JP6694909B2 - Communication terminal and program - Google Patents

Description

  The present invention relates to a communication terminal and a program.

In a conventional LTE (Long Term Evolution) communication system, an eNB activates a timer when communication with a UE is terminated, and when the timer exceeds a threshold value, an eRC (Radio Resource Control) to the UE is performed. The UE has been transitioned to the idle state by transmitting a Connection Release (see, for example, Patent Document 1).
[Prior Art Document]
[Patent Document]
[Patent Document 1] JP-A-2014-207582

  It is desirable to provide a technique capable of appropriately handling when the UE cannot receive the RRC Connection Release.

  According to the first aspect of the present invention, a communication terminal is provided. The communication terminal has a measuring unit that measures the time from the end of communication with the wireless base station to the reception of the connection release message from the wireless base station when the communication terminal is in the connected state in which the communication terminal is in communication connection with the wireless base station. You may be prepared. The communication terminal may include a setting unit that sets, based on the time measured by the measuring unit, a time-out value indicating a time from the end of communication with the wireless base station to the transition of the communication terminal to the idle state. The communication terminal may include a state transition unit that transitions the communication terminal to an idle state based on the timeout value.

  The state transition unit may transition the communication terminal to an idle state when the communication terminal is in the connected state and receives a connection release message from the radio base station. In the case where the communication terminal is in the connection state, the state transition unit did not communicate with the radio base station from the end of communication with the radio base station until the time indicated by the timeout value elapses. In this case, the communication terminal may transition to the idle state. The state transition unit, when the communication terminal is in the connection state, from the wireless base station to the connection release message from the end of communication with the wireless base station until the time indicated by the timeout value elapses. When not receiving, the communication terminal may transition to the idle state.

  The setting unit may set the timeout value based on the plurality of times measured by the measuring unit. The setting unit may set the timeout value based on an average of the plurality of times measured by the measuring unit. The setting unit may set the timeout value to indicate a time obtained by adding a predetermined time to the average of the plurality of times measured by the measuring unit.

  The setting unit may set the timeout value so as to indicate a time obtained by adding a predetermined time to the time measured by the measuring unit. In the case where the communication terminal is in the connected state, the setting unit sets the timeout value to indicate a time obtained by adding a predetermined time to the first time measured by the measurement unit, When a connection release message is received from the wireless base station after the first time has elapsed from the end of communication with the wireless base station and before the time indicated by the timeout value has elapsed. The time-out value may be set to indicate a time obtained by adding the predetermined time to the time from the end of communication with the radio base station to the reception of the connection release message.

  In the case where the communication terminal is in the connected state, the setting unit sends the connection release message from the wireless base station before the time indicated by the timeout value elapses from the end of communication with the wireless base station. When received, the timeout value may be set based on the time from the end of communication with the wireless base station until the reception of the connection release message. In the case where the communication terminal is in the connected state, the setting unit sends the connection release message from the wireless base station before the time indicated by the timeout value elapses from the end of communication with the wireless base station. It may have a counting unit for counting the number of times received, when the number of times counted by the counting unit becomes equal to a predetermined number, the connection release message from the end of communication with the wireless base station The timeout value may be set based on the time until reception.

  The communication terminal may include an information acquisition unit that acquires the number of Repetitions set in communication with the wireless base station, and the setting unit may set a timeout value for each number of Repetition, and the state transition may be performed. The unit may determine whether to shift the communication terminal to the idle state based on a timeout value corresponding to the number of Repetitions acquired by the information acquisition unit. The communication terminal may include a distance acquisition unit that acquires a distance between the communication terminal and the wireless base station, the setting unit may set a timeout value for each distance between the communication terminal and the wireless base station. The state transition unit may determine whether to transition the communication terminal to the idle state, based on a timeout value corresponding to the distance acquired by the distance acquisition unit. The setting unit may set a timeout value for each group of wireless base stations, the state transition unit, based on a timeout value corresponding to the group to which the wireless base station to which the communication terminal is communicatively connected, It may be determined whether or not to shift the communication terminal to the idle state. The setting unit may set a timeout value for each radio base station, the state transition unit, based on the timeout value corresponding to the radio base station with which the communication terminal is communicatively connected, the communication terminal It may be determined whether or not to transition to the idle state.

  The connection state may be RRC Connected State, the idle state may be RRC Idle State, and the connection release message may be RRC Connection Release. The communication terminal may be an IoT device.

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

  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 communication environment of communication terminal 100. An example of the flow of communication between the communication terminal 100 and the wireless base station 30 is schematically shown. An example of the flow of communication between the communication terminal 100 and the wireless base station 30 is schematically shown. An example of the flow of communication between the communication terminal 100 and the wireless base station 30 is schematically shown. An example of the flow of communication between the communication terminal 100 and the wireless base station 30 is schematically shown. An example of the flow of communication between the communication terminal 100 and the wireless base station 30 is schematically shown. An example of the timeout value table 161 is schematically shown. An example of the timeout value table 162 is schematically shown. An example of the timeout value table 163 is schematically shown. An example of the timeout value table 164 is schematically shown. 1 schematically shows an example of the functional configuration of the communication terminal 100. 1 schematically shows an example of a hardware configuration of a computer 900 that functions as the 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 the communication environment of the communication terminal 100. The communication terminal 100 belongs to the communication system 10. The communication system 10 includes a network 20 and a radio base station 30. The communication system 10 may be a so-called mobile communication system.

