JP2016008939A - Wireless communication device and wireless positioning system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable positioning without dependence on an individual difference among mobile communication devices.SOLUTION: A reference station 2 receives vehicle-velocity-pulse integrated value information from each on-vehicle device 3 directly by wireless communication and detects a received signal intensity at a time of this reception. A management server 4 stores reference locus information indicating a reference locus on which two or more points of correspondence relations are set between the received signal intensity and a distance (hereinafter referred to as reference moving distance) by which a vehicle travels on a road near the reference station 2. The management server 4 creates a probe locus indicating correspondence relations between a plurality of received signal intensities and a plurality of target vehicle moving distances calculated on the basis of the vehicle-velocity-pulse integrated value information, and compares the reference locus with the probe locus, thereby determining a correspondence relation between a reference moving distance and each target vehicle moving distance. Furthermore, the management server 4 determines a current position of each on-vehicle device 3 on the basis of the correspondence relation between the reference moving distance and the target vehicle moving distance and the current received signal intensity, and the reference station 2 transmits positioning information indicating the current position to each on-vehicle device 3.

Description

  The present invention relates to a wireless communication apparatus and a wireless positioning system that perform positioning by wireless communication.

  Conventionally, a wireless communication device (hereinafter referred to as a mobile communication device) mounted on a mobile body moving on a road near the reference station detects the received signal strength when a wireless beacon periodically transmitted from the reference station is received. Thus, a technique for measuring the current position of the mobile communication device is known (see, for example, Patent Document 1).

JP 2013-257306 A

  However, in the technique described in Patent Document 1, since the mobile communication device receives a wireless beacon, the detected value of the received signal strength when the wireless beacon is received due to the individual difference of the mobile communication device is the mobile communication device. It may be different for each. For this reason, there exists a possibility that the measured value of the present position by a mobile communication apparatus may change according to the individual difference of a mobile communication apparatus.

  The present invention has been made in view of these problems, and an object of the present invention is to provide a technique that enables positioning independent of individual differences of mobile communication devices.

  In order to achieve the above object, a wireless communication apparatus according to claim 1 has a function of receiving data transmitted from a mobile communication apparatus mounted on a mobile body and performing wireless communication by direct wireless communication. The wireless communication apparatus according to claim 1 is an information receiving unit, a first detecting unit, a reference information storing unit, a first creating unit, a first correspondence relationship determining unit, and a first position determining unit. And position transmitting means.

  The information receiving means receives first relative distance related information, which is information related to the relative distance between the mobile communication device and the wireless communication device, directly from the mobile communication device by wireless communication. And a 1st detection means detects the radio | wireless reception condition when an information reception means receives 1st relative distance relevant information. The reference information storage means is correspondence reference information in which two or more correspondence relations between the wireless reception status detected by the first detection means and the position related information that is information related to the position of the mobile communication device are set. Remember.

  Then, the first creation means creates first correspondence information indicating a correspondence relationship between the plurality of wireless reception situations detected by the first detection means and the plurality of first relative distance related information received by the information reception means. . Thereafter, the first correspondence relationship determining means determines the correspondence relationship between the position related information and the first relative distance related information by comparing the correspondence relationship reference information with the first correspondence relationship information. Further, the first position determining means includes the correspondence relation between the position related information and the first relative distance related information determined by the first correspondence relation determining means, and the current wireless reception status detected by the first detecting means. Based on this, a mobile current position that is the current position of the mobile communication device is determined. The position transmitting means transmits positioning information indicating the current position of the moving body determined by the first position determining means to the mobile communication device.

  In the wireless communication device configured as described above, the wireless communication device detects the wireless reception status when data transmitted from the mobile communication device is directly received by wireless communication, so that the current state of the mobile communication device is detected. The position can be determined. Therefore, according to the wireless communication device of the first aspect, it is possible to perform positioning of the mobile body regardless of individual differences in the detection performance of the wireless reception status in the mobile communication device.

  A wireless positioning system according to claim 7, which is made to achieve the above object, includes a first wireless communication device that is the wireless communication device according to claim 1, and a mobile communication device according to claim 1. A second wireless communication apparatus.

  The wireless positioning system configured as described above includes the wireless communication device according to claim 1, and can obtain the same effects as the wireless communication device according to claim 1.

It is a figure showing composition of radio positioning system 1 of a 1st embodiment. 2 is a block diagram showing a configuration of a reference station 2. FIG. 3 is a block diagram illustrating a configuration of an in-vehicle device 3. FIG. 3 is a block diagram showing a configuration of a management server 4. FIG. It is a flowchart which shows the vehicle side transmission / reception process of 1st Embodiment. It is a flowchart which shows the reference | standard station side transmission / reception process of 1st Embodiment. It is a flowchart which shows the server side transmission / reception process of 1st Embodiment. It is a figure which shows a reference | standard locus | trajectory. It is a figure explaining the position determination method using a reference locus and a probe locus. It is a figure which shows the structure of the wireless positioning system 101 of 2nd Embodiment. 2 is a block diagram showing a configuration of a reference station 102. FIG. It is a flowchart which shows the reference | standard station side transmission / reception process of 2nd Embodiment. It is a block diagram which shows the structure of the vehicle-mounted apparatus 3 of 3rd Embodiment. It is a flowchart which shows the vehicle side transmission / reception process of 3rd Embodiment.

