JP2010213164A - Wireless relay system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wireless relay system in which a slave unit receives a radio wave of the other slave unit to update line information, a master unit collects the updated line information from the slave unit in response to a request from the master unit, and the master unit can collect the latest line information at all the time. <P>SOLUTION: When a wireless master unit 1 receives a collection request of line information from a center device 5 or form a handy terminal 6 (S-1), the wireless master unit 1 returns a collection request response to a partner that has issued the collection request (S-2). Next, the wireless master unit 1 performs following collection sequences, namely, collection without relay 2 (S-4), collection with one stage of relay (S-5) and collection with two stages of relay (S-6) in this order and returns a collection completed slave unit identification code (ID) to the partner from which the request has been received in the sequence S-1 (S-7). Operation is explained as the collection sequences up to two stages of relays but the number of stages is not limited to two. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention is a wireless metering system that wirelessly performs meter readings such as power, gas, and water, or a wireless monitoring control system that performs monitoring and control such as state monitoring and abnormality monitoring, and cannot directly communicate with the wireless master unit. The slave unit relates to a wireless relay system that relays and communicates with other slave units.

Conventionally, in a wireless relay system, Patent Document 1 shown below obtains information for constructing a relay communication path by exchanging Hello packets.
Conventionally, in Patent Document 2 and Patent Document 3 shown below, a newly installed slave unit broadcasts, and nearby slave units that have received it respond at random timing. The handset installed in the system determines the route.

Conventionally, as information for determining a route, the electric field strength is used in Patent Documents 1 to 3 shown above and Patent Document 4 shown below.
Further, in Patent Document 5 shown below, the electric field strength value obtained by performing the communication operation for connection confirmation between two PHS terminal devices is associated with any numerical value of 15 levels to ensure transmission reliability. A technique for setting a route while selecting a route with a high numerical value is disclosed.

JP 2008-85583 A JP 2007-274068 A JP 2006-287468 A JP-A-11-168526 Japanese Patent No. 3308837 (paragraph 0047, Table 3)

  As in the above-mentioned Patent Document 1, in the method of confirming the electric field strength, which is information for determining a route with a Hello packet, regular Hello packet transmission and communication that passes the information to the entire network when the situation changes are normal communication. It is expected to be a hindrance. In particular, the influence is large in a 400 MHz band specific low-power wireless system or the like in which the communication speed is slow and the transmission suspension time is required.

  Further, in Patent Document 2 and Patent Document 3 described above, a newly installed child device broadcasts, and surrounding child devices that have received it respond at random timing. The machine decides the route, but if the response timing of surrounding slave units overlaps with one another, what can be received originally can not be received, and it is not known whether a really reliable route has been selected Problems arise.

  Furthermore, as information for selecting a communication path, the above-described Patent Document 1 to Patent Document 4 use the electric field strength, but the electric field strength and the communication success rate do not necessarily have a linear correspondence. Using as a judgment value as it is is not an optimal route selection.

  Further, in Patent Document 5 described above, a numerical value representing the certainty of transmission by associating an electric field strength value obtained by performing a communication operation for connection confirmation between two PHS terminal apparatuses with any numerical value of 15 levels. The route is set while selecting a route with a high numerical value, but the reliability of transmission is replaced with a numerical expression, but the numerical value means the field strength or the width of the field strength. Since the numerical value does not mean the communication success rate, it is not essentially different from the techniques disclosed in Patent Documents 1 to 4.

  Therefore, according to the present invention, the slave unit updates the line information by receiving the radio waves of other slave units, and the master unit collects the updated line information from the slave unit according to the request from the master unit. An object of the present invention is to provide a wireless relay system capable of collecting the line information.

The present invention has been made in view of such problems, and a plurality of wireless master devices connected to a center device via a communication line and a plurality of devices connected to a plurality of types of devices for meter reading and monitoring control are connected. A wireless communication system configured to read information on the device and / or control the device by communicating with at least one wireless slave device, wherein the wireless slave device is at least The wireless slave device that can communicate with one other wireless slave device and cannot directly communicate with the wireless slave device reads information of a device connected to the wireless slave device by relaying the wireless slave device and / or In a wireless communication system for controlling the device,
The wireless slave is
Communication means for performing transmission and reception of information for reading information of the device and / or controlling the device as a normal operation as a slave unit;
Command line information transmitting means for transmitting line information held by the wireless slave device itself according to a command from a terminal connected wirelessly;
Timer period line information transmitting means for automatically transmitting the line information in accordance with the timer period held by the wireless handset itself;
For reading and / or controlling radio waves for transmitting the line information by the command line information transmitting unit or the timer periodic line information transmitting unit, or information of the device during the normal operation, by the other wireless slave unit When the transmitted radio wave is received, a line information table for each slave unit that updates the identification code of the wireless slave unit and the field strength value of the adjacent slave unit and the reception elapsed timer value as the line information,
The wireless master unit is
Communication means for communicating with the wireless slave unit for reading information of the device and / or controlling the device as a normal operation as a base unit;
Line information requesting means for requesting transmission of line information held by the wireless slave device by designating a predetermined wireless slave device by an instruction from the center device or the wirelessly connected terminal;
Line information receiving means for receiving line information held by the wireless slave unit transmitted from the predetermined wireless slave unit;
The line information received by the line information receiving means is stored in the line information table and the line information table for each slave unit, the identification code of the wireless slave unit, the electric field strength value of the adjacent slave unit adjacent to the wireless slave unit, and the reception elapsed timer value. Line information management means for storing and managing;
It is characterized by providing.

