JP7469777B2 - Wireless communication system, wireless base station, and wireless communication method - Google Patents

Description

The present disclosure relates to a wireless communication system, a wireless base station, and a wireless communication method for selecting a wireless base station when the device is battery-powered.

In the event of a disaster, a failure occurs in the commercial power grid throughout the entire region. Even if the power supply from the power grid is stopped during a disaster, the wireless base station equipment in the region is required to maintain its functionality by running on batteries (see, for example, Non-Patent Document 1). When a wireless base station becomes battery-powered, it is necessary to reduce the power consumption of the wireless base station and extend its operating period as long as possible.

For this reason, a method has been proposed to reduce the power consumption of base stations by using sleep control when traffic is not flowing (see, for example, Patent Document 1). Also, in order to optimize the power consumption of base stations even when traffic is flowing, a method has been proposed for controlling the cell size of base stations to maximize user coverage based on a prediction of user distribution (see, for example, Non-Patent Document 2).

Patent No. 5654431, "Base station device and sleep control method for said base station device"

Yasushi Matsuoka, Takashi Yamauchi, Takashi Furuya, Kazuhiko Takeno, "Disaster Countermeasure Backup Power System for Wireless Base Stations Using Fuel Cells," NTT DOCOMO Technical Journal, vol. 21, no. 3, pp. 6-10, October 2013. Kazumasa Kitada, Akira Uchiyama, Teruo Higashino, "Cell Size Control Method for Maximizing Coverage Considering Battery Level of Mobile Phone Base Stations during Disasters," Symposium on Multimedia, Distributed, Cooperative and Mobile (DICOMO2014), pp. 1547-1556, July 2014.

However, the related technology does not take into account the case where a wireless base station and wireless terminals can communicate using multiple communication methods, so while adjusting the coverage area increases overall efficiency, it also has the problem of worsening the wireless communication environment for already connected terminals.

The present disclosure has been made in consideration of these problems, and aims to provide a wireless communication system, a wireless base station, and a wireless communication method that selects a wireless communication base station capable of operating for a longer period from among multiple wireless base stations in battery-powered mode, without adversely affecting the communication environment of already connected wireless terminals, and connects the wireless base station to a wireless terminal.

To achieve the above object, in the wireless communication system, wireless base station, and wireless communication method disclosed herein, in response to a connection request from a wireless terminal, the management server selects a wireless communication base station that can operate the wireless base station for a longer period of time, and instructs the wireless terminal to connect to the selected wireless base station.

Specifically, the wireless communication system according to the present disclosure includes:
The system includes a wireless terminal, a wireless base station, and a management server,
The wireless terminal,
a terminal information/queue management unit that manages its own terminal information and a queue of user traffic and outputs the terminal information when there is user traffic in the queue;
a wireless terminal transmitting unit that wirelessly transmits the terminal information output by the terminal information/queue management unit to the wireless base station;
a wireless terminal receiving unit that wirelessly receives information on a selected base station and information on a selected communication method from the wireless base station;
a wireless terminal control unit that starts communication with a selected wireless base station in a selected communication method based on the selected base station information and the selected communication method information from the wireless terminal receiving unit;
having
The wireless base station
a wireless terminal side receiving unit that wirelessly receives the terminal information from the wireless terminal;
an EPB calculation unit that calculates an EPB (Energy Per Bit) for all communication methods available to the wireless terminal according to formula (1) and creates an EPB table;
EPB = incremental power consumption / estimated throughput (1)
however,
Incremental power consumption: power consumption that increases when a new wireless terminal is connected. Estimated throughput: available bit rate of the newly connected wireless terminal. A communication method selection unit that selects a communication method with the smallest EPB by referring to the EPB table created by the EPB calculation unit.
an RB calculation unit that calculates an RB (Residual Bit) according to equation (2) for the communication method selected by the communication method selection unit and outputs the RB information;
RB = remaining battery power / EPB (2)
however,
A management server side transmission unit that transmits to the management server the terminal information received from the wireless terminal, the base station information of the wireless terminal itself, and the RB information output by the RB calculation unit;
a management server side receiving unit that receives selection information including whether or not the management server is selected as a wireless base station for communication from the management server;
a communication control unit which refers to the selection information from the management server side receiving unit to determine whether or not communication has been started, and if the own station has been selected, outputs base station information of the own station as the selected base station information and information on the selected communication method from the communication method selection unit, and starts communication with the corresponding wireless terminal using the selected communication method, and if the own station has not been selected, ends the process;
a wireless terminal side transmitting unit that wirelessly transmits the selected base station information and the selected communication method information output by the communication control unit to a corresponding wireless terminal;
having
The management server includes:
a management server receiving unit that receives the terminal information, the base station information, and the RB information from the radio base station and creates an RB table that summarizes the RB information of each radio base station;
a base station selection unit that refers to the RB table created by the management server receiving unit, selects a wireless base station with the largest RB, and outputs the selected base station as selection information;
a management server transmission unit that transmits the selection information from the base station selection unit to the wireless base station;
The present invention is characterized by having the following.

