JP4811097B2 - On-board antenna and automatic train stop system - Google Patents

Description

  The present invention relates to an on-board antenna used for transmission and reception in an on-board device used for mutual information transmission between a train and the ground in an automatic train stop system. The present invention also relates to an automatic train stop system using the on-board antenna.

  The automatic train stop system consists of an on-board device installed on the train and an on-ground device installed on the ground, and between the on-board antenna connected to the on-board device and the ground antenna connected to the ground device. It is a system that controls train operation by mutually transmitting information. Since a variable frequency antenna is used for low-frequency communication and a transponder antenna is used for high-frequency communication, the on-board antenna used for the on-board device must be equipped with an on-board antenna corresponding to each method. Must be installed.

Japanese Patent Laid-Open No. 10-278797 Introduction to Signals for Railway Electricians, Signal Series No.7 “ATS ATC” (published by Japan Railway Electrical Engineering Association), pages 51-53

  Conventionally, it has been said that when a variable frequency transmission type onboard antenna and a transponder type onboard antenna are installed close to each other and used, they cannot interfere with each other and transmit and receive. In particular, countermeasures for interference have been conventionally taken for high-frequency communication, but the frequency-dividing method for low-frequency communication has not been sufficient for countermeasures. In order to avoid mutual interference, it is necessary to sufficiently separate the low-frequency communication on-board antenna and the high-frequency communication on-board antenna. For example, in Non-Patent Document 1, it is necessary to install the antenna at a distance of 7 m or more. It is said that there is an on-board antenna for low-frequency communication and an on-board antenna for high-frequency communication on the front lower surface and center lower surface of the train. The on-board antenna for low-frequency communication and the on-board antenna for high-frequency communication are installed apart from each other, making it difficult to install in a limited space in the vehicle. There was a problem of inviting.

  The on-vehicle antenna according to the present invention includes a low-frequency communication coil composed of a first planar circular coil and a second planar circular coil, a high-frequency communication coil composed of a zero-shaped coil, and an electric power composed of an eight-shaped coil. An on-board antenna for an automatic train stop system equipped with a supply coil, arranged so that the center point of the low frequency communication coil, the center point of the high frequency communication coil, and the center point of the power supply coil overlap each other A center line of a low-frequency communication coil connecting the center point of the first planar circular coil and the center point of the second planar circular coil, and a high-frequency communication coil that divides the zero-shaped coil in line symmetry The center line and the center line of the power supply coil that vertically divides the figure 8 are arranged so as to overlap each other.

  The on-vehicle antenna according to the present invention includes a low-frequency communication coil composed of a first planar circular coil and a second planar circular coil, a high-frequency communication coil composed of a zero-shaped coil, and an electric power composed of an eight-shaped coil. An on-board antenna for an automatic train stop system equipped with a supply coil, arranged so that the center point of the low frequency communication coil, the center point of the high frequency communication coil, and the center point of the power supply coil overlap each other A center line of a low-frequency communication coil connecting the center point of the first planar circular coil and the center point of the second planar circular coil, and a high-frequency communication coil that divides the zero-shaped coil in line symmetry Since the center line and the center line of the power supply coil that vertically divides the figure 8 are arranged so as to overlap, the on-board antenna can be reduced in size and space can be saved.

Embodiment 1 FIG.
FIG. 1 is a diagram showing an outline of an automatic train stop system. The on-board antenna 702 provided in the on-board device is attached to the lower surface at the head of the train 701, and the ground antenna 703 of the ground device is attached in the track 704. The automatic train stop system includes an on-board device installed on the train 701 and a ground device installed on the ground, and includes an on-board antenna 702 connected to the on-board device and a ground antenna 703 connected to the ground device. It is a system that controls the train operation by transmitting information between each other.

