JP2014165671A - Mobile communication system, center device, control method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently extend a continuation operation time of a base station device operated by power charged in a secondary battery at power stoppage.SOLUTION: A mobile communication system includes: a plurality of base station devices that receive power supply from a secondary battery at power stoppage to perform radio communication with mobile terminals in a communication area; and a center device that performs control processing to transmit an instruction to reduce transmission power to a first base station device that receives the power supply from the secondary battery at the power stoppage, on condition that the communication area of the first base station device overlaps with the communication area of a second base station device. Thus, by the initiative of the center device, power consumption of the first base station device is controlled, so that the continuation operation time thereof can be extended efficiently.

Description

  The present invention relates to a mobile communication system having a plurality of base station devices that receive power from a storage battery and perform wireless communication with a mobile terminal in a communication area in the event of a power failure, a center device included in the system, and a control method for the base station device And a program of the center device.

  In a mobile communication system, a base station apparatus that performs wireless communication with a mobile terminal operates with power supplied from a commercial AC power supply. However, UPS (Uninterruptible Power Supply) is used in preparation for a power failure caused by a disaster or accident. ) And so on. The base station apparatus normally performs an intended operation with an AC power supply and charges a storage battery of a backup power supply with the AC power supply, and obtains power supply from the storage battery of the backup power supply during a power failure. By doing so, the base station apparatus can continue to operate even during a power failure.

  In the above system, the time during which the base station apparatus can continuously operate in the event of a power failure is determined according to the amount of charge and the power consumption of the base station apparatus, and a method for extending the continuous operation time has been proposed. For example, Patent Document 1 describes a method in which a control unit in a base station apparatus controls power consumption by controlling a modulation scheme and transmission output according to the traffic amount of the base station.

JP 2005-252370 A

  However, the method of Patent Document 1 is for each base station apparatus to control power consumption, and there is room for improvement in effectively extending the continuous operation time of the entire mobile communication system.

  An object of the present invention is to provide a mobile communication system, a center apparatus, a control method, and a program capable of efficiently extending the continuous operation time of a base station apparatus that operates by charging power of a storage battery at the time of a power failure. It is in.

  In order to solve the above problems, a mobile communication system according to one aspect of the present invention includes a plurality of base station apparatuses that receive power supply from a storage battery during a power failure and perform wireless communication with a mobile terminal in a communication area, and the storage battery during a power failure. Control processing for sending an instruction to reduce the transmission output to the first base station apparatus receiving power supply from the mobile station on condition that the communication area of the first base station apparatus overlaps the communication area of the second base station apparatus And a center device for performing

  When the communication areas of the first and second base station apparatuses do not overlap, the center apparatus performs the control process after sending an instruction to increase the transmission output to the second base station apparatus. Alternatively, the center device may be configured on the condition that the communication traffic of the first base station device is less than a predetermined value even if the communication areas of the first and second base station devices do not overlap. Perform control processing. Moreover, the transmission output with respect to the storage amount of the storage battery in the first base station apparatus may be larger than the transmission output with respect to the storage amount of the storage battery in the second base station apparatus.

  The center device of the mobile communication system according to another aspect receives a power supply from a storage battery at the time of a power failure, and communicates with a plurality of base station devices that perform wireless communication with a mobile terminal in a communication area, and at the time of a power failure An instruction to reduce the transmission output is sent to the first base station apparatus that receives power supply from the storage battery on condition that the communication area of the first base station apparatus overlaps with the communication area of the second base station apparatus. And a control unit that performs control processing.

  When the communication areas of the first and second base station devices do not overlap, the control unit performs the control process after sending an instruction to increase the transmission output to the second base station device. Alternatively, the control unit is configured on the condition that the communication traffic of the first base station device is less than a predetermined value even when the communication areas of the first and second base station devices do not overlap. Perform control processing. Moreover, the transmission output with respect to the storage amount of the storage battery in the first base station apparatus may be larger than the transmission output with respect to the storage amount of the storage battery in the second base station apparatus.

  As described above, the solution of the present invention has been described as a system or apparatus. However, the present invention can also be realized as a method, a program, and a storage medium that records the program. It should be understood that these ranges are also included. Note that each step of the method or program uses an arithmetic processing unit such as a CPU or a DSP as necessary in data processing, and the input data, processed / generated data, etc. are stored in an HDD, memory, etc. Is stored in the storage device.

