JP6156736B2 - Wireless device - Google Patents

Description

  The present invention relates to communication technology, and more particularly to a radio apparatus that broadcasts a signal including predetermined information.

  The road-to-vehicle communication reception processing system receives information about a plurality of intersections from a roadside machine, and generates a plurality of routes at each of the plurality of intersections. Further, the road-to-vehicle communication reception processing system stores only intersection information of an intersection corresponding to the determined travel route by determining a travel route on which the vehicle travels from a plurality of routes (see, for example, Patent Document 1). ).

JP 2012-252649 A

  When determining the travel route on which the host vehicle is traveling based on the traveling direction of the host vehicle, even if the host vehicle is traveling on the second road parallel to the first road, There is a risk that it is erroneously determined that the vehicle is traveling on the road.

  This invention is made | formed in view of such a condition, The objective is to provide the technique which specifies the driving | running route which the own vehicle is drive | working.

  In order to solve the above problems, a wireless device according to an aspect of the present invention is a wireless device that can be mounted on a vehicle, is a packet signal from another wireless device, and is discretely defined on a route. A receiving unit that receives a packet signal including position information of a plurality of nodes, a position information of a first node of the plurality of nodes, and a node next to the first node from the packet signal received by the receiving unit An extraction unit for extracting the position information of the second node, an acquisition unit for acquiring the position information of the vehicle on which the wireless device is mounted, and (1) the position information of the first node extracted by the extraction unit, A first vector toward the position information acquired in the acquisition unit, (2) a second vector toward the position information of the second node extracted in the extraction unit from the position information acquired in the acquisition unit, (3) in the acquisition unit A derivation unit that derives a traveling direction vector that is a change in the obtained position information, and an angle formed by the first vector derived in the derivation unit and the traveling direction vector is equal to or less than a threshold value, and the second derived in the derivation unit. And a determination unit that determines that the vehicle is on the route when the angle formed by the vector and the traveling direction vector is equal to or less than a threshold value.

  It should be noted that any combination of the above-described constituent elements and a conversion of the expression of the present invention between a method, an apparatus, a system, a recording medium, a computer program, etc. are also effective as an aspect of the present invention.

  According to the present invention, it is possible to specify a travel route on which the host vehicle is traveling.

It is a figure which shows the structure of the communication system which concerns on Example 1 of this invention. It is a figure which shows another structure of the communication system which concerns on Example 1 of this invention. It is a figure which shows the structure of the communication system used as the comparison object of the communication system which concerns on Example 1 of this invention. It is a figure which shows the structure of the base station apparatus of FIG. FIGS. 5A to 5D are diagrams showing frame formats defined in the communication system of FIGS. FIGS. 6A and 6B are diagrams illustrating a format of a packet signal defined in the communication system of FIGS. It is a figure which shows the structure of the terminal device of FIG. It is a figure which shows the structure of the filtering part of FIG. It is a figure which shows the process outline | summary of the derivation | leading-out part of FIG. FIGS. 10A to 10D are diagrams illustrating an outline of processing of the determination unit in FIG. It is a flowchart which shows the procedure of the reception process by the terminal device of FIG. It is a flowchart which shows another procedure of the reception process by the terminal device of FIG. FIGS. 13A to 13B are diagrams illustrating an outline of processing of the communication system according to the second embodiment of the present invention. FIGS. 14A and 14B are diagrams illustrating an outline of a node setting process performed by the generation unit according to the second embodiment of this invention. FIGS. 15A to 15C are diagrams illustrating packet signal formats defined in the terminal device according to the second embodiment of the present invention. It is a figure which shows the structure of the filtering part of Example 2 of this invention. FIGS. 17A and 17B are diagrams illustrating an outline of processing of the on-path determination unit in FIG. 18A to 18C are diagrams illustrating an outline of processing of the route intersection determination unit in FIG. It is a figure which shows the image displayed on the notification part of Example 2 of this invention. It is a flowchart which shows the procedure of the reception process by the terminal device of Example 2 of this invention.

Example 1
Prior to specific description of the embodiments of the present invention, the underlying knowledge will be described. Embodiment 1 of the present invention relates to a communication system that executes vehicle-to-vehicle communication between terminal devices mounted on a vehicle and also executes road-to-vehicle communication from a base station device installed at an intersection or the like to a terminal device. Such a communication system is also called ITS (Intelligent Transport Systems). The communication system uses an access control function called CSMA / CA (Carrier Sense Multiple Access Collision Aviation) as well as a wireless LAN (Local Area Network) compliant with a standard such as IEEE 802.11. Therefore, the same radio channel is shared by a plurality of terminal devices. On the other hand, in ITS, it is necessary to transmit information to an unspecified number of terminal devices. In order to efficiently perform such transmission, the communication system broadcasts a packet signal.

  That is, as inter-vehicle communication, the terminal device broadcasts a packet signal that stores information such as the speed or position of the vehicle. In addition, the other terminal device receives the packet signal and recognizes the approach of the vehicle based on the above-described information. Here, in order to reduce interference between road-vehicle communication and vehicle-to-vehicle communication, the base station apparatus repeatedly defines a frame including a plurality of subframes. The base station apparatus selects any of a plurality of subframes for road-to-vehicle communication, and broadcasts a packet signal in which control information and the like are stored during the period of the head portion of the selected subframe.

  The control information includes information related to a period for the base station apparatus to broadcast the packet signal (hereinafter referred to as “road vehicle transmission period”). The terminal device specifies a road and vehicle transmission period based on the control information, and broadcasts a packet signal by the CSMA method in a period other than the road and vehicle transmission period (hereinafter referred to as “vehicle transmission period”). As a result, road-to-vehicle communication and vehicle-to-vehicle communication are time-division multiplexed. Note that a terminal device that cannot receive control information from the base station device, that is, a terminal device that exists outside the area formed by the base station device transmits a packet signal by the CSMA method regardless of the frame configuration.

  In road-to-vehicle communication, a terminal device may receive packet signals from a plurality of base station devices. At this time, the packet signal from the base station apparatus installed at the intersection that has already passed is unnecessary information, and the packet signal from the base station apparatus installed at the intersection scheduled to be passed is information that is necessary. If the packet signal from the former is discarded and only the packet signal from the latter is extracted, the information contained in the packet signal from the latter is accurately notified to the driver. Also, since only the packet signal from the latter is processed, the processing amount is reduced. Therefore, it is desired to easily and accurately extract the packet signal from the base station apparatus installed at the intersection scheduled to pass.

