JP6480884B2 - Ground system - Google Patents

Description

  The present invention relates to a ground system that performs wireless communication with an on-train device of a train.

  In recent years, in railways, development of train control systems using wireless communication as a means of communication between the vehicle and the ground has progressed. Compared with wired communication, wireless communication has a merit that the cost for installation and maintenance of ground facilities can be greatly reduced (see, for example, Patent Document 1).

JP2015-139205A

  However, compared with wired communication, wireless communication is liable to cause communication failures such as communication delays and communication interruptions, and has a drawback in that communication reliability is inferior. In railways, since safe driving of trains is the most important, when using wireless communication, it is common to construct a dedicated wireless communication network. In order to build a dedicated wireless communication network, it is necessary to install a dedicated wireless base station along the track. However, it is necessary to install and maintain a dedicated wireless base station in a quiet line area where the number of trains is small. Cost burden is large.

  Therefore, a method for constructing a communication system at a relatively low cost by utilizing a frequency band that can be used by the public, such as a public wireless LAN, for wireless communication between the vehicle and the ground, is considered. It is done. However, since the frequency band that can be used by the public is shared with other users, there may be interference and interference due to communication by other users, and communication delays may occur depending on the usage situation. Less reliable than communication networks.

  The present invention has been made in view of the above circumstances, and the object of the present invention is to improve the reliability when used for radio communication for train control using a frequency band that can be used by the public. It is to realize a technology that can be achieved.

The first invention for solving the above-described problems is
A ground system that communicates wirelessly with on-train equipment of a train,
A wireless communication device installed so as to include the station premises in a communicable range corresponding to each station premises,
A measuring device that is installed in each station premises and measures the electric field strength for each communication channel within the frequency band in the station premises,
A ground control device that determines a communication channel used by the wireless communication device and controls communication with the on-vehicle device via the wireless communication device;
Comprising
The ground control device is:
When the train stopped at the first station travels to the second station, which is the next station, based on the measurement results of the measurement devices at the first station and the second station, the first station and the second station Determining means for determining a communication channel used by the wireless communication devices at two stations;
On-board change control means for notifying the on-board device of the determined communication channel and setting a communication channel for performing wireless communication with the wireless communication device at the first station and the wireless communication device at the second station; ,
Means for setting a communication channel used by the wireless communication devices of the first station and the second station to the determined communication channel;
Comprising
It is a ground system.

  According to the first aspect of the present invention, the communication channel used when the train stopped at the first station travels to the second station, which is the next station, is an electric field for each communication channel at the first station and the second station. Determined based on intensity. If the wireless communication is wireless communication in a frequency band that can be used by the public shared with other users, then the measured electric field strength changes depending on the usage status of the place. For this reason, the reliability of wireless communication used for train control can be determined by selecting and determining, for example, the communication channel with the lowest electric field strength from the plurality of available communication channels based on the electric field strength for each communication channel. It becomes possible to improve the property.

As a second invention, the ground system of the first invention,
The determination means preferentially determines a communication channel having a smaller electric field strength as a communication channel to be used as a result of measurement by the measurement device at the time of determination.
A ground system may be configured.

  According to the second aspect of the invention, it is determined to preferentially use a communication channel having a smaller electric field strength. In other words, the use of a communication channel means that a radio signal of the communication channel is being transmitted, and the electric field strength of the communication channel increases (stronger) as the amount of communication data increases. . For this reason, it is possible to realize highly reliable wireless communication by using a communication channel having a smaller (weak) electric field strength.

As a third invention, the ground system of the first or second invention,
The wireless communication devices of the first station and the second station are installed so that the communicable ranges do not overlap,
The determining means determines that the wireless communication devices at the first station and the second station use the same communication channel.
A ground system may be configured.

  According to the third aspect of the invention, when the wireless communication devices at the first station and the second station are installed so that the respective communicable ranges do not overlap, no interference occurs even if the same communication channel is used. Therefore, the wireless communication devices at the first station and the second station can use the same communication channel. By using the same communication channel, it is not necessary to change the communication channel to be used in the on-board device. Therefore, it is not necessary to switch the communication channel from the departure from the first station until the arrival at the second station.

As a fourth invention, the ground system of the first or second invention,
The wireless communication devices of the first station and the second station are installed so that the communicable ranges partially overlap,
The determining means determines that the wireless communication devices of the first station and the second station use different communication channels,
The on-board change control means notifies the on-board device of the determined communication channel, and communicates with the wireless communication device at the first station, and the wireless communication device at the second station. To set the communication channel when communicating with
A ground system may be configured.

  According to the fourth aspect of the present invention, when the wireless communication devices at the first station and the second station are installed so that their respective communicable ranges partially overlap, different communication channels are used to avoid interference. I will use it.

