JP2021193775A - Control device, control method, and program for improving utilization efficiency of massive mimo - Google Patents

Abstract

To effectively utilize massive MIMO in cellular communication systems.SOLUTION: A control device acquires information on a situation of each of a plurality of terminal devices, determines based on the information on the situation whether to connect each of the terminal devices to a network using massive MIMO (Multi Input Multi Output) or to the network without using massive MIMO, and performs control to connect each of the terminal devices to the network based on the determination.SELECTED DRAWING: Figure 4

Description

The present invention relates to a control technique for applying Massive MIMO to a terminal device.

In cellular communication systems, the application of Massive MIMO (Multi Input Multi Output), which improves frequency utilization efficiency by actively using spatial resources using a large number of antennas, is being studied.

The present invention provides an effective utilization technique of Massive MIMO in a cellular communication system.

The control device according to one aspect of the present invention has an acquisition means for acquiring information on the situation in each of the plurality of terminal devices, and Massive MIMO (Multi Input Multi) for each of the plurality of terminal devices based on the information on the situation. To determine whether to connect to the network using Output) or to connect to the network without Massive MIMO, and to connect each of the plurality of terminal devices to the network based on the determination. It has a control means for controlling the above.

According to the present invention, Massive MIMO can be effectively utilized in a cellular communication system.

It is a figure which shows the configuration example of a wireless communication system. It is a figure which shows the hardware configuration example of a control device. It is a figure which shows the functional composition example of a control device. It is a figure explaining the example of the flow of processing executed by a control device.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. It should be noted that the following embodiments do not limit the invention according to the claims, and not all combinations of features described in the embodiments are essential to the invention. Two or more of the plurality of features described in the embodiments may be arbitrarily combined. In addition, the same or similar configuration will be given the same reference number, and duplicated explanations will be omitted.

(System configuration)
FIG. 1 shows a configuration example of a wireless communication system according to the present embodiment. This wireless communication system is a wireless communication system to which Massive MIMO can be applied, and in order to realize Massive MIMO, a base station device 101 for Massive MIMO including a large number of antenna elements is arranged. By forming a highly directional beam by a large number of antenna elements included in the base station device 101, high-speed, large-capacity / high-quality wireless communication is provided for each of one or more terminal devices 103. It will be possible. The base station device 101 controls a large number of antennas included in the base station device 101 so as to form a beam toward each of the terminal devices 103 of the communication partner and transmit / receive signals.

The wireless communication system may also include a base station device 102 that communicates using a normal antenna in a conventional cellular communication system. The base station apparatus 101 is arranged within the range of the macro cell developed by the base station apparatus 102, for example, and is configured to be able to configure a cell smaller than the macro cell (the range is variable depending on the shape of the beam). As long as the cell configured by the base station apparatus 101 and the cell configured by the base station apparatus 102 can provide the wireless communication service within a common geographical range, for example, the cell configured by the base station apparatus 101 is preferable. It may cover a wider area than the cell configured by the base station apparatus 102, or the cell configured by the base station apparatus 101 and the cell configured by the base station apparatus 102 may be configured to partially overlap each other. good. That is, each cell is configured so that the non-Massive MIMO communication system and the Massive MIMO communication system coexist in a common area to provide wireless communication services to the terminal device. The base station device 101 may be a device capable of performing processing such as amplification and filtering at radio frequency (RF), baseband processing, and the like, as a general base station device has, but only has an antenna function. It may be an antenna device having the above, and signal processing such as RF and baseband processing may be executed by an external device such as an internal device of the base station device 102. In one example, the base station device 101 can be treated as a base station device constituting a cell having a narrower coverage area than a macro cell. The terminal device can be connected to a predetermined network via any of such a base station device 101 and a base station device 102. In other words, the terminal can be connected to a given network in either Massive MIMO or non-Massive MIMO form. In the example of FIG. 1, the terminal device 104 is connected to the base station device 102.

Here, the base station apparatus 101 and the base station apparatus 102 collect information from the terminal apparatus and communicate the information with each other to bring the terminal apparatus into a predetermined network in either Massive MIMO or non-Massive MIMO format. You may control whether to connect. Further, when the control device is included in the base station device 101 or the base station device 102, the control device controls using only the information of the terminal device that communicates with the base station device 101 or the base station device 102 including the own device. May be done. Further, a control device existing separately from the base station device 101 and the base station device 102 may perform control such as determining a terminal device to be connected to the base station device 101 and the base station device 102. That is, a control device may exist as a higher-level device of the base station device 101 and the base station device 102.

