JP6037194B2 - On-board device, mobile terminal device - Google Patents

Description

The present invention relates to a vehicle- mounted device and a mobile terminal device suitable for exchanging information around a vehicle .

  There are many blind spots from the seats of vehicles, and many accidents that come into contact with people when starting the vehicle occur. In particular, children are difficult to find because they are short. Contact accidents occur not only when starting, but also when parking and opening and closing doors.

JP 2006-209478 A

  The present invention has been made in view of such a situation, and an object thereof is to provide a technique for a driver to accurately grasp the situation around the vehicle.

  A wireless device according to an aspect of the present invention is a wireless device to be possessed by a person or an animal, and a transmitter that transmits a presence signal for recognizing the presence of the person or the animal with a designated transmission power. A reception unit that receives a search signal for searching for a radio device possessed by a person or an animal from a radio device mounted on the vehicle, and a transmission power control unit that reduces the transmission power of the presence signal when the search signal is received And comprising.

  Another aspect of the present invention is also a wireless device. This device is a wireless device to be mounted on a vehicle, and transmits a search signal for searching for a wireless device possessed by a person or an animal present around the vehicle, and a wireless device that has received the search signal. A receiving unit that receives a presence signal indicating the presence of a person or an animal from the device, and a notification unit that notifies a person in the vehicle of the presence of a person or an animal around the vehicle based on the presence signal.

  Yet another embodiment of the present invention is also a wireless device. This device is a wireless device to be possessed by a person or an animal, and is a wireless device possessed by a person or an animal from a transmitter that transmits a presence signal indicating the presence of the person or animal and a wireless device mounted on a vehicle. A receiving unit that receives a search signal for searching for a device. The wireless device and the wireless device mounted on the vehicle mutually hold identification information. A receiving part receives the search signal containing both identification information from the radio | wireless apparatus mounted in the vehicle. The transmission unit transmits a plurality of presence signals each including identification information of the both with a plurality of different types of transmission power.

  Yet another embodiment of the present invention is also a wireless device. This device is a wireless device to be mounted on a vehicle, and includes a transmitter that transmits a search signal for searching for a wireless device possessed by a person or an animal, and a wireless device that has received the search signal. And a receiving unit that receives a presence signal indicating the presence of. The wireless device and the wireless device possessed by a person or animal hold identification information with each other. A transmission part transmits the search signal containing both identification information. The reception unit receives a plurality of presence signals each including identification information of both transmitted from a wireless device possessed by a person or an animal with a plurality of different types of transmission power. When the receiving unit receives the presence signal including the identification information of both transmitted with the lowest transmission power among the plurality of types of transmission power, the transmission unit ends the transmission of the search signal.

  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 driver can accurately grasp the situation around the vehicle.

It is a figure for demonstrating the outline | summary of the proximity search service by the communication system which concerns on embodiment of this invention. It is a figure which shows the structure of the radio | wireless apparatus which should be mounted in the vehicle based on embodiment of this invention. It is a figure which shows the structure of the radio | wireless apparatus which the pedestrian should hold | maintain based on embodiment of this invention. It is a figure for demonstrating the specific example of the proximity search service by the communication system which concerns on embodiment of this invention. FIG. 5A shows an example of the data structure of normal transmission a shown in FIG. FIG. 5B is a diagram illustrating a data structure example of the short-distance transmission illustrated in FIG. It is a figure which shows an example of the warning message notified from the user interface of onboard equipment. It is a figure for demonstrating the outline | summary of the waiting service by the communication system which concerns on embodiment of this invention. It is a figure for demonstrating the specific example 1 of the waiting service by the communication system which concerns on embodiment of this invention. FIG. 9A is a diagram illustrating a data structure example of normal transmission of the vehicle-mounted device illustrated in FIG. FIG. 9B is a diagram illustrating a data structure example of normal transmission of the pedestrian terminal illustrated in FIG. 8. FIG. 9C is a diagram illustrating a data structure example of short-distance transmission of the pedestrian terminal illustrated in FIG. 8. FIG. 10A is a diagram for explaining a first method for estimating the distance between the vehicle-mounted device and the pedestrian terminal. FIG. 10B is a diagram for explaining a second method for estimating the distance between the vehicle-mounted device and the pedestrian terminal. It is a figure for demonstrating the specific example 2 of the waiting service by the communication system which concerns on embodiment of this invention. It is a figure for demonstrating the 1st search method using directivity. It is a figure for demonstrating the 2nd search method using directivity.

