JP6697588B1 - Communication terminal, program, method and system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a communication terminal, a program, a method and a system connectable to an appropriate wireless base station. Kind Code: A1 A communication terminal that is present in a cell formed by a radio base station and relays communication between a radio base station and a user terminal, and cell identification information that satisfies the condition of high load is registered. A registration information storage unit that stores the registered information, a registration determination unit that determines whether or not the serving cell of the communication terminal is registered in the registration information, and a registration determination unit that determines that the registration determination unit is registered. , A strength determination unit that determines whether or not the strength of radio waves received from the serving cell of the communication terminal is lower than a predetermined serving cell threshold value, and if the strength determination unit determines that the strength is low, it is adjacent to the communication terminal. A connection control unit that controls a communication terminal to be present in an adjacent cell that is not registered in the registration information among the cells. [Selection diagram] Figure 2

Description

  The present invention relates to a communication terminal, program, method and system.

There has been known a wireless communication system in which a wireless base station connected to a communication terminal is determined by a controller of the wireless base station (see, for example, Patent Document 1).
[Prior Art Document]
[Patent Document]
[Patent Document 1] Japanese Unexamined Patent Publication No. 2011-035763

  It is desirable to provide a technology that enables a communication terminal to connect to an appropriate wireless base station.

  According to the first aspect of the present invention, there is provided a communication terminal that is present in a cell formed by a wireless base station and relays communication between the wireless base station and the user terminal. The communication terminal may include a registration information storage unit that stores registration information in which cell identification information that satisfies the condition that the load is high is registered. The communication terminal may include a registration determination unit that determines whether or not the serving cell of the communication terminal is registered in the registration information. The communication terminal, when it is determined that the registration determination unit is registered, the strength determination unit that determines whether or not the radio reception intensity from the serving cell of the communication terminal is lower than a predetermined serving cell threshold value. May be provided. The communication terminal includes a connection control unit that controls the communication terminal so that the communication terminal is located in an adjacent cell that is not registered in the registration information among the adjacent cells of the communication terminal when it is determined to be low by the strength determination unit. Good.

  The registration information may include a serving cell threshold value associated with the identification information of the cell, the strength determination unit, when it is determined that is registered by the registration determination unit, of the communication terminal It may be determined whether or not the radio wave reception intensity from the serving cell is lower than the serving cell threshold value corresponding to the serving cell. The communication terminal, when it is determined to be low by the strength determination unit, an adjacent cell strength acquisition unit that acquires the radio reception strength from the adjacent cell of the communication terminal, and the radio wave reception acquired by the adjacent cell strength acquisition unit. Based on the strength, may be provided with a connection availability determination unit that determines the availability of connection between the communication terminal and the adjacent cell, the connection control unit, the adjacent cell determined to be connectable by the connection availability determination unit The communication terminal may be controlled so that the communication terminal is in the area.

  The registration information may include an adjacent cell absolute threshold value associated with the identification information of the cell, the connection availability determination unit, the radio reception intensity acquired by the adjacent cell strength acquisition unit, in the serving cell The connection may be determined to be possible when the value is higher than the corresponding absolute value of the adjacent cell. The registration information is associated with the identification information of the cell, may include the same frequency adjacent cell absolute threshold and different frequency adjacent cell absolute threshold, the connection availability determination unit, the serving cell and the adjacent cell Is a cell of the same frequency, the radio reception intensity acquired by the adjacent cell strength acquisition unit, if it is higher than the same frequency adjacent cell absolute threshold corresponding to the serving cell, it is determined that connection is possible, If the cell and the adjacent cell is a cell of different frequency, the radio reception strength acquired by the adjacent cell strength acquisition unit is connectable when the different frequency adjacent cell absolute threshold corresponding to the serving cell is higher than You may judge. The registration information may include an adjacent cell relative threshold value associated with the identification information of the cell, the connection availability determination unit, the radio reception intensity acquired by the adjacent cell strength acquisition unit, the communication terminal of the communication terminal The connection may be determined to be possible when the value is higher than the value obtained by subtracting the adjacent cell relative threshold value corresponding to the serving cell from the radio wave reception intensity from the serving cell. The registration information may include an adjacent cell absolute threshold and an adjacent cell relative threshold associated with the identification information of the cell, the connection availability determination unit, the radio reception intensity acquired by the adjacent cell strength acquisition unit is the Higher than the adjacent cell absolute threshold corresponding to the serving cell, and the radio reception intensity acquired by the adjacent cell strength acquisition unit, from the radio reception intensity from the serving cell of the communication terminal, to the serving cell When the value is higher than the value obtained by subtracting the corresponding adjacent cell relative threshold value, it may be determined that connection is possible.

  The communication terminal, when it is determined to be low by the strength determination unit, after the communication between the communication terminal and the radio base station forming the serving cell is completed, a state of not communicating is predetermined. A non-communication detection unit that detects that it has continued for a predetermined time, and, in accordance with the detection by the non-communication detection unit, may include an adjacent cell strength measurement unit that measures the radio reception strength from the adjacent cell of the communication terminal. The adjacent cell strength acquisition unit may acquire the radio wave reception strength measured by the adjacent cell strength measurement unit. The adjacent cell strength measurement unit, in response to the detection by the non-communication detection unit, after disconnecting the communication connection between the wireless base station forming the serving cell and the communication terminal, adjacent to the communication terminal The strength of reception of radio waves from the cell may be measured. The adjacent cell strength measurement unit, according to the detection by the non-communication detection unit, after the connection state with the radio base station forming the serving cell transitions to an idle state, the adjacent cell of the communication terminal You may measure the radio wave reception strength from.

  The communication terminal may include a connection determination cell list storage unit that stores a connection determination cell list in which the availability of connection between the communication terminal and the adjacent cell is determined by the connection availability determination unit, The connection control unit refers to the connection determination cell list when the mobility function of switching the connection destination of the communication terminal to the adjacent cell occurs, and the connection destination cell is the connection determination cell list. If it is registered in, the communication terminal and the adjacent cell to be switched to may be controlled not to establish a communication connection. The communication terminal requests the registration information according to a preset schedule from a registration information management server that manages the registration information, and receives the registration information from the registration information management server to receive the registration information. A registration information updating unit for updating may be provided.

  According to the second aspect of the present invention, there is provided a program for causing a computer to function as the communication terminal.

  According to a third aspect of the present invention there is provided a method performed by a communication terminal residing in a cell formed by a radio base station and relaying communication between the radio base station and a user terminal. The method may include a registration determination step of determining whether or not the serving cell of the communication terminal is registered in the registration information in which the identification information of the cell that satisfies the condition that the load is high is registered. The method, when it is determined that it is registered in the registration determination step, a strength determination step of determining whether the radio reception strength from the serving cell of the communication terminal is lower than a predetermined serving cell threshold. You may be prepared. The method may include a connection control step of controlling the communication terminal so that the communication terminal is located in an adjacent cell that is not registered in the registration information among the adjacent cells of the communication terminal when it is determined to be low in the strength determination step. ..

  According to a fourth aspect of the present invention, there is provided a system including the communication terminal and a registration information management server that manages the registration information. The registration information management server, the load information acquisition unit that acquires the load information indicating the load of each of the plurality of cells, and the registration information that generates the registration information based on the load information acquired by the load information acquisition unit A generation unit and a registration information transmission unit that transmits the registration information to the communication terminal may be provided.

  Note that the above summary of the invention does not enumerate all necessary features of the present invention. Further, a sub-combination of these feature groups can also be an invention.

1 schematically shows an example of a system 10 according to the present embodiment. 1 schematically shows an example of the functional configuration of the communication terminal 100. 1 schematically shows an example of a functional configuration of the registration information management server 400. It is an explanatory view for explaining processing in which communication terminal 100 updates a connection judging cell list. 1 schematically shows an example of the flow of processing by the communication terminal 100. 1 schematically shows an example of the flow of processing by the communication terminal 100. An example of processing by the communication terminal 100 is schematically shown. An example of the flow of processing by the registration information management server 400 is schematically shown. 1 schematically shows an example of a hardware configuration of a computer 1000 that functions as a communication terminal 100.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. Moreover, not all combinations of the features described in the embodiments are essential to the solving means of the invention.

  FIG. 1 schematically shows an example of a system 10 according to this embodiment. The system 10 includes a communication terminal 100 and a registration information management server 400.

  The communication terminal 100 stays in a cell formed by the wireless base station 200 and relays communication between the wireless base station 200 and the user terminal 500. The communication terminal 100 is, for example, a Wi-Fi (registered trademark) router.

  The communication terminal 100, the wireless base station 200, and the user terminal 500 are wireless communication systems such as a 3G (3rd Generation) communication system, an LTE (Long Term Evolution) communication system, a 5G (5th Generation) communication system, and a Wi-Fi communication system. May comply with. Here, a case where the communication terminal 100, the radio base station 200, and the user terminal 500 conform to the LTE communication system will be mainly described as an example.

  The radio base station 200 may form only one cell or may form a plurality of cells. The radio base station 200 forms, for example, a plurality of cells having different frequencies. The radio base station 200 forms, for example, a plurality of cells that overlap or have different areas to be covered.

