JP2021078070A - Radio communication device, radio collection device, radio communication system, control method, and control program - Google Patents

Abstract

To provide a radio communication device capable of efficiently reporting the power status, a radio collection device, a radio communication system, a control method, and a control program.SOLUTION: A radio communication device 100 includes: a calculation unit 101 that calculates power outage operation capable time in which communication operation is capable of being performed even when power is stopped; a notification unit 102 that notifies the calculated power outage operation capable time to a radio collection unit 110; and a reporting unit 103 that is configured to, when a power outage is detected, report the power outage to the radio collection unit 110 at a power outage report timing specified by the radio collection unit 110 depending on the power outage operation capable time.SELECTED DRAWING: Figure 2

Description

The present invention relates to wireless communication devices, wireless collection devices, wireless communication systems, control methods and control programs.

In recent years, wireless communication systems using wireless communication such as wireless LAN (Local Area Network), Bluetooth (registered trademark), and mobile phone communication have become widespread. In such a wireless communication system, various data and various data can be generated as needed between a wireless collection device that is a master station such as a base station or an access point and a plurality of wireless communication devices that are slave stations such as a wireless terminal device. Messages are sent and received.

As related techniques, for example, Patent Documents 1 to 3 are known. According to Patent Document 1, maintenance data is transmitted from the slave unit when the remaining battery level of the slave unit falls below the threshold value in order to avoid a situation in which the slave unit cannot be used due to the battery running out in the emergency notification system. It is stated that it should be done. According to Patent Document 2, in the alarm transfer method, the transmission retry time of the subscriber station device is shortened in the case of a highly urgent failure according to the priority of the priority level of the failure caused by the subscriber station device, and the urgency is determined. It is stated that an alarm is transmitted by increasing the transmission retry time in the case of a low failure. Patent Document 3 describes transmission using a random delay period in order to avoid collision of radio nodes.

As other related techniques, Patent Document 4 describes a capacitor quality determination device, Patent Document 5 describes a capacitor deterioration detection circuit, and Patent Document 5 describes a battery discharge time prediction. The device is described.

Japanese Unexamined Patent Publication No. 2002-197574 Japanese Unexamined Patent Publication No. 2000-341207 JP-A-2009-105892 Japanese Patent No. 4362962 Japanese Unexamined Patent Publication No. 2010-23425 Japanese Unexamined Patent Publication No. 2001-07763

With the above-mentioned related technologies, it is possible to report the power status from the slave station to the master station according to the remaining battery level, but when the power supplied to the slave station is stopped, the slave station will report the power status to the master station. I can't call the station. On the other hand, when the power is stopped, it is conceivable to use the backup power supply to notify the master station of the power supply status from the slave station. However, in the related technology, since the use of a backup power supply is not considered, there is a problem that it may not be possible to efficiently report the power supply status depending on the timing.

In view of such problems, it is an object of the present disclosure to provide a wireless communication device, a wireless collection device, a wireless communication system, a control method, and a control program capable of efficiently reporting the state of a power source.

The wireless communication device according to the present disclosure includes a calculation unit that calculates a power failure operation possible time during which communication operation is possible when the power is stopped, a notification unit that notifies the wireless collection device of the calculated power failure operation time, and the power stop. When is detected, the wireless collection device is provided with a notification unit for notifying the wireless collection device of the power stop at the power failure notification timing instructed by the wireless collection device according to the power failure operation possible time.

The wireless collecting device according to the present disclosure includes a determination unit that determines a power failure notification timing when the power of the wireless communication device is stopped, and a determined power failure notification timing based on the power failure operation possible time notified from the wireless communication device. Is provided with an instruction unit for instructing the wireless communication device.

The wireless communication system according to the present disclosure is composed of a plurality of the wireless communication devices and the wireless collection device.

One control method according to the present disclosure is the control method of the wireless communication device. Further, another control method according to the present disclosure is a control method of the wireless collection device.

Yet another control method according to the present disclosure is the control method of the wireless communication system.

One control program according to the present disclosure is a control program characterized in that a computer functions as the wireless communication device. Further, another control program according to the present disclosure is a control program characterized in that the computer functions as the wireless collecting device.

Yet another control program according to the present disclosure is the control program of the wireless communication system.

According to the present disclosure, it is possible to provide a wireless communication device, a wireless collection device, a wireless communication system, a control method, and a control program capable of efficiently reporting the state of a power source.

