JP5945822B2 - Data collection system - Google Patents

Description

  The present invention relates to a data collection system in which a plurality of data collection nodes are connected in multiple stages to constitute a multi-hop network having a tree structure.

  In recent years, a system has been proposed in which data such as power consumption is collected by a data collection node from a meter installed in each home. In such a system, a plurality of data collection nodes are connected in multiple stages to form a tree-structured multi-hop network.

  In such a data collection system, the connection between the data collection nodes may be disconnected due to, for example, fluctuations in the radio wave environment around the data collection node. Conventionally, in such a case, there has been proposed a method of determining a connectable data collection node (alternative node) instead of the data collection node and performing data transmission (see, for example, Patent Document 1).

Japanese Patent No. 4517885

  However, in the conventional method, when the number of disconnected data collection nodes (child nodes) is large, connection request data (when all these data collection nodes try to connect to an alternative node (temporary parent node) ( There is a problem that it takes time until data transmission occurs.

  The present invention has been made to solve the above-described conventional problems, and provides a data collection system capable of suppressing occurrence of collision of connection request data to a temporary parent node and shortening time until data transmission. With the goal.

  The data collection node of the present invention is a data collection node constituting a data collection system. In the data collection system, a plurality of data collection nodes are connected in multiple stages to form a tree-structured multi-hop network, The data collection node includes a data collection unit that collects data from the data collection target, a process that functions as a lower data collection node and transmits data to a data collection node that is one level higher than the own node, and a higher data collection node And a function of receiving data from a data collection node one level lower than its own node, and a time-division processing unit that alternately performs time division, and when functioning as a higher-level data collection node, The data collected by the data collection node that is one level lower has been transmitted to the own node from the data collection node at the lower level. Disconnection determination that determines whether or not the connection between the flag receiving unit that receives the transmitted flag information indicating the above and the data collection node that is one level higher than the own node is disconnected when functioning as a lower data collection node When it is determined that the connection between the processing unit and the data collection node that is one level higher is disconnected, a connectable data collection node is selected as an alternative data collection node instead of the data collection node that is one level higher An alternative node selection unit, and a connection request unit that transmits connection request data to the alternative data collection node when functioning as a lower level data collection node. When all transmitted flag information has not been received from the collection node, connection request data is transmitted to the alternative data collection node, and If you have received all of the transmitted flag information from data collection node, and has a structure to suspend the sending of connection request data to the alternate data collection node.

  With this configuration, in the data collection node, processing as a lower data collection node (processing for transmitting collected data) and processing as a higher data collection node (processing for receiving transmitted data) It is done in divisions. When the data collection node functions as a lower data collection node (child node), if it is determined that the connection with the data collection node (parent node) one level higher is disconnected, an alternative that can replace the parent node A data collection node (temporary parent node) is selected, and connection request data is transmitted to the temporary parent node. When this data collection node functions as an upper data collection node (parent node), a transmitted flag indicating that the data collected by the child node has been transmitted from the data collection node (child node) one level lower Receive information. If all transmitted flag information has not been received, connection request data is transmitted to the temporary parent node. If all transmitted flag information has been received, connection request data is transmitted to the temporary parent node. Hold off to do. According to the present invention, when the connection with the parent node is disconnected, the connection request data having a high need for data collection is preferentially transmitted, thereby suppressing the occurrence of the collision of the connection request data with the temporary parent node. be able to.

  In the data collection node of the present invention, the connection request unit sends priority to sending connection request data to the alternative data collection node as the amount of transmitted flag information that has not been received from the data collection node one level lower is higher. It has a configuration in which the degree is set high.

  With this configuration, the higher the transmitted flag information that has not been received, the higher the priority for transmitting the connection request data to the temporary parent node. For example, the frequency and the number of times of transmitting connection request data to the temporary parent node are set large. Thereby, priority is given to connection request data with a higher necessity of data collection, and it can suppress the collision of the connection request data to a temporary parent node.

  In addition, the data collection node of the present invention selects the alternative data collection node, or if it fails to connect to the alternative data collection node, the data collection node that is not receiving the transmitted flag to the one-stage lower data collection node On the other hand, it has the structure provided with the search request | requirement part which transmits the search request | requirement for searching the data collection node which can be connected instead of a self-node.