  The user terminal 500 may be any terminal as long as it can communicate with the communication terminal 100. The user terminal 500 is, for example, a mobile phone such as a smartphone. The user terminal 500 may be a tablet terminal, a PC (Personal Computer), or the like. The user terminal 500 may be a so-called IoT (Internet of Thing) device. The user terminal 500 may include anything corresponding to so-called IoE (Internet of Everything).

  When the communication terminal 100 is located in a cell, the communication terminal 100 is located in a cell formed by a specific wireless base station 200 and is in a state of establishing a connection with the wireless base station 200 or the wireless base station 200. It means that the connection is established in the past and reconnection is possible. The serving cell is a cell formed by the wireless base station 200 that has established a connection with the communication terminal 100 or the wireless base station 200 that has previously established a connection with the communication terminal 100 and is reconnectable. Called etc. The adjacent cell is a cell formed by the wireless base station 200 adjacent to the wireless base station 200 forming the existing cell, and is called a neighbor cell or the like.

  In a conventional wireless communication system, a cell in which a communication terminal is located broadcasts (BroadCast) from a network-side device such as MME (Mobility Management Entity), BBU (Base Band Unit), eNodeB (LTE), or gNodeB (5G). )It had been. Such a device on the network side receives the radio wave reception intensity from the serving cell and the radio wave reception intensity from the adjacent cell, which are measured by the communication terminal, from the communication terminal, and based on the radio wave reception intensity, the communication terminal is detected. I had decided the cell to make the area. In such a conventional mechanism, a communication terminal may be located in a cell of a radio base station with a heavy load. The load here is, for example, a processing load and a communication load. When a communication terminal is connected to a radio base station with a high load, communication between the communication terminal and the radio base station is not performed smoothly, and the user experience of the user terminal that communicates via the communication terminal deteriorates. There were cases.

  To prevent a communication terminal from increasing to a cell formed by a heavily loaded wireless base station (generally called the best server; the cell with the most radio level being the most stable), manage the heavily loaded wireless base station. (Registered in the management server) and there were cases where the sales of communication terminals were restricted within the cell best server. However, even if such a regulation is performed, a communication terminal sold outside the regulated area may actually be connected to a high-load base station, which may deteriorate the user experience. .. For example, depending on the installation height of the wireless base station, even if the visibility is good and the antenna tilt is shallow, the radio waves may fly farther than expected, and communication terminals located outside the regulated area may In some cases, the radio wave of the radio base station is received and the connection is established with the radio base station. In addition, a communication terminal sold outside the restricted area may be brought into the restricted area.

  In the system 10 according to the present embodiment, the communication terminal 100 has a function of suppressing the communication terminal 100 from connecting to the high load base station. By providing the communication terminal 100 with such a function, for example, it is possible to suppress the connection to the high-load base station without significantly changing the configuration on the network side or without changing the configuration at all.

  The communication terminal 100 stores, for example, a blacklist in which cell identification information that satisfies the condition that the load is high is registered. The blacklist may be an example of registration information. The condition that the load is high may be that the communication load of the cell is higher than a predetermined threshold value. Further, the condition that the load is high may be that the processing load of the radio base station 200 forming the cell is higher than a predetermined threshold value.

  For example, when the communication terminal 100 is located in the cell of the wireless base station 200, the communication terminal 100 determines whether the serving cell is registered in the black list. When it is determined that the serving cell is registered in the blacklist, the communication terminal 100 controls the neighboring cell to be located in a neighboring cell that is not registered in the blacklist. As a result, the communication terminal 100 located in a base station with a high load can be moved to a base station with a low load. Instead of the black list, a white list in which cell identification information that satisfies the condition of low load is registered may be used. In this case, for example, when the communication terminal 100 is located in the cell of the wireless base station 200, the communication terminal 100 determines whether or not the serving cell is registered in the white list. When it is determined that the serving cell is not registered in the white list, the communication terminal 100 controls the neighboring cell to be located in the neighboring cell registered in the white list.

  When determining that the serving cell is registered in the blacklist, the communication terminal 100 further determines whether or not the radio wave reception intensity from the serving cell is lower than a predetermined serving cell threshold. Good. Then, when the communication terminal 100 determines that the radio wave reception intensity from the serving cell is not lower than the predetermined serving cell threshold value, the communication terminal 100 maintains the connection with the serving cell, and the reception strength of the radio wave from the serving cell. Is determined to be lower than a predetermined serving cell threshold value, control is performed so that the neighboring cell that is not registered in the blacklist among neighboring cells is located. Thus, when the communication terminal 100 is located in a radio base station with a high load, the communication terminal 100 can be moved to a base station with a low load when the radio wave reception intensity from the radio base station is weak. When the radio wave reception strength from the radio base station is strong and the communication quality is sufficient, the connection with the serving cell can be maintained.

  When the communication terminal 100 is controlled to be located in an adjacent cell that is not registered in the blacklist, the communication terminal 100 may be controlled to be located in an adjacent cell having high radio wave reception intensity received by the communication terminal 100. As a result, it is possible to suppress the occurrence of a situation in which the user experience of the user who uses the communication terminal 100 is deteriorated after being in the adjacent cell.

  The communication terminal 100, for example, controls so as to be located in an adjacent cell whose radio wave reception intensity is higher than a predetermined adjacent cell absolute threshold. Thereby, the communication quality provided to the user who uses the communication terminal 100 can be secured.

  In addition, the communication terminal 100 controls, for example, so that the radio wave reception intensity is in an adjacent cell that is higher than a value obtained by subtracting a predetermined adjacent cell relative threshold value from the radio wave reception intensity from the existing cell. As a result, deterioration from the serving cell can be reduced.

  The communication terminal 100 may generate and store a connection availability list indicating connection availability of each of the serving cell and the adjacent cell. For example, when the serving cell is not registered in the blacklist, the communication terminal 100 determines whether the communication terminal 100 and the serving cell can be connected. For example, when the serving cell is registered in the blacklist and the radio wave reception intensity from the serving cell is lower than the serving cell threshold, the communication terminal 100 determines whether the communication terminal 100 can be connected to the serving cell. Not connectable. In the communication terminal 100, for example, when the serving cell is registered in the blacklist and the radio wave reception intensity from the serving cell is not lower than the serving cell threshold, whether the communication terminal 100 and the serving cell can be connected or not Can be connected.

  For example, when the neighboring cell is registered in the blacklist, the communication terminal 100 determines whether or not the communication terminal 100 and the serving cell can be connected. For example, when the neighboring cell is not registered in the blacklist and the radio wave reception intensity from the neighboring cell is lower than the neighboring cell absolute threshold, the communication terminal 100 connects the communication terminal 100 to the connection availability of the serving cell. No. For example, when the neighboring cell is not registered in the blacklist and the radio wave reception intensity from the neighboring cell is higher than the neighboring cell absolute threshold, the communication terminal 100 connects the communication terminal 100 with the connection availability of the serving cell. Yes

  In the communication terminal 100, for example, the adjacent cell is not registered in the blacklist, and the radio wave reception intensity from the adjacent cell is obtained by subtracting a predetermined adjacent cell relative threshold value from the radio wave reception intensity from the serving cell. When it is lower than the value, the connection availability of the communication terminal 100 and the serving cell may be regarded as the connection availability. In the communication terminal 100, for example, the adjacent cell is not registered in the blacklist, and the radio wave reception intensity from the adjacent cell is obtained by subtracting a predetermined adjacent cell relative threshold value from the radio wave reception intensity from the serving cell. If the value is higher than the value, it may be determined that the communication terminal 100 can be connected to the serving cell.

  The black list may include a plurality of serving cell thresholds corresponding to the respective pieces of identification information of the plurality of cells. The serving cell threshold may be different for each cell. By this means, it is possible to use a serving cell threshold value suitable for each of the plurality of radio base stations 200. For example, by associating a higher serving cell threshold with a radio base station 200 having a higher transmitted field strength and associating a lower serving cell threshold with a wireless base station 200 having a lower transmitted field strength. It is possible to appropriately determine whether the radio wave reception intensity of the communication terminal 100 from the serving cell is high or low for the serving cell.

  The black list may include a plurality of adjacent cell absolute thresholds corresponding to the respective pieces of identification information of the plurality of cells. The adjacent cell absolute threshold may be different for each cell. By this means, it is possible to use the adjacent cell absolute threshold value suitable for each of the plurality of radio base stations 200. For example, by associating a higher adjacent cell absolute threshold with a wireless base station 200 having a higher transmitted radio field intensity and by associating a lower adjacent cell absolute threshold with a wireless base station 200 having a lower transmitted field intensity. It is possible to appropriately determine whether the radio wave reception intensity of the communication terminal 100 from the adjacent cell is high or low for the adjacent cell.

  The blacklist may include a plurality of adjacent cell relative thresholds corresponding to the respective pieces of identification information of the plurality of cells. The adjacent cell relative threshold may be different for each cell. Thereby, the adjacent cell relative threshold value suitable for each of the plurality of radio base stations 200 can be used. By setting the adjacent cell relative threshold value, it is possible to set a simple target value of SINR (Signal-to-Interference plus Noise power Ratio).

