JP5586743B2 - Wireless node device - Google Patents

Description

  The present invention relates to a radio node apparatus that forms an ad hoc multi-hop communication network by configuring a communication path that uses a subordinate radio node as a relay terminal or a terminal, or functions as a radio node under these.

  Ad-hoc multi-hop communication systems enable end-to-end communication between wireless nodes without going through large-scale facilities such as wireless base stations and trunk transmission lines where a large amount of traffic is concentrated. Since expansion, relocation, removal, etc. can be easily realized, they are being used in various fields such as measurement systems, monitoring systems, and the like.

As prior art relevant to the present invention, there are Patent Documents 1 to 3 listed below.
Patent Document 1 states that “in a multi-hop communication network in which a plurality of communication terminals that transmit each measured data to a data collection device that collects data is connected in a tree structure, input communication network data is represented. Two or more non-overlapping ones with each communication terminal serving as a base for collecting communication data among the communication terminals sending data to the data collection device by repeating data transfer via other communication terminals according to the tree structure One or more communication groups of communication terminals are formed, and communication data in each communication group is aggregated and transmitted to the data collection device by the communication terminals serving as the collection bases. A data collection system that is characterized in that the number of times is reduced is disclosed.

  Patent Document 2 discloses that “in an ad hoc network, when communication is performed, the number of hops as the entire system is reduced by referring to a routing table in which route information is described, thereby realizing power saving in the entire network”. A wireless terminal device characterized by this point is disclosed.

Patent Document 3 describes a wireless transmission device, a wireless reception device, and a wireless communication device that are characterized in that “the power saving is achieved by reducing the number of intermittent receptions in a specific power-saving wireless system such as a wireless meter reading system or a home network”. A transmission / reception device is disclosed.
Patent Document 4 states that “in a wireless ad hoc network to which TCP or a protocol similar to TCP is applied, a communication station counts the amount of communication passing through its own communication station, and corresponds to the counted communication amount. The amount of traffic passing through its own communication station is determined by setting the timeout time for starting retransmission of packets according to the determined backoff size. Accordingly, a communication method characterized in that it is possible to set a favorable timeout time according to the above and effectively prevent deterioration of transmission characteristics is disclosed.

JP 2006-295813 A JP 2006-325142 A JP 2008-11048 A JP 2004-15746 A

By the way, in the conventional ad hoc multi-hop communication system, since the communication path is fixed, the power consumption increases remarkably and the battery is frequently replaced as the number of communication paths intervening as relay terminals increases. I had to be.
An object of the present invention is to provide a wireless node device in which the difference in power consumption between nodes is greatly reduced without changing the hardware configuration.

In the first aspect of the present invention, the communication unit is arranged under a specific wireless node forming an ad hoc multi-hop communication network, and serves as a relay terminal or a terminal of a specific communication path formed by the specific wireless node. Operate. The notification means reconfirms an adjacent wireless node that can be adjacent to the own station on the ad hoc multi-hop communication network when a failure occurring in an upstream section on the specific communication path is detected or identified. Then, the result of the reconfirmation is notified to the specific wireless node.
In other words, the reconfirmation of the adjacent radio node that should be performed because a failure has occurred in the upstream section on the specific communication path is achieved without the intervention of a specific radio node above the radio node device according to the present invention. The result of such reconfirmation is reflected in the configuration of the ad hoc multi-hop communication network formed by the specific wireless node.

In the invention according to claim 2 , the communication means is arranged under a specific radio node forming an ad hoc multi-hop communication network, and serves as a relay terminal or a terminal of a specific communication path formed by the specific radio node. Operate. The notification means includes an upstream wireless node located on the upstream side of the upstream section on the specific communication path when a failure occurring in the upstream section on the specific communication path is detected or identified. Information necessary for reconfirmation of adjacent wireless nodes that can be adjacent on the ad hoc multi-hop communication network and reconfiguration of a communication path based on the result of the reconfirmation is notified to the specific wireless node.
That is, a failure that occurs in an upstream section on a specific communication path is dealt with under the initiative of the specific radio node under the control of the specific radio node (related to the present invention). Including wireless node devices).

In the invention according to claim 3 , the communication means is arranged under a specific radio node forming an ad hoc multi-hop communication network, and serves as a relay terminal or a terminal of a specific communication path formed by the specific radio node. Operate. The notification means is configured to notify an upstream wireless node located upstream of the upstream section on the specific communication path when a failure occurring in the upstream section on the specific communication path is detected or identified. Necessary to reconfirm neighboring wireless nodes that can be adjacent to the upstream wireless node on the ad hoc multi-hop communication network, and to reconfigure the communication path based on the result of the reconfirmation to the specific wireless node Notify information.
That is, the reconfirmation of the adjacent radio node that should be performed because a failure has occurred in the upstream section on the specific communication path is performed by linking the upstream radio node and the specific radio node that are above the radio node device according to the present invention. In addition, the result of such reconfirmation can be reflected on the configuration of the ad hoc multihop communication network formed by the specific wireless node.

In the invention according to claim 4 , the communication control means reconfigures a communication path having the plurality of wireless nodes as relay terminals or terminals when any of the subordinate wireless nodes performs communication. To form an ad hoc multi-hop communication network. The communication unit communicates with the plurality of wireless nodes via the communication path. When the communication control means is notified of an error occurring in any section of the communication path from an upstream wireless node arranged upstream of the section among the plurality of wireless nodes, the communication control means Then, the downstream wireless node arranged on the downstream side of the section is requested to reconfirm the adjacent wireless node of the downstream wireless node, and the communication path is reconfigured by reflecting the result of the reconfirmation.
In the wireless node device to which the present invention is applied, when a failure occurs in any section on the communication path, the failure is notified by an upstream wireless node arranged on the upstream side of the section.

In the invention according to claim 5 , the communication control means sets a normal radio node among the plurality of radio nodes as a relay terminal or a terminal when any of the subordinate radio nodes performs communication. By reconfiguring the communication path, an ad hoc multi-hop communication network is formed. The communication unit communicates with the plurality of wireless nodes via the communication path. The communication control means is notified of a failure occurring in any section of the communication path from an upstream wireless node arranged upstream of the section among the plurality of wireless nodes, and the ad hoc multi-hop communication. When the number of wireless nodes adjacent to the upstream wireless node on the network falls below a predetermined threshold, the adjacent wireless of the downstream wireless node is connected to the downstream wireless node arranged on the downstream side of the section on the communication path. Requesting node reconfirmation and reconfiguring the communication path reflecting the result of the reconfirmation.
That is, in any section on the communication path, in the wireless node in which the wireless node excluded as the cause of the failure that occurred corresponds to the adjacent node, the number of adjacent nodes of the wireless node may be excessively reduced. Avoided.

As described above, according to the present invention, it is avoided that the remaining amount of the battery is rapidly reduced due to the specific wireless node, and the remaining amounts of the batteries of the plurality of wireless nodes are averaged.
According to the present invention, in the reconfiguration of the communication path performed by the communication control means, it is possible to avoid the occurrence of a failure and the spread due to the presence of a wireless node that is not operating normally in any communication path. Become.
According to the present invention, a communication path applicable to communication according to an event occurring in a wireless node is secured.

According to the present invention, a stable communication path can be secured.
According to the present invention, a communication path with high transmission quality can be secured stably.
According to the present invention, a good communication path is stably maintained over a longer period than in the conventional example without increasing the load on each wireless node or reducing the overall communication speed.

According to the present invention, even if a specific communication path is not reconfigured, it is possible to identify a fault that has occurred in a specific section of the specific communication path and to take a measure for the fault.
According to the present invention, the amount of processing to be ensured in a specific wireless node in order to cope with a failure occurring in a section on a specific communication path is a plurality of radios arranged under the specific wireless node. Mitigated under load balancing by node equipment.

According to the present invention, the amount of processing to be ensured in a specific wireless node in order to cope with a failure occurring in a section on a specific communication path is a plurality of radios arranged under the specific wireless node. Mitigated under functional distribution with node equipment.
According to the present invention, the amount of processing to be ensured in a specific wireless node in order to cope with a failure occurring in a section on a specific communication path is a plurality of radios arranged under the specific wireless node. Mitigated under load balancing by node equipment.

According to the present invention, even if the communication path is not reconfigured, it is possible to identify a fault that has occurred in a specific section of the communication path and take measures against the fault.
According to the present invention, it is possible to maintain high flexibility and transmission efficiency of an ad hoc multi-hop communication network.

  Therefore, in the ad hoc multi-hop communication network to which the present invention is applied, the replacement frequency of the battery that drives each wireless node is reduced, and the transmission speed and transmission quality are maintained high, and maintainability and reliability are also maintained. Is improved overall.

