JP5041871B2 - Host computer and wireless network system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce power consumption of each node by allowing multiplexed information for use in communication of a wake-up signal to be assigned and shared with less power consumption and resources in a wireless communication system where a plurality of nodes perform asynchronous communication. <P>SOLUTION: Normally, a reception mode is operated in a sleep mode in which a data reception function (S120) is disabled. A transmission node transmits the wake-up signal for enabling the data reception function, to a data transmission destination node. At this time, the transmission mode calculates multiplexed information of the data transmission destination node on the basis of a network address of the data transmission destination node (S210), and transmits the wake-up signal on the basis of the calculated multiplexed information (S220). Only when receiving the wake-up signal corresponding to multiplexed information of the reception node itself, the reception mode is switched to an active mode in which the data reception function (S140) is enabled. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

The present invention is, for example, relates to sulfo strike computer and a wireless network system put to a network sensor terminal configuration.

  A system in which battery-powered sensor terminals are arranged at multiple points, the terminals are interconnected by a wireless network, and abnormality detection or environmental monitoring is performed at each point is called a sensor network system. In such a sensor network system, there is a ZigBee standard as a wireless communication standard for interconnecting sensor terminals.

In this ZigBee standard, there is a provision regarding multi-hopping communication so that the system can be laid out over a wide range, and even between terminals arranged at a distance where radio does not reach directly, a relay terminal arranged between them transmits packets. A system that allows communication by relaying is adopted.
The sensor terminal of such a system is called End Device in the ZigBee standard, and only activates the communication function when there is a communication request when an abnormality occurs, and stops the communication function otherwise. In this way, long-time operation by battery drive is realized.

  On the other hand, the relay terminal is called a router in the ZigBee standard. The Router is required to always enable the wireless communication function in order to relay a communication request from End Device that can occur asynchronously. Therefore, since the router consumes a lot of power, it is necessary not to use a battery as a power source but to supply power from the outside with a commercial power source or the like.

  Further, even in an end device (sensor terminal), in a system that needs to receive radio packets asynchronously, it is necessary to always enable the radio communication function. For example, in an anomaly detection system in which sensors for detecting anomalies at various points are arranged, if an anomaly is notified from a specific sensor, the details of the anomaly status that has occurred can be obtained if information from other sensors can be read. It becomes possible to know more in detail. Such communication is communication that occurs completely asynchronously for an end device that has not detected an abnormality. In order to enable such asynchronous communication, End Device needs to always enable the wireless communication function.

For example, the wireless LAN terminal of Patent Document 1 (hereinafter referred to as a wireless terminal or a terminal) shows a low power technique for a wireless terminal, but the low power effect can be obtained by communicating in synchronization with an event. Only on the terminal side. Moreover, power-on and communication start are determined only by the intention of the wireless terminal, and the activation of the wireless terminal from the server side is not mentioned, and the activation of the wireless terminal from the server side cannot be configured. Furthermore, the server side, that is, the side that accepts communication asynchronously needs to always have the communication function enabled. This is the same as the relationship between the sensor terminal and the relay terminal and “End Device not detecting an abnormality” shown in the example of the abnormality detection system. That is, the server side that accepts communication asynchronously cannot operate for a long time when the battery is used as a power source.
However, the wireless sensor network may be installed in a place where infrastructure facilities are not prepared, such as outdoors. In such a case, if the relay terminal and the terminal that accepts communication can achieve power saving and power can be supplied by a battery, there is no restriction on the installation location for the relay terminal and the terminal that accepts communication, In addition, the system can be constructed at low cost.
JP 2004-153359 A

The conventional wireless sensor network is configured as described above, and it is not possible to freely specify on / off of the battery of the terminal from the server side, and if the asynchronous communication from the server is allowed, sufficient power saving in the terminal can be achieved. There is a problem that it cannot be planned.
In addition, in the conventional system, there is a problem in that detailed control that power is turned on only from the time when communication is necessary until the end of communication, including the relay terminal, cannot be performed, and power saving is not sufficient.

Therefore, a method including wireless means for causing the data transmitting terminal to wake up the data receiving terminal using a wake-up signal at the start of data communication can be considered separately from the wireless data communication means.
The wireless terminal on the receiving side provided with the wake-up means is normally set in a low power consumption SLEEP (sleep) mode in which the data communication function is stopped, and when a wake-up signal is detected, that is, when a data communication request is detected. Only wake up to enable data communication function. As a result, it is possible to reduce the power consumption of the wireless terminal.

  In the wake-up signal detection process, intermittent radio wave intensity measurement is performed, and a wake-up signal is detected based on the measured radio wave intensity without performing address check or the like. For this reason, there is a merit that the power consumption by the wake-up means can be extremely reduced in both the data transmission side radio terminal and the data reception side radio terminal.

However, on the other hand, the wake-up means has a demerit that a terminal to wake up cannot be specified. The fact that the terminal to wake up cannot be specified means that all terminals arranged in a range where the wake-up signal transmitted by the data transmitting terminal can be detected will be woken up once, which is useless for terminals not related to data communication. Power consumption occurs.
Furthermore, since the power consumed when a terminal unrelated to the data communication is woken up is consumed regardless of the operation planned by the system, it is difficult to predict the battery life of each terminal. It leads to things.

As a technique to alleviate such problems, frequency channels and time slots are allocated to individual devices, and a wakeup signal is output to the frequency channels and time slots allocated to the receiving terminal from which the data transmitting terminal wants to receive data. It is conceivable to apply the multiple access method as described above.
Therefore, when the multiple access method is used, as a mechanism for the data transmitting terminal to know the multiplexed information (frequency channel, time slot) assigned to the receiving terminal before transmitting data, the multiplexed information is reduced in power consumption, A system that can allocate and share resources with few resources is important.

In a system in which the multiplexing information is limited and unique multiplexing information cannot be assigned to all terminals, the wake-up signal is detected by a plurality of terminals assigned the same multiplexing information. The occurrence of “interference” may cause a wake-up of a terminal not related to data communication.
Therefore, it is important to have a mechanism capable of assigning to reduce the interference of the wakeup signal and reassigning the multiplexed information in accordance with the interference state of the wakeup signal that changes every moment.

The present invention is an invention made to solve the above-mentioned problems, and wireless communication that wakes up a communication partner using multiplexed wake-up signals in order to reduce power consumption of a wireless communication system that performs asynchronous communication It is an object of the present invention to provide a device that can allocate and share multiplexed information with less power consumption and less resources.
It is another object of the present invention to provide a means for reallocating and sharing the multiplexed information according to position information and communication environment.

  The wireless communication apparatus according to the present invention uses a central processing unit (CPU) to transmit wireless communication multiplexing information used for communication of a wake-up signal indicating the start of data communication from another apparatus to the own apparatus based on the network address of the own apparatus. ), A wakeup signal detection unit that detects a wakeup signal for its own device using a communication device based on the multiplexing information obtained by the multiplexing information calculation unit, and the wakeup signal detection A mode control unit that uses a CPU to switch the operation mode of its own device from a sleep mode that pauses the data communication function to an active mode that activates the data communication function when the unit detects a wake-up signal, and the mode control Switched to active mode And a data receiving unit that receives communication data transmitted from another device later using a communication device.

According to the present invention, since the multiplexing information calculation unit obtains multiplexing information used for communication of the wakeup signal based on the network address of its own device, for example, it is wasted by switching to the active mode by the wakeup signal for another device. It is possible to prevent power consumption.
In addition, for example, it is possible to eliminate the need for communication in order to notify multiplexing information between wireless communication devices.
Also, for example, it is possible to eliminate the need to store and manage multiplexing information separately from the network address for other devices.

Embodiment 1 FIG.
FIG. 1 is a diagram showing an example of a communication system 900 having a network address configuration in the first embodiment.
The communication system 900 of FIG. 1 (an example of a wireless network system or a communication network) has a network address configuration (hereinafter referred to as an address tree) having a tree structure with a node 1 (network address: 0x0000) called a network coordinator as a vertex. ). Hereinafter, a node refers to a sensor terminal, a relay terminal, or a server terminal that transmits and receives data wirelessly.

