Wireless communication system, in-vehicle device, and ground device

Abstract

To provide a wireless communication system capable of reducing the excessive stoppage of a train when an abnormality occurs in a railroad crossing.SOLUTION: The wireless communication system comprises: a ground device 10 that transmits a wireless signal indicating a state in a railroad crossing; and an on-board device 20 that is mounted on a train and receives the wireless signal. The ground device 10 transmits a wireless signal indicating an abnormal state in the railroad crossing when an abnormality has occurred in the railroad crossing, and a wireless signal indicating a normal state in the railroad crossing when there is no abnormality in the railroad crossing. The on-board device 20 determines, when the received wireless signal indicates the abnormal state in the railroad crossing, a running state to be taken by the train on the basis of a distance from the train to the railroad crossing, and notifies a driver of the train of the determination result of the running state to be taken by the train.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a wireless communication system, and more particularly to a wireless communication system for railroad crossing protection that prevents train accidents within railroad crossings.

Background Art

[0002] Development of a wireless communication system for railroad crossing protection that prevents train accidents within railroad crossings is underway. For example, in Patent Document 1 below, when a train approaches a railroad crossing, the railroad crossing device lowers a barrier and determines the state inside the railroad crossing. When an abnormality inside the railroad crossing is detected, a wireless communication system that notifies the driver of the train of the occurrence of the abnormality is disclosed. According to this wireless communication system, the driver of the train can know in real time the occurrence of an abnormality inside the railroad crossing, and by decelerating the train in advance, the train can surely be stopped before reaching the railroad crossing.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The wireless communication system of Patent Document 1 only notifies the driver of the train of the occurrence of an abnormality inside the railroad crossing. Therefore, the driver who receives the notification has no choice but to stop the train. However, depending on the content of the abnormality and the positional relationship with the railroad crossing, it may be considered that it is sufficient to proceed slowly without stopping the train. Excessive train stops cause significant disruptions to the train schedule and impose burdens on both the driver and the passengers.

[0005] The present disclosure has been made to solve the above problems, and an object thereof is to provide a wireless communication system that can reduce excessive train stops when an abnormality occurs inside a railroad crossing. [Means for solving the problem]

[0006] The wireless communication system according to this disclosure comprises a ground device that transmits a wireless signal indicating the condition inside a level crossing, and an on-board device mounted on a train that receives the wireless signal, wherein the ground device transmits the wireless signal indicating that the condition inside the level crossing is abnormal when an abnormality occurs inside the level crossing, and transmits the wireless signal indicating that the condition inside the level crossing is normal when there is no abnormality inside the level crossing, and the on-board device, when the received wireless signal indicates that the condition inside the level crossing is abnormal, determines the operating state that the train should take based on the distance from the train to the level crossing, and notifies the train driver of the result of the determination of the operating state that the train should take. [Effects of the Invention]

[0007] According to this disclosure, the ground equipment transmits not only a radio signal indicating that the conditions within the level crossing are abnormal, but also a radio signal indicating that the conditions within the level crossing are normal, and the onboard equipment determines the operating state that the train should take based on the distance from the train to the level crossing where the abnormality occurred. For example, when the train is far from the level crossing where the abnormality occurred and there is no need to stop the train, it can decide to continue its normal operation or slow down. Thus, excessive train stops can be reduced. [Brief explanation of the drawing]

[0008] [Figure 1] This is a block diagram showing the configuration of the wireless communication system according to Embodiment 1. [Figure 2] This is a block diagram showing the configuration of the wireless transmission unit. [Figure 3] This is a block diagram showing the configuration of the wireless communication system according to Embodiment 2. [Figure 4] This is a block diagram showing the configuration of the wireless communication system according to Embodiment 3. [Modes for carrying out the invention]

[0009] <Embodiment 1> Figure 1 is a block diagram showing the configuration of a wireless communication system according to Embodiment 1. This wireless communication system is a wireless communication system for level crossing protection that wirelessly notifies trains of abnormalities occurring at level crossings, and consists of a ground device 10 installed at the level crossing and an on-board device 20 mounted on the train.

[0010] The ground equipment 10 consists of a level crossing device 11, a train detection unit 12, a level crossing control unit 13, an abnormality notification unit 14, a wireless transmission unit 15, and an antenna 16.