It is a block diagram which shows the outline of the wireless communication system which concerns on embodiment. It is a block diagram which shows the outline of the wireless communication apparatus which concerns on embodiment. It is a block diagram which shows the outline of the wireless collection apparatus which concerns on embodiment. It is a block diagram which shows the structural example of the wireless communication system which concerns on Embodiment 1. FIG. It is a sequence diagram which shows the operation example of the wireless communication system which concerns on Embodiment 1. FIG. It is a block diagram which shows the network configuration example of the wireless communication system which concerns on Embodiment 1. FIG. It is a timing diagram which shows the communication timing in the wireless communication method of the comparative example. It is a timing diagram which shows the communication timing in the wireless communication method which concerns on Embodiment 1. FIG. It is a block diagram which shows the other network configuration example of the wireless communication system which concerns on Embodiment 1. FIG. It is a timing diagram which shows the communication timing in the wireless communication method of the comparative example. It is a timing diagram which shows the communication timing in the wireless communication method which concerns on Embodiment 1. FIG. It is a block diagram which shows the structural example of the wireless communication system which concerns on Embodiment 2. FIG. It is a block diagram which shows the network configuration example of the wireless communication system of the comparative example. It is a timing diagram which shows the communication timing in the wireless communication method of the comparative example. It is a block diagram which shows the network configuration example of the wireless communication system which concerns on Embodiment 2. FIG. It is a timing diagram which shows the communication timing in the wireless communication method which concerns on Embodiment 2. It is a block diagram which shows the structural example of the wireless communication system which concerns on Embodiment 3. It is a block diagram which shows the network configuration example of the wireless communication system of the comparative example. It is a block diagram which shows the network configuration example of the wireless communication system which concerns on Embodiment 3. It is a timing diagram which shows the communication timing in the wireless communication method of the comparative example. It is a timing diagram which shows the communication timing in the wireless communication method which concerns on Embodiment 3.

Hereinafter, embodiments will be described with reference to the drawings. In each drawing, the same elements are designated by the same reference numerals, and duplicate explanations are omitted as necessary.

(Examination leading to the embodiment)
The inventor examines the related technology before the application of the embodiment, and the problem is that the related technology cannot efficiently collect information in a short time when a large number of wireless communication devices detect a power outage at the same time. I found.

That is, it is known that there are "hidden terminal problem" and "exposed terminal problem" as problems when a plurality of wireless devices communicate at the same time. The "hidden terminal problem" is a problem in which a collision of transmitted data occurs in a receiving device when two or more transmitting devices transmit data at the same time. The "exposed terminal problem" is a problem in which a certain transmitting device intercepts data communication of another adjacent transmitting device to suppress unnecessary transmission. Although methods for avoiding these problems have been widely studied, related technologies have not considered a method for efficiently collecting information in a short time when the power is stopped.

For example, as a means for easily constructing a monitoring network, a wireless communication device (called a “slave station”) is installed for each power transmission line that branches into a large number of lines, and a wireless collection device (“master station”) is installed for each fixed area. However, it is conceivable to collect power stop information of slave stations within the communication range at once and monitor the transmission line route. In this case, since there is no relationship between the transmission line route and the wireless area of the master station, it is possible to identify the fault occurrence route by clarifying all the transmission destinations (= slave stations) that have detected the power outage. ..

Here, in the related technology, if a failure occurs before the transmission line branches, multiple slave stations will detect and notify the power outage at the same time, and the "exposed terminal problem" and "exposed terminal problem" will occur. It is affected, and the degree of this effect increases as the range of failure increases. In addition, the slave station needs to secure the power supply by itself in order to notify the power stop after the power supply is stopped. As a means for easily securing a power source, a backup circuit using an aluminum electrolytic capacitor, a supercapacitor, a battery, a battery, or the like can be considered. In this backup circuit, it is necessary to lengthen the communicable time according to the time required to deal with the "hidden terminal problem" and the "exposed terminal problem". Further, since the components of this circuit have a limited life and the degree of deterioration is accelerated depending on the usage environment, the backup communication possible time differs for each slave station even if the same type of components are used. The backup communication possible time is the time during which the power stop notification can be given from the detection of the power supply stop to the stop of the function. In order to collect power supply information from a large number of slave stations in this finite backup communication available time, it is necessary to realize efficient information collection in a short time.

(Outline of Embodiment)
FIG. 1 shows an outline of a wireless communication system according to an embodiment, FIG. 2 shows an outline of a wireless communication device according to an embodiment, and FIG. 3 shows an outline of a wireless collection device according to an embodiment. ing.

As shown in FIG. 1, the wireless communication system 120 according to the embodiment includes a plurality of wireless communication devices 100 (for example, 100A and 100B) and a wireless collection device 110. The wireless communication device 100 is a slave station, and the wireless collection device 110 is a master station that collects wireless communication of a plurality of wireless communication devices 100.

As shown in FIG. 2, the wireless communication device 100 includes a calculation unit 101, a notification unit 102, and a notification unit 103. Further, as shown in FIG. 3, the wireless collection device 110 includes a determination unit 111 and an instruction unit 112.

In the wireless communication device 100, the calculation unit 101 calculates the power failure operation possible time during which the communication operation is possible when the power is stopped, and the notification unit 102 notifies the wireless collection device 110 of the calculated power failure operation possible time. The power failure operationable time is the time during which the notification can be made by the backup power supply when the power supply is stopped. In the wireless collection device 110, the determination unit 111 determines the power failure notification timing when the power of the wireless communication device 100 is stopped, and the instruction unit 112 determines the determined power failure notification timing based on the notified power failure operation possible time. Instruct the wireless communication device 100. The power failure notification timing is the timing from when the power is stopped until the power failure operation time elapses, and is determined based on, for example, the comparison result of the power failure operation time of the plurality of wireless communication devices 100. Further, in the wireless communication device 100, when the power stop is detected, the reporting unit 103 notifies the wireless collecting device 110 of the power stop at the instructed power failure notification timing.