  Next, an outline of the present embodiment will be described. In this embodiment, position information of a plurality of nodes discretely defined on the path is included in the packet signal from the base station apparatus. The terminal device mounted on the vehicle has the position information of one node (hereinafter referred to as “first node”) and the position of the next node (hereinafter referred to as “second node”) from the received packet signal. Information is extracted and vehicle position information is acquired. The terminal device derives a first vector from the first node to the vehicle, a second vector from the vehicle to the second node, and a traveling direction vector that is a change in the position information of the vehicle. Further, the terminal device determines whether or not the terminal device exists on the route based on the relationship between the directions of these vectors. Since the determination is made based on the relationship of the vector orientation, simple and accurate identification is performed.

  FIG. 1 shows a configuration of a communication system 100 according to Embodiment 1 of the present invention. This corresponds to a case where one intersection is viewed from above. The communication system 100 includes a base station device 10, a first vehicle 12a, a second vehicle 12b, a third vehicle 12c, a fourth vehicle 12d, a fifth vehicle 12e, a sixth vehicle 12f, and a seventh vehicle 12g, collectively referred to as a vehicle 12. , The eighth vehicle 12h, and the network 202. Here, only the first vehicle 12 a is shown, but each vehicle 12 is equipped with a terminal device 14. An area 212 is formed around the base station apparatus 10, and an outside area 214 is formed outside the area 212.

  As shown in the drawing, the road that goes in the horizontal direction of the drawing, that is, the left and right direction, intersects the vertical direction of the drawing, that is, the road that goes in the up and down direction, at the center. Here, the upper side of the drawing corresponds to the direction “north”, the left side corresponds to the direction “west”, the lower side corresponds to the direction “south”, and the right side corresponds to the direction “east”. The intersection of the two roads is an “intersection”. The first vehicle 12a and the second vehicle 12b are traveling from left to right, and the third vehicle 12c and the fourth vehicle 12d are traveling from right to left. Further, the fifth vehicle 12e and the sixth vehicle 12f are traveling from the top to the bottom, and the seventh vehicle 12g and the eighth vehicle 12h are traveling from the bottom to the top.

  In the communication system 100, the base station apparatus 10 is fixedly installed at an intersection. The base station device 10 controls communication between terminal devices. The base station apparatus 10 receives a frame including a plurality of subframes based on a signal received from a GPS (Global Positioning System) satellite (not shown) or a frame formed by another base station apparatus 10 (not shown). Generate repeatedly. Here, the road vehicle transmission period can be set at the head of each subframe.

  The base station apparatus 10 selects a subframe in which the road and vehicle transmission period is not set by another base station apparatus 10 from among a plurality of subframes in the frame. The base station apparatus 10 sets a road and vehicle transmission period at the beginning of the selected subframe. The base station apparatus 10 notifies the packet signal in the set road and vehicle transmission period. In the road and vehicle transmission period, a plurality of packet signals may be notified. The packet signal includes, for example, accident information, traffic jam information, signal information, and the like. Note that the packet signal also includes information related to the timing when the road and vehicle transmission period is set and control information related to the frame.

  As described above, the terminal device 14 is mounted on the vehicle 12 and is movable. When receiving the packet signal from the base station apparatus 10, the terminal apparatus 14 estimates that the terminal apparatus 14 exists in the area 212. When the terminal device 14 exists in the area 212, the terminal device 14 generates a frame based on the control information included in the packet signal, in particular, the information on the timing when the road and vehicle transmission period is set and the information on the frame. As a result, the frame generated in each of the plurality of terminal devices 14 is synchronized with the frame generated in the base station device 10. The terminal device 14 notifies the packet signal in the vehicle transmission period that is a period different from the road and vehicle transmission period. Here, CSMA / CA is executed in the vehicle transmission period. On the other hand, when it is estimated that the terminal apparatus 14 exists outside the area 214, the terminal apparatus 14 notifies the packet signal by executing CSMA / CA regardless of the frame configuration. The terminal device 14 recognizes the approach of the vehicle 12 on which the other terminal device 14 is mounted based on the packet signal from the other terminal device 14.

  FIG. 2 shows another configuration of the communication system 100 according to the first embodiment of the present invention. A first base station apparatus 10a and a second base station apparatus 10b are installed on the road. The vehicle 12 is traveling from left to right. That is, the vehicle 12 is scheduled to pass through the intersection where the first base station apparatus 10a is already installed and through the intersection where the second base station apparatus 10b is installed. Therefore, the vehicle 12 does not need the packet signal from the first base station apparatus 10a, and needs the packet signal from the second base station apparatus 10b. Here, if the terminal device 14 mounted on the vehicle 12 stores all the information regarding the installation position of each base station device 10 and the route information of the road, from the current position to the next intersection to be passed. The installed base station apparatus 10 is specified. However, if these pieces of information are stored, the storage capacity becomes too large. Here, it is assumed that these pieces of information are not stored.

  When the packet signal transmitted from the second base station apparatus 10b includes information about a right turn, the position information of the node related to the right turn is also included in the packet signal. Here, the nodes are indicated as a first node 110a, a second node 110b, a third node 110c, and a fourth node 110d. A route including four nodes 110 is a route related to a right turn. The terminal device 14 mounted on the vehicle 12 recognizes that the vehicle 12 exists on the route relating to the right turn based on the positional information of the four nodes 110 included in the packet signal. When the vehicle 12 makes a right turn, the terminal device 14 processes information related to the right turn included in the received packet signal. A process for recognizing that the vehicle 12 exists on the route will be described later.

  FIG. 3 shows a configuration of a communication system 160 to be compared with the communication system 100 according to the first embodiment of the present invention. As described above, this is a process of using the traveling direction of the host vehicle in order to determine whether the host vehicle is traveling. The first vehicle 152a travels on the road where the base station device 150 is installed. On the other hand, the second vehicle 152b travels on a road parallel to the road where the base station device 150 is installed. The packet signal from base station apparatus 150 is received by first vehicle 152a and second vehicle 152b. When the traveling direction is used, it is determined in the first vehicle 152a and the second vehicle 152b that the road on which the base station device 150 is installed is the road on which the host vehicle is traveling. Such a determination is correct for the first vehicle 152a but incorrect for the second vehicle 152b. Therefore, it can be said that the determination to use the traveling direction of the host vehicle is not accurate.

  FIG. 4 shows the configuration of the base station apparatus 10. The base station apparatus 10 includes an antenna 20, an RF unit 22, a modem unit 24, a processing unit 26, a control unit 28, and a network communication unit 30. Further, the processing unit 26 includes a frame defining unit 32, a selecting unit 34, and a generating unit 36.

