JP2015109596A - Design support device and design support method for sensor network system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To support design for a sensor network.SOLUTION: A design support device for a sensor network system comprises: a storage unit for storing first plan information including information on a communication terminal to be installed in a predetermined area until a first time point and second plan information including information on a communication terminal to be installed in the predetermined area until a second time point after the first time point; and a communication system selection unit for selecting a communication system for the communication terminal in the predetermined area transmitting data to a server from communication systems previously prepared, on the basis of the second plan information.

Description

  The present invention relates to a design support apparatus and a design support method for supporting the design of a sensor network.

  To realize a smart grid, a smart meter that transmits power consumption data and the like to the server and receives request data from the server is necessary. When planning the installation of smart meters, it is necessary to consider both communication quality and installation costs.

  In Patent Document 1, a plurality of different installation patterns of PHS base stations are prepared for a predetermined service plan area, and electric field intensity distribution is simulated for each installation pattern. Based on this, the ratio of the area of the callable area to the area of the service plan area is calculated as a quality evaluation value. Based on the quality evaluation value and the cost evaluation value for each installation pattern, the service plan is selected from all the installation patterns. A technique for determining an installation pattern for an area is disclosed.

JP-A-8-317458

  However, it is difficult to replace all existing watt-hour meters with smart meters in a short period of time, and it is thought that existing watt-hour meters will be gradually replaced with smart meters. In such a case, the communication means of the smart meter at a certain point in time is not always optimal from the viewpoint of long-term communication quality and cost. For example, as a communication means of a smart meter, if only a certain point in time is considered, even if 3G (3rd Generation) / LTE (Long Term Evolution) communication is optimal in terms of communication quality and cost, another communication will be required in the long term. There may be a case where the means is optimal in terms of communication quality and cost. This applies not only to the smart meter but also to a sensor network design plan using other communication terminals.

  An object of the present invention is to provide a design support apparatus and a design support method that support creation of a sensor network design plan in consideration of long-term communication quality and cost.

A network system design support apparatus according to an embodiment of the present invention includes:
First plan information including information on communication terminals scheduled to be installed in a predetermined area by the first time point, and information on communication terminals scheduled to be installed in the predetermined area by a second time point after the first time point Storage unit for storing second plan information including
A communication method selection unit that selects a communication method for a communication terminal in a predetermined area to transmit data to a server from communication methods prepared in advance based on the second plan information.

  ADVANTAGE OF THE INVENTION According to this invention, the plan of the suitable sensor network design which considered long-term communication quality and cost can be made.

It is a figure which shows the outline | summary of the function which the design support apparatus of a sensor network has. It is a figure which shows the structural example of a sensor network design system. It is a flowchart for demonstrating the outline | summary of the process in a design assistance apparatus. The structural example of a terminal information table is shown. The structural example of a communication expense information table is shown. The structural example of a calculation condition table is shown. The structural example of a communication characteristic table is shown. It is a flowchart which concerns on the process example which determines the communication classification of a terminal. It is a flowchart which concerns on the process example which produces | generates the installation plan which added the base station or the relay machine so that a connection rate may become more than a request | requirement connection rate. It is a table | surface which shows the communication classification applicable to a target area. It is a table | surface which shows the installation operation cost at the time of applying the communication classification to a target area. It is an example of the graph which displayed the cost per terminal for every communication classification in each area. It is an example of the graph which displayed the cost according to the year in each area. It is an example of a display of the installation plan of the initial stage of the terminal etc. in an area. It is an example of a display of the final stage installation plan, such as a terminal in an area. The process example in the case of installing a base station or a relay machine in a target area is shown.

  Embodiments relating to a design support apparatus for supporting sensor network design will be described below with reference to the drawings. In this embodiment, a network design using a smart meter as a terminal will be described as an example of a sensor network.

  FIG. 1 is a block diagram showing an outline of functions of a sensor network design support apparatus 10. The design support apparatus 10 includes a communication method selection unit 11, a connection rate calculation unit 12, a plan correction unit 13, a cost calculation unit 14, a display processing unit 15, and a storage unit 16 as functions. These functions 11 to 16 are realized by using resources such as a CPU (central processing unit), a memory, and a storage device included in the design support apparatus 10. For example, the design support apparatus 10 implements the functions 11 to 15 by executing a predetermined computer program stored in the storage unit 16 using a CPU and a memory.

