JP5814563B2 - Terminal apparatus and base station apparatus - Google Patents

Description

  The present invention relates to a communication technique, and more particularly, to a terminal device and a base station device that broadcast a signal including predetermined information.

  Road-to-vehicle communication is being studied to prevent collisions at intersections. In the road-to-vehicle communication, information on the situation of the intersection is communicated between the roadside device and the vehicle-mounted device. Road-to-vehicle communication requires the installation of roadside equipment, which increases labor and cost. On the other hand, if it is the form which communicates information between vehicle-to-vehicle communication, ie, onboard equipment, installation of a roadside machine will become unnecessary. In that case, for example, the current position information is detected in real time by GPS (Global Positioning System), etc., and the position information is exchanged between the vehicle-mounted devices so that the own vehicle and the other vehicle enter the intersection respectively. (See, for example, Patent Document 1).

JP 2005-202913 A

  In a wireless LAN (Local Area Network) compliant with a standard such as IEEE 802.11, an access control function called CSMA / CA (Carrier Sense Multiple Access Collision Aviation) is used. Therefore, in the wireless LAN, the same wireless channel is shared by a plurality of terminal devices. In such CSMA / CA, a packet signal is transmitted after confirming that no other packet signal is transmitted by carrier sense. When applying a wireless LAN to inter-vehicle communication such as ITS (Intelligent Transport Systems), it is necessary to transmit information to terminal devices mounted on each of an unspecified number of vehicles. It is desirable that As a result, the terminal device detects the approach of another vehicle by receiving the broadcast signal, and notifies the driver of the approach by notifying the driver of the approach to the driver. To arouse.

  In addition to preventing collision accidents between vehicles, it is also desirable to prevent collision accidents between pedestrians and the like and vehicles. In order to cope with this, the terminal device is carried by a pedestrian in addition to being mounted on the vehicle. In order to prevent the pedestrian from colliding with the vehicle, the terminal device carried by the pedestrian notifies the in-vehicle terminal device of the existing position. On the other hand, since a terminal device carried by a pedestrian is driven by a battery, the amount of processing is required to be reduced as compared with an in-vehicle terminal device. For example, the approach of another vehicle is not notified to the pedestrian. It is desirable that the communication function of the terminal device carried by such a pedestrian is stopped in a certain area. For example, in facilities such as schools and in transportation such as trains. In consideration of the convenience of pedestrians, it is desirable that the communication function is automatically stopped or resumed.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a technique for automatically stopping a communication function in a certain area.

In order to solve the above-described problems, a terminal device according to an aspect of the present invention is a terminal device that can be carried by a pedestrian, and the position of the terminal device is determined in order to communicate with the vehicle-mounted device or roadside device A first communication unit that performs a first wireless communication that broadcast-transmits a packet signal that stores therein information, and a second communication that communicates information using a second wireless communication in which a communicable area is narrower than the first wireless communication. And a control unit that controls the operation of the first communication unit and the operation of the second communication unit. The second communication unit is configured to be able to communicate with the external communication device installed in a predetermined area that does not require the first wireless communication by the second wireless communication, and the terminal device is in the area. In the case of entering and in the case of leaving the area, communication is performed with the external communication device by the second wireless communication, and when the control unit enters the area, the second communication unit Until the second communication unit communicates when leaving the area after the communication , the broadcast transmission of the packet signal by the first communication unit is stopped.

  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, the communication function can be automatically stopped in a certain area.

It is a figure which shows the structure of the communication system which concerns on the Example of this invention. It is a figure which shows the structure of the base station apparatus of FIG. FIGS. 3A to 3D are diagrams showing frame formats defined in the communication system of FIG. FIGS. 4A to 4B are diagrams illustrating the configuration of the subframes of FIGS. 3A to 3D. FIGS. 5A and 5B are diagrams showing a format of a MAC frame stored in a packet signal defined in the communication system of FIG. It is a figure which shows the structure of the terminal device carried by the pedestrian of FIG. It is a sequence diagram which shows the communication procedure in the communication system of FIG. It is a sequence diagram which shows another communication procedure in the communication system of FIG. It is a figure which shows the structure of the communication system which concerns on the modification of this invention. It is a figure which shows the structure of the communication system which concerns on another modification of this invention. It is a figure which shows the structure of the terminal device of FIG. It is a sequence diagram which shows the communication procedure in the communication system of FIG. It is a sequence diagram which shows another communication procedure in the communication system of FIG. It is a flowchart which shows the setting procedure of the terminal device which concerns on another modification of this invention.

  Before describing the present invention in detail, an outline will be described. Embodiments of the present invention relate to a communication system that performs 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. As inter-vehicle communication, the terminal device broadcasts and transmits a packet signal storing information such as the speed and position of the vehicle (hereinafter referred to as “data”). Further, the other terminal device receives the packet signal and recognizes the approach of the vehicle based on the data. The driver is alerted by notifying the driver of the approach of the vehicle. In order to reduce interference between vehicle-to-vehicle communication and road-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 transmits a packet signal in a period other than the road and vehicle transmission period. Thus, since the road-to-vehicle communication and the vehicle-to-vehicle communication are time-division multiplexed, the collision probability of packet signals between them is reduced. The inter-vehicle communication is performed by the CSMA method in a period for performing inter-vehicle communication other than the road-vehicle transmission period (hereinafter referred to as “vehicle transmission period”). Such a terminal device is also carried by a pedestrian. A terminal device carried by a pedestrian is battery-driven and requires low power consumption. Therefore, the terminal device carried by the pedestrian only broadcasts a packet signal storing data, and does not notify the pedestrian of the approach of the vehicle. In order to accurately detect whether or not a pedestrian carrying such a terminal device enters a pedestrian crossing and to notify the pedestrian, the communication system according to the present embodiment executes the following processing. In the following, even terminal devices carried by pedestrians are referred to as inter-vehicle communication and road-to-vehicle communication.

