JP2008105485A - Ground-vehicle information transmission device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ground-vehicle information transmission device capable of detecting the train position with high accuracy on the on-board side without providing any transponder or wayside coil on a traveling path of a train. <P>SOLUTION: Loop antennas 1T-4T are arranged with a spacing therebetween along a train traveling path 5. The adjacent loop antennas, for example, the loop antennas 1T, 2T transmit ATC signals S11, S12 set to the carrier frequencies different from each other. An onboard device 3 decodes the carrier frequency of the ATC signal received from the loop antenna, determines that a self train TR is located on a boundary between the loop antennas when the carrier frequency of the ATC signal is changed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a ground-to-vehicle information transmission apparatus applied in, for example, a monorail or a new transportation system.

  For monorails and new transportation systems, a ground-to-vehicle information transmission system is known that sends and receives necessary information signals between the ground and the vehicle via loop antennas laid along the train route. ing.

  In such a ground-to-vehicle information transmission system, highly accurate pattern control is required such as stopping the train at an accurate position. For that purpose, the position of the train must be detected with high accuracy on the upper side of the vehicle.

  As a method for detecting the position of the train on the upper side of the vehicle, a method is known in which the speed of the train is measured by a speed generator mounted on the train, and the position information of the train is calculated from the speed information from the speed generator. Yes. However, in this method, the actual speed of the train is not reflected in the speed information from the speed generator due to the idling or sliding of the wheel, and there may be an error in the position information of the train. For this reason, it is necessary to correct train position information.

  As a method for correcting the train position information on the upper side of the vehicle, laying correction means such as a transponder or a ground element along the train traveling path, and when the train passes over the correction means, There is known a method of receiving position information from a correction unit and correcting train position information based on the position information from the correction unit (see Patent Document 1).

  However, this method has a problem that a large number of correction means must be laid along the train traveling path, and the laying cost or maintenance cost of the correction means is high.

  Patent Document 2 discloses a technique for correcting train position information on the upper side of the vehicle without providing correction means such as a transponder or a ground unit. That is, a signal is sent from the boundary of the track circuit to the track circuit on the ground side, and a signal from the track circuit is received on the vehicle upper side. When the signal reception intensity changes on the vehicle upper side, it is determined that the train has passed the boundary of the track circuit, and the train position information is updated.

However, in this disclosed technology, when the signal flowing in the track circuit becomes no signal due to a failure of the ground side equipment, the train erroneously determines that the train has passed the track circuit boundary on the upper side of the vehicle, An error may occur in the position information. For this reason, it is difficult to satisfy the principle of fail safe.
JP 2002-87264 A JP 2005-178614 A

  An object of the present invention is to provide a ground-to-vehicle information transmission apparatus capable of detecting a train position with high accuracy on the upper side of a vehicle without providing a transponder, a ground element, or the like on a traveling route of the train.

  In order to solve the above-described problem, a ground-to-vehicle information transmission apparatus according to the present invention includes a plurality of loop antennas and an on-vehicle apparatus.

  The loop antennas are arranged at intervals along the train traveling path, and adjacent loop antennas transmit ATC signals set to different carrier frequencies to the vehicle upper side.

  The on-board device decodes the carrier frequency of the ATC signal received from the loop antenna, and determines that the own train is located on the boundary between the loop antennas when the carrier frequency of the ATC signal is switched.

  Consider a case where a train equipped with an on-board device travels on a train travel path. First, in the state before the train is located on a loop and enters the boundary between the loop antennas, the onboard device receives only the ATC signal from the loop antenna, and is thus decoded by the onboard device. The carrier frequency of the ATC signal is constant.

  Next, when the train enters the boundary between the loop antennas, the on-board device receives an ATC signal from another loop antenna instead of receiving the ATC signal from the loop antenna so far. Therefore, the carrier frequency of the ATC signal received by the on-board device is switched, and at this time, the on-board device determines that the own train is located on the boundary between the loop antennas.

  Since the length of each loop antenna along the train travel path is clearly determined when the loop antenna is laid, the boundary position between the loop antennas can be grasped as kilometer information of the train travel path. Therefore, the accuracy of train position detection can be improved by calculating the position of the own train from the boundary position between the loop antennas based on the determination result that is determined that the own train is located on the boundary between the loop antennas. In order to increase the accuracy of train position detection, it is not necessary to provide a transponder or ground unit on the train travel path.

  Furthermore, since the on-board device determines that the own train is located on the boundary between the loop antennas when the carrier frequency of the ATC signal is switched, the ATC signal is not transmitted from the ground side due to a failure of the loop coil, for example. There is no risk of erroneously determining the train position even when it becomes a signal. Therefore, the fail safe principle can be satisfied.

  As described above, according to the present invention, there is provided a ground-to-vehicle information transmission device capable of detecting the train position with high accuracy on the upper side of the train without providing a transponder or a ground unit on the train travel path. can do.