  The registration information management server 400 manages registration information. The registration information management server 400 may manage a blacklist, which is an example of registration information. The registration information management server 400 acquires, for example, load information indicating the loads of the plurality of cells, and generates a blacklist based on the acquired load information. For example, the registration information management server 400 includes, in the blacklist, the identification information of the cells whose average load is higher than a predetermined threshold value. The blacklist may be created by an operator of the registration information management server 400 or the like. The operator or the like, for example, negotiates a condition that the load is high, and generates a black list in which the identification information of cells satisfying the condition is registered.

  The registration information management server 400 provides the communication terminal 100 with the blacklist. The registration information management server 400 may send the blacklist to the communication terminal 100 via the network 300. The network 300 includes a wireless communication system such as a 3G communication system, an LTE communication system, a 5G communication system, and a Wi-Fi communication system. The network 300 may further include at least one of the Internet, a public wireless LAN (Local Area Network), and a dedicated network.

  The registration information management server 400 may provide the blacklist to the communication terminal 100 by storing the blacklist in a TFTP (Trial File Transfer Protocol) server. The communication terminal 100 may acquire the blacklist by accessing the TFTP server.

  FIG. 2 schematically shows an example of the functional configuration of the communication terminal 100. The communication terminal 100 includes a registration information storage unit 102, a registration information updating unit 104, a serving cell strength measurement unit 112, a serving cell strength storage unit 114, a serving cell strength acquisition unit 116, an adjacent cell strength measurement unit 122, an adjacent cell. Strength storage unit 124, adjacent cell strength acquisition unit 126, connection determination cell list storage unit 130, registration determination unit 142, connection determination cell list management unit 144, strength determination unit 146, non-communication detection unit 148, control execution unit 150, and The connection control unit 154 is provided. Note that it is not essential that the communication terminal 100 has all of these configurations.

  The registration information storage unit 102 stores registration information. The registration information storage unit 102 may store a blacklist as registration information. The registration information storage unit 102 may store the blacklist received from the registration information management server 400.

  The registration information update unit 104 updates the blacklist stored in the registration information storage unit 102. The registration information update unit 104 updates the blacklist by receiving the blacklist from the registration information management server 400, for example. The registration information update unit 104 may update the black list by replacing the black list stored in the registration information storage unit 102 with the black list received from the registration information management server 400. The registration information updating unit 104 may receive the blacklist from the registration information management server 400 by requesting the blacklist from the registration information management server 400. The communication terminal 100 requests the blacklist by transmitting Pull Request to the registration information management server 400, for example.

  The registration information updating unit 104, for example, the black list is updated regularly. The frequency of updating the blacklist may be about once or twice a month. The registration information update unit 104 can set the timing of updating the blacklist so that it can be cycle-compatible or calendar-compatible, for example. The registration information update unit 104 requests the registration information management server 400 for a blacklist according to a preset schedule, for example.

  The serving cell strength measuring unit 112 measures the strength of radio waves received from the serving cell of the communication terminal 100. The serving cell strength storage unit 114 stores the radio wave reception strength from the serving cell of the communication terminal 100 measured by the serving cell strength measuring unit 112.

  The serving cell strength acquisition unit 116 acquires the radio wave reception strength from the serving cell of the communication terminal 100. The serving cell strength acquisition unit 116 acquires the radio wave reception strength measured by the serving cell strength measurement unit 112, for example. The serving cell strength acquisition unit 116 acquires the radio wave reception strength stored in the serving cell strength storage unit 114, for example.

  The adjacent cell strength measuring unit 122 measures the radio wave reception strength from the adjacent cell of the communication terminal 100. The adjacent cell strength storage unit 124 stores the electric wave reception strength from the adjacent cell of the communication terminal 100 measured by the adjacent cell strength measurement unit 122.

  The adjacent cell strength acquisition unit 126 acquires the radio wave reception strength from the adjacent cell of the communication terminal 100. The adjacent cell strength acquisition unit 126 acquires, for example, the radio wave reception strength from the adjacent cell of the communication terminal 100 measured by the adjacent cell strength measurement unit 122. The adjacent cell strength acquisition unit 126 acquires, for example, the radio wave reception strength from the adjacent cell of the communication terminal 100 stored in the adjacent cell strength storage unit 124.

  The connection determination cell list storage unit 130 stores the connection determination cell list. In the connection determination cell list, the identification information of each of the plurality of cells and the availability of connection with the communication terminal 100 are associated with each other.

  The registration determination unit 142 determines whether or not the serving cell of the communication terminal 100 is registered in the blacklist stored in the registration information storage unit 102. The registration determination unit 142 determines, for example, when the communication terminal 100 is in the cell of the wireless base station 200, whether or not the cell in the cell is registered in the black list.

  The connection determination cell list management unit 144 manages the connection determination cell list stored in the connection determination cell list storage unit 130. The connection determination cell list management unit 144, for example, generates a connection determination cell list and stores it in the connection determination cell list storage unit 130. Further, the connection determination cell list management unit 144 updates the connection determination cell list stored in the connection determination cell list storage unit 130, for example.

  The connection determination cell list management unit 144 may update the connection determination cell list based on the determination result of the registration determination unit 142. For example, the connection determination cell list management unit 144, when the registration determination unit 142 determines that the serving cell is not registered in the black list, so that the cell identification information of the serving cell is associated with the connectable, Update the connection judgment cell list.

  The strength determination unit 146 determines whether or not the radio wave reception strength from the serving cell of the communication terminal 100 is lower than a predetermined serving cell threshold value. The strength determination unit 146, for example, when the registration determination unit 142 determines that the serving cell of the communication terminal 100 is registered in the blacklist, the strength determination unit 146 determines whether the serving cell strength acquisition unit 116 acquires from the serving cell. It is determined whether the radio wave reception intensity is lower than the serving cell threshold value. The strength determination unit 146 may use the serving cell threshold included in the black list stored in the registration information storage unit 102. The strength determination unit 146 may use the serving cell threshold value corresponding to the identification information of the serving cell. The adjacent cell strength acquisition unit 126 receives the radio wave from the adjacent cell of the communication terminal 100 when the strength determination unit 146 determines that the radio wave reception strength of the communication terminal 100 from the serving cell is lower than the serving cell threshold. You may get strength.

  The connection determination cell list management unit 144 may update the connection determination cell list stored in the connection determination cell list storage unit 130 based on the determination result of the strength determination unit 146. In the connection determination cell list management unit 144, for example, the registration determination unit 142 determines that the serving cell of the communication terminal 100 is registered in the black list, and the strength determination unit 146 determines that the communication terminal 100 is in the serving cell of the communication terminal 100. When it is determined that the radio wave reception intensity from the cell is lower than the serving cell threshold, the connection determination cell list is updated so that the connection identification is associated with the cell identification information of the serving cell. In addition, the connection determination cell list management unit 144, for example, is determined by the registration determination unit 142 that the serving cell of the communication terminal 100 is registered in the blacklist, and the strength determination unit 146 causes the communication terminal 100 of the communication terminal 100 to be registered. When it is determined that the radio wave reception intensity from the serving cell is not lower than the serving cell threshold, the connection determination cell list is updated so that the cell identification information of the serving cell is associated with the connectable.

  The non-communication detection unit 148 detects that the non-communication state has continued for a predetermined time after the communication between the communication terminal 100 and the radio base station 200 forming the serving cell is completed. The non-communication detection unit 148, for example, when the strength determination unit 146 determines that the radio reception strength from the serving cell of the communication terminal 100 is lower than the serving cell threshold, does not communicate after the communication ends. For a predetermined time. The predetermined time can be arbitrarily set, such as 10 milliseconds and 10 seconds.

  The control execution unit 150 executes control of the communication terminal 100. The control execution unit 150, for example, when the non-communication detection unit 148 detects that the non-communication state has continued for a predetermined time after the communication between the communication terminal 100 and the wireless base station 200 is detected, The communication connection between the communication terminal 100 and the wireless base station 200 is disconnected. Then, the control execution unit 150 causes the in-service cell strength measuring unit 112 to measure the radio wave reception intensity from the in-service cell and the adjacent cell strength measurement unit 122 to measure the radio wave reception intensity from the adjacent cell after the communication is disconnected.

  In addition, the control execution unit 150, for example, when the non-communication detection unit 148 detects that the state of not communicating after the communication between the communication terminal 100 and the wireless base station 200 is continued for a predetermined time. Then, the connection state between the communication terminal 100 and the wireless base station 200 is changed to the idle state. After the transition, the control execution unit 150 causes the serving cell strength measurement unit 112 to measure the radio wave reception intensity from the serving cell, and causes the adjacent cell strength measurement unit 122 to measure the radio wave reception intensity from the adjacent cell.

  The control execution unit 150 may execute control of the communication terminal 100 when the strength determination unit 146 determines that the radio wave reception strength from the serving cell of the communication terminal 100 is lower than the serving cell threshold. For example, when the strength determination unit 146 makes the determination, the control execution unit 150 disconnects the communication connection between the communication terminal 100 and the wireless base station 200, and causes the serving cell strength measurement unit 112 to switch the serving cell from the serving cell. Then, the adjacent cell strength measuring unit 122 is caused to measure the electric wave reception strength from the adjacent cell. Further, for example, when the strength determination unit 146 makes the determination, the control execution unit 150 transitions the connection state between the communication terminal 100 and the wireless base station 200 to the idle state, and the in-service cell strength measurement unit 112. To measure the radio wave reception intensity from the serving cell, and let the adjacent cell strength measurement unit 122 measure the radio wave reception intensity from the adjacent cell.