  Near-end wireless communication readers / writers are installed at both ends of the pedestrian crossing. The terminal device also has a short-range wireless communication function. When a pedestrian approaches a reader / writer so as to enter a pedestrian crossing, the terminal device transmits information to the reader / writer by short-range wireless communication. The information is the ID of the terminal device or pedestrian information. The reader / writer is connected to the base station apparatus and outputs the received information to the base station apparatus. When the base station apparatus inputs information, the base station apparatus determines a change schedule of each lighting color of the traffic light. For example, when the traffic light on the pedestrian side is red for a certain period or longer, the base station apparatus determines a change schedule so as to change this to blue early and change the signal on the roadway side to red. The base station apparatus notifies the packet signal including the change schedule through road-to-vehicle communication. Since the vehicle-mounted terminal device that has received the packet signal notifies the driver that the color of the traffic light changes to red, it can notify the driver that the pedestrian enters the pedestrian crossing. In addition, after transmitting information to the reader / writer, the terminal device stops reporting the packet signal for a certain period. Thereby, power consumption is reduced.

  FIG. 1 shows a configuration of a communication system 100 according to an embodiment 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. , An eighth vehicle 12h, a traffic light 16, a first reader / writer 18a, a second reader / writer 18b, which are collectively referred to as a reader / writer 18, and a network 202. Each vehicle 12 is equipped with a terminal device (not shown). The area 212 is formed around the base station apparatus 10, and the 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.

  A traffic light 16 is installed at the intersection. Actually, a traffic light 16 is installed in each direction of the road that intersects at the intersection, but only one traffic light 16 is shown here for the sake of clarity. A base station device 10 is also installed at the intersection. The base station device 10 controls communication between terminal devices. The base station device 10 repeatedly generates a frame including a plurality of subframes based on a signal received from a GPS satellite (not shown) and a frame formed by another base station device 10 (not shown). 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 the plurality of subframes. 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.

  The base station apparatus 10 is installed in the vicinity of the traffic light 16 and is connected to the first reader / writer 18a, the second reader / writer 18b, and the traffic light 16. The reader / writer 18 performs short-range wireless communication with a terminal device (not shown). Here, the terminal device capable of communicating with the reader / writer 18 is not a terminal device mounted on the vehicle 12 but a terminal device carried by a pedestrian. The short-range wireless communication is, for example, NFC (Near Field Communication), which is communication having a narrower communication area than the above-described road-to-vehicle communication or vehicle-to-vehicle communication. When the pedestrian enters the pedestrian crossing, he holds the terminal device over the reader / writer 18. Here, the reader / writer 18 is assumed to be the first reader / writer 18a. The first reader / writer 18a communicates with the terminal device, and outputs information related to the terminal device acquired by communication to the base station device 10.

  The base station apparatus 10 recognizes that a pedestrian is about to enter a pedestrian crossing by receiving information from the first reader / writer 18a. The base station apparatus 10 determines a schedule for lighting each lighting color in the traffic light 16 based on the received information. This schedule corresponds to the aforementioned change schedule. For example, the lighting schedule on the roadway side is currently blue, and the change schedule is determined so that the change from blue to red is accelerated. Such a change schedule makes it possible to notify that a pedestrian is about to cross a pedestrian crossing. The base station apparatus 10 notifies the change schedule by including it in the packet signal. Data different from the change schedule can be stored in the packet signal. One is control information and the other is traffic jam information.

  Further, when the pedestrian finishes crossing the pedestrian crossing and enters the pedestrian crossing, the portable terminal is held over a reader / writer 18 different from the reader / writer 18 holding the terminal device, for example, the second reader / writer 18b. The second reader / writer 18b communicates with the terminal device, and outputs information related to the terminal device acquired by communication to the base station device 10. The base station device 10 recognizes that the pedestrian is leaving the pedestrian crossing by receiving information from the second reader / writer 18b. Based on the received information, the base station apparatus 10 again determines a schedule for lighting each lighting color in the traffic light 16. The base station apparatus 10 broadcasts a packet signal in which a new change schedule is stored.

  The vehicle 12 is driven by an engine and is equipped with a terminal device. The terminal device generates a frame based on the control information included in the received packet signal. As a result, the frame generated in each of the plurality of terminal devices is synchronized with the frame generated in the base station device 10. Moreover, a terminal device alert | reports a packet signal by performing CSMA / CA in a vehicle transmission period. For example, the terminal device stores information on the location in the packet signal. The terminal device also stores control information in the packet signal. That is, the control information transmitted from the base station device 10 is transferred by the terminal device. On the other hand, a terminal device that cannot receive a packet signal from the base station device 10, that is, a terminal device existing outside the area 214 broadcasts the packet signal by executing CSMA / CA regardless of the frame configuration.

  Furthermore, the terminal device notifies the driver of the approach of the vehicle on which the other terminal device is mounted by receiving a packet signal from the other terminal device. The terminal device also acquires a change schedule included in the packet signal from the base station device 10 and notifies the driver of a change in the lighting color of the traffic light 16. The driver knows that the pedestrian can cross the pedestrian crossing by recognizing the change in the lighting color to red. As described above, the terminal device is also carried by a pedestrian. Such a terminal device is different from the terminal device mounted on the vehicle 12 in the following points. One is that it has a short-range wireless communication function, and the other is that it does not have a function for notifying the contents of a received packet signal.

  FIG. 2 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 30, and a network communication unit 36. The processing unit 26 includes an acquisition unit 32, a re-acquisition unit 34, a determination unit 38, a traffic signal IF unit 48, a frame definition unit 40, a selection unit 42, and a generation unit 46.

  The RF unit 22 receives a packet signal from a terminal device (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 40 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 40 generates a plurality of frames based on the time information. For example, the frame defining unit 40 generates 10 frames of “100 msec” by dividing the period of “1 sec” into 10 on the basis of the timing indicated by the time information. By repeating such processing, the frame is defined to be repeated. Note that the frame defining unit 40 may detect the 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. 3A to 3D show frame formats defined in the communication system 100. FIG. FIG. 3A shows the structure of the frame. The frame is formed of N subframes indicated as the first subframe to the Nth subframe. For example, when the frame length is 100 msec and N is 8, a subframe having a length of 12.5 msec is defined. The description of FIGS. 3B to 3D will be described later and returns to FIG.