In a communication system 900 that forms a tree structure as shown in FIG. 1, when a node enters the network, it searches for a node that can be a parent node from nodes located within its own communication range, and becomes a child node of that node. Formed with. At this time, the network address is assigned by the parent node.
The parent node limits the number of child nodes that can be assigned a network address to Cm. It is assumed that Cm is defined as a network common parameter.

The network address is composed of, for example, 16 bits, and the upper 4 bits (0 to F in hexadecimal) represent the distance (depth: Depth) from the network coordinator in the tree, and the lower 12 bits (16 (000 to FFF in decimal) indicates an offset address at the depth.
For example, in FIG. 1, when the “offset address” of a node 4 that is a child node of the network coordinator (node 1) and whose “depth” is “1” is “0x002”, The network address is “0x1002”.

  Further, the parent node gives an offset address in the following range to the child node based on its own offset address.

Ap (offset) x Cm
≦ Ac (offset) <(Ap (offset) +1) × Cm (Formula 1)
The symbols in the above formula mean the following.
Ap (offset): parent node offset address Ac (offset): child node offset address Cm: maximum number of child nodes the parent node can have

For example, when the maximum child node number Cm to which one parent node is connected is “3”, the offset address of the child node of the network coordinator (node 1) having the offset address “0x000” is “0x000” to “0”. 0x002 ".
Further, since the depth (Depth) of the child node of the network coordinator is “1”, the network addresses of the nodes 2, 3 and 4 which are child nodes of the network coordinator (node 1) in FIG. Are “0x1000”, “0x1001”, and “0x1002”, respectively.

  A network formed by all child nodes belonging to the same parent node is defined as one subnetwork. For example, in FIG. 1, node 5, node 6, and node 7 that are child nodes of node 2 constitute one subnetwork.

In addition, a node number in the subnetwork unique in the subnetwork is assigned to each node constituting the subnetwork.
For example, the subnetwork number to which an arbitrary node A belongs and the node number within the subnetwork can be calculated by the following formula 2, formula 3, formula 4, and formula 5 based on the network address of the node A. is there.

For example, in FIG. 1, since the “depth D (node 1)” is “0”, the network coordinator (node 1) has “subnetwork number Sid (node 1)” set to “0” according to Equation 2, According to Expression 3, “node number Nsid (node 1)” becomes “0”.
Further, for example, in FIG. 1, since “depth D (node 2)” is “1” in node 2, “subnetwork number Sid (node 2)” becomes “0 (= 0 + 0)” according to Equation 4. According to Expression 5, “node number Nsid (node 2)” becomes “1 (= 0 + 1)”.
Further, for example, in FIG. 1, since the “depth D (node 9)” is “2”, the node 9 has “subnetwork number Sid (node 9)” of “2 (= 3 ⁰ +1)” according to Expression 4. From Equation 5, “node number Nsid (node 9)” becomes “2 (= 1 + 1)”.
Further, for example, in FIG. 1, since the “depth D (node 14)” is “3” in the node 14, the “subnetwork number Sid (node 14)” is “4 (= (3 ¹ +3 ⁰ ) according to Equation 4. ) +0 ”, and“ node number Nsid (node 14) ”becomes“ 1 (= 0 + 1) ”according to Expression 5.

FIG. 2 is a table showing the network address, subnetwork number, and node number of each node in the first embodiment.
FIG. 2 shows the network address, subnetwork number, and node number assigned to each node shown in FIG. 1 according to the above description.

  Next, communication between nodes in Embodiment 1 performed based on the network address described above will be described.

  First, configurations of data reception node 100 and data transmission node 200 in communication system 900 of Embodiment 1 will be described based on FIGS. 3 and 4. Each node has both the configuration shown in FIG. 3 and the configuration shown in FIG. 4 when performing data transmission and data reception.

FIG. 3 is a functional configuration diagram of the data receiving node 100 according to the first embodiment.
In FIG. 3, the data reception node 100 (an example of a wireless communication apparatus) includes a mode control block 110, a wakeup signal detection multiplexing information calculation block 120, a wakeup signal detection block 130, a data reception block 140, and a reception node storage block 190. .
The mode control block 110 (an example of a mode control unit) controls the operation mode of the data reception node 100 using a CPU (Central Processing Unit), and normally stops the data reception block 140 and wakes up signal detection block. A low-power SLEEP (sleep) mode in which 130 is enabled (valid and operable) is set. Further, when the wakeup signal detection block 130 detects the wakeup signal, the mode control block 110 switches the operation mode to the ACTIVE (active) mode in which data communication can be performed. In the ACTIVE mode, the data reception block 140 is enabled and the wakeup signal detection block 130 is disabled (invalid, inoperable state). Further, the mode control block 110 switches the operation mode to the SLEEP mode when the data reception block 140 finishes data reception or when a predetermined time has elapsed after switching to the ACTIVE mode.
The wake-up signal detection block 130 (an example of a wake-up signal detection unit) performs a wake-up signal detection process based on the multiplexed information (frequency channel, time slot) calculated by the wake-up signal detection multiplexed information calculation block 120 in the SLEEP mode. Is performed using a communication device and a CPU.
The wakeup signal detection multiplex information calculation block 120 (an example of the multiplex information calculation unit) uses the CPU to multiplex information in the wireless communication of the wakeup signal transmitted to the own node based on the network address of the own node. To calculate.
The data reception block 140 (an example of a data reception unit) receives data transmitted by the data transmission node 200 in the ACTIVE mode.
The receiving node storage block 190 corresponds to the data received by the data receiving block 140, the network address of the own node, the multiplexing information calculated by the wakeup signal detection multiplexing information calculation block 120, and each frequency channel used as multiplexing information. Frequency information, reception timing information corresponding to time slots used as multiplexing information, and the like are stored.

FIG. 4 is a functional configuration diagram of the data transmission node 200 according to the first embodiment.
4, the data transmission node 200 (an example of a wireless communication apparatus) includes a wakeup signal output multiplexing information calculation block 210, a wakeup signal output block 220, a data transmission block 230, and a transmission node storage block 290.
The wakeup signal output multiplexing information calculation block 210 (an example of a multiplexing information calculation unit) uses the CPU based on the multiplexing information of the destination node (data receiving node 100) as the data transmission destination based on the network address of the destination node. To calculate.
The wakeup signal output block 220 (an example of a wakeup signal transmission unit) transmits a wakeup signal using a communication device based on the multiplexing information calculated by the wakeup signal output multiplexing information calculation block 210. As a result, the data receiving node 100 that has detected the wake-up signal enters the ACTIVE mode in which the receiving function is enabled, and data transmission from the data transmitting node 200 to the data receiving node 100 becomes possible.
The data transmission block 230 (an example of a data transmission unit) transmits data addressed to the data reception node 100 using a communication device after the wakeup signal output block 220 transmits a wakeup signal to place the data reception node 100 in the ACTIVE mode. Send.
The transmission node storage block 290 includes the data transmitted by the data transmission block 230, the network address of the own node, the network address of the data reception node 100 (for example, the parent node) that is the data transmission destination, and wakeup signal output multiplexing information. The multiplexing information calculated by the calculation block 210, the frequency information corresponding to each frequency channel used as multiplexing information, the transmission timing information corresponding to the time slot used as multiplexing information, and the like are stored.

FIG. 5 is a flowchart illustrating the wireless communication method according to the first embodiment.
A wireless communication method between data transmission node 200 and data reception node 100 in the first embodiment will be described below with reference to FIG.
Each block of the data transmission node 200 and the data reception node 100 executes the following processing using hardware such as a CPU and a communication device.