(First embodiment)
A first embodiment of the present invention will be described below with reference to the drawings.
As shown in FIG. 1, a wireless positioning system 1 according to the present embodiment includes a plurality of reference stations 2 (two reference stations 2a and 2b shown in FIG. 1) that are installed in the vicinity of a road and perform direct wireless communication, and an automobile. The vehicle-mounted device 3 that is directly mounted and performs wireless communication (FIG. 1 shows three vehicle-mounted devices 3a, 3b, and 3c) and the management server 4 that manages data for measuring the position of the vehicle-mounted device 3 It is configured.

As illustrated in FIG. 2, the reference station 2 includes a direct wireless communication device 11, a wide area wireless communication device 12, and a control unit 13.
The direct wireless communication device 11 performs direct wireless communication with the in-vehicle device 3. The wide area wireless communication device 12 performs data communication with the management server 4 via the wide area wireless communication network NW. The control unit 13 includes a CPU 21, a ROM 22, and a RAM 23, and directly controls the wireless communication device 11 and the wide area wireless communication device 12 by the CPU 21 executing a process based on a program stored in the ROM 22.

As shown in FIG. 3, the in-vehicle device 3 includes a vehicle speed sensor 31, a position detector 32, a direct wireless communication device 33, and a control unit 34.
The vehicle speed sensor 31 outputs a vehicle speed pulse that changes from a low level to a high level at every predetermined angle according to the rotation of the axle. Based on the vehicle speed pulse, the control unit 34 calculates the speed of the vehicle (hereinafter referred to as the host vehicle) on which the in-vehicle device 3 is mounted.

  The position detector 32 is composed of a plurality of sensors such as a GPS receiver that receives satellite signals from GPS satellites, a distance sensor that detects the travel distance of the host vehicle from the rotation of wheels, and an orientation sensor. Based on the obtained signal, the position and traveling direction of the host vehicle are detected. Then, the detection result of the position detector 32 is input to the control unit 34.

  Note that the GPS receiver included in the position detector 32 uses an RTK-GPS (Real Time Kinematics Global Positioning System) system. In the RTK-GPS method, the position can be detected with an accuracy of several centimeters by correcting the detection result based on the signal received from the GPS satellite using the correction information received from the GPS fixed reference station.

  The position detector 32 calculates the detection accuracy of the position detection result and outputs position accuracy information indicating the position detection accuracy to the control unit 34. Specifically, the position detector 32 is set in advance when the position is detected using the correction information received from the GPS fixed reference station (hereinafter referred to as the RTK-FIX state). RTK-FIX detection accuracy (2 cm in this embodiment) is calculated as detection accuracy. On the other hand, if the position detector 32 is not in the RTK-FIX state, the position detector 32 continues with the duration during which the state is out of the RTK-FIX state, and the detection accuracy of the sensors (distance sensor, azimuth sensor, etc.) Based on the above, the detection error is accumulated as the duration time becomes longer, and this detection error is calculated as the detection accuracy.

The direct wireless communication device 33 performs direct wireless communication with the reference station 2.
The control unit 34 includes a CPU 41, a ROM 42, and a RAM 43, and directly controls the wireless communication device 33 when the CPU 41 executes a process based on a program stored in the ROM 42.

Further, every time a vehicle speed pulse is input from the vehicle speed sensor 31, the control unit 34 performs a process of incrementing (adding 1) a vehicle speed pulse counter provided in advance in the RAM 43.
As shown in FIG. 4, the management server 4 includes a wide area wireless communication device 51, a map data storage device 52, and a control unit 53.

The wide area wireless communication device 51 performs data communication with the reference station 2 via the wide area wireless communication network NW.
The map data storage device 52 stores map data (node data, link data, road data, terrain data, mark data, intersection data, temporary stop point data, facility data, etc.).

  The control unit 53 includes a CPU 61, a ROM 62, and a RAM 63, and controls the wide area wireless communication device 51 when the CPU 61 executes a process based on a program stored in the ROM 62. The RAM 63 of the control unit 53 stores reference trajectory information (described later) regarding each of the plurality of reference stations 2.

  In the wireless positioning system 1 configured as described above, the reference station 2 executes reference station side transmission / reception processing (described later), the in-vehicle device 3 executes vehicle side transmission / reception processing (described later), and the management server 4 performs server side transmission / reception processing (described later). (To be described later).

First, the procedure of the vehicle side transmission / reception process which CPU41 of the vehicle-mounted apparatus 3 performs is demonstrated. This vehicle side transmission / reception process is a process repeatedly executed during the operation of the CPU 41.
When this vehicle side transmission / reception process is executed, as shown in FIG. 5, first, in S10, the CPU 41 determines whether or not a predetermined periodic transmission cycle has elapsed since the previous transmission of the own vehicle information (described later). Determine whether. If the regular transmission cycle has not elapsed since the previous transmission (S10: NO), the process proceeds to S40.

  On the other hand, if the regular transmission cycle has elapsed since the previous transmission (S10: YES), the vehicle information is created in S20. The own vehicle information includes vehicle identification information, vehicle type information, vehicle speed pulse integrated value information, transmission power information, own vehicle position information, and the above position accuracy information.

  The vehicle identification information is information for identifying the host vehicle. The vehicle type information is information indicating the vehicle type of the host vehicle. The vehicle speed pulse integrated value information is information indicating a value of a vehicle speed pulse counter (hereinafter referred to as a vehicle speed pulse integrated value). The transmission power information is information indicating transmission power when the direct wireless communication device 33 of the in-vehicle device 3 transmits the own vehicle information. The own vehicle position information is information indicating a current position (hereinafter, referred to as a GPS position) detected by the position detector 32.

