JP2011109337A - Communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication system that allows a communication device which requires information about a radio unit for intermittent communication quickly determines whether the radio unit is active or not. <P>SOLUTION: A communication system 1 includes a communication device 10, a relay device 20 for communicating with the communication device 10, and a sensor 30 which performs radio intermittent communication with the relay device 20. The radio device 20 includes: a relay device storage part 210 which stores an identification ID for identifying the sensor 30 in association with hierarchy information representing a layer to which the sensor 30 identified by identification ID belongs under control of the relay device 20; and a relay device receiving part 220 which receives the information request signal for a specific sensor 30 from the communication device 10; and a relay device transmitting part 230 which transmits a response signal to an information request signal as well as the hierarchy information associated with the identification ID of the specific sensor 30 and stored in the relay device storage part 210 to the communication device 10 so long as the identification ID of the specific sensor 30 representing a recipient of the information request signal received by the relay device receiving part 220 is stored in the relay device storage part 210. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a communication system including a communication device, a relay device that communicates with the communication device, and a wireless device that performs wireless intermittent communication with the relay device.

  2. Description of the Related Art Conventionally, an information requesting device that collects information on home appliances that is located outside or within a network composed of various home appliances generally collects information on home appliances located on the network. ing.

  As an example of a method for collecting information on such household electrical appliances, after a portable terminal user leaves the home with a portable terminal, the representative of household electrical appliances (TV, DVD player, etc.) It is known that the proxy node collects information on other home appliances and transmits the device information to a mobile terminal located outside the home (see, for example, Patent Document 1).

  As another example, when the state of the home appliance changes, the home appliance transmits operation history data indicating the state change contents to the home gateway, and the home gateway holds the operation history data, It is known to transmit operation history data held at the time to an information server via the Internet (see, for example, Patent Document 2).

JP 2007-243756 A JP 2005-244753 A

  When collecting information on general home appliances as shown in Patent Documents 1 and 2, since there is little need for highly real-time communication, it is located in the network, and the information collecting device (portable terminal, Information on home appliances in the network can be stored in advance in a device (a proxy node, a home gateway, etc., hereinafter also referred to as a proxy device) that communicates with an information server or the like.

  However, when collecting information on devices that change information in a short time, such as information on sensors that detect some state (hereinafter also referred to as specific devices), it is necessary to perform highly real-time communication. The proxy device cannot store such specific device information in advance. Therefore, the proxy device needs to acquire information on the specific device when necessary.

  In addition, restrictions on communication between various home appliances and proxy devices disclosed in Patent Documents 1 and 2 are not particularly considered, but if the specific device is a power-saving wireless device, the specific device and the proxy device Intermittent communication may occur with

  FIG. 11 is a diagram illustrating a communication sequence when a conventional information collection device collects information on a wireless device that supports power saving via a proxy device. As shown in FIG. 11, after the information collecting apparatus transmits an information request signal to the proxy device (step S1001), the proxy device transmits an information request signal to the wireless device in order to acquire information that changes in a short time (step S1001). S1002). Upon receiving the information request signal, the wireless device returns information on the wireless device to the proxy device (step S1003), and the proxy device transmits the received information on the wireless device to the information collection device (step S1004). In this way, the information collecting apparatus can acquire information on the wireless device.

  However, the period of intermittent communication (intermittent period) between the proxy device and the wireless device shown in FIG. 11 is much longer than that of a wireless LAN or the like in order to reduce the power consumption of the wireless device (for example, It may be set to about ten or more seconds. When such intermittent communication with a long intermittent cycle is performed, it takes a long time to perform the processes of steps S1001 to S1004. During this time, the information collecting apparatus cannot grasp whether or not communication with the wireless device is possible. Therefore, in order to avoid unnecessary power consumption, it is desirable that the information collection device can grasp as quickly as possible that the radio is effectively present before acquiring the radio information.

  The present invention has been made in view of the above circumstances, and a communication device that requests information on a wireless device that performs intermittent communication can quickly grasp whether or not the wireless device is effectively present. It is an object to provide a simple communication system.

