JP2015166217A - Railroad facility monitoring system and data communication device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make communication possible at a fairly high probability in the case where a failure occurs in a communication device in any one of a plurality of signal controlling devices that are installed along a railroad wayside, and even when electromagnetic interference or an electromagnetic disturbance is generated along the wayside.SOLUTION: A railroad facility monitoring system includes a plurality of signal controlling devices 10, and a monitoring device 20 for monitoring an operational state of the signal controlling devices 10 at a remote location. The railroad facility monitoring system is provided with: main radio communication means which is directly or indirectly connected to the monitoring device 20 and capable of performing radio communication using a plurality of different frequency bands; secondary radio communication means which is directly or indirectly connected to the signal controlling devices 10 and capable of performing radio communication using a plurality of frequency bands; and a repeater 31 which has a function for transferring data received by the radio communication using the plurality of frequency bands. In the railroad facility monitoring system, the main radio communication means, the secondary radio communication means, and the repeater 31 are arranged at an interval equal to or less than a half of a radio communication possible distance.

Description

  The present invention relates to a monitoring system for monitoring the state of a plurality of electrical devices arranged at distant positions and a wireless data communication device used therefor, and particularly to a railway facility monitoring system and a data communication device. It relates to effective technology.

  In the railway business, in order to carry out safe railway operations, many railroad crossing breakers, traffic lights, and other devices along the railway line and control devices such as railroad crossing control devices that control those devices (hereinafter referred to as signal control devices). ) Is arranged. Conventionally, abnormalities in signal control equipment along railroads have been detected visually by monitoring systems and drivers using analog lines with a very narrow communication band. When abnormalities are detected, the monitoring system and command room The maintenance department reports to the maintenance department about the occurrence of an abnormality, and the person in charge rushes to the site to take measures against the failure.

  Conventionally, some remote monitoring to acquire the status of these devices via a wired analog line has also been implemented, but the analog line has a small amount of data transmission and detailed data cannot be obtained. The operation records necessary for the maintenance management of the signal control device are confirmed by the person in charge going to the site and reading the data directly from the local device operation recording device. As described above, since monitoring and data collection of conventional signal control equipment for railways requires manpower and time, it is possible to remotely monitor and control the state of the signal control equipment, and to control the signal control equipment without going to the site. There is a demand for a system that can acquire an operation record and analyze the cause of an abnormality.

JP 2002-012150 A JP 2013-042344 A Japanese Patent No. 5224871 JP2013-085099A

The present inventors have studied a communication method between a signal control device and a device for monitoring the signal control device in a railway facility monitoring system. As a result, in the wired system, when a repeater breaks down, communication with the signal control device connected to the destination wire becomes impossible. Reached. In addition, a large-capacity communication network such as an optical line is installed along the railway line, and the signal control device and the monitoring device are connected to the optical line to control the equipment for checking the operation status, detecting anomalies, and maintaining the signal equipment Although it is conceivable, in the case of an optical line, the cost of laying the optical cable is enormous, which is not realistic.
In consideration of the inability to communicate due to disconnection, a technique for connecting a plurality of fixed stations installed along a predetermined route with a plurality of wired networks (Patent Document 1) has been proposed. In addition to the increase in cost, in the case of a wired network, it is expected that a plurality of lines are often unable to communicate at the same time if a fire occurs on the extended line even if they are multiplexed.

  Therefore, the present inventors paid attention to a wireless communication system. There are methods of using a wireless LAN such as a cellular phone or WiFi as a wireless communication method, but the former has a communication cost and the latter has a problem of radio wave interference. Particularly in urban areas, it is easy to cause interference with radio waves emitted from wireless LAN relay devices installed by existing communication companies. Wireless communication systems include wireless PAN (short-range wireless) represented by Bluetooth (registered trademark) and UWB (Ultra Wide Band) capable of large-capacity communication. There is a problem that is short.

By the way, as an invention for transmitting data using wireless communication, for example, a mobile station moving along a predetermined route, a plurality of fixed fixed stations installed along the route, and control / control of these communication There is an invention relating to a wireless communication network system that includes a control station that performs management and performs communication by a time division multiple access method (Patent Document 2).
Note that in the wireless communication network system such as Patent Document 2, a propagation network that relays information while sequentially performing wireless communication between adjacent wireless devices adjacent to each other is configured. When used in a tunnel, the gap between the train body and the tunnel is reduced, and when radio waves propagate through the gap, it is attenuated and a communication failure occurs between the radio along the line. There is a risk of being disconnected at a point.

