Communication device, communication method, and program

Abstract

To achieve power saving of a parent unit in an environment where a child unit having a power saving function belonging to the parent unit exists.SOLUTION: A communication device includes a main control unit that determines whether all child units having an associated power saving function have stopped their communication functions, and controls the communication function to be stopped during a period in which all the child units have stopped their communication functions.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a communication device, a communication method, and a program. [Background technology]

[0002] The following documents are available regarding communication systems that aim to reduce power consumption in parent and child devices.

[0003] Patent Document 1 relates to a communication system in which a base station notifies a mobile terminal of a temporary suspension period, and the mobile terminal also enters a function suspension state during the base station's temporary suspension period.

[0004] Patent Document 2 relates to a mobile router control system in which a mobile terminal transmits to a mobile router an instruction to switch the mobile router to a power saving mode, and the mobile router switches to the power saving mode in accordance with the instruction.

[0005] Patent Document 3 relates to a wireless communication device that controls data transmission to create a pause time and transitions the device to a power saving state even when the wireless channel is not free.

[0006] Patent Document 4 relates to a wireless relay device that sets its own operation mode, a first operation mode, in correspondence with a second operation mode of a wireless terminal that is recognized from an operation mode transition notification received from the wireless terminal.

[0007] Patent Document 5 relates to a wireless system in which a wireless slave device prohibits detection by intermittent carrier sense for a predetermined time determined based on the order of its own station stored in an order storage means. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] International Publication No. 2016 / 203810 [Patent Document 2] Patent Publication No. 2021-052356 [Patent Document 3] Japanese Patent Application Publication No. 2019-149677 [Patent Document 4] Japanese Patent Application Laid-Open No. 2015-046679 [Patent Document 5] Japanese Patent Application Laid-Open No. 2003-217067 Summary of the Invention [Problem to be solved by the invention]

[0009] The following analysis is given by the inventor.

[0010] In a BSS (Basic Service Set) environment where there is a parent device capable of Wi-Fi (Wireless Fidelity) communication and multiple child devices associated with it, there is an existing technology called TWT (Target Wake Time) which is a power saving function for child devices that was introduced in Wi-Fi 6 (IEEE 802.11ax).This technology allows the parent device to coordinate data communication frequency with each child device in advance and turn off the communication function of the child device when communication is not required, thereby saving power.

[0011] Meanwhile, recent wireless communication standards, such as WAN lines (5G, the fifth generation mobile communication system) and Wi-Fi lines (the aforementioned Wi-Fi 6), are both trending toward increased communication speeds and an increased number of associated devices. For battery-powered base stations like mobile routers, which are portable, it is important to ensure maximum usage time. However, assuming the implementation of these standards, power consumption is on the rise, posing a challenge for mobile routers (base stations).

[0012] The existing TWT technology aims to reduce power consumption of the handset attached to the base unit, but does not have any power-saving effect on the base unit itself.

[0013] The present invention aims to provide a communication device, a communication method, and a program that contribute to enabling power saving of a parent unit in an environment where a child unit having a power saving function belonging to the parent unit is present. [Means for solving the problem]

[0014] According to a first aspect of the present invention, there is provided a communication device including a main control unit, The main control unit determining whether or not all of the associated slave devices having a power saving function have stopped their communication functions; It is possible to provide a communication device that performs control so that the communication functions of all the slave units are stopped during a period in which the communication functions of all the slave units are stopped.

[0015] According to a second aspect of the present invention, a computer of a communication device comprises: a step of determining whether or not all of the associated slave devices having a power saving function have stopped their communication functions; A communication method can be provided that includes a step of controlling all the slave units to stop their communication functions during a period in which the communication functions of all the slave units are stopped. This method is associated with a specific machine, that is, a computer that performs the communication method.

[0016] According to a third aspect of the present invention, a computer of a communication device includes: A process of determining whether or not all of the associated slave devices having a power saving function have stopped their communication functions; It is possible to provide a program that executes a process for controlling the suspension of communication functions during the period when the communication functions of all the slave units are suspended.