  The communication system of the present invention is a communication system including a communication device, a relay device that communicates with the communication device, and a radio that performs wireless intermittent communication with the relay device, and the relay device includes the wireless device. A relay device storage unit that associates and stores an identification ID for identifying a device and hierarchical information indicating a layer to which a radio identified by the identification ID belongs under the relay device, and a specification from the communication device A relay device receiving unit that receives an information request signal to the radio device, and an identification ID of the specific radio device that indicates a transmission destination of the information request signal received by the relay device receiving unit is stored in the relay device storage unit A relay device transmitting unit that transmits a predetermined signal indicating that the identification ID of the specific wireless device is stored in the relay device storage unit to the communication device.

  With this configuration, a communication device that requests information on a wireless device that performs intermittent communication can quickly determine whether or not the wireless device is effectively present when the relay device performs a proxy response of the wireless device. Is possible.

  The communication system of the present invention is a communication system including a communication device, a relay device that communicates with the communication device, and a radio that performs wireless intermittent communication with the relay device, and the relay device includes: A relay device storage unit that associates and stores an identification ID for identifying the wireless device and hierarchical information indicating a hierarchy to which the wireless device identified by the identification ID belongs under the relay device; and from the communication device A relay device receiving unit that receives an information request signal to the specific radio device, and an identification ID of the specific radio device indicating a transmission destination of the information request signal received by the relay device receiving unit is the relay device storage unit The response information for the information request signal and the hierarchical information stored in the relay device storage unit in association with the identification ID of the specific wireless device are transmitted to the communication device. That includes a relay device transmitting unit.

  With this configuration, a communication device that requests information on a wireless device that performs intermittent communication can quickly determine whether or not the wireless device is effectively present.

  In the communication system of the present invention, the communication device is transmitted by a communication device transmitter that transmits an information request signal to the specific radio device to the relay device, and the communication device transmitter from the relay device. A communication device receiver that receives the response signal and the hierarchy information for the received information request signal, and the identification from reception of the response signal from the relay device based on the hierarchy information received by the communication device receiver A communication device setting unit that sets a time-out period indicating a time limit until reception of information on the specific wireless device from the wireless device.

  With this configuration, it is possible to know whether a communication failure or a communication delay has occurred in the relay path between the communication device and the specific sensor by setting the timeout time according to the hierarchy information.

  In the communication system of the present invention, the communication device setting unit sets the timeout time longer as the hierarchy indicated by the hierarchy information is lower.

  With this configuration, when it is expected that the time until acquiring information of a specific wireless device will be long, the timeout time can be set long, and an appropriate timeout time can be set according to the hierarchy.

  In the communication system of the present invention, the relay device storage unit stores the identification ID, information on a relay route to the radio identified by the identification ID, and the hierarchy information in association with each other, and The relay device determines whether or not the relay device receiver has received information on the specific radio from the specific radio device within a predetermined time, and the relay device determination unit determines the specific When it is determined that the information of the wireless device is not received, the relay route for transmitting the information request signal to the specific wireless device is changed based on the relay route stored in the relay device storage unit A relay route changing unit that transmits a timeout extension instruction signal for extending the timeout time based on the change of the relay route by the relay route changing unit.

  With this configuration, even when the relay route is changed due to a communication failure or the like, the timeout time can be appropriately reset.

  In the communication system of the present invention, the relay device transmission unit transmits the hierarchy information stored in the storage unit in association with the relay route after the change by the relay route change unit together with the timeout extension instruction signal.

  With this configuration, it is possible to appropriately reset the time-out period corresponding to the hierarchy information by notifying the information requesting communication device of the hierarchy information corresponding to the changed relay route.

  In the communication system of the present invention, the communication device setting unit resets the timeout time based on the timeout extension instruction signal received by the communication device reception unit.

  With this configuration, even when the relay route is changed due to a communication failure or the like, the timeout time can be appropriately reset.