It is a figure which shows the 1st Embodiment of this invention. It is an operation | movement flowchart of the gateway in the 1st Embodiment of this invention. It is a figure explaining the operation | movement of the 1st Embodiment of this invention. It is a figure which shows the structure of 14N of adjacent node lists. It is a figure which shows the structure of the adjacent node list | wrist 13GW. It is a figure which shows the difference in the frequency | count of transmission of each node, and the frequency | count of reception. It is a figure which shows the structure of a node management table. It is a figure which shows the structure of a path | route connection list. It is a figure which shows the structure of a measurement order list | wrist. It is a figure which shows the 2nd and 3rd embodiment of this invention. It is a figure explaining operation | movement of the 2nd and 3rd embodiment of this invention. It is an operation | movement flowchart of the gateway in the 2nd Embodiment of this invention. It is a figure explaining the operation | movement of the 2nd Embodiment of this invention. It is a figure which shows the structural example of a notification packet. It is a figure which shows the structural example of a link route list. It is an operation | movement flowchart of the gateway in the 3rd Embodiment of this invention. It is a figure which shows cooperation of each part in the 3rd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing a first embodiment of the present invention.
In the figure, a plurality of access points (AP) 11-1 to 11-n are arranged on the link 10. Among these access points 11-1 to 11-n, the host system 12 is connected to the access point 11-1. Further, among the access points 11-1 to 11-n, the gateway 13-C is connected to the access point 11-C. Nodes 14-A1 to 14-A4, 14-B1 to 14-B7, 14-C1 to 14-C7, 14-D1, and 14-D2 are arranged under the gateway 13-C. The driving power of these nodes 14-A1 to 14-A4, 14-B-1 to 14-B7, 14-C1 to 14-C7, 14-D1, and 14-D2 is supplied from individually provided batteries (not shown). )).

The driving power for the gateway 13-C is supplied from a commercial power source or the like.
Further, among the access points 11-1 to 11-n, access points other than the access point 11-C are connected to one gateway (not shown), and a plurality of nodes are individually controlled under these gateways. Is placed.

Hereinafter, the operation of the present embodiment will be described with respect to the gateway 13-C and the nodes 14-A1 to 14-A4, 14-B1 to 14-B7, 14-C1 to 14-C7, 14D-1, and 14-D2. A description will be given focusing on an ad hoc multi-hop communication network composed of:
Accordingly, gateways other than the gateway 13-C and nodes other than the nodes 14-A1 to 14-A4, 14-B1 to 14-B7, 14-C1 to 14-C7, 14-D1, and 14-D2 The illustration and description of the configuration are omitted.

[First Embodiment]
FIG. 2 is an operation flowchart of the gateway according to the first embodiment of the present invention.
FIG. 3 is a diagram for explaining the operation of the first embodiment of the present invention.
The operation of the first embodiment of the present invention will be described below with reference to FIGS.

  In the following, for items common to the nodes 14-A1 to 14-A4, 14-B1 to 14-B7, 14-C1 to 14-C7, 14-D1, and 14-D2, the subscripts “A1” to It describes using the code | symbol "14" which does not contain "A4", "B1"-"B7", "C1"-"C7", "D1", and "D2".

  In addition, elements that are added or defined as such common items are indicated by a single letter “N” to be described later at the end of the symbol “14”.

In the main memory of the node 14, as shown in FIG. 4, an adjacent node list 14 </ b> N composed of a row of records including the following three items is arranged.
(1) An identifier of an individual node adjacent to the node 14 on some communication path (hereinafter referred to as “adjacent node identifier”).
(2) The RSSI (Received) of the wireless packet received from the corresponding “adjacent node”
Signal Strength Indication value
(3) LQI (Link
Quality Indication Value In addition, a “route connection list (not shown)” that is referred to only by the node 14 is individually arranged in the main memory of the node 14.

  In the following, for the “adjacent node identifier”, the subscripts (“A1” to “A4”, “B1” to “B7”, “C1”, which are added to the code “14” of the corresponding node are described below. ”To“ C7 ”,“ D1 ”, or“ D2 ”). The node identifier of the gateway 13-C is expressed as “0”.

  Further, as shown in FIG. 5, the main memory of the gateway 13-C includes nodes 14-A1 to 14-A4, 14-B1 to 14-B7, 14-C1 to 14-C7, 14 arranged under the subordinate. -D1, 14-D2 and the gateway 13-C are arranged individually, and the adjacent node list 13GW composed of a plurality of blocks having the same configuration as the above-described adjacent node list 14N is arranged. .

In the process of starting the present embodiment or starting steady operation, the respective units cooperate to perform the following processing.
(1) Processing for determining the contents of the adjacent node list 14N
(2) Processing for determining the contents of the adjacent node list 13GW
(3) Communication path formation processing

Hereinafter, these processes will be described in order.
[Process of confirming the contents of the adjacent node list 14N]
At the time of start-up, existing nodes (for example, symbols “14-A1” to “14-A4”, “14-B1” to “14-B7”, “14-C1” to “14”) are subordinate to the gateway 13-C. 14-C7 "," 14-D1 ", and nodes to which" 14-D2 "are attached) are formed as communication paths that serve as relay nodes or terminal nodes. Note that such a communication path is determined by the contents of the adjacent node lists 13GW and 14N held by the gateway 13-C and the node 14 and a “path connection list” described later.

  When a new node (hereinafter denoted by reference numeral “14-T1”) is added at the time of start-up or after start-up, each unit is linked by the following procedure, thereby the adjacent node list 14N. Update the contents of.

  The node 14-T1 performs a predetermined initialization process when the power is turned on (FIG. 3 (1)). In the initialization process, the node 14-T1 generates a random number based on an initial address set at the time of factory shipment, and a packet including the random number as a node identifier (for example, the nodes 14-A1 to 14-). A4, 14-B1 to 14-B7, 14-C1 to 14-C7, 14-D1, and 14-D2) are broadcasted (FIG. 3 (2)). Hereinafter, of these nodes, a node that responds to the packet is referred to as an “adjacent node”.

  When the adjacent node 14 receives the broadcasted packet, if the RSSI value of the packet exceeds a predetermined threshold, the adjacent node 14 obtains the LQI value of the corresponding packet. When there is a path connection list that has been used most recently at this time, the adjacent node 14 is also referred to as the above-mentioned RSSI value and LQI value (hereinafter, these sets are simply referred to as “response”). Is transmitted to the node 14-T1 (FIG. 3 (3)). However, if there is no such route connection list, the adjacent node 14 transmits only the RSSI value and the LQI value (hereinafter also referred to as “response”) to the node 14-T1 (FIG. 3). (3)).

  The node 14-T1 obtains an RSSI value and an LQI value of the corresponding response with respect to a node that is a transmission source of the response received within the predetermined time after the broadcast, and node identifiers in descending order of these RSSI values, The combination of the RSSI value and the LQI value is registered in the adjacent node list 14N (FIG. 3 (4)). The number of nodes registered in the adjacent node list 14N is set to a preset upper limit value (= max).

Therefore, the node 14 arranged under the gateway 13-C can appropriately identify other nodes that can communicate based on the contents of the adjacent node list 14N.
In addition, when the above-mentioned broadcast is performed almost simultaneously by a plurality of nodes, one of the priority is given priority under a predetermined communication control, and a broadcast that has not been completed normally has a predetermined time elapsed by the source node. Will be retried after.

[Process of confirming contents of adjacent node list 13GW]
When the content of the adjacent node list 14N is determined in this way, the node 14-T1 refers to any path connection list of the adjacent node that is the transmission source of the received “response”, for example, the RSSI value is the maximum. The contents are transferred to the gateway 13-C via a certain adjacent node and the uplink of the communication path that is determined by the contents of the existing path connection list and that the adjacent node intervenes as a relay terminal or terminal. (Fig. 3 (5)).
In the third embodiment to be described later, a packet forwarded to the gateway 13-C and including such content is referred to as a “network participation request” packet.

Note that such an uplink link may be, for example, an uplink link of a communication path with the minimum number of hops reaching the gateway 13-C.
The gateway 13-C adds the contents of the adjacent node list transferred by the node 14-T1 to the adjacent node list 13GW (step S1, FIG. 3 (6) in FIG. 2).

The gateway 13-C assigns a unique node identifier to the node 14-T1 and registers it in the adjacent node list 13GW (step S2 in FIG. 2, FIG. 3 (7)). Further, the gateway 13-C transmits the node identifier registered in this way (hereinafter referred to as “official node identifier”) to the node 14-T1 (step S3 in FIG. 2, FIG. 3 (8)). .
The node 14-T1 reflects the official node identifier in the route connection list and the adjacent node list 14N (FIG. 3 (9)).
The route connection list 20 may be prioritized in ascending order (or descending order) of the number of hops.
Here, a packet including a formal node identifier and transmitted to the node 14-T1 as described above is referred to as a “network participation request response” packet in a third embodiment to be described later.

  In addition, the number of adjacent nodes that can be registered in the gateway 13-C and the node 14 is set to a value (for example, “100” and “10”, respectively) according to the scale of the network and the operation status. Is done. Accordingly, it is possible to appropriately terminate the repetition of communication control performed corresponding to each adjacent node and to ensure high responsiveness and service quality.

