JP2011090500A - Radio communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain radio communication with an energy saving effect, and to obtain sure communication by preventing the establishment of communication with an unintended radio terminal in entry processing. <P>SOLUTION: In this radio communication system having a plurality of radio terminals 2 and a host 1 which obtains information from the plurality of radio terminals by radio communication, in each of the radio terminals 2, a sensing period detecting means 20 periodically starts a sensor at a sensing period, a sensing information storing means 22 stores measurement information of the sensor by amounts of a plurality of times, and a sensor information transmitting means 24 transmits the measurement information stored in the sensing information storing means to a host 1. The communication period detecting means periodically starts the sensor information transmission means 24 according to the communication period which is a length that is twice the sensing period or longer, and then the sensor information transmission means 24 transmits the measurement information by amounts of a plurality of times that is stored in the sensing information storing means to the host 1 in a batch. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a wireless communication system having a plurality of wireless terminals and a host that obtains information from the plurality of wireless terminals by wireless communication. Further, the present invention relates to a wireless communication system that performs communication between a wireless communication device installed in a railway vehicle and a wireless communication device installed along a traveling line of the vehicle.

  In order to maintain running safety and passenger comfort, railcars communicate various information between devices inside and outside the vehicle. Among them, there are applications where wired connection is difficult and wireless communication is required. As an example, state monitoring of movable parts such as doors, pantographs, carts, and couplers can be cited. When a sensor attached to a monitoring target and a device that receives data from this sensor are connected by wire, the monitoring target is subject to rotation and reciprocation, so the power supply line to the sensor and the communication signal line are subject to fatigue deterioration. Occurs. Therefore, as a communication method between the sensor and a device that receives data from the sensor, a wireless communication method with low power consumption on the premise of battery driving is required.

There is also an application in which information is exchanged between a moving vehicle and ground equipment related to a route on which the vehicle is traveling. In this case, communication is temporarily performed while the vehicle is running or stopped. Unlike regular communication in the vehicle, entry and departure processing is required in which authentication and setting necessary for communication are performed when the communication environment is established, and clearing (stopping connection) is performed again at the end of communication. A communication system that performs primary wireless communication at all times with such an unspecified number of people is called ad hoc wireless communication.

  When considering the power saving of a wireless terminal in ad hoc wireless communication, it is necessary to pay attention not only to reducing power consumption during wireless transmission but also to reducing power consumption during reception standby. This is because the power consumption during reception standby is equivalent to the power consumption during transmission. However, if the reception standby process is simply stopped in order to reduce power consumption, the radio wave transmitted at that time cannot be received, and there is a risk that the reliability of communication is impaired.

  As a method for coping with this, a technique for reducing power consumption by matching transmission / reception times of adjacent terminals, performing synchronous communication, and disconnecting communication power other than the communication time is disclosed (for example, Patent Document 1). ).

JP 2009-042928 A

  In the conventional communication method, a temporal transmission / reception schedule is negotiated between adjacent terminals, and its own reception standby state is controlled according to common time information. Such a method is effective when the direction of information transmission is not fixed and each terminal has the same power source resource. However, in order to provide common time information, it is necessary to provide a clock and a communication protocol for maintaining synchronization, which is a barrier particularly when it is desired to realize a small and inexpensive terminal such as a sensor terminal.

A wireless communication system according to the present invention is a wireless communication system having a plurality of wireless terminals and a host that obtains information from the plurality of wireless terminals by wireless communication.
The wireless terminal is
A sensor that measures the operating state of the device;
Sensing cycle detection means for managing the timing of measurement by the sensor by periodically starting the sensor at a set sensing cycle;
Sensing information storage means for storing measurement information for a plurality of times obtained by the sensor measuring at the sensing cycle;
Sensor information transmission means for transmitting the measurement information stored in the sensing information storage means to the host;
Communication period detection means for managing the timing of transmission by the sensor information transmission means by periodically activating the sensor information transmission means with a communication period longer than the sensing period,
The sensor information transmission means collectively transmits the measurement information for the plurality of times stored in the sensing information storage means to the host,
The host is
Receiving means for receiving the measurement information transmitted from the sensor information transmitting means;
Have

A wireless communication system according to the present invention is a wireless communication system having a first wireless communication device and a second wireless communication device that performs wireless communication with the first wireless communication device.
The first wireless communication device is:
Entry request means for transmitting entry request information for establishing communication with the second wireless communication device;
By activating the entry request means for each cycle, the entry request period detection means for managing the transmission timing of the entry request information;
Based on the signal from the entry request cycle detection means, the power state of the first wireless communication device is switched from the power save mode to the active mode every cycle, and after the predetermined process ends or after a predetermined time elapses, Power management means for switching to the power save mode;
First receiving means for receiving information from the second wireless communication device;
The second wireless communication device is:
Second receiving means for receiving information transmitted from the first wireless communication device;
When the second receiving means receives the entry request information, the entry receiving means transmits entry response information to the first wireless communication device, and
The entry request cycle detection unit extends the cycle when the first receiving unit does not receive the entry response information.

Furthermore, a wireless communication system according to the present invention is a first wireless communication device installed along a traveling line of a railway vehicle, and a first wireless communication device installed in the vehicle and performing wireless communication with the first wireless communication device. In a wireless communication system having two wireless communication devices,
The first wireless communication device is:
Vehicle detection means for detecting the vehicle;
Entry request means for transmitting entry request information for establishing communication with the second wireless communication device when the vehicle detection means detects the vehicle;
First receiving means for receiving information transmitted from the second wireless communication device;
The second wireless communication device is:
Second receiving means for receiving information transmitted from the first wireless communication device;
Information acquisition means for acquiring information relating to the driving situation of the vehicle;
An entry response for sending entry response information to the first wireless communication device based on the entry request information received by the second receiving means and information on the driving situation of the vehicle obtained by the information obtaining means. Means.