  In addition, the wireless master device according to the present invention relays the line information held by each wireless slave device according to a command from the center device or the wirelessly connected terminal or in accordance with a timer cycle held by itself. And line information collecting means for collecting by no-communication and relay communication.

  In addition, the wireless master device according to the present invention extracts a reliability value defined by a communication success rate converted based on an electric field strength value in the line information from a reliability value table, in order of increasing reliability value, and When the reliability value is the same, the priority order is determined in ascending order of the reception elapsed timer value in the line information, and the order is stored in the route table, and the route information is stored, and connection is made with a slave unit that wants to communicate based on the route information. And

  According to the present invention, the line information possessed by the wireless slave unit is not limited to the dedicated line information radio wave but is used for normal communication (communication between the master unit and the slave unit, communication between the slave unit and the slave unit). For example, in a system with high communication frequency, there is no need to send out line information, and the load for maintaining the network is reduced.

  Also, collection of line information is performed in response to a request from the wireless master unit, so that information leakage due to a collision can be prevented. In addition, the wireless slave unit updates the line information in the wireless slave unit by receiving the radio waves of other wireless slave units by the collection operation, so the wireless master unit is the latest line information of the wireless slave unit. Can be collected.

  In addition, as information for selecting the communication path, the communication success rate converted from the electric field strength value is used as the reliability value, so that the optimum, that is, the actual path can be selected, and the latest reception elapsed timer value is set. By using it, the route is selected with priority on new information, so that the optimum route can be selected even when there is a change in the environment in communication.

1 is a diagram illustrating an overall configuration of a wireless relay system according to an embodiment of the present invention. It is a figure which shows the internal structure of the wireless main | base station which concerns on embodiment of this invention. It is a figure which shows the internal structure of the radio | wireless handset which concerns on embodiment of this invention. It is a flowchart explaining the process of line | wire information transmission in the radio | wireless handset which concerns on embodiment of this invention. It is a flowchart explaining the process of line | wire information preservation | save in the radio | wireless subunit | mobile_unit and radio | wireless main | base station which concern on embodiment of this invention. It is a figure which shows the structural example of the line information table which concerns on embodiment of this invention. It is a figure which shows the structural example of the channel | line information table according to subunit | mobile_unit concerning embodiment of this invention. It is a figure explaining the sequence of line information collection in the radio | wireless parent | base station which concerns on embodiment of this invention. It is a figure which shows the detailed sequence in the collection 1 without relay among the various collection sequences shown in FIG. It is a figure which shows the detailed sequence in the relayless collection 2 among the various collection sequences shown in FIG. It is a figure which shows the detailed sequence in 1 step | paragraph relay collection among the various collection sequences shown in FIG. FIG. 9 is a diagram showing a detailed sequence in two-stage relay collection among the various collection sequences shown in FIG. 8. FIG. 10 is a diagram illustrating a data format example of a multicast method used in the relayless collection 1 sequence illustrated in FIG. 9. It is a figure which shows the example of the line information request | requirement data format used by the relayless collection 2 sequence which concerns on embodiment of this invention. It is a figure which shows the example of the line information request | requirement data format used with the 1 step | paragraph relay collection sequence which concerns on embodiment of this invention. It is a figure which shows the example of the line information request | requirement data format used with the two-stage relay collection sequence which concerns on embodiment of this invention. It is a figure which shows the example of the line information response data format used by the relayless collection 1 and relayless collection 2 sequence which concerns on embodiment of this invention. It is a figure which shows the example of the line information response data format used with the 1 step | paragraph relay collection sequence which concerns on embodiment of this invention. It is a figure which shows the example of the line information response data format used with the two-stage relay collection sequence which concerns on embodiment of this invention. It is a figure explaining the subunit | mobile_unit search operation | movement of the 1-step relay which concerns on embodiment of this invention. It is a figure explaining the subunit | mobile_unit search operation | movement of the two-stage relay which concerns on embodiment of this invention. It is a figure which shows the accumulation probability graph in the Rayleigh fading environment which concerns on embodiment of this invention. It is a figure which shows the example of a reliability value table which concerns on embodiment of this invention. It is a figure explaining route search operation without relay concerning an embodiment of the present invention. It is a figure explaining 1 step | paragraph relay route search operation | movement which concerns on embodiment of this invention. It is a figure explaining the two-stage relay route search operation which concerns on embodiment of this invention. It is a figure which shows the example of a routing table which concerns on embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 is a diagram illustrating an overall configuration of a wireless relay system according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a wireless master device, 2-A to 2-D denote wireless slave devices that perform wireless communication with the wireless master device and other wireless slave devices, and 3-A to 3-D denote wireless slave devices 2-A. ˜2-D is a device such as a gas meter, a water meter, an electric meter, or various sensor devices connected to each other. The wireless master device 1 is connected to the center device 5 via a communication line 4 such as a telephone line or a dedicated line. The wireless master device 1 is at least communicable with the wireless slave devices 2-A to 2-C, and the wireless slave devices 2-A to 2-C are at least communicable with the wireless master device 1 and other than themselves. Communication with at least one other wireless slave unit is made possible. The wireless slave unit 2-D can communicate with the wireless slave units 2-A and 2-B on the assumption that the current position is fixed due to the arrangement. Then, the wireless slave unit 2-A or 2-B is relayed to be able to communicate with the wireless master unit 1. This arrangement is merely an example, and the wireless slave unit 2-D can be arranged at a position where it can communicate with the wireless slave units 2-B and 2-C. However, when the arrangement is determined, the system is constructed assuming that the position is fixed. In addition, the handy terminal 6 can freely change its position by the movement of the owner, and can communicate with the wireless slave units 2-A and 2-D in the illustrated example by operating a predetermined terminal at the destination. Although enabled, the owner of the handy terminal 6 moves to be able to communicate with any one of the wireless master device 1 and the wireless slave devices 2-A to 2-D, and the wireless master device that can communicate with it. 1 and the wireless slave units 2-A to 2-D can be given predetermined instructions.

