JP2012151554A - Communication path implementation method for radio communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a communication path implementation method for a radio communication system, capable of performing implementation work of a radio communication path between a master station and a plurality of sub-stations installed in a building easily at low cost.SOLUTION: Test communication is performed by setting a master station 2 and a plurality of sub-stations 1 disposed in an identical building 5 to successively become a transmission station. Communication results such as success or failure of reception and receiving sensitivity are displayed in a list (communication test result table) 6. Based on the list 6, to a communication defective station among the plurality of sub-stations 1 unable to perform direct mutual communication with the master station 2, another sub-station 1 performing good direct mutual communication with the communication defective station and with the master station 2 is selected to be a relay station, so that a communication path is implemented between the communication defective station and the master station 2 through the other sub-station 1. Further, when a suitable sub-station 1 does not exist as the relay station, measures such as decreasing communication speed, increasing communication power and adding a dedicated relay station 8 are taken.

Description

  The present invention relates to a communication path construction method for a wireless communication system configured by arranging a master station and a slave station in a building such as a building so that wireless communication can be performed.

  As a method of selecting a communication path capable of performing stable communication in a wireless communication system, in order to efficiently arrange a plurality of sensor terminals when building a wireless network in a wide place such as a substation, Japanese Patent Application Laid-Open No. 2004-133867 discloses a prior art that displays a connection state between sensor terminals. In this prior art, a plurality of sensor terminals having a wireless communication function, a received electric field strength measurement function, etc. are preliminarily installed in the monitoring target area to temporarily construct a wireless network, and the received electric field strength at the time of mutual communication between these sensor terminals After collecting the measurement data related to the communication success rate, a network configuration diagram showing the connection state between the sensor terminals is created, so that a multi-route wireless communication path can be grasped.

JP 2010-45701 A

  The above-described prior art is effective when constructing a complicated wireless network that requires a multi-route wireless communication path. However, a master station, a slave station, and a minimum necessary number of relay stations are installed in a building. When applied to a relatively simple wireless communication system arranged and arranged, there is a problem in that it is extremely disadvantageous in terms of cost. In other words, when the above-described conventional technology is applied to such a relatively simple wireless communication system, not only is it necessary to perform complicated work to find a suitable wireless communication path, but also the wireless communication between the slave station and the master station. Since a large number of relay stations for relaying communication must be installed, parts cost, installation cost, and maintenance / inspection cost increase, and the wireless communication system becomes undesirably expensive.

  The present invention has been made in view of the actual situation of the prior art as described above, and its purpose is to easily and easily construct a wireless communication path between a master station installed in a building and a plurality of slave stations. An object of the present invention is to provide a communication path construction method for a wireless communication system that can be performed at low cost.

  In order to achieve the above object, the present invention provides that at least one master station and a plurality of slave stations each having a wireless communication function are installed in the same building, and the state quantity in the building is set in the slave station. In a communication path construction method of a wireless communication system in which a sensor for measuring a signal is connected and a measurement value of the sensor is transmitted to the master station, the master station and one of the plurality of slave stations The test communication including the data indicating whether or not the reception state is appropriate by performing the test communication of transmitting from the station and receiving at the remaining stations a predetermined number of times at predetermined time intervals so that all the stations sequentially become transmitting stations. The result of the communication is displayed as a list, and based on the list, the communication failure station and the parent station for the communication failure station that cannot perform direct mutual communication with the parent station among the plurality of slave stations. Relay another slave station to improve direct intercommunication with Selected to, and so as to build a communication path that performs radio communication with the master station and the communication failure station via the another slave station.

  By displaying the test communication results in a list (for example, a matrix table) in this way, it is instantaneously determined whether or not wireless communication can be performed satisfactorily between the master station and each slave station and between slave stations. it can. In addition, referring to this list, a relay station that can establish wireless communication between the slave station and the master station for another slave station (communication defective station) that cannot perform direct mutual communication with the master station is different. You can easily select from the slave stations.

  Further, the communication path construction method of the wireless communication system according to the present invention reduces the communication speed or communication when there is no slave station suitable as a relay station for the communication failure station among the plurality of slave stations. After increasing the power, the test communication is performed again, and it is determined whether wireless communication between the poor communication station and the parent station can be established based on a list as a result of the new test communication. I did it. In this way, if the communication speed is reduced or the communication power is increased and the test communication is performed again, the reception sensitivity may be increased. Therefore, it is easy to find a communication path that enables wireless communication between the bad communication station and the master station. Become.