Specifically, the radio base station according to the present disclosure includes:
A wireless base station that is selected by a management server and wirelessly communicates with a wireless terminal,
a wireless terminal side receiving unit that wirelessly receives terminal information from a wireless terminal;
an EPB calculation unit that calculates an EPB (Energy Per Bit) for all communication methods available to the wireless terminal according to formula (1) and creates an EPB table;
EPB = incremental power consumption / estimated throughput (1)
however,
Incremental power consumption: power consumption that increases when a new wireless terminal is connected. Estimated throughput: available bit rate of the newly connected wireless terminal. A communication method selection unit that selects a communication method with the smallest EPB by referring to the EPB table created by the EPB calculation unit.
an RB calculation unit that calculates an RB (Residual Bit) according to equation (2) for the communication method selected by the communication method selection unit and outputs the RB information;
RB = remaining battery power / EPB (2)
however,
A management server side transmitting unit that transmits to a management server the terminal information received from the wireless terminal, the base station information of the wireless terminal itself, and the RB information output by the RB calculation unit;
a management server side receiving unit that receives selection information including whether or not the management server is selected as a wireless base station for communication from the management server;
a communication control unit which refers to the selection information from the management server side receiving unit to determine whether or not communication has been started, and if the own station has been selected, outputs base station information of the own station as selected base station information and information on the selected communication method from the communication method selection unit, and starts communication with the corresponding wireless terminal using the selected communication method, and if the own station has not been selected, ends the process;
a wireless terminal side transmitting unit that wirelessly transmits the selected base station information and the selected communication method information output by the communication control unit to a corresponding wireless terminal;
The present invention is characterized by having the following.

Specifically, the wireless communication method according to the present disclosure includes:
The wireless terminal
Manages its own terminal information and a queue of user traffic, and when there is user traffic in the queue, wirelessly transmits the terminal information to a wireless base station;
The wireless base station,
wirelessly receiving the terminal information from the wireless terminal;
Calculate EPB (Energy Per Bit) for all communication methods available to the wireless terminal according to formula (1), and create an EPB table;
EPB = incremental power consumption / estimated throughput (1)
however,
Incremental power consumption: power consumption that increases when a new wireless terminal is connected. Estimated throughput: available bit rate of the newly connected wireless terminal. Referring to the created EPB table, a communication method with the smallest EPB is selected.
Calculate RB (Residual Bit) for the selected communication method according to formula (2) and output it as RB information;
RB = remaining battery power / EPB (2)
however,
Battery remaining capacity: remaining power capacity of a battery power source connected to a base station. The terminal information, the base station information of the wireless terminal itself, and the RB information received from the wireless terminal are transmitted to a management server;
The management server includes:
receiving the terminal information, the base station information, and the RB information from the radio base station, and creating an RB table that summarizes the RB information of each radio base station;
Refer to the created RB table to select a radio base station with the largest RB, and transmit the selection information including the selection or non-selection of the radio base station as a communication radio base station to the radio base station;
The wireless base station
receiving the selection information from the management server;
With reference to the selection information, determine whether or not communication is to be started, and if the own station is selected, wirelessly transmit base station information of the own station as selected base station information and information on the selected communication method to a corresponding wireless terminal, and start communication with the corresponding wireless terminal using the selected communication method, and if the own station is not selected, terminate the process;
The wireless terminal,
wirelessly receiving the selected base station information and the selected communication method information from the wireless base station;
The method is characterized in that communication is started with the selected wireless base station in the selected communication method based on the selected base station information and the selected communication method information.