  The gateway 13-C performs delivery confirmation based on a predetermined communication procedure with “a node that is arranged at one end of all communication paths and is located at the end of any of these communication paths”.

  For example, the gateway 13-C cooperates with all the nodes 14-A1 to 14-A4, 14-B1 to 14-B7, 14-C1 to 14-C7, 14-D1, and 14-D2 to observe information (battery 1) is collected, the “observation information collection request” and the “response” in response to the request are transmitted via all the communication paths A to H indicated by the one-dot chain line in FIG. Is called.

  Note that the number of transmissions and receptions of each node in the process of collecting such observation information is, for example, all of the nodes 14-A1 to 14-A4, 14-B1 to 14-B7, 14-C1 to 14-C7, 14- When collection of observation information by D1 and 14-D2 is performed once, the result is as shown in FIG.

Further, as shown in FIG. 7, the gateway 13-C includes the subordinate nodes 14-A1 to 14-A4, 14-B1 to 14-B7, 14-C1 to 14-C7, 14-D1, and 14-D2. It has a node management table 13M-C composed of records including the following items corresponding to each.
(a) Node identifier
(b) Number of communications
(c) Connected flag
(d) Measurement control target
(e) Battery terminal voltage
(f) Number of errors

  Here, the “number of communications” is the sum of the number of transmissions (or the number of receptions) described above. The value of the “connected flag” is initialized to “0” at the start of the reconfiguration of the communication path, and the value is set to “1” in a state where the processing necessary for the reconfiguration is completed for the corresponding node. It is binary information. “Measurement control target” is an identifier of an item to be measured or controlled by the corresponding node. The “measurement control target” includes, for example, information indicating a type such as “simultaneous” or “individual” which is a form of measurement or observation. The “battery terminal voltage” is a terminal voltage of the battery provided in the node 14, and a value notified from the corresponding node when it falls below a predetermined threshold is written and held by the gateway 13 -C. The “number of errors” is a count value for counting the frequency of occurrence of errors (for example, delivery confirmation or missing response) for each node identified by the gateway 13-C based on a predetermined procedure or standard.

[Communication path formation processing]
The gateway 13-C cooperates with the subordinate nodes 14-A1 to 14-A4, 14-B1 to 14-B7, 14-C1 to 14-C7, 14-D1, and 14-D2 based on the following procedure. By forming a communication path, an ad hoc multi-hop communication network in which these nodes are relay nodes or terminal nodes is formed.

  The gateway 13-C sends a communication request (for example, the nodes 14-A1 to 14-A4, 14-B1 to 14-B7, 14-C1 to 14-C7) from the host system 12 via the link 10 and the access point 11-C. , 14-D1, and 14-D2), the route connection list 20 shown in FIG. 8 and the measurement order list 21 shown in FIG. 9 are regenerated.

  Here, in the path connection list 20, as shown in FIG. 8, the “node identifier” and the “upper link identifier” indicating the communication path in which the node indicated by the “node identifier” intervenes as a relay node or a terminal node. Are paired and registered for each number of hops.

  Further, the route connection list 20 includes a gateway as a measurement order list 21 in which a pair of the above “node identifier” and “upper link identifier” is arranged in blocks in descending order of the number of hops as shown in FIG. It is placed in 13-C main memory and referred to as appropriate.

  The gateway 13-C always counts the number of times of communication (number of times of transmission / reception) of each node and holds it in the “number of times of communication” field in the corresponding record of the node management table 13M-C.

  The node 14 monitors the terminal voltage of the battery described above (FIG. 3 (10)), and sends the terminal voltage to the gateway 13-C via the existing communication path based on a predetermined communication procedure. To be notified. The gateway 13-C holds the terminal voltage in the “battery terminal voltage” field in the corresponding record of the node management table 13M-C (FIG. 3 (11)).

  Note that the function distribution and the load distribution in the process in which such terminal voltage is notified from each node to the gateway 13-C allows the gateway 13-C to monitor the terminal voltage with a desired frequency and accuracy. Anything can be used.

The gateway 13-C performs the following processing in the process of reconfiguring the above-described route connection list 20 (FIG. 3 (12)).
(1) The values in the “connected” field of all records in the node management table 13M-C are initialized to “0” (step S4 in FIG. 2).
(2) Among the “adjacent nodes of the gateway 13-C” registered in the adjacent node list 13GW, the value of the “connected” field registered in the node management table 13M-C is “0” and the adjacent nodes Are registered in the path connection list 20 as nodes corresponding to the number of hops “1” (step S5 in FIG. 2).

(3) The value of the “connected” field on the node management table 13M-C corresponding to these registered nodes is set to “1” (step S6 in FIG. 2).
(4) For the number of hops h equal to or greater than “2”, the following processes (4-1) to (4-3) are repeated in ascending order of the number of hops h.
(4-1) Of the “adjacent nodes of the gateway 13-C” registered in the adjacent node list 13GW, the value of the “connected” field registered in the node management table 13M-C is “0”, and A node having a small number of communications and a large battery terminal voltage is preferentially selected.
(4-2) The node thus selected is registered in the route connection list 20 as a node corresponding to the number of hops (h + 1) (step S7 in FIG. 2).
(4-3) The value of the “connected” field on the node management table 13M-C corresponding to these registered nodes is set to “1” (step S8 in FIG. 2).
After the reconfiguration of the communication path is completed in this way, for example, in order to complete the measurement control given from the host device 12 via the link 10 and the access point 11-C, the gateway 13-C and the node 14 Work together based on the following policy.

[Policy of processing performed by gateway 13-C]
(1) A node with a large number of hops and a small number of communications is given priority for measurement control, and a related route connection list is sent to all of the target nodes.
(2) The node subject to measurement control is appropriately identified, and “communication count” and “error count” are counted up for the records on the node management table 13M-C corresponding to the corresponding node.

(3) Based on the number of such errors, a communication abnormality (not only a failure that occurred in the corresponding node, but also a failure in a wireless transmission (propagation) path connected to the downstream side of that node) is identified, and After the node in which the communication abnormality has occurred is excluded from the adjacent node list 13GW, the path connection list 20 is reconfigured.
(4) Exclude from the system configuration nodes that communication anomalies are not resolved even if the above processes (1) to (3) are repeated.

[Policy of processing performed by the node 14]
(1) With reference to the path connection list 20 delivered from the gateway 13-C during measurement control, a predetermined number (for example, “3”) of communication paths indicated by the path connection list 20 is held. Note that the communication path held in this manner is not necessarily the latest communication path. For example, the communication path with a small number of hops, the operation status of each unit, the transmission quality of the wireless section, the congestion in each transmission section, and the like It is possible to select flexibly based on environmental conditions.
(2) The held communication path is applied to notification of an event or the like to a higher level such as the gateway 13-C.

  That is, a communication path in an ad hoc multi-hop communication network is reconfigured in response to the generation of a communication request such as measurement control, and in the process of reconfiguration, a node having a high frequency of communication performed in advance and a battery Nodes with a small remaining amount are assigned as “terminal nodes” or “relay nodes with few communication paths to be relayed”.

  Therefore, according to the present embodiment, a large disparity in the power consumption of the nodes is less likely to occur, so the frequency with which the battery is replaced for any node is greatly reduced.

[Second Embodiment]
FIG. 10 is a diagram showing the second and third embodiments of the present invention.
In the figure, nodes 14-A1, 14-A2, 14-B1, 14-B2, 14-C1, 14-D1, and 14-E1 are arranged under the gateway 13-C. Here, it is assumed that the following two communication paths P and Q are formed as shown by a one-dot chain line in FIG.
(a) Communication path P: gateway 13-C to nodes 14-A1, 14-B1
(b) Communication path Q: gateway 13-C to nodes 14-A2, 14-B2, 14-C1, 14-D1, 14-E1

FIG. 11 is a diagram for explaining the operation of the second and third embodiments of the present invention.
FIG. 12 is an operational flowchart of the gateway in the second embodiment of the present invention.
FIG. 13 is a diagram for explaining the operation of the second embodiment of the present invention.

The operation of the second embodiment of the present invention will be described below with reference to FIGS.
As shown in FIG. 11A by “x” marks, the feature of the present embodiment is that a communication error that occurs on the communication path Q is detected and a communication path is reconfigured according to the communication error. is there.

The communication paths P and Q are formed under the initiative of the gateway 13-C as in the first embodiment described above.
When the above-described measurement control request is generated, the gateway 13-C transmits a predetermined packet (hereinafter referred to as “request packet”) including information relating to the measurement control, as indicated by a dotted line in FIG. The data is sent to P and Q (step S1 in FIG. 12). When the destination of such a request packet is not the node 14 itself, the node 14 transfers this packet to an adjacent node located downstream of the corresponding communication path.

  Further, when the destination of the corresponding request packet is the node itself, the node 14 performs processing adapted to the contents of this packet. Further, the node 14 sends a packet indicating the result of this processing (hereinafter referred to as “response packet”) to an adjacent node located upstream of the corresponding communication path.