As a fifth invention, the ground system of the first or second invention,
The communicable range is installed at an intermediate point between the first station and the second station so that the communicable range partially overlaps the communicable range of each of the wireless communication devices at the first station and the second station. A wireless communication device for intermediate points,
A measuring device for an intermediate point that measures the electric field strength for each communication channel in the frequency band at the intermediate point;
Further comprising
The determination means is configured to determine the radio of the first station and the second station based on a measurement result of the measurement device at the first station and the second station and a measurement result of the measurement device for the intermediate point. A communication device and a communication channel used by the wireless communication device for the intermediate point are determined to be different communication channels;
The on-vehicle change control means notifies the on-board device of the determined communication channel, and communicates with the wireless communication device of the first station, and the wireless communication device for the intermediate point, Setting a communication channel when communicating and a communication channel when communicating with the wireless communication device of the second station,
A ground system may be configured.

  According to the fifth aspect of the invention, the intermediate point wireless communication device is partially connected to the wireless communication devices of the first station and the second station at the intermediate point between the first station and the second station. In the case of overlapping installations, different communication channels are used to avoid interference.

The block diagram of a ground system. Explanatory drawing of the setting of the communication channel in 1st Example. The function block diagram of the central apparatus and station control apparatus in 1st Example. The data structural example of 1st radio | wireless communication apparatus information. The data structural example of usable frequency information. Data configuration example of radio wave environment information. The data structural example of frequency allocation information. The data structural example of frequency use information. The flowchart of the process regarding the radio | wireless communication in 1st Example. Explanatory drawing of the setting of the communication channel in 2nd Example. The function block diagram of the central apparatus in 2nd Example. The data structural example of 2nd radio | wireless communication apparatus information. The flowchart of the process regarding the radio | wireless communication in 2nd Example. An example of installing a wireless communication device at an intermediate point between stations. Explanatory drawing of the setting of a communication channel when a radio | wireless communication apparatus is installed in the intermediate point between stations.

[System configuration]
FIG. 1 is a configuration diagram of a ground system 1 in the present embodiment. The ground system 1 is a system for performing wireless communication with the on-board device 70 mounted on the train 60 traveling on the rail R, and is installed corresponding to the central device 10 that is a ground control device and each station. The wireless communication device 20 includes a measurement device 30 and a station control device 40. In each station, the wireless communication device 20 and the measurement device 30 and the station control device 40 are connected to communicate with each other so that information can be input and output. Further, the station control device 40 of each station and the central device 10 are communicably connected via a dedicated line.

  Wireless communication between the ground system 1 and the on-board device 70 is performed by wireless communication using a frequency band that can be used by the public, and uses any one of a plurality of communication channels defined in the frequency band. To communicate.

  The wireless communication device 20 is installed so as to include the corresponding station premises within the communicable range, and performs wireless communication with the on-board device 70 of the train 60 within the communicable range according to the control of the station control device 40. Wireless communication between the wireless communication device 20 and the on-board device 70 is performed using a communication channel notified from the central device 10 via the central device 10 among a plurality of available communication channels.

  The measuring device 30 measures the electric field strength for each communication channel in the corresponding station premises. This measurement is performed as needed, and the measurement result is output to the central device 10 via the station control device 40.

  The station control device 40 controls the wireless communication device 20 to transmit information input from the central device 10 to the on-board device 70 via the wireless communication device 20 or on-vehicle device via the wireless communication device 20. The wireless communication with the on-board device 70 such as outputting the information received from the central device 10 to the central device 10 is controlled. In addition, the measurement result of the electric field intensity output from the measuring device 30 is output to the central device 10.

  The central device 10 determines a communication channel to be used for wireless communication between the wireless communication device 20 and the on-board device 70 based on the measurement result of the electric field strength for each communication channel of each station acquired from the station control device 40. Then, the determined communication channel is notified to the on-board device 70 via the station control device 40 and set as a communication channel to be used, and the communication channel to be used by the wireless communication device 20 is determined. To change.

  Hereinafter, in the ground system 1 configured as described above, two embodiments relating to determination of a communication channel used for wireless communication between the wireless communication device 20 and the on-board device 70 will be described.

[First embodiment]
The first embodiment is an embodiment in which the wireless communication devices 20 at adjacent stations are installed so that their communicable ranges do not overlap.

<Overview>
FIG. 2 is a diagram illustrating a method for determining a communication channel used for wireless communication between the wireless communication device 20 and the on-board device 70 in the first embodiment. FIG. 2 shows an example of a communication channel used when a train 60 that has entered the A station that is the first station travels to the B station of the next station that is the second station after stopping at the A station. Yes. At station A, a wireless communication device 20a including the station A within the communicable range 22a is installed, and at station B, a wireless communication device 20b including the station B within the communicable range 22b is installed, At the C station, a wireless communication device 20c including the C station premises within the communicable range 22c is installed.