The wireless communication system, wireless base station, and wireless communication method disclosed herein can select a wireless communication base station capable of operating for a longer period of time from among multiple wireless base stations that are battery-powered, without adversely affecting the communication environment of an already connected wireless terminal, and can connect the wireless base station to the wireless terminal.

FIG. 1 is a diagram illustrating a configuration of a wireless communication system. FIG. 2 is a diagram illustrating the configuration of a wireless terminal. FIG. 2 is a diagram illustrating the configuration of a wireless base station. 1 is an example of an EPB table of a wireless base station. 1 is an example of an EPB table of a wireless base station. FIG. 2 is a diagram illustrating a configuration of a management server. 13 is an example of an RB table of a management server.

The following describes in detail the embodiments of the present disclosure with reference to the drawings. Note that the present disclosure is not limited to the embodiments shown below. These implementation examples are merely illustrative, and the present disclosure can be implemented in various forms with various modifications and improvements based on the knowledge of those skilled in the art. Note that components with the same reference numerals in this specification and drawings are considered to be identical to each other.

First Embodiment
1 is a diagram illustrating the configuration of a wireless communication system according to the present disclosure, in which 10 is a wireless terminal, 20 is a wireless base station, and 30 is a management server.

Figure 2 is a diagram illustrating the configuration of a wireless terminal of the present disclosure. In Figure 2, the wireless terminal 10 has a terminal information/queue management unit 11, a wireless terminal transmission unit 12, a wireless terminal reception unit 13, and a wireless terminal control unit 14.

The terminal information/queue management unit 11 manages its own terminal information and the queue of user traffic, and outputs terminal information when there is user traffic in the queue. The wireless terminal transmission unit 12 wirelessly transmits the terminal information output by the terminal information/queue management unit 11 to the wireless base station 20. The wireless terminal reception unit 13 wirelessly receives the selected base station information and information on the selected communication method from the wireless base station 20. The wireless terminal control unit 14 starts communication with the selected wireless base station using the selected communication method based on the selected base station information and information on the selected communication method from the wireless terminal reception unit 13.

Figure 3 is a diagram illustrating the configuration of a wireless base station according to the present disclosure. In Figure 3, the wireless base station 20 has a wireless terminal side receiver 21, an EPB calculation unit 22, an EPB table 23, a communication method selection unit 24, an RB calculation unit 25, a management server side transmitter 26, a management server side receiver 27, a communication control unit 28, and a wireless terminal side transmitter 29.

The wireless terminal side receiving unit 21 wirelessly receives terminal information from the wireless terminal 10. The EPB calculation unit 22 calculates EPB (Energy Per Bit) for all communication methods usable by the wireless terminal 10 according to formula (1), and creates an EPB table 23.
EPB = incremental power consumption / estimated throughput (1)
however,
Incremental power consumption: The power consumption that increases when a new wireless terminal is connected. Estimated throughput: The available bit rate of the newly connected wireless terminal.

The incremental power consumption can be calculated by measuring the power consumption when attempting to connect using each communication method in sequence, and calculating the difference from the power consumption before connection. The estimated throughput is the estimated throughput of the newly connecting wireless terminal, and is the bit rate that the wireless terminal can use when connecting using each communication method.

Examples of the EPB table 23 are shown in Figures 4 and 5. Figure 4 is an example of an EPB table created by wireless base station No. 1, and Figure 5 is an example of an EPB table created by wireless base station No. 2. In Figures 4 and 5, wireless terminal identifiers are provided to identify which wireless terminal is making a communication request. In the EPB table of wireless base station No. 1 in Figure 4, the wireless terminal represented by wireless terminal identifier 1 is capable of communication methods 1 and 2, and the respective EPBs are EPB11 and EPB12.

The wireless terminal 10 is located not only in the wireless communication area of wireless base station No. 1, but also in the wireless communication area of wireless base station No. 2. In the EPB table of wireless base station No. 2 in FIG. 5, the wireless terminal represented by wireless terminal identifier 1 is capable of communication methods 2 and 3, and the EPBs for each are EPB21 and EPB22.

The communication method selection unit 24 selects the communication method with the smallest EPB by referring to the EPB table 23 created by the EPB calculation unit 22. For example, if EPB11>EPB12 in the EPB table of FIG. 4 and EPB21>EPB22 in the EPB table of FIG. 5, communication method 2 is selected for wireless base station No. 1 and communication method 3 is selected for wireless base station No. 2.