[0017] These programs can be recorded on a computer-readable storage medium. The storage medium can be a non-transient medium such as a semiconductor memory, a hard disk, a magnetic recording medium, or an optical recording medium. The present invention can also be embodied as a computer program product. [Effects of the Invention]

[0018] According to the present invention, it is possible to provide a communication device, a communication method, and a program that contribute to enabling power saving of a parent unit in an environment where a child unit having a power saving function belonging to the parent unit is present. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a diagram illustrating an example of a configuration of a communication device according to an embodiment of the present invention. [Figure 2] FIG. 1 is a diagram illustrating the concept of a BSS (Basic Service Set) environment consisting of a parent device and a child device. [Figure 3] FIG. 2 is a diagram illustrating an example of a configuration of a parent device according to the first embodiment of the present invention. [Figure 4] FIG. 2 is a diagram illustrating an example of a configuration of a slave device according to the first embodiment of the present invention. [Figure 5] FIG. 1 is a diagram illustrating the concept of TWT (Target Wake Time). [Figure 6] FIG. 1 is a diagram illustrating an example of the configuration of a mobile router according to a first exemplary embodiment of the present invention. [Figure 7] FIG. 3 is a diagram illustrating an example of the operation of the mobile router and the slave device according to the first exemplary embodiment of the present invention. [Figure 8] FIG. 10 is a diagram illustrating another example of the operations of the master unit and the slave unit according to the first embodiment of the present invention for comparison with the second embodiment of the present invention. [Figure 9] FIG. 10 is a diagram illustrating an example of the operation of a parent device and a child device according to the second embodiment of the present invention. [Figure 10] FIG. 2 is a diagram showing the configuration of a computer that constitutes a main control unit of the communication device of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] First, an overview of one embodiment of the present invention will be described with reference to the drawings. Note that the reference numerals attached to the drawings in this overview are attached to each element for convenience as an example to facilitate understanding, and are not intended to limit the present invention to the illustrated form. Furthermore, connecting lines between blocks in the drawings and the like referred to in the following description include both bidirectional and unidirectional lines. Unidirectional arrows are used to schematically indicate the flow of the main signal (data) and do not exclude bidirectionality.

[0021] Fig. 1 is a diagram showing an example of the configuration of a communication device according to one embodiment of the present invention. Referring to Fig. 1, communication device (hereinafter also referred to as parent device) 10 includes a main control unit 11. The main control unit 11 determines whether all child devices having a power saving function that belong to communication device 10 have stopped their communication functions. Furthermore, the main control unit 11 controls communication device 10 to stop its communication functions while all child devices have stopped their communication functions.

[0022] The communication device 10 is a master device to which all slave devices belong, and the slave devices have a power-saving function for the slave devices, such as TWT, which allows the communication device 10 to coordinate data communication frequencies with each slave device in advance and turn off the communication function of the slave device when communication is not required. The environment in which the slave devices with power-saving functions belonging to the master device exist may be, for example, a BSS (Basic Service Set) environment in which there exists a master device capable of Wi-Fi communication and multiple slave devices belonging to it.

[0023] Therefore, according to one embodiment of the present invention, a communication device, a communication method, and a program can be provided that contribute to enabling power saving of a parent unit in an environment where a child unit having a power saving function belonging to the parent unit is present.

[0024] [First embodiment] Next, a communication device according to a first embodiment of the present invention will be described with reference to the drawings.

[0025] Fig. 2 is a diagram showing the concept of a BSS (Basic Service Set) environment consisting of a master device and slave devices. Fig. 3 is a diagram showing an example of the configuration of a master device according to the first embodiment of the present invention. Fig. 4 is a diagram showing an example of the configuration of a slave device according to the first embodiment of the present invention. Fig. 5 is a diagram showing the concept of TWT (Target Wake Time). In Figs. 2 to 5, components with the same reference numerals as those in Fig. 1 indicate the same components.