  The RF unit 22 receives a packet signal from a terminal device 14 (not shown) or another base station device 10 by the antenna 20 as a reception process. The RF unit 22 performs frequency conversion on the received radio frequency packet signal to generate a baseband packet signal. Further, the RF unit 22 outputs a baseband packet signal to the modem unit 24. In general, baseband packet signals are formed by in-phase and quadrature components, so two signal lines should be shown, but here only one signal line is shown for clarity. Shall be shown. The RF unit 22 includes an LNA (Low Noise Amplifier), a mixer, an AGC, and an A / D conversion unit.

  As a transmission process, the RF unit 22 performs frequency conversion on the baseband packet signal input from the modem unit 24 to generate a radio frequency packet signal. Further, the RF unit 22 transmits a radio frequency packet signal from the antenna 20 during the road-vehicle transmission period. The RF unit 22 also includes a PA (Power Amplifier), a mixer, and a D / A conversion unit.

  The modem unit 24 demodulates the baseband packet signal from the RF unit 22 as a reception process. Further, the modem unit 24 outputs the demodulated result to the processing unit 26. The modem unit 24 also modulates the data from the processing unit 26 as a transmission process. Further, the modem unit 24 outputs the modulated result to the RF unit 22 as a baseband packet signal. Here, since the communication system 100 corresponds to an OFDM (Orthogonal Frequency Division Multiplexing) modulation scheme, the modem unit 24 also performs FFT (Fast Fourier Transform) as reception processing and IFFT (Inverse Fast Forward) as transmission processing. Also execute.

  The frame defining unit 32 receives a signal from a GPS satellite (not shown), and acquires time information based on the received signal. In addition, since a well-known technique should just be used for acquisition of the information of time, description is abbreviate | omitted here. The frame defining unit 32 generates a plurality of frames based on the time information. For example, the frame defining unit 32 generates ten “100 msec” frames by dividing the “1 sec” period into ten on the basis of the timing indicated by the time information. By repeating such processing, the frame is defined to be repeated. The frame defining unit 32 may detect control information from the demodulation result and generate a frame based on the detected control information. Such processing corresponds to generating a frame synchronized with the timing of the frame formed by another base station apparatus 10.

  5A to 5D show frame formats defined in the communication system 100. FIG. FIG. 5A shows the structure of the frame. The frame is formed of N subframes indicated as the first subframe to the Nth subframe. This can be said that the terminal device 14 forms a frame by multiplexing a plurality of subframes that can be used for notification for a plurality of hours. For example, when the frame length is 100 msec and N is 8, a subframe having a length of 12.5 msec is defined. N may be other than 8. The description of FIGS. 5B to 5D will be described later and returns to FIG.

  The selection part 34 selects the sub-frame which should set a road and vehicle transmission period among several sub-frames contained in the flame | frame. More specifically, the selection unit 34 receives a frame defined by the frame defining unit 32. The selection unit 34 receives an instruction regarding the selected subframe via an interface (not shown). The selection unit 34 selects a subframe corresponding to the instruction. Apart from this, the selection unit 34 may automatically select a subframe. At this time, the selection unit 34 inputs a demodulation result from another base station device 10 or the terminal device 14 (not shown) via the RF unit 22 and the modem unit 24. The selection part 34 extracts the demodulation result from the other base station apparatus 10 among the input demodulation results. The selection unit 34 specifies the subframe that has not received the demodulation result by specifying the subframe that has received the demodulation result.

  This corresponds to specifying a subframe in which the road and vehicle transmission period is not set by another base station apparatus 10, that is, an unused subframe. When there are a plurality of unused subframes, the selection unit 34 selects one subframe at random. When there are no unused subframes, that is, when each of a plurality of subframes is used, the selection unit 34 acquires reception power corresponding to the demodulation result, and gives priority to subframes with low reception power. Select

  FIG. 5B shows a configuration of a frame generated by the first base station apparatus 10a. The first base station apparatus 10a sets a road and vehicle transmission period at the beginning of the first subframe. Moreover, the 1st base station apparatus 10a sets a vehicle transmission period following the road and vehicle transmission period in a 1st sub-frame. The vehicle transmission period is a period during which the terminal device 14 can notify the packet signal. That is, the first base station apparatus 10a can notify the packet signal in the road and vehicle transmission period which is the first period of the first subframe, and the terminal apparatus in the vehicle and vehicle transmission period other than the road and vehicle transmission period in the frame. It is specified that 14 can broadcast the packet signal. Furthermore, the first base station apparatus 10a sets only the vehicle transmission period from the second subframe to the Nth subframe.

  FIG.5 (c) shows the structure of the flame | frame produced | generated by the 2nd base station apparatus 10b. The second base station apparatus 10b sets a road and vehicle transmission period at the beginning of the second subframe. Also, the second base station apparatus 10b sets the vehicle transmission period from the first stage of the road and vehicle transmission period in the second subframe, from the first subframe and the third subframe to the Nth subframe. FIG. 5D shows a configuration of a frame generated by the third base station apparatus 10c. The third base station apparatus 10c sets a road and vehicle transmission period at the beginning of the third subframe. In addition, the third base station apparatus 10c sets the vehicle transmission period from the first stage of the road and vehicle transmission period in the third subframe, the first subframe, the second subframe, and the fourth subframe to the Nth subframe. As described above, the plurality of base station apparatuses 10 select different subframes, and set the road and vehicle transmission period at the head portion of the selected subframe. Returning to FIG. The selection unit 34 outputs the selected subframe number to the generation unit 36.

  The generation unit 36 receives a subframe number from the selection unit 34. The generation unit 36 sets a road and vehicle transmission period in the subframe of the received subframe number, and generates a packet signal to be notified during the road and vehicle transmission period. When a plurality of packet signals are transmitted in one road and vehicle transmission period, the generation unit 36 generates them. The packet signal is composed of control information and a payload. The control information includes a subframe number in which a road and vehicle transmission period is set. The payload includes, for example, accident information, traffic jam information, signal information, and the like. These data are acquired from the network 202 (not shown) by the network communication unit 30. The processing unit 26 broadcasts the packet signal to the modem unit 24 and the RF unit 22 during the road and vehicle transmission period. The control unit 28 controls processing of the entire base station device 10.