  The selection part 42 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 42 receives a frame defined by the frame defining unit 40. The selection unit 42 inputs a demodulation result from another base station device 10 or a terminal device (not shown) via the RF unit 22 and the modem unit 24. The selection unit 42 extracts a demodulation result from another base station apparatus 10 from the input demodulation results. The selection unit 42 identifies 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 42 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 42 acquires reception power corresponding to the demodulation result, and gives priority to subframes with low reception power. Select

  FIG. 3B 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 can notify the packet signal. That is, in the road and vehicle transmission period which is the head period of the first subframe, the first base station apparatus 10a can notify the packet signal, and in the frame, the terminal apparatus transmits in the vehicle and vehicle transmission period other than the road and vehicle transmission period. It is defined that the packet signal can be broadcast. Furthermore, the first base station apparatus 10a sets only the vehicle transmission period from the second subframe to the Nth subframe.

  FIG. 3C shows a configuration of a frame generated by the second 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. 3D 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 42 outputs the selected subframe number to the generation unit 46.

  The generation unit 46 sets a road and vehicle transmission period in the subframe of the subframe number received from the selection unit 42, and generates an RSU packet signal to be notified during the road and vehicle transmission period. In the following description, the RSU packet signal and the packet signal are used without distinction. FIGS. 4A to 4B show subframe configurations. FIG. 4A shows a subframe in which a road and vehicle transmission period is set. As illustrated, one subframe is configured in the order of a road and vehicle transmission period and a vehicle and vehicle transmission period. FIG. 4B shows the arrangement of packet signals during the road and vehicle transmission period. As illustrated, a plurality of RSU packet signals are arranged in the road and vehicle transmission period. Here, the front and rear packet signals are separated by SIFS (Short Interframe Space).

  Here, the configuration of the RSU packet signal will be described. FIGS. 5A and 5B show the formats of MAC frames stored in packet signals defined in the communication system 100. FIG. FIG. 5A shows the format of the MAC frame. In the MAC frame, “MAC header”, “LLC header”, “message header”, “data payload”, and “FCS” are arranged in order from the top. Information included in the data payload will be described later. FIG. 5B is a diagram illustrating a configuration of a message header generated by the generation unit 46. The message header includes a basic part.

  The basic part includes “protocol version”, “transmission node type”, “number of reuses”, “TSF timer”, and “RSU transmission period length”. The protocol version indicates the version of the corresponding protocol. The transmission node type indicates the transmission source of the packet signal including the MAC frame. For example, “0” indicates a terminal device, and “1” indicates the base station device 10. When the selection unit 42 extracts a demodulation result from another base station apparatus 10 from among the input demodulation results, the selection unit 42 uses the value of the transmission node type. The reuse count indicates an index of validity when the message header is transferred by the terminal device, and the TSF timer indicates the transmission time. The RSU transmission period length indicates the length of the road and vehicle transmission period, and can be said to be information relating to the road and vehicle transmission period. Returning to FIG.

  The network communication unit 36 is connected to a network 202 (not shown). The network communication unit 36 receives traffic jam information from the network 202. The generation unit 46 acquires the traffic jam information from the network communication unit 36 and stores it in the data payload, thereby generating the RSU packet signal described above.

  The acquisition unit 32 is connected to a reader / writer 18 (not shown). As described above, the reader / writer 18 communicates with a terminal device carried by a pedestrian by short-range wireless communication. The acquisition unit 32 acquires information related to the terminal device from the terminal device having a short-range wireless communication function via the reader / writer 18. An example of the information regarding the terminal device is the ID of the terminal device or pedestrian information, and the pedestrian information includes information that can specify the age of the pedestrian, such as the date of birth. The acquisition unit 32 outputs the acquired information to the determination unit 38 and the re-acquisition unit 34.

  The traffic signal IF unit 48 is connected to the traffic signal 16 (not shown). Here, a plurality of traffic lights 16 may be provided. The traffic light IF unit 48 receives a schedule for lighting each lighting color from the traffic light 16. This is the above-described change schedule, and the traffic light 16 is lit while changing the lighting color in accordance with the change schedule. For example, the change schedule shows the correspondence between the time and the lighting color. When a plurality of traffic lights 16 are installed at one intersection, their change schedules correspond to each other.

  For example, when the lighting color of the traffic light 16 for one roadway is blue, the lighting color of the traffic light 16 for the roadway intersecting with this is red. Therefore, the schedule for a plurality of traffic lights 16 installed at one intersection may be collected in the change schedule. Further, the change schedule may include a schedule for a plurality of traffic lights 16 to be operated in conjunction with each other, not limited to one intersection. When the traffic signal IF unit 48 receives a change schedule from the determination unit 38 described later, the traffic signal IF unit 48 outputs the change schedule to each traffic signal 16. This corresponds to instructing each traffic light 16 to perform an operation according to the change schedule.

  The determination unit 38 receives the change schedule from the traffic signal IF unit 48 and also receives information related to the terminal device from the acquisition unit 32. The determination unit 38 determines a new change schedule based on the information acquired by the acquisition unit 32 so as to change the accepted change schedule. For example, a new change schedule is determined so as to extend the red lighting period of the traffic light 16 for the roadway where the pedestrian crosses the pedestrian crossing scheduled to cross. In that case, the determination part 38 may determine a change schedule so that the lighting interval by each lighting color of a traffic light may change according to the content of the acquired information. For example, if the age of the pedestrian is older than 70, the red lighting period of the traffic light 16 for the roadway that the pedestrian crosses the pedestrian crossing scheduled to cross is further increased. The determination unit 38 outputs the determined change schedule to the traffic signal IF unit 48 and also outputs it to the generation unit 46.