As described above, in the related technology, when the power is stopped, multiple wireless communication devices make a report at the same time, so that congestion / collision occurs and the wireless collection device cannot receive the report signal. It will occur. When communication fails due to the occurrence of a collision (for example, ACK is not received in a predetermined period), the wireless communication device waits for a certain period of time and then tries to retransmit. At this time, since the wireless communication device has lost the operating power supply due to the power failure, it tries to retransmit the report by the backup power supply. However, since there is a possibility that the backup power supply is completely consumed by the notification after the power failure occurs, a situation in which re-transmission cannot be performed may occur. Therefore, a method is desired in which the master station efficiently receives reports from all wireless communication devices while communication is possible with a backup power source without causing collision of report signals.

Therefore, in the embodiment, the wireless collection device determines the power failure notification timing (power stop notification timing) of the wireless communication device based on the power failure operation possible time (backup communication possible time) calculated by the wireless communication device, and wireless communication is performed. Instruct the device when to report a power failure. As a result, the occurrence of collision of the notification signal can be suppressed, and the occurrence of a power failure can be reliably notified (notified) from all the wireless communication devices to the wireless collection device in a shorter time and more efficiently.

(Embodiment 1)
Hereinafter, the first embodiment will be described with reference to the drawings. FIG. 4 shows the configuration of the wireless communication system according to the present embodiment. As shown in FIG. 4, the wireless communication system 5 according to the embodiment includes a plurality of slave stations 1 (for example, 1A and 1B) and a master station 2. The plurality of slave stations 1 have the same configuration, and the same power supply is supplied to the plurality of slave stations 1. The wireless communication system 5 is a system that collects power stop information of a plurality of slave stations 1 and outputs them to a monitoring system.

The slave station 1 measures and calculates the backup communication possible time during which the power stop notification is possible from the detection of the power supply stop of the own station to the stop of its function, and backs up the own station to the master station 2. It is a device that has a function of notifying the communication available time and a function of notifying the power stop at the timing instructed by the master station when the power stop is detected. The master station 2 is a device having a function of comparing the backup communication available times notified from a plurality of slave stations and giving an instruction to preferentially transmit a slave station having a short backup communication available time in advance.

The functions of each block of the slave station 1 and the master station 2 will be described. As shown in FIG. 4, the slave station 1 includes a backup power supply unit 11, a backup communication available time determination & notification unit 12, a power supply stop detection unit 13, a power supply stop notification timing control unit 14, a wireless transmission unit 15, and a wireless reception unit 16. Equipped with. A power source (main power source) is supplied to each block of the slave station 1 from the outside. The wireless transmission unit 15 and the wireless reception unit 16 have basic wireless communication functions. The wireless transmission unit 15 and the wireless reception unit 16 perform wireless transmission and wireless reception with the master station 2 via the antenna 31 according to a communication standard such as a wireless LAN.

The backup power supply unit 11 is a backup power supply for operating the own station even after the power supply is stopped. The backup power supply unit 11 is, for example, an aluminum electrolytic capacitor, a supercapacitor, a battery, a battery, or the like. When the power is stopped, the backup power supply unit 11 supplies power only to the block required for the power stop notification. By limiting the block to which the backup power supply unit 11 supplies power to only the block required for the power stop notification, the power consumption of the slave station 1 can be suppressed.

The backup communication available time determination & notification unit 12 is a calculation unit that calculates the backup communication possible time (power failure operation possible time), and is also a notification unit that notifies the calculated backup communication possible time. Specifically, the backup communication possible time determination & notification unit 12 has a function of measuring the charge time or discharge time of the backup power supply unit 11. For example, the charging time or the discharging time may be measured by the method described in Patent Document 4. It is generally known that the capacity of the backup power supply unit 11 deteriorates and the charging time or discharging time becomes longer. The backup communication possible time determination & notification unit 12 may store the conversion data capable of estimating the capacity of the backup power supply unit 11 deteriorated from the charging time or the discharging time in the storage unit of the slave station 1. Then, the backup communication possible time determination & notification unit 12 calculates the backup communication possible time that the own station can communicate with only the backup power supply from the capacity of the backup power supply unit 11 estimated from the measurement result, and causes the wireless transmission unit 15 to communicate. It is used to notify the power stop notification timing determination unit 24 of the master station 2.