  The connection availability determination unit 152 determines availability of connection between the communication terminal 100 and the adjacent cell. The connection availability determination unit 152 determines whether or not the adjacent cell of the communication terminal 100 is registered in the blacklist stored in the registration information storage unit 102, for example. The connection availability determination unit 152, for example, when the strength determination unit 146 determines that the radio reception intensity from the serving cell of the communication terminal 100 is lower than the serving cell threshold, the neighboring cell of the communication terminal 100 is blacklisted. May be registered in.

  When the connection availability determination unit 152 determines that the adjacent cell of the communication terminal 100 is not registered in the blacklist, the radio reception intensity from the adjacent cell acquired by the adjacent cell strength acquisition unit 126 is higher than the adjacent cell absolute threshold. It may be determined whether or not. The connection availability determination unit 152 may use the adjacent cell absolute threshold included in the blacklist stored in the registration information storage unit 102. The connection availability determination unit 152 may use the adjacent cell absolute threshold value corresponding to the identification information of the serving cell. The connection availability determination unit 152 may determine the availability of connection between the communication terminal 100 and the adjacent cell when the radio wave reception intensity from the adjacent cell of the communication terminal 100 is higher than the adjacent cell absolute threshold.

  When the connection availability determination unit 152 determines that the adjacent cell of the communication terminal 100 is not registered in the blacklist, the radio wave reception intensity from the adjacent cell acquired by the adjacent cell strength acquisition unit 126 is the location of the communication terminal 100. It may be determined whether or not it is higher than a value obtained by subtracting the adjacent cell relative threshold value from the radio wave reception intensity from the cell. The connection availability determination unit 152 may use the adjacent cell relative threshold value included in the black list stored in the registration information storage unit 102. The connection availability determination unit 152 may use the adjacent cell relative threshold value corresponding to the identification information of the serving cell. The connection availability determination unit 152 determines that the radio wave reception intensity from the adjacent cell of the communication terminal 100 is higher than the value obtained by subtracting the adjacent cell relative threshold from the radio wave reception intensity of the communication terminal 100 from the serving cell. May be determined to be connectable with the adjacent cell.

  The connection availability determination unit 152 determines that the radio wave reception intensity from the adjacent cell of the communication terminal 100 is higher than the adjacent cell absolute threshold, and the radio wave reception intensity from the adjacent cell of the communication terminal 100 is from the serving cell of the communication terminal 100. If it is higher than the value obtained by subtracting the adjacent cell relative threshold from the radio wave reception intensity, the connection between the communication terminal 100 and the adjacent cell may be determined to be connectable.

  The adjacent cell absolute threshold may include the same frequency adjacent cell absolute threshold and the different frequency adjacent cell absolute threshold. When the in-service cell and the adjacent cell are cells having the same frequency, the connection availability determination unit 152 has a radio wave reception intensity from the adjacent cell of the communication terminal 100 higher than the same-frequency adjacent cell absolute threshold value corresponding to the in-service cell. In this case, it may be determined that connection is possible. When the in-service cell and the adjacent cell are cells of different frequencies, connection availability determination unit 152 has a radio wave reception intensity from the adjacent cell of communication terminal 100 higher than the different-frequency adjacent cell absolute threshold value corresponding to the in-service cell. In this case, it may be determined that connection is possible.

  The connection determination cell list management unit 144 may update the connection determination cell list stored in the connection determination cell list storage unit 130 based on the determination result of the connection availability determination unit 152. When the connection availability determination unit 152 determines that the connection availability between the communication terminal 100 and the adjacent cell is connection availability, the connection availability cell list management unit 144 determines the connection availability so that the connection availability is associated with the cell identification information of the adjacent cell. The cell list may be updated. When the connection availability determination unit 152 determines that the connection availability of the communication terminal 100 and the adjacent cell is connectable, the connection determination cell list management unit 144 determines that the cell identification information of the adjacent cell is associated with the connection availability. The cell list may be updated.

  The connection control unit 154 determines a cell in which the communication terminal 100 is located and controls the communication terminal 100 to be located in the cell. The connection control unit 154 determines the cell in which the communication terminal 100 is located, for example, based on the determination result of the strength determination unit 146. When the strength determination unit 146 determines that the radio wave reception intensity from the serving cell of the communication terminal 100 is lower than the serving cell threshold value, the connection control unit 154 makes a blacklist among neighboring cells of the communication terminal 100. The communication terminal 100 may be controlled to be located in an adjacent cell that is not registered. The connection control unit 154 may perform control so that the communication terminal 100 is located in the adjacent cell determined to be connectable by the connection permission / inhibition determination unit 152.

  The connection control unit 154 determines the cell in which the communication terminal 100 is located, for example, based on the connection determination cell list stored in the connection determination cell list storage unit 130. The connection control unit 154 may control the communication terminal 100 so as to maintain the coverage area of the communication terminal 100 in the serving cell when the connection availability of the serving cell is “connectable”. The connection control unit 154 controls the communication terminal 100 so that the communication terminal 100 is located in the connectable adjacent cell when the connectable cell is in the connectable cell and the connectable adjacent cell exists. You may control. The connection control unit 154 controls the communication terminal 100 to maintain the coverage area of the communication terminal 100 in the serving cell when the connection availability of the serving cell is connection availability and there is no adjacent cell that is connectable. You may control. In this case, the connection determination cell list management unit 144 may update the connection determination cell list stored in the connection determination cell list storage unit 130 so that the cell identification information of all cells corresponds to the connectable state.

  The connection determination cell list management unit 144, for example, when the connection control unit 154 fails to control the communication terminal 100 to be in the connectable cell, the connection identification is associated with the cell identification information of the cell, The connection determination cell list stored in the connection determination cell list storage unit 130 may be updated.

  When the communication control unit 154 determines that the communication terminal 100 is located in a cell other than the serving cell, the communication control unit 154 transmits a connection request to the radio base station 200 forming the determined cell, and You may control so that it may be located in the said cell. For example, when there are a plurality of connectable adjacent cells, the connection control unit 154 may transmit a connection request to the wireless base station 200 forming the adjacent cell having the highest radio wave reception intensity among the adjacent cells. ..

  When the connection control unit 154 determines that the communication terminal 100 is located in a cell other than the serving cell, the connection control unit 154 prevents the communication terminal 100 from being located in a cell other than the determined cell, thereby making the communication terminal 100 However, you may control so that it may exist in the determined cell. For example, the connection control unit 154 controls the communication terminal 100 so as not to establish a communication connection with the radio base station 200 that forms a cell other than the determined cell. For example, the connection control unit 154 rejects connection with cells other than the determined cell. Further, for example, the connection control unit 154 does not include measurement results of cells other than the determined cell in the Measurement Report.

  FIG. 3 schematically shows an example of the functional configuration of the registration information management server 400. The registration information management server 400 includes a base station information acquisition unit 402, a base station information storage unit 404, a registration information generation unit 406, an input reception unit 408, a registration information storage unit 410, a registration information request reception unit 412, and a registration information transmission unit 414. , And a registration information comparison / update unit 416. The registration information management server 400 does not necessarily have to have all of these configurations.

  The base station information acquisition unit 402 acquires base station information of a plurality of wireless base stations 200. The base station information includes load information indicating the load on the cell. The base station information acquisition unit 402 may be an example of a load information acquisition unit. The base station information may also include the radio wave transmission intensity in the cell.

  The base station information acquisition unit 402 receives, for example, base station information of the plurality of radio base stations 200 from each of the plurality of radio base stations 200 via the network 300. The base station information acquisition unit 402 receives, for example, the base station information of the plurality of radio base stations 200 from a device that collectively manages the base station information of the plurality of radio base stations 200 via the network 300. The base station information acquisition unit 402 may acquire the base station information of the plurality of wireless base stations 200 input by the operator of the registration information management server 400 or the like. Further, the base station information acquisition unit 402 may acquire the number of communication terminals 100 existing in the best server of the wireless base station 200 as the base station information. The base station information storage unit 404 stores the base station information of the plurality of wireless base stations 200 acquired by the base station information acquisition unit 402.

  The registration information generation unit 406 generates a blacklist in which cell identification information that satisfies the condition that the load is high is registered. The registration information generation unit 406 may generate the blacklist based on the base station information stored in the base station information storage unit 404. The registration information generation unit 406 generates the blacklist, for example, by including in the blacklist the cell identification information of the cell whose load indicated by the base station information is higher than a predetermined threshold.

  The registration information generation unit 406 may include the serving cell threshold in the blacklist. The registration information generation unit 406 may determine the serving cell threshold value corresponding to each of the plurality of cells based on the base station information stored in the base station information storage unit 404. For example, the registration information generation unit 406 determines the serving cell threshold value corresponding to the transmitted radio field intensity for each of the plurality of cells.

  The registration information generation unit 406 may include the adjacent cell absolute threshold and the adjacent cell relative threshold in the black list. The registration information generation unit 406 may determine the adjacent cell absolute threshold value and the adjacent cell relative threshold value corresponding to each of the plurality of cells, based on the base station information stored in the base station information storage unit 404.