In the example of FIG. 1, only one non-Massive MIMO base station device and only two base station devices 101 for Massive MIMO are shown, but this is for the sake of simplicity. There can be many such devices in general. Further, although only five terminal devices are shown, naturally, there may be a larger number of terminal devices.

Massive MIMO increases communication capacity by sharing the same frequency resources with multiple terminal devices existing at different positions by increasing antenna gain in multiple specific directions using a large number of antennas. It is a technology. On the other hand, Massive MIMO may not be able to obtain sufficient communication capacity when the estimation accuracy of the radio channel between each terminal device and each antenna is insufficient. Therefore, for example, by selecting a terminal device having high channel estimation accuracy and providing a communication service by Massive MIMO, Massive MIMO can be used more effectively. That is, by appropriately setting which terminal device to communicate with Massive MIMO and which terminal device to communicate with non-Massive MIMO among a large number of terminal devices, the frequency of the entire system It is possible to improve the utilization efficiency. Therefore, in the present embodiment, whether each of the plurality of terminal devices is connected to a predetermined network using Massive MIMO or to a predetermined network without using Massive MIMO, for example, based on the channel estimation accuracy. A control device (not shown in FIG. 1) for determining the above is prepared. The control device may be a device that controls Massive MIMO as described above, or may be a device that controls both Massive MIMO and non-Massive MIMO. Further, the control device may be included in the base station device 102. The channel estimation accuracy is an example, and the control device acquires information on various situations of the terminal device, and based on the acquired information, whether or not each terminal device is connected to a predetermined network by Massive MIMO. It is possible to determine whether or not, and based on the determination, execute control for connecting each of the terminal devices to a predetermined network. If there is a terminal device that does not support communication with Massive MIMO, the control device determines that the terminal device is connected to a predetermined network without using Massive MIMO. That is, the control device decides whether or not to use Massive MIMO for communication between the terminal device and a predetermined network, considering the situation only for the terminal device that supports communication with Massive MIMO. do.

Here, the information regarding the status of the terminal device is, for example, information indicating either the electric field strength of the uplink and the electric field strength of the downlink for each of the terminal devices, or the electric field strength at both the uplink and the downlink. Can include. The electric field strength of the uplink corresponds to the reception strength when the radio wave transmitted from each terminal device is received by the antenna for Massive MIMO. Further, the electric field strength of the downlink corresponds to the reception strength when the radio waves transmitted from each of the antennas for Massive MIMO are received by each terminal device. In this case, the control device determines that the terminal device having a high electric field strength for the link to be evaluated (at least one of the uplink and the downlink) is preferentially connected to a predetermined network by Massive MIMO. When the electric field strength is high, there is a high probability that the channel estimation value can be made highly accurate. Therefore, by deciding to preferentially connect the terminal device with high electric field strength to a predetermined network by Massive MIMO. , Massive MIMO utilization efficiency can be improved.

Further, the information regarding the status of the terminal device may include information indicating the amount of downlink transmission target data for each of the terminal devices. Then, the control device may decide to preferentially connect the terminal device having a large amount of transmission target data indicated by the information to a predetermined network by Massive MIMO. Further, the information regarding the status of the terminal device may include information indicating the amount of uplink transmission target data for each of the terminal devices. Then, the control device may decide to preferentially connect a terminal device having a small amount of transmission target data indicated by the information to a predetermined network by Massive MIMO. Further, the information regarding the status of the terminal device may include information regarding the communication executed on the downlink for each of the terminal devices. In this case, the control device may decide to preferentially connect the terminal device that continuously executes a large amount of data communication on the downlink to a predetermined network by Massive MIMO. Further, the information regarding the status of the terminal device may include information regarding the communication being executed on the uplink for each of the terminal devices. In this case, the control device decides to preferentially connect the terminal device that continuously executes communication with a small amount of data on the uplink to a predetermined network by Massive MIMO.

