JP4645939B2 - Mobile base station position determination system, terminal position determination system, mobile base station, radio terminal and base station position determination program - Google Patents

Description

  The present invention relates to a mobile base station location determination system in a multi-hop wireless network, and in particular, selects a mobile station that directly communicates with a mobile base station from a battery power remaining amount information, location information, and the like of a plurality of mobile stations. The present invention relates to a mobile base station position determination system, a terminal position determination system, a mobile base station, a wireless terminal, and a base station position determination program for determining an optimal position of a base station.

  A multi-hop wireless network enables direct communication between a plurality of wireless terminals located in close proximity to each other without going through a base station, and allows two wireless terminals to communicate by relaying other terminals. The communication is performed by forming a wireless network independent of the public communication network between a plurality of terminals.

  In a multi-hop wireless network, unlike in the case of a public communication network that performs only data communication between a wireless terminal and a base station, data is relayed between the base station and all the wireless terminals under its control. The terminal needs to do. When the base station communicates with the wireless terminal via a plurality of wireless terminals interposed between the base station and the wireless terminal, any communication relays the wireless terminal that directly communicates with the base station.

  In such a case, the power consumed by a wireless terminal with a smaller number of hops from the base station increases. For this reason, there is a possibility that the battery of the wireless terminal that communicates directly with the base station is consumed intensively, the battery of the relay wireless terminal runs out, and communication becomes impossible.

  In order to solve such a problem, it is necessary to determine a wireless terminal that performs direct communication with the base station in consideration of the remaining battery power of the wireless terminal. Furthermore, it is necessary to determine the position of the mobile base station that directly communicates with the wireless terminal.

  An example of a method similar to the solution of such a problem is described in, for example, Japanese Unexamined Patent Application Publication No. 2002-290345 (Patent Document 1) and Japanese Unexamined Patent Application Publication No. 2003-124874 (Patent Document 2).

  The method of Patent Document 1 determines a base station position of a wireless local communication network (wireless LAN). In the method of Patent Document 1, a mobile terminal is placed at a desired position within the movement range, and a wireless component for checking a reception level is placed at a candidate position of the wireless base station. In such a state, a signal is transmitted from the mobile terminal, the presence / absence of a response signal from the wireless component for that signal, and the reception level when there is a response signal are monitored, and the candidate position is set as the candidate position of the radio base station. It is to decide whether it is appropriate.

The method of Patent Document 2 provides a power saving method for a wireless terminal. In this method, when the battery power of the wireless terminal is low, the resynchronization establishment cycle is lengthened to save power, while when the battery power is high, the resynchronization establishment cycle is returned to the normal state. The power is not saved. According to the method of Patent Document 2, the degree of power saving can be adjusted according to the remaining battery power.
JP 2002-290345 A JP 2003-124874 A

  All of the conventional techniques described above have the following problems.

  In the method of Patent Document 1, a wireless terminal is placed at a desired position within its movement range, a wireless component is placed at a candidate position of a wireless LAN base station, a signal is transmitted from the wireless terminal, and the wireless component corresponding to the signal is transmitted. The presence / absence of a response signal from the receiver and the reception level when there is a response signal are monitored to determine whether the candidate position is appropriate as a candidate position of the wireless LAN base station.

  According to the method disclosed in Patent Document 1, it is possible to determine the position of a base station suitable for a wireless terminal. However, the criterion for the determination is merely the reception strength, and does not take into consideration the remaining amount of battery power expected to be a problem in the multi-hop wireless network.

  Furthermore, this method is applicable to a wireless LAN that performs communication between a terminal and a base station, and is not intended for use in a multi-hop wireless network that relays a wireless terminal and communicates between wireless terminals. Absent.

  In the method of Patent Document 2, a power saving method for a wireless terminal is provided, and the degree of power saving can be adjusted according to the remaining battery power.

  However, the method of Patent Document 2 is a method for saving power of a wireless terminal, and does not provide remaining battery power remaining information that is important in a multi-hop wireless network from a wireless terminal to a base station.

  An object of the present invention is to solve the above-mentioned drawbacks of the prior art, and in a multi-hop wireless network, a mobile base station capable of avoiding communication instability due to insufficient battery power remaining in a wireless terminal that relays communication between the base station and the wireless terminal The object is to realize a position determination system, a terminal position determination system, a mobile base station, a radio terminal, and a base station position determination program.

A first mobile base station location determination system according to the present invention includes a plurality of wireless terminals and a mobile base station, and the wireless terminal relays data communication between the mobile base station and the wireless terminal. A mobile base station position determination system for determining a position of a mobile base station, wherein the mobile base station has battery remaining power information and position information of each of a plurality of wireless terminals at each of a plurality of candidate locations of its own position. The current balance information indicating the value obtained by subtracting the current consumption from the charging current, and the reception intensity information obtained from the wireless signal transmitted from each wireless terminal are acquired, and the mobile base station and the relay are relayed based on the acquired information. Select one or more first-stage wireless terminal candidates from wireless terminals that perform direct communication, and select the first-stage wireless terminal candidates selected at each of the plurality of candidate locations. DOO in, determines the position for installing the mobile base station from the candidate site, if the candidate site for installing the mobile base station is a plurality of the plurality of candidate sites, many battery power remaining amount of the first stage wireless terminal, A candidate site with a large number of first-stage wireless terminals is selected .

