JP2019125990A - Radio communication system and relay device - Google Patents

Abstract

To detect a fault in a wired section connecting a plurality of relay devices in a radio communication system.SOLUTION: The radio communication system of the present invention includes a first relay device and a second relay device that relay radio communication between a plurality of radio mobile stations. The first relay device and the second relay device are wire-connected through a wired connection section. The first relay device transmits a check signal to the second relay device via the wired connection section and the second relay device transmits a first abnormality notice which is information indicating the occurrence of a fault in wired connection to the outside of the second relay device on the basis of a reception situation of the check signal.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wireless communication system and a relay apparatus.

  As one of the tests to confirm the soundness of the wireless device in the wireless communication system, the radio wave transmitted by the transmitting unit of the wireless device is internally folded back without being transmitted from the antenna to the outside, and is received by the receiving unit of the wireless device There is a loop back test to check whether the transmission and reception operation is correctly performed.

  However, since the antenna is not used in the aliasing test, it can not be confirmed whether radio waves are normally transmitted from the antenna of the wireless device. For example, even if the antenna is in an unusable state, such as when the cable between the wireless device and the antenna is broken, a defect in the antenna is not detected in the return test. In particular, in a wireless communication system in which transmission and reception of radio waves are not normally performed, such as a train guard radio system, but is performed only in an emergency, there is a risk that the user operates for a long time without noticing a failure of the antenna.

  Therefore, Patent Document 1 discloses a method of performing a transmission / reception test that detects a failure of an antenna of a wireless device without causing a failure in the operation of a wireless communication system. According to the method of Patent Document 1, the transmission / reception test can be performed within the operation time even in the wireless communication system that transmits information only when necessary.

JP, 2012-165092, A

  However, in the test method of Patent Document 1, when the wireless communication system includes a plurality of relay devices connected by wire, the test signal does not transmit the wired connection section between the relay devices, so that the wired connection section is tested. I can not Therefore, there is a possibility that the wireless communication system is operated without the user noticing the trouble of the wired connection section between the relay devices.

  An object of the present invention is to detect a fault in a wired section between a plurality of relay devices in a wireless communication system.

  A wireless communication system according to the present invention is a wireless communication system including a first relay apparatus and a second relay apparatus for relaying wireless communication between a plurality of wireless mobile stations, the first relay apparatus and the second relay The first relay device transmits a check signal to the second relay device via the wire connection section, and the second relay apparatus receives the check signal. Based on the situation, a first abnormality notification, which is information indicating that a failure has occurred in the wired connection section, is transmitted to the outside of the second relay device.

  According to the wireless communication system of the present invention, since the inspection signal is transmitted from the first relay apparatus to the second relay apparatus through the wired connection section, the second relay apparatus detects a fault occurring in the wired connection section. can do.

FIG. 1 is a schematic configuration diagram of a wireless communication system according to a first embodiment. It is a block diagram of a relay apparatus. It is a block diagram of the radio | wireless communications system which has three relay apparatuses. 5 is a flowchart showing an operation of a relay device of a master station in the abnormality detection process of the first embodiment. 7 is a flowchart showing an operation of a relay device of a slave station in the abnormality detection process of the first embodiment. FIG. 7 is a diagram showing a timeline of the relay device of the first embodiment. 15 is a flowchart showing an operation of a relay device of a master station in the abnormality detection process of the second embodiment. 15 is a flowchart showing an operation of a relay device of a slave station in the abnormality detection process of the second embodiment. FIG. 7 is a diagram showing a timeline of the relay device of the second embodiment.

<A. Embodiment 1>
FIG. 1 is a schematic configuration diagram of a wireless communication system according to a first embodiment. In the present embodiment, a description will be given on the assumption that a train guard radio system is taken as an example of a radio communication system, but another radio communication system may be used.

  The radio communication system includes a radio mobile station 1A mounted on a train A, a radio mobile station 1B mounted on a train B, relay devices 2A and 2B relaying radio communication between the radio mobile stations 1A and 1B, and a relay The monitoring apparatuses 3A and 3B which monitor apparatus 2A and 2B, respectively are provided.