[0026] 2 is a conceptual diagram of a BSS environment assumed in the present invention and configured with a master device and slave devices. n slave devices 20A, 20B, and 20n belong to master device 10 via a Wi-Fi communication function of master device 10. This BSS environment is connected to a WAN (Wide Area Network) line 30 via a WAN communication function of master device 10, and the slave devices belonging to master device 10 can use WAN line 30 via master device 10.

[0027] The base unit 10 shown in Fig. 3 corresponds to the base unit 10 shown in Fig. 2. The slave unit 20 shown in Fig. 4 is an example of the configuration of the slave unit 20A shown in Fig. 2. Although not limited thereto, the slave units 20B and 20n will be described below assuming that they have the configuration of the slave unit 20 shown in Fig. 4.

[0028] FIG. 3 shows an example of a block diagram of base unit 10 according to the present invention, including the minimum components required for the operation of the base unit. Base unit 10 includes memory 100, main control unit 101, WAN communication module 102, antenna 103, Wi-Fi communication module 104, antenna 105, and power supply 106. Memory 100 stores necessary information. Main control unit 101 controls the entire base unit 10. WAN communication module 102 and antenna 103 are a module and antenna with a communication function that allows connection to WAN line 30 via a base station. Wi-Fi communication module 104 and antenna 105 are a module and antenna with a communication function that allows Wi-Fi connection. Power to each block of base unit 10 is supplied via power supply 106.

[0029] 4 is a diagram showing an example of a block diagram of slave device 20 according to the present invention, including the minimum components required for the slave device to operate. Slave device 20 includes memory 200, main control unit 201, Wi-Fi communication module 204, antenna 205, and power supply 206. Memory 200 stores necessary information. Main control unit 201 controls the entire slave device 20. Wi-Fi communication module 204 and antenna 205 are a module and antenna having a communication function capable of Wi-Fi connection. Power for each block of slave device 20 is supplied via power supply 206.

[0030] Next, TWT (Target Wake Time) will be explained. Fig. 5 is a diagram showing the concept of TWT. Time elapsed in the BSS environment shown in Fig. 2 is shown on time axis 400, and for simplicity, the number of associated devices will be explained as two, i.e., child devices 20A and 20B. It is assumed that master device 10, child device 20A, and child device 20B transmit Beacon 401, Beacon 402, and Beacon 403 at regular time intervals, respectively, and that the timing of the next communication between master device 10 and child device 20A, and between master device 10 and child device 20B, has been agreed upon before the start of time axis 400.

[0031] The operations of parent device 10 and child devices 20A and 20B shown in FIG. 5 are executed by main control unit 101 of parent device 10 shown in FIG. 3 and main control unit 201 shown in FIG. 4 of each of child devices 20A and 20B.

[0032] Between the base unit 10 and the slave unit 20A, in accordance with the agreement, the slave unit 20A enters a sleep time 404 in which its communication function is turned off. Thereafter, in order to release the suspension of the communication function of the slave unit 20A, a wake-up signal 405 is sent from the base unit 10 to the slave unit 20A under the control of the main control unit 101 of the base unit 10 shown in FIG. 3, thereby transitioning to a state in which communication is possible again. Similarly, between the base unit 10 and the slave unit 20B, in accordance with the agreement, the slave unit 20B enters a sleep time 406 in which its communication function is turned off. Thereafter, in order to release the suspension of the communication function of the slave unit 20B under the control of the main control unit 101 of the base unit 10 shown in FIG. 3, a wake-up signal 407 is sent from the base unit to the slave unit 20B, thereby transitioning to a state in which communication is possible again. By transitioning the slave unit to a sleep mode at a time when communication is not necessary in this way, the slave unit can achieve a power-saving effect.

[0033] In the first embodiment of the present invention, a power saving function on the parent device side is added to the power saving function for the child device by the TWT described above, thereby achieving power saving in response to an increase in the power consumption of the parent device.

