JP2009081790A - Communication system, center device and terminal device used in the communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make uniform power consumption in terminal devices of a communication system formed by connecting a plurality of terminal devices. <P>SOLUTION: In the communication system configured by connecting the plurality of terminal devices 20 to a center device 30 over multi-stages, a terminal device 20(3) in which charged power of a solar cell 40 is lacked, calls a route change to a closest lower-layer terminal device 20(8) being routed to the terminal device 20(3) itself. The terminal device 20(8) designates a closest higher-layer terminal 20(4) and requests a change permission to the center device 30, and the center device judges whether the terminal device 20(4) is suitable or not by referring to charged power and an electric field strength of the terminal device 20(4) and information about terminal devices of lower layers in connection. When permitted, the terminal device 20(8) changes the route. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  INDUSTRIAL APPLICABILITY The present invention is a communication system configured by connecting terminal devices serving as slave units each having a power generation device based on natural energy in multiple layers in a hierarchical structure with the terminal device serving as a master unit at the top, and used in the communication system The present invention relates to a center device and a terminal device.

For example, a terminal device that is a parent device and a terminal device that is a child device are connected so as to be capable of wireless communication with each other, and data such as gas usage collected by the child device is transmitted to the center device via the parent device, A remote management system that collectively manages the usage state of each gas meter by a center device is known.
In this remote management system, for example, the slave unit is disposed in each home etc. integrally with a gas meter, and a master unit that manages a plurality of slave units is connected to each slave unit so as to be capable of wireless communication. It receives commands from the center device via the master unit and performs operations such as transmission of measurement data.

  Since communication between the master unit and the specified slave unit is performed via other slave units connected in multiple stages, the number of the slave units and the slave units connected to the slave units is different for each slave unit. Since the slave unit consumes a large amount of power for communication, when a dry battery or the like is used as a power source, the battery life is quickly reached and replacement is required. Therefore, if the batteries of the slave units are replaced all at once, there is a problem that it is necessary to match the batteries that have reached the end of their life first, and it takes time and effort to replace the batteries for each individual slave unit. Although the dry battery can be used for a long period of about 10 years, the replacement of the battery is complicated in any case. Therefore, it is preferable to provide a small power generator in each slave unit.

  Therefore, in recent years, due to circumstances such as conservation of the natural environment, it is recommended to use a power generation system using natural energy, especially an invention system using solar cells. In remote management systems, instead of conventional batteries, The use of solar cells has been performed.

FIG. 7 is a block diagram schematically showing a communication system used for a remote management device, for example, which is composed of a parent device and a child device, each of which is a conventional terminal device, although it is not described in the patent literature. . Here, the solar cell 40 is used as a drive power source of the slave unit.
As shown in the figure, a plurality of child devices (being terminal devices) 20 are connected to the parent device (being a terminal device) 10 in a multi-stage form with a kind of hierarchical structure with the parent device 10 as a vertex. In the illustrated example, a slave unit (also simply referred to as a terminal device) 20 (1) and 20 (2) is directly connected to a master unit (also referred to as a master terminal device) 10, and the slave unit 20 (1) and slave unit 20 ( 2) On the lower side of the slave unit 20 (3), 20 (4), 20 (5) respectively, and on the lower side of the slave unit 20 (3), slave units 20 (6), 20 (7), 20 (8), and the slave unit 20 (9) is connected to the lower stage of the slave unit 20 (5).