  According to the present invention, it is possible for a communication device that collects information on wireless devices to grasp whether or not a specific device is effective.

The block diagram which shows an example of the system configuration | structure of the communication system in the 1st Embodiment of this invention. The block diagram which shows an example of a structure of the relay apparatus in the 1st Embodiment of this invention The block diagram which shows an example of a structure of the communication apparatus in the 1st Embodiment of this invention. The time chart which shows an example of the intermittent communication performed between the relay apparatus and sensor in the 1st Embodiment of this invention FIG. 3 is a sequence diagram illustrating an example of communication between devices in the communication system according to the first embodiment of this invention. The flowchart which shows an example of operation | movement of the relay apparatus in the 1st Embodiment of this invention. The flowchart which shows an example of operation | movement of the communication apparatus in the 1st Embodiment of this invention. The block diagram which shows an example of the system configuration | structure of the communication system in the 2nd Embodiment of this invention. The figure which shows an example of the table which the relay apparatus memory | storage part in the 2nd Embodiment of this invention has. The sequence diagram which shows an example of the communication between each apparatus in the communication system of the 2nd Embodiment of this invention. The figure which shows the communication sequence at the time of the conventional information collection apparatus collecting the information of the radio | wireless machine corresponding to a power saving via a proxy apparatus

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a block diagram showing an example of a system configuration of a communication system according to the first embodiment of the present invention. The communication system 1 shown in FIG. 1 includes a monitoring device 11, a meter 12, a security control device 13, a relay device 20, and a sensor 30. Note that there may be a plurality of monitoring devices 11, meters 12, security control devices 13, and relay devices 20. The number of sensors 30 is not limited to the example shown in FIG.

  The monitoring device 11, the meter 12, and the security control device 13 can transmit an information request signal for requesting sensor information such as measurement information by the sensor 30. The information request signal is a signal for requesting sensor information such as battery information of the sensor 30, information on a measurement result by the sensor 30, and survival confirmation information indicating whether or not the sensor 30 can be operated effectively. Hereinafter, the monitoring device 11, the meter 12, and the security control device 13 that transmit information request signals are also referred to as communication devices 10.

  The monitoring device 11 is a device that monitors the meter 12, the security control device 13, the relay device 20, and the sensor 30, and is arranged, for example, in an information center managed by a gas company and an information center managed by a security management company. The monitoring device 11 has a wired or wireless communication function, and transmits an information request signal to the sensor 30 via the relay device 20. The information request signal transmitted by the monitoring device 11 may include various commands such as a meter reading command, a security management command for grasping a gas leak, and a remote shut-off command for the gas meter.

  The meter 12 is a gas meter, for example, and performs wired communication with the relay device 20. The meter 12 transmits an information request signal to the sensor 30 via the relay device 20.

  The security control device 13 is, for example, a control device having a security operation panel that performs various controls for crime prevention and disaster prevention, and performs wired communication with the relay device 20. Further, the security control device 13 transmits an information request signal to the sensor 30 via the relay device 20.

  The relay device 20 has a wired and wireless communication function, and relays communication between the communication device 10 (the monitoring device 11, the meter 12, or the security control device 13) and the sensor 30. Further, the relay device 20 manages one or a plurality of sensors 30 and performs intermittent communication wirelessly with the sensors 30.

  The sensor 30 is an example of a wireless device having a wireless communication function, and is, for example, a window opening / closing detection sensor, a gas leak sensor, a fire sensor, a fire alarm, or the like. Sensor 30 may be attached to household appliances, such as a refrigerator and an air conditioner, and may detect the state of the household appliances. The sensor 30 transmits sensor information to the communication device 10 in response to an information request signal from the communication device 10 (the monitoring device 11, the meter 12, or the security control device 13) or periodically. For example, the sensor 30 performs various measurements based on various commands such as a meter reading command and notifies the measurement result. Further, the sensor 30 may be a wireless device that communicates information other than the sensor information and that can change in a short time for which real-time property is required.

