WO2016189995A1

WO2016189995A1 - Communication system, smart meter, gateway device, and communication program

Info

Publication number: WO2016189995A1
Application number: PCT/JP2016/062009
Authority: WO
Inventors: 肇夫西田; 雅一白川
Original assignee: 株式会社東芝
Priority date: 2015-05-26
Filing date: 2016-04-14
Publication date: 2016-12-01
Also published as: JP6570879B2; JP2016220155A

Abstract

Provided are a communication system, a smart meter, a gateway device, and a communication program, with which it is possible to ensure communication between the gateway device, which in order to conserve power consumption may not always be started up, and the smart meter, which is always started up. The present invention has: asynchronous communication units 141, 231, with which a first relay unit 140 of the smart meter 100 and a second relay unit 230 of the gateway device can communicate in an asynchronous mode, in which normal communication is possible, between the gateway device 200 and the smart meter 100; synchronization control units 143, 233 for establishing and maintaining synchronization by transmitting and receiving synchronization signals and synchronization confirmation signals between the gateway device 200 and the smart meter 100; and synchronization communication units 144, 234 for communicating between the gateway device 200 and the smart meter 100 in a startup state and in a synchronization mode for communicating at a prescribed timing conforming to the established synchronization.

Description

Communication system, smart meter, gateway device, and communication program

Embodiments of the present invention relate to, for example, a communication system, a smart meter, a gateway device, and a communication program that connect a network that acquires data from the outside and another network.

The smart meter communication device regularly transmits meter reading data such as the power consumption of each consumer to the outside. The transmission destination of meter reading data from the communication device is a head end system (hereinafter referred to as HES). The HES is called a line concentrator and manages meter reading data from a large number of smart meters. The HES has a function of transmitting various commands and remotely controlling the smart meter. For example, there are a command for resetting the communication device remotely and a command for downloading software. There is also a command for requesting retransmission when periodic meter reading data is not received, and a command for forcibly turning off the power when the resident is absent.

JP 2011-61690 A

As described above, the smart meter communication device periodically transmits meter reading data. For example, there is a mode in which meter reading data is transmitted every 30 minutes to a computer of a meter data management system (hereinafter referred to as MDMS). A network that transmits meter reading data to the outside in this way is called an A route. A network that transmits / receives meter reading data to / from a management device provided in the house is called a B route.

Furthermore, in the future, it is preferable to perform energy management based on more diverse data by connecting a network that collects data other than power to such a network related to transmission and reception of power meter reading data. An example of such a network is a sensor network in which terminals with sensors that detect various parameters are connected to each other. In this case, the smart meter needs to receive these data from the network and transmit various commands for operating devices connected to the network to the network.

However, there are devices that cannot be activated at all times, such as smart meters, among communication devices that constitute a network that collects other data. For example, there is a case where a gateway device serving as a window of a network for collecting data is battery-powered, and the CPU is activated at regular intervals to transmit / receive data only during activation in order to save power consumption. .

Then, even if the smart meter is always activated for communication on the A route side, there are cases where the timing of data transmission / reception cannot be synchronized. In particular, even if the smart meter tries to send a command, it cannot be sent if the gateway device is not activated.

Furthermore, in the wireless multi-hop method, when the smart meter switches between a plurality of channels and communicates with other smart meters, the channel being used cannot be used for communication with the gateway device. For this reason, communication is not possible even if the gateway device is activated.

The embodiments of the present invention have been proposed to solve the above-described problems of the prior art, and the purpose thereof is a gateway that is not always activated to save power consumption. An object of the present invention is to provide a communication system, a smart meter, a gateway device, and a communication program that can ensure communication between a device and a smart meter that is always activated.

A communication system according to an embodiment of the present invention has been proposed in order to achieve the above-described object, and includes a first connection unit that performs connection with a power supply that constantly supplies power, and detection from the outside. A detection data acquisition unit that acquires data; a first communication unit that transmits and receives detection data acquired by the detection data acquisition unit via a first network; and a first relay unit that connects to a relay network; , Having a smart meter. In the present embodiment, the second connection unit that connects to a constant-capacity power source, the second communication unit that communicates via a second network, and the first network via the relay network Sleep in which the second relay unit connected to the relay unit, the second communication unit, and the second relay unit are in a start-up state in which power consumption is high and communication is possible, or power consumption is low and communication is not performed And a start-up control unit that controls whether to enter a state.

Furthermore, the first relay unit and the second relay unit include an asynchronous communication unit that performs communication in an asynchronous mode in which communication is always possible between the gateway device and the smart meter, and the gateway device and the smart meter. The synchronization control unit that establishes and maintains synchronization by transmitting and receiving a synchronization signal and a synchronization confirmation signal between the gateway device and the smart meter, and is in the activated state and established synchronization And a synchronous communication unit that performs communication in a synchronous mode in which communication is performed at a predetermined timing according to the standard.

In addition, as another aspect, it can also be grasped as a program for causing a computer to execute the functions of the above-described units. Moreover, it can also be comprised as a smart meter and gateway apparatus which have said each part as another aspect.

1 is a configuration diagram of a communication system to which an embodiment is applied. It is a block diagram which shows a smart meter and a gateway apparatus. It is a block diagram which shows a 1st relay part and a 2nd relay part. It is a sequence diagram which shows the establishment process of a synchronization. It is a sequence diagram which shows an intermittent window process. It is a sequence diagram which shows an extended window process. It is a sequence diagram which shows the return process from a synchronization loss. It is a sequence diagram which shows the downlink communication in channel switching communication. It is a sequence diagram which shows the resending process of downlink communication. It is a sequence diagram which shows the uplink communication in channel switching communication. It is a sequence diagram which shows the resending process of uplink communication. It is a sequence diagram which shows the resending process of uplink communication. It is a sequence diagram which shows channel control.

[Configuration of the embodiment]
[Overview]
First, FIG. 1 shows a configuration example of the communication system S of the present embodiment. The communication system S includes a smart meter 100 and a gateway device 200 that are connected via a relay network N3. Information communicated by the communication system S includes various data and commands.

Smart meter 100 is, for example, a power meter. Each smart meter 100 is installed in each customer C. The smart meter 100 is a device that collects detection data of each customer C and transmits it to the outside. The detection data is data related to power, and includes, for example, the power usage of each customer C. The detection data is detected by the detection device. The detection device includes a current sensor and a voltage sensor connected to the power equipment of each customer C. The detection data includes the detection value itself and data calculated based on the detection value. A communication path for collecting detection data in this way is called a B route. The B route includes a HEMS (Home Energy Management System) 700. The HEMS 700 is a system that collects and controls the power consumption of individual power consuming devices in each customer C.