In this configuration, for example, an instruction or command transmitted from the center device 30 (also simply referred to as a center) to a specific child device, for example, the child device 20 (7) via the parent device 10 via the public line or the dedicated line network NT. Is transmitted from the master unit 10 to the slave unit 20 (7) via the slave unit 20 (1) and the slave unit 20 (3), and the measurement data and communication text from the slave unit 20 (7) are The data is transmitted to the center device 30 through the reverse path.
Accordingly, here, the slave units 20 (1) and 20 (3) in the connection path between the slave unit 20 (7) and the master unit 10 are connected between the slave unit 20 (7) and the master unit 10 or the center device 30. Every time communication occurs, an operation for sending and receiving data and communication text is performed.
That is, the slave unit 20 (3) is in the connection path of the three slave units 20 (6) to 20 (8), while the slave unit 20 (4) has no slave unit in the lower hierarchy. . Therefore, in the illustrated example, the power consumption of the slave unit 20 (3) is greater than that of the slave unit 20 (4). Therefore, in order to secure a power generation amount commensurate with this, the solar cell 40 having a larger power generation amount than that of the child device 20 (4) is attached to the child device 20 (3).

Moreover, when generating electric power using not only a solar cell but natural energy, such as a wind force, a wave force, and a geothermal, there exists a problem that electric power generation amount is not stabilized. In particular, for example, in the case of using a solar cell, since the amount of power generation varies greatly due to the influence of the weather and the surrounding environment, and the difference between day and night, a storage battery is provided in order to operate the terminal device (slave unit) stably. However, it is necessary to have a capacity assuming that the maximum power is used, and a solar cell having a sufficient margin for power generation capacity to generate a sufficient amount of electricity.
Therefore, the conventional communication system using solar cells has a problem that costs are increased.

  In addition, there is a problem that it is not easy to predict the maximum power consumption for each slave unit, particularly in a slave unit such as the slave unit 20 (3) where access is concentrated.

  An object of the present invention is, for example, in a communication system configured by a power generation device using a master unit and natural energy, such as a remote management system, for example, a terminal device serving as a plurality of slave units including a solar cell as a drive power source. By equalizing the power consumption of each slave unit as much as possible and optimizing the power consumption of the entire system, the power generation device and power storage unit capacity of each slave unit is equalized and saved, reducing costs. It is to let you.

The invention of claim 1 is a terminal device used in a communication system configured by a terminal device in which a center device and a plurality of terminal devices are connected in multiple stages, wherein a power generator using natural energy, and a charge amount of the power generator Means for calculating, means for detecting the communication field strength of the terminal device, means for transmitting the charge amount information and communication field strength data to the center device, and the terminal device when the charge power amount is a predetermined value or less And a means for transmitting a signal for prompting a route change to another terminal device for which the route has been set.
According to a second aspect of the present invention, in the terminal device according to the first aspect, when a signal prompting a route change is received from another terminal device, a means for transmitting a connection route change request to the center device, from the center device When a connection route change instruction is received, a means for changing the connection route to the connection route is provided.
According to a third aspect of the present invention, in the terminal device according to the second aspect, the means for transmitting the connection path change request transmits the terminal device information as the connection partner candidate based on the electric field strength information to the center device. Features.
The invention of claim 4 is a center device used in a communication system configured by a terminal device in which a center device and a plurality of terminal devices are connected in multiple stages, and the charging power amount of each terminal device transmitted from each terminal device, Storage means for storing field strength data and lower-level connection terminal device data, when a connection route change request is received from the terminal device, included in the connection route change request based on the field strength data, the charging power amount and the lower-level connection terminal device data Means for determining whether or not the change destination terminal device can be changed, and when the change destination is determined to be changed, the terminal device is instructed to change the connection route to the designated connection route change destination terminal device. And
According to a fifth aspect of the present invention, there is provided a communication system comprising the terminal device according to any one of the first to third aspects and the center device according to the fourth aspect.

(Function)
In this communication system, a power generation device using natural energy is provided in a terminal device serving as an individual slave unit, and is individually stored. If there is a risk that the charge amount of a specific terminal device (child device) will be insufficient, relaying from other child devices will be suppressed or stopped, and the terminal device (child device with a margin for other charge amount) ) To change the connection route.
Further, the connection route is changed by designating the connection route change destination terminal device in the center device based on the charging power information and communication field strength information of the terminal device collected from each terminal device. At the time of designation, the suitability of the change destination terminal device is determined from the charge amount information of the designated destination terminal device, the electric field strength data, and the subordinate device information. The connection path change is registered in each terminal device serving as a child device, a terminal device serving as a parent device, or a center device connected to the parent device. After registration, all communications in the communication system are performed through the changed connection path.