Furthermore, a wireless communication system according to the present invention is a first wireless communication device installed in a railway vehicle and a first wireless communication device that is installed along a traveling line of the vehicle and performs wireless communication with the first wireless communication device. In a wireless communication system having two wireless communication devices,
The first wireless communication device is:
Information acquisition means for acquiring information relating to the driving situation of the vehicle;
Based on information on the driving situation of the vehicle acquired by the information acquisition means, entry request means for transmitting entry request information for establishing communication with the second wireless terminal;
First receiving means for receiving information transmitted from the second wireless communication device;
The second wireless communication device is:
Second receiving means for receiving information transmitted from the first wireless communication device;
Vehicle detection means for detecting the vehicle;
And entry response means for sending entry response information to the first wireless communication device based on the entry request information received by the second receiving means and the detection result by the vehicle detecting means.

According to the present invention, wireless communication with high power saving effect can be realized. Further, according to another invention, in entry processing, it is possible to prevent unintended communication establishment with a wireless terminal and to realize reliable communication.

1 is a diagram illustrating a configuration of a wireless communication system in a first embodiment. It is a figure which shows the format of an entry request packet. It is a figure which shows the format of an entry response packet. It is a figure which shows the format of a sensor information transmission packet. It is a figure which shows the table which manages an event. It is a figure which shows the format of a host instruction | indication packet. It is a sequence diagram which shows an example of the time management procedure by a host. It is a sequence diagram which shows the other example of the time management procedure by a host. 6 is a diagram illustrating a configuration of a wireless communication system in a second embodiment. FIG. 10 is a diagram illustrating a configuration of a wireless communication system in a third embodiment. FIG. FIG. 10 is a diagram illustrating a configuration of a wireless communication system in a fourth embodiment.

Embodiments of a wireless communication system according to the present invention will be described below in detail with reference to the drawings. In the following, a vehicle wireless communication system in which a wireless terminal is installed on a railway vehicle or along a traveling line of the vehicle and communicates with a host will be described as an example. Note that the present invention is not limited to the embodiments.

Embodiment 1.
FIG. 1 is a view showing an example of a radio communication system according to the present invention. This wireless communication system is used, for example, as a monitoring device that measures the state of an in-vehicle device using a sensor installed in the in-vehicle device of a railway vehicle, and collects and accumulates the obtained device state information.

1 is a host, 2 is a wireless terminal that performs wireless communication with the host 1, 3 is a vehicle network that controls in-vehicle devices provided in the vehicle, and notifies the host 1 of external information such as the operation status of the vehicle It is. The host 1, the wireless terminal 2, and the vehicle network 3 are all installed in the vehicle.

The wireless terminal 2 acquires the status information of the in-vehicle device controlled by the information of the vehicle network 3 and transmits it to the host 1 by wireless communication. The host 1 collects and stores state information transmitted from the wireless terminal 2. The state information of the in-vehicle device is measured by, for example, a sensor provided in the wireless terminal 2, and is acquired by the wireless terminal 2 as sensor information.

The host 1 has external information receiving means 10 for receiving information on the vehicle network 3, monitoring information storage means 11 for storing sensor information and alert notification from the wireless terminal 2 together with external information, and wireless for registering setting parameters of the wireless terminal 2. Terminal setting management means 12 is provided. In addition, a host instruction unit 13 that issues an instruction to the wireless terminal 2 in response to an instruction from the wireless terminal setting management unit 12, a wireless terminal time management unit 14 that manages a reception time from the wireless terminal 2, It has entry response means 15 for managing withdrawal. Furthermore, it has wireless terminal information management means 16 for managing information of the wireless terminal 2 in communication.

The wireless terminal 2 includes a sensing period detection unit 20 that manages time for performing periodic measurement by a sensor that will be described later, a sensor 21 that acquires state information of the in-vehicle device, and a sensing information storage unit that stores a measurement value of the sensor 21 22. In addition, when it is determined that the communication cycle detection means 23 for managing time for carrying out periodic communication, the sensor information transmission means 24 for collectively transmitting sensor information, and the measured value of the sensor 21 are abnormal values An alert notification unit 25 that performs alert notification is provided.

Furthermore, after entering the request, sending the sensor information and notifying the alert, it is set in the wireless terminal 2 in accordance with the host message receiving means 26 for receiving a message from the host 1 and the host instruction received from the host 1. Host instruction execution means 27 for changing each parameter. In addition, the power management means 28 for switching the power state of the wireless terminal 2 according to each periodic operation, time for performing the entry operation periodically when starting up or when a message from the host cannot be detected in a certain period It has an entry request cycle detection means 29 for managing and an entry request means 210 for executing an entry request.

  In addition, this radio | wireless terminal 2 is installed in the vehicle equipment provided distributed in the vehicle, or its vicinity, and has described as 2a-2c in the figure.

The operation for starting the operation of the system and the operation during steady operation will be described with reference to this figure.
First, as an initial state, the host 1 is in a state where communication with any wireless terminal 2 is not established. At this time, the host 1 accepts only an entry request from the wireless terminal 2 and ignores other communications.

The wireless terminal 2 performs the entry process in an initial state or when no response is detected from the host 1. The entry request period detection means 29 outputs an activation signal at the time of activation or when a response from the host is not detected for a certain period. At this time, the sensing cycle detection unit 20 and the communication cycle detection unit 23 stop the cycle detection and do not perform the state monitoring operation of the in-vehicle device. For this reason, the power management means 28 activates the wireless terminal 2 only by the activation signal of the entry request cycle detection means 29 (transition from the power save mode to the active mode), and after the communication with the host 1 is completed, the power management mode 28 changes from the active mode to the power save mode. Transition to. The activation signal from the entry request cycle detection unit 29 is transmitted to the entry request unit 210 and wirelessly transmits the entry request packet 200.

An example of the format of the entry request packet 200 is shown in FIG. The preamble 201 and the Sync 202 are header information for demodulating a radio signal and extracting information. The DID 203 indicates destination ID information, and since ID information of the host 1 is unknown at the time of entry, an ID indicating broadcast is stored. Here, it is 00.

The SID 204 indicates its own ID information, and is a terminal ID assigned by the host 1. Since this is also unknown at the time of entry, the default ID is FF (hexadecimal notation) here. TYPE 205 stores a code meaning entry. DATA 206 contains terminal specific information for the host 1 to know the type of the wireless terminal 2. For example, the terminal product number, sensor type, basic communication cycle, basic sensing cycle, basic alert notification threshold, calculation type, and the like.