The smart meter 100 is connected to a power management system via a first network N1, a WAN (Wide Area Network) 400, and the like. As the first network N1, for example, a public network such as 3G / LTE, wireless multi-hop using a 920 MHz band, PLC using a power line, or the like can be applied. Note that the first network N1 constitutes a communication path called A route in a general smart meter communication system.

As the WAN 400, for example, a public network such as an optical line or 3G / LTE can be used. As systems for managing power, there are HES (Head end system) 500 and MDMS (Meter Data System) 600. The HES 500 is a server group that collects detection data from a large number of smart meters 100 and centrally manages them. The HES 500 transmits / receives information to / from an MDMS (Meter Data Management System) 600. The MDMS 600 is a system that analyzes detection data collected from the smart meter 100 and provides information regarding efficient energy use to the customer C, such as setting of a power charge.

The gateway device 200 is a device that collects various data via the second network N2. The second network N2 is a network different from the first network N1 constituting the A route. Data collected via the second network N2 may be data related to power or data other than power. An example of the second network N2 is a sensor network including the above-described sensor as a node. The gateway device 200 relays various commands transmitted from the first network N1 and used to operate devices connected to the second network N2.

The smart meter 100 and the gateway device 200 transmit and receive data via the relay network N3. That is, the gateway device 200 is a communication device that connects different networks. The data transmitted / received via the relay network N3 may be data related to power or data other than power. The above commands are also sent and received.

The smart meter 100 and the gateway device 200 can be realized by controlling a computer such as a microprocessor including a CPU, a memory, an interface, and the like with a predetermined program. That is, the following processing units are configured by the CPU executing a program read from the memory at the time of startup. The program in this case implements various processes shown below by physically utilizing computer hardware. For this reason, the following description uses a functional block diagram in which functions for realizing various processes are virtually blocked.

Even if a common CPU, memory, and the like operate, functions that can be considered as separate processing units are shown in separate blocks. For example, regarding communication processing, functions for performing processing based on different protocols and functions for connecting to different networks are regarded as separate processing units.

However, how to set the range to be processed by hardware and the range to be processed by software including a program is not limited to a specific mode. For example, any of the processing units described below can be configured as a circuit that realizes each processing.

Furthermore, a method, a program, and a recording medium storing the program for executing processing of each processing unit described below are also one aspect of the embodiment.

[Smart meter configuration]
As illustrated in FIG. 2, the smart meter 100 includes a first connection unit 110, a detection data acquisition unit 120, a first communication unit 130, and a first relay unit 140.

[First connection section]
The first connection unit 110 is a processing unit that performs connection with a power supply that constantly supplies power. The first connection unit 110 supplies power from the connected power source to the smart meter 100. For example, the first connection unit 110 is connected to an AC power supply via an AC power line. In this case, the first connection unit 110 includes an AC / DC conversion circuit, a regulator, and the like.

[Detection data acquisition unit]
The detection data acquisition unit 120 is a processing unit that acquires detection data from the outside. The detection data acquisition part 120 is connected to the detection part which detects the data of the electric power equipment of each consumer C. The detection unit includes a current sensor that measures current, a detection device such as a voltage sensor that measures voltage, a power calculation unit that calculates power usage from detection data, and the like. The detection data acquisition unit 120 controls the arrangement and storage of the detection data input from the detection unit.

Note that the detection data acquisition unit 120 is a processing unit that performs communication via the B route communication path. For this reason, the detection data acquisition part 120 may be made to be able to transmit / receive various commands between the electric power equipment of each customer C, HEMS, etc.

[First communication unit]
The first communication unit 130 is a processing unit that transmits and receives the detection data acquired by the detection data acquisition unit 120 via the first network N1. That is, the first communication unit 130 is a processing unit that performs communication via the communication route of the A route. For this reason, the first communication unit 130 transmits and receives data and commands by various protocols applied according to the first network N1, for example, programs according to 3G / LTE, wireless multi-hop, and PLC. Can do.

[First relay section]
The first relay unit 140 is a processing unit that connects to the relay network N3. The first relay unit 140 transmits / receives information to / from the gateway device 200 via the relay network N3. Information transmitted / received includes commands from the smart meter 100, data collected by the gateway device 200, and the like. Although not shown, the first relay unit 140 includes a channel setting unit that sets a channel used for communication with the first network N1. This channel setting unit sets one specific channel when there are a plurality of usable channels. For example, when wireless multi-hop communication is performed, a channel that periodically arrives is used for communication with each smart meter 100 among a plurality of channels. The channel setting unit sets such a channel.

The first relay unit 140 includes an asynchronous communication unit 141, a channel setting unit 142, a synchronization control unit 143, and a synchronous communication unit 144. The asynchronous communication unit 140 is a processing unit that performs communication in an asynchronous mode in which communication with the gateway device 200 is always possible. The asynchronous communication unit 140 performs communication in the asynchronous mode when the synchronization control unit 143 cannot receive the synchronization confirmation signal.

The channel setting unit 142 is a processing unit that sets a specific channel as a channel used for communication with the gateway device 200. For example, the channel setting unit 142 sets one specific channel when there are a plurality of usable channels. This channel may be configured to use a channel different from the channel used by the first communication unit 130 for communication, or the same channel may be used.

In addition, the channel setting part 142 can set one channel which comes periodically among several channels as a channel used for communication. That is, when the first communication unit 130 uses a plurality of channels by periodically switching it, the first communication unit 130 can use it only during a time period when the channel is not used. In this case, the channel setting unit 142 sets the channel that is not used by the first communication unit 130 among any one of the channels that arrive periodically, or the same channel on the assumption that the time zone is used separately. Set. Thus, the channel used for communication with the gateway apparatus 200 is called a home channel. In this case, the home channel also arrives periodically.

The synchronization control unit 143 is a processing unit that establishes and maintains synchronization with the gateway apparatus 200 by transmitting and receiving a synchronization signal and a synchronization confirmation signal. As shown in FIG. 3, the synchronization control unit 143 includes a synchronization setting unit 143a, a synchronization establishment unit 143b, a retransmission control unit 143c, and a correction unit 143d.

The synchronization setting unit 143a is a processing unit that sets the synchronization signal including the start timing of the intermittent window, the duration of the intermittent window, and the number of times the intermittent window is repeated. The intermittent window secures a communication circuit for a certain time so that data can be transmitted and received in a predetermined unit.

The synchronization establishment unit 143b is a processing unit that establishes synchronization with the gateway device 200 based on the setting content set by the synchronization setting unit 143a. More specifically, the synchronization establishment unit 143b establishes synchronization by transmitting the synchronization signal set by the synchronization setting unit 143a and receiving the synchronization confirmation signal.