  Next, FIG. 2 is a block diagram illustrating an example of the configuration of the relay device 20. The relay device 20 illustrated in FIG. 2 includes a relay device storage unit 210, a relay device reception unit 220, a relay device transmission unit 230, and a relay device control unit 240.

  The relay device storage unit 210 includes at least an identification ID for identifying the sensor 30 and hierarchical information indicating a hierarchy to which the sensor 30 identified by the identification ID under the relay device 20 belongs (for example, transmission destination (destination)) In order to communicate with a specific sensor 30, the number of repeaters (number of hops) when passing through another sensor 30 functioning as a repeater other than the transmission destination is associated with Has a table to store.

  The relay device receiving unit 220 receives various signals and various information. For example, the relay device receiving unit 220 receives an information request signal for requesting information from a specific sensor 30 from the communication device 10.

  The relay device transmission unit 230 transmits various signals and various information. For example, when the identification ID of the specific sensor 30 indicating the transmission destination of the information request signal received by the relay device receiving unit 220 is stored in the relay device storage unit 210, the relay device transmission unit 230 stores this information request signal. And the hierarchical information stored in the relay device storage unit 210 in association with the identification ID of the specific sensor 30 are transmitted to the communication device 10 that transmitted the information request signal. For example, when the identification ID of the specific sensor 30 is stored in the relay device storage unit 210, the relay device transmission unit 230 stores the identification ID of the specific sensor 30 in the relay device storage unit 210. A predetermined signal may be transmitted.

  The relay device control unit 240 performs various controls in the relay device 20.

  Next, FIG. 3 is a block diagram illustrating an example of the configuration of the communication device 10. The communication device 10 illustrated in FIG. 3 includes a communication device transmission unit 110, a communication device reception unit 120, and a communication device control unit 130.

  The communication device transmission unit 110 transmits various signals and various information to the relay device 20. For example, the communication device transmission unit 110 transmits an information request signal for a specific sensor 30 that is a transmission destination to the relay device 20.

  The communication device receiving unit 120 receives various signals and various information from the relay device 20. For example, the communication device reception unit 120 receives a response signal and hierarchy information for the information request signal from the relay device 20.

  The communication device control unit 130 performs various controls in the communication device 10. For example, the communication device control unit 130 sets a timeout time based on the hierarchy information received by the communication device reception unit 120. Here, the time-out time is a time indicating a time limit from reception of a response signal from the relay device 20 to reception of information (sensor information) for an information request signal from a specific sensor 30.

Next, intermittent communication performed between the relay device 20 and the sensor 30 will be described.
FIG. 4 is a time chart illustrating an example of intermittent communication performed between the relay device 20 and the sensor 30.

  As shown in FIG. 4, the relay device 20 periodically transmits and receives signals to and from the sensor 30 at the intermittent cycle T1. Further, the relay device 20 periodically repeats the transmission operation and the reception operation alternately. Similarly, the sensor 30 periodically transmits and receives signals to and from the relay device 20 at the intermittent period T1. Further, the sensor 30 periodically repeats the transmission operation and the reception operation alternately. The timings at which the relay device 20 and the sensor 30 perform the transmission operation and the reception operation may be different. In addition, during a transmission operation and a reception operation, a predetermined signal, an information request signal, or a signal to be transmitted / received such as sensor information is transmitted / received. The intermittent period T1 is, for example, 3 sec to 10 sec, and preferably 6 sec to 8 sec in consideration of the balance between power saving and response time.

  The own device (relay device 20 or sensor 30) starts the reception operation when there is information to be transmitted to the counterpart device (sensor 30 or relay device 20). In the reception operation of the own device, when the transmission timing of the counterpart device is recognized by receiving a predetermined signal from the counterpart device, the own device shifts to the transmission operation in accordance with the subsequent reception operation of the counterpart device. Send information to be sent.