  Other features of the present invention and the operational effects thereof will be described in more detail by way of examples with reference to the accompanying drawings.

  FIG. 1 is a diagram for explaining an embodiment of a ground-to-vehicle information transmission apparatus according to the present invention. The illustrated on-vehicle / ground-to-ground information transmission device is used for, for example, a monorail, a rubber tire train, a rail bus, a floating train (linear motor car), and the like, and includes a loop antenna 1T to 4T, a ground device 2, And on-vehicle device 3.

  The loop antennas 1T to 4T are provided along the train traveling path 5 with a distance d therebetween. The loop antennas 1T to 4T can be configured as, for example, parallel two-wire induction wires. The lengths of the loop antennas 1T to 4T along the train traveling path 5 are clearly determined when the loop antennas are laid. The arrangement interval d between the loop antennas is about several tens of centimeters.

  The ground device 2 and the on-board device 3 exchange information via any one of the loop antennas 1T to 4T and the on-board antenna 41, and in principle, those known from the past are used. it can. The ground device 2 has a transmission / reception function and a signal processing function. Specifically, the ground device 2 receives and decodes the signal S0 transmitted from the on-board device 3 of the train TR through any of the loop antennas 1T to 4T. The ATC signals S11 to S14 necessary for controlling the train TR are transmitted to the loop antennas 1T to 4T.

  The on-board device 3 also has a transmission / reception function and a signal processing function, and is provided in the train TR. The onboard device 3 receives and decodes the ATC signals S11 to S14 supplied from the ground device 2 to the loop antennas 1T to 4T through the onboard antenna 41. Furthermore, the speed information S2 from the speed counting means 42 is input to the on-board device 3. Examples of the speed counting means 42 include a speed generator or a tachometer.

  Among the loop antennas 1T to 4T, ATC signals transmitted from adjacent loop antennas have carrier frequencies set to different values. For example, the carrier frequency of the ATC signal S11 transmitted from the loop antenna 1T and the carrier frequency of the ATC signal S12 transmitted from the loop antenna 2T are set to different values fc1 and fc2. Furthermore, in the case of an Example, it is set so that the carrier frequency of the ATC signal received by the on-board device 3 may be alternately switched as the train TR sequentially travels through the loop antennas 1T to 4T. That is, the carrier frequencies of the ATC signals S11 to S14 are set to values fc1, fc2, fc1, and fc2, respectively. Taking numerical examples of the values fc1 and fc2, the value fc1 is 20 kHz and the value fc2 is 21 kHz.

  The transmission levels at which the loop antennas 1T to 4T transmit the ATC signals S11 to S14 to the vehicle upper side are set to the same level.

  The ATC signals S11 to S14 may be either analog or digital. As an example of the analog ATC signal, a signal wave obtained by amplitude-modulating a carrier wave having a predetermined frequency with a modulated wave having a frequency corresponding to train control information (for example, a train speed limit) can be cited.

  An example of a digital ATC signal is a signal wave obtained by modulating a carrier wave having a predetermined frequency with a digital code (for example, codes “0” and “1”). The digital code includes train control information. As a modulation method, frequency shift keying such as FSK and MSK (minimum shift keying) can be employed.

  In the above-described ground-to-vehicle information transmission apparatus according to the present invention, the loop antennas 1T to 4T are arranged along the train traveling path 5 with a distance d therebetween. Further, adjacent loop antennas, for example, loop antennas 1T and 2T, transmit ATC signals S11 and S12 set to different carrier frequencies (values fc1 and fc2) to the vehicle upper side.

  The on-board device 3 decodes the carrier frequencies of the ATC signals S11 to S14 received from the loop antennas 1T to 4T. For example, when the train TR is located on the loop antenna 1T, the on-board device 3 receives the ATC signal S11 from the loop antenna 1T and decodes the carrier frequency (value fc1) of the ATC signal S11.

  Consider a case where the train TR travels on the train travel path 5. First, since the train TR is positioned on the loop antenna 1T and before entering the boundary position P1 between the loop antennas 1T and 2T, the on-board device 3 receives only the ATC signal S11 from the loop antenna 1T. The carrier frequency of the ATC signal decoded by the on-board device 3 is a constant value fc1.

  Next, when the train TR enters the boundary position P1 between the loop antennas 1T and 2T, the on-board device 3 receives from the other loop antenna 2T instead of receiving the ATC signal S11 from the loop antenna 1T so far. The ATC signal S12 is received. Therefore, the carrier frequency of the ATC signal received by the on-board device 3 is switched from the value fc1 to the value fc2, and at this time, the on-board device 3 detects that the train TR is at the boundary position P1 between the loop antennas 1T and 2T. It is determined that it is located.