  The registration information generation unit 406 may include the base station information in the black list. The registration information generation unit 406 includes, for example, the load information and the number of communication terminals 100 corresponding to the cell identification information in the black list.

  The registration information generation unit 406 may generate a blacklist every time the base station information acquisition unit 402 newly acquires the base station information and stores it in the base station information storage unit 404. Further, the registration information generation unit 406 may generate a blacklist according to a preset schedule. For example, the registration information generation unit 406 refers to the base station information stored in the base station information storage unit 404 when the timing to generate the blacklist arrives, and generates the blacklist based on the base station information. To do.

  The input receiving unit 408 receives input from an operator or the like of the registration information management server 400. The registration information generation unit 406 may generate the blacklist according to the input received by the input reception unit 408. The registration information generation unit 406 may generate a black list including cell identification information, a serving cell threshold, an adjacent cell absolute threshold, and an adjacent cell relative threshold, which are input by an operator or the like.

  The registration information storage unit 410 stores the blacklist generated by the registration information generation unit 406. The registration information request receiving unit 412 receives a blacklist request from the communication terminal 100.

  The registration information transmitting unit 414 transmits the blacklist to the communication terminal 100 via the network 300. The registration information transmission unit 414 transmits the blacklist stored in the registration information storage unit 410 to the communication terminal 100. For example, when the registration information request receiving unit 412 receives the blacklist request, the registration information transmitting unit 414 transmits the blacklist to the communication terminal 100 that has transmitted the request. The registration information transmitting unit 414 may limit the blacklist to be transmitted to the blacklist in the requested area in order to reduce the amount of transmission data.

  The registration information transmitting unit 414 may transmit the blacklist to the communication terminal 100 without depending on the request. For example, the registration information transmission unit 414 stores the history of the communication terminal 100 that has transmitted the blacklist, and when the blacklist stored in the registration information storage unit 410 is updated, the communication terminal included in the history. Send the blacklist to 100. The registration information transmitting unit 414 may transmit the blacklist to the communication terminal 100 according to a preset schedule.

  The registration information comparison unit 416 compares the blacklist stored in the registration information storage unit 410 with the base station information stored in the base station information storage unit 404. The registration information comparison unit 416 may update the blacklist as necessary based on the comparison result.

  For example, the registration information comparison unit 416 includes the number of communication terminals 100 existing in the best server of the wireless base station 200 stored in the base station information storage unit 404, and the blacklist stored in the registration information storage unit 410. Based on the comparison result with the base station information included in, the at least one of the serving cell threshold and the neighboring cell threshold included in the blacklist is updated.

  As a specific example, the registration information comparison unit 416, for each of the plurality of cells identified by the plurality of cell identification information included in the blacklist stored in the registration information storage unit 410, of the communication terminal 100 in the blacklist. The number is compared with the number of communication terminals 100 stored in the base station information storage unit 404. Then, the registration information comparison unit 416 uses the cell identification information of the cell in which the number of the latter is larger than that in the former, that is, the cell in which the number of the communication terminals 100 is larger than when the blacklist is generated. Correspondingly, the serving cell threshold value registered in the black list is increased. The registration information comparison unit 416 may lower the serving cell threshold value registered in the black list in association with the cell identification information of the cell in which the latter cell is smaller than the former cell. It is not necessary to change the coverage cell threshold. The registration information comparison unit 416 does not have to change the serving cell threshold for cells having the same number of former and latter cells.

  Further, as a specific example, the registration information comparison unit 416 lowers the absolute threshold value of the adjacent cell registered in the black list in association with the cell identification information of the cell in which the latter cell is larger than the former cell. The registration information comparison unit 416 does not have to change the adjacent cell absolute threshold for the cells having the same numbers of the former and the latter.

  Further, as a specific example, the registration information comparison unit 416 increases the neighboring cell relative threshold value registered in the black list in association with the cell identification information of the cell in which the latter cell is larger than the former cell. The registration information comparison unit 416 does not have to change the adjacent cell relative threshold for cells having the same number of former and latter cells.

  The registration information comparison unit 416 stores the blacklist stored in the registration information storage unit 410 and the blacklist stored in the base station information storage unit 404, for example, every time new base station information is stored in the base station information storage unit 404. The black list may be updated if necessary by making a comparison with the existing base station information. In addition, for example, when the registration information generation unit 406 generates the blacklist according to the preset schedule, the registration information comparison unit 416 determines that the base before the registration information generation unit 406 generates the blacklist according to the schedule. Each time new base station information is stored in the station information storage unit 404, the blacklist stored in the registration information storage unit 410 is compared with the base station information stored in the base station information storage unit 404. The blacklist may be updated as needed.

  FIG. 4 is an explanatory diagram for explaining a process in which the communication terminal 100 updates the connection determination cell list. Here, there are two adjacent cells 242 and 262 with respect to the communication terminal 100 located in the serving cell 222, and the registration information storage unit 102 of the communication terminal 100 stores the black shown in Table 1 below. The case where the list is stored will be described as an example. The serving cell 222 is formed by the radio base station 220. The adjacent cell 242 is formed by the radio base station 240. The adjacent cell 262 is formed by the radio base station 260.

  The black list in Table 1 includes high load cell discrimination information, a cell area electric field threshold value in a serving area, and an adjacent cell electric field threshold value. The high load cell discrimination information includes EARFCN (E-UTRAN Absolute Radio Frequency Channel Number), Cell Identity, and PCI (Physical Cell ID). EARFCN is information indicating the center frequency of the cell. Cell Identity and PCI are examples of cell identification information. The serving cell electric field threshold value is an example of a serving cell threshold value. The adjacent cell electric field threshold includes an Intra-F electric field threshold (relative value), an Intra-F electric field threshold (absolute value), and an Inter-F electric field threshold (absolute value). The Intra-F electric field threshold value (relative value) is an example of the adjacent cell relative threshold value. The Intra-F electric field threshold value (absolute value) is an example of the same frequency adjacent cell absolute threshold value. The Inter-F electric field threshold value (absolute value) is an example of the different frequency neighboring cell absolute threshold value.

  The communication terminal 100 determines whether or not the connection between the communication terminal 100 and the serving cell 222 is possible. Here, it is assumed that the cell identification information of the serving cell 222 is registered first in the black list in Table 1 and the radio wave reception intensity from the serving cell 222 is −80 dBm.

  First, the registration determination unit 142 determines whether the serving cell 222 is registered in the blacklist. In this example, the registration determination unit 142 determines that the serving cell 222 is registered in the blacklist.

  Next, the strength determination unit 146 determines whether or not the radio wave reception strength from the serving cell 222 is lower than the serving cell electric field threshold value associated with the cell identification information of the serving cell 222. Referring to Table 1, the serving cell electric field threshold value associated with the cell identification information is −80 dBm. Since the radio wave reception intensity from the serving cell 222 is −80 dBm, the strength determination unit 146 determines in this example that the radio wave reception intensity from the serving cell 222 is not lower than the serving cell electric field threshold value.

  The connection determination cell list management unit 144 determines that the strength of radio wave reception from the serving cell 222 is not lower than the serving cell electric field threshold value by the strength determination unit 146, and thus the connection determination cell list management unit 144 can connect to the cell identification information of the serving cell 222. The connection determination cell list stored in the connection determination cell list storage unit 130 is updated so that

  The communication terminal 100 may further determine whether or not the connection between the communication terminal 100 and the adjacent cell 242 is possible. Here, it is assumed that the cell identification information of the adjacent cell 242 is not registered in the blacklist of Table 1 and the radio wave reception intensity from the adjacent cell 242 is −105 dBm.

  The connection availability determination unit 152 determines whether or not the adjacent cell 242 is registered in the blacklist. In this example, the connection availability determination unit 152 determines that the adjacent cell 242 is not registered in the blacklist.

  Next, the connection availability determination unit 152 determines the connection availability based on the radio wave reception intensity from the adjacent cell 242 and the adjacent cell electric field threshold value associated with the cell identification information of the serving cell 222. Since the connection availability determination unit 152 has the same EARFCN of the serving cell 222 and the neighboring cell 242 of 40340, the radio reception intensity from the neighboring cell 242 is Intra-correlated with the cell identification information of the serving cell 222. F It is determined whether it is higher than the electric field threshold value (absolute value). Referring to Table 1, the Intra-F electric field threshold value (absolute value) associated with the cell identification information is −100 dBm. Since the radio wave reception intensity from the adjacent cell 242 is −105 dBm, the connection availability determination unit 152 determines that the radio wave reception intensity from the adjacent cell 242 is lower than the Intra-F electric field threshold value (absolute value). As a result, the connection availability determination unit 152 determines the availability of connection between the communication terminal 100 and the adjacent cell 242 as connection availability. The connection determination cell list management unit 144 updates the connection determination cell list stored in the connection determination cell list storage unit 130 so that the connection identification is associated with the cell identification information of the adjacent cell 242.

  The communication terminal 100 may further determine whether or not the connection between the communication terminal 100 and the adjacent cell 262 is possible. Here, it is assumed that the identification information of the adjacent cell 262 is not registered in the blacklist in Table 1 and the radio wave reception intensity from the adjacent cell 262 is −85 dBm.