Therefore, the invention of Patent Document 2 is arranged such that mobile radio devices are arranged at the front and rear portions of the mobile body so that they can communicate with each other, and when the mobile body exists between fixed radio devices capable of wireless communication with each other, By adopting a configuration in which information transmission between fixed wireless devices can be relayed by the two mobile wireless devices mounted on a mobile body, the above-described problems are avoided.
However, the wireless communication disclosed in Patent Document 2 has a problem in that communication cannot be performed when a failure occurs in any fixed wireless device.

In addition, in a remote monitoring system that collects measurement data from a plurality of measuring devices using relay-type wireless communication, an alternative communication path is set in advance when there is an incommunicable device in the middle of the communication path. An invention has also been proposed (Patent Document 3).
However, although the invention of Patent Document 3 is effective when a failure occurs in any of the devices, there is a problem that it cannot be handled when communication is disabled due to radio wave interference or radio wave interference. is there. In addition, it may be possible to avoid inability to communicate by preparing alternative communication paths corresponding to the devices at all installation locations, but doing so makes the system redundant and causes a significant increase in cost. End up.

  Furthermore, in a general wireless communication network system, it is possible to predict to some extent places where communication is disabled due to radio wave interference or radio wave interference. Setting a detour communication route in such a place will suppress an increase in cost. be able to. However, in the railway communication network system to which the present invention is supposed to be applied, the occurrence of breakdowns and accidents, for example, the generation of electromagnetic noise accompanying the occurrence of sparks from pantographs and high-voltage lines, etc. It is difficult to predict when and where this occurs, so it is difficult to set up detour communication routes, and trying to set detour communication routes in all locations has a problem inherent to railways that causes a significant increase in costs. .

The present invention has been made to solve the above-described problems. When a wireless communication method is adopted, a failure occurs in a communication device in any of a plurality of signal control devices installed along a railway line. An object of the present invention is to provide a railroad equipment monitoring system capable of performing communication with a fairly high probability even when radio wave interference or radio wave interference occurs along a railway line, and a data communication apparatus suitable for use in the system.
In addition, the invention (Patent Document 4) relating to a wireless communication system in which data is transmitted using a wireless device capable of wireless communication in two frequency bands of 2.4 GHz band and 955 MHz band has been proposed. It became clear by the inventors' investigation after the development of the present invention. However, the invention described in Patent Document 4 is a technology that usually performs communication in one of the frequency bands, and switches to another frequency band when the communication quality of one frequency band decreases. . In addition, when switching frequency bands, a request is made from one device to the other device, and the frequency band is switched after receiving a permission response, so communication in the frequency band in use is completely blocked. There is a problem that switching cannot be performed.

In order to solve the above problems, the first invention according to the present application is:
A railway facility monitoring system comprising one or more signal control devices arranged along a railway line, and a monitoring device that remotely monitors the operation state of these signal control devices,
A main wireless communication means connected directly or indirectly to the monitoring device and capable of wireless communication using different frequency bands;
Subordinate radio communication means connected directly or indirectly to the signal control device and capable of radio communication using the plurality of frequency bands;
Relay means having a function of transferring data received by wireless communication using the plurality of frequency bands,
The main radio communication unit, the subordinate radio communication unit, and the relay unit are arranged along a railway line at a distance of one half or less of a communicable distance by the radio communication. did.

The second invention according to the present application is
In a railway facility monitoring system comprising one or more signal control devices arranged along a railway line and a monitoring device that remotely monitors the operation state of these signal control devices, the signal control device Alternatively, in a data communication device that performs communication by being directly or indirectly connected to the monitoring device,
Wireless communication using all or any one of a plurality of different frequency bands is configured to be possible.

According to the first aspect of the invention, the wireless communication means and the relay means are arranged along the railway line at a distance of half or less of the communicable distance. Even if a failure occurs in the wireless communication means, it is possible to send data to the monitoring device by communicating with the wireless communication means of the next signal control device by skipping the signal control device in which the wireless communication means has failed. it can.
In addition, according to the first and second inventions, the wireless communication means connected to the monitoring device and the signal control device can perform wireless communication using a plurality of frequency bands, respectively. Even when radio wave interference or radio wave interference occurs on the way, it is rare that radio wave interference or radio wave interference occurs in all of a plurality of frequency bands, so communication can be performed with a very high probability.

Here, preferably, the wireless communication unit or the data communication device has a function of determining a communication state, and executes wireless communication in all frequency bands when all wireless communication in the plurality of frequency bands is possible. If the wireless communication using any one of the plurality of frequency bands is impossible, the data is transmitted by wireless communication using another frequency band capable of wireless communication. Configure as follows.
When all wireless communication in multiple frequency bands is possible, wireless communication in all frequency bands is executed and data is transmitted, so that the monitoring device collects the operating status of many signal control devices in a short cycle. This makes it possible to monitor with high accuracy.