Furthermore, in S30, the own vehicle information created in S20 is directly transmitted to the wireless communication device 33, and the process proceeds to S40.
In S40, it is determined whether positioning information (described later) has been received from the reference station 2. Here, when positioning information is not received (S40: NO), a vehicle side transmission / reception process is once complete | finished. On the other hand, if positioning information is received (S40: YES), it is determined in S50 whether or not the received positioning information is addressed to the host vehicle based on the vehicle identification information included in the received positioning information. .

  If the positioning information is not addressed to the host vehicle (S50: NO), the received positioning information is discarded in S60, and the vehicle side transmission / reception process is temporarily terminated. On the other hand, if the positioning information is addressed to the host vehicle (S50: YES), the received positioning information is stored in the RAM 43 in S70, and the vehicle side transmission / reception process is temporarily terminated.

Next, the reference station side transmission / reception processing procedure executed by the CPU 21 of the reference station 2 will be described. This reference station side transmission / reception process is a process repeatedly executed during the operation of the CPU 21.
When this reference station side transmission / reception process is executed, the CPU 21 first determines whether or not the host vehicle information has been received from the in-vehicle device 3 in S110, as shown in FIG. Here, when own vehicle information is not received (S110: NO), it transfers to S140.

  On the other hand, when the own vehicle information is received (S110: YES), the received signal strength RSSI of the received own vehicle information is detected at S120. Thereafter, in S130, the received signal strength information indicating the received signal strength RSSI detected in S120 is transmitted to the management server 4 together with the own vehicle information received in S110, and the process proceeds to S140.

  In S140, it is determined whether positioning information (described later) has been received from the management server 4. Here, when the positioning information is not received (S140: NO), the reference station side transmission / reception processing is temporarily ended. On the other hand, when the positioning information is received (S140: YES), the positioning information received from the management server 4 is directly transmitted to the wireless communication device 11 in S150, and the reference station side transmission / reception processing is once ended.

Next, a procedure of server side transmission / reception processing executed by the CPU 61 of the management server 4 will be described. This server-side transmission / reception process is a process repeatedly executed during the operation of the CPU 61.
When this server-side transmission / reception process is executed, the CPU 61 first determines whether or not the received signal strength information and the own vehicle information are received from the reference station 2 in S210 as shown in FIG. Here, when the received signal strength information and the own vehicle information are not received (S210: NO), the server-side transmission / reception process is temporarily terminated.

  On the other hand, when received signal strength information and own vehicle information are received (S210: YES), a probe trajectory is created in S220. Specifically, first, regarding the vehicle specified by the vehicle identification information included in the host vehicle information received in S210 (hereinafter referred to as the target vehicle), the target vehicle from the time when the host vehicle information of the target vehicle is first received. The travel distance (hereinafter referred to as the target vehicle travel distance) is calculated. The travel distance of the target vehicle can be calculated using the time when the host vehicle information is received and the vehicle speed pulse integrated value information included in the host vehicle information.

Furthermore, the received signal strength indicated by the received signal strength information received in S210 is associated with the GPS position indicated by the own vehicle location information included in the own vehicle information received in S210.
Then, the normalized received signal strength RSSI [dBm] is calculated by the following equation (1). In the following formula (1), RSSI _r [dBm] is the received signal strength indicated by the received signal strength information received in S210. P _t [dBm] is the transmission power indicated by the transmission power information included in the host vehicle information received in S210. RSSI _n [dBm] is a normalized received signal strength RSSI (hereinafter referred to as normalized received signal strength RSSI _n ).

RSSI _n = RSSI _r − P _t (1)
For example, when the transmission power P _t = 10 dBm and the received signal strength RSSI _r = −20 dBm, the normalized received signal strength RSSI _n = −30 dBm.

Then, a correspondence relationship between the normalized received signal strength RSSI _n and the target vehicle movement distance from the time when the host vehicle information of the target vehicle is first received to the present time is created as the probe trajectory. Note that coordinate values (for example, latitude and longitude) indicating the GPS position are associated with the normalized received signal strength RSSI _n . That is, the probe trajectory indicates not only the correspondence relationship between the target vehicle movement distance and the normalized received signal strength RSSI _n , but also the correspondence relationship between the target vehicle movement distance and the GPS position.

  Thereafter, in S230, from the reference trajectory information stored in the RAM 63, the information related to the reference station 2 that transmitted the received signal strength information received in S210 and related to the same vehicle type as the target vehicle is acquired.

The reference trajectory includes a distance (hereinafter referred to as a reference movement distance) traveled on a road near the reference station 2 on the road near the reference station 2 and a probe amount (in this embodiment, normalized in the present embodiment). It shows a correspondence relationship with the received signal strength RSSI _n ) (see FIG. 8). Also, a coordinate value for specifying a position (hereinafter referred to as a position coordinate value) is associated with the normalized received signal strength RSSI _n of the reference trajectory. That is, the reference trajectory indicates not only the correspondence between the reference movement distance and the normalized received signal strength RSSI _n , but also the correspondence between the reference movement distance and the position coordinate value.

  The reference trajectory information of the reference station 2 is provided for each vehicle type, each traveling direction, and each lane. The traveling direction is used to distinguish whether the vehicle is traveling in the up lane or the down lane of the road.

  The reference trajectory has the maximum probe amount at a point closest to the reference station 2 on the road near the reference station 2. Note that the reference trajectory does not necessarily have a gradual decrease in the probe amount as the distance from the point closest to the reference station 2 is reached, and may have a maximum point reflecting reflection or diffraction from surrounding buildings.