<S110: Reception multiplexing information calculation process>
First, in the data receiving node 100, the wake-up signal detection multiplexing information calculation block 120 calculates the multiplexing information of the own node based on the network address of the own node.
At this time, the wake-up signal detection multiplexing information calculation block 120 acquires the network address of the own node from the reception node storage block 190. Then, the wakeup signal detection multiplexing information calculation block 120 calculates multiplexing information of the own node based on the subnetwork number of the own node and the node number of the own node specified as described above from the acquired network address. The multiplexing information of the own node indicates the frequency channel and time slot used for transmitting the wakeup signal to the own node.
Details of the multiplexing information will be described later.

<S120: SLEEP mode switching process>
In the data receiving node 100, the mode control block 110 sets the operation mode of the data receiving node 100 to the SLEEP mode.
At this time, the mode control block 110 enables the wakeup signal detection block 130 and disables the data reception block 140.

<S210: Transmission Multiplexing Information Calculation Process>
When transmission data is generated in the data transmission node 200, the wakeup signal output multiplexing information calculation block 210 calculates multiplexing information of the data transmission destination node based on the network address of the data transmission destination node.
Here, it is assumed that transmission data is generated, for example, when a measurement value of a sensor (not shown) provided in the data transmission node 200 indicates an abnormal value and it is necessary to notify the server terminal of the detection of the abnormality.
At this time, the wakeup signal output multiplexing information calculation block 210 obtains the network address of the data transmission destination node (data reception node 100) from the transmission node storage block 290. For example, in FIG. 1, when the node 5 is the data transmission node 200 and the node 1 is a server terminal, the wake-up signal output multiplexing information calculation block 210 of the node 5 obtains the network address of the node 2 that is the parent node. To do.
Then, the wakeup signal output multiplexing information calculation block 210 multiplexes the data transmission destination node based on the subnetwork number of the data transmission destination node and the node number of the data transmission destination node specified as described above from the acquired network address. Calculation information is calculated. The multiplexing information of the data transmission destination node indicates the frequency channel and time slot used for transmitting the wakeup signal to the data transmission destination node.
Details of the multiplexing information will be described later.

<S220: Wake-up signal transmission process>
Next, in the data transmission node 200, the wakeup signal output block 220 transmits a wakeup signal to the data transmission destination node based on the multiplexing information of the data transmission destination node calculated by the wakeup signal output multiplexing information calculation block 210.
At this time, the wakeup signal output block 220 transmits a wakeup signal based on the frequency channel and time slot indicated by the multiplexing information of the data transmission destination node calculated by the wakeup signal output multiplexing information calculation block 210. For example, the wakeup signal output block 220 transmits a wakeup signal having a frequency corresponding to the frequency channel indicated by the multiplexing information. For example, the wakeup signal output block 220 transmits a wakeup signal in a time zone corresponding to the time slot indicated by the multiplexing information.

<S130: Wake-up signal detection process>
Next, in the data receiving node 100, the wakeup signal detection block 130 receives the wakeup signal transmitted from the data transmission node 200 based on the multiplexing information of the own node calculated by the wakeup signal detection multiplexing information calculation block 120 in S110. To detect.
For example, the wakeup signal detection block 130 receives only a signal having a frequency corresponding to the frequency channel indicated by the multiplexing information, and uses the received signal as the wakeup signal. Further, for example, the wakeup signal detection block 130 receives a signal only in a time zone corresponding to the time slot indicated by the multiplexing information, and uses the received signal as a wakeup signal.

<S140: ACTIVE mode switching process>
Next, in the data receiving node 100, the mode control block 110 sets the operation mode of the data receiving node 100 to the ACTIVE mode.
At this time, the mode control block 110 disables the wakeup signal detection block 130 and enables the data reception block 140.

<S230: Data transmission process>
Next, in the data transmission node 200, the data transmission block 230 transmits the generated data.

<S150: Data Reception Processing>
In the data receiving node 100, the data receiving block 140 receives the data transmitted from the data transmitting node 200.

In the data receiving node 100 that has received the data, the mode control block 110 switches to the SLEEP mode after completion of data reception or after a predetermined time has elapsed since switching to the ACTIVE mode in S140 (S120).
The data receiving node 100 that has received the data may transmit data to another node as the data transmitting node 200 as a relay node. For example, in FIG. 1, node 2 (relay terminal) that has received data from node 5 (sensor terminal) transmits the received data to node 1 (server terminal).

In the wireless communication method according to the first embodiment, the wakeup signal detection multiplexing information calculation block 120 of the data reception node 100 calculates in S110, and the wakeup signal output multiplexing information calculation block 210 of the data transmission node 200 calculates in S210. It has a feature in the conversion information.
Here, details of the multiplexed information will be described.

The multiplexing information calculated by the wakeup signal detection multiplexing information calculation block 120 and the wakeup signal output multiplexing information calculation block 210 indicates a frequency channel and a time slot applied to the wakeup signal.
The multiplexing information of the communication system 900 according to Embodiment 1 is uniquely determined by the subnetwork to which each node belongs and the node number in the subnetwork. Further, as described above, the subnetwork number and the node number of the communication system 900 according to Embodiment 1 are uniquely determined by the network address. That is, the communication system 900 according to the first embodiment is characterized in that the multiplexing information applied to the wakeup signal is uniquely determined from the network address.

  In the wireless communication method according to the first embodiment, since the multiplexing information can be calculated based on the network address of the own node or the network address of the destination node that is the data transmission destination, the multiplexing information of the destination node is obtained from the destination node. There is no need for acquisition or memory for storing and managing multiplexing information of the destination node (and multiplexing information of the own node). For this reason, the communication system 900 according to the first embodiment can be constructed at a very low cost and with low power.

  Equations 6, 7, and 8 below express frequency channel Ch (A) (channel number) and time slot Ts () as multiplexing information applied when transmitting a wake-up signal for switching node A to the ACTIVE mode. It is an example of an equation for calculating A) (time slot number) based on a subnetwork number Sid (A) and a node number Nsid (A) specified by a network address.

Ch (A) = Sid (A) (Formula 6)
Ts (A) = Ts (Ap) + Nsid (A) (Formula 7)
Ts (C) = 0 (Formula 8)
The symbols in the above formula mean the following.
Ch (A): Wake-up channel number of node A Ts (A): Wake-up time slot number of node A Ts (Ap): Time slot number of parent node of node A Ts (C): Time slot number of coordinator node

For example, in FIG. 1 and FIG. 2, when node 5 performs data transmission to node 2, wakeup signal detection multiplexing information calculation block 120 of node 2 and wakeup signal output multiplexing information calculation block 210 of node 5 As a result, the channel number “0” is calculated as the multiplexing information and the time slot number “1 (= 0 + 1)” is calculated as the multiplexing information according to Equation 7.
Then, the wakeup signal output block 220 of the node 5 transmits a wakeup signal having a frequency corresponding to the channel number “0” in a time zone (timing) corresponding to the time slot number “1”, and a wakeup signal detection block of the node 2 Reference numeral 130 detects a signal having a frequency corresponding to the channel number “0” and received in a time slot corresponding to the time slot number “1” as a wake-up signal.

FIG. 6 is a table showing multiplexing information (frequency channel, time slot) of each node in the first embodiment.
FIG. 6 shows multiplexing information (frequency channel, time slot) assigned to each node shown in FIG. 1 according to the above description.

  The calculation method of the frequency channel Ch and the time slot number Ts shown in the above formulas 6 to 8 is an example of the multiplexing information calculation method in the first embodiment. For example, “time slot number Ts = node number Nsid” Alternatively, the time slot number Ts may be a remainder obtained by dividing the value represented by the above expression 7 by the maximum number of child nodes Cm connected to one parent node described above.