  The generation unit 46 receives the change schedule from the determination unit 38 and stores the change schedule in the data payload, thereby generating the RSU packet signal described above. Since such a packet signal is notified from the modem unit 24 and the RF unit 22, the driver is informed of the presence of a pedestrian according to the change schedule. Similar to the acquisition unit 32, the reacquisition unit 34 is connected to a reader / writer 18 (not shown). The reacquisition unit 34 receives information related to the terminal device from the acquisition unit 32. The reacquisition unit 34 outputs the information to the determination unit 38 when the information about the terminal device 14 is reacquired from the same terminal device 14 within a certain period after the acquisition unit 32 acquires the information. . Here, the reader / writer 18 from which the acquisition unit 32 receives information and the reader / writer 18 from which the re-acquisition unit 34 receives information are different from each other. For example, when the acquisition unit 32 receives information from the first reader / writer 18a, the re-acquisition unit 34 receives information from the second reader / writer 18b.

  The determination unit 38 receives the change schedule from the traffic signal IF unit 48 and also receives information related to the terminal device from the reacquisition unit 34. By receiving information about the same terminal device from the acquisition unit 32 and the re-acquisition unit 34, the determination unit 38 recognizes that the pedestrian has crossed the pedestrian crossing. Based on the information reacquired by the reacquisition unit 34, the determination unit 38 re-determines the lighting color change schedule of the traffic light 16. For example, a new change schedule is re-determined so as to shorten the red lighting period of the traffic light 16 for the roadway where the pedestrian crosses the pedestrian crossing scheduled to cross.

  If the determination unit 38 does not receive information from the re-acquisition unit 34 after a certain period of time has passed after receiving information about the terminal device from the acquisition unit 32, the determination unit 38 determines the lighting color of the traffic light 16. The change schedule may be redetermined. This is when the terminal device is held over the first reader / writer 18a when the pedestrian enters the pedestrian crossing, but the terminal device is not held over the second reader / writer 18b when the pedestrian leaves the pedestrian crossing. Equivalent to. The determination unit 38 outputs the determined change schedule to the traffic signal IF unit 48 and also outputs it to the generation unit 46. The generation unit 46 receives the re-decided change schedule from the determination unit 38 and stores it in the data payload, thereby generating the RSU packet signal described above. Since such a packet signal is notified from the modem unit 24 and the RF unit 22, the driver is notified of the end of the pedestrian crossing according to the change schedule. The control unit 30 controls processing of the entire base station apparatus 10.

  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 by hardware only, software only, or a combination thereof.

  FIG. 6 shows a configuration of the terminal device 14 carried by a pedestrian. The terminal device 14 includes a first wireless communication unit 80, a second wireless communication unit 82, and a control unit 84. The first wireless communication unit 80 includes an antenna 50, an RF unit 52, a modem unit 54, and a processing unit 56. The processing unit 56 includes a generation unit 64, a timing identification unit 60, a transfer determination unit 70, and an acquisition unit 72. The timing specifying unit 60 includes an extraction unit 66 and a carrier sense unit 68. The antenna 50, the RF unit 52, and the modem unit 54 execute the same processing as the antenna 20, the RF unit 22, and the modem unit 24 in FIG. Therefore, here, the difference will be mainly described.

  The second wireless communication unit 82 performs short-range wireless communication. Short-range wireless communication is communication in which the communicable area is narrower than vehicle-to-vehicle communication or road-to-vehicle communication, and a known technique may be used for this, and thus description thereof is omitted here. The second wireless communication unit 82 holds information related to the terminal device 14 described above, and transmits information related to the terminal device 14 to the reader / writer 18 (not shown) when short-range wireless communication is executed. The second wireless communication unit 82 performs communication between the reader / writer 18 (not shown) when a pedestrian enters the pedestrian crossing. Further, the second wireless communication unit 82 may execute communication between the reader / writer 18 (not shown) even when the pedestrian leaves the pedestrian crossing. The second wireless communication unit 82 outputs to the control unit 84 that the communication has been performed when the pedestrian enters the pedestrian crossing and that the communication has been performed when the pedestrian has left the pedestrian crossing.

  The modem unit 54 and the processing unit 56 receive packet signals from other terminal devices 14 and the base station device 10 (not shown). As described above, the modem unit 54 and the processing unit 56 receive the packet signal from the base station apparatus 10 during the road and vehicle transmission period. As described above, the modem unit 54 and the processing unit 56 receive packet signals from other terminal devices 14 during the vehicle transmission period. Note that the modem unit 54 and the processing unit 56 may stop reception during the vehicle transmission period in order to achieve low power consumption.

  When the demodulation result from the modem unit 54 is a packet signal from the base station apparatus 10 (not shown), the extraction unit 66 specifies the timing of the subframe in which the road-vehicle transmission period is arranged. At that time, the extraction unit 66 estimates that it exists in the area 212 of FIG. The extraction unit 66 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 RSU transmission period length. Note that the generation of the frame only needs to be performed in the same manner as the frame defining unit 40 described above, and the description thereof is omitted here. As a result, the extraction unit 66 generates a frame synchronized with the frame formed in the base station apparatus 10.

  On the other hand, when the extraction unit 66 has not received the RSU packet signal, the extraction unit 66 estimates that the extraction unit 66 exists outside the area 214 in FIG. When it is estimated that the extraction unit 66 exists in the area 212, the extraction unit 66 selects the vehicle transmission period. When it is estimated that the extraction unit 66 exists outside the area 214, the extraction unit 66 selects a timing unrelated to the frame configuration. When the vehicle transmission period is selected, the extraction unit 66 outputs information on the frame and subframe timing and the vehicle transmission period to the carrier sense unit 68. When selecting the timing unrelated to the frame configuration, the extraction unit 66 instructs the carrier sense unit 68 to execute carrier sense.

  The carrier sense unit 68 receives information regarding the timing of the frames and subframes and the vehicle transmission period from the extraction unit 66. The carrier sense unit 68 measures the interference power by performing carrier sense during the vehicle transmission period. Moreover, the carrier sense part 68 determines the transmission timing in a vehicle transmission period based on interference power. More specifically, the carrier sense unit 68 stores a predetermined threshold value in advance, and compares the interference power with the threshold value. If the interference power is smaller than the threshold value, the carrier sense unit 68 determines the transmission timing. When receiving the carrier sense execution instruction from the extraction unit 66, the carrier sense unit 68 determines the transmission timing by executing the CSMA without considering the frame configuration. The carrier sense unit 68 notifies the generation unit 64 of the determined transmission timing.