  First, as shown in FIG. 2A, when the train 60 enters the station A, the on-board device 70 of the train 60 and the wireless communication device 20a perform wireless communication using a communication channel having a frequency f1. Next, as shown in FIG. 2 (b), when the train 60 stops at the A station, the communication channel used when traveling to the next B station is determined as the frequency f2, and the radio communication device 20a is connected to the on-board device. The on-board device 70 changes the communication channel used in the wireless communication with the wireless communication device 20 from the frequency f1 to the frequency f2 while changing the communication channel used in the wireless communication with the wireless communication device 70 from the frequency f1. As a result, the communication channel used for wireless communication between the on-board device 70 and the wireless communication device 20a is changed from the frequency f1 to the frequency f2. As described above, the first embodiment is characterized in that communication channels having the same frequency are used in the wireless communication devices 20a and 20b at the stations A and B, respectively.

  The communication channel used when traveling to the next station is determined by the central apparatus 10 based on the electric field strength for each communication channel at station A and the electric field strength for each communication channel at station B. Specifically, communication channels with smaller (weak) electric field strengths at both stations are preferentially selected, such as selecting communication channels where the electric field strengths at both stations A and B satisfy predetermined low-intensity conditions. Decide to choose.

  The electric field strength at each station is measured by the measuring device 30 installed in the corresponding station premises. In order to use a frequency band that can be used by the public, the electric field strength of each communication channel may change depending on the location. The measuring device 30 measures the radio wave condition used in the environment without emitting radio waves. Therefore, as a communication channel to be used while the train 60 travels from the A station to the B station, an appropriate communication channel according to the radio wave condition at that location can be set. That is, by preferentially selecting a communication channel with a smaller electric field strength based on the measurement result of the measuring device 30, the communication channel that is presumed to be least used by other users is designated as wireless communication for train control. And reliability of radio communication for train control can be improved.

  While the train 60 leaves the A station and travels outside the communicable ranges 22a and 22b of the wireless communication devices 20a and 20b between the A station and the B station, the on-board device 70 and the wireless communication device 20a. , 20b is not performed. As shown in FIG. 2C, when the train 60 enters the B station, wireless communication using the communication channel of the frequency f2 is started between the on-board device 70 and the wireless communication device 20b. Thereafter, as shown in FIG. 2 (d), when the train 60 stops at the B station, similarly, it is the next station based on the electric field strength for each communication channel at both the B station and the next station C station. The communication channel used when traveling to station C is determined as the frequency f3, and the communication channel used in the wireless communication between the on-board device 70 and the wireless communication device 20b is changed from the frequency f2 to the frequency f3.

<Functional configuration>
FIG. 3 is a functional configuration diagram of the central device 10A and the station control device 40 in the first embodiment. According to FIG. 3, the central device 10A is a computer configured to include an operation unit 102, a display unit 104, a sound output unit 106, a communication unit 108, a processing unit 200A, and a storage unit 300A. .

  The operation unit 102 is realized by an input device such as an operation button, a switch, or a touch panel, for example, and outputs an operation signal corresponding to the performed operation to the processing unit 200A. The display unit 104 is realized by a display device such as a liquid crystal display or a display lamp, and performs various displays based on display signals from the processing unit 200A. The sound output unit 106 is realized by a sound output device such as a speaker, for example, and outputs various sounds based on the sound signal from the processing unit 200A. The communication unit 108 is connected to a dedicated line and inputs / outputs information to / from the station control device 40.

  The processing unit 200A includes an arithmetic device such as a CPU, for example, and performs overall control of the central device 10A based on programs, data, and the like stored in the storage unit 300A. In addition, the processing unit 200A executes various arithmetic processes in accordance with the first central control program 302 stored in the storage unit 300A, whereby the standing line management unit 202, the radio wave environment management unit 204, the first assigned frequency determination unit 206, It functions as a first on-vehicle change control unit 208 and a first ground change control unit 210.

  Information regarding the wireless communication device 20 installed at each station is stored as first wireless communication device information 304. FIG. 4 is an example of the data configuration of the first wireless communication apparatus information 304. According to FIG. 4, the first wireless communication device information 304 is stored for each station 304a in association with the wireless communication device 304b installed at the station, its installation position 304c, and the communicable range 304d. doing. The installation position 304c is a position indicated by a distance along a track from a predetermined starting point such as a kilometer.

  In the wireless communication between the ground system 1 and the on-board device 70, a plurality of communication channels can be used, and usable frequencies are stored as usable frequency information 308. FIG. 5 is an example of the data configuration of the usable frequency information 308. According to FIG. 5, the usable frequency information 308 stores a frequency 308b that can be used as a communication channel in association with each station 308a.

  The standing line management unit 202 manages the current position and speed of each train 60. The position and speed of the train 60 are obtained by wireless communication via the wireless communication device 20 based on the position and speed of the own train calculated by the on-board device 70 based on the count value of the number of rotations of the axle detected by the speed generator. Or may be acquired as a detection result of a track circuit configured by dividing a track. The acquired current position and speed of each train 60 are stored as standing line information 306.

  The radio wave environment management unit 204 manages the current field strength for each communication channel at each station. The current electric field strength of each station is acquired as a measurement result of the electric field strength by the measuring device 30 input from the station control device 40.