  If the communication path that can establish the wireless communication between the poor communication station and the master station is not found even if the test communication is performed again after reducing the communication speed or increasing the communication power. In this case, a dedicated relay station may be added, and wireless communication between the poor communication station and the master station may be established via the dedicated relay station.

  Further, in the communication path construction method of the wireless communication system according to the present invention, when performing the test communication, the humidity of each place where the plurality of slave stations is installed is transmitted to the slave station existing in the place. It is preferable to memorize. By doing so, it becomes possible to estimate whether or not the cause of the communication failure is humidity, so that measures can be easily taken.

  The present invention implements test communication by setting so that a master station and a plurality of slave stations arranged in the same building are sequentially transmitting stations, and the result of the test communication including data indicating the suitability of the reception state is obtained. Since it is displayed as a list, not only can you quickly determine whether wireless communication can be performed well between the master station and each slave station, or between slave stations, but direct mutual communication with the master station is also possible. A relay station that can establish wireless communication between the slave station and the master station can be easily selected from other slave stations for a slave station (communication failure station) that cannot be performed. Therefore, a communication path capable of stable wireless communication can be easily and inexpensively constructed, and a highly reliable and inexpensive wireless communication system can be easily realized.

It is a block diagram which shows schematic structure of the radio | wireless communications system in embodiment of this invention. It is a flowchart for demonstrating the communication path construction method in this embodiment. It is explanatory drawing which shows the example of arrangement | positioning in the building of the main | base station and a sub_station | mobile_unit in this embodiment. It is explanatory drawing which shows an example of the sequence of the test communication in this embodiment. It is explanatory drawing which shows the image which carried out the matrix display of an example of the result of the test communication in this embodiment. It is explanatory drawing which shows the example of arrangement | positioning in the building of a dedicated relay station in this embodiment.

  Embodiments of a communication path construction method for a wireless communication system according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram showing a schematic configuration of a wireless communication system in the present embodiment. The wireless communication system shown in the figure is composed of a master station 2 and a plurality of slave stations 1 installed in the same building, and the master station 2 and each slave station 1 all have a wireless communication function. ing. Each slave station 1 is for transmitting measured values of state quantities such as power consumption and water consumption in the building to the master station 2, and the master station 2 is in a state transmitted from each slave station 1. The amount can be accumulated and stored.

  First, the configuration of the slave station 1 will be described in detail. The slave station 1 is connected to a sensor that measures state quantities such as the amount of power consumption, the amount of water used, and the amount of gas used, and the slave station 1 is provided with a measurement data input unit for inputting measurement data of the sensor. ing. In FIG. 1, a meter 4 with pulse transmission for measuring the amount of water used is shown as the sensor, and the pulse data output from the meter 4 with pulse transmission is input as the measurement data input unit of the slave station 1. 1b is illustrated. In the slave station 1, in addition to a measurement data input unit (for example, a pulse input unit 1b), a temperature / humidity input unit 1a to which measurement data of ambient temperature / humidity is input, and a maintenance purpose capable of inputting / outputting various data An external interface 1c for detachably connecting the personal computer 3, a wireless processing unit 1e that enables wireless communication via the antenna 1g and detects received power at the time of signal reception, and measurement data ( For example, a control unit 1d that performs processing such as calculating a state quantity (for example, the amount of water used) based on a pulse) as an integrated value, and a storage unit 1f that stores calculation data of the integrated value and the like are provided. The storage unit 1f also stores signal data received via the antenna 1g, detection data of the received power, temperature / humidity data captured from the temperature / humidity input unit 1a, and the like. The control unit 1d also performs processing for storing various types of data in the storage unit 1f, processing for extracting the data from the storage unit 1f, transmitting the data from the wireless processing unit 1e, and outputting the data to the personal computer 3.