  The storage unit 16 includes, in a predetermined area, first plan information 21 including information of communication terminals scheduled to be installed by the first time point (hereinafter referred to as “terminal”), and second plan information after the first time point. The second plan information 22 including the information of the terminal scheduled to be installed is stored. The first plan information 21 may include information such as a relay station and / or a base station scheduled to be installed by the first time point. The second plan information 22 may include information such as a relay station and / or a base station scheduled to be installed by the second time point. A repeater is a device for relaying data to other terminals, for example, in multi-hop wireless communication. The multi-hop wireless communication system is a kind of ad hoc wireless communication, in which terminals transmit and receive data to and from a base station by transferring data like so-called bucket relays. That is, in the case of multi-hop wireless communication, a terminal in the middle plays the role of a relay machine, but a relay machine is installed when the distance between the terminals is too long to transfer data between terminals. For example, the base station is a device for transmitting data transmitted from each terminal to a predetermined server. The terminal is, for example, a smart meter for measuring electric energy.

  Based on the second plan information 22, the communication method selection unit 11 selects a communication method for a terminal arranged in a predetermined area to transmit data to the server. For example, the communication method selection unit 11 selects an appropriate communication method in a predetermined area from multi-hop wireless communication, 3G / LTE communication, long-distance wireless communication, FTTH, and PLC that are prepared in advance. The server is, for example, a server that collects power consumption data from a smart meter. The communication method selection unit 11 may select an appropriate communication method in the predetermined area based on the installation density of the communication terminal in the predetermined area included in the second plan information 22. For example, when the installation density is equal to or higher than a predetermined threshold, a multi-hop wireless communication method may be selectable. The planned installation density is a value indicating the ratio of the planned number of communication terminals to the area of the area. For example, “scheduled installation density = number of installed communication terminals / area of area” may be used.

  The connection rate calculation unit 12 calculates a connection rate in a predetermined area when the communication method selected by the communication method selection unit 11 is applied to the first plan information 21. The connection rate is a value indicating a ratio of terminals that can transmit data to a server among all communication terminals existing in a predetermined area. For example, it may be calculated as “predetermined area connection rate = number of terminals communicable with server / number of all terminals”.

  Whether the plan modification unit 13 satisfies the first design condition for the first time point when the communication method selected based on the second plan information 22 for the predetermined area is applied to the first plan information 21 If the first design condition is not satisfied, the first plan information is corrected so as to satisfy the first design condition. The first design condition may include, for example, a condition that the connection rate calculated by the connection rate calculation unit 12 is equal to or higher than the required connection rate required at the first time point. The required connection rate may be higher every year. The plan correction unit 13 determines that the connection rate is equal to or higher than the required connection rate when the selected communication method is a multi-hop wireless communication method and the connection rate calculated based on the first plan information is less than the required connection rate. In this way, a modification may be made in which a necessary repeater is added to the first plan information.

  The cost calculation unit 14 is installed by the second time point in the predetermined area when the selected communication method is applied based on the first plan information and the second plan information corrected by the plan correction unit 13. Calculate costs for planned repeaters and communication terminals. The cost calculation unit 14 may calculate the cost when each communication method is selected when the communication method selection unit 11 can select two or more communication methods. Costs related to the relay device and the terminal may include costs required for installation of the relay device and the terminal and costs required for operation of the relay device and the terminal based on the selected communication method.

  When the cost calculation unit 14 calculates costs for two or more communication methods, the display processing unit 15 displays the costs in a manner that allows comparison. The display processing unit 15 may display the expenses for each year in a manner that can be compared (for example, a table, a bar graph, a line graph, etc.). The display processing unit 15 may display the planned installation positions of communication terminals, repeaters, and base stations for each year in a predetermined area together with a map.

Details of the present embodiment will be described below.
FIG. 2 shows a configuration example of a sensor network design support system (hereinafter referred to as “design support system”). The design support system 100 includes a design support device 101 and one or more input / output devices 121, and these devices 101 and 121 transmit and receive data via a communication network 140. The communication network 140 is, for example, the Internet network or a dedicated line network.

  The design support apparatus 101 executes processing related to sensor network design. The input / output device 121 receives input from the user, or displays a calculation result or the like related to the sensor network design generated by the design support device 101.

  The design support apparatus 101 includes a CPU 102, a memory 103, a storage device 105, and a communication I / F 124. The design support apparatus 101 implements various functions to be described later by reading a predetermined computer program stored in the storage device 105 to the memory 103 and executing it by the CPU 102 as necessary. The storage device 105 is, for example, an HDD (hard disk drive) or a flash memory.

  The communication I / F 104 of the design support apparatus 101 is an I / F for connecting the design support apparatus 101 to the communication network 141.

  The storage device 105 of the design support apparatus 101 stores a data confirmation unit 111, a data calculation unit 112, and a data input / output unit 113 as a kind of computer program. Further, the storage device 105 stores a terminal information table 106, a communication cost information table 107, a calculation condition table 108, a communication characteristic information table 114, a calculation result 109, and an annual calculation result 110 as data. Is done. Details of the terminal information table 106, the communication cost information table 107, and the calculation condition table 108 will be described later (see FIGS. 4, 5, and 6).