[0011] Level crossing equipment 11 refers to equipment such as warning signals and barriers installed at level crossings on train tracks.

[0012] The train detection unit 12 detects the approach and passage of a train to the level crossing and notifies the level crossing control unit 13. Any train detection method is acceptable, such as a track circuit system or a ground beacon / on-board beacon system.

[0013] The level crossing control unit 13 controls the level crossing equipment 11 in response to notifications from the train detection unit 12. For example, if the train detection unit 12 notifies that a train is approaching, the level crossing control unit 13 performs actions on the level crossing equipment 11 such as sounding the alarm and lowering the barrier. If the train detection unit 12 notifies that a train has passed, the level crossing control unit 13 performs actions on the level crossing equipment 11 such as stopping the alarm and raising the barrier.

[0014] Furthermore, the level crossing control unit 13 notifies the abnormality notification unit 14 of its own operating status, specifically whether it is in a state where it is performing control when a train is approaching or when it is performing control when a train is passing. Hereinafter, the operating state in which the level crossing control unit 13 is performing control when a train is approaching will be referred to as the "train approaching state," and the operating state in which the level crossing control unit 13 is performing control when a train is passing will be referred to as the "train passing state."

[0015] Furthermore, the level crossing control unit 13 notifies the wireless transmission unit 15 of the location of the level crossing to be controlled (i.e., the installation location of the level crossing equipment 11) and the identification information of the level crossing. The location of the level crossing is expressed, for example, as the distance from a specific reference point. Hereinafter, the identification information of the level crossing may also be referred to as the "level crossing ID".

[0016] The abnormality notification unit 14 is equipped with an emergency button that can be pressed by a person who notices an abnormality in the level crossing, as well as an abnormality detector such as a camera and radar that automatically detect obstacles in the level crossing. Based on the output signals from these detectors, it determines the state of the level crossing and notifies the wireless transmission unit 15 of whether or not there is an abnormality in the level crossing. More specifically, when the level crossing control unit 13 detects that a train is approaching, the abnormality notification unit 14 starts monitoring the state of the level crossing. If no abnormality is detected, it sends a notification to the wireless transmission unit 15 indicating that the level crossing is in a normal state. If an abnormality is detected, it sends a notification to the wireless transmission unit 15 indicating that the level crossing is in an abnormal state. Hereinafter, the notification of the state of the level crossing (presence or absence of an abnormality) sent from the abnormality notification unit 14 to the wireless transmission unit 15 will be called a "level crossing state notification," of which a notification indicating that the level crossing is in a normal state will be called a "level crossing normal notification," and a notification indicating that the level crossing is in an abnormal state will be called a "level crossing abnormal notification."

[0017] Here, the abnormality notification unit 14 detects an abnormality within the level crossing and sends a level crossing abnormality notification to the wireless transmission unit 15. Once the abnormality is resolved and no further abnormalities are detected, it sends a level crossing normality notification to the wireless transmission unit 15. Furthermore, when the level crossing control unit 13 enters a train passage state, the abnormality notification unit 14 terminates its monitoring of the conditions within the level crossing. In other words, the abnormality notification unit 14 notifies the wireless transmission unit 15 in real time whether the conditions within the level crossing are normal or abnormal from the time the level crossing control unit 13 enters a train approach state until the train passes state.

[0018] When the wireless transmission unit 15 receives a notification from the abnormality notification unit 14 indicating the status inside the level crossing (level crossing status notification), it obtains the location information of the level crossing from the level crossing control unit 13 and transmits information indicating whether the status inside the level crossing is normal or abnormal, as well as the location information of the level crossing, as a wireless signal from the antenna 16. Furthermore, when the level crossing control unit 13 indicates that a train has passed, the wireless transmission unit 15 stops transmitting the wireless signal.

[0019] The detailed configuration of the wireless transmission unit 15 is shown in FIG. 2. As shown in FIG. 2, the wireless transmission unit 15 includes a transmission signal processing unit 151, a transmission processing unit 152, and a transmission control unit 153.