  FIG. 1 is a diagram for explaining an overview of a proximity search service application (hereinafter simply referred to as a proximity search service) by a communication system according to an embodiment of the present invention. The communication system includes a wireless device (hereinafter referred to as an on-vehicle device) mounted on the vehicle 100 and a wireless device carried or carried by a person (hereinafter referred to as a pedestrian terminal as appropriate). In FIG. 1, a vehicle-mounted device (not shown) is mounted on the vehicle 100. There are a first pedestrian 201, a second pedestrian 202, a third pedestrian 203, and a fourth pedestrian 204 around the vehicle 100. The first pedestrian 201, the second pedestrian 202, the third pedestrian 203, and the fourth pedestrian 204 each have a pedestrian terminal. In this embodiment, children are mainly targeted as pedestrians who possess pedestrian terminals, but people with reduced judgment and physical functions, such as elderly people and sick people, are likely to become blind spots from drivers. You may add a short person to the subject. Of course, an adult healthy person may be added to the target.

  In FIG. 1, a blind spot zone Z <b> 1 indicates an area that becomes a blind spot from the driver of the vehicle 100. The first pedestrian 201 and the third pedestrian 203 are in the blind spot zone Z1. When the driver moves the vehicle 100 forward or backward as it is, there is a possibility that the driver contacts the first pedestrian 201 or the third pedestrian 203. The second pedestrian 202 is in the vicinity of the vehicle 100 but is in a position that can be seen by the driver. The fourth pedestrian 204 is at a safe position relatively far from the vehicle 100.

  In the example of FIG. 1, an object is to detect a pedestrian within a radius of 5 to 10 m from the vehicle 100. Therefore, the pedestrian terminal held by each pedestrian may send a signal indicating its presence with the radio wave intensity reaching within a radius of 5 to 10 m. In FIG. 1, a first area Ac1, a second area Ac2, a third area Ac3, and a fourth area Ac4 are a first pedestrian 201, a second pedestrian 202, a third pedestrian 203, and a fourth pedestrian 204, respectively. Indicates the radio wave range at the time of short-distance transmission of the pedestrian terminals held respectively. Near-field transmission refers to transmission with lower transmission power than normal transmission. Details of the short-distance transmission will be described later.

  In FIG. 1, the radio wave by the short-distance transmission of the pedestrian terminal held by the fourth pedestrian 204 does not reach the vehicle-mounted device mounted on the vehicle 100. On the other hand, the radio wave by the short-distance transmission of the pedestrian terminal which the 1st pedestrian 201, the 2nd pedestrian 202, and the 3rd pedestrian 203 hold | maintain reaches the onboard equipment mounted in the vehicle 100. FIG. Therefore, the vehicle-mounted device can detect that there are three pedestrians within a radius of 5 to 10 m from the vehicle 100. The vehicle-mounted device can call attention by notifying the driver of this fact.

  FIG. 2 is a diagram showing a configuration of radio apparatus 10 to be mounted on vehicle 100 according to the embodiment of the present invention. For example, an in-vehicle device used in ITS (Intelligent Transport Systems) can be used as the wireless device 10. In ITS, the use of a wireless LAN compliant with a standard such as IEEE802.11 is under consideration. In such a wireless LAN, an access control function called CSMA / CA (Carrier Sense Multiple Access with Collision Avidance) is used. Therefore, in the wireless LAN, the same wireless channel is shared by a plurality of vehicle-mounted devices and a plurality of pedestrian terminals (see FIG. 3). In such CSMA / CA, after confirming that no other packet signal is transmitted by carrier sense, the packet signal is transmitted by broadcast (hereinafter, transmission of the packet signal by broadcast is referred to as “notification”).

  In FIG. 2, the wireless device 10 includes an antenna 11, an RF unit 12, a modem unit 13, a processing unit 14, a status information acquisition unit 15, a user interface 16, and a control unit 17. The processing unit 14 includes a search signal generation unit 141, a presence signal analysis unit 142, an action instruction signal generation unit 143, and a distance calculation unit 144.

  The configuration of the RF unit 12, the modulation / demodulation unit 13, the processing unit 14, the status information acquisition unit 15 and the control unit 17 can be realized by an arbitrary processor, memory, or other LSI in terms of hardware, and memory in terms of software. This is realized by a program loaded on the system, but here, functional blocks realized by their cooperation are depicted. 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.

  The RF unit 12 receives a packet signal from another wireless device by the antenna 11 as a reception process. The RF unit 12 performs frequency conversion on the received radio frequency packet signal to generate a baseband packet signal. The RF unit 12 outputs a baseband packet signal to the modem unit 13. In general, since a baseband packet signal is formed by an in-phase component and a quadrature component, two signal lines should be shown. However, in order to simplify the drawing, only one signal line is shown in FIG. Show. The RF unit 12 includes an LNA (Low Noise Amplifier), a mixer, an AGC, an A / D conversion unit, and the like (not shown) as components of the reception system.