  6A to 6B show packet signal formats defined in the communication system 100. FIG. This can also be said to be a format of a packet signal generated by the generation unit 36. FIG. 6A shows the format of the packet signal. The common header of the packet signal corresponds to the control information described above. The common header includes a wireless device ID for identifying wireless devices such as the base station device 10 and the terminal device 14, a message ID for specifying a message type, a data transmission time, and the like. The message specific information of the packet signal corresponds to the above-described payload, and is shown in FIG. The message type of the message specific information is classified into road alignment information and service information. The road alignment information includes intersection position information and node position information. The service information includes signal lamp color information, walking presence information, regulation information, and the like.

  This configuration can be realized in terms of hardware by a CPU, memory, or other LSI of any computer, and in terms of software, it can be realized by a program loaded in the memory, but here it is realized by their cooperation. Draw functional blocks. Accordingly, those skilled in the art will understand that these functional blocks can be realized in various forms only by hardware, or by a combination of hardware and software.

  FIG. 7 shows the configuration of the terminal device 14. The terminal device 14 includes an antenna 50, an RF unit 52, a modem unit 54, a processing unit 56, and a control unit 58. The processing unit 56 includes a timing specifying unit 60, a transfer determining unit 62, a position information acquiring unit 64, a generating unit 66, a filtering unit 68, and a notification unit 70. The timing specifying unit 60 includes an extracting unit 72 and a carrier sensing unit 74. Including. The terminal device 14 can be mounted on the vehicle 12 as described above. The antenna 50, the RF unit 52, and the modem unit 54 perform the same processing as the antenna 20, the RF unit 22, and the modem unit 24 in FIG. Here, the difference will be mainly described.

  The modem unit 54 and the processing unit 56 receive a packet signal from another terminal device 14 or the base station device 10 (not shown) in the reception process. As described above, the modem unit 54 and the processing unit 56 receive a packet signal from the base station apparatus 10 during the road-to-vehicle transmission period, and receive packet signals from other terminal apparatuses 14 during the vehicle-to-vehicle transmission period. To do.

  When the demodulation result from the modem unit 54 is a packet signal from the base station apparatus 10 (not shown), the extraction unit 72 specifies the timing of the subframe in which the road and vehicle transmission period is arranged. In that case, the extraction part 72 estimates that it exists in the area 212 of FIG. The extraction unit 72 generates a frame based on the timing of the subframe and the content of the message header of the packet signal, specifically, the content of the road and vehicle transmission period length. Note that the generation of the frame only needs to be performed in the same manner as the frame defining unit 32 described above, and thus the description thereof is omitted here. As a result, the extraction unit 72 generates a frame synchronized with the frame formed in the base station device 10. When the notification source of the packet signal is another terminal device 14, the extraction unit 72 omits the synchronized frame generation process.

  On the other hand, when the extraction unit 72 has not received a packet signal from the base station apparatus 10, the extraction unit 72 estimates that the extraction unit 72 exists outside the area 214 in FIG. When it is estimated that the extraction unit 72 exists in the area 212, the extraction unit 72 selects the vehicle transmission period. When it is estimated that the extraction unit 72 exists outside the area 214, the extraction unit 72 selects a timing unrelated to the frame configuration. When the vehicle transmission period is selected, the extraction unit 72 outputs information on the frame and subframe timing and the vehicle transmission period to the carrier sense unit 74. When selecting the timing unrelated to the frame configuration, the extraction unit 72 instructs the carrier sense unit 74 to execute carrier sense.

  The carrier sense unit 74 receives information about the timing of the frames and subframes and the vehicle transmission period from the extraction unit 72. The carrier sense unit 74 determines the transmission timing by starting CSMA / CA within the vehicle transmission period. On the other hand, when the carrier sense unit 74 is instructed by the extraction unit 72 to execute carrier sense not related to the frame configuration, the carrier sense unit 74 performs transmission timing by executing CSMA / CA without considering the frame configuration. To decide. The carrier sense unit 74 notifies the modem unit 54 and the RF unit 52 of the determined transmission timing, and broadcasts the packet signal.

  The transfer determination unit 62 controls transfer of control information. The transfer determination unit 62 extracts information to be transferred from the control information. The transfer determination unit 62 generates information to be transferred based on the extracted information. Here, the description of this process is omitted. The transfer determination unit 62 outputs information to be transferred, that is, a part of the control information, to the generation unit 66.

  The position information acquisition unit 64 includes a GPS receiver, a gyroscope, a vehicle speed sensor, and the like (not shown), and the presence position of the vehicle 12 (not shown), that is, the vehicle 12 on which the terminal device 14 is mounted, by data supplied from them. The traveling direction, the moving speed, etc. (hereinafter collectively referred to as “position information”) are acquired. The existence position is indicated by latitude and longitude. Since a known technique may be used for these acquisitions, description thereof is omitted here. The position information acquisition unit 64 outputs the position information to the generation unit 66 and the filtering unit 68.

  The generation unit 66 receives position information from the position information acquisition unit 64 and receives part of the control information from the transfer determination unit 62. The generation unit 66 generates the included packet signal and broadcasts the generated packet signal via the modem unit 54, the RF unit 52, and the antenna 50 at the transmission timing determined by the carrier sense unit 74. This corresponds to inter-vehicle communication.

  The filtering unit 68 selects a packet signal to be processed by the notification unit 70 from among the packet signals received by the extraction unit 72, that is, packet signals from the base station device 10 and other terminal devices 14. Here, filtering is not performed on packet signals from other terminal apparatuses 14, but filtering is performed on packet signals from the base station apparatus 10. In particular, the filtering unit 68 selects a packet signal including information on a route on which the host vehicle (vehicle 12) is present from among the packet signals from the base station device 10. Specific processing of filtering will be described later. The filtering unit 68 outputs the selected packet signal to the notification unit 70. The filtering unit 68 also outputs packet signals from other terminal devices 14 to the notification unit 70.

  The notification unit 70 displays the contents of the received packet signal on a display (not shown) or the like. The notification unit 70 detects the approach of the other vehicle 12 based on the position information of the other terminal device 14 acquired from the filtering unit 68 and the position information input from the position information acquisition unit 64. The notification unit 70 notifies the driver of the approach of another vehicle 12 via a monitor or a speaker. Furthermore, the notification unit 70 notifies the driver of the packet signal received from the filtering unit 68 and included in the packet signal from the base station device 10 via a monitor or a speaker. An example of the information is as shown in the service information in FIG. Note that the notification unit 70 may execute another application program.