The retransmission control unit 143c is a processing unit that controls retransmission of a synchronization signal or data when synchronization cannot be established or data cannot be transmitted. For example, if the synchronization signal can be retransmitted in the same intermittent window as the intermittent window in which the synchronization confirmation signal for the synchronization signal could not be received, the retransmission control unit 143c retransmits the intermittent signal in the intermittent window. When the window has passed, retransmission is performed in the subsequent intermittent windows.

The correction unit 143d is a processing unit that corrects the start timing of the next intermittent window by adding or subtracting a predetermined offset value to or from the transmission time or reception time of the synchronization signal. For example, in the case of retransmission by the retransmission control unit 143c, the correction unit 143d corrects the start timing of the next intermittent window.

The synchronous communication unit 144 is a processing unit that communicates with the gateway device 200 in a synchronous mode in which the gateway device 200 is in an activated state and communicates at a predetermined timing according to the established synchronization.

The synchronous communication unit 144 includes an intermittent communication unit 144a and an extended communication unit 144b. The intermittent communication unit 144a is a processing unit that performs communication by an intermittent window that opens at predetermined intervals according to established synchronization. The extended communication unit 144b is a processing unit that transmits and receives data using an extended window that collectively transmits and receives data that exceeds the amount of data that can be received in one intermittent window.

[Gateway device configuration]
As illustrated in FIG. 2, the gateway device 200 includes a second connection unit 210, a second communication unit 220, a second relay unit 230, an activation control unit 240, an activation setting unit 250, and an accumulation unit 260.

[Second connection section]
The second connection unit 210 is a processing unit that performs connection with a constant-capacity power source. The second connection unit 210 supplies power from the power source to the gateway device 200. The power source connected to the second connection unit 210 is a battery. The battery includes a primary battery and a secondary battery.

[Second communication section]
The second communication unit 220 is a processing unit that communicates via the second network N2. In order for the second communication unit 220 to transmit and receive data via the second network N2, it is necessary to perform the activation control unit 240 described later at a timing when the gateway device 200 is activated.

[Second relay unit]
The second relay unit 230 is a processing unit connected to the first relay unit 140 of the smart meter 100 via the relay network N3. The second relay unit 230 includes an asynchronous communication unit 231, a channel setting unit 232, a synchronization control unit 233, and a synchronous communication unit 234. The asynchronous communication unit 231 is a processing unit that performs communication in an asynchronous mode in which communication with the smart meter 100 is always possible. Further, the asynchronous communication unit 231 performs communication in the asynchronous mode when the synchronization control unit 233 of the second relay unit 230 cannot receive the synchronization signal.

The channel setting unit 232 is a processing unit that sets a specific channel as a channel used for communication with the smart meter 100. This channel is, for example, a specific channel on the smart meter 100 side. That is, it is adjusted to a specific channel set by the channel setting unit 142 of the smart meter 100.

In addition, the channel setting part 232 can set one channel which comes periodically among several channels as a channel used for communication. When the first communication unit 130 of the smart meter 100 periodically uses a plurality of channels, the channel set by the channel setting unit 232 is a home channel.

The synchronization control unit 233 is a processing unit that establishes and maintains synchronization with the smart meter 100 by transmitting and receiving a synchronization signal and a synchronization confirmation signal. As shown in FIG. 3, the synchronization control unit 233 includes a synchronization setting unit 233a, a synchronization establishment unit 233b, a retransmission control unit 233c, and a correction unit 233d.

The synchronization setting unit 233a is a processing unit that sets the intermittent window start timing, the intermittent window duration, and the number of times the intermittent window is repeated based on the synchronization signal received from the smart meter 100. As described above, the intermittent window is a buffer that ensures that data can be transmitted and received in a predetermined unit.

The synchronization establishment unit 233b is a processing unit that establishes synchronization with the smart meter 100 based on the setting content set by the synchronization setting unit 233a. More specifically, the synchronization establishment unit 233b establishes synchronization by receiving a synchronization signal and transmitting a synchronization confirmation signal corresponding thereto.

The retransmission control unit 233c is a processing unit that controls retransmission of a synchronization confirmation signal or data when synchronization cannot be established or data cannot be transmitted. For example, when retransmission is possible within the same intermittent window as the intermittent window for which the synchronization confirmation signal could not be transmitted, the retransmission control unit 233c retransmits within the intermittent window, and when the intermittent window has elapsed Then, retransmission is performed in the next intermittent window.

The correction unit 233d is a processing unit that corrects the start timing of the next intermittent window by adding or subtracting a predetermined offset value to or from the transmission time or reception time of the synchronization signal. For example, the correction unit 233d corrects the start timing of the next intermittent window when the retransmission of the synchronization signal is performed by the retransmission control unit 143c of the first relay unit 140.

The synchronous communication unit 234 is a processing unit that communicates with the smart meter 100 in a synchronous mode in which the gateway device 200 is in an activated state and communicates at a predetermined timing according to established synchronization.

The synchronous communication unit 234 includes an intermittent communication unit 234a and an extended communication unit 234b. The intermittent communication unit 234a is a processing unit that performs communication using an intermittent window that opens at predetermined intervals according to established synchronization. The extended communication unit 234b is a processing unit that transmits and receives data using an extended window that collectively transmits and receives data exceeding the amount of data that can be received in one intermittent window.

[Startup control unit]
The activation control unit 240 sets the gateway device 200, that is, the second communication unit 220 and the second relay unit 230 to an activation state in which power consumption is high and communication is possible, or a sleep state in which power consumption is low and communication is not performed. It is a processing unit that controls whether to do. The sleep state widely includes a state in which power consumption is suppressed in order to save battery power.

[Startup setting section]
The activation setting unit 250 is a processing unit that sets an activation condition as to whether the activation control unit 240 is to be activated or sleep. For example, the activation setting unit 250 sets in advance the timing for receiving data from the second network N2. When this timing arrives, when the activation control unit 240 activates the gateway device 200 and receives data, the activation control unit 240 enters the sleep state again. This timing is not related to the timing of the intermittent window.

For example, in the activation setting unit 250, the activation control unit 240 is activated in order for the second communication unit 220 to receive information, the next predetermined timing has arrived, and the accumulation unit 260 described later accumulates. Until the information is transmitted, the activation condition by the activation control unit 240 is set so as to continue the activation state.

In addition, the activation setting unit 250 has entered the sleep state until the next predetermined timing comes after the activation control unit 240 has entered the activation state in order for the second communication unit 220 to receive information. In this case, the activation condition by the activation control unit 240 is set so that the information accumulated by the accumulation unit 260 is transmitted as the activation state.