  The acquisition unit 72 includes a GPS receiver, a gyro sensor, a vehicle speed sensor, and the like (not shown), and based on data supplied from the GPS receiver, the presence position, the traveling direction, the moving speed, and the like (hereinafter referred to as “position information”). Are collectively called). 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 acquisition unit 72 outputs the position information to the generation unit 64.

  The transfer determination unit 70 controls the transfer of the message header. The transfer determining unit 70 extracts a message header from the packet signal. When the packet signal is directly transmitted from the base station apparatus 10, the reuse count is set to “0”. However, when the packet signal is transmitted from another terminal apparatus 14, the reuse is performed. The number of times is set to a value of “1 or more”. The transfer determination unit 70 selects a message header to be transferred from the extracted message header. Here, for example, the message header with the smallest number of reuses is selected. In addition, the transfer determination unit 70 may generate a new message header by combining the contents included in the plurality of message headers. The transfer determination unit 70 outputs the message header to be selected to the generation unit 64. At that time, the transfer determination unit 70 increases the number of reuses by “1”.

  The generation unit 64 receives position information from the acquisition unit 72 and receives a message header from the transfer determination unit 70. The generation unit 64 stores the position information in the data payload using the MAC frame shown in FIGS. The generation unit 64 generates a packet signal including a MAC frame, 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 68. Send. This corresponds to inter-vehicle communication. The transmission timing is included in the vehicle transmission period.

  The control unit 84 controls the operation of the first wireless communication unit 80 and the operation of the second wireless communication unit 82. The control unit 84 normally operates the first wireless communication unit 80. The control unit 84 stops the operation of the first wireless communication unit 80 until a predetermined period elapses after the communication by the second wireless communication unit 82 ends. Specifically, the control unit 84 operates the first wireless communication unit 80 until a predetermined period elapses after the second wireless communication unit 82 communicates when entering the pedestrian crossing. Stop. This is equivalent to stopping the inter-vehicle communication while the pedestrian crosses the pedestrian crossing. The predetermined period is a period required for the pedestrian to cross the pedestrian crossing. When the second wireless communication unit 82 communicates when leaving the pedestrian crossing, the control unit 84 resumes the operation of the first wireless communication unit 80 even if a predetermined period has not elapsed. This is equivalent to restarting inter-vehicle communication when a pedestrian has crossed a pedestrian crossing.

  Note that the terminal device 14 mounted on the vehicle 12 does not include the second wireless communication unit 82 and the control unit 84. Instead, the terminal device 14 mounted on the vehicle 12 includes a notification unit. The notification unit acquires a packet signal from the base station device 10 (not shown) during the road-vehicle transmission period, and acquires a packet signal from another terminal device 14 (not shown) during the vehicle-vehicle transmission period. As a process for the acquired packet signal, the notification unit notifies the driver of the approach of another vehicle 12 (not shown) or the like via a monitor or a speaker according to the content of the data stored in the packet signal.

  The operation of the communication system 100 configured as above will be described. FIG. 7 is a sequence diagram showing a communication procedure in the communication system 100. This corresponds to a case where the pedestrian does not hold the terminal device 14 over the reader / writer 18 when leaving the pedestrian crossing. The terminal device 14 broadcasts the packet signal, and the base station device 10 receives the packet signal (S10). When the pedestrian holds the terminal device 14 over the first reader / writer 18a to cross the pedestrian crossing, the terminal device 14 communicates with the first reader / writer 18a (S12). The first reader / writer 18a notifies the base station apparatus 10 of information acquired by communication (S14). The terminal device 14 stops road-to-vehicle communication and vehicle-to-vehicle communication (S16). The base station apparatus 10 determines the change schedule (S18) and broadcasts the packet signal storing the change schedule (S20). The terminal device 14 recognizes that a certain period has elapsed since the communication with the first reader / writer 18a (S22). The terminal device 14 broadcasts the packet signal, and the base station device 10 receives the packet signal (S24).

  FIG. 8 is a sequence diagram illustrating another communication procedure in the communication system 100. The terminal device 14 broadcasts the packet signal, and the base station device 10 receives the packet signal (S50). When the pedestrian holds the terminal device 14 over the first reader / writer 18a to cross the pedestrian crossing, the terminal device 14 communicates with the first reader / writer 18a (S52). The first reader / writer 18a notifies the base station apparatus 10 of information acquired through communication (S54). The terminal device 14 stops road-to-vehicle communication and vehicle-to-vehicle communication (S56). The base station apparatus 10 determines the change schedule (S58) and broadcasts the packet signal storing the change schedule (S60). When the pedestrian finishes crossing the pedestrian crossing and the pedestrian holds the terminal device 14 over the second reader / writer 18b, the terminal device 14 communicates with the second reader / writer 18b (S62). The second reader / writer 18b notifies the base station apparatus 10 of information acquired through communication (S64). The base station apparatus 10 determines a change schedule (S66) and broadcasts a packet signal storing the change schedule (S68). The terminal device 14 broadcasts the packet signal, and the base station device 10 receives the packet signal (S70).

  Next, a modified example of the present invention will be described. The modification of this invention is related with the communication system which also performs road-to-vehicle communication while performing vehicle-to-vehicle communication like an Example. In particular, the present invention relates to a terminal device that is carried by a pedestrian and has a short-range wireless communication function. The terminal device according to the embodiment stops the functions of vehicle-to-vehicle communication and road-to-vehicle communication over a period of crossing a pedestrian crossing. That is, when ITS transmission is unnecessary, notification of information necessary for ITS (hereinafter referred to as “ITS information”) is stopped. Similar to the embodiment, this modification also relates to stopping the notification of the ITS information when the ITS transmission is unnecessary. Here, the use of a company, a school, a hospital, or a public facility is assumed. When a pedestrian enters a company or the like, he / she notifies work by short-range wireless communication, and the notification of ITS information is stopped at that timing.