  FIG. 2 is a diagram showing an internal configuration of the wireless master device according to the embodiment of the present invention. In FIG. 2, 11 is an antenna for communicating with the radio slave units 2-A to 2-C, 12 is a radio RF unit, 13 is a control unit for controlling the radio unit operation, and 14 is a radio slave unit 2-A to 2 -Line information collected from -D, a first information storage unit for holding route information constructed based on the line information, 15 is a second information storage unit for holding its own ID, and 16 is for measuring time A timer 17 is an interface unit (I / F unit) for connecting to the center device 5 and the handy terminal 6.

  FIG. 3 is a diagram showing an internal configuration of the wireless slave device according to the embodiment of the present invention. In FIG. 3, 21 is an antenna for communicating with the wireless master device 1 and other wireless slave devices, 22 is a wireless RF unit, 23 is a control unit for controlling the operation of the wireless device, and 24 is a parent device ID which is communication partner information. A first information storage unit for holding a device connected to the device, for example, a meter reading device ID, a meter reading result from the meter reading device, relay transfer presence / absence information, and the like. An information storage unit, 26 is a timer for measuring time, 27 is an interface unit (I / F unit) for connecting to devices such as the meter-reading device, and 28 is a switch for performing various operations.

FIG. 4 is a flowchart for explaining line information transmission processing in the wireless slave device according to the embodiment of the present invention. In FIG. 4, F is added to the head of the processing step.
Upon receiving an instruction (described later) for transmitting line information (F-1), the wireless slave units 2-A to 2-D wirelessly transmit the line information stored in the first information storage unit 24 ( F-2), the line information transmission operation is terminated. The line information transmission instruction described above is performed in each case, for example, by wireless reception by an instruction from the handy terminal 6, an instruction by operating the switch 28, or an instruction by time-up of the timer 26 held therein. There is. This is because when the wireless slave units 2-A to 2-D are installed in the wireless relay system according to the present invention, the line information is forcibly transmitted by the case of wireless reception by an instruction from the handy terminal 6 or the operation of the switch 28. This is to enable the use of a case in which the line information is periodically transmitted due to the time-up of the timer 26 in the wireless slave unit.

FIG. 5 is a flowchart for explaining processing for storing line information of the wireless slave device and the wireless master device according to the embodiment of the present invention. In FIG. 5, F is added to the head of the processing step.
The wireless slave units 2-A to 2-D and the wireless master unit 1 are normally in a wireless standby state (F-3). When a wireless radio wave is detected (F-4), the electric field strength of the wireless radio wave is measured. While receiving wirelessly (F-5). The electric field strength may be measured only once or a plurality of times. It is checked whether or not the destination of the received data is its own ID (F-6). If it is its own ID, it is data to be processed, and the routine shifts to a normal processing routine (F-7). If the destination of the received data is not its own ID, it is checked whether the ID of the transmitted child device already exists in the line information table (described later) in the first information storage unit 24 (F -8), if present, overwrite the field strength value and the reception elapsed timer value = 0 in the position (F-9), and if not, in the line information table (described later), the source ID and the above The field strength value measured in the processing step F-5 and the timer value = 0 are added (F-10).

  Here, a table regarding the line information stored and transmitted by the wireless slave units 2-A to 2-D and a table regarding the line information stored by the wireless base unit 1 will be described. FIG. 6 is a diagram showing a configuration example of a line information table according to the embodiment of the present invention. At the time of starting up the system, the wireless master device 1 performs line information collection processing for storing information of wireless slave devices with which the wireless master device 1 can directly communicate, and stores them in the line information table in the order of reception. Therefore, the line information table has an electric field strength value and a reception elapsed timer value in the table in the order in which the line information is received and for each identification code (ID) of the target slave unit. As for the electric field strength value, as described in the processing step F-5 above, the measured value is stored for a single measurement, and the median electric field strength is stored for a plurality of measurements. You may make it preserve | save an electric field strength average value instead of the electric field strength median value.

  From the above description, the operations of holding the line information in the wireless slave unit and the wireless master unit and transmitting the line information in the wireless slave unit according to the embodiment of the present invention will become clear. Note that the wireless master unit communicates with the wireless slave unit as a normal operation after the line information is stored in the first information storage unit 14 described above, and reads information on devices connected to the wireless slave unit and / or It controls equipment. The center device gives an instruction (command) to the wireless master device, and causes the device connected to the wireless slave device to read information and / or control the device.