  FIG. 8 shows the configuration of the filtering unit 68. The filtering unit 68 includes an input unit 80, a position information extraction unit 82, a derivation unit 84, and a determination unit 86. The position information extraction unit 82 extracts position information included in the packet signal from the packet signal received by the extraction unit 72. Here, in particular, a packet signal from the base station apparatus 10 installed on a road including a route, and a packet signal including position information of a plurality of nodes 110 discretely defined on the route To be processed. The position information extraction unit 82 includes position information of one node 110 (hereinafter referred to as “start point node”) of the plurality of nodes 110 and a position of a node 110 subsequent to the start point node (hereinafter referred to as “end point node”). Extract information. In FIG. 2, if the start point node is the first node 110a, the end point node is the second node 110b. If the start node is the second node 110b, the end node is the third node 110c. In this way, the position information extraction unit 82 extracts a plurality of combinations while changing the combination of the start point node and the end point node. The input unit 80 acquires the position information measured by the position information acquisition unit 64. This corresponds to acquiring position information of the vehicle 12 on which the terminal device 14 is mounted.

  The derivation unit 84 receives a plurality of combinations from the position information extraction unit 82 and receives the position information of the vehicle 12 from the input unit 80. The deriving unit 84 derives a first vector 120 directed from the position information of the start point node toward the position information of the vehicle 12 with respect to one combination, and from the position information of the vehicle 12 toward the position information of the end point node. Two vectors 122 are derived. Further, the deriving unit 84 derives a traveling direction vector 124 toward the position information of the vehicle 12 from the past position information of the vehicle 12. The traveling direction vector 124 indicates a change in the position information of the vehicle 12.

  FIG. 9 shows a processing outline of the derivation unit 84. Here, in order to clarify the difference between the first vector 120, the second vector 122, and the traveling direction vector 124, a path 112 that is turned to the right is shown as an example. The path 112 is from the first node 110a to the fourth node 110d. Moreover, the vehicle 12 exists between the adjacent first node 110a and the second node 110b. In this case, the first node 110a corresponds to the start point node, and the second node 110b corresponds to the end point node. Based on the start point node and the end point node specified as described above, a first vector 120, a second vector 122, and a traveling direction vector 124 are derived as illustrated. Furthermore, the first vector 120 and the second vector 122 are derived for each combination while changing the start point node and the end point node. Returning to FIG.

  The determination unit 86 receives the first vector 120, the second vector 122, and the traveling direction vector 124 from the derivation unit 84. The determination unit 86 determines that an angle formed by the first vector 120 and the traveling direction vector 124 is equal to or less than a threshold value for one combination, and an angle formed by the second vector 122 and the traveling direction vector 124 is a threshold. When the value is equal to or smaller than the value, it is determined that the vehicle 12 exists on the route 112. When the determination unit 86 performs the above-described processing for each of the plurality of combinations and determines that the vehicle 12 is on the route 112 in any combination, the determination is finally made when the vehicle 12 is on the route 112. judge. When the vehicle 12 is stopped, the determination unit 86 performs the above-described process based on the traveling direction vector 124 immediately before the vehicle 12 stops.

  FIGS. 10A to 10D show an outline of processing of the determination unit 86. In FIG. 10A, the angle θ1 formed by the first vector 120 and the traveling direction vector 124 is equal to or smaller than the threshold value, and the angle θ2 formed between the traveling direction vector 124 and the second vector 122 is equal to or smaller than the threshold value. Therefore, it is determined that the vehicle 12 exists between the first node 110 a and the second node 110 b in the route 112, and the vehicle 12 is on the route 112. In FIG. 10B, the angle θ1 formed by the first vector 120 and the traveling direction vector 124 is larger than the threshold value, and the angle θ2 formed by the traveling direction vector 124 and the second vector 122 is larger than the threshold value. It is determined that the vehicle 12 is not on the route 112 (not traveling on the route 112).

  In FIG. 10C, the angle θ2 formed by the traveling direction vector 124 and the second vector 122 is equal to or smaller than the threshold value, but the angle θ1 formed by the first vector 120 and the traveling direction vector 124 is smaller than the threshold value. Since it is large, it is determined that the vehicle 12 does not exist between the second node 110b and the third node 110c in the route 112 (the vehicle 12 is not on the route 112). The path is also obtained when the angle θ1 formed by the first vector 120 and the traveling direction vector 124 is equal to or smaller than the threshold value and the angle θ2 formed by the traveling direction vector 124 and the second vector 122 is larger than the threshold value. 112, it is determined that the vehicle 12 does not exist between the second node 110b and the third node 110c (the vehicle 12 is not on the route 112).

  FIG. 10D shows a case where the angle θ1 formed by the first vector 120 and the traveling direction vector 124 is larger than the threshold value, but the length K of the first vector 120 is equal to or smaller than another threshold value. If the angle θ2 formed by the traveling direction vector 124 and the second vector 122 is equal to or smaller than the threshold value, it is determined that the vehicle 12 is on the route 112. If the angle θ2 formed by the traveling direction vector 124 and the second vector 122 is larger than the threshold value, but the length of the second vector 122 is equal to or smaller than another threshold value, the first vector 120 and If the angle θ1 formed with the traveling direction vector 124 is equal to or smaller than the threshold value, it is determined that the vehicle 12 is on the route 112. Returning to FIG. If the determination unit 86 determines that the vehicle 12 is on the route 112, the determination unit 86 outputs a packet signal including information corresponding to the route 112 to the notification unit 70.

  The operation of the communication system 100 configured as above will be described. FIG. 11 is a flowchart illustrating a procedure of reception processing by the terminal device 14. The deriving unit 84 derives the first vector 120, the second vector 122, and the traveling direction vector 124 (S10). The angle formed by the first vector 120 and the traveling direction vector 124 ≦ the threshold value (Y in S12), and the angle formed by the second vector 122 and the traveling direction vector 124 ≦ the threshold value (Y in S14). The determination unit 86 determines the processing of the packet signal (S16). The angle formed by the first vector 120 and the traveling direction vector 124 is not the threshold value (N in S12) or the angle formed by the second vector 122 and the traveling direction vector 124 is not the threshold value (N in S14). The determination unit 86 determines to discard the packet signal (S18).