  The communication system 10 includes, for example, so-called 3G (third generation mobile communication system), LTE system, so-called 4G (fourth generation mobile communication system), so-called 5G (fifth generation mobile communication system), and mobile communication after 5G. It may be a system or the like. Here, a case where the communication system 10 is an LTE system will be mainly described as an example.

  The communication terminal 100 may be any terminal as long as it can wirelessly communicate with the wireless base station 30. Here, a case where the communication terminal 100 is a so-called IoT (Internet of Thing) device will be mainly described as an example. The IoT device is required to have extremely low communication frequency and low power consumption as compared with conventional devices such as smartphones.

  The communication terminal 100 can take a connected state and an idle state as operation states. The idle state is a state in which the power consumption of the communication terminal 100 is lower than that in the connected state, and the communication terminal 100 cannot transmit data to the wireless base station 30. The connected state is a state in which connection processing is performed with the wireless base station 30 for communication connection, and the communication terminal 100 can send and receive data to and from the wireless base station 30.

  When the communication terminal 100 is in the connected state, the communication terminal 100 and the radio base station 30 perform data communication, and the radio base station 30 indicates the time elapsed from the end of the communication, which is the time indicated by the preset timer value. When it exceeds, a connection release message for causing the communication terminal 100 to transition to the idle state is transmitted to the communication terminal 100. The communication terminal 100 receiving the connection release message transits from the connected state to the idle state. As a result, the power consumption of the communication terminal 100 is reduced.

  Here, if the communication terminal 100 fails to receive the connection release message and maintains the connected state without transitioning to the idle state, the power consumption of the communication terminal 100 cannot be appropriately reduced. Even if the connection state is maintained, if the communication terminal 100 transmits data immediately after that, the power consumption due to maintaining the connection state is small. However, when the communication terminal 100 is an IoT device, the communication frequency is low, so that the connection state is maintained for a long time even if data is not transmitted, and power consumption due to the connection state being maintained. The amount increases. For example, if the communication terminal 100 is an IoT device of the type that transmits the data detected by the sensor to the wireless base station 30 once every 6 hours, the connection state is unnecessarily maintained for 6 hours. Become. In the case of conventional devices such as smartphones, communication frequency is higher than that of IoT devices, and it was difficult to recognize it as a problem because it does not consume much power due to the above problems, but in the future, as many IoT devices become widespread. , It is considered that such issues will become apparent.

  On the other hand, when the communication terminal 100 according to the present embodiment is in the connected state, it measures the time from the end of communication with the wireless base station 30 to the reception of the connection release message from the wireless base station 30, Based on the measured time, a timeout value indicating the time from the end of communication with the wireless base station 30 to the transition to the idle state is set. Then, when the communication terminal 100 is in the connected state and does not communicate with the wireless base station 30 from the end of communication with the wireless base station 30 until the time indicated by the timeout value elapses, the timeout value Transition to the idle state when the time indicated by is elapsed. As a result, even if the communication terminal 100 fails to receive the connection release message, if it does not receive the connection release message even after the time normally required to receive the connection release message elapses. At that time, it is possible to transition to the idle state, and it is possible to prevent the communication terminal 100 from unnecessarily maintaining the connected state. And thereby, it can contribute to reduction of the power consumption of the communication terminal 100.

  It is also possible that the communication terminal 100 stores the timeout value as a fixed value in advance. However, the timer value of the radio base station 30 may be changed depending on the operation, and when the timeout value is stored as a fixed value, such a change cannot be dealt with. When the timer value of the wireless base station 30 is changed by operation, it is possible that the wireless base station 30 and the communication terminal 100 negotiate to update the timeout value of the communication terminal 100. However, for example, when the communication terminal 100 is an IoT device, the number is enormous, and when the timer value of the radio base station 30 is changed, the timeout value of the IoT device by negotiating with all the IoT devices. Is difficult to change. Further, since such negotiation is not defined in the 3GPP (Third Generation Parnership Project) standard, it is practically practical to mount the negotiation function on all IoT devices and radio base stations without cost. It's difficult. On the other hand, according to the communication terminal 100 according to the present embodiment, the communication terminal 100 takes the initiative in appropriately setting the timeout value, so that the timer value of the wireless base station 30 can be flexibly changed. can do.

  FIG. 2 schematically shows an example of the flow of communication between the communication terminal 100 and the wireless base station 30. Here, an example in which the communication terminal 100 and the radio base station 30 operate according to RRC is shown. In this example, RRC Connection Release is an example of a connection release message. In addition, RRC Connected State is an example of a connected state, and RRC Idle State is an example of an idle state.

  In step (step may be abbreviated as S) 102, communication terminal 100 transmits RRC Connection Request to radio base station 30. In S104, the radio base station 30 transmits the RRC Connection Setup to the communication terminal 100. In S106, the communication terminal 100 transmits the RRC Connection Setup Complete to the radio base station 30. As a result, the communication connection between the communication terminal 100 and the wireless base station 30 is completed, and the communication terminal 100 transitions to the RRC Connected State. In addition, the wireless base station 30 manages the operation state of the communication terminal 100 as the RRC Connected State.

