JP2010216955A - Vehicle position presentation method and car navigation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To specify the current position of a vehicle, even at a location having no view over satellites and to improve accuracy in specifying the current position of the vehicle. <P>SOLUTION: Tags 200 are installed in manholes 300 provided at various locations. A reader 500 of a traveling vehicle 400 reads tag reception information (ID) from the tags 200 installed in the manholes 300. A position-specifying section 603 collates read tag reception information (ID) with registration tag information (ID) of a registration tag information storage section 602 and specifies the installation locations (the latitude and longitude) of corresponding tags 200. A map information function section 605 plots the installation locations (the latitude and longitude) of tags supplied from the position specifying section 603 as correction information with a current position (the latitude and longitude) supplied from a GPS function section 604 onto map information and displays them by a display function section 606. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle position presentation method for presenting a position of a vehicle such as an automobile on a map, and a car navigation apparatus.

  A GPS (Global Positioning System) that identifies the position of a vehicle with a car navigation system (hereinafter referred to as a car navigation system) is a system that measures the distance from each of a plurality of GPS satellites and identifies the position of the vehicle. is there. As a conventional technique for improving the identification accuracy, there is a satellite positioning signal receiving device (a device that receives a GPS satellite positioning signal and a Galileo satellite positioning signal of the same type together, hereinafter referred to as a “Galieo combined receiving device”). It is known (see, for example, Patent Document 1).

  FIG. 13 is a block diagram showing a configuration of a conventional Galileo combination receiving apparatus. In the figure, the Galileo combined receiving apparatus includes an antenna 11, an amplifier unit 21, a reference crystal oscillator 51, a digital processing unit 81, and an operation receiving unit 91, mixer units 31 and 32, IF amplifier units 61 and 62, and an IF filter unit. 71 and 72 and local transmitters 41 and 42 have two systems. In the Galileo combined use receiving apparatus, the GPS satellite positioning signal is received in one of the two systems, and the Galileo satellite positioning signal is received on the other side. Only one component is commonly used for positioning signal reception by both GPS and Galileo. Thus, the accuracy of the specific position is improved by using the positioning signal of the GPS satellite and the positioning signal of the Galileo satellite.

  As another conventional technique, a technique using DGPS (differential GPS) that improves an error of a position specified by GPS (improves accuracy) is known (for example, Non-Patent Document 1). FIG. 14 is a block diagram showing a system configuration using DGPS according to the prior art. In the figure, in the system, the position information (latitude and longitude) measured by the GPS receivers 102 and 103 at the DGPS correction station 100 and the lighthouse beacon 101 (both are fixed stations) are converted into accurate position information (latitude and latitude). The correction data (FM correction data, beacon correction data) that is the difference compared to (latitude) is transmitted to the GPS receiver 104 on the vehicle side. FM waves are used to transmit the correction data to the user. The GPS receiver 104 on the vehicle side corrects position information (latitude and longitude) measured by itself using the received correction data. In addition, in the map display such as the car navigation system 105, the accuracy of specifying its own position is improved.

Japanese Patent Laid-Open No. 2005-207888

"Location information business in the IMT-2000 era," INTERNET magazine, pp. 234-pp. 248, 2000/6.

  By the way, as an environment where the GPS used for specifying the position of the car navigation system does not function effectively, there are an urban area where there are many high-rise buildings where satellites cannot be looked over, a lower road of an elevated road, and a tunnel. For example, in a vehicle traveling in a valley of a high-rise building, the range over which the sky can be seen is only 20 ° to 30 °, and the number of all GPS satellites orbiting the earth is 24. ~ Only 2 GPS satellites can be seen. In the GPS receiver, at least four satellites (this is a case of a three-dimensional space, and even when a place is specified on a two-dimensional plane) are required to specify a position. There is a problem that positioning using can not be performed.

  In addition, it is impossible to specify the location even if the Galileo satellite is used. Further, even if radio waves are received from a fixed reference station and a lighthouse beacon that improve positioning accuracy by GPS, it is impossible to specify the position itself. There is a problem that it does not function effectively.

  In addition, in a vehicle traveling under an overhead, it is difficult to receive information by radio waves from GPS satellites (or Galileo satellites, fixed reference stations, lighthouse beacons). Therefore, there has been a problem that the position of the vehicle cannot be specified or the accuracy of the specified position is insufficient.

  Further, even in a vehicle traveling in a tunnel, the vehicle in the tunnel is difficult to receive radio waves from GPS satellites and Galileo satellites as well as fixed reference stations and lighthouse beacons. In this case as well, there is naturally a problem that the position of the vehicle cannot be specified from these pieces of information.

  In car navigation systems, it is convenient to be able to identify the position of the vehicle so that it can be distinguished from the top and bottom of the elevated road, recognize straight and right turn lanes before the intersection, and select the lane at the junction of the expressway. However, as described on page 240 of Non-Patent Document 1, “Currently, in private use, the positioning accuracy always includes an error of about 100 m”, “In Japan, the error of DGPS is Positioning accuracy (several numbers) to achieve the above-mentioned goal, as a new GPS system of the type of correction improves the accuracy of position measurement by about 10 times compared to GPS by direct reception from conventional satellites. It is still insufficient to obtain m).

  The present invention has been made in view of such circumstances, and the object of the present invention is to specify the position of the vehicle even in a place where the satellite cannot be overlooked, and to improve the accuracy of specifying the position of the vehicle. An object of the present invention is to provide a vehicle position presentation method and a car navigation device that can be improved.