  The RF unit 12 transmits the generated packet signal from the wireless device 10 as a transmission process. In this embodiment, the transmission power is fixed, and the transmission power is a power with a radius of 100 m as a reception range. The RF unit 12 performs frequency conversion on the baseband packet signal input from the modem unit 13 to generate a radio frequency packet signal. The RF unit 12 transmits a radio frequency packet signal from the antenna 11. The RF unit 12 includes a PA (Power Amplifier), a mixer, a D / A conversion unit, and the like (not shown) as components of the transmission system.

  The modem unit 13 demodulates the baseband packet signal from the RF unit 12 as a reception process. The modem unit 13 outputs the demodulated packet signal to the processing unit 14. Further, the modem unit 13 performs modulation on the packet signal from the processing unit 14 as transmission processing. The modem unit 13 outputs the modulated packet signal to the RF unit 12 as a baseband packet signal.

  The communication system according to the present embodiment employs an OFDM (Orthogonal Frequency Division Multiplexing) modulation scheme. In this case, the modem unit 13 performs FFT (Fast Fourier Transform) as a reception process, and performs IFFT (Inverse Fast Fourier Transform) as a transmission process.

  The processing unit 14 processes application data included in the packet signal output from the modem unit 13 as a reception process. Further, the processing unit 14 outputs a packet signal including the generated application data to the modem unit 13 as a transmission process. Further, the status information acquired by the status information acquisition unit 15 is input to the processing unit 14. In addition, the processing unit 14 outputs information to be notified to people (drivers and passengers) in the vehicle 100 to the user interface 16.

  The status information acquisition unit 15 acquires status information in the vehicle 100 from various sensors in the vehicle 100 and an ECU (Electronic Control Unit). For example, engine start information, door opening / closing information, and the like are acquired.

  The user interface 16 includes a display unit, an input unit, an audio output unit, and the like. In the present embodiment, the user interface 16 displays and / or outputs voice information such as pedestrian information existing in the vicinity of the vehicle 100 generated by the processing unit 14. The control unit 17 controls processing of the entire wireless device 10.

  Hereinafter, the processing unit 14 will be described more specifically. The search signal generation unit 141 generates a search signal for searching for the wireless device 20 possessed by a pedestrian existing around the vehicle 100. The search signal generation unit 141 includes at least information indicating that the search signal is a signal related to the vehicle-mounted device ID indicating the transmission source and the proximity search service. The search signal generated by the search signal generation unit 141 is stored in the application data area of the packet signal, and after the header and footer of each layer are added, it is notified from the RF unit 12 via the antenna 11.

  The search signal is generated when the proximity search service is activated. The neighborhood search service is activated when the movement of the vehicle 100 is predicted to change. More specifically, the neighborhood search service is activated due to a change in the state of the vehicle 100 specified by the status information input from the status information acquisition unit 15. The state change may cause the vehicle 100 to predict a change from the stopped state to the traveling state. Examples of the state change include engine start, door close, transmission parking to drive or back, side brake release, and the like. These are operations at a stage before starting, and a change in the state of the vehicle 100 due to the operation makes it predicted to start. Further, the state change described above may be a prediction of a change in travel speed (that is, a change from low speed to high speed or a change from high speed to low speed). Examples of the state change include a change in the accelerator depression angle and a change in the output of the speedometer. Further, the neighborhood search service may be activated based on a driver's instruction via the user interface 16.

  The presence signal analysis unit 142 analyzes a presence signal indicating the presence of a pedestrian included in a packet signal notified from the pedestrian terminal that has received the search signal. The presence signal includes at least a pedestrian terminal ID indicating a transmission source. The presence signal analysis unit 142 temporarily holds the pedestrian terminal ID that can be received during the neighborhood search service. Specifically, it is held until the neighborhood search service ends. The presence signal analysis unit 142 counts the number of presence signals that can be received during the short distance transmission mode.

  As will be described later, when the pedestrian terminal receives the search signal from the vehicle-mounted device, the pedestrian terminal transmits a presence signal in the short-distance transmission mode. Therefore, the presence signal analysis unit 142 counts the number of presence signals that can be received during the proximity search service, thereby determining the number of pedestrians present in the vicinity of the vehicle 100 (radius 5 to 10 m in the present embodiment). Can be identified. In addition, even if a packet signal including a presence signal is notified from a pedestrian terminal that has received the search signal, if the pedestrian terminal does not exist in the vicinity of the vehicle 100, radio waves do not reach the vehicle-mounted device, and thus are not counted. It becomes.