  In S108, data communication is performed between the communication terminal 100 and the wireless base station 30. When the data communication ends, each of the communication terminal 100 and the wireless base station 30 starts measuring the elapsed time. In response to the elapsed time reaching the time indicated by the timer value 32 preset in the wireless base station 30, the wireless base station 30 transmits the RRC Connection Release to the communication terminal 100 (S110). The radio base station 30 manages the operation state of the communication terminal 100 as if the operation state transitioned to RRC Idle State. The communication terminal 100 completes the measurement of the elapsed time and transitions to the RRC Idle State in response to receiving the RRC Connection Release.

  The communication terminal 100 indicates the time from the end of communication with the radio base station 30 to the transition to RRC Idle State, based on the measured time from the end of communication with the radio base station 30 to the reception of the RRC Connection Release. Set the timeout value. The communication terminal 100 sets, for example, a timeout value so as to indicate a time obtained by adding a predetermined time to the measured time.

  FIG. 3 schematically shows an example of the flow of communication between the communication terminal 100 and the wireless base station 30. Here, the state after the communication terminal 100 sets the timeout value 102 by the process shown in FIG. 2 and the communication terminal 100 is in the RRC Connected State will be described as a start state.

  In S202, data communication is performed between the communication terminal 100 and the wireless base station 30. When the data communication ends, each of the communication terminal 100 and the wireless base station 30 starts measuring the elapsed time. When the elapsed time has reached the time indicated by the timer value 32, the radio base station 30 transmits the RRC Connection Release to the communication terminal 100. If data communication is performed between the communication terminal 100 and the wireless base station 30 before the elapsed time reaches the time indicated by the timer value 32, the communication terminal 100 and the wireless base station 30 will When the measurement ends and the data communication ends, the measurement of the elapsed time starts again.

  In this example, the description will be continued assuming that the RRC Connection Release has not reached the communication terminal 100. Since the RRC Connection Release is not retransmitted according to the specifications of 3GPP, the RRC Connection Release is not retransmitted even if the RRC Connection Release does not reach the communication terminal 100. The communication terminal 100 transitions to the RRC Idle State when the elapsed time reaches the time indicated by the timeout value 102. By performing the processing illustrated in FIGS. 2 and 3 by the communication terminal 100, it is possible to prevent the communication terminal 100 from maintaining the RRC Connection State when the communication terminal 100 fails to receive the RRC Connection Release. ..

  FIG. 4 schematically shows an example of the flow of communication between the communication terminal 100 and the wireless base station 30. Here, a case where the timer value 32 is changed after the communication terminal 100 sets the timeout value 102 by adding the predetermined time α 106 to the measurement time 104 by the process shown in FIG. 2 will be described. Here, a case where the timer value 32 becomes long will be described.

  In S302, data communication is performed between the communication terminal 100 and the wireless base station 30. When the data communication ends, each of the communication terminal 100 and the wireless base station 30 starts measuring the elapsed time. When the elapsed time has reached the time indicated by the timer value 32, the radio base station 30 transmits an RRC Connection Release to the communication terminal 100 (S304). The communication terminal 100 completes the measurement of the elapsed time and transitions to the RRC Idle State in response to receiving the RRC Connection Release.

  As shown in FIG. 4, the communication terminal 100 receives from the radio base station 30 the RRC Connection after the measurement time 104 has elapsed from the end of the communication with the radio base station 30 and before the time indicated by the timeout value 102 has elapsed. When the Release is received, the timeout value 102 may be set based on the time from the end of communication with the radio base station 30 to the reception of the RRC Connection Release. For example, the communication terminal 100 sets the timeout value 102 so as to indicate a time obtained by adding the time α 106 to the time from the end of communication with the radio base station 30 to the reception of the RRC Connection Release. As a result, for example, when the time indicated by the timer value 32 becomes long due to the operation change in the radio base station 30, the timeout value 102 can be made long in accordance with the change.

  The communication terminal 100 may change the time α 106 as appropriate. For example, communication terminal 100 changes time α106 when a predetermined condition is satisfied. As a specific example, the communication terminal 100 considers that the timer value 32 of the RRC Connection Release has become long when the transition to the idle state due to timeout on the communication terminal 100 side has continued for a certain number (assuming that the operation has been changed), The value of the time α106 is lengthened by a predetermined time. This makes it possible to measure the time until receiving the RRC Connection Release. The fixed number may be set arbitrarily and may be changeable. Further, the predetermined time may be set arbitrarily and may be changeable.

  Further, the communication terminal 100 considers that the timer value 32 of the RRC Connection Release has become long when the frequency of transition to the idle state due to a timeout on the communication terminal 100 side is higher than a predetermined threshold (when the operation is changed, Assumed), the value of the time α 106 is lengthened by a predetermined time. This makes it possible to measure the time until receiving the RRC Connection Release. The predetermined threshold value may be set arbitrarily and may be changeable. Further, the predetermined time may be set arbitrarily and may be changeable.

  FIG. 5 schematically shows an example of the flow of communication between the communication terminal 100 and the wireless base station 30. Here, a case where the timer value 32 is changed after the communication terminal 100 sets the timeout value 102 by adding the predetermined time α 106 to the measurement time 104 by the process shown in FIG. 2 will be described. Here, a case where the timer value 32 becomes short will be described.