After transmitting the entry request packet 200, the wireless terminal 2 maintains a reception standby state for a certain time. The fixed time is a time required for the host 1 to return the entry response packet 300. Usually, it is a very short time compared to the entry request cycle. When there is no response during this time or when the predetermined processing is terminated, the entry request cycle detection unit 29 shifts the processing to the next cycle detection, and the power management unit 28 changes the wireless terminal 2 from the active mode to the power save mode. Transition.

The entry request cycle does not always have to be constant. Possible causes of no response to the entry request packet 200 include a case where communication is temporarily disabled due to noise or the like, and a case where the host 1 is in a stopped state. In the former case, the wireless terminal 2 should be activated early by repeating activation in a short cycle, and in the latter case, power consumption should be suppressed by repeating it in a long cycle. Therefore, the initial value of the entry request cycle is set to a short time, and the method of extending the cycle with each repetition makes it possible to recover early when communication is temporarily unavailable and prevent waste of power when the host 1 is stopped (when it is absent). Can be compatible.

When the host 1 receives the entry request packet 200, the entry response means 15 assigns a terminal ID to the wireless terminal 2 that has made the entry request, and registers it with the terminal specific information in the wireless terminal information management means 16. In addition, the entry response means 15 transmits an entry response packet 300 via the host instruction means 13.

A format example of the entry response packet 300 is shown in FIG. The same information as the SID 204 stored in the entry request packet 200 is stored as the DID 303. As described above, since the FF (hexadecimal notation) that is the default ID is stored as the SID 204 in the entry request packet 200, the FF (hexadecimal notation) that is the default ID is also stored in the DID 303.

ID information of the host 1 is stored in the SID 304, and code information indicating an entry response is stored in the TYPE 305. The DATA 306 stores a terminal ID assigned to the wireless terminal 2 to which the entry response unit 15 has requested entry.

  When the wireless terminal 2 receives the entry response packet 300 from the host 1, the host message receiving unit 26 notifies the host instruction execution unit 27 of a host instruction (entry instruction for the wireless terminal 2). The host instruction execution unit 27 transmits the terminal ID and host ID stored in the entry response packet 300 to the sensor information transmission unit 24 and the alert notification unit 25, and validates the sensing cycle detection unit 20 and the communication cycle detection unit 23. .

  The sensing cycle detection unit 20 periodically activates the sensor 21 and performs periodic sensor measurement and measurement value recording using the sensor 21 and the sensing information storage unit 22. The alert notification means 25 performs a primary determination as to whether or not the measured value of the sensor 21 is an abnormal value, and performs an alert notification when it is determined as an abnormal value. As this primary determination, it is possible to determine whether or not the measured value exceeds a threshold value, or determination using an arithmetic expression. Further, the communication cycle detection unit 23 periodically activates the sensor information transmission unit 24 and transmits the sensor information stored in the sensing information storage unit 22 to the host 1. Transmission to the host 1 uses a sensor information transmission packet 400.

  FIG. 4 shows a format example of the sensor information transmission packet 400. The host ID is stored as the DID 403, and the terminal ID of the wireless terminal 2 that is the transmission source is stored as the DIS 404. Code information indicating sensor information is stored in TYPE 405, and sensor information (collected sensor information) collected by the wireless terminal 2 and transmitted to the host 1 is stored in DATA 406.

  Usually, the communication cycle is at least twice as long as the sensing cycle, and more preferably at least several times that of the sensing cycle. For example, in the monitoring of a state where the change is relatively slow, such as temperature measurement, the measurement may be performed in units of seconds and monitored in communication cycles of units of several tens of seconds. Generally, the sensing and communication time is a processing time of several milliseconds to several tens of milliseconds, so the activation time for the power save mode is 1/1000, and the state is monitored with very small power consumption. can do. In monitoring, such as vibration, that needs to be measured by high-speed sampling, the sensing cycle is set to the millisecond unit, this is recorded in the sensing information recording unit 22, the communication cycle is set to several tens of seconds, and the sensor information transmission unit 24 vibrates. Process information. For example, high-speed measurement can be realized while suppressing wireless transmission with high power consumption by performing a calculation of sending vibration maximum values for one second for the past 10 times. Further, by narrowing down the measurement points and instructing the host to change the parameter settings to stop sensing when monitoring is unnecessary, lower power consumption can be achieved.

As described above, the sensing information storage unit 22 stores a plurality of measurement values measured by the sensor 21. The sensing information storage means 22 may use a non-volatile storage device in addition to a volatile storage device that temporarily stores measurement values up to the next communication cycle when long-term storage is required.
In addition, the sensing information transmission unit 24 collectively transmits a plurality of measurement values stored in the sensing information storage unit 22 to the host 1. The sensor information transmission unit 24 may process the measured values by a specific calculation method and transmit the measured values for a plurality of times to the host 1.

The host 1 stores the sensor information transmitted from the sensing information transmission unit 24 in the monitoring information storage unit 11.
On the other hand, the host 1 validates the terminal parameter setting change function in the wireless terminal setting management means 12 when the wireless terminal 2 that requested entry is registered in the wireless terminal information management means 16. The wireless terminal setting management unit 12 includes a table 500 for managing events as shown in FIG.

The table 500 includes information including external information 501, a range 502, a terminal type 503, a parameter type 504, and a value 505. This is a table showing the operation content of the sensor 21 (or the wireless terminal 2) when the same conditions as the external information are satisfied. For example, when the vehicle speed is 40-50 km / h, the wireless terminal 2 having the temperature sensor A indicates that measurement is performed at a sensing period of 30 seconds.

Information in the table 500 is registered in the host 1 in advance. In addition, about the registration method to the host 1, you may register from a cab console etc. via the vehicle network 3 other than connecting a dedicated terminal to the host 1 and registering. In addition, if a communication means with the ground is provided, it can be registered remotely from a management room such as a base or a commander.
As described above, the wireless terminal setting management unit 12 registers the parameter for setting the operation content of the wireless terminal 2, and instructs the change of the parameter in the following procedure.