The network address assignment method according to the present embodiment is an example for simplifying the description.
When assigning network addresses, for example, in a wireless network in which correspondence between a position on the tree and a network address is obtained by performing assignment using a network tree as shown in FIG. 1, the subnetwork number and the subnetwork The node number is uniquely determined from the network address. If it is a communication system using such a network, the multiplexing information allocating method in the present embodiment can be applied. In other words, the multiplexing information allocating method according to the present embodiment uses a cluster tree type network tree in which a network address of one or more child devices corresponds to a network address of one parent device. The present invention can be applied to the used wireless network system. For example, in a communication system in which network addresses are assigned according to the ZigBee standard (version 1.0), the multiplexed information assignment method in the present embodiment can be applied.
The network tree is a tree for address allocation, and the data communication path does not necessarily need to use the tree structure for address allocation. For example, the multiplexed information allocating method according to the present embodiment can be applied to a network system in which a mesh network is provided for a data communication path separately from a network tree for address allocation.

In the present embodiment, the wireless terminal (data reception node 100) used in the wireless network system that assigns network addresses using a cluster tree type address tree has been described.
The wireless terminal has a sleep mode in which only some of its components operate, and in the sleep mode, means for calculating multiplexing information from its own network address (wakeup signal detection multiplexing information calculation block) 120), and the radio circuit unit (wake-up signal detection block 130) performs detection processing of the received radio wave (wake-up signal detection processing) based on the multiplexed information, and detects a predetermined wake-up signal by the detection processing. . Then, when the wireless circuit unit detects the wake-up signal, the wireless terminal enters an active mode in which data communication can be performed from the sleep mode.

  Further, in the present embodiment, when a transmission request is generated, it has means (wake-up signal output multiplexing information calculation block 210) for calculating multiplexing information of the wake-up signal from the network address of the destination wireless terminal, The wireless communication device (data transmission node 200) that transmits a wake-up signal based on the multiplexing information has been described.

According to the present embodiment, the wakeup signal detection multiplexing information calculation block 120 obtains multiplexing information used for communication of the wakeup signal based on the network address of its own device. -It is possible to prevent unnecessary power consumption by switching to the mode.
Further, for example, it is possible to eliminate the need for communication between the data receiving node 100 and the data transmitting node 200 in order to notify the multiplexed information.
Further, for example, it is possible to eliminate the need for the data transmission node 200 to store and manage the multiplexed information separately from the network address for the data reception node 100.

Embodiment 2. FIG.
Since multiplexing information (frequency channel, time slot) is generally finite, unique multiplexing information may not be assigned to all nodes. For example, in the first embodiment, when there is a relationship of the following formulas 9 and 10, a unique frequency channel Ch and time slot Ts cannot be assigned to all nodes.

Sid (A)> Chmax (Formula 9)
Ts (Ap) + Nsid (A)> Tsmax (Formula 10)
The symbols in the above formula mean the following.
Chmax: Maximum value of frequency channel Ch that can be used in communication system 900 Tsmax: Maximum value of time slot Ts that can be divided in communication system 900

  In such a case, the multiplexed information is reused, resulting in a plurality of nodes having the same multiplexed information. For example, when unique multiplexing information cannot be assigned to all nodes in the first embodiment, the frequency channel Ch and the time slot Ts are assigned to each node according to the following expressions 11 and 12, and the same There are a plurality of nodes having the frequency channel Ch and the time slot Ts.

Ch (A) = Sid (A)% Chmax (Formula 11)
Ts (A) = (Ts (Ap) + Nid (A))% Tsmax (Formula 12)

  For this reason, when a wake-up signal interferes, a node that is not a communication target is woken up wastefully, and that node consumes wasteful power.

  Therefore, in addition to the multiplexing information allocation method described in the first embodiment, in this embodiment, a mechanism for reallocating multiplexing information in order to suppress useless wakeup will be described.

FIG. 7 is a configuration diagram of a communication system 900 according to the second embodiment.
As shown in FIG. 7, a communication system 900 (an example of a wireless network system or a communication network) according to the second embodiment includes a host computer 300 connected to the node 1 serving as a network coordinator.
The host computer 300 in the second embodiment reallocates the multiplexed information for each node.

FIG. 8 is a functional configuration diagram of the data transmission / reception node 400 according to the second embodiment.
In FIG. 8, each functional configuration of the data receiving node 100 and each functional configuration of the data transmitting node 200 shown in the first embodiment are collectively shown as a data transmission / reception control block 401. The data transmission / reception control block 401 includes the mode control block 110, the wakeup signal detection multiplexed information calculation block 120, the wakeup signal detection block 130, the data reception block 140, and the reception node storage block 190 described in the first embodiment. The data transmission / reception control block 401 includes the wakeup signal output multiplexing information calculation block 210, the wakeup signal output block 220, the data transmission block 230, and the transmission node storage block 290 described in the first embodiment.
In addition to the data transmission / reception control block 401, the data transmission / reception node 400 (an example of a wireless communication device) includes a new entry processing block 451, an RSSI value acquisition block 452, a location information acquisition block 453, and a multiplexed information reallocation request block 454. And an address change processing block 455.

The new entry processing block 451 acquires the network address of the own node from the parent node by an arbitrary entry procedure using the CPU and the communication device when the own node newly enters the network.
The RSSI value acquisition block 452 acquires an RSSI (Receive Signal Strength Indication) value with a node that can be a parent in the vicinity of the own node using a CPU and a communication device. The RSSI value acquisition block 452 can use the value when the RSSI value is acquired in the entry procedure by the new entry processing block 451.
The position information acquisition block 453 acquires the position information of the own node by an arbitrary method using the CPU. For example, the position information acquisition block 453 acquires the position information of the own node by a technique such as triangulation using an RSSI value with a GPS (Global Positioning System) or a node serving as a reference of position information. When the position information acquisition block 453 acquires the position information of its own node by GPS positioning, the data transmission / reception node 400 includes a GPS receiver. Further, the host computer 300 may acquire the position information of the node using the RSSI value acquired by the RSSI value acquisition block 452 instead of the position information acquisition block 453. That is, the data transmission / reception node 400 may be configured not to include the position information acquisition block 453.
A multiplexing information reallocation request block 454 (an example of a reallocation request unit) transmits a multiplexing information reallocation request to the host computer 300 using a transmitter. As described in Embodiment 1 above, in this wireless communication method, the multiplexing information is specified by the network address. Therefore, in this embodiment, the reallocation of the multiplexing information is synonymous with the reallocation of the network address. It is.
The address change processing block 455 receives an address change notification indicating the new network address of the own node from the host computer 300 using the communication device, and cancels the parent-child relationship with the parent node at that time using the CPU, and Build a parent-child relationship with the parent node corresponding to the network address. The address change processing block 455 notifies the wakeup signal detection multiplexing information calculation block 120 included in the data transmission / reception control block 401 that the network address of the own node has been updated. The wakeup signal detection multiplexing information calculation block 120 calculates new multiplexing information for detecting the wakeup signal based on the new network address of the own node.

FIG. 9 is a functional configuration diagram of the host computer 300 according to the second embodiment.
The host computer 300 that reallocates multiplexing information to each node will be described below with reference to FIG.

  The host computer 300 includes a multiplexed information reallocation request reception block 310, a multiplexed information calculation block 320, an address change instruction block 330 and a host storage block 390.

The multiplexed information reallocation request receiving block 310 (an example of a reallocation request receiving unit) receives the multiplexed information reallocation request transmitted from the data transmitting / receiving node 400 using a communication device.
The multiplexing information calculation block 320 (an example of a parent selection unit) uses a position information table 391 that indicates the position information of each node stored in the host storage block 390, and nodes having close positions constitute a subnetwork. Thus, the address tree is recalculated using the CPU.
In the address change instruction block 330 (an example of an address notification unit), when a difference from the address tree before calculation occurs in the address tree indicated by the calculation result of the multiplexing information calculation block 320, the network address is changed. Inform the node of the changed network address using the transmitter.
The host storage block 390 (position information storage unit) stores a position information table 391 indicating position information of each node, a multiplexing information calculation result of the multiplexing information calculation block 320, and the like.