  Next, the operation of collecting line information in the wireless master device according to the embodiment of the present invention will be described with reference to FIGS. In the wireless relay system of the present invention, the wireless master device 1 starts collecting line information upon receiving a line information collection instruction (described later). Here, the instruction for collecting the line information includes a case where the instruction is received from the center device 5, a case where the instruction is received from the handy terminal 6, and a case where the instruction is received due to the time-up of the timer 16 in the wireless master unit 1. .

  8 to 12 are diagrams for explaining a sequence of collecting line information in the wireless master device according to the embodiment of the present invention. In FIG. 8 to FIG. 12, S is added to the head of the sequence. FIG. 8 shows a sequence example when receiving an instruction from the center device 5 or receiving an instruction from the handy terminal 6.

  Upon receiving a line information collection request from the center device 5 or the handy terminal 6 (S-1), the wireless master device 1 returns a collection request response to the other party that issued the collection request (S-2). Next, the wireless master device 1 performs the following various collection sequences, ie, relayless collection 1 (S-3), relayless collection 2 (S-4), one-stage relay collection (S-5), two-stage relay collection ( S-6) is performed, and the slave unit identification code (ID) that has been collected is returned to the partner that received the request in sequence S-1 (S-7). In the present embodiment, the collection sequence up to two-stage relay is described, but the number of stages is not limited to two.

  Next, FIG. 9 is a diagram showing a detailed sequence of relayless collection 1 in sequence S-3 among the various collection sequences shown in FIG. The wireless master device 1 has a slave device ID with line information stored in the first information storage unit 14 and a slave device ID that has been instructed for collection in the collection request message from the center device 5 or the handy terminal 6. Are placed in a wireless message, and a line information request is transmitted by the multicast method (S-3-1). FIG. 13 is a diagram showing a data format example of the multicast method used in the relayless collection 1 sequence shown in FIG.

  The slave unit having its own identification code (ID) in the multicast format data format shown in FIG. 13 is checked for which number is designated, and the line information is returned as a response at the response timing according to the order ( S-3-2, S-3-3, S-3-4). FIG. 15A is a diagram showing a line information response data format example used in the relayless collection 1 sequence according to the embodiment of the present invention. In FIG. 9, for example, the response timing is as follows, starting from the end of transmission of the collection request message by the multicast method, with the guard time t sec and the slot interval T sec.

First designated slave unit: t sec
Second designated slave: (t + T) sec
Nth specified child device: t + T × (N−1) sec
The wireless master device 1 that has received the channel information from the wireless slave device whose response order is specified in the multicast format is stored in the slave-specific channel information table in the first information storage unit 14 under the control of the control unit 13. Write the collected contents. FIG. 7 is a diagram showing a configuration example of the line information table for each slave unit according to the embodiment of the present invention. At the time of writing to the table, if the wireless slave unit information already exists, it is overwritten, and if the wireless slave unit information does not exist, it is newly added (see the flow of FIG. 5). Thereby, the wireless master device 1 can store and manage the line information. The line information table for each slave unit shown in FIG. 7 corresponds to the wireless slave unit ID, the line information stored in the wireless slave unit, that is, the adjacent slave unit ID number and field strength value that the wireless slave unit can receive. The reception elapsed timer value is stored in a table.

  Next, FIG. 10 is a diagram illustrating a detailed sequence of the relayless collection 2 of the sequence S-4 among the various collection sequences illustrated in FIG. The wireless master device 1 stores the slave device ID having the line information stored in the first information storage unit 14 and the slave device ID that has been instructed for collection in the collection request message from the center device 5 or the handy terminal 6. A line information request is transmitted to the slave unit that could not be collected by the relayless collection 1 of sequence S-3 shown in FIG. 9 (S-4-1). FIG. 14A is a diagram showing an example of a line information request data format used in the relayless collection 2 sequence according to the embodiment of the present invention. The wireless slave device specified by the partner identification code (ID) in the line information request data format transmits a line information response (S-4-2). FIG. 15A is a diagram showing an example of a line information response data format used in the relayless collection 2 sequence according to the embodiment of the present invention. The wireless master device 1 that has received the line information response data writes the collected contents in the handset-specific line information table (see FIG. 7) in the first information storage unit 14. At the time of writing to the table, if the wireless slave unit information already exists, it is overwritten, and if the wireless slave unit information does not exist, it is newly added (see the flow of FIG. 5). The wireless master device 1 performs the above operation in the slave device identification code (ID) having the line information stored in the first information storage unit 14 and the collection request message from the center device 5 or the handy terminal 6. For the child device IDs for which collection has been instructed, it is repeated for all the child devices that could not be collected in the relayless collection 1 of sequence S-3.