  The calculation result 109 stores, for each area, an appropriate communication type of the terminal, the planned installation number and installation position of the terminal, the planned installation number and installation position of the base station and the repeater, and the like. The annual calculation result 110 stores the connection rate, installation cost, operation cost, and the like for each area calculated for each area.

  The data confirmation unit 111 confirms the validity of the data stored in the table, confirms the data transmitted from the input / output device 120, and duplicates the data as necessary.

  The data calculation unit 112 performs various calculations related to sensor network design based on the data and conditions stored in the table.

  The data input / output unit 113 receives data directly input to the design support apparatus 101 through a keyboard or the like, or transmitted from the input / output apparatus 121, as necessary, a terminal information table 106, a communication cost information table 107, a calculation condition. Register in the table 108, the communication characteristic information table 114, the calculation result 109 and / or the annual calculation result 110;

  The data input / output unit 113 reads data from the terminal information table 106, the communication cost information table 107, the calculation condition table 108, the communication characteristic information table 114, the calculation result 109, and / or the annual calculation result 110 as necessary. The data is transmitted to the input / output device 120 or displayed on a predetermined display.

  The input / output device 121 includes a CPU 122, a memory 123, and a storage device 125. The input / output device 121 implements various functions to be described later by reading a predetermined computer program stored in the storage device 125 to the memory 123 and executing it by the CPU 122 as necessary. The communication I / F 124 of the input / output device 121 is an I / F for connecting the input / output device 121 to the communication network 141. The storage device 125 is, for example, an HDD (hard disk drive) or a flash memory.

  The storage device 125 of the input / output device 121 stores a data input unit 131 and a data display unit 132 as a kind of computer program. The storage device 125 also stores terminal information 126, communication cost information 127, calculation conditions 128, communication characteristic information 131, calculation results 129, and annual calculation results 130 as data.

  The input / output device 121 may acquire data stored in the calculation result 109 of the design support apparatus 101 and hold it in the calculation result 129. The input / output device 121 may acquire data stored in the annual calculation result 110 of the design support apparatus 101 and hold it in the annual calculation result 130.

  The data input unit 131 of the input / output device 121 accepts input of data such as terminal information 126, communication cost information 127, calculation conditions 128 and / or communication characteristic information 131.

  The data display unit 132 of the input / output device 121 displays information such as the calculation result 129 and the annual calculation result 110 calculated by the design support apparatus 101 on a predetermined display device or the like. Display examples of these pieces of information will be described later (see FIGS. 12, 13, 14, 15, and 16).

  Next, an overview of processing in the design support apparatus 101 will be described with reference to the flowchart shown in FIG.

  The user of the design support apparatus 101 inputs design conditions to the design support apparatus 101 (S201). Design conditions include, for example, the period of the target year of processing, the target area as “predetermined area”, the planned installation position of the smart meter as “communication terminal”, the required connection rate in the target area, and the installation and operation of the smart meter. The upper limit of the budget etc. is input. The connection rate is a ratio of smart meters that can transmit and receive data by wireless or wired communication to all smart meters in the target area. The required connection rate is the minimum connection rate required for the target area. Therefore, in the target area, a connection rate higher than the required connection rate is required. The user may be, for example, a power company, a gas company, a water company, a communication company, a local government, or a smart meter management company.

  The design support apparatus 101 selects an appropriate communication type based on the input design conditions (S202). The communication type is a type of communication method adopted by the smart meter. For example, the design support apparatus 101 includes 3G / LTE communication (3GPP), multi-hop wireless communication (IEEE 802.11, IEEE 802.15.4), long-distance wireless communication (IEEE 802.16), and FTTH (fiber to the home). An appropriate communication type is selected from communication types such as PLC (power line communication).

  The design support apparatus 101 calculates the installation operation cost of the smart meter or the like in the target area based on the input design condition and the selected communication type (S203). The installation operation cost may include a cost required for installing the smart meter and a cost required for operating the smart meter. Information that is the basis for calculating the installation and operation cost of the smart meter may be held in the design support apparatus 101 in advance, or may be input by the user through the input / output device 121.

The design support apparatus 101 calculates a connection rate in the target area based on the input design condition and the selected communication type (S204).
The design support apparatus 101 determines whether or not the calculated connection rate is equal to or higher than the requested connection rate input as the design condition (connection rate ≧ required connection rate) (S205).

  When the connection rate is equal to or higher than the required connection rate (S205: YES), the design support apparatus 101 outputs information about the calculation result (S209), and ends the processing (END).

  When the connection rate is less than the required connection rate (S205: NO), the design support apparatus 101 generates an installation plan in which base stations and / or relays are added so that the connection rate is equal to or higher than the required connection rate ( S206).