  A notification information generation unit (not shown) generates notification information for display and / or audio output based on the number of pedestrians and outputs the notification information to the user interface 16. The user interface 16 notifies the notification information to persons (drivers and passengers) in the vehicle 100.

  The action instruction signal generation unit 143 generates a signal for instructing an action to be executed by the pedestrian terminal. Examples of the action include vibration, output of a warning sound (including a warning message), predetermined information display (for example, display of an estimated distance to the vehicle-mounted device), and the like. The action instruction signal generation unit 143 includes at least information on the pedestrian terminal ID indicating the transmission destination and the action content to be executed by the pedestrian terminal in the action instruction signal. This pedestrian terminal ID is a pedestrian terminal ID held by the presence signal analysis unit 142.

  The action instruction signal generated by the action instruction signal generation unit 143 is stored in the application data area of the packet signal, and after the header and footer of each layer are added, the action instruction signal is transmitted from the RF unit 12 via the antenna 11. This transmission is executed together with the notification by the user interface 16. Further, this transmission may be unicast transmission or broadcast transmission. The pedestrian terminal can determine whether or not the action instruction signal is addressed to itself based on the pedestrian terminal ID included in the packet signal.

  The distance calculation unit 144 calculates the estimated distance between the pedestrian terminal and the vehicle-mounted device based on the received radio wave intensity from the pedestrian terminal or the time variation of the received radio wave intensity. This estimated distance can be included in the action instruction signal.

  When the processing unit 14 receives a packet signal notified from the vehicle-mounted device instead of the pedestrian terminal during the neighborhood search service, the processing unit 14 discards the packet signal. When the transmission source ID included in the packet signal is the vehicle-mounted device ID, the processing unit 14 can determine that the packet signal is notified from the vehicle-mounted device instead of the pedestrian terminal.

  FIG. 3 is a diagram illustrating a configuration of the wireless device 20 that a pedestrian should hold according to the embodiment of the present invention. In the present embodiment, a small, lightweight, low power consumption dedicated terminal is assumed. For example, assume a terminal that can be worn around the neck, lowered into a key folder, or placed in a pocket. In FIG. 3, the wireless device 20 includes an antenna 21, an RF unit 22, a modem unit 23, a processing unit 24, a user interface 25, and a control unit 26. The processing unit 24 includes a presence signal generation unit 241, a search signal analysis unit 242, an action instruction signal analysis unit 243, an action execution unit 244, and a transmission power control unit 245.

  The configuration of the RF unit 22, the modulation / demodulation unit 23, the processing unit 24, and the control unit 26 can be realized by an arbitrary processor, memory, or other LSI in terms of hardware, and a program loaded in the memory in terms of software, etc. Here, functional blocks realized by their cooperation are depicted. 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.

  The antenna 21, the RF unit 22, and the modem unit 23 are basically in common with the configuration and operation of the antenna 11, the RF unit 12, and the modem unit 13 of FIG. Hereinafter, these components will be described focusing on the differences. In the present embodiment, the transmission power of the pedestrian terminal has a variable configuration unlike the vehicle-mounted device.

  The processing unit 24 processes application data included in the packet signal output from the modem unit 23 as a reception process. Further, the processing unit 24 outputs a packet signal including the generated application data to the modem unit 23 as a transmission process. In addition, when the received packet signal includes the action instruction signal, the processing unit 24 outputs information for executing a predetermined action to the user interface 25.

  The user interface 25 preferably includes a vibration unit and / or an audio output unit. In the present embodiment, basically, the main purpose is to make the pedestrian recognize that the vehicle 100 starts to move, so it is preferable to notify the pedestrian of the information in a manner that the pedestrian can more easily recognize. Therefore, it is effective to notify the information by vibration or warning sound (including warning message). The user interface 25 may be provided with a display unit. When the estimated distance between the vehicle-mounted device and the pedestrian terminal is transmitted from the vehicle-mounted device, the estimated distance can be displayed on the display unit. In addition, when a display part is not provided from viewpoints, such as cost, the estimated distance is read by the audio | voice output part. The control unit 26 controls processing of the entire wireless device 20.

  Hereinafter, the processing unit 24 will be described more specifically. The presence signal generation unit 241 generates a presence signal for recognizing the presence of a pedestrian in the surroundings. The presence signal generation unit 241 includes at least a pedestrian terminal ID indicating a transmission source and a transmission mode in the presence signal. In the present embodiment, two types of transmission modes, a normal transmission mode and a short-distance transmission mode, are assumed. The former is a mode in which transmission is performed using transmission power having a radius of 100 m as a reception range, and the latter is a mode in which transmission is performed using transmission power having a radius of 5 to 10 m as a reception range.