A first terminal location determination system according to the present invention includes a wireless terminal having a mobile base station function and a plurality of wireless terminals, and the wireless terminal performs data communication between the wireless terminal having a mobile base station function and the wireless terminal. A terminal location determination system for determining a location of a wireless terminal having a function of a mobile base station in a multi-hop wireless network of a relaying method, wherein the wireless terminal having the function of a mobile base station In each of the plurality of candidate sites, the battery power remaining amount information, the position information, the current balance information indicating the value obtained by subtracting the consumption current from the charging current, and the wireless signal transmitted from each wireless terminal are obtained. A wireless terminal that obtains reception strength information and performs direct communication with a wireless terminal having a mobile base station function based on the acquired information without relaying. Select one or more first-stage wireless terminal candidates from among the candidates, and select a position to install a wireless terminal having a mobile base station function based on the first-stage wireless terminal candidates selected at each of the plurality of candidate locations. If there are multiple candidate sites that are determined from the ground and where wireless terminals having mobile base station functions are installed, the battery power remaining in the first-stage wireless terminal is large and the number of first-stage wireless terminals among the plurality of candidate sites Select candidate sites with more

A second mobile base station position determination system according to the present invention includes a computer having a mobile base station function and a plurality of wireless terminals, and the wireless terminal relays data communication between the mobile base station and the wireless terminal. A mobile base station position determination system for determining a position of a mobile base station in a multi-hop wireless network, wherein a computer is configured to store battery power of each of a plurality of wireless terminals at each of a plurality of candidate locations of the position of the mobile base station. Remaining amount information, position information, current balance information indicating a value obtained by subtracting current consumption from charging current, and reception intensity information obtained from a wireless signal transmitted from each wireless terminal, based on the acquired information, Select one or more first-stage wireless terminal candidates from wireless terminals that communicate directly with the mobile base station without relay, and select multiple candidate locations. Based on the candidate of the selected first-stage wireless terminals les, it determines the position for installing the mobile base station from the candidate site, if the candidate site for installing the mobile base station is a plurality of the plurality of candidate areas A candidate site with a large amount of battery power remaining in the first stage wireless terminal and a large number of first stage wireless terminals is selected .

A first mobile base station of the present invention is a mobile base station in a multi-hop wireless network that performs data communication by relaying a wireless terminal with a plurality of wireless terminals under its control. In each of the plurality of candidate sites, the battery power remaining amount information, the position information, the current balance information indicating the value obtained by subtracting the consumption current from the charging current, and the wireless signal transmitted from each wireless terminal are obtained. Received strength information is acquired, and based on the acquired information, one or more first-stage wireless terminal candidates are selected from wireless terminals that perform direct communication without relaying by wireless terminals, and each of the plurality of candidate locations based on the candidate of the selected first-stage wireless terminal to determine the location of the mounting from the candidate site, if the candidate site for installation there are multiple, among the plurality of candidate sites, the first stage wireless terminal server Teripawa remaining amount is large, and the number of the first-stage wireless terminal selects more candidate sites.

A first wireless terminal according to the present invention is a wireless terminal having a function of a mobile base station in a multi-hop wireless network that performs data communication by relaying a wireless terminal with a plurality of wireless terminals under its control. In each of the plurality of candidate locations of the own position, the remaining battery power information of each of the plurality of wireless terminals, the position information, the current balance information indicating the value obtained by subtracting the consumption current from the charging current, and transmitted from each wireless terminal Receiving strength information obtained from a wireless signal, selecting one or more first-stage wireless terminal candidates from wireless terminals that perform direct communication without relaying by the wireless terminal based on the acquired information, based on the candidate of the selected first-stage wireless terminals candidate site respectively, to determine the location of the mounting from the candidate site, if the candidate site for installation are a plurality, the plurality of candidate sites In the middle, the battery power remaining amount of the first-stage wireless terminal are many, select the number of the first-stage wireless terminal is often a candidate site.

A second wireless terminal of the present invention is a wireless terminal in a multi-hop wireless network that performs data communication of a method of relaying a wireless terminal with a connected mobile base station,
When receiving a radio signal for detecting a wireless terminal capable of communication from the mobile base station,
A wireless terminal that transmits battery power remaining amount information, position information, and current balance information indicating a value obtained by subtracting current consumption from a charging current to the mobile base station .

The first mobile base station location determination program of the present invention is executed on a mobile base station in a multi-hop wireless network that performs data communication of a method of relaying wireless terminals with a plurality of wireless terminals under its control. A base station position determination program for determining the position of a mobile base station, wherein the mobile base station has battery remaining power information, position information, and charging for each of a plurality of wireless terminals in each of a plurality of candidate locations of its own position. Current balance information indicating a value obtained by subtracting current consumption from current and reception intensity information obtained from a radio signal transmitted from each wireless terminal are acquired, and based on the acquired information, the relay is directly performed without relaying by the wireless terminal. A function for selecting one or more first-stage wireless terminal candidates from wireless terminals performing communication, and a first-stage wireless terminal selected at each of one or more candidate locations The candidate based on a function of determining the location of the mounting from the candidate site, if the candidate site for installing the mobile base station is a plurality of the plurality of candidate sites, battery power remaining amount of the first stage wireless terminal A function of selecting candidate sites with a large number of first stage wireless terminals is executed.

  According to the mobile base station position determination system, terminal position determination system, mobile base station, radio terminal, and base station position determination program of the present invention, the following effects are achieved.

  Based on the remaining battery power information, position information, and received intensity information of each wireless terminal, the mobile base station selects the first stage wireless terminal that communicates directly with the mobile base station, and based on the position of the selected first stage wireless terminal. In order to determine the position of the mobile base station, it is possible to avoid communication instability due to insufficient battery power remaining in the wireless terminal that relays communication between the base station and the wireless terminal, and to realize stable multi-hop wireless communication it can.

  Preferred embodiments of the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of a mobile base station position determination system according to the present embodiment.

  Referring to FIG. 1, the mobile base station position determination system is configured by a mobile base station 10 and a plurality of radio terminals 20, 30, 40, 50.

  The mobile base station 10 can move in areas that can be entered, excluding areas such as restricted areas and private land.

  Moreover, although the radio | wireless terminals 20, 30, 40, and 50 can move, they do not need to move.

