JP2014076687A - Position detection system, and position detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive and simple position detection system and method by using specific small power radio.SOLUTION: A position detection system includes in a vehicle a GPS receiver 20 for positioning a position on the basis of a GPS signal to output the current position, a track data storage part 51 for storing coordinates of a plurality of section blocks set along a traveling track as track data, a traveling position specification part 42 for specifying a section block with the vehicle located on the basis of the current position and the track data, a vehicle information storage part 52 for storing vehicle information for specifying the vehicle, a radio frame generation part 43 for generating a radio frame including the specified section block and the vehicle information in the case of determining that the vehicle enters a new section block, and an in-vehicle radio device 60 for transmitting a radio frame by using a band of the specific small power radio. An incoming radio device and an outgoing radio device for receiving a radio frame are respectively installed in each station 70.

Description

  The present invention relates to a position detection system and a position detection method for detecting a position where a vehicle travels in transportation such as an LRT (Light Rail Transit) or a route bus.

  An on-board device having a GPS receiver for positioning the position of the vehicle and an on-vehicle wireless transmission unit for transmitting the positioning position measured by the GPS receiver to the central management device is mounted on the vehicle. A position detection system that grasps a detection section where a vehicle is located has been proposed (see, for example, Patent Document 1).

JP 2003-237582 A

  However, in the prior art, it is necessary to wirelessly transmit the positioning position directly from the on-board device to the central management device, and in order to detect the vehicle entering a new detection zone, the vehicle mounted on the vehicle Since the positioning position must always be transmitted from the upper device, it is necessary to adopt a high-speed and large-scale wireless network with a long communicable distance requiring a license, and the construction of a position detection system is expensive and complicated There was a problem of becoming.

  The present invention has been made in view of such problems, and an object thereof is to provide an inexpensive and simple position detection system and position detection method using a specific low-power radio.

A position detection system according to the present invention is a position detection system that detects the position of a vehicle traveling on a traveling route, and measures a position based on a GPS signal and outputs a current position; Route data storage means for storing, as route data, coordinates of a plurality of section blocks set along the road, and traveling position specifying means for specifying the section block where the vehicle is located based on the current position and the route data; Vehicle information storage means for storing vehicle information for specifying the vehicle, and the section block and vehicle information specified by the travel position specifying means when it is determined that the vehicle has entered a new section block. A radio frame generating means for generating a radio frame including the radio frame, and the radio frame generated by the radio frame generating means. The vehicle includes a vehicle-mounted wireless device that transmits using a low-power wireless band, and a plurality of wireless devices that receive wireless frames from the vehicle-mounted wireless device are arranged on the travel route. .
Furthermore, in the position detection system according to the present invention, a channel assigned to the identified radio is specified by identifying the radio closest to the current position among the plurality of radios arranged on the travel route. And a radio frame transmitting means for transmitting the radio frame by the in-vehicle wireless device.
Furthermore, in the position detection system according to the present invention, the radio frame transmission means specifies a transmission output according to a distance between the current position and the radio apparatus closest to the current position, and the in-vehicle radio apparatus uses the specified transmission output. The wireless frame is transmitted.
Furthermore, in the position detection system according to the present invention, the radio is composed of an uplink radio and a downlink radio, and the radio frame transmission means is configured to travel the vehicle based on a travel history based on the current position. Specifying a direction, using the first channel assigned to the uplink radio or the downlink radio corresponding to the specified traveling direction, causing the in-vehicle radio to transmit the radio frame, If the radio frame cannot be transmitted even if the transmission using the channel is performed a plurality of times, the second channel assigned to the downlink radio or the uplink radio corresponding to the direction opposite to the specified traveling direction is selected. And the wireless frame is transmitted by the in-vehicle wireless device. .
Further, the position detection method according to the present invention is a position detection method for detecting the position of a vehicle traveling on a traveling route, wherein the current position is determined based on a GPS signal by a GPS receiver in the vehicle. The position is output, and the coordinates of a plurality of section blocks set along the traveling route are stored as route data in the route data storage means, and the vehicle is positioned based on the current position and the route data. A section block is specified, vehicle information for specifying the vehicle is stored in a vehicle information storage unit, a radio frame including the specified section block and the vehicle information is generated, and the generated radio frame is used as an in-vehicle radio. A specific low-power radio band is transmitted by the machine, and a radio frame from the in-vehicle radio is transmitted by a plurality of radios arranged on the travel route. Characterized by trust.