  On the other hand, when the pedestrian leaves the office or the like, the pedestrian notifies the exit by short-range wireless communication, and the notification of the ITS information is resumed at that timing. The communication system 100 according to the modification of the present invention is the same type as that in FIG. 1, the base station device 10 is the same type as that in FIG. 2, and the terminal device 14 is the same type as that in FIG. Note that the communication system 100 may not include the reader / writer 18, and the base station apparatus 10 does not include the acquisition unit 32, the reacquisition unit 34, the determination unit 38, and the traffic signal IF unit 48. Also good. Below, it demonstrates focusing on a difference.

  In the communication system 100, road-to-vehicle communication is performed between the base station device 10 and the terminal device 14, and vehicle-to-vehicle communication is performed between the plurality of terminal devices 14. Since these processes are the same as those in the embodiment, description thereof is omitted here. Below, the process at the time of a pedestrian going to work etc., carrying the terminal device 14 is demonstrated. FIG. 9 shows a configuration of a communication system 110 according to a modification of the present invention. The communication system 110 includes a terminal device 14, a reader / writer 18, and a management device 150.

  The reader / writer 18 is installed at a company reception. As described above, the reader / writer 18 performs short-range wireless communication and is connected to the management device 150. When a pedestrian goes to work with the terminal device 14, the pedestrian holds the terminal device 14 over the reader / writer 18. Near field communication is performed between the terminal device 14 and the reader / writer 18, and information regarding the terminal device 14 is transmitted from the terminal device 14 to the management device 150 via the reader / writer 18. When the management device 150 receives information on the terminal device 14, the management device 150 registers the attendance of the pedestrian carrying the terminal device 14. The terminal device 14 stops road-to-vehicle communication and vehicle-to-vehicle communication.

  On the other hand, the pedestrian holds the terminal device 14 over the reader / writer 18 when leaving. As described above, short-range wireless communication is performed between the terminal device 14 and the reader / writer 18, and information regarding the terminal device 14 is transmitted from the terminal device 14 to the management device 150 via the reader / writer 18. When the management device 150 receives information on the terminal device 14, the management device 150 registers the exit of the pedestrian carrying the terminal device 14. The terminal device 14 resumes road-to-vehicle communication and vehicle-to-vehicle communication.

  The management device 150 receives information related to the terminal device 14 by communicating with the terminal device 14 via the reader / writer 18. The management device 150 manages the attendance status of pedestrians who carry the terminal device 14 based on information regarding the terminal device 14. When the management device 150 receives information related to the terminal device 14 when the pedestrian's state is leaving, the management device 150 changes the pedestrian's state to work. In addition, when the management device 150 receives information on the terminal device 14 when the pedestrian's state is going to work, the management device 150 changes the pedestrian's state to withdrawal. Note that the reader / writer 18 may be installed in a school, a hospital, or a public facility instead of a company. The management device 150 manages information according to the place where the reader / writer 18 is installed. For example, attendance is going to school, reception, etc.

  Next, another modification of the present invention will be described. Another modification of the present invention also relates to a communication system that executes vehicle-to-vehicle communication and road-to-vehicle communication as in the embodiment. In particular, the present invention relates to a terminal device that is carried by a pedestrian and has a short-range wireless communication function. The terminal device according to the embodiment stops the functions of vehicle-to-vehicle communication and road-to-vehicle communication over a period of crossing a pedestrian crossing. Another modification also relates to stopping reporting of ITS information when ITS transmission is unnecessary, as in the embodiment. Here, it is assumed that transportation such as a train, a bus, and a taxi is used. When a pedestrian gets on a train or the like, the pedestrian executes a settlement process by short-range wireless communication, and the notification of the ITS information is stopped at that timing.

  On the other hand, when the pedestrian gets off from the train or the like, the pedestrian executes settlement processing by short-range wireless communication, and the ITS information notification is resumed. The communication system 100 according to the modification of the present invention is the same type as that in FIG. 1, and the base station apparatus 10 is the same type as that in FIG. Note that the communication system 100 may not include the reader / writer 18, and the base station apparatus 10 does not include the acquisition unit 32, the reacquisition unit 34, the determination unit 38, and the traffic signal IF unit 48. Also good.

  Description of road-to-vehicle communication and vehicle-to-vehicle communication is omitted here. Below, the process at the time of a pedestrian using a train, carrying the terminal device 14 is demonstrated. FIG. 10 shows a configuration of a communication system 120 according to another modification of the present invention. The communication system 120 includes a terminal device 14, a ticket gate 152, a network 202, and a payment server 154, and the ticket gate 152 includes a reader / writer 18.

  The reader / writer 18 is installed in the ticket gate 152. As described above, the reader / writer 18 performs short-range wireless communication and is connected to the management device 150. A pedestrian holds the terminal device 14 over the reader / writer 18 when carrying the terminal device 14 and passing through the ticket gate 152 for boarding. By performing short-range wireless communication between the terminal device 14 and the reader / writer 18, the terminal device 14 and the payment server 154 execute a payment process via the network 202. Since a publicly known technique may be used for the settlement process, the description is omitted here. Thereafter, the terminal device 14 stops road-to-vehicle communication and vehicle-to-vehicle communication.

  On the other hand, the pedestrian holds the terminal device 14 over the reader / writer 18 when carrying the terminal device 14 and passing through another ticket gate 152 for getting off. As described above, short-distance wireless communication is performed between the terminal device 14 and the reader / writer 18, whereby the terminal device 14 and the settlement server 154 perform settlement processing via the network 202. The terminal device 14 resumes road-to-vehicle communication and vehicle-to-vehicle communication.

  The settlement server 154 settles the fare with the terminal device 14 by communicating with the terminal device 14 via the reader / writer 18 and the network 202. The settlement server 154 confirms the pedestrian boarding station by executing a settlement process with the terminal device 14 when boarding. In addition, the settlement server 154 confirms the pedestrian exit station by executing a settlement process with the terminal device 14 when getting off. Furthermore, the settlement server 154 stores a fare table in advance, and derives the fare from the boarding station to the departure station based on the table. The settlement server 154 subtracts the amount corresponding to the derived fare from the pedestrian's electronic money.

