Communication device, communication system, control method, and program

Abstract

To provide a communication device which can efficiently perform wireless communication.SOLUTION: A first terminal 20 is a communication device that performs wireless communication in a wireless communication band in which a limit value on the total transmission time per unit time is set, which includes: a first communication unit 21 that transmits control signals via wireless communication and receives a first notification signal, a second notification signal, or a first response signal via wireless communication; a first control unit 22 which transitions the first terminal 20 to be in a first standby state in which the first communication unit 21 waits for receiving the first response signal when the first communication unit 21 transmits the control signal; and a first setting unit 23 for setting a first continuous period in which the first standby state continues. When the first communication unit 21 transmits the control signal, the first setting unit 23 sets the first continuous period to a first predetermined period. When the first communication unit 21 receives the first notification signal or the second notification signal, before the first predetermined period has elapsed, the first continuous period is changed to a second period which is longer than the first predetermined period.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a communication device and the like. [Background technology]

[0002] Conventionally, communication devices and the like that perform wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set have been known. As an example of the communication devices and the like, Patent Document 1 discloses a wireless communication system that has first and second wireless devices that perform wireless bidirectional communication in a time division manner using a predetermined wireless channel, and each wireless device is equipped with a control unit that controls transmission so as to limit the total transmission time per predetermined unit time from the emission of radio waves to a predetermined first limit time or less. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-104026 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the wireless communication system of Patent Document 1 does not allow efficient wireless communication. For example, when wireless communication is performed in a wireless communication band in which the total transmission time limit per 3600 seconds is set to 360 seconds, the communication device sets the duration of the standby state for waiting to receive the predetermined signal to 3600 seconds, taking into consideration the possibility that the other communication device is unable to transmit the predetermined signal because the total transmission time has reached the limit. In this way, even if the other communication device is unable to transmit the predetermined signal because the total transmission time has reached the limit, the other communication device can transmit the predetermined signal during the duration, and the communication device can receive the predetermined signal. However, even if the other communication device is unable to transmit the predetermined signal not because the total transmission time has reached the limit but because of some error, the communication device must wait until 3600 seconds have passed. This is inefficient because it is not possible to determine that an error has occurred in the other communication device until 3600 seconds have passed. Thus, there is a problem of inefficient wireless communication.

[0005] The present invention has been made to solve the above-mentioned problems, and has an object to provide a communication device or the like that can efficiently perform wireless communication. [Means for solving the problem]

[0006] In order to solve the above problem, a communication device according to one embodiment of the present invention is a communication device that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set, and is equipped with: a communication unit that transmits a first signal via the wireless communication and receives a notification signal or a second signal that is a response to the first signal via the wireless communication; a control unit that, when the communication unit transmits the first signal, transitions the communication device to a standby state in which the communication unit waits for the communication unit to receive the second signal; and a setting unit that sets a duration for which the standby state will continue, wherein, when the communication unit transmits the first signal, the setting unit sets the duration to a first period, and, when the communication unit receives the notification signal before the first period has elapsed, changes the duration to a second period that is longer than the first period.

[0007] According to this, if a notification signal is received before the first period has elapsed, the duration can be changed to a second period that is longer than the first period. In this way, since the duration can be changed, wireless communication can be performed efficiently.

[0008] In addition, when the setting unit changes the duration to the second period, if the communication unit receives the second signal before the second period has elapsed, the setting unit may change the duration to the first period.

[0009] According to this, the duration period that has been changed to the second period can be changed to the first period, so that wireless communication can be performed more efficiently.

[0010] In addition, in order to solve the above problem, a communication device according to one embodiment of the present invention is a communication device that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set, and is equipped with: a communication unit that receives a first signal via the wireless communication, and, when the first signal is received, transmits a notification signal, the first signal, or a second signal that is a response to the first signal via the wireless communication; and, when the communication unit receives the first signal, a judgment unit that, for the communication device, determines whether the remaining time obtained by subtracting (1) the total transmission time in a period going back by the unit time from the present and (2) the signal transmission time required to transmit the first signal or the second signal from the limit value is shorter than the notification signal transmission time required to transmit the notification signal; and, when the judgment unit determines that the remaining time is shorter than the notification signal transmission time, the communication unit transmits the notification signal via the wireless communication, and when the judgment unit determines that the remaining time is not shorter than the notification signal transmission time, transmits the first signal or the second signal via the wireless communication.

[0011] According to this, when it is determined that the remaining time is shorter than the notification signal transmission time, the notification signal can be transmitted by wireless communication. The duration of the standby state for waiting for reception of the second signal can be changed by the notification signal. In this way, the duration can be changed, so that wireless communication can be performed efficiently.

[0012] The communication device may further include a calculation unit that calculates the notification signal transmission time based on the data amount of the notification signal, and calculates the signal transmission time based on the data amount of the first signal or the second signal.

[0013] This allows for a more accurate determination of whether the remaining time is shorter than the notification signal transmission time, thereby enabling more efficient wireless communication.

[0014] In order to solve the above problem, a communication system according to one aspect of the present invention is a communication system that performs wireless communication in a wireless communication band in which a limit value of a total transmission time per unit time is set, the communication system including a first terminal and a second terminal, wherein the first terminal has a first communication unit that transmits a control signal to the second terminal via the wireless communication and receives a first notification signal or a first response signal that is a response to the control signal from the second terminal via the wireless communication, a first control unit that, when the first communication unit transmits the control signal, transitions the first terminal to a first standby state in which the first communication unit waits for the first communication unit to receive the first response signal, and a first setting unit that sets a first duration period during which the first standby state continues, wherein the first setting unit sets the first duration period to a first predetermined period when the first communication unit transmits the control signal, and changes the first duration period to a period longer than the first predetermined period when the first communication unit receives the first notification signal before the first predetermined period has elapsed. Furthermore, the second terminal has a second communication unit that receives the control signal via the wireless communication, and when receiving the control signal, transmits the first notification signal or the first response signal via the wireless communication, and receives a second response signal that is a response to the first response signal via the wireless communication; and a first determination unit that, when the second communication unit receives the control signal, determines whether or not a first remaining time for the second terminal, which is obtained by subtracting (1) the total transmission time in a period going back by the unit time from the present and (2) a first response signal transmission time required to transmit the first response signal, from the limit value, is shorter than a first notification signal transmission time required to transmit the first notification signal, and the second communication unit transmits the first notification signal via the wireless communication when the first determination unit determines that the first remaining time is shorter than the first notification signal transmission time, and transmits the first response signal via the wireless communication when the first determination unit determines that the first remaining time is not shorter than the first notification signal transmission time.

[0015] According to this, when it is determined that the first remaining time is shorter than the first notification signal transmission time, the first notification signal can be transmitted by wireless communication, and the first duration period can be changed by the first notification signal. In this way, since the first duration period can be changed, wireless communication can be performed efficiently.

[0016] In order to solve the above problem, a communication system according to one aspect of the present invention is a communication system that performs wireless communication in a wireless communication band in which a limit value of a total transmission time per unit time is set, the communication system including: a plurality of terminals including at least a first terminal and a second terminal; and a base station; wherein the first terminal transmits a control signal to the second terminal by the wireless communication via the base station; receives from the second terminal, by the wireless communication via the base station, a first response signal that is a response to the control signal, or a second notification signal from the base station; and, upon receiving the first response signal, transmits a second response signal to the second terminal by the wireless communication via the base station; a first control unit that, when the first communication unit transmits the control signal, transitions the first terminal to a first standby state in which the first communication unit waits for the first communication unit to receive the first response signal; and a first setting unit that sets a first duration period during which the first standby state continues; and, when the first communication unit transmits the control signal, the first setting unit sets the first duration period to a first predetermined period, and the second terminal receives the control signal via the wireless communication, transmits the first response signal via the wireless communication via the base station when the control signal is received, and receives the second response signal or the second notification signal from the base station via the wireless communication via the base station; a second control unit, when the second communication unit transmits the first response signal, transitions the second terminal to a second standby state in which the second communication unit waits for the second communication unit to receive the second response signal; and a second setting unit, when the second communication unit transmits the first response signal, transitions the second terminal to a second standby state in which the second communication unit waits for the second communication unit to receive the second response signal; and a second setting unit, when the second communication unit transmits the first response signal, transitions the second terminal to a second standby state in which the second communication unit waits for the second communication unit to receive the second response signal; and a second setting unit, when the second communication unit transmits the first response signal, transitions the second terminal to a second standby state in which the second communication unit waits for the second communication unit to receive the second response signal;a third communication unit that transmits the control signal or the second response signal to the second terminal, and, when receiving the first response signal from the second terminal via the wireless communication, transmits the first response signal to the first terminal via the wireless communication; and a second determination unit that, when the third communication unit receives the control signal, the first response signal, or the second response signal, determines, for the base station, whether a second remaining time obtained by subtracting, from the limit value, (1) the total transmission time in a period going back by the unit time from the present, and (2) the signal transmission time required to transmit the control signal, the first response signal, or the second response signal, is shorter than a second notification signal transmission time required to transmit the second notification signal, wherein, when the second determination unit determines that the second remaining time is shorter than the second notification signal transmission time, the third communication unit broadcasts the second notification signal via the wireless communication, and when the second determination unit determines that the second remaining time is not shorter than the second notification signal transmission time, transmits the control signal, the first response signal, or the second response signal via the wireless communication.

[0017] According to this, when it is determined that the second remaining time is shorter than the second notification signal transmission time, the second notification signal can be broadcast via wireless communication, and the first duration period and the second duration period can be changed by the second notification signal. In this way, since the first duration period and the second duration period can be changed, wireless communication can be performed efficiently.

