Control device, control method, and program

Abstract

In this control device, an acquisition unit acquires "information on the power used for communication" between each of a plurality of candidate wireless stations to which a terminal is connected and the terminal. In this control device, on the basis of the "information on the power used for communication" acquired by the acquisition unit, a selection unit selects, from among the plurality of candidate wireless stations, a candidate wireless station having a relatively small environmental load as the target wireless station to which the terminal is connected.

Description

Control device, control method, and program

[0001] The present disclosure relates to a control device, a control method, and a program.

[0002] Patent Document 1 discloses a technology for charging a terminal by preferentially using power generated using renewable energy.

[0003] JP 2013-143678 A

[0004] However, Patent Document 1 does not take into consideration the environmental load caused when terminals communicate.

[0005] An object of the present disclosure is to provide a control device, a control method, and a program that can realize communication with reduced environmental impact.

[0006] In one aspect, the control device includes: an acquisition unit that acquires information regarding the power used for communication between each of a plurality of candidate wireless stations to which the terminal is to connect and the terminal; and a selection unit that selects, based on the acquired information regarding power, from among the plurality of candidate wireless stations, a candidate wireless station with a relatively small environmental load as the wireless station to which the terminal is to connect.

[0007] In another aspect, the control method is a control method executed by a control device, and includes: acquiring information regarding power used for communication between each of a plurality of candidate wireless stations to which a terminal is to connect and the terminal; and selecting, based on the acquired information regarding power, a candidate wireless station with a relatively small environmental load from among the plurality of candidate wireless stations, as a wireless station to which the terminal is to connect.

[0008] In another aspect, the program causes the control device to execute a process including: acquiring information regarding the power used for communication between each of a plurality of candidate wireless stations to which the terminal is to connect and the terminal; and selecting, based on the acquired information regarding power, a candidate wireless station with a relatively small environmental load from among the plurality of candidate wireless stations, as a wireless station to which the terminal is to connect.

[0009] The present disclosure makes it possible to provide a control device, a terminal, a control method, and a program that can realize communication with reduced environmental impact.

[0010] 1 is a block diagram showing an example of a control device of the present disclosure. FIG. 2 is a diagram showing an example of a communication system of the present disclosure. FIG. 3 is a block diagram showing an example of a base station of the present disclosure. FIG. 4 is a block diagram showing an example of a terminal of the present disclosure. FIG. 5 is a flowchart showing an example of processing operation of a control device of the present disclosure. FIG. 6 is a block diagram showing another example of a terminal of the present disclosure. FIG. 7 is a block diagram showing another example of a terminal of the present disclosure. FIG. 8 is a block diagram showing another example of a base station of the present disclosure. FIG. 9 is a block diagram showing another example of a terminal of the present disclosure. FIG. 10 is a diagram showing an example of the hardware configuration of a control device. FIG. 11 is a diagram showing an example of the hardware configuration of a terminal. FIG. 12 is a diagram showing an example of the hardware configuration of a base station.

[0011] Hereinafter, embodiments will be described with reference to the drawings. In this disclosure, the drawings may relate to one or more embodiments. Furthermore, each element in the drawings may apply to one or more embodiments. Furthermore, in the embodiments, identical or equivalent elements are given the same reference numerals, and redundant description will be omitted.

[0012] First Embodiment Fig. 1 is a block diagram showing an example of a control device according to the present disclosure. In Fig. 1, the control device 10 includes an acquisition unit 11 and a selection unit 12. The control device 10 may be mounted on a terminal (not shown), or may be connected to the terminal (not shown) by wire or wirelessly, for example.

[0013] The acquisition unit 11 acquires "information about power used for communication" between a terminal (not shown) and each of a plurality of candidate wireless stations (not shown) to which the terminal is to connect. The plurality of candidate wireless stations may include at least one of a 3GPP (registered trademark) base station (e.g., NB (NodeB), eNB (eNodeB), gNB (next generation NodeB)) and a wireless LAN access point. In the following description, it is assumed that all of the plurality of candidate wireless stations are 3GPP base stations.

[0014] Based on the acquired "information on power used for communication," the selector 12 selects, from among the multiple candidate wireless stations, a candidate wireless station with a relatively small environmental impact as a wireless station to which the terminal is to be connected. For example, it goes without saying that the smaller the power consumption for communication, the smaller the environmental impact caused by the communication tends to be. Also, the more the power used for communication is generated by an environmentally friendly power generation method, the smaller the environmental impact caused by the communication tends to be.

[0015] As described above, according to the first embodiment, the selection unit 12 in the control device 10 selects, from among a plurality of candidate wireless stations, a candidate wireless station with a relatively small environmental load as a wireless station to which the terminal is to be connected, based on the “information on the power used for communication” acquired by the acquisition unit 11.

[0016] This configuration of the control device 10 enables the control device 10 to select a candidate wireless station that has a relatively small environmental load as a wireless station to which the terminal is to be connected, thereby enabling the control device 10 to realize communication with a reduced environmental load.

[0017] The selector 12 may select a target wireless station for connection to the terminal from among candidate wireless stations whose environmental loads are equal to or less than a predetermined level, for example. If the environmental loads of all candidate wireless stations are greater than the predetermined level, the selector 12 may not select a target wireless station for connection to the terminal.

[0018] Second Embodiment The second embodiment relates to an example of "information on power used for communication."

[0019] <Configuration Example of a Communication System> FIG. 2 is a diagram illustrating an example of a communication system according to the present disclosure. In FIG. 2, the communication system 1 includes a terminal 20 and base stations (radio stations) 30-1 to 30-3. Hereinafter, when the base stations 30-1 to 30-3 are not distinguished from one another, the base stations 30-1 to 30-3 may be collectively referred to simply as base station 30. Also, in FIG. 2, the terminal 20 is located in an area where the areas of cells C1, C2, and C3 overlap. Therefore, the terminal 20 can receive reference signals transmitted from each of the base stations 30-1 to 30-3 and including information indicating the transmitting base station 30 (e.g., base station identification information, cell identification information). Although FIG. 2 depicts three base stations 30, the number of base stations 30 included in the communication system 1 is not limited to three. The terminal 20 may be located in an area where multiple cells overlap as shown in FIG. 2, or it may be located in the area of ​​a single cell that does not overlap with the area of ​​any other cell.

[0020] <Configuration Example of Base Station> Fig. 3 is a block diagram showing an example of a base station according to the present disclosure. In Fig. 3, a base station 30 includes a communication unit 31, a control unit 32, a network interface unit 33, and a storage unit 34.

[0021] The control unit 32 transmits the above-mentioned "information regarding the power used for communication" to the terminal 20 via the communication unit 31. In the second embodiment, the "information regarding the power used for communication" may include, for example, information indicating whether the base station 30 is a base station that uses power generated by renewable energy. For example, the "information regarding the power used for communication" may include information regarding the power generation method of the power source that supplies power to the base station 30. The information regarding the power generation method may indicate, for example, solar power generation or thermal power generation. The "information regarding the power used for communication" may be stored in the storage unit 34. For example, the "information regarding the power used for communication" may be stored in the storage unit 34 when the base station 30 is installed.

[0022] The control unit 32 may generate a broadcast signal including the above-mentioned "information related to power used for communication" and information indicating the base station 30 (for example, base station identification information, cell identification information), and transmit this broadcast signal via the communication unit 31. Hereinafter, this broadcast signal may be referred to as a "first broadcast signal."

[0023] Furthermore, the control unit 32 may generate a broadcast signal including information indicating the base station 30 (e.g., base station identification information, cell identification information), and transmit this broadcast signal via the communication unit 31. Hereinafter, this broadcast signal may be referred to as a "second broadcast signal." The second broadcast signal may be, for example, a reference signal.

[0024] The network interface unit 33 transmits signals to network nodes other than the base station 30 (for example, other base stations 30, core network devices, etc.). The network interface unit 33 also receives signals from network nodes other than the base station 30 (for example, other base stations 30, core network devices, etc.).

[0025] <Configuration example of terminal> Fig. 4 is a block diagram showing an example of a terminal according to the present disclosure. In Fig. 4, the terminal 20 includes a communication unit 21, a detection unit 22, an extraction unit 23, and the control device 10.