  In order to solve the above-described problem, the present invention provides a vehicle position presentation method for presenting the position of a vehicle, which is mounted on the vehicle from a wireless tag installed in a communication facility laid near the vehicle. The identification information of the wireless tag is read by the reading device, and the identification information of the wireless tag and the installation location are associated with the identification information of the read wireless tag from the registered tag information storage unit stored in advance. The vehicle location presentation method includes the steps of: reading out the installed location and specifying the location of the wireless tag; and presenting the specified location of the wireless tag.

  The present invention includes the step of acquiring position information by the GPS function unit mounted on the vehicle in the above invention, and in the step of presenting the installation location of the specified wireless tag, the installation of the specified wireless tag The location is presented on the map information, and the location information acquired by the GPS function unit is presented on the map information.

  According to the present invention, in the above invention, the step of acquiring position information by the GPS function unit at a place where the identification information of the wireless tag is read by the reader, the position information acquired by the GPS function unit, Based on the map information corresponding to the position information, the step of identifying the installation location of the wireless tag, the identification information of the wireless tag and the installation location of the identified wireless tag in association with each other, the registered tag information storage unit And a step of registering with.

  In the present invention according to the present invention, the communication facility is a manhole or a utility pole laid on a road.

  According to the present invention, in the above invention, when the identification information of the wireless tag is read by the reading device mounted on the vehicle, the reading sensitivity of the reading device is increased in order to read the identification information of the wireless tag existing in the vicinity. The method further includes a step of adjusting.

  In order to solve the above-described problem, the present invention provides a car navigation device for presenting a position of a vehicle, and reads identification information of a wireless tag installed in a communication facility laid near the vehicle. The RFID tag identification information read by the reading means from the reading means, the registered tag information storage means for storing the RFID tag identification information and the RFID tag installation location in advance in association with each other, and the registered tag information storage means It comprises: a position specifying unit that reads an associated installation location to identify the installation location of the wireless tag; and a presentation unit that presents the installation location of the wireless tag specified by the position specifying unit. Car navigation device.

  The present invention further includes a GPS function unit that is mounted on the vehicle and acquires position information, and the presenting unit is configured to provide the identified wireless tag when presenting the identified wireless tag installation location. Is provided on the map information, and the position information acquired by the GPS function means is presented on the map information.

  According to the present invention, in the above invention, the GPS function unit acquires position information at a location where the identification information of the wireless tag is read by the reading unit, and the position specifying unit is acquired by the GPS function unit. Based on the position information and the map information corresponding to the position information, the installation location of the wireless tag read by the reading means is specified, and the identification information of the wireless tag and the position specified by the position specifying means are specified. The wireless tag is stored in the registered tag information storage means in association with the installation location of the wireless tag.

  In the present invention according to the present invention, the communication facility is a manhole or a utility pole laid on a road.

  The present invention is characterized in that, in the above invention, when the reading means reads the identification information of the wireless tag, the reading means adjusts its reception sensitivity and reads the identification information of the wireless tag existing closest.

  According to the present invention, a location where the satellite cannot be overlooked by specifying the installation location of the wireless tag based on the identification information read from the wireless tag installed in the communication facility installed in the vicinity of the vehicle, In addition, the current position of the vehicle can be specified, and the accuracy of specifying the current position of the vehicle can be improved.

1 is a block diagram showing a configuration of a vehicle position specifying system according to a first embodiment of the present invention. It is a perspective view which shows the structure of the tag by this 1st Embodiment. In this 1st Embodiment, it is a figure explaining the relationship between the vehicle which drive | works and the manhole in a road. It is a conceptual diagram which shows an example of the tag registration tag information by this 1st Embodiment. FIG. 6 is a conceptual diagram showing a display example of map information on the car navigation system 600 in the first embodiment. In this 1st Embodiment, it is a conceptual diagram which shows a mode that a highly accurate present position is acquired in various situations where a vehicle drive | works. In this 1st Embodiment, it is a conceptual diagram which shows a mode that a highly accurate present position is acquired in various situations where a vehicle drive | works. In this 1st Embodiment, it is a conceptual diagram which shows a mode that a highly accurate present position is acquired in various situations where a vehicle drive | works. In this 1st Embodiment, it is a conceptual diagram which shows the utilization relationship of the tag of a manhole and a car navigation system. It is a block diagram which shows the structure of the vehicle location specification system by 2nd Embodiment of this invention. In this 2nd Embodiment, it is a conceptual diagram which shows the range which can receive the electromagnetic wave from the tag installed in the utility pole. It is a block diagram for demonstrating the registration method of the asset information of a communication installation (tag) by this 3rd Embodiment. It is a block diagram which shows the structure of the Galileo combined use receiver by a prior art. It is a block diagram which shows the system configuration | structure using DGPS by a prior art.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

A. First Embodiment FIG. 1 is a block diagram showing a configuration of a vehicle position specifying system according to a first embodiment of the present invention. In the figure, a wireless tag (IC tag, electronic tag, RF tag, RFID: also referred to as “Redio Frequency Identification”, hereinafter referred to as a tag) 200 is installed in a manhole 300 provided at various places, and a vehicle 400 traveling on a roadway Tag receiving information (ID) for identifying the tag 200 is transmitted to a reading device (also referred to as a reading device, an interrogator, and a tag receiver, hereinafter referred to as a reader) 500 mounted on the device. The reader 500 reads tag reception information (ID) from the tag 200 installed in the manhole 300 and supplies it to the car navigation system 600.