  In S402, data communication is performed between the communication terminal 100 and the wireless base station 30. When the data communication ends, each of the communication terminal 100 and the wireless base station 30 starts measuring the elapsed time. When the elapsed time has reached the time indicated by the timer value 32, the radio base station 30 transmits an RRC Connection Release to the communication terminal 100 (S304). The communication terminal 100 completes the measurement of the elapsed time and transitions to the RRC Idle State in response to receiving the RRC Connection Release.

  If the time from the end of communication with the wireless base station 30 to the reception of the RRC Connection Release is shorter than the measurement time 104, the communication terminal 100 may determine whether to change the timeout value 102. For example, the communication terminal 100 shortens the timeout value 102 when the time from the end of the communication with the radio base station 30 to the reception of the RRC Connection Release continues for a predetermined number of times shorter than the measurement time 104. .. For example, the communication terminal 100 times out so as to indicate a time obtained by adding a predetermined time α106 to the average time from the end of communication with the radio base station 30 until receiving the RRC Connection Release, which is measured multiple times. Set the value 102.

  Thereby, for example, when the time indicated by the timer value 32 is shortened due to the operation change in the radio base station 30, the timeout value 102 can be shortened in accordance with the change, and the communication terminal 100 shifts to the idle state. By accelerating, the power consumption of the communication terminal 100 can be reduced.

  FIG. 6 schematically shows an example of the flow of communication between the communication terminal 100 and the wireless base station 30. FIG. 6 shows a process flow when the radio base station 30 adopts the Repetition technique for extending the coverage by transmitting the same signal a plurality of times. Here, the state in which the communication terminal 100 is in the RRC Connected State will be described as the start state.

  In S502, data communication is performed between the communication terminal 100 and the wireless base station 30. When the data communication ends, each of the communication terminal 100 and the wireless base station 30 starts measuring the elapsed time. In response to the elapsed time reaching the time indicated by the timer value 32, the radio base station 30 transmits the RRC Connection Release (S504, S506, S508, S510) to the communication terminal 100.

  FIG. 6 illustrates the case where the number of Repetition is 4. An arbitrary time may be set as the transmission interval time of the Repetition transmission. Here, a case where the transmission interval time is 1 second will be described as an example. The number of Repetitions and the transmission interval time are notified to the communication terminal 100 in advance. The wireless base station 30 transmits these pieces of information to the communication terminal 100 at the time of communication connection, for example.

  The transmission of each RRC Connection Release may include information indicating how many times the Repetition transmission is performed. For example, the transmission of the RRC Connection Release in S504 includes information indicating that it is the first Reception transmission. Further, for example, the transmission of the RRC Connection Release in S506 includes information indicating that it is the second Repetition transmission. In addition, for example, the transmission of the RRC Connection Release in S508 includes information indicating that it is the third Reception transmission. In addition, for example, the transmission of the RRC Connection Release in S510 includes information indicating that it is the fourth Reception transmission.

  In the present example, the description will be continued assuming that the first and second RRC Connection Releases did not reach the communication terminal 100, and the third and fourth RRC Connection Releases reached the communication terminal 100. The communication terminal 100 completes the measurement of the elapsed time and transitions to the RRC Idle State in response to receiving the RRC Connection Release.

  The communication terminal 100 measures the time from the end of communication with the wireless base station 30 until receiving the RRC Connection Release, the number of Repetitions and the transmission interval time, and the number of times the received RRC Connection Release is the Repetition transmission. The time-out value 102 may be set based on the information indicating. For example, in the present example, since the received RRC Connection Release is the third Repetition transmission and the transmission interval time is 1 second, the communication terminal 100 subtracts 2 seconds from the measured time, thereby The time from the end of communication to the reception of the RRC connection release when the RRC connection release of the second time is received is estimated. Then, the communication terminal 100 sets the timeout value 102 based on the estimated time. For example, the communication terminal 100 sets a timeout value 102 indicating a time obtained by adding a predetermined time to the estimated time. As a result, the time indicated by the timeout value 102 can be appropriately shortened, as compared with the case where the timeout value 102 is set without considering the number of Repetitions, and the communication terminal 100 transitions to the RRC Idle State earlier and appropriately. As a result, the power consumption can be further reduced.

  The communication terminal 100 may set a plurality of timeout values 102. For example, the communication terminal 100 sets the timeout value 102 for each number of Repetitions. Further, for example, the communication terminal 100 sets the timeout value 102 for each distance from the wireless base station 30. Further, for example, the communication terminal 100 sets the timeout value 102 for each radio wave reception intensity from the radio base station 30. Further, for example, the communication terminal 100 sets the timeout value 102 for each group of the wireless base stations 30. Further, for example, the communication terminal 100 sets the timeout value 102 for each radio base station 30.

  FIG. 7 schematically shows an example of the timeout value table 161. In the timeout value table 161, the timeout value set for each number of Repetitions is registered.