[0020] The transmission control unit 153 controls the transmission of the wireless signal by controlling the transmission signal processing unit 151 and the transmission processing unit 152 based on the state inside the crossing notified by the abnormality notification unit 14, and the position information and identification information (crossing ID) of the crossing notified by the crossing control unit 13. The transmission signal processing unit 151 generates a transmission signal including the state inside the crossing and the information of the position of the crossing acquired by the transmission control unit 153. The transmission processing unit 152 transmits the transmission signal generated by the transmission signal processing unit 151 as a wireless signal from the antenna 16, and the transmission control unit 153 controls the start and stop of the transmission of the wireless signal by the transmission processing unit 152.

[0021] Next, the on-vehicle device 20 will be described. The on-vehicle device 20 includes a wireless reception unit 21, an antenna 22, an operation determination unit 23, a position information acquisition unit 24, and an operation instruction notification unit 25.

[0022] The antenna 22 receives the wireless transmission signal transmitted via the antenna 16 of the on-vehicle device 20.

[0023] The wireless reception unit 21 receives the wireless signal transmitted from the ground device 10 via the antenna 22, and performs demodulation processing on the wireless signal to extract the state inside the crossing and the information of the position of the crossing included in the wireless signal, and sends it to the operation determination unit 23.

[0024] The position information acquisition unit 24 acquires the position information of the train (hereinafter sometimes referred to as "own train") equipped with the wireless reception unit 21 and notifies the operation determination unit 23. There is no restriction on the method of acquiring the position information of the train. For example, the position of the train may be acquired using any means capable of specifying the position of the train, such as ground elements on the line, rotation of wheels, GNSS (Global Navigation Satellite System), etc.

[0025] The operation determination unit 23 calculates the distance from the vehicle to the level crossing based on the location information of the level crossing obtained from the wireless receiver unit 21 and the location information of the vehicle obtained from the location information acquisition unit 24. Then, the operation determination unit 23 determines the operating state that the vehicle should take (normal operation, slow speed, or stop) based on the calculated distance from the vehicle to the level crossing and the conditions inside the level crossing obtained from the wireless receiver unit 21, and notifies the operation instruction notification unit 25 of the result of that determination.

[0026] Specifically, if the conditions within the level crossing are normal, the operation determination unit 23 determines that the vehicle should operate normally. If the conditions within the level crossing are abnormal, the operation determination unit 23 determines the appropriate operating state for the vehicle based on the distance from the vehicle to the level crossing. That is, if the distance from the vehicle to the level crossing is greater than or equal to a predetermined threshold, the operation determination unit 23 determines that the vehicle should proceed slowly, and if the distance from the vehicle to the level crossing is less than the threshold, the vehicle should stop. The threshold is defined as the distance at which the vehicle would enter the level crossing if it did not stop.

[0027] Furthermore, if the onboard device 20 is simultaneously receiving wireless signals from multiple ground devices 10, the operation determination unit 23 should determine the operating state that the vehicle should take based on information extracted from the wireless signals from the ground device 10 of the level crossing closest to the vehicle, or from the ground device 10 of a level crossing within a certain distance from the vehicle.

[0028] Furthermore, if the wireless signal received from the ground device 10 contains only information about the location of the level crossing (and does not contain information about the conditions inside the level crossing), it is considered that there is some kind of malfunction in the ground device 10, and the operation determination unit 23 may perform the same processing as when there is a malfunction inside the level crossing.

[0029] The operation instruction notification unit 25 instructs the driver to enter the operating state that the vehicle should be in, by notifying the driver of the operating state that the operation determination unit 23 has notified the driver of. There are no restrictions on the means of notification to the driver; any means may be used, such as sound, light, text, or a combination thereof. By operating the vehicle based on the notification from the operation instruction notification unit 25, the driver can prevent the vehicle from entering a level crossing under abnormal conditions.

[0030] According to the wireless communication system of Embodiment 1, the ground device 10 transmits information about the location of the level crossing along with the conditions within the level crossing to the onboard device 20 of the train. The onboard device 20 determines the operating state that the train should take based on the distance from the train to the level crossing in an abnormal state and notifies the driver. Therefore, for example, even if an abnormality occurs within a level crossing, if the train is far enough away from the crossing that an emergency stop is not necessary, the driver can be instructed to continue normal operation or to slow down. This reduces unnecessary train stops, prevents significant disruptions to the schedule, and alleviates the burden on drivers and passengers.

[0031] Furthermore, if the level crossing, which was in an abnormal state, returns to a normal state, the ground device 10 sends a notification to the on-board device 20 that the condition of the level crossing is now normal. As a result, the on-board device 20 can recognize the situation inside the level crossing in real time and change the operating state that the train should take, which is then notified to the driver. This also helps to reduce unnecessary train stops.