  For example, a control method according to another aspect is a control method for a plurality of base station apparatuses that receive power from a storage battery and perform wireless communication with a mobile terminal in a communication area at the time of a power failure, and supply power from the storage battery at the time of a power failure The receiving first base station apparatus reduces the transmission output on condition that the communication area of the first base station apparatus overlaps with the communication area of the second base station apparatus.

  Furthermore, a program according to another aspect that implements the present invention as a program is a processor of a center apparatus that communicates with a plurality of base station apparatuses that receive power from a storage battery and perform wireless communication with a mobile terminal in a communication area in the event of a power failure. In the first base station apparatus that receives power supply from the storage battery during a power failure, the transmission output is reduced on condition that the communication area of the first base station apparatus overlaps with the communication area of the second base station apparatus. A control process for sending an instruction is executed.

  According to the embodiment of the present invention, it is possible to efficiently extend the continuous operation time of the base station that operates with the charging power of the storage battery during a power failure.

It is a block diagram of a mobile communication system. It is a figure which shows the example of the operation | movement condition of a base station apparatus. It is a figure which shows the communication area of a base station apparatus. It is a flowchart figure which shows the operation | movement procedure of a mobile communication system. It is a flowchart figure which shows the operation | movement procedure of a mobile communication system. It is a flowchart figure which shows the operation | movement procedure of a mobile communication system. It is a flowchart figure which shows the operation | movement procedure of a mobile communication system.

  Embodiments of the present invention will be described below.

  FIG. 1 is a block diagram of a mobile communication system in the present embodiment. The mobile communication system 1 is a system that provides a wireless entrance line of a mobile phone or a personal handy-phone system (PHS), and is connected to the center device 11 via a communication network 10 via an optical line, a metal line, or the like. A plurality of base station devices 12 connected to the center device 11 and a mobile terminal 15 such as a mobile phone or a PHS phone that performs radio communication with the base station device 12 are provided. The base station apparatus 12 is connected to the center apparatus 11 and other base station apparatuses 12 via the communication network 10 so as to be able to perform data communication, and relays communication between the mobile terminals 15. Moreover, the base station apparatus 12 has a standby power source 129 having a storage battery, operates normally with supply of commercial AC power, and continuously operates with power supply from the storage battery of the standby power source 129 during a power failure. To do.

  The center device 11 includes a control unit 110, a storage unit 112, a network interface 114, an input interface 116, and an output interface 118. The center device 11 is an information processing device such as a personal computer, for example. Control unit 110 is a processor such as a CPU (Central Processing Unit). The storage unit 112 is a memory device including, for example, SRAM (Static RAM) and DRAM (Dynamic RAM). The control unit 110 operates according to a control program stored in the storage unit 112 and controls the operation of the center apparatus 11 in an integrated manner. Further, the control unit 110 is connected to the communication network 10 via the network interface 114 so that data communication is possible. Further, the control unit 110 receives input from the input unit via the input interface 116, and outputs data to the output device via the output interface. The operation of the center device 11 in the following description is the operation of the control unit 110 based on the control program.

  The base station apparatus 12 includes a control unit 120, a wireless communication unit 124, a power supply control unit 125, a network interface 126, a power supply interface 128, and a standby power supply 129. The standby power supply 129 may be provided externally to the base station apparatus 12 or may be built in. The control unit 120 is, for example, a microcomputer or an application specific integrated circuit (ASIC). The control unit 120 performs base station operations such as circuit switching and packet processing, and control processing such as transmission output increase / decrease described later. The operation of the base station apparatus 12 in the following description is the operation of the control unit 112 that operates based on a control program stored in a built-in or external memory device. The wireless communication unit 124 modulates and demodulates the data signal and performs wireless communication with the mobile terminal 15. The network interface 126 connects the control unit 120 and the communication network 10 so that data communication is possible. The power interface 128 receives power from the standby power source 129 and supplies power to the control unit 120, the wireless communication unit 124, the power control unit 125, and the network interface 126. The standby power source 129 is, for example, a UPS (Uninterruptible Power Supply) provided with a storage battery, and normally charges the storage battery with an AC power source and outputs the AC power source to the power interface 128. When the AC power supply fails, the standby power supply 129 discharges the storage battery and outputs the power to the power supply interface 128. In this way, the base station device 12 operates by receiving the power of the AC power supply during normal times and the charging power of the storage battery of the standby power supply 129 during a power failure.