The RB calculation unit 25 calculates an RB (Residual Bit) for the communication method selected by the communication method selection unit 24 according to equation (2), and outputs it as RB information.
RB = remaining battery power / EPB (2)
however,
Battery remaining: The remaining power of the battery power source connected to the base station

The management server side transmission unit 26 transmits the terminal information received from the wireless terminal 10, the base station information of the own station, and the RB information output by the RB calculation unit 25 to the management server 30. When the communication method selection unit 24 selects the communication method with the smallest EPB, the management server side transmission unit 26 may also transmit information on the selected communication method to the management server 30.

The management server side receiving unit 27 receives selection information from the management server 30, including whether or not the wireless base station has been selected for communication. The communication control unit 28 refers to the selection information from the management server side receiving unit 27 to determine whether or not communication should be started, and if the own station has been selected, outputs the base station information of the own station as the selected base station information and the information of the selected communication method from the communication method selecting unit 24, and starts communication with the corresponding wireless terminal 10 using the selected communication method. The wireless terminal side transmitting unit 29 wirelessly transmits the selected base station information and the information of the selected communication method output by the communication control unit 28 to the corresponding wireless terminal 10. If the own station has not been selected, the communication control unit 28 deletes the EPB table and terminates the connection with the corresponding wireless terminal 10.

Figure 6 is a diagram illustrating the configuration of the management server of the present disclosure. In Figure 6, the management server 30 has a management server receiving unit 31, an RB table 32, a base station selecting unit 33, and a management server transmitting unit 34.

The management server receiving unit 31 receives terminal information, base station information, and RB information from the wireless base station 20, and creates an RB table 32 that summarizes the RB information of each base station. When the management server side transmitting unit 26 of the wireless base station 20 also transmits information on the selected communication method and the management server receiving unit 31 receives the communication method information, the management server receiving unit 31 may also add an item for the communication method information to the RB table 32. When the RB table 32 contains communication method information, the management server 30 can also manage the communication method for wireless communication between the wireless base station 20 and the wireless terminal 10.

An example of the RB table 32 of the management server 30 is shown in FIG. 7. In FIG. 7, a wireless terminal 10 with wireless terminal identifier 1 is located in the areas of two wireless base stations, and therefore receives RB information from the wireless base station with base station identifier 1 and the wireless base station with base station identifier 2. For the wireless terminal with wireless terminal identifier 1 received from the wireless base station with base station identifier 1, communication method 2 is selected as the communication method, and the RB at this time is RB1. Similarly, for the wireless terminal with wireless terminal identifier 1 received from the wireless base station with base station identifier 2, communication method 3 is selected as the communication method, and the RB at this time is RB2.

The base station selection unit 33 refers to the RB table 32 created by the management server reception unit 31, selects the wireless base station with the largest RB, and outputs it as selection information. For example, in the RB table of FIG. 7, if RB1>RB2, wireless base station No. 1 is selected, and communication method 2 is selected as the communication method.

The management server transmitting unit 34 transmits the selection information from the base station selecting unit 33 to the wireless base station 20. If there are multiple wireless base stations, the management server transmitting unit 34 transmits the selection information to the wireless base station received by the management server receiving unit 31. At this time, the information on the selected communication method received from the wireless base station 20 may be returned to the same wireless base station 20. The wireless base station 20 that receives the communication method information can confirm the communication method.

The operation of the above wireless communication system will be explained step by step with reference to FIG.
First Step: The wireless terminal 10 manages its own terminal information and a queue of user traffic, and when there is user traffic in the queue, it wirelessly transmits the terminal information to the wireless base station 20 (A in FIG. 1).

Second step: The wireless base station 20 wirelessly receives terminal information from the wireless terminal 10 (A in FIG. 1), calculates EPB (Energy Per Bit) for all communication methods usable by the wireless terminal 10 according to formula (1), and creates an EPB table (FIGS. 4 and 5).
EPB = incremental power consumption / estimated throughput (1)
however,
Incremental power consumption: The power consumption that increases when a new wireless terminal is connected. Estimated throughput: The available bit rate of the newly connected wireless terminal.