  FIG. 2 is a schematic diagram of the low frequency communication coil of the on-board antenna 702. The low frequency communication coil 100 includes a transmission coil 101 and a reception coil 102. The transmission coil 101 and the reception coil 102 are each configured by winding a predetermined number of conductive wires with the same diameter. The transmitting coil 101 and the receiving coil 102 are superimposed within a predetermined range that does not hinder communication. L1 is a line passing through the center point O1 of the transmission coil 101 and the center point O2 of the reception coil 102, and is the center line of the low frequency communication coil 100. O3 is on the center line L1 of the low-frequency communication coil 100 and is at the same distance from the center point O1 of the transmission coil 101 and the center point O2 of the reception coil 102, and is the center point of the low-frequency communication coil 100. . L2 is a line segment passing through the center point O3 and orthogonal to the center line L1.

  The conventional coil for low frequency communication has been arranged so that the line segment L2 is parallel to the traveling direction of the train. On the other hand, in the present invention, the low frequency communication coil 100 is arranged so that the low frequency communication coil center line L1 is parallel to the traveling direction of the train 701. Therefore, the installation direction differs from the conventional low frequency communication coil by 90 degrees.

  The on-board antenna 702 uses the low-frequency communication coil 100 for low-frequency communication and performs communication by a so-called variable frequency method. The transmission coil 101 and the reception coil 102 are arranged so as to overlap each other so that the degree of coupling associated with mutual induction becomes low. The on-board device oscillates by itself using a low-frequency communication on-board antenna, and the oscillation frequency changes when the low-frequency communication on-board antenna and the ground antenna coil of the ground device are coupled. Information can be transmitted on the ground and on the vehicle by associating the transmission information with the oscillation frequency in advance.

  FIG. 3 is a schematic diagram of the high frequency communication coil of the on-vehicle antenna 702. The high-frequency communication coil 200 is configured by winding a predetermined number of conductive wires around an O-shape. This is a so-called zero-shaped coil (O-shaped coil). Here, although it is referred to as a letter “0” (a letter “O”), it is a rectangular coil or a square coil as shown in FIG. Here, although the high-frequency communication coil 200 is described as one coil for transmission and reception, it may be configured separately and divided into two for transmission coil and reception coil.

  L3 is a line that intersects perpendicularly with either of the pair of sides that are parallel to the high-frequency communication coil 200 and bisects the high-frequency communication coil 200, and is a center line of the high-frequency communication coil 200. O4 indicates the center point of the high-frequency communication coil 200. The high frequency communication coil 200 is arranged such that the center line L3 of the high frequency communication coil 200 is parallel to the traveling direction of the train 701. That is, the pair of sides of the rectangular coil is oriented in the traveling direction of the train 701, and the other pair of sides is installed so as to be perpendicular to the traveling direction.

  FIG. 4 is a schematic diagram of the power supply coil of the on-board antenna 702. The power supply coil 300 is configured by winding a predetermined number of conductive wires in an 8-shaped form. This is a so-called 8-shaped coil. Here, although referred to as a figure-eight shape, it simply refers to a structure in which conductive wires intersect at the center of the coil. For this reason, although referred to as a figure-eight shape, the four corners of the coil are perpendicular. O5 is the center point of the power supply coil at the intersection of the figure 8. L 4 is a line that passes through the intersection of the figure 8 and divides both figure 8 loops into two symmetrically lines, and is the center line of the power supply coil 300. Therefore, the center line L4 is a line that divides the figure 8 of the power supply coil 300 vertically into two loops. The power supply coil 300 is arranged so that the center line L4 of the power supply coil 300 is parallel to the traveling direction of the train.

  The on-vehicle antenna 702 uses the high-frequency communication coil 200 and the power supply coil 300 for high-frequency communication, and performs communication by a so-called transponder method. For high-frequency communication, a transponder is used to transmit digital information between the vehicle antenna 702 and the ground antenna 703. The transponder is a communication device composed of a transmitter (transmitter) and a responder (responder), and has a function of transmitting a large amount of information with high quality and high speed. Further, a power wave for supplying power is radiated from the power supply coil 300 in order to drive the ground device with no power supply.

  5, 6 and 7 are schematic diagrams for explaining the configuration of the on-board antenna, and are diagrams for explaining that there are various combinations in the configuration of the on-board antenna. In addition, although 702 and 400 are used as a part number of a vehicle-mounted antenna, both point to the same thing. The on-board antenna 702 is mainly used when explaining the function or role of the on-board antenna, while the on-board antenna 400 is only used mainly when explaining the internal structure of the on-board antenna.