  Next, FIG. 11 is a diagram showing a detailed sequence of the one-stage relay collection of sequence S-5 among the various collection sequences shown in FIG. The wireless master device 1 stores the slave device ID having the line information stored in the first information storage unit 14 and the slave device ID that has been instructed for collection in the collection request message from the center device 5 or the handy terminal 6. The line information is collected by one-stage relay for the slave unit 1 that cannot be collected by the relayless collection 1 of the sequence S-3 shown in FIG. 9 and the relayless collection 2 of the sequence S-4 shown in FIG. Do. The wireless master device 1 searches for the slave device ID 2 to be collected, that is, the target slave device ID 2 of the first-stage relay destination, from the adjacent slave unit IDs in the line information table for each slave device shown in FIG. The relayless child device ID1 that brought the line information of the target child device ID2 is taken out. If the extracted relayless child device ID1 is in the line information table (see FIG. 6) held by the wireless master device 1, the child device of the extracted relayless child device ID1 is relayed (used for relaying) and 1 Collect the line information of the target slave unit ID2 at the stage relay destination.

  FIG. 16 is a diagram for explaining the one-stage relay slave unit search operation according to the embodiment of the present invention. In accordance with the description of the one-stage relay slave unit search operation shown in FIG. 16 and the above-described explanation when the line information collection operation is performed by the one-stage relay, the slave unit used for relaying is selected from the line information table shown in FIG. If found, the wireless master device 1 transmits a line information request to the slave device (relay slave device) in FIG. 11 (S-5-1). FIG. 14B is a diagram showing an example of a line information request data format used in the one-stage relay collection sequence according to the embodiment of the present invention. In FIG. 11, when the above-described line information request data transmitted from the wireless slave unit 1 (relay slave unit) designated for relay is received, the wireless slave unit 1 (relay slave unit) is a relay, so the “relay information” shown in FIG. "Relay stage" in "" is rewritten from 0 to 1, and the line information request data is transferred (S-5-2). When the handset specified as the destination, wireless handset 2 in FIG. 11, receives the line information request data in sequence S-5-2, the handset transmits a line information response (S-5-3). . FIG. 15B is a diagram showing an example of a line information response data format used in the one-stage relay collection sequence according to the embodiment of the present invention. When the wireless handset 1 (relay handset) designated for relay receives the above-mentioned line information response data transmitted, the wireless handset 1 (relay handset) is a relay, so in the “relay information” shown in FIG. 15B. The “relay stage” is rewritten from 0 to 1, and the line information response data is transferred (S-5-4). The wireless master device 1 that has received the line information response data in this way writes the collected contents in the individual device-specific line information table (see FIG. 7) in the first information storage unit 14. At the time of writing to the table, if the wireless slave unit information already exists, it is overwritten, and if the wireless slave unit information does not exist, it is newly added (see the flow of FIG. 5). The wireless master device 1 performs the above operation in response to a collection instruction in the slave device ID having the line information stored in the first information storage unit 14 and the collection request message from the center device 5 or the handy terminal 6. With respect to the slave unit IDs, all of the slave units that could not be collected in the relayless collection 1 of the sequence S-3 and the relayless collection 2 of the sequence S-4 are repeatedly performed to complete the one-stage relay collection.

  Next, FIG. 12 is a diagram showing a detailed sequence of the two-stage relay collection of sequence S-6 among the various collection sequences shown in FIG. The wireless master device 1 stores the slave device ID having the line information stored in the first information storage unit 14 and the slave device ID that has been instructed for collection in the collection request message from the center device 5 or the handy terminal 6. 9 can be collected by the relayless collection 1 of the sequence S-3 shown in FIG. 9, the relayless collection 2 of the sequence S-4 shown in FIG. 10, and the one-stage relay collection of the sequence S-5 shown in FIG. Line information is collected by two-stage relay for the slave units that did not exist. The wireless master device 1 searches for the slave device to be collected, that is, the target slave device ID 3 of the second relay destination from the adjacent slave device IDs in the line information table for each slave device shown in FIG. The wireless slave device ID2 of the first relay destination that brought the line information of the target slave device ID3 is taken out. Further, the taken out slave unit ID2 of the first stage relay destination is searched from the neighboring slave unit IDs in the channel information table for each slave unit held by the wireless master unit 1, and at that time, the line information of the slave unit ID2 of the first stage relay destination is provided. Take out the wireless slave unit ID1 without relay. If the extracted relayless slave unit ID1 is in the line information table (see FIG. 6) held by the wireless master unit 1, the slave unit ID1 and the slave ID2 of the first relay destination Each slave unit is relayed (used for relaying), and the line information of the target slave unit ID3 of the second relay destination is collected.