The design support apparatus 101 calculates the installation operation cost in the installation plan (S207).
When the year to be processed remains (S208: NO), the design support apparatus 101 executes S206 and S207 for an unprocessed year. If the design support apparatus 101 completes S206 and S207 for all the fiscal years to be processed (S208: YES), it outputs information about the calculation result (S209) and ends the process (END).

  Next, details of information serving as a basis for calculating the installation and operation cost of the terminal and details of design conditions will be described with reference to the drawings.

FIG. 4 shows a configuration example of the terminal information table 106.
The terminal information table 106 manages terminal information including information related to terminals. The terminal information includes, as items, a terminal ID 301, an access permission 302, a terminal position 303, an installation plan year 305, house information 306, and line information 307.

In the terminal ID 301, an ID for identifying the terminal is registered.
In the access permission 302, a user ID of a user who can access this terminal information is registered. Therefore, a user who is not registered in the access permission 302 cannot use this terminal information.
In the terminal position 303, the position where the terminal is to be installed is registered. The terminal position 303 may be, for example, longitude and latitude, or may be X and Y coordinates on the map.
In the planned installation year 305, the year in which the terminal is scheduled to be installed is registered.

  In the house information 306, information related to the house where the terminal is to be installed is registered. In the house information 306, for example, a house type such as a detached house, a small apartment, a medium-sized apartment, a high-rise apartment, or a district hall may be registered. This is because the housing information 306 may change an appropriate communication line or limit a usable communication line.

  In the line information 307, information indicating what kind of communication line can be used in the area where the terminal related to the terminal information is installed is registered. In the line information 307, for example, the radio wave status of 3G / LTE communication, the FTTH laying status, the status of undergrounding of the communication line, etc. at the place where the terminal is installed are registered. The line information 307 is used to determine an appropriate communication type at the place where the terminal is installed.

FIG. 5 shows a configuration example of the communication cost information table 107.
The communication cost information table 107 manages information related to communication costs for each communication type. The communication cost information includes, as items, a communication type 401, an access permission 402, a terminal installation cost 403, a terminal operation cost 404, a base station installation cost 405, and a base station operation cost 406.

  In the communication type 401, the type of communication is registered. In the communication type 401, for example, 3G / LTE communication, multi-hop wireless communication, long-distance wireless communication, or the like is registered.

The access permission 402 is as described above with reference to FIG.
In the terminal installation cost 403, the cost when one terminal corresponding to the communication type 401 is installed is registered.
Registered in the terminal operation cost 404 is a cost when one terminal corresponding to the communication type 401 is operated for one month.
The base station installation cost 405 stores the cost when one base station corresponding to the communication type 401 is installed.
Registered in the base station operation cost 406 is a cost when one base station corresponding to the communication type 401 is operated for one month.

FIG. 6 shows a configuration example of the calculation condition table 108.
The calculation condition table 108 manages calculation conditions for each user. The calculation conditions include a user ID 501, a year 502, a required connection rate 503, an installation cost upper limit 504, an operation cost upper limit 505, and a priority 506.

In the user ID 501, an ID for identifying the user is registered.
In the year 502, the year targeted by the calculation condition is registered. This is because the calculation conditions can vary from year to year.

  In the required connection rate 503, the lowest connection rate that should be satisfied in the year 502 is registered. As described above, the connection rate is a value indicating the ratio of terminals that can transmit / receive data to / from a predetermined server among all terminals installed in the area. For example, in a certain area, if 1000 terminals are installed by FY2014, and the required connection rate 503 in that area is “83% or more”, 830 or more terminals will be connected to the network by FY2014. It is required to design a sensor network so that it can be connected.

In the installation cost upper limit 504, the upper limit of the budget allocated to the installation of terminals and base stations in the year 502 is registered.
In the operation cost upper limit 505, the upper limit of the budget allocated to the operation of the terminal and the base station in the year 502 is registered.
In the priority ranking 506, a ranking indicating which condition of the connection rate, installation cost, and operation cost is to be prioritized is registered.

  For example, referring to the calculation condition table 108, the required connection rate in “2013” for the user ID “user A” is “80% or more”, the installation cost upper limit is “10 billion yen”, and the operation cost upper limit is “500 million It can be seen that “Yen” and “priority” are the highest in “installation cost”, followed by “operation cost” and finally “connection rate”.

FIG. 7 shows a configuration example of the communication characteristic table 114.
The communication characteristic table 114 manages information related to communication characteristics for each communication type. The communication characteristic information includes, as items, a communication type 601, an inter-link communication success rate 602, an inter-link communication distance 603, a base station capacity 604, and a base station arrival link number 605.

The communication type 601 is as described above.
In the inter-link communication success rate 602, the success probability of communication in one link configured between terminals or between a terminal and a base station according to the communication type 601 is registered.
In the inter-link communication distance 603, a communicable distance in one link configured by the communication type 601 is registered.