The wireless terminal setting management unit 12 collates the state of the external information received from the vehicle network 3 by the external information receiving unit 10 with the table 500 shown in FIG. The external information includes, for example, information (speed, travel distance, time, etc.) indicating the driving situation of the vehicle. If the state of the external information matches the table 500, the terminal ID of the wireless terminal 2 whose parameter is to be changed and the specific change setting contents are stored in the host based on the terminal information registered in the wireless terminal information management means 16. This is transmitted to the instruction means 13. For example, if the state of the vehicle speed is 45 km / h, the host instruction means indicates that the terminal ID of the wireless terminal 2 having the temperature sensor A and the sensing cycle are changed to 30 seconds because the conditions of the table 500 are met. 13 is transmitted.

When the host instruction means 13 receives sensor information transmission from the wireless terminal 2 subject to parameter change, the host instruction means 13 transmits a host instruction storing the parameter change content to the wireless terminal 2 as a response. In the above example, information indicating that the sensing cycle is changed to 30 seconds is stored in the host instruction for the wireless terminal 2 having the sensor A. A host instruction packet 600 is used for a host instruction to the wireless terminal 2.

FIG. 6 shows a format example of the host instruction packet 600. The DID 603 stores the terminal ID of the destination terminal, and the SID 604 stores the host ID. TYPE 605 stores code information indicating that the type of data to be transmitted is a parameter, and DATA 606 stores a parameter change value.

  The contents of the table 500 and the contents of parameters for setting the operation contents of the wireless terminal 2 include, for example, sensor operation contents (measurement items, measurement contents, measurement validity / invalidity, stop of sensing, etc.), sensing period, communication period The contents of the information transmitted by the sensor information transmission means 24 to the host 1 (number of measurement values to be transmitted, calculation method of the measurement values), whether or not the sensor information can be stored in the sensing information storage means 22, and the alert notification means 25 is primary. This includes threshold values and arithmetic expressions used for determination, switching of a volatile storage device and a nonvolatile storage device used when sensor information is stored by the sensing information storage means 22, and the like.

When the host instruction execution means 27 of the wireless terminal 2 receives the host instruction packet 600 in which the parameter change contents are stored, the host instruction execution means 27 notifies the change contents to the means requiring the parameter change, and changes the operation of the means.
The wireless terminal 2 is in a reception state for a certain period of time after transmitting sensor information and notifying an alert. If no message is transmitted from the host 1 during this period, the power management means 28 changes the power state of the wireless terminal 2 from the active mode to Switch to save mode.

Further, the wireless terminal time management means 14 monitors the reception time intervals of the plurality of wireless terminals 2. FIG. 7 shows a time management operation. FIG. 7 shows a case where the host 1 is communicating with the three wireless terminals 2a to 2c at the same period P. In this case, the wireless terminal time management means 14 divides the period P into three with reference to the period of the wireless terminal 2a, and the expected reception time of the wireless terminal 2b after the time P / 3 from the reception of the sensor information from the wireless terminal 2a. Then, the time 2P / 3 after the reception of the sensor information from the wireless terminal 2a is set as the expected reception time of the wireless terminal 2c. Then, the wireless terminal time management means 14 compares the expected reception time with the actual reception time.

When the wireless terminal 2b receives x earlier than the expected time, the wireless terminal time management means 14 sends the correction time of P + x to the wireless terminal 2b via the host instruction means 13 as a phase correction instruction. Send to. Similarly, when the wireless terminal 2c receives a signal delayed by y from the expected time, the wireless terminal time management unit 14 sets the Py correction time as a phase correction instruction to the wireless terminal 2c. To the wireless terminal 2c.

Each wireless terminal measures the designated time by the communication period detection means 23 for one period according to the instruction, and restores it from the next period. For example, the wireless terminal 2b transmits sensor information to the host 1 when measuring time P + x, and the wireless terminal 2c transmits sensor information when measuring time P-y. Thereafter, the cycle of the wireless terminals 2b and 2c is returned to the original cycle P.
As described above, the communication cycle detection unit 23 adjusts the timing for transmitting the sensor information based on the correction time.

By doing in this way, the time interval of sensor information transmission of wireless terminal 2a, 2b, 2c can be equalized, interference between a plurality of wireless terminals can be prevented, and stable communication can be realized.

As a method of time management, in addition to equalization as in this example, a communication slot for a certain period of time may be decided by the host, and phase correction may be performed so that the communication time of each terminal is within the assigned slot. good.
FIG. 8 shows an operation of assigning slots and managing time. The host assigns slots a, b, and c to the wireless terminals 2a, 2b, and 2c, respectively. Since the wireless terminal 2b has received the signal delayed by x from the slot b, the wireless terminal 2b transmits the correction time of Px to the wireless terminal 2b via the host instruction means 13. Further, since the wireless terminal 2c has received y earlier than the slot c, the wireless terminal 2c transmits a correction time of P + y to the wireless terminal 2c. The wireless terminals 2b and 2c perform phase correction at the instructed time, and are received in the assigned slot from the next time.

  The wireless terminal information management means 16 registers the terminal specific information and the assigned terminal ID when there is a request for entry from a new wireless terminal, but the host 1 does not receive sensor information from the wireless terminal for a certain period. The registered information is deleted.

With the above processing, the wireless terminal can repeat short-term processing execution and long-term power save mode according to periodic processing, thus reducing power consumption and enabling battery-operated wireless terminals to operate for a long time. It can be.

In addition, when the host 1 is inactive, each wireless terminal recognizes the host inactivity and repeats the entry communication while extending the period. Therefore, in the case of a primary communication interruption, the wireless terminal recovers early and makes a long-term Communication power can be reduced when the host is absent, and power consumption when the system is inactive can be suppressed.

  Furthermore, since the host 1 monitors the reception arrival time interval of each wireless terminal and instructs the wireless terminal to perform phase correction, the communication interval is maintained without time synchronization, preventing information transmission failure due to communication collision, and high quality Communication can be realized.

  In addition, since the wireless terminal determination management unit 12 changes the setting parameters of the wireless terminal 2, the host 1 can collect necessary sensor information according to the situation. Particularly in a railway vehicle in which the vehicle situation changes from moment to moment, it is particularly effective to change parameters according to the driving situation of the vehicle.

Embodiment 2.
In the first embodiment, the wireless communication system installed in the vehicle and having a fixed relationship between the terminal and the host has been described. Here, the terminal installed on the ground facility along the traveling line of the vehicle and the host on the vehicle are A wireless communication system that establishes communication temporarily and transmits information will be described.