  The master station 2 is provided with a communication interface 2d for remotely connecting to a monitoring center (not shown) via a communication line. Further, since the master station 2 is not connected to the sensor, the master station 2 is not provided with a measurement data input unit such as the pulse input unit 1b. However, the other configurations of the master station 2 are almost the same as those of the slave station 1. is there. That is, in addition to the communication interface 2d, the master station 2 enables wireless communication via an antenna 2g and an external interface 2b for detachably connecting a maintenance personal computer 3 and reception at the time of signal reception. A wireless processing unit 2a that detects power; a storage unit 2e that stores signal data received via the antenna 2g, detection data of received power, and the like; a process that stores these data in the storage unit 2e; A control unit 2c that performs processing such as extraction from the storage unit 2e and transmission from the wireless processing unit 2d or output to the personal computer 3 and a temperature / humidity input unit (not shown) to which ambient temperature / humidity measurement data is input are provided. It has been.

  A personal computer 3 is connected to the external interfaces 1c and 2b of each slave station 1 and the master station 2 when necessary, and various settings (test start time and communication speed) when performing test communication to be described later using the personal computer 3 are performed. , Communication power setting, etc.) and reception results after test communication are performed.

  Next, a method of constructing a communication path between each slave station 1 and the master station 2 in a wireless communication system composed of the master station 2 and a plurality of slave stations 1 will be described with reference to the flowchart of FIG. .

  First, one master station 2 and a plurality of slave stations 1 are temporarily installed at various locations in the same building (step S1). However, the place where each slave station 1 is temporarily installed is in the vicinity of a sensor that measures state quantities such as power consumption, water usage, and gas usage. As shown in FIG. 3, in this embodiment, it is assumed that two master stations 2 and five slave stations 1 are temporarily installed on each floor in a three-story building 5. For convenience, the master station 2 is assigned a machine number of 0, and the five slave stations 1 are assigned machine numbers of 1 to 5, respectively, so that they can be distinguished. That is, FIG. 3 shows that the master station 2 of Unit 0 and the slave station 1 of Unit 5 are temporarily installed on the first floor in the building 5, and the slave station 1 of Unit 3 and the slave station 1 of Unit 4 are installed on the second floor. The figure shows a state where the first slave station 1 and the second slave station 1 are temporarily installed on the third floor.

  Next, the maintenance personal computer 3 is connected to the external interface 2b of the master station 2 to set the continuous test mode. Similarly, the maintenance personal computers 3 are connected to the external interfaces 1c of all the slave stations 1 from No. 1 to No. 5 to set the continuous test mode (step S2).

  Here, the continuous test mode refers to a test communication in which all stations sequentially transmit test communications in which one station out of one master station 2 and a plurality of slave stations 1 is received by the remaining stations. This mode is set to be a station and is executed a predetermined number of times at predetermined time intervals. As shown in FIG. 4, in this embodiment, first, test communication is performed using the master station 2 of Unit 0 as the transmission station, and after 10 minutes, test communication is performed using the slave station 1 of Unit 1 as the transmission station. After 10 minutes, test communication is performed with the slave station 1 of Unit 2 as the transmitting station. In the same manner, test communication is performed every 10 minutes with the slave stations 1 of No. 3, No. 4, No. 5, and No. 5 being sequentially set as transmitting stations. The reception state (reception availability and reception sensitivity) on the receiving station side in the test communication continuously performed in this way is stored in the storage units 1f and 2e of the receiving station. In FIG. 4, white circles indicate transmitting stations, and black circles indicate receiving stations. The receiving station determines whether reception is possible and calculates reception sensitivity. Further, the time interval of the test communication is not limited to 10 minutes and can be set arbitrarily.

  After a predetermined period (for example, one week) has elapsed after setting the continuous test mode in this way, the maintenance personal computer 3 is connected to the external interfaces 2b and 1c of the master station 2 and all the slave stations 1, and this personal computer 3 is used. The result of the test communication is acquired (step S3).

  The personal computer 3 displays the communication test result table 6 and the communication path diagram 7 as shown in FIG. 5 on the display 3a by summing up the communication results thus obtained. The communication test result table 6 is a matrix table showing a reception state for each combination of a transmitting station indicated in a row and a receiving station indicated in a column. In addition, FIG. 7 illustrates a communication path that enables wireless communication between the master station 2 and each slave station 1 and between the slave stations 1 by lines.