[0018] In addition, in order to solve the above problem, a control method according to one embodiment of the present invention is a control method for a communication device that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set, and includes a communication step of transmitting a first signal via the wireless communication and receiving a notification signal or a second signal that is a response to the first signal via the wireless communication; a control step of, if the first signal is transmitted in the communication step, transitioning the communication device to a standby state in which it waits to receive the second signal in the communication step; and a setting step of setting a duration for which the standby state will continue, wherein, in the setting step, if the first signal is transmitted in the communication step, the duration is set to a first period, and if the notification signal is received in the communication step before the first period has elapsed, the duration is changed to a second period that is longer than the first period.

[0019] According to this, if a notification signal is received before the first period has elapsed, the duration can be changed to a second period that is longer than the first period. In this way, since the duration can be changed, wireless communication can be performed efficiently.

[0020] In addition, in order to solve the above problem, a control method according to one embodiment of the present invention is a control method for a communication device that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set, and includes a communication step of receiving a first signal via the wireless communication, and, if the first signal is received, transmitting a notification signal, the first signal, or a second signal that is a response to the first signal via the wireless communication; and, if the first signal is received in the communication step, determining for the communication device whether the remaining time obtained by subtracting (1) the total transmission time in a period going back by the unit time from the present and (2) the signal transmission time required to transmit the first signal or the second signal from the limit value is shorter than the notification signal transmission time required to transmit the notification signal, and in the communication step, if it is determined in the determination step that the remaining time is shorter than the notification signal transmission time, transmitting the notification signal via the wireless communication, and if it is determined in the determination step that the remaining time is not shorter than the notification signal transmission time, transmitting the first signal or the second signal via the wireless communication.

[0021] According to this, when it is determined that the remaining time is shorter than the notification signal transmission time, the notification signal can be transmitted by wireless communication. The notification signal can change the duration of the standby state for waiting for reception of the first signal or the second signal. In this way, the duration can be changed, so wireless communication can be performed efficiently.

[0022] In order to solve the above problem, a control method according to one aspect of the present invention is a control method for a communication system that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, the communication system including a first terminal and a second terminal, and including a first communication step in which the first terminal transmits a control signal to the second terminal via the wireless communication and receives a first notification signal or a first response signal that is a response to the control signal from the second terminal via the wireless communication; a first control step in which, if the control signal is transmitted in the first communication step, the first terminal transitions to a first standby state in which the first terminal waits for reception of the first response signal in the first communication step; and a first setting step in which a first duration period for continuing the first standby state is set, wherein, in the first setting step, if the control signal is transmitted in the first communication step, the first duration period is set to a first predetermined period, and if the first notification signal is received in the first communication step before the first predetermined period has elapsed, the first duration period is set to a period longer than the first predetermined period. a second communication step of changing the period to a predetermined period, in which the second terminal receives the control signal via the wireless communication, and, if the control signal is received, transmits the first notification signal or the first response signal via the wireless communication, and receives a second response signal that is a response to the first response signal via the wireless communication; and, if the control signal is received in the second communication step, determining for the second terminal whether a first remaining time, which is obtained by subtracting (1) the total transmission time in a period going back by the unit time from the present and (2) a first response signal transmission time required to transmit the first response signal, from the limit value, is shorter than a first notification signal transmission time required to transmit the first notification signal, in which, in the second communication step, if it is determined in the first determination step that the first remaining time is shorter than the first notification signal transmission time, the first notification signal is transmitted via the wireless communication, and if it is determined in the first determination step that the first remaining time is not shorter than the first notification signal transmission time, the first response signal is transmitted via the wireless communication.

[0023] According to this, when it is determined that the first remaining time is shorter than the first notification signal transmission time, the first notification signal can be transmitted by wireless communication, and the first duration period can be changed by the first notification signal. In this way, since the first duration period can be changed, wireless communication can be performed efficiently.

[0024] In order to solve the above problem, a control method according to one aspect of the present invention is a control method for a communication system that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, the communication system including a plurality of terminals including at least a first terminal and a second terminal, and a base station, the control method including a first communication step in which the first terminal transmits a control signal to the second terminal by the wireless communication via the base station, receives from the second terminal by the wireless communication via the base station a first response signal that is a response to the control signal or a second notification signal from the base station, and, upon receiving the first response signal, transmits a second response signal to the second terminal by the wireless communication via the base station; a first control step in which, if the control signal has been transmitted in the first communication step, the first terminal transitions to a first standby state in which the first terminal waits for reception of the first response signal in the first communication step; and a first setting step in which, if the control signal has been transmitted in the first communication step, the first standby state is continued for a first duration, and in the first setting step, the first duration is set to a first duration a second communication step of the second terminal receiving the control signal by the wireless communication, transmitting the first response signal by the wireless communication via the base station when the control signal is received, and receiving the second response signal or the second notification signal from the base station by the wireless communication via the base station; a second control step of transitioning the second terminal to a second standby state in which the second terminal waits for reception of the second response signal in the second communication step when the first response signal is transmitted; and a second setting step of setting a second standby state in which the second standby state continues, wherein in the second setting step, the second duration is set to a second predetermined period when the first response signal is transmitted in the second communication step, and the second duration is changed to a period longer than the second predetermined period when the second notification signal is received in the second communication step before the second predetermined period has elapsed;a third communication step of, when receiving the control signal or the second response signal from the first terminal via the wireless communication, transmitting the control signal or the second response signal to the second terminal via the wireless communication, and, when receiving the first response signal from the second terminal via the wireless communication, transmitting the first response signal to the first terminal via the wireless communication; and, when receiving the control signal, the first response signal, or the second response signal in the third communication step, calculating, from the limit value, for the base station, (1) the total transmission time in a period going back by the unit time from the present, and (2) the time period for the control signal, the first response signal, and a second determination step of determining whether a second remaining time obtained by subtracting a signal transmission time required to transmit the control signal, the first response signal, or the second response signal is shorter than a second notification signal transmission time required to transmit the second notification signal, and in the third communication step, if it is determined in the second determination step that the second remaining time is shorter than the second notification signal transmission time, the second notification signal is broadcast via the wireless communication, and if it is determined in the second determination step that the second remaining time is not shorter than the second notification signal transmission time, the control signal, the first response signal, or the second response signal is transmitted via the wireless communication.

[0025] According to this, when it is determined that the second remaining time is shorter than the second notification signal transmission time, the second notification signal can be broadcast via wireless communication, and the first duration period and the second duration period can be changed by the second notification signal. In this way, since the first duration period and the second duration period can be changed, wireless communication can be performed efficiently.

[0026] In order to solve the above problem, a program according to one aspect of the present invention is a program that causes a computer to execute the above control method.

[0027] This provides the same effects as the above control method. [Effects of the Invention]

[0028] According to the present invention, a communication device or the like can efficiently perform wireless communication. [Brief explanation of the drawings]

[0029] [Figure 1] FIG. 1 is a block diagram illustrating a functional configuration of a communication system according to an embodiment. [Figure 2] FIG. 2 is a flowchart showing an example of the operation of the first terminal of the communication system of FIG. [Figure 3] FIG. 3 is a flowchart showing an example of the operation of the second terminal of the communication system of FIG. [Figure 4] FIG. 4 is a flowchart showing an example of the operation of step S21 in FIG. [Figure 5] FIG. 5 is a flowchart showing an example of the operation of the base station of the communication system of FIG. [Figure 6] FIG. 6 is a sequence diagram showing a first operation example of the communication system of FIG. [Figure 7] FIG. 7 is a sequence diagram showing a second operation example of the communication system of FIG. [Figure 8] FIG. 8 is a sequence diagram showing a third operation example of the communication system of FIG. [Figure 9] FIG. 9 is a sequence diagram showing a fourth operation example of the communication system of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0030] Hereinafter, the embodiments will be specifically described with reference to the drawings.

[0031] The embodiments described below each show a preferred specific example of the present invention. The numerical values, shapes, materials, components, the arrangement and connection of the components, steps, the order of steps, and the like shown in the following embodiments are merely examples and are not intended to limit the present invention.

[0032] Furthermore, among the components in the following embodiments, those not recited in the independent claims will be described as optional components that constitute more preferred embodiments. Note that the same components will be given the same reference numerals, and their description may be omitted.

[0033] (Embodiment) 1 is a block diagram showing the functional configuration of a communication system 10 according to an embodiment. The functional configuration of the communication system 10 will be described with reference to FIG.

[0034] The communication system 10 is a communication system that performs wireless communication in a wireless communication band in which a limit on the total transmission time per unit time is set. For example, wireless communication performed in a wireless communication band in which a limit on the total transmission time per unit time is set is wireless communication conforming to the IEEE 802.11ah standard. Under the Japanese Radio Law, the IEEE 802.11ah standard limits the total transmission time per unit time to 10% of the unit time. Note that the wireless communication performed by the communication system 10 is not limited to wireless communication conforming to the IEEE 802.11ah standard. As shown in FIG. 1 , the communication system 10 includes a first terminal 20, a second terminal 30, and a base station 40. Note that the communication system 10 may further include terminals other than the first terminal 20 and the second terminal 30.

[0035] First terminal 20 is an example of a communication device that performs wireless communication in a wireless communication band in which a limit value for total transmission time per unit time is set. First terminal 20 has first communication unit 21, first control unit 22, first setting unit 23, and first storage unit 24. For example, first communication unit 21 is realized by a wireless communication circuit such as an antenna and a wireless module, first control unit 22 and first setting unit 23 are realized by a processor or the like, and first storage unit 24 is realized by a memory or the like.

