensor node 5 (communication node 5) in the hierarchy 2 designated as the higher-order transmission destination of information.

  When the sensor node 5 (communication node 5) in the hierarchy 2 receives the measurement data from the sensor node 8 (communication node 8), the received measurement data is routed as indicated by a thick solid arrow in FIG. The information is transferred to the sensor node 2 (communication node 2) in the hierarchy 1 designated as the higher-order transmission destination of information. When the sensor node 2 (communication node 2) in the hierarchy 1 receives the measurement data from the sensor node 5 (communication node 5), the received measurement data is routed as indicated by a thick solid arrow in FIG. The information is transferred to the gateway 1 corresponding to the hierarchy 0 designated as the higher-order transmission destination of information, that is, to the gateway 1 that is the final transmission destination.

  That is, the measurement data measured at the sensor node 12 (communication node 12) of the lowest layer 4 is a pseudo unicast communication method from the gateway 1 as shown by the thick solid arrow line in FIG. Is transferred to the gateway 1 via the route (12, 8, 5, 2, 1) based on the route information notified in advance.

  (2) In addition, the measurement data measured at the sensor node 13 (communication node 13) in the hierarchy 4 is a pseudo unicast communication method from the gateway 1 as shown by the thick dashed-dotted arrow line in FIG. The gateway 1 via the route (13, 9, 6, 3, 1) designated as a route different from the case of the sensor node 12 (communication node 12) based on the route information notified in advance by Forwarded to

  (3) In addition, the measurement data measured at the sensor node 14 (communication node 14) in the hierarchy 4 is obtained by a pseudo unicast communication method from the gateway 1 as indicated by a thick broken arrow line in FIG. Based on the route information notified in advance, the route is designated as a route different from the case of the sensor node 12 (communication node 12) and the sensor node 13 (communication node 13) (14, 10, 7, 4, 1). Are transferred to the gateway 1 via Further, the measurement data measured at the sensor node 16 (communication node 16) in the hierarchy 4 is also notified in advance by the pseudo unicast communication method from the gateway 1, as indicated by the thick broken line in FIG. Routes (16, 11, 7, 4, 1) that are designated as different routes from the sensor node 12 (communication node 12) and sensor node 13 (communication node 13) based on the route information And transferred to the gateway 1.

  In the network service providing operation mode, for example, the normal measurement operation mode, the gateway 1 or the server 20 on the cloud constantly monitors the data transmission operation transmitted from each communication node i for a predetermined time. When it is detected that the data transmission operation is not performed, it is determined that a network operation abnormality has occurred, and a network service is provided to all communication nodes i by a pseudo broadcast communication method. The operation in the operation mode, for example, the normal measurement operation mode is stopped, the operation is shifted to the mesh network construction operation mode, and the mesh network is reconstructed.

(Sixth procedure): Transmission of control information to a specific communication node The gateway 1 also has a function of controlling each sensor node i (communication node i). For example, when it is requested by the above-described fifth procedure that control is performed on the sensor node i (communication node i) as a kind of measurement data from the specific sensor node i (communication node i), the gateway 1 creates control information for performing the requested control, and transmits the created control information to the sensor node i (communication node i) by a pseudo unicast communication method.

  Here, as described in the second procedure, the gateway 1 indicates from which sensor node i (communication node i) each sensor node i (communication node i) is visible, that is, which sensor node i (communication node i). The route information indicating whether or not the node i) is wirelessly connected is known in advance. Therefore, when the gateway 1 attempts to transmit control information to a specific sensor node i (communication node i), the gateway 1 performs a transmission operation in the following procedure.

  (1) First, the gateway 1 provides route information to a specific sensor node i (communication node i) as a destination of the control information in addition to control information for the specific sensor node i (communication node i). Attached to the control information, transmitted to the sensor node i (communication node i) in the hierarchy 1 located on the route reaching the destination sensor node i (communication node i) by a pseudo unicast communication method can do.

  (2) Upon receiving the control information from the gateway 1, the sensor node i (communication node i) of the hierarchy 1 subordinates from the received route information when the destination of the received control information is not addressed to itself. Reads information related to the sensor node i (communication node i) in the next layer 2 and receives the received control information for the sensor node i (communication node i) in the next layer 2 located on the route. Along with the route information, a pseudo unicast communication method is used for transmission.