Desirably, the wireless communication means or the data communication device is configured to transmit the data subjected to the degeneration processing when wireless communication using any one of the frequency bands is impossible.
As a result, when wireless communication using one of the frequency bands is impossible, the data subjected to degeneration processing is transmitted, so the amount of information necessary for monitoring is reduced, but the operating state of the signal control device can be completely understood. It is possible to avoid the situation of disappearance.

Further, preferably, the data to be transmitted is given a priority according to its type, and the degeneration process is a process that does not target the data with a low priority.
With this configuration, when wireless communication using any one of the frequency bands is impossible, data with low priority is not targeted for transmission, so the amount of information necessary for detailed monitoring is reduced, but the minimum Information necessary for the limited monitoring can be obtained, and it is possible to avoid a situation in which the operating state of the signal control device cannot be grasped in real time.

  According to the present invention, when a wireless communication system is adopted, a communication device fails in any of a plurality of signal control devices installed along a railway line, or radio wave interference or radio wave interference occurs along the line. Even if this occurs, there is an effect that it is possible to realize a monitoring system and a data communication apparatus that can communicate with a fairly high probability.

It is the schematic which shows one Embodiment of the railway equipment monitoring system which concerns on this invention. It is a block diagram which shows the structural example of the signal control apparatus monitoring server in the equipment monitoring system for railways of embodiment. It is a block diagram which shows the structural example of the ZigBee subunit | mobile_unit (henceforth a ZigBee subunit | mobile_unit) in the railway equipment monitoring system of embodiment. It is a block diagram which shows the structural example of the repeater in the railway equipment monitoring system of embodiment. It is a block diagram which shows the structural example of ZigBee main | base station (henceforth a ZigBee main | base station) in the railway equipment monitoring system of embodiment. It is a figure which shows the structural example of the data buffer in a ZigBee subunit | mobile_unit. It is a flowchart which shows an example of the procedure of the data transmission process in a ZigBee subunit | mobile_unit. It is a flowchart which shows an example of the procedure of the communication recovery process in a ZigBee subunit | mobile_unit. It is a flowchart which shows an example of the procedure of the control information transmission process to the signal controller in a signal control equipment monitoring server. It is a block diagram of the present signal control equipment monitoring system which collects data using an analog line. It is a figure which shows the structural example of the signal control apparatus monitoring system to which the ZigBee communication apparatus of embodiment of this invention is applied instead of the analog line in the present system. It is a figure which shows the other structural example of the signal control apparatus monitoring system which applied the ZigBee communication apparatus instead of the analog line.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a railway facility monitoring system and a data communication apparatus used therefor according to the present invention will be described with reference to the drawings.
The railway facility monitoring system of the present embodiment monitors, for example, the signal controllers 10 of a plurality of level crossing barriers arranged along a railway line as shown in FIG. IEEE. Zigbee slave devices 11 each having a function of wireless communication (hereinafter referred to as ZigBee communication) in accordance with the 802.15.4 standard (ZigBee communication standard) are provided.

A ZigBee master unit 21 capable of ZigBee communication is connected to the signal control device monitoring server 20 arranged in the command room or the like via a LAN 22 or the like. A ZigBee repeater 31 is provided between the ZigBee master unit 21 and the ZigBee slave unit 11, between the ZigBee slave units 11 at intermediate points between devices that are relatively distant from each other, and at the entrance / exit of a tunnel having a predetermined length or more. Are arranged respectively.
The signal controller 10 has a function of controlling a signal device such as a railroad crossing breaker and an alarm device (speaker, warning light), as well as a sensor (such as a position detector of a blocking bar) provided in the signal device or a fault. Signals from the object detection device and the emergency button switch are input, and a recording device for recording the operation state of these signals is provided.

In addition to the information recorded in the recording device, the ZigBee slave 11 in the present embodiment has a function of reading signals from sensors and detectors provided in the signal controller 10 and transmitting them as information. . Further, the ZigBee slave unit 11 receives data transmitted from the adjacent ZigBee slave unit 11 and the repeater 31, and together with the data from the signal controller 10 connected thereto, A function for transferring to the repeater 31 is also provided. On the other hand, the repeater 31 has a function of receiving data transmitted from the adjacent ZigBee slave unit 11 or the repeater 31 and transferring the data to another ZigBee slave unit 11 or the repeater 31.
The power source of the ZigBee slave unit 11 can be used by branching the power source from a power supply device that is originally installed for the signal controller 10 to drive a motor or lamp under its control. The power supply of the repeater 31 may be supplied by solar power generation by newly installing a solar panel and a storage battery.