According to the present invention, when there is a possibility that the charge amount of a terminal device serving as a specific slave unit is insufficient, the terminal device serving as an individual slave unit is changed to change the connection path to a terminal device that requires another charge amount. Electric power generated every time can be efficiently used without excess or deficiency in the entire communication system.
Therefore, even when the terminal devices (slave devices) are hierarchically arranged in multiple stages, the power generation capacity and the charge amount of each terminal device (slave device) can be made uniform. For this reason, it is possible to reduce the capacity of the power generation device and the like, and it is possible to reduce the cost as compared with a conventional similar communication system.
In addition, when changing the connection path, determine the suitability of the change destination terminal device from the amount of charge of the connection destination terminal device, the electric field strength in communication with the connection destination terminal device, and the subordinate device information. Since the route is changed, a stable system can always be realized even if the power generation environment or communication status of each terminal device changes.

An embodiment of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a block diagram of a terminal device used in a communication system according to an embodiment of the present invention.
The terminal device 20 controls the entire terminal device 20, for example, a main control unit 21 made of a microcomputer, a wireless unit 22 for performing wireless communication with another terminal device 20 or the terminal device 10 serving as a parent device, and the like. I / O interface 23 for connection with other devices, solar cell 40 for converting solar energy into electric energy, and charge amount for controlling the charge amount while controlling charge of the storage battery for storing generated power The measuring unit 25 includes a rechargeable battery or capacitor 26 that is a power storage unit that stores electric power generated by the solar battery 40, and an electrolytic strength measuring unit 28.

  The terminal device 20 stores the electric power generated by the solar battery 40 in the power storage unit (rechargeable battery or capacitor) 26, and measures the current power storage amount by the output current or voltage of the power storage unit 26 in the charge amount measurement unit 25. The main control unit 21 compares a predicted power consumption amount and a charge amount of the terminal device to be described later, and maintains the connection path as long as the charge amount exceeds the predicted power consumption amount. The process for changing the connection route is performed. The electric field strength measuring unit 28 measures the electric field strength from the received signal, sends the electric field strength information to the main control unit 21, and stores it in the memory.

FIG. 2 is a diagram schematically showing a remote monitoring system according to an embodiment of the communication system of the present invention using the terminal device as a slave unit, and the system configuration itself is the same as the conventional one already described. Since they are basically the same, the same reference numerals are given to the same parts.
That is, a plurality of terminal devices (child devices) 20 in the parent device 10 have the parent device 10 as the apex, and the first-stage terminal devices 20 (1) and 20 (2) directly connected to the parent device 10 and the terminal The second stage terminal devices 20 (3), 20 (4), 20 (5) and the terminal devices 20 (3) to 20 (5) connected to the device 20 (1) and the terminal device 20 (2) The third-stage terminal devices 20 (6) to 20 (9) to be connected are connected and arranged in a three-stage hierarchical structure. In addition, each terminal device 20 is provided with a power generator using natural energy, that is, a solar cell 40.

  As already described, in this configuration, for example, an instruction or command issued from the center device 30 to a specific terminal device, for example, the terminal device 20 (8), is sent from the parent device 10 to the terminal device 20 (1), the terminal. The data is transmitted to the terminal device 20 (8) via the device 20 (3), and the measurement data and the communication text from the terminal device 20 (8) are transmitted to the center device 30 along the reverse path.

Thus, when the terminal devices 20 are arranged and connected in multiple stages in the hierarchical structure shown in FIG. 2, the power consumption may vary greatly among the individual terminal devices.
Therefore, in this embodiment, when it is determined that the predicted power consumption in a specific terminal device exceeds the charge power amount, the connection path via the specific terminal device is changed to another charge amount (power storage amount). It is possible to change to a terminal device with a margin.