Massive MIMO, for example, in a Time Division Duplex (TDD) system, is such that the network side receives an uplink signal based on the duality of the uplink radio channel and the downlink radio channel. It can be configured to estimate the radio channel of the link. At this time, in TDD, the ratio of the time slot for uplink communication and the time slot for downlink communication is applied according to the ratio of the amount of data transmitted on the uplink and the amount of data transmitted on the downlink. Possible to be configured. At this time, in general, the amount of time slots for downlink communication tends to be larger than the amount of time slots for uplink communication. For this reason, if at least one of the terminal devices having a large amount of uplink communication or a small downlink communication volume communicates with Massive MIMO, the amount of radio resources cannot be fully utilized. Can be assumed. Therefore, in the control device of the present embodiment, the terminal device, which is assumed to have at least one of a large amount of downlink communication and a small amount of uplink communication, communicates with Massive MIMO. Can be decided. The control device is based on, for example, the amount of data to be transmitted / received to / from each terminal device (for example, the amount of downlink / uplink data buffer) and the service used by each terminal device. , May be configured to be able to identify the amount of uplink / downlink communication to be performed. Then, based on this identified information, the control device can determine whether or not to connect each terminal device to a predetermined network by Massive MIMO as described above.

Further, the information regarding the status of the terminal device may include information indicating the correlation of the channel with the other terminal device for each of the terminal devices. The channel correlation information is calculated, for example, based on the channel information between each terminal device and the base station device transmitted by each terminal device to the base station device. In this case, the control device connects one of the two terminal devices whose channel correlation exceeds a predetermined value to a predetermined network using Massive MIMO, and another of the two terminal devices. It can be determined that one terminal device is connected to a given network without using Massive MIMO. When Massive MIMO is applied to both of two or more terminals with high channel correlation, it becomes difficult to spatially separate the signals of those terminals, and the communication quality of both may deteriorate. Because. The control device may decide not to apply Massive MIMO to both of these two terminal devices.

Further, the information regarding the status of the terminal device may include information on the position of each of the terminal devices. In this case, the control device can determine whether or not to connect the terminal device to a predetermined network by Massive MIMO based on each position of the terminal device. For example, the control device connects one terminal device of two terminal devices located close to each other to a predetermined network by Massive MIMO, and connects another terminal device of the two terminal devices. , It can be decided to connect to a predetermined network without using Massive MIMO. The control device may decide not to apply Massive MIMO to both of these two terminal devices. This is because when the positions of the terminal devices are close to each other, it is assumed that it will be difficult to spatially separate the signals for those terminal devices by the antenna. In addition, as one aspect of the position information, the information indicating the correlation of the above-mentioned channels may be used. Further, the position information may be specified by, for example, the positioning result by the GPS (Global Positioning System) device of each terminal device, or may be specified by the direction of each terminal device from each antenna used in Massive MIMO. good. The control device can, for example, acquire the position information measured in each terminal device and specify the direction of each terminal device as seen from each antenna from the position information. Then, the control device controls two terminal devices having the same direction as seen from the antenna or included in a predetermined narrow range so that only one of them is connected to a predetermined network by Massive MIMO. It should be noted that it may be determined that both of the two terminal devices having the same direction as seen from the antenna or included in a predetermined narrow range are connected to a predetermined network without using Massive MIMO.

In addition, the control device may predefine a plurality of geographical areas having low correlation with each other. For example, a geographical relationship in which the channel correlation between the two terminal devices is lower than a predetermined level can be specified in advance, and a plurality of geographical areas can be preset according to the specific result. In this case, the controller can consider the channel correlation to be low for two terminal devices, each belonging to a different geographic area. Then, when a plurality of terminal devices exist in one geographical area, the control device determines that at most one terminal device among the plurality of terminal devices is connected to a predetermined network by Massive MIMO. Can be done. The controller may also obtain information for each of the plurality of geographic areas that identifies the geographic area to which a large amount of data is transmitted or received. Then, the control device may decide to preferentially connect the terminal device belonging to the geographical area to which a large amount of data is transmitted / received to a predetermined network by Massive MIMO.

When deciding whether or not to connect to a predetermined network by Massive MIMO based on the geographical position of the terminal device, the control device is connected to a predetermined network by Massive MIMO or a predetermined network. It is possible to extract a combination of two terminal devices from the terminal devices to be connected to the above, specify the channel correlation and positional relationship for all the combinations, and execute the above determination.

Further, the information regarding the status of the terminal device may include information indicating whether or not each of the terminal devices is moving. For example, the control device may monitor changes in the position information of the terminal device to identify whether or not each of the terminal devices is moving. Further, the control device may specify whether or not the terminal device is moving by acquiring the detection result of the sensor (for example, a gyro sensor, an acceleration sensor, etc.) in each of the terminal devices. Further, the control device may specify whether or not the terminal device is moving based on the fluctuation of the radio quality in each of the terminal devices. Then, the control device may decide to preferentially connect a terminal device that is not moving or a terminal device that has a small amount of movement per unit time to a predetermined network by Massive MIMO.