FIG. 10 is a flowchart showing a multiplexed information reallocation method according to the second embodiment.
The multiplexing information reallocation method between the host computer 300 and the data transmission / reception node 400 in the second embodiment will be described below with reference to FIG.
Each block of the host computer 300 and the data transmission / reception node 400 executes the following processing using hardware such as a CPU and a communication device.

<S310: New entry process>
First, in the data transmission / reception node 400, the new entry processing block 451 causes the own node to enter the network by an arbitrary entry procedure, and acquires the network address of the own node from the parent node.
For example, the new entry processing block 451 causes the own node to enter the network according to the following entry procedure, and acquires the network address of the own node.

(1) The new entry processing block 451 broadcast-transmits a new entry request command to nodes that can be neighboring parents.
(2) In the case of (1), the new entry processing block 451 uses, for example, a non-multiplexed wakeup signal as shown in paragraph [0008] when the peripheral nodes are set to the SLEEP mode. Wake up surrounding nodes.
(3) A node that can be a parent in the vicinity of receiving a new entry request command transmits a response indicating that it can be accepted as a child node by the new entry node to the new entry node by a wireless packet. A node that can be a parent is a node in which the number of child nodes assigned a network address is less than the maximum number of child nodes Cm.
(4) The new entry processing block 451 receives a response packet from each node that can be a parent, and selects one parent node in consideration of communication quality such as an RSSI value of the response packet. Then, the new entry processing block 451 issues an entry command to the selected parent node.
(5) The parent node that has received the entry command selects one unassigned network address from among the network addresses for child nodes that it manages for the new entry node, and selects the selected network address. Notify new entry nodes.
For example, in this way, the new entry processing block 451 newly enters the network and acquires a network address.

<S320: RSSI value transmission processing>
Next, in the data transmission / reception node 400, the RSSI value acquisition block 452 acquires the RSSI value with the parent node when newly entering the network in S310. Then, the RSSI value acquisition block 452 transmits the acquired RSSI value to the host computer 300. The host computer 300 stores the RSSI value received from each node in the host storage block 390.
For example, the RSSI value acquisition block 452 indicates the strength of the received radio wave at the time of receiving the response packet received from the parent node in (4) above or the packet notifying the network address transmitted from the parent node in (5) above. Detect as. There is a correlation between the RSSI value (= received radio wave intensity) and the distance, and the RSSI value with the parent node becomes smaller as the distance with the parent node becomes longer. Therefore, it is possible to calculate the distance from three or more reference nodes (for example, each node that can be a parent) whose position is known based on the RSSI value, and to calculate the position of the node by multi-side survey.

<S330: Position Information Transmission Process>
Next, in the data transmission / reception node 400, the position information acquisition block 453 calculates the position of the own node by a positioning method using GPS or a multi-side surveying method using RSSI values. Then, the position information acquisition block 453 transmits the calculated position of the own node to the host computer 300. The host computer 300 stores the position information received from each node in the host storage block 390.
However, when the host computer 300 calculates the position information of each node using the RSSI value received from each node, the position information calculation process (S330) by the position information acquisition block 453 may not be executed.

<S340: Reallocation request transmission process>
Next, in the data transmission / reception node 400, the multiplexed information reallocation request block 454 transmits the multiplexed information reallocation request to the host computer 300 of the newly entered network. As described above, in this embodiment, the reallocation of multiplexed information is synonymous with the reallocation of network addresses.

<S410: Reallocation Request Reception Processing>
Next, in the host computer 300, the multiplexed information reallocation request receiving block 310 receives the multiplexed information reallocation request transmitted from the data transmitting / receiving node 400.

<S420: Address Tree Recalculation Processing>
Next, in the host computer 300, the multiplexing information calculation block 320 uses the position information table 391 indicating the position information of each node stored in the host storage block 390, so that the nodes with close positions (distances close to each other) Recalculates the address tree to form a subnetwork. At this time, the multiplexing information calculation block 320 calculates the address tree so that the RSSI value between the nodes in the parent-child relationship indicates a radio wave level equal to or higher than a predetermined value, and the parent node and the child node are mutually connected in the calculated address tree. Enable communication.

FIG. 11 is a diagram illustrating an example of the position information table 391 according to the second embodiment.
FIG. 12 is a diagram illustrating an arrangement example of each data transmission / reception node 400 in the second embodiment.
The host computer 300 stores the position information received from each data transmission / reception node 400 shown in FIG. 12 in the position information transmission process (S330) as a position information table 391 as shown in FIG. In the address tree recalculation process (S420), the multiplexing information calculation block 320 recalculates the address tree using the position information table 391. Further, the host computer 300 calculates the position of each data transmission / reception node 400 based on the RSSI value received from each data transmission / reception node 400 shown in FIG. 12 in the RSSI value transmission process (S320), and the calculated position information is shown in FIG. You may memorize | store as the positional information table 391 as shown.

FIG. 13 is a diagram illustrating an example of an address tree before recalculation according to the second embodiment.
In the address tree recalculation process (S420), the multiplexing information calculation block 320 recalculates the address tree by the following process on the address tree as shown in FIG. 13, for example.

Here, the premise of the address tree recalculation processing example described below is shown.
(A) In FIG. 13, Ndn (n = 0 to 3) is a reference node, and the connection between these reference nodes is a fixed connection (that is, a connection that is not subject to address recalculation).
(B) In FIG. 13, Ntn (n = 0 to 7) is a node whose connection is not fixed (that is, an address recalculation target).
(C) In the network of this example, only the reference node is defined as a node that can be a parent node.
(D) Further, in the network of FIG. 13, Cm = 3 is set, and there is a restriction that one node can have a maximum of 3 child nodes.

  Based on the above assumptions, the procedure for recalculating the address tree when the node Nt7 newly enters the network composed of the nodes Nd0 to Nd5 and the nodes Nt0 to Nt6 shown in FIG. 13 will be described below.

(1) First, the node Nt7 enters the network. At this point, since the node Nd3 located closest to the node Nt7 already has three child nodes (node Nt4, node Nt5, and node Nt6), a response packet indicating that the node Nd3 can be a parent node is sent to the node Nt7. Is not transmitted (see S310 (3)). That is, the node Nt7 cannot enter the network as a child node of the node Nd3. Therefore, the node Nt7 enters the network as a child node of the node Nd1, for example.
(2) Next, the node Nt7 acquires its own position information. Regardless of the acquisition means, GPS positioning or positioning based on the RSSI value may be used. As a result, the node Nt7 obtains coordinates (80, 120) as its own position information, and sends this position information to the host computer 300 (S330). Also, the node Nt7 makes a multiplexing information reassignment request to the host computer 300 (S340).
(3) Upon receiving this, the host computer 300 gives priority to the nodes Nt0 to Nt7 in the order of position and lists nodes that can become parent nodes. Here, those whose RSSI values are not at a predetermined level are excluded even if their positions are close. An example of the result of listing is shown in FIG.
FIG. 14 is a table showing an example of the parent node candidate list 392 in the second embodiment. The parent node candidate list 392 is stored in the host storage block 390.
(4) Here, when the node Nt0 to the node Nt7 are connected to the parent node candidate having the highest priority, if the condition of the number of child nodes ≦ Cm is satisfied, the address tree creation is completed.
(5) In (4), when the creation of the address tree is not completed (the number of child nodes> Cm), the child node having only one candidate is determined with priority. In the parent node candidate list 392 shown in FIG. 14, since the node Nt6 has only the node Nd3 as the connection candidate, the connection with the node Nd3 as the parent node is determined. When the parent node is not different from the parent node before recalculation, the same network address as before the recalculation is assigned to the child node.
(6) Next, for the nodes Nd0 to Nd4 that are the parent nodes, the connection relation is determined in the order of the nodes having the largest number of connection candidates. In this example, the node Nd3, which is the first candidate of four child nodes and the second candidate of two child nodes, corresponds to this. The node Nd3 has already been determined to connect the node Nt6 as a child node in (5), and the remaining two child nodes are set as “parent node candidates with the highest priority” (first candidate in FIG. 14). The node Nt4, the node Nt5, and the node Nt7 are selected. When the number of child nodes that are “parent node candidates with the highest priority” is greater than the number of child nodes that can be connected to the parent node, the children from the parent node in ascending order of distance (in descending order of RSSI value) Select a node. In FIG. 14, the node Nt4 and the node Nt7 are selected as child nodes in order of distance from the node Nd3.
(7) The node that could not be connected to the first candidate in (6) moves up the parent node candidate with the highest priority, returns to (4), and continues processing. In FIG. 14, the node Nd2 (second candidate) is moved up as the parent node candidate having the highest priority of the node Nt5, and the process returns to the process (4).
In this example, the creation of the address tree is completed by the second process (4).
FIG. 15 shows an address tree after recalculation for the address tree shown in FIG.
FIG. 15 is a diagram illustrating an example of an address tree after recalculation according to the second embodiment.