  The connectability determination unit 152 determines whether or not the adjacent cell 262 is registered in the blacklist. In this example, the connection availability determination unit 152 determines that the adjacent cell 262 is not registered in the blacklist.

  Next, the connection availability determination unit 152 determines the connection availability based on the radio wave reception intensity from the adjacent cell 262 and the adjacent cell electric field threshold value associated with the cell identification information of the serving cell 222. Since the connection availability determination unit 152 has the same EARFCN of the serving cell 222 and the neighboring cell 262 of 40340, the radio reception intensity from the neighboring cell 262 is Intra-F associated with the identification information of the serving cell 222. It is determined whether it is higher than the electric field threshold value (absolute value). Referring to Table 1, the Intra-F electric field threshold value (absolute value) associated with the cell identification information of the serving cell 222 is −100 dBm. Since the radio wave reception intensity from the adjacent cell 262 is −85 dBm, the connection availability determination unit 152 determines that the radio wave reception intensity from the adjacent cell 262 is lower than the Intra-F electric field threshold value (absolute value). As a result, the connection availability determination unit 152 determines that the connection between the communication terminal 100 and the adjacent cell 242 is connectable. The connection determination cell list management unit 144 updates the connection determination cell list stored in the connection determination cell list storage unit 130 so that the cell identification information of the adjacent cell 262 corresponds to the connectable state.

  Table 2 below shows an example of the updated connection determination cell list. In Table 2, “OK” indicates that the connection with the communication terminal 100 is connectable, and “NG” indicates that the connection with the communication terminal 100 is not connectable.

  FIG. 5 schematically shows an example of the flow of processing by the communication terminal 100. The process illustrated in FIG. 5 will be described, for example, assuming that the communication terminal 100 is in the cell formed by the specific wireless base station 200 as a start state. The communication terminal 100 starts the process when the communication terminal 100 is powered on and the communication terminal 100 is in the cell, for example.

  In step (step may be abbreviated as S) 102, the registration determination unit 142 determines whether the serving cell is registered in the blacklist. If it is determined that it is registered, the process proceeds to S104. If it is determined that it is not registered, the process proceeds to S108.

  In S104, the strength determination unit 146 determines whether the radio wave reception strength from the serving cell is lower than a predetermined serving cell threshold. When it is determined that it is low, the process proceeds to S106, and when it is determined that it is not low, the process proceeds to S108.

  In S106, the connection determination cell list management unit 144 updates the connection determination cell list stored in the connection determination cell list storage unit 130 such that the connection identification is associated with the cell identification information of the serving cell.

  In S108, the connection determination cell list management unit 144 updates the connection determination cell list stored in the connection determination cell list storage unit 130 so that the cell identification information of the serving cell is associated with the connectable state.

  In S110, the connection availability determination unit 152 determines whether or not the adjacent cell is registered in the black list. If it is determined that it is not registered, the process proceeds to S112, and if it is determined that it is registered, the process proceeds to S116.

  In S112, the connection availability determination unit 152 determines whether or not the radio wave reception intensity from the adjacent cell is higher than a predetermined adjacent cell threshold value. If it is determined to be high, the process proceeds to S114, and if it is determined to be not high, the process proceeds to S116.

  In S114, the connection determination cell list management unit 144 updates the connection determination cell list stored in the connection determination cell list storage unit 130 so that the cell identification information of the adjacent cell corresponds to the connectable state.

  In S116, the connection determination cell list management unit 144 updates the connection determination cell list stored in the connection determination cell list storage unit 130 so that the connection identification is associated with the cell identification information of the adjacent cell.

  In S118, the connection availability determination unit 152 confirms whether the determination has been completed for all adjacent cells. When it is determined whether the connection with all the adjacent cells is possible, the process proceeds to S120. When it is not determined whether the connection with all the adjacent cells is determined, the process returns to S110, and it is determined whether the connection with the adjacent cells for which the connection with the communication terminal 100 is not determined is determined.

  In S120, the connection control unit 154 determines whether or not there is an adjacent cell that can be connected to the communication terminal 100. If it is determined that there is a connectable adjacent cell, the process proceeds to S122. If it is determined that there is no adjacent cell that can be connected, the process ends. The connection control unit 154 may refer to the connection determination cell list stored in the connection determination cell list storage unit 130 to determine whether or not there is a connectable adjacent cell.

  When it is determined in S120 that there is no connectable neighboring cell, the communication determination terminal updates the connection determination cell list so that the communication terminal 100 is located in the cell with the highest electric field strength, and controls the cell. You may. For example, the connection determination cell list management unit 144 compares the radio reception strengths of all cells when the connection determination results are NG for all cells included in the connection determination cell list, and determines the highest radio reception strength. The connection determination result of the cell with a high value is updated to OK. Further, for example, the connection determination cell list management unit 144 compares the radio reception strengths of the adjacent cells that are not registered in the blacklist among all the cells included in the connection determination cell list, and the radio reception strength is the highest. The connection determination result of the adjacent cell is updated to OK. As a result, the communication terminal 100 can be located in the adjacent cell having the highest radio wave reception intensity among the adjacent cells not registered in the blacklist.

  In S122, the connection control unit 154 controls the communication terminal 100 so that the communication terminal 100 is located in an adjacent cell that can be connected to the communication terminal 100. Then, the process ends.

  FIG. 6 schematically shows an example of the flow of processing by the communication terminal 100. The process illustrated in FIG. 6 will be described with the start state being the state in which the communication terminal 100 is in the cell formed by the specific wireless base station 200.

  In S202, the communication terminal 100 communicates with the wireless base station 200 forming a serving cell with the communication terminal 100. The communication terminal 100 relays communication between the user terminal 500 and the communication terminal 100.

  In S204, the non-communication detection unit 148 determines whether or not the communication between the communication terminal 100 and the wireless base station 200 forming the serving cell has ended. If the communication has ended, the process proceeds to S206, and if the communication has not ended, the process returns to S202.

  In S206, the non-communication detection unit 148 determines whether or not the non-communication state has continued for a predetermined time after the communication between the communication terminal 100 and the wireless base station 200 forming the serving cell is completed. judge. When it is determined that the state of not communicating has continued for the predetermined time, the process proceeds to S208. If the communication terminal 100 resumes communication with the wireless base station 200 before the non-communication state continues for a predetermined time, the process returns to S202.

  In S208, the control execution unit 150 disconnects the communication connection between the communication terminal 100 and the wireless base station 200 forming the serving cell. S208 may be replaced by a process in which the control execution unit 150 transitions the connection state between the communication terminal 100 and the radio base station 200 forming the serving cell to the idle state.

  In S210, the serving cell strength measurement unit 112 measures the radio wave reception intensity of the serving cell, and the adjacent cell strength measurement unit 122 measures the radio wave reception intensity of the adjacent cell. In S212, the connection determination cell list management unit 144 updates the connection determination cell list stored in the connection determination cell list storage unit 130 as in the process of FIG.

  In the process flow shown in FIG. 6, S204, S206, and S208 intentionally make the wireless base station 200 forming the serving cell unresponsive so that the communication connection with the wireless base station 200 is established. It may be replaced with controlling to disconnect. When the communication terminal 100 has a mode for turning off the wireless communication function of the communication terminal 100, S204, S206, and S208 set the mode and disconnect the communication connection with the wireless base station 200. However, after that, the setting of the mode may be canceled.

  The process illustrated in FIG. 6 is performed by the communication terminal 100 when the communication state between the communication terminal 100 and the wireless base station 200 forming the serving cell is terminated and the non-communication state continues for a predetermined time. Then, the communication connection with the wireless base station 200 is disconnected and the connection determination cell list stored in the connection determination cell list storage unit 130 is updated. When the non-communication state continues for a predetermined time, there is a high possibility that the non-communication state will continue for a while thereafter. By disconnecting the communication connection with the wireless base station 200 at a timing when the state of not communicating is likely to continue, it is possible to suppress deterioration of the user experience of the user terminal 500 due to the disconnection of the communication connection. Further, the connection hold time in the absence of communication between the communication terminal 100 and the wireless base station 200 is specified by the network side, but by setting a predetermined time to a time shorter than the connection hold time, Since it becomes possible to disconnect in a shorter time than the time designated by the side, the load on the radio base station 200 can be reduced.

  FIG. 7 schematically shows an example of the flow of processing by the communication terminal 100. The process illustrated in FIG. 7 will be described with the state in which the communication terminal 100 is in the cell formed by the specific radio base station 200 as a start state.

  In S302, the communication terminal 100 communicates with the wireless base station 200 forming a serving cell with the communication terminal 100. The communication terminal 100 relays communication between the user terminal 500 and the communication terminal 100.

  In S304, communication terminal 100 determines whether or not the mobility function has occurred. The mobility function is a function of switching the connection destination of the communication terminal 100 from the serving cell to the adjacent cell due to the movement of the communication terminal 100, the change of the radio wave condition around the communication terminal 100, or the like. Good. The mobility function is, for example, handover to another cell (Handover), cell reselection (Reselection), or the like. When it is determined that the mobility function has occurred, the process proceeds to S306. When it is determined that the mobility function has not occurred, the process returns to S302.