  In FIG. 1, the dotted line between the mobile base station 10 and the wireless terminal 20, the dotted line connecting the wireless terminals 20, 30, and 40, and the dotted line connecting the wireless terminal 20 and the wireless terminal 50 are connected wirelessly. Represents that. Moreover, the solid line connecting between the wireless terminals 20, 30, 40, 50 and the respective sensors 20a, 30a, 40a, 50a and the respective control devices 20b, 30b, 40b, 50b represents a wired connection. . Here, the sensors 20a, 30a, 40a, 50a and the control devices 20b, 30b, 40b, 50b will be described in the description of the reception operation of the mobile base station 10 in FIG.

  The mobile base station 10 and the respective sensors 20a, 30a, 40a, 50a or the respective control devices 20b, 30b, 40b, 50b according to the present embodiment perform data communication via the radio terminals 20, 30, 40, 50, respectively. Can do. These data communications are performed after the multi-hop communication path is established.

  The configurations of the mobile base station 10 and the radio terminals 20, 30, 40, 50 will be described with reference to FIGS. 3 and 5, respectively.

  Communication between the mobile base station 10 and the radio terminals 20, 30, 40, 50 is performed by a route indicated by a dotted line. For example, when the wireless terminal 50 transfers data to the mobile base station 10, the data is transferred via the wireless terminal 20. For example, when the wireless terminal 40 transfers data to the mobile base station 10, the data is transferred via the wireless terminal 30 and the wireless terminal 20.

  For this reason, in a wireless terminal that relays transfer, power consumed for communication increases. In particular, in the wireless terminal 20 that directly communicates with the mobile base station 10, the frequency of data transfer is higher than that of other wireless terminals, and the power consumed for communication is significantly increased.

  FIG. 2 is a diagram illustrating an example of the configuration of a multi-hop route according to the present embodiment. In a multi-hop wireless network, a mobile terminal station 10 includes a plurality of wireless terminals, and the wireless terminal relays data communication between the mobile base station 10 and the wireless terminal.

  Referring to FIG. 2, a multi-hop communication path (hereinafter abbreviated as a multi-hop path) in which wireless terminals are connected in a tree structure is configured with the mobile base station 10 as a route. In the present invention, it is assumed that the mobile base station 10 and the wireless terminal are configured by a tree-shaped multihop path. That is, the position of the mobile base station 10 is determined according to the present invention, and after moving the mobile base station 10 to the determined position, a tree-shaped multihop path is constructed.

  In order to construct a multi-hop route, the mobile base station 10 needs to first select the first-stage wireless terminals 60 and 70 that directly communicate with the mobile base station 10 from the wireless terminals. The first-stage wireless terminals 60 and 70 relay the transfer to all the wireless terminals connected to them. For this reason, it is preferable that these terminals have a large amount of remaining battery power.

  On the other hand, when the number of first-stage wireless terminals is large and communication can be distributed, the remaining battery power of the first-stage wireless terminals may not be large.

  The mobile base station 10 is preferably externally powered such as an AC (alternating current) power supply, but is internally powered such as a solar cell, primary battery, secondary battery, fuel cell, or capacitive element, or externally powered and internally powered. A combination may be used. Moreover, although the wireless terminals 20, 30, 40, and 50 are assumed to be internally fed, they may be externally fed or a combination of externally powered and internally fed.

  The present invention provides a system for searching for the optimal first-stage radio terminals 60 and 70 and determining the optimal position of the mobile base station 10.

  FIG. 3 is a block diagram showing the configuration of the mobile base station 10 according to the present embodiment. In addition, the main part of FIG. 1 is referred as needed.

  Referring to FIG. 3, the mobile base station 10 includes an antenna 11, a transmission / reception selector switch 12, a radio reception unit 13, a demodulation unit 14, a data processing unit 15, a modulation unit 16, a radio transmission unit 17, a reception intensity measurement unit 18, and a database 19. Consists of.

  First, the reception operation of the mobile base station 10 will be described.

  In the mobile base station 10, when receiving data, the transmission / reception selector switch 12 is connected to the reception side, and the signal received from the antenna 11 is transmitted to the radio reception unit 13. When the wireless signal is received by the wireless receiver 13, the demodulator 14 can demodulate the wireless signal and transmit a frame (data surrounded by a flag signal) to the data processor 15. The data transmission may be in a form other than the frame.

  The reception intensity measuring unit 18 measures the reception intensity obtained from the radio signal received from the radio reception unit 13 and transmits the value to the data processing unit 15.

  The data processing unit 15 determines whether the received frame is addressed to the mobile base station 10, and when the frame is other than the mobile base station 10, to the modulation unit 16 to transfer to the radio terminals 20, 30, 40, 50. Pass the frame. If the received frame is addressed to the mobile base station 10, the data included in the frame can be analyzed and the data can be stored in the database 19.

  Next, data included in the received frame will be described.

  There are two types of data received by the mobile base station 10: data received from the radio terminals 20, 30, 40, 50 and data received from the sensors 20a, 30a, 40a, 50a or the control devices 20b, 30b, 40b, 50b. It is divided into.

  The data received by the mobile base station 10 from the radio terminals 20, 30, 40, 50 includes the remaining battery power information, current balance information, and position information received from each radio terminal when each radio terminal is searched. (Latitude, longitude) are included. Here, the current balance information indicates a value obtained by subtracting the average consumption current from the average charging current in each wireless terminal. These data are received before the multi-hop route is established or changed.

  For determining the position of the mobile base station, remaining battery power information, current balance information, position information (latitude, longitude), and reception intensity information are used.

  The data received by the mobile base station 10 from the radio terminals 20, 30, 40, 50 includes a control signal for constructing a multi-hop route. The data received by the mobile base station 10 from the radio terminals 20, 30, 40, 50 includes communication data from the sensors 20a, 30a, 40a, 50a or the control devices 20b, 30b, 40b, 50b. These communication data are received after the multi-hop route is established.

  As an example of communication data, when the sensors 20 a, 30 a, 40 a, 50 are temperature sensors, humidity sensors, etc., environmental data such as temperature, humidity, etc. are transmitted to the mobile base station 10. These data are further transmitted via the mobile base station 10 to the center managing the area.