  In addition, the reference trajectories of the plurality of reference stations 2 are provided so that the target areas do not overlap with the reference trajectories of the different reference stations 2, and borders road branches (for example, intersections) set in advance on the map. Is divided as

  In S240, the probe trajectory created in S220 is superimposed on the reference trajectory indicated by the reference trajectory information acquired in S230 (see FIG. 9), and the degree of coincidence is equal to or higher than a preset trajectory coincidence determination value. It is determined whether or not there is a matching part. Here, if there is no matching part with a matching degree equal to or higher than the locus matching determination value (S240: NO), the process proceeds to S280. On the other hand, when there is a part that matches with a degree of coincidence equal to or greater than the trajectory coincidence determination value (S240: YES), in S250, the movement distance TD from the arbitrary feature point CP to the current time in the reference trajectory (see FIG. 9). Reference) is calculated. The feature point CP is a point at which the probe amount becomes, for example, maximum, minimum, maximum, or minimum.

  In S260, based on the movement distance TD from the feature point CP to the current time, a position coordinate value corresponding to the movement distance TD is extracted from the reference locus, and the position indicated by the position coordinate value is specified as the current position of the target vehicle. . Thereafter, in S270, positioning information is created, and this positioning information is transmitted to the reference station 2 that has transmitted the received signal strength information received in S210, and the process proceeds to S280. The positioning information includes target vehicle position information indicating the current position specified in S260 and vehicle identification information included in the own vehicle information received in S210.

  In S280, based on the current position of the target vehicle and the map data stored in the map data storage device 52, it is determined whether or not the target vehicle has reached the locus division point. The trajectory segmentation point is a lane boundary in a road with multiple lanes on one side, or a road branch (for example, an intersection) on a map. In S280, the position indicated by the host vehicle position information included in the host vehicle information received in S210 or the position calculated in S260 is used as the current position of the target vehicle.

  Here, when the target vehicle has not reached the trajectory division point (S280: NO), the server-side transmission / reception process is temporarily ended. On the other hand, when the target vehicle reaches the trajectory division point (S280: YES), the vehicle identification information included in the own vehicle information received in S210 is added to the probe trajectory created in S220 in S290, and the vehicle The probe trajectory with the identification information added is stored in the RAM 63.

  In S300, the accuracy (hereinafter referred to as target vehicle location accuracy) indicated by the location accuracy information included in the host vehicle information received in S210 is less than a preset update determination value (in this embodiment, for example, 10 cm). Determine whether or not.

Here, when the target vehicle position accuracy is equal to or higher than the update determination value (S300: NO), the server-side transmission / reception process is temporarily ended. On the other hand, when the target vehicle position accuracy is less than the update determination value (S300: YES), a reference trajectory having the same reference station, vehicle type, lane, and traveling direction as the probe trajectory created in S220 is obtained in S310. Updating is performed using the created probe trajectory, and the server-side transmission / reception process is temporarily terminated. Specifically, in this embodiment, for example, the probe trajectories created so far are classified by those having the same reference station, vehicle type, lane, and traveling direction, and the probe trajectory normalized reception signal is classified for each classified probe trajectory. An average value of the intensity RSSI _n is calculated, and this average value is used as a reference locus. However, the average value is calculated after excluding probe trajectories whose variance is equal to or greater than a preset exclusion determination value. If there is no reference trajectory having the same reference station, vehicle type, lane, and traveling direction, the probe trajectory created in S220 is stored in the RAM 63 as a new reference trajectory.

In the wireless positioning system 1 configured as described above, the direct wireless communication device 11 of the reference station 2 receives vehicle speed pulse integrated value information included in the own vehicle information from the in-vehicle device 3 by direct wireless communication. Then, the reference station 2 detects the received signal strength RSSI when the host vehicle information is received (S120). Further, the RAM 63 of the management server 4 has the normalized received signal strength RSSI _n and the distance traveled on this road from the point closest to the reference station 2 on the road near the reference station 2 (the above-mentioned reference movement distance, The reference trajectory information indicating the reference trajectory in which two or more correspondences are set is stored.

And the management server 4 produces the probe locus | trajectory which shows the corresponding relationship of several normalization received signal strength RSSI _n and several target vehicle moving distance (S220). Thereafter, the management server 4 compares the reference trajectory with the probe trajectory to determine the correspondence between the reference travel distance and the target vehicle travel distance (S240). Further, the management server 4 determines the current position of the in-vehicle device 3 based on the correspondence relationship between the reference moving distance and the target vehicle moving distance and the detected current normalized received signal strength RSSI _n (S250, S260). Then, the reference station 2 transmits positioning information indicating the current position of the in-vehicle device 3 to the in-vehicle device 3 (S270).

  In the wireless positioning system 1 configured as described above, the reference station 2 detects the received signal strength RSSI when data transmitted from the in-vehicle device 3 is directly received by wireless communication, so that the current position of the in-vehicle device 3 is determined. Can be determined. For this reason, according to the wireless positioning system 1, it is possible to perform positioning of the vehicle on which the in-vehicle device 3 is mounted regardless of the individual difference in the detection performance of the received signal strength RSSI in the in-vehicle device 3. Moreover, since the management server 4 performs the process of measuring the current position of the in-vehicle device 3, it is not necessary for the in-vehicle device 3 to measure its current position, and the processing load on the in-vehicle device 3 can be reduced.