Further, the information regarding the status of the terminal device may include information specifying the communication service used by each of the terminal devices. In this case, the control device may decide to preferentially connect the terminal device using the predetermined communication service to the predetermined network by using Massive MIMO. This makes it possible to connect a terminal device running a service to which Massive MIMO is preferentially applied to a predetermined network by Massive MIMO.

It should be noted that the various information described above can be used in combination. For example, with each of the above indicators as an element, information including a plurality of elements can be used as information regarding the status of the terminal device. In this case, it is possible to determine whether or not to connect each terminal device to a predetermined network by Massive MIMO according to the value obtained by multiplying the value corresponding to each of these plurality of elements by a weighting coefficient and adding them. For example, if the higher the priority of connecting to a predetermined network with Massive MIMO, the higher the value is used as the value corresponding to each element, and a positive weighting factor is applied, the value as a result of the weighted addition is used. It can be determined that the larger the terminal device is, the more preferentially Massive MIMO should be used to connect to a predetermined network. The weighting factor may be set according to the environment. For example, if a railroad track is within the service area of Massive MIMO, the weighting factor may be adjusted so that the value corresponding to the mobility factor has a strong influence on the result. Also, for example, when an area such as an event venue where users are expected to be crowded is included in the Massive MIMO service area, the value corresponding to the positional relationship element such as channel correlation has a strong influence on the result. , The weighting factor can be adjusted.

It should be noted that the above determination can be repeatedly executed for each of the terminal devices connected to a predetermined network and communicating with each other. Thereby, for example, the control device can execute the handover so that the terminal device connected to the predetermined network without using Massive MIMO is connected to the predetermined network by Massive MIMO. Similarly, the control device can, for example, execute a handover so that a terminal device connected to a predetermined network by Massive MIMO is connected to a predetermined network without using Massive MIMO.

(Device configuration)
Subsequently, a hardware configuration example of the control device that executes the above-mentioned processing will be described with reference to FIG. In one example, the control device includes a processor 201, a ROM 202, a RAM 203, a storage device 204, and a communication circuit 205. The processor 201 is a computer including one or more processing circuits such as a general-purpose CPU (central processing unit) and an ASIC (integrated circuit for a specific application), and is stored in a ROM 202 or a storage device 204. By reading and executing the existing program, the entire processing of the control unit and each of the above-mentioned processing are executed. The ROM 202 is a read-only memory that stores information such as programs and various parameters related to processing executed by the control device. The RAM 203 is a random access memory that functions as a workspace when the processor 201 executes a program and stores temporary information. The storage device 204 is configured by, for example, a detachable external storage device or the like. The communication circuit 205 is composed of, for example, a circuit for wired communication or wireless communication. The communication circuit 205 includes, for example, a baseband circuit and an RF circuit for communication with a terminal device via a Massive MIMO antenna. Further, the communication circuit 205 may include a circuit for performing (wired or wireless) communication with a network node such as another control device or a base station device that does not use Massive MIMO. Although one communication circuit 205 is shown in FIG. 2, the control device may have a plurality of communication circuits.

FIG. 3 shows an example of the functional configuration of the control device. The control device includes, for example, an information acquisition unit 301, a Massive MIMO connection terminal determination unit 302, and a connection control unit 303. It should be noted that these functional units can be realized, for example, by the processor 201 executing a program stored in the ROM 202 or the storage device 204. However, this is just an example, and dedicated hardware that realizes these functional parts may be prepared.

The information acquisition unit 301 acquires information about the situation in each of one or more terminal devices to be connected to a predetermined network such as a network of a telecommunications carrier. In addition, the information acquisition unit 301 may acquire information on the situation only for the terminal device that supports the communication by Massive MIMO. That is, since a terminal device that does not support communication with Massive MIMO is not connected to a predetermined network by Massive MIMO, the information acquisition unit 301 does not acquire information on the situation of such a terminal device. May be good. Information about the situation can include one or more elements as in each of the above examples. Since each element is as described above, it is not repeated here. The information acquisition unit 301 can generate and acquire information on whether or not each terminal device is moving based on the position information of each terminal device (for example, information on the positioning result by the terminal device). Further, based on the communication service being executed by each terminal device, it is possible to specify whether or not continuous communication is performed on the uplink and the downlink, and the amount of data at that time. As described above, the information acquisition unit 301 may not only acquire information from the outside but also internally acquire another information element based on the possessed information.