  In S306, the connection control unit 154 refers to the connection determination cell list stored in the connection determination cell list storage unit 130 to determine whether or not the communication terminal 100 can be connected to the adjacent cell that is the switching destination. When it is determined that the connection with the adjacent cell as the switching destination is connectable, the communication terminal 100 executes the mobility function. When it is determined that the connection with the adjacent cell as the switching destination is connection / denial, the process proceeds to S308.

  In S308, the connection control unit 154 controls such that the adjacent cell that is the switching destination and is not connected to the communication terminal 100 does not establish a communication connection. For example, the connection control unit 154 rejects the connection with the adjacent cell that is the connection destination and is the switching destination. In addition, for example, the connection control unit 154 does not include the measurement result of the adjacent cell that is the connection destination and is the switching destination, in the Measurement Report.

  In the process flow shown in FIG. 7, when the communication connection with the wireless base station 200 forming the serving cell is not connectable due to a wave stop or the like, the communication terminal 100 does not refer to the connection determination cell list. Mobility functions may be performed.

  In the processing illustrated in FIG. 7, when the mobility function occurs, the communication terminal 100 refers to the connection determination cell list stored in the connection determination cell list storage unit 130 to refer to the communication terminal 100 and the adjacent cell that is the switching destination. Determine whether the connection is possible. As a result of the determination, when the connection with the adjacent cell of the switching destination is connection / non-connection, the communication terminal 100 controls so that the adjacent cell of the switching destination and the communication terminal 100 do not establish a communication connection. The communication terminal 100 determines the mobility function and controls the communication connection with the adjacent cell of the switching destination based on the determination result, so that the user of the user who uses the communication terminal 100 can visit the adjacent cell of the switching destination. It is possible to suppress a situation in which the user's experience is deteriorated. Further, the communication terminal 100 may measure the radio wave reception intensity of the serving cell and the radio wave reception intensity of the switching destination adjacent cell when the connection availability with the switching destination adjacent cell is connection / disconnection. Then, the radio reception intensity of the measured adjacent cell of the switching destination is higher than the adjacent cell absolute threshold corresponding to the serving cell, and from the radio reception intensity from the serving cell, the adjacent cell relative threshold corresponding to the serving cell. When it is higher than the value obtained by subtracting, the communication terminal 100 may update the connection determination cell list so that the cell identification information of the adjacent cell of the switching destination corresponds to the cell identification information, and execute the mobility function.

  FIG. 8 schematically shows an example of the flow of processing by the registration information management server 400. Here, an example of the flow of processing from the base station information acquisition unit 402 acquiring base station information to the registration information transmission unit 414 transmitting registration information will be described.

  In S402, the base station information acquisition unit 402 acquires the base station information of the plurality of wireless base stations 200. In S404, the base station information storage unit 404 stores the plurality of base station information acquired by the base station information acquisition unit 402 in S402.

  If the registration information has not been stored in the registration information storage unit 410 (No in S406), the process proceeds to S408, and if the registration information has been stored (Yes in S406), the process proceeds to S412. In step S408, the registration information generation unit 406 generates registration information based on the base station information stored in the base station information storage unit 404. In S410, the registration information storage unit 410 stores the registration information generated in S408.

  In S412, the registration information comparison unit 416 registers the first cell identification information in the registration information stored in the registration information storage unit 410 in the registration information in association with the cell identification information. The number of terminals 100 is compared with the number of communication terminals 100 stored in the base station information storage unit 404 and included in the base station information corresponding to the cell identified by the cell identification information, It is determined whether the number of communication terminals 100 is increasing. If it is determined that the number is increasing, the process proceeds to S414. In S414, the registration information comparison unit 416 may update at least one of the serving cell threshold, the adjacent cell absolute threshold, and the adjacent cell relative threshold in the registration information. The registration information comparison unit 416 does not update, for example, when the increase number is smaller than a predetermined threshold value, and updates it when the increase number is large. The registration information comparison unit 416 repeats S412 and S414 for all cells in the registration information.

  In S416, the registration information transmission unit 414 transmits the registration information stored in the registration information storage unit 410 to the communication terminal 100. Then, the process ends.

  FIG. 9 schematically shows an example of the hardware configuration of a computer 1000 that functions as the communication terminal 100. The program installed in the computer 1000 causes the computer 1000 to function as one or more “units” of the apparatus according to the above-described embodiment, or causes the computer 1000 to perform an operation associated with the apparatus according to the above-described embodiment or the one or A plurality of “sections” may be executed, and / or the computer 1000 may execute the processes according to the above-described embodiments or the stages of the processes. Such programs may be executed by CPU 1012 to cause computer 1000 to perform certain operations associated with some or all of the blocks in the flowcharts and block diagrams described herein.

  The computer 1000 according to this embodiment includes a CPU 1012, a RAM 1014, and a graphic controller 1016, which are interconnected by a host controller 1010. Computer 1000 also includes input / output units such as communication interface 1022 and storage device 1024, which are connected to host controller 1010 via input / output controller 1020. The storage device 1024 may be a hard disk drive, a solid state drive, or the like. The computer 1000 also includes a ROM 1030 and an input / output unit such as a touch panel, which are connected to the input / output controller 1020 via an input / output chip 1040.

  The CPU 1012 operates according to programs stored in the ROM 1030 and the RAM 1014 to control each unit. The graphic controller 1016 acquires image data generated by the CPU 1012 into a frame buffer or the like provided in the RAM 1014 or itself, and causes the image data to be displayed on the display device 1018.

  The communication interface 1022 communicates with other electronic devices via a network. The storage device 1024 stores programs and data used by the CPU 1012 in the computer 1000.

  The ROM 1030 stores therein a boot program or the like executed by the computer 1000 at the time of activation, and / or a program dependent on the hardware of the computer 1000. The I / O chip 1040 may also connect various I / O units to the I / O controller 1020 via USB ports, parallel ports, serial ports, keyboard ports, mouse ports, etc.

  The program is provided by a computer-readable storage medium such as an IC card. The program is read from the computer-readable storage medium, installed in the storage device 1024, the RAM 1014, or the ROM 1030, which is also an example of the computer-readable storage medium, and executed by the CPU 1012. The information processing described in these programs is read by the computer 1000 and brings about the cooperation between the programs and the various types of hardware resources described above. An apparatus or method may be configured by implementing the operation or processing of information according to the use of the computer 1000.

  For example, when communication is executed between the computer 1000 and an external device, the CPU 1012 executes the communication program loaded in the RAM 1014, and performs the communication process on the communication interface 1022 based on the process described in the communication program. You may order. Under the control of the CPU 1012, the communication interface 1022 reads the transmission data stored in the transmission buffer area provided in the recording medium such as the RAM 1014, the storage device 1024, or the IC card, and the read transmission data is transmitted to the network. The reception data transmitted or received from the network is written in a reception buffer area or the like provided on the recording medium.

  Further, the CPU 1012 allows the RAM 1014 to read all or necessary portions of files or databases stored in the storage device 1024 or an external recording medium such as an IC card, and various types of data on the RAM 1014 can be read. The processing may be executed. CPU 1012 may then write back the processed data to an external storage medium.

  Various types of information such as various types of programs, data, tables, and databases may be stored on the recording medium and processed. The CPU 1012, for data read from the RAM 1014, is described throughout the present disclosure and includes various types of operations, information processing, conditional judgment, conditional branching, unconditional branching, and information retrieval specified by the instruction sequence of the program. Various types of processing may be performed, including / replacement, etc., and the result is written back to RAM 1014. Further, the CPU 1012 may search for information in files, databases, etc. in the recording medium. For example, when a plurality of entries each having the attribute value of the first attribute associated with the attribute value of the second attribute are stored in the recording medium, the CPU 1012 selects the first entry from the plurality of entries. Search for an entry that matches the specified attribute value of the attribute, read the attribute value of the second attribute stored in the entry, and set it as the first attribute that satisfies the predetermined condition. The attribute value of the associated second attribute may be obtained.

  The programs or software modules described above may be stored on a computer-readable storage medium on or near computer 1000. Further, a recording medium such as a hard disk or a RAM provided in a server system connected to a dedicated communication network or the Internet can be used as a computer-readable storage medium, whereby the program can be stored in the computer 1000 via the network. provide.

  The blocks in the flow charts and block diagrams in this embodiment may represent the steps of a process in which an operation is performed or the “unit” of a device that is responsible for performing the operation. Specific steps and "parts" are provided along with dedicated circuitry, programmable circuitry provided with computer readable instructions stored on a computer readable storage medium, and / or computer readable instructions stored on a computer readable storage medium. It may be implemented by the processor. Dedicated circuits may include digital and / or analog hardware circuits, and may include integrated circuits (ICs) and / or discrete circuits. Programmable circuits include, for example, field programmable gate arrays (FPGAs), programmable logic arrays (PLAs), and the like, logical product, logical sum, exclusive logical sum, negative logical product, negative logical sum, and other logical operations. , Reconfigurable hardware circuits, including flip-flops, registers, and memory elements.