[0032] <Embodiment 2> In Embodiment 1, the distance from the train to the level crossing was calculated from the location information of the level crossing transmitted from the ground device 10 and the location information of the train acquired by the location information acquisition unit 24 of the on-board device 20. In contrast, in Embodiment 2, the on-board device 20 is provided with a database in which the locations of level crossings are pre-stored, eliminating the need for the on-board device 20 to acquire the location information of the level crossings from the ground device 10.

[0033] Figure 3 is a block diagram showing the configuration of the wireless communication system according to Embodiment 2. The configuration of the wireless communication system in Figure 3 is the same as the configuration in Figure 1, but with the addition of a level crossing location database (DB) 26 to the on-board device 20. The level crossing location database 26 is a storage medium that stores identification information (level crossing ID) of level crossings located in various places, linked with their location information. The other configurations are basically the same as in Embodiment 1, so here we will mainly explain the differences from Embodiment 1.

[0034] In Embodiment 1, the level crossing control unit 13 notified the wireless transmission unit 15 of the location information of the level crossing to be controlled and the identification information (level crossing ID) of the level crossing. In Embodiment 2, only the level crossing ID of the level crossing is notified to the wireless transmission unit 15. Furthermore, when the wireless transmission unit 15 receives a notification from the abnormality notification unit 14 indicating the state inside the level crossing (level crossing state notification), it transmits information about the state inside the level crossing (normal or abnormal) and the level crossing ID of the level crossing as a wireless signal from the antenna 16.

[0035] In the on-board device 20, the wireless receiver 21 extracts information on the state of the level crossing and the level crossing ID from the wireless signal transmitted from the ground device 10 and sends it to the operation determination unit 23. The operation determination unit 23 also refers to the level crossing location database 26 and obtains the location information of the level crossing associated with the level crossing ID obtained from the wireless receiver 21. Based on the location information of the level crossing and the location information of the vehicle obtained from the location information acquisition unit 24, it calculates the distance from the vehicle to the level crossing. Then, based on the calculated distance from the vehicle to the level crossing and the state of the level crossing obtained from the wireless receiver 21, the operation determination unit 23 determines the operating state that the vehicle should take (normal operation, slow speed, or stop) and notifies the operation instruction notification unit 25 of the result of that determination.

[0036] Furthermore, if a train approaches a level crossing registered in the level crossing location database 26, but the wireless signal from the ground device 10 that monitors the state of the level crossing is not received by the wireless receiver 21, it is considered that there is some kind of abnormality in the ground device 10 or the onboard device 20. In such cases, the operation determination unit 23 may perform the same processing as when there is an abnormality within the level crossing.

[0037] According to the wireless communication system of Embodiment 2, since the on-board device 20 is equipped with a level crossing location database 26, the ground device 10 does not need to transmit level crossing location information, and the ground device 10 can be simplified.

[0038] Alternatively, the operation determination unit 23 may periodically refer to the location information of the level crossings stored in the level crossing location database 26 and the location information of the vehicle obtained from the location information acquisition unit 24 to determine the location of the next level crossing the vehicle will reach. In this case, the ground device 10 will no longer need to transmit the level crossing ID, and the ground device 10 can be further simplified. However, if the onboard device 20 simultaneously receives wireless signals that do not include the level crossing ID from multiple ground devices 10, it will become impossible to determine which ground device 10 the wireless signal was received from. Therefore, it is assumed that such a situation will not occur (for example, the distance between level crossings will be sufficiently wide, and two or more ground devices 10 will not simultaneously be in a train approach state due to a single train).

[0039] <Embodiment 3> In Embodiments 1 and 2, the operation instruction notification unit 25 of the on-board device 20 only notified the driver of the operating status (normal operation, slow speed, or stop) that the vehicle should be in. In Embodiment 3, the operation instruction notification unit 25 of the on-board device 20 is given a function to notify the level crossing ID of the level crossing where an abnormality has occurred.