  The direct wireless communication device 11 of the reference station 2 is fixedly installed at a preset installation position, and the reference movement distance in the reference trajectory information is the position on the road laid near the reference station 2. It is information to show. The vehicle speed pulse integrated value information transmitted by the in-vehicle device 3 is information that can be used to calculate the travel distance traveled by the host vehicle on the road laid near the reference station 2. Thereby, the vehicle-mounted device 3 of the host vehicle can determine the current position of the vehicle-mounted device 3 by directly performing wireless communication with one reference station 2. This is because the position of the own vehicle is limited to the road laid near the reference station 2.

The direct wireless communication device 11 of the reference station 2 further receives transmission power information indicating transmission power when the in-vehicle device 3 transmits the own vehicle information (vehicle speed pulse integrated value information) from the in-vehicle device 3 by direct wireless communication. To do. Then, the reference station 2 detects the received signal strength RSSI when the host vehicle information is received (S120). Further, the management server 4 uses the transmission power indicated by the transmission power information and the detected received signal strength RSSI to reflect the power that decreases before the data transmitted from the in-vehicle device 3 is received by the reference station 2. Calculated received signal strength RSSI _n is calculated, and this normalized received signal strength RSSI _n is employed to create a probe trajectory (S220).

  Thereby, even if it is a case where the transmission power at the time of the vehicle-mounted apparatus 3 transmitting data differs for every vehicle-mounted apparatus 3, generation | occurrence | production of the situation where positioning accuracy fluctuates greatly with transmission power can be suppressed.

  Further, the management server 4 updates the reference trajectory information using the created probe trajectory (S300). Thus, even when the wireless reception status of the reference station 2 changes due to a change in the surrounding situation of the reference station 2, the reference trajectory information can be corrected in response to this change.

  Further, the reference trajectory information of the reference station 2 is provided for each road lane and for each of a plurality of areas divided by a road branch set in advance on the map. The direct wireless communication device 11 of the reference station 2 further receives own vehicle position information indicating the current position of the in-vehicle device 3 from the in-vehicle device 3 by direct wireless communication. Then, the management server 4 determines whether or not the in-vehicle device 3 has reached the lane boundary or road branch based on the own vehicle position information (S280), and the in-vehicle device 3 has reached the lane boundary or road branch. (S280: YES), the reference trajectory information is updated using the created probe trajectory (S310). Thereby, it is possible to suppress the occurrence of a situation in which the reference trajectory information is updated using probe trajectories created for different lanes or different areas.

  Further, in the reference trajectory information, two or more correspondences between the position coordinate value indicating the current position detected by the in-vehicle device 3 and the reference movement distance are set. The direct wireless communication device 11 of the reference station 2 further receives position accuracy information indicating the accuracy of the position of the in-vehicle device 3 from the in-vehicle device 3 by direct wireless communication. Then, the management server 4 determines whether or not the accuracy (target vehicle location accuracy) indicated by the location accuracy information is less than a preset update determination value (S300), and the target vehicle location accuracy is less than the update determination value. In this case (S300: YES), the reference trajectory information is updated using the created probe trajectory (S310). As a result, it is possible to suppress the occurrence of a situation in which the reference trajectory information is updated using a probe trajectory with low positional accuracy of the position coordinate value.

  In the embodiment described above, the reference station 2 and the management server 4 are the wireless communication device in the present invention, the in-vehicle device 3 is the mobile communication device in the present invention, the direct wireless communication device 11 is the information receiving means in the present invention, and the processing of S120 is The first detection means, RAM 63 in the present invention is a reference information storage means in the present invention.

  The process of S220 is the first creation means in the present invention, the process of S240 is the first correspondence determining means in the present invention, the processes of S250 and S260 are the first position determining means in the present invention, and the process of S270 is in the present invention. The processing of the position transmitting unit, S280, S300, and S310 is the reference information updating unit in the present invention.

(Second Embodiment)
A second embodiment of the present invention will be described below with reference to the drawings.
As shown in FIG. 10, the wireless positioning system 101 of the present embodiment includes a plurality of reference stations 102 (two reference stations 102 a and 102 b shown in FIG. 10) that are installed near a road and perform direct wireless communication, and an automobile. And an in-vehicle device 103 (three in-vehicle devices 103a, 103b, and 103c are shown in FIG. 10) that perform direct wireless communication.

As illustrated in FIG. 11, the reference station 102 includes a direct wireless communication device 111, a map data storage device 112, and a control unit 113.
The direct wireless communication device 111 performs direct wireless communication with the in-vehicle device 103. The map data storage device 112 stores map data in the same manner as the map data storage device 52 of the first embodiment.

  The control unit 113 includes a CPU 121, a ROM 122, and a RAM 123, and directly controls the wireless communication device 111 when the CPU 121 executes a process based on a program stored in the ROM 122. In addition, the RAM 123 of the control unit 112 stores reference trajectories related to the reference station 102 on which the control unit 112 is mounted, classified by vehicle type, lane, and traveling direction.

The in-vehicle device 103 includes a vehicle speed sensor 31, a position detector 32, a direct wireless communication device 33, and a control unit 34 as in the in-vehicle device 3 of the first embodiment (see FIG. 3).
In the wireless positioning system 101 configured as described above, the reference station 102 performs reference station side transmission / reception processing, and the in-vehicle device 103 performs vehicle side transmission / reception processing.