  FIG. 12 is a flowchart showing another procedure of reception processing by the terminal device 14. This corresponds to a procedure in which the process of FIG. 10C is added to the flowchart of FIG. The deriving unit 84 derives the first vector 120, the second vector 122, and the traveling direction vector 124 (S50). The angle formed by the first vector 120 and the traveling direction vector 124 ≦ the threshold value (Y in S52), or the angle formed by the first vector 120 and the traveling direction vector 124 ≦ the threshold value (N in S52). ) If the length of the first vector 120 is equal to or less than another threshold (Y in S54), the determination unit 86 compares the angle formed by the second vector 122 and the traveling direction vector 124 with the threshold. Execute. The angle formed by the second vector 122 and the traveling direction vector 124 ≦ threshold (Y in S56), or the angle formed by the second vector 122 and the traveling direction vector 124 ≦ not the threshold (N in S56) ) If the length of the second vector 122 is equal to or smaller than another threshold (Y in S58), the determination unit 86 determines the processing of the packet signal (S60). When the length of the first vector 120 is not less than or equal to another threshold (N in S54), or when the length of the second vector 122 is not less than or equal to another threshold (N in S58), the determination unit 86 It is determined to discard the packet signal (S62).

  According to the embodiment of the present invention, since the first vector, the second vector, and the traveling direction vector derived from the position information of two adjacent nodes and the position information of the vehicle are used, the position of the own vehicle and the node is used. Identify relationships. Moreover, since the positional relationship between the host vehicle and the node is specified, the travel route along which the host vehicle is traveling can be specified. In addition, since the vector calculation is performed on the first vector, the second vector, and the traveling direction vector, the processing can be simplified. Moreover, since the packet signal from the base station apparatus installed on the road including the route is a processing target, it can be determined whether the host vehicle is traveling along the route. Further, when the host vehicle is traveling on a route, information on the route is processed, so that necessary information can be used. In addition, since necessary information is notified to the driver, the driver can be urged to drive safely.

(Example 2)
Next, a second embodiment of the present invention will be described. As in the first embodiment, the second embodiment also relates to a terminal device that performs a filtering process on a received packet signal. In the first embodiment, the packet signal from the base station apparatus is the target of the filtering process. In the second embodiment, the packet signal from the terminal apparatus mounted on the emergency vehicle is the target of the filtering process. The presence of an emergency vehicle can be ascertained with a siren, but its location and route are not known, and it may not be possible to immediately determine approach to the host vehicle. For example, a server is used to make an emergency vehicle approach determination. In the server, the approach determination of the emergency vehicle is performed based on information on a plurality of emergency vehicles and general vehicles, and there is a possibility that the processing time in the server becomes long. In addition, the emergency vehicle and the general vehicle always transmit information to the server and acquire an emergency vehicle approach determination result, so that a plurality of communications are required before the determination result is obtained. As a result, it is difficult to acquire the determination result in real time and notify the driver.

  In order to cope with this, the terminal device mounted on the emergency vehicle transmits a packet signal including position information and route information. Here, the route information is indicated by position information of a plurality of nodes, as in the first embodiment. When the terminal device mounted on the ordinary vehicle receives the packet signal, the terminal device determines whether or not the ordinary vehicle exists on the route of the emergency vehicle by executing the same processing as in the first embodiment. Therefore, since the driver of the general vehicle knows at an early stage that the emergency vehicle passes through the position of the own vehicle, the vehicle can be controlled smoothly. The communication system 100 according to the second embodiment is the same type as that in FIG. 1, the base station apparatus 10 according to the second embodiment is the same type as that in FIG. 2, and the terminal apparatus 14 according to the second embodiment is This is the same type as in FIG. 7, and here, the difference will be mainly described.

  FIGS. 13A to 13B show an outline of processing of the communication system 100 according to the second embodiment of the present invention. Here, two cases are assumed as cases where an emergency vehicle should be notified. FIG. 13A shows the on-route determination process. The route of the emergency vehicle is from the first node 110a to the seventh node 110g. Here, the first node 110a is a position where the emergency vehicle currently exists, and is indicated as Pe. The seventh node 110g is the destination of the route and is indicated as Pg. The partial path between adjacent nodes is indicated as “R”. For example, the partial path between the first node 110a and the second node 110b is indicated as “R1”. Moreover, the own vehicle (vehicle 12) exists in R4. That is, the host vehicle (vehicle 12) exists on the route of the emergency vehicle. At that time, the approach of the emergency vehicle is notified. In order to reduce the amount of data to be transmitted, a distance of the nearest several kilometers from the current location of the emergency vehicle is indicated. This is the range that emergency vehicles can reach in minutes.

  FIG. 13B shows route intersection determination processing. The route of the emergency vehicle is the same as that in FIG. In FIG. 13B, unlike FIG. 13A, the host vehicle (vehicle 12) does not exist on the route. However, the course of the host vehicle (vehicle 12) is expected to intersect the route. Even in such a case, the approach of the emergency vehicle is notified. The determination process in FIG. 13A is performed in the same manner as in the first embodiment, but the determination process in FIG. 13B is performed by a process different from that in the first embodiment. Details of this processing will be described later. Further, in FIGS. 13A to 13B, the support is terminated when the situation that does not satisfy the support condition continues for a certain period of time.

  Below, after demonstrating the structure of the terminal device 14 mounted in the emergency vehicle, the structure of the terminal device 14 mounted in the general vehicle is demonstrated. The emergency vehicle generation unit 66 sets a plurality of discrete nodes included in the route, as shown in FIGS. FIGS. 14A and 14B show an overview of node setting processing by the generation unit 66 according to the second embodiment of this invention. In FIG. 14A, Pe indicates the current position of the emergency vehicle, and Pg indicates the destination of the emergency vehicle. This route is set by, for example, a car navigation system mounted on an emergency vehicle. The generation unit 66 acquires the position information of the point N1 where the nearest right / left turn is made from the current position Pe of the emergency vehicle, and also acquires the distance L1 from Pe to N1. When the distance L1 is equal to or greater than the threshold value φ, the generation unit 66 generates the node M1 between Pe and N1 so that the inter-node distance is equal to or smaller than φ as shown in FIG. 14B. To do. In FIG. 14B, one node is generated between Pe and N1, but a plurality of nodes may be generated according to L1. Returning to FIG.

  The generation unit 66 acquires a point N2 where the next right / left turn is performed and a distance L2 from N1 to N2. When L2 is a distance greater than or equal to the threshold value φ, a node is generated between N1 and N2 so that the inter-node distance is equal to or less than φ. Here, since L2 is shorter than the threshold value φ, no node is generated. The generation unit 66 repeats the above processing until the number of nodes reaches the number of points that can be stored in the free area of inter-vehicle communication. When the number of generated nodes reaches a predetermined number, the generation unit 66 ends the node generation process.