  The car navigation system 600 is mounted on the vehicle 400, and in addition to the existing GPS function unit 604, the map information function unit 605, the display function unit 606, etc., the tag reception information capturing unit 601, the registered tag information storage unit 602, the position specification Part 603 is provided. The tag reception information capturing unit 601 functions as an interface for capturing tag reception information (ID) from the reader 500, and supplies the captured tag reception information (ID) to the position specifying unit 603.

  The registered tag information storage unit 602 stores registered tag information (ID, installation location: longitude, latitude) for a plurality of tags 200 (one in the figure) installed in manholes 300 provided at various locations on the roadway. Pre-held. The data structure of the registration tag information will be described later. The registered tag information is newly registered when the tag 200 is installed, or is appropriately corrected and updated. This will be described in detail in a third embodiment to be described later. The position specifying unit 603 collates the tag reception information (ID) supplied from the tag reception information capturing unit 601 with the registered tag information (ID) stored in the registered tag information storage unit 602, and corresponds to the corresponding tag 200. Is specified and supplied to the map information function unit 605.

  The GPS function unit 604 captures radio waves from four or more GPS satellites, uses high-accuracy transmission time information included in the radio waves, calculates a distance from the time required to reach, and is obtained by calculation. The current position (longitude, latitude) is specified from the distance from four or more satellites, and is supplied to the map information function unit 605. The map information function unit 605 uses the tag installation location (latitude, longitude) supplied from the position specifying unit 603 as correction information, along with the current position (longitude, latitude) supplied from the GPS function unit 604, on the map information. Plot. The display function unit 606 displays map information on which the tag installation location (latitude and longitude) and the current position (longitude and latitude) supplied from the GPS function unit 604 are plotted, which are supplied from the map information function unit 605. .

  FIG. 2 is a perspective view showing the configuration of the tag according to the first embodiment. In the figure, a tag 200 is an active wireless tag equipped with a battery, and includes an antenna (radiation function) 201, a wireless circuit (transmission signal generation function) 202, a pick microcomputer (transmission trigger generation function) 203, a coin battery (power source). Supply function) 204. The antenna 201 transmits a signal using radio waves. The radio circuit 202 generates a signal to be transmitted. The pick microcomputer 203 gives a command to generate and transmit a signal to be transmitted. It also determines the timing of the command. Further, the tag ID (identifier) included in the signal to be transmitted is written, and the ID is sent to the radio circuit 202 to generate a signal. The coin battery 204 supplies power for operating the tag 200 to the wireless circuit 202 and the pick microcomputer 203.

  FIG. 2 shows a battery holder 205 and a printed circuit board 206 as parts for mounting the device configuration of the tag 200. The battery holder 205 stores the coin battery 204. On the printed board 206, a wireless circuit 202 other than the antenna 201 described above, a pick microcomputer 203, and a battery holder 205 are mounted.

  Note that FIG. 2 shows a configuration of an active wireless tag, but even if a passive wireless tag without a battery is used, information on the tag 200 can be read from a reader 500 mounted on a traveling vehicle. Any form may be used.

  In the configuration described above, while the vehicle 400 is traveling on the roadway, the reader 500 mounted on the vehicle 400 reads the tag reception information (ID) from the tag 200 installed in the manhole 300 and the position specifying unit 603. Compares the tag reception information (ID) with the registered tag information (ID), and specifies the installation location (longitude, latitude) of the corresponding tag. The map information function unit 605 displays the specified installation location (longitude, latitude) and the current position obtained from the GPS function unit 604 of the car navigation system on map information, and the display function unit 606 displays the map information function unit 605. Along with the map information from, presents the current position with high accuracy to the user.

  Here, FIG. 3 is a diagram for explaining the relationship between the traveling vehicle and the manhole on the road in the first embodiment. In the figure, a vehicle 400 travels on one lane of a roadway with the arrow direction as the traveling direction. Manholes 300-1 to 300-3 exist on the roadway and the sidewalk, and tags 200-1 to 200-3 are installed in each of these manholes 300-1 to 300-3.

  The vehicle 400 is drawn in the vicinity of the manhole 300-2 that can receive radio waves from the tag 200-2 installed in a nearby manhole (in FIG. 3, the manhole 300-2 to be measured in the opposite lane). The broken circle is traveling in a range in which radio waves can be received, radius: about 5 to 7 m). At this time, the reader 500 mounted on the vehicle 400 receives information on the tag 200-2 installed in the manhole 300-2 to be measured in the opposite lane.

  In addition, although the radio wave of the tag 200-1 installed in the manhole 300-1 of the traveling lane shown in FIG. 3 can be naturally received by the traveling vehicle 400, as shown in the figure, manholes other than the traveling lane (opposite lanes and The radio waves of the tags 200-1 and 200-3 can be received from the manholes 300-1 and 300-3 on the sidewalk (within a radius of about 5 to 7 m). However, in the first embodiment, in order to improve the positional accuracy, the radio wave of the tag 200-1 in the manhole 300-1 only in the traveling lane is captured by setting the reception sensitivity of the reader 500 low. It may be. This can be achieved by setting a small circle between two broken circles drawn around the manholes 300-1 to 300-3 shown in FIG.

  Next, FIG. 4 is a conceptual diagram illustrating an example of tag registration tag information according to the first embodiment. In the figure, as shown in FIG. 4, the registered tag information is a set of ID (tag ID: IDentifier, identifier) and installation location (longitude, latitude). The ID is data in the form of (zzzzz ... zzz), and the installation location is data in the form of longitude and latitude (xxxx, xxx, yyyy ... yyy), for example. Here, x, y, and z are numerical data. These sets are discrete information that matches the number of registered manholes. For example, assuming that there are hundreds of thousands of registered tags in Tokyo, that same hundreds of thousands of manholes exist. However, if a plurality of tags are installed in the manhole, the number is not necessarily the same, but the number of data with the ID and the installation location as one set is a registered tag, and the number of data exceeds the number of manholes.