  In this embodiment, since a position detection system such as GPS (Global Positioning System) is not mounted on the pedestrian terminal, the presence signal does not include position information (for example, latitude / longitude information).

  The presence signal generated by the presence signal generation unit 241 is stored in the application data area of the packet signal, and after the header and footer of each layer are added, the presence unit is notified from the RF unit 22 via the antenna 21. This notification is executed in the normal transmission mode. This notification may be performed periodically or according to CSMA / CA. Alternatively, a clock or illuminometer may be provided to detect the nighttime zone, and only the nighttime zone may be executed. Moreover, a vibration detection sensor may be provided and executed only when a pedestrian is moving. Packet signals including presence signals that are broadcast in the normal transmission mode are received by on-board devices installed in a running vehicle, roadside devices installed in traffic lights, and other access points, and are used for various applications. Is done. For example, it is used for an application for notifying the presence of a pedestrian to a traveling vehicle, an application for searching for lost children, and the like.

  The search signal analysis unit 242 analyzes the search signal included in the packet signal notified from the vehicle-mounted device. The fact that the packet signal including the search signal could be received means that the pedestrian terminal is located within a radius of several hundred meters from the vehicle-mounted device. The search signal analysis unit 242 temporarily holds the vehicle-mounted device ID included in the search signal. Specifically, it is held until the neighborhood search service ends. The search signal analysis unit 242 notifies the transmission power control unit 245 that the search signal has been received.

  Upon receiving the notification, the transmission power control unit 245 reduces the transmission power of the packet signal including the presence signal. Specifically, the transmission power is reduced to power that generates a transmission radio wave having a transmission distance corresponding to a safe distance between the vehicle 100 and the pedestrian. The safety distance may be considered as a radius of a safety area formed around the vehicle 100. In the present embodiment, when receiving the above notification, transmission power control section 245 switches the transmission mode from the normal transmission mode to the short-distance transmission mode. When the transmission mode is the short-distance transmission mode, the presence signal generation unit 241 further includes the vehicle-mounted device ID indicating the destination in the presence signal. This onboard equipment ID is the onboard equipment ID held in the search signal analysis unit 242.

  The action instruction signal analysis unit 243 analyzes the action instruction signal included in the packet signal notified from the vehicle-mounted device, and notifies the action execution unit 244 of the analysis result. The action execution unit 244 causes the user interface 25 to execute an action based on the analysis result. For example, as the user interface 25, a vibrator is vibrated or a warning sound is output.

  FIG. 4 is a diagram for explaining a specific example of the proximity search service by the communication system according to the embodiment of the present invention. In this example, there are two vehicles (vehicle A, vehicle B) and three pedestrians (pedestrian A1, pedestrian A2, pedestrian B1). Each of the two vehicles is equipped with the above-described vehicle-mounted device, and three pedestrians hold the above-described pedestrian terminals. Vehicle A, pedestrian A1, and pedestrian A2 are located at a relatively short distance. The vehicle B and the pedestrian B1 are also located at a relatively short distance. The A group of the vehicle A, the pedestrian A1 and the pedestrian A2 and the B group of the vehicle B and the pedestrian B1 are located several tens of meters apart.

  When the engine of the vehicle A is started or the door is closed, the proximity search service is activated in the vehicle-mounted device (hereinafter referred to as the vehicle-mounted device A) mounted on the vehicle A. The search signal generation unit 141 of the on-vehicle device generates a search signal. The packet signal including the search signal is notified from the RF unit 12 via the antenna 11. In the present embodiment, the transmission power of the in-vehicle device is fixed and corresponds to the transmission power in the normal transmission mode of the pedestrian terminal (may be coincident). All notifications are denoted as normal transmission. Since radio waves transmitted from the vehicle-mounted device reach a radius of several hundred meters, pedestrian terminals (hereinafter referred to as pedestrian terminal A1, pedestrian terminal A2, pedestrian terminal) held by pedestrian A1, pedestrian A2 and pedestrian B1. B1) and the vehicle-mounted device mounted on vehicle B (hereinafter referred to as vehicle-mounted device B).

  Since the vehicle-mounted device does not respond to the search signal including the vehicle-mounted device ID (that is, to ignore), the vehicle-mounted device B discards the packet signal including the search signal. In the pedestrian terminal A1, the pedestrian terminal A2, and the pedestrian terminal B1, the transmission mode is switched from the normal transmission mode to the short-distance transmission mode with the reception of the packet signal.