Based on the information about the situation of each of the terminal devices acquired by the information acquisition unit 301, the Massive MIMO connection terminal determination unit 302 connects each of the terminal devices to a predetermined network by Massive MIMO, or Massive MIMO. Decide whether to connect to the given network without using it. Since what kind of terminal device is preferentially connected to the network by Massive MIMO is as described above, the description here will be omitted. When the information regarding the status of the terminal device includes a plurality of elements, the Massive MIMO connection terminal determination unit 302 sets each terminal based on the value obtained by weighting and adding the values corresponding to each element as described above. It is possible to decide whether or not to connect the device to a predetermined network by Massive MIMO. At this time, the Massive MIMO connection terminal determination unit 302 is based on, for example, whether there is an event in which users are crowded, or whether a railroad track or a high-traffic road is included in the Massive MIMO service area. , The weighting factor used for weighted addition can be adjusted. Information on whether or not an event exists and information on railroad tracks and roads can be acquired by, for example, the information acquisition unit 301.

The connection control unit 303 connects each of the terminal devices to a predetermined network based on the determination by the Massive MIMO connection terminal determination unit 302. That is, the connection control unit 303 can perform processing such as transmission of a message for connecting to Massive MIMO to the terminal device determined to be connected to a predetermined network by Massive MIMO. Similarly, the connection control unit 303 performs processing such as transmission of a message for connecting to a base station device that does not use Massive MIMO to a terminal device that is determined to be connected to a predetermined network without using Massive MIMO. You can do it.

The information acquisition unit 301 periodically acquires information even while each terminal device is communicating, and the Massive MIMO connection terminal determination unit 302 determines whether or not Massive MIMO is applied to each terminal device based on the information. Can be continuously determined. Then, based on the determination, the connection control unit 303 hands over a terminal device connected to a predetermined network by, for example, Massive MIMO to a base station device that does not use Massive MIMO, and a base that does not use Massive MIMO. It is possible to execute control for handing over the terminal device connected to the station device to the Massive MIMO side. That is, the terminal device can execute a state transition between a state in which Massive MIMO is used and a state in which Massive MIMO is not used, depending on the situation, based on the control of the connection control unit 303.

(Process flow)
Subsequently, an example of the flow of processing executed by the control device will be outlined with reference to FIG. Since the detailed processing in each processing step is as described above, the description here will be omitted. First, the control device acquires information on the status of the terminal device for each of the terminal devices to be connected to (and connected to) a predetermined network such as a network of a telecommunications carrier (S401). Then, the control device determines whether or not to connect each terminal device to the network by Massive MIMO based on the acquired information (S402), and executes the connection control of each terminal device based on the decision. (S403).

In this way, it is determined whether or not to connect to the network by Massive MIMO according to the situation of each terminal device, and the terminal device to be connected to Massive MIMO is selected. Then, for example, a terminal device that deteriorates the communication efficiency of Massive MIMO by applying Massive MIMO is connected to a base station device or the like that does not use Massive MIMO. As a result, Massive MIMO can be effectively utilized in the cellular communication system, and the efficiency of the entire wireless communication system can be improved.

The present invention is not limited to the above embodiments, and various modifications and modifications can be made without departing from the spirit and scope of the present invention. Therefore, in order to publicize the scope of the present invention, the following claims are attached.

Claims (19)