  With this configuration, if the selection of the temporary parent node or connection with the temporary parent node fails, a search is made for a data collection node that can be connected to the child node that has not received the transmitted flag instead of its own node. A search request is sent to As a result, the child node can transmit data to the upper data collection node via the connectable data collection node instead of the self node.

  The data collection method of the present invention is a data collection method executed at a data collection node that constitutes a data collection system. The data collection method includes a process of collecting data from a data collection target, and functions as a lower-level data collection node. The process of transmitting data to the data collection node that is one level higher than the above and the process of receiving data from the data collection node that is one level lower than the own node functioning as the higher level data collection node are alternately performed in a time division manner. When processing and functioning as a higher-level data collection node, from the data collection node one level lower than its own node, the data collected by the data collection node one level lower has already been transmitted to the own node When processing to receive flag information and functioning as a lower data collection node, connection with the data collection node one level higher than the own node is established. A data collection node that can be connected instead of the data collection node that is one level higher when it is determined that the connection with the data collection node that is one level higher is disconnected. A process of selecting as an alternative data collection node and a process of transmitting connection request data to the alternative data collection node when functioning as a lower data collection node, and in the process of transmitting the connection request data, If all transmitted flag information has not been received from the one-stage lower data collection node, connection request data is transmitted to the alternative data collection node, and all transmitted flags are transmitted from the first-stage lower data collection node. When the information is received, transmission of connection request data to the alternative data collection node is suspended.

  Also in this method, as described above, when the connection with the parent node is disconnected, the connection request data with a high necessity for data collection is preferentially transmitted so that the connection request data collides with the temporary parent node. Can be suppressed.

  The data collection system of the present invention is a data collection system in which a plurality of data collection nodes are connected in multiple stages to constitute a multi-hop network having a tree structure, and the data collection node collects data from a data collection target. A data collection node that functions as a lower-level data collection node and transmits data to a data collection node that is one level higher than its own node, and a data collection node that functions as a higher-level data collection node and that is one level lower than its own node The time-division processing unit that alternately performs the process of receiving data from the time-division and the data collection node that is one level lower than its own node when functioning as a higher-level data collection node. A flag receiving unit that receives transmitted flag information indicating that data collected by the collecting node has been transmitted to the own node, and a lower level When functioning as a data collection node, the disconnection determination processing unit that determines whether or not the connection with the data collection node that is one level higher than its own node is disconnected, and the connection between the data collection node that is one level higher is disconnected When it is determined that a data collection node that can be connected instead of the one-stage higher data collection node is selected as an alternative data collection node, and when it functions as a lower data collection node A connection request unit that transmits connection request data to the alternative data collection node, and when the connection request unit has not received all transmitted flag information from the data collection node that is one stage lower, Connection request data is transmitted to the alternative data collection node, and all transmitted flag information is received from the data collection node one level lower The case has a configuration to withhold from transmitting connection request data to the alternate data collection node.

  In this system as well, when the connection with the parent node is disconnected, the connection request data that has a high need for data collection is preferentially transmitted so that the connection request data collides with the temporary parent node. Can be suppressed.

  The present invention can provide a data collection system that can suppress the occurrence of collision of connection request data to a temporary parent node and can shorten the time until data transmission. .

Explanatory drawing which shows the structure of the data collection system in embodiment of this invention The block diagram which shows the structure of the data collection node in embodiment of this invention Explanatory drawing of the data transmission / reception by the time division in embodiment of this invention Flow chart for explaining the operation of the data collection node (parent node) in the embodiment of the present invention Flow chart for explaining the operation of the data collection node (child node) in the embodiment of the present invention

  Hereinafter, a data collection system according to an embodiment of the present invention will be described with reference to the drawings. In the present embodiment, a case of a data collection system used for a system or the like that collects meter values (electric power consumption, etc.) from meters installed in each home will be exemplified.

  A configuration of a data collection system according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram showing the configuration of the data collection system of the present embodiment. As shown in FIG. 1, in the data collection system 1 of this embodiment, a plurality of data collection nodes 2 (also simply referred to as “nodes”) are connected in multiple stages to form a tree-structured multi-hop network. In FIG. 1, for convenience of explanation, only 12 data collection nodes 2 (nodes A to L) are shown, but it goes without saying that the number of data collection nodes 2 is not limited to this. In the example of FIG. 1, the state in which the nodes F and G (child nodes) communicate with the node B (temporary parent node) when the communication with the node C (parent node) is disconnected is shown. .