  Moreover, in the figure, what attached | subjected the same code | symbol is the same or it corresponds, and this is common in the whole text of a specification. In order to avoid displaying the part number in a complicated manner, the part numbers are not shown in FIG. 5 and subsequent drawings. Further, the description of the constituent elements appearing in the whole specification is merely an example and is not limited to these descriptions.

  The on-vehicle antenna 400 includes a low frequency communication coil 100, a high frequency communication coil 200, and a power supply coil 300. In the figure, the center line L1 of the low frequency communication coil 100, the center line L3 of the high frequency communication coil 200, and the center line L4 of the power supply coil 300 are arranged so as to overlap each other. Further, the center point O3 of the low-frequency communication coil 100, the center point O4 of the high-frequency communication coil 200, and the center point O5 of the power supply coil 300 are arranged so as to overlap each other. For this reason, the on-board antenna 400 is disposed so that the surface of the low frequency communication coil 100, the surface of the high frequency communication coil 200, and the surface of the power supply coil 300 are parallel to each other.

  Here, what is important is that the center lines L1, L3, and L4 match when projected onto a predetermined plane, and the center points O3, O4, and O5 match when projected onto a predetermined plane. is there. Therefore, as shown in FIGS. 5 to 7, the sizes of the low-frequency communication coil 100, the high-frequency communication coil 200, and the power supply coil 300 may be different within the range of common sense.

  In addition, the low frequency communication coil 100, the high frequency communication coil 200, and the power supply coil 300 may be configured by means other than a conductive wire as long as they have equivalent performance. For example, you may comprise each coil using a printed circuit board. Alternatively, each coil may be formed in each layer using a multilayer printed board, and may be configured with a single printed board.

  Conventionally, interference countermeasures have been taken for signals that can be received by the high-frequency communication coil 200. On the other hand, sufficient interference countermeasures have not been taken for the low-frequency communication coil 100. Therefore, the countermeasure against interference in the low frequency communication coil 100 will be described below. This is because if the problem of interference in the low-frequency communication coil 100 is improved, the compact high-frequency antenna 400 can be realized by integrating the high-frequency communication coil 200 and the low-frequency communication coil 100.

  8, FIG. 9, FIG. 10, and FIG. 11 are conceptual diagrams showing the frequency spectrum and band elimination filter characteristics of a signal that can be received by the receiving coil 102 of the low frequency communication coil 100. FIG. The horizontal axis indicates the frequency, and the vertical axis indicates the frequency spectrum of the signal that can be received by the low frequency communication coil 100. 8 and 9 show a case where the center lines L1, L3, and L4 of the on-board antennas 400 and 702 match and the center points O3, O4, and O5 match. On the other hand, FIGS. 10 and 11 show a case where the center lines L1, L3, L4 of the on-board antennas 400, 702 substantially match and the center points O3, O4, O5 approximately match. Here, “substantially coincide” refers to the case where the center lines L1, L3, L4 are shifted, and the case where the center points O3, O4, O5 are shifted.

  The low frequency communication signal has a low frequency communication spectrum 501 in the band from 70 kHz to 130 kHz, the power supply signal has a power supply spectrum 502 and 507 in the band centered on 245 kHz, and the high frequency communication signal has a center at 1.7 kHz and 3.0 kHz. The high-frequency communication spectrum 503 exists as a spectrum peak in each band.

  In FIG. 8, the power supply spectrum 502 and the high-frequency communication spectrum 503 can be removed using a notch filter having the band elimination filter characteristic 504. Separately, as shown in FIG. 9, a notch filter having the characteristics of the band elimination filter characteristic 505 and a low-pass filter having the characteristics of the band elimination filter 506 are connected in two stages, and the power supply spectrum 502 and the high frequency communication spectrum are connected. 503 can be removed.