  Even after (3), the sensor node i (communication node i) of each layer will receive the received control information together with the received route information until it reaches the sensor node i (communication node i) designated as the destination. By the pseudo unicast communication method, the transfer operation is repeated for the sensor node i (communication node i) in each subordinate hierarchy according to the same procedure as described above. When the sensor node i (communication node i) designated as the destination is reached, the sensor node i (communication node i) performs control based on the received control information.

  As described above, in the above embodiments from (first procedure) to (sixth procedure), the mesh network construction operation mode and the network service provision operation mode, for example, the normal measurement operation mode, are used. There are two network operation modes. In the mesh network construction operation mode, the gateway 1 or the server 20 on the cloud acquires a list of adjacent communication nodes i capable of wireless communication from each communication node i, and wireless communication is possible based on the acquired list. Network information about the role (hierarchy (rank)) and path information of each communication node i to each communication node i by pseudo unicast communication, and by pseudo broadcast communication, All communication nodes i are instructed to start providing network services, for example, to start the normal measurement operation mode or to re-enter the mesh network construction operation mode.

  On the other hand, in the network service providing operation mode (for example, the normal measurement operation mode in the case of a sensor network), each communication node i transmits to the destination according to the route information notified from the gateway 1 or the server 20 side in the cloud. Data (for example, measurement data measured by the sensor node when the communication node i is a sensor node) is transmitted. The gateway 1 or the server 20 on the cloud monitors the transmission data from each communication node i, and if the transmission data (measurement data) is not notified during a predetermined time, the network It is determined that the operation is abnormal, and the network service is stopped (for example, in the case of the sensor network, the operation of transmitting the sensor information measurement result is stopped) and the mesh network by pseudo broadcast communication. By instructing the transition to the construction operation mode, the transition to the mesh network construction operation mode is performed and the mesh network is reconstructed.

  In addition, as a short-range wireless communication protocol used in the above embodiment, an existing short-range wireless communication standard (such as ZIGBEE or BLE (Bluetooth (registered trademark) Low Energy)) may be used. Even when the wireless communication standard is applied, as described above, the wireless communication management on the mesh network is facilitated, the overhead of the mesh network is reduced, and the mesh wireless communication can be performed efficiently. ing. Furthermore, the network gateway 1 or the server 20 on the cloud is provided with a management function for the entire network, and appropriately assigns a hierarchy to each communication node i and determines a route according to the network situation. As a result, it has a configuration that has the advantages of both the communication method in the non-mesh network and the communication method in the mesh network, thereby realizing high efficiency of wireless communication.

  In addition, network information related to the hierarchy (rank) and route of each communication node i is centrally created and managed by the gateway 1 or the server 20 on the cloud, so that the failure status and traffic status on the network can be easily visualized. Thus, it can be presented to the network administrator. Further, for example, when the communication node i is a miniaturized sensor node for configuring a sensor network, it is generally battery-driven, and only a limited CPU (Central Processing Unit) performance is provided. In many cases, it is impossible to provide a complicated function on a node. However, in this embodiment, since the complicated network management function is provided on the gateway 1 or the server 20 side in the cloud, the communication node i may be a device equipped with a low-performance CPU. Furthermore, it is possible to increase the battery driveable time of the sensor node (communication node).

(Other embodiments)
In the description of the above embodiment, the gateway 1 creates and manages network information related to the hierarchy (rank) and route of each communication node i constituting the mesh network system for short-range wireless communication. Instead of the gateway 1, the network information may be created and managed using a server on the cloud to which the gateway is connected, or instead of using the gateway, a kind of gateway When a mesh network is configured using a router, the router may create and manage the network information.

  Further, as shown in FIG. 8, the network information about the hierarchy (rank) and the route regarding each communication node i may be distributed and managed in a plurality of gateways and routers. FIG. 8 is a network configuration diagram showing a network configuration example different from FIG. 1 of the mesh network system for short-range wireless communication according to the present invention. Unlike FIG. 1, each network is distributed to a plurality of gateways. A network configuration example in the case of managing network information related to the hierarchy (rank) and route of the communication node i is shown.

  That is, the network configuration in FIG. 8 illustrates a case where three sets of sub-networks having the same network configuration as in FIG. 1 are prepared, and the communication belonging to each of the three gateways 1a, 1b, and 1c. The server 21 on the cloud for managing the network information related to the nodes 2a to 16a, 2b to 16b, and 2c to 16c in a distributed manner and performing the cooperative operation of the three gateways 1a, 1b, and 1c is further set as the highest layer. The case where it is provided is illustrated.