  Further, as a first feature of the signal control device monitoring system according to the present embodiment, the repeater 31 arranged along the railroad line includes a ZigBee slave unit 11 adjacent to the ZigBee slave unit 11 of each signal controller 10, An example is that the distance from the repeater 31 is set to be equal to or less than a half distance (eg, 500 m) of a communicable distance (eg, 1000 m) of ZigBee communication. By having such an arrangement, even if one ZigBee slave unit 11 or repeater 31 breaks down, by communicating with the next closest ZigBee slave unit 11 or repeater 31 by jumping over the failed device, It is possible to avoid communication being disabled as a whole system.

  Next, as a second feature of the signal control device monitoring system according to the present embodiment, IEEE. In the 802.15.4 standard, communication using three frequency bands of 2.4 GHz, 902 to 928 MHz (hereinafter referred to as 920 MHz band), and 868 to 870 MHz is allowed, and in this embodiment, 2.4 GHz is included. The hardware of the ZigBee slave unit 11, the ZigBee master unit 21, and the repeater 31 is designed so that communication in two frequency bands of the 920 MHz band can be performed. By enabling communication in two frequency bands in this way, even if communication in one frequency band is interrupted due to radio wave interference or radio wave interference, communication in the other frequency band is continued, so that radio wave interference or It is possible to avoid communication failure as a whole system due to radio wave interference.

As a third feature of the signal control device monitoring system according to the present embodiment, data is normally transmitted using both of the two frequency bands, while one of the two frequency band communications is radio interference or If it becomes impossible due to radio interference, the data to be transmitted is degenerated and communication is continued. As described above, by degenerating the data to be transmitted, even if radio wave interference or radio wave interference occurs, a situation in which the state of each signal controller 10 cannot be grasped occurs by performing minimum data communication. Can be avoided. In addition, since data is normally transmitted using two frequency bands, it is possible to increase the amount of collected data in a normal communication state and perform detailed monitoring.
Here, the degeneration of transmission data refers to a mode in which collected data is thinned and transmitted, a mode in which important data, that is, data with higher priority is sequentially transmitted according to a predetermined priority, or data is compressed. And a transmission form. Further, data that could not be transmitted among the data collected from the signal controller 10 during the train operation time zone may be stored and transmitted during a time zone during which the night train does not operate.

In FIG. 1, only the signal controller 10 of the level crossing barrier is shown as the signal controller to be monitored. However, the signal controller is not limited thereto, and the control for controlling the signal device and the turning device is performed. A machine may be included.
In addition to the ZigBee communication function, the ZigBee repeater 31 arranged at the entrance and exit of the tunnel also has a wired communication function via an existing analog line and can be used as a preliminary communication in the event of an accident or failure in the tunnel. You may comprise.

Next, using FIG. 2 to FIG. 5, the signal control device monitoring server 20, the Zigbee slave device 11, the repeater 31, and the Zigbee master device constituting the signal control device monitoring system of this embodiment shown in FIG. 1. Each hardware configuration of 21 will be described.
As shown in FIG. 2, the signal control device monitoring server 20 includes a server computer 201 and a storage device 202 that stores files constituting the database. The server computer 201 stores IDs in the files in the storage device 202. And a registration unit 201A that realizes a function of registering data and a LAN communication unit 201B that realizes a function of performing communication with the ZigBee master unit 21 via the LAN. The storage device 202 may be a built-in memory of the server computer 201 or an external storage device.

  The storage device (database) 202 stores a ZigBee device configuration file 202A, a signal control device file 202B, and a rule configuration file 202C. Among these, in the device configuration file 202A, the group ID (2.4 GHz / 920 MHz) of the ZigBee device constituting the system, the device ID unique to the device, and the type of device (ZigBee master / ZigBee slave / repeater) The operation state of the device and the ID of the signal control device linked with the device are stored. In addition, the signal control device file 202B stores the ID of the signal control device connected to the ZigBee slave configuring the system, the type of the signal control device, and the operation state of the device.

  Further, in the rule configuration file 202C, the input method from the signal control device to the ZigBee slave, the sampling period of data from the signal control device (data acquisition interval), the default communication band (2.4 GHz / 920 MHz), communication Priority (data importance), information specifying how control data is output from the ZigBee slave unit to the signal control device, failure determination logic, window buffer size for each communication band, number of window buffers for each communication band , Waiting time to communicate with window buffer, waiting time for reception confirmation notification (ACK) for detecting radio interference, number of retries when waiting time exceeded, communication interval for checking line recovery when radio interference occurs, Stores the maximum communication failure time (determination value) and the like for determining the occurrence of radio interference.