  In the position detection system and the position detection method of the present invention, since the section block is specified on the vehicle side, there is no need to always transmit the current position from the vehicle, and only when the vehicle enters a new section block, the radio frame is transmitted. Therefore, it is possible to reduce the communication traffic, and it is possible to construct an inexpensive and simple position detection system using a specific low power radio with a short communicable distance and a low speed. Further, since the radio frame is transmitted by specifying the transmission output according to the distance to the radio device closest to the current position, it is possible to prevent interference when transmitting the radio frame.

It is a system configuration figure of an embodiment of a position detection system concerning the present invention. It is a block diagram which shows the structure of the vehicle-mounted apparatus shown in FIG. It is a figure which shows the example of a surplus length block arrange | positioned at the travel route on which the vehicle shown in FIG. 1 drive | works. It is a figure which shows the example of route data memorize | stored in the route data memory | storage part shown in FIG. It is a figure which shows the example of a channel used with the vehicle-mounted radio | wireless machine shown in FIG. 1, an uplink radio, and a downlink radio. It is a figure which shows the example of channel information memorize | stored as radio | wireless information in the radio | wireless information storage part shown in FIG. It is a figure which shows the example of transmission output information memorize | stored as radio | wireless information in the radio | wireless information storage part shown in FIG. It is a figure which shows the driving history example memorize | stored in the driving history memory | storage part shown in FIG. It is explanatory drawing for demonstrating the extra length block specific operation | movement by the driving | running | working position specific | specification part shown in FIG. It is explanatory drawing for demonstrating the extra length block specific operation | movement by the driving | running | working position specific | specification part shown in FIG. 3 is a flowchart for explaining a radio frame generation operation by a radio frame generation unit shown in FIG. 2. 3 is a flowchart for explaining a radio frame transmission operation by a radio frame transmission unit shown in FIG. 2. FIG. 3 is an explanatory diagram for describing a radio frame transmission operation by a radio frame transmission unit illustrated in FIG. 2.

  Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

  The position detection system according to the present embodiment is a system that detects the position of a traveling vehicle in a transportation system such as an LRT (Light Rail Transit) or a route bus that travels on a predetermined traveling route, see FIG. Then, the GPS receiver 20, the in-vehicle device 30 and the in-vehicle radio 60 installed in the traveling vehicle 10, and the up radio 71 and the down radio 72 installed in the station 70 where the vehicle 10 stops, respectively. The central management device 81 is installed in a management room 80 that manages the operation of the vehicle 10. Further, the upstream wireless device 71 and the downstream wireless device 72 are connected to the central management device 81 via the optical line 90 via an optical I / F 91 that is an interface with the optical line 90.

  The GPS receiver 20 receives GPS signals from a plurality of GPS satellites via a GPS antenna 21 installed on the roof of the vehicle 10 and measures the current position (latitude, longitude) based on the received GPS signals. And outputs the current position (latitude, longitude) as a positioning position. The GPS receiver 20 is configured to execute positioning every predetermined time and output a positioning position. Note that the timing at which the GPS receiver 20 executes positioning and outputs the positioning position may be set in advance, or may be configured to be settable by the user.

  The in-vehicle device 30 is an information processing device such as a personal computer, and the control unit 40 includes a storage unit 50, a GPS I / F 31 that is an interface with the GPS receiver 20, and a wireless I that is an interface with the in-vehicle wireless device 60. / F32 and an input unit 33 such as a mouse or a keyboard.

  The control unit 40 is an information processing unit such as a microcomputer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like. The ROM and the storage unit 50 store a control program for performing operation control of the in-vehicle device 30. The CPU of the control unit 40 reads out the control program stored in the ROM or the storage unit 50 and develops the control program in the RAM, thereby allowing the positioning position receiving unit 41, the traveling position specifying unit 42 shown in FIG. It functions as a radio frame generation unit 43 and a radio frame transmission unit 44, respectively.