  According to the timeout value table 161 shown in FIG. 7, the timeout value 102 when the repeated transmission is not performed (in FIG. 7, the number of Repetitions is 1) is 10 seconds, and when the number of Repetitions is 2, the timeout value 102. Is 11 seconds, the timeout value 102 when the number of repetitions is 3 is 12 seconds, the timeout value 102 when the number of repetitions is 4 is 13 seconds, and the timeout value 102 when the number of repetitions is 5 is 14 Seconds. As described above, the communication terminal 100 may set the longer timeout value 102 as the number of Repetitions increases.

  For example, the communication terminal 100 sets the timeout value 102 of each Repetition number based on the history of the transmission interval time of the Repetition transmission. As a specific example, when the past average of the transmission interval time of the Repetition transmission is 1 second, the communication terminal 100 increases the timeout value 102 by 1 second each time the number of Repetition increases by 1 as illustrated in FIG. 7. In addition, when the past average of the transmission intervals of the Repetition transmission is 0.5 seconds, the communication terminal 100 increases the timeout value 102 by 0.5 seconds each time the number of Repetition increases.

  The communication terminal 100 receives the number of Repetitions from the wireless base station 30 when establishing a communication connection with the wireless base station 30, for example. Then, the communication terminal 100 adopts the timeout value 102 corresponding to the received number of Repetitions as the timeout value 102 to be compared with the elapsed time from the end of communication with the wireless base station 30.

  For example, when the timer value 32 indicates 10 seconds, the number of repetitions is 4 and the transmission interval time is 1 second, the radio base station 30 receives the first RRC Connection 10 seconds after the end of the transmission with the communication terminal 100. A Release is transmitted, a second RRC Connection Release is transmitted 11 seconds later, a third RRC Connection Release is transmitted 12 seconds later, and a fourth RRC Connection Release is transmitted 13 seconds later.

  At this time, the communication terminal 100 postpones the transition to the RRC Idle State until the fourth RRC Connection Release is transmitted by using 13 seconds which is the timeout value 102 corresponding to the number of Repetition of 4. You can

  FIG. 8 schematically shows an example of the timeout value table 162. In the timeout value table 162, the timeout value set for each distance to the wireless base station 30 is registered.

  According to the timeout value table 162 shown in FIG. 8, the timeout value 102 when the distance to the wireless base station 30 is short is 10 seconds, the timeout value 102 when the distance is slightly short is 11 seconds, and the distance is standard. When the distance is a little, the timeout value 102 is 12 seconds, when the distance is a little long, the timeout value 102 is 13 seconds, and when the distance is a long distance, the timeout value 102 is 14 seconds. The distance for determining "close", "slightly close", "standard", "slightly far", or "far" may be set arbitrarily. Further, the number of stages is not limited to 5 and may be another number.

  As the distance between the communication terminal 100 and the wireless base station 30 becomes shorter, the smaller number of Repetitions tends to be set, and as the distance between the communication terminal 100 and the wireless base station 30 tends to become larger, the larger Repetition number tends to be set. By using the timeout value table 162 shown in, for example, even when the number of Repetitions set in the communication with the wireless base station 30 cannot be acquired, an appropriate timeout value can be used.

  FIG. 9 schematically shows an example of the timeout value table 163. In the timeout value table 163, the timeout value set for each radio wave reception intensity from the radio base station 30 is registered.

  According to the timeout value table 163 shown in FIG. 9, the timeout value 102 when the radio wave reception intensity is strong is 10 seconds, the timeout value 102 when the radio wave reception intensity is slightly strong is 11 seconds, and the radio wave reception intensity is standard. The timeout value 102 is 12 seconds, the timeout value 102 is 13 seconds when the radio wave reception intensity is slightly weak, and the timeout value 102 is 14 seconds when the radio wave reception intensity is weak. The radio wave reception strength for determining “strong”, “slightly strong”, “standard”, “slightly weak”, and “weak” may be set arbitrarily. Further, the number of stages is not limited to 5 and may be another number.

  FIG. 10 schematically shows an example of the timeout value table 164. In the timeout value table 164, the timeout value set for each group of wireless base stations 30 is registered.

  According to the timeout value table 164 shown in FIG. 10, the timeout value 102 for group A is 10 seconds, the timeout value 102 for group B is 11 seconds, the timeout value 102 for group C is 12 seconds, and the group D is The timeout value 102 for group E is 13 seconds and the timeout value 102 for group E is 14 seconds.

  Examples of the group of the wireless base stations 30 include a group for each area in which the wireless base station 30 is installed, a group for each vendor of the wireless base station 30, and the like. In the case of a group for each area where the wireless base station 30 is installed, the communication terminal 100 may set a shorter timeout value 102 as the average density of the communication terminals 100 in the area is higher. In an area where the communication terminals 100 are highly congested, the connection of the communication terminals 100 that are not communicating is released as early as possible and assigned to other communication terminals 100 with a high request, and a relatively short timer value 32 is set. This is because there is a tendency.

  The communication terminal 100 may set the timeout value 102 for each radio base station 30. In this case, for example, the communication terminal 100 may store a timeout value table in which the timeout value 102 is set for each base station ID of the wireless base station 30.

  FIG. 11 schematically shows an example of the functional configuration of the communication terminal 100. The communication terminal 100 includes a base station communication unit 112, a state transition unit 114, a measurement unit 120, a storage unit 130, a setting unit 140, and an information acquisition unit 150. Note that it is not essential that the communication terminal 100 has all of these configurations.