  FIG. 2 is a block diagram illustrating a configuration of the data collection node 2 according to the present embodiment. As shown in FIG. 2, the data collection node 2 includes a data collection unit 3, a data transmission / reception unit 4, and a control unit 5. The data collection unit 3 collects data such as power consumption from a meter (data collection target, not shown) installed in each home. The data transmission / reception unit 4 has a function of transmitting data to the data collection node 2 (parent node) that is one level higher and a function that receives data from the data collection node 2 (child node) that is one level lower.

  The control unit 5 includes a time division processing unit 6, a disconnection determination processing unit 7, and an alternative node selection unit 8. The time division processing unit 6 transmits data to the data collection node 2 that is one level higher (processing as a lower node), and receives data from the data collection node 2 that is one level lower (processing as an upper node) ) And control for alternately performing in a time-sharing manner.

  Here, transmission and reception of data in time division will be described with reference to FIG. As shown in FIG. 3, for example, a certain data collection node 2 (node C) functions as a lower node at a certain time T1 to T2, and transmits data to the upper data collection node 2 (node A). . The data collection node 2 (node C) functions as an upper node at the next time T2 to T3, and receives data from the data collection node 2 (node G), which is one stage lower. This is repeated thereafter. In this way, data is transmitted and received in parallel throughout the system.

  When the data collection node 2 functions as a lower data collection node (child node), the disconnection determination processing unit 7 is based on the number of failed data transmission / receptions with the data collection node (parent node) one level higher than its own node. Then, it is determined whether or not the connection with the parent node is disconnected. For example, the nodes F and G determine that the connection with the node C is disconnected when the beacons transmitted from the node C cannot be received three times in succession (see FIG. 1).

  When it is determined that the connection with the parent node is disconnected, the alternative node selection unit 8 scans the connectable data collection node 2 instead of the parent node and selects it as an alternative data collection node (temporary parent node) To do. For example, when it is determined that the connection with the node C is disconnected, the nodes F and G select the node B as a temporary parent node (see FIG. 1).

  The temporary parent node may be selected, for example, by preferentially selecting a node for which data collection has been completed among parent nodes in the same time phase. Alternatively, a node having the smallest number of hops among such parent nodes may be selected with priority.

  On the other hand, when the data collection node 2 functions as an upper data collection node (parent node), the data transmission / reception unit 4 collects data collected by the child node from the data collection node (child node) one level lower than the own node. Is transmitted to the own node to receive the transmitted flag information. For example, when the node H has completed transmission of data collected by the node H to the node F, the node F receives the transmitted flag information from the node H (see FIG. 1).

  The control unit 5 includes a connection request unit 9 and a search request unit 10. When the data collection node 2 functions as a lower data collection node (child node), the connection request unit 9 has a function of transmitting connection request data data to the alternative data collection node (temporary parent node). The connection request unit 9 transmits the connection request data to the alternative data collection node (temporary parent node) when not receiving all the transmitted flag information from the data collection node (child node) that is one step lower. For example, the node F transmits connection request data to the node B when not receiving all the transmitted flag information (transmitted flag information of the nodes H, J, and K) from the node H (see FIG. 1). .

  On the other hand, the connection request unit 9 transmits the connection request data to the alternative data collection node (temporary parent node) when all transmitted flag information is received from the data collection node (child node) one level lower. Hold on. For example, when all the transmitted flag information (transmitted flag information of the nodes I and L) is received from the node G, the node G suspends transmission of connection request data to the node B. The pending connection request data is controlled to be transmitted at the next transmission timing, for example (see FIG. 1).

  Further, the connection request unit 9 increases the priority of transmitting the connection request data to the alternative data collection node (temporary parent node) as the transmitted flag information that has not been received from the data collection node (child node) that is one step lower is larger. Set high. For example, the frequency (number of times) at which connection request data is transmitted is set higher when two pieces of transmitted flag information are not received than when one piece of transmitted flag information is not received.

  In addition, the search request unit 10 has been transmitted when the own node fails to select the alternative data collection node (temporary parent node) or when the own node fails to connect to the alternative data collection node (temporary parent node). A search request for searching for a connectable data collection node instead of the own node is transmitted to a data collection node (child node) one level lower than that which has not received the flag. For example, when the node F fails to select or connect to the temporary parent node, the node F can connect to the child node H that has not received the transmitted flag instead of the node F (for example, the node F). A search request for searching for E and the like is transmitted (see FIG. 1).