In the base station capacity 604, the maximum number of terminals that can be accommodated by one base station used in the communication type 601 is registered.
In the base station arrival link number 605, the number of links necessary for a terminal based on the communication type 601 to communicate with the base station is registered. For example, the minimum number of links necessary for the terminal to communicate with the base station may be registered in the base station reaching link number 605. When the communication type 601 is “3G / LTE communication”, normally, the terminal can directly communicate with the base station, and therefore the base station reachable link number 605 is “1”. In a case where the communication type 601 is “multi-hop wireless communication” and the area cannot communicate directly with the base station, for example, the base station reachable link count 605 is “100”.

  Next, a specific example of the process for determining the communication type of the terminal (S202 in FIG. 3) will be described with reference to the flowchart in FIG.

  The design support apparatus 101 acquires a terminal installation plan in the final year of the processing target in the target area (S701). For example, the design support apparatus 101 sets each area divided into “500 m × 500 m” as a target area. Then, the design support apparatus 101 executes the following process for each terminal in the target area.

  The design support apparatus 101 determines whether the communication type of the terminal can be determined as one based on the physical conditions such as the house information 306 where the terminal is to be installed, the line information 307, and the geographical information. (S702). For example, when the house information 306 is “high-rise apartment”, the design support apparatus 101 may determine the communication type of the terminal as “PLC”. This is because in a high-rise apartment, wireless communication tends to become unstable due to a shielding object such as a wall. For example, when the house information 306 is “detached” in a mountain village, the design support apparatus 101 may determine the communication type of the terminal as “3G / LTE communication”. This is because, in the case of a detached house in a mountain village, other communication types cannot be used, such as FTTH is not laid or the distance to the adjacent building (terminal) is long. If the communication type of the terminal can be determined as one (S702: YES), the design support apparatus 101 proceeds to S706.

  When the communication type of the terminal cannot be determined as one (S702: NO), the design support apparatus 101 narrows down an appropriate communication type based on the connection rate and the installation operation cost (S703). For example, the design support apparatus 101 narrows down the communication types that minimize the installation operation cost within a range where the connection rate does not decrease (or within a range where the required connection rate is not less than 503). Normally, when “multi-hop wireless communication” is selected as the communication type, the installation and operation costs tend to be minimized. This is because a multi-hop wireless communication terminal usually requires little operating cost. Furthermore, in the case of multi-hop wireless communication, since a large number of terminals are connected to one base station by a multi-hop communication method, a network can be constructed with a smaller number of base stations compared to other communication types. It is.

  If the communication type of the terminal can be narrowed down to one in S703 (S704: YES), the design support apparatus 101 determines the communication type of the terminal as one and proceeds to the process of S706.

  When the communication type of the terminal cannot be narrowed down to one in S703 or when a special condition is imposed on the terminal (S704: NO), the design support apparatus 101 decides on one communication type as an exception process. Then (S705), the process proceeds to S706. For example, the design support apparatus 101 has been narrowed down to multi-hop wireless communication, but the communication type is determined to be 3G / LTE communication due to the distance to other terminals, and the installation and operation costs increase, but the connection The PLC is determined based on the priority of the rate.

  As S706, the design support apparatus 101 determines whether or not the processing has been completed for all the terminals in the target area (S706). If there is an unprocessed terminal (S706: NO), the unprocessed terminal The process after S702 is executed, and if there is no unprocessed terminal (S706: YES), the process is terminated (END). Here, the communication type of the target area may be determined based on the communication type determined for each terminal. For example, the communication type of the most terminals in the target area may be set as the communication type of the target area.

  Next, a specific example of the process (S203 in FIG. 3) for calculating the installation and operation costs of terminals and the like in the target area in the target year will be described.

  The design support apparatus 101 refers to the communication cost information table 107 shown in FIG. 5 and calculates the installation and operation costs of terminals and the like in the target area in the target year.

  For example, according to the communication cost information table 107, the installation cost 403 per terminal in 3G / LTE communication is “10,000 yen”, and the operation cost 404 per terminal month is “3,000 yen”. There is no base station installation cost 405 and base station operation cost 406 in 3G / LTE communication. This is because these costs are usually borne by the service provider of 3G / LTE communication.

  For example, in the case of multi-hop wireless communication, the installation cost 403 per terminal is “10,000 yen”, the operation cost 404 per terminal is “0 yen”, and the installation cost 405 per base station is The operating cost 406 per month for “100,000 yen” is “3,000 yen”.

  For example, in the case of long-distance wireless communication, the installation cost 403 per terminal is “10,000 yen”, the operation cost 404 per terminal is “0 yen”, and the installation cost 405 per base station is “ 100,000 yen ", and the operating cost 406 per base station is" 3,000 yen ".