  As shown in FIG. 3, the ZigBee slave unit 11 transmits and receives signals in the respective frequency bands to the first ZigBee communication module 111A that performs 2.4 GHz communication and the second ZigBee communication module 111B that performs 920 MHz band communication. Serial communication interfaces such as RS232C and RS485 to which data is input from the antennas 112A and 112B for performing input / output, the microcomputer 113 for executing input / output control and data processing, and the operation recording device provided in the signal controller 10 114 (hereinafter referred to as an RS232C interface).

  Further, the ZigBee slave unit 11 includes a contact input terminal (input port) 115 to which a signal from a switch or the like provided in a signal device controlled by the signal controller 10 is input, or a sensor provided in the signal device. A storage unit that stores a pulse input terminal 116 to which a pulse signal from the above is input, a spare terminal 117, an ID of a signal control device connected to the ZigBee slave, a type of the signal control device, and an operation state of the device (Signal control device file) 118, power input terminal 119, and the like.

  In the microcomputer 113, ZigBee communication is performed between the registration unit 113A that realizes a function of registering ID and data in the signal control device file in the storage unit 118, and other ZigBee devices via the communication modules 111A and 111B. ZigBee communication unit 113B that realizes the function of performing the above, the data acquisition unit 111C that acquires the data of the signal control device via the RS232C interface 114, the contact input terminal 115, and the pulse input terminal 116, the ZigBee communication unit 113B, and the data acquisition unit 111C A data buffering unit 111D for storing received and acquired data in time series and determining a communication state and the like, and a control data transmitting unit 111E for realizing a function of transmitting (outputting) control data to a signal control device are provided. ing.

  The signal control device file in the storage unit 118 includes the same content as the rule configuration file 202C stored in the storage device (database) 202 of the monitoring server 20 or a part thereof and the rule of the rule configuration file 202C. Rules related to ZigBee handsets are registered. The data of this file is transmitted and registered via the RS232C interface 114 by a notebook personal computer or the like at the installation location of the slave unit. It is also possible to use the ZigBee communication function to transfer and register the rule configuration file from the monitoring server 20 via the ZigBee master unit 21.

As shown in FIG. 4, the repeater 31 includes a first ZigBee communication module 311A that performs 2.4 GHz communication, a second ZigBee communication module 211B that performs 920 MHz band communication, antennas 312A and 312B, An input terminal 319 and the like are provided.
The communication modules 311A and 311B have a layer structure and a communication protocol according to the ZigBee communication standard. In addition, a relay function (hopping function) for transmitting received data as it is is provided.

As shown in FIG. 5, the ZigBee master unit 21 includes a first ZigBee communication module 211A that performs 2.4 GHz communication, a second ZigBee communication module 211B that performs 920 MHz band communication, and respective antennas 212A and 212B. LAN communication module 214 for performing communication via LAN between microcomputer 213 for executing input / output control and data processing and signal control device monitoring server 20 arranged in the command room, etc., and LAN connection terminal 215, a power input terminal 219, and the like.
The microcomputer 213 includes a ZigBee communication unit 213A that realizes a function of performing ZigBee communication with other ZigBee devices via the communication modules 211A and 211B, and the signal control device monitoring server 20 via the LAN. A LAN communication unit 213B that implements a function of performing communication is provided.

  Next, in the ZigBee handset 11, a buffer configuration for enabling communication in two frequency bands, and a specific example for allowing communication to continue even when radio wave interference or radio wave interference occurs. A method of the data transmission control process will be described with reference to FIGS.

FIG. 6 shows a buffer configuration in the ZigBee slave unit 11. 6A shows the configuration of the communication window buffer for the 2.4 GHz band, and FIG. 6B shows the configuration of the communication window buffer for the 920 MHz band.
As shown in FIGS. 6A and 6B, the communication window buffer for the 2.4 GHz band and the communication window buffer for the 920 MHz band are configured by a plurality of window buffers WB1, WB2, WB3,. The data acquired from the signal control device is sequentially stored in the window buffers WB1, WB2, WB3... As shown in FIG. If there is no abnormality in communication, the data is transmitted in the stored order. When the last buffer becomes full, the data is returned to the first transmitted buffer and stored.