[0034] FIG. 6 is a diagram showing an example of the configuration of a mobile router according to the first embodiment of the present invention. Mobile router 50 shown in FIG. 6 corresponds to base unit 10 shown in FIG. 3. FIG. 6 is a block diagram of mobile router 50 including the minimum components required for the operation of mobile router 50 as envisioned in the present invention. Mobile router 50 includes memory 500, main control unit 501, WAN communication module 502, antenna 503, Wi-Fi communication module 504, antenna 505, and power supply 506, which includes battery 507 and power supply circuit 508. Memory 500 stores necessary information. Main control unit 501 controls the entire mobile router 50. WAN communication module 502 and antenna 503 are modules and antennas with communication functions that allow connection to WAN line 30 via a base station. Wi-Fi communication module 504 and antenna 505 are modules and antennas with communication functions that allow Wi-Fi connection. Power for each block of mobile router 50 is supplied from battery 507 of power supply 506 via power supply circuit 508.

[0035] Fig. 7 is a diagram showing an example of the operation of the mobile router and the slave devices according to the first embodiment of the present invention. The operation of the mobile router 50 (master device) and the slave devices 20A and 20B shown in Fig. 7 is executed by the main control unit 501 of the mobile router 50 (master device) shown in Fig. 6 and the main control units 201 of the slave devices 20A and 20B shown in Fig. 4.

[0036] As explained in Figure 5, time axis 600 indicates the elapsed time in the BSS environment shown in Figure 2, and for simplicity, the number of devices associated with mobile router 50 is assumed to be two, handset 20A and handset 20B, with mobile router 50, handset 20A, and handset 20B respectively transmitting Beacon 601, Beacon 602, and Beacon 603 at regular time intervals. It is assumed that the agreement on the next communication timing between mobile router 50 and handset 20A, and between mobile router 50 and handset 20B, is completed before the start of time axis 600. Between mobile router 50 and each handset 20A, 20B, transitions are made to Sleep time 604 and Sleep time 606 according to that agreement, but Wake Up signal 605 and Wake Up signal 607 sent by mobile router 50 to each handset 20A, 20B cause the handset to transition to a state where communication is possible again. This is the power saving effect of the handset achieved by the existing TWT technology.

[0037] In the first embodiment of the present invention, the main control unit 501 of the mobile router 50 (parent device) determines whether or not all of the associated child devices having a power-saving function have stopped their communication functions, according to an agreement. Then, the main control unit 501 controls the mobile router 50 (parent device) to stop its communication function during the period when all of the child devices have stopped their communication functions. As a result, during the overlapping period between sleep time 604 and sleep time 606, that is, at the timing when communication is no longer required for both child devices 20A and 20B, the mobile router 50 turns off its communication function for child devices 20A and 20B associated with the mobile router 50 and transitions to sleep time 608, thereby enabling the mobile router 50 to also achieve a power-saving effect.

[0038] As described above, according to the first embodiment of the present invention, it is possible to provide a communication device, a communication method, and a program that contribute to enabling power saving in a parent device in an environment where a child device having a power saving function belonging to a mobile router (parent device) is present.

[0039] Furthermore, the first embodiment of the present invention is based on the existing technology of TWT, and turns off the communication function of the parent device when communication by the child device is not required, thereby realizing power saving effects in the parent device without restricting the communication function of the child device and regardless of the number of child devices associated with the parent device.

[0040] Furthermore, in the first embodiment of the present invention, since only the sleep time of each slave device used in the TWT is utilized, it is easy to implement a power saving function in the mobile router (master device).

[0041] Furthermore, in the first embodiment of the present invention, in conjunction with the power saving effect of the mobile router (parent device), the reduced power consumption can be allocated to other functions, such as functions that realize increased communication speeds, thereby improving communication performance without changing the usage time of the mobile router (parent device).

[0042] [Second embodiment] Next, a second embodiment of the present invention will be described with reference to the drawings. An example of the configuration of the parent device of the second embodiment of the present invention is the same as the example of the configuration of parent device 10 shown in Figure 3, so a description of that configuration will be omitted. Note that parent device 10 shown in Figure 3 may also be mobile router 50 shown in Figure 6.