  FIG. 17 is a diagram for explaining a two-stage relay slave unit search operation according to the embodiment of the present invention. In accordance with the description of the two-stage relay slave unit search operation shown in FIG. 17 and the above-described explanation when the line information collection operation is performed with the two-stage relay, it is used for the first-stage relay from the line information table shown in FIG. When the wireless slave device 1 (one relay slave device) is found, the wireless master device 1 transmits a line information request in FIG. 12 (S-6-1). FIG. 14C is a diagram showing an example of a line information request data format used in the two-stage relay collection sequence according to the embodiment of the present invention. In FIG. 12, when the above-mentioned line information request data transmitted from the wireless slave device 1 (one relay slave device) designated as the first-stage relay is received, the wireless slave device 1 (one relay slave device) is a relay. The “relay stage” in the “relay information” shown in 14C is rewritten from 0 to 1, and the line information request data is transferred (S-6-2). When the wireless handset 2 (2 relay handset) designated as the second-stage relay receives the transferred line information request data, the wireless handset 2 (2 relay handset) is a relay, and therefore “ The line information request data transferred by rewriting the “relay stage” in the “relay information” from 1 to 2 is further transferred (S-6-3). When the slave unit specified as the destination, wireless slave unit 3 in FIG. 12, receives the line information request data in sequence S-6-3, the corresponding slave unit (target slave unit of the second stage relay destination) Is sent (S-6-4). At this time, the received first-stage relay and second-stage relay identification codes (ID) are exchanged to respond. FIG. 15C is a diagram showing an example of a line information response data format used in the two-stage relay collection sequence according to the embodiment of the present invention. When the wireless slave unit 2 (one repeater slave unit) designated as the first-stage relay receives the transmitted line information response data, the wireless slave unit 2 (one repeater slave unit) is a relay, so that “ The above-mentioned line information response data transmitted by rewriting “relay stage” in “relay information” from 0 to 1 is transferred (S-6-5). Next, when the above-mentioned line information response data transferred by the wireless slave device 1 (2 relay slave device) designated as the second-stage relay is received, the wireless slave device 1 (2 relay slave device) is a relay. The “relay stage” in the “relay information” shown in FIG. 4 is rewritten from 1 to 2, and the line information response data is further transferred (S-6-5). The wireless master device 1 that has received the line information response data in this way writes the collected contents in the individual device-specific line information table (see FIG. 7) in the first information storage unit 14. At the time of writing to the table, if the wireless slave unit information already exists, it is overwritten, and if the wireless slave unit information does not exist, it is newly added (see the flow of FIG. 5). The wireless master device 1 performs the above operation in the slave device identification code (ID) having the line information stored in the first information storage unit 14 and the collection request message from the center device 5 or the handy terminal 6. For the slave unit identification code (ID) for which collection was instructed, the slave unit that could not be collected by the relayless collection 1 of sequence S-3, the relayless collection 2 of sequence S-4, and the one-stage relay collection of sequence S-5 Repeat for all to complete the two-stage relay collection.

  In addition, after the collection is completed or in the middle of the collection, the wireless master device 1 stores a value stored in a table corresponding to the return and return in the channel information table for each slave device shown in FIG. For “information on slave unit 2” and “information on slave unit 1 adjacent to slave unit 2”, the data with the smaller reception elapsed timer value, that is, the new timer value data is rewritten, the same reliability value, and the same reception elapsed timer value. To.

From the description above, the operation of collecting line information in the wireless master device according to the embodiment of the present invention will become clear.
In the above description, the example in which the wireless master device 1 collects line information without being based on the route table has been described. From now on, the wireless master device 1 stores the reliability value table and the route in the first information storage unit 14. Another embodiment according to the present invention that holds tables and collects line information based on these tables will be described. That is,
First, generation of a confidence value table according to the present embodiment will be described with reference to FIGS. 18A and 18B. As will be described later, the reliability value defined in the present embodiment is a probability that a bit error will occur if the radio wave fluctuation environment that causes the electric field intensity value based on the electric field intensity value becomes a Rayleigh fading environment and becomes smaller than the reception limit. The bit error rate is determined as being, converted into a normal reception probability with a code that can be corrected by error control, and the probability of successful communication with the communication data length used in the vertical direction of communication with respect to the reception probability. That is, the communication success rate is obtained, converted into a numerical value obtained by multiplying the communication success rate by 100, and displayed. Thus, the reliability value table indicating the conversion from the electric field strength value to the communication success rate value is represented as shown in FIG. 18B, and for the purpose of confirming the connection between the two PHS terminal devices as in Patent Document 5 described above. Although the electric field strength value obtained by performing the communication operation is associated with any numerical value of 15 levels to represent the certainty of transmission, the reliability does not mean the communication success rate because the numerical value does not mean the communication success rate. It is very different.

  Here, the conversion from the electric field strength value to the communication success rate value will be described. The reception limit of the wireless master device 1 and the wireless slave devices 2-A to 2-D is set to −113 dBm from the performance of the wireless device, and the radio wave variation Is the Rayleigh fading environment, and the electric field strength value is the median electric field strength in the presence of radio wave fluctuation, and the cumulative probability graph is obtained, and the probability that the probability of receiving less than -113 dBm will cause a bit error, that is, Bit error rate (BER). FIG. 18A is a diagram showing a cumulative probability graph in a Rayleigh fading environment when the electric field strength is −90 dBm. The reason why the radio wave fluctuation environment to which the wireless relay system of the present invention is applied is a Rayleigh fading environment is that the wireless relay system of the present invention needs to assume a Rayleigh fading environment in consideration of multifading in non-line-of-sight communication. Because there is. From the graph shown in FIG. 18A, the bit error rate (BER) when the electric field intensity is −90 dBm is 0.348%.

  Next, assuming that the 2-bit correction function is used for BCH (31,16) code as error control, up to 2 bits can be corrected with respect to 31 bits of encoded data, so the probability that a 31-bit block will be normal Is as follows.