  The storage unit 50 is a storage unit such as a semiconductor memory or an HDD (Hard Disk Drive), and includes a route data storage unit 51 that stores the route data illustrated in FIG. 2, a vehicle information storage unit 52 that stores vehicle information, and a wireless It functions as a wireless information storage unit 53 that stores information and a travel history storage unit 54 that stores a travel history.

  The positioning position receiving unit 41 receives the positioning position from the GPS receiver 20 via the GPS I / F 31 and outputs it to the traveling position specifying unit 42.

The route data storage unit 51 stores route data obtained by blocking travel routes. A plurality of blocks (hereinafter referred to as surplus length blocks) indicated by dotted lines in FIG. 3A are set on the travel route on which the vehicle 10 travels, and different block names are assigned to the surplus length blocks, respectively. Yes. The surplus length block set for the station 70 has “TOO” representing the station 70, and the surplus length block set for the route between the stations 70 has “ROO” representing the route. Has been granted. The surplus length block is a rectangular area, and one side of adjacent surplus length blocks is shared and continuously arranged along the travel route. Further, referring to FIG. 3B, section blocks are set in which extra length blocks set on the route between the stations 70 are grouped. The section block is a block that can be set by the user, and when it is desired to detect the position of the vehicle 10 in detail, a small number of extra-length blocks may be grouped, and the position of the vehicle 10 may be roughly detected. In this case, a large number of extra-length blocks may be grouped. The route data is data representing a surplus length block and a section block obtained by grouping the surplus length blocks. Referring to FIG. 4, “surplus length block name”, “section block name”, and surplus length block It consists of four vertex coordinates (latitude / longitude) of points a to d. In FIG. 4,
“Txxx” and “Rxxx” are “extra-length block names”, “Yxxx” are “section block names”, “axxx”, “bxxx”. "," Cxxx "and" dxxx "are the coordinates (latitudes) of the four vertices a, b, c and d in the extra length blocks" Txxx "and" Rxxx ". / Longitude). In the present embodiment, as shown in FIG. 4, the points a and c, and the points b and d of adjacent extra-length blocks have common vertex coordinates (latitude / longitude). Accordingly, either the points a and b or the points c and d can be omitted in the route data. Further, the shape of each extra-length block does not have to be the same as shown in FIG. 3A, and the width and length can be adjusted by reflecting an error of GPS positioning or the like.

  The traveling position specifying unit 42 compares the positioning position input from the positioning position receiving unit 41 with the route data stored in the route data storage unit 51 to specify the extra length block where the vehicle 10 is located. At the same time, the section block to which the specified extra length block belongs is specified. The extra length block specifying operation by the travel position specifying unit 42 will be described later. The travel position specifying unit 42 outputs the “section block name” of the specified section block to the radio frame generation unit 43 and also stores the “extra length block name” of the specified extra length block in the travel history storage unit 54 as a travel history. Remember.

  The vehicle information storage unit 52 stores, as vehicle information, a vehicle ID that identifies the vehicle 10 and a crew member ID that identifies a crew member. The vehicle ID and the crew ID may be input by the user from the input unit 33. The input unit 33 is provided with a connection port of an external storage medium such as an IC card, and the external storage medium in which the vehicle ID and the crew ID are stored. May be connected to the connection port and input. In the case where a connection port for an external storage medium is provided, the external storage medium itself can function as the vehicle information storage unit 52.

  The radio frame generation unit 43 determines whether or not the vehicle 10 has entered a new section block. If the radio frame generation unit 43 determines that the vehicle 10 has entered a new section block, the radio frame generation unit 43 transmits a radio frame to be transmitted to the central management device 81. Generate. In the radio frame generated by the radio frame generation unit 43, the vehicle ID and crew ID stored in the vehicle information storage unit 52 as vehicle information specifying the vehicle 10, and the position information specifying the section block where the vehicle 10 is located The “section block name” input from the travel position specifying unit 42 is included. In addition to the vehicle information and position information, various data desired by the user can be added to the radio frame. The radio frame generation operation by the radio frame generation unit 43 will be described later.