In addition, when changing the connection path, the charge amount information and electric field strength data of each terminal device are stored in the data server of the center device 30, and the center device 30 is a data representing the charge amount for each of the terminal devices 20. Whether or not the route can be changed based on the charging current level, the electric field strength data, and the slave unit (subordinate slave unit) information under the control of the terminal device 20 (referred to as “subordinate connected terminal device data”). I do.
Therefore, as shown in FIG. 2, the center device 30 includes a field strength reference table T1, a charging current amount reference table T2, and a subordinate device information reference table T3 in the data server.

  Here, the electric field intensity reference table T1 stores a comparison table between the electric field intensity data and an index as data used when the path change is determined. In the illustrated example, for example, the electric field strengths 9 and 10 correspond to the index 3. Similarly, the charge current amount reference table T2 stores a comparison table between data representing the charge current level and an index used for the above determination. In the illustrated example, both charging current levels 10 and 9 correspond to an index of 3. Further, in the subordinate child device information reference table T3, a terminal device serving as an upper child device or parent device as viewed from the subordinate terminal device, that is, the specific child device, that is, a certain child device and its communication destination terminal device information are paired. Stored.

The center device 30 calculates a route determination level according to the following equation (1) using the electric field intensity reference table T1 and the charging current amount reference table T2 for the route change destination terminal device, and the subordinate device information reference table based on the calculated value. By referring to T3, it is determined whether or not the route change is appropriate.
That is, path change determination level f (x) = electric field strength level point + charge level point (formula 1).

FIG. 3 shows the route change determination level f (x) and the determination contents. That is, it is a list showing the route change determination level indexed and the contents determined from the subordinate device information reference table T3.
As shown in the figure, when the route change determination level f (x) of the partner terminal device to be changed from the terminal device serving as the child device is 3 or less, refer to the subordinate child device information reference table T3. If the slave terminal device does not have a slave device under its control, it is determined to change the route. When the route change determination level f (x) is 4, it is determined to change the route (route) if the number of subordinate slaves to be changed is one or less. Similarly, when f (x) is 5, there are 2 or less subordinate slave units, and when f (x) is 6, there are 3 or less subordinate slave units. In each case, it is decided to change the route. If the above criteria are not met, the terminal device is not changed.

  In the present embodiment, each terminal device 20 transmits the electric field strength of the signal from the communication partner measured by the electric field strength measuring unit 28 to the center device 30 autonomously or in response to an instruction from the center device 30. 30 is indexed based on the electric field strength reference table T1 based on the electric field strength information acquired from each terminal device 20.

Next, collection of basic data (electric field strength data and charging current amount of each terminal device) performed by the center device 30 for determination of path change, such as acquisition of the electric field strength, will be described.
(1) Acquisition of electric field strength of each terminal device by the center device As a premise of this processing, each terminal device communicates electric field strength with other peripheral terminal devices acquired by a communication operation performed at the time of inter-terminal communication or when performing edge registration ( Value).
FIG. 4A shows a procedure in which the terminal device attaches the field strength information stored in its own database as an accompanying data to the center device at the time of reporting and transmits it to the center device. FIG. 4B shows the field strength information based on a request from the center device. Shows a procedure for transmitting to the center device.

  That is, when the terminal device 20 autonomously transmits its own electric field strength data, as shown in FIG. 4A, the terminal device 20 transmits the electric field strength information data to the parent terminal device (parent device) 10 in accordance with the signal issue. (S101) The parent terminal device 10 transfers the information to the center device (S102). The center device 30 stores the acquired terminal field strength information of the terminal device 20 (S103).

  When the terminal device 20 transmits its own electric field strength data based on a request from the center device 30, as shown in FIG. 4B, the center device 30 first sends a field strength notification request to the parent terminal device 10 (S201). The parent terminal device 10 transfers it to the managed terminal device 20 (S202). The terminal device 20 that has received the notification request from the center device 30 transmits its electric field strength information to the parent terminal device 10 based on this (S203), and the parent terminal device 10 transfers it to the center device 30 ( S204). The center device 30 stores the acquired terminal field strength information of the terminal device 20 (S205).