  The acquired current electric field strength of each station is stored as radio wave environment information 310. FIG. 6 is an example of the data configuration of the radio wave environment information 310. According to FIG. 6, the radio wave environment information 310 stores the electric field intensity 310c of each frequency 310b that can be used as a communication channel in association with each station 310a.

  The first assigned frequency determination unit 206 determines the frequency of the communication channel that the on-board device 70 of the train 60 uses for wireless communication with the wireless communication device 20 when the train 60 stopped at the station travels to the next station. decide. Specifically, based on the electric field strength for each communication channel at the station (first station) where the train 60 is stopped and the electric field strength for each communication channel at the next station (second station), wireless communication at the station being stationed is performed. The frequency of the communication channel to be used is determined by using the communication channel of the same frequency in the wireless communication with the device 20 and the wireless communication device 20 of the next station.

  In each station, there are a plurality of communication channel frequencies that can be used for wireless communication (see FIG. 5), and different trains 60 can be assigned to the respective frequencies. That is, the first assigned frequency determination unit 206 refers to the radio wave environment information 310 and the frequency assignment information 312 and, for example, has a low electric field strength from the frequencies to which no train is assigned at both the station at the station and the next station. The frequency is determined as the frequency assigned to the target train 60. The electric field strength for each communication channel at the station in line and the next station can be acquired from the radio wave environment information 310.

  The determined frequency of the communication channel is stored as frequency allocation information 312. FIG. 7 is an example of the data configuration of the frequency allocation information 312. According to FIG. 7, the frequency allocation information 312 stores, for each station 312a, a train 312c that is allocated to use a communication channel of the frequency for each usable frequency 312b in association with each other.

  The first on-board change control unit 208 notifies the corresponding on-board device 70 of the frequency of the communication channel determined by the first assigned frequency determination unit 206, and determines the communication channel used when traveling to the next station. The frequency is set to the determined frequency. Notification to the on-board device 70 can be performed via the wireless communication device 20 at the station where the corresponding train 60 is located.

  The first ground change control unit 210 notifies the frequency of the communication channel determined by the first allocated frequency determination unit 206 to the station where the corresponding train 60 is located and the radio communication device 20 of the next station, respectively. The frequency used for the wireless communication with the on-board device 70 is set.

  The storage unit 300A is realized by a storage device such as a ROM, a RAM, and a hard disk, for example. The storage unit 200A stores a system program and data for the integrated control of the central device 10, and the processing unit 200A. Used as a work area, the calculation result executed by the processing unit 200A, input data via the communication unit 108, and the like are temporarily stored. Further, the storage unit 300A stores a first central control program 302, first wireless communication device information 304, standing line information 306, usable frequency information 308, radio wave environment information 310, and frequency allocation information 312. Is done.

  The station control device 40 is a computer including an operation unit 502, a display unit 504, a sound output unit 506, a communication unit 508, a processing unit 600, and a storage unit 700.

  The operation unit 502 is realized by an input device such as an operation button, a switch, or a touch panel, for example, and outputs an operation signal corresponding to the performed operation to the processing unit 600. The display unit 504 is realized by a display device such as a liquid crystal display or a display lamp, and performs various displays based on display signals from the processing unit 600. The sound output unit 506 is realized by a sound output device such as a speaker, for example, and outputs various sounds based on the sound signal from the processing unit 600. The communication unit 508 inputs and outputs information with the central apparatus 10 by connecting to a dedicated line.

  The processing unit 600 is configured to include an arithmetic device such as a CPU, for example, and performs overall control of the station control device 40 based on programs, data, and the like stored in the storage unit 700. The processing unit 600 also functions as a radio wave environment notification control unit 602, a use frequency setting unit 604, and a wireless communication control unit 606 by executing various arithmetic processes according to the station control program 702 stored in the storage unit 700. .

  The radio wave environment notification control unit 602 outputs the measurement value of the electric field strength for each communication channel input from the measurement device 30 to the central device 10.

  The use frequency setting unit 604 sets the communication channel of the frequency notified from the central device 10 as a communication channel used in wireless communication with the on-board device 70 of the corresponding train. There are a plurality of communication channel frequencies that can be used for wireless communication with the on-board device 70, and the setting of the communication channel used for wireless communication with the on-board device 70 at the station where the station control device 40 is installed is as follows. It is stored as frequency usage information 704.

  FIG. 8 is an example of the data configuration of the frequency usage information 704. According to FIG. 8, the frequency use information 704 stores the train 704b assigned to use the frequency in association with each frequency 704a of the communication channel that can be used by the radio communication device 20 of the station. .

  The wireless communication control unit 606 controls wireless communication with the on-board device 70 via the wireless communication device 20. At this time, with reference to the frequency use information 704, the radio communication device 20 is controlled to perform radio communication using a communication channel having a frequency assigned to the corresponding train 60.