[0026] The communication unit 21 receives a signal transmitted from the base station 30. The communication unit 21 then outputs the received signal to the detection unit 22 and extraction unit 23.

[0027] The detection unit 22 receives a received signal from the communication unit 21. Then, the detection unit 22 detects (measures) the received signal strength of a "second broadcast signal" included in the received signal. Furthermore, the detection unit 22 detects information indicating the base station 30 that transmitted the second broadcast signal, based on the "second broadcast signal" included in the received signal. Here, the base station 30 that transmitted the second broadcast signal, corresponding to a received signal strength equal to or greater than a predetermined threshold (hereinafter sometimes referred to as a "first threshold"), corresponds to the above-mentioned candidate wireless station. Here, it is assumed that each of the base stations 30-1 to 30-3 is a candidate wireless station (i.e., a candidate base station). Note that the detection unit 22 may identify the candidate wireless station based on an average value obtained by averaging the received signal strength over a predetermined period and the first threshold.

[0028] Then, the detection unit 22 outputs information indicating the candidate base stations to the control device 10 .

[0029] The extraction unit 23 receives a received signal from the communication unit 21. Then, the extraction unit 23 extracts a "first broadcast signal" included in the received signal. Then, the extraction unit 23 outputs the above-mentioned "information related to the power used for communication" and information indicating the source base station 30, which are included in the "first broadcast signal," to the control device 10. Note that the processing by the detection unit 22 and the extraction unit 23 may be performed repeatedly periodically.

[0030] The acquisition unit 11 of the control device 10 receives information indicating candidate base stations from the detection unit 22. The acquisition unit 11 also receives the above-mentioned "information related to power used for communication" and information indicating the source base station 30 from the extraction unit 23. This allows the acquisition unit 11 to acquire "information related to power used for communication" of each candidate base station. Note that when the processes of the detection unit 22 and the extraction unit 23 are repeatedly performed periodically, the acquisition unit 11 can repeatedly acquire "information related to power used for communication" of each candidate base station periodically.

[0031] Based on the "information regarding the power used for communication" acquired by the acquisition unit 11, the selection unit 12 selects, from among the plurality of candidate base stations (i.e., base stations 30-1 to 30-3), a candidate base station with a relatively small environmental impact as a "target base station for connection" for the terminal 20. Here, as described above, the "information regarding the power used for communication" in the second embodiment may include information indicating whether the base station 30 is a base station that uses power generated by renewable energy. Therefore, the selection unit 12 may select, from among the plurality of candidate base stations (i.e., base stations 30-1 to 30-3), a candidate base station that uses power generated by renewable energy as a target base station for connection. For example, it is assumed that the power generation method of the power source of base station 30-1 is solar power generation. Also, it is assumed that the power generation method of the power sources of base stations 30-2 and 30-3 is thermal power generation. In this case, base station 30-1 is selected as the target base station for connection.

[0032] Then, the communication unit 21 starts communication (for example, data communication) with the base station 30 selected as the connection target base station.

[0033] <Example of Terminal Operation> An example of the processing operation of the terminal 20 having the above configuration will be described. In particular, the processing operation of the control device 10 will be described here. Fig. 5 is a flowchart showing an example of the processing operation of the control device of the present disclosure. The processing flow shown in Fig. 5 may be executed when triggered by a change in one or more candidate base stations for the terminal 20.

[0034] The acquisition unit 11 acquires "information on power used for communication" of a plurality of candidate base stations (i.e., base stations 30-1 to 30-3) (step S11). As described above, the "information on power used for communication" in the second embodiment is, for example, information indicating whether the base station 30 is a base station that uses power generated by renewable energy.

[0035] The selector 12 selects, from among the plurality of candidate base stations, a candidate base station with a relatively small environmental load as a target base station for connection of the terminal based on the acquired "information on power used for communication" (step S12). For example, the selector 12 may select, from among the plurality of candidate base stations (i.e., base stations 30-1 to 30-3), a candidate base station that uses power generated by renewable energy as a target base station for connection.

[0036] As described above, according to the second embodiment, the selector 12 in the control device 10 selects, from among a plurality of candidate base stations, a candidate base station with a relatively small environmental load as a target base station for connection to the terminal 20, based on the "information on power used for communication" acquired by the acquirer 11. The "information on power used for communication" includes information indicating whether the candidate base station is a base station that uses power generated by renewable energy.

[0037] This configuration of the control device 10 enables the control device 10 to select a base station that uses power generated by renewable energy as a target base station for connection to the terminal 20. This enables the control device 10 to realize communication with a reduced environmental load.

[0038] <Modification of Second Embodiment> In the above, the detection unit 22 has been described as detecting candidate base stations based on the second broadcast signal, but the present disclosure is not limited to this. For example, the detection unit 22 may measure the position of the terminal 20 using a positioning system. In this case, the detection unit 22 may include a positioning system module (e.g., a Global Navigation Satellite System (GNSS) module). Then, the detection unit 22 may, for example, refer to position information of the base station 30 stored in a storage unit (not shown) included in the terminal 20 and identify the candidate base station based on the distance between the position of the terminal 20 and the position of the base station 30.

[0039] Third Embodiment The third embodiment relates to another example of "information about power used for communication." In the third embodiment, the "information about power used for communication" includes the distance between each candidate base station and a power plant that supplies power to each candidate base station. The basic configuration of the communication system of the third embodiment is the same as that of the communication system 1 of FIG. 2. The basic configuration of the base station of the third embodiment is the same as that of the base station 30 of FIG. 3. The basic configuration of the terminal of the third embodiment is the same as that of the terminal 20 of FIG. 4.

[0040] <Configuration Example of Base Station> In the base station 30 of the third embodiment, the control unit 32 transmits "information about the distance between the base station and the power plant that supplies power to the base station" of the base station 30 to the terminal 20 via the communication unit 31. For example, the control unit 32 may generate a broadcast signal including "information about the distance between the base station and the power plant that supplies power to the base station" of the base station 30 and information indicating the base station 30 (e.g., base station identification information, cell identification information). Then, the control unit 32 may transmit this broadcast signal via the communication unit 31. Hereinafter, this broadcast signal may be referred to as a "third broadcast signal." Furthermore, the distance between the power plant that supplies power to the base station and the base station may be referred to as a "first distance."

[0041] Here, the longer the distance between the power plant that supplies power to the base station and the base station, the greater the power loss that tends to occur during transmission between the power plant and the base station. Therefore, it is thought that the longer the distance between the power plant that supplies power to the base station and the base station, the greater the environmental impact of that base station.

[0042] In the base station 30 of the third embodiment, the control unit 32 may transmit the second broadcast signal to the terminal 20 via the communication unit 31, similar to the second embodiment.

[0043] <Example of terminal configuration> In the terminal 20 of the third embodiment, the extraction unit 23 extracts a "third broadcast signal" included in the received signal received from the communication unit 21. Then, the extraction unit 23 outputs the above-mentioned "information relating to the distance between the power plant that supplies power to the base station and the base station" and information indicating the base station 30 that is the transmission source, which are included in the "third broadcast signal," to the control device 10. Note that the processes of the detection unit 22 and the extraction unit 23 may be performed repeatedly periodically.

[0044] The acquisition unit 11 of the control device 10 receives information indicating the candidate base stations from the detection unit 22. The acquisition unit 11 also receives the above-mentioned "information regarding the distance between the power plant that supplies power to the base station and the base station" and information indicating the source base station 30 from the extraction unit 23. This allows the acquisition unit 11 to acquire "information regarding the distance between the power plant that supplies power to the base station and the base station" for each candidate base station. Note that when the processes of the detection unit 22 and the extraction unit 23 are repeatedly performed periodically, the acquisition unit 11 can repeatedly periodically acquire "information regarding the distance between the power plant that supplies power to the base station and the base station" for each candidate base station.

[0045] The selection unit 12 selects, from among the plurality of candidate base stations, a candidate base station with a relatively small environmental load as a "target base station for connection" for the terminal 20, based on the "information regarding the distance between the power plant that supplies power to the base station and the base station" acquired by the acquisition unit 11. The plurality of candidate base stations are base stations 30-1 to 30-3. For example, the selection unit 12 may select, from among the plurality of candidate base stations (i.e., base stations 30-1 to 30-3), the candidate base station with the shortest distance between the power plant that supplies power to the base station and the base station, as the target base station for connection.