[0036] The first communication unit 21 transmits a control signal to the second terminal 30 by wireless communication via the base station 40. For example, the control signal is a data request signal for causing the second terminal 30 to transmit data, or a command signal for causing the second terminal 30 to perform a predetermined operation, etc. The control signal is an example of a first signal.

[0037] Furthermore, the first communication unit 21 receives a first notification signal or a first response signal that is a response to the control signal from the second terminal 30 by wireless communication via the base station 40. The first notification signal will be described later. For example, the first response signal is a signal indicating data requested by a data request signal, or a signal indicating that a control signal has been received. The first notification signal is an example of a notification signal. The first response signal is also an example of a second signal.

[0038] Furthermore, the first communication unit 21 receives a second notification signal from the base station 40. The second notification signal will be described later. The second notification signal is an example of a notification signal.

[0039] Furthermore, upon receiving the first response signal, the first communication unit 21 transmits a second response signal to the second terminal 30 by wireless communication via the base station 40. The second response signal is a response to the first response signal, and is, for example, a signal indicating that the first response signal has been received.

[0040] When the first communication unit 21 transmits the control signal, the first control unit 22 transitions the first terminal 20 to a first standby state in which the first communication unit 21 waits for reception of a first response signal. The first standby state is an example of a standby state.

[0041] The first setting unit 23 sets a first duration for which the first standby state continues. For example, the first setting unit 23 sets the first duration to a first predetermined period as an initial value of the first duration. The first duration is an example of a duration. The first predetermined period is also an example of a first period.

[0042] When the first communication unit 21 transmits a control signal, the first setting unit 23 sets the first duration period to a first predetermined period, and when the first communication unit 21 receives a first notification signal before the first predetermined period has elapsed, the first setting unit 23 changes the first duration period to a period longer than the first predetermined period. This period is an example of the second period.

[0043] Furthermore, when the first communication unit 21 transmits a control signal, the first setting unit 23 sets the first duration period to a first predetermined period, and when the first communication unit 21 receives a second notification signal before the first predetermined period has elapsed, the first setting unit 23 changes the first duration period to a period longer than the first predetermined period. This period is an example of the second period.

[0044] In addition, if the first setting unit 23 changes the first duration period to a period longer than the first predetermined period, and the first communication unit 21 receives a first response signal before that period has elapsed, the first setting unit 23 changes the first duration period to the first predetermined period.

[0045] For example, the first predetermined period is a period shorter than a unit time, and is usually set to about the period from when the first terminal 20 transmits a control signal until a first response signal is returned to the first terminal 20 without any problems. Specifically, the first predetermined period is 1 second, etc. Furthermore, for example, a period longer than the first predetermined period is a unit time, etc. Specifically, a period longer than the first predetermined period is 3600 seconds, etc. The first setting unit 23 may obtain the first predetermined period and the period longer than the first predetermined period through input by a user, etc., or may calculate them based on a unit time, etc.

[0046] The first storage unit 24 stores various information. Specifically, the first storage unit 24 stores the content indicated by the received first response signal, information indicating the first predetermined period, information indicating a period longer than the first predetermined period, information indicating a limit value, information indicating the total transmission time, and the like.

[0047] Like the first terminal, the second terminal 30 is an example of a communication device that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set. The second terminal 30 has a second communication unit 31, a second control unit 32, a second setting unit 33, a first determination unit 34, a first calculation unit 35, and a second storage unit 36. For example, the second communication unit 31 is realized by a wireless communication circuit such as an antenna and a wireless module, the second control unit 32, the second setting unit 33, the first determination unit 34, and the first calculation unit 35 are realized by a processor or the like, and the second storage unit 36 ​​is realized by a memory or the like.

[0048] The second communication unit 31 receives a control signal by wireless communication via the base station 40, and when the control signal is received, transmits a first notification signal or a first response signal by wireless communication via the base station 40. The first notification signal is a signal that is transmitted when the first remaining time (described later) is shorter than the first notification signal transmission time, and is a signal that is transmitted when the first remaining time is about to run out. The first response signal is an example of a first signal.

[0049] Furthermore, the second communication unit 31 receives a second response signal, which is a response to the first response signal, by wireless communication via the base station 40. Furthermore, the second communication unit 31 receives a second notification signal from the base station 40. The second response signal is an example of a second signal.

[0050] When the second communication unit 31 transmits the first response signal, the second control unit 32 transitions the second terminal 30 to a second standby state in which the second communication unit 31 waits for reception of the second response signal. The second standby state is an example of a standby state.

[0051] The second setting unit 33 sets a second duration for which the second standby state continues. For example, the second setting unit 33 sets the second duration to a second predetermined period as an initial value of the second duration. The second duration is an example of a duration. The second predetermined period is also an example of a first period.

[0052] The second setting unit 33 sets the second duration to a second predetermined period when the second communication unit 31 transmits the first response signal, and changes the second duration to a period longer than the second predetermined period when the second communication unit 31 receives a second notification signal from the base station 40 before the second predetermined period has elapsed. This period is an example of the second period.

[0053] In addition, if the second setting unit 33 changes the second duration period to a period longer than the second predetermined period, and the second communication unit 31 receives a second response signal via the base station 40 before the period has elapsed, the second setting unit 33 changes the second duration period to the second predetermined period.

[0054] For example, the second predetermined period is a period shorter than a unit time and is typically set to approximately the period from when the second terminal 30 transmits a first response signal until the second response signal from the first terminal 20 returns to the second terminal 30 without any interference. Specifically, the second predetermined period is 1 second, for example. Furthermore, for example, a period longer than the second predetermined period is a unit time, for example. Specifically, a period longer than the second predetermined period is 3600 seconds, for example. The second setting unit 33 may acquire the second predetermined period and the period longer than the second predetermined period through input by a user, for example, or may calculate them based on a unit time, for example. Furthermore, the second predetermined period may be the same as or different from the first predetermined period. Furthermore, the period longer than the second predetermined period may be the same as or different from the period longer than the first predetermined period.

[0055] When the second communication unit 31 receives a control signal from the first terminal 20, the first determination unit 34 determines whether the first remaining time, which is obtained by subtracting (1) the total transmission time in the period going back by a unit time from the present and (2) the first response signal transmission time required to transmit the first response signal from the limit value for the second terminal 30, is shorter than the first notification signal transmission time required to transmit the first notification signal. For example, for the second terminal 30, if the limit value is 360 seconds, the total transmission time in the period going back by a unit time from the present is 300 seconds, and the first response signal transmission time is 1 second, the first determination unit 34 subtracts 300 seconds and 1 second from 360 seconds to calculate the first remaining time as 59 seconds. The first response signal transmission time is an example of a signal transmission time. The first remaining time is also an example of a remaining time. The first notification signal transmission time is also an example of a notification signal transmission time.

[0056] The first calculation unit 35 calculates the first notification signal transmission time based on the data amount of the first notification signal, and calculates the first response signal transmission time based on the data amount of the first response signal. For example, taking the response signal transmission time as an example, in IEEE 802.11ah, when transmitting with MCS0 / number of streams 1, the data bits per symbol is 12, so the number of bits that can be transmitted per second is 27146 [symbols] × 12 = 325752 [bits]. Therefore, if the data amount is 10 Kbytes, the transmission time is 10 [Kbytes] × 1000 × 8 ÷ 325752 [bits] ≒ 0.246, or 0.246 seconds.

[0057] If the first determination unit 34 determines that the first remaining time is shorter than the first notification signal transmission time, the second communication unit 31 transmits the first notification signal instead of the first response signal via wireless communication. The first notification signal is a signal indicating that the time available for signal transmission is running out relative to the limit, leaving only time for sending the notification signal, and that a response signal cannot be transmitted. If the first response signal were transmitted instead of the notification signal in this state, even the first notification signal would not be transmitted at the next transmission timing. In other words, it is important to always leave a time margin sufficient to send the first notification signal. On the other hand, if the first determination unit 34 determines that the first remaining time is not shorter than the first notification signal transmission time, the second communication unit 31 transmits the first response signal via wireless communication. For example, the second communication unit 31 broadcasts the first notification signal.

[0058] The second storage unit 36 ​​stores various information. Specifically, the second storage unit 36 ​​stores information such as the content indicated by the received control signal, information indicating the second predetermined period, information indicating a period longer than the second predetermined period, information indicating a limit value, and information indicating the total transmission time.

[0059] In addition, since the first terminal 20 and the second terminal 30 communicate with each other using a wireless communication band in which a limit value for the total transmission time per unit time is set, the first terminal 20 has functional units equivalent to the first determination unit 34 and the first calculation unit 35 that the second terminal 30 has, and can also transmit notification signals such as those described above depending on the state, but this is omitted to simplify the explanation.

[0060] Base station 40 is an example of a communication device that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set. Base station 40 has a third communication unit 41, a second determination unit 42, a second calculation unit 43, and a third storage unit 44. For example, third communication unit 41 is realized by a wireless communication circuit such as an antenna and a wireless module, second determination unit 42 and second calculation unit 43 are realized by a processor or the like, and third storage unit 44 is realized by a memory or the like.

[0061] When the third communication unit 41 receives a control signal or a second response signal from the first terminal 20 via wireless communication, it transmits (i.e., transfers) the control signal or the second response signal to the second terminal 30 via wireless communication. Furthermore, when the third communication unit 41 receives a first response signal or a first notification signal from the second terminal 30 via wireless communication, it transmits the first response signal or the first notification signal to the first terminal 20 via wireless communication. Each of the control signal and the first response signal is an example of a first signal.