  The storage unit 700 is realized by a storage device such as a ROM, a RAM, or a hard disk, for example. The processing unit 600 stores a system program and data for the integrated control of the station control device 40, and the processing unit 600. The calculation result executed by the processing unit 600, input data via the communication unit 508, and the like are temporarily stored. The storage unit 700 stores a station control program 702 and frequency use information 704.

<Process flow>
FIG. 9 is a flowchart illustrating the wireless communication process in the first embodiment. FIG. 9 illustrates processing related to wireless communication between the on-board device 70 of the target train and the ground system 1 during a period from when the target train enters the target station until the vehicle advances. In addition, the processing of the central device 10, the station control device 40 of the target station, and the on-board device 70 of the target train is illustrated in order from the left.

  First, when the target train enters the target station and enters the communicable range of the target station wireless communication device 20 (step C1), the on-board device 70 of the target train and the target station wireless communication device 20 are connected. Wireless communication with the station control device 40 is started. In the central apparatus 10, the station management unit 202 manages the position of the target train, and when detecting that the target train stops at the station (step A <b> 1), the first allocated frequency determination unit 206 includes the target station, and Based on the electric field strength of each communication channel at the next station of the target station, the frequency of the communication channel used when the target train travels to the next station is determined (step A3).

  Next, the first on-board change control unit 208 notifies the determined frequency of the communication channel to the on-board device 70 of the target train by wireless communication via the station control device 40 of the target station (step A5). Then, the on-board device 70 of the target train changes the frequency used for wireless communication to the notified frequency (step C5).

  Moreover, in the central apparatus 10, the 1st ground change control part 210 notifies the frequency of the determined communication channel to the station control apparatus 40 of an object station and a next station (step A7). Then, in the station control device 40 of the target station, the use frequency setting unit 604 uses the frequency of the communication channel notified from the central device 10 as the frequency of the communication channel used for wireless communication with the on-board device 70 of the target train. Set (step B1). Thereby, the frequency of the communication channel used for the radio | wireless communication with the station control apparatus 40 of an object station and an object train is switched. Similarly, in the station control device 40 at the next station, the use frequency setting unit 604 sets the frequency of the communication channel notified from the central device 10 as a communication channel used for wireless communication with the target train (step). D1).

  Moreover, in the central apparatus 10, the 1st ground change control part 210 notifies the completion | finish of the allocation of the communication channel to a target train to the station control apparatus 40 of a front station (station in front of a target station) (step A9). . Then, in the station control device 40 at the previous station, the use frequency setting unit 604 ends the assignment of the communication channel to the target train in accordance with the notification from the central device 10 (step D3).

  Thereafter, when the target train departs (step C7), moves into the target station (step C9), and moves out of the communicable range of the wireless communication device 20 of the target station, the target train car upper device 70 and the target station Wireless communication with the station control device 40 ends.

[Second Embodiment]
The second embodiment is an example in which the wireless communication devices 20 at adjacent stations are installed such that their communicable ranges partially overlap. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted or simplified.

<Overview>
FIG. 10 is a diagram illustrating a method for determining a communication channel used for wireless communication between the wireless communication device 20 and the on-board device 70 in the second embodiment. FIG. 10 shows an example of a communication channel used when a train 60 that has entered the D station, which is the first station, travels to the E station of the next station, which is the second station, after stopping at the D station. Yes. A wireless communication device 20d including the D station premises within the communicable range 22d is installed at the D station, and a wireless communication device 20e including the E station premises within the communicable range 22e is installed at the E station. Further, the communicable range 22d of the wireless communication device 20d and the communicable range 22e of the wireless communication device 20e partially overlap between the A station and the B station, and form an overlapping range 24.

  First, as shown in FIG. 10A, when the train 60 enters the D station, the on-board device 70 and the radio communication device 20d of the train 60 perform radio communication using a communication channel having a frequency f4. Next, as shown in FIG. 10B, when the train 60 stops at the D station, the frequency f5 is used from the D station to the overlapping range 24 as a communication channel used when traveling to the next E station. From the overlap range 24 to the E station, it is determined that the frequency f6 is used. In this way, in the second embodiment, communication channels having different frequencies in the wireless communication devices 20d and 20e at the D station and the E station, respectively, with the overlapping range 24 of the communicable ranges 22d and 22e between the D station and the E station as a boundary. It is characterized by using. That is, a communication channel with a different frequency is used when a certain station advances and when the next station enters.

  The wireless communication device 20d changes the communication channel used for wireless communication with the on-vehicle device 70 from the frequency f4 to the frequency f5, and the on-vehicle device 70 uses communication for wireless communication with the wireless communication device 20d. The channel is changed from frequency f4 to frequency f5. As a result, the communication channel used in the wireless communication between the on-board device 70 and the wireless communication device 20d is changed from the frequency f4 to the frequency f5. In addition, the radio communication device 20e associated with station E sets a communication channel having a frequency f6 as a communication channel used for radio communication with the on-board device 70.