Here, as the measurement data used for estimating the capacity of the backup power supply unit 11, a method such as input current peak comparison as described in Patent Document 5 may be used. In addition, it is known that changes in power supply capacity are affected by the surrounding environment (temperature, humidity, vibration, etc.), and the power supply capacity is based on the function of measuring temperature, humidity, vibration, etc. and the measurement results. It may have a function of correcting the calculation. Further, the discharge time is predicted from the difference between the discharge rate obtained from the initial discharge voltage and the discharge current as described in Patent Document 6 and the same value after the power supply unit is deteriorated, and the backup communication possible time is calculated from the power consumption of the device. You can also use the method. Further, it may be a function of temporarily shutting off the power input by itself and actually measuring the time during which the slave station 1 can operate.

The power stop detection unit 13 detects the stop (power stop) of the power supplied from the external power source, and notifies the power stop notification timing control unit 14 of the detected power stop (detection signal).

The power stop notification timing control unit 14 is a power stop notification unit (reporting unit) that notifies (reports) the power stop to the master station 2 at the power stop notification timing instructed in advance from the master station 2 when the power is stopped. is there. Specifically, the power stop notification timing control unit 14 notifies the power stop notification extraction unit 23 of the master station 2 of the power stop by using the detection signal of the power stop detection unit 13 as a trigger. At this time, it is provided with a timer function that adjusts the notification timing so that it becomes the power stop notification timing instructed in advance by the master station 2.

As shown in FIG. 4, the master station 2 includes a wireless reception unit 21, a wireless transmission unit 22, a power stop notification extraction unit 23, and a power stop notification timing determination unit 24. The wireless receiving unit 21 and the wireless transmitting unit 22 have basic wireless communication functions as in the slave station 1. The wireless receiving unit 21 and the wireless transmitting unit 22 perform wireless reception and wireless transmission between the slave stations 1 via the antenna 32 in accordance with a wireless communication standard such as a wireless LAN.

The power stop notification timing determination unit 24 determines the order of notification of each slave station 1 and the notification timing of power stop based on the value of the backup communication possible time of each slave station 1 received by the wireless reception unit 21 of its own station. It is a judgment unit (decision unit) for determining (determining). The power stop notification timing determination unit 24 determines the notification timing so that the transmission operation of the power stop notification in each slave station 1 ends within the respective backup communication possible time. For example, the backup communication available time of each slave station 1 may be compared, and the notification timing may be determined so that the backup communication available time is notified in ascending order. Further, the power stop notification timing determination unit 24 is an instruction unit that instructs the power stop notification timing control unit 14 of the slave station 1 by using the wireless transmission unit 22 to indicate the determined power stop notification timing.

The power stop notification extraction unit 23 detects (receives) the power stop notification from the slave station 1 and notifies the monitoring system of the power stop of the slave station 1.

Next, an operation example of the master station 2 and the slave stations 1A and 1B of FIG. 4 will be described with reference to the sequence diagram of FIG. First, each of the backup communication available time determination & notification unit 12 of the slave stations 1A and 1B determines the backup communication available time based on the capacity of the backup power supply unit 11 (S101, S103), and determines the determined backup communication available time. Notify the master station 2 (S102, S104). The backup communication available time may be notified at the timing when the slave station 1 (own station) is activated and wireless communication with the master station 2 is established, or the request from the master station 2 is responded to. You may notify with. Here, the notification timing may be a function of autonomously notifying at a periodic cycle set by the timer of the slave station itself.

Subsequently, the power stop notification timing determination unit 24 of the master station 2 determines the power stop notification timing of the slave stations 1A and 1B based on the backup communication available time received from the slave stations 1A and 1B (S105), and determines. The power stop notification timing is instructed to the slave stations 1A and 1B (S106, S107). Here, the determination and instruction of the notification timing by the power stop notification timing determination unit 24 is determined and instructed so that the slave station having the short backup communication available time gives priority to the notification. The notification timing instructed to the slave stations 1A and 1B is controlled so as to be the shortest timing at which the notification timings can be continuously realized without overlapping the notification timings of the slave stations 1A and 1B. For example, the master station 2 instructs the slave station 1A to notify the notification timing T1, and instructs the slave station 1A to notify the notification timing T2. T1 is the timing within the backup communication available time of the slave station 1A, and T2 is the timing within the backup communication available time of the slave station 1B.

Subsequently, when the power supplied to the slave stations 1A and 1B is stopped (S108), the power stop detection unit 13 of the slave stations 1A and 1B detects the power stop (S109, S110). Then, each of the power stop notification timing control units 14 of the slave stations 1A and 1B notifies the master station 2 of the power stop at the power stop notification timing instructed by the master station 2 (S111, S113). For example, the slave station 1A notifies the power stop at the timing when T1 elapses from T0 when the power stop is detected, and the slave station 1B notifies the power stop when T2 elapses from T0 when the power stop is detected.

Subsequently, the power stop notification extraction unit 23 of the master station 2 extracts (receives) the power stop notification from the slave stations 1A and 1B (S112, S114), and notifies the monitoring system of the power stop of the slave stations 1A and 1B. .. The master station 2 receives the power stop notification from each of the slave stations 1A and 1B at the notification timings (for example, T1 and T2) controlled so as to be continuous without duplication.