[0062] When the third communication unit 41 receives a control signal, a first response signal, a second response signal, or a first notification signal, the second determination unit 42 determines whether the second remaining time, which is calculated by subtracting (1) the total transmission time in a period going back by a unit time from the present and (2) the signal transmission time required to transmit the control signal, the first response signal, the second response signal, or the first notification signal from the limit value, is shorter than the second notification signal transmission time required to transmit the second notification signal. For example, the second determination unit 42 calculates the second remaining time in the same manner as the first determination unit 34 in the second terminal 30. The second remaining time is an example of the remaining time. The second notification signal transmission time is also an example of the notification signal transmission time.

[0063] The second calculation unit 43 calculates the second notification signal transmission time based on the data amount of the second notification signal, and calculates the signal transmission time required to transmit each signal based on the data amount of the control signal, the first response signal, the second response signal, or the first notification signal. For example, the second calculation unit 43 calculates the signal transmission time in the same manner as the first calculation unit 35.

[0064] The third communication unit 41 broadcasts a second notification signal via wireless communication when the second determination unit 42 determines that the second remaining time is shorter than the second notification signal transmission time, and transmits a control signal, a first response signal, a second response signal, or a first notification signal via wireless communication when the second determination unit 42 determines that the second remaining time is not shorter than the second notification signal transmission time. The second notification signal is a signal that is transmitted when the second remaining time is shorter than the second notification signal transmission time, and is a signal that is transmitted when the second remaining time is about to run out.

[0065] The third storage unit 44 stores various information. Specifically, the third storage unit 44 stores information indicating a limit value, information indicating a total transmission time, and the like.

[0066] Fig. 2 is a flowchart showing an example of operation of the first terminal 20 of the communication system 10 of Fig. 1. With reference to Fig. 2, an example of operation of the first terminal 20 will be described.

[0067] 2, the first communication unit 21 transmits a control signal (step S1). Specifically, the first communication unit 21 transmits the control signal to the second terminal 30 by wireless communication via the base station 40.

[0068] The first setting unit 23 sets the first duration to a first predetermined period (step S2).

[0069] The first control unit 22 transitions the first terminal 20 to a first standby state in which the first terminal 20 waits for reception of a first response signal (step S3).

[0070] The first control unit 22 determines whether or not the first notification signal or the second notification signal has been received (step S4).

[0071] If the first setting unit 23 receives the first notification signal or the second notification signal before the first predetermined period has elapsed (Yes in step S4), it changes the first duration period to a period longer than the first predetermined period (step S5).

[0072] The first control unit 22 determines whether or not the first response signal has been received (step S6).

[0073] When the first control unit 22 receives the first response signal (Yes in step S6), it sets the first duration to the first predetermined period (step S7) and transmits a second response signal (step S8). If the first duration has been changed to a period longer than the first predetermined period in step S5, the first control unit 22 changes the first duration to the first predetermined period, and if the first duration has not been changed to a period longer than the first predetermined period, it leaves the first duration set to the first predetermined period.

[0074] If the first control unit 22 has not received the first response signal (No in step S6), the first control unit 22 determines whether the first duration period has elapsed (step S9).

[0075] If the first duration period has not elapsed (No in step S9), the first control unit 22 again determines whether or not the first notification signal or the second notification signal has been received (step S4).

[0076] If the first duration period has elapsed (Yes in step S9), the first control unit 22 processes it as an error (step S10).

[0077] In this way, by setting the first duration period to a relatively short first predetermined period that allows the first response signal to be received under normal circumstances, the first response signal can be received under normal circumstances, and if an error or the like occurs, the error or the like can be detected more quickly. Furthermore, when the first notification signal or the second notification signal is received, that is, when the first remaining time of the second terminal 30 or the second remaining time of the base station 40 is about to run out, the first duration period can be changed to a period longer than the first predetermined period, so that the first response signal can be received even in this case.

[0078] Fig. 3 is a flowchart showing an example of operation of the second terminal 30 of the communication system 10 of Fig. 1. With reference to Fig. 3, an example of operation of the second terminal 30 will be described.

[0079] As shown in FIG. 3, the second communication unit 31 sets the second duration period to a second predetermined period (step S11).

[0080] The first determination unit 34 calculates the first notification signal transmission time (step S12).

[0081] The first determination unit 34 determines whether or not a control signal has been received (step S13).

[0082] If the first determination unit 34 has not received a control signal (No in step S13), the first determination unit 34 determines again whether or not a control signal has been received (step S13).

[0083] When the first determination unit 34 receives a control signal (Yes in step S13), it calculates a first response signal transmission time (step S14) and calculates a first remaining time (step S15).

[0084] The first determination unit 34 determines whether the first remaining time is shorter than the first notification signal transmission time (step S16).

[0085] If the second communication unit 31 determines that the first remaining time is shorter than the first notification signal transmission time (Yes in step S16), it transmits the first notification signal (step S17), and then the first determination unit 34 waits for the first remaining time to recover. Specifically, the second communication unit 31 calculates the first remaining time (step S18) and determines whether the first remaining time is shorter than the first notification signal transmission time (step S19), but does not send a notification signal even if it is shorter. If the second communication unit 31 then determines that the first remaining time is not shorter than the first notification signal transmission time (No in step S19), it proceeds to step S20.

[0086] If it is determined that the first remaining time is not shorter than the first notification signal transmission time (No in step S16 or No in step S19), the second communication unit 31 transmits a first response signal (step S20).

[0087] When the second terminal 30 completes the transmission of the first response signal, it performs a process of receiving a second response signal from the first terminal 20, which is the destination of the first response signal, as necessary (step S21). Thereafter, the first determination unit 34 again determines whether or not a control signal has been received (step S13).

[0088] In this way, when the first remaining time is about to run out, the first notification signal can be sent in advance, which allows the first terminal 20 to change the first duration to a longer period (step S5 in Figure 2), and even in this case, the first response signal can be received without unnecessary timeout errors occurring.

[0089] Fig. 4 is a flowchart showing an example of the operation of the reception process (step S21) of the second terminal 30 for receiving the second response signal from the first terminal 20, as shown in Fig. 3. With reference to Fig. 4, an example of the operation of step S21 will be described.

[0090] As shown in FIG. 4, the second control unit 32 transitions the second terminal 30 to a second standby state in which the second terminal 30 waits for reception of a second response signal (step S31).

[0091] The second control unit 32 determines whether or not it has received a notification signal from the first terminal 20 (as mentioned above, although not shown in Figure 1, the first terminal 20 also has a judgment unit, etc., like the second terminal 30, and sends a notification signal if the remaining time is about to run out) or a second notification signal from the base station 40 (step S32).

[0092] If the second setting unit 33 receives a notification signal from the first terminal 20 or a second notification signal from the base station 40 before the second predetermined period has elapsed (Yes in step S32), it changes the second duration period to a period longer than the second predetermined period (step S33).

[0093] The second control unit 32 determines whether or not a second response signal has been received from the first terminal 20 (step S34).

[0094] When the second control unit 32 receives a second response signal from the first terminal 20 (Yes in step S34), it sets the second duration period to the second predetermined period (step S35). If the second duration period was changed to a period longer than the second predetermined period in step S33, the second control unit 32 changes the second duration period to the second predetermined period, and if the second duration period was not changed to a period longer than the second predetermined period, the second control unit 32 leaves the second duration period set to the second predetermined period.

[0095] If the second control unit 32 has not received the second response signal from the first terminal 20 (No in step S34), the second control unit 32 determines whether the second duration period has elapsed (step S36).

[0096] If the second duration period has not elapsed (No in step S36), the second control unit 32 again determines whether or not a notification signal from the first terminal 20 or a second notification signal from the base station 40 has been received (step S32).

[0097] If the second duration period has elapsed (Yes in step S36), the second control unit 32 transmits a retransmission request (step S37).

[0098] In this way, by setting the second duration period to a relatively short second predetermined period that allows the second response signal to be received under normal circumstances, the second response signal can be received under normal circumstances, and a retransmission request can be sent earlier if the second response signal does not arrive. Also, when a notification signal from first terminal 20 or a second notification signal from base station 40 is received, that is, when the remaining time of first terminal 20 or base station 40 is about to run out, the second duration period can be changed to a period longer than the second predetermined period, so that it is possible to wait for reception of the second response signal during the second duration period without needlessly sending retransmission requests.

[0099] In addition, step S37 may be configured to perform error processing, as in step S10 in the first terminal 20.

[0100] Fig. 5 is a flowchart showing an example of operation of the base station 40 of the communication system 10 of Fig. 1. With reference to Fig. 5, an example of operation of the base station 40 will be described.

[0101] As shown in FIG. 5, the second determination unit 42 calculates the second notification signal transmission time (step S41).

[0102] The second determination unit 42 determines whether or not a control signal or the like has been received (step S42). Specifically, the second determination unit 42 determines whether or not a control signal, a first response signal, a second response signal, or a first notification signal has been received.

[0103] If the second determination unit 42 has not received a control signal or the like (No in step S42), the second determination unit 42 determines again whether or not a control signal or the like has been received (step S42).

[0104] When the second determination unit 42 receives a control signal or the like (Yes in step S42), it calculates the signal transmission time (step S43) and calculates the second remaining time (step S44). Specifically, when the second determination unit 42 receives a control signal in step S42, it calculates the signal transmission time required to transmit the control signal. When the second determination unit 42 receives a first response signal in step S42, it calculates the signal transmission time required to transmit the first response signal. When the second determination unit 42 receives a second response signal in step S42, it calculates the signal transmission time required to transmit the second response signal. When the second determination unit 42 receives a first notification signal in step S42, it calculates the signal transmission time required to transmit the first notification signal.