  FIG. 5A shows an example of the data structure of the normal transmission a shown in FIG. FIG. 5B shows an example of the data structure of the short distance transmission shown in FIG. Normal transmission a shown in FIG. 5A is an example of a data structure when transmitting a search signal from the vehicle-mounted device. In this example, “service type”, “transmission mode”, “transmission source ID”, and “destination ID” are defined as items, and the contents include “neighbor search (request)”, “normal”, “in-vehicle device” “ID” and “any” are set. This normal transmission a transmits a search signal. The normal transmission b in FIG. 4 is for transmitting an action instruction signal. Although the data structure example of the normal transmission b is not shown, “neighbor search (action instruction)” is set as the content of “service type”, and “pedestrian terminal ID” is set as the content of “destination ID”. The “pedestrian terminal ID” is the pedestrian terminal ID of the pedestrian terminal that has received the presence signal. Furthermore, “action content” is added as an item, and “specific action” is set as the content. In the example of FIG. 4, “vibration” is set.

  Short-range transmission shown in FIG. 5B is an example of a data structure when transmitting a presence signal from a pedestrian terminal that has received a search signal. In this example, “service type”, “transmission mode”, “transmission source ID”, and “destination ID” are defined as items, and the contents include “neighbor search (response)”, “short distance”, “walking” User terminal ID "and" vehicle equipment ID "are set. In the example of the data structure of normal transmission of the pedestrian terminal, “notification” is set in the content of “service type” and “any” is set in the content of “destination ID”, although not shown.

  Returning to FIG. 4, pedestrian terminal A1, pedestrian terminal A2, and pedestrian terminal B1 transmit a packet signal including a presence signal by short-distance transmission. Among these, the radio waves from the pedestrian terminal A1 and the pedestrian terminal A2 reach the vehicle-mounted device A, but the radio waves from the pedestrian terminal B1 do not reach the vehicle-mounted device A. The radio wave from the pedestrian terminal B1 reaches the vehicle-mounted device B. However, since the vehicle-mounted device B is not the execution subject of the proximity search service, the packet signal from the short distance transmission from the pedestrian terminal B1 is ignored. More specifically, when the vehicle-mounted device ID of the vehicle-mounted device B does not match the vehicle-mounted device ID that is the destination ID included in the short-range transmission, the short-range transmission is ignored.

  When the vehicle-mounted device A receives the packet signal by the short-distance transmission from the pedestrian terminal A1 and the pedestrian terminal A2, it counts the number of presence signals that can be received by the short-distance transmission, and the pedestrian located in the vicinity of the vehicle A Identify the number of people. In the example of FIG. 4, there are two people.

  FIG. 6 shows an example of a warning message notified from the user interface 16 of the vehicle-mounted device A. FIG. 6 shows an example in which a warning message “There are two people near the danger” is displayed on the display unit as the user interface 16.

  Returning to FIG. 4, the vehicle-mounted device A transmits a packet signal including an action instruction signal by the normal transmission b. This normal transmission b may be unicast transmission or broadcast transmission. Since the pedestrian terminal ID of the pedestrian terminal A1 and the pedestrian terminal ID of the pedestrian terminal A2 are set in the destination ID included in the normal transmission b, the packet signal by the normal transmission b is the pedestrian terminal A1 and It is analyzed only by the pedestrian terminal A2. Since the action content included in the packet signal is set to vibration, the pedestrian terminal A1 and the pedestrian terminal A2 vibrate to warn the pedestrian A and the pedestrian B of the start of the vehicle A. Thereafter, when the vehicle A moves a predetermined distance, the processing unit 14 ends the proximity search service. The fact that the vehicle A has moved a predetermined distance indicates that the driver has started after confirming safety, and indicates that the proximity search service may be terminated. Note that the movement of the vehicle A by a predetermined distance can be determined from the status information acquired by the status information acquisition unit 15 from a speedometer or the like.

  As described above, the proximity search service can be provided using the communication system using the vehicle-mounted device and the pedestrian terminal according to the present embodiment. According to the neighborhood search service, the driver can accurately grasp the situation around the vehicle. That is, when the pedestrian terminal that has received the search signal is switched to short-distance transmission, only the presence of a pedestrian located in a suitable range (radius 5 to 10 m in the present embodiment) centered on the vehicle can be grasped. In addition, since the number of persons can be accurately grasped, it is possible to accurately recognize the presence of a pedestrian in a blind spot other than the pedestrian that the driver can see. On the other hand, when the pedestrian terminal remains in normal transmission, a warning is issued even if there is a pedestrian in a position that does not affect safety, which hinders smooth driving.