[0040] In this embodiment as well, there are no restrictions on the means of notifying the driver. For example, if the operation instruction notification unit 25 displays the crossing ID of the crossing where an abnormality is occurring on the screen, the driver can be shown the crossing IDs of multiple crossings simultaneously if abnormalities are occurring at those crossings. In this case, the crossing IDs of the multiple crossings where abnormalities are occurring may be displayed in order of proximity to the vehicle, and there are no restrictions on the number of crossing IDs to display. Furthermore, even if abnormalities are occurring at multiple crossings, the operation instruction notification unit 25 may notify the driver of only the crossing ID of the nearest crossing where an abnormality is occurring.

[0041] For example, as shown in Figure 4, assume that two level crossings with different level crossing IDs have ground devices 10 (ground device 10A and ground device 10B) installed close to each other, and that the on-board device 20 simultaneously receives wireless signals from ground device 10A and ground device 10B. Note that the on-board device 20 shown in Figure 4 is the same as in Embodiment 2 (Figure 3), but it may also be the same as in Embodiment 1 (Figure 1).

[0042] Ground devices 10A and 10B each enter a train approaching state when a train approaches a monitored level crossing and transmit a radio signal including the conditions inside the level crossing and the level crossing ID. The operation determination unit 23 of the onboard device 20 determines the operating state that the vehicle should take (normal operation, slow speed, or stop) based on the conditions inside each level crossing extracted from the respective radio signals and the distance from the vehicle to each level crossing, and notifies the operation instruction notification unit 25 of the determination result and, if an abnormality has occurred at any of the level crossings, the level crossing ID of that level crossing. The operation instruction notification unit 25 notifies the driver of the operating state that the vehicle should take, the level crossing ID of the level crossing where the abnormality has occurred, and the driver. This allows the driver to recognize which level crossing has an abnormality, reducing the burden on the driver when operating the vehicle.

[0043] Furthermore, the ground device 10 may also transmit information about the nature of any abnormalities occurring within the level crossing (for example, malfunction of barriers or warning devices, presence or absence of obstacles within the level crossing, etc.) in the wireless signal, and the onboard device 20 may acquire this information from the received wireless signal. In that case, the operation instruction notification unit 25 should notify the driver of the operating status that the vehicle should take, the level crossing ID of the level crossing where the abnormality has occurred, and the nature of the abnormality.

[0044] Furthermore, it is possible to freely combine each embodiment, or to modify or omit each embodiment as appropriate.

[0045] The various aspects of this disclosure are summarized below as an appendix.

[0046] (Note 1) A ground device that transmits a wireless signal indicating the status inside the level crossing, An onboard device mounted on the train that receives the aforementioned radio signal, Equipped with, The aforementioned ground equipment is When an abnormality occurs within the level crossing, the wireless signal indicating that the condition within the level crossing is abnormal is transmitted. If there is no abnormality within the level crossing, the wireless signal indicating that the condition within the level crossing is normal is transmitted. The above-mentioned onboard device is, If the received radio signal indicates that the conditions within the level crossing are abnormal, the operating state that the train should take is determined based on the distance from the train to the level crossing. The train driver is notified of the decision regarding the operating conditions the train should take. Wireless communication system.

[0047] (Note 2) The ground device transmits the location information of the level crossing in the wireless signal. The onboard device calculates the distance from the train to the level crossing based on the location information of the level crossing extracted from the received wireless signal. The wireless communication system described in Appendix 1.

[0048] (Note 3) It includes a level crossing location database that stores level crossing identification information and location information of the level crossing linked together. The ground device transmits the identification information of the level crossing in the wireless signal. The onboard device obtains the location information of the level crossing, which is linked to the identification information of the level crossing extracted from the received wireless signal, from the level crossing location database, and calculates the distance from the train to the level crossing based on the location information of the level crossing obtained from the level crossing location database. The wireless communication system described in Appendix 1.

[0049] (Note 4) The ground device transmits the identification information of the level crossing in the wireless signal. The onboard device notifies the train driver of the determination result of the operating state the train should take, along with identification information of the level crossing where an abnormality has occurred, extracted from the received radio signal. A wireless communication system as described in any one of the items from Appendix 1 to Appendix 3.