Next, a communication method according to the present embodiment using the master station 2 and the slave station 1 of FIG. 4 will be described with reference to the network configuration example of FIG. The network configuration example of FIG. 6 includes a master station 2 and slave stations 1A and 1B, the master station 2 and slave station 1A perform wireless communication in the communication area 202A, and the master station 2 and slave station 1B communicate in the communication area 202B. Perform wireless communication with. Further, the slave stations 1A and 1B are supplied with the same power supply from the power supply 3.

The slave station 1A monitors the power supply of the power transmission line 201A supplied from the power source 3, and when the power stop is detected, notifies the master station 2 of the power stop information. Similarly, the slave station 1B monitors the power supply of the power transmission line 201B supplied with power from the power supply 3, and when a power stop is detected, notifies the master station 2 of the power stop information. Here, the slave station 1A is located outside the communication zone 202B of the slave station 1B, and the slave station 1B is located outside the communication zone 202A of the slave station 1A. That is, the slave station 1A and the slave station 1B are located outside the reach of each other's radio signals.

First, FIG. 7 shows, as a comparative example, a communication timing diagram when the communication method according to the present embodiment is not used. FIG. 7 shows an example in which a data collision occurs when the slave station 1A and the slave station 1B that have detected the power outage communicate at the same time in the network configuration of FIG.

As shown in FIG. 7, when the power supply 3 fails and stops functioning, the slave station 1A and the slave station 1B detect the power stop at the same timing and immediately transmit the data notifying the master station 2 of the power stop at t0. To do. However, if the master station 2 receives data from the slave station 1A and the slave station 1B at the same time, a data collision occurs, so that the master station 2 cannot correctly receive the data and cannot return the Ac to the slave stations 1A and 1B. Then, since the slave station 1A and the slave station 1B do not receive the Ac from the master station 2 within a predetermined period, the failure of data transmission is detected and the retransmission process is performed. Here, in order to avoid the occurrence of data collision, for example, there is a method of providing a random delay as described in Patent Document 3 and shifting the transmission timing for each device. In this example, the slave station 1A retransmits the data to t1 after the random delay, and then the slave station 1B retransmits the data to t2 after the random delay.

On the other hand, FIG. 8 is a timing diagram of communication by the communication method according to the present embodiment with respect to the comparative example of FIG. 7. Here, the slave station 1A and the slave station 1B notify the master station 2 of the backup communication possible time of their own station in advance as described in the operation explanation of FIG. 5, and transmit the power stop notification data (t3, t4). ) Has been instructed. In the example of FIG. 8, the slave station 1A transmits data to t3 immediately after the power stop is detected according to the instruction of the master station 2. Further, the slave station 1B transmits data to t4 after waiting for transmission for a time until the communication between the slave station 1A and the master station 2 is completed according to the instruction of the master station 2. By performing communication by the communication method according to the present embodiment, data collision can be avoided, and all communication can be performed in a shorter time than in the comparative example of FIG.

Next, the communication method according to the present embodiment will be described with reference to another network configuration example of FIG. The network configuration example of FIG. 9 includes master stations 2A and 2B and slave stations 1A and 1B. The master station 2A and slave station 1A perform wireless communication in the communication area 202A, and the master station 2B and slave station 1B communicate with each other. Wireless communication is performed in the service area 202B. Further, the slave stations 1A and 1B are supplied with the same power supply from the power supply 3.

The slave station 1A monitors the power supply of the power transmission line 201A supplied from the power source 3, and when the power stop is detected, the slave station 1A notifies the master station 2A of the power stop information. Similarly, the slave station 1B monitors the power supply of the power transmission line 201B supplied from the power source 3, and when a power stop is detected, notifies the master station 2B of the power stop information. Here, the slave station 1A is located in the communication zone 202B of the slave station 1B, and the slave station 1B is located in the communication zone 202A of the slave station 1A. That is, the slave station 1A and the slave station 1B are located within the reach of each other's radio signals, and receive each other's transmission signals.

First, FIG. 10 shows, as a comparative example, a communication timing diagram when the communication method according to the present embodiment is not used. FIG. 10 shows an example in which the data transmission timing of the slave station 1B is delayed due to the carrier sense among the slave station 1A and the slave station 1B that have detected the power outage in the network configuration of FIG.

As shown in FIG. 10, in this example, when the slave station 1A and the slave station 1B detect the power stop, the slave station 1A first transmits data notifying the master station 2 of the power stop at t5 immediately after the detection. At this time, when the carrier sense for the timing of communication by the slave station 1B is performed, the data transmitted from the slave station 1A to the master station 2A is detected, so that the data is sent to the master station 2B at t6 after the random delay. To send.