  In this embodiment, at the time of a power failure of the base station device 12, the center device 11 reduces the power consumption of each base station device 12 based on the state of the communication area between the base station devices 12 and the operation status of each base station device 12. Control.

  FIG. 2 shows an example of the operation status of each base station apparatus 12. The center device 11 stores a data table for the operation status as shown in FIG. The operation status table 2 includes, for example, “base station ID”, “maximum transmission output that can be transmitted”, “transmission output during operation”, “corresponding modulation schemes” for each of the four base station apparatuses 12A to 12D. ”,“ Modulation method in operation ”,“ Power supply state ”,“ Remaining power storage ”,“ Average power consumption ”,“ Exchange time ”. Here, as the “power supply state” of the base station apparatuses 12A to 12D, a value “AC power supply” indicating power supply from the AC power supply is stored. The “exchange time” stores the time until the storage battery of the standby power source 129 of each base station apparatus is replaced by regular maintenance or the like. This “replacement time” is set at the time of maintenance, for example, and is updated by the control unit 110.

  The center device 11 receives the “maximum transmittable transmission output” and “corresponding modulation scheme” of the base station devices 12A to 12D from each base station device when the base station devices 12A to 12D are installed. Or, it is stored in the operation status table 2 by the input of the operator. Further, the center apparatus 11 determines “transmission output during operation”, “corresponding modulation scheme”, etc., and transmits a signal instructing the information to each base station apparatus and stores it in the operation status table 2.

  FIG. 3 is a diagram illustrating communication areas of the base station devices 12A to 12D. FIGS. 3A and 3B show communication areas 30A to 30D of the four base station apparatuses 12A to 12D (that is, ranges in which radio signals can be received with a predetermined intensity and S / N ratio). FIG. 3A illustrates a case where the communication area 30A of the base station device 12A overlaps with the communication areas 30B to 30D of the other three base station devices 12B to 12D. On the other hand, FIG. 3B shows a case where the communication area 30A of the base station device 12A does not overlap with any of the communication areas 30B to 30D of the other three base station devices 12B to 12D. The communication areas 30A to 30D are determined in accordance with, for example, the “maximum transmission output that can be transmitted” of the base station apparatuses 12A to 12D, or a predetermined ratio of the transmission output and the surrounding terrain. As will be described later, the communication areas 30A to 30D are enlarged or reduced by controlling the transmission outputs of the base station apparatuses 12A to 12D. The overlapping status of the communication areas 30A to 30D is input to the center device 11 and stored in the storage unit 112 when the base station devices 12A to 12D are newly installed.

  FIG. 4 is a flowchart showing an operation procedure of the mobile communication system 1. Here, the operation when the AC power supply of the base station apparatus 12A fails will be described. This procedure is executed, for example, at a predetermined cycle (cycle arbitrarily set such as several seconds to several hours).

  In the base station apparatus 12A, the power supply control unit 125 monitors the power supply state of the AC power supply and detects a change in the power supply state (power failure or power recovery). When the power supply control unit 125 detects a change in the power supply state of the AC power supply (Yes in S401), the control unit 120 performs an operation according to the result (power failure or power supply recovery).

  In the case of a power failure (“power failure” in S402), the base station apparatus 12A immediately switches to power supply from the standby power source 129 (S403). In addition, the base station apparatus 12A notifies the center apparatus 11 that a power failure has occurred and switched to power supply from the standby power supply 129 (S404), and notifies the center apparatus 11 of the power supply possible time of the standby power supply 129 (S405). For example, the control unit 120 obtains the chargeable time of the storage battery from the standby power supply 129 and obtains the power supply available time according to the charge amount.

  On the other hand, in the case of power supply recovery (“power supply recovery” in S402), the base station apparatus 12A switches to AC power supply (S406). Then, the base station apparatus 12A notifies the center apparatus 11 that AC power supply has been restored (S407).

  After step S405 or S407, the base station apparatus 12A waits for a transmission output change or modulation scheme change instruction from the center apparatus 11 (No in S408), and if there is an instruction from the center apparatus 11 (Yes in S408). It operates accordingly (S409).