  FIG. 5 is a conceptual diagram showing a display example of map information on the car navigation system 600 in the first embodiment. In the figure, in block B1, the vehicle 400 is traveling on the road, and the tag reception information (ID) of the tag (not shown) installed in the manhole 300-3 is received by the reader 500 mounted on the vehicle 400. The situation at the time is shown.

  Further, in the range of the example shown in the block B1 in the figure, there are manholes 300-1, 300-2, 300-3, 300-4, and 300-5 on the road, and the vehicle 400 is the manhole 300. -3 represents the time when the vehicle travels over. Accordingly, a reader (not shown) mounted on the vehicle 400 receives tag reception information (ID) of a tag (not shown) installed in the manhole 300-3.

  In the car navigation system 600 of the vehicle 400, the registered tag information storage unit 602 stores the tag ID and the tag installation location (longitude, latitude) in association with each other. In the illustrated example, the installation locations of the tags installed in the manholes 300-1, 300-2, 300-3, 300-4, 300-5,..., 300-n are stored in order from the top. The car navigation system 600 registers in advance as shown in the hatched portion of the registered tag information shown in FIG. 5 by referring to the registered tag information shown in the figure based on the received tag reception information (ID) of the tag. The installation location of the target tag (or manhole, in this case, manhole 300-3) can be specified.

  In particular, for example, in order to display the installation location on the car navigation system based on the tag reception information (ID) from among the registered tag information of hundreds of thousands of manholes existing in Tokyo, the tag installation location is specified at high speed. It may be necessary. For this reason, the registered tag information of the manholes 300-1, 300-2, 300-3, 300-4, and 300-5 existing in the display range of the car navigation (the range of the block B1 shown in FIG. 5) is narrowed down in advance as a reference target. Thus, it is conceivable to specify the installation location based on the tag reception information (ID) from the narrowed registered tag information of the manhole.

  A block B2 shown in FIG. 5 indicates map information displayed on the display function unit 606 of the car navigation system 600. In block B2, the cross M1 is the current position of the vehicle 400 acquired by the GPS function unit 604. Since the current position acquired by the GPS function unit 604 has a large positional accuracy error (as much as several tens of meters) as it is, it is only known that the vehicle 400 is within a wide range indicated by the broken line circle C1.

  Here, since the installation location of the tag (or manhole) is specified based on the tag reception information (ID) from the tag installed in the manhole 300-3, the installation location is displayed on the map information. This is indicated by a cross M2. Note that since the position accuracy of the tag installation location is about several meters, the rectangle M3 including the range (in comparison with the broken line circle C1 that is the current position acquired by the previous GPS function unit 604) (The range is narrow). Thus, the current position of the vehicle 400 can be shown more accurately on the map.

  Here, for example, the tag installation location is displayed on the car navigation system as the current location of the traveling vehicle based on the tag reception information (ID) from among the registered tag information of hundreds of thousands of manholes existing in Tokyo. Therefore, it may be necessary to specify the tag installation location at high speed. For this reason, there is only one manhole 300-3 in the display range of the position acquired by the GPS function (the range of the broken circle C1 shown in FIG. 5). In some cases, the registered tag information is narrowed down in advance as a reference target. It is conceivable to specify the installation location based on the tag reception information (ID) from the registered tag information of the manhole thus narrowed down.

  Next, FIGS. 6, 7, and 8 are conceptual diagrams illustrating how the current position is acquired with high accuracy in various situations in which the vehicle travels in the first embodiment.

  First, FIGS. 6 (a) and 6 (b) are conceptual diagrams showing how to identify which road is running above and below the elevated road, and traveling lanes on a road having a plurality of lanes. It is a conceptual diagram which shows a mode that it identifies. In urban areas, as shown in Fig. 6 (a), many roads are elevated, and there are roads on the upper side of the elevated (elevated road) or roads on the lower side of the elevated (the elevated road exists above) To determine which road each of the vehicles 400-1 and 400-2 traveling on a general road) is traveling only by GPS position information having a large positional accuracy error (about several tens of meters). Is difficult. In particular, it is difficult to receive radio waves from GPS satellites on the roads under the overpass (general roads with elevated roads above), and it is possible that the current position cannot be identified even with DGPS with improved error even if it is received together with Galileo. is there.

  Therefore, the tags 200-1 and 200-2 are installed on the manholes 300-1 and 300-2 (in the upper elevated road and the lower general road in that order) on the respective roads. Tag reception information (ID) from the tags 200-1 and 200-2 installed in the manholes 300-1 and 300-2 by readers (not shown) mounted on the traveling vehicles 400-1 and 400-2. Can be used to identify the position even if you are traveling on the lower road of the elevated road (the general road that is the lower side of the elevated road). It is possible to identify with high accuracy whether the vehicle is traveling on the lower general road).

  Also, as shown in FIG. 6B, the vehicle lane of a vehicle traveling on a road having a plurality of lanes can be identified only by GPS position information having a large positional accuracy error (about several tens of meters). It is difficult to identify. That is, the road having a plurality of lanes is divided into a straight lane and a right turn lane before the intersection. It is difficult to determine whether the traveling vehicle is in a straight lane or a right turn lane before the intersection by using only GPS position information.