An acquisition means for acquiring information on the situation in each of a plurality of terminal devices,
A decision to determine whether each of the plurality of terminals is connected to the network using Massive MIMO (Multi Input Multi Output) or to the network without Massive MIMO based on the information regarding the situation. Means and
Based on the determination, a control means for controlling to connect each of the plurality of terminal devices to the network, and a control means.
A control device characterized by having. The information regarding the situation includes information indicating at least one of an uplink electric field strength and a downlink electric field strength for each of the plurality of terminal devices.
The determination means makes the determination so that the terminal device having a high electric field strength indicated by the information regarding the situation is preferentially connected to the network by using Massive MIMO.
The control device according to claim 1. The information regarding the situation includes information indicating the amount of downlink transmission target data for each of the plurality of terminal devices.
The determination means makes the determination so that the terminal device having a large amount of data to be transmitted indicated by the information regarding the situation is preferentially connected to the network by using Massive MIMO.
The control device according to claim 1 or 2. The information regarding the situation includes information indicating the amount of uplink transmission target data for each of the plurality of terminal devices.
The determination means makes the determination so that the terminal device having a small amount of data to be transmitted indicated by the information regarding the situation is preferentially connected to the network by using Massive MIMO.
The control device according to any one of claims 1 to 3. The information regarding the situation includes information regarding the communication performed on the downlink for each of the plurality of terminal devices.
The determination means preferentially connects a terminal device to the network using Massive MIMO, which is indicated by information about the situation that the downlink is continuously performing a large amount of data communication. To make the above decision,
The control device according to any one of claims 1 to 4. The information regarding the situation includes information regarding the communication performed on the uplink for each of the plurality of terminal devices.
The determination means preferentially connects the terminal device to the network using Massive MIMO, which is indicated by the information about the situation that the uplink is continuously performing a small amount of data communication. , Make the above decision,
The control device according to any one of claims 1 to 5. The information regarding the situation includes information indicating the correlation of the channel with the other terminal device for each of the plurality of terminal devices.
The determination means connects one of the two terminal devices whose channel correlation exceeds a predetermined value to the network using Massive MIMO, and another one of the two terminal devices. The determination is made to connect the terminal device to the network without using Massive MIMO.
The control device according to any one of claims 1 to 6, wherein the control device is characterized by the above. The information regarding the situation includes information on the position of each of the plurality of terminal devices.
The determination means makes the determination based on the respective positions of the plurality of terminal devices.
The control device according to any one of claims 1 to 6, wherein the control device is characterized by the above. The determining means preferentially determines a terminal device to be connected to the network using Massive MIMO based on the direction from the antenna in each Massive MIMO of the plurality of terminal devices.
The control device according to claim 8. The acquisition means further acquires information on a plurality of predefined geographic areas that are less correlated with each other.
The determining means preferentially determines a terminal device to be connected to the network using Massive MIMO based on which of the plurality of geographical areas each position of the plurality of terminal devices belongs to. ,
The control device according to claim 8. The acquisition means further acquires, for each of the plurality of geographical areas, information that identifies the geographical area to which a large amount of data is transmitted / received.
The determination means makes the determination so that a terminal device belonging to a geographical area to which a large amount of data is transmitted / received is preferentially connected to the network using Massive MIMO.
The control device according to claim 10. The information regarding the situation includes information indicating whether or not each of the plurality of terminal devices is moving.
The determination means makes the determination so that the non-moving terminal device is preferentially connected to the network using Massive MIMO.
The control device according to any one of claims 1 to 11. The acquisition means provides information indicating whether or not each of the plurality of terminal devices is moving based on a change in the position of each of the plurality of terminal devices or a detection result in a sensor in each of the plurality of terminal devices. The control device according to claim 12, wherein the control device is obtained. 12. The acquisition means is characterized in that it acquires information indicating whether or not each of the plurality of terminal devices is moving based on the fluctuation of the radio quality in each of the plurality of terminal devices. The control device described in. The information regarding the situation includes information specifying the communication service used by each of the plurality of terminal devices.
The determination means makes the determination so that the terminal device using the predetermined communication service is preferentially connected to the network by using Massive MIMO.
The control device according to any one of claims 1 to 14. When the information regarding the situation includes a plurality of elements, the determination means makes the determination based on the result of multiplying the values corresponding to the plurality of elements by a weighting coefficient and adding them.
The control device according to any one of claims 1 to 15. When the terminal device connected to the network using Massive MIMO is determined by the determination means to connect to the network without using Massive MIMO, the control means hands over the terminal device. The control device according to any one of claims 1 to 16. A control method performed by a control device,
Acquiring information about the situation in each of multiple terminal devices,
Based on the information regarding the situation, it is determined whether each of the plurality of terminal devices is connected to the network using Massive MIMO (Multi Input Multi Output) or connected to the network without Massive MIMO. When,
Based on the determination, control for connecting each of the plurality of terminal devices to the network is performed.
A control method characterized by including. To the computer installed in the control device
Get information about the situation in each of multiple terminal devices,
Based on the information about the situation, each of the plurality of terminal devices is made to decide whether to connect to the network using Massive MIMO (Multi Input Multi Output) or to connect to the network without using Massive MIMO.
Based on the determination, control for connecting each of the plurality of terminal devices to the network is performed.
Program for.

Images