  15A to 15C show packet signal formats defined in the terminal device 14 according to the second embodiment of the present invention. This corresponds to the format of the packet signal transmitted from the terminal device 14 mounted on the emergency vehicle. The emergency vehicle information is transmitted using inter-vehicle communication. FIG. 15A shows a format used in vehicle-to-vehicle communication. As shown in the figure, it is divided into a common area, a free area A, and a free area B. In addition, one or more free areas may be included. The common area includes vehicle position information that is current location information of the emergency vehicle. The vehicle position information is shown as shown in FIG. Returning to FIG.

  The free area A is an area used by the emergency vehicle passage assistance application. The type of emergency vehicle is registered in the vehicle type. The types of emergency vehicles are, for example, ambulances, fire engines, and police cars. The route information is shown as in FIG. This is included in an area of about 64 bytes out of 100 bytes. In the route information, the amount of data is reduced by using vectors. A route of about 1 km for which information is required is represented by about 6 points. Here, the position information of the node 110 closer to the position where the emergency vehicle is present among the plurality of nodes 110 discretely defined on the route is preferentially included. Note that by using a plurality of inter-vehicle communication packet signals, route information more than the number of points that can be transmitted with one inter-vehicle communication packet signal may be transmitted.

  Next, the configuration of the terminal device 14 mounted on a general vehicle will be described. FIG. 16 shows the configuration of the filtering unit 68 according to the second embodiment of the present invention. The filtering unit 68 includes a route determination unit 90 and a route intersection determination unit 92. The packet signal input to the filtering unit 68 is transmitted from another terminal device 14 mounted on the emergency vehicle. The on-path determination unit 90 performs the same process as the filtering unit 68 of FIG. 8, that is, the on-path determination process, on the input packet signal. That is, the on-route determination unit 90 determines whether the host vehicle (vehicle 12) exists on the route of the emergency vehicle by vector calculation.

FIGS. 17A to 17B show an outline of the process of the on-route determination unit 90. FIG. FIG. 17 (b) is the same as FIG. 13 (a), and FIG. 17 (a) is an enlarged view between the fourth node 110d and the fifth node 110e in FIG. 17 (b). . Position information Pa (latitude, longitude) of the host vehicle (vehicle 12) is input to the on-route determination unit 90. The on-route determination unit 90 derives the traveling direction vector v as follows. Here, the traveling direction vector v corresponds to the traveling direction vector 124.
v = Pa−Pa ′ (1)
Here, Pa indicates the current position, and Pa ′ indicates the position one second before. As described above, when the vehicle is stopped, the latest travel direction vector v in the past is used.

The on-route determination unit 90 also acquires emergency vehicle position information Pe (latitude, longitude) and emergency vehicle route information Ri. The on-route determination unit 90 confirms whether the following condition is satisfied.
c · Ri / (| c | * | Ri |) ≧ cos θ1 (2)
d · Ri / (| d | * | Ri |) ≧ cos θ1 (3)
Here, the vector d corresponds to the first vector 120, and the vector c corresponds to the second vector 122. The on-route determination unit 90 determines that the host vehicle (the vehicle 12) exists on the route when Expression (2) and Expression (3) are satisfied.

Further, the on-route determination unit 90 performs the traveling direction determination as follows.
X = v · Ri / (| v | * | Ri |) (4)
The on-route determination unit 90 determines that the emergency vehicle is approaching from behind the host vehicle (vehicle 12) if X ≧ cos θ2, and if X ≦ −cos θ2, the emergency vehicle is the host vehicle (vehicle 12). ), It is determined that the vehicle is approaching from the front of the vehicle 12, and if it is not the above, it is determined that there is an emergency vehicle around the vehicle 12. Thus, the traveling direction is determined by the vector to the point entering the route point that becomes the zero vector and the traveling direction vector v. The assistance when the traveling direction vector v is 0 is “an emergency vehicle is present in the vicinity”.

  The on-route determination unit 90 determines that the route is on the route when the vectors c and d are substantially zero vectors. Here, when | c | <ε or | d | <ε, a zero vector is assumed. The initial value is 15 m. When the emergency vehicle passes at the current position of the host vehicle (vehicle 12), the on-route determination unit 90 notifies whether the traveling direction is the same direction / opposite / left / right. Further, the on-route determination unit 90 determines the approach direction such as any one of front, rear, and surrounding. Returning to FIG.

  The route intersection determination unit 92 determines whether the route of the emergency vehicle and the host vehicle (vehicle 12) intersects by vector calculation. 18A to 18C show an outline of processing of the route intersection determination unit 92. FIG. FIG. 18 (b) is the same as FIG. 13 (b), and FIG. 18 (a) is an enlarged view between the fourth node 110d and the fifth node 110e in FIG. 18 (b). . The route intersection determination unit 92 calculates an intersection based on the route information and the traveling direction vector v. Assuming that the speed of the emergency vehicle is 20 km / h, the time until the emergency vehicle reaches the intersection is t. This is because the target of the vehicle receiving assistance increases when the speed of the emergency vehicle is slower, so that the determination criterion is the safe side. The route intersection determination unit 92 does not support when t is greater than or equal to the threshold Et, and supports when the host vehicle (vehicle 12) reaches the intersection within time t.

  The route intersection determination unit 92 notifies when the emergency vehicle crosses the course of the host vehicle (vehicle 12). An example of the notification is “emergency vehicle is approaching. The route intersection determination unit 92 assists when the host vehicle (vehicle 12) reaches the intersection before the emergency vehicle reaches the intersection of the course. The siren will be heard from behind even after passing the intersection. As a result, the driver makes a decision such as avoidance behavior at that time, so it is meaningful to tell in advance. The route intersection determination unit 92 does not support when the time until the emergency vehicle reaches the intersection is t seconds or more.

  Next, the process in the route intersection determination unit 92 will be described in more detail. FIG. 18C shows the process of the route intersection determination unit 92. As a premise, Cross (v1, v2) indicates the outer product of the vector v1 and the vector v2, Pa is the position of the own vehicle (vehicle 12), and Va is the traveling direction vector v of the own vehicle (vehicle 12). (Latitude and longitude speed), Ri is a route vector of the emergency vehicle, r is a vector from the position Pa of the own vehicle (vehicle 12) to the starting point of the route Ri, and X is This is the position where the course of the vehicle (vehicle 12) and the emergency vehicle intersect.

The route intersection determination unit 92 performs a collision determination by the following calculation.
Cross (Va, Ri) ≧ sin θ (5)
Ta = Cross (r, Ri) / Cross (Va, Ri) (6)
Tb = Cross (r, Va) / Cross (Va, Ri) (7)
The route intersection determination unit 92 determines that the route intersects when 0 ≦ Tb ≦ 1 and Ta ≧ 0. The route intersection determination unit 92 uses the latest traveling direction vector v when the speed of the host vehicle (vehicle 12) is zero.