  The boundary position P1 between the loop antennas 1T and 2T is known in advance as kilometer information of the train travel path 5. Accordingly, on the vehicle upper side, by calculating the position of the train TR from the boundary position P1 between the loop antennas 1T and 2T based on the determination result that the train TR is determined to be located at the boundary position P1 between the loop antennas 1T and 2T. The accuracy of train position detection can be increased.

  Further, in the upper part of FIG. 1, a graph showing the relationship between the position of the train and the reception level of the ATC signal as seen on the upper side of the vehicle is shown. First, in the state before the train TR is positioned on the loop antenna 1T and enters the boundary position P1 between the loop antennas 1T and 2T, the distance between the loop antenna 1T and the on-board antenna 41 is constant. The reception level Lv is also a substantially constant value Lv1.

  Next, when the train TR enters the boundary position P1 between the loop antennas 1T and 2T, the on-board antenna 41 is separated from the loop antenna 1T, so the reception level Lv of the ATC signal decreases from the value Lv1 to the value Lv2. To do.

  In the on-board device 3 of the embodiment, when the reception level Lv of the ATC signal decreases and the carrier frequency of the ATC signal is switched from the value fc1 to the value fc2, the train TR is located at the boundary position P1 between the loop antennas 1T to 2T. It is determined that it is located at. That is, since the determination is performed based on both the reception level Lv of the ATC signal and the carrier frequency of the ATC signal, the reliability of the determination result can be improved.

  Further, the on-board device 3 of the embodiment calculates the position information S3 of the own train TR including the travel distance information from the speed information S2 input from the speed counting means 42, and the own train TR is placed inside the on-board device 3. Is stored. When the on-board device 3 determines that the train TR is located at the boundary position P1 between the loop antennas 1T and 2T, the on-board device 3 corrects the position information S3 of the own train TR based on the determination result. For example, if the boundary position P1 between the loop antennas 1T and 2T is about 1000 m, but the position information S3 of the train TR has an error of about 1010 km, the position information S3 of the train TR is set to about 1000 m. to correct. Therefore, the accuracy of the position information S3 of the train TR can be improved.

  By increasing the accuracy of the position information S3 of the train TR in this way, pattern control with high stop accuracy such as stopping the train TR at an accurate position becomes possible. Furthermore, overrun protection pattern control and erroneous passage pattern control can be realized.

  As described above, the boundary position P1 between the loop antennas 1T and 2T has been representatively described, but the determination of the train position and the train are similarly performed for the boundary positions P2 and P3 between the loop antennas (2T-3T) and (3T-4T). The position information is corrected.

  As the train TR travels on the train travel path 5, the train TR sequentially passes through the boundary positions P1, P2, and P3 between the loop antennas (1T-2T), (2T-3T), and (3T-4T). By correcting the position information S3 of the train TR every time it passes through the boundary positions P1, P2, and P3 between the loop antennas, the position information S3 of the train TR can be maintained with high accuracy over the entire train travel path 5. Become.

  In addition, when a signal wave obtained by modulating a carrier wave with a digital code is used as the ATC signals S11 to S14, a bit indicating the train traveling direction can be provided in the digital code of the ATC signal, and for distinguishing the train traveling direction. There is no need to use different carrier frequencies for ATC signals. Therefore, the carrier frequency of the ATC signals S11 to S14 can be arbitrarily set for each of the loop antennas 1T to 4T.

  While the present invention has been described with reference to the embodiment, it is needless to say that the present invention is not limited to this embodiment, and various modifications and changes can be made within the scope of the claims.

It is a figure explaining one Example of the ground-vehicle information transmission apparatus which concerns on this invention.

Explanation of symbols

1T to 4T Loop antenna 2 Ground device 3 On-vehicle device S11 to S14 ATC signal

Claims (4)

A ground-to-vehicle information transmission device including a plurality of loop antennas and an on-vehicle device,
The loop antennas are spaced apart from each other along the train traveling path, and adjacent loop antennas transmit ATC signals set to different carrier frequencies to the vehicle upper side,
The on-board device decodes the carrier frequency of the ATC signal received from the loop antenna, and determines that the own train is located on the boundary between the loop antennas when the carrier frequency of the ATC signal is switched.
Ground-to-vehicle information transmission device. The ground-to-vehicle information transmission device according to claim 1,
The on-board device determines that the own train is located on the boundary between the loop antennas when the reception level of the ATC signal decreases and the carrier frequency of the ATC signal is switched.
Ground-to-vehicle information transmission device. The ground-to-vehicle information transmission device according to claim 1 or 2,
The on-board device corrects the position information of the own train based on the determination result that the own train is determined to be located on the boundary between the loop antennas.
Ground-to-vehicle information transmission device. A ground-to-vehicle information transmission device according to any one of claims 1 to 3,
The loop antenna transmits an ATC signal which is a signal wave obtained by modulating a carrier wave with a digital code.
Ground-to-vehicle information transmission device.

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