  Moreover, danger can be notified to a pedestrian by transmitting an action instruction signal from the vehicle-mounted device to the pedestrian terminal. Further, by not including the position signal in the presence signal of the pedestrian terminal, a position detection system such as GPS is not required, and the cost, size, weight, and power consumption of the pedestrian terminal can be reduced. .

  FIG. 7 is a diagram for explaining an outline of a waiting service application (hereinafter simply referred to as a waiting service) by the communication system according to the embodiment of the present invention. As a premise for using the waiting service, the vehicle-mounted device of the vehicle and the pedestrian terminal held by the pedestrian must be paired between the vehicle to be waited for and the pedestrian. More specifically, the vehicle-mounted device ID of the vehicle-mounted device and the pedestrian terminal ID of the pedestrian terminal must be held mutually.

  In FIG. 7, the vehicle-mounted device of the vehicle 100 is paired with the pedestrian terminal held by the first pedestrian 201, but is not paired with the pedestrian terminal held by the second pedestrian 202. Is drawn. The first area An1 indicates the radio wave range during normal transmission of the pedestrian terminal held by the first pedestrian 201.

  When using the queuing service, the search signal generation unit 141 of the on-vehicle device includes at least the on-vehicle device ID indicating the transmission source, the pedestrian terminal ID of the paired pedestrian terminal, and information indicating that the signal is related to the queuing service. Is generated. The search signal is stored in the application data area of the packet signal, and after the header and footer of each layer are added, it is broadcast from the RF unit 12 via the antenna 11. The search signal analysis unit 242 of the pedestrian terminal analyzes the search signal included in the packet signal, and when the vehicle-mounted device ID of the paired vehicle-mounted device is included, notifies the presence signal generation unit 241 to that effect. .

  The presence signal generation unit 241 generates a presence signal including at least a pedestrian terminal ID indicating a transmission source, a paired vehicle-mounted device ID, and a transmission mode. The presence signal is stored in the application data area of the packet signal, and after the header and footer of each layer are added, the presence signal is broadcast from the RF unit 22 via the antenna 21. In the present embodiment, normal transmission and short-distance transmission are alternately reported.

  FIG. 8 is a diagram for explaining a specific example 1 of the waiting service by the communication system according to the embodiment of the present invention. FIG. 8 shows signal exchange between the paired vehicle-mounted device and the pedestrian terminal. When the driver of the vehicle equipped with the onboard device instructs the start of the waiting service from the user interface 16, the waiting service is activated on the onboard device. The search signal generation unit 141 of the on-vehicle device generates a search signal, and a packet signal including the search signal is notified by normal transmission. When the distance to the paired pedestrian terminal exceeds several hundreds of meters, a response signal from the pedestrian terminal cannot be received. The vehicle-mounted device continues to notify by normal transmission of the packet signal. When the distance to the paired pedestrian terminal is less than several hundred meters (that is, within the normal signal reachable range), the pedestrian terminal can receive the packet signal. When the pedestrian terminal receives the packet signal, the pedestrian terminal notifies the packet signal including the presence signal by normal transmission.

  Along with the notification by the normal transmission, the action execution unit 244 of the pedestrian terminal may cause the user interface 25 to execute a predetermined action. For example, “You will be picked up soon” may be output as a voice. Thereby, the pedestrian holding the said pedestrian terminal can recognize that the pick-up has come near.

  When the vehicle-mounted device receives a packet signal including a presence signal notified by normal transmission from the pedestrian terminal, a notification information generation unit (not shown) of the vehicle-mounted device indicates that a person waiting for pick-up is nearby. A message may be generated and notified from the user interface 16.

  The pedestrian terminal notifies the packet signal including the presence signal by normal transmission, and then notifies the same packet signal by short-range transmission. The content of the transmission mode included in the presence signal is different. Hereinafter, the vehicle-mounted device notifies a packet signal including a search signal by normal transmission, and the pedestrian terminal performs both notification by normal transmission of a packet signal including a presence signal and notification by short-range transmission. When the vehicle-mounted device can receive a packet signal notified from the pedestrian terminal by short-range transmission, the distance between the vehicle-mounted device and the pedestrian terminal is less than 5 to 10 m (that is, within the short-range signal reachable range). They can see each other to show that they are. Therefore, the processing unit 14 of the vehicle-mounted device ends the waiting service. Note that the waiting service may be terminated due to the door opening, instead of receiving the packet signal notified by the short-distance transmission.