  On the road shown in FIG. 6B, a manhole 300 is located near the center line on the right turn lane before the intersection. Therefore, when the tag 200 is installed in the manhole 300, only the vehicle traveling on the right turn lane can receive the tag reception information (ID) of the tag 200 at a signal intensity level higher than a certain level. That is, if the radio waves of the tag 200 in the manhole 300 can be clearly received, it can be reliably determined that the vehicle 400 is approaching the intersection while traveling on the right turn lane. In FIG. 6 (b), the driving lane is judged just before the intersection where the straight lane and the right turn lane are, but it can be applied to the selection of the lane before the junction (branch) on the highway as well. Also, it can be used to determine the lane of whether the vehicle is traveling on the exit lane from the highway to the general road or on the travel lane on the highway as it is before the interchange.

  Next, FIGS. 7 (a) and 7 (b) are a conceptual diagram showing how to identify the exact current position of a vehicle when a vehicle traveling on the road enters the tunnel, and in the junction of the expressway, respectively. It is a conceptual diagram which shows a mode that a driving lane is identified. As shown in FIG. 7A, a vehicle 400 traveling on a road may enter a tunnel 700. Conventionally, in the car navigation system, the current position Lx of the vehicle 400 traveling in the tunnel 700 is determined by applying to the map information from the entrance Lstart of the tunnel 700 according to the travel distance. Thereafter, when the vehicle passes the exit Lend of the tunnel 700, the current position is determined by GPS. That is, in the tunnel 700, the current position cannot be specified by GPS in principle. Therefore, it is very effective to specify the current position of the vehicle 400 traveling in the tunnel 700 using the radio waves of the tag 200 installed in the manhole 300 as described above.

  Therefore, in the first embodiment, a tag (not shown, corresponding to the tag 200 in FIG. 1) is installed in the manhole 300 in the tunnel 700, and tag reception information (ID) from the tag 200 is received. When the current position of the vehicle 400 is corrected with the installation location (longitude, latitude) of the tag 200 (within the tunnel 700, the installation location of the tag 200 is the current location), the tunnel is between the tunnel entrance Lstart and the exit Lend. The accuracy of the current position Lx of the vehicle traveling in 700 can be reliably improved.

  Further, as shown in FIG. 7B, it is difficult to specify the lane in which the vehicle travels using only GPS position information even at a junction where a highway having a plurality of lanes is three-dimensionally crossed. FIG. 7B shows a junction where a highway connecting three directions indicated by A, B, and C is three-dimensionally crossed. In each of the directions A, B, and C, there are two lanes ab, ac, and bc in the upward and downward directions, respectively. The arrow on the travel lane indicates the travel direction of the vehicle.

  That is, when entering the junction from the direction A, it is necessary to select the travel lane b when going to the direction B, and to select the travel lane c when going to the direction C. Further, when entering the junction from the direction B, it is necessary to select the travel lane a when going to the direction A, and to select the travel lane c when going to the direction C. Similarly, when entering the junction from the direction C, it is necessary to select the travel lane a when going to the direction A, and to select the travel lane b when going to the direction B. In the illustrated example, the case where the vehicle 400 enters the junction from the direction C is shown.

  The vehicle 400 traveling from the direction C to the junction needs to select one of the traveling lanes a and b depending on the target direction A or direction B. The driver determines the driving lane by looking at the sign in front of the junction and the car navigation display. In the first embodiment, the current position of the traveling vehicle 400 is specified by receiving tag reception information (ID) from a tag (not shown, corresponding to the tag 200 in FIG. 1) installed in the manhole 300. It is possible to identify which of the traveling lanes a and b the traveling vehicle is traveling.

  Next, FIGS. 8A and 8B are conceptual diagrams for explaining a case where the current position of the vehicle is specified in a low-rise residential area and an urban area with many high-rise buildings in the first embodiment. . In the case where the accuracy of the current position is improved by the tag reception information (ID) from the tag 200 according to the first embodiment, as a situation where the surrounding environment of the traveling vehicle is different, a low-rise residential area and an urban area with many high-rise buildings There is.

  As shown in FIG. 8A, in the low-rise residential area, when the sky is viewed from the traveling vehicle 400, the sky is open in a relatively wide range of 90 ° to 140 °. For this reason, out of all 24 GPS satellites orbiting the earth, radio waves from about 6 to 9 GPS satellites can always be directly received by the vehicle 400, and information on four or more GPS satellites can be received. If there is, the current position can be specified.

  However, the accuracy of specifying the location by GPS is low, and there is an error of about 100 m in some cases. It is difficult to significantly improve this error even when the Galileo satellite is used in combination. DGPS using the above-mentioned fixed reference station (lighthouse beacon) can identify the current position with an error of about 10 m and can improve accuracy by 10 times or more, but for low-rise residential areas with low population density, etc. Therefore, the construction of a fixed reference station (lighthouse beacon) is not cost effective and cannot be expected.

  Therefore, as described above, in the first embodiment, the tag 200 is installed in the manhole 300 as the existing communication equipment, and the tag reception information (ID) from the tag 200 is installed in the traveling vehicle 400. By receiving the data from the vehicle 500 and specifying the current position of the vehicle with the car navigation system 600, the vehicle can be realized with higher accuracy (within several meters) than the GPS alone and at a lower cost than the DGPS.

  In the urban area where there are many high-rise buildings shown in FIG. 8B, the sky can be seen only in a relatively narrow range of 20 ° to 30 ° with respect to the low-rise residential area. Therefore, it is possible to receive radio waves directly from only one or two GPS satellites out of all 24 satellites orbiting the earth, and the current position cannot be specified (in the case of a three-dimensional space, the current position is specified). The number of GPS satellites required for this is four or more, and information on three or more GPS satellites is required to specify the current position on a two-dimensional plane).