  FIG. 2 shows the configuration of the relay device 2A. As shown in FIG. 2, the relay device 2A includes an antenna 21A, a transmitting unit 22A that transmits a signal via the antenna 21A or a wired connection section, and a receiving unit 23A that receives a signal via the antenna 21A or a wired connection section. And have. The configuration of the relay apparatus 2B is the same as the configuration of the relay apparatus 2A, but when referring to the configuration of the relay apparatus 2B below, the suffix B is added to the reference code as in "the receiving unit 23B". , And the configuration of the relay device 2A.

  When the radio mobile station 1A transmits an alerting signal, the receiver 23A of the relay device 2A receives the alerting signal via the antenna 21A. Then, the transmitter 22A of the relay device 2A transmits an alert signal to another wireless mobile station, here the wireless mobile station 1B, via the antenna 21A. This operation is referred to as "relay alert".

  The relay device 2A and the relay device 2B are connected by wire. In other words, the relay device 2A and the relay device 2B are wired connection sections. In the wired connection section, current loop communication is performed. The relay device 2A transmits a connection signal to the relay device 2B via the wired connection section. When the relay device 2A issues a relay notification during transmission of a connection signal, the relay device 2B also transmits a notification signal to another wireless mobile station, here the wireless mobile station 1B in synchronization with this. This operation is referred to as "connected relay notification".

  The radio mobile station 1B receives a report signal by one or both of a relay report from the relay apparatus 2A and a linked relay report from the relay apparatus 2B. When the radio mobile station 1B receives the alarm signal, the train B is stopped.

  One of relay apparatus 2A and relay apparatus 2B is set as a master station, and the other is set as a slave station. This setting is set by, for example, hardware such as a dip switch or software.

  Although two relay apparatuses are shown in FIG. 1, the number of relay apparatuses constituting the wireless communication system is not limited to two. For example, as shown in FIG. 3, the number of relay apparatuses may be three. In the wireless communication system shown in FIG. 3, the relay device 2A and the relay device 2B are connected by wire, and the relay device 2B and the relay device 2C are connected by wire. That is, between the relay device 2A and the relay device 2B, and further between the relay device 2B and the relay device 2C is a wired connection section. Current loop communication is performed in these wired connection sections. Further, the monitoring device 3C is connected to the relay device 2C. One of the relay devices 2A, 2B, 2C is set as a master station. For example, the relay device 2A is set as a master station, and the other relay devices 2B and 2C are set as slave stations.

  Next, an abnormality detection process of a wired connection section between relay devices will be described. FIG. 4 is a flowchart showing the operation of the relay device of the master station regarding the abnormality detection processing. Hereinafter, the relay device 2A is used as a master station, and the operation of the relay device 2A will be described along the flowchart of FIG. That is, the relay device 2A is a master station, and the relay device 2B is a slave station.

  First, the transmission unit 22A of the relay device 2A transmits an inspection signal to the relay device 2B (step S101). This step is performed, for example, simultaneously with the start of operation of the wireless communication system. Here, the pulse width of the inspection signal is, for example, 0.5 seconds. Even when the connection signal is not transmitted to the relay device 2B, the relay device 2A can perform the abnormality detection of the wired connection section during the operation of the wireless communication system by pulse transmission of the inspection signal.

  The transmitter 22A determines whether the cycle T1 has elapsed since the transmission of the previous inspection signal in step S101 (step S102). Here, the period T1 is, for example, one second. If the cycle T1 has not elapsed, step S102 is repeated, and if it has elapsed, the process returns to step S101. That is, the transmission unit 22A repeats transmission of the inspection signal at a cycle T1.

  FIG. 5 is a flowchart showing the operation of the relay device of the slave station regarding the abnormality detection processing. Hereinafter, the relay device 2B is used as a slave station, and the operation of the relay device 2B will be described along the flowchart of FIG. First, the receiving unit 23B of the relay device 2B determines whether the cycle T1 has elapsed since the reception of the previous inspection signal (step S201). This step is performed, for example, simultaneously with the start of operation of the wireless communication system. In step S201, if the cycle T1 has not elapsed from the reception of the previous inspection signal, the receiver 23B repeats step S201.