  In FIG. 10, the description of the multiplexing information reallocation method will be continued.

<S430: Address Change Notification Process>
When a difference from the address tree before the calculation occurs in the address tree recalculated by the multiplexing information calculation block 320 in S420, the address change instruction block 330 displays the network address for each node in which the connected node has changed. Notify the change and newly assigned network address. In the above example, the parent node is changed in the node Nt5 and the node Nt7, and the network address is changed in accordance with the change in the parent node.

<S350: Address change processing>
Next, in the data transmission / reception node 400, the address change processing block 455 receives the address change notification from the host computer 300, cancels the parent-child relationship with the parent node at that time, and sets the parent node corresponding to the new network address. Build parent-child relationships.
When the address change processing block 455 receives the address change notification, the address change processing block 455 deletes the network address of the own node from the receiving node storage block 190 included in the data transmission / reception control block 401 and cancels the parent-child relationship with the parent node. The new network address indicated by the change notification is stored in the receiving node storage block 190 to establish a parent-child relationship with the new parent node.

<S360: Multiplexing information calculation process>
The address change processing block 455 notifies the wakeup signal detection multiplexing information calculation block 120 included in the data transmission / reception control block 401 that the network address of the own node has been updated, and the wakeup signal detection multiplexing information calculation block. 120 calculates new multiplexing information for detecting the wakeup signal based on the new network address.

According to the above procedure, in the communication system 900 according to the present embodiment, each time a new data transmission / reception node 400 joins, the address tree is reconfigured so that each data transmission / reception node 400 that constitutes a member of the subnetwork is arranged in a small area. Will build. In addition, placing the subnetwork members in a small area means reducing the interference area of the wake-up signal. That is, the multiplexed information reallocation method of the present embodiment can obtain an effect of making it difficult to interfere with the wakeup signal.
For example, in FIG. 16, it is assumed that each child node transmits a wakeup signal to the parent node Nd1. Further, it is assumed that the multiplexing information is duplicated between the parent node Nd1 and the node Nt9 belonging to another subnetwork. Here, as shown in the left diagram, when the nodes Nt0, Nt1, and Nt2 that are located away from the parent node Nd1 constitute a sub-network as a child node of the parent node Nd1 (left diagram), each child node forms. The radio wave arrival area (interference area) for transmitting the wakeup signal is widened, and the wakeup signal for the parent node Nd1 is received up to the node Nt9 that is not the object of data communication, and the active mode is switched. However, as shown in the right figure, the radio wave arrival area can be narrowed by configuring the sub-network in the nodes Nt3, Nt4, and Nt5 located near the parent node Nd1, and the wakeup signal for the parent node Nd1 is sent to the node Nt9. Therefore, the node Nt9 that is not the object of data communication does not wastefully switch to the active mode.
As a result, the communication system 900 according to the present embodiment can prevent power consumption of the node due to useless wakeup.

A further advantage of this embodiment is that, as described above, the sub-network members can be arranged in a smaller area, so that the output radio wave intensity of the wake-up signal can be reduced, or the detected radio wave level of the wake-up signal can be set high. It is.
For example, as shown in FIG. 17, when nodes Nt3, Nt4, and Nt5 located near the parent node Nd1 form a subnetwork, the radio wave arrival areas of the nodes Nt3, Nt4, and Nt5 include the parent node Nd1. Can be small. That is, the output radio wave intensity of the wakeup signal can be reduced to such an extent that the wakeup signal reaches the parent node Nd1. Further, when the nodes Nt3, Nt4, and Nt5 located near the parent node Nd1 form a subnetwork, the distance until the wakeup signal reaches the parent node Nd1 is short, so that the attenuation of the wakeup signal is small. Therefore, when the output radio wave intensity of the wakeup signal is not reduced, the detection radio wave level of the wakeup signal when reaching the parent node Nd1 is increased, and the detection accuracy of the wakeup signal by the parent node Nd1 is increased.
As a result, the communication system 900 according to the present embodiment further prevents the wake-up signal from interfering, and prevents power consumption due to useless wake-up.

Embodiment 3 FIG.
In the third embodiment, a mode corresponding to a case where a communication error occurs between nodes due to a change in the communication environment or a failure of the node will be described.
Hereinafter, matters different from those in the first embodiment and the second embodiment will be described, and matters that will not be described are the same as those in the first embodiment or the second embodiment.

FIG. 18 is a functional configuration diagram of the data transmission / reception node 400 according to the third embodiment.
The data transmission / reception node 400 according to the third embodiment is characterized by including a communication error detection block 456 with respect to the data transmission / reception node 400 according to the second embodiment.

  A communication error detection block 456 (an example of a communication error detection unit) detects a communication error at the time of data transmission using a CPU and a communication device.

FIG. 19 is a flowchart showing a multiplexed information reallocation method according to the third embodiment.
A multiplexing information reallocation method between the host computer 300 and the data transmission / reception node 400 in the third embodiment will be described below with reference to FIG.

<S510: Communication error detection processing>
A communication error detection block 456 detects a communication error during data transmission.
For example, in the communication system 900 for data communication by TCP / IP, the communication error detection block 456 executes error detection processing in TCP / IP communication.

When the communication error detection block 456 detects a communication error, the multiplexed information reallocation request block 454 transmits a multiplexed information reallocation request to the host computer 300 (S340), and the host computer 300 performs address tree recalculation. Then, an address change notification is transmitted to the data transmitting / receiving node 400 in which the network address has changed (S410 to S430), and the data transmitting / receiving node 400 calculates new multiplexing information using the new network address (S350). ~ S360).
Here, when recalculating the address tree, the current parent node is excluded from the parent node candidates, and a new parent node is assigned to the data transmission / reception node 400.
As described above, the communication system 900 according to Embodiment 3 can construct a communication network suitable for power saving even when a communication error occurs.

Embodiment 4 FIG.
In a system in which the node density (the number of nodes with respect to the usable communication band [frequency, time slot]) is high with respect to the multiplexed information, wasteful wakeup of the node is inevitable due to interference of the wakeup signal. . Therefore, in the communication system 900 according to the second embodiment, the interference area of the wakeup signal is reduced using the position information. In other words, this corresponds to suppressing the number of nodes that interfere with each other.
On the other hand, the amount of communication of each node is a problem of system dependency, and in the case where the communication frequency of nodes that are in a relationship with which the wakeup signal interferes is very high, the number of nodes with which the wakeup signal interferes according to the second embodiment. Even if the number is reduced, the number of unnecessary wakeups increases.
Therefore, in the present embodiment, a mode corresponding to useless wakeup that cannot be dealt with by reducing the interference area will be described.
Furthermore, in this embodiment, a method for grasping the power consumption of a node will be described.

FIG. 20 is a functional configuration diagram of the data transmission / reception node 400 according to the fourth embodiment.
The data transmission / reception node 400 according to the fourth embodiment is characterized by including a wake-up signal interference detection block 457 as compared with the data transmission / reception node 400 according to the third embodiment.