  Here, the communication channel used when traveling from the D station to the E station is determined by the central device 10 based on the electric field strength for each communication channel of the D station and the electric field strength for each communication channel of the E station. Is done. Specifically, the frequency of the communication channel used for wireless communication between the on-board device 70 and the wireless communication device 20d is determined based on the electric field strength for each communication channel at the D station, and Based on the electric field strength, a frequency to be used for wireless communication between the on-board device 70 and the wireless communication device 20e is determined.

  The electric field strength at each station is measured by the measuring device 30 installed in the corresponding station premises. In order to use a frequency band that can be used by the public, the electric field strength of each communication channel may change depending on the location. In this respect, the second embodiment is the same as the first embodiment. The measuring device 30 measures the radio wave condition used in the environment without emitting radio waves. Therefore, as a communication channel to be used while the train 60 travels from the D station to the E station, an appropriate communication channel according to the radio wave condition at that location can be set. For example, by preferentially selecting a communication channel with a smaller electric field strength, a communication channel that is presumed to be least used by other users can be used for train control wireless communication. The reliability of wireless communication can be improved.

  Subsequently, as shown in FIG. 10C, when the train 60 departs from the station D and reaches the overlapping range 24 of the communicable ranges 22d and 22e, the on-board device 70 selects a communication channel used for wireless communication. The frequency f5 is changed to the frequency f6. Thereby, the wireless communication between the on-board device 70 and the wireless communication device 20d is terminated, and the wireless communication between the on-board device 70 and the wireless communication device 20e is started.

  Thereafter, as shown in FIG. 10D, when the train 60 stops at the E station, the frequency channel used in the section to the next F station is determined in the same manner.

<Functional configuration>
FIG. 11 is a functional configuration diagram of the central device 10B in the second embodiment. The station control device 40 has the same functional configuration as that of the first embodiment.

  According to FIG. 11, in central apparatus 10B, processing unit 200B executes various arithmetic processes according to second central control program 314 stored in storage unit 300B, so that in-line management unit 202 and radio wave environment management unit 204 are executed. , Function as a second allocated frequency determination unit 212, a second on-vehicle change control unit 214, and a second ground change control unit 216.

  The second assigned frequency determination unit 212 determines the frequency of the communication channel that the on-board device 70 of the train 60 uses for wireless communication with the wireless communication device 20 when the train 60 stopped at the station travels to the next station. decide. Specifically, using different communication channels at the station at the next station and using the communication channel at the station at the next station based on the electric field strength for each communication channel of the station at the current station (that is, at the station at the current station) The communication channel to be used is determined) and the communication channel to be used for wireless communication with the wireless communication device 20 at the next station (that is, at the time of the next station entry) is determined based on the electric field strength of each communication channel at the next station. Determine the frequency.

  Further, with reference to the second wireless communication device information 316, for example, along a track in the overlapping range of the communicable range of the wireless communication device 20 at the station in line and the communicable range of the wireless communication device 20 at the next station. The center position is determined as the switching position of the frequency used for wireless communication. The determined frequency of the communication channel is stored as frequency allocation information 312.

  The second on-vehicle change control unit 214 determines the frequency of the communication channel used by the second assigned frequency determination unit 212 at the time of advancement of the station in line and at the time of entry of the next station together with the frequency switching position. Then, the corresponding on-board device 70 is notified and set to the frequency of the communication channel used at the time of advancing from the station on the line.

  FIG. 12 is an example of the data configuration of the second wireless communication apparatus information 316. According to FIG. 12, the second wireless communication device information 316 includes, for each station 316a, a wireless communication device 316b installed at the station, its installation position 316c, a communicable range 316d, and a communicable range 316d. Among these, an overlapping range 316e with a communicable range of another adjacent wireless communication device 20 is stored in association with each other.

  The second ground change control unit 216 notifies the radio communication device 20 of the park station of the frequency used when the station is stationed, determined by the second allocation frequency determination unit 212, and uses the frequency used when the next station enters the station. Notification is made to the radio communication device 20 at the next station, and the frequency used for radio communication with the on-board device 70 is set.

  In the central apparatus 10B, the storage unit 300B has a second central control program 314, second wireless communication apparatus information 316, standing line information 306, usable frequency information 308, radio wave environment information 310, and frequency allocation information 312. Is memorized.

<Process flow>
FIG. 13 is a flowchart for explaining a wireless communication process in the second embodiment. FIG. 13 illustrates processing related to wireless communication between the on-board device 70 of the target train and the ground system 1 during a period from when the target train enters the target station until the vehicle moves out. In addition, the processing of the central device 10, the station control device 40 of the target station, and the on-board device 70 of the target train is illustrated in order from the left.