  In step S201, when a predetermined period has elapsed since the previous reception of the inspection signal, the receiver 23B determines whether a new inspection signal has been received (step S202). When the receiver 23B newly receives an inspection signal in step S202, the process of the relay device 2B returns to step S201. If the receiver 23B does not newly receive an inspection signal in step S202, the transmitter 23A determines that an abnormality has occurred in the wired connection section between the relay apparatuses 2A and 2B, and an abnormality notification indicating information to that effect. Are transmitted to the monitoring device 3B (step S203). An abnormality notification that an abnormality has occurred in the wired connection section between the relay devices 2A and 2B is referred to as a first abnormality notification.

  FIG. 6 shows a timeline of the relay device in the first embodiment. In FIG. 6, the transmission cycle T1 of the inspection signal transmitted from the relay device 2A to the relay device 2B is 1 second, and the pulse width is 0.5 second. The relay device 2A transmits the connection signal to the relay device 2B in synchronization with the third pulse of the inspection signal. The transmission period of the connection signal is 6 seconds. Three seconds after the start of transmission of the connection signal, the relay device 2A issues a relay alert. The relay device 2B issues a connection relay notification in synchronization with the relay notification of the relay device 2A.

  The relay device 2B confirms the soundness of the wired connection section by monitoring the reception of the inspection signal from the relay device 2A. When the inspection signal from the relay device 2A is interrupted, the relay device 2B transmits an abnormality detection to the monitoring device 3B.

  According to the above method, the monitoring device connected to each relay device can monitor the state of the wired connection section. In the above description, the current loop communication is performed in the wired connection section between the relay devices. However, other communication methods such as serial communication or Ethernet (registered trademark) communication may be used.

  However, in the current loop communication, it is possible to switch the transmitting side and the receiving side of the inspection signal. Therefore, in the above description, although the inspection signal is transmitted from the relay device 2A of the master station to the relay device 2B of the slave station, it is also possible to transmit the inspection signal from the slave station to the master station . In this case, it is possible to collect the soundness of all relay devices in the parent station.

  As described above, the radio communication system according to the first embodiment is the relay apparatus 2A and the second relay apparatus, which are the first relay apparatuses for relaying the radio communication between the plurality of radio mobile stations 1A and 1B. A relay device 2B is provided. The relay device 2A and the relay device 2B are wired connection sections connected by wire, and the relay device 2A transmits an inspection signal to the relay device 2B via the wired connection section. The relay device 2B transmits a first abnormality notification, which is information indicating that a failure has occurred in the wired connection section, to the outside of the relay device 2B based on the reception status of the inspection signal. Thus, when the connection of the wired connection section is cut off by transmitting the inspection signal to the wired connection section of the relay apparatuses 2A and 2B, the relay apparatus 2B on the receiving side of the inspection signal may detect a fault. it can. Therefore, the soundness of the wireless communication system can be maintained.

  In the wireless communication system according to the first embodiment, the relay device 2A transmits an inspection signal to the relay device 2B at a constant cycle T1, and the relay device 2B does not receive the inspection signal at a constant cycle T1. The abnormality notification is transmitted to the outside of the relay device 2B. Therefore, a fault in the wired connection section can be detected early.

  Further, in the wireless communication system of the first embodiment, the relay devices 2A and 2B relay the wireless communication of the wireless mobile stations 1A and 1B mounted on the trains. For example, in a protected radio system of a train, transmission and reception of radio waves are performed only in an emergency, so the system is operated for a long time without the user being aware of a fault in the wired connection section of the relay devices 2A and 2B. There is a problem that wireless communication can not be performed. However, in the wireless communication system according to the first embodiment, since the failure of the wired connection section of the relay devices 2A and 2B is detected, the above problem is solved.