(2) Regarding acquisition of charging current amount of each terminal device by center device FIG. 5A shows a procedure in which the terminal device assigns its own charging current amount as accompanying data to a message and sends it to the center device at the time of reporting. The procedure for transmitting the charging current amount to the center device based on the request from the center device will be described.
As a premise of this process, the terminal device 20 detects the power generation amount of its own solar cell 40 (S301) and calculates the predicted power consumption of the terminal device 20 (S302). Specifically, for example, the terminal device 20 Taking (3) as an example, the main control unit 21 of the terminal device 20 (3) to which the terminal devices 20 (6) to 20 (8) are connected in the lower hierarchy, for example, from the past data, the terminal device 20 ( 6) to 20 (8), the total power consumption is calculated by adding the power consumption required for communication, and the power consumption obtained by adding a predetermined margin to the calculated power consumption is the own predicted power consumption, that is, the own terminal consumption. Calculate as energy. The difference between the self-terminal power consumption amount and the solar cell power generation amount is set as the charge amount, and the information is added as the charge amount information (here, charge current amount information) to the notification information and transmitted to the parent terminal device 10 ( S303).
The parent terminal device 10 transmits the notification information + charge amount information to the center device 30 (S304), and the center device 30 stores the charge amount information in the storage device (S305).

FIG. 5B is a flowchart for explaining a processing procedure when the terminal device 20 notifies its own charge amount in response to a request from the center device 30.
The terminal device 20 detects the power generation amount of its own solar cell 40 (S401), calculates the power consumption of its own terminal device 20 (S402), and stores the charging current amount information in its own database. deep. In this state, when a charge amount notification request for the terminal device 20 is first transmitted from the center device 30 to the parent terminal device 10 (S403), the parent terminal device 10 transmits the request under its own management. It transmits to the terminal device 20 (S404). When receiving the request, the terminal device 20 reads the charging current amount information from the database and transmits it to the parent terminal device 10 (S405). The parent terminal device 10 transfers the charging current amount information to the center device 30 (S406), and the center device 30 stores the acquired terminal charging current amount information in the storage device (S407).
As described above, the center device 30 collects terminal field strength information and charging current amount information of each terminal device 20 and prepares for the route change processing.

Next, the route change process will be specifically described.
In the present embodiment, the terminal device 20, for example, the terminal device 20 (3) compares its own predicted power consumption obtained as described above with the current charge amount. As a result of the comparison, when the current charge amount exceeds the predicted power consumption, the connection path is maintained as it is, and conversely, when the current and current charge amount for a certain period of time are lower than the predicted power consumption, that is, When the amount of charge is less than a predetermined level, here zero or less, a signal for prompting a route change is transmitted to the terminal devices connected immediately below. The terminal device that has received the signal is the designation information of the change destination (candidate) terminal device in that case (change destination terminal device information is selected based on, for example, the electric field strength information acquired by each terminal device through a communication operation). Is sent to the center device 30 via the parent terminal device 10.

  The center device 30 calculates the route change determination level f (x) based on the charging current amount data of the terminal device designated as the change destination and the communication electric field strength data between the terminal devices, and see this value and the subordinate device information. With reference to the table T3, it is determined whether or not the change is appropriate. If it is determined to be appropriate, it instructs to change the route to the designated terminal device. In this case, the number of slave units (terminal devices) subordinate to the terminal device to be changed and the number of slave units (terminal devices) subordinate to the terminal device that made the change request are added to the number of subordinate slave units. The

FIG. 6 is a route change flowchart according to the first embodiment for changing the route.
First, as a premise, all the terminal devices (slave devices) belonging to this communication system acquire communication electric field strength information with neighboring terminal devices as already described (S501), and the stored solar cell power generation The amount is detected (S502), and the predicted power consumption of the terminal device is calculated (S503). The charging current amount information and the electric field strength information obtained from these pieces of information are obtained at the time of issue or the center. The parent terminal device 10 is notified (transmitted) in response to a request from the device 30 (S504). The parent terminal device 10 transfers the received information to the center device 30 (S505). The center device 30 stores the acquired information (data) in the storage device (S506).