[Storage unit]
The accumulation unit 260 is a processing unit that accumulates data received until the next predetermined timing after the activation control unit 240 is in an activated state so that the second communication unit 220 receives information. The predetermined timing here is a timing of an intermittent window for performing communication in the synchronous mode.

The smart meter 100 and the gateway device 200 have a storage unit. The storage unit is a processing unit that stores various types of information necessary for processing of the smart meter 100 and the gateway device 200. A semiconductor memory or the like can be used as the storage unit. A storage medium that is detachable from the smart meter 100 and the gateway device 200 may be configured as a storage unit.

The storage unit includes a main memory for storing programs and the like, a cache memory used as a temporary storage area, a buffer memory, a register, and the like. Storage area for information such as data and commands input via the detection device, the first network N1, the second network N2, and the relay network N3, and a storage area for absorbing differences in processing timing among the units Can also be regarded as a storage unit.

The information stored in the storage unit includes information generated by each unit of the smart meter 100 and the gateway device 200 in addition to the above data and commands. Various settings such as a channel, timing, synchronization signal, activation condition, ID, authentication key, and timeout time are also included in the information stored in the storage unit.

Furthermore, the smart meter 100 and the gateway device 200 have a system time setting unit for setting a system time indicating the current time. For example, when the program is started, the system time is set on the memory with reference to the built-in hardware clock. This system time becomes a time information source of the smart meter 100 and the gateway device 200.

The system time setting unit adjusts the time at a predetermined timing. For example, the system time is synchronized once a day by SNTP (Simple network time protocol). Further, the system time setting unit can also synchronize even when the system time is determined not to be large and effective due to the SNTP. The synchronized time may be reflected in the hardware clock.

[Action]
The operation of the present embodiment as described above will be described with reference to FIGS. In the figure, SM is the smart meter 100, and GW is the gateway 200.
(Establishing synchronization)
First, the process for establishing synchronization will be described with reference to FIG. The smart meter 100 is basically activated at all times, and the asynchronous communication unit 141 in the first relay unit 140 is in a state where it can always communicate with the outside. When the gateway device 200 is activated, the asynchronous communication unit 231 of the second relay unit 230 is in a state where it can always communicate with the outside. However, the smart meter 100 and the gateway device 200 are in a state of not recognizing each other when the gateway device 200 is activated.

From this state, the asynchronous communication unit 141 and the asynchronous communication unit 231 perform connection authentication with each other. For this connection authentication, for example, PANA can be used. That is, the asynchronous communication unit 231 transmits an extended beacon request (EBR: Enhanced Beacon Req). In the storage unit of each smart meter 100, an ID for identifying the gateway device 200 given from the system for managing power is registered. This ID is an ID that identifies which gateway device 200 is to communicate with. The authentication key and the like are also registered in the storage unit of the smart meter 100.

Among the many smart meters 100, the asynchronous communication unit 231 of the smart meter 100 that registers the ID included in the extended beacon request (EBR) transmitted from the gateway device 200 side transmits the extended beacon to the gateway device 200. To do. That is, any one of the plurality of smart meters 100 is in a position to communicate with the gateway device 200.

Note that when the first communication unit 130 in the smart meter 100 performs communication while periodically switching a plurality of channels by wireless multi-hop or the like, the

channel setting units

142 and 232 set the home channel. That is, the channel setting unit 142 of the smart meter 100 waits on a specific channel that is not used by the first communication unit 130. Alternatively, it is possible to wait on the same channel as the channel used by the first communication unit 130 by preventing the use time from overlapping. The channel setting unit 232 of the gateway device 200 switches the channel and searches sequentially until there is a response to the EBR. When there is a response, the channel setting unit 232 sets the channel as the home channel.

The asynchronous communication unit 231 of the gateway device 200 that has received the extended beacon as a response to the extended beacon request (EBR) exchanges PCI, PAR, and PAN signals with the asynchronous communication unit 141 of the smart meter 100 that has transmitted the extended beacon. Thus, connection authentication is performed and the encryption key is shared. In this way, the smart meter 100 communicating with the gateway device 200 is determined on a one-to-one basis.

The synchronization establishment unit 143b in the smart meter 100 transmits a synchronization signal to the determined gateway device 200. The synchronization establishment unit 233b in the gateway device 200 transmits a synchronization confirmation signal to the smart meter 100. The synchronization establishment unit 233b of the gateway device 200 that has transmitted the synchronization confirmation signal and the synchronization establishment unit 143b of the smart meter 100 that has received the synchronization confirmation signal start synchronous communication with the smart meter 100 with the contents set by the synchronization signal. That is, the asynchronous mode is changed to the synchronous mode. Messages after the establishment of synchronization are encrypted at the MAC layer.

(Intermittent window control)
FIG. 5 illustrates a process in which the intermittent communication unit 144a of the smart meter 100 and the intermittent communication unit 234a of the gateway device 200 perform intermittent communication in the downward direction from the smart meter 100 to the gateway device 200 after the synchronization is established as described above. The description will be given with reference. Basically, the smart meter 100 is always activated. Therefore, uplink communication from the gateway device 200 to the smart meter 100 can be transmitted at any time when the gateway device 200 is activated. That is, after synchronization is established, bidirectional transmission in the upstream and downstream directions is possible.

The intermittent communication unit 144a of the smart meter 100 opens an intermittent window of several hundred milliseconds every few seconds after synchronization is established. This intermittent window is a transmission window for transmission. In addition, the intermittent communication unit 234a of the gateway device 200 opens a slightly longer intermittent window at the same interval as the intermittent window from the synchronization establishment time. This intermittent window is a reception window for reception. The reason for the longer time on the receiving side is to absorb a timing shift due to a clock error between the smart meter 100 and the gateway device 200.

The intermittent communication unit 144a of the smart meter 100 transmits information such as downlink data or commands during the time when the transmission window and the reception window are open. When receiving intermittent data, the intermittent communication unit 234a of the gateway device 200 transmits a response message such as MAC ACK. Such transmission / reception between the smart meter 100 and the gateway device 200 is repeated each time a transmission window and a reception window arrive.

The intermittent communication unit 144a of the smart meter 100 holds the data in the storage unit while waiting for transmission while the transmission window is closed. The activation control unit 240 of the gateway device 200 saves the battery as a power source by setting the sleep state while the reception window is closed.

The CPU clocks of the smart meter 100 and the gateway device 200 are slightly different. For this reason, when time elapses from the start of synchronous communication, a shift that is out of synchronization occurs. Therefore, the synchronization establishment unit 143b of the smart meter 100 and the synchronization establishment unit 233b of the gateway device 200 maintain synchronization by exchanging the synchronization signal and the synchronization confirmation signal at a constant period of about several minutes to 10 minutes.