<B. Second Embodiment>
The configuration of the wireless communication system of the second embodiment is the same as that of the first embodiment and is as shown in FIG. The configuration of each relay device in the wireless communication system of the second embodiment is the same as that of the first embodiment and is as shown in FIG.

  Next, an abnormality detection process of a wired connection section between relay devices will be described. In the second embodiment, the transmission schedule of the inspection signal is once a day, and the relay device of the slave station of the relay device of the master station shares the scheduled transmission time of the inspection signal. The relay device of the slave station performs the abnormality detection on the deviation of the device time in addition to the abnormality detection on the failure of the wired connection section through the reception state of the inspection signal.

  FIG. 7 is a flowchart showing the operation of the relay device of the master station regarding abnormality detection processing. Hereinafter, the relay device 2A is used as a master station, and the operation of the relay device 2A will be described along the flowchart of FIG. That is, the relay device 2A is a master station, and the relay device 2B is a slave station.

  First, the transmission unit 22A of the relay device 2A recognizes the current time by the built-in clock of the relay device 2A, and determines whether the current time is the scheduled transmission time of the inspection signal (step S301). This step is performed, for example, simultaneously with the start of operation of the wireless communication system. If the current time is not the scheduled transmission time, the transmitter 22A repeats step S301.

  If the current time is the scheduled transmission time in step S301, the transmission unit 22A transmits an inspection signal to the relay device 2B (step S302). The inspection signal may be one pulse or a plurality of pulses transmitted in a constant cycle. In FIG. 9, five pulses transmitted at one second intervals are used as inspection signals. The pulse width of the inspection signal is, for example, 0.5 seconds, which is different from the pulse width of the coupled signal.

  FIG. 8 is a flowchart showing the operation of the relay device of the slave station regarding the abnormality detection processing. Hereinafter, the relay device 2B is used as a slave station, and the operation of the relay device 2B will be described along the flowchart of FIG.

  First, the relay device 2B recognizes the current time by the built-in clock, and determines whether the current time is within the inspection signal confirmation period (step S401). The inspection signal confirmation period is a fixed period including the scheduled transmission time, and is, for example, a period having a width of time T2 before and after the scheduled transmission time. If the current time is not within the inspection signal confirmation period, the relay device 2B repeats step S401.

  If it is determined in step S401 that the current time is within the inspection signal confirmation period, it is determined whether the reception unit 23B has received an inspection signal (step S402). When the receiver 23B receives the inspection signal in step S402, the receiver 23B determines whether the time difference between the reception time and the scheduled transmission time is equal to or more than the time T3 which is a predetermined threshold (step S403). . When the inspection signal consists of a plurality of pulses, the reception time to be compared in step S403 is the reception time of the last pulse. In addition, it is T3 <T2.

  In step S403, if the time difference between the reception time and the scheduled transmission time is equal to or longer than time T3, transmission unit 23B determines that time lag occurs between relay device 2B and relay device 2A, and an abnormality notification indicating that effect Are transmitted to the monitoring device 3B (step S404). This abnormality notification is a second abnormality notification.

  In step S403, if the time difference between the reception time and the scheduled transmission time is less than the time T2, the relay device 2B updates the scheduled transmission time to the next scheduled transmission time (step S405), and returns to step S401.

  If the reception unit 23B does not receive the inspection signal in step S402, the reception unit 23B recognizes the current time by the built-in clock and determines whether the current time is within the inspection signal confirmation period (step S406). If the current time is not within the inspection signal confirmation period in step S406, the transmission unit 23B determines that a failure has occurred in the wired section between the relay devices 2A and 2B, and transmits an abnormality notification indicating that to the monitoring device 3B. (Step S407). This abnormality notification is a first abnormality notification.