[0105] The second determination unit 42 determines whether the second remaining time calculated in step S44 is shorter than the second notification signal transmission time (step S45).

[0106] If the third communication unit 41 determines that the second remaining time is shorter than the second notification signal transmission time (Yes in step S45), it broadcasts the second notification signal (step S46), and the second judgment unit 42 again judges whether or not a control signal or the like has been received (step S42).

[0107] If it is determined that the second remaining time is not shorter than the second notification signal transmission time (No in step S45), the third communication unit 41 transmits a control signal or the like (step S47), and the second determination unit 42 again determines whether or not a control signal or the like has been received (step S42). Specifically, if the third communication unit 41 receives a control signal in step S42, it transmits the control signal, if the third communication unit 41 receives a first response signal in step S42, it transmits the first response signal, if the third communication unit 41 receives a second response signal in step S42, it transmits the second response signal, and if the third notification signal is received in step S42, it transmits the first notification signal.

[0108] In this way, when the second remaining time is about to run out, the second notification signal can be transmitted, so that the first duration and the second duration can be changed to longer periods. Therefore, even in this case, the control signal, the first response signal, or the second response signal can be received.

[0109] Fig. 6 is a sequence diagram showing a first operation example of the communication system 10 of Fig. 1. Fig. 6 shows an operation example in which the first remaining time is not shorter than the first notification signal transmission time and the second remaining time is not shorter than the second notification signal transmission time. The first operation example of the communication system 10 will be described with reference to Fig. 6.

[0110] As shown in FIG. 6, when the first terminal 20 transmits a control signal (step S51), the base station 40 transmits the control signal to the second terminal 30 (step S52).

[0111] If the second terminal 30 determines that the first remaining time is not shorter than the first notification signal transmission time (step S53), it transmits a first response signal (step S54).

[0112] Upon receiving the first response signal, the base station 40 transmits the first response signal to the first terminal 20 (step S55).

[0113] In this way, if each terminal and base station 40 are operating normally and there is no shortage of transmission time, first terminal 20 can quickly receive the first response signal.

[0114] Fig. 7 is a sequence diagram showing a second operation example of the communication system 10 of Fig. 1. Fig. 7 shows an operation example when an internal error occurs in the second terminal 30. The second operation example of the communication system 10 will be described with reference to Fig. 7.

[0115] As shown in FIG. 7, when the first terminal 20 transmits a control signal (step S61), the base station 40 transmits the control signal to the second terminal 30 (step S62).

[0116] The second terminal 30 receives the control signal, but does not transmit the first response signal because it is in a state where it cannot respond due to an internal error.

[0117] If the first predetermined period has elapsed, the first terminal 20 processes it as an error (step S63).

[0118] In this way, the first terminal 20 can quickly detect an error.

[0119] Fig. 8 is a sequence diagram showing a third operation example of the communication system 10 of Fig. 1. Fig. 8 shows an operation example in which the first remaining time is shorter than the first notification signal transmission time. The third operation example of the communication system 10 will be described with reference to Fig. 8.

[0120] As shown in FIG. 8, when the first terminal 20 transmits a control signal (step S71), the base station 40 transmits the control signal to the second terminal 30 (step S72).

[0121] If the second terminal 30 determines that the first remaining time is shorter than the first notification signal transmission time (step S73), it transmits the first notification signal (step S74).

[0122] Upon receiving the first notification signal, the base station 40 transmits the first notification signal to the first terminal 20 (step S75).

[0123] Upon receiving the first notification signal, the first terminal 20 changes the first duration period to a period longer than the first predetermined period (step S76).

[0124] After transmitting the first notification signal, the second terminal 30 waits until the first remaining time becomes equal to or greater than the first notification signal transmission time (step S77), and transmits the first response signal when the first remaining time becomes equal to or greater than the first notification signal transmission time (step S78).

[0125] Upon receiving the first response signal, the base station 40 transmits the first response signal to the first terminal 20 (step S79).

[0126] In this way, when the first remaining time is about to run out, the first terminal 20 changes the first duration to a period longer than the first predetermined period, so that the first response signal can be received during the first duration without being treated as an error.

[0127] Fig. 9 is a sequence diagram showing a fourth operation example of the communication system 10 of Fig. 1. Fig. 9 shows an operation example in which the first remaining time is not shorter than the first notification signal transmission time and the second remaining time is shorter than the second notification signal transmission time. The fourth operation example of the communication system 10 will be described with reference to Fig. 9.

[0128] As shown in FIG. 9, when the first terminal 20 transmits a control signal (step S81), the base station 40 determines that the second remaining time is not shorter than the second notification signal transmission time (step S82), and then transmits the control signal to the second terminal 30 (step S83).

[0129] When the second terminal 30 receives the control signal, it transmits a first response signal (step S84).

[0130] When the base station 40 determines that the second remaining time is shorter than the second notification signal transmission time (step S85), the base station 40 broadcasts the second notification signal (steps S86 and S87).

[0131] Upon receiving the second notification signal, the first terminal 20 changes the first duration period to a period longer than the first predetermined period (step S88).

[0132] Upon receiving the second notification signal, the second terminal 30 changes the second duration period to a period longer than the second predetermined period (step S89).

[0133] After broadcasting the second notification signal, the base station 40 waits until the second remaining time becomes equal to or greater than the second notification signal transmission time (step S90), and when the second remaining time becomes equal to or greater than the second notification signal transmission time, it transmits a first response signal to the first terminal 20 (step S91).

[0134] In this way, when the second remaining time is about to run out, the second terminal 30 changes the second duration period to a period longer than the second predetermined period without sending a retransmission request, so that the second response signal can be received during the second duration period without needlessly sending a retransmission request.

[0135] An example of the operation of the communication system 10 has been described above.

[0136] The communication device (first terminal 20) of this embodiment is a communication device that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set, and is equipped with a communication unit (first communication unit 21) that transmits a first signal (control signal) via wireless communication and receives a notification signal (first notification signal or second notification signal) or a second signal (first response signal) that is a response to the first signal via wireless communication, a control unit (first control unit 22) that, when the communication unit transmits the first signal, transitions the communication device to a standby state (first standby state) in which the communication unit waits for the communication unit to receive the second signal, and a setting unit (first setting unit 23) that sets a duration period (first duration period) for continuing the standby state, and when the communication unit transmits the first signal, the setting unit sets the duration period to a first period (first predetermined period), and when the communication unit receives a notification signal before the first period has elapsed, changes the duration period to a second period longer than the first period.

[0137] Furthermore, the communication device (second terminal 30) of this embodiment is a communication device that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set, and is equipped with a communication unit (second communication unit 31) that transmits a first signal (first response signal) via wireless communication and receives a notification signal (second notification signal) or a second signal (second response signal) that is a response to the first signal via wireless communication, a control unit (second control unit 32) that, when the communication unit transmits the first signal, transitions the communication device to a standby state (second standby state) in which the communication unit waits for the communication unit to receive the second signal, and a setting unit (second setting unit 33) that sets a duration (second duration) for continuing the standby state, and when the communication unit transmits the first signal, the setting unit sets the duration to a first period (second predetermined period), and when the communication unit receives a notification signal before the first period has elapsed, changes the duration to a second period that is longer than the first period.

[0138] According to this, if a notification signal is received before the first period has elapsed, the duration can be changed to a second period that is longer than the first period. In this way, since the duration can be changed, wireless communication can be performed efficiently.

[0139] Furthermore, in the communication device (first terminal 20) according to this embodiment, when the duration (first duration) is changed to the second period, if the communication unit (first communication unit 21) receives a second signal (first response signal) before the second period has elapsed, the setting unit (first setting unit 23) changes the duration to the first period (first predetermined period).

[0140] Furthermore, in the communication device (second terminal 30) according to this embodiment, when the duration (second duration) is changed to the second period, if the communication unit (second communication unit 31) receives a second signal (second response signal) before the second period has elapsed, the setting unit (second setting unit 33) changes the duration to the first period (second predetermined period).

[0141] According to this, the duration period that has been changed to the second period can be changed to the first period, so that wireless communication can be performed more efficiently.

[0142] Furthermore, the communication device (second terminal 30) of this embodiment is a communication device that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set, and is equipped with a communication unit (second communication unit 31) that receives a first signal (control signal) via wireless communication and, when the first signal is received, transmits a notification signal (first notification signal) or a second signal (first response signal) that is a response to the first signal via wireless communication, and a judgment unit (first judgment unit 34) that, when the communication unit receives the first signal, judges whether the remaining time (first remaining time) for the communication device, obtained by subtracting (1) the total transmission time in a period going back a unit time from the present and (2) the signal transmission time (first response signal transmission time) required to transmit the second signal, from the limit value, is shorter than the notification signal transmission time (first notification signal transmission time) required to transmit the notification signal, and the communication unit transmits the notification signal via wireless communication if the judgment unit judges that the remaining time is shorter than the notification signal transmission time, and transmits the second signal via wireless communication if the judgment unit judges that the remaining time is not shorter than the notification signal transmission time.