  The operation of the data collection system configured as described above will be described with reference to the drawings.

  First, the operation of the data collection node (in the case of a parent node) according to the present embodiment will be described with reference to the flowchart of FIG. As shown in FIG. 4, when the data collection node 2 functions as a parent node, the data collection node 2 collects data such as power consumption from a meter installed at home (S10), and the child node collects it. Data is received from the child node (S11). For example, the parent node F receives data collected by the child node H from the child node H (see FIG. 1).

  When data reception from the child node is completed (S12), the data collection node 2 turns on the transmitted flag of the child node (S13). For example, the child node H transmits the transmitted flag information to the parent node F when the data transmission is completed. When the parent node F receives the transmitted flag information from the child node H, the parent node F turns on the transmitted flag of the child node H (see FIG. 1).

  Next, the operation of the data collection node (in the case of a child node) according to the present embodiment will be described with reference to FIG. As shown in FIG. 5, when the data collection node 2 functions as a child node, when the connection with the parent node is disconnected (S20), a temporary parent node that can substitute for the parent node is selected (S21). If the connection with the parent node is not disconnected (S20), data transmission is performed to the parent node (S22).

  When the temporary parent node is selected (S21), if all the transmitted flags of the child nodes are ON (S23), transmission of connection request data to the temporary parent node is suspended (S24). On the other hand, if all the transmitted flags of the child nodes are not ON, connection request data to the temporary parent node is transmitted (S25).

  If the connection with the temporary parent node is successful (S26), data transmission to the temporary parent node is performed (S27). On the other hand, when the connection with the temporary parent node fails (S27), a search request is transmitted to the child node (S28). Note that the transmission of the search request to the child node (S28) may be performed when the temporary parent node selection (S21) fails.

  According to the data collection system 1 of this embodiment as described above, it is possible to suppress the occurrence of collision of connection request data to the temporary parent node, and it is possible to shorten the time until data transmission.

  That is, in the data collection node 2 of the present embodiment, processing as a lower data collection node (child node) (processing for transmitting collected data) and processing as a higher data collection node (parent node) (transmission) The process of receiving the received data) is performed in a time-sharing manner. When the data collection node 2 functions as a lower data collection node (child node), if it is determined that the connection with the data collection node (parent node) one level higher is disconnected, it can be used instead of the parent node An alternative data collection node (temporary parent node) is selected, and connection request data is transmitted to the temporary parent node. When this data collection node 2 functions as a higher-level data collection node (parent node), it has been transmitted indicating that data collected by the child node has been transmitted from the data collection node (child node) one level lower Receive flag information. If all transmitted flag information has not been received, connection request data is transmitted to the temporary parent node. If all transmitted flag information has been received, connection request data is transmitted to the temporary parent node. Hold off to do. According to such a data collection system 1, when the connection with the parent node is disconnected, the connection request data having a high necessity for data collection is preferentially transmitted, so that the connection request data to the temporary parent node is transmitted. The occurrence of collision can be suppressed.

  In this embodiment, the higher the transmission flag information that has not been received, the higher the priority for transmitting connection request data to the temporary parent node. For example, the frequency and the number of times of transmitting connection request data to the temporary parent node are set large. Thereby, priority is given to connection request data with a higher necessity of data collection, and it can suppress the collision of the connection request data to a temporary parent node.

  In this embodiment, when the selection of the temporary parent node or the connection with the temporary parent node fails, data that can be connected to the child node that has not received the transmitted flag instead of the own node A search request for searching for a collection node is transmitted. As a result, the child node can transmit data to the upper data collection node via the connectable data collection node instead of the self node.

  The embodiments of the present invention have been described above by way of example, but the scope of the present invention is not limited to these embodiments, and can be changed or modified according to the purpose within the scope of the claims. is there.

  As described above, the data collection system according to the present invention is capable of suppressing the occurrence of collision of connection request data to the temporary parent node, and has the effect of reducing the time until data transmission, It is useful as a system for collecting meter values (electric power consumption, etc.) from meters installed in each household.