  The control devices 20b, 30b, 40b, and 50b are, for example, terminals that remotely control gas, water taps, and electric breakers, and are used by regional centers to manage facilities such as public facilities. Is.

  The data received by the data processing unit 15 has been described above. However, the control signal and the mobile base station 10 and the sensors 20a, 30a, 40a, 50a or the control devices 20b, 30b, 40b, The communication data between 50b is used after the determination of the position of the mobile base station 10 and the movement of the mobile base station 10 to the position, and is not used for determining the position of the mobile base station that is the subject of the present invention. Absent.

  Here, the position determination of the mobile base station 10 and the multi-hop path construction realized thereafter, the communication between the mobile base station 10 and the sensors 20a, 30a, 40a, 50a or the control devices 20b, 30b, 40b, 50b In order to show the relationship, the control signal and the mobile base station 10 for constructing these multi-hop paths and the communication data of the sensors 20a, 30a, 40a, 50a or the control devices 20b, 30b, 40b, 50b are also described. .

  Next, the transmission operation of the mobile base station 10 will be described.

  The data processing unit 15 transmits a frame to the modulation unit 16 when detecting the wireless terminals 20, 30, 40, 50, constructing a multi-hop route, or performing data communication. Detection of the radio terminals 20, 30, 40, 50 by the mobile base station 10 needs to be performed in order to construct a multi-hop route.

  In addition, after the multi-hop path is established between the mobile base station 10 and the radio terminals 20, 30, 40, 50, the mobile base station is connected to the radio terminals 20, 30, 40, 50 by the sensors 20a, 30a. , 40a, 50a or each of the control devices 20b, 30b, 40b, 50b.

  The modulation unit 16 modulates the frame received from the data processing unit 15 and transmits a radio signal to the radio transmission unit 17. At the time of data transmission, the transmission / reception selector switch 12 is connected to the transmission side, and the wireless signal transmitted from the wireless transmission unit 17 is transmitted from the antenna 11.

  The database 19 of the mobile base station 10 stores information necessary for constructing a multi-hop route such as selection of the first stage wireless terminal and position determination of the mobile base station. In addition, map information necessary for determining the position of the mobile base station is also stored.

  When the position of the mobile base station 10 is determined and a multi-hop route is constructed, the link information obtained by construction of the multi-hop route and the sensors 20a, 30a, 40a, 50a or the control devices 20b, 30b are stored in the database 19. , 40b and 50b are stored.

  FIG. 4 is a diagram illustrating an example of information for selecting the first stage wireless terminal according to the present embodiment.

  Referring to FIG. 4, information for selecting a first-stage wireless terminal includes a wireless terminal number for identifying each wireless terminal, a remaining battery power, a power balance, a communication duration, a latitude, a longitude indicating the position of the wireless terminal, and a wireless signal Reception strength of.

  Note that the communication duration is the value obtained by dividing the remaining battery power of each wireless terminal by the current balance. Since the energy does not run out when the power balance is positive, the communication duration is set to infinity (∞). Store.

  FIG. 5 is a diagram illustrating a configuration of the wireless terminal 20 according to the present embodiment. The following description is given for the case of the wireless terminal 20, but the same applies to the wireless terminals 30, 40, and 50.

  First, the reception operation of the wireless terminal 20 will be described. In addition, the main part of FIG. 1 is referred as needed.

  Referring to FIG. 5, when the wireless terminal 20 receives data from the mobile base station 10 or the wireless terminals 30, 40, 50, the transmission / reception changeover switch 22 is connected to the receiving side, and the signal received by the antenna 21 is wireless It is transmitted to the receiving unit 23.

  The data received by the wireless terminals 20, 30, 40, 50 includes a signal for detecting the wireless terminal, a control signal for constructing a multi-hop route, the sensors 20a, 30a, 40a, 50a or the control devices 20b, 30b. , 40b, 50b.

  Next, the demodulator 24 demodulates the signal and transmits data to the data processor 25.

  The reception intensity measuring unit 28 measures the reception intensity of the radio signal received from the radio reception unit 23 and provides the value to the data processing unit 25. The data processing unit 25 acquires reception intensity information of radio signals received from the mobile base station 10 or the radio terminals 30, 40 and 50.

  In addition, the data processing unit 25 determines whether the received frame is addressed to the radio terminal 20, and when the frame is not addressed to the radio terminal 20, to transfer to the mobile base station 10 or the radio terminals 30, 40, 50, The frame is passed to the modulation unit 26.

  If the frame is addressed to the wireless terminal 20, the data included in the frame is analyzed, and if necessary, the data is transmitted to the subsequent sensor 20a or the control device 20b.

  The data processing unit 25 can acquire position information including the latitude and longitude of the wireless terminal 20 using GPS (Global Positioning System) or the like.

  The data processing unit 25 acquires the remaining battery power and the average charging current and average discharging current values for a certain period from the remaining battery monitoring unit 29, and calculates a current balance that is a value obtained by subtracting the average discharging current from the average charging current. Can be calculated. Furthermore, position information, remaining battery power information, and current balance information can be transmitted to the mobile base station 10.

  If the wireless terminal 20 does not move, the position information including the latitude and longitude can be registered by temporarily connecting the GPS to the wireless terminal 20 when the wireless terminal 20 is newly installed. In such a case, it is not necessary to continuously provide the GPS function in the wireless terminal 20.

  On the other hand, when the wireless terminal 20 moves, the wireless terminal 20 may be provided with a GPS function so that the position information can be always read.

  Next, data transmission from the wireless terminal 20 will be described.

  The data processing unit 25 includes data such as remaining battery power, information on current balance and latitude, and position information including latitude and longitude, which are transmission information when a wireless terminal is detected, and control information and sensors 20a for constructing a multi-hop route. , 30a, 40a, 50a or data received from the control devices 20b, 30b, 40b, 50b can be transmitted to the mobile base station 10 in the form of a frame.