  If the destination of the received “response packet” is not the adjacent node 14 itself, the adjacent node 14 positioned on the upstream side transmits this “response packet” to the adjacent node positioned on the upstream side of the corresponding communication path. ".

  By the way, in the state where a failure occurs between the nodes 14-B2 to 14-C1 on the communication path Q as indicated by “x” in FIG. 11A, the node 14-B2 is connected to the node 14-C1. Cannot receive "response packet". It should be noted that the state in which the “response packet” cannot be received in this manner may be caused by a failure in both or any one of the nodes 14-B2 and 14-C1. However, in this embodiment, even when such a failure occurs in the nodes 14-B2 and 14-C1, securing of the communication path is achieved based on the reconfiguration of the communication path described later.

In such a case, the node 14-B2 detects the communication error by performing the following processing (FIG. 13 (1)).
(1) By referring to the above-described route connection list 20 (or measurement order list 21), the remaining number of hops H reaching the node 14-E1 corresponding to the terminal node of the corresponding communication route is acquired.
(2) Start counting the time Tm that has passed since the request packet was transmitted.
(3) Each time the time Tm is updated, it is determined whether or not the following inequality is satisfied for the time T described later, and the communication error is identified when the inequality is not satisfied.
Tm ≦ H ・ T

Here, T is expressed by the following equation with respect to the average value tk of the lengths of the “request packet” and “response packet” on the time axis and the margin α that can absorb the variation of the value tk. Indicated.
T = 2 · tk + α

  Further, when identifying the communication error, the node 14-B2 replaces the “notification packet” with the node 14-A2 adjacent to the upstream side instead of the “response packet” that should be originally received from the downstream node 14-C1. (Including the identification information of the section in which this communication error has occurred) is transmitted (FIG. 13 (2)).

  This “notification packet” is delivered to the gateway 13-C under the relay process performed by the node 14-A2 (FIG. 13 (3)).

  When the gateway 13-C does not receive the “notification packet” or fails to receive the “response packet” within a predetermined time (FIG. 13 (4)), the gateway 13-C has a predetermined number of times. The above-described transmission of the “request packet” is repeated (step S2 in FIG. 12, FIG. 13 (5)).

  When the gateway 13-C cannot receive the “response packet” for any of the “request packets” repeated in this way within a predetermined time, the following processing (1) to (4) )I do.

(1) When the above-described “notification packet” can be received, the nodes 14-B2 and 14-C1 respectively located at both ends of the section indicated by the identification information included in the “notification packet” are specified (FIG. 12 step S3, FIG. 13 (6)). Hereinafter, the node 14-B2 is referred to as an “upstream node” and the node 14-C1 is referred to as a “downstream node”.
(2) Identify the corresponding communication path Q as “communication path in which a communication error has occurred”.

(3) The upstream node 14-B2 and the downstream nodes 14-C1, 14-D1, 14-E1 are excluded from the communication path Q (step S5 in FIG. 12, FIG. 13 (8)).
(4) As shown in FIG. 11B, the two communication paths P and R that are communication paths other than the communication path Q and in which no communication error has occurred at this time are reconfigured as follows. . The downstream node 14-C1 is incorporated at the end of the communication path P, and the nodes 14-D1, 14-E1 on the downstream side of the downstream node 14-C1 are incorporated at the end of the communication path R (FIG. 12, step S6, FIG. 13 ( 9)). Note that the communication paths and locations where these nodes 14-C1, 14-D1, and 14-E1 are incorporated are not limited to the end as long as they are existing communication paths in which no communication error occurs, and normal communication paths. As a relay node.

  The nodes 14-A1 and 14-B1 are shared as relay nodes for the communication paths P and R.

  However, the section composed of the downstream node 14-C1 and the nodes 14-D1 and 14-E1 downstream from the downstream node is a “different communication path in which no node is included as a common relay node”. May be incorporated.

  Further, the gateway 13-C is similar in the case where a communication error occurs due to a failure of the nodes 14-B2, 14-C1 or a failure in a transmission section between these nodes 14-B2, 14-C1. By performing this process, the corresponding communication error is recovered.

  That is, when a communication error occurs in the communication path, the upstream node and the downstream node of the transmission section in which the communication error has occurred are incorporated into different normal communication paths under the reconfiguration of the other communication path. A transmission section downstream from the downstream node is also incorporated into some normal communication path.

  Therefore, according to the present embodiment, when a failure occurs in any of the nodes arranged under the gateway 13-C, a communication error due to the failure is recovered, and transmission quality, transmission efficiency, and reliability are improved. Highly maintained.

In the present embodiment, the communication error may not be identified based on the above-described inequality. If the identification of the communication error is realized with high accuracy, for example, the conditions (1) to (1) to be listed below are listed. It may be identified by either success or failure of (4).
(1) The frequency or number of times that "response packets" were not successfully received exceeded the specified upper limit.
(2) The frequency or number of times that the transmission quality of the “response packet” (evaluated based on RSSI or LQI) falls below a predetermined threshold exceeds the specified upper limit.
(3) A CRC error occurred in the physical layer.
(4) An abnormal state was identified based on the communication procedure in the desired communication layer.

  In addition, for example, when the frequency or number of times described in (1) and (2) above increases, the priority of the “communication path including the corresponding section” is set low. And may be identified when the priority falls below a specified lower limit. Such a priority may be used as a priority at which the corresponding communication path is used for actual communication.

  Further, in the present embodiment, the lengths tk of “request packet” and “response packet” are calculated as average values, but in the present invention, such a length tk is set to an appropriate value for each section. Thus, the present invention may be applied to a variable-length packet transmission system.

  In the present embodiment, the above-described margin α is set as an average value of the sum total common to the transmission sections of the corresponding communication path. For example, for each of these transmission sections, the transmission amount and the node The difference in the responsiveness (or the degree of overload) may be set to a value that substantially reflects it.

Furthermore, in the present embodiment, the “notification packet” includes “identification information of a section in which a communication error has occurred”. However, such a “notification packet” may include the following fields, for example, as shown in the shaded portion of FIG.
(1) "Network address" field where a unique address assigned to the nearest destination node on the communication path is placed
(2) “Time-out check” field in which binary information indicated by logical values “1” and “0” is arranged to indicate whether or not a communication error is detected due to a timeout based on the above-described inequality.
(3) Timeout node field in which the unique address assigned to the node that detected the timeout is placed
(4) "Number of link nodes" field in which the number of nodes connected via a multi-hop communication path is placed
(5) Current “link node No.” field in which the unique number assigned to the corresponding communication path is placed
(6) “Link direction” field in which binary information (= 1/0) indicating which of “uplink” and “downlink” corresponds to the corresponding communication path is arranged
(7) Link route field in which the address column of adjacent nodes on the communication path is placed
(8) Different information (for example, requests related to measurement / control, each node, etc.) that are handed over to each other between the gateway 13-C and the node 14 and that correspond to the function and configuration of the system to which this embodiment is applied. "Transmission information" field in which the event that occurred) is placed

  The configuration of the “notification packet” is not limited to such a configuration, and is substantially the same as that of the present embodiment under the configuration of a communication path that can be actually formed or a communication path that can be reconfigured. 14 is covered, and the information necessary for specifying the section in which the communication error has occurred is covered, the shaded portion in FIG. 14 may be configured as any combination of information.

Further, in this embodiment, when the node 14-B2 identifies a communication error, the node 14-B2 identifies the end of the communication error in place of the “response packet” that should be received from the downstream node 14-C1. A “notification packet” including information is sent to the adjacent node 14-A2 on the upstream side.
However, the content of such a “notification packet” is generated under the processing activated in response to the “request packet” received by the node 14-B2 first, and information to be sent to the node 14-A2 is transmitted. In some cases, the information may be packed in a predetermined field of “response packet” including the information and transmitted.

[Third Embodiment]
The hardware configuration of the present embodiment is as shown in FIG.

In the present embodiment, as shown in FIG. 15, the node 14 is a sequence of records corresponding to individual communication paths in which the node 14 is incorporated as a relay node or a terminal node. A link route list 14LL in which “a column of addresses of nodes arranged adjacently on the corresponding communication path” is registered is arranged.
The contents of each record included in such a link route list 14LL correspond to individual communication routes formed under the initiative of the gateway 13-C and configured by incorporating the corresponding node 14. Although any of the communication paths is set, the node 14 that has detected (identified) that transmission of any packet in the direction of the gateway 13-C (upstream side) cannot be normally completed is promptly established as an alternative communication path. Referenced for identification.
Further, the nodes 14-A1 to 14-A4, 14-B1 to 14-B7, 14-C1 to 14-C7, 14-D1 are included in the adjacent node list 13GW arranged in the main memory of the gateway 13-C. , 14-D2 and gateway 13-C are individually associated with a plurality of blocks, as indicated by dotted lines in FIG. Is done.

Note that the priorities included in these adjacent node lists 14N and 13GW are set to, for example, “5” as an initial value for any node, and are updated as appropriate based on the processing procedure described later.
These priorities are appropriately referred to as criteria for selecting nodes (or communication paths) to be preferentially applied when configuring (connecting) communication paths according to communication requests such as measurement control.