[0043] The operations of base device 10 and slave devices 20A and 20B in the second embodiment of the present invention are executed by main control unit 101 of base device 10 shown in Fig. 3 and main control units 201 of slave devices 20A and 20B shown in Fig. 4. When base device 10 shown in Fig. 3 is mobile router 50 shown in Fig. 6, the operations are executed by main control unit 501 of mobile router 50.

[0044] In the second embodiment of the present invention, the end of the sleep time of the child device, that is, the time point at which the child device wakes up, is delayed to enhance the power saving effect of the parent device.

[0045] 8 is a diagram showing another example of the operation of the mobile router 50 (master device) and the slave devices of the first embodiment of the present invention for comparison with the second embodiment of the present invention. In the operation shown in FIG. 8, as in the operation shown in FIG. 7, the time elapsed in the BSS environment is indicated by a time axis 700, and for simplification, the number of devices belonging to the master device 10 is set to two, namely, slave devices 20A and 20B, and the master device 10, slave device 20A, and slave device 20B transmit Beacons 701, 702, and 703, respectively, at regular time intervals. Between the master device 10 and slave device 20A and between the master device 10 and slave device 20B, transitions are made to Sleep Time 704 and Sleep Time 706 according to the agreement, but slave devices 20A and 20B transition to a state in which they can communicate again by Wake Up Signal 705 and Wake Up Signal 707 sent by the master device 10 to each of slave devices 20A and 20B. The parent device 10 determines the sleep time 708 from the sleep time 704 and the sleep time 706, and transitions to the sleep state.

[0046] FIG. 9 is a diagram showing an example of the operation of the master device and the slave devices according to the second embodiment of the present invention. In FIG. 9, elements with the same reference numerals as those in FIG. 8 indicate the same elements. The operation of the slave device 20B is the same as that shown in FIG. 8, but in order to secure a longer sleep time 808 for the master device 10, the sleep time 804 for the slave device 20A is extended until the timing of communication resumption for the slave device 20B. Note that in FIG. 9, the beacons indicated by dashed lines indicate beacons that will not be transmitted. That is, under the control of the main control unit 101 of the master device 10 shown in FIG. 3, the later of the wake-up signals 705 and 707 shown in FIG. 8 is sent from the master device 10 to the slave device 20A, thereby transitioning the slave device 20A to a state where it is able to communicate again. That is, the main control unit 201 controls the release of the communication function of the slave device 20A to be delayed so as to coincide with the release of the communication function of the other slave device 20B to which the slave device 20A belongs. As a result, the resumption of communication by the slave device 20A is delayed by four Beacon transmissions compared to the case of Fig. 8, but the sleep time 808 of the master device 10 during the time when all the slave devices 20A and 20B are in the sleep state is extended by the amount of the delay in the resumption of communication by the slave device 20A, thereby improving the power saving effect. For example, if Beacons are transmitted at 100 millisecond intervals, the resumption of communication by the slave device 20A is delayed by 400 milliseconds, but the sleep time 808 of the master device can be secured to be 400 milliseconds longer than the sleep time 708 of the master device shown in Fig. 8.

[0047] As described above, the second embodiment of the present invention can further enhance the power saving effect of the parent unit.

[0048] [Third embodiment] Next, a third embodiment of the present invention will be described. An example of the configuration of the parent device of the third embodiment of the present invention is the same as the example of the configuration of parent device 10 shown in Fig. 3, so a description of that configuration will be omitted. Note that parent device 10 shown in Fig. 3 may be mobile router 50 shown in Fig. 6.

[0049] The operations of base device 10 and slave devices 20A and 20B in the third embodiment of the present invention are executed by main control unit 101 of base device 10 shown in Fig. 3 and main control units 201 of slave devices 20A and 20B shown in Fig. 4. When base device 10 shown in Fig. 3 is mobile router 50 shown in Fig. 6, the operations are executed by main control unit 501 of mobile router 50.

[0050] The third embodiment of the present invention is configured to enhance the power saving effect of the parent device 10 by expanding the function of turning off the parent device 10 during the sleep time.