  The base station communication unit 112 communicates with the wireless base station 30. The base station communication unit 112 transmits, for example, a connection request to the wireless base station 30. As a specific example, the base station communication unit 112 transmits an RRC Connection Request to the radio base station 30.

  The base station communication unit 112 receives, for example, the setting information necessary for connection from the wireless base station 30. As a specific example, the base station communication unit 112 receives the RRC Connection Setup from the radio base station 30.

  The base station communication unit 112 transmits, for example, a completion message indicating that the setting is completed to the wireless base station 30. As a specific example, the base station communication unit 112 transmits an RRC Connection Setup Complete to the radio base station 30. In addition, the base station communication unit 112 transmits / receives various RRC messages conforming to RRC to / from the radio base station 30.

  The base station communication unit 112 also transmits and receives data to and from the radio base station 30. The base station communication unit 112 transmits / receives data to / from the wireless base station 30 when the communication terminal 100 is in the connected state.

  The state transition unit 114 transitions the operating state of the communication terminal 100. The state transition unit 114 transitions the communication terminal 100 to the connected state, for example. Further, the state transition unit 114 transitions the communication terminal 100 to the idle state, for example.

  The state transition unit 114 transitions the communication terminal 100 to the connection state when the communication connection between the communication terminal 100 and the wireless base station 30 is completed. Further, the state transition unit 114 transitions the communication terminal 100 to the idle state when it receives the connection release message from the wireless base station 30 when the communication terminal 100 is in the connected state.

  The measuring unit 120 measures the elapsed time from the end of communication with the wireless base station 30 when the communication terminal 100 is in the connected state. The measurement unit 120 may measure the time from the end of communication with the wireless base station 30 to the reception of the connection release message.

  The storage unit 130 stores various information. The storage unit 130 stores, for example, the time measured by the measuring unit 120.

  The setting unit 140 sets the timeout value 102 based on the time measured by the measuring unit 120. The setting unit 140 sets, for example, the timeout value 102 so as to indicate a time obtained by adding a predetermined time to the time measured by the measuring unit 120. The predetermined time may be arbitrarily set, for example, 1 second or 2 seconds, and may be changeable.

  As illustrated in FIG. 4, the setting unit 140 sets the timeout value 102 to indicate the time obtained by adding a predetermined time to the first time measured by the measurement unit 120, and then sets the timeout value 102. You may reset. For example, in the case where the communication terminal 100 is in the connected state, the setting unit 140, after the first time has elapsed from the end of communication with the wireless base station 30 and before the time indicated by the timeout value 102 has elapsed, the wireless base station. When the connection release message is received from the station 30, the timeout value 102 is set based on the time from the end of communication with the wireless base station 30 to the reception of the connection release message. The setting unit 140 sets the timeout value 102 to indicate, for example, a time obtained by adding a predetermined time to the time from the end of communication with the wireless base station 30 to the reception of the connection release message.

  The predetermined time may be set arbitrarily and may be changeable. The setting unit 140 may change the time when a predetermined condition is satisfied. For example, the setting unit 140 lengthens the time when a certain number of transitions to the idle state due to timeout on the communication terminal 100 side continue. The fixed number may be set arbitrarily and may be changeable. Further, the lengthening time may be set arbitrarily and may be changeable. In addition, for example, the setting unit 140 lengthens the time when the frequency of transition to the idle state due to timeout on the communication terminal 100 side is higher than a predetermined threshold. The threshold value may be set arbitrarily and may be changeable. Further, the lengthening time may be set arbitrarily and may be changeable.

  As illustrated in FIG. 5, the setting unit 140, when the communication terminal 100 is in the connected state, before the time indicated by the timeout value 102 elapses from the end of communication with the wireless base station 30. When the connection release message is received from, the timeout value 102 may be set based on the time from the end of communication with the wireless base station 30 to the reception of the connection release message. When the communication terminal 100 is in the connected state, the setting unit 140 sets the number of times the connection release message is received from the wireless base station 30 before the time indicated by the timeout value 102 has elapsed from the end of communication with the wireless base station 30. It may have a counting unit 142 for counting. Then, when the number of times counted by counting section 142 becomes equal to the predetermined number of times, setting section 140 times out based on the time from the end of communication with wireless base station 30 to the reception of the connection release message. The value 102 may be set. The predetermined number of times may be set arbitrarily and may be changeable.

  The setting unit 140 may set the timeout value 102 based on the plurality of times measured by the measuring unit 120. For example, the setting unit 140 sets the timeout value 102 based on the average of a plurality of times measured by the measuring unit 120 a plurality of times. As a specific example, the setting unit 140 sets the timeout value 102 to indicate a time obtained by adding a predetermined time to the average of the plurality of times measured by the measuring unit 120 a plurality of times.

  The storage unit 130 may store the timeout value 102 set by the setting unit 140. The storage unit 130 may store a timeout value table in which the timeout value 102 is registered for each number of Repetitions, as illustrated in FIG. 7. The storage unit 130 may store a timeout value table in which the timeout value 102 for each distance from the wireless base station 30 is registered, as illustrated in FIG. 8. The storage unit 130 may store a timeout table in which the timeout value 102 for each radio wave reception intensity is registered, as illustrated in FIG. 9. The storage unit 130 may store a timeout value table in which the timeout value 102 for each group of the wireless base station 30 is registered, as illustrated in FIG. 10. The storage unit 130 may store a timeout value table in which the timeout value 102 of each radio base station 30 is registered.