[0050] (Note 5) The ground device transmits the wireless signal containing information about the nature of the abnormality that occurred within the level crossing. The onboard device notifies the train driver of the result of the determination of the operating state that the train should take, the identification information of the level crossing where the abnormality is occurring, and information on the details of the abnormality extracted from the received radio signal. The wireless communication system described in Appendix 4. [Explanation of Symbols]

[0051] 10, 10A, 10B Ground equipment, 11 Level crossing equipment, 12 Train detection unit, 13 Level crossing control unit, 14 Anomaly notification unit, 15 Wireless transmission unit, 16 Antenna, 151 Transmission signal processing unit, 152 Transmission processing unit, 153 Transmission control unit, 20 Onboard equipment, 21 Wireless reception unit, 22 Antenna, 23 Operation determination unit, 24 Location information acquisition unit, 25 Operation instruction notification unit, 26 Level crossing location database.

Claims

1. A ground device that transmits a wireless signal indicating the state inside a level crossing, An on-vehicle device mounted on a train that receives the wireless signal, Comprising, The ground device, When an abnormality occurs inside the level crossing, transmits the wireless signal indicating that the state inside the level crossing is abnormal, When there is no abnormality inside the level crossing, transmits the wireless signal indicating that the state inside the level crossing is normal, The on-vehicle device, When the received wireless signal indicates that the state inside the level crossing is abnormal, determines the operating state that the train should take based on the distance from the train to the level crossing, Notifies the outside of the determination result of the operating state that the train should take, A wireless communication system.

2. The ground device includes the position information of the level crossing in the wireless signal and transmits it, The on-vehicle device calculates the distance from the train to the level crossing based on the position information of the level crossing extracted from the received wireless signal, The wireless communication system according to claim 1.

3. Comprising a level crossing position database that stores and associates the identification information of the level crossing with the position information of the level crossing, The ground device includes the identification information of the level crossing in the wireless signal and transmits it, The on-vehicle device acquires the position information of the level crossing associated with the identification information of the level crossing extracted from the received wireless signal from the level crossing position database, and calculates the distance from the train to the level crossing based on the position information of the level crossing acquired from the level crossing position database, The wireless communication system according to claim 1.

4. The ground device includes the identification information of the level crossing in the wireless signal and transmits it, The on-vehicle device notifies the outside of the identification information of the level crossing where an abnormality has occurred extracted from the received wireless signal, together with the determination result of the operating state that the train should take, The wireless communication system according to any one of claims 1 to 3.

5. The ground device includes information on the content of the abnormality that has occurred inside the level crossing in the wireless signal and transmits it, The on-vehicle device notifies the outside of the information on the content of the abnormality extracted from the received wireless signal, together with the determination result of the operating state that the train should take and the identification information of the level crossing where an abnormality has occurred, The wireless communication system according to claim 4.

6. An on-vehicle device mounted on a train that receives a wireless signal indicating the state inside a level crossing transmitted from a ground device, When the received wireless signal indicates that the state inside the level crossing is abnormal, based on the distance from the train to the level crossing, determine the operating state that the train should take, Notify the outside of the determination result of the operating state that the train should take, On-vehicle device.

7. Calculate the distance from the train to the level crossing based on the position information of the level crossing extracted from the received wireless signal. The on-vehicle device according to claim 6.

8. It is provided with a level crossing position database that associates and stores the identification information of the level crossing and the position information of the level crossing, Obtain the position information of the level crossing associated with the identification information of the level crossing extracted from the received wireless signal from the level crossing position database, and calculate the distance from the train to the level crossing based on the position information of the level crossing obtained from the level crossing position database. The on-vehicle device according to claim 6.

9. Notify the outside of the identification information of the level crossing where the abnormality has occurred, which is extracted from the received wireless signal, together with the determination result of the operating state that the train should take. The on-vehicle device according to any one of claims 6 to 8.

10. Notify the outside of the information on the content of the abnormality extracted from the received wireless signal, together with the determination result of the operating state that the train should take and the identification information of the level crossing where the abnormality has occurred. The on-vehicle device according to claim 9.

11. A ground device that transmits a wireless signal indicating the state inside the level crossing, When an abnormality occurs inside the level crossing, transmit the wireless signal indicating that the state inside the level crossing is abnormal, When there is no abnormality inside the level crossing, transmit the wireless signal indicating that the state inside the level crossing is normal, Transmit the position information of the level crossing or the identification information of the level crossing included in the wireless signal. Ground device.

12. Transmit the information on the content of the abnormality that has occurred inside the level crossing included in the wireless signal. The ground device according to claim 11.

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