The route intersection determination unit 92 indicates that when Cross (Va, Ri) = 0, the route of the host vehicle (vehicle 12) and the route of the emergency vehicle are traveling in the same direction or in the opposite direction. Since it is determined that it is not on the route, it is not included in the support target. The route intersection determination unit 92 calculates the predicted collision position X as follows.
X = Pa (t) + Ta * Va (t) (8)

  FIG. 19 shows an image displayed on the notification unit 70 according to the second embodiment of the present invention. The notification unit 70 notifies the approach of the emergency vehicle by a map screen or voice / sound effect. In addition, the notification unit 70 displays the route of the emergency vehicle with an arrow and displays the position of the emergency vehicle with an icon. Furthermore, the notification unit 70 changes the display method when the emergency vehicle is approaching the host vehicle (vehicle 12) and when the emergency vehicle does not affect the host vehicle (vehicle 12).

  FIG. 20 is a flowchart illustrating a procedure of reception processing by the terminal device 14 according to the second embodiment of this invention. The filtering unit 68 receives a packet signal from the emergency vehicle (S30). If present on the path (Y in S32), the on-path determination unit 90 determines the processing of the packet signal (S36). If the route does not exist (N in S32) and the routes intersect (Y in S34), the route intersection determination unit 92 determines the processing of the packet signal (S36). If the routes do not intersect (N in S34), the on-route determination unit 90 or the route intersection determination unit 92 determines to discard the packet signal (S38).

  According to the embodiment of the present invention, since the packet signal from the terminal device mounted on the emergency vehicle is the target of processing, it can be determined whether the host vehicle is traveling along the route of the emergency vehicle. In addition, since the location information of some nodes is included, the amount of data can be reduced. In addition, since the data amount is reduced, the position information can be stored in the packet signal even when the data capacity of the packet signal used for inter-vehicle communication is small. In addition, since the general vehicle determines the approach of the emergency vehicle, the travel route of the emergency vehicle can be notified to the driver in real time. In addition, since the travel route of the emergency vehicle is notified to the driver in real time, it is possible to safely avoid the emergency vehicle, such as smoothly stopping the emergency vehicle before it approaches the host vehicle.

  In the above, this invention was demonstrated based on the Example. This embodiment is an exemplification, and it will be understood by those skilled in the art that various modifications can be made to each of those constituent elements or combinations of processing processes, and such modifications are also within the scope of the present invention. .

  The outline of one embodiment of the present invention is as follows. A wireless device according to an aspect of the present invention is a wireless device that can be mounted on a vehicle, is a packet signal from another wireless device, and has position information of a plurality of nodes discretely defined on a route. A reception unit that receives the included packet signal, and position information of the first node of the plurality of nodes and position information of the second node that is the next node after the first node from the packet signal received by the reception unit And (1) the position information of the first node extracted by the extraction unit to the position information acquired by the acquisition unit. First vector heading, (2) Second vector heading from position information acquired by the acquisition unit to position information of the second node extracted by the extraction unit, (3) Change in position information acquired by the acquisition unit The derivation unit for deriving the traveling direction vector, the angle formed by the first vector derived by the derivation unit and the traveling direction vector is equal to or less than a threshold value, and the second vector derived by the derivation unit and the traveling direction vector And a determination unit that determines that the vehicle is on the route when the angle is equal to or smaller than the threshold value.

  According to this aspect, since the vector derived from the position information of two adjacent nodes and the position information of the vehicle is used, the travel route on which the host vehicle is traveling can be specified.

  Another wireless device that is a transmission source of the packet signal received by the reception unit may be installed on a road including the route. In this case, since a packet signal from another wireless device installed on the road including the route is a processing target, it can be determined whether the host vehicle is traveling along the route.

  Another wireless device that is a transmission source of the packet signal received by the reception unit may be mounted on another vehicle. In this case, since a packet signal from another wireless device mounted on another vehicle is a processing target, it is possible to determine whether the host vehicle is traveling along the route of another vehicle.

  The packet signal received by the receiving unit is a part of a plurality of nodes that are discretely defined on the route and is closer to the position where another vehicle is present. Node position information may be included. In this case, since the position information of some nodes is included, the amount of data can be reduced.

  10 base station device, 12 vehicle, 14 terminal device, 20 antenna, 22 RF unit, 24 modulation / demodulation unit, 26 processing unit, 28 control unit, 30 network communication unit, 32 frame definition unit, 34 selection unit, 36 generation unit, 50 Antenna, 52 RF unit, 54 modulation / demodulation unit, 56 processing unit, 58 control unit, 60 timing identification unit, 62 transfer determination unit, 64 position information acquisition unit, 66 generation unit, 68 filtering unit, 70 notification unit, 72 extraction unit, 74 carrier sense unit, 80 input unit, 82 position information extraction unit, 84 derivation unit, 86 determination unit, 100 communication system.

Claims (4)

A wireless device that can be mounted on a vehicle,
A receiving unit that receives a packet signal from another wireless device and includes position information of a plurality of nodes discretely defined on a path;
An extraction unit that extracts position information of a first node of a plurality of nodes and position information of a second node that is a node next to the first node from a packet signal received by the reception unit;
An acquisition unit for acquiring position information of a vehicle on which the wireless device is mounted;
(1) From the position information of the first node extracted in the extraction unit, a first vector that goes to the position information acquired in the acquisition unit, (2) Extracted in the extraction unit from the position information acquired in the acquisition unit A second vector toward the position information of the second node; (3) a derivation unit that derives a traveling direction vector that is a change in the position information acquired in the acquisition unit;
The angle formed between the first vector derived in the derivation unit and the traveling direction vector is less than or equal to the threshold value, and the angle formed between the second vector derived in the derivation unit and the traveling direction vector is equal to or less than the threshold value. A determination unit that determines that the vehicle is on the route, and
A wireless device comprising:   The wireless device according to claim 1, wherein another wireless device that is a transmission source of the packet signal received by the receiving unit is installed on a road including a route.   The wireless device according to claim 1, wherein another wireless device that is a transmission source of the packet signal received by the receiving unit is mounted on another vehicle.   The packet signal received by the receiving unit is a part of a plurality of nodes discretely defined on the route and closer to the position where another vehicle exists. The wireless device according to claim 3, further comprising position information of a node.

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