  The communication test result table 6 illustrated in FIG. 5 displays the communication results for three times. Each communication result indicates “O” or “X” indicating whether or not reception is possible in order from the top. Reception sensitivity and humidity at reception. The humidity data is data taken into the storage units 1f and 2e from the temperature / humidity input unit 1a of the slave station 1 and the temperature / humidity input unit (not shown) of the master station 2. Further, the number of test communications is not limited to three, and can be arbitrarily set.

  According to the communication test result table 6 illustrated in FIG. 5, it can be instantaneously determined that the master station 2 of the 0th unit and the slave station 1 of the 4th and 5th units can directly communicate with each other. Also, if Unit 2's slave station 1 is the transmitting side and Unit 4's slave station 1 is the receiving side, it is possible to communicate 2 times out of the 3 test communications, but not 1 time. judge. However, according to Table 6 of the communication test results, the humidity around Unit 4 at the receiving side was 68% and 72% when communication was possible, whereas it was 88% when communication was impossible. Therefore, high humidity can be considered as a cause of communication failure. Therefore, the reception state may be improved by changing the installation location of Unit 4 or taking measures against humidity.

  Further, according to the communication test result table 6 illustrated in FIG. 5, although the slave station 1 of Unit 3 and the slave station 1 of Unit 4 can communicate with each other, only extremely low reception sensitivity of −117 to −102 dBm is obtained. I understand that there is no. Therefore, a reception sensitivity equivalent to this can be used as a guideline for the lower limit level of the reception sensitivity that can be communicated at other sites.

  Further, according to the communication test result table 6 illustrated in FIG. 5, the slave stations 1 that can directly communicate with the master station 2 of the No. 0 unit are only the No. 4 and No. 5 units. Cannot be directly communicated with the master station 2, but this Unit 3 can directly communicate with the Unit 4, so if the Unit 4 is interposed, the Unit 3 can wirelessly communicate with the master station 2. Become. That is, the slave station 1 of Unit 3 is a poor communication station with respect to the master station 2, but if the slave station 1 of Unit 4 is used as a relay station, a communication path with the master station 2 can be established. . On the other hand, the slave station 1 of the first unit is in communication failure with all other stations both on the transmitting side and on the receiving side, and the slave station 1 of the second unit is not connected to all other stations on the transmitting side. And poor communication.

  These results found by performing the test communication are displayed as a communication path diagram 7 in the lower area of the communication test result table 6 in the display 3 a of the personal computer 3. If this communication path diagram 7 is seen, the slave station 1 of the 4th machine and the 5th machine can directly communicate with the master station 2, and if the slave station 1 of the 3rd machine also uses the slave station 1 of the 4th machine as a relay station, Although it is possible to wirelessly communicate with the master station 2, since the slave station 1 of the first unit and the slave station 1 of the second unit cannot communicate with the master station 2, these first and second slave stations 1 You can instantly know that you need extra measures.

  Thus, since the result of the test communication is displayed as the communication test result table 6 and the communication route diagram 7, the slave station 1 used as the relay station can be selected, so that the communication route capable of wireless communication with the master station 2 is possible. Is found (step S4).

  Next, it is determined whether or not all the slave stations 1 can wirelessly communicate with the master station 2 (step S5). If the determination in step S5 is “Yes”, the process ends. If the determination is “No”, that is, if there is a slave station 1 that disables wireless communication with the master station 2, the communication speed is set. Is set to a low speed (step S6).

  If it is determined in step S6 that the communication speed is not set to a low speed ("No"), the maintenance personal computer 3 is connected to the external interfaces 2b and 1c of the master station 2 and all the slave stations 1. Thus, the communication speed is set to a low speed (step S7). Thereafter, in order to perform the test communication after the communication speed is lowered, the process returns to step S2, and if the determination in step S5 is “Yes”, the process ends. That is, even if the slave station 1 disables wireless communication with the master station 2 as in the first and second machines described above, the reception sensitivity may be increased by slowing the communication speed. It becomes easy to find a communication path capable of wireless communication with the communication test result table 6 from the communication test result table 6.

  However, even if the communication speed is set to a low speed, if a communication path that enables stable wireless communication with the master station 2 cannot be found in some slave stations 1, the determination in step S6 is “Yes”. Then, the process proceeds to step S8. In this step S8, a dedicated relay station is temporarily installed at an appropriate location, and the slave station 1 that cannot communicate wirelessly with the master station 2 even if the communication speed is set to a low speed, It is to be able to communicate. After the dedicated relay station is temporarily installed in step S8, the process returns to step S2 to perform test communication, and then a suitable communication path is selected from the communication test result table 6 in step S4.