The wireless base station 20 refers to the created EPB table, selects the communication method with the smallest EPB, calculates the RB (Residual Bit) for the selected communication method according to equation (2), and outputs it as RB information.
RB = remaining battery power / EPB (2)
however,
Battery remaining: The remaining power of the battery power source connected to the base station

The wireless base station 20 transmits the terminal information, its own base station information, and RB information received from the wireless terminal 10 to the management server 30 (B in FIG. 1). When the wireless base station 20 selects the communication method with the smallest EPB, it may also transmit information about the selected communication method to the management server 30.

Third step: The management server 30 receives terminal information, base station information, and RB information from the wireless base station 20 (B in FIG. 1), and creates an RB table (FIG. 7) that summarizes the RB information of each base station. The management server 30 refers to the created RB table, selects the base station with the largest RB, and transmits it to the wireless base station as selection information (C in FIG. 1). When the wireless base station 20 also transmits information on the communication method and the management server 30 receives the information on the communication method, an item on the communication method may also be added to the RB table. If the RB table contains information on the communication method, the management server 30 can also manage the communication method for wireless communication between the wireless base station 20 and the wireless terminal 10.

Step 4: The wireless base station 20 receives selection information including whether or not it has been selected as a wireless base station to communicate with from the management server 30 (C in FIG. 1), and judges whether or not to start communication by referring to the selection information. If the wireless base station 20 is selected, it wirelessly transmits its base station information as the selected base station information and information on the selected communication method to the corresponding wireless terminal (D in FIG. 1). The wireless base station 20 starts communication with the corresponding wireless terminal using the selected communication method, and if the wireless base station 20 is not selected, ends the process.

Fifth step: The wireless terminal 10 wirelessly receives the selected base station information and the selected communication method information from the wireless base station (D in FIG. 1). Based on the selected base station information and the selected communication method information, the wireless terminal 10 starts communication with the selected wireless base station 20 in the selected communication method.

As described above, the wireless communication system, wireless base station, and wireless communication method disclosed herein can select a wireless communication base station capable of operating for a longer period of time from among multiple wireless base stations in battery-powered mode, without adversely affecting the communication environment of an already connected wireless terminal, and connect the wireless base station to the wireless terminal.

Second Embodiment
In the present disclosure, new functions are added to the wireless communication system and wireless base station of the first embodiment.
1, when user data traffic that needs to meet a deadline accumulates in a queue, a terminal information/queue management unit 11 of a wireless terminal 10 also outputs required throughput information. When the terminal information/queue management unit 11 outputs the required throughput information, a wireless terminal transmission unit 12 of the wireless terminal 10 also wirelessly transmits the required throughput information to a wireless base station 20.

In FIG. 2, the wireless terminal side receiver 21 of the wireless base station 20 also wirelessly receives required throughput information from the wireless terminal. When the required throughput is input from the wireless terminal side receiver 21, the EPB calculation unit 22 adds only the communication methods that can complete communication at the required throughput to the EPB table (FIGS. 4 and 5).

In the present disclosure, a new operation is added to the wireless communication method of the first embodiment.
In the first step of the first embodiment, when user data traffic that needs to meet a deadline accumulates in a queue, the wireless terminal 10 also wirelessly transmits required throughput information to the wireless base station 20 (A in FIG. 1).

In the second step of the first embodiment, when the wireless base station 20 wirelessly receives the required throughput information, it adds only the communication methods that can complete communication at the required throughput to the EPB table (Figures 4 and 5).

As described above, the wireless communication system, wireless base station, and wireless communication method disclosed herein can facilitate the selection of a communication method and prevent communication interruptions midway by eliminating communication methods that cannot complete communication at the required throughput. Furthermore, it is possible to select a wireless communication base station that can operate the wireless base station for a longer period of time from multiple wireless base stations that are in battery-powered mode, and connect the wireless base station to the wireless terminal, without adversely affecting the communication environment of the already connected wireless terminal.

In the wireless communication system, wireless base station, and wireless communication method disclosed herein, a wireless terminal is shown to be connectable to two wireless base stations, but the present disclosure can be applied to any number of wireless base stations. Also, in the wireless communication system, wireless base station, and wireless communication method disclosed herein, a wireless base station and a communication method are selected when a connection is started, but they may be selected periodically.

The device disclosed herein can also be realized by a computer and a computer program, and the computer program can be recorded on a recording medium or provided through a communication network. Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit and scope of the present invention.