  Here, when the base station device 12A is a control target and only the base station device 12A fails, the processing when the base station device 12A and the surrounding base station devices fail is divided into cases. explain.

[When only the base station device 12A fails]
FIG. 5 is a flowchart illustrating an example of an operation procedure when only the base station device 12A has a power failure. This procedure is executed when the base station apparatus 12A to 12D executes the procedure S404 or S407 of FIG. 4 to determine the base station apparatus that has failed in the center apparatus 11, for example, when only the base station apparatus 12A has failed. The

  The center apparatus 11 reads the overlapping status of the base station apparatus 12A to be controlled from the storage unit 112. For example, as shown in FIG. 3A, it is assumed that the communication area 30A of the base station device 12A overlaps with the communication areas 30B to 30D of other peripheral base station devices 12B to 12D. The center device 11 determines whether or not the communication areas of the base station device 12A and the surrounding base station devices overlap (S501). If they overlap (Yes in S501), the center device 11 Then, the transmission output is instructed to be reduced (S502), and the instructed content (transmission output reduction) is stored in the storage unit 112 (S503). In this case, even if the communication area 30A is reduced by reducing the transmission output of the base station device 12A, the mobile terminals 15 in the range covered by the communication areas 30B to 30D of the other base station devices 12B to 12D A base station can be secured. Therefore, the power consumption of the base station device 12A can be suppressed without impairing the communication quality of the entire system. By doing so, the continuous operation time of the base station apparatus 12A can be extended.

  On the other hand, as illustrated in FIG. 3B, it is assumed that the communication area 30A of the base station device 12A that is the control target does not overlap with the communication areas 30B to 30D of the other base station devices 12B to 12D in the vicinity. In this case (No in S501), the center apparatus 11 determines whether the outputs of the surrounding base station apparatuses 12B to 12D can be increased (S504). The center apparatus 11 makes a determination by comparing the maximum transmission output that can be transmitted from each of the base station apparatuses 12B to 12D stored in the operation status table 2 shown in FIG. 2 with the transmission output in operation. For example, as shown in the operation status table 2, the base station apparatus 12B has a transmission output in operation of 315 mW where the maximum transmission output that can be transmitted is 315 mW, and there is a margin for an increase in the transmission output. Judged to be possible. In addition, since the base station apparatuses 12C and 12D have a maximum transmission power that can be transmitted is 315 mW and the transmission power in operation is 200 mW and there is a margin for an increase in the transmission power, it is determined that the transmission power can be increased.

  When the center apparatus 11 determines that the transmission output of the surrounding base station apparatuses 12B to 12D can be increased (Yes in S504), the center apparatus 11 transmits a signal instructing the increase of the transmission output to the surrounding base station apparatuses 12B to 12D (S505). ), The designated content (increase in transmission output) is stored in the storage unit 112 (S506). And it returns to head step S501 and it is determined whether the communication area of base station apparatus 12A and the surrounding base station apparatuses 12B-12D overlaps. In this case, by increasing the transmission output of the peripheral base station apparatuses 12B to 12D, the communication areas of the base station apparatus 12A and the peripheral base station apparatus overlap, and the transmission output of the base station apparatus 12A is reduced. Even if the communication area of the base station apparatus 12A is reduced, the mobile terminals around the base station apparatus 12A can secure the connection destination. Therefore, the power consumption of the base station device 12A can be suppressed without impairing the communication quality of the entire system. By doing so, the continuous operation time of the base station apparatus 12A can be extended.

  When the center apparatus 11 determines that the transmission output of the surrounding base station apparatuses 12B to 12D cannot be increased (No in S504), the center apparatus 11 determines whether the traffic of the base station apparatus 12A is less than a predetermined threshold (S508). ). When the traffic of the base station device 12A is less than the threshold (Yes in S508), the center device 11 can communicate with the mobile terminal 15 even if the multi-value number of the communication method of the base station device 12A is lowered. A signal for instructing the base station apparatus 12A to reduce the multi-value number of the modulation scheme is transmitted (S509). When the multi-value number of the modulation method is lowered, the transmission / reception gain is increased, so that the transmission output can be lowered accordingly. Therefore, the center apparatus 11 transmits a signal for instructing a decrease in transmission output to the base station apparatus 12A (S510), and stores the contents instructed to the storage unit 112 (reduction in the number of multivalues and a decrease in transmission output) ( S511).