7 and 8 show a method of data transmission control processing by the microcomputer 113 of the ZigBee slave unit 11. Among these, FIG. 7 shows an example of the procedure of the data transmission process, and FIG. 8 shows an example of the procedure of the communication recovery process.
First, the procedure of the data transmission process shown in FIG. 7 will be described. This data transmission process is executed every predetermined sampling period.
When the data transmission process is started, first, data is acquired from the signal control device (step S1). Subsequently, it is determined whether a communication abnormality (radio wave interference, radio wave interference) has occurred with reference to a communication abnormality flag described later (step S2). If it is determined that no communication abnormality has occurred (No), the process proceeds to step S3, the default communication band in the rule configuration file 202C is referred to, and the data transmission path (communication frequency band) acquired in step S1 is referred to. ) Is 2.4 GHz or 920 MHz.

If the transmission path is 2.4 GHz, the process proceeds to step S4. If the transmission path is 920 MHz, the process proceeds to step S6. In steps S4 and S6, it is determined whether or not there is an empty buffer in the corresponding window buffer. If it is determined that there is an empty buffer (Yes), the process proceeds to steps S5 and S7, and the acquired data is stored in the empty buffer. At this time, if the empty buffer is empty from the middle, it is stored continuously in an empty place, and if the buffer is full, the acquired data is stored in the next empty buffer.
On the other hand, if it is determined in steps S4 and S6 that there is no free buffer (No), the process proceeds to step S8, the acquired data is discarded, and the process returns to step S1.

  After the acquired data is stored in the empty buffer in steps S5 and S7, the process proceeds to step S9 to determine whether or not the buffer is full. If it is determined that the buffer is full (Yes), the process proceeds to step S11, and the data in the buffer is transmitted. If it is determined in step S9 that the buffer is not full (No), the process proceeds to step S10, where it is determined whether a predetermined transmission cycle has elapsed with reference to a timer. If it is determined that the predetermined transmission cycle has elapsed (Yes), the process proceeds to step S11, and the data in the buffer is transmitted. If it is determined in step S10 that the predetermined transmission cycle has not elapsed (No), the process returns to step S1.

After step S11, it is determined whether or not “ACK” (reception confirmation notification) has returned from another ZigBee device (ZigBee master unit or repeater) (step S12). If it is determined that “ACK” has returned (Yes), the process proceeds to step S13, where the data in the transmitted buffer is cleared, and the process ends.
If it is determined in step S12 that "ACK" (reception confirmation notification) has not returned (No), the process proceeds to step S14, and after the retry count is updated (+1), has the retry count reached the maximum value? It is determined whether or not (step S15). If it is determined that the number of retries has not reached the maximum value (No), the process returns to step S11, and the data in the buffer is transmitted again.

On the other hand, if it is determined in step S15 that the number of retries has reached the maximum value (Yes), the process proceeds to step S16, where the counter for counting the number of retries is cleared and the communication abnormality flag is set to “1”. As a result, it is possible to determine that a communication abnormality has occurred when radio interference or radio interference has occurred and data cannot be transmitted a predetermined number of times. A communication abnormality flag is provided for each frequency band.
Next, the process proceeds to step S17, the buffer on the transmission processing side at that time is locked so that data cannot be stored, and then the process returns to step S2.
When the communication abnormality flag is set to “1” in step S16 and then the process returns to step S2, it is determined that a communication abnormality has occurred (Yes), and the process proceeds to step S18. In step S18, it is determined whether or not the communication abnormality has occurred in both 2.4 GHz and 920 MHz. Here, if it is determined that both frequency bands are not (No), the process proceeds to step S19 to determine whether or not the priority of the already acquired data is high.

If it is determined that the priority is high (Yes), the process proceeds to step S13, it is determined whether or not the communication abnormality has occurred at 2.4 GHz, and if it is determined that it is 2.4 GHz, step S6 is performed. Then, it is determined whether or not there is an empty buffer in the window buffer on the 920 MHz side. If there is an empty buffer, data is stored (step S7).
On the other hand, if it is determined in step S20 that the communication abnormality has occurred is not 2.4 GHz (No), that is, 920 MHz, the process proceeds to step S4 to determine whether there is an empty buffer in the 2.4 GHz window buffer. If there is a vacancy, the data is stored (step S5).
On the other hand, if it is determined in step S19 that the priority of already acquired data is not high (No), the process jumps to step S8, discards the data, and returns to step S1.