  The design support apparatus 101 adds the expenses shown in the communication operation information table 107 to the number of terminals and base stations that are planned to be installed in the target area in the target year, so that the terminals in the target area of the target year, etc. Installation and operation costs can be calculated.

Next, a specific example of the process for calculating the connection rate (S204 in FIG. 3) will be described.
The design support apparatus 101 refers to the communication characteristic information table 114 shown in FIG. 7 and calculates the connection rate in the target area in the target year.

  For example, according to the communication characteristic information table 114, in the case of 3G / LTE communication, the inter-link communication distance 603 where the inter-link communication success rate 62 is “98%” or more is “1.5 km”. In the case of 3G / LTE communication, the terminal directly communicates with the base station. Therefore, for example, when a base station exists in a target area of “500 m × 500 m”, almost all terminals in the target area can communicate with the base station, so the connection rate of the target area is “98% " In the case of long-distance wireless communication, since the terminal directly communicates with the base station, the connection rate of the target area can be calculated by the same method as described above.

  For example, according to the communication characteristic information table 114, in the case of multi-hop wireless communication, the inter-link communication distance 503 where the inter-link communication success rate 602 is “98%” or more is “30 m”. In the case of multi-hop wireless communication, there are terminals that communicate directly with the base station. Some terminals communicate with the base station via other terminals, and the number of terminals that pass through the terminals may be different. In addition, a terminal that is 30 m or more away from an adjacent terminal cannot communicate or the communication success rate decreases. The communication success rate in such a case is calculated as follows, for example.

The success rate of the terminal that communicates directly with the base station is “98%” of the inter-link communication success rate 602. The success rate of terminals that communicate with the base station via other terminals is:
Success rate = Inter-link communication success rate ^ Number of links reached by base station (Equation 1)
May be calculated as Or the success rate is
Success rate = ((1-link communication error rate) ^ number of retransmissions between links) × number of links reached by base station (Expression 2)
May be calculated as

  In multi-hop wireless communication, a terminal that cannot directly communicate with a base station has a success rate of “0%” when it cannot communicate with an adjacent terminal. The average value of the success rates calculated for each terminal in the target area may be used as the connection rate of the target area. The same applies to other target years.

  Next, a specific example of the process for determining whether or not the connection rate is equal to or higher than the required connection rate 503 (S205 in FIG. 3) will be described.

  According to the calculation condition table shown in FIG. 6, the required connection rate 503 is “80% or higher” in FY2013, “83% or higher” in FY2014, and “99% or higher” in 2025. Therefore, the design support apparatus 101 compares the connection rate of the target area in the target year calculated above with the required connection rate 503 in the target year, and determines whether or not the connection rate is equal to or higher than the required connection rate 503. There is a need.

  Next, an example of a process for generating an installation plan in which base stations and / or relays are added so that the connection rate in FIG. 3 is equal to or higher than the required connection rate 503 will be described with reference to the flowchart in FIG. 9. Here, processing of the target area whose communication type is determined as “multi-hop wireless communication” will be described.

  The design support apparatus 101 further divides the target area into subareas (S801). For example, the design support apparatus 101 divides a target area of “500 m × 500 m” into subareas of “50 m × 50 m”.

  The design support apparatus 101 determines whether or not there is a terminal in which communication by multi-hop wireless communication is impossible (or the communication success rate is less than a predetermined value) in the subarea (S802). For example, the design support apparatus 101 may set a terminal in which no other terminal or base station exists within a radius of 30 m as a terminal incapable of communication.

  If there is a terminal incapable of communication in the subarea (S802: YES), the design support apparatus 101 adds one repeater to an appropriate position in the subarea (S803), and proceeds to the process of S804. If there is no terminal that cannot communicate in the sub-area (S802: NO), the design support apparatus 101 proceeds to the process of S804.

  In S804, the design support apparatus 101 determines whether or not the processing in S802 and S803 has been completed for all subareas (S804). If there is an unprocessed subarea (S804: NO), the processing in S802 is performed. Return to. If no unprocessed subarea remains (S804: YES), the design support apparatus 101 proceeds to the process of S805.

  In S805, the design support apparatus 101 extracts adjacent subareas for the target subarea (S805). Then, the design support apparatus 101 determines whether or not the target subarea can communicate with the adjacent subarea (S806). If communication with an adjacent subarea is not possible (S806: NO), the design support apparatus 101 adds one base station to an appropriate position (S807), and proceeds to the process of S808. If communication with an adjacent subarea is possible (S806: YES), the design support apparatus 101 proceeds to the process of S808.