[When the base station apparatus 12A and the surrounding base station apparatus have a power failure]
FIG. 6 is a flowchart illustrating an example of an operation procedure when the base station device 12A and the surrounding base station devices have a power failure. In this procedure, the base station devices 12A to 12D execute the procedure S404 or S407 in FIG. 4 to determine the base station device that has failed in the center device 11, and for example, the base station device 12A and another base station device have a power failure When it is executed.

The center device 11 refers to the operation status table 2 of the storage unit 112 and calculates the operable time from the amount of charge and the average power consumption of the base station device that has failed due to the following [Equation 1] (S601). [Equation 1] is a calculation formula when the AC power supply is 100V.
[Formula 1] Operation possible time (h) = remaining power storage (Ah) / (average power consumption (W) / 100 (V))
For example, the operable time of the base station apparatuses 12A to 12D is as follows.
Operating time of base station apparatus 12A: 50 (Ah) / [60 (W) / 100 (V)] = 83.3 (h)
Operating time of base station apparatus 12B: 80 (Ah) / [100 (W) / 100 (V)] = 80.0 (h)
Operating time of base station apparatus 12C: 100 (Ah) / [110 (W) / 100 (V)] = 90.9 (h)
Operating time of base station apparatus 12D: 50 (Ah) / [85 (W) / 100 (V)] = 58.8 (h)

Next, the center apparatus 11 makes a list in order from the base station apparatus with a short operable time (S602). For example, the base station apparatuses 12A to 12D are listed as follows in ascending order of operable time.
Operating time of base station device 12D: 58.8 (h)
Operating time of base station apparatus 12B: 80.0 (h)
Operating time of base station apparatus 12A: 83.3 (h)
Operating time of base station apparatus 12C: 90.9 (h)

  Next, the center apparatus 11 selects the base station apparatus with the shortest operable time (S603), and executes the procedure of FIG. 5 (S604). For example, the procedure of FIG. 5 is executed for the base station device 12D. For example, if the base station device 12D is in the overlapping state of FIG. 3A, the base station device 12D has a communication area overlapping with the base station device 12A, and therefore the center device 11 sends a transmission output to the base station device 12D. Reduce. On the other hand, in the overlapping state of FIG. 3B, the base station device 12D does not overlap the communication area with other base station devices. Therefore, the center apparatus 11 increases the transmission output of the base station apparatuses 12A to 12C if possible, and decreases the transmission output to the base station apparatus 12D.

  Next, the center apparatus 11 selects the base station apparatus with the second shortest operable time (S605), and executes the procedure of FIG. 5 (S606). For example, the procedure of FIG. 5 is executed for the base station apparatus 12B.

  Next, the center apparatus 11 selects the base station apparatus with the third operable time (S607), and executes the procedure of FIG. 5 (S608). For example, the procedure of FIG. 5 is executed for the base station apparatus 12A.

  Then, the center apparatus 11 selects the base station apparatus having the longest operable time (S609), and executes the procedure of FIG. 5 (S610). For example, the procedure of FIG. 5 is executed for the base station apparatus 12C. Note that steps S603 and S604, S605 and S606, S607 and S608, and steps S609 and S610 are repeated a number of times according to the number of base station apparatuses.

  According to the above procedure, it is possible to smoothly reduce the power consumption of a plurality of base station devices that are out of power. Further, by reducing the transmission output from the base station apparatus that has the shortest operable time and therefore the highest necessity for extending the continuous operation time, it is possible to efficiently extend the operation time of the entire system.

  FIG. 7A is a flowchart showing another example of the procedure when the base station apparatus 12A and its peripheral base station apparatus have a power failure. The procedure in FIG. 7 is executed, for example, when the determination result is “No” in step S508 in FIG. That is, this is a process in the case where the base station apparatus 12 </ b> A has a power outage, but the amount of traffic is large and communication power with the mobile terminal 15 is hindered when the transmission output is reduced by changing the modulation method.