FIG. 9 shows a configuration diagram of the present embodiment. The function for the same name is the same as in FIG. However, the configurations of FIG. 9 and FIG. 1 are different in the following points. That is, in the host 1, the entry response unit 15 refers to information obtained by the external information receiving unit 10 from the vehicle network 3. Further, the wireless terminal 2 includes train passage detection means 211 that detects whether or not the train has passed by a sensor that detects external vehicle state information and vehicles, and the detection result of the train passage detection means 211 is used as an entry request cycle detection means. 29 references. The train passage detection unit 211 is an example of a vehicle detection unit.

  As a case where the wireless terminal 2 is installed in the ground facility, it is assumed that the wireless terminal 2 is installed in, for example, a measuring device that detects the rising of the wheel, a device that measures the state of the wheel and the pantograph from the ground side, or the like. The wireless terminal 2 monitors the climbing of the wheels, the state of the wheels and the pantograph, and transmits the monitoring information to the host 1 of the vehicle under measurement.

However, if a similar wireless terminal exists in the vicinity, the host 1 can communicate with either wireless terminal, so that communication is established with another wireless terminal and there is a risk of misrecognizing other monitoring information. Therefore, a means for detecting passage of a train is provided, and a wireless terminal and a host to be expected can communicate with each other by collating the traveling state of the vehicle and the state of passage of the train on the ground.

The operation of establishing communication according to this embodiment will be specifically described.
In the initial state, the wireless terminal 2 is in a normal state in which neither communication nor entry request is made. When the train passes, the vehicle passage detection unit 211 of the wireless terminal 2 detects the passage and validates the entry request cycle detection unit 29. The entry request cycle detection means 29 issues an activation signal at regular intervals, and the entry request means 210 that receives this signal sends an entry request.
The format of the entry request packet transmitted at this time is the same as the format shown in FIG. However, as the terminal specific information of DATA 206, position information indicating the location where the wireless terminal 2 is installed and information regarding the traveling direction of the line on which the wireless terminal 2 is installed are stored.

The entry request of the wireless terminal 2 is received by the host 1 installed in the traveling vehicle. Here, the entry response means 15 of the host 1 obtains information specifying a travel location such as a kilometer or the like that can be acquired from the vehicle network 3 via the external information receiving means 10 and information on the traveling direction, and is included in the entry request. It collates with the positional information on the terminal 2 and information on the traveling direction.

When the travel location and the installation position information of the terminal are equal, the entry response means 15 determines that it is an entry request from the wireless terminal 2 installed on the track passing through and performs an entry response process. The format of the entry response packet 300 is the same as that in FIG. On the other hand, when the location information is far away or the traveling direction is different, it is determined that the wireless terminal is not a wireless terminal to be entered, and the entry response is not performed.

  The wireless terminal 2 receives an entry response from the host 1 by the host message receiving unit 26, and the host instruction execution unit 27 receives the host ID and the terminal ID assigned to the wireless terminal 2 by the host 1 and the sensor information transmission unit 24. It passes to the alert notification means 25.

  By such a procedure, communication between the wireless terminal 2 installed on the ground and the host 1 is established. Thereafter, the sensor information transmission unit 24 and the alert notification unit 25 transmit information to the host 1. This information transmission includes the transmission of sensor information and alert notification described in the first embodiment, and is executed in the same procedure as in the first embodiment.

  As described above, in order to collate and establish the communication establishment between the wireless terminal 2 installed on the ground and the host 1 with the location information included in each, for example, similar wireless terminals are installed on the forward path and the return path, When the train passes at the same time, it is possible to exchange information without interference between the communication on the outbound route and the communication on the return route.

Embodiment 3
In the second embodiment, communication establishment between the wireless terminal 2 installed in the ground facility and the host 1 on the vehicle has been described. As another example of inter-vehicle communication, the vehicle is connected to the PC installed in the vehicle base. A wireless communication system for automatically transmitting the monitoring information collected in step 1 will be described.

FIG. 10 shows the configuration of this embodiment. In the present embodiment, the host 1 on the vehicle described in the first embodiment and the second embodiment transmits information to the ground host 5 via the wireless terminal 4 for transmission to the base. Therefore, the wireless terminal 4 is installed in the vehicle and the host 5 is installed on the ground.

Note that the difference between the host 1 of the first and second embodiments and the host 5 of the present embodiment is that the host 5 detects the train stop position by detecting that the vehicle is stopped at the train stop position by a sensor or the like. The means 51 is provided. Those having the same name as the means in the host 1 have the same function. The host 5 is installed for each track in the base, and the train stop position detecting means 51 detects whether the vehicle is stopped on the track where the host 5 is installed. This train stop position detection means 51 is an example of a vehicle detection means.

The difference between the wireless terminal 2 according to the first and second embodiments and the wireless terminal 4 according to the present embodiment is that the wireless terminal 4 stores information on the train stop state included in the vehicle information 40 from the vehicle network 3 or the host 1. The train stop state detecting means 41 for acquiring and detecting the stop and the monitoring information transmitting means 42 for transmitting the monitoring information from the monitoring host 47 instead of the sensor information are provided. Components having the same names as the means in the wireless terminal 2 have the same functions. The monitoring host 47 includes the host 1 on the vehicle described in the first and second embodiments. In this case, the monitoring information transmission unit 42 of the host 4 acquires information stored in the monitoring information storage unit 11 of the host 1. To do.

A specific communication establishment operation will be described.
In the initial state, the wireless terminal 4 is in a normal state in which neither communication nor entry request is made. When the train enters the base and stops, the vehicle stop state detection means 41 detects the stop of the vehicle based on the vehicle information 40 obtained from the vehicle network 3, the host 1, etc., and makes the entry request cycle detection means 43 effective. The entry request cycle detection means 43 issues an activation signal at regular time intervals, and the entry request means 44 that receives this signal sends an entry request. The format of the entry request packet transmitted at this time is the same as the format shown in FIG.