On the other hand, FIG. 11 is a timing diagram of communication by the communication method according to the present embodiment with respect to the comparative example of FIG. Similar to FIG. 8, the slave station 1A and the slave station 1B notify the master station 2A and the master station 2B of the backup communication possible time of their own stations in advance, respectively, and receive an instruction of the transmission timing (t7) of the power stop notification data. ing. Here, since the master station 2A is outside the communication range of the slave station 1B and the master station 2B is outside the communication range of the slave station 1A, the master station 2A and the master station 2B are both the slave station 1A and the slave station 1B. It is instructed to transmit data at t7 immediately after the power stop is detected, and the slave station 1A and the slave station 1B transmit data at the same timing of t7 according to the instruction. By communicating by the communication method according to the present embodiment, the slave station 1B can avoid the delay due to the carrier sense and perform all the communication in a shorter time than the comparative example of FIG.

In the examples of FIGS. 6 and 9, the network is composed of two slave stations, but even if the number of slave stations is N and the number of devices is increased, the same communication method can be used in a shorter time. All communications can be performed. Further, the master station and the slave station may be provided with a function of periodically checking the backup communication available time and reviewing the transmission order and timing of the power stop notification. Further, the master station and the slave station may be provided with a function of detecting and correcting a time lag when the actual communication time is shortened (or extended) with respect to a predetermined transmission time. .. Further, the master station may be provided with a function of detecting a slave station that is not in time for transmission as a result of scheduling the transmission timing of the power stop notification data of the slave station and notifying the monitoring system of an alarm. Furthermore, instead of using the time from power stop detection to transmission as the method of instructing the power stop notification timing, the ID of another slave station to be notified before the own station is notified, and the master station for the corresponding slave station is notified. It may be a function of intercepting the Ac signal of the above and using it as a transmission start trigger of the own station.

As described above, in the present embodiment, when the wireless communication devices are simultaneously powered down, it is possible to collect power stop notifications from more wireless communication devices in a short time. That is, the master station specifies the transmission timing of the power stop notification to the slave station in advance, so that when the power stop occurs at the same time, the master station retransmits due to the "exposed terminal problem" or the "exposed terminal". Avoid waiting for transmission. In addition, by comparing the backup communication available times of the slave stations and preferentially communicating the slave stations with the shorter corresponding time, it is possible to collect power stop notifications from more slave stations in a short time. Here, the slave station calculates the time (backup communication possible time) during which the power stop notification is possible from the detection of the power supply stop to the stop of its function, and the slave station can perform its own backup communication with the master station. It is equipped with a function to notify the time and a function to notify the power stop at a specified timing according to the instruction of the master station. Then, the master station has a function of determining an efficient communication order from the backup communication available time notified from the plurality of slave stations and a function of designating the transmission timing for the slave station. As a result, the transmission timing of the slave station is controlled from the master station, and the power stop communication is efficiently performed, so that the information of the power stop notification can be surely obtained from more slave stations.

(Embodiment 2)
Hereinafter, the second embodiment will be described with reference to the drawings. In this embodiment, an example in which a relay station function is provided in addition to the configuration of the first embodiment will be described.

FIG. 12 shows the configuration of the wireless communication system according to the present embodiment. As shown in FIG. 12, the wireless communication system 6 according to the present embodiment includes a relay station 4 between the master station 2 and the slave station 1 (1B in this example). The relay station 4 has a function of relaying between the slave station 1B and the master station 2 in addition to the function of the slave station 1A according to the first embodiment of FIG. In the present embodiment, the master station 2 may determine the notification timing of each slave station 1 in consideration of the number of slave stations to be relayed.

The relay station 4 includes a backup power supply unit 11 of the slave station 1A of FIG. 14, a backup communication possible time determination & notification unit 12, a power supply stop detection unit 13, a power supply stop notification timing control unit 14, a wireless transmission unit 15, and a wireless reception unit 16. It has the same function as that of the above, and also has a power supply stop detection multiplex unit 17.

The power stop detection multiplex unit 17 receives the power stop detection signal of the slave station 1B according to the instruction from the master station 2, and the power stop detection unit 13 of the own station (relay station 4) receives the power stop detection signal of the slave station 1B. This is a function of generating a signal in which the detection results of the above are multiplexed and notifying the power stop notification timing control unit 14. The power stop notification timing control unit 14 notifies the power stop notification extraction unit 23 of the master station 2 of the detection signal in which the power stop detection signal of the slave station 1B and the power stop detection signal of the own station are multiplexed.

Next, a communication method according to the present embodiment using the function of the relay station 4 of FIG. 12 will be described. First, FIG. 13 shows an example of a network configuration in which the function of the relay station 4 of FIG. 12 is not used as a comparative example. The network configuration example of FIG. 13 includes a master station 2 and slave stations 1A to 1C, and communicates between the master station 2 and the slave station 1A, the master station 2 and the slave station 1B, and the master station 2 and the slave station 1C, respectively. I do. Further, the slave stations 1A to 1C are supplied with the same power supply from the power supply 3.

The slave station 1A monitors the power supply of the power transmission line 201A supplied from the power source 3, and when the power stop is detected, notifies the master station 2 of the power stop information. Similarly, the slave station 1B monitors the power supply of the power transmission line 201B supplied with power from the power supply 3, and when a power stop is detected, notifies the master station 2 of the power stop information. The slave station 1C monitors the power supply of the power transmission line 201C to which power is supplied from the power supply 3, and when a power stop is detected, notifies the master station 2 of the power stop information.