  These data are modulated by the modulation unit 26 and transmitted to the wireless transmission unit 27. At the time of data transmission, the transmission / reception selector switch 22 is connected to the transmission side, and the signal transmitted from the wireless transmission unit 23 is transmitted from the antenna 21.

  Note that when the radio terminal 20 receives a radio signal from the mobile base station or another radio terminal, the reception strength at that time exceeds a certain threshold value, and when the signal strength is sufficient, a response is returned. Is less than the threshold value and the signal strength is insufficient, no response is returned.

  The mobile base station location determination system according to the present invention described above includes a plurality of radio terminals 20, 30, 40, and 50 and the mobile base station 10, and the radio terminals 20, 30, 40, and 50 are connected to the mobile base station and the mobile base station. In a multi-hop wireless network that relays data communication between wireless terminals, reception is obtained from the remaining battery power information of each of the wireless terminals 20, 30, 40, and 50, position information, and wireless signals transmitted from the respective wireless terminals. Based on the strength information, the first stage wireless terminal that communicates directly with the mobile base station 10 is selected, and then the position where the mobile base station 10 is installed is determined based on the position information of the first stage wireless terminal.

  Next, the operation according to the present embodiment will be described in detail with reference to the drawings.

  FIG. 6 is a flowchart for explaining processing for searching for a first-stage wireless terminal according to the present embodiment. In addition, the main part of FIG. 1, FIG. 3 is referred as needed.

  Referring to FIG. 6, first, the data processing unit 15 installed in the mobile base station 10 transmits a radio signal to all the radio terminals in order to detect a communicable radio terminal (step 601). .

  The transmission of the radio signal may be broadcast. Further, if necessary, a radio signal is transmitted after an address is assigned to each radio terminal.

When the reception intensity of the received wireless signal exceeds a certain threshold, the wireless terminal that has received the wireless signal from the mobile base station 10 has position information including battery remaining power information, current balance information, latitude, and longitude. To the mobile base station 10, and the reception intensity measurement unit 18 measures the reception intensity from the received radio signal (step 602).

  The data processing unit 15 registers the received data in the database 19 for each of the wireless terminals 20, 30, 40, and 50, and calculates the communication duration from the remaining battery power and the current balance (step 603).

  Then, as long as there are other wireless terminals that can communicate, the above operation is repeated (step 604).

  Among wireless terminals capable of communication, wireless terminals whose communication duration is long and the reception intensity of wireless signals from the wireless terminals is larger than a certain threshold are determined as candidates for the first stage wireless terminal (step 605).

  Note that the number of first-stage wireless terminals is not limited to one and may be plural.

  Next, selection of candidates for the first stage wireless terminal will be described based on the data in FIG.

  Here, it is assumed that wireless terminal number 3 is not registered in the database because communication with mobile base station 10 is impossible, and the threshold value of reception strength is set to -85 dBm. The wireless terminal numbers of wireless terminals that can communicate with the mobile base station 10 are 1, 2, 4, and 5, excluding the wireless terminal 6 whose reception intensity is less than the threshold. When a wireless terminal having a long communication duration is selected from these wireless terminals, the wireless terminal with number 1 indicating that the communication duration is infinite becomes a candidate for the first stage wireless terminal. Alternatively, the communication duration threshold may be set to 300, and the wireless terminals with numbers 1, 2, and 4 may be candidates for the first stage wireless terminal.

  In this way, each time the mobile base station 10 is moved to change the position, the first stage wireless terminal candidate is searched for by the above processing.

  FIG. 7 is a flowchart for explaining processing for determining the position of the mobile base station 10 according to the present embodiment.

  Referring to FIG. 7, first, the mobile base station 10 is moved to perform a process (shown in FIG. 6) for searching for candidates for the first stage wireless terminal at a certain point (step 701).

  The process of searching for candidates for the first stage radio terminal is performed as long as there are other candidate locations for the mobile base station (step 702).

  Next, a mobile base station candidate site is selected that has a large amount of battery power remaining in the first stage wireless terminal and a large number of first stage wireless terminals (step 703).

  Then, based on the position information and map information including the latitude and longitude of the first-stage wireless terminal in the database 19, an area where the mobile base station 10 can enter and can communicate with the first-stage wireless terminal is extracted (step S1). 704).

  FIG. 8 is a diagram illustrating an example of determining a position where the mobile base station 10 according to the present embodiment is installed.

  Referring to FIG. 8, first, an area where wireless communication is possible with the first-stage wireless terminals 60 and 70 as the center is extracted as indicated by a dotted line in the figure. The area within the dotted line in which wireless communication is possible is extracted based on the reception intensity of the radio wave transmitted from the first-stage wireless terminals 60 and 70, but may be extracted based on the distance from the first-stage wireless terminals 60 and 70.

  Next, an area in which the mobile base station 10 can communicate from the two first-stage radio terminals 60 and 70 and the mobile base station 10 can enter is extracted, and the area shown in black in the extracted drawing is the area of the mobile base station 10. The area where communication is possible. It should be noted that the installation location of the mobile base station 10 in the area can be freely selected.

  Next, the mobile base station 10 moves to an optimal position. After the movement, a multi-hop route is constructed between the mobile base station 10 and the wireless terminal. After the construction, the mobile base station 10 and the sensors 20a, 30a, 40a, 50a or the control devices 20b, 30b, 40b, 50b are constructed. Data communication is performed between the two.

  Thus, in the mobile base station position determination system of the present invention, the position of the mobile base station 10 is determined based on the position information of the first stage radio terminals 60 and 70 and the accessible area information of the mobile base station 10.

  In the above embodiment, a multi-hop route having a tree structure has been described as an example of the configuration of the multi-hop route. However, the present invention is not limited to this, and even in a mesh structure or other communication network structure, it is exactly the same. The first stage radio terminal can be determined and the position of the mobile base station 10 can be determined.