  For example, when the sensor 30 transmits sensor information to the relay device 20, the repetition of the periodic transmission operation and reception operation is temporarily suspended and the reception operation is started (time t1 in FIG. 4). When the transmission timing of the relay device 20 is recognized during the reception operation of the sensor 30 (time t2 in FIG. 4), the sensor 30 shifts to the transmission operation in accordance with the subsequent reception operation of the relay device 20 (time t3 in FIG. 4). The sensor 30 transmits the sensor information to the relay device 20. Although not shown in FIG. 4, the same operation as that of the sensor 30 is performed when the relay device 20 transmits an information request signal to the sensor 30.

Next, communication between each device in the communication system 1 will be described.
FIG. 5 is a sequence diagram illustrating an example of communication between devices in the communication system 1.

  First, the communication device 10 transmits an information request signal including the identification ID of the specific sensor 30 to the relay device 20 in order to transmit the information request signal to the specific sensor 30 that is the transmission destination (step S101). When the relay device 20 receives the information request signal from the communication device 10, the relay device 20 refers to the relay device storage unit 210, and responds to the hierarchical information associated with the identification ID of the specific sensor 30 and the information request signal (ACK signal). Is transmitted to the communication device 10 (step S102). The relay device 20 may transmit the hierarchy information included in the response signal, or may transmit the hierarchy information and the response signal separately.

The communication device 10 sets a timeout time based on the hierarchy information from the relay device 20 (step S103). The timeout time is determined by the communication device control unit 130, for example, according to (Equation 1).
Tout = (2 × T1 × hop number) + α
α = (2 × T1 × hop number) × 0.2 to 0.3
Note that Tout: timeout time, T1 = intermittent cycle, and α: margin for setting timeout time. For example,
When T1 = 5 sec and the number of hops = 1, Tout = 12 sec
When T1 = 5 sec and the number of hops = 2, Tout = 24 sec
It is.
As described above, the communication device control unit 130 sets the timeout time longer as the hierarchy indicated by the hierarchy information is lower (the higher the Hop number, that is, the greater the number of relay stations).

  Further, when receiving the information request signal in step S101, the relay device 20 transmits the information request signal to the specific sensor 30 (step S104). When the specific sensor 30 receives the information request signal from the communication device 10, information (sensor information) for the information request signal is transmitted to the communication device 10 via the relay device 20 (steps S105 and S106).

  Note that the communication device 10 may perform broadcast communication using all the sensors 30 as transmission destinations instead of designating a specific sensor 30 as the transmission destination of the information request signal.

  In addition, the relay device 20 does not directly transmit an information request signal to the specific sensor 30, but stores information on the relay route to the specific sensor 30 in the table of the relay device storage unit 210, and Based on the information, an information request signal may be transmitted to a specific sensor 30 via another sensor 30 other than the transmission destination.

Next, the operation of the relay device 20 will be described.
FIG. 6 is a flowchart illustrating an example of the operation of the relay device 20.

  First, the relay device receiving unit 220 receives an information request signal from the communication device 10 (step S201). Subsequently, the relay device control unit 240 refers to the table included in the relay device storage unit 210 (step S202), and determines whether or not the identification ID of the specific sensor 30 to which the information request signal is to be transmitted is stored. (Step S203). When the identification ID of the specific sensor 30 is not stored in the relay device storage unit 210, the relay device transmission unit 230 transmits sensor non-existence information indicating that the specific sensor 30 does not exist to the communication device 10 (step) S204). Note that the response to the communication device 10 in response to the information request signal may be abandoned without transmitting the sensor absence information by the relay device transmission unit 230.

  On the other hand, when the identification ID of the specific sensor 30 is stored in the relay device storage unit 210, the relay device transmission unit 230 transmits a response signal and hierarchy information to the information request signal from the communication device 10 to the communication device 10. (Step S205). The relay device transmission unit 230 transmits the information request signal from the communication device 10 to the specific sensor 30 identified by the identification ID (step S206). Subsequently, the relay device receiving unit 220 receives sensor information from the specific sensor 30 (step S207). Subsequently, the relay device transmission unit 230 transmits the sensor information received by the relay device reception unit 220 to the communication device 10 (step S208).