[0051] In the first and second embodiments of the present invention, the functions used for communication with associated client devices are turned off during the sleep time of the parent device 10. In contrast, if all communication functions of the parent device 10, including WAN communication and Wi-Fi communication, are turned off, the power saving effect can be further improved. In this case, during the sleep time of the parent device, WAN communication of the client devices is disabled, and in Wi-Fi communication, the functions of sending Beacons and receiving signals from outside are also stopped, so that new client devices cannot be associated from outside the BSS environment.

[0052] As described above, the third embodiment of the present invention can further enhance the power saving effect of the parent unit.

[0053] [Fourth embodiment] Next, a fourth embodiment of the present invention will be described. An example of the configuration of the parent device of the third embodiment of the present invention is the same as the example of the configuration of parent device 10 shown in Figure 3, so a description of that configuration will be omitted. Note that parent device 10 shown in Figure 3 may also be mobile router 50 shown in Figure 6.

[0054] The fourth embodiment of the present invention is an embodiment that makes it possible to support power saving of a parent device even in the case of a child device that does not support the above-mentioned Wi-Fi6 or TWT.

[0055] The IEEE standard before Wi-Fi 6 includes a section called DTIM (Delivery Traffic Indication Message) for power saving of client devices. Unlike TWT, which adjusts the sleep time for each client device, DTIM sets the sleep time of all client devices belonging to a parent device to a common, unique value. In the first to third embodiments of the present invention, a client device compatible with the TWT function of Wi-Fi 6 was assumed. However, even if the client device does not support Wi-Fi 6 or TWT, the parent device knows the sleep time of the client device if the client device has the DTIM function implemented. Therefore, by applying the power saving method of the present invention, it is possible to put the parent device 10 into a sleep state when all client devices 20A and 20B are in a sleep state.

[0056] According to the fourth embodiment of the present invention, even when the sleep times of all the slave devices belonging to the master device are set to a common unique value, it is possible to improve the power saving effect of the master device.

[0057] Although this has been improved with TWT, when using DTIM, the sleep time is not adjusted for each handset, so there is an existing issue that some handset may not achieve the power saving effect depending on the common setting value.

[0058] In the second embodiment, a delay occurs in restarting communication with the handset, in the third embodiment, functional limitations occur due to the suspension of all communication functions, and in the fourth embodiment, there are existing issues with DTIM, and each embodiment has its own drawbacks, and depending on the extent of these drawbacks, it is expected that the actual usability of the user will be affected. Therefore, when implementing the functions of the second to fourth embodiments in a product, it is necessary to consider in advance the setting values, etc., depending on the extent to which this impact is acceptable.

[0059] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and further modifications, substitutions, and adjustments can be made without departing from the basic technical concept of the present invention. For example, the network configurations, element configurations, and message expression formats shown in the drawings are examples to aid in understanding the present invention, and the present invention is not limited to the configurations shown in these drawings. Furthermore, "A and / or B" is used to mean at least either A or B.

[0060] Furthermore, the procedures shown in the first to fourth embodiments can be realized by a program that causes a computer (9000 in FIG. 10) that functions as the communication device or main control unit of the communication device of the present invention to realize the functions of the communication device or main control unit of the communication device. Such a computer is exemplified by a configuration including a CPU (Central Processing Unit) 9010, a communication interface 9020, a memory 9030, and an auxiliary storage device 9040 in FIG. 10. That is, the CPU 9010 in FIG. 10 executes a control program for the communication device or the main control unit of the communication device, and performs an update process for each calculation parameter stored in the auxiliary storage device 9040, etc.

[0061] The memory 9030 is a RAM (Random Access Memory), a ROM (Read Only Memory), or the like.

[0062] That is, each part (processing means, function) of the communication device or the main control unit of the communication device shown in the first to fourth embodiments can be realized by a computer program that causes the processor of the computer to execute each of the above-mentioned processes using its hardware.