  Further, in the above-described embodiment, the information mainly instructing the start of the network service, for example, the start of the normal measurement operation mode, is mainly described as the information notified to all the communication nodes by the pseudo broadcast communication method. In addition to such information, as described above, it is information for instructing the stop of the network service (for example, the stop of the normal measurement operation mode in the case of the sensor network) and the information for instructing the re-transition to the mesh network construction operation mode. Of course.

  In addition, each communication node i illustrated in the above-described embodiment includes a sensor node that includes a sensor capable of measuring target information and a wireless communication function capable of performing wireless communication, as described above. Of course, it is also possible to configure. When configuring a sensor network with such sensor nodes, for example, for each sensor node, only a hierarchy (rank) may be determined, and route information for transmitting / receiving measurement data may not be determined. As described above, when route information is not determined, measurement data in each sensor node is transmitted to a sensor node having a lower hierarchy (rank), and control data from the gateway has a higher hierarchy (rank). By operating to transmit to the other sensor node, the amount of data communication can be reduced as compared with the case of the prior art.

(Explanation of effect of embodiment)
As described in detail above, the following effects can be achieved in the present embodiment.

  In the mesh network system for short-range wireless communication in the present embodiment, the communication amount for determining the route for data transmission / reception is significantly reduced as compared with the mesh network system for short-range wireless communication in the prior art. Can do.

  In other words, in a conventional mesh network system, when a certain communication node transmits data to a destination node such as a gateway, is the final destination node such as a gateway found for the surrounding communication node? Inquire whether or not. The neighboring communication nodes that have received the inquiry further repeat the operation of making the same inquiry to the neighboring communication nodes until a final destination node, for example, a gateway is found. As a result, for example, with respect to each communication node, on average, three peripheral communication nodes are visible, and a node, for example, a gateway, four layers ahead from a specific communication node to transmit data is the destination In this case, 3 ^ 4 = 81 transmission operations are required at least before the data transmission path is determined.

  In contrast, in the mesh network system according to the present embodiment, as described in the fifth procedure, the hierarchy (rank) and path of each sensor node i (communication node i) are determined in advance in the gateway 1. Thus, each sensor node i (communication node i) is notified in advance by a pseudo unicast communication method, and therefore, the sensor node i (communication node i) of the lowest layer 4 is layer 0 that is four layers ahead. Even when measurement data is transmitted to the gateway 1 positioned at the node, the transmission operation can be completed by performing only four measurement data transmission operations.

  Further, in the mesh network system for short-range wireless communication in the present embodiment, the route information of each communication node i is configured and managed on the server side on the gateway 1 or the cloud. The role (number of ranks) of the communication node i and the amount of data passing through each communication node i can be visualized and easily managed.

  Further, in the mesh network system for short-range wireless communication in the present embodiment, unlike the conventional route fixed type network system, for example, even if the communication node i to be relayed fails and communication becomes impossible, On the gateway 1 or the server side on the cloud, it is possible to reconfigure the network and restart the service.

  The configuration of the preferred embodiment of the present invention has been described above. However, it should be noted that such embodiments are merely examples of the present invention and do not limit the present invention in any way. Those skilled in the art will readily understand that various modifications and changes can be made according to a specific application without departing from the gist of the present invention.

1 Gateway 1a Gateway 1b Gateway 1c Gateway 2 Communication node (sensor node)
2a Communication node (sensor node)
2b Communication node (sensor node)
2c Communication node (sensor node)
3 Communication node (sensor node)
3a Communication node (sensor node)
3b Communication node (sensor node)
3c Communication node (sensor node)
4 Communication node (sensor node)
4a Communication node (sensor node)
4b Communication node (sensor node)
4c Communication node (sensor node)
...
16 Communication node (sensor node)
16a Communication node (sensor node)
16b Communication node (sensor node)
16c Communication node (sensor node)
20 server 20a server 20b server 20c server 21 server

Claims (10)