[0046] As described above, according to the third embodiment, the selector 12 in the control device 10 selects, from among a plurality of candidate base stations, a candidate base station with a relatively small environmental load as a target base station for connection by the terminal 20, based on the "information on power used for communication" acquired by the acquirer 11. The "information on power used for communication" includes information on the distance between the base station 30 and the power plant that supplies power to the base station 30.

[0047] This configuration of the control device 10 allows the control device 10 to select the base station 30 that is the shortest distance from the power plant as the base station to which the terminal 20 is to be connected. This enables the control device 10 to achieve communication with reduced environmental impact.

[0048] <Variation of Third Embodiment> The detection unit 22 in the terminal 20 may calculate (estimate) the distance between the base station 30 and the terminal 20 based on the received signal strength. Then, the acquisition unit 11 of the control device 10 may further acquire the distance between the base station 30 and the terminal 40 (hereinafter, sometimes referred to as the "second distance") from the detection unit 22. Then, the selection unit 12 may select a target base station from the base stations 30-1 to 30-3 based on the first distance and the second distance for each base station 30. For example, the selection unit 12 calculates the sum of the first distance and the second distance for each base station 30. Then, the selection unit 12 selects the base station 30 with the smallest sum as the target base station.

[0049] <Fourth embodiment> The fourth embodiment relates to another example of "information on power used for communication." In the fourth embodiment, the "information on power used for communication" includes the amount of available power generated by renewable energy at each candidate base station. The basic configuration of the communication system of the fourth embodiment is the same as that of the communication system 1 of FIG. 2. The basic configuration of the base station of the fourth embodiment is the same as that of the base station 30 of FIG. 3. The basic configuration of the terminal of the fourth embodiment is the same as that of the terminal 20 of FIG. 4.

[0050] <Configuration Example of Base Station> In the base station 30 of the fourth embodiment, the control unit 32 transmits "information on the amount of available power generated by renewable energy" of the base station 30 to the terminal 20 via the communication unit 31. For example, the control unit 32 may generate a broadcast signal including the "information on the amount of available power generated by renewable energy" of the base station 30 and information indicating the base station 30 (e.g., base station identification information, cell identification information). Then, the control unit 32 may transmit this broadcast signal via the communication unit 31. Hereinafter, this broadcast signal may be referred to as a "fourth broadcast signal."

[0051] The "amount of available power generated by renewable energy" of the base station 30 is the amount of power generated by renewable energy out of the power supplied to the base station 30.

[0052] Here, the "information regarding the amount of available power generated by renewable energy" of the base station 30 may be information regarding the amount of power currently available, or information regarding the amount of power available after a predetermined time (i.e., in the future). The "information regarding the amount of available power generated by renewable energy" of the base station 30 may be obtained by the control unit 32 from the electric power company via the network interface unit 33.

[0053] In the base station 30 of the fourth embodiment, the control unit 32 may transmit the second broadcast signal to the terminal 20 via the communication unit 31, similar to the second embodiment.

[0054] <Example of terminal configuration> In the terminal 20 of the fourth embodiment, the extraction unit 23 extracts a "fourth broadcast signal" included in the received signal received from the communication unit 21. Then, the extraction unit 23 outputs the above-mentioned "information on the available amount of power generated by renewable energy" and information indicating the base station 30 that is the transmission source, which are included in the "fourth broadcast signal," to the control device 10. Note that the processes of the detection unit 22 and the extraction unit 23 may be performed repeatedly periodically.

[0055] The acquisition unit 11 of the control device 10 receives information indicating candidate base stations from the detection unit 22. The acquisition unit 11 also receives the above-mentioned "information on the amount of available power generated by renewable energy" and information indicating the source base station 30 from the extraction unit 23. This allows the acquisition unit 11 to acquire "information on the amount of available power generated by renewable energy" of each candidate base station. Note that when the processes of the detection unit 22 and the extraction unit 23 are repeatedly performed periodically, the acquisition unit 11 can repeatedly acquire "information on the amount of available power generated by renewable energy" of each candidate base station periodically.

[0056] The selector 12 selects, from among the plurality of candidate base stations, a candidate base station with a relatively small environmental load as a "target base station for connection" for the terminal 20, based on the "information on the available amount of power generated by renewable energy" acquired by the acquirer 11. The plurality of candidate base stations are base stations 30-1 to 30-3. For example, the selector 12 may select, from among the plurality of candidate base stations (i.e., base stations 30-1 to 30-3), the candidate base station with the largest available amount of power generated by renewable energy as the target base station for connection.

[0057] As described above, according to the fourth embodiment, the selector 12 in the control device 10 selects, from among a plurality of candidate base stations, a candidate base station with a relatively small environmental load as a target base station for connection to the terminal 20, based on the "information on power used for communication" acquired by the acquirer 11. The "information on power used for communication" includes information on the amount of available power generated by the base station 30 using renewable energy.

[0058] This configuration of the control device 10 enables the control device 10 to select the base station 30 with the largest available amount of power generated by renewable energy as the base station to which the terminal 20 is to connect. This enables the control device 10 to realize communication with a reduced environmental load.

[0059] Fifth Embodiment The fifth embodiment relates to another example of "information related to power used for communication." In the fifth embodiment, the "information related to power used for communication" is a "first index value" described later. Note that the basic configuration of a communication system in the fifth embodiment is the same as that of the communication system 1 in FIG. 2. Furthermore, the basic configuration of a base station in the fifth embodiment is the same as that of the base station 30 in FIG. 3. That is, the terminal 20 in FIG. 2 may be replaced with a terminal 40 described later.

[0060] <Configuration Example of Base Station> In the base station 30 of the fifth embodiment, the control unit 32 transmits the base station 30's "information regarding the currently available amount of power generated by renewable energy" to the terminal 20 via the communication unit 31. The base station 30's "information regarding the currently available amount of power generated by renewable energy" may hereinafter be simply referred to as "information regarding the currently available amount of power." The control unit 32 also transmits the base station 30's "information regarding the future available amount of power generated by renewable energy" to the terminal 20 via the communication unit 31. The base station 30's "information regarding the future available amount of power generated by renewable energy" may hereinafter be simply referred to as "information regarding the future available amount of power." For example, the control unit 32 may generate a broadcast signal including the base station 30's "information regarding the currently available amount of power," "information regarding the future available amount of power," and information identifying the base station 30 (e.g., base station identification information, cell identification information). The control unit 32 may then transmit this broadcast signal via the communication unit 31. Hereinafter, this broadcast signal may be referred to as a "fifth broadcast signal."

[0061] Here, the "information on the amount of power currently available from power generated by renewable energy" of the base station 30 is, for example, the amount of power generated by renewable energy that is available to the base station 30 at a certain timing (first timing) of the base station 30. Also, the "information on the amount of power generated by renewable energy that will be available in the future" of the base station 30 is, for example, the amount of power generated by renewable energy that is available to the base station 30 at multiple timings (multiple second timings) multiple predetermined times after the first timing. The multiple predetermined times are different from one another.

[0062] Furthermore, in the base station 30 of the fifth embodiment, the control unit 32 transmits "information related to the line speed (or line capacity)" of the base station 30 to the terminal 40 via the communication unit 31. For example, the control unit 32 may generate a broadcast signal including the "information related to the line speed (or line capacity)" of the base station 30 and information indicating the base station 30 (for example, base station identification information, cell identification information), and transmit this broadcast signal via the communication unit 31. Hereinafter, this broadcast signal may be referred to as a "sixth broadcast signal."

[0063] In the base station 30 of the fifth embodiment, the control unit 32 may transmit the second broadcast signal to the terminal 40 via the communication unit 31, similar to the second embodiment.

[0064] 6 is a block diagram showing another example of a terminal according to the present disclosure. In FIG. 6, a terminal 40 includes a communication unit 21, a detection unit 22, an extraction unit 23, and a control device 50.

[0065] In the terminal 40 of the fifth embodiment, the extraction unit 23 extracts a "fifth broadcast signal" included in the received signal received from the communication unit 21. Then, the extraction unit 23 outputs the above-mentioned "information related to the power used for communication" and information indicating the source base station 30, which are included in the "fifth broadcast signal," to the control device 50. Note that the processing of the extraction unit 23 may be performed periodically and repeatedly together with the detection unit 22.