  In the above embodiment, the mobile base station 10 and the wireless terminal constitute a multi-hop route. Instead of the mobile base station 10, the wireless terminal 110 having the function of the mobile base station 10 is used to A route can also be configured.

  FIG. 9 is a diagram illustrating a configuration of a terminal location determination system according to the present embodiment. The wireless terminal 110 needs to add a database to the configuration of the wireless terminals 20, 30, 40, and 50 shown in FIG. 5 (not shown).

  On the other hand, the configuration of the wireless terminals 20, 30, 40, 50 may be as shown in FIG.

  The position of the wireless terminal 110 can be determined in the same manner as in the case of the mobile base station 10 described above.

  According to the embodiment described above, the first-stage radio terminals 60 and 70 that perform direct communication with the mobile base station 10 based on the battery power remaining amount information, the position information, and the reception intensity information of the respective radio terminals. In order to determine the position of the mobile base station 10 based on the position of the selected first-stage radio terminals 60 and 70 selected, the remaining battery power of the radio terminal that relays communication between the mobile base station 10 and the radio terminal Communication instability due to shortage can be avoided, and stable multi-hop wireless communication can be realized.

  Next, a second embodiment of the present invention will be described with reference to the drawings.

  In the first embodiment, the first-stage wireless terminal having a large remaining battery power and a reception strength greater than a certain threshold value is selected. However, when no other wireless terminal is connected under the first-stage wireless terminal, the remaining battery power A few wireless terminals can be used as the first stage wireless terminals.

  FIG. 10 is a flowchart for explaining processing for searching for a first-stage wireless terminal according to the present embodiment.

  Referring to FIG. 10, first, the mobile base station 10 transmits a radio signal to all the radio terminals in order to detect a communicable radio terminal (step 1001).

When the reception intensity of the received wireless signal exceeds a certain threshold, the wireless terminal that has received the wireless signal from the mobile base station 10 has position information including battery remaining power information, current balance information, latitude, and longitude. To the mobile base station 10, and the mobile base station 10 measures the received intensity from the received radio signal (step 1002).

  The mobile base station 10 registers the received data in the database 19 for each wireless terminal, and calculates the communication duration from the remaining battery power and the current balance (step 1003).

  The above operation is repeated as long as there are other wireless terminals that can communicate (step 1004).

  Next, out of communicable wireless terminals, wireless terminals whose communication duration is long and the reception strength of the wireless signal from the wireless terminal is larger than a certain threshold are set as candidates for the first stage wireless terminal.

  In addition, in order to operate a wireless terminal with a low remaining battery power for as long as possible, a wireless terminal having a wireless signal reception strength greater than a certain threshold and a short communication duration is subordinate to the wireless terminal. As a first-stage wireless terminal candidate on the condition that is not connected (step 1005). However, after the first-stage wireless terminal is determined, it is necessary to construct a multi-hop route so as not to connect the wireless terminal under it.

  Note that the number of first-stage wireless terminals is not limited to one and may be plural.

  FIG. 11 is a diagram illustrating an example of a multi-hop route including a first-stage wireless terminal 90 that does not connect wireless terminals under the control of this embodiment.

  The first-stage wireless terminal 80 needs to be a wireless terminal with a large remaining battery power in order to connect a wireless terminal under its control, but the first-stage wireless terminal 90 does not connect a wireless terminal under its control, so The number of wireless terminals may be small.

  In this way, by not connecting other wireless terminals under the first-stage wireless terminal 90 with a small remaining battery power level, it is possible to suppress the power consumption of the wireless terminal with a small remaining battery power level as much as possible.

  The mobile base station 10 of the present invention not only realizes its operation in hardware, but also includes a mobile base station location determination program (application) 100 that executes each of the functions described above as a computer constituting the mobile base station 10. It can be realized by software by being executed by the data processing unit 15 which is a processing device. The mobile base station position determination program 100 is stored in a magnetic disk, a semiconductor memory, or other recording medium, loaded from the recording medium to the data processing unit 15, and controls the operation thereof, thereby realizing each function described above. .

  In the above embodiment, the mobile base station 10 detects a wireless terminal, determines an appropriate first-stage wireless terminal candidate, then determines the position of the mobile base station 10, and constructs a multi-hop route. , By collecting data at multiple locations by using a notebook computer (with built-in wireless communication card and capable of wireless communication) with the mobile base station function described above, determine the optimal location, It is also possible to install a mobile base station or a non-moving base station at that location.

  When using the notebook personal computer, the mobile base station position determination program (application) 100 can be loaded onto the notebook personal computer to realize the function of the mobile base station. Further, the mobile base station position determination program can realize the function of the mobile base station by incorporating it in advance in a mounted wireless communication card in addition to the magnetic disk.

  In addition, the mobile base station may be a mobile base station by carrying a base station that is not originally moved by an operator or by mounting it on a moving means such as an automobile.

  The present invention has been described above with reference to a plurality of preferred embodiments. However, the present invention is not necessarily limited to the above embodiments, and various modifications can be made within the scope of the technical idea. .

It is a block diagram which shows the structure of the mobile base station position determination system by the 1st Example of this invention. It is a figure which shows an example of a structure of the multihop path | route by 1st Example of this invention. It is a block diagram which shows the structure of the mobile base station by the 1st Example of this invention. It is a figure which shows an example of the information for selecting the first rank radio | wireless terminal by 1st Example of this invention. It is a figure which shows the structure of the radio | wireless terminal by 1st Example of this invention. It is a flowchart for demonstrating the process which searches the first rank radio | wireless terminal by 1st Example of this invention. It is a flowchart for demonstrating the process which determines the position of the mobile base station by the 1st Example of this invention. It is a figure which shows an example which determines the position of the mobile base station by the 1st Example of this invention. It is a block diagram which shows the structure of the terminal location determination system by 1st Example of this invention. It is a flowchart for demonstrating the process which searches the first rank radio | wireless terminal by 2nd Example of this invention. It is a figure which shows an example of the multihop path | route including the first rank radio | wireless terminal which does not connect a radio | wireless terminal to the subordinate by the 2nd Example of this invention.