Next, the operation of the communication device 10 will be described.
FIG. 7 is a flowchart illustrating an example of the operation of the communication device 10.

  First, the communication device transmission unit 110 transmits an information request signal to the relay device 20 that is a transmission destination (step S301). Subsequently, the communication device control unit 130 determines whether the communication device reception unit 120 has received a response signal and hierarchy information for the information request signal from the relay device 20 (step S302). The communication device control unit 130 repeats the process of step S302 until the communication device reception unit 120 receives the response signal and the hierarchy information.

  When it is determined that the response signal and the hierarchy information are received, the communication device control unit 130 sets a timeout time based on the received hierarchy information (step S303). Subsequently, the communication device control unit 130 determines whether or not the sensor information from the sensor 30 is received by the communication device reception unit 120 (step S304). The communication device control unit 130 repeats the process of step S304 until the communication device reception unit 120 receives the sensor information.

  When the sensor information is received by the communication device reception unit 120, the communication device control unit 130 determines whether or not the reception time of the sensor information is within the timeout time (step S305). If the reception time of the sensor information is within the timeout time, the communication device control unit 130 performs normal processing on the received sensor information (step S306). On the other hand, if the reception time of the sensor information is outside the timeout time, the communication device control unit 130 ignores the received sensor information as not being normally received and discards it (step S307). .

  According to the communication system 1 in the first embodiment of the present invention, the communication device 10 makes a proxy response instead of the specific sensor 30 before the communication device 10 acquires sensor information that should be acquired. Thus, it can be known in advance whether or not the specific sensor 30 exists effectively. If it becomes clear that the specific sensor 30 does not exist effectively, it is not necessary to repeatedly transmit the information request signal within the timeout time, so that power saving and communication traffic can be reduced. In addition, by setting the timeout time, it is possible to know whether a communication failure or a communication delay has occurred in the relay path between the communication device 10 and the specific sensor 30.

(Second Embodiment)
FIG. 8 is a diagram illustrating an example of a system configuration of a communication system according to the second embodiment of the present invention. A communication system 1B illustrated in FIG. 8 includes a communication device 10, a relay device 20, and a plurality of sensors 30 (30A, 30B, 30C, 30D,...). A plurality of communication devices 10 and relay devices 20 may be provided. The number of sensors 30 is not limited to the example shown in FIG. In FIG. 8, the communication device 10 is shown, but the relationship between the monitoring device 11, the meter 12, the security control device 13, the relay device 20, and the sensor 30 is the same as the example shown in FIG. That is, the monitoring device 11 and the relay device 20 perform wired communication or wireless communication, the meter 12 and the relay device 20 perform wired communication, and the security control device 13 and the relay device 20 perform wired communication. In the communication system 1B shown in FIG. 8, the same components as those in the communication system 1 shown in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted or simplified.

  The relay device storage unit 210 includes at least an identification ID of the sensor 30, information on the relay route to the sensor 30 identified by the identification ID, and hierarchical information (such as the number of hops) when the relay route is used. It has a table to store in association.

  FIG. 9 is a diagram illustrating an example of a table included in the relay device storage unit 210. In the example illustrated in FIG. 9, as information regarding the sensor 30 </ b> C identified by the identification ID “1”, the relay device 20, the sensor 30 </ b> B, and the sensor 30 </ b> C are relayed from the communication device 10 to the sensor 30 </ b> C that is the destination sensor. And relay information indicating that the number of hops in the case of this route is 2 is stored in the relay device storage unit 210. Further, as information regarding the sensor 30D identified by the identification ID “2”, relay route information indicating that the relay device 20, the sensor 30A, and the sensor 30D are relayed in order of the communication device 10 to the sensor 30D that is the destination sensor. And the hierarchy information indicating that the number of hops in the case of this route is 2 is stored in the relay device storage unit 210. Further, as information on another route of the sensor 30D, relay route information indicating that the relay device 20, the sensor 30B, the sensor 30C, and the sensor 30D are relayed in this order from the communication device 10 to the sensor 30D that is the transmission destination sensor. Hierarchy information indicating that the number of hops in the case of a route is 3 is stored in the relay device storage unit 210.