  The in-vehicle wireless device 60, the upstream wireless device 71, and the downstream wireless device 72 are wireless devices that satisfy certain conditions defined by the Ministry of Internal Affairs and Communications. This is a low power radio that transmits a radio frame using a band, for example, a 429 MHz band, and is provided with a plurality of channels. In the present embodiment, seven channels are provided as shown in FIG. 5, and the in-vehicle wireless device 60 has a function of transmitting a wireless frame on any of the seven channels. In addition, as shown in FIG. 6, a specific channel is assigned to each upstream station 71 in the uplink radio 71 and the downlink radio 72. FIG. 6 shows an example in which ten stations 70 having more than ½ of the number of channels exist on the travel route, and therefore the upstream radio 71 and the downstream radio of the stations 70 having the same channel but different. Used in machine 72. In addition, since the communicable distance of a low-power radio using a specific low-power radio band, for example, 429 MHz band, is about 2 km at the maximum, the same channel is used in the station 70 that is sufficiently far away from the communicable distance. However, no problem occurs.

  The wireless information storage unit 53 stores channel information indicating a channel for transmitting a wireless frame and transmission output information indicating a transmission output for transmitting the wireless frame as wireless information. As the channel information, as shown in FIG. 6, channels assigned to the uplink radio 71 and the downlink radio 72 installed in each station 70 existing on the travel route are set. As the transmission output information, as shown in FIG. 7, a transmission output corresponding to the distance between the vehicle 10 and the station 70 that transmits the radio frame is set.

  As illustrated in FIG. 8, the travel history storage unit 54 sequentially stores the “block name” input from the travel position specifying unit 42 and the input time as a travel history. The period for storing the “block name” of the extra-length block as the travel history is arbitrary, but at least the “block names” of a plurality of extra-length blocks need to be stored. In the travel history shown in FIG. 8, it is understood that the extra length block where the vehicle 10 is located is specified every 0.5 seconds, and in 13h20m17s00, the extra length block where the vehicle 10 is located is not specified. I understand.

  When a radio frame is generated by the radio frame generation unit 43, the radio frame transmission unit 44 stores the travel history stored in the travel history storage unit 54, the radio information stored in the radio information storage unit 53, the route Based on the route data stored in the data storage unit 51, the channel for transmitting the radio frame and the transmission output are specified, and the specified channel and the transmission output are determined together with the radio frame generated by the radio frame generation unit 43. The wireless frame is output to the in-vehicle wireless device 60 via the wireless I / F, and the radio frame is transmitted with the specified transmission output using the channel specified by the in-vehicle wireless device 60. The radio frame transmission operation by the radio frame transmission unit 44 will be described later.

  The radio frame transmitted by the in-vehicle wireless device 60 of the vehicle 10 is received by the upstream wireless device 71 via the antenna 711 or the downstream wireless device 72 via the antenna 721, and the upstream wireless device 71 and the downstream wireless device. 72 transmits the received radio frame to the central management apparatus 81 via the optical line 90. As a result, the central management device 81 collects the position information (section block where the vehicle 10 is located) of all the vehicles 10 traveling on the traveling route.

  The central management device 81 is an information processing device that operates by program control, and generates operation information of the vehicle 10 by receiving radio frames from all the vehicles 10 traveling on the traveling route, and the generated operation information is The data is output to a monitor (not shown) installed in the management room 80 or the station 70, or published on the web via an Internet line (not shown). It can also be output to an electronic interlocking device or guide device (not shown).

Next, the extra length block specifying operation by the travel position specifying unit 42 will be described in detail with reference to FIGS. 9 and 10.
When the positioning position is input from the positioning position receiving unit 41, the traveling position specifying unit 42 sets the longitude as the X axis and the latitude as the Y axis, and stores each extra length block stored as the route data in the route data storage unit 51. The maximum and minimum values of the X coordinate and the Y coordinate are calculated as the maximum and minimum values, and the X coordinate maximum and minimum values and the Y coordinate are input into the outer frame set by the maximum and minimum values. It is determined whether or not the determined positioning position is included, and the extra length block including the positioning position input in the outer frame is extracted as a candidate block. For example, in the case of the extra length block “R033” shown in FIG. 9, the longitude of the vertex b is the maximum value of the X coordinate, the longitude of the vertex c is the minimum value of the X coordinate, and the latitude of the vertex a is the maximum of the Y coordinate. As the value, the latitude of the vertex d is calculated as the maximum value of the Y coordinate, the outer frame indicated by the alternate long and short dash line in FIG. 9 is set, and the input positioning position is point A, point B, or point C. The extra-length block “R033” is extracted as a candidate block. The number of candidate blocks is not limited to one. For example, when the input positioning position is point C, the extra length block “T903” is also extracted as a candidate block. In addition, the above-described candidate blocks may be determined for all surplus length blocks, but based on the travel history stored in the travel history storage unit 54, The amount of processing can be reduced by performing the above-described determination only on the extra-length block arranged around the extra-length block. Further, the traveling direction of the vehicle 10 is determined based on the traveling history stored in the traveling history storage unit 54, and the surplus length block specified earlier is arranged on the traveling direction side of the vehicle 10 of the surplus length block. The amount of processing can be reduced even if the above-mentioned determination is performed only for the extra-length block.