  FIG. 11 shows the configuration of the terminal device 14. In the terminal device 14, a settlement unit 86 is further added to the terminal device 14 of FIG. The settlement unit 86 performs a communication with the external settlement server 154 via the second wireless communication unit 82 to settle the service usage fee, that is, the fare. Here, the second wireless communication unit 82 performs communication when entering the service providing area and when leaving the service providing area. The former means passing through the ticket gate 152 when getting on, and the latter corresponds to passing through the ticket gate 152 during the latter. The control unit 84 communicates with the second wireless communication unit 82 when passing the ticket gate 152 when boarding, and then communicates with the second wireless communication unit 82 when passing the ticket gate 152 with the latter. In the meantime, the operation of the first wireless communication unit 80 is stopped.

  FIG. 12 is a sequence diagram illustrating a communication procedure in the communication system 120. This corresponds to a processing procedure for boarding. The terminal device 14 notifies a packet signal for vehicle-to-vehicle communication (S100). The terminal device 14 and the reader / writer 18 execute communication (S102), and the terminal device 14 and the payment server 154 execute a payment process (S104). The terminal device 14 stops the notification for vehicle-to-vehicle communication (S106).

  FIG. 13 is a sequence diagram illustrating another communication procedure in the communication system 120. This corresponds to the processing procedure at the time of getting off, and is processing following FIG. The terminal device 14 stops the notification for vehicle-to-vehicle communication (S120). The terminal device 14 and the reader / writer 18 execute communication (S122), and the terminal device 14 and the payment server 154 execute a payment process (S124). The terminal device 14 notifies a packet signal for vehicle-to-vehicle communication (S126).

  Next, still another modification of the present invention will be described. Still another modified example of the present invention relates to a communication system that executes vehicle-to-vehicle communication and road-to-vehicle communication as in the embodiment. In particular, the present invention relates to a terminal device that is carried by a pedestrian and has a short-range wireless communication function. The terminal device according to the embodiment stops the functions of vehicle-to-vehicle communication and road-to-vehicle communication over a period of crossing a pedestrian crossing. Still another modified example relates to stopping reporting of ITS information when ITS transmission is unnecessary, as in the embodiment. Here, it is assumed that there are pedestrians in a train, bus, taxi, or other vehicle or building.

  FIG. 5B shows the structure of the message header. Of these, the “RSU transmission period length” is a period for which the terminal device 14 is prohibited from transmitting (hereinafter referred to as “transmission prohibited period”). It is shown. In yet another modification, a simple base station apparatus 10 is installed in an area where ITS transmission is prohibited, such as in a car or a building, using this. The transmission power of the simple base station apparatus 10 is smaller than that of the normal base station apparatus 10 so that the inside of the vehicle or the building is a service area. The simple base station apparatus 10 broadcasts the RSU packet signal, and at that time, a transmission prohibition period is set for the entire period. The base station apparatus 10 may have antenna directivity that is limited to the inside of a vehicle or a building. When receiving the RSU packet signal, the terminal device 14 sets a transmission prohibition period for the entire period. This corresponds to the terminal device 14 not notifying the packet signal while receiving the RSU packet signal.

  On the other hand, the RSU packet signal notified from the simple base station apparatus 10 may be received by the terminal apparatus 14 mounted on the vehicle 12. At that time, the terminal device 14 mounted on the vehicle 12 should continue notifying the packet signal without stopping the notification. In order to deal with this, the simple base station device 10 represents information for the terminal device 14 carried by the pedestrian (hereinafter referred to as “for pedestrian”) in the reserved area of the RSU packet signal. Include the identifier. When the terminal device 14 carried by the pedestrian confirms the identifier, the terminal device 14 sets a transmission prohibition period for the entire period. However, when the terminal device 14 mounted on the vehicle 12 confirms the identifier, the RSU packet signal Is discarded. The communication system 100 according to the modification of the present invention is the same type as that in FIG. 1, the base station device 10 is the same type as that in FIG. 2, and the terminal device 14 is the same type as that in FIG. Note that the communication system 100 may not include the reader / writer 18, and the base station apparatus 10 does not include the acquisition unit 32, the reacquisition unit 34, the determination unit 38, and the traffic signal IF unit 48. Also good. The same applies to the simple base station apparatus 10.

  In FIG. 2, the generation unit 46 of the simple base station apparatus 10 generates a packet signal as described above. The generation unit 46 includes an identifier for representing information for pedestrians in the packet signal, and sets a transmission prohibition period for the entire period. This corresponds to setting a transmission prohibition period for the terminal device 14 carried by a pedestrian, and corresponds to setting a transmission prohibition period excluding the terminal device 14 mounted on the vehicle 12 from the target. To do. The modem unit 24 and the RF unit 22 broadcast the packet signal generated by the generation unit 46.

  In FIG. 6, the RF unit 52 and the modem unit 54 of the terminal device 14 mounted on the vehicle 12 receive the packet signal from the base station device 10. The timing specifying unit 60 determines a packet signal transmittable period based on information included in the packet signal. Specifically, the transmittable period is set in a period other than the transmission prohibited period. Note that CSMA is performed within the transmittable period. When the received packet signal includes an identifier for representing information for pedestrians, the timing specifying unit 60 ignores the transmission prohibition period included in the packet signal and transmits the packet signal. Determine the possible period. The modem unit 54 and the RF unit 52 broadcast the packet signal in the determined transmittable period.

  FIG. 14 is a flowchart showing a setting procedure of the terminal device 14 according to still another modified example of the present invention. The RF unit 52 and the modem unit 54 receive the packet signal (S150). The timing specifying unit 60 extracts information related to the transmission prohibition period (S152). If the identifier for pedestrians is included in the packet signal (Y in S154), the timing specifying unit 60 reflects the transmission prohibition period (S156) and sets the transmittable period (S160). On the other hand, if the identifier for pedestrians is not included in the packet signal (N in S154), the timing specifying unit 60 discards the transmission prohibition period (S158) and sets the transmission possible period (S160).