Next, communication between each device in the communication system 1B will be described.
FIG. 10 is a sequence diagram illustrating an example of communication between devices in the communication system 1B. Here, the destination sensor is the sensor 30D, and as shown in FIG. 8, communication between the relay device 20 and the sensor A is not possible, and the relay path from the relay device 20 to the sensor 30D is indicated by the sensor 30A. It is assumed that the route is changed from the route through to the route through the sensor 30B and the sensor 30C.

  First, the communication device 10 transmits an information request signal including the identification ID of the sensor 30D to the relay device 20 so that the communication device transmission unit 110 transmits the information request signal to the sensor 30D that is the specific sensor 30 that is the transmission destination. Transmit (step S401). When the relay device 20 receives the information request signal from the communication device 10 through the relay device receiving unit 220, the relay device control unit 240 refers to the table of the relay device storage unit 210, and the relay device transmission unit 230 uses the sensor 30D. The hierarchy information (hop number “2”) associated with the identification ID “2” and the response signal (ACK signal) to the information request signal are transmitted to the communication device 10 (step S402). At this time, the hierarchy information may be included in the response signal and transmitted, or the hierarchy information and the response signal may be transmitted separately.

  The communication device 10 sets a timeout time based on the hierarchy information from the relay device 20 by the communication device control unit 130 (step S403). Also, when the relay device 20 receives the information request signal from the relay device receiving unit 220 in step S401, the relay device transmitting unit 230 causes the relay device transmitting unit 230 to store a predetermined relay path (here, via the sensor 30A) stored in the relay device storage unit 210. Route), the information request signal is transmitted to the sensor 30D (step S404). The priority for selecting the relay route in the relay device 20 may be determined in advance, the relay route may be determined based on the priority, and the information request signal may be transmitted through the relay route.

  The relay device 20 determines whether the relay device control unit 240 has received the sensor information from the sensor 30D by the relay device reception unit 220 within a predetermined time from the transmission of the information request signal (step S405). Then, when the sensor information from the sensor 30D is not received, the relay device control unit 240 changes the relay path when transmitting the information request signal to the sensor 30D. Here, the relay route is changed to a route through the sensor 30B and the sensor 30C. When the relay route is changed, the relay device control unit 240 may arbitrarily select a relay route other than the relay route that transmitted the information request signal in step S404, or may select another relay route based on the priority. A route may be selected. Note that the predetermined time is determined based on the hierarchy information as in step S103, and is proportional to the number of Hops, for example.

  The relay device 20 retransmits the information request signal to the sensor 30D through the changed relay route by the relay device transmission unit 230 (step S406).

  When the relay route is changed by the relay device control unit 240, the relay device 20 sends a timeout extension instruction signal for extending the already set timeout time to the communication device 10 by the relay device transmission unit 230. Transmit (step S407). In addition to the transmission of the timeout extension signal, the relay device transmission unit 230 may transmit the hierarchy information (hop number “3”) stored in the relay device storage unit 210 in association with the changed relay route.

  When the communication device receiving unit 120 receives the timeout extension instruction signal from the relay device 20, the communication device 10 resets the timeout time by the communication device control unit 130 (step S408).

For example, the communication device control unit 130 resets the timeout time (RTout) (timeout time for the route through the sensor 30B and sensor 30C) to the already set timeout time Tout (timeout for the route through the sensor 30A). Time) (N times, for example, 1.5 times). That means
RTout = Tout × N
It is good.

  Further, when the communication device receiving unit 120 receives the hierarchy information together with the timeout extension signal from the relay device 20, the communication device control unit 130 sets the layer corresponding to the changed relay route in the same manner as the setting of the timeout time Tout. The timeout time RTout may be reset based on the information.