(Extended window processing)
In the intermittent communication as described above, only a certain unit of data can be transmitted every few seconds when the transmission window and the reception window are opened. A case where extended communication is performed during synchronous communication will be described with reference to FIG. The first communication unit 130 of the smart meter 100 transmits a block data request with a flag indicating that block data including a plurality of units of data is going to be transmitted as the downlink data 1, and the downlink data 2 is the block data. Send a generic message.

Then, the extended communication unit 144b of the smart meter 100 transmits a block data request to the gateway 200 and opens an extended window. This extended window is a continuous transmission window. When the extended communication unit 234b of the gateway device 200 receives the block data request, it opens an extended window so that it can always be received. This extended window is a continuous reception window. That is, the extended communication unit 144b and the extended communication unit 234b perform window control ignoring the timing of the transmission window and reception window of intermittent communication.

The extended communication unit 144b transmits a general-purpose message indicating the end of the block data. When the transmission is finished, the extended communication unit 144b closes the extended window. The extended communication unit 234b of the gateway device 200 closes the extended window when receiving the general message that is the last of the block data. The activation control unit 240 of the gateway device 200 maintains the activation state while the continuous reception window is open. After the extended communication unit 144b of the smart meter 100 transmits a block data request, if a predetermined time elapses after the transmission of data is terminated, a timeout occurs and the intermittent communication unit 144a and the intermittent communication unit 234a return to intermittent communication. .

The blocking may be realized by an appropriate protocol between the smart meter 100 and the

extended communication units

144b and 234b of the gateway 200. For example, the blocking is performed in the MAC layer, the network layer, or the application layer. It is not limited.

(Return processing from out of sync)
The return process when the synchronization is lost will be described with reference to FIG. First, the out-of-synchronization detection process will be described. The synchronization establishment unit 143b of the smart meter 100 retransmits after several seconds if the synchronization confirmation cannot be received even though the synchronization signal is transmitted. If the synchronization establishing unit 143b does not receive the synchronization confirmation signal within a few seconds after the retransmission, the synchronization establishing unit 143b determines that the synchronization is lost and stops transmission of the synchronization signal.

Since the synchronization signal includes a period for receiving the synchronization signal, the synchronization establishment unit 233b of the gateway apparatus 200 determines that the synchronization has been lost when the synchronization signal cannot be received even if the period arrives a plurality of times. To do. For example, in FIG. 7, loss of synchronization is detected when reception is not possible twice.

Next, the re-drawing process for returning from the out-of-synchronization to the synchronized state will be described. The synchronization establishment unit 233b that has determined that the synchronization is lost transmits a synchronization request. For example, in FIG. 7, a synchronization request based on the current PANA session information is transmitted. Since the smart meter 100 is always activated as described above, the synchronization establishment unit 143b can receive it whenever the synchronization establishment unit 233b transmits a synchronization request.

The asynchronous communication unit 231 of the gateway device 200 performs asynchronous communication. That is, the continuous reception waiting state in which the reception of the synchronization signal is continuously waited for a predetermined time is repeated a plurality of times to wait for the synchronization signal. Within this time, the synchronization establishment unit 143b of the smart meter 100 may transmit a synchronization signal corresponding to the synchronization request. In this case, when the synchronization establishment unit 233b of the gateway apparatus 200 receives the transmitted synchronization signal and transmits a synchronization confirmation signal, synchronization is established again and intermittent communication is resumed. Therefore, after that, synchronous communication resumes.

However, if the synchronization signal cannot be received due to this, the synchronization establishment unit 233b of the gateway device 200 transmits a synchronization request with the new PANA session information. Then, the synchronization is established again after receiving the synchronization signal from the synchronization establishment unit 143b of the smart meter 100 and the transmission of the synchronization confirmation signal from the synchronization establishment unit 233b of the gateway device 200. After that, synchronous communication resumes.

(Downlink communication for channel switching communication)
Next, processing in the case of channel switching communication will be described with reference to FIGS. 8 to 12, the upper row shows opening and closing of the reception window along the time axis of the smart meter 100. The lower part shows the transition of the reception window (upper side) along the time axis of the gateway device 200 and the activation state (lower side) for transmission. Since smart meter 100 is always activated, transmission can be performed at a timing that matches the reception window of gateway device 200 regardless of its own reception window.

The above example is a case where communication in the A route among communication by the first communication unit 130 of the smart meter 100 is always connected like a line using a public network such as 3G / LTE. However, for example, when the first communication unit 130 uses wireless multihop as the A route, communication is performed while switching a plurality of channels by hopping.

In this case, as described above, the first relay unit 140 can use only the home channel for communication with the gateway device 200, but the first communication unit 130 uses this home channel. It is also possible to use channels. Since the home channel also arrives periodically, the timing at which data can be transmitted arrives intermittently. For this reason, the first relay unit 140 of the smart meter 100 is not always able to receive data because of the relationship with the gateway device 200, and performs intermittent communication.

For example, when the smart meter 100 is communicating with the

channels

1, 2, 3,..., The

channels

2 and 3 are used for communication with other smart meters 100. In this case, if the gateway device 200 is set to use channel 1 fixedly, communication cannot be performed on the second and third channels.

In order to determine the home channel used for communication with the smart meter 100, the asynchronous communication unit 141 of the gateway device 200 transmits an extended beacon request while changing the channel. As for the channel to be switched, the same channel returns at regular intervals. When the asynchronous communication unit 141 of the smart meter 100 receives an extended beacon request on the home channel, communication on the home channel is determined by transmitting the extended beacon. Subsequent connection authentication is as described above.

And as shown in FIG. 8, the synchronous establishment part 143b of the smart meter 100 transmits a synchronous signal to the gateway apparatus 200 for every fixed time Tsync. The synchronization signal includes information indicating when the smart meter 100 returns to the home channel.

This information is, for example, T0, T1, and N. T0 is the timing when the next home channel arrives. T0 takes a variable value for each transmission timing of the synchronization signal. T1 is a certain period when the home channel arrives. N is the number of times that the synchronization of the home channel returns is considered to be maintained. The number obtained by dividing the maximum number of seconds that can be communicated even if the clock is shifted by the channel period T1 is N. When N times are counted for each period T1, the maximum time during which synchronization can be maintained is reached. Then, since the information notified as T0 and T1 expires, the synchronization establishment unit 143b of the smart meter 100 transmits a new synchronization signal. After synchronization by a new synchronization signal, it is considered that synchronization is maintained until N times are counted.