The vehicle side transmission / reception processing executed by the in-vehicle device 103 is the same as the vehicle side transmission / reception processing executed by the in-vehicle device 3 of the first embodiment.
Next, the reference station side transmission / reception processing procedure executed by the CPU 121 of the reference station 102 will be described. This reference station side transmission / reception process is a process repeatedly executed during the operation of the CPU 121.

  When this reference station side transmission / reception process is executed, the CPU 121 first determines whether or not the host vehicle information is received from the in-vehicle device 103 in S410 as shown in FIG. Here, when the host vehicle information is not received (S410: NO), the reference station side transmission / reception process is temporarily ended.

  On the other hand, when the host vehicle information is received (S410: YES), the received signal strength RSSI of the received host vehicle information is detected at S420. In S430, a probe trajectory is created in the same manner as in S220 of the first embodiment. Further, at S440, from the reference trajectory information stored in the RAM 123, information related to the same vehicle type as the vehicle (hereinafter referred to as the target vehicle) specified by the vehicle identification information included in the host vehicle information received at S410 is acquired. To do.

  Thereafter, in S450, in the same manner as in S240 of the first embodiment, the probe trajectory created in S430 is superimposed on the reference trajectory indicated by the reference trajectory information acquired in S440, and a preset trajectory matching determination value is set. It is determined whether or not there is a matching part with the above matching degree.

  Here, if there is no matching part with a matching degree equal to or higher than the locus matching determination value (S450: NO), the process proceeds to S490. On the other hand, when there is a part that matches with a degree of coincidence equal to or higher than the trajectory coincidence determination value (S450: YES), in S460, as in S250 of the first embodiment, an arbitrary feature point CP in the reference trajectory. The travel distance TD from to the present time is calculated.

  In S470, the current position of the target vehicle is calculated in the same manner as in S260 of the first embodiment. Thereafter, in S480, positioning information is created in the same manner as in S270 of the first embodiment, the positioning information is directly transmitted to the wireless communication device 111, and the process proceeds to S490.

  Then, when the process proceeds to S490, the target vehicle has reached the trajectory division point based on the current position of the target vehicle and the map data stored in the map data storage device 112, as in S280 of the first embodiment. Determine whether or not.

  Here, when the target vehicle has not reached the trajectory division point (S490: NO), the reference station side transmission / reception process is temporarily ended. On the other hand, when the target vehicle reaches the trajectory division point (S490: YES), the probe trajectory is stored in the RAM 123 in S500 in the same manner as in S290 of the first embodiment. In S510, as in S300 of the first embodiment, the accuracy (hereinafter referred to as target vehicle location accuracy) indicated by the location accuracy information included in the host vehicle information received in S410 is less than a preset update determination value. It is determined whether or not.

  Here, if the target vehicle position accuracy is equal to or higher than the update determination value (S510: NO), the reference station side transmission / reception process is temporarily ended. On the other hand, if the target vehicle position accuracy is less than the update determination value (S510: YES), in S520, the reference trajectory is updated by updating the reference trajectory in the same manner as in S310 of the first embodiment. finish.

In the wireless positioning system 101 configured as described above, the direct wireless communication device 111 of the reference station 102 receives vehicle speed pulse integrated value information included in the own vehicle information from the in-vehicle device 103 by direct wireless communication. Then, the reference station 2 detects the received signal strength RSSI when the host vehicle information is received (S420). Further, the RAM 123 of the reference station 102 has a correspondence relationship between the normalized received signal strength RSSI _n and the distance (reference movement distance) traveled on the road near the reference station 102 on the road near the reference station 102 as a base point. Reference trajectory information indicating a reference trajectory set at a point or more is stored.

Then, the reference station 102 creates a probe trajectory indicating a correspondence relationship between the plurality of normalized received signal strengths RSSI _n and the plurality of target vehicle movement distances (S430). Thereafter, the reference station 102 compares the reference trajectory with the probe trajectory to determine the correspondence between the reference travel distance and the target vehicle travel distance (S450). Further, the reference station 102 determines the current position of the in-vehicle device 103 based on the correspondence relationship between the reference moving distance and the target vehicle moving distance and the detected current normalized received signal strength RSSI _n (S460, S470). ). Then, the reference station 102 transmits positioning information indicating the current position of the in-vehicle device 103 to the in-vehicle device 3 (S480).

  In the wireless positioning system 101 configured in this way, the reference station 102 detects the received signal strength RSSI when data transmitted from the in-vehicle device 103 is directly received by wireless communication, so that the current position of the in-vehicle device 103 is determined. Can be determined. For this reason, according to the wireless positioning system 101, positioning of the vehicle on which the in-vehicle device 103 is mounted can be performed regardless of the individual difference in the detection performance of the received signal strength RSSI in the in-vehicle device 103. Further, since the reference station 102 performs the process of measuring the current position of the in-vehicle device 103, the in-vehicle device 103 does not need to measure its current position, and the processing load on the in-vehicle device 103 can be reduced.

  In the embodiment described above, the reference station 102 is the wireless communication device according to the present invention, the in-vehicle device 103 is the mobile communication device according to the present invention, the direct wireless communication device 111 is the information receiving means according to the present invention, and the processing of S420 is 1 detection means and RAM 123 are reference information storage means in the present invention.

  Further, the process of S430 is the first creation means in the present invention, the process of S450 is the first correspondence determining means in the present invention, the processes of S460 and S470 are the first position determining means in the present invention, and the process of S480 is in the present invention. The processing of the position transmitting means, S490, S510, and S520 is the reference information updating means in the present invention.

(Third embodiment)
A third embodiment of the present invention will be described below with reference to the drawings. In the third embodiment, parts different from the first embodiment will be described.