Next, the procedure of the communication recovery process in FIG. 8 will be described. This communication recovery process is executed by a timer interrupt, for example.
In the communication recovery process, it is first determined by referring to the above-described communication abnormality flag whether or not a communication abnormality (radio wave interference or radio wave interference) has occurred (step S31). If it is determined that no communication abnormality has occurred (No), the communication recovery process is terminated without doing anything. On the other hand, if it determines with communication abnormality having generate | occur | produced by step S31 (Yes), it will progress to step S32 and will update a timer (+1). Then, it is determined whether or not a predetermined time (waiting time for detection of radio wave interference stored in the rule configuration file 202C) has elapsed with reference to the timer (step S33).

Here, if the predetermined time has not elapsed, the process returns to step S32, and if the predetermined time has elapsed, the process proceeds to step S34, and after resetting the timer, the communication abnormality flag is set at 2.4 GHz. It is determined whether or not there is (step S35). Then, in the next steps S36 and S37, dummy data is transmitted by communication using the frequency band for which the communication abnormality flag is set. Then, it is determined whether or not ACK (reception confirmation notification) has been received (step S38). If it is determined that ACK has not been received (No), the process returns to step S31, and S31 to S38 are repeated.
If it is determined in step S38 that ACK (reception confirmation notification) has been received (Yes), it is determined that the communication abnormality has returned to normal (radio wave interference or radio wave interference has been resolved), and the process proceeds to step S39, where the corresponding frequency The communication abnormality flag of the band is cleared, the window buffer is unlocked, and the communication recovery process is terminated.

  When both communication error flags of two frequency bands are set, even when the 2.4 GHz communication error flag is cleared in the above process, the communication recovery process of FIG. 8 is executed again by interruption. In step S31, it is determined that a communication abnormality is occurring (Yes). In step S35, it is determined that the communication error is not 2.4 GHz (No). The process proceeds to step S37, and dummy data is transmitted at 920 MHz. When ACK (reception confirmation notification) is received, the process proceeds to step S39, the 920 MHz band communication abnormality flag is cleared, the corresponding window buffer is unlocked, and the communication recovery process is terminated.

Next, the procedure of control information transmission processing for transmitting control information (command) from the signal control device monitoring server 20 to the signal control device will be described with reference to FIG.
In this control information transmission process, first, the monitoring server 20 refers to the configuration file 202A of the ZigBee device and the signal control device file 202B to identify the ZigBee slave unit linked to the control target signal control device (child device). (Acquire machine ID) (step S41). Next, referring to the default communication band in the rule configuration file 202C, the control information transmission path (communication frequency band) to the ZigBee slave unit identified in step S41 is acquired (step S42). Subsequently, the monitoring server 20 passes the ID and transmission path information of the destination ZigBee slave unit together with the control information to the ZigBee master unit 21 (step S43), and waits until a result is obtained.

When receiving the ZigBee slave unit ID, transmission path information, and control information from the monitoring server 20 (step S44), the ZigBee master unit 21 transmits control information to the ZigBee slave unit 11 using the designated transmission path (step S44). Step S45). When receiving the control information transmitted by the ZigBee master unit 21 (step S46), the ZigBee slave unit 11 outputs the received control information to the signal control device to be controlled (step S47).
Thereafter, the ZigBee slave unit 11 returns the control result to the ZigBee master unit 21 (step S48). When the ZigBee master unit 21 receives the control result from the ZigBee slave unit 11 (step S49), the received control result information is monitored by the monitoring server. 20 (step S50).
Then, the monitoring server 20 receives the control result (step S51), displays the received control result information on the display device (step S52), and ends the control information transmission process.

Next, in a current system that collects data from a signal control device using an analog line, a method for constructing a signal control device monitoring system that collects data using the ZigBee communication device of the above embodiment instead of the analog line Will be described with reference to FIGS.
In the current system that collects data from signal control equipment using an analog line, as shown in FIG. 10, each signal control equipment 10 installed along the railway collects analog input signals and contact inputs. A station device 50 that performs signal conversion is provided, and data is sent from the station device 50 to an aggregation device 61 arranged in the equipment room via an analog line 51, and further, an aggregation device 62 of a maintenance department through an analog line 52 Data is sent to the concentrator 63 in the command room and collected by the display control panel (monitoring computer) 20 ′. Note that a signal from a sensor provided in the signal control device can be input to the aggregation device 61 in the equipment room via the station device 50.