  In S808, the design support apparatus 101 determines whether or not this process has been completed for all the subareas (S808). If there is an unprocessed subarea (S808: NO), the process returns to S806. When no unprocessed subarea remains (S804: YES), the design support apparatus 101 ends the process (END).

  Next, a specific example of the process for calculating the installation operation cost (S207 in FIG. 3) will be described with reference to FIGS.

  FIG. 10 is a table showing communication types applicable to the target area, and FIG. 11 is a table showing installation and operation costs when the communication type is applied to the target area.

  For example, it is assumed that the first area 901 is a central area where houses are densely populated, the second area 902 is a suburban area where houses are moderately present, and the third area 903 is a mountain village where sparsely populated houses are present.

  The first area 901 and the second area 902 are divided into cases where base station operating costs are incurred (911, 913) and cases where they are not incurred (912, 914). This is because, for example, if you have your own base station line, you will not incur base station operating costs, but if you use another company's line, such as a telephone company, you may incur base station operating costs. It is.

  As shown in FIG. 11, the design support apparatus 101 performs appropriate communication for each of the areas 901 to 903 when the terminal installation planned density is high (921) and when the terminal installation planned density is low (922). The type and installation operation cost are calculated and displayed. The design support apparatus 101 calculates and displays an appropriate communication type and installation operation cost in a special environment such as a high-rise apartment 923 for each of the areas 901 to 903.

  The user can grasp the scale of the designed sensor network by confirming the specific installation and operation costs as shown in FIG.

  Next, an example of outputting information related to the calculation result in S209 of FIG. 3 will be described with reference to FIGS.

  FIG. 12 is an example of a graph 1100 representing the cost per terminal for each communication type in each area. In the graph 1100, the vertical axis represents the installation and operation cost per terminal, and the horizontal axis represents each communication type in each area. In the graph 1100, a bar graph 1112 indicates an installation cost per terminal corresponding to the communication type, and a bar graph 1113 indicates an operation cost per terminal corresponding to the communication type. These costs are calculated based on the installation and operation costs calculated for each area (see FIG. 11). By checking the graph 1100, the user can visually grasp the difference in cost for each communication type in each area.

  FIG. 13 is an example of a graph 1200 showing the cost for each year in each area. In the graph 1200, the vertical axis indicates the installation and operation cost for each year in a certain area, and the horizontal axis indicates the year. In the graph 1202, the bar graph 1202 shows the installation cost of the terminal in the target year, and the graph 1203 shows the operation cost of the terminal in the target year. These costs are also calculated based on the installation and operation costs calculated for each area (see FIG. 11). By checking the graph 1200, the user can visually grasp the change in the installation and operation costs for each year.

  Next, an example of displaying an installation plan of terminals and the like in an area will be described with reference to FIGS.

  FIG. 14 is an example of a map 1300 showing an installation plan of terminals and the like in 2013, which is the initial stage of the plan. FIG. 15 is an example of a map 1400 of an installation plan for terminals and the like in FY2025, which is the final stage of the plan.

  For example, the design support apparatus 101 displays a map when a terminal, a base station, a relay machine, and the like are installed in the target area. As shown in FIG. 14, it is a plan that only some terminals are installed in the initial stage, but as shown in FIG. 15, almost all terminals are installed in the final stage.

  The map of FIG. 14 (FIG. 15) shows that the road 1301 (1401) and the road 1302 (1402) intersect. In the map of FIG. 14 (FIG. 15), the area is divided into four areas 1305, 1306, 1307, 1308 (1405, 1406, 1407, 1408) by vertical lines 1303 (1403) and horizontal lines 1304 (1404). A black circle 1309 (1409) indicates a terminal. A white circle 1310 (1410) indicates a base station. A hatched circle 1311 (1411) indicates a repeater.

  According to the map shown in FIG. 14, the number of terminals is small in the initial stage plan, and it is necessary to install a large number of base stations and repeaters for multi-hop wireless communication in order to satisfy the connection rate. I understand. The user can see from the map in FIG. 15 that in the final stage plan, the number of terminals is large, so that the connection rate can be satisfied even if the number of base stations and relay stations is small. In addition, it can be seen that the user needs to change the installation position of the base station from the maps of FIGS. 14 and 15. This is because the location of the base station is changed in accordance with the increase in the number of terminals, thereby improving the connection rate and suppressing the installation and operation costs.

  Hereinafter, a specific example of processing for installing a base station and / or a repeater in the target area will be described with reference to a map 1500 in FIG. Black circles, white circles, and the like in FIG. 16 are as described in FIG.

  For example, the design support apparatus 101 divides the target area 1501 into lattice-shaped subareas 1510. Then, the design support apparatus 101 determines whether there is a terminal in an adjacent subarea (that is, a certain terminal can communicate with another terminal). In order to improve the connection rate of the target area 1501, the design support apparatus 101 is installed with two repeaters 1511 and 1512, for example. For example, the design support apparatus 101 installs one base station 1513 in order to improve communication efficiency.