₃₁ C ₀ (BER) ⁰ (1−BER) ³¹ + ₃₁ C ₁ (BER) ¹ (1−BER) ³⁰ + ₃₁ C ₂ (BER) ² (1−BER) ²⁹
= 0.999823
Now, if communication of 31-bit blocks is a message with 32 downlink messages (request message to the wireless slave device) and 160 uplink messages (response message from the wireless slave device), the communication is communication. The probability of success, that is, the communication success probability is
0.999823 ³² * 0.999823 ¹⁶⁰ = 96.67%
It becomes. Similarly, the communication success probability when the field intensity is other than −90 dBm, that is, the reliability value is also obtained, and the reliability value table as shown in FIG. 18B is obtained. The trust values in the trust value table shown in FIG. 18B are values with a communication success rate of 100% set to “10000”. The confidence value for the above 96.67% is “9667”. Although the bit error rate and communication success rate columns are also provided in the reliability value table of FIG. 18B, these are intermediate data for obtaining the reliability value. There should be a field for electric field strength and a column for confidence value. Therefore, the reliability value table finally becomes a conversion table between the electric field strength value and the communication success rate value.

  Next, generation of a route table according to the present embodiment will be described with reference to FIGS. First, the route search operation according to the present embodiment will be described. FIG. 19 is a diagram illustrating a route search operation without relay according to the embodiment of the present invention. In FIG. 19, it is assumed that the wireless master device 1 communicates with the slave device 1 as a communication partner. In this case, the wireless master device 1 first checks whether the wireless slave device 1 can directly communicate. If there is a slave unit ID to be communicated in the line information table 31 (see also FIG. 6), the slave unit ID is written in the route table 35 as priority order 1. Further, the reliability value and the reception elapsed timer value, which are table-converted with reference to the reliability value table 33 based on the electric field strength value registered in the line information table 31 for the child device ID, are written in the route table 35. In this case, the confidence value is as follows.

Trust Value = Reliability Value Between Base Unit and Handset 1 FIG. 20 is a diagram illustrating a one-stage relay route search operation according to the embodiment of the present invention. In FIG. 19, a case has been described in which communication is performed without relay with the slave unit 1 as a communication partner, but here, the communication path is examined by performing one-stage relay and the path is stored. The procedure will be described with reference to FIG.
(1) The wireless master device 1 refers to the slave device-specific line information table 32 (see also FIG. 7) and searches for the adjacent slave device ID 2 in the slave device 1 to be communicated.
(2) Next, the wireless master device 1 confirms whether or not the adjacent slave device ID 2 is registered in the line information table 31 (see also FIG. 6) (there is no one-stage relay if it is not present).
(3) If there is in the line information table 31 (see FIG. 6), the electric field strength value between the parent device 1 and the child device 2 in the line information table 31 and the child device 2 and the child in the individual child device line information table 32 By referring to the reliability value table 33 based on the electric field strength value between the machines 1, the reliability value is calculated based on the following expression for the reliability value, and the temporary value is obtained as the reliability value of the route obtained by the one-stage relay. Saved in the route table 34. Along with this information, the information of the communication partner child device 1 as the destination information and the child device 2 as the relay child device (one relay child device) related to the one-stage relay is also stored in the temporary route table 34 as route information. To do. In this case, the confidence value is as follows.

Trust value = (trust value between base unit and handset 2 × trust value between handset 2 and handset 1) / 10000
(4) When saving to the route table 35, the data registered in the route table 35 is compared with the trust values in the temporary route table 34. Arrange them in ascending order of timer values. The reception elapsed timer value to be compared is
Received elapsed timer value = a large value of (received elapsed timer between the master unit and the slave unit 2) and (received elapsed timer between the slave unit 2 and the slave unit 1).
(5) Repeat the above steps (1) to (4) for the adjacent slave unit registered as the adjacent slave unit ID of the slave unit to be communicated. The priority order obtained as a result is registered under a ranking different from the priority order described in FIG. Of course, priority is given to route search by one-stage relay.

FIG. 21 is a diagram for explaining a two-stage relay route search operation according to the embodiment of the present invention. In FIG. 21, a case has been described in which communication is performed with a communication partner by performing one-stage relay, but here, a two-stage relay is performed to check a communication path and the path is stored. The procedure will be described with reference to FIG.
(1) The wireless master device 1 refers to the slave device-specific line information table 32 (see also FIG. 7) and searches for the adjacent slave device ID 3 in the slave device 1 to be communicated.
(2) Next, the wireless master device 1 searches the adjacent child device ID 2 in the adjacent child device ID 3 from the line information table 32 for each child device.
(3) Next, the wireless master device 1 confirms whether the adjacent slave device ID 2 is in the line information table 31 (see also FIG. 6) (if there is no, the two-stage relay is not performed).
(4) If there is in the line information table 31, the electric field strength value between the base unit 1 and the handset 2 in the line information table 31, and between the handset 2 and the handset 3 in the handset-specific line information table 32. Based on the electric field strength value and the electric field strength value between the handset 3 and the handset 1 in the handset-specific line information table 32, the trust value table 33 is referred to and based on the following formula for calculating the trust value. A trust value is calculated and stored in the temporary route table 34 as a route trust value obtained by two-stage relay. Along with this information, the communication partner slave unit 1 as the destination information involved in the two-stage relay, the slave unit 2 as the relay slave unit (1 relay slave unit), the child as the relay slave unit (2 relay slave unit) Information on the machine 3 is also stored in the temporary route table 34 as route information. In this case, the confidence value is as follows.