FIG. 14 is a communication timing diagram of a comparative example similar to that of the first embodiment in the network configuration of FIG. Similar to the first embodiment, each of the slave station 1A, the slave station 1B, and the slave station 1C notifies the master station 2 of the backup communication available time of its own station in advance, and the transmission timing of the power stop notification data (t8, Received instructions from t9 and t10). In this example, the master station 2 instructs the transmission timing so that the slave station 1A, the slave station 1B, and the slave station 1C are in the order of the shortest backup communication possible time, and the slave station 1A and the slave station 1B are instructed. , The slave station 1C transmits data to t8, t9, and t10, respectively, according to the instruction. Therefore, as in the first embodiment, the slave stations 1A to 1C can notify the power stop in a short time while avoiding data collision.

On the other hand, FIG. 15 shows an example of a network configuration in which the relay station 4 according to the present embodiment is applied to the network configuration of FIG. As shown in FIG. 15, in this example, the slave station 1C has the function of the relay station 4 of FIG. 12 and operates as a relay station of the slave station 1B.

FIG. 16 is a communication timing diagram according to the present embodiment in the network configuration of FIG. The master station 2 instructs the slave station 1B in advance to communicate with the slave station 1C at t11 immediately after the power stop is detected, and instructs the slave station 1C to communicate with the slave station 1B with the communication result of the slave station 1B. Instructs the timing (t12) for multiplex communication of station monitoring results. At this time, as the communication signal between the slave station 1A and the master station 2 and the communication signal between the slave station 1B and the slave station 1C, a frequency band that is not affected by each other or a carrier that is orthogonal to each other is used. , Instruct slave stations 1A to 1C.

As shown in FIG. 16, in this example, the slave stations 1A and 1B transmit data to t11 immediately after the power stop is detected according to the instruction of the master station 2, and then the slave station 1C sends the slave station 1B to t12. And the data of the slave station 1C are multiplexed and transmitted. By providing the slave station 1C with the relay function according to the present embodiment, communication can be realized in a shorter time than in the comparative example of FIG. Here, the relay station can be provided with the same power stop notification timing determination function as the master station, and the notification timing of the slave station under the relevant relay station can be managed.

As described above, the function of the relay station may be provided in addition to the configuration of the first embodiment. Since the slave station is provided with the function of a relay station, the power stop of other slave stations can be multiplexed and notified to the master station, so that the power stop can be notified more efficiently and reliably.

(Embodiment 3)
Hereinafter, the second embodiment will be described with reference to the drawings. In the present embodiment, an example in which the master station in the first and second embodiments includes a plurality of antennas will be described.

FIG. 17 shows the configuration of the wireless communication system according to the present embodiment. As shown in FIG. 17, in the present embodiment, the master station 2 includes two antennas 32A and 32B. Here, the communication signal using the antenna 32A and the communication signal using the antenna 32B are signals using frequency bands, polarizations, and codes that do not interfere with each other. In the present embodiment, the master station 2 instructs the slave station of frequency band, polarization, and code information in addition to the power stop notification timing or by including the power stop notification timing. Each slave station 1 uses the frequency band, polarization, and code according to the instruction of the master station 2, and notifies the power stop at a designated timing. In the present embodiment, the master station 2 may determine the notification timing of each slave station 1 in consideration of the number of antennas of the master station 2.

FIG. 18 shows a network configuration example of a comparative example, and FIG. 19 shows a network configuration example according to the present embodiment. The network configurations of FIGS. 18 and 19 include a master station 2 and slave stations 1A to 1D, and are a master station 2 and a slave station 1A, a master station 2 and a slave station 1B, a master station 2 and a slave station 1C, and a master station. Communication is performed between 2 and the slave station 1D, respectively. The slave stations 1A to 1D are supplied with the same power supply from the power supply 3, and when the power supply stop from the power supply 3 is detected, the power supply is stopped at the frequency band and the instruction timing instructed in advance by the master station 2. Is notified to the master station 2.

FIG. 20 is a communication timing diagram of a comparative example in the network configuration of FIG. FIG. 20 shows a state in which the slave station 1B reaches the limit time during which backup communication is possible (time during which backup communication is possible) and a communication timeout occurs. That is, the slave station 1A and the slave station 1C transmit data to t13 immediately after the power is stopped according to the instruction of the master station 2. The slave station 1A transmits data via the antenna 32A, and the slave station 1C transmits data via the antenna 32B. After that, the slave station 1B and the slave station 1D transmit data at the timing t14. The slave station 1B transmits data via the antenna 32A, and the slave station 1D transmits data via the antenna 32B. At this time, the backup communication available time has passed during the transmission of the slave station 1B, and the data transmission is stopped.