  First, the target train is performing wireless communication with the wireless communication device 20 of the target station to enter, and after entering the target station (step C1), the target train stops at a predetermined stop position (step C3). In the central apparatus 10, the station management unit 202 manages the position of the target train, and when detecting that the target train stops at the station (step A <b> 1), the second allocated frequency determination unit 212 determines that the target train is the next station. The frequency of the communication channel to be used when traveling up to is determined. That is, based on the field strength of each target station communication channel, determine the frequency of the communication channel used when the target train advances the target station, based on the field strength of each communication channel of the next station of the target station, Determine the frequency of the communication channel used when entering the next station. Further, for example, the center position along the track in the overlapping range of the communicable range of the wireless communication device 20 at each of the target station and the next station is determined as the switching position of the frequency used for wireless communication (step A11). .

  Next, the second vehicle on-board change control unit 214 sets the frequency of the communication channel determined to be used when entering the next station and when entering the next station, together with the frequency switching position, the station control device 40 of the target station. Notification is made to the on-board device 70 of the target train through wireless communication (step A13). Then, the on-board device 70 of the target train changes the frequency used for wireless communication to the frequency notified to be used when the target station advances (step C5).

  Further, in the central device 10, the second ground change control unit 216 notifies the station control device 40 of the target station of the frequency of the communication channel determined to be used when the target station advances, and is used when the next station enters. The determined frequency is notified to the station control device 40 of the next station (step A15). Then, in the station control device 40 of the target station, the use frequency setting unit 604 uses the frequency of the communication channel notified from the central device 10 as the frequency of the communication channel used for wireless communication with the on-board device 70 of the target train. Set (step B1). Thereby, the frequency of the communication channel used for the radio | wireless communication with the station control apparatus 40 of an object station and an object train is switched. Similarly, in the station control device 40 at the next station, the use frequency setting unit 604 sets the frequency of the communication channel notified from the central device 10 as a communication channel used for wireless communication with the target train (step). D1).

  In the station control device 40, the second ground change control unit 216 notifies the station control device 40 at the previous station of the end of assignment of the communication channel to the target train (step A9). Then, in the station control device 40 at the previous station, the use frequency setting unit 604 ends the assignment of the communication channel to the target train in accordance with the notification from the central device 10 (step D3).

  Thereafter, the target train departs (step C7), and advances to the target station (step C9). When the on-board device 70 of the target train reaches the frequency switching position (step C9: YES), the on-board device 70 changes the frequency of the communication channel used for wireless communication to the frequency notified to be used when entering the next station ( Step C13). That is, the target train ends wireless communication with the wireless communication device 20 at the target station and starts wireless communication with the wireless communication device 20 at the next station.

[Function and effect]
Thus, according to the ground system 1 of this embodiment, it is possible to improve the reliability of radio communication for train control using a frequency band that can be used by the public. That is, in the ground system 1, the central device 10 determines a communication channel to be used when the train 60 stopped at the station travels to the next station based on the electric field strength for each communication channel at the stop station and the next station. Then, the determined frequency is notified to the radio communication device 20 of each stop station and the next station, and to the on-board device 70 of the train 60.

  Radio communication in a frequency band that can be used by the public is shared with other users, and at that time, the measured electric field strength varies depending on the usage situation of the place. For this reason, it is possible to select a communication channel with a smaller (weak) electric field strength from communication channels having a plurality of frequencies that can be used, and determine the communication channel to be used as a reliable wireless communication in train control applications. Can be realized.

  As in the first embodiment, when the communicable ranges 22 of the wireless communication devices 20 at adjacent stations are not overlapped, interference does not occur, so the same communication channel is set at the adjacent station. Can be used. Further, as in the second embodiment, when the communicable ranges 22 of the wireless communication devices 20 of adjacent stations are partially overlapped, in order to avoid interference, Use a different communication channel.

[Modification]
It should be noted that embodiments to which the present invention can be applied are not limited to the above-described embodiments, and can of course be changed as appropriate without departing from the spirit of the present invention.

(A) Installing a wireless communication device at an intermediate point The wireless communication device 20 may be installed at an intermediate point between stations. FIG. 14 is an example of installation of the wireless communication device 20 at an intermediate point between stations. As shown in FIG. 14, the intermediate point control device 42 corresponding to the wireless communication device 20 for the intermediate point, the measuring device 30, and the station control device 40 is provided at the intermediate point between the stations along the track, similarly to each station. Is installed. The measuring device 30 for the intermediate point measures the electric field strength for each communication channel at the intermediate point. The wireless communication device 20 and the measuring device 30 are connected to the intermediate point control device 42 so as to be able to input and output information. The intermediate point control device 42 is connected to the central device 10 so as to be able to communicate with each other through a dedicated line. Has been.

  As shown in FIG. 15, the wireless communication device 20 for the intermediate point is installed such that the communicable range 22 partially overlaps the communicable range 22 of the wireless communication device 20 of each of the two adjacent stations. ing. FIG. 15 shows an example in which a wireless communication device 20h is installed at an intermediate point between the F station and the G station. At station F, a wireless communication device 20f including F station within the communicable range 22f is installed, and at station G, a wireless communication device 20g including G station within the communicable range 22g is installed. A wireless communication device 20h for an intermediate point is installed at an intermediate point with the station. The communicable range 22h of the wireless communication device 20h for the intermediate point is partially overlapped with the communicable range 22d of the wireless communication device 20d on the F station side to form an overlapping range 24f, and the wireless communication device 20g on the G station side. An overlapping range 24g is formed partially overlapping with the communicable range 22g.