This invention is not limited to the above-described embodiment as it is, and in the implementation stage, the components can be modified to the extent that does not deviate from the gist of the invention. In addition, various inventions can be formed by appropriately combining multiple components disclosed in the above-described embodiment. For example, some components may be deleted from all of the components shown in the embodiment. Furthermore, components from different embodiments may be appropriately combined.

This disclosure can be applied to the information and communications industry.

10: Wireless terminal 11: Terminal information/queue management unit 12: Wireless terminal transmission unit 13: Wireless terminal reception unit 14: Wireless terminal control unit 20: Wireless base station 21: Wireless terminal side reception unit 22: EPB calculation unit 23: EPB table 24: Communication method selection unit 25: RB calculation unit 26: Management server side transmission unit 27: Management server side reception unit 28: Communication control unit 29: Wireless terminal side transmission unit 30: Management server 31: Management server reception unit 32: RB table 33: Base station selection unit 34: Management server transmission unit

Claims (8)

A wireless terminal, a wireless base station, and a management server are provided,
The wireless terminal,
a terminal information/queue management unit that manages its own terminal information and a queue of user traffic and outputs the terminal information when there is user traffic in the queue;
a wireless terminal transmitting unit that wirelessly transmits the terminal information output by the terminal information/queue management unit to the wireless base station;
a wireless terminal receiving unit that wirelessly receives information on a selected base station and information on a selected communication method from the wireless base station;
a wireless terminal control unit that starts communication with a selected wireless base station in a selected communication method based on the selected base station information and the selected communication method information from the wireless terminal receiving unit;
having
The wireless base station
a wireless terminal side receiving unit that wirelessly receives the terminal information from the wireless terminal;
an EPB calculation unit that calculates an EPB (Energy Per Bit) for all communication methods available to the wireless terminal according to formula (1) and creates an EPB table;
EPB = incremental power consumption / estimated throughput (1)
however,
Incremental power consumption: power consumption that increases when a new wireless terminal is connected. Estimated throughput: available bit rate of the newly connected wireless terminal. A communication method selection unit that selects a communication method with the smallest EPB by referring to the EPB table created by the EPB calculation unit.
an RB calculation unit that calculates an RB (Residual Bit) according to equation (2) for the communication method selected by the communication method selection unit and outputs the RB information;
RB = remaining battery power / EPB (2)
however,
A management server side transmission unit that transmits to the management server the terminal information received from the wireless terminal, the base station information of the wireless terminal itself, and the RB information output by the RB calculation unit;
a management server side receiving unit that receives selection information including whether or not the management server is selected as a wireless base station for communication from the management server;
a communication control unit which refers to the selection information from the management server side receiving unit to determine whether or not communication has been started, and if the own station has been selected, outputs base station information of the own station as the selected base station information and information on the selected communication method from the communication method selection unit, and starts communication with the corresponding wireless terminal using the selected communication method, and if the own station has not been selected, ends the process;
a wireless terminal side transmitting unit that wirelessly transmits the selected base station information and the selected communication method information output by the communication control unit to a corresponding wireless terminal;
having
The management server includes:
a management server receiving unit that receives the terminal information, the base station information, and the RB information from the radio base station and creates an RB table that summarizes the RB information of each radio base station;
a base station selection unit that refers to the RB table created by the management server receiving unit, selects a wireless base station with the largest RB, and outputs the selected base station as selection information;
a management server transmission unit that transmits the selection information from the base station selection unit to the wireless base station;
A wireless communication system comprising: the terminal information/queue management unit of the wireless terminal also outputs required throughput information when user data traffic that needs to meet a deadline is accumulated in the queue;
When the terminal information/queue management unit outputs the required throughput information, the wireless terminal transmission unit of the wireless terminal also wirelessly transmits the required throughput information to the wireless base station;
The wireless terminal side receiving unit of the wireless base station also wirelessly receives the required throughput information from the wireless terminal,
an EPB calculation unit of the wireless base station, when receiving required throughput information from the wireless terminal side receiving unit, adds to the EPB table only a communication method that can complete communication with the required throughput;
2. The wireless communication system according to claim 1 . the management server side transmitting unit of the wireless base station also transmits information on the communication method selected by the communication method selecting unit to the management server;
3. The wireless communication system according to claim 1, wherein the management server receiving unit of the management server also adds an item of the information on the communication method to the RB table when the management server receiving unit also receives the information on the communication method. A wireless base station that is selected by a management server and wirelessly communicates with a wireless terminal,