The entry request of the wireless terminal 4 is received by the host 5 installed in the base. Here, the entry response means 52 of the host 5 confirms the detection state of the vehicle stop position detection means 51. When the vehicle stop position detecting means 51 detects the stop of the vehicle, the entry response means 52 determines that it is an entry request from the wireless terminal 4 installed in the vehicle that has entered the line, and enters. Perform response processing. The format of the entry response packet 300 is the same as that in FIG. Conversely, the host 5 of the base corresponding to another track does not make an entry response because the vehicle stop position detection means 51 is in an undetected state.

The wireless terminal 4 receives the entry response packet 300 from the host 5 by the host message receiving unit 45, passes the host ID assigned by the host instruction execution unit 46 to the monitoring information transmission unit 42, and sends it to the host 5. To communicate information.

  Communication between the wireless terminal 4 and the host 5 is established by such a procedure. Thereafter, the monitoring information transmission means 42 transmits the monitoring information to the host 5, and the host 5 transmits the received information to the PC 54.

  As described above, in order to collate and establish the communication establishment between the host 5 installed on the ground and the wireless terminal 4 on the vehicle with the existence of the train and stop detection information provided for each, Even when the train repeats incoming lines frequently, communication corresponding to each line can be exchanged without interference.

Embodiment 4 FIG.
Communication between a platform door and a vehicle will be described as another example for transmitting information between ground vehicles when the train is stopped as shown in the third embodiment. By exchanging information between the host and the wireless terminal, the home door is also opened and closed in conjunction with the door opening and closing operation of the vehicle.

FIG. 11 shows a configuration diagram of the present embodiment. As a configuration different from the hosts 1 and 5 so far, the host 5 according to the present embodiment includes a host unique information storage unit 54 that stores host unique information and a reception strength detection unit 55 that measures the strength of a wireless reception signal. Is provided. The host specific information storage means 54 stores information for specifying whether the home door on which the host is installed is on the mountain side or the sea side of the home. The means having the same name have the same functions as the hosts 1 and 5 in the other embodiments.

  Further, as a configuration different from the wireless terminals 2 and 4 so far, the operation button 48 of the home door is connected to the wireless terminal 4 of the present embodiment, and operation information transmission means 49 for wirelessly transmitting information of the operation button 48, State change notification means 410 for wirelessly transmitting the change of the operation button is provided. In addition, about the means with the same name, it has the same function as the radio | wireless terminals 2 and 4 in other embodiment. In this embodiment, both the vehicle door and the home door can be opened and closed by operating the operation button 48.

  For explanation, in this example, it is assumed that there are two lines traveling in the same direction in two homes. One of the two platforms allows one to get on and off from the train on the tracks on both sides, and the installed home doors are called D1-sea side and D1-mountain side. The home door installed in the other platform is D2-sea. For train A, platform door D1-sea side opens and closes, and for train B, platform door D1-mountain side or D2-sea side opens and closes. Further, the train door is opened and closed by the driver, and is operated by a total of four buttons (operation buttons 48): open / close on the mountain side and open / close on the sea side.

The host 5 according to the present embodiment is provided on each of the above-described home doors D1-sea side, D1-mountain side, D2-sea side, and the door control means 56 controls each door. In the following, the hosts 5 provided for each are referred to as 5a, 5b, and 5c, but all have the same configuration.
Moreover, the radio | wireless terminal 4 of this Embodiment is provided in each of the trains A and B. Hereinafter, the wireless terminals 4a and 4b are provided respectively, but both have the same configuration.

  First, processing when the train A enters the line will be described. When the train A enters the line and stops at the platform, the wireless terminal 4a on the train A detects the stop of the vehicle from the vehicle information by the vehicle stop state detection unit 41 and validates the entry request cycle detection unit 43. The entry request cycle detection means 43 issues an activation signal at regular time intervals, and the entry request means 44 that receives this signal sends an entry request. The format of the entry request packet 200 at this time is the same as the format of the entry request packet shown in FIG.

The entry request of the wireless terminal 4a is received by the hosts 5a to 5c installed in each home door. In this state, it is not known which line the train has entered, but it is only the host 5a that the train stop position detection means 51 indicates the detection state. Therefore, the entry response means 52 of the host 5a instructs the host instruction means 53 to execute the entry response. The host instruction unit 53 transmits an entry response packet 300 shown in FIG. 3 to the wireless terminal 4a. Here, the host ID includes an identification value (information indicating the home mountain side or the sea side) indicating the installation direction of the host obtained from the host unique information storage unit 54. In other words, this identification value is unique information for specifying the host 5a.

The host message receiving means 45 of the wireless terminal 4a receives the entry response from the host 5a, and the host instruction execution means 46 uses the host ID and terminal ID stored in the entry response as the operation information transmission means 49 and the state change notification means. 410.
In addition, the host instruction execution unit 46 enables the communication cycle detection unit 411.

  Communication between the wireless terminal 4a and the host 5a is established by such a procedure. The wireless terminal 4a can identify the host 5a as a transmission destination by the host ID, and performs the following communication.

When the state of the operation button 48 changes, the state change notification means 410 transmits information indicating the state of the operation button to the host 5a. Even if the state of the operation button 48 does not change, the operation information transmission unit 49 transmits information indicating the state of the operation button 48 to the host 5a at a cycle designated by the communication cycle detection unit 411. The information indicating the state of the operation button 48 indicates, for example, the opening or closing of the door D1-the sea side door.
The host 5 a receives this information and transmits the information to the home door control device 56, so that the home door 1-the sea side door can be opened and closed by the door opening / closing operation of the vehicle A.

  Next, a case where the train B enters the line while the train A is stopped will be described. When the train B enters and stops at the platform, the wireless terminal 4b on the train B detects the stop by the vehicle stop state detection means 41 and validates the entry request cycle detection means 43.

  The entry request cycle detection means 43 issues an activation signal at regular time intervals, and the entry request means 44 that receives this signal sends an entry request. The entry request of the wireless terminal 4b is received by the hosts 5b and 5c installed in each home door. Since the host 5a has already established communication with the wireless terminal 4a, the entry request is ignored even if it is received. Furthermore, the train stop position detecting means 51 indicates the detection state of both the hosts 5b and 5c. In this case, the entry response unit 52 of the hosts 5 b and 5 c outputs an entry response instruction to the host instruction unit 53.