[0143] Furthermore, the communication device (base station 40) of this embodiment is a communication device that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set, and is equipped with a communication unit (third communication unit 41) that receives a first signal (control signal or first response signal) via wireless communication and, when the first signal is received, transmits a notification signal (second notification signal) or the first signal via wireless communication, and a judgment unit (second judgment unit 42) that, when the communication unit receives the first signal, judges whether the remaining time (second remaining time) for the communication device, obtained by subtracting (1) the total transmission time in a period going back a unit time from the present and (2) the signal transmission time required to transmit the first signal, from the limit value, is shorter than the notification signal transmission time (second notification signal transmission time) required to transmit the notification signal, and the communication unit transmits the notification signal via wireless communication if the judgment unit judges that the remaining time is shorter than the notification signal transmission time, and transmits the first signal via wireless communication if the judgment unit judges that the remaining time is not shorter than the notification signal transmission time.

[0144] According to this, when it is determined that the remaining time is shorter than the notification signal transmission time, the notification signal can be transmitted by wireless communication. The duration of the standby state for waiting for reception of the second signal can be changed by the notification signal. In this way, the duration can be changed, so that wireless communication can be performed efficiently.

[0145] Furthermore, the communication device (second terminal 30) according to this embodiment is provided with a calculation unit (first calculation unit 35) that calculates the notification signal transmission time (first notification signal transmission time) based on the data amount of the notification signal (first notification signal) and calculates the signal transmission time (first response signal transmission time) based on the data amount of the second signal (first response signal).

[0146] Furthermore, the communication device (base station 40) according to this embodiment is provided with a calculation unit (second calculation unit 43) that calculates the notification signal transmission time (second notification signal transmission time) based on the data amount of the notification signal (second notification signal) and calculates the signal transmission time based on the data amount of the first signal (control signal or first response signal).

[0147] This allows for a more accurate determination of whether the remaining time is shorter than the notification signal transmission time, thereby enabling more efficient wireless communication.

[0148] Furthermore, communication system 10 according to this embodiment is a communication system that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, and communication system 10 includes first terminal 20 and second terminal 30. First terminal 20 has a first communication unit 21 that transmits a control signal to second terminal 30 by wireless communication and receives a first notification signal or a first response signal that is a response to the control signal from second terminal 30 by wireless communication, a first control unit 22 that, when first communication unit 21 transmits the control signal, transitions first terminal 20 to a first standby state in which first communication unit 21 waits for reception of the first response signal, and a first setting unit 23 that sets a first duration period for continuing the first standby state, and when first communication unit 21 transmits the control signal, first setting unit 23 sets the first duration period to a first predetermined period, and when first communication unit 21 receives the first notification signal before the first predetermined period has elapsed, shortens the first duration period from the first predetermined period. The second terminal 30 has a second communication unit 31 that receives a control signal via wireless communication, and when receiving the control signal, transmits a first notification signal or a first response signal via wireless communication, and receives a second response signal that is a response to the first response signal via wireless communication; and when the second communication unit 31 receives the control signal, a first determination unit 34 that determines whether or not a first remaining time for the second terminal 30, which is obtained by subtracting (1) a total transmission time in a period going back by a unit time from the present and (2) a first response signal transmission time required to transmit the first response signal, from the limit value, is shorter than a first notification signal transmission time required to transmit the first notification signal, and when the first determination unit 34 determines that the first remaining time is shorter than the first notification signal transmission time, the second communication unit 31 transmits the first notification signal via wireless communication, and when the first determination unit 34 determines that the first remaining time is not shorter than the first notification signal transmission time, the second communication unit 31 transmits the first response signal via wireless communication.

[0149] According to this, when it is determined that the first remaining time is shorter than the first notification signal transmission time, the first notification signal can be transmitted by wireless communication, and the first duration period can be changed by the first notification signal. In this way, since the first duration period can be changed, wireless communication can be performed efficiently.

[0150] Furthermore, communication system 10 according to this embodiment is a communication system that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, and communication system 10 includes a plurality of terminals including at least first terminal 20 and second terminal 30, and base station 40, and first terminal 20 transmits a control signal to second terminal 30 by wireless communication via base station 40, receives a first response signal that is a response to the control signal from second terminal 30 by wireless communication via base station 40, or a second notification signal from base station 40, and further receives the first response signal. Then, the device has a first communication unit 21 that transmits a second response signal to the second terminal 30 by wireless communication via the base station 40, a first control unit 22 that, when the first communication unit 21 transmits a control signal, transitions the first terminal 20 to a first standby state in which the first communication unit 21 waits for reception of the first response signal, and a first setting unit 23 that sets a first duration period during which the first standby state continues, and when the first communication unit 21 transmits the control signal, the first setting unit 23 sets the first duration period to a first predetermined period, and when the first communication unit 21 receives a second notification signal before the first predetermined period has elapsed, transitions the first terminal 20 to a first standby state. The second terminal 30 includes a second communication unit 31 that receives a control signal by wireless communication, transmits a first response signal by wireless communication via the base station 40 when the control signal is received, and receives a second response signal or a second notification signal from the base station 40 by wireless communication via the base station 40; a second control unit 32 that, when the second communication unit 31 transmits the first response signal, transitions the second terminal 30 to a second standby state in which the second communication unit 31 waits for reception of the second response signal; and a second setting unit 33 that sets a second standby state for which the second standby state is to continue. the second setting unit 33 sets the second duration period to a second predetermined period when the second communication unit 31 transmits a first response signal, and changes the second duration period to a period longer than the second predetermined period when the second communication unit 31 receives a second notification signal before the second predetermined period has elapsed; the base station 40, when receiving a control signal or the second response signal from the first terminal 20 via wireless communication, transmits the control signal or the second response signal to the second terminal 30 via wireless communication; and, when receiving a first response signal from the second terminal 30 via wireless communication,The base station includes a third communication unit that transmits the first response signal to the first terminal, and a second determination unit that, when the third communication unit receives the control signal, the first response signal, or the second response signal, determines whether a second remaining time, obtained by subtracting (1) the total transmission time in a period going back by a unit time from the present and (2) the signal transmission time required to transmit the control signal, the first response signal, or the second response signal, from the limit value, is shorter than a second notification signal transmission time required to transmit the second notification signal. When the second determination unit determines that the second remaining time is shorter than the second notification signal transmission time, the third communication unit broadcasts the second notification signal by wireless communication, and when the second determination unit determines that the second remaining time is not shorter than the second notification signal transmission time, the third communication unit transmits the control signal, the first response signal, or the second response signal by wireless communication.

[0151] According to this, when it is determined that the second remaining time is shorter than the second notification signal transmission time, the second notification signal can be broadcast via wireless communication, and the first duration period and the second duration period can be changed by the second notification signal. In this way, since the first duration period and the second duration period can be changed, wireless communication can be performed efficiently.

[0152] Furthermore, the control method according to this embodiment is a control method for a communication device (first terminal 20) that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set, and includes a communication step (step S1, Yes in step S4, Yes in step S6) of transmitting a first signal (control signal) via wireless communication and receiving a notification signal (first notification signal or second notification signal) or a second signal (first response signal) that is a response to the first signal via wireless communication; a control step (step S3) of transitioning the communication device to a standby state (first standby state) in which it waits to receive the second signal in the communication step if the first signal has been transmitted in the communication step; and a setting step (steps S2, S5, step S7) of setting a duration (first duration) for continuing the standby state, in which, if the first signal has been transmitted in the communication step, the setting step sets the duration to a first period (first predetermined period), and if a notification signal is received in the communication step before the first period has elapsed, changes the duration to a second period longer than the first period.

[0153] Furthermore, the control method according to this embodiment is a control method for a communication device (second terminal 30) that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set, and includes a communication step (step S20, Yes in step S32, Yes in step S34) of transmitting a first signal (first response signal) via wireless communication and receiving a notification signal (second notification signal) or a second signal (second response signal) that is a response to the first signal via wireless communication, a control step (step S31) of transitioning the communication device to a standby state (second standby state) in which it waits to receive the second signal in the communication step if the first signal has been transmitted in the communication step, and a setting step (steps S11, S33, step S35) of setting a duration (second duration) for continuing the standby state, in which, if the first signal has been transmitted in the communication step, the setting step sets the duration to a first period (second predetermined period), and if a notification signal is received in the communication step before the first period has elapsed, the duration is changed to a second period longer than the first period.

[0154] According to this, if a notification signal is received before the first period has elapsed, the duration can be changed to a second period that is longer than the first period. In this way, since the duration can be changed, wireless communication can be performed efficiently.

[0155] Furthermore, the control method according to the present embodiment is a control method for a communication device (second terminal 30) that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, and includes a communication step of receiving a first signal (control signal) by wireless communication, and, when the first signal is received, transmitting a notification signal (first notification signal) or a second signal (first response signal) that is a response to the first signal by wireless communication (Yes in step S13, step S17, step S20); and, when the first signal is received in the communication step, calculating, for the communication device, (1) the number of unit times from the present from the limit value. and a determination step (step S16) of determining whether or not a remaining time (first remaining time) obtained by subtracting (1) the total transmission time in the period going back by 10 seconds and (2) the signal transmission time (first response signal transmission time) required to transmit the second signal is shorter than the notification signal transmission time (first notification signal transmission time) required to transmit the notification signal, and in the communication step, if it is determined in the determination step that the remaining time is shorter than the notification signal transmission time, the notification signal is transmitted by wireless communication, and if it is determined in the determination step that the remaining time is not shorter than the notification signal transmission time, the second signal is transmitted by wireless communication.