  Applying the above-described embodiment, when it is desired to change to a system in which data from each signal control device is collected by the display control panel (monitoring computer) 20 ′ using a ZigBee communication device instead of the analog line 51 of FIG. A terminal for receiving an analog signal output from the station device 50 and a circuit for determining the signal are provided in the ZigBee slave unit 11 having the configuration shown in FIG. And as this ZigBee subunit | mobile_unit 11 is connected to each station apparatus 50, as shown by the continuous line in FIG. 11, by connecting the ZigBee main | base station 21 to the consolidating apparatus 61, ZigBee communication WHEREIN: A system for transmitting data to the display control panel (monitoring computer) 20 ′ can be constructed. In the system of FIG. 11, the ZigBee slave unit 11 is indirectly connected to the signal control device via the station device 50. Furthermore, as shown by a broken line in FIG. 11, it is also possible to configure such that existing wired communication type signal control devices are connected together.

Note that a LAN may be provided and connected between the ZigBee master unit 21 and the display control panel (monitoring computer) 20 ′ instead of the analog line 52 and the aggregation devices 61 to 63. Further, by using the ZigBee device, as shown in FIG. 12, it is possible to construct a system in which a signal control device including the station device 50 and a signal control device not including the station device 50 are mixed. .
As shown in FIG. 11 and FIG. 12, in the system having the analog line 52 and the aggregation devices 61 to 63, the ZigBee master unit 21 is a communication device that forms a wired communication network in a computer 20 ′ as a monitoring device. It will be connected indirectly via.

  Although the invention made by the present inventor has been specifically described based on the embodiment, the present invention is not limited to the embodiment. For example, in the above-described embodiment, the signal control device monitoring system configured to perform communication using two frequency bands of 2.4 GHz and 920 MHz band has been described. However, a total of 868-870 MHz frequency band is added. You may comprise so that communication using three frequency bands may be performed.

In the embodiment, IEEE. Although the system for transmitting data by ZigBee communication according to the 802.15.4 standard has been described, the system may be configured to perform communication according to another wireless communication standard. Furthermore, it may be configured such that communication according to a plurality of different wireless communication standards can be performed in parallel.
In the above embodiment, the repeater 31 has only the function of transmitting the received data as it is, but the repeater 31 also has no function of detecting communication abnormality (radio wave interference or radio wave disturbance) or communication abnormality. A data transmission function using one frequency band and a function for degenerating data may be provided.

10 Signal controller (signal control equipment)
11 Zigbee handset 20 Signal control equipment monitoring server (monitoring device)
21 ZigBee main unit 22 LAN
31 repeater

Claims (8)

A railway facility monitoring system comprising one or more signal control devices arranged along a railway line, and a monitoring device that remotely monitors the operation state of these signal control devices,
A main wireless communication means connected directly or indirectly to the monitoring device and capable of wireless communication using different frequency bands;
Subordinate radio communication means connected directly or indirectly to the signal control device and capable of radio communication using the plurality of frequency bands;
Relay means having a function of transferring data received by wireless communication using the plurality of frequency bands,
The main radio communication means, the subordinate radio communication means, and the relay means are arranged along a railway line at a distance of one half or less of a communicable distance by the radio communication. A characteristic railway equipment monitoring system.   The subordinate radio communication means has a function of determining a communication state, and when all radio communication in the plurality of frequency bands is possible, performs radio communication in all frequency bands and transmits data, 2. When wireless communication using any one of a plurality of frequency bands is impossible, data is transmitted by wireless communication using another frequency band in which wireless communication is possible. The equipment monitoring system for railways described in 1.   3. The railway facility monitoring system according to claim 2, wherein the subordinate radio communication unit transmits the data subjected to the degeneration processing when radio communication using any one of the frequency bands is impossible. 4. .   4. The railway according to claim 3, wherein priority is given to data to be transmitted according to the type thereof, and the degeneration processing is processing that does not target the data with low priority as a transmission target. Equipment monitoring system. In a railway facility monitoring system comprising one or more signal control devices arranged along a railway line and a monitoring device that remotely monitors the operation state of these signal control devices, the signal control device Or a data communication device that performs communication by being directly or indirectly connected to the monitoring device,
A data communication apparatus configured to be capable of wireless communication using all or any one of a plurality of different frequency bands.   A function of determining a communication state of wireless communication using the plurality of different frequency bands, and when all wireless communication of the plurality of frequency bands is possible, the wireless communication of all frequency bands is executed to obtain data. Transmitting and transmitting data by wireless communication using another frequency band capable of wireless communication when wireless communication using any one of the plurality of frequency bands is impossible The data communication apparatus according to claim 5.   The data communication apparatus according to claim 6, wherein when the wireless communication using any one of the frequency bands is impossible, the data subjected to the degeneration process is transmitted.   8. The data communication according to claim 7, wherein priority is given to data to be transmitted according to a type thereof, and the degeneration processing is processing that does not target data with low priority. apparatus.

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