  In the case of the extra length block “R033” shown in FIG. 9, even the point B where the input positioning position is not included in the extra length block is extracted as a candidate block. Accordingly, the traveling position specifying unit 42 determines whether or not the input positioning position is included in each extra length block extracted as a candidate block, and determines the extra length block including the input positioning position as the vehicle. It is specified as a surplus block in which 10 is located. First, as illustrated in FIG. 10, the traveling position specifying unit 42 calculates a point Z where the X coordinate of the input positioning position and the four sides of the extra length block intersect, and the Y of the calculated points Z is calculated. When the input positioning position is located on a line segment connecting two points having smaller coordinates, it is determined that the input positioning position is included in the extra length block. As shown in FIG. 10, when the input positioning position is point A (Xa, Ya), point Z1 (Xa, Y1) and point Z2 (Xa, Y2) are calculated, and Y1 <Ya <Y2 Therefore, the point A (Xa, Ya) is located on the line segment connecting the point Z1 (Xa, Y1) and the point Z2 (Xa, Y2). Accordingly, it is determined that the input positioning position is included in the extra length block “R033”, and the traveling position specifying unit 42 specifies the extra length block “R033” where the vehicle 10 is located and specifies The section block “Y006” to which the extra length block belongs is specified, and the section block name “Y006” is output to the radio frame generation unit 43. On the other hand, when the input positioning position is point B (Xb, Yb), point Z3 (Xb, Y3) and point Z4 (Xb, Y4) are calculated, and since Yb <Y3 <Y4, point Point B (Xb, Yb) is not located on the line segment connecting Z3 (Xb, Y3) and point Z4 (Xb, Y4). Accordingly, it is determined that the positioning position input in the extra length block “R033” is not included, and the traveling position specifying unit 42 does not specify the extra length block in which the vehicle 10 is located and performs the specific operation. End. In the present embodiment, it is configured to determine whether or not the input positioning position is included in the extra length block with reference to the X coordinate of the input positioning position. You may comprise so that it may determine whether the positioning position input in the extra length block is contained on the basis of the Y coordinate of a position.

  In addition, since the route data used in the present embodiment has one side of the adjacent extra length block in common, when the positioning position is located on the side of the extra length block, two extra lengths are used. A block may be identified. In this case, one of the two specified extra length blocks may be selected, or the extra block specified earlier may be selected.

Next, a radio frame generation operation by the radio frame generation unit 43 will be described in detail with reference to FIG.
Referring to FIG. 11, the radio frame generation unit 43 monitors the input of “section block name” from the travel position specifying unit 42 (step A1). When the “section block name” is input from the travel position specifying unit 42 in step A1, the radio frame generation unit 43 determines whether or not it is a new “section block name” (step A2), and the new “section block name”. If it is not “name”, that is, if it is the same as the “section block name” input last time, the process returns to step A1.

  If it is a new “section block name” in step A 2, that is, if it is different from the previously input “section block name”, the radio frame generation unit 43 sends the next “section block name” from the travel position specifying unit 42. The input of “name” is monitored (step A3). When “section block name” is input from the travel position specifying unit 42 in step A3, the radio frame generation unit 43 determines whether or not the “section block name” is the same as the previous time (step A4). If it is not “section block name”, that is, if it is different from the previously input “section block name”, the process returns to step A1.