  Computer readable storage media may include any tangible device capable of storing instructions executed by a suitable device, such that a computer readable storage medium having instructions stored therein is a flowchart or block diagram. A product will be provided that includes instructions that can be executed to create the means for performing the specified operations. Examples of computer readable storage media may include electronic storage media, magnetic storage media, optical storage media, electromagnetic storage media, semiconductor storage media, and the like. More specific examples of the computer readable storage medium include a floppy (registered trademark) disk, a diskette, a hard disk, a random access memory (RAM), a read only memory (ROM), and an erasable programmable read only memory (EPROM or flash memory). , Electrically erasable programmable read only memory (EEPROM), static random access memory (SRAM), compact disc read only memory (CD-ROM), digital versatile disc (DVD), Blu-ray (registered trademark) disc, memory stick , Integrated circuit cards, etc. may be included.

  Computer readable instructions include assembler instructions, instruction set architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state setting data, or object oriented programming such as Smalltalk, JAVA, C ++, etc. Language, and any source code or object code written in any combination of one or more programming languages, including conventional procedural programming languages such as the "C" programming language or similar programming languages. Good.

  Computer readable instructions are instructions for a general purpose computer, special purpose computer, or processor of another programmable data processing device, or programmable circuit, to generate means for performing the operations specified in a flowchart or block diagram. A general purpose computer, a special purpose computer, or other programmable data processing, locally or via a wide area network (WAN) such as a local area network (LAN), the Internet, etc., to execute the computer readable instructions. It may be provided in the processor of the device, or in a programmable circuit. Examples of processors include computer processors, processing units, microprocessors, digital signal processors, controllers, microcontrollers, and the like.

  Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is obvious to those skilled in the art that various changes or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiment added with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and steps in the devices, systems, programs, and methods shown in the claims, the specification, and the drawings is "preceding" or "prior to". It should be noted that the output of the previous process can be realized in any order unless the output of the previous process is used in the subsequent process. Even if the operation flow in the claims, the description, and the drawings is described using “first,” “next,” and the like for convenience, it means that it is essential to carry out in this order. Not a thing.

10 system, 100 communication terminal, 102 registration information storage unit, 104 registration information update unit, 112 in-cell cell strength measurement unit, 114 in-cell cell strength storage unit, 116 in-cell cell strength acquisition unit, 122 adjacent cell strength measurement unit, 124 adjacent cell strength storage unit, 126 adjacent cell strength acquisition unit, 130 connection determination cell list storage unit, 142 registration determination unit, 144 connection determination cell list management unit, 146 strength determination unit, 148 non-communication detection unit, 150 control execution unit , 152 connection availability determination unit, 154 connection control unit, 200 wireless base station, 220 wireless base station, 222 existing cell, 240 wireless base station, 242 adjacent cell, 260 wireless base station, 262 adjacent cell, 300 network, 400 registration Information management server, 402 Base station information acquisition unit, 404 Base station information storage unit, 406 Registration information generation unit, 408 input reception unit, 410 registration information storage unit, 412 registration information request reception unit, 414 registration information transmission unit, 416 registration information comparison unit, 500 user terminal, 1000 computer, 1010 host controller, 1012 CPU, 1014 RAM, 1016 graphic controller, 1018 display device, 1020 input / output controller, 1022 communication interface, 1024 storage device, 1030 ROM, 1040 input / output chip

Claims (16)

A communication terminal which is located in a cell formed by a radio base station and relays communication between the radio base station and a user terminal,
A registration information storage unit for storing the registration information received from the registration information management server identification information satisfy cells that load is high to manage the registration information that is registered,
A registration determination unit that determines whether or not the serving cell of the communication terminal is registered in the registration information,
When it is determined that the registration is determined by the registration determination unit, a strength determination unit that determines whether or not the radio wave reception intensity from the serving cell of the communication terminal is lower than a predetermined serving cell threshold value. ,
A connection control unit that controls the communication terminal so that the communication terminal is located in an adjacent cell that is not registered in the registration information among the adjacent cells of the communication terminal when the strength determination unit determines that the communication terminal is low. Communication terminal. The registration information includes a serving cell threshold value associated with the identification information of the cell,
The strength determination unit, when it is determined that the registration determination unit is registered, the radio reception intensity from the serving cell of the communication terminal is lower than the serving cell threshold value corresponding to the serving cell. The communication terminal according to claim 1, which determines whether or not it is. When it is determined to be low by the strength determination unit, an adjacent cell strength acquisition unit that acquires the radio wave reception strength from the adjacent cell of the communication terminal,
A connection availability determination unit that determines availability of connection between the communication terminal and the adjacent cell based on the radio wave reception intensity acquired by the adjacent cell intensity acquisition unit,
The communication terminal according to claim 1, wherein the connection control unit controls the communication terminal so that the communication terminal is located in an adjacent cell determined to be connectable by the connection permission / inhibition determination unit. The registration information includes an adjacent cell absolute threshold associated with the cell identification information,
The communication according to claim 3, wherein the connection availability determination unit determines that connection is possible when the radio wave reception intensity acquired by the adjacent cell intensity acquisition unit is higher than the adjacent cell absolute threshold value corresponding to the serving cell. Terminal. The registration information is associated with the identification information of the cell, including the same frequency adjacent cell absolute threshold and different frequency adjacent cell absolute threshold,
The connection availability determination unit, when the serving cell and the neighboring cell are cells of the same frequency, the radio reception strength acquired by the neighboring cell strength acquisition unit is the same frequency neighbor corresponding to the serving cell. If it is determined that connection is possible when it is higher than the cell absolute threshold value, and the neighboring cell and the neighboring cell are cells of different frequencies, the radio reception strength acquired by the neighboring cell strength acquisition unit is in the serving cell. The communication terminal according to claim 3, wherein connection is determined to be possible if the absolute value is higher than the corresponding absolute threshold of the different frequency neighboring cell. The registration information includes an adjacent cell relative threshold value associated with the identification information of the cell,
The connection availability determination unit subtracts the adjacent cell relative threshold value corresponding to the serving cell from the reception strength of the radio wave received by the neighboring cell strength acquisition unit from the serving cell of the communication terminal. The communication terminal according to claim 3, wherein connection is determined to be possible when the value is higher than the value. The registration information includes an adjacent cell absolute threshold and an adjacent cell relative threshold associated with the identification information of the cell,
The connection availability determination unit, the radio wave reception intensity acquired by the adjacent cell strength acquisition unit is higher than the adjacent cell absolute threshold corresponding to the serving cell, and, the radio wave reception intensity acquired by the adjacent cell strength acquisition unit is The connection is determined to be possible when it is higher than a value obtained by subtracting the adjacent cell relative threshold value corresponding to the existing cell from the radio wave reception intensity from the existing cell of the communication terminal. Communication terminal. When it is determined to be low by the strength determination unit, after the communication between the communication terminal and the radio base station forming the serving cell is completed, the state of not communicating has continued for a predetermined time. A non-communication detection unit that detects that
An adjacent cell strength measuring unit for measuring the radio wave reception strength from the adjacent cell of the communication terminal according to the detection by the non-communication detecting unit,
The communication terminal according to any one of claims 3 to 7, wherein the adjacent cell strength acquisition unit acquires the radio wave reception strength measured by the adjacent cell strength measurement unit.   The adjacent cell strength measuring unit, in response to the detection by the non-communication detecting unit, after disconnecting the communication connection between the wireless base station forming the serving cell and the communication terminal, adjacent to the communication terminal The communication terminal according to claim 8, which measures a radio wave reception intensity from a cell.   The adjacent cell strength measurement unit, in response to the detection by the non-communication detection unit, after the connection state with the radio base station forming the serving cell transitions to an idle state, the adjacent cell of the communication terminal The communication terminal according to claim 8, which measures a radio wave reception intensity from the communication terminal. A connection determination cell list storage unit that stores a connection determination cell list in which the connection availability of the communication terminal and the adjacent cell determined by the connection availability determination unit is registered,
The connection control unit refers to the connection determination cell list when the mobility function of switching the connection destination of the communication terminal to the adjacent cell occurs, and the connection destination cell is the connection determination cell. The communication terminal according to any one of claims 3 to 10, which, when registered in the list, controls so that the communication terminal and the adjacent cell of the switching destination do not establish a communication connection. Requesting the registration information according to a preset schedule to the registration information management server comprises a registration information updating unit that updates the registration information by receiving the registration information from the registration information management server, The communication terminal according to any one of claims 1 to 11.   A program for causing a computer to function as the communication terminal according to any one of claims 1 to 12. A method performed by a communication terminal, which is located in a cell formed by a radio base station and relays communication between the radio base station and a user terminal,
Determining a serving cell of the communication terminal, whether or not it is registered in the registration information received from the registration information management server identification information satisfy cells that load is high to manage the registration information registered Registration determination step to
When it is determined that it is registered in the registration determination step, a strength determination step of determining whether the radio reception strength from the serving cell of the communication terminal is lower than a predetermined serving cell threshold value. ,
A connection control step of controlling the communication terminal so that the communication terminal is located in an adjacent cell that is not registered in the registration information among the adjacent cells of the communication terminal when it is determined to be low in the strength determination step. Method. A communication terminal according to any one of claims 1 to 12 ,
System comprising a said registration information management server. The registration information management server,
A load information acquisition unit that acquires load information indicating each load of a plurality of cells,
A registration information generation unit that generates the registration information based on the load information acquired by the load information acquisition unit;
The registration information transmitting unit that transmits the registration information to the communication terminal.