  The information acquisition unit 150 may acquire various information and store it in the storage unit 130. The information acquisition unit 150 acquires, for example, the number of Repetitions set in communication with the wireless base station 30. Further, the information acquisition unit 150 acquires, for example, the transmission interval time of the Repetition transmission. The information acquisition unit 150 acquires the number of Repetitions and the transmission interval time from the setting information received by the base station communication unit 112 from the wireless base station 30, for example.

  The information acquisition unit 150 may acquire the distance between the communication terminal 100 and the wireless base station 30. The information acquisition unit 150 receives, for example, information indicating the distance between the communication terminal 100 and the wireless base station 30 from the wireless base station 30. In addition, the information acquisition unit 150 acquires, for example, the distance between the communication terminal 100 and the wireless base station 30 measured by the communication terminal 100. The information acquisition unit 150 may be an example of a distance acquisition unit. The information acquisition unit 150 may acquire the radio wave reception intensity from the wireless base station 30 by the communication terminal 100. The information acquisition unit 150 acquires, for example, the radio wave reception intensity from the radio base station 30 measured by the communication terminal 100.

  The state transition unit 114 may transition the state of the communication terminal 100 based on the information stored in the storage unit 130. For example, the state transition unit 114 determines whether to shift the communication terminal 100 to the idle state based on the timeout value 102 stored in the storage unit 130.

  When the communication terminal 100 is in the connected state, the state transition unit 114 does not communicate with the wireless base station 30 from the end of communication with the wireless base station 30 until the time indicated by the timeout value 102 elapses. In this case, the communication terminal 100 may transition to the idle state. For example, when the communication terminal 100 is in the connected state, the state transition unit 114 releases the connection from the wireless base station 30 from the end of communication with the wireless base station 30 until the time indicated by the timeout value 102 elapses. When the message is not received, the communication terminal 100 is transited to the idle state.

  Whether the state transition unit 114 transitions the communication terminal 100 to the idle state based on the timeout value 102 acquired by the information acquisition unit 150 and corresponding to the number of Repetitions set in the communication with the wireless base station 30. May be determined. Further, the state transition unit 114 may determine whether to transition the communication terminal 100 to the idle state, based on the timeout value 102 acquired by the information acquisition unit 150 and corresponding to the distance from the wireless base station 30. .. Further, the state transition unit 114 determines whether to shift the communication terminal 100 to the idle state based on the timeout value 102 corresponding to the radio wave reception intensity from the wireless base station 30 acquired by the information acquisition unit 150. You may. Further, the state transition unit 114 may determine whether to transition the communication terminal 100 to the idle state, based on the timeout value 102 corresponding to the group to which the wireless base station 30 belongs. Further, the state transition unit 114 may determine whether to transition the communication terminal 100 to the idle state, based on the timeout value 102 corresponding to the wireless base station 30.

  FIG. 12 schematically shows an example of the hardware configuration of a computer 900 that functions as the communication terminal 100. The computer 900 according to the present embodiment includes a SoC (System on a Chip) 910, a main memory 922, a flash memory 924, an antenna 930, a sensor 940, and a USB (Universal Serial Bus) port 950.

  The SoC 910 operates based on the programs stored in the main memory 922 and the flash memory 924, and controls each unit. The antenna 930 is a so-called cellular antenna. The SoC 910 may implement various communication functions using the antenna 930. The SoC 910 may store the program received using the antenna 930 in the main memory 922 or the flash memory 924, for example.

  The SoC 910 may transmit the data detected by the sensor 940 using the antenna 930. The SoC 910 transmits, for example, the data detected by the sensor 940 to the wireless base station 30.

  The USB port 950 realizes a USB connection. The SoC 910 may receive a program used by the SoC 910 from a device or a memory connected to the USB port 950 and store the program in the main memory 922 or the flash memory 924.

  A program installed in the computer 900 and causing the computer 900 to function as the communication terminal 100 may work on the SoC 910 or the like to cause the computer 900 to function as each unit of the communication terminal 100. The information processing described in these programs is read by the computer 900, and is a specific means in which software and the various hardware resources described above cooperate with each other, that is, the measurement unit 120, the storage unit 130, and the setting unit. 140 and the information acquisition unit 150. Further, the information processing described in these programs is read by the computer 900, so that the base station communication unit 112 and the state transition which are concrete means in which software and the various hardware resources described above cooperate with each other. It may further function as part 114. Then, by implementing the calculation or processing of information according to the purpose of use of the computer 900 in the present embodiment by these specific means, the specific communication terminal 100 according to the purpose of use is constructed.

  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 apparent 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 embodiments 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 stages 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 by using “first”, “next”, and the like for convenience, it means that it is essential to carry out in this order. Not a thing.