  If it is the same “section block name” as the previous time in step A4, that is, if it is the same as the “section block name” input last time, that is, the new “section block name” input in step A1 is again the travel position. When specified and input by the specifying unit 42, the radio frame generating unit 43 determines that the vehicle 10 has entered a new section block, and the vehicle ID and crew ID stored in the vehicle information storage unit 52. And a “frame block name” input from the travel position specifying unit 42 is generated. Thus, in this embodiment, when a new “section block name” is input and the “section block name” is continuously input, it is determined that the vehicle 10 has entered a new section block. It is configured to. Note that the number of consecutive times is not limited to two and may be three or more.

Next, a radio frame transmission operation by the radio frame transmission unit 44 will be described in detail with reference to FIGS. 12 and 13.
Referring to FIG. 12, the radio frame transmitter 44 monitors the generation of radio frames by the radio frame generator 43 (step B1). When the radio frame is generated by the radio frame generation unit 43 in step B1, the radio frame transmission unit 44 transmits the travel history stored in the travel history storage unit 54 and the route data stored in the route data storage unit 51. Based on the above, the nearest station 70 is specified (step B2), and the traveling direction of the vehicle 10 is specified (step B3).

  In the case of the travel history as shown in FIG. 8, it can be seen that the vehicle 10 is located in the extra length block “R041”, and the radio frame transmitting unit 44 determines the number of blocks to the C station and the number of blocks to the D station. , The station 70 with a small number of blocks is identified as the nearest station 70. When the extra length block is arranged as shown in the upper part of FIG. 13 and the section block is set as shown in the lower part, and the vehicle 10 is positioned in the extra block “R041”, the number of blocks up to station C However, there are 9 blocks, and the number of blocks to D station is 7 blocks. Therefore, the radio frame transmission unit 44 identifies the C station as the nearest station 70. Note that the station 70 with the shortest distance may be specified by calculating the distance from the positioning position to the station 70 without comparing with the number of blocks.

  Further, in the case of the travel history as shown in FIG. 8, it can be seen that the vehicle 10 has moved from the extra length block “R040” to the extra length block “R041”. It can be seen that the traveling direction is “up” shown in FIG.

  Next, the radio frame transmitting unit 44 determines whether the uplink radio 71 and the downlink radio 72 installed at the station 70 identified in step B2 based on the channel information stored in the radio information storage unit 53. Among them, the one corresponding to the traveling direction specified in step B3 is specified as the first channel for transmitting the radio frame (step B4), and based on the transmission output information stored in the radio information storage unit 53 Then, the transmission output for transmitting the radio frame corresponding to the distance to the station 70 specified in step B2 is specified (step B5).

  When station C is identified in step B2, the traveling direction is identified as "up" in step B3, and channel information as shown in FIG. 6 is stored as wireless information in the wireless information storage unit 53, the wireless frame The transmission unit 44 identifies “CH3” as the first channel for transmitting the radio frame. Further, the number of blocks (distance) to the station C identified in step B2 is 9 blocks as shown in FIG. 13, and transmission output information as shown in FIG. 6 is stored as wireless information in the wireless information storage unit 53. If so, the radio frame transmission unit 44 specifies 7 mW as the transmission output for transmitting the line frame.

  Next, the radio frame transmitting unit 44 outputs the first channel specified in step B4 and the transmission output specified in step B5 to the in-vehicle wireless device 60 via the wireless I / F, and is specified by the in-vehicle wireless device 60. Using the first channel, a radio frame is transmitted with the specified transmission output (step B6). As a result, the radio frame is installed at the nearest station 70 from the vehicle 10, and the station closest to the vehicle 10 with respect to either the up radio 71 or the down radio 72 corresponding to the traveling direction of the vehicle 10. It is transmitted with a transmission output corresponding to the distance to 70.

  Next, the radio frame transmission unit 44 monitors reception of the confirmation response (step B7), and ends the radio frame transmission operation when receiving the confirmation response within a predetermined time. If the confirmation response is not received within the predetermined time in step B7, the radio frame transmission unit 44 determines whether or not the transmission of the radio frame is the Nth preset time in the current radio frame transmission operation (step S7). B8) If it is not the Nth time, the process returns to step B6 to transmit the radio frame again using the first channel. Thereby, when the confirmation response cannot be received, the transmission of the radio frame using the first channel is performed N times.