Trust value = (trust value between base unit and handset 2 × trust value between handset 2 and handset 3 × trust value between handset 3 and handset 1) / (10000 ² )
(5) When saving to the routing table 35, the data registered in the routing table 35 is compared with the confidence values in the temporary routing table 34. Arrange them in ascending order of timer values. The reception elapsed timer value to be compared is
Received elapsed timer value = (Elapsed timer between master unit and slave unit 2), (Received elapsed timer between slave unit 2 and slave unit 3), and (Receive elapsed timer between slave unit 3 and slave unit 1) Is the largest value.
(6) Repeat (2) to (5) above for the adjacent slave units registered in the adjacent slave unit ID3.
(7) The above (1) to (6) are repeated for the adjacent slave unit registered in the slave unit ID 1 to be communicated. The priority order obtained as a result is registered under a ranking different from the priority order described in FIG. Of course, priority is given to route search by two-stage relay.

  An example of the route table 35 obtained by performing the route search operation shown in FIGS. 19 to 21 is shown in FIG. In the example shown in FIG. 22, no relay, no relay, reception elapsed timer, and reliability value are stored in a table for the communication partner “00001”. Similarly, the slave unit has data in the table. In the present embodiment, the wireless master device 1 has the reliability value table 33 and the route table 35 in the first information storage unit 14, and the field strength value is used as information for the wireless master device 1 to select a communication route. By using the confidence value table 33 having the communication success rate converted from the confidence value as a confidence value, it is possible to select the optimum route, that is, the actual route, and by using the route table 35 having the latest reception elapsed timer value, Since the route is selected with priority given to new information, the optimum route can be selected even when the environment changes.

1 Wireless master unit 2-A, 2-B, 2-C, 2-D Wireless slave unit 3-A, 3-B, 3-C, 3-D Various meters or sensor devices 4 Communication line 5 Center device 6 Handy Terminal 11 Antenna 12 Wireless RF unit 13 Control unit 14 First information storage unit 15 Second information storage unit 16 Timer 17 Interface unit 21 Antenna 22 Wireless RF unit 23 Control unit 24 First information storage unit 25 Second information Storage unit 26 Timer 27 Interface unit 28 Switch 31 Line information table 32 Line information table for each slave unit 33 Trust value table 34 Temporary route table 35 Route table

Claims (6)

A wireless master device connected to the center apparatus via a communication line and a plurality of wireless slave devices to which a plurality of types of devices for meter reading and monitoring control are respectively connected. The wireless master device is at least one wireless slave device. A wireless communication system for reading information on the device and / or controlling the device by communicating with a wireless device, wherein the wireless slave device is capable of communicating with at least one other wireless slave device; In the wireless communication system in which the wireless slave device that cannot directly communicate with the wireless slave device performs information reading and / or control of the device connected to the wireless slave device by relaying the wireless slave device,
The wireless slave is
Communication means for performing transmission and reception of information for reading information of the device and / or controlling the device as a normal operation as a slave unit;
Command line information transmitting means for transmitting line information held by the wireless slave device itself according to a command from a terminal connected wirelessly;
Timer period line information transmitting means for automatically transmitting the line information in accordance with the timer period held by the wireless handset itself;
For reading and / or controlling radio waves for transmitting the line information by the command line information transmitting unit or the timer periodic line information transmitting unit, or information of the device during the normal operation, by the other wireless slave unit When the transmitted radio wave is received, a line information table for each slave unit that updates the identification code of the wireless slave unit and the field strength value of the adjacent slave unit and the reception elapsed timer value as the line information,
The wireless master unit is
Communication means for communicating with the wireless slave unit for reading information of the device and / or controlling the device as a normal operation as a base unit;
Line information requesting means for requesting transmission of line information held by the wireless slave device by designating a predetermined wireless slave device by an instruction from the center device or the wirelessly connected terminal;
Line information receiving means for receiving line information held by the wireless slave unit transmitted from the predetermined wireless slave unit;
The line information received by the line information receiving means is stored in the line information table and the line information table for each slave unit, the identification code of the wireless slave unit, the field strength value of the adjacent slave unit adjacent to the wireless slave unit, and the reception elapsed timer value. Line information management means for storing and managing;
A wireless relay system comprising: The wireless master unit performs relay-less communication and relay communication on the line information held by each wireless slave unit according to a command from the center device or the wirelessly connected terminal or in accordance with a timer cycle held by itself. Line information collection means to collect at
The wireless relay system according to claim 1, further comprising:   3. The wireless communication system according to claim 2, wherein the line information collecting means designates the wireless slave device by multicast when performing the relayless communication.   3. The wireless communication system according to claim 2, wherein the line information collecting means includes relay communication by at least one or more wireless slave units when performing the relay communication.   The wireless master unit extracts a trust value defined by a communication success rate converted based on an electric field strength value in the line information from a trust value table, and the trust values are the same in descending order of the trust values. In this case, the priority order is determined in ascending order of the reception elapsed timer value in the line information, stored in a route table, connected to a handset that wants to communicate based on the route information and the route information. The wireless relay system according to any one of 4 to 4.   The communication success rate is determined based on the electric field strength value as a probability that a probability of causing a bit error is a probability of being smaller than the reception limit as a Rayleigh fading environment in which the radio wave fluctuation environment that brings about the electric field strength value is obtained, This is defined as the probability of successful communication with the communication data length used in the vertical direction of communication with respect to the reception probability converted into a normal reception probability with a code that can be corrected by error control. The wireless relay system according to claim 5.