10 communication system, 20 network, 30 wireless base station, 32 timer value, 100 communication terminal, 102 timeout value, 104 measurement time, 106 hours α, 112 base station communication unit, 114 state transition unit, 120 measurement unit, 130 storage unit , 140 setting unit, 142 counting unit, 150 information acquisition unit, 161 timeout value table, 162 timeout value table, 163 timeout value table, 164 timeout value table, 900 computer, 910 SoC, 922 main memory, 924 flash memory, 930 antenna , 940 sensor, 950 USB port

Claims (16)

A communication terminal,
When the communication terminal is in a connection state in which it is communicatively connected to a wireless base station, a measuring unit that measures the time from the end of communication with the wireless base station until receiving a connection release message from the wireless base station,
Based on the time measured by the measuring unit, a setting unit that sets a timeout value indicating the time from the end of communication with the wireless base station until the communication terminal transitions to an idle state,
A state transition unit that transitions the communication terminal to the idle state based on the timeout value. In the case where the communication terminal is in the connection state, the state transition unit did not communicate with the radio base station from the end of communication with the radio base station until the time indicated by the timeout value elapses. when shifts the communication terminal in the idle state, the communication terminal according to claim 1. The state transition unit, when the communication terminal is in the connection state, from the wireless base station to the connection release message from the end of communication with the wireless base station until the time indicated by the timeout value elapses. The communication terminal according to claim 2 , wherein the communication terminal is transitioned to the idle state when the message is not received. The setting unit, based on the plurality of the time measured by said measuring unit, sets the timeout value, the communication terminal according to any one of claims 1 to 3. The communication terminal according to claim 4 , wherein the setting unit sets the timeout value based on an average of the plurality of times measured by the measuring unit. The communication terminal according to claim 5 , wherein the setting unit sets the timeout value so as to indicate a time obtained by adding a predetermined time to an average of the plurality of times measured by the measuring unit. The setting unit is configured to set the timeout value to indicate time obtained by adding a predetermined time to the time measured by the measurement unit, the communication terminal according to any one of claims 1 to 3. The setting unit, after setting the timeout value to indicate the time adds a predetermined time to the time that has been measured by the measuring unit, when the communication terminal is in the connected state, the radio from communication end with the base station, and after the elapse of between before Symbol time measured by said measuring section, and before the time indicated by the time-out value elapses, a connection release message from the radio base station when receiving the setting the timeout value to indicate time obtained by adding the time said predetermined time to the reception of the connection-free message from communication termination of the radio base station, to claim 7 The described communication terminal. In the case where the communication terminal is in the connected state, the setting unit sends the connection release message from the wireless base station before the time indicated by the timeout value has elapsed from the end of communication with the wireless base station. The communication terminal according to any one of claims 1 to 3 , wherein when received, the timeout value is set based on the time from the end of communication with the wireless base station until the reception of the connection release message. An information acquisition unit for acquiring the number of Repetitions set in communication with the wireless base station and a transmission interval time of Repetition transmission ,
The setting unit, the time from the end of communication with the radio base station measured by the measurement unit until receiving the connection release message from the radio base station, the number of Repetition acquired by the information acquisition unit, and the The timeout value set based on the transmission interval time and the information indicating how many times the received connection release message is the Repetition transmission is stored in the storage unit in association with the Repetition number ,
Wherein the state transition unit, from the storage section for storing the timeout value corresponding to each Repetition number, obtains the timeout value corresponding to the Repetition number by the information acquiring unit has acquired, the acquired time-out value The communication terminal according to any one of claims 1 to 9 , which determines whether or not to shift the communication terminal to the idle state based on the above. A distance acquisition unit that acquires a distance between the communication terminal and the wireless base station,
The setting unit , the distance acquisition unit, the timeout value set based on the time from the end of communication with the wireless base station measured by the measuring unit until receiving the connection release message from the wireless base station Stored in the storage unit in association with the distance between the communication terminal and the wireless base station acquired by
Wherein the state transition unit, from the storage unit that stores the time-out value for each distance between the communication terminal and the radio base station obtains the timeout value corresponding to the distance the distance acquisition unit has acquired, acquires The communication terminal according to any one of claims 1 to 9 , which determines whether or not to shift the communication terminal to the idle state based on the time-out value . The setting unit, the wireless base station, the timeout value set based on the time from the end of communication with the wireless base station measured by the measuring unit until receiving the connection release message from the wireless base station. Stored in the storage unit in association with the area group where
The state transition unit stores the wireless base station to which the communication terminal is communicatively connected from the storage unit that stores the timeout value corresponding to each group of the area where the wireless base station is installed. and it has obtained the timeout value corresponding to the group of regions, based on the time-out values obtained, either determines whether to transition the communication terminal in the idle state, claims 1-9 The communication terminal according to item 1. The setting unit, the wireless base station, the timeout value set based on the time from the end of communication with the wireless base station measured by the measuring unit until receiving the connection release message from the wireless base station. Stored in the storage unit in association with the base station ID of
Wherein the state transition unit, from the storage section for storing the timeout value corresponding to each radio base station, obtains the time-out value corresponding to the radio base station said communication terminal is communicating connection, acquires The communication terminal according to any one of claims 1 to 9 , which determines whether or not to shift the communication terminal to the idle state based on the time-out value . The connection state is RRC Connected State,
The idle state is RRC Idle State,
The connection release message is an RRC Connection Release.
The communication terminal according to any one of claims 1 to 13 . The communication terminal according to any one of claims 1 to 14 , wherein the communication terminal is an IoT device. A program for causing a computer to function as the communication terminal according to any one of claims 1 to 15 .

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