[0156] Furthermore, the control method according to this embodiment is a control method for a communication device (base station 40) that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set, and includes a communication step of receiving a first signal (control signal or first response signal) via wireless communication and, if the first signal is received, transmitting a notification signal (second notification signal) or the first signal via wireless communication (Yes in step S42, steps S46, S47); and, if the first signal is received in the communication step, a determination step (step S45) of determining whether the remaining time (second remaining time) obtained by subtracting (1) the total transmission time in a period going back a unit time from the present and (2) the signal transmission time required to transmit the first signal from the limit value is shorter than the notification signal transmission time (second notification signal transmission time) required to transmit the notification signal, and in the communication step, if it is determined in the determination step that the remaining time is shorter than the notification signal transmission time, the notification signal is transmitted via wireless communication, and if it is determined in the determination step that the remaining time is not shorter than the notification signal transmission time, the first signal is transmitted via wireless communication.

[0157] According to this, when it is determined that the remaining time is shorter than the notification signal transmission time, the notification signal can be transmitted by wireless communication. The notification signal can change the duration of the standby state for waiting for reception of the first signal or the second signal. In this way, the duration can be changed, so wireless communication can be performed efficiently.

[0158] Furthermore, the control method according to the present embodiment is a control method for a communication system 10 that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, and the communication system 10 includes a first terminal 20 and a second terminal 30, and includes a first communication step (step S1, Yes in step S4, Yes in step S6) in which the first terminal 20 transmits a control signal to the second terminal 30 by wireless communication and receives a first notification signal or a first response signal that is a response to the control signal from the second terminal 30 by wireless communication; The method includes a first control step (step S3) of transitioning the first terminal 20 to a first standby state in which the first terminal 20 waits for a first response signal to be received in the first communication step when the control signal is transmitted in the first communication step, and a first setting step (steps S2, S5, and S7) of setting a first duration period during which the first standby state is continued, and in the first setting step, when the control signal is transmitted in the first communication step, the first duration period is set to a first predetermined period, and when the first notification signal is received in the first communication step before the first predetermined period has elapsed, the first duration period is set to a first predetermined period. a second communication step (Yes in step S13, Yes in steps S17, S20, and S34) in which the second terminal 30 receives a control signal by wireless communication, transmits a first notification signal or a first response signal by wireless communication when the control signal is received, and receives a second response signal that is a response to the first response signal by wireless communication; and, when the control signal is received in the second communication step, calculates, from the limit value, (1) the total transmission time in a period going back by a unit time from the present for the second terminal 30; and (2) a first determination step (step S16) of determining whether a first remaining time obtained by subtracting the first response signal transmission time required to transmit the first response signal is shorter than the first notification signal transmission time required to transmit the first notification signal, and in the second communication step, if it is determined in the first determination step that the first remaining time is shorter than the first notification signal transmission time, the first notification signal is transmitted by wireless communication, and if it is determined in the first determination step that the first remaining time is not shorter than the first notification signal transmission time, the first response signal is transmitted by wireless communication.

[0159] According to this, when it is determined that the first remaining time is shorter than the first notification signal transmission time, the first notification signal can be transmitted by wireless communication, and the first duration period can be changed by the first notification signal. In this way, since the first duration period can be changed, wireless communication can be performed efficiently.

[0160] Furthermore, the control method according to this embodiment is a control method for a communication system 10 that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, and the communication system 10 includes a plurality of terminals including at least a first terminal 20 and a second terminal 30, and a base station 40, and the first terminal 20 transmits a control signal to the second terminal 30 by wireless communication via the base station 40, and receives a first response signal that is a response to the control signal from the second terminal 30 by wireless communication via the base station 40, or a second notification signal from the base station 40, and The method includes a first communication step (step S1, Yes in step S4, Yes in step S6, step S8) of transmitting a second response signal to the second terminal 30 by wireless communication via the base station 40 when the first response signal is received, a first control step (step S3) of transitioning the first terminal 20 to a first standby state in which the first terminal 20 waits for reception of the first response signal in the first communication step when a control signal is transmitted in the first communication step, and a first setting step (steps S2, S5, S7) of setting a first duration for which the first standby state is to continue. In this step, when a control signal is transmitted in the first communication step, the first duration is set to a first predetermined period, and when a second notification signal is received in the first communication step before the first predetermined period has elapsed, the first duration is changed to a period longer than the first predetermined period, and a second communication step (step S13) is performed in which the second terminal 30 receives a control signal by wireless communication, and when the second terminal 30 receives the control signal, transmits a first response signal by wireless communication via the base station 40, and receives a second response signal or a second notification signal from the base station 40 by wireless communication via the base station 40. and a second control step (step S31) of transitioning the second terminal 30 to a second standby state in which the second terminal 30 waits for reception of a second response signal in the second communication step if the first response signal has been transmitted in the second communication step, and a second setting step (steps S11, S33, and S35) of setting a second duration period during which the second standby state will continue, in which, in the second setting step, if the first response signal has been transmitted in the second communication step, the second duration period is set to a second predetermined period;a third communication step (Yes in step S42, steps S46, S47) of changing the second duration to a period longer than the second predetermined period if the second notification signal is received in the second communication step before the second predetermined period has elapsed, of transmitting the control signal or the second response signal to the second terminal 30 by wireless communication if the base station 40 receives a control signal or a second response signal from the first terminal 20 by wireless communication, and of transmitting the first response signal to the first terminal 20 by wireless communication if the base station 40 receives a control signal, the first response signal, or the second response signal in the third communication step; and a second determination step (step S45) of determining whether a second remaining time obtained by subtracting (1) the total transmission time in a period going back by a unit time from the present and (2) the signal transmission time required to transmit the control signal, the first response signal, or the second response signal is shorter than the second notification signal transmission time required to transmit the second notification signal, and in a third communication step, if it is determined in the second determination step that the second remaining time is shorter than the second notification signal transmission time, the second notification signal is broadcast by wireless communication, and if it is determined in the second determination step that the second remaining time is not shorter than the second notification signal transmission time, the control signal, the first response signal, or the second response signal is transmitted by wireless communication.

[0161] According to this, when it is determined that the second remaining time is shorter than the second notification signal transmission time, the second notification signal can be broadcast via wireless communication, and the first duration period and the second duration period can be changed by the second notification signal. In this way, since the first duration period and the second duration period can be changed, wireless communication can be performed efficiently.

[0162] Moreover, the program according to the present embodiment is a program that causes a computer to execute the above control method.

[0163] This provides the same effects as the above control method.

[0164] (Other embodiments) In the above-described embodiment, the first terminal 20 and the second terminal 30 perform wireless communication via the base station 40, but the present invention is not limited to this. For example, the communication system may not include a base station, and the first terminal and the second terminal may perform wireless communication without going through the base station.

[0165] In the embodiment of the present invention, when the system 10 is performing TCP communication, each terminal transmits an acknowledgement (Ack) signal to the source terminal after receiving a signal, but this is omitted in the above explanation. The effect of the present invention is that when it is predicted that the remaining time will run out, unnecessary retransmission requests can be omitted by transmitting a notification signal instead of an Ack signal to extend the duration, thereby contributing to the efficiency of communication.

[0166] The present invention can be realized not only as an apparatus or a system, but also as a method in which the processing means constituting the apparatus or system are steps, as a program that causes a computer to execute those steps, as a non-transitory recording medium such as a computer-readable CD-ROM on which the program is recorded, or as information, data, or signals that represent the program.These programs, information, data, and signals may be distributed via a communication network such as the Internet.

[0167] While the communication device and the like of the present invention have been described above based on the embodiments, the present invention is not limited to these embodiments. As long as they do not deviate from the spirit of the present invention, various modifications that a person skilled in the art can make to the present embodiments and configurations constructed by combining components of different embodiments are also included within the scope of the present invention. [Industrial Applicability]

[0168] The present invention can be used as a communication device or the like that performs wireless communication in a wireless communication band in which a limit value for the total transmission time per unit time is set. [Explanation of symbols]

[0169] 10. Communication Systems 20 Terminal 1 21 First Communications Department 22 First Control Section 23 First Setting Section 24 1st memory section 30 Terminal 2 31 Second Communications Department 32 Second Control Section 33 Second Setting Section 34 1st Judgment Section 35 First Calculation Section 36 2nd memory section 40 base station 41 Third Communications Department 42 Second Judgment Section 43 Second calculation unit 44 Third memory section

Claims

1. A communication device that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, a communication unit that transmits a first signal via the wireless communication and receives a notification signal or a second signal that is a response to the first signal via the wireless communication; a control unit that, when the communication unit transmits the first signal, transitions the communication device to a standby state in which the communication unit waits for the communication unit to receive the second signal; a setting unit that sets a duration for which the standby state is to be continued, the setting unit sets the duration to a first period when the communication unit transmits the first signal, and changes the duration to a second period longer than the first period when the communication unit receives the notification signal before the first period has elapsed. Communication equipment.

2. when the communication unit receives the second signal before the second period has elapsed, the setting unit changes the duration to the first period. The communication device according to claim 1 .

3. A communication device that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, a communication unit that receives a first signal via the wireless communication and, when the first signal is received, transmits a notification signal, the first signal, or a second signal that is a response to the first signal via the wireless communication; a determination unit that, when the communication unit receives the first signal, determines whether or not a remaining time obtained by subtracting (1) the total transmission time in a period going back by the unit time from the present and (2) a signal transmission time required to transmit the first signal or the second signal from the limit value is shorter than a notification signal transmission time required to transmit the notification signal, the communication unit transmits the notification signal via the wireless communication when the determination unit determines that the remaining time is shorter than the notification signal transmission time, and transmits the first signal or the second signal via the wireless communication when the determination unit determines that the remaining time is not shorter than the notification signal transmission time. Communication equipment.