  The design support apparatus 101 displays the location of the terminal on the map and also displays the subarea, so that the user can visually grasp the validity of the sensor network design plan.

  According to the present embodiment, by using the design support apparatus 101, the user can make an appropriate sensor network design plan considering long-term communication quality and cost. In addition, by using the design support apparatus 101, the user can know a communication method that can suppress long-term installation and operation costs as much as possible while satisfying the connection rate required for each year in each area.

  The above-described embodiments of the present invention are examples for explaining the present invention, and are not intended to limit the scope of the present invention only to the embodiments. Those skilled in the art can implement the present invention in various other modes without departing from the spirit of the present invention.

  For example, the design support apparatus 101 may generate a sensor network design plan using only the design conditions specified by the input / output apparatus 120. For example, the design support apparatus 101 may generate a sensor network design plan using only information that the user is permitted to access. For example, the design support apparatus 101 may calculate only the design operation cost, calculate only the installation position of the terminal, or calculate only the communication type.

  For example, the design support apparatus 101 may calculate the design operation cost and the like assuming that terminals are concentrated in the first year. In this case, the design support apparatus 101 does not calculate the design operation cost for each fiscal year, but performs the processing shown in FIG. The design support apparatus 101 may calculate the design operation cost assuming that the terminal is installed in a certain fiscal year, with the fiscal year behind. This is because in multi-hop wireless communication, since the connection rate increases by increasing the terminal installation planned density, it is also assumed that terminals and the like are installed concentrically by moving forward or backward in the fiscal year.

DESCRIPTION OF SYMBOLS 10,101 ... Design support apparatus 11 ... Communication system selection part 12 ... Connection rate calculation part 13 ... Plan correction part 14 ... Cost calculation part 15 ... Display processing part 16 ... Memory | storage part

Claims (11)

First plan information including information on communication terminals scheduled to be installed in a predetermined area by the first time point, and communication terminals scheduled to be installed in the predetermined area by a second time point after the first time point Storage unit for storing second plan information including information on
A sensor network comprising: a communication method selection unit that selects a communication method for a communication terminal in the predetermined area to transmit data to a server from communication methods prepared in advance based on the second plan information. System design support device.
The sensor network system according to claim 1, wherein the communication method selection unit selects a communication method in the predetermined area based on an installation density of the communication terminal in the predetermined area included in the second plan information. Design support equipment.
When the communication method selected based on the second plan information for the predetermined area is applied to the first plan information, it is determined whether or not the first design condition for the first time point is satisfied 3. The sensor network system according to claim 1, further comprising a plan correction unit that corrects the first plan information so as to satisfy the first design condition when the first design condition is not satisfied. Design support equipment.
The first design condition includes a ratio of communication terminals that can transmit data to the server among all communication terminals in the predetermined area when the selected communication method is applied to the predetermined area. 4. The sensor network according to claim 3, wherein the connection rate calculated based on the first plan information is equal to or higher than a required connection rate required at the first time point. System design support device.
The sensor network system according to claim 4, wherein the communication system prepared in advance includes a multi-hop wireless communication system in which the communication terminals transfer the data to each other and transmit the data to the server. Design support equipment.
When the selected communication method is the multi-hop wireless communication method and the connection rate calculated based on the first plan information is less than the required connection rate, the plan correction unit The sensor network system design support apparatus according to claim 5, wherein correction is performed to add a relay apparatus that relays data from the communication terminal to the first plan information so as to be equal to or higher than the required connection rate.
The relay apparatus and the communication scheduled to be installed by the second time point in the predetermined area when the selected communication method is applied based on the corrected first plan information and the second plan information The sensor network system design support apparatus according to claim 6, further comprising a cost calculation unit configured to calculate a cost related to the terminal.
Costs related to the relay device and the communication terminal include costs required to install the relay device and the communication terminal and costs required to operate the relay device and the communication terminal based on the selected communication method. The design support apparatus of the sensor network system according to claim 7.
9. The design support for a sensor network system according to claim 7 or 8, wherein the cost calculation unit calculates a cost when each communication method is applied when two or more communication methods can be selected in the communication method selection unit. apparatus.
The sensor network system design support apparatus according to claim 9, further comprising a display processing unit that displays costs in a case where the respective communication methods are applied in a comparable manner.
First plan information including information on communication terminals scheduled to be installed in a predetermined area by the first time point, and communication terminals scheduled to be installed in the predetermined area by a second time point after the first time point 2nd plan information including information about
A sensor network system for executing, by a computer, a communication terminal in the predetermined area to select a communication method for transmitting data to a server from communication methods prepared in advance based on the second plan information Design support method.

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