A mesh network system for short-range wireless communication that has a plurality of communication nodes and a gateway having a network management function, and performs mesh wireless communication between the communication nodes or between the communication node and the gateway,
The gateway has two network operation modes, ie, a mesh network construction operation mode and a network service provision operation mode, as the network management function. In the mesh network construction operation mode, By collecting information about surrounding communication nodes capable of wireless communication with the communication node, creating network information about the hierarchy and route of each of the communication nodes, by a pseudo unicast communication method, After notifying each of the communication nodes capable of wireless communication of the network information regarding the corresponding hierarchy and route, and building a mesh network, wireless communication is possible by a pseudo broadcast communication method. All the communication nodes Against de notifies an instruction to start the network services, is shifted from the mesh network construction mode of operation to the network service provider operating mode,
On the other hand, each of the communication nodes stores the network information notified from the gateway by the pseudo unicast communication method in the mesh network construction operation mode, and the network by the pseudo broadcast communication method from the gateway. After receiving an instruction to start a service and shifting to the network service providing operation mode, the data transmission / reception operation is performed according to the stored network information when data transmission / reception is performed. Communication mesh network system.   The hierarchy of each of the communication nodes is based on the result of performing an adjacent matrix indicating whether the gateway and each of the communication nodes are in a state in which wireless communication is possible with any of the communication nodes and the power of the adjacent matrix. And the path of each of the communication nodes starts from the communication node ranked in the lowest layer, and is routed to any one of the upper layers capable of wireless communication. 2. The mesh network system for near field communication according to claim 1, wherein a procedure for obtaining a route is determined by repeatedly moving to a higher hierarchy until the gateway corresponding to the highest hierarchy is reached.   In the network service providing operation mode, the gateway constantly monitors a data transmission operation in which data is transmitted from each communication node, and detects that the data transmission operation has not been performed for a predetermined time. If it is determined that an abnormality in network operation has occurred, and after stopping the operation of the network service providing operation mode for all the communication nodes by a pseudo broadcast communication method, the mesh network The mesh network system for near field communication according to claim 1 or 2, wherein the mesh network is reconstructed by shifting to a construction operation mode.   The network management function implemented in the gateway is performed on the server side in the case where a router on the server to which the gateway is connected or the gateway is located instead of the gateway. The mesh network system for near field communication according to any one of claims 1 to 3.   The communication node is configured as a sensor node having at least a wireless communication function capable of performing wireless communication with a sensor capable of measuring target information. A mesh network system for short-range wireless communication according to claim 1. Short-range wireless communication in a mesh network system for short-range wireless communication, having a plurality of communication nodes and a gateway having a network management function, and performing mesh wireless communication between the communication nodes or between the communication node and the gateway A method,
The gateway has two network operation modes, ie, a mesh network construction operation mode and a network service provision operation mode, as the network management function. In the mesh network construction operation mode, By collecting information about surrounding communication nodes capable of wireless communication with the communication node, creating network information about the hierarchy and route of each of the communication nodes, by a pseudo unicast communication method, After notifying each of the communication nodes capable of wireless communication of the network information regarding the corresponding hierarchy and route, and building a mesh network, wireless communication is possible by a pseudo broadcast communication method. All the communication nodes Against de notifies an instruction to start the network services, is shifted from the mesh network construction mode of operation to the network service provider operating mode,
Meanwhile, each of the communication nodes stores the network information notified to each of the gateways by the pseudo unicast communication method in the mesh network construction operation mode, and the network is transmitted from the gateways by the pseudo broadcast communication method. After receiving an instruction to start a service and shifting to the network service providing operation mode, the data transmission / reception operation is performed according to the stored network information when data transmission / reception is performed. Communication method.   The hierarchy of each of the communication nodes is based on the result of performing an adjacent matrix indicating whether the gateway and each of the communication nodes are in a state in which wireless communication is possible with any of the communication nodes and the power of the adjacent matrix. And the path of each of the communication nodes starts from the communication node ranked in the lowest layer, and is routed to any one of the upper layers capable of wireless communication. 7. The short-range wireless communication method according to claim 6, wherein a procedure for obtaining a route is determined by repeatedly moving to a higher hierarchy until the gateway corresponding to the highest hierarchy is reached.   In the network service providing operation mode, the gateway constantly monitors a data transmission operation in which data is transmitted from each communication node, and detects that the data transmission operation has not been performed for a predetermined time. If it is determined that an abnormality in network operation has occurred, and after stopping the operation of the network service providing operation mode for all the communication nodes by a pseudo broadcast communication method, the mesh network 8. The short-range wireless communication method according to claim 6 or 7, wherein the mesh network is reconstructed by shifting to a construction operation mode.   The network management function implemented in the gateway is performed on the server side in the case where a router on the server to which the gateway is connected or the gateway is located instead of the gateway. The short-range wireless communication method according to claim 6, wherein:   10. A short-range wireless communication program, wherein the short-range wireless communication method according to claim 6 is implemented as a program executable by a computer.