As in the first embodiment, the wireless positioning system 1 according to the third embodiment includes a plurality of reference stations 2, an in-vehicle device 3, and a management server 4.
First, the reference station 2 according to the third embodiment is different from the first embodiment in that the reference station 2 has a function of periodically transmitting a wireless beacon including identification information of the reference station 2 itself to surrounding vehicles by a direct wireless communication function.

  Moreover, the vehicle-mounted apparatus 3 of 3rd Embodiment differs from 1st Embodiment by the point to which the wide area radio | wireless communication apparatus 35 was added, as shown in FIG. The wide area wireless communication device 35 performs data communication with the management server 4 via the wide area wireless communication network NW.

Moreover, the vehicle-mounted apparatus 3 of 3rd Embodiment differs from 1st Embodiment by the point by which the vehicle side transmission / reception process was changed.
Here, the procedure of the vehicle side transmission / reception process which CPU41 of the vehicle-mounted apparatus 3 of 3rd Embodiment performs is demonstrated.

The vehicle side transmission / reception process of the third embodiment is different from the first embodiment in that the processes of S610 to S700 are added.
That is, when this vehicle side transmission / reception process is executed, as shown in FIG. 14, the CPU 41 first determines in S610 whether the wide area wireless communication device 35 is connected to the management server 4 so as to be able to perform data communication. To do. If it is not connected to the management server 4 (S610: NO), the process proceeds to S630. On the other hand, when connected to the management server 4 (S610: YES), in S620, in the vicinity of the road on which the vehicle is traveling, a preset distance from the current position (for example, 1 km in this embodiment). ) The reference trajectory information indicating the reference trajectory for the reference station 2 existing within is acquired from the management server 4, stored in the RAM 43, and the process proceeds to S630.

  In S630, it is determined whether a wireless beacon is detected. If no wireless beacon is detected (S630: NO), the process proceeds to S10. On the other hand, if a radio beacon is detected (S630: YES), the received signal strength RSSI of the detected radio beacon is detected at S640, and the vehicle from the time when the radio beacon is first detected at S650. Is calculated. In S660, a probe trajectory indicating the correspondence relationship between the received signal strength RSSI and the movement distance from the time when the first wireless beacon is detected to the current time is created, and the process proceeds to S10.

  If the positioning information is not received in S40 (S40: NO), it is determined in S670 whether or not a preset switching determination time has elapsed since the vehicle information was transmitted. Here, when the switching determination time has not elapsed (S670: NO), the vehicle side transmission / reception process is temporarily ended.

  On the other hand, when the switching determination time has elapsed (S670: YES), in S680, similar to S240 in the first embodiment, created in S660 on the reference trajectory indicated by the reference trajectory information acquired in S620. The probe trajectories are overlapped, and it is determined whether or not there is a matching part with a degree of coincidence equal to or higher than a preset trajectory coincidence determination value.

  Here, if there is no matching part with a degree of coincidence equal to or greater than the locus coincidence determination value (S680: NO), the vehicle side transmission / reception process is temporarily ended. On the other hand, if there is a part that matches with a degree of coincidence equal to or greater than the trajectory match determination value (S680: YES), in S690, as in S250 of the first embodiment, an arbitrary feature point CP in the reference trajectory. The travel distance TD from to the present time is calculated.

In S700, the current position of the target vehicle is calculated in the same manner as in S260 of the first embodiment, and the vehicle-side transmission / reception process is temporarily terminated.
In the wireless positioning system 1 configured as described above, the direct wireless communication device 33 of the in-vehicle device 3 receives the wireless beacon transmitted from the reference station 2 by direct wireless communication. And the vehicle equipment 3 detects reception signal strength RSSI when a radio beacon is received (S640). The in-vehicle device 3 acquires reference trajectory information from the management server 4 (S620).

  The in-vehicle device 3 calculates the moving distance of the host vehicle from the time when the wireless beacon is first detected (S650), and creates a probe locus indicating the correspondence between the received signal strength RSSI and the moving distance (S660). Thereafter, the in-vehicle device 3 compares the reference trajectory with the probe trajectory to determine the correspondence between the reference travel distance and the travel distance of the host vehicle (S680). Furthermore, the in-vehicle device 3 determines the current position of the in-vehicle device 3 based on the correspondence relationship between the reference moving distance and the moving distance of the host vehicle and the detected current received signal strength RSSI (S690, S700). .

  According to the wireless positioning system 1 configured in this way, the in-vehicle device 3 can measure its current position, and the in-vehicle device 3 is compared with the case of acquiring positioning information from the reference station 2 and the management server 4. Thus, the current position of the user can be specified at an early stage.

  In the embodiment described above, the reference station 2 is the first wireless communication device in the present invention, the in-vehicle device 3 is the second wireless communication device in the present invention, the direct wireless communication device 33 is the second wireless communication means in the present invention, and the processing of S640. Is the second detection means in the present invention.

  The process of S620 is the reference information acquisition means in the present invention, the process of S650 is the distance measuring means in the present invention, the process of S660 is the second creating means in the present invention, and the process of S680 is the second correspondence determining means in the present invention. , S690 and S700 are the second position determining means in the present invention.