  In the example shown in FIG. 6, the dedicated relay station 8 is temporarily installed as the sixth machine in the middle of the route where communication is impossible. When the dedicated relay station 8 was not added, there was no communication path for stable wireless communication between the first and second child stations 1 and 2 in the building 5, so the dedicated relay station 8 was installed. As the location, an intermediate position between the first slave station 1 and the second slave station 1 is selected. If the dedicated relay station 8 is added in this way, it becomes easy to establish a communication path capable of stably performing wireless communication between the slave station 1 and the master station 2 of the first and second units. In addition, in the present embodiment, the number of dedicated relay stations 8 to be added can be minimized. The dedicated relay station 8 is not connected to a sensor, so that a measurement data input unit is not necessary. However, the basic configuration of the dedicated relay station 8 may be the same as that of the slave station 1.

  As described above, in the communication path construction method of the wireless communication system according to the present embodiment, the master station 2 and a plurality of (five) slave stations 1 arranged in the same building 5 are sequentially set as transmitting stations. In order to display test results such as reception availability and reception sensitivity as a list (communication test result table 6), and between the master station 2 and each slave station 1, and the slave station 1 It can be instantaneously determined whether or not wireless communication can be performed satisfactorily. In addition, a relay station that can establish wireless communication between the slave station 1 and the master station 2 is assigned to another slave station 1 with respect to the slave station 1 (communication defective station) that cannot directly communicate with the master station 2. It is also possible to easily select from among them. Therefore, a communication path capable of performing stable wireless communication can be easily and inexpensively constructed.

  In the present embodiment, when there is a slave station 1 that cannot perform wireless communication with the master station 2 in the initial test communication, the communication speed is decreased and the test communication is performed again. However, the communication speed is decreased. Instead, the communication power may be increased and the test communication may be performed again.

  Further, in the present embodiment, the case where the master station 2 and the five slave stations 1 are arranged on three floors in the same building 5 is described as an example, but the required number of slave stations 1 is Needless to say, it depends on the size of the building, the number of floors, the object to be measured, and the like.

1 Slave station 1a Temperature / humidity input unit 1b Pulse input unit (measurement data input unit)
1c external interface 1e wireless processing unit 1f storage unit 2 master station 2a wireless processing unit 2b external interface 2e storage unit 3 personal computer 4 meter with pulse transmission (sensor)
5 Building 6 Communication test result table (list)
7 Communication path 8 Dedicated relay station

Claims (4)

At least one master station and a plurality of slave stations each having a wireless communication function are installed in the same building, and a sensor for measuring a state quantity in the building is connected to the slave station to measure the sensor. In a communication path construction method of a wireless communication system in which a value is transmitted to the master station,
Test communication that is transmitted from one of the master station and one of the plurality of slave stations and received by the remaining stations, a predetermined number of times at predetermined time intervals so that all stations sequentially become transmitting stations. The test communication results including the data indicating whether the reception status is appropriate are displayed as a list, and based on this list, direct communication with the master station among the plurality of slave stations can be performed. If there is no communication failure station, a relay station is selected as another slave station that improves direct communication with the communication failure station and the master station, and the communication failure station and the master station are connected via the other slave station. A communication path construction method for a wireless communication system, characterized in that a communication path for performing wireless communication with a master station is constructed.   In the description of claim 1, when there is no suitable slave station as a relay station for the poor communication station among the plurality of slave stations, the communication speed is slowed down or the communication power is increased. The test communication is performed again, and it is determined whether or not wireless communication between the poor communication station and the master station can be established based on a list as a result of the new test communication. A communication path construction method for a wireless communication system.   3. If the communication path that can establish wireless communication between the poor communication station and the master station is not found even after performing the test communication again, a dedicated relay station is added and the dedicated relay station is A communication path construction method for a wireless communication system, characterized in that wireless communication is established between the poor communication station and the master station.   4. The method according to claim 1, wherein when performing the test communication, the humidity at each location where the plurality of slave stations are installed is stored in the slave station existing at the location. A communication path construction method for a wireless communication system, characterized in that the communication path is constructed.

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