  The host instruction means 53 of each of the hosts 5b and 5c obtains an identification value indicating the installation direction of the own station, stored in the host unique information storage means 54. Specifically, an identification value indicating the mountain side is acquired in the host 5b, and an identification value indicating the sea side is acquired in the host 5c. Thereafter, the host instructing means 53 of the hosts 5b and 5c respectively transmit an entry response packet 300 to the wireless terminal 4b. For the host ID in each entry response packet 300, an identification value indicating the mountain side and the sea side acquired from the host unique information storage means 54 is set (this identification value is unique information for identifying the host).

  The host message receiving means 45 of the wireless terminal 4b receives both entry responses from the hosts 5b and 5c, and the host instruction execution means 46 stores the entry information packet 300 in the operation information transmission means 49 and the state change notification means 410, respectively. Passed host ID and terminal ID are passed.

  At this stage, the wireless terminal 4b can communicate with any of the hosts 5b and 5c.

  Further, the host instruction execution unit 46 enables the communication cycle detection unit 23. When the state of the operation button 48 changes, the state change notification means 410 transmits information indicating the state of the operation button. Even if the state of the operation button 48 does not change, the operation information transmission unit 49 transmits information indicating the state of the operation button 48 to the host in the cycle designated by the communication cycle detection unit 411.

  At this time, it is selected which of the hosts 5b and 5c is to be transmitted according to the sea side and mountain side values of the operation button 48. In other words, if the state indicates that the mountain-side open button has been pressed, the host ID identification value transmits information to the host 5b indicating the mountain side, indicating that the mountain-side open button has been pressed. If it is in the state, the identification value of the host ID is transmitted to the host 5c indicating the sea side. In other words, according to the content of the information transmitted by the wireless terminal 4b, one of the hosts 5b and 5c is specified as a transmission destination, and the information is transmitted to the specified host.

In this way, when a train enters with a time difference between a plurality of tracks, the host that has established communication does not return an entry response, so the wireless terminal 4 on the vehicle and the host 5 of an appropriate home door. Can establish communication. Even when there are platform doors on both sides, the information is transmitted to the host 5 in the same direction as the door to be opened and closed of the train, so that the platform door on the other side will not be opened or closed.

  Finally, the case where the trains A and B enter simultaneously will be described. The radio terminals 4a and 4b detect the stop of the train almost simultaneously and send an entry request. The hosts 5a to 5c also detect a train stop at the same time. Each of the hosts 5a to 5c detects an entry request of the wireless terminals 4a and 4b by monitoring a signal from the wireless terminal received during the entry request cycle.

  When the entry response unit 52 receives an entry request from each of the wireless terminals 4a and 4b, the entry response unit 52 acquires a detection result from the reception intensity detection unit 55. The reception intensity detection means 55 detects the reception intensity when receiving an entry request from each of the wireless terminals 4 a and 4 b and outputs the detection result to the entry response means 52. The entry response means 52 of each host compares the reception intensity at the time of entry request reception of the wireless terminals 4a and 4b.

  In general, a radio signal is attenuated according to a distance. Accordingly, since the wireless terminal 4a having a shorter distance exhibits higher reception strength with respect to the host 5a, the host 5a transmits an entry response to the wireless terminal 4a. Similarly, since the wireless terminal 4b shows higher reception strength with respect to the host 5b, the host 5c also transmits an entry response to the wireless terminal 4b. In this way, the entry response unit 52 identifies and transmits a wireless terminal that transmits the entry response information from among a plurality of wireless terminals based on the detection result of the reception intensity detection unit 55.

  Through such a procedure, communication between the wireless terminals 4a to 4c and the hosts 5a to 5c is established. After this, the operation is the same as that described when the train B enters the line while the train A is stopped.

As described above, when a plurality of wireless terminals are detected, the determination is made based on the reception strength, and communication is established only with a communication partner having a short distance. Therefore, communication between the wireless terminal on the vehicle and the appropriate home door host is established. be able to.
Note that the reception intensity varies not only by the distance but also by the influence of an obstacle and the influence of the installation environment. For this reason, a width may be given to the selection determination, and if the difference is within the width, the determination may be impossible and an error may be returned.
The communication establishment is reset when the train stop state detecting means 41 of the wireless terminal 4 indicates non-detection by transmission. On the other hand, the host is reset when reception from the wireless terminal 4 that has given the entry response is no longer detected.

In this embodiment, it has been described that the opening and closing of the home door is operated by the operation button 48 provided in the vehicle. However, the device to be controlled is not limited to the home door, but other devices provided outside the vehicle. The present embodiment can also be applied to the operation of this device. In this case, an operation button 48 corresponding to the device is provided in the vehicle, and a control means for controlling the other equipment is connected to the host 5 instead of the door control means 56.

The present invention has been described based on the embodiments. It is understood by those skilled in the art that these embodiments are exemplifications, and that various modifications can be made to combinations of the respective constituent elements and processing processes, and such modifications are also within the scope of the present invention. By the way.

As described above, the present invention is useful for a wireless communication system that performs communication between a plurality of wireless communication devices, particularly a vehicle wireless communication system that performs wireless communication in a railway vehicle or between a vehicle side and a ground facility side. is there.

1, 5 Host 2, 4 Wireless terminal 3 Vehicle network 10 External information receiving means 11 Monitoring information storage means 12 Wireless terminal setting management means 13, 53 Host instruction means 14 Wireless terminal time management means 15, 52 Entry response means 16 Wireless terminal information Management unit 20 Sensing cycle detection unit 21 Sensor 22 Sensing information storage unit 23, 411 Communication cycle detection unit 24 Sensor information transmission unit 25 Alert notification unit 26, 45 Host message reception unit 27, 46 Host instruction execution unit 28 Power management unit 29, 43 entry request cycle detection means 40 vehicle information 41 train stop state detection means 42 monitoring information transmission means 47 monitoring host 48 operation button 49 operation information transmission means 51 train stop position detection means 54 host specific information storage means 55 reception intensity detection means 56 door Refer to control means 210 and 44 Entrance request means 211 Train passage detection means 410 State change notification means

Claims (14)