  The wake-up signal interference detection block 457 (an example of a signal interference detection frequency counting unit) detects whether or not the number of times of wake-up of the own node has exceeded a predetermined threshold using the CPU. The wakeup signal interference detection block 457 transmits the number of times of wakeup uselessly to the host computer 300 using a communication device.

FIG. 21 is a flowchart showing a multiplexed information reallocation method according to the fourth embodiment.
A multiplexing information reallocation method between the host computer 300 and the data transmission / reception node 400 in the fourth embodiment will be described below with reference to FIG.

<S610: Interference detection processing>
The wake-up signal interference detection block 457 counts the number of times that the node has been woken up even though it is not involved in communication, and if the counted number exceeds the number of times allowed per predetermined time determined in advance by the system, It is determined that interference has occurred.
For example, in the data transmission / reception control block 401, the wake-up signal interference detection block 457 performs a predetermined operation after the mode control block 110 shifts the operation mode of its own node to the active mode when the wake-up signal detection block 130 detects the wake-up signal. If the data reception block 140 does not receive data even after the time elapses, it is determined that the node has been woken up regardless of communication, and the counting is performed. Then, the count number is compared with a predetermined allowable number at a predetermined time interval, and when the count number exceeds the allowable number, the wake-up signal interference has occurred in the multiplexed information reallocation request block 454 To be notified.

When the wakeup signal interference detection block 457 detects interference of the wakeup signal, the multiplexed information reallocation request block 454 transmits a multiplexed information reallocation request to the host computer 300 (S340), and the host computer 300 transmits the address tree. Recalculation is performed, and an address change notification is transmitted to the data transmission / reception node 400 in which the network address has changed (S410 to S430), and the data transmission / reception node 400 calculates new multiplexing information using the new network address. (S350 to S360).
Here, when recalculating the address tree, for example, another network address managed by the same parent node is assigned to the data transmission / reception node 400, or the current parent node is excluded from the parent node candidates and a new parent address is assigned. A node is assigned to the data transmission / reception node 400.
As described above, the communication system 900 according to the fourth embodiment can construct a communication network more suitable for power saving according to the occurrence of interference of a wakeup signal.

  Next, a method for grasping the power consumption of each data transmission / reception node 400 will be described.

FIG. 22 is a functional configuration diagram of the host computer 300 according to the fourth embodiment.
The host computer 300 according to the fourth embodiment is characterized by including a maintenance interface block 340 with respect to the host computer 300 according to the second embodiment.

  The maintenance interface block 340 (interference power consumption calculation unit) calculates the power consumption of the data transmission / reception node 400 using the CPU based on the number of times that the data transmission / reception node 400 is woken up uselessly.

Since useless wakeup due to wakeup interference is power consumption unrelated to system operation, it is difficult to predict the battery life of each data transmitting / receiving node 400 due to the occurrence of wakeup interference.
Therefore, the wake-up signal interference detection block 457 of the data transmission / reception node 400 notifies the host computer 300 of the counted number of interferences of the wake-up signal (total count number after battery charging, signal interference detection number).
Further, in the host computer 300, the maintenance interface block 340 multiplies the notified number of times of interference of the wakeup signal by the power consumption per interference determined in advance to obtain the power consumption value (interference power consumption) due to the interference of the wakeup signal. calculate.
Then, the host computer 300 uses the power consumption value (for example, the power consumption value based on the estimated data transmission / reception frequency generated per unit time) associated with the system operation designed in advance and the power consumption value and wakeup signal determined by the actual data transmission / reception frequency. The power consumption value due to interference is added up. This total value means the power consumption of the data transmission / reception node 400, that is, the degree of battery consumption.
As a result, the system administrator can accurately determine the replacement time of the battery based on the total value, and it is possible to improve the reliability of the communication system 900 and suppress an increase in maintenance costs.

In each of the embodiments, the low power consumption wireless terminals (the data reception node 100, the data transmission node 200, and the data transmission / reception node 400) having a sleep mode in which only a part of its own components operate are described.
In the sleep mode, the wireless terminal performs wake-up signal detection processing (wake-up signal detection processing) for the time slot and the frequency channel based on the multiplexing information assigned to the wireless terminal, and outputs the wake-up signal. When detected, the components other than the part are activated to switch from the sleep mode to the active mode in which data communication is possible.
Further, in order to obtain multiplexed information of a wake-up signal to which the wireless terminal is autonomously assigned, a wireless terminal actively requests optimization of multiplexed information according to its own wireless environment (multiplexed information re-transmission). An allocation request block 454) and means (address change processing block 455) capable of changing its own multiplexing information in accordance with the multiplexing information designated by the host computer 300.
Further, the host computer 300 receives the request for optimization of the multiplexing information, and determines the multiplexing information of the wake-up signal based on the position information and communication environment of the low power consumption wireless terminals constituting the system. Means (multiplexing information calculation block 320) and means for notifying the determined multiplexing information to the wireless terminal (address change instruction block 330).

FIG. 23 is a diagram illustrating an example of hardware resources of the data reception node 100, the data transmission node 200, the host computer 300, and the data transmission / reception node 400 in the embodiment.
In FIG. 23, a data reception node 100, a data transmission node 200, a host computer 300, and a data transmission / reception node 400 are a CPU 911 (Central Processing Unit, Central Processing Unit, Processing Unit, Arithmetic Unit, Microprocessor, Microprocessor that executes a program. Computer or processor). The CPU 911 is connected to the ROM 913, the RAM 914, the communication board 915, and the magnetic disk device 920 via the bus 912, and controls these hardware devices. Instead of the magnetic disk device 920, another storage device (for example, a semiconductor memory such as a RAM or a flash memory) may be used.
The RAM 914 is an example of a volatile memory. The storage medium of the ROM 913 and the magnetic disk device 920 is an example of a nonvolatile memory. These are examples of a storage device, a storage device, or a storage unit. A storage device in which input data is stored is an example of an input device, an input device, or an input unit, and a storage device in which output data is stored is an example of an output device, an output device, or an output unit.
The communication board 915 is an example of an input / output device, an input / output device, or an input / output unit.

  The communication board 915 is wired or wirelessly connected to a communication network such as a LAN (Local Area Network), the Internet, a WAN (Wide Area Network) such as ISDN, and a telephone line.

  The magnetic disk device 920 stores an OS 921 (operating system), a program group 923, and a file group 924. The programs in the program group 923 are executed by the CPU 911 and the OS 921.

  The program group 923 stores programs that execute the functions described as “˜unit” and “˜block” in the embodiment. The program is read and executed by the CPU 911.

In the file group 924, in the embodiment, results such as “determination result of”, “calculation result of”, “processing result of”, etc. when the functions of “˜part” and “˜block” are executed. Data, data to be passed between programs that execute the functions of "~ part" and "~ block", other information, data, signal values, variable values, and parameters are "~ file" and "~ database" items. Is remembered as Network address, multiplexing information, location information, RSSI value, etc. are examples of what is included in the file group 924.
The “˜file” and “˜database” are stored in a recording medium such as a disk or a memory. Information, data, signal values, variable values, and parameters stored in a storage medium such as a disk or memory are read out to the main memory or cache memory by the CPU 911 via a read / write circuit, and extracted, searched, referenced, compared, and calculated. Used for CPU operations such as calculation, processing, output, printing, and display. Information, data, signal values, variable values, and parameters are temporarily stored in the main memory, cache memory, and buffer memory during the CPU operations of extraction, search, reference, comparison, operation, calculation, processing, output, printing, and display. Is remembered.
Also, the arrows in the flowcharts described in the embodiments mainly indicate input / output of data and signals, and the data and signal values are recorded in the memory of the RAM 914, the magnetic disk of the magnetic disk device 920, and other recording media. . Data and signal values are transmitted online via a bus 912, signal lines, cables, or other transmission media.