The synchronization establishment unit 233b of the gateway device 200 that has received the synchronization signal transmits a synchronization confirmation signal at the next timing. Then, the intermittent communication unit 234 of the gateway device 200 opens the intermittent window for a predetermined time Tr every predetermined time Tp. This intermittent window is a reception window. When the reception window is open, the intermittent communication unit 144a of the smart meter 100 transmits data. A sync signal is also sent when the receive window is open. When the synchronization establishment unit 143b of the smart meter 100 cannot receive the synchronization confirmation, the retransmission control unit 143c retransmits the synchronization signal to the next reception window.

(Retransmission process in case of error)
About the retransmission processing when the synchronization establishment unit 143b on the smart meter 100 side generates a CCA (Clear Channel Assessment) error when transmitting a synchronization signal, or when a synchronization signal is transmitted but a MAC ACK reception error occurs. This will be described with reference to FIG. The CCA error is an error indicating that the channel is busy and data cannot be output in the free channel determination. The MAC ACK error is an error that data is transmitted but ACK that is a response from the transmission partner cannot be received.

If an error such as that described above occurs, the retransmission control unit 143c retransmits the synchronization signal if it can be retransmitted within the same reception window. If retransmission cannot be performed within the same reception window, retransmission is performed when the next reception window opens.

In any retransmission, the start timing of the reception window in the synchronization signal is corrected. First, when the synchronization establishing unit 233b in the gateway apparatus 200 receives a synchronization signal, the correction unit 233d recalculates and determines the start timing of the next reception window by adding or subtracting the offset value as follows.

The reception end timing of transmission data and the packet length including the header to be transmitted are known. The reception end timing of transmission data is the reception timing (time) of the last octet of transmission data. The packet length is the length of the PHY header (SHR, PHR) and the PHY payload (PSDU). A value obtained by adding a drift margin indicating a clock shift to the reception end timing and subtracting the packet length and the reception window interval Tp is obtained as the next reception window start timing. Similarly, when the synchronization establishment unit 143b in the smart meter 100 receives the synchronization confirmation signal, the correction unit 143d recalculates and determines the start timing of the next reception window.

(Uplink communication for channel switching communication)
A case where uplink communication from the gateway device 200 to the smart meter 100 is performed in the above-described channel switching communication will be described with reference to FIG. As described above, the synchronization establishment unit 143b of the smart meter 100 notifies the gateway device 200 of the timing of the home channel using the synchronization signal.

The activation control unit 240 of the gateway device 200 sets the gateway device 200 in an activated state so that the second communication unit 220 receives data from the second network N2 at a timing according to the setting of the activation setting unit 250. . At this time, in order to further transmit data to the smart meter 100, the activation control unit 240 waits in the activated state until the next home channel timing and transmits the data to the sleep state. Alternatively, the activation control unit 240 may be transmitted in the activated state at the timing of the next home channel after temporarily entering the sleep state. Details of the timing control of this aspect will be described later.

(Uplink retransmission control)
As shown in FIG. 11, the intermittent communication unit 234a of the synchronous communication unit 234 performs back-off with a waiting time even when transmitting uplink data, even in the case of initial transmission. The intermittent communication unit 234a further performs back-off when a carrier is detected on the relay network N3. Further, when the carrier is detected continuously, retransmission is performed at the timing of the next home channel. As shown in FIG. 12, even in the case of a MAC ACK error, retransmission is performed at the timing of the next home channel.

(Specific example of channel control)
Furthermore, a specific example of the above-described channel control will be described with reference to FIG. In the transmission methods 1 to 3, the upper stage shows the transition of the reception channel used by the smart meter 100 in time series. In the upper stage, each square is an individual reception channel. For example, it is assumed that the reception channel arrives at the home channel in a cycle of 20 channels. The other channels are any channels used by the first communication unit 130 in the A route. The use of any one of these channels and the cycle thereof are determined for each smart meter 100. The lower part shows the time series transition of the activation state and the sleep state of the gateway device 200.

First, in the transmission method 1, the activation control unit 240 of the gateway device 200 periodically activates the gateway device 200 and then enters a sleep state at a timing in accordance with the period at which the home channel of the smart meter 100 arrives. It is a method to repeat. For example, it starts at the timing of No. 1, No. 21, No. 41,. If there is data to be transmitted to the smart meter 100 at the time of startup, the data is transmitted. If there is no transmission data, no data is transmitted. In addition to the regular activation, the activation control unit 240 activates the gateway device 200 to receive data from the second network N2, and receives data. This timing is set in the activation setting unit 250 as a periodical reception timing of data from the second network N2 on the gateway device 200 side. The following activation conditions are also set in advance in the activation setting unit 250. The received data is accumulated in the accumulating unit 260, and then the activation control unit 240 enters a sleep state. The accumulated data is transmitted to the smart meter 100 at regular startup.

In the case of this transmission method 1, since the activation is intermittent, the power consumption of the power supply of the gateway device 200 can be saved. However, when there is little transmission data, there are many cases where there is no transmission even if it is activated.

Next, in the transmission method 2, the activation control unit 240 of the gateway device 200 does not periodically activate. Then, when the gateway device 200 is activated to receive data from the second network N2, the activation control unit 240 is in a sleep state after transmitting data to the smart meter 100 as being activated until the home channel timing. And In this case, it is necessary to wait for the activation to continue until data transmission to the smart meter 100, but since there is no periodic activation without data transmission, power consumption can be further saved. This is effective when the data is relatively small.

Furthermore, the transmission method 3 is the same as the transmission method 2 in that the activation control unit 240 of the gateway device 200 does not periodically activate. However, when the gateway device 200 is activated to receive data from the second network N2, the activation control unit 240 enters a sleep state after receiving the data. Then, the activation control unit 240 activates again when the timing of the next home channel arrives, transmits data to the smart meter 100, and again enters the sleep state. In this case, since it is not necessary to wait until the data is transmitted to the smart meter 100, power consumption can be further saved.

[effect]
(1) The communication system S of the present embodiment is acquired by the first connection unit 110 with a power supply that constantly supplies power, the detection data acquisition unit 120 that acquires detection data from the outside, and the detection data acquisition unit 120 The smart meter 100 includes a first communication unit 130 that transmits / receives the detected data via the first network N1 and a first relay unit 140 that connects to the relay network N3.

Further, the second connection unit 210 with a constant capacity power source, the second communication unit 220 communicating via the second network N2, and the first relay unit 140 via the relay network N3 are connected. Whether the second relay unit 230, the second communication unit 220, and the second relay unit 230 are in a start state in which power consumption is high and communication is possible, or in a sleep state in which power consumption is low and communication is not performed And a start-up control unit 240 that controls the gateway device 200.