  FIG. 9 shows a timeline of the relay device in the second embodiment. FIG. 9 shows a timeline in the case where an inspection signal is transmitted from the relay device 2A of the master station to the relay device 2B of the slave station at scheduled times once a day. The inspection signal has a pulse width of 0.5 seconds and consists of 5 pulses transmitted in a 1 second cycle. The relay device 2A transmits the connection signal to the relay device 2B in synchronization with the fifth pulse of the inspection signal. The transmission period of the connection signal is 6 seconds. Three seconds after the start of transmission of the connection signal, the relay device 2A issues a relay alert. The relay device 2B issues a connection relay notification in synchronization with the relay notification of the relay device 2A.

  The relay device 2B confirms that no failure has occurred in the wired connection section with the relay device 2A by receiving the inspection signal. Furthermore, when the fifth pulse which is the last pulse of the inspection signal is received, the reception time is compared with the transmission scheduled time. If the time difference between the two is not equal to or greater than the threshold value, the relay device 2B determines that a time shift abnormality has occurred with the relay device 2A, and transmits an abnormality notification indicating information to that effect to the monitoring device 3B.

  As described above, in the wireless communication system according to the second embodiment, the relay device 2A, which is the first relay device, sends an inspection signal to the relay device 2B, which is the second relay device, at a predetermined scheduled transmission time. When the relay device 2B does not receive the inspection signal in the inspection signal confirmation period including the scheduled transmission time, the relay device 2B transmits the first abnormality notification to the outside of the relay device 2B. In addition, when the reception time of the inspection signal is within the inspection signal confirmation period, and the time difference between the reception time of the inspection signal and the scheduled transmission time is equal to or more than a predetermined time T3, relay device 2B is relay device 2B. And the relay apparatus 2A transmit a second abnormality notification, which is information indicating that a time lag has occurred, to the outside of the relay apparatus 2B. Therefore, according to the wireless communication system of the second embodiment, it is possible to detect an abnormality in the wired connection section between the relay devices 2A and 2B and to detect a time shift between the relay devices 2A and 2B.

  In the present invention, within the scope of the invention, each embodiment can be freely combined, or each embodiment can be appropriately modified or omitted.

  1A, 1B radio mobile station, 2A, 2B, 2C relay device, 3A, 3B, 3C monitoring device, 21A antenna, 22A transmitter, 23A, 23B receiver.

Claims (6)

What is claimed is: 1. A wireless communication system comprising: a first relay apparatus for relaying wireless communication between a plurality of wireless mobile stations; and a second relay apparatus,
The first relay apparatus and the second relay apparatus are wired connection sections connected by wire.
The first relay device transmits an inspection signal to the second relay device via the wired connection section;
The second relay device transmits a first abnormality notification, which is information indicating that a failure has occurred in the wired connection section, to the outside of the second relay device based on the reception status of the inspection signal.
Wireless communication system. The first relay device transmits the inspection signal to the second relay device at a constant cycle,
The second relay apparatus transmits the first abnormality notification to the outside of the second relay apparatus when the inspection signal is not received at the predetermined cycle.
The wireless communication system according to claim 1. The first relay device transmits the inspection signal to the second relay device at a predetermined transmission scheduled time,
The second relay apparatus transmits the first abnormality notification to the outside of the second relay apparatus when the inspection signal is not received in the inspection signal confirmation period including the scheduled transmission time, and the inspection signal The second relay apparatus and the first relay apparatus when the reception time of the second signal is within the inspection signal confirmation period and the time difference between the reception time of the inspection signal and the scheduled transmission time is equal to or more than a predetermined time. Transmitting, to the outside of the second relay device, a second abnormality notification that is information indicating that a time shift has occurred between the second relay device and the second relay device.
The wireless communication system according to claim 1. The first relay device and the second relay device relay wireless communication of a wireless mobile station mounted on a train.
The wireless communication system according to any one of claims 1 to 3. It is used for the radio | wireless communications system of any one of Claim 1 to 4,
Sending the inspection signal to the other relay apparatus connected by wire;
Relay device. It is used for the radio | wireless communications system of any one of Claim 1 to 4,
The first abnormality notification is transmitted to the outside of the terminal based on the reception status of the inspection signal from another relay device connected by wire.
Relay device.

Images