  In addition, what has been described as “˜unit” and “˜block” in the embodiments may be “˜circuit”, “˜device”, “˜device”, and “˜step”, “˜”. “Procedure” and “˜Process” may be used. That is, what has been described as “˜unit” and “˜block” may be realized by firmware stored in the ROM 913. Alternatively, it may be implemented only by software, or only by hardware such as elements, devices, substrates, and wirings, by a combination of software and hardware, or by a combination of firmware. Firmware and software are stored as programs on a magnetic disk or other recording medium. The wireless communication program is read by the CPU 911 and executed by the CPU 911. That is, the program causes the computer to function as “˜part” and “˜block”. Alternatively, the procedure or method of “˜part” and “˜block” is executed by a computer.

FIG. 3 shows an example of a communication system 900 having a network address configuration in the first embodiment. 4 is a table showing a network address, a subnetwork number, and a node number of each node in the first embodiment. 2 is a functional configuration diagram of a data reception node 100 according to Embodiment 1. FIG. 2 is a functional configuration diagram of a data transmission node 200 according to Embodiment 1. FIG. 3 is a flowchart illustrating a wireless communication method according to Embodiment 1. The table | surface which shows the multiplexing information (frequency channel, time slot) of each node in Embodiment 1. FIG. FIG. 3 is a configuration diagram of a communication system 900 according to a second embodiment. FIG. 11 is a functional configuration diagram of a data transmission / reception node 400 according to the second embodiment. FIG. 6 is a functional configuration diagram of a host computer 300 according to the second embodiment. 9 is a flowchart showing a multiplexed information reallocation method in the second embodiment. FIG. 10 shows an example of a position information table 391 in Embodiment 2. FIG. 10 is a diagram illustrating an arrangement example of data transmission / reception nodes 400 according to the second embodiment. FIG. 10 shows an example of an address tree before recalculation in the second embodiment. 10 is a table showing an example of a parent node candidate list 392 in the second embodiment. FIG. 10 shows an example of an address tree after recalculation in the second embodiment. The figure which shows the interference area of the wakeup signal in Embodiment 2. FIG. The figure which shows the interference area of the wakeup signal in Embodiment 2. FIG. FIG. 11 is a functional configuration diagram of a data transmission / reception node 400 according to the third embodiment. 10 is a flowchart showing a multiplexed information reallocation method in the third embodiment. FIG. 10 is a functional configuration diagram of a data transmission / reception node 400 according to the fourth embodiment. 10 is a flowchart showing a multiplexed information reallocation method in the fourth embodiment. FIG. 11 is a functional configuration diagram of a host computer 300 according to the fourth embodiment. The figure which shows an example of the hardware resource of the data receiving node 100 in the embodiment, the data transmission node 200, the host computer 300, and the data transmission / reception node 400.

Explanation of symbols

  100 data reception node, 110 mode control block, 120 wakeup signal detection multiplexing information calculation block, 130 wakeup signal detection block, 140 data reception block, 190 reception node storage block, 200 data transmission node, 210 wakeup signal output multiplexing information calculation Block, 220 wake-up signal output block, 230 data transmission block, 290 transmission node storage block, 300 host computer, 310 multiplexed information reallocation request reception block, 320 multiplexed information calculation block, 330 address change instruction block, 390 host storage block 391 Location information table, 392 Parent node candidate list, 400 data transmission / reception node, 401 data transmission / reception control block, 451 Processing block, 452 RSSI value acquisition block, 453 position information acquisition block, 454 multiplexed information reallocation request block, 455 address change processing block, 456 communication error detection block, 457 wakeup signal interference detection block, 900 communication system, 911 CPU, 912 bus, 913 ROM, 914 RAM, 915 communication board, 920 magnetic disk device, 921 OS, 923 program group, 924 file group.

Claims (7)

A host computer that is connected to communicate with a plurality of wireless communication devices that are distinguished as either a parent device or a child device;
A network address of each parent device, a network address associated with each network address of each parent device, and a location information storage unit that stores location information of each of the plurality of wireless communication devices;
A parent selection unit that acquires position information of each of the plurality of wireless communication devices from the position information storage unit, and that uses a CPU to select a parent device that is close to the child device based on the acquired position information;
The network address associated with the network address of the parent device selected by the parent selection unit among the network addresses associated with the network addresses of the respective parent devices is notified to the child device using a communication device. A host computer, comprising: an address notification unit that causes the child device to use the network address notified by the child device as the network address of the child device. A wireless network system having a host computer and a plurality of wireless communication devices distinguished as either a parent device or a child device;
The host computer
A network address of each parent device, a network address associated with each network address of each parent device, and a location information storage unit that stores location information of each of the plurality of wireless communication devices;
A parent selection unit that acquires position information of each of the plurality of wireless communication devices from the position information storage unit, and that uses a CPU to select a parent device that is close to the child device based on the acquired position information;
The network address associated with the network address of the parent device selected by the parent selection unit among the network addresses associated with the network addresses of the respective parent devices is notified to the child device using a communication device. An address notification unit that causes the child device to use the network address notified by the child device as the network address of the child device ;
Each of the plurality of wireless communication devices
Multiplexing information for determining multiplexing information of wireless communication used for communication of a wake-up signal indicating the start of data communication from another device to its own device using a CPU (Central Processing Unit) based on its own network address A calculation unit;
A wake-up signal detection unit for detecting a wake-up signal for the device itself using a communication device based on the multiplexing information obtained by the multiplexing information calculation unit;
A mode control unit that switches the operation mode of its own device from a sleep mode in which the data communication function is suspended to an active mode in which the data communication function is activated using the CPU when the wakeup signal detection unit detects a wakeup signal; ,
A wireless network system, comprising: a data receiving unit that receives communication data transmitted from another device after being switched to the active mode by the mode control unit using a communication device . The plurality of wireless communication devices are:
3. The wireless network system according to claim 2, wherein a cluster tree type wireless network is configured in which one or more child devices are related to one parent device by a network address. The wireless communication device further includes:
A communication error detection unit that detects a communication error using a CPU;
A re-allocation request unit that transmits a new parent device allocation request to the host computer using a communication device when the communication error detection unit detects a communication error;
The host computer further includes:
A re-assignment request receiving unit that receives the assignment request transmitted by the wireless communication device using a communication device;
The parent selection unit selects a parent device other than the parent device related to the wireless communication device as a parent device of the wireless communication device when the reallocation request receiving unit receives the allocation request. The wireless network system according to claim 2 or 3 . The wireless communication device further includes:
When the wake-up signal detection unit detects a wake-up signal transmitted to another device based on the same multiplexing information as that of its own device, a new parent device allocation request is transmitted to the host computer using a communication device. With a reallocation request section,
The host computer further includes:
A re-assignment request receiving unit that receives the assignment request transmitted by the wireless communication device using a communication device;
The parent selection unit selects a parent device other than the parent device related to the wireless communication device as a parent device of the wireless communication device when the reallocation request receiving unit receives the allocation request. The wireless network system according to claim 2 or 3 . The wireless communication device further includes:
When the wake-up signal detection unit detects a wake-up signal transmitted to another device based on the same multiplexing information as that of its own device, a new network address allocation request is transmitted to the host computer using a communication device. A reallocation request section
The host computer further includes:
A re-assignment request receiving unit that receives the assignment request transmitted by the wireless communication device using a communication device;
The address notification unit is a network address corresponding to a network address of a parent device related to the wireless communication device, and a network address other than the network address used by the wireless communication device is assigned to the wireless communication device. The wireless network system according to claim 2 or 3 , wherein the wireless network system is notified. The wireless communication device further includes:
The number of signal interference detections indicating the number of times the wakeup signal detection unit has detected a wakeup signal transmitted to another device based on the same multiplexing information as the own device is counted using the CPU, and the counted number of signal interference detections Including a signal interference detection frequency count unit that transmits to the host computer using a communication device,
The host computer further includes:
Based on the number of signal interference detections transmitted from the wireless communication device, an interference power consumption calculation unit that calculates interference power consumption by the wireless communication device by detecting a wakeup signal transmitted to another device using a CPU The wireless network system according to claim 2, further comprising:

Images