  The center apparatus 11 calculates the operable time (Ta) of the base station in the power outage in the same manner as in step S601 in FIG. 6 (S701). And the center apparatus 11 reads the replacement time (Tb) until completion of replacement | exchange of the storage battery of each base station apparatus from the operation condition table 2 (S702). The center apparatus 11 determines whether Ta / Tb ≧ 1 is true or false (S703). If Ta / Tb ≧ 1 (Yes in S703), the operable time of the storage battery is longer than the time required for replacement of the storage battery. Therefore, the base station apparatus 12A can continue to operate without any particular processing. On the other hand, in the case of Ta / Tb <1 (No in S703), if the base station device 12A is operated as it is, the charge amount disappears before the storage battery is replaced by the next maintenance, and the operation of the base station device is stopped. According to the table of FIG. 7B, a transmission output corresponding to the range of Ta / Tb values is obtained (S704), an instruction is sent to the base station apparatus 12A to perform transmission with the obtained output (S705), and the center apparatus The instructed contents are stored in the storage unit 11 (S706). The larger the value of Ta / Tb, the longer the operable time with respect to the time until replacement is possible, so that even if transmission is performed with a larger transmission output, continuous operation is possible.

  According to the procedure as described above, the continuous operation can be performed without impairing the communication quality of the entire system. As described above, the amount of decrease when the center apparatus 11 decreases the transmission output of the base station apparatus may be arbitrary. For example, the case where transmission is stopped is also included in the present embodiment. Further, the number of base station apparatuses is not limited to the above, and may be any plural number.

  Although the present invention has been described above based on the drawings and examples, it should be noted that those skilled in the art can easily make various changes and modifications based on the present disclosure. Therefore, it should be noted that these variations and modifications are included in the scope of the present invention. For example, the functions included in each means, each step, etc. can be rearranged so that there is no logical contradiction, and a plurality of means, steps, etc. can be combined or divided into one. . Further, the numbers of the circuit station devices and relay station devices described above are examples, and combinations other than the above-described combinations are possible.

DESCRIPTION OF SYMBOLS 1 Mobile communication system 11 Center apparatus 12 Base station apparatus 129 Standby power supply

Claims (10)

A plurality of base station devices that receive power from the storage battery during a power failure and perform wireless communication with mobile terminals in the communication area;
An instruction to reduce the transmission output to the first base station device receiving power supply from the storage battery at the time of a power failure on condition that the communication area of the first base station device overlaps with the communication area of the second base station device A center device for performing control processing,
A mobile communication system. In claim 1,
When the communication area of the first and second base station apparatuses does not overlap, the center apparatus sends an instruction to increase the transmission output to the second base station apparatus, and then performs the control process Communications system. In claim 1,
The center apparatus performs the control process on the condition that communication traffic of the first base station apparatus is less than a predetermined value even when communication areas of the first and second base station apparatuses do not overlap. A mobile communication system. In any one of Claims 1 thru | or 3,
The mobile communication system in which the transmission output for the storage amount of the storage battery in the first base station apparatus is larger than the transmission output for the storage amount of the storage battery in the second base station apparatus. A wireless communication unit that communicates with a plurality of base station devices that receive power from a storage battery and perform wireless communication with a mobile terminal in a communication area at the time of a power failure;
An instruction to reduce the transmission output to the first base station device receiving power supply from the storage battery at the time of a power failure on condition that the communication area of the first base station device overlaps with the communication area of the second base station device A control unit for performing control processing to send,
A center device. In claim 5,
The control unit performs the control process after sending an instruction to increase the transmission output to the second base station device when the communication areas of the first and second base station devices do not overlap . In claim 5,
The control unit performs the control process on the condition that the communication traffic of the first base station apparatus is less than a predetermined value even if the communication areas of the first and second base station apparatuses do not overlap. Center device that performs. In any of claims 5 to 7,
The center device having a transmission output for the storage amount of the storage battery in the first base station device larger than the transmission output for the storage amount of the storage battery in the second base station device. A control method for a plurality of base station devices that receive power supply from a storage battery during a power failure and perform wireless communication with a mobile terminal in a communication area,
Control in which the first base station device that receives power supply from the storage battery at the time of a power failure reduces the transmission output on condition that the communication area of the first base station device overlaps with the communication area of the second base station device Method. In the processor of the center device that receives power supply from the storage battery at the time of a power failure and communicates with a plurality of base station devices that perform wireless communication with mobile terminals in the communication area,
An instruction to reduce the transmission output to the first base station device receiving power supply from the storage battery at the time of a power failure on condition that the communication area of the first base station device overlaps with the communication area of the second base station device Execute the control process to send
program.

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