  Here, for example, the solar cell power generation amount of the terminal device 20 (3) having the terminal device 20 (8) below the connection hierarchy is equal to or less than the predicted power consumption of the own terminal device (solar power generation ≦ the predicted power consumption of the own terminal device). When this is the case, the terminal device 20 (3) transmits a signal for prompting the route change to the terminal device 20 (8) connected at the nearest lower level. The terminal device 20 (8) that has received the signal is a terminal device 20 (4) (solar power generation ≦ predicted power consumption of its own terminal device) that is previously determined as a route change candidate for the parent terminal device 10, The connection route change request is transmitted including the designation information that designates (S507). The parent terminal device 10 transfers this request to the center device 30 (S508). Upon receiving this request, the center device 30 reads the terminal electric field strength data and the charging current amount information of the terminal device 20 (4) from the database, and based on these data, the route change determination level f (x) (= electric field strength). (Level point + charge level point) is calculated. With reference to this calculation result and the subordinate child device information reference table T3, it is determined whether or not the terminal device 20 (4) as the connection path change destination child device of the terminal device 20 (8) is suitable. Here, since the terminal device 20 (4) has no subordinate child device (terminal device), the route change is determined according to the list of FIG. 3 (S509).

  The center device 30 sends a route change instruction to change the route to the terminal device 20 (8) from the terminal device 20 (3) to the terminal device 20 (4) to the parent terminal device 10 (S510). Sends a route change request to the terminal device 20 (8) through the route of the terminal device 20 (2) and the terminal device 20 (4) (S511).

  The terminal device 20 (8) that has received the route change request from the parent terminal device 10 sets the terminal device 20 (4) as a communication destination, and when the setting is completed, a route change completion report is sent to the parent terminal device 10. Sending (S512), the parent terminal device 10 sends its end report to the center device 30 (S513). The center device 30 that has received the report from the parent terminal device 10 updates the electric field strength, the charging current amount, and the subordinate device (terminal device) information of the terminal information 20 (8) provided therein (S514), and performs processing. Exit.

  In the above processing, the terminal device 20 (3) is connected to the terminal devices 20 (6) and 20 (7) in addition to 20 (8) at the lower level of the latest hierarchy. The same processing can be performed for 6) and 20 (7). In that case, for example, priorities are set between the terminal devices 20 (6) to 20 (8), the terminal device 20 (8) is first changed, and the predicted power consumption and the solar cell power generation in that case are compared. If the predicted power consumption exceeds the solar battery power generation amount, the connection path of the terminal device 20 (7) is then changed, the same comparison is performed, and the connection path change with the terminal device 20 (6) is further changed. For example, the connection path changing process may be performed sequentially.

  In addition, in the illustrated example, since the terminal device 20 (5) is also in the uppermost hierarchy, the terminal device 20 (5) is also targeted for selection of the terminal device in the uppermost hierarchy. Can be. Therefore, the selection order of the terminal device that is the connection destination in the uppermost hierarchy when changing the connection route is, for example, the electric field strength acquired by the communication operation when performing the edge registration in the monitoring system including the parent device and the child device. In comparison, based on the result, a higher priority than the terminal device 20 (5) is set for the terminal device 20 (4) as a new connection destination candidate of the terminal device 20 (8). Yes. In this case, if the terminal device 20 (4) is also in a state where the power generation amount of the solar cell does not exceed the expected power consumption, the terminal device 20 (5) is selected.

  Further, when the connection route is changed, the connection partner information is rewritten in a storage means (not shown) of each terminal device, and the parent terminal device 10 or further the center device 30 is notified and stored in each. Rewrite route information.