  Note that a band elimination filter that removes the power supply spectrum 502 and the high frequency communication spectrum 503 transmitted and received between the power supply coil 300 and the high frequency communication coil 200 at the output of the reception coil 102 of the low frequency communication coil 100 is provided. It may be attached.

  On the other hand, in FIG. 10 and FIG. 11 in which the center lines L1, L3, and L4 of the on-board antennas 400 and 702 substantially match and the center points O3, O4, and O5 substantially match, the low frequency communication spectrum 501 and the power A supply spectrum 507 and a high-frequency communication spectrum 503 are observed. Since the center lines L1, L3, and L4 are substantially coincident and the center points O3, O4, and O5 are substantially coincident, the power supply spectrum 507 is larger than the power supply spectrum 502.

  In FIG. 10, the power supply spectrum 507 and the high-frequency communication spectrum 503 can be removed using a notch filter having a band elimination filter characteristic 508. Separately, as shown in FIG. 11, the power supply spectrum 507 and the high-frequency communication spectrum are connected even if a notch filter having the characteristics of the band elimination filter 509 and a low pass filter having the characteristics of the band elimination filter 510 are connected in two stages. 503 can be removed. Thus, in the configuration of the on-board antenna 400 by using a band elimination filter or the like, the center lines L1, L3, L4 or the center points O3, O4, O5 of each coil interfere with low-frequency communication and high-frequency communication. It can be seen that they can be separated within a predetermined range.

  By providing interference removing means for removing interference with the output of the low frequency communication coil 100 by the high frequency communication coil 200 and the power supply coil 300, interference with the low frequency communication coil 100 can be removed.

  FIG. 12 is a diagram for explaining generation of magnetic flux. When a current flows through the power supply coil 300, a magnetic flux 601 is generated in the opposite direction in two loops configured in an 8-shape. Since the on-board antenna 400 of the present embodiment has a line-symmetric structure with respect to the center line L1, for example, the transmission coil 101 of the low frequency communication coil 100 is opposite in direction to the center line L1 and has an absolute value. Since the same magnetic flux 601 is generated, the total of the magnetic flux 601 is zero by canceling out both inside and outside the transmission coil 101. Since the on-board antenna 400 has a symmetrical structure with respect to the center line L1, similarly, the magnetic flux 601 cancels out also in the receiving coil 102 of the low frequency communication coil 100 and the high frequency communication coil 200. That is, the magnetic flux generated by the low frequency communication coil 100 and the magnetic flux 601 generated by the power supply coil 300 can be canceled out. Further, the magnetic flux generated in the high-frequency communication coil 200 and the magnetic flux 601 generated in the power supply coil 300 can cancel each other.

  According to the present embodiment, the power supply spectrum 502 is such that the sum of the magnetic fluxes 601 generated by the power supply coil 300 passing through the low frequency communication coil 100 does not affect the operation and communication of the on-board device. The high-frequency communication coil 200 and the power supply coil 300 are arranged so as to decrease. Thereby, low frequency communication and high frequency communication can be performed simultaneously.

  As described above, the on-board antenna is composed of the low-frequency communication coil including the first planar circular coil and the second planar circular coil, the high-frequency communication coil including the zero-shaped coil, and the 8-shaped coil. An on-board antenna for an automatic train stop system with a power supply coil so that the center point of the low frequency communication coil, the center point of the high frequency communication coil, and the center point of the power supply coil overlap. The center line of the low frequency communication coil arranged and connecting the center point of the first planar circular coil and the center point of the second planar circular coil, and the coil for high frequency communication that divides the zero-shaped coil in line symmetry Is arranged so that the center line of the power supply coil that divides the figure 8 vertically is overlapped, so that the on-board antenna can be reduced in size and space can be saved.

  In addition, the on-board antenna can be further miniaturized and space-saving can be achieved by arranging the surface of the coil for low frequency communication, the surface of the coil for high frequency communication and the surface of the coil for power supply in parallel. Can do.

  Further, the magnetic flux generated in the low frequency communication coil and the magnetic flux generated in the power supply coil cancel each other, and the magnetic flux generated in the high frequency communication coil and the magnetic flux generated in the power supply coil can cancel each other.