[0066] In the terminal 40 of the fifth embodiment, the extraction unit 23 extracts a "sixth broadcast signal" included in the received signal received from the communication unit 21. Then, the extraction unit 23 outputs the above-mentioned "information related to line speed (or line capacity)" and information indicating the source base station 30, which are included in the "sixth broadcast signal," to the control device 50. Note that the processes of the detection unit 22 and the extraction unit 23 may be performed repeatedly periodically.

[0067] The control device 50 includes an acquisition unit 51 and a selection unit 52. The acquisition unit 51 includes an acquisition processing unit 51A, a scheduled time calculation unit 51B, and an index calculation unit 51C.

[0068] The acquisition processing unit 51A receives information indicating candidate base stations from the detection unit 22. The acquisition processing unit 51A receives the above-mentioned "information on currently available power amount," "information on future available power amount," and information indicating the source base station 30 from the extraction unit 23. As a result, the acquisition unit 51 can acquire the "information on currently available power amount" and the "information on future available power amount" of each candidate base station. Furthermore, the acquisition unit 51 receives the above-mentioned "information on line speed (or line capacity)" and information indicating the source base station 30 from the extraction unit 23. As a result, the acquisition unit 51 can acquire the "information on line speed (or line capacity)" of each candidate base station. Furthermore, the acquisition unit 51 acquires "information on desired data amount" of the terminal 40. The "desired data amount" is, for example, the amount of data (uplink data) that the terminal 40 currently plans to transmit.

[0069] The scheduled time calculation unit 51B calculates the scheduled communication time based on the line speed of each candidate base station acquired by the acquisition processing unit 51A and the desired data volume of the terminal 40. For example, the scheduled time calculation unit 51B calculates the scheduled communication time for each candidate base station by dividing the desired data volume by the line speed of each candidate base station.

[0070] The index calculation unit 51C calculates an index value (hereinafter, may be referred to as a "first index value") based on the planned communication time for each candidate base station calculated by the planned time calculation unit 51B and the "information on the currently available power amount" and the "information on the future available power amount" for each candidate base station acquired by the acquisition processing unit 51A. For example, the index calculation unit 51C may calculate the first index value by calculating the sum of the available power amount of renewable energy at timings within the planned communication time for each candidate base station.

[0071] The selection unit 52 selects a "target base station to connect" for the terminal 40 based on the first index value for each candidate base station calculated by the index calculation unit 51C. For example, the selection unit 52 selects the candidate base station corresponding to the largest first index value as the "target base station to connect" for the terminal 40.

[0072] As described above, according to the fifth embodiment, the selection unit 52 in the control device 50 selects, from among a plurality of candidate base stations, a candidate base station with a relatively small environmental load as the base station to which the terminal 40 is to connect, based on the first index value for each candidate base station acquired by the acquisition unit 51.

[0073] This configuration of the control device 50 enables the control device 50 to select the base station 30 with the largest available amount of power generated by renewable energy as the base station to which the terminal 40 is to connect. This enables the control device 50 to realize communication with a reduced environmental load.

[0074] Sixth Embodiment The sixth embodiment relates to another example of "information on power used for communication." In the sixth embodiment, the "information on power used for communication" includes an index value according to the expected power consumption for communication between the terminal and each candidate base station. The basic configuration of the communication system of the sixth embodiment is the same as that of the communication system 1 of FIG. 2. The basic configuration of the base station of the sixth embodiment is the same as that of the base station 30 of FIG. 3. That is, the terminal 20 in FIG. 2 may be replaced with a terminal 60, which will be described later.

[0075] <Configuration Example of Base Station> In the base station 30 of the sixth embodiment, the control unit 32 transmits "information related to the line speed (or line capacity)" of the base station 30 to the terminal 60 via the communication unit 31. For example, the control unit 32 may generate a broadcast signal including the "information related to the line speed (or line capacity)" of the base station 30 and information indicating the base station 30 (e.g., base station identification information, cell identification information), and transmit this broadcast signal via the communication unit 31. Hereinafter, this broadcast signal may be referred to as a "seventh broadcast signal."

[0076] In the base station 30 of the sixth embodiment, the control unit 32 may transmit the second broadcast signal to the terminal 40 via the communication unit 31, similar to the second embodiment.

[0077] 7 is a block diagram showing another example of a terminal according to the present disclosure. In FIG. 7, a terminal 60 includes a communication unit 21, a detection unit 22, an extraction unit 23, and a control device 70.

[0078] In the terminal 60 of the sixth embodiment, the detection unit 22 detects (measures) the received signal strength of the "second broadcast signal" included in the received signal. Then, the detection unit 22 may calculate (estimate) the distance between the base station 30 and the terminal 60 based on the received signal strength.

[0079] In the terminal 60 of the sixth embodiment, the extraction unit 23 extracts a "seventh broadcast signal" included in the received signal received from the communication unit 21. Then, the extraction unit 23 outputs the above-mentioned "information related to line speed (or line capacity)" and information indicating the source base station 30, which are included in the "seventh broadcast signal," to the control device 70. Note that the processing by the detection unit 22 and the extraction unit 23 may be performed repeatedly periodically.

[0080] The control device 70 includes an acquisition unit 71 and a selection unit 72. The acquisition unit 71 includes an acquisition processing unit 71A and an index calculation unit 71B.

[0081] The acquisition processing unit 71A receives information indicating candidate base stations from the detection unit 22. The acquisition processing unit 71A also receives the above-mentioned "information related to line speed (or line capacity)" and information indicating the source base station 30 from the extraction unit 23. This allows the acquisition processing unit 71A to acquire "information related to line speed (or line capacity)" of each candidate base station. The acquisition processing unit 71A also acquires "information related to the distance" between each candidate base station and the terminal 60, which is calculated by the detection unit 22. The acquisition processing unit 71A also acquires "information related to the desired data volume" of the terminal 60. The "desired data volume" is, for example, one or both of the data volume (uplink data volume) that the terminal 60 currently plans to transmit and the data volume (downlink data volume) that the terminal 60 currently plans to receive.

[0082] The index calculation unit 71B calculates an "index value according to the expected power consumption of the terminal 60 for communication between each candidate base station and the terminal 60" based on the "line speed" and "distance" for each candidate base station and the "desired data volume" of the terminal 60. Hereinafter, this expected power consumption may be referred to as a "first expected power consumption." This index value may also be referred to as a "second index value." That is, in the sixth embodiment, the acquisition unit 71 acquires the second index value for each candidate base station as "information related to the power used for communication between each candidate base station and the terminal 60."

[0083] Here, the faster the line speed, the shorter the communication time tends to be, and therefore the expected power consumption of terminal 60 tends to be smaller. Also, the shorter the distance between the candidate base station and terminal 60, the smaller the transmission power of terminal 60 tends to be, and therefore the expected power consumption of terminal 60 tends to be smaller. Also, the larger the "desired data volume," the longer the communication time tends to be, and therefore the expected power consumption of terminal 60 tends to be larger. Therefore, for example, index calculation unit 71B may calculate the "second index value" by multiplying the reciprocal of the line speed, the distance between the candidate base station and terminal 60, and the "desired data volume."

[0084] The selection unit 72 selects a "target base station to connect" for the terminal 60 based on the second index value for each candidate base station calculated by the index calculation unit 71B. For example, the selection unit 72 may select a candidate base station corresponding to the smallest second index value as the "target base station to connect" for the terminal 60.

[0085] As described above, according to the sixth embodiment, the selector 72 in the control device 70 selects, from among a plurality of candidate base stations, a candidate base station with a relatively small environmental load as a target base station for connection to the terminal 60, based on the "information on power used for communication" acquired by the acquirer 71. The "information on power used for communication" includes a second index value for each candidate base station (i.e., an index value according to the expected power consumption of the terminal 60 for communication between each candidate base station and the terminal 60).

[0086] This configuration of the control device 70 enables the control device 70 to select the base station 30 with the smallest expected power consumption of the terminal 60 as the base station to which the terminal 60 is to be connected. This enables the control device 70 to realize communication with a reduced environmental load.

[0087] Modification of the Sixth Embodiment In the above description, the distance between each candidate base station and the terminal is used to calculate the second index value, but the present disclosure is not limited to this. For example, the position (estimated position) of the terminal after a predetermined time (i.e., in the future) may be used to calculate the second index value.