  According to the above embodiment, when each terminal device 20 compares the power generation amount of the solar battery of its own terminal device with its predicted power consumption, it is predicted that the power generation amount of its own terminal device will be insufficient. By changing the connection route, the amount of communication that passes through the terminal itself can be reduced in advance, and the necessary communication can be performed without requiring extra stored power or increasing the capacity of the solar cell as in the past. Can do.

  In the above description, a solar cell has been described as an example of a power source. However, the present invention is not necessarily limited thereto, and the communication system according to the present invention uses a power source that uses other natural energy such as wind power and wave power. It is also applicable to cases.

In the above description, when the connection path is changed, the terminal apparatus (slave device) that issues the connection path change request notifies the center apparatus 30 of a predetermined terminal apparatus as a change destination candidate. The connection destination terminal device (slave unit) may be selected based on the connection route registered on the side, the charging current amount data, the communication electric field strength, and the subordinate unit information.
In that case, an optimal terminal device is selected from a plurality of candidate terminal devices with reference to the route change determination level f (x) and the subordinate device information reference table.

As described above, in the present embodiment, it is possible to secure stable power using a solar cell, detect the charging capacity of the solar cell, and specify power consumption for each terminal device and identification between terminal devices. The electric field strength information of the low power radio can be managed by the center device.
Therefore, it is possible to set a route (route) based on the electric field strength and the solar charge amount level, avoid concentration of access to the specific terminal device, and set an optimum route.

It is a block diagram of the terminal device used for the communication system which concerns on this Embodiment. It is the block diagram which showed roughly the remote monitoring system which concerns on one Embodiment of the communication system of this invention which used the said terminal device for the subunit | mobile_unit. It is the list which contrasted and showed the content determined from the indexed path change judgment level and the above-mentioned subordinate child machine information reference table T3. It is a flowchart explaining the procedure which transmits electric field strength information from a terminal device to a center apparatus. It is a flowchart explaining the procedure which transmits charge current amount from a terminal device to a center apparatus. It is a path | route change flowchart which concerns on embodiment of this invention for performing a path | route change. It is the block diagram which showed roughly the remote management system using a solar cell as a drive power supply of the conventional subunit | mobile_units, such as for communication.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Master unit (parent terminal device), 20 ... Slave unit (terminal device), 21 ... Main control unit, 22 ... Radio unit, 23 ... I / O interface, 25 ... Charge control and charge amount measurement unit, 26... Rechargeable battery or capacitor, 28... Electric field strength measurement unit, 40.

Claims (5)

A terminal device used in a communication system configured by a terminal device in which a center device and a plurality of terminal devices are connected in multiple stages,
A power generation device using natural energy; means for calculating a charge amount of the power generation device; means for detecting communication electric field strength of the terminal device; and means for transmitting the charge amount information and communication electric field strength data to a center device. And a means for transmitting a signal for urging the terminal device to change the route when the charging power amount is equal to or less than a predetermined value. The terminal device according to claim 1,
A means for transmitting a connection route change request to the center device when a signal prompting a route change is received from another terminal device, and a connection route change is made to the connection route when a connection route change instruction is received from the center device A terminal device comprising means. The terminal device according to claim 2, wherein the means for transmitting a connection path change request transmits terminal device information as a connection partner candidate based on the electric field strength information to a center device. A center device used in a communication system configured by a terminal device in which a center device and a plurality of terminal devices are connected in multiple stages,
Storage means for storing the charging power amount of each terminal device, electric field strength data, and subordinate terminal device data transmitted from each terminal device,
Means for determining whether or not to change the change destination terminal device included in the connection route change request based on the electric field strength data, the charging power amount and the lower connection terminal device data when receiving the connection route change request from the terminal device; Have
When it is determined that the change is possible, the center device instructs the terminal device to change the connection route to the designated connection route change destination terminal device.   A communication system comprising the terminal device according to claim 1 and the center device according to claim 4.

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