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, As long as it belongs to the technical scope of this invention, a various form can be taken.
The functions of one component in the above embodiment may be distributed as a plurality of components, or the functions of a plurality of components may be integrated into one component. Further, at least a part of the configuration of the above embodiment may be replaced with a known configuration having the same function. Moreover, you may abbreviate | omit a part of structure of the said embodiment as long as a subject can be solved. In addition, at least a part of the configuration of the above embodiment may be added to or replaced with the configuration of the other embodiment. In addition, all the aspects included in the technical idea specified only by the wording described in the claim are embodiment of this invention.

  DESCRIPTION OF SYMBOLS 1,101 ... Wireless positioning system, 2,102 ... Reference station, 3,103 ... In-vehicle device, 4 ... Management server, 11, 33, 111 ... Direct wireless communication device, 63, 123 ... RAM

Claims (8)

A wireless communication device (2, 4, 102) having a function of directly receiving wireless communication data transmitted from a mobile communication device (3, 103) mounted on a mobile body and performing wireless communication,
Information receiving means (11, 111) for receiving first relative distance related information, which is information related to the relative distance between the mobile communication device and the wireless communication device, directly from the mobile communication device by wireless communication; ,
First detection means (S120, S420) for detecting a wireless reception status when the information receiving means receives the first relative distance related information;
Criteria for storing correspondence relationship reference information in which two or more correspondence relationships between the wireless reception status detected by the first detection means and location related information that is information related to the location of the mobile communication device are set. Information storage means (63, 123);
First creation for creating first correspondence information indicating correspondence between the plurality of wireless reception statuses detected by the first detection means and the plurality of first relative distance related information received by the information reception means Means (S220, S430);
A first correspondence determining means (S240, S450) for determining a correspondence between the position related information and the first relative distance related information by comparing the correspondence reference information with the first correspondence information; ,
Based on the correspondence relationship between the position related information and the first relative distance related information determined by the first correspondence relationship determining means, and the current wireless reception status detected by the first detection means, First position determining means (S250, S260, S460, S470) for determining a current position of the mobile object which is a current position of the mobile communication device;
A wireless communication apparatus comprising: position transmission means (S270, S480) for transmitting positioning information indicating the current position of the mobile body determined by the first position determination means to the mobile communication apparatus. The information receiving means is fixedly installed at a preset installation position,
The position related information in the correspondence relationship criterion information is information indicating a position on a road laid near the information receiving means,
The first relative distance related information transmitted by the mobile communication device is information capable of calculating a travel distance traveled by the mobile body on a road laid near the information receiving means. The wireless communication apparatus according to claim 1. The information receiving means further receives transmission power information indicating transmission power when the mobile communication device transmits the first relative distance related information from the mobile communication device by direct wireless communication,
The first detection means detects received power when the first relative distance related information is received as the wireless reception status,
The first creation means uses the transmission power and the reception power, and a reduced power reflection value reflecting a power that decreases before the data transmitted from the mobile communication device is received by the wireless communication device The wireless communication apparatus according to claim 1, wherein the first correspondence relationship information is created by calculating the reflected power reflected value as the wireless reception status. Reference information update means (S280, S300, S310, S490, S510, S520) for updating the correspondence relation reference information using the first correspondence relation information created by the first creation means is provided. The radio | wireless communication apparatus of any one of Claims 1-3. The correspondence reference information is provided for each lane of the road, and is provided for each of a plurality of areas divided by a road branch set in advance on the map,
The information receiving means further receives current position information indicating a current position of the mobile communication device directly from the mobile communication device by wireless communication,
The reference information updating means determines whether or not a first preset update condition indicating that the mobile communication device is located at a boundary of the lane or the road branch is satisfied based on the current position information. 5. The wireless communication according to claim 4, wherein, when it is determined that the first update condition is satisfied, the correspondence reference information is updated using the first correspondence information. apparatus. The correspondence relationship criterion information further includes two or more correspondence relationships between the detected location information indicating the current location detected by the mobile communication device and the location related information,
The information receiving means further receives accuracy determination information capable of determining the level of accuracy of the position of the mobile communication device by direct wireless communication from the mobile communication device,
The reference information update unit determines whether a second update condition set in advance indicating that the position accuracy of the mobile communication device is high is satisfied based on the accuracy determination information, and The wireless communication apparatus according to claim 4 or 5, wherein when it is determined that an update condition is satisfied, the correspondence relationship reference information is updated using the first correspondence relationship information. A first wireless communication device (2, 4, 102), which is the wireless communication device according to claim 1, and a second wireless communication device (3, 103), which is the mobile communication device according to claim 1. A wireless positioning system (1, 101) characterized by comprising: The wireless positioning system according to claim 7, wherein the wireless communication device (3) is used as the second wireless communication device,
Second wireless communication means (33) for directly receiving data transmitted from the first wireless communication device by wireless communication;
Second detection means (S640) for detecting a wireless reception status by the second wireless communication means;
Reference information acquisition means (S620) for acquiring the correspondence relationship reference information from the first wireless communication device;
Distance measuring means (S650) for measuring second relative distance related information which is information related to a relative distance between the first wireless communication device and the wireless communication device;
Second correspondence information indicating a correspondence relationship between the plurality of wireless reception statuses detected by the second detection means and the plurality of second relative distance related information measured by the distance measurement means is generated. Creating means (S660);
A second correspondence determining means (S680) for determining a correspondence between the position related information and the second relative distance related information by comparing the correspondence reference information with the second correspondence information;
Based on the correspondence relationship between the position related information and the second relative distance related information determined by the second correspondence relationship determining means, and the current wireless reception status detected by the second detection means, A wireless communication apparatus comprising: second position determining means (S690, S700) for determining a current position in the wireless communication apparatus.

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