Further, the first relay unit 140 and the second relay unit 230 include the

asynchronous communication units

141 and 231 that perform communication in the asynchronous mode in which communication is always possible between the gateway device 200 and the smart meter 100, and the gateway device 200. The

synchronization control units

143 and 233 that establish and maintain synchronization by transmitting and receiving a synchronization signal and a synchronization confirmation signal between the gateway device 200 and the smart meter 100 are in an activated state. And

synchronous communication units

144 and 234 that perform communication in a synchronous mode in which communication is performed at a predetermined timing according to established synchronization.

For this reason, the gateway device 200 does not communicate when the activation control unit 240 is in the sleep state, but communicates with the smart meter in the synchronous mode when it is in the activation state, thus saving power consumption of a constant capacity power supply, Communication between the gateway device 200 that is not always activated and the smart meter 100 that is always activated can be secured.

(2) The

synchronous communication units

144 and 234 in the first relay unit 140 and the second relay unit 230 have

intermittent communication units

144a and 234a that perform communication using intermittent windows that are opened at predetermined intervals according to the established synchronization. Have.

As described above, since communication is performed using the intermittent window, transmission / reception opportunities can be ensured regardless of the size of the data, and power consumption can be saved by setting the time other than the intermittent window to the sleep state.

(3) The

synchronous communication units

144 and 234 in the first relay unit 140 and the second relay unit 230 perform communication using an extended window that collectively transmits and receives information exceeding the capacity that can be communicated in one intermittent window. The

extended communication units

144b and 234b are included.

For this reason, it is possible to quickly transmit and receive large-capacity information through the extended window while securing an opportunity for transmission and reception through the intermittent window.

(4) The asynchronous communication unit 141 in the first relay unit 140 and the second relay unit 230 is used when the synchronization control unit 143 of the first relay unit 140 cannot receive the synchronization confirmation signal or the second relay unit 230 When the synchronization control unit 233 cannot receive the synchronization signal, communication in the asynchronous mode is performed.

For this reason, when synchronization cannot be established, necessary communication can be ensured as a state in which communication with each other is always possible.

(5) The

synchronization control units

143 and 233 include

correction units

143d and 233d that correct the start timing of the next intermittent window by adding or subtracting a predetermined offset value to the transmission time or reception time of the synchronization signal.

For this reason, the start timing can be accurately set by correcting the start timing in consideration of various factors such as a clock shift and the amount of information to be transmitted and received.

(6) The synchronization control unit 143 in the first relay unit 140 includes a synchronization setting unit 143a that sets the synchronization signal including the start timing of the intermittent window, the duration of the intermittent window, and the number of times the intermittent window is repeated. A synchronization establishment unit 143b that establishes synchronization with the gateway device 200 based on the setting content set by the unit 143a.

Therefore, synchronization can be established by notifying the smart meter 100 side to the gateway device 200 side of minimum information necessary for synchronization.

(7) The synchronization control unit 143 in the first relay unit 140, when the synchronization signal can be retransmitted in the same intermittent window as the intermittent window in which the synchronization confirmation signal for the synchronization signal could not be received, A retransmission control unit 143c that performs retransmission in the next and subsequent intermittent windows when retransmission is performed within the window and the intermittent window has passed.

For this reason, it is possible to transmit data at high speed and reliably by effectively using the opportunity of transmission.

(8) The gateway device 230 includes an accumulation unit 260 that accumulates the received information until a predetermined timing when the activation control unit 240 is activated in order for the second communication unit 220 to receive information.

For this reason, it is possible to store the received information and transmit the information at various timings according to the situation.

(9) The gateway device 230 transmits the information accumulated by the accumulation unit 260 at the next predetermined timing after the activation control unit 240 enters the activated state so that the second communication unit 220 receives the information. Until then, the activation setting unit 250 for setting activation conditions by the activation control unit 240 is provided so as to keep the activation state.

Therefore, only when there is accumulated information, it is possible to save power consumption by starting and transmitting after waiting for the next predetermined timing.

(10) The gateway device 230 is in the sleep state until the next predetermined timing comes after the activation control unit 240 is activated so that the second communication unit 220 receives the information, and the timing has arrived. In this case, the activation setting unit 250 sets activation conditions by the activation control unit 240 so that the information accumulated by the accumulation unit 260 is transmitted as the activation state.

Therefore, since the data received and stored in the storage unit is put into a sleep state until a predetermined timing comes next, power consumption can be further saved.

(11) The second relay unit 230 includes a channel setting unit 232 that sets, as a channel used for communication, one channel that periodically arrives among a plurality of channels.

Therefore, when the smart meter 100 uses the first communication unit 130 to transmit and receive data periodically using a plurality of channels, the second relay unit 230 also controls the window accordingly. By doing so, consistency between different networks can be achieved.

[Other Embodiments]
The present embodiment is not limited to the above aspect.
(1) The above embodiment is an application example of a smart meter for electric power. However, the information transmitted / received by the smart meter and the gateway device is not limited to the information exemplified above.

(2) As a network for transmitting and receiving information, any network that can be used at present or in the future can be used as long as the network can transmit and receive information. The above communication methods and protocols are examples, and it does not matter what communication method or protocol is used, whether wired or wireless.

(3) The above processing procedure is an example, and the processing can be omitted, added, or changed in order as long as it is not contrary to the technical idea of the present embodiment. In addition, the specific contents and values of the information used in the embodiment are free and are not limited to specific contents and numerical values.

(4) In the embodiment, in the determination of the magnitude of the value, the determination of mismatch, etc., the above is determined to include the value as follows, or the value is not included as greater, greater than, greater than, less than, or less than It is free to set whether to judge.

(5) Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope of the present invention and the gist thereof, and are also included in the invention described in the claims and the equivalent scope thereof.