In a wireless communication system having a plurality of wireless terminals and a host that obtains information from the plurality of wireless terminals by wireless communication,
The wireless terminal is
A sensor that measures the operating state of the device;
Sensing cycle detection means for managing the timing of measurement by the sensor by periodically starting the sensor with a set sensing cycle;
Sensing information storage means for storing measurement information for a plurality of times obtained by the sensor measuring at the sensing cycle;
Sensor information transmission means for transmitting the measurement information stored in the sensing information storage means to the host;
Communication period detection means for managing the timing of transmission by the sensor information transmission means by periodically activating the sensor information transmission means with a communication period longer than the sensing period,
The sensor information transmission means collectively transmits the measurement information for the plurality of times stored in the sensing information storage means to the host,
The host is
Receiving means for receiving the measurement information transmitted from the sensor information transmitting means;
A wireless communication system comprising: The host is
A time management means for calculating a correction time based on a difference between a reception time of the measurement information from the wireless terminal and a preset expected reception time;
Host instruction means for transmitting correction instruction information including information on the correction time to the wireless terminal;
The wireless communication system according to claim 1, wherein the communication cycle detection unit adjusts a timing of starting the sensor information transmission unit based on the correction time included in the correction instruction information. The host is
Registering parameters for setting the operation content of the wireless terminal, and setting management means for instructing to change the parameters;
Based on an instruction from the setting management means, host instruction means for transmitting instruction information including the parameter change content to the wireless terminal,
The wireless terminal is
The wireless communication system according to claim 1, wherein the operation of the wireless terminal is changed based on a change content of the parameter included in the instruction information. The wireless terminal, based on the change contents of the parameter, the operation contents of the sensor, the sensing period, the communication period, the contents of information transmitted by the sensor information transmission means, or the measurement information to the sensing information storage means 4. The wireless communication system according to claim 3, wherein the stored contents of the wireless communication system are changed. The wireless terminal is
Based on the signals from the sensing cycle detection means and the communication cycle detection means, the power state of the wireless terminal is switched from the power saving mode to the active mode at the sensing cycle and the communication cycle, and after a predetermined process ends or a predetermined time has elapsed. The wireless communication system according to claim 1, further comprising power management means for switching from the active mode to the power save mode later. The plurality of wireless terminals are installed on a railway vehicle or along a traveling line of the vehicle,
The sensor measures an operating state of an in-vehicle device installed in the vehicle or an operating state of the vehicle,
The host is provided in the vehicle,
The wireless communication system according to claim 3, wherein the setting management unit instructs to change the parameter based on information indicating a driving situation of the vehicle obtained from a network in the vehicle. In a wireless communication system having a first wireless communication device and a second wireless communication device that performs wireless communication between the first wireless communication device,
The first wireless communication device is:
Entry request means for transmitting entry request information for establishing communication with the second wireless communication device;
By activating the entry request means for each cycle, the entry request period detection means for managing the transmission timing of the entry request information;
Based on the signal from the entry request cycle detection means, the power state of the first wireless communication device is switched from the power save mode to the active mode every cycle, and after the predetermined process ends or after a predetermined time elapses, Power management means for switching to the power save mode;
First receiving means for receiving information from the second wireless communication device;
The second wireless communication device is:
Second receiving means for receiving information transmitted from the first wireless communication device;
When the second receiving means receives the entry request information, the entry receiving means transmits entry response information to the first wireless communication device, and
The wireless communication system, wherein the entry request cycle detection unit extends the cycle when the first receiving unit does not receive the entry response information. A wireless communication system having a first wireless communication device installed along a traveling line of a railway vehicle and a second wireless communication device installed in the vehicle and performing wireless communication with the first wireless communication device In
The first wireless communication device is:
Vehicle detection means for detecting the vehicle;
Entry request means for transmitting entry request information for establishing communication with the second wireless communication device when the vehicle detection means detects the vehicle;
First receiving means for receiving information transmitted from the second wireless communication device;
The second wireless communication device is:
Second receiving means for receiving information transmitted from the first wireless communication device;
Information acquisition means for acquiring information relating to the driving situation of the vehicle;
An entry response for sending entry response information to the first wireless communication device based on the entry request information received by the second receiving means and information on the driving situation of the vehicle obtained by the information obtaining means. And a wireless communication system. The entry request means transmits entry request information including position information of the first wireless communication device,
The entry response means collates the position information of the first wireless communication device included in the entry request information with information related to the driving situation of the vehicle, and based on the comparison result, the first wireless communication device. The wireless communication system according to claim 8, wherein the participation response information is transmitted. A wireless communication system comprising: a first wireless communication device installed in a railway vehicle; and a second wireless communication device installed along a traveling line of the vehicle and performing wireless communication with the first wireless communication device. In
The first wireless communication device is:
Information acquisition means for acquiring information relating to the driving situation of the vehicle;
Based on information on the driving situation of the vehicle acquired by the information acquisition means, entry request means for transmitting entry request information for establishing communication with the second wireless terminal;
First receiving means for receiving information transmitted from the second wireless communication device;
The second wireless communication device is:
Second receiving means for receiving information transmitted from the first wireless communication device;
Vehicle detection means for detecting the vehicle;
And entry response means for transmitting entry response information to the first wireless communication device based on the entry request information received by the second receiving means and the detection result by the vehicle detecting means. Wireless communication system.   The wireless communication system according to claim 8 or 10, wherein the vehicle detection means detects passage or stop of the vehicle. The entry response means transmits entry response information including unique information identifying the second wireless communication device,
The first wireless communication device is:
And a transmission unit configured to transmit the information acquired by the first wireless communication device to the second wireless communication device based on the unique information included in the entry response information. 10. The wireless communication system according to 10. The second wireless communication device is:
When entry request information is received from a plurality of wireless communication devices, it has reception strength detection means for detecting the strength of the received signal,
11. The wireless communication system according to claim 10, wherein a wireless communication device that transmits the entry response information is specified from the plurality of wireless communication devices based on a detection result of the reception intensity detection unit. Operating means provided in the vehicle for operating equipment provided outside the vehicle;
State change notifying means for transmitting the state change information when the state of the operation means is changed after receiving the entry response information provided in the first wireless communication device;
11. The radio according to claim 10, further comprising a control unit that is connected to the second radio communication device and controls the device based on the state change information received by the second reception unit. Communications system.

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