DESCRIPTION OF SYMBOLS 1 Data collection system 2 Data collection node 3 Data collection part 4 Data transmission / reception part 5 Control part 6 Time division process part 7 Disconnection determination process part 8 Alternative node selection part 9 Connection request part 10 Search request part

Claims (5)

A data collection node constituting a data collection system,
In the data collection system, a plurality of data collection nodes are connected in multiple stages to form a multi-hop network having a tree structure,
The data collection node is:
A data collection unit that collects data from the data collection target;
A function that functions as a lower data collection node to transmit data to a data collection node that is one level higher than its own node and a function that functions as a higher level data collection node and receives data from a data collection node that is one level lower than its own node A time-division processing unit that alternately performs time-division processing, and
When functioning as an upper data collection node, transmitted flag information indicating that data collected by the data collection node one level lower than the own node has been transmitted to the own node from the data collection node one level lower than the own node. A flag receiver to receive;
A disconnection determination processing unit that determines whether or not the connection with the data collection node one level higher than the own node is disconnected when functioning as a lower data collection node;
Alternative node selection that selects a connectable data collection node as an alternative data collection node instead of the one-stage higher data collection node when it is determined that the connection with the upper data collection node is disconnected And
A connection request unit for transmitting connection request data to the alternative data collection node when functioning as a lower data collection node;
With
The connection request unit
If all transmitted flag information has not been received from the data collection node that is one level lower, send connection request data to the alternative data collection node;
A data collection node characterized in that, when all transmitted flag information has been received from the data collection node that is one level lower, transmission of connection request data to the alternative data collection node is suspended.   The connection request unit sets a higher priority for transmitting connection request data to the alternative data collection node as the amount of transmitted flag information that has not been received from the data collection node one level lower is higher. The data collection node according to claim 1.   When selection of the alternative data collection node or connection with the alternative data collection node fails, connection can be made instead of the own node to the data collection node one level lower that has not received the transmitted flag The data collection node according to claim 1, further comprising a search request unit that transmits a search request for searching for a new data collection node. A data collection method executed at a data collection node constituting a data collection system,
A process of collecting data from the data collection target;
A function that functions as a lower data collection node to transmit data to a data collection node that is one level higher than its own node and a function that functions as a higher level data collection node and receives data from a data collection node that is one level lower than its own node Processing to alternately perform in a time-sharing manner,
When functioning as an upper data collection node, transmitted flag information indicating that data collected by the data collection node one level lower than the own node has been transmitted to the own node from the data collection node one level lower than the own node. Processing to receive,
When functioning as a lower data collection node, a process for determining whether or not the connection with the data collection node one level higher than the own node is disconnected;
A process of selecting a connectable data collection node as an alternative data collection node instead of the one-stage higher data collection node when it is determined that the connection with the one-stage higher data collection node is disconnected;
A process of transmitting connection request data to the alternative data collection node when functioning as a lower data collection node;
Including
In the process of transmitting the connection request data,
If all transmitted flag information has not been received from the data collection node that is one level lower, send connection request data to the alternative data collection node;
A data collection method characterized by suspending transmission of connection request data to the alternative data collection node when all transmitted flag information has been received from the data collection node that is one level lower. A data collection system in which a plurality of data collection nodes are connected in multiple stages to constitute a multi-hop network having a tree structure,
The data collection node is:
A data collection unit that collects data from the data collection target;
A function that functions as a lower data collection node to transmit data to a data collection node that is one level higher than its own node and a function that functions as a higher level data collection node and receives data from a data collection node that is one level lower than its own node A time-division processing unit that alternately performs time-division processing, and
When functioning as an upper data collection node, transmitted flag information indicating that data collected by the data collection node one level lower than the own node has been transmitted to the own node from the data collection node one level lower than the own node. A flag receiver to receive;
A disconnection determination processing unit that determines whether or not the connection with the data collection node one level higher than the own node is disconnected when functioning as a lower data collection node;
Alternative node selection that selects a connectable data collection node as an alternative data collection node instead of the one-stage higher data collection node when it is determined that the connection with the upper data collection node is disconnected And
A connection request unit for transmitting connection request data to the alternative data collection node when functioning as a lower data collection node;
With
The connection request unit
If all transmitted flag information has not been received from the data collection node that is one level lower, send connection request data to the alternative data collection node;
A data collection system that suspends transmission of connection request data to the alternative data collection node when all transmitted flag information is received from the data collection node that is one level lower.

Images