[0088] 8 is a block diagram showing another example of a terminal according to the present disclosure. In FIG. 8, the terminal 80 includes a position estimation unit 81, a communication unit 21, a detection unit 22, an extraction unit 23, and a control device 70.

[0089] The detection unit 22 may include a positioning system module (e.g., a Global Navigation Satellite System (GNSS) module). The detection unit 22 may refer to the position information of the base station 30 stored in a storage unit (not shown) included in the terminal 20, and identify a candidate base station based on the distance between the position of the terminal 80 and the position of the base station 30.

[0090] The position estimation unit 81 estimates the position of the terminal 80 after a predetermined time (i.e., in the future) based on the position history of the terminal 80 detected by the detection unit 22. Then, the position estimation unit 81 calculates the distance (estimated distance) between the position of the terminal 80 after a predetermined time (i.e., in the future) and the position of the candidate base station based on the estimated position of the terminal 80 and the position of the candidate base station. Then, the position estimation unit 81 outputs the calculated estimated distance to the control device 70.

[0091] In the control device 70, the acquisition processing unit 71A receives information indicating candidate base stations from the detection unit 22. The acquisition processing unit 71A also receives the above-mentioned "information related to line speed (or line capacity)" and information indicating the source base station 30 from the extraction unit 23. This allows the acquisition processing unit 71A to acquire "information related to line speed (or line capacity)" of each candidate base station. The acquisition processing unit 71A also acquires "information related to the estimated distance" between each candidate base station and the terminal 80, which is calculated by the position estimation unit 81. The acquisition processing unit 71A also acquires "information related to the desired data volume" of the terminal 80. The "desired data volume" is, for example, one or both of the data volume (uplink data volume) that the terminal 80 currently plans to transmit and the data volume (downlink data volume) that the terminal 80 currently plans to receive.

[0092] The index calculation unit 71B calculates an "index value corresponding to the expected power consumption of terminal 60 for communication between each candidate base station and terminal 60" based on the "line speed" and "estimated distance" for each candidate base station, as well as the "desired data volume" of terminal 60.

[0093] Seventh Embodiment The seventh embodiment relates to another example of "information about power used for communication." In the seventh embodiment, the "information about power used for communication" includes an index value according to the expected power consumption of a candidate base station for communication between a terminal and the candidate base station. The basic configuration of the communication system of the seventh embodiment is the same as that of the communication system 1 in FIG. 2. That is, the base station 30 in FIG. 2 may be replaced with a base station 90, which will be described later. Furthermore, the terminal 20 in FIG. 2 may be replaced with a terminal 100, which will be described later.

[0094] <Configuration Example of Base Station> Fig. 9 is a block diagram showing another example of a base station according to the present disclosure. In Fig. 9, a base station 90 includes a communication unit 91, a control unit 92, and a network interface unit 33. The control unit 92 includes an acquisition unit 92A, an index calculation unit 92B, and a transmission control unit 92C.

[0095] The acquisition unit 92A acquires, via the communication unit 91, "information relating to the distance between the base station 90 and the terminal 100" and "information relating to the desired data volume" of the terminal 100, which are transmitted from the terminal 100 during temporary connection. The "desired data volume" is, for example, one or both of the volume of data that the terminal 100 currently plans to transmit (uplink data volume) and the volume of data that the terminal 100 currently plans to receive (downlink data volume). In addition, the acquisition unit 92A acquires "information relating to the line speed (or line capacity)" of the base station 90.

[0096] The index calculation unit 92B calculates an "index value according to the expected power consumption of the base station 90 for communication between the base station 90 and the terminal 100" based on the "line speed" of the base station 90, the "distance between the base station 90 and the terminal 100," and the "desired data volume" of the terminal 100. Hereinafter, this expected power consumption may be referred to as the "second expected power consumption." This index value may also be referred to as the "third index value."

[0097] Here, the faster the line speed, the shorter the communication time tends to be, and therefore the expected power consumption of the base station 90 tends to be smaller. Also, the shorter the distance between the base station 90 and the terminal 100, the smaller the transmission power of the base station 90 tends to be, and therefore the expected power consumption of the base station 90 tends to be smaller. Also, the larger the "desired data volume," the longer the communication time tends to be, and therefore the expected power consumption of the base station 90 tends to be larger. Therefore, for example, the index calculation unit 92B may calculate the "third index value" by multiplying the reciprocal of the line speed, the distance between the base station 90 and the terminal 100, and the "desired data volume."

[0098] The transmission control unit 92C transmits a signal including the third index value calculated by the index calculation unit 92B and information indicating the base station 90 (e.g., base station identification information, cell identification information) to the terminal 100 via the communication unit 91.

[0099] In the base station 90 of the seventh embodiment, the control unit 92 may transmit the second broadcast signal to the terminal 90 via the communication unit 21, similar to the control unit 32 of the second embodiment.

[0100] 10 is a block diagram showing another example of a terminal according to the present disclosure. In FIG. 10, the terminal 100 includes a communication unit 101, a detection unit 102, an extraction unit 103, and a control device 110.

[0101] The detection unit 102 receives a received signal from the communication unit 101. Then, the detection unit 102 detects (measures) the received signal strength of the "second broadcast signal" included in the received signal. The detection unit 102 then calculates (estimates) the distance between the base station 90 and the terminal 100 based on the received signal strength. The detection unit 102 also detects information indicating the base station 90 that is the source of the second broadcast signal based on the "second broadcast signal" included in the received signal. Here, the base station 90 that is the source of the second broadcast signal corresponding to a received signal strength equal to or greater than the "first threshold" corresponds to the candidate base station. Here, it is assumed that each of the base stations 90-1 to 90-3 is a candidate base station.

[0102] Then, the detection unit 102 outputs information indicating the candidate base stations to the control device 110 .

[0103] The communication unit 101 tentatively connects to the base stations 90-1 to 90-3 in sequence. Then, the communication unit 101 transmits to each base station 90 information relating to the distance between the base station 90 and the terminal 100 calculated by the detection unit 102, and information relating to the "desired data volume" of the terminal 100. The communication unit 101 then receives a signal including the above-mentioned third index value transmitted from each base station 90.

[0104] The extraction unit 103 receives a received signal from the communication unit 101. Then, the extraction unit 103 outputs the third index value included in the received signal and information indicating the base station 90 to the control device 110. Note that the processing by the detection unit 102 and the extraction unit 103 may be performed repeatedly periodically.

[0105] The control device 110 includes an acquisition unit 111 and a selection unit 112 .

[0106] The acquisition unit 111 receives information indicating the candidate base station from the detection unit 102. The acquisition unit 111 also receives information indicating the third index value and the source base station 90 from the extraction unit 103. This allows the acquisition unit 111 to acquire the third index value of each candidate base station. Note that when the processes of the detection unit 102 and the extraction unit 103 are repeatedly performed periodically, the acquisition unit 111 can repeatedly acquire the third index value of each candidate base station periodically.

[0107] The selection unit 112 selects, from among the plurality of candidate base stations (i.e., base stations 90-1 to 90-3), a candidate base station with a relatively small environmental load as the "target base station for connection" for the terminal 100, based on the third index value of each candidate base station acquired by the acquisition unit 111. For example, the selection unit 112 may select the candidate base station corresponding to the smallest third index value as the "target base station for connection" for the terminal 100.

[0108] As described above, according to the seventh embodiment, the selection unit 112 in the control device 110 selects, from among a plurality of candidate base stations, a candidate base station with a relatively small environmental load as a target base station for connection by the terminal 100, based on the "information on power used for communication" acquired by the acquisition unit 111. The "information on power used for communication" includes a third index value for each candidate base station (i.e., an index value according to the expected power consumption of each candidate base station for communication between each candidate base station and the terminal 100).

[0109] This configuration of the control device 110 enables the control device 110 to select the base station 90 with the smallest expected power consumption as the base station to which the terminal 100 is to connect. This enables the control device 110 to realize communication with a reduced environmental load.

[0110] <Other Embodiments> <1> In the second to sixth embodiments, the control devices 10, 50, and 70 acquire information via the first and third to seventh broadcast signals, but the present disclosure is not limited to this. For example, the control devices 10, 50, and 70 of the second to sixth embodiments may acquire information from a candidate base station through a tentative connection, as in the seventh embodiment.