  In the case of the Nth time in step B8, the radio frame transmission unit 44, based on the channel information stored in the radio information storage unit 53, the uplink radio 71 installed in the station 70 identified in step B2. And the downlink radio device 72, the second channel for transmitting the radio frame is specified for the one corresponding to the direction opposite to the traveling direction specified in step B3 (step B9). Then, the radio frame transmitting unit 44 outputs the two channels identified in step B9 and the transmission output identified in step B5 to the in-vehicle wireless device 60 via the wireless I / F, and the first specified by the in-vehicle wireless device 60. A radio frame is transmitted with the specified transmission output using the channel 2 (step B10). As a result, the radio frame is installed at the nearest station 70 from the vehicle 10, and the station closest to the vehicle 10 with respect to either the up radio 71 or the down radio 72 corresponding to the traveling direction of the vehicle 10. It is transmitted with a transmission output corresponding to the distance to 70.

  Next, the radio frame transmission unit 44 monitors reception of the confirmation response (step B11), and ends the radio frame transmission operation when receiving the confirmation response within a predetermined time. When the confirmation response is not received within the predetermined time in step B11, the radio frame transmission unit 44 outputs a transmission error indicating that the radio frame could not be transmitted to the radio frame generation unit 43 (step B12).

  The radio frame generation unit 43 to which a transmission error is input from the radio frame transmission unit 44 receives the “section block name” from the travel position specification unit 42 after a preset time has elapsed regardless of the above-described radio frame operation. Is input, a radio frame is generated. That is, since a radio frame that should have been transmitted from the vehicle 10 was not transmitted due to a transmission error, the radio frame generation unit 43 generates a radio frame without determining that the vehicle 10 has entered a new section block. Then, transmission is tried again by the radio frame transmission unit 44.

  The uplink radio 71 and the downlink radio 72 are not necessarily installed at the station 70, and can be installed at any position other than the station 70. In this case, the radio frame transmitting unit 44 Thus, the closest uplink radio 71 and downlink radio 72 are specified.

As described above, in the present embodiment, the GPS receiver 20 that measures the position based on the GPS signal and outputs the current position, and the coordinates of the plurality of section blocks set along the travel route are used as route data. A route data storage unit 51 for storing the vehicle, a travel position specifying unit 42 for specifying a section block where the vehicle is located based on the current position and the route data, and a vehicle information storage unit 52 for storing vehicle information for specifying the vehicle 10. A radio frame generating unit 43 that generates a radio frame including the section block specified by the traveling position specifying unit 42 and vehicle information when it is determined that the vehicle 10 has entered a new section block; The vehicle 10 includes an in-vehicle radio 60 that transmits the radio frame generated by the generation unit 43 using a specific low-power radio band, and the in-vehicle radio Radio 71 and the downlink radio apparatus 72 for uplink receiving a radio frame are respectively installed in each station 70 of the running route from 0. With this configuration,
Since the section block is specified on the vehicle 10 side, it is not always necessary to transmit the current position from the vehicle 10, and it is sufficient to transmit a radio frame only when the vehicle 10 enters a new section block. This is advantageous in that an inexpensive and simple position detection system can be constructed using a specific low-power radio with a short communicable distance and a low speed.

  Further, according to the present embodiment, among the uplink radio 71 and the downlink radio 72 installed at each station 70, the uplink radio 71 and the downlink radio 72 closest to the current position are specified. In addition, a radio frame transmission unit 44 that transmits a radio frame by the in-vehicle radio 60 using the channels assigned to the specified uplink radio 71 and downlink radio 72 is provided. With this configuration, the radio frame can be reliably transmitted to the uplink radio 71 and the downlink radio 72 within the communicable distance.

  Further, according to the present embodiment, the radio frame transmission unit 44 identifies the transmission output according to the distance between the uplink radio 71 and the downlink radio 72 that are closest to the current position, and uses the identified transmission output. The in-vehicle wireless device 60 is configured to transmit a wireless frame. With this configuration, it is possible to prevent interference when transmitting a radio frame.