Explanation of symbols

10: Mobile base station 11: Antenna 12: Transmission / reception selector switch 13: Radio reception unit 14: Demodulation unit 15: Data processing unit 16: Modulation unit 17: Radio transmission unit 18: Reception intensity measurement unit 19: Databases 20, 30, 40 50: Wireless terminals 20a, 30a, 40a, 50a: Sensors 20b, 30b, 40b, 50b: Control device 21: Antenna 22: Transmission / reception selector switch 23: Wireless reception unit 24: Demodulation unit 25: Data processing unit 26: Modulation unit 27: Wireless transmission unit 28: Reception strength measurement unit 29: Battery remaining amount monitoring unit 60, 70, 80, 90: First stage wireless terminal 100: Base station position determination program 110: Wireless terminal

Claims (19)

In a multi-hop wireless network configured with a plurality of wireless terminals and a mobile base station, wherein the wireless terminal relays data communication between the mobile base station and the wireless terminal, for determining the position of the mobile base station A mobile base station location determination system,
In each of a plurality of candidate locations of the mobile base station,
Obtaining the remaining battery power information of each of the plurality of wireless terminals, position information, current balance information indicating a value obtained by subtracting current consumption from charging current, and reception intensity information obtained from wireless signals transmitted from the respective wireless terminals. , Based on the acquired information, select one or more first-stage wireless terminal candidates from the wireless terminals that communicate directly with the mobile base station without relaying;
Based on the candidates for the first stage radio terminal selected at each of the plurality of candidate locations, determine a position to install the mobile base station from the candidate locations ,
When there are a plurality of candidate sites where the mobile base station is installed, the candidate site is selected from among the plurality of candidate sites where the remaining battery power of the first stage wireless terminal is large and the number of first stage wireless terminals is large. Mobile base station position determination system.   When wireless signals for detecting the plurality of wireless terminals are transmitted, battery balance information transmitted from the wireless terminals, position information, and current balance information indicating a value obtained by subtracting current consumption from charging current are transmitted to the mobile base. The communication duration of each wireless terminal is calculated from the battery power remaining amount information and the current balance information received by the station, the communication duration is long, and the reception strength obtained from the wireless signal is higher than a preset threshold value The mobile base station location determination system according to claim 1, wherein a larger wireless terminal is selected as a candidate for the first stage wireless terminal.   The position of the mobile base station is determined based on the location information of the first-stage radio terminal and accessible area information regarding an area where the mobile base station is allowed to enter. Mobile base station location determination system.   When wireless signals for detecting the plurality of wireless terminals are transmitted, battery balance information transmitted from the wireless terminals, position information, and current balance information indicating a value obtained by subtracting current consumption from charging current are transmitted to the mobile base. The communication duration of each wireless terminal is calculated from the battery power remaining amount information and the current balance information received by the station, the communication duration is short, and the reception strength obtained from the wireless signal is higher than a preset threshold value The mobile base station position determination system according to claim 1, wherein a larger wireless terminal is selected as a candidate for the first stage wireless terminal on condition that no wireless terminal is connected to the wireless terminal. A multi-hop wireless network comprising a wireless terminal having a mobile base station function and a plurality of wireless terminals, wherein the wireless terminal relays data communication between the wireless terminal having the mobile base station function and the wireless terminal A terminal position determination system for determining a position of a wireless terminal having the function of the mobile base station,
The wireless terminal having the function of the mobile base station, in each of a plurality of candidate locations of its position,
Obtaining the remaining battery power information of each of the plurality of wireless terminals, position information, current balance information indicating a value obtained by subtracting the consumption current from the charging current, and reception intensity information obtained from the wireless signal transmitted from each wireless terminal. Then, based on the acquired information, select one or more first-stage wireless terminal candidates from the wireless terminals that perform direct communication without relaying with the wireless terminal having the function of the mobile base station,
Based on the candidates for the first stage wireless terminal selected in each of the plurality of candidate locations, determine a position to install a wireless terminal having the function of the mobile base station from among the candidate locations ,
When there are a plurality of candidate sites where wireless terminals having the function of the mobile base station are installed, a candidate site where the remaining battery power of the first stage wireless terminal is large and the number of first stage wireless terminals is large among the plurality of candidate sites. A terminal location determination system characterized by selecting . The location of the mobile base station in a multi-hop wireless network comprising a computer having a mobile base station function and a plurality of wireless terminals, wherein the wireless terminal relays data communication between the mobile base station and the wireless terminal A mobile base station location determination system for determining
In each of a plurality of candidate locations of the location of the mobile base station, the computer
Obtaining the remaining battery power information of each of the plurality of wireless terminals, position information, current balance information indicating a value obtained by subtracting the consumption current from the charging current, and reception intensity information obtained from the wireless signal transmitted from each wireless terminal. , Based on the acquired information, select one or more first-stage wireless terminal candidates from the wireless terminals that communicate directly with the mobile base station without relaying;
Based on the first-stage wireless terminal candidates selected in each of the plurality of candidate locations, determine a position to install the mobile base station from the candidate locations ,
When there are a plurality of candidate sites where the mobile base station is installed, the candidate site is selected from among the plurality of candidate sites where the remaining battery power of the first stage wireless terminal is large and the number of first stage wireless terminals is large. Terminal location determination system. A mobile base station in a multi-hop wireless network that performs data communication by relaying the wireless terminal with a plurality of wireless terminals under its control,
In each of the multiple candidate sites at your location,
Obtaining the remaining battery power information of each of the plurality of wireless terminals, position information, current balance information indicating a value obtained by subtracting the consumption current from the charging current, and reception intensity information obtained from the wireless signal transmitted from each wireless terminal. Then, based on the acquired information, select one or more first-stage wireless terminal candidates from the wireless terminals that perform direct communication without relaying by the wireless terminal,
Based on the candidates for the first stage wireless terminal selected at each of the plurality of candidate locations, determine the position to install from among the candidate locations ,