[0111] <2> Each piece of information used as the "information on power used for communication" described in the first to seventh embodiments may correspond to one mode. That is, the control device may use information corresponding to a mode specified by a user as the "information on power used for communication." For example, when a mode using "information indicating whether a base station uses power generated by renewable energy" as the "information on power used for communication" is selected, the control device may select a candidate base station that uses power generated by renewable energy as the connection target base station. Furthermore, as a method of prompting the user to select a mode, for example, selection buttons for a "base station selection mode with high greenness," a "base station selection mode with low waste," and a "base station selection mode with high surplus ratio" may be displayed on a display unit (not shown) of the terminal. The "base station selection mode with high greenness" corresponds to, for example, the second embodiment described above. The "base station selection mode with low waste" corresponds to, for example, the third embodiment described above. The "base station selection mode with high surplus ratio" corresponds to, for example, the fourth or fifth embodiment described above.

[0112] <3> Figure 11 is a diagram showing an example of the hardware configuration of a control device. In Figure 11, the control device 200 has a processor 201 and a memory 202. The processor 201 may be, for example, a microprocessor, a micro processing unit (MPU), or a central processing unit (CPU). The processor 201 may include multiple processors. The memory 202 is configured by a combination of volatile memory and non-volatile memory. The memory 202 may include storage located away from the processor 201. In this case, the processor 201 may access the memory 202 via an I (Input) / O (Output) interface (not shown).

[0113] The control devices 10, 50, 70, and 110 of the first to seventh embodiments may each have the hardware configuration shown in FIG. 10 . The acquisition units 11, 51, 71, and 111 and the selection units 12, 52, 72, and 112 of the control devices 10, 50, 70, and 110 of the first to seventh embodiments may be implemented by the processor 201 reading and executing a program stored in the memory 202. The program can be stored using various types of non-transitory computer-readable media and supplied to the control devices 10, 50, 70, and 110. Examples of non-transitory computer-readable media include magnetic recording media (e.g., flexible disks, magnetic tapes, and hard disk drives) and magneto-optical recording media (e.g., magneto-optical disks). Further examples of non-transitory computer-readable media include CD-ROMs (Read Only Memory), CD-Rs, and CD-R / Ws. Further examples of non-transitory computer-readable media include semiconductor memories. The semiconductor memory may include, for example, a mask ROM, a programmable ROM (PROM), an erasable PROM (EPROM), a flash ROM, and a random access memory (RAM). The program may also be provided to the control device 10, 50, 70, or 110 by various types of transitory computer-readable media. Examples of transitory computer-readable media include electrical signals, optical signals, and electromagnetic waves. The transitory computer-readable media may provide the program to the control device 10, 50, 70, or 110 via a wired communication path, such as an electrical wire or optical fiber, or via a wireless communication path.

[0114] <4> Figure 12 is a diagram showing an example of the hardware configuration of a terminal. In Figure 12, the terminal 300 has a processor 301, a memory 302, and a communication circuit 303. The processor 301 may be, for example, a microprocessor, a micro processing unit (MPU), or a central processing unit (CPU). The processor 301 may include multiple processors. The memory 302 is configured by a combination of volatile memory and non-volatile memory. The memory 302 may include storage located away from the processor 301. In this case, the processor 301 may access the memory 302 via an I (Input) / O (Output) interface (not shown).

[0115] The terminals 20, 40, 60, 80, and 100 of the second to seventh embodiments may each have the hardware configuration shown in FIG. 12 . The detection units 22 and 102, extraction units 23 and 103, position estimation unit 81, acquisition units 11, 51, 71, and 111, and selection units 12, 52, 72, and 112 of the terminals 20, 40, 60, 80, and 100 of the second to seventh embodiments may be realized by the processor 301 reading and executing programs stored in the memory 302. The communication units 21 and 101 may be realized by the communication circuit 303. The programs may be stored using various types of non-transitory computer-readable media and supplied to the terminals 20, 40, 60, 80, and 100. Examples of non-transitory computer-readable media include magnetic recording media (e.g., flexible disks, magnetic tapes, and hard disk drives) and magneto-optical recording media (e.g., magneto-optical disks). Further examples of non-transitory computer-readable media include CD-ROMs (Read Only Memory), CD-Rs, and CD-R / Ws. Further examples of non-transitory computer-readable media include semiconductor memories. Semiconductor memories include, for example, mask ROMs, programmable ROMs (PROMs), erasable PROMs (EPROMs), flash ROMs, and random access memories (RAMs). The program may also be provided to the terminals 20, 40, 60, 80, and 100 via various types of transitory computer-readable media. Examples of transitory computer-readable media include electrical signals, optical signals, and electromagnetic waves. The transitory computer-readable media may provide the program to the terminals 20, 40, 60, 80, and 100 via wired communication paths such as electrical wires and optical fibers, or wireless communication paths.

[0116] <5> Figure 13 is a diagram showing an example of the hardware configuration of a base station. In Figure 13, a base station 400 has a processor 401, a memory 402, a communication circuit 403, and a network interface 404. The processor 401 may be, for example, a microprocessor, an MPU (Micro Processing Unit), or a CPU (Central Processing Unit). The processor 401 may include multiple processors. The memory 402 is configured by a combination of volatile memory and non-volatile memory. The memory 402 may include storage located away from the processor 401. In this case, the processor 401 may access the memory 402 via an I (Input) / O (Output) interface (not shown).

[0117] The base stations 30 and 90 of the second to seventh embodiments may each have the hardware configuration shown in FIG. 13 . The control units 32 and 92 of the base stations 30 and 90 of the second to seventh embodiments may be implemented by a processor 401 reading and executing a program stored in a memory 402. The storage unit 34 may be implemented by the memory 402. The communication units 31 and 91 may be implemented by a communication circuit 403. The network interface unit 33 may be implemented by a network interface 404. The program can be stored and supplied to the base stations 30 and 90 using various types of non-transitory computer-readable media. Examples of non-transitory computer-readable media include magnetic recording media (e.g., flexible disks, magnetic tapes, hard disk drives) and magneto-optical recording media (e.g., magneto-optical disks). Further examples of non-transitory computer-readable media include CD-ROMs (Read Only Memory), CD-Rs, and CD-R / Ws. Further examples of non-transitory computer-readable media include semiconductor memories. The semiconductor memory includes, for example, a mask ROM, a programmable ROM (PROM), an erasable PROM (EPROM), a flash ROM, and a random access memory (RAM). The program may also be provided to the base station 30, 90 by various types of transitory computer-readable media. Examples of transitory computer-readable media include electrical signals, optical signals, and electromagnetic waves. The transitory computer-readable media may provide the program to the base station 30, 90 via a wired communication path such as an electrical wire or optical fiber, or via a wireless communication path.

[0118] Although the present disclosure has been described above with reference to the embodiments, the present disclosure is not limited to the above-described embodiments. Various modifications that can be understood by those skilled in the art can be made to the configuration and details of the present disclosure within the scope of the present disclosure. Furthermore, each embodiment can be combined with other embodiments as appropriate.

[0119] Each drawing is merely an example for describing one or more embodiments. Each drawing may not relate to only one particular embodiment, but may also relate to one or more other embodiments. As will be understood by those skilled in the art, various features or steps described with reference to any one drawing can be combined with features or steps shown in one or more other drawings to create, for example, an embodiment not explicitly shown or described. Not all features or steps shown in any one drawing are necessary to describe an exemplary embodiment, and some features or steps may be omitted. The order of steps described in any drawing may be changed as appropriate.