4. a calculation unit that calculates the notification signal transmission time based on a data amount of the notification signal, and calculates the signal transmission time based on a data amount of the first signal or the second signal, The communication device according to claim 3 .

5. A communication system that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, the communication system comprises a first terminal and a second terminal; The first terminal a first communication unit that transmits a control signal to the second terminal via the wireless communication and receives a first notification signal or a first response signal that is a response to the control signal from the second terminal via the wireless communication; a first control unit that, when the first communication unit transmits the control signal, transitions the first terminal to a first standby state in which the first communication unit waits for reception of the first response signal; a first setting unit that sets a first duration during which the first standby state continues; the first setting unit sets the first duration period to a first predetermined period when the first communication unit transmits the control signal, and changes the first duration period to a period longer than the first predetermined period when the first communication unit receives the first notification signal before the first predetermined period has elapsed; The second terminal a second communication unit that receives the control signal via the wireless communication, and when receiving the control signal, transmits the first notification signal or the first response signal via the wireless communication, and receives a second response signal that is a response to the first response signal via the wireless communication; a first determination unit that, when the second communication unit receives the control signal, determines whether or not a first remaining time obtained by subtracting, from the limit value, (1) the total transmission time in a period going back by the unit time from the present and (2) a first response signal transmission time required to transmit the first response signal is shorter than a first notification signal transmission time required to transmit the first notification signal, the second communication unit transmits the first notification signal via the wireless communication when the first determination unit determines that the first remaining time is shorter than the first notification signal transmission time, and transmits the first response signal via the wireless communication when the first determination unit determines that the first remaining time is not shorter than the first notification signal transmission time. Communication system.

6. A communication system that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, the communication system includes a plurality of terminals including at least a first terminal and a second terminal, and a base station; The first terminal a first communication unit that transmits a control signal to the second terminal by the wireless communication via the base station, receives a first response signal that is a response to the control signal from the second terminal by the wireless communication via the base station, or a second notification signal from the base station, and, upon receiving the first response signal, transmits a second response signal to the second terminal by the wireless communication via the base station; a first control unit that, when the first communication unit transmits the control signal, transitions the first terminal to a first standby state in which the first communication unit waits for reception of the first response signal; a first setting unit that sets a first duration during which the first standby state continues; the first setting unit sets the first duration period to a first predetermined period when the first communication unit transmits the control signal, and changes the first duration period to a period longer than the first predetermined period when the first communication unit receives the second notification signal before the first predetermined period has elapsed; The second terminal a second communication unit that receives the control signal through the wireless communication, and when receiving the control signal, transmits the first response signal through the wireless communication via the base station, and receives the second response signal or the second notification signal from the base station through the wireless communication via the base station; a second control unit that, when the second communication unit transmits the first response signal, transitions the second terminal to a second standby state in which the second communication unit waits for reception of the second response signal; a second setting unit that sets a second duration during which the second standby state continues, the second setting unit sets the second duration period to a second predetermined period when the second communication unit transmits the first response signal, and changes the second duration period to a period longer than the second predetermined period when the second communication unit receives the second notification signal before the second predetermined period has elapsed; The base station a third communication unit that, when receiving the control signal or the second response signal from the first terminal through the wireless communication, transmits the control signal or the second response signal to the second terminal through the wireless communication, and, when receiving the first response signal from the second terminal through the wireless communication, transmits the first response signal to the first terminal through the wireless communication; a second determination unit that, when the third communication unit receives the control signal, the first response signal, or the second response signal, determines whether or not a second remaining time obtained by subtracting, from the limit value, (1) the total transmission time in a period going back by the unit time from the present, and (2) a signal transmission time required to transmit the control signal, the first response signal, or the second response signal, is shorter than a second notification signal transmission time required to transmit the second notification signal, the third communication unit broadcasts the second notification signal via the wireless communication when the second determination unit determines that the second remaining time is shorter than the second notification signal transmission time, and transmits the control signal, the first response signal, or the second response signal via the wireless communication when the second determination unit determines that the second remaining time is not shorter than the second notification signal transmission time. Communication system.

7. A method for controlling a communication device that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, comprising: a communication step of transmitting a first signal via the wireless communication and receiving a notification signal or a second signal that is a response to the first signal via the wireless communication; a control step of transitioning the communication device to a standby state in which the communication device waits for reception of the second signal in the communication step when the first signal has been transmitted in the communication step; a setting step of setting a duration for which the standby state is to be continued, In the setting step, when the first signal is transmitted in the communication step, the duration is set to a first period, and when the notification signal is received in the communication step before the first period has elapsed, the duration is changed to a second period longer than the first period. Control method.

8. A method for controlling a communication device that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, comprising: a communication step of receiving a first signal via the wireless communication, and, when the first signal is received, transmitting a notification signal, the first signal, or a second signal that is a response to the first signal via the wireless communication; a determining step of determining, when the first signal is received in the communication step, whether or not a remaining time obtained by subtracting (1) the total transmission time in a period going back by the unit time from the present and (2) a signal transmission time required to transmit the first signal or the second signal from the limit value is shorter than a notification signal transmission time required to transmit the notification signal, for the communication device; In the communication step, if it is determined in the determination step that the remaining time is shorter than the notification signal transmission time, the notification signal is transmitted by the wireless communication, and if it is determined in the determination step that the remaining time is not shorter than the notification signal transmission time, the first signal or the second signal is transmitted by the wireless communication. Control method.

9. A control method for a communication system that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, comprising: the communication system comprises a first terminal and a second terminal; The first terminal, a first communication step of transmitting a control signal to the second terminal via the wireless communication and receiving a first notification signal or a first response signal that is a response to the control signal from the second terminal via the wireless communication; a first control step of transitioning the first terminal to a first standby state in which the first terminal waits for reception of the first response signal in the first communication step when the control signal has been transmitted in the first communication step; a first setting step of setting a first duration during which the first standby state is continued, In the first setting step, when the control signal is transmitted in the first communication step, the first duration is set to a first predetermined period, and when the first notification signal is received in the first communication step before the first predetermined period has elapsed, the first duration is changed to a period longer than the first predetermined period; The second terminal, a second communication step of receiving the control signal via the wireless communication, and, when the control signal is received, transmitting the first notification signal or the first response signal via the wireless communication, and receiving a second response signal that is a response to the first response signal via the wireless communication; a first determination step of determining, when the control signal is received in the second communication step, whether or not a first remaining time obtained by subtracting, from the limit value, (1) the total transmission time in a period going back by the unit time from the present and (2) a first response signal transmission time required to transmit the first response signal is shorter than a first notification signal transmission time required to transmit the first notification signal, In the second communication step, if it is determined in the first determination step that the first remaining time is shorter than the first notification signal transmission time, the first notification signal is transmitted by the wireless communication, and if it is determined in the first determination step that the first remaining time is not shorter than the first notification signal transmission time, the first response signal is transmitted by the wireless communication. Control method.

10. A control method for a communication system that performs wireless communication in a wireless communication band in which a limit value of total transmission time per unit time is set, comprising: the communication system includes a plurality of terminals including at least a first terminal and a second terminal, and a base station; The first terminal, a first communication step of transmitting a control signal to the second terminal by the wireless communication via the base station, receiving a first response signal as a response to the control signal from the second terminal by the wireless communication via the base station or a second notification signal from the base station, and, upon receiving the first response signal, transmitting a second response signal to the second terminal by the wireless communication via the base station; a first control step of transitioning the first terminal to a first standby state in which the first terminal waits for reception of the first response signal in the first communication step when the control signal has been transmitted in the first communication step; a first setting step of setting a first duration during which the first standby state is continued, In the first setting step, when the control signal is transmitted in the first communication step, the first duration is set to a first predetermined period, and when the second notification signal is received in the first communication step before the first predetermined period has elapsed, the first duration is changed to a period longer than the first predetermined period; The second terminal, a second communication step of receiving the control signal through the wireless communication, and, when the control signal is received, transmitting the first response signal through the wireless communication via the base station, and receiving the second response signal or the second notification signal from the base station through the wireless communication via the base station; a second control step of transitioning the second terminal to a second standby state in which the second terminal waits for reception of the second response signal in the second communication step when the first response signal has been transmitted in the second communication step; a second setting step of setting a second duration during which the second standby state is continued, In the second setting step, when the first response signal is transmitted in the second communication step, the second duration is set to a second predetermined period, and when the second notification signal is received in the second communication step before the second predetermined period has elapsed, the second duration is changed to a period longer than the second predetermined period; The base station a third communication step of, when receiving the control signal or the second response signal from the first terminal via the wireless communication, transmitting the control signal or the second response signal to the second terminal via the wireless communication, and, when receiving the first response signal from the second terminal via the wireless communication, transmitting the first response signal to the first terminal via the wireless communication; a second determination step of determining, when the control signal, the first response signal, or the second response signal is received in the third communication step, whether or not a second remaining time obtained by subtracting, from the limit value, (1) the total transmission time in a period going back by the unit time from the present, and (2) a signal transmission time required to transmit the control signal, the first response signal, or the second response signal, is shorter than a second notification signal transmission time required to transmit the second notification signal, In the third communication step, if it is determined in the second determination step that the second remaining time is shorter than the second notification signal transmission time, the second notification signal is broadcast-transmitted by the wireless communication, and if it is determined in the second determination step that the second remaining time is not shorter than the second notification signal transmission time, the control signal, the first response signal, or the second response signal is transmitted by the wireless communication. Control method.

11. A program that causes a computer to execute the control method according to any one of claims 7 to 10.

Images