A mobile base station characterized in that, when there are a plurality of candidate sites to be installed, a candidate site having a large amount of remaining battery power and a large number of first-stage wireless terminals is selected from among the plurality of candidate sites . A wireless signal for detecting a wireless terminal capable of communicating with the plurality of wireless terminals is transmitted, and a value obtained by subtracting current consumption from remaining battery power information, position information, and charging current transmitted from the wireless terminal The current balance information is received, the communication duration of each wireless terminal is calculated from the remaining battery power information and the current balance information, and the communication strength is long and the reception strength obtained from the wireless signal is preset. The mobile base station according to claim 7 , wherein a wireless terminal larger than the threshold value is selected as a candidate for a first-stage wireless terminal. 9. The mobile base station according to claim 8 , wherein a location to be installed is determined based on accessible area information regarding an area where entry is permitted and location information of the first-stage wireless terminal. A wireless signal for detecting a wireless terminal capable of communicating with the plurality of wireless terminals is transmitted, and a value obtained by subtracting current consumption from remaining battery power information, position information, and charging current transmitted from the wireless terminal Current balance information is received, the communication duration of each wireless terminal is calculated from the remaining battery power information and the current balance information, the communication duration is short, and the reception strength obtained from the wireless signal is preset. The mobile base station according to claim 7 , wherein a wireless terminal larger than the threshold value is selected as a candidate for a first-stage wireless terminal on condition that a wireless terminal is not connected to the wireless terminal. A reception strength measurement unit that provides the reception strength information; a data processing unit that selects candidates for first-stage wireless terminals based on the reception strength information, battery power remaining amount information, and position information; and the reception strength information and battery power The mobile base station according to claim 7 , further comprising a database that stores remaining amount information and position information. A wireless terminal having a function of a mobile base station in a multi-hop wireless network that performs data communication by relaying the wireless terminal with a plurality of wireless terminals under its control,
In each of the multiple candidate sites at your location,
Obtaining the remaining battery power information of each of the plurality of wireless terminals, position information, current balance information indicating a value obtained by subtracting the consumption current from the charging current, and reception intensity information obtained from the wireless signal transmitted from each wireless terminal. Then, based on the acquired information, select one or more first-stage wireless terminal candidates from the wireless terminals that perform direct communication without relaying by the wireless terminal,
Based on the candidates for the first stage wireless terminal selected at each of the plurality of candidate locations, determine the position to install from among the candidate locations ,
A radio terminal characterized in that, when there are a plurality of candidate sites to be installed, a candidate site having a large amount of remaining battery power and a large number of first-stage radio terminals is selected from the plurality of candidate sites .   A wireless signal for detecting a wireless terminal capable of communicating with the plurality of wireless terminals is transmitted, and a value obtained by subtracting current consumption from remaining battery power information, position information, and charging current transmitted from the wireless terminal The current balance information is received, the communication duration of each wireless terminal is calculated from the remaining battery power information and the current balance information, and the communication strength is long and the reception strength obtained from the wireless signal is preset. The wireless terminal according to claim 12, wherein a wireless terminal larger than the threshold value is selected as a candidate for the first stage wireless terminal.   The wireless terminal according to claim 13, wherein the installation position is determined based on accessible area information regarding an area where entry is permitted and position information of the first-stage wireless terminal.   A wireless signal for detecting a wireless terminal capable of communicating with the plurality of wireless terminals is transmitted, and a value obtained by subtracting current consumption from remaining battery power information, position information, and charging current transmitted from the wireless terminal Current balance information is received, the communication duration of each wireless terminal is calculated from the remaining battery power information and the current balance information, the communication duration is short, and the reception strength obtained from the wireless signal is preset. The wireless terminal according to claim 12, wherein a wireless terminal larger than the threshold value is selected as a candidate for a first-stage wireless terminal on condition that a wireless terminal is not connected to the wireless terminal.   A reception strength measurement unit that provides the reception strength information; a data processing unit that selects candidates for first-stage wireless terminals based on the reception strength information, battery power remaining amount information, and position information; and the reception strength information and battery power The wireless terminal according to claim 12, further comprising a database that stores remaining amount information and position information. A base station position that is executed on a mobile base station in a multi-hop wireless network that performs data communication of a method of relaying the wireless terminal with a plurality of wireless terminals under its control and determines the position of the mobile base station A decision program,
In each of a plurality of candidate locations of the mobile base station,
Obtaining the remaining battery power information of each of the plurality of wireless terminals, position information, current balance information indicating a value obtained by subtracting the consumption current from the charging current, and reception intensity information obtained from the wireless signal transmitted from each wireless terminal. A function to select one or more first-stage wireless terminal candidates from among the wireless terminals that perform direct communication without relaying by the wireless terminal based on the acquired information;
A function of determining a location to be installed from the candidate locations based on the candidates for the first stage wireless terminal selected in each of the one or more candidate locations ;
When there are a plurality of candidate sites where the mobile base station is installed, a function of selecting a candidate site where the remaining battery power of the first-stage wireless terminal is large and the number of first-stage wireless terminals is large among the plurality of candidate areas A base station position determination program characterized by that. A wireless signal for detecting a wireless terminal capable of communicating with the plurality of wireless terminals is transmitted, and a value obtained by subtracting current consumption from remaining battery power information, position information, and charging current transmitted from the wireless terminal The current balance information is received, the communication duration of each wireless terminal is calculated from the remaining battery power information and the current balance information, and the communication strength is long and the reception strength obtained from the wireless signal is preset. The base station position determination program according to claim 17 , wherein the base station position determination program has a function of selecting a wireless terminal larger than the threshold value as a candidate for a first-stage wireless terminal. 19. The base station position determination program according to claim 18 , wherein the base station position determination program has a function of determining a position to install based on accessible area information regarding an area where entry is permitted and position information of the first-stage wireless terminal.

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