a wireless terminal side receiving unit that wirelessly receives terminal information from a wireless terminal;
an EPB calculation unit that calculates an EPB (Energy Per Bit) for all communication methods available to the wireless terminal according to formula (1) and creates an EPB table;
EPB = incremental power consumption / estimated throughput (1)
however,
Incremental power consumption: power consumption that increases when a new wireless terminal is connected. Estimated throughput: available bit rate of the newly connected wireless terminal. A communication method selection unit that selects a communication method with the smallest EPB by referring to the EPB table created by the EPB calculation unit.
an RB calculation unit that calculates an RB (Residual Bit) according to equation (2) for the communication method selected by the communication method selection unit and outputs the RB information;
RB = remaining battery power / EPB (2)
however,
A management server side transmitting unit that transmits to a management server the terminal information received from the wireless terminal, the base station information of the wireless terminal itself, and the RB information output by the RB calculation unit;
a management server side receiving unit that receives selection information including whether or not the management server is selected as a wireless base station for communication from the management server;
a communication control unit which refers to the selection information from the management server side receiving unit to determine whether or not communication has been started, and if the own station has been selected, outputs base station information of the own station as selected base station information and information on the selected communication method from the communication method selection unit, and starts communication with the corresponding wireless terminal using the selected communication method, and if the own station has not been selected, ends the process;
a wireless terminal side transmitting unit that wirelessly transmits the selected base station information and the selected communication method information output by the communication control unit to a corresponding wireless terminal;
A radio base station comprising: When the wireless terminal also wirelessly transmits required throughput information to the wireless base station,
The wireless terminal side receiving unit of the wireless base station also wirelessly receives the required throughput information from the wireless terminal,
an EPB calculation unit of the wireless base station, when receiving the required throughput from the wireless terminal side receiving unit, adds to the EPB table only a communication method that can complete communication at the required throughput;
5. The radio base station according to claim 4. 6. The wireless base station according to claim 4, wherein the management server side transmitting section also transmits information about the communication method selected by the communication method selecting section to the management server. The wireless terminal
Manages its own terminal information and a queue of user traffic, and when there is user traffic in the queue, wirelessly transmits the terminal information to a wireless base station;
The wireless base station,
wirelessly receiving the terminal information from the wireless terminal;
Calculate EPB (Energy Per Bit) for all communication methods available to the wireless terminal according to formula (1), and create an EPB table;
EPB = incremental power consumption / estimated throughput (1)
however,
Incremental power consumption: power consumption that increases when a new wireless terminal is connected. Estimated throughput: available bit rate of the newly connected wireless terminal. Referring to the created EPB table, a communication method with the smallest EPB is selected.
Calculate RB (Residual Bit) for the selected communication method according to formula (2) and output it as RB information;
RB = remaining battery power / EPB (2)
however,
Battery remaining capacity: remaining power capacity of a battery power source connected to a base station. The terminal information, the base station information of the wireless terminal itself, and the RB information received from the wireless terminal are transmitted to a management server;
The management server includes:
receiving the terminal information, the base station information, and the RB information from the radio base station, and creating an RB table that summarizes the RB information of each radio base station;
Refer to the created RB table to select a radio base station with the largest RB, and transmit the selection information including the selection or non-selection of the radio base station as a communication radio base station to the radio base station;
The wireless base station
receiving the selection information from the management server;
With reference to the selection information, determine whether or not communication is to be started, and if the own station is selected, wirelessly transmit base station information of the own station as selected base station information and information on the selected communication method to a corresponding wireless terminal, and start communication with the corresponding wireless terminal using the selected communication method, and if the own station is not selected, terminate the process;
The wireless terminal,
wirelessly receiving the selected base station information and the selected communication method information from the wireless base station;
A wireless communication method, comprising starting communication with a selected wireless base station in a selected communication method based on the selected base station information and the selected communication method information. When user data traffic that needs to meet a deadline is accumulated in the queue, the wireless terminal also wirelessly transmits required throughput information to the wireless base station;
When the wireless base station wirelessly receives the required throughput information, the wireless base station adds only a communication method that can complete communication at the required throughput to the EPB table.
8. The wireless communication method according to claim 7.

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