FIG. 16 is an operational flowchart of the gateway according to the third embodiment of the present invention.
FIG. 17 is a diagram for explaining the operation of the third embodiment of the present invention.

Hereinafter, the operation of the third embodiment of the present invention will be described with reference to FIGS. 8 to 11, 16 and 17. In the following, it is assumed that the following two communication paths P and Q are formed, as in the second embodiment described above.
(a) Communication path P: gateway 13-C to nodes 14-A1, 14-B1
(b) Communication path Q: gateway 13-C to nodes 14-A2, 14-B2, 14-C1, 14-D1, 14-E1
The feature of the present embodiment is that it is formed in a specific section (formed between the node 14-B2 and the node 14-C1) on the communication path Q, as indicated by “x” in FIG. When a communication error occurs repeatedly, the procedure of reconfiguring the communication path is performed by linking these nodes 14-B2, 14-C1 and the gateway 13-C. Such a repeated communication error occurs because, for example, any of the shape, size, or position of a tree / moving body or the like interposed in the propagation path of the section changes.

The communication paths P and Q are formed under the initiative of the gateway 13-C as in the first and second embodiments described above.
When a measurement control request is generated, the gateway 13-C sends a “request packet” including information related to the measurement control to the communication paths P and Q, as in the second embodiment described above (FIG. 16). Step S1). When the destination of such a request packet is not the node 14 itself, the node 14 transfers this packet to an adjacent node located downstream of the corresponding communication path.

  Further, when the destination of the corresponding request packet is the node itself, the node 14 performs processing adapted to the content of this packet. Further, the node 14 sends a “response packet” indicating the result of this processing to an adjacent node located upstream of the corresponding communication path.

  If the destination of the received “response packet” is not the adjacent node 14 itself, the adjacent node 14 positioned on the upstream side transmits this “response packet” to the adjacent node positioned on the upstream side of the corresponding communication path. ".

  By the way, as indicated by “x” in FIG. 11A, in a state where a communication error occurs in a section between the nodes 14-B2 and 14-C1 on the communication path Q, the node 14-B2 The “response packet” transmitted from the node 14-C1 cannot be received.

In such a case, the node 14-B2 detects the communication error by performing the same processing as in the second embodiment described above (FIG. 17 (a)).
Further, when the node 14-B2 identifies this communication error, the node 14-B2 replaces the “response packet” that should be originally received from the downstream node 14-C1 with the “notification packet”. (Including the identification information of the section in which this communication error has occurred) is transmitted (FIG. 17 (b)).

  This “notification packet” is delivered to the gateway 13-C under the relay process performed by the node 14-A2 (FIG. 17 (c)).

  When the gateway 13-C does not receive the “notification packet” and fails to receive the “response packet” within a predetermined time (FIG. 17 (d)), the gateway 13-C performs the following processing. .

(1) The priority included in the record (all) corresponding to the node to be the transmission source of the “response packet” among the records included in the adjacent node list 13GW is decremented (step S2 in FIG. 16).

(2) If the priority updated under such decrement is, for example, “1” or more, the above-described transmission of the “request packet” is repeated (step S3 in FIG. 16 and FIG. 17 (e)). ). Further, when none of the “response packets” for the “request packet” repeated in this way can be received within a predetermined time, the following as in the second embodiment described above: Processes (2-1) to (2-3) are performed. Hereinafter, the processes described in the above (2) and the following (2-1) to (2-3) are referred to as “retry processing based on priority”.

(2-1) When the above-mentioned “notification packet” is received, the nodes 14-B2 and 14-C1 located at both ends of the section indicated by the identification information included in the “notification packet” are specified. (FIG. 16, step S4, FIG. 17 (f)). Hereinafter, the node 14-B2 is referred to as an “upstream node” and the node 14-C1 is referred to as a “downstream node”.
(2-2) The corresponding communication path Q is identified as “communication path in which a communication error has occurred” (step S5 in FIG. 16).
(2-3) The nodes 14-C1, 14-D1, and 14-E1 on the downstream side are excluded from the communication path Q, and the communication path is reconfigured via these nodes 14-C1, 14-D1, and 14-E1. For example, as shown in FIG. 11B, the node 14-C1 is incorporated at the end of the communication path P (downstream of the node 14-B1), and the nodes 14-D1, 14-E1 are The node 13-C is incorporated into a new communication path R in which these nodes 14-D1 and 14-E1 are arranged downstream of the nodes 14-A1 and 14-B1 (step S6 in FIG. 16, FIG. 17 (h)).

(3) However, the record of the adjacent node included in the adjacent node list 13GW corresponding to the node for which the updated priority is “0” is excluded (step S7 in FIG. 16, FIG. 17 (j)). After performing such processing, the following processing (3-1) to (3-3) is performed by referring to the adjacent node list 13GW.

(3-1) Blocks in which the number of records (corresponding to the adjacent nodes of the corresponding node) included in the adjacent node list 13GW corresponding to each node is equal to or less than a predetermined lower limit value Is specified (step S8 in FIG. 16).
(3-2) A node corresponding to this block (here, assumed to be node 14-C1) is identified (step S9 in FIG. 16).
(3-3) An “adjacent node search processing request” packet, which is an activation request for “adjacent node search processing” to be described later, is transmitted to the node 14-C1 (step S10 in FIG. 16, FIG. 17 (k)).

  Note that the communication path for transmitting this “neighboring node search processing request” packet to the node 14-C1 is allocated by, for example, the gateway 13-C reconfiguring the neighboring node list 13GW, or existing An effective communication path registered in the adjacent node list 13GW may be assigned.

  On the other hand, when the node 14-C1 identifies the “neighboring node search processing request” packet, for example, the processing in the first embodiment (FIG. 3 (2), (4), (5), (9)) and The same processing is performed, and the other nodes 14-A1, 14-A2, 14-B1, 14-B2, 14-D1, 14-E1 and the gateway 13-C are linked based on the processing procedure.

The processing performed by each unit under such linkage (hereinafter referred to as “neighboring node search processing”) is as described in the first embodiment described above except for the following points.
(1) The node 14-C1 operates as the node 14-T1 in the first embodiment.
(2) The nodes 14-A1, 14-A2, 14-B1, 14-B2, 14-D1, and 14-E1 operate as “nodes other than the node 14-T1” in the first embodiment.

  Therefore, the details of such “neighboring node search processing” are omitted here, and FIG. 17 for explaining the operation of this embodiment is shown in FIG. However, the processing performed in the same manner is indicated by the same numbers (2) to (9) as in FIG.

  That is, the number of adjacent nodes registered on the adjacent node list 13GW is equal to or less than a predetermined value because a communication error has occurred a predetermined number of times on the communication path or has occurred at a frequency exceeding an allowable limit. In response to the “neighboring node search processing request” packet issued by the gateway 13-C, the new node has a new “neighboring node list” indicating a communication path in which the node is incorporated as a relay node or a terminal node. Is envisioned.

  Therefore, even if communication errors occur sporadically or frequently occur in any section of the communication path, the nodes placed at one end of the section can be used effectively for normal functions and performance, Continue to be integrated into the appropriate communication path.

In the present embodiment, both the trigger for starting the “adjacent node search process” and the selection of the node 14-C1 that is the target of the “adjacent node search process” are the nodes 14- that detected the communication error. This is done not by B2 but by gateway 13-C.
However, such “neighboring node search processing” may be performed under the following function distribution, for example.

[First Functional Distribution Form]
The notification of the communication error to the gateway 13-C is performed not by the node 14-B2 that detected the communication error but by the nodes 14-A1 and 14-A2 adjacent to the upstream side of the node 14-B2.

[Second form of function distribution]
(1) The node 14-C1 detects a communication error as an event in which a response to a packet sent to the gateway 13-C cannot be normally received.
(2) The node 14-C1 notifies the communication error to “a downstream node adjacent to or interposed in the downstream side of the node 14-C1 (for example, the node 14-D2)”.
(3) When the downstream node identifies such a communication error, the downstream node performs the above-described “retry processing based on priority” and “adjacent node search processing”. Note that “retry processing based on priority” is performed by applying a normal alternative communication path in which a downstream node intervenes as a terminal node or a relay node at this time.

[Third form of function distribution]
(1) The node 14-C1 detects a communication error as an event in which a response to a packet sent to the gateway 13-C cannot be normally received.
(2) The node 14-C1 notifies the communication error to “a downstream node adjacent to or interposed in the downstream side of the node 14-C1 (for example, the node 14-D2)”.
(3) When the downstream node identifies such a communication error, the downstream node performs the aforementioned “retry processing based on priority”. Note that “retry processing based on priority” is performed by applying a normal alternative communication path in which a downstream node intervenes as a terminal node or a relay node at this time.
(4) However, as for the “adjacent node search process”, a process related to the “adjacent node search process” is performed from the downstream node to the gateway 13-C as performed under the initiative of the gateway 13-C. You are notified of the opportunity to start.