[0120] Some or all of the above embodiments can be described as, but are not limited to, the following supplementary notes: (Supplementary Note 1) A control device comprising: an acquisition unit that acquires information regarding power used for communication between a terminal and each of a plurality of candidate wireless stations for connection by the terminal; and a selection unit that selects, from among the plurality of candidate wireless stations, a candidate wireless station with a relatively small environmental load as a target wireless station for connection by the terminal, based on the acquired information regarding power. (Supplementary Note 2) The control device according to Supplementary Note 1, wherein the information regarding power used for communication between each candidate wireless station and the terminal includes information indicating whether each candidate wireless station uses power generated by renewable energy, and the selection unit selects, as the target wireless station for connection, a candidate wireless station that uses power generated by renewable energy. (Supplementary Note 3) The control device according to Supplementary Note 1, wherein the information on power used for communication between each candidate radio station and the terminal includes an index value corresponding to a first expected amount of power consumption for communication between the terminal and each candidate radio station, and the selection unit selects, as the target radio station, a candidate radio station corresponding to communication having the smallest index value corresponding to the first expected amount of power consumption. (Supplementary Note 4) The control device according to Supplementary Note 1, wherein the information on power used for communication between each candidate radio station and the terminal includes an index value corresponding to a second expected amount of power consumption for the communication of each candidate radio station, and the selection unit selects, as the target radio station, a candidate radio station corresponding to the communication having the smallest index value corresponding to the second expected amount of power consumption. (Supplementary Note 5) The control device according to Supplementary Note 1, wherein the information on power used for communication between each candidate radio station and the terminal includes an available amount of power generated by each candidate radio station using renewable energy, and the selection unit selects, as the target radio station, a candidate radio station corresponding to communication having the largest available amount of power.(Supplementary Note 6) The control device according to Supplementary Note 1, wherein the acquisition unit comprises: an acquisition processing unit that acquires information on the amount of power currently available and the amount of power that will be available in the future regarding power generated by renewable energy of each candidate wireless station, information on the line speed of each candidate wireless station, and information on the amount of data planned to be communicated by the terminal; a planned time calculation unit that calculates a planned communication time based on the line speed of each candidate wireless station and the amount of data planned to be communicated by the terminal; and an index value calculation unit that calculates, for each candidate wireless station, a sum of the amount of power available from renewable energy at a timing within the planned communication time based on the planned communication time and the information on the amount of power currently available and the amount of power that will be available in the future regarding power generated by renewable energy of each candidate wireless station; and the selection unit selects a candidate wireless station corresponding to the largest index value as the connection target wireless station. (Supplementary Note 7) The control device according to Supplementary Note 1, wherein the information on power used for communication between each candidate radio station and the terminal includes a first distance between each candidate radio station and a power plant that supplies power to each candidate radio station, and the selection unit selects the connection target radio station based on the first distance for each candidate radio station. (Supplementary Note 8) The control device according to Supplementary Note 7, wherein the acquisition unit further acquires information on a second distance between the terminal and each candidate radio station, and the selection unit selects the connection target radio station based on the first distance and the second distance for each candidate radio station. (Supplementary Note 9) The control device according to Supplementary Note 8, wherein the selection unit calculates a sum of the first distance and the second distance for each candidate radio station, and selects the candidate radio station with the smallest sum as the connection target radio station. (Supplementary Note 10) A terminal including the control device according to any one of Supplements 1 to 9. (Supplementary Note 11) A control method executed by a control device, comprising: acquiring information regarding power used for communication between a terminal and each of a plurality of candidate wireless stations to which the terminal is to connect; and selecting, based on the acquired information regarding power, from among the plurality of candidate wireless stations, a candidate wireless station with a relatively small environmental load as a target wireless station for connection of the terminal.(Supplementary Note 12) The control method according to Supplementary Note 11, wherein the information on power used for communication between each candidate wireless station and the terminal includes information indicating whether each candidate wireless station is a wireless station that uses power generated by renewable energy, and wherein the selecting includes selecting, as the connection target wireless station, a candidate wireless station that uses power generated by renewable energy. (Supplementary Note 13) The control method according to Supplementary Note 11, wherein the information on power used for communication between each candidate wireless station and the terminal includes an index value corresponding to a first expected amount of power consumption for communication between the terminal and each candidate wireless station, and wherein the selecting includes selecting, as the connection target wireless station, a candidate wireless station that corresponds to communication with the terminal and has the smallest index value corresponding to the first expected amount of power consumption. (Supplementary Note 14) The control method according to Supplementary Note 11, wherein the information on power used for communication between each candidate wireless station and the terminal includes an index value corresponding to a second expected amount of power consumption for the communication of each candidate wireless station, and the selecting includes selecting, as the target wireless station, a candidate wireless station corresponding to the communication having the smallest index value corresponding to the second expected amount of power consumption. (Supplementary Note 15) The control method according to Supplementary Note 11, wherein the information on power used for communication between each candidate wireless station and the terminal includes an available amount of power generated by renewable energy of each candidate wireless station, and the selecting includes selecting, as the target wireless station, a candidate wireless station corresponding to the communication having the largest available amount of power.(Supplementary Note 16) The control method according to Supplementary Note 11, wherein the acquiring includes acquiring information on the amount of power currently available and the amount of power that will be available in the future for power generated by renewable energy of each candidate wireless station, information on the line speed of each candidate wireless station, and information on the amount of data planned to be communicated by the terminal; calculating a planned communication time based on the line speed of each candidate wireless station and the amount of data planned to be communicated by the terminal; and calculating, for each candidate wireless station, a sum of the amount of power available from renewable energy at a timing within the planned communication time based on the planned communication time and the information on the amount of power currently available and the amount of power that will be available in the future for power generated by renewable energy of each candidate wireless station; and wherein the selecting includes selecting the candidate wireless station corresponding to the largest index value as the wireless station to be connected. (Supplementary Note 17) The control method according to Supplementary Note 11, wherein the information on power used for communication between each candidate radio station and the terminal includes a first distance between each candidate radio station and a power plant that supplies power to each candidate radio station, and wherein the selecting includes selecting the connection target radio station based on the first distance for each candidate radio station. (Supplementary Note 18) The control method according to Supplementary Note 17, further including obtaining information on a second distance between the terminal and each candidate radio station, and wherein the selecting includes selecting the connection target radio station based on the first distance and the second distance for each candidate radio station. (Supplementary Note 19) The control method according to Supplementary Note 18, wherein the selecting includes calculating a sum of the first distance and the second distance for each candidate radio station, and selecting the candidate radio station having the smallest sum as the connection target radio station. (Supplementary Note 20) A program that causes a control device to execute a process including: acquiring information about the power used for communication between a terminal and each of a plurality of candidate wireless stations to which the terminal is to connect; and selecting, based on the acquired information about the power, a candidate wireless station that has a relatively small environmental load from among the plurality of candidate wireless stations, as a wireless station to which the terminal is to connect.(Supplementary Note 21) The program according to Supplementary Note 20, wherein the information on power used for communication between each candidate wireless station and the terminal includes information indicating whether each candidate wireless station uses power generated by renewable energy, and wherein the selecting includes selecting, as the connection target wireless station, a candidate wireless station that uses power generated by renewable energy. (Supplementary Note 22) The program according to Supplementary Note 20, wherein the information on power used for communication between each candidate wireless station and the terminal includes an index value corresponding to a first expected amount of power consumption for communication between the terminal and each candidate wireless station, and wherein the selecting includes selecting, as the connection target wireless station, a candidate wireless station corresponding to communication having the smallest index value corresponding to the first expected amount of power consumption. (Supplementary Note 23) The program according to Supplementary Note 20, wherein the information on power used for communication between each candidate wireless station and the terminal includes an index value corresponding to a second expected amount of power consumption for the communication of each candidate wireless station, and wherein the selecting includes selecting, as the connection target wireless station, a candidate wireless station corresponding to the communication having the smallest index value corresponding to the second expected amount of power consumption. (Supplementary Note 24) The program according to Supplementary Note 20, wherein the information on the power used for communication between each candidate wireless station and the terminal includes an available amount of power generated by renewable energy at each candidate wireless station, and the selecting includes selecting, as the target wireless station, a candidate wireless station corresponding to communication with the largest amount of available power.(Supplementary Note 25) The program according to Supplementary Note 20, wherein the acquiring includes acquiring information on the amount of power currently available and the amount of power that will be available in the future for power generated by renewable energy of each candidate wireless station, information on the line speed of each candidate wireless station, and information on the amount of data planned to be communicated by the terminal; calculating a planned communication time based on the line speed of each candidate wireless station and the amount of data planned to be communicated by the terminal; and calculating, for each candidate wireless station, a sum of the amount of power available from renewable energy at a timing within the planned communication time based on the planned communication time and the information on the amount of power currently available and the amount of power that will be available in the future for power generated by renewable energy of each candidate wireless station; and wherein the selecting includes selecting a candidate wireless station corresponding to the largest index value as the connection target wireless station. (Supplementary Note 26) The program according to Supplementary Note 20, wherein the information on power used for communication between each candidate wireless station and the terminal includes a first distance between each candidate wireless station and a power plant that supplies power to each candidate wireless station, and the selecting includes selecting the connection target wireless station based on the first distance for each candidate wireless station. (Supplementary Note 27) The program according to Supplementary Note 26, wherein the processing further includes acquiring information on a second distance between the terminal and each candidate wireless station, and the selecting includes selecting the connection target wireless station based on the first distance and the second distance for each candidate wireless station. (Supplementary Note 28) The program according to Supplementary Note 27, wherein the selecting includes calculating a sum of the first distance and the second distance for each candidate wireless station, and selecting the candidate wireless station having the smallest sum as the connection target wireless station.