  Therefore, as described above, in the first embodiment, the tag 200 is installed in the manhole 300 as an existing communication facility. In urban areas, most communication facilities are buried in the ground, and the manhole 300 exists on many roads for maintenance of the communication facilities. Therefore, even in an urban area where there are many high-rise buildings, by receiving the tag reception information (ID) from the tag 200 installed in the manhole 300 by the reader 500 mounted on the traveling vehicle 400, The current position can be specified with high accuracy within several meters.

  According to the first embodiment described above, when the tag reception information (ID) from the tag 200 installed in the manhole 300 is used as a marker for indicating the position to improve the accuracy of the current position specified by the car navigation system 600. However, since the position specifying function by the GPS function unit 604 is supplemented to the last, the reading rate of the tag 200 may not be 100%. Incidentally, as the position accuracy obtained using GPS, the car navigation system 600 normally has an error of tens of meters to several tens of meters (in some cases, 100 meters). On the other hand, when tag reception information (ID) from the tag 200 installed in the manhole 300 is used as a marker, it is a few meters (normally 5 to 7 m, 2 to 2 if the reception level of radio waves is limited). Position accuracy of about 3 m) can be realized. Therefore, in GPS, it is possible to receive and sufficiently correct tag reception information (ID) from the tag 200 installed in the manhole 300 with insufficient positional accuracy.

  In the first embodiment, among the functions newly added to the car navigation system 600, the registration tag information in the registration tag information storage unit (ID, location) 602 is the asset registration of the communication facility in the third embodiment to be described later. / The correction method will be described in detail. That is, as shown in FIG. 9, in improving the accuracy of specifying the current position of the vehicle 400 described in the first embodiment, asset information (installation location) of the tag 200 and the manhole 300 described in the third embodiment described later. This is realized by using the registration information created by registration.

B. Second Embodiment Next, a second embodiment of the present invention will be described.
FIG. 10 is a block diagram showing a configuration of a vehicle position specifying system according to the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected and demonstrated to the part corresponding to FIG. In the figure, in the second embodiment, in order to improve the position accuracy when the current position is specified in the vehicle 400, the tags 200-1, 200 are installed on the power poles 800-1, 800-2 laid along the road. -2 is received, tag reception information (ID) is received from the tags 200-1 and 200-2 by the reader 500 mounted on the vehicle 400, and the installation location of the tags 200-1 and 200-2 is received by the car navigation system 600. The current position of the vehicle 400 is specified from (longitude, latitude).

  As shown in FIG. 10, the tags 200-1 and 200-2 are installed on the utility poles 800-1 and 800-2. Or it may replace with a utility pole and may be closure 900-1, 900-2 which connects and branches a communication line. A vehicle 500 traveling on the road is equipped with a reader 500 that receives tag reception information (ID) from the tags 200-1 and 200-2, a car navigation system 600 that specifies the current position of the vehicle and provides map information. The utility poles 800-1 and 800-2 are erected on the end of the sidewalk or along the shoulder along the road, and the tags 200-1 and 200-2 are installed at a high place of the utility poles 800-1 and 800-2. Keep it. When the vehicle 400 approaches the utility poles 800-1 and 800-2, the reader 500 mounted on the vehicle 400 traveling on the road receives tag reception information (ID) from the tags 200-1 and 200-2. .

  Further, there are one communication line closure 900-1 and 900-2 for every two utility poles, and the same applies even when the tags 200-1 and 200-2 are installed in the closure 900-1 and 900-2. The reader 500 mounted on the traveling vehicle 400 receives the tag reception information (ID) from the tags 200-1 and 200-2 when the vehicle 400 approaches.

  The installation locations of the utility poles 800-1 and 800-2 or the closures 900-1 and 900-2 on which the tags 200-1 and 200-2 are installed are registered in advance, and the tags 200-1 and 200-2 The registration tag information storage unit 602 of the car navigation system 600 mounted on the vehicle 400 stores a large amount of registration tag information. Based on the IDs of the tags 200-1 and 200-2 received by the reader 500 mounted on the vehicle 400, the car navigation system 600 determines the installation location (longitude and latitude) where the tags 200-1 and 200-2 are installed. Since it can be recognized, the current position of the vehicle can be specified with high accuracy.

  FIG. 11 is a conceptual diagram showing a range in which radio waves can be received from a tag installed on a utility pole in the second embodiment. Consider the range in which radio waves can be received from the tag 200 installed on the utility pole. It is assumed that the height of the utility pole 800 or the closure 900 shown in FIG. 11 is 5 m. And the receiving range of the electromagnetic wave from this electric pole 800 or the tag 200 installed in the closure 900 shall be about 10 m. When such a condition is assumed, the reception range on the ground is 8.6 m. Since the size of the vehicle 400 is 4-5 m, the range for two vehicles can be covered. The specific accuracy of the current position is very high compared to the GPS error of 100 m in some cases, and is 10 times that of GPS, and even better than DGPS having an error of about 10 m. .

  In addition, when it is necessary to obtain the position with higher accuracy, such as determination of a lane to travel, it is conceivable to limit the reception level of the reader 500 that receives the radio waves of the tag 200. For example, it is possible to provide a threshold for the intensity of the reception level of the radio wave from the tag 200 and to set the accuracy of specifying the position to 4 m or less (shown inside two broken circles surrounding the tag 200 in FIG. 11). In addition, the radio wave reception range of the tag 200 installed in the utility pole 800 or the closure 900 is assumed to be about 10 m so far. For example, if the reception range is 20 m, the strength of the reception level at the reader 500 is the same as before. The accuracy of specifying the position can be adjusted.