[Fourth function distribution form]
The processing performed by the node 14-C1 is different from the second or third functional distribution in that the processing is performed by any one of the nodes 14-D1 and 14-E1 disposed downstream by the node 14-C1. .

  In this embodiment and the second embodiment described above, the nodes 14-A1 and 14-B1 are shared as relay nodes for the communication paths P and R. However, the section composed of the downstream node 14-C1 and the nodes 14-D1 and 14-E1 downstream from the downstream node is a “different communication path in which no node is included as a common relay node”. May be incorporated.

  In each of the above-described embodiments, the adjacent node list 14N, the adjacent node list 13GW, the route connection list 20, the node management table 13M-C, the measurement order list 21, and the like are referred to by the gateway 13-C or the node 14, or The content and format of the information to be updated are not limited to those shown in the above-described embodiment, and may be anything within the scope of the present invention.

  The countermeasure when the above-described broadcasts occur at the same time is not limited to the one shown in the first embodiment described above, and appropriate exclusive control is desired between a plurality of nodes performing individual broadcasts. Any technique may be applied as long as it is realized with the accuracy and speed of the above.

The aforementioned delivery confirmation is not limited to that shown in the first embodiment described above, and may be realized based on any communication procedure.
The identification of the section where the communication error has occurred and the nodes located at both ends of the section are not limited to those shown in the second embodiment described above, and may be realized by any communication procedure or technique.

  The remaining amount of the battery that supplies the driving power for the node 14 may not be obtained based on the terminal voltage of the battery. For example, the current value at which the battery is actually supplied to the node 14 and the terminal of the battery It may be obtained based on the integral value of the product with the voltage, or may be obtained by applying any known technique.

  The installation position of the node 14 with respect to each communication path may not be determined based on both the battery terminal voltage and the number of communications, for example, based on either the battery terminal voltage or the number of communications. May be.

  The packet transmitted / received between the gateway 13-C and the node 14 may not be a fixed-length packet.

  The opportunity for reconfiguring the communication path is not limited to the time when the transmission of the “request packet” and the reception of the “response packet” are completed, but when the transmission / reception of a plurality of predetermined packets is completed, Alternatively, it may be a time point given in a predetermined cycle (frequency).

  The number of times of communication described above is for each node at the time when packet transmission / reception (transmission or reception) is performed when the size of the packet transmitted / received between the gateway 13-C and the node 14 is not constant. The integrated value may be substituted. Further, the number of times of communication may be the frequency or time rate of communication performed individually by the node 14.

  The present invention is not limited to a “wireless sensor network” in which measurement control is performed by the node 14 arranged under the gateway 13-C, and various ad hoc multi-hops are performed regardless of information to be transmitted. Applicable to communication networks.

  Of the nodes 14 arranged under the gateway 13-C, the basis for identifying the nodes that can communicate with each other is not limited to the RSSI value or LQI value described above. For example, these RSSI values or LQI values are not limited. Only one of the values may be used, or any alternative transmission quality.

  The wireless transmission between the gateway 13-C and the node 14 arranged under the gateway 13-C is based on any multiple access method, modulation method, and communication procedure as long as the above-described ad hoc multi-hop communication network is formed. It may be done.

  In each of the above-described embodiments, the linkage between the gateway 13-C and the node 14 is, as much as possible, “existing communication path” or “communication path in which a failure or the like has occurred, other than the section in which the failure or the like has occurred. This is done by exchanging predetermined information via “section”.

However, the communication path or transmission section may be replaced with any other communication path or transmission section as long as it can be used for such information exchange.
The present invention is not limited to the above-described embodiments, and various configurations can be made within the scope of the present invention, and any improvement may be applied to all or some of the components.

  Hereinafter, the inventions disclosed in the present application will be organized and listed in a format according to the descriptions in the “Claims” and “Means for Solving the Problems” columns.

[1] Communication that forms an ad hoc multi-hop communication network by reconfiguring a communication path using the plurality of wireless nodes as relay terminals or terminals when any of a plurality of subordinate wireless nodes performs communication. Control means;
A remaining amount monitoring means for monitoring a remaining amount of a battery that individually drives the plurality of wireless nodes;
The communication control means includes
The wireless node device characterized in that the number of intervening communication paths is set to be smaller for a wireless node having a smaller remaining battery capacity among the plurality of wireless nodes.
In the wireless node device having such a configuration, the communication control unit reconfigures a communication path using the plurality of wireless nodes as relay terminals or terminals when any of the subordinate wireless nodes performs communication. Thus, an ad hoc multi-hop communication network is formed. The remaining amount monitoring means monitors the remaining amount of the battery that individually drives the plurality of wireless nodes. The communication control unit sets the number of intervening communication paths to be smaller for a wireless node having a smaller remaining battery capacity among the plurality of wireless nodes.
That is, a wireless node that has as much remaining battery capacity as possible is assigned to a wireless node serving as a relay terminal for many communication paths.
Therefore, it is avoided that the remaining amount of the battery is rapidly reduced due to the specific wireless node, and the remaining amounts of the batteries of the plurality of wireless nodes are averaged.

[2] Communication that forms an ad hoc multi-hop communication network by reconfiguring a communication path having the plurality of wireless nodes as relay terminals or terminals when any of a plurality of subordinate wireless nodes performs communication. Control means;
Communication frequency monitoring means for monitoring the frequency with which the plurality of wireless nodes individually communicate,
The communication control means includes
A wireless node device characterized in that, among the plurality of wireless nodes, a wireless node having a higher frequency sets a smaller number of intervening communication paths.
In the wireless node device having such a configuration, the communication control unit reconfigures a communication path using the plurality of wireless nodes as relay terminals or terminals when any of the subordinate wireless nodes performs communication. Thus, an ad hoc multi-hop communication network is formed. The communication frequency monitoring means monitors the frequency with which the plurality of wireless nodes individually communicate. The communication control unit sets a smaller number of intervening communication paths as the frequency of the radio node is higher among the plurality of radio nodes.
In other words, as a result, a wireless node that has the lowest frequency of communication is allocated to a wireless node that is a relay terminal for many communication paths.
Therefore, it is avoided that the remaining amount of the battery is rapidly reduced due to the specific wireless node, and the remaining amounts of the batteries of the plurality of wireless nodes are averaged.

[3] In the wireless node device according to [1] or [2] above,
The communication control means includes
The wireless node device, wherein when any abnormality occurs in any of the plurality of wireless nodes, the communication path is reconfigured by excluding any of the wireless nodes.
In the wireless node device having such a configuration, the communication control unit excludes any one of the wireless nodes when the abnormality occurs in any one of the plurality of wireless nodes, and the communication path Reconfigure.
That is, the wireless node in which an abnormality has occurred is not incorporated in the communication path reconfigured by the communication control means.
Therefore, it is possible to avoid the occurrence of a failure and the spread due to the presence of a wireless node that is not operating normally in any communication path.

[4] In the wireless node device according to [1] or [2] above,
The communication control means includes
The wireless node device, wherein when any abnormality occurs in any of the plurality of wireless nodes, the communication path is reconfigured by removing any of the wireless nodes from a relay terminal.
In the wireless node device having such a configuration, the communication control unit excludes any of the wireless nodes from the relay terminal when an abnormality occurs in any of the plurality of wireless nodes. The communication path is reconfigured.
That is, the wireless node in which an abnormality has occurred is not incorporated as a relay terminal in the communication path reconfigured by the communication control means.
Therefore, it is possible to avoid the occurrence of a failure and the spread caused by incorporating a wireless node that is not operating normally as a relay terminal.

[5] In the wireless node device according to any one of [1], [2], and [4],
The communication control means includes
When an abnormality occurs in any of the plurality of wireless nodes, the adjacent wireless node adjacent to the downstream side of any of the wireless nodes is excluded from the relay terminal and the communication path is reconfigured. A wireless node device.
In the wireless node device configured as described above, the communication control unit is configured to be adjacent to the downstream side of any one of the plurality of wireless nodes when an abnormality occurs in any one of the wireless nodes. The wireless node is excluded from the relay terminal and the communication path is reconfigured.
That is, the adjacent wireless node that may be a secondary cause of the abnormality is not incorporated in the communication path reconfigured by the communication control unit.
Therefore, it is possible to avoid the occurrence of a failure and the spread due to the fact that an adjacent wireless node that has a secondary cause that any wireless node does not operate normally is incorporated into the communication path.

[6] In the wireless node device according to [5] above,
The communication control means includes
When reconfiguring the communication path, a section of a communication path in which a radio node located downstream of the adjacent radio node is maintained is maintained.
In the wireless node device having such a configuration, the communication control means maintains a section of a communication path in which a wireless node located on the downstream side of the adjacent wireless node is interposed when the communication path is reconfigured.
That is, of the existing communication path sections, the node where the abnormality has occurred and the section downstream of the adjacent node of the node are included in the communication path reconfigured by the communication control means.
Therefore, communication in such a section on the downstream side is performed without being changed after the communication path is reconfigured.