[0121] This application claims priority based on Japanese Patent Application No. 2023-144583, filed September 6, 2023, the disclosure of which is incorporated herein by reference in its entirety.

[0122] REFERENCE SIGNS LIST 1 communication system 10 control device 11 acquisition unit 12 selection unit 20 terminal 21 communication unit 22 detection unit 23 extraction unit 30 base station (radio station) 31 communication unit 32 control unit 33 network interface unit 34 storage unit 40 terminal 50 control device 51 acquisition unit 51A acquisition processing unit 51B estimated time calculation unit 51C index calculation unit 52 selection unit 60 terminal 70 control device 71 acquisition unit 71A acquisition processing unit 71B index calculation unit 72 selection unit 80 terminal 81 position estimation unit 91 communication unit 92 control unit 92A acquisition unit 92B index calculation unit 92C transmission control unit 100 terminal 101 communication unit 102 detection unit 103 extraction unit 110 control device 111 acquisition unit 112 selection section

Claims

1. A control device comprising: an acquisition unit that acquires information regarding the power used for communication between a terminal and each of a plurality of candidate wireless stations to which the terminal is to connect; and a selection unit that selects, based on the acquired information regarding power, from among the plurality of candidate wireless stations, a candidate wireless station with a relatively small environmental load as a wireless station to which the terminal is to connect.

2. The control device as described in claim 1, wherein the information regarding the power used for communication between each candidate wireless station and the terminal includes information indicating whether each candidate wireless station is a wireless station that uses power generated by renewable energy, and the selection unit selects a candidate wireless station that uses power generated by renewable energy as the wireless station to be connected.

3. The control device as described in claim 1, wherein information regarding the power used for communication between each candidate wireless station and the terminal includes an index value corresponding to a first expected power consumption for communication between the terminal and each candidate wireless station, and the selection unit selects the candidate wireless station corresponding to communication with the smallest index value corresponding to the first expected power consumption as the wireless station to be connected.

4. The control device as described in claim 1, wherein the information regarding the power used for communication between each candidate wireless station and the terminal includes an index value corresponding to a second expected power consumption for the communication of each candidate wireless station, and the selection unit selects the candidate wireless station corresponding to the communication having the smallest index value corresponding to the second expected power consumption as the wireless station to be connected.

5. The control device according to claim 1, wherein the information regarding the power used for communication between each candidate wireless station and the terminal includes an available amount of power generated by renewable energy at each candidate wireless station, and the selection unit selects the candidate wireless station corresponding to the communication with the largest amount of available power as the wireless station to be connected.

6. The control device according to claim 1, wherein the acquisition unit comprises: an acquisition processing unit that acquires information regarding the currently available amount of power and the future available amount of power for power generated by renewable energy of each candidate wireless station, information regarding the line speed of each candidate wireless station, and information regarding the planned communication data amount of the terminal; a planned time calculation unit that calculates a planned communication time based on the line speed of each candidate wireless station and the planned communication data amount of the terminal; and an index value calculation unit that calculates, for each candidate wireless station, a sum of the available amount of power for renewable energy at a timing within the planned communication time based on the planned communication time and information regarding the currently available amount of power and the future available amount of power for power generated by renewable energy of each candidate wireless station, as an index value corresponding to the amount of power generated by renewable energy; and wherein the selection unit selects the candidate wireless station corresponding to the largest index value as the connection target wireless station.

7. The control device according to claim 1, wherein the information regarding the power used for communication between each candidate radio station and the terminal includes a first distance between each candidate radio station and a power plant that supplies power to each candidate radio station, and the selection unit selects the connection target radio station based on the first distance for each candidate radio station.

8. The control device according to claim 7, wherein the acquisition unit further acquires information regarding a second distance between the terminal and each candidate wireless station, and the selection unit selects the connection target wireless station based on the first distance and the second distance for each candidate wireless station.

9. The control device according to claim 8, wherein the selection unit calculates a sum of the first distance and the second distance for each candidate wireless station, and selects the candidate wireless station with the smallest sum as the connection target wireless station.

10. A control method executed by a control device, comprising: acquiring information regarding the power used for communication between each of a plurality of candidate wireless stations to which a terminal is to connect and the terminal; and selecting, based on the acquired information regarding power, from among the plurality of candidate wireless stations, a candidate wireless station with a relatively small environmental load as a wireless station to which the terminal is to connect.

11. The control method according to claim 10, wherein the information regarding the power used for communication between each candidate wireless station and the terminal includes information indicating whether each candidate wireless station is a wireless station that uses power generated by renewable energy, and the selecting includes selecting a candidate wireless station that uses power generated by renewable energy as the wireless station to be connected.

12. The control method described in claim 10, wherein the information regarding the power used for communication between each candidate wireless station and the terminal includes an index value corresponding to a first expected power consumption for communication between the terminal and each candidate wireless station, and the selecting includes selecting, as the wireless station to be connected, a candidate wireless station corresponding to communication having the smallest index value corresponding to the first expected power consumption.

13. The control method described in claim 10, wherein the information regarding the power used for communication between each candidate wireless station and the terminal includes an index value corresponding to a second expected power consumption for the communication of each candidate wireless station, and the selecting includes selecting, as the wireless station to be connected, a candidate wireless station corresponding to the communication having the smallest index value corresponding to the second expected power consumption.

14. The control method according to claim 10, wherein the information regarding the power used for communication between each candidate wireless station and the terminal includes an available amount of power generated by renewable energy in each candidate wireless station, and the selecting step includes selecting a candidate wireless station corresponding to communication having the largest amount of available power as the wireless station to be connected.

15. The control method according to claim 10, wherein the acquiring step includes acquiring information on the currently available amount of power and the future available amount of power generated by renewable energy of each candidate wireless station, information on the line speed of each candidate wireless station, and information on the planned amount of data communication of the terminal, calculating a planned communication time based on the line speed of each candidate wireless station and the planned amount of data communication of the terminal, and calculating, for each candidate wireless station, the sum of the available amount of power of renewable energy at a timing within the planned communication time based on the planned communication time and information on the currently available amount of power generated by renewable energy of each candidate wireless station and the future available amount of power, and wherein the selecting step includes selecting a candidate wireless station corresponding to the largest index value as the wireless station to be connected.

16. The control method according to claim 10, wherein the information regarding the power used for communication between each candidate radio station and the terminal includes a first distance between each candidate radio station and a power plant that supplies power to each candidate radio station, and the selecting step includes selecting the connection target radio station based on the first distance for each candidate radio station.

17. The control method according to claim 16, further comprising: acquiring information regarding a second distance between the terminal and each candidate wireless station; and wherein the selecting includes selecting the connection target wireless station based on the first distance and the second distance for each candidate wireless station.

18. The control method according to claim 17, wherein the selecting step includes calculating a sum of the first distance and the second distance for each candidate wireless station, and selecting the candidate wireless station having the smallest sum as the connection target wireless station.

19. A program that causes a control device to execute a process including: acquiring information regarding the power used for communication between each of a plurality of candidate wireless stations to which a terminal can connect and the terminal; and selecting, based on the acquired information regarding power, from among the plurality of candidate wireless stations, a candidate wireless station with a relatively small environmental impact as the wireless station to which the terminal can connect.

20. The program described in claim 19, wherein the information regarding the power used for communication between each candidate wireless station and the terminal includes information indicating whether each candidate wireless station is a wireless station that uses power generated by renewable energy, and the selecting includes selecting a candidate wireless station that uses power generated by renewable energy as the wireless station to be connected.

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