  The power pole 800 and the communication line closure 900 are subjected to maintenance confirmation inspection every several years, and work may be performed each time depending on the construction of the communication line. It is very effective to install the tag 200 during such maintenance inspections and construction work so that it can be used to improve the accuracy of specifying the current position of the vehicle 400 thereafter. The number of utility poles 800 and communication line closures 900 for which the tag 200 in the second embodiment is to be installed is several tens of times the number of manholes in the first embodiment. And many. In particular, the utility pole 800 and the communication line closure 900 are often used in low-rise residential areas. In such low-rise residential areas, the current position can be specified by GPS, but it is not sufficient for identifying the driving lane. Therefore, it is preferable to improve the accuracy of specifying the current position of the vehicle according to the second embodiment.

C. Third Embodiment Next, a third embodiment of the present invention will be described.
As described above, in the first and second embodiments, the tag 200 is installed in the manhole 300, the utility pole 800, and the closure 900, and the tag reception information (ID) from the tag 200 is read by the reader 500 of the traveling vehicle 400. ) And the car navigation system 600 displays and presents the installation location of the tag 200 and the current position by GPS on map information. In such a configuration, when a tag 200 is newly installed in the manhole 300, the utility pole 800, and the closure 900, the installation location of the tag 200 is set as a registered tag information storage unit of the car navigation system 600 mounted on the vehicle 400. It is necessary to register in 602 as registration tag information (ID, installation location: longitude, latitude). It is also necessary to update (correct) the registered tag information (ID, installation location: longitude, latitude) of the tag 200 that has already been installed.

  Hereinafter, when a tag 200 is newly installed in the manhole 300, a method for registering the registered tag information (ID, installation location: longitude, latitude) of the tag 200 in the registered tag information storage unit 602 of the car navigation system 600 will be described. To do.

  FIG. 12 is a block diagram for explaining a method for registering asset information of a communication facility (tag) according to the third embodiment. It should be noted that portions corresponding to those in FIG. In the figure, the vehicle 400 pauses on the manhole 300 where the tag 200 to be registered (or updated) is installed (it is acceptable if it can communicate with the tag 200). In this state, the reader 500 mounted on the vehicle 400 reads tag reception information (ID) from the tag 200 installed in the manhole 300 and supplies it to the car navigation system 600. The car navigation system 600 captures tag reception information (ID) and supplies it to the position specifying unit 603.

  The position specifying unit 603 collates the tag reception information (ID) supplied from the tag reception information capturing unit 601 with the registered tag information (ID) stored in the registered tag information storage unit 602, and corresponding tags It is determined whether or not the ID of 200 is stored in the registered tag information storage unit 602. If the ID of the corresponding tag 200 is not stored in the registered tag information storage unit 602, the tag 200 is registered in the registered tag information storage unit 602 because it is a new tag 200. On the other hand, if the ID of the corresponding tag 200 already exists in the registered tag information storage unit 602, the setting location is updated (or corrected), and therefore the ID of the corresponding tag 200 is specified here.

  On the other hand, the GPS function unit 604 measures the distance from each of the plurality of GPS satellites, specifies the current position (longitude, latitude), and supplies the current position to the map information function unit 605. The map information function unit 605 supplies map information (such as a road position) based on the current position supplied from the GPS function unit 604 to the position specifying unit 603. The position specifying unit 603 specifies the installation location (latitude, longitude) of the specified tag 200 according to the current position acquired by the GPS function unit 604 and map information (road position, etc.), and uses the ID of the tag 200 as the ID. Correspondingly, it is registered (or updated or corrected) as registered tag information (installation location) in the registered tag information storage unit 602.

  Through the series of procedures as described above, the registered tag information of the tag 200 installed in the manhole 300, the utility pole 800, or the communication line closure 900 existing on the lane side where the vehicle travels can be easily registered, updated, and corrected. be able to.

  By the way, in the road as shown in FIG. 3, there are manholes 300-2 and 300-3 on the opposite lane and the sidewalk, or on the opposite lane side in the road shown in FIG. Tags 200-2, 200-3 (FIG. 3) installed in these manholes 300-2, 300-3, or tags 200-2 (FIG. 3) installed in a power pole 800-2 or a communication line closure 900-2. The radio wave 10) can be received even in the lane in which the vehicle 400 travels. Thus, although it is different from the lane in which the vehicle 400 travels, the manholes 300-2 and 300-3 in which the tags 200-2 and 200-3 are installed (the opposite lane and the sidewalk as shown in FIG. 3). Or the power pole 800-2 on which the tag 200-2 is installed, or the communication line closure 900-2 (the place corresponding to the exact opposite lane shown in FIG. 10) is within the range where radio waves can be received. If it is in the vicinity, care must be taken when registering the position information.

  That is, the tags 200-2 and 200-3 (FIG. 3) installed in the manholes 300-2 and 300-3, or the tag 200- installed in the utility pole 800-2 or the communication line closure 900-2. For radio waves from 2 (FIG. 10), the reception level at the reader 500 is restricted. Due to the restriction of the reception level, the tags 200-2 and 200-3 installed in the opposite lane in FIG. 3 and the manholes 300-2 and 300-3 on the sidewalk are installed in the manhole 300-1 in the traveling lane. It is made distinguishable from the tag 200-1 (the circle inside the two dashed circles surrounding the tag shown in FIG. 3 is the reception range). Alternatively, the power pole 800-2 in the opposite lane in FIG. 10 or the tag 200-2 installed in the communication line closure 900-2 is replaced with the power pole 800-1 in the travel lane or the communication line closure 900-. 1 is set so that it can be distinguished from the tag 200-1 installed in 1 (the circle inside the two dashed circles surrounding the tag shown in FIG. 11 is the reception range).