  Further, according to the present embodiment, the radio frame transmission unit 44 identifies the traveling direction of the vehicle 10 based on the traveling history based on the current position, and the uplink radio 71 or the downlink radio corresponding to the identified traveling direction. When the in-vehicle wireless device 60 transmits a radio frame using the first channel assigned to 72 and the radio frame cannot be transmitted even if transmission using the first channel is performed a plurality of times, the specified travel direction The in-vehicle radio device 60 is configured to transmit a radio frame using the second channel assigned to the downlink radio device 72 or the uplink radio device 71 corresponding to the opposite direction. As a result, the priority order for receiving radio frames from the up and down vehicles 10 can be set for the up radio 71 and the down radio 72, and radio frames from the vehicles 10 can be reliably received. it can.

  Note that the present invention is not limited to the above-described embodiments, and it is obvious that the embodiments can be appropriately changed within the scope of the technical idea of the present invention. In addition, the number, position, shape, and the like of the constituent members are not limited to the above-described embodiment, and can be set to a suitable number, position, shape, and the like in practicing the present invention. In each figure, the same numerals are given to the same component.

DESCRIPTION OF SYMBOLS 10 Vehicle 20 GPS receiver 21 GPS antenna 30 In-vehicle apparatus 31 GPS I / F
32 Wireless I / F
DESCRIPTION OF SYMBOLS 33 Input part 40 Control part 41 Positioning position receiving part 42 Traveling position specific | specification part 43 Radio | wireless frame production | generation part 44 Radio | wireless frame transmission part 50 Memory | storage part 51 Route data memory | storage part 52 Vehicle information memory | storage part 53 Radio | wireless information memory | storage part 54 Traveling history memory | storage part 60 In-vehicle radio 70 Station 71 Up radio 72 Down radio 80 Management room 81 Central management device 90 Optical line 91 Optical I / F

Claims (5)

A position detection system for detecting the position of a vehicle traveling on a travel route,
A GPS receiver that measures the position based on the GPS signal and outputs the current position;
Route data storage means for storing the coordinates of a plurality of section blocks set along the traveling route as route data;
Travel position specifying means for specifying the section block where the vehicle is located based on the current position and the route data;
Vehicle information storage means for storing vehicle information for identifying the vehicle;
A radio frame generating means for generating a radio frame including the section block specified by the travel position specifying means and the vehicle information when it is determined that the vehicle has entered a new section block;
The vehicle includes an in-vehicle wireless device that transmits the wireless frame generated by the wireless frame generating unit using a specific low power wireless band,
A position detection system, wherein a plurality of wireless devices that receive wireless frames from the in-vehicle wireless device are arranged on the travel route.   Among the plurality of wireless devices arranged on the travel route, the wireless device closest to the current position is identified, and the wireless frame is transmitted by the in-vehicle wireless device using a channel assigned to the identified wireless device. The position detection system according to claim 1, further comprising: a wireless frame transmission means for transmitting   The radio frame transmission means identifies a transmission output according to a distance between the current position and the radio apparatus closest to the current position, and causes the in-vehicle radio apparatus to transmit the radio frame with the specified transmission output. Item 3. The position detection system according to Item 1 or 2. The radio is composed of an uplink radio and a downlink radio,
The radio frame transmitting means identifies a travel direction of the vehicle based on a travel history based on the current position, and a first channel assigned to the uplink radio or the downlink radio corresponding to the identified travel direction When the wireless frame is transmitted by the in-vehicle wireless device and the wireless frame cannot be transmitted even if transmission using the first channel is performed a plurality of times, the direction corresponding to the direction opposite to the specified traveling direction is used. 4. The position according to claim 1, wherein the radio frame is transmitted by the in-vehicle radio using a second channel assigned to the downlink radio or the uplink radio. 5. Detection system. A position detection method for detecting the position of a vehicle traveling on a travel route,
In the vehicle, the GPS receiver receives the current position based on the GPS signal and outputs the current position,
In the route data storage means, the coordinates of a plurality of section blocks set along the traveling route are stored as route data,
Identify the section block where the vehicle is located based on the current position and the route data,
Vehicle information for identifying the vehicle is stored in a vehicle information storage means;
Generating a radio frame including the identified section block and the vehicle information;
The generated wireless frame is transmitted by a vehicle-mounted wireless device using a specific low power wireless band,
A position detection method comprising: receiving a radio frame from the vehicle-mounted radio by a plurality of radios arranged on the travel route.

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