On the other hand, in the present embodiment, the master station 2 gives an instruction to change the transmission signals and timings of the slave station 1B and the slave station 1C in advance from the backup communication available time, and constructs the network shown in FIG. FIG. 21 is a timing diagram according to the present embodiment in the network configuration of FIG. As shown in FIG. 21, the slave station 1A and the slave station 1B transmit data to t15 immediately after the power is stopped according to the instruction of the master station 2. The slave station 1A transmits data via the antenna 32A, and the slave station 1B transmits data via the antenna 32B. After that, the slave station 1C and the slave station 1D transmit data at the timing t16. The slave station 1C transmits data via the antenna 32A, and the slave station 1D transmits data via the antenna 32B. By setting the transmission timing of the slave station 1B earlier than that in FIG. 20 in this way, it is possible to normally notify the master station 2 before the backup communication available time has passed.

As described above, in the configurations of the first and second embodiments, the master station may have a plurality of antennas, and each antenna may receive a power stop notification from the slave station. As a result, it is possible to more efficiently and surely notify the power stop.

The present disclosure is not limited to the above embodiment, and can be appropriately modified without departing from the spirit.

Each configuration in the above-described embodiment is composed of hardware and / or software, and may be composed of one hardware or software, or may be composed of a plurality of hardware or software. The function (processing) of each device may be realized by a computer having a CPU, a memory, or the like. For example, a program for performing the method in the embodiment (control method of the wireless communication device or the control method of the wireless collection device) is stored in the storage device, and each function is executed by the CPU in the program stored in the storage device. It may be realized by.

These programs can be stored and supplied to a computer using various types of non-transitory computer readable media. Non-transitory computer-readable media include various types of tangible storage media. Examples of non-temporary computer-readable media include magnetic recording media (eg, flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (eg, magneto-optical disks), CD-ROMs (Read Only Memory), CD-Rs. CD-R / W, semiconductor memory (for example, mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (random access memory)) are included. The program may also be supplied to the computer by various types of transient computer readable media. Examples of temporary computer-readable media include electrical, optical, and electromagnetic waves. The temporary computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.

1 Slave station 2 Master station 3 Power supply 4 Relay station 5, 6 Wireless communication system 11 Backup power supply unit 12 Backup communication available time determination & notification unit 13 Power supply stop detection unit 14 Power supply stop notification timing control unit 15 Wireless transmission unit 16 Wireless reception unit 17 Power stop detection multiplex unit 21 Wireless reception unit 22 Wireless transmission unit 23 Power stop notification extraction unit 24 Power stop notification timing determination unit 31, 32 Antenna 100 Wireless communication device 101 Calculation unit 102 Notification unit 103 Notification unit 110 Wireless collection device 111 Determination Unit 112 Indicator 120 Wireless communication system 201 Transmission line 202 Communication area

Claims (15)

A calculation unit that calculates the power outage operation time during which communication operation is possible when the power is stopped,
A notification unit that notifies the wireless collection device of the calculated power failure operation time, and
When the power outage is detected, a notification unit that notifies the wireless collection device of the power outage at the power failure notification timing instructed by the wireless collection device according to the power failure operation possible time, and a notification unit.
A wireless communication device. The power failure operation time is
It is the time during which the notification can be made by the backup power supply when the power supply is stopped.
The wireless communication device according to claim 1. The power failure report timing is
This is the timing from the power stop to the elapsed power failure operation time.
The wireless communication device according to claim 1 or 2. Based on the power failure operation time notified from the wireless communication device, a determination unit that determines the power failure notification timing when the power of the wireless communication device is stopped, and a determination unit.
An instruction unit that instructs the wireless communication device of the determined power failure notification timing, and
A wireless collector equipped with. The power failure operation time is
It is the power outage operation time of multiple wireless communication devices.
The decision unit
Based on the comparison result of the power failure operation time of the plurality of wireless communication devices, the power failure notification timing of the plurality of wireless communication devices is determined.
The wireless collection device according to claim 4. The decision unit
The power failure report timing is determined so that the wireless communication device having a short power failure operation time can give priority to the report.
The wireless collection device according to claim 5. The decision unit
The power failure notification timing is determined by including the frequency band, polarization, or code information used by the wireless communication device for notification.
The wireless collection device according to claim 5 or 6. The decision unit
The power failure notification timing is determined based on the number of antennas included in the wireless collecting device or the number of other wireless communication devices relayed by the wireless communication device.
The wireless collecting device according to any one of claims 5 to 7. The wireless communication device according to any one of claims 1 to 3, and a plurality of wireless communication devices.
The wireless collecting device according to any one of claims 4 to 8.
A wireless communication system consisting of. The method for controlling a wireless communication device according to any one of claims 1 to 3. The method for controlling a wireless collecting device according to any one of claims 4 to 8. The control method for a wireless communication system according to claim 9. A control program comprising causing a computer to function as the wireless communication device according to any one of claims 1 to 3. A control program comprising causing a computer to function as the wireless collecting device according to any one of claims 4 to 8. The control program for a wireless communication system according to claim 9.

Images