[7] Communication means arranged under a specific wireless node forming an ad hoc multi-hop communication network and operating as a relay terminal or a terminal of a communication path constituted by the specific wireless node;
A path storage unit configured to store the specific communication path that is configured by the specific wireless node and that the communication unit intervenes as the relay terminal or the terminal;
The communication means includes
The wireless node device using the specific communication path for communication with a wireless node on the specific communication path.
In the wireless node device having such a configuration, the communication means is arranged under a specific wireless node forming an ad hoc multi-hop communication network, and operates as a relay terminal or a terminal of a communication path formed by the specific wireless node. To do. The path storage means stores a specific communication path that is configured by the specific wireless node and that the communication means intervenes as the relay terminal or the terminal. The communication means uses the specific communication path for communication with a wireless node on the specific communication path.
That is, the specific communication path is used for communication with other wireless nodes (including a specific wireless node) on the specific communication path.
Therefore, in the wireless node device according to the present invention, a communication path that can be used for communication by the wireless node device is secured.

[8] In the wireless node device according to [7] above,
The route storage means
A wireless node device that identifies and stores the specific communication path based on both or either of the configuration of the ad hoc multi-hop communication network and the operation status of the ad hoc multi-hop communication network .
In the wireless node device having such a configuration, the path storage unit is configured to execute the specific identification based on the configuration of the ad hoc multihop communication network and / or the operating status of the ad hoc multihop communication network. Identify and store the communication path.
That is, the communication path that can be used for communication by the wireless node device according to the present invention is determined in consideration of the configuration of the ad hoc and multi-hop communication network formed by a specific wireless node and the operation status.
Therefore, a stable communication path can be secured.

[9] In the wireless node device according to [7] above,
The route storage means
A wireless node device characterized by preferentially storing a communication path with a small number of hops as the specific communication path.
In the wireless node device having such a configuration, the route storage unit preferentially stores a communication route with a small number of hops as the specific communication route.
That is, the number of hops of the communication path that can be used for communication by the wireless node device according to the present invention is suppressed to a small value.
Therefore, the communication speed is increased on average and the communication path is secured stably.

[10] In the wireless node device according to [7] above,
The route storage means
A wireless node device characterized by preferentially storing a communication path with high transmission quality as the specific communication path.
In the wireless node device having such a configuration, the path storage unit preferentially stores a communication path with high transmission quality as the specific communication path.
That is, the transmission quality of the communication path that can be used for communication by the wireless node device according to the present invention is maintained at a high value.
Therefore, a communication path with high transmission quality can be secured stably.

[11] In the wireless node device according to any one of [7] to [10],
A remaining amount monitoring means for monitoring a remaining amount of a battery that drives the communication means;
The communication means includes
The wireless node device, wherein the remaining amount of the battery is notified to the specific wireless node via the specific communication path.
In the wireless node device having such a configuration, the remaining amount monitoring unit monitors the remaining amount of the battery that drives the communication unit. The communication means notifies the remaining amount of the battery to the specific radio node via the specific communication path. That is, the specific radio node does not make an inquiry to the subordinate radio node device according to the present invention. However, it is possible to grasp the remaining battery level of the subordinate wireless node device.
Therefore, in the ad hoc multi-hop communication network to which the present invention is applied, the load of each wireless node increases or the overall communication speed does not decrease, and a better communication path can be obtained over a longer period than the conventional example. Maintains stability.
[12] Communication means that is arranged under a specific wireless node forming an ad hoc multi-hop communication network and operates as a relay terminal or a terminal of a specific communication path configured by the specific wireless node;
A notification means for notifying the specific wireless node of the failure when a failure occurs in the communication performed via the specific communication route with the wireless node on the downstream side of the specific communication route; A wireless node device.
In the wireless node device having such a configuration, the communication means is arranged under a specific wireless node forming an ad hoc multi-hop communication network, and is a relay terminal or terminal of a specific communication path formed by the specific wireless node Operates as The notifying means notifies the specific radio node of the failure when a failure occurs in communication performed via the specific communication path with a wireless node on the downstream side of the specific communication path.
When a failure occurs in communication with a wireless node on the downstream side on a specific communication path, the wireless node device according to the present invention passes through a section on the upstream side of the specific communication path. The failure can be notified to.
Therefore, even if the specific communication path is not reconfigured, the specific wireless node can identify a failure that occurred in a specific section of the specific communication route and take measures against the failure. Become.
[13] In the wireless node device according to [12] above,
Processing means for processing information delivered from the specific wireless node via the specific communication path;
The notification means includes
If there is a result of the processing, the wireless node device notifies the specific wireless node of the result of the processing together with the failure.
In the wireless node device configured as described above, in the wireless node device described in [12] above, the processing unit processes information delivered from the specific wireless node via the specific communication path. When there is a result of the processing, the notification means notifies the specific wireless node of the result of the processing together with the failure.
That is, the failure is included in a transmission unit common to the result of the processing described above, and is notified to a specific wireless node.
Therefore, such notification of a failure is achieved without unnecessarily increasing the transmission capacity of a specific communication path.
[14] In the wireless node device according to [12] or [13] above,
The notification means includes
The wireless node device, wherein the information necessary for specifying the section on the specific communication path where the failure has occurred is notified to the specific wireless node together with the failure.
In the wireless node device configured as described above, in the wireless node device described in [12] or [13], the notification unit is directed to the specific wireless node on the specific communication path where the failure has occurred. Information necessary for specifying the section is notified together with the failure.
That is, the failure is included in a common transmission unit with “information necessary for specifying the section on the specific communication path in which the failure has occurred”, and is notified to a specific wireless node.
Therefore, notification of such a failure is achieved in a form in which a specific node can cope with the failure without unnecessarily increasing the transmission capacity of the specific communication path.
[15] Communication means arranged under a specific wireless node forming an ad hoc multi-hop communication network and operating as a relay terminal or a terminal of a specific communication path formed by the specific wireless node;
When a failure occurring in an upstream section on the specific communication path is detected or identified, the adjacent wireless node that can be adjacent to the own station on the ad hoc multi-hop communication network is reconfirmed, and A wireless node device comprising: notification means for notifying a result of confirmation to the specific wireless node.
In the wireless node device having such a configuration, the communication means is arranged under a specific wireless node forming an ad hoc multi-hop communication network, and is a relay terminal or terminal of a specific communication path formed by the specific wireless node Operates as The notification means reconfirms an adjacent wireless node that can be adjacent to the own station on the ad hoc multi-hop communication network when a failure occurring in an upstream section on the specific communication path is detected or identified. Then, the result of the reconfirmation is notified to the specific wireless node.
In other words, the reconfirmation of the adjacent radio node that should be performed because a failure has occurred in the upstream section on the specific communication path is achieved without the intervention of a specific radio node above the radio node device according to the present invention. The result of such reconfirmation is reflected in the configuration of the ad hoc multi-hop communication network formed by the specific wireless node.
Therefore, the amount of processing to be ensured in the specific radio node in order to cope with a failure occurring in a section on the specific communication path is determined by a plurality of radio node devices arranged under the specific radio node. Mitigated under load balancing.
[16] Communication means that is arranged under a specific wireless node forming an ad hoc multi-hop communication network and operates as a relay terminal or a terminal of a specific communication path configured by the specific wireless node;
When a fault occurring in an upstream section on the specific communication path is detected or identified, an upstream wireless node located on the upstream side of the upstream section on the specific communication path and the ad hoc multi A notification means for notifying the specific wireless node of information necessary for reconfirmation of an adjacent wireless node that can be adjacent on the hop communication network and reconfiguration of a communication path based on the result of the reconfirmation. A wireless node device.
In the wireless node device having such a configuration, the communication means is arranged under a specific wireless node forming an ad hoc multi-hop communication network, and is a relay terminal or terminal of a specific communication path formed by the specific wireless node Operates as The notification means includes an upstream wireless node located on the upstream side of the upstream section on the specific communication path when a failure occurring in the upstream section on the specific communication path is detected or identified. Information necessary for reconfirmation of adjacent wireless nodes that can be adjacent on the ad hoc multi-hop communication network and reconfiguration of a communication path based on the result of the reconfirmation is notified to the specific wireless node.
That is, a failure that occurs in an upstream section on a specific communication path is dealt with under the initiative of the specific radio node under the control of the specific radio node (related to the present invention). Including wireless node devices).
Therefore, the amount of processing to be ensured in the specific radio node in order to cope with a failure occurring in a section on the specific communication path is determined by the plurality of radio node devices arranged under the specific radio node. Mitigated under functional distribution.
[17] Communication means arranged under a specific wireless node forming an ad hoc multi-hop communication network and operating as a relay terminal or a terminal of a specific communication path constituted by the specific wireless node;
When a failure occurring in an upstream section on the specific communication path is detected or identified, the upstream radio node located on the upstream side of the upstream section on the specific communication path Requests reconfirmation of an adjacent wireless node that can be adjacent to the node on the ad hoc multi-hop communication network, and notifies the specific wireless node of information necessary for reconfiguration of a communication path based on the reconfirmation result A wireless node device comprising: notification means for performing
In the wireless node device having such a configuration, the communication means is arranged under a specific wireless node forming an ad hoc multi-hop communication network, and is a relay terminal or terminal of a specific communication path formed by the specific wireless node Operates as The notification means is configured to notify an upstream wireless node located upstream of the upstream section on the specific communication path when a failure occurring in the upstream section on the specific communication path is detected or identified. Necessary to reconfirm neighboring wireless nodes that can be adjacent to the upstream wireless node on the ad hoc multi-hop communication network, and to reconfigure the communication path based on the result of the reconfirmation to the specific wireless node Notify information.
That is, the reconfirmation of the adjacent radio node that should be performed because a failure has occurred in the upstream section on the specific communication path is performed by linking the upstream radio node and the specific radio node that are above the radio node device according to the present invention. In addition, the result of such reconfirmation can be reflected on the configuration of the ad hoc multihop communication network formed by the specific wireless node.
Therefore, the amount of processing to be ensured in the specific radio node in order to cope with a failure occurring in a section on the specific communication path is determined by a plurality of radio node devices arranged under the specific radio node. Mitigated under load balancing.
[18] In the wireless node device according to any one of [15] to [17],
The ad hoc multi-hop communication network is
Formed by the specific wireless node without incorporating an abnormal wireless node;
The obstacle is
A wireless node device, wherein the wireless node device is detected or identified when the number of wireless nodes adjacent to the own station falls below a predetermined threshold on the ad hoc multi-hop communication network.
In the wireless node device configured as described above, in the wireless node device according to any one of [15] to [17], the ad hoc multi-hop communication network may be an abnormal wireless network depending on the specific wireless node. Nodes are formed without being incorporated. The failure is detected or identified when the number of wireless nodes adjacent to the own station falls below a predetermined threshold on the ad hoc multi-hop communication network.
That is, in any section on a specific communication path, in a wireless node in which a wireless node excluded as a cause of a failure that occurred corresponds to an adjacent node, the number of adjacent nodes of the wireless node becomes excessively small. It is avoided.
Therefore, the wireless node device according to the present invention can continue to operate stably and efficiently as a terminal node or a relay node on an ad hoc multi-hop communication network formed under a specific wireless node.
[19] Communication that forms an ad hoc multi-hop communication network by reconfiguring a communication path using the plurality of wireless nodes as relay terminals or terminals when any of a plurality of subordinate wireless nodes performs communication. Control means;
Communication means for communicating with the plurality of wireless nodes via the communication path,
The communication control means includes
When a failure occurring in any section of the communication path is notified from an upstream wireless node arranged upstream of the section among the plurality of wireless nodes, the downstream side of the section on the communication path Requesting a downstream wireless node arranged in the wireless node to reconfirm an adjacent wireless node of the downstream wireless node, and reconfiguring the communication path by reflecting the result of the reconfirmation.
In the wireless node device having such a configuration, the communication control unit reconfigures a communication path using the plurality of wireless nodes as relay terminals or terminals when any of the subordinate wireless nodes performs communication. Thus, an ad hoc multi-hop communication network is formed. The communication unit communicates with the plurality of wireless nodes via the communication path. When the communication control means is notified of an error occurring in any section of the communication path from an upstream wireless node arranged upstream of the section among the plurality of wireless nodes, the communication control means Then, the downstream wireless node arranged on the downstream side of the section is requested to reconfirm the adjacent wireless node of the downstream wireless node, and the communication path is reconfigured by reflecting the result of the reconfirmation.
In the wireless node device to which the present invention is applied, when a failure occurs in any section on the communication path, the failure is notified by an upstream wireless node arranged on the upstream side of the section.
Therefore, the wireless node according to the present invention can identify a failure that occurred in a specific section of the communication path and take measures for the failure without reconfiguring the communication path.
[20] When any one of a plurality of subordinate radio nodes performs communication, by reconfiguring a communication path using a normal radio node among the plurality of radio nodes as a relay terminal or a terminal, Communication control means for forming a multi-hop communication network;
Communication means for communicating with the plurality of wireless nodes via the communication path,
The communication control means includes
A failure occurring in any section of the communication path is notified from an upstream wireless node arranged upstream of the section among the plurality of wireless nodes, and the upstream wireless communication is performed on the ad hoc multi-hop communication network. When the number of wireless nodes adjacent to the node falls below a predetermined threshold, the downstream wireless node arranged on the downstream side of the section on the communication path is requested to reconfirm the adjacent wireless node of the downstream wireless node. Then, the communication path is reconfigured by reflecting the result of the reconfirmation.
In the wireless node device having such a configuration, the communication control means, when any of a plurality of wireless nodes under control, performs communication, selects a normal wireless node from the plurality of wireless nodes as a relay terminal or a terminal. An ad hoc multi-hop communication network is formed by reconfiguring the communication path to be performed. The communication unit communicates with the plurality of wireless nodes via the communication path. The communication control means is notified of a failure occurring in any section of the communication path from an upstream wireless node arranged upstream of the section among the plurality of wireless nodes, and the ad hoc multi-hop communication. When the number of wireless nodes adjacent to the upstream wireless node on the network falls below a predetermined threshold, the adjacent wireless of the downstream wireless node is connected to the downstream wireless node arranged on the downstream side of the section on the communication path. Requesting node reconfirmation and reconfiguring the communication path reflecting the result of the reconfirmation.
That is, in any section on the communication path, in the wireless node in which the wireless node excluded as the cause of the failure that occurred corresponds to the adjacent node, the number of adjacent nodes of the wireless node may be excessively reduced. Avoided.
Therefore, the radio node device according to the present invention can maintain high flexibility and transmission efficiency of an ad hoc multi-hop communication network while stably operating a plurality of subordinate radio nodes as terminal nodes or relay nodes.