  According to the embodiment of the present invention, since information is acquired through short-range wireless communication from a terminal device having a short-range wireless communication function in addition to a vehicle-to-vehicle communication function, walking with the terminal device carried It can be accurately recognized that the person enters the pedestrian crossing. Moreover, since the change schedule is determined based on the information acquired from the terminal device, it is possible to determine the change schedule suitable for pedestrian crossing. Moreover, since the change schedule suitable for a pedestrian crossing is determined, the probability of a rear-end collision between a pedestrian and a vehicle can be reduced. Moreover, since the change schedule suitable for a pedestrian crossing is notified, it can notify correctly that a pedestrian approachs a pedestrian crossing. In addition, since the change schedule is determined based on the information about the pedestrian so that the lighting interval of each lighting color changes, the change schedule suitable for the pedestrian can be determined. Moreover, since the change schedule suitable for a pedestrian is notified, safety can further be improved. Moreover, since the change schedule suitable for a pedestrian is notified, a traffic weak person can be protected.

  Moreover, since information is re-acquired from the same terminal device within a certain period after the information is acquired, it can be accurately recognized that a pedestrian carrying the terminal device leaves the pedestrian crossing. In addition, since the change schedule is determined based on the information reacquired from the terminal device, it is possible to determine the change schedule suitable for traveling of the vehicle. Further, since the determined change schedule is notified, it is possible to accurately notify that the pedestrian leaves the pedestrian crossing. Moreover, since the change schedule according to whether the pedestrian crosses the pedestrian crossing is notified, driving according to the change schedule can be urged. In addition, driving according to the change schedule is urged, so the driver's stress can be reduced. In addition, since driving according to the change schedule is urged, traffic congestion can be reduced. Moreover, since the driving | operation according to a change schedule is encouraged, the discharge | emission amount of a carbon dioxide can be reduced. Further, since a commercially available reader / writer can be used, the feasibility can be improved.

  In addition, since the inter-vehicle communication is stopped until the predetermined period elapses after the short-range wireless communication ends, the power consumption can be reduced. Further, since the power consumption is reduced, the battery driving time can be extended. In addition, since inter-vehicle communication is stopped when entering a pedestrian crossing, power consumption during crossing of the pedestrian crossing can be reduced. Moreover, since vehicle-to-vehicle communication is resumed when leaving the pedestrian crossing, position information can be notified after the crossing is completed. Moreover, since vehicle-to-vehicle communication is resumed when a predetermined period has elapsed, the position information can be automatically notified.

  In addition, when working at a company, attendance confirmation is executed by short-range wireless communication, and inter-vehicle communication is stopped, so both processes can be executed together. Further, since the vehicle-to-vehicle communication is stopped by short-range wireless communication when working at the company, the vehicle-to-vehicle communication in the company can be stopped. Moreover, since both processes are performed collectively, the convenience of a pedestrian can be improved. In addition, since reader / writers are installed in schools, hospitals, public facilities, etc., inter-vehicle communication can be stopped in various places.

  Moreover, since the settlement of the fare is executed at the time of boarding and the inter-vehicle communication is stopped, both processes can be executed together. Further, since the inter-vehicle communication is stopped when boarding, the inter-vehicle communication during boarding can be stopped. Moreover, since the settlement of the fare is executed at the time of getting off and the inter-vehicle communication is resumed, both processes can be executed together. Further, since the whole base period is set as the transmission prohibition period in the simple base station apparatus, the inter-vehicle communication can be stopped around the place where the simple base station apparatus is installed. Moreover, since the whole period is set as a transmission prohibition period and an identifier representing information for pedestrians is included in the packet signal, transmission can be stopped only for terminal devices carried by pedestrians. . Moreover, since transmission is stopped only for the terminal device carried by the pedestrian, the inter-vehicle communication can be continued by the terminal device mounted on the 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 the combination of each component and each processing process, and such modifications are also within the scope of the present invention. .

  In another modification of the present invention, the reader / writer 18 is provided in the ticket gate 152, and the settlement server 154 executes a fare settlement process. In other words, it is applied to transportation. However, the present invention is not limited to this. For example, the present invention may be applied not to transportation facilities but to service providing facilities such as movies and theaters. At that time, the reader / writer 18 is provided for reception, and the settlement server 154 executes settlement processing for the entrance fee. According to this modification, the present invention can be applied to various services.

  10 base station device, 12 vehicle, 14 terminal device, 16 traffic light, 18 reader / writer, 20 antenna, 22 RF unit, 24 modulation / demodulation unit, 26 processing unit, 30 control unit, 32 acquisition unit, 34 reacquisition unit, 36 network communication Unit, 38 determination unit, 40 frame definition unit, 42 selection unit, 46 generation unit, 48 signal IF unit, 50 antenna, 52 RF unit, 54 modulation / demodulation unit, 56 processing unit, 60 timing identification unit, 64 generation unit, 66 extraction Unit, 68 carrier sense unit, 70 transfer determination unit, 72 acquisition unit, 80 first radio communication unit, 82 second radio communication unit, 84 control unit, 100 communication system.

Claims (1)

A terminal device that can be carried by a pedestrian,
A first communication unit that performs first wireless communication that broadcasts a packet signal that stores information including the position of the terminal device in order to communicate with the vehicle-mounted device or the roadside device ;
A second communication unit that communicates information by second wireless communication having a communication area narrower than that of the first wireless communication;
And a control unit for controlling the operation of the operation and the second communication unit of the first communication unit,
The second communication unit is configured to be able to communicate with the external communication device installed in a predetermined area where the first wireless communication is unnecessary, by the second wireless communication, and the terminal device In the case of entering the area and in the case of leaving the area, communication is performed with the second wireless communication with the external communication device,
The control unit is configured to receive the packet from the first communication unit during a period from when the second communication unit communicates when entering the area until when the second communication unit communicates when leaving the area. A terminal device characterized by stopping broadcast transmission of a signal.

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