[0063] Finally, preferred embodiments of the present invention will be summarized. [First form] (See the communication device according to the first aspect above.) [Second form] The communication device according to the first aspect is preferably a master device to which all of the slave devices belong. [Third Form] In a communication device according to a second aspect, the parent device is preferably a mobile router. [Fourth Form] In a first aspect of the communication device, the main control unit preferably delays the release of the suspension of the communication function of the slave device so as to coincide with the release of the communication function of the other slave devices belonging to the slave device. [Fifth Form] In a communication device according to a first aspect, it is preferable that the main control unit controls the device to stop functions other than the communication function in addition to stopping the communication function. [Sixth Form] In the communication device according to the first aspect, it is preferable that the period during which the communication functions of all the slave devices are stopped is the same period. [7th form] (See the second perspective communication method above) [8th form] (See the third perspective program above) The seventh and eighth forms can be expanded to the second to sixth forms in the same way as the first form.

[0064] The disclosures of the above-cited patent documents are incorporated herein by reference. Modifications and adjustments of the embodiments and examples are possible within the scope of the entire disclosure of the present invention (including the claims), and further based on the basic technical concept thereof. Furthermore, various combinations and selections of the various disclosed elements (including each element of each claim, each element of each embodiment or example, each element of each drawing, etc.) are possible within the scope of the disclosure of the present invention. In other words, the present invention naturally embraces various modifications and alterations that would be possible by a person skilled in the art in accordance with the entire disclosure and technical concept, including the claims. In particular, with regard to the numerical ranges set forth herein, any numerical value or subrange within the range should be construed as specifically set forth, even if not otherwise specified. Furthermore, the disclosures of the above-cited documents, when used in part or in whole in combination with the disclosures herein as part of the disclosure of the present invention, in accordance with the spirit of the present invention, are also deemed to be included in the disclosures of this application. [Explanation of symbols]

[0065] 10. Communication device (parent unit) 11 Main control unit 20, 20A, 20B, 20n handset 30 WAN lines 50 Mobile Router 100, 200, 500 memory 101, 201, 501 Main control unit 102, 502 WAN communication module 103, 105, 205, 503, 505 Antennas 104, 204, 504 Wi-Fi communication modules 106, 206, 506 power supply 400, 600, 700 time scales 401, 402, 403, 601, 602, 603, 701, 702, 703 Beacon 404, 406, 604, 606, 608, 704, 706, 708, 804, 808 Sleep time 405, 407, 605, 607, 705, 707 Wake Up signal 507 Battery 508 Power supply circuit 9000 computers 9010 CPU 9020 Communication Interface 9030 Memory 9040 Auxiliary storage device

Claims

1. A communication device including a main control unit, The main control unit determining whether or not all of the associated slave devices having a power saving function have stopped their communication functions; A communication device that controls so as to stop a communication function during a period in which the communication function of all the slave devices is stopped, The main control unit delays the release of the communication function of the slave device so as to coincide with the release of the communication function of other slave devices belonging to the slave device.

2. The communication device according to claim 1 , wherein all of the slave devices belong to a master device.

3. The communication device according to claim 2 , wherein the parent device is a mobile router.

4. The communication device according to claim 1 , wherein the main control unit controls to stop functions other than the communication function in addition to stopping the communication function.

5. The computer of the communication device a step of determining whether or not all of the associated slave devices having a power saving function have stopped their communication functions; A communication method including a step of controlling all of the slave devices to stop their communication functions during a period in which the communication functions of the slave devices are stopped, A communication method comprising a step of delaying the release of the suspension of the communication function of the slave device so as to coincide with the release of the communication function of other slave devices to which the slave device belongs.

6. The computer of the communication device A process of determining whether or not all of the associated slave devices having a power saving function have stopped their communication functions; A program for executing a process of controlling the suspension of communication functions during a period in which the communication functions of all the slave devices are suspended, A program that causes the computer to execute a process of delaying the release of the suspension of the communication function of the slave device so as to coincide with the release of the communication function of other slave devices belonging to the slave device.

Images