  Registration of equipment assets in the opposite lane, manholes 300-2 and 300-3 (Fig. 3) on the sidewalk, or the utility pole 800-2 in the opposite lane, or the communication line closure 900-2 (Fig. 10). At that time, in order to perform accurate data registration / correction, the vehicle 400 is temporarily stopped on the side of the road (the shoulder of the road) and the manholes 300-2 and 300-3 or the utility poles 800-2, In addition, it is necessary to accurately grasp information indicating in which direction the communication line closure 900-2 is displaced from the stopped vehicle 400 by that amount.

  Thus, if the installation location of the tag 200 is accurately registered, it is useful for both the current situation survey and the improvement of the positional accuracy of the vehicle 400 by the car navigation system 600. That is, as shown in FIG. 5, when referring to the registered tag information registered with the installation location of the tag 200 described in the third embodiment, the vehicle as described in the first and second embodiments described above. 400 current positions can be specified with high accuracy.

  According to the first to third embodiments described above, the satellite is identified by identifying the installation location of the wireless tag based on the identification information read from the wireless tag installed in the communication facility laid near the vehicle. It is possible to specify the current position of the vehicle even in a place that cannot be overlooked, and to improve the accuracy of specifying the current position of the vehicle. For example, the GPS of a car navigation system can identify the current position of a vehicle even when driving in an urban area where there are many high-rise buildings that are difficult to measure, in a lower road of an elevated road, or in a tunnel. In addition, it is possible to identify the lane selected by distinguishing the elevated road from the road underneath, recognizing straight ahead and right turn lanes before the intersection, and the junction of the expressway.

200, 200-1 to 200-3 Tag 201 Antenna 202 Radio circuit 203 Pick microcomputer 204 Coin battery 205 Battery holder 206 Printed circuit board 300, 300-1 to 300-n Manhole 400, 400-1, 400-2 Vehicle 500 Reader 600 Car navigation system 601 Tag reception information capturing unit 602 Registered tag information storage unit 603 Position specifying unit 604 GPS function unit 605 Map information function unit 606 Display function unit 700 Tunnel 800, 800-1, 800-2 Telephone pole 900, 900-1, 900- 2 Closure

Claims (10)

A vehicle position presentation method for presenting the position of a vehicle,
Reading identification information of the wireless tag from a wireless tag installed in a communication facility installed in the vicinity of the vehicle by a reader mounted on the vehicle;
The installation location associated with the read identification information of the wireless tag is read out from the registered tag information storage unit in which the identification information of the wireless tag and the installation location are stored in advance, and the installation location of the wireless tag Identifying steps,
Presenting the installation location of the identified wireless tag. A vehicle position presentation method comprising: Obtaining position information by a GPS function unit mounted on the vehicle;
Including
In the step of presenting the specified installation location of the wireless tag, the installation location of the specified wireless tag is presented on map information, and the location information acquired by the GPS function unit is presented on the map information. The vehicle position presentation method according to claim 1, wherein the vehicle position is presented. Obtaining position information by the GPS function unit at a location where the identification information of the wireless tag is read by the reader;
Identifying an installation location of the wireless tag based on position information acquired by the GPS function unit and map information corresponding to the position information;
The vehicle position presentation method according to claim 2, further comprising: associating the identification information of the wireless tag and the installation location of the identified wireless tag in association with each other in the registered tag information storage unit. The communication facility is:
The vehicle position presentation method according to any one of claims 1 to 3, wherein the vehicle position presentation method is a manhole or a utility pole laid on a road.   When the identification information of the wireless tag is read by the reading device mounted on the vehicle, the method further includes the step of adjusting the reception sensitivity of the reading device in order to read the identification information of the wireless tag existing closest. The vehicle position presentation method according to any one of claims 1 to 4. A car navigation device for presenting a position of a vehicle,
Reading means for reading identification information of a wireless tag installed in a communication facility laid near the vehicle;
Registered tag information storage means for preliminarily storing the identification information of the wireless tag and the installation location of the wireless tag in association with each other;
From the registered tag information storage means, a location specifying means for reading the installation location associated with the identification information of the wireless tag read by the reading means, and specifying the installation location of the wireless tag;
A car navigation apparatus comprising: presenting means for presenting an installation location of the wireless tag identified by the position identifying means. Further equipped with GPS function means mounted on the vehicle to obtain position information;
The presenting means is
When presenting the installation location of the specified wireless tag, the installation location of the specified wireless tag is presented on map information, and the location information acquired by the GPS function means is presented on the map information. The car navigation device according to claim 6. The GPS function means is
Obtaining the position information at the place where the identification information of the wireless tag is read by the reading means;
The position specifying means includes
Based on the position information acquired by the GPS function unit and the map information corresponding to the position information, the installation location of the wireless tag read by the reading unit is specified, and the identification information of the wireless tag and the position The car navigation device according to claim 7, wherein the registration tag information storage unit stores the wireless tag installation location specified by the specification unit in association with each other. The communication facility is:
The car navigation device according to any one of claims 6 to 8, wherein the car navigation device is a manhole or a utility pole laid on a road. The reading means includes
10. The car navigation device according to claim 6, wherein when the identification information of the wireless tag is read, the reception sensitivity of the wireless tag is adjusted, and the identification information of the wireless tag existing closest to the wireless tag is read.

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