  Then, the central device 10 determines a communication channel to be used when the train 60 stopped at the F station travels to the next G station. That is, based on the electric field strength for each communication channel at station F, the frequency of the communication channel used for wireless communication with the wireless communication device 20f (that is, used when advancing from station F) is determined. Based on the electric field strength for each communication channel, the frequency of the communication channel used for wireless communication with the wireless communication device 20h (that is, used when passing through the intermediate point) is determined, and the electric field for each communication channel at the G station is determined. Based on the strength, the frequency of the communication channel used for wireless communication with the wireless communication device 20g (that is, used when entering the G station) is determined.

  Then, the determined frequency is notified to each of the wireless communication devices 20f, 20g, and 20h, and is also notified to the on-board device 70 of the train 60 together with the switching positions 26f and 26g determined within the respective overlapping ranges 24f and 24g. Is done. The on-board device 70 changes the frequency of the communication channel to the frequency notified to be used when advancing at the F station, starts radio communication with the radio communication device 20f, and the train 60 enters the F station. After that, every time the switching position 26 is reached, the frequency is changed to the notified frequency. That is, when reaching the switching position 26f, the frequency is changed to the frequency notified to be used when traveling at the intermediate point, wireless communication with the wireless communication device 20h is started, and when reaching the switching position 26g, the vehicle enters the G station. The frequency is changed to the frequency notified to be used when the communication is performed, and communication with the wireless communication device 20g is started.

  14 and 15 show an example in which one wireless communication device 20 is installed between stations, similarly, two or more wireless communication devices 20 may be installed. Further, the intermediate point means a midway between the stations, and does not mean a point exactly in the middle of the distance.

(B) Modification of the first embodiment In the first embodiment installed so that the communicable ranges 22 of the radio communication devices 20 at adjacent stations do not overlap, the same communication channel is used at the adjacent stations. However, it is needless to say that different communication channels may be used as in the second embodiment.

(C) Wireless communication In addition, the wireless communication between the ground system 1 and the on-board device 70 is not limited to the wireless communication using a frequency band that can be used by the public, but is similarly applied to the wireless communication using a dedicated frequency band. Applicable.

DESCRIPTION OF SYMBOLS 1 Ground system 10 Central apparatus 102 Operation part, 104 Display part, 106 Sound output part, 108 Communication part 200A, 200B Processing part 202 Standing line management part, 204 Radio wave environment management part 206 1st allocation frequency determination part, 208 1st on-vehicle Change control unit 210 first ground change control unit,
212 Second assigned frequency determination unit, 214 Second on-vehicle change control unit 216 Second ground change control unit 300A, 300B Storage unit 302 First central control program, 304 Wireless communication device information 306 Standing line information, 308 Available frequency information 310 Radio wave environment information, 312 Frequency allocation information 314 Second central control program, 316 Second wireless communication device information 20 Wireless communication device, 22 Communicable range 30 Measurement device 40 Station control device 502 Operation unit, 504 Display unit, 506 Sound output unit , 508 Communication unit 600 Processing unit 602 Radio wave environment notification control unit, 604 Use frequency setting unit 606 Radio communication control unit 700 Storage unit 702 Station control program, 704 Frequency use information 60 Train, 70 On-board device

Claims (3)

A ground system that communicates wirelessly with on-train equipment of a train,
A wireless communication device installed so as to include the station premises in a communicable range corresponding to each station premises,
A measuring device that is installed in each station premises, and measures the electric field strength for each communication channel within a predetermined frequency band in the station premises, as needed ;
A ground control device that determines a communication channel used by the wireless communication device and controls communication with the on-vehicle device via the wireless communication device;
Comprising
The ground control device is:
Based on the measurement results of the measurement devices at the first station and the second station during the stop at the first station when the train stopped at the first station travels to the second station which is the next station. Determining means for determining a communication channel used by the wireless communication devices of the first station and the second station;
The train notifies the on-board device of the determined communication channel so that the train has a communication channel for performing wireless communication with the wireless communication device at the first station and the wireless communication device at the second station. On- vehicle change control means to be set while stopping ,
Means for setting the communication channel used by the wireless communication device of the first station and the second station to the determined communication channel while the train is stopped at the first station ;
Comprising
Ground system. The determination means preferentially determines a communication channel having a smaller electric field strength as a communication channel to be used as a result of measurement by the measurement device at the time of determination.
The ground system according to claim 1. The wireless communication devices of the first station and the second station are installed so that the communicable ranges do not overlap,
The determining means determines that the wireless communication devices at the first station and the second station use the same communication channel.
The ground system according to claim 1 or 2.

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