  Further, since the interference removing means for removing the interference with the output of the low frequency communication coil by the high frequency communication coil and the power supply coil is provided, the interference to the low frequency communication coil can be removed.

  Furthermore, the center line of the coil for low-frequency communication can be arranged in parallel with the traveling direction of the train, so that the antennas on the vehicle can be concentrated in one place, which can reduce the size and save space. Can do.

  By adopting the automatic train stop system using the on-board antenna of the present embodiment, it becomes possible to deal with the variable speed method and the transponder method with a single on-board antenna. Also, the cost can be reduced by downsizing and space saving.

It is a figure showing the outline of an automatic train stop system. It is the schematic of the coil for low frequency communication of a vehicle-mounted antenna. It is the schematic of the coil for high frequency communications of a vehicle-mounted antenna. It is the schematic of the coil for electric power supply of a vehicle-mounted antenna. It is the schematic for demonstrating the structure of a vehicle-mounted antenna. It is the schematic for demonstrating the structure of a vehicle-mounted antenna. It is the schematic for demonstrating the structure of a vehicle-mounted antenna. It is a conceptual diagram which shows a frequency spectrum and a band elimination filter characteristic. It is a conceptual diagram which shows a frequency spectrum and a band elimination filter characteristic. It is a conceptual diagram which shows a frequency spectrum and a band elimination filter characteristic. It is a conceptual diagram which shows a frequency spectrum and a band elimination filter characteristic. It is a figure for demonstrating generation | occurrence | production of magnetic flux.

Explanation of symbols

100 Coil for low frequency communication, 101 Transmitting coil, 102 Receiver coil, 200 Coil for high frequency communication, 300 Coil for power supply, 400 On-board antenna, 501 Low frequency communication spectrum, 502 Power supply spectrum, 503 High frequency communication spectrum,
504 Band elimination filter characteristics, 505 Band elimination filter characteristics, 506 Band elimination filter characteristics, 507 Power supply spectrum, 508 Band elimination filter characteristics, 509 Band elimination filter characteristics, 510 Band elimination filter characteristics, 601 Magnetic flux, 701 train, 702 On-vehicle Antenna, 703 Ground antenna, 704 orbit, O1 transmitting coil center point, O2 receiving coil center point, O3 low frequency communication coil center point, O4 high frequency communication coil center point, O5 power supply coil center point, L1 low frequency communication Coil center line, L2 Line orthogonal to coil center line for low frequency communication, L3 Coil center line for high frequency communication, L4 Coil center line for power supply.

Claims (6)

An automatic train comprising a low-frequency communication coil composed of a first planar circular coil and a second planar circular coil, a high-frequency communication coil composed of a zero-shaped coil, and a power supply coil composed of an eight-shaped coil An on-board antenna for a stop device,
The center point of the low-frequency communication coil, the center point of the high-frequency communication coil and the center point of the power supply coil are arranged to overlap,
A center line of the low-frequency communication coil connecting the center point of the first planar circular coil and the center point of the second planar circular coil, and high-frequency communication for dividing the zero-shaped coil line-symmetrically An on-vehicle antenna, wherein a center line of a coil and a center line of a power supply coil that divides the figure 8 vertically are overlapped. The on-vehicle antenna according to claim 1, wherein the surface of the low-frequency communication coil, the surface of the high-frequency communication coil, and the surface of the power supply coil are arranged in parallel. The magnetic flux generated in the low frequency communication coil and the magnetic flux generated in the power supply coil cancel each other.
The on-vehicle antenna according to claim 1 or 2, wherein the magnetic flux generated by the high-frequency communication coil and the magnetic flux generated by the power supply coil cancel each other. The on-vehicle antenna according to any one of claims 1 to 3, further comprising interference removing means for removing interference with an output of the low frequency communication coil by the high frequency communication coil and the power supply coil. The on-board antenna according to any one of claims 1 to 4, wherein the center line of the low-frequency communication coil is arranged in parallel with the traveling direction of the train. An automatic train stop system using the on-board antenna according to any one of claims 1 to 5.

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