100 smart meter 110 first connection unit 120 detection data acquisition unit 130 first communication unit 140 first relay unit 141 asynchronous communication unit 142 channel setting unit 143 synchronization control unit 143a synchronization setting unit 143b synchronization establishment unit 143c retransmission control unit 143d Correction unit 144 Synchronous communication unit 144a Intermittent communication unit 144b Extended communication unit 200 Gateway 210 Second connection unit 220 Second communication unit 230 Second relay unit 231 Asynchronous communication unit 232 Channel setting unit 233 Synchronization control unit 233a Synchronization setting Unit 233b synchronization establishment unit 233c retransmission control unit 233d correction unit 234 synchronous communication unit 234a intermittent communication unit 234b extended communication unit 240 activation control unit 250 activation setting unit 260 accumulation unit 400 WAN
500 HES
600 MDMS
700 HEMS
N1 First network N2 Second network N3 Relay network S Communication system

Claims

A first connection for connection to a power supply that constantly supplies power;
A detection data acquisition unit for acquiring detection data from the outside;
A first communication unit that transmits and receives detection data acquired by the detection data acquisition unit via a first network;
A first relay unit for connecting to a relay network;
A smart meter having
A second connection for connecting to a constant capacity power supply;
A second communication unit that communicates via a second network;
A second relay unit connected to the first relay unit via the relay network;
An activation control unit that controls whether the second communication unit and the second relay unit are in an activated state in which power consumption is high and communication is possible, or in a sleep state in which power consumption is low and communication is not performed;
A gateway device having
Have
The first relay unit and the second relay unit are
An asynchronous communication unit that performs communication in an asynchronous mode capable of continuous communication between the gateway device and the smart meter;
A synchronization control unit that establishes and maintains synchronization between the gateway device and the smart meter by transmitting and receiving a synchronization signal and a synchronization confirmation signal;
A synchronous communication unit that communicates in a synchronous mode in which the gateway device and the smart meter are in the activated state and communicate at a predetermined timing in accordance with established synchronization;
A communication system.
The communication system according to claim 1, wherein the synchronous communication unit in the first relay unit and the second relay unit includes an intermittent communication unit that performs communication by an intermittent window that opens at predetermined intervals according to established synchronization.
The synchronous communication unit in the first relay unit and the second relay unit includes an extended communication unit that performs communication using an extended window that collectively transmits and receives data exceeding a capacity that can be communicated in one intermittent window. 2. The communication system according to 2.
The asynchronous communication unit in the first relay unit and the second relay unit is configured such that the synchronization control unit of the first relay unit cannot receive a synchronization confirmation signal or the synchronization control unit of the second relay unit The communication system according to any one of claims 1 to 3, wherein communication in an asynchronous mode is performed when a synchronization signal cannot be received.
The said synchronous control part has a correction | amendment part which corrects the start timing of the next intermittent window by adding or subtracting a predetermined offset value to the transmission time or reception time of the said synchronous signal. Communication system.
A first connection for connection to a power supply that constantly supplies power;
A detection data acquisition unit for acquiring detection data from the outside;
A first communication unit that transmits and receives detection data acquired by the detection data acquisition unit via a first network;
A first relay unit for connecting to a relay network;
Have
The first relay unit is
An asynchronous communication unit that performs communication in an asynchronous mode capable of always communicating data with the gateway device via the relay network;
A synchronization control unit that establishes and maintains synchronization with the gateway device by transmitting and receiving a synchronization signal and a synchronization confirmation signal;
A synchronous communication unit that communicates with the gateway device in a synchronous mode that is in the activated state and communicates at a predetermined timing according to the established synchronization;
Having a smart meter.
The synchronous communication unit has an intermittent communication unit that performs communication by an intermittent window that opens at predetermined intervals according to established synchronization,
The synchronization control unit is configured to set the synchronization signal including the start timing of the intermittent window, the duration of the intermittent window, and the number of times the intermittent window is repeated,
A synchronization establishment unit that establishes synchronization with the gateway device based on the setting content set by the synchronization setting unit;
The smart meter according to claim 6.
If the synchronization signal can be retransmitted within the same intermittent window as the intermittent window in which the synchronization confirmation signal for the synchronization signal could not be received, the synchronization control unit retransmits the intermittent window and transmits the intermittent window. The smart meter according to claim 6 or 7, further comprising a retransmission control unit configured to perform retransmission in an intermittent window from the next time onward.
A second connection for connecting to a constant capacity power supply;
A second communication unit that communicates via a second network;
A second relay unit connected to the smart meter via the relay network;
An activation control unit that controls whether the second communication unit and the second relay unit are in an activated state in which power consumption is high and communication is possible, or in a sleep state in which power consumption is low and communication is not performed;
Have
The second relay unit is
An asynchronous communication unit that communicates in an asynchronous mode capable of always communicating with the smart meter via the relay network;
A synchronization control unit that establishes and maintains synchronization by transmitting and receiving a synchronization signal and a synchronization confirmation signal to and from the smart meter;
A synchronous communication unit that communicates with the smart meter in a synchronous mode that is in the activated state and communicates at a predetermined timing according to the established synchronization;
A gateway device.
10. The gateway apparatus according to claim 9, wherein the activation control unit includes an accumulation unit that accumulates information received until the predetermined timing when the second communication unit is activated to receive information.
The activation control unit continuously activates until the second predetermined communication timing is reached after the second communication unit receives the information until the next predetermined timing arrives and the accumulation unit transmits the accumulated information. The gateway device according to claim 10, further comprising an activation setting unit that sets an activation condition by the activation control unit.
The activation control unit enters the sleep state until the next predetermined timing comes after the second communication unit is activated to receive information, and the storage unit is activated when the timing arrives. The communication system according to claim 10, further comprising an activation setting unit configured to set an activation condition by the activation control unit so as to transmit the accumulated information.
The channel relay unit according to any one of claims 9 to 12, wherein the second relay unit includes a channel setting unit that sets, as a channel used for communication, one channel that periodically arrives among a plurality of channels. Gateway device.
A first connection for connecting to a power supply that constantly supplies power;
A detection data acquisition unit for acquiring detection data from the outside;
A first communication unit that transmits and receives data acquired by the detection data acquisition unit via a first network;
A first relay unit for connecting to a relay network;
On a computer with
Asynchronous communication processing for performing communication in an asynchronous mode capable of always communicating data with the gateway device via the relay network;
A synchronization control process for establishing and maintaining synchronization with the gateway device by transmitting and receiving a synchronization signal and a synchronization confirmation signal;
Synchronous communication processing for communicating with the gateway device in a synchronous mode that is in the activated state and communicates at a predetermined timing according to established synchronization;
Communication program that executes
A second connection for connecting to a constant capacity power supply;
A second communication unit that communicates via a second network;
A second relay unit connected to the smart meter via the relay network;
An activation control unit that controls whether the second communication unit and the second relay unit are in an activated state in which power consumption is high and communication is possible, or in a sleep state in which power consumption is low and communication is not performed;
On a computer with
An asynchronous communication unit that performs communication in an asynchronous mode capable of always communicating with the smart meter via the relay network;
A synchronization control unit that establishes and maintains synchronization by transmitting and receiving a synchronization signal and a synchronization confirmation signal to and from the smart meter;
A synchronous communication unit that communicates with the smart meter in a synchronous mode that is in the activated state and communicates at a predetermined timing according to the established synchronization;
A communication program.