  According to the communication system 1B in the second embodiment of the present invention as described above, for example, the relay route is changed and the hierarchy information is changed, and the state of the changed relay route cannot be accurately grasped at the initial timeout time. Even if it is expected, whether or not a communication failure or a communication delay has occurred in the relay path after the change between the communication device 10 and the specific sensor 30 by resetting the timeout time. Know exactly.

  In the present embodiment, the relay device storage unit 210 of the relay device 20 exemplifies that the relay route information from the relay device 20 to the specific sensor 30 that is the transmission destination is centrally managed. Each apparatus 30 may select a relay route autonomously by having information on the relay route to each specific sensor 30.

  INDUSTRIAL APPLICABILITY The present invention is useful for a communication system or the like in which a communication device that requests information on a wireless device that performs intermittent communication can quickly grasp whether or not the wireless device is effectively present.

1, 1B communication system 10 communication device 11 monitoring device 12 meter 13 security control device 20 relay device 30, 30A-30D sensor 110 communication device transmission unit 120 communication device reception unit 130 communication device control unit 210 relay device storage unit 220 relay device reception 230 Relay device transmitter 240 Relay device controller

Claims (7)

A communication system comprising: a communication device; a relay device that communicates with the communication device; and a radio that performs wireless intermittent communication with the relay device,
The relay device is
A relay device storage unit that associates and stores an identification ID for identifying the wireless device and hierarchical information indicating a hierarchy to which the wireless device identified by the identification ID belongs under the relay device;
A relay device receiving unit that receives an information request signal from the communication device to a specific wireless device;
When the identification ID of the specific wireless device indicating the transmission destination of the information request signal received by the relay device receiving unit is stored in the relay device storage unit, for the communication device, the specific wireless device A relay device transmission unit that transmits a predetermined signal indicating that the identification ID of is stored in the relay device storage unit;
A communication system comprising: A communication system comprising: a communication device; a relay device that communicates with the communication device; and a radio that performs wireless intermittent communication with the relay device,
The relay device is
A relay device storage unit that associates and stores an identification ID for identifying the wireless device and hierarchical information indicating a hierarchy to which the wireless device identified by the identification ID belongs under the relay device;
A relay device receiving unit that receives an information request signal from the communication device to a specific wireless device;
When the identification ID of the specific wireless device indicating the transmission destination of the information request signal received by the relay device receiving unit is stored in the relay device storage unit, a response signal to the information request signal and the relay device storage A relay device transmitting unit that transmits the hierarchical information stored in association with the identification ID of the specific wireless device to the communication device;
A communication system comprising: A communication system according to claim 2,
The communication device
A communication device transmitter for transmitting an information request signal to the specific radio device to the relay device;
A communication device receiving unit that receives the response signal and the hierarchy information with respect to the information request signal transmitted by the communication device transmitting unit from the relay device;
Based on the hierarchy information received by the communication device receiver, a time-out time indicating a time limit from reception of the response signal from the relay device to reception of the information on the specific radio from the specific radio A communication device setting unit for setting
A communication system comprising: A communication system according to claim 3,
The communication device setting unit sets the timeout time longer as the hierarchy indicated by the hierarchy information is lower. The communication system according to any one of claims 2 to 4,
The relay device storage unit stores the identification ID, information on a relay route to a radio identified by the identification ID, and the hierarchy information in association with each other,
The relay device is
A relay device determination unit that determines whether or not the information on the specific wireless device is received from the specific wireless device by the relay device reception unit within a predetermined time;
When the relay device determination unit determines that the information on the specific wireless device has not been received, the information request signal is sent to the specific wireless device based on the relay route stored in the relay device storage unit. A relay route changing unit for changing the relay route when transmitting,
With
The relay device transmitting unit transmits a timeout extension instruction signal for extending the timeout time to the communication device based on the change of the relay route by the relay route changing unit. The communication system according to claim 5, wherein
The relay device transmission unit transmits the hierarchy information stored in the storage unit in association with the relay route changed by the relay route change unit together with the timeout extension instruction signal. The communication system according to claim 5 or 6,
The communication device setting unit resets the timeout time based on the timeout extension instruction signal received by the communication device reception unit.

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