10 Link 11 Access point (AP)
12 Host system 13 Gateway 13M Node management table 13GW, 14N Adjacent node list 14 Node 20 Path connection list 21 Measurement order list

Claims (5)

A communication means arranged under a specific wireless node forming an ad hoc multi-hop communication network and operating as a relay terminal or a terminal of a specific communication path configured by the specific wireless node;
When a failure occurring in an upstream section on the specific communication path is detected or identified, the adjacent wireless node that can be adjacent to the own station on the ad hoc multi-hop communication network is reconfirmed, and Notification means for notifying the specific wireless node of the result of confirmation;
A wireless node device comprising: A communication means arranged under a specific wireless node forming an ad hoc multi-hop communication network and operating as a relay terminal or a terminal of a specific communication path configured by the specific wireless node;
When a fault occurring in an upstream section on the specific communication path is detected or identified, an upstream wireless node located on the upstream side of the upstream section on the specific communication path and the ad hoc multi Notification means for notifying the specific wireless node of information necessary for reconfirmation of adjacent wireless nodes that can be adjacent on the hop communication network and reconfiguration of a communication path based on the result of the reconfirmation;
A wireless node device comprising: A communication means arranged under a specific wireless node forming an ad hoc multi-hop communication network and operating as a relay terminal or a terminal of a specific communication path configured by the specific wireless node;
When a failure occurring in an upstream section on the specific communication path is detected or identified, the upstream radio node located on the upstream side of the upstream section on the specific communication path Requests reconfirmation of an adjacent wireless node that can be adjacent to the node on the ad hoc multi-hop communication network, and notifies the specific wireless node of information necessary for reconfiguration of a communication path based on the reconfirmation result Notification means to
A wireless node device comprising: Communication control means for forming an ad hoc multi-hop communication network by reconfiguring a communication path having the plurality of wireless nodes as relay terminals or terminals when any of a plurality of subordinate radio nodes performs communication; ,
Communication means for communicating with the plurality of wireless nodes via the communication path,
The communication control means includes
When a failure occurring in any section of the communication path is notified from an upstream wireless node arranged upstream of the section among the plurality of wireless nodes, the downstream side of the section on the communication path Requesting the downstream wireless node arranged in the network to reconfirm the wireless node adjacent to the downstream wireless node, and reconfigure the communication path by reflecting the result of the reconfirmation.
A wireless node device. Ad hoc multi-hop communication by reconfiguring a communication path using a normal wireless node as a relay terminal or a terminal among the plurality of wireless nodes when any of the subordinate wireless nodes performs communication Communication control means for forming a network;
Communication means for communicating with the plurality of wireless nodes via the communication path,
The communication control means includes
A failure occurring in any section of the communication path is notified from an upstream wireless node arranged upstream of the section among the plurality of wireless nodes, and the upstream wireless communication is performed on the ad hoc multi-hop communication network. When the number of wireless nodes adjacent to the node falls below a predetermined threshold, the downstream wireless node arranged on the downstream side of the section on the communication path is requested to reconfirm the adjacent wireless node of the downstream wireless node. And reconfigure the communication path to reflect the result of the reconfirmation.
A wireless node device.