  FIG. 9A shows a data structure example of normal transmission of the vehicle-mounted device shown in FIG. FIG. 9B shows a data structure example of normal transmission of the pedestrian terminal shown in FIG. FIG. 9C shows a data structure example of short-distance transmission of the pedestrian terminal shown in FIG. In the data structure example of normal transmission shown in FIG. 9A, “service type”, “transmission mode”, “source ID”, and “destination ID” are defined as items, and the contents are “wait (request)”. ) ”,“ Normal ”,“ vehicle equipment ID ”, and“ pedestrian terminal ID ”. This pedestrian terminal ID is a pedestrian terminal ID of a paired pedestrian terminal. In the data structure example of normal transmission shown in FIG. 9B, “service type”, “transmission mode”, “source ID”, and “destination ID” are defined as items, and the contents are “waiting (response) ) ”,“ Normal ”,“ pedestrian terminal ID ”, and“ vehicle equipment ID ”. This onboard equipment ID is the onboard equipment ID that is paired. In the short-range transmission data structure example shown in FIG. 9C, “service type”, “transmission mode”, “transmission source ID”, and “destination ID” are defined as items. Response) ”,“ Short distance ”,“ Pedestrian terminal ID ”, and“ Onboard equipment ID ”are set. This onboard equipment ID is the onboard equipment ID of the onboard equipment which is paired.

  In Specific Example 1 shown in FIG. 8 described above, whether or not the pedestrian terminal exists at a short distance is determined based on whether or not the vehicle-mounted device can receive the packet signal notified from the pedestrian terminal by the short distance transmission. . In this regard, the vehicle-mounted device may estimate the distance between the vehicle-mounted device and the pedestrian terminal from the received signal strength (RSSI) received from the pedestrian terminal through normal transmission.

  FIG. 10A is a diagram for explaining a first method for estimating the distance between the vehicle-mounted device and the pedestrian terminal. The first method is the method employed in the first specific example shown in FIG. The pedestrian terminal transmits a packet signal including a presence signal by short-range communication. For example, the packet signal is transmitted with a low power radio wave or a weak radio wave. The in-vehicle device determines that the pedestrian terminal exists in the vicinity when the packet signal transmitted from the pedestrian terminal by the short-range communication can be received, and determines that the pedestrian terminal does not exist in the vicinity when the packet signal cannot be received. When a packet signal is transmitted from a pedestrian terminal with a radio field intensity having a radius of 5 to 10 m as a reception area, and the in-vehicle device can receive the packet signal, the pedestrian within a radius of 5 to 10 m from the on-vehicle device It can be determined that the terminal exists.

  FIG. 10B is a diagram for explaining a second method for estimating the distance between the vehicle-mounted device and the pedestrian terminal. The pedestrian terminal transmits a packet signal including a presence signal through normal communication. In addition, you may transmit with transmission power higher than the transmission power of normal communication. In this case, the transmission distance becomes longer, and the signal reaches a farther vehicle-mounted device. The vehicle-mounted device receives a packet signal transmitted from the pedestrian terminal through normal communication. At that time, the reception intensity is detected. This reception intensity is detected by the RF unit 12 and output to the distance calculation unit 144 of the processing unit 14.

  The distance calculation unit 144 compares the reception strength with the threshold value, and determines that the reception strength is “strong” when the reception strength exceeds the threshold value, and determines that the reception strength is “weak” when the reception strength does not exceed the threshold value. When the reception intensity is “strong”, it is determined that the pedestrian terminal exists in the vicinity, and when the reception intensity is “weak”, it is determined that the pedestrian terminal does not exist in the vicinity.

  A plurality of threshold values may be set. For example, when two threshold values are set, the distance calculation unit 144 compares the reception intensity with the first threshold value and the second threshold value, and when the reception intensity exceeds the first threshold value, the reception intensity is “strong”. The received strength is determined to be “medium” when it is between the first threshold and the second threshold, and the received strength is determined to be “weak” when the second threshold is not exceeded. As a result, the distance between the vehicle-mounted device and the pedestrian terminal can be classified into “near”, “middle”, and “far”.

  The distance calculation unit 144 may convert the reception intensity detected by the RF unit 12 into a distance using a reception intensity / distance conversion formula or a reception intensity / distance conversion table.

  FIG. 11 is a diagram for explaining a specific example 2 of the waiting service by the communication system according to the embodiment of the present invention. In specific example 2, the second method described above is employed. FIG. 11 shows signal exchange between the paired vehicle-mounted device and the pedestrian terminal. When the driver of the vehicle equipped with the onboard device instructs the start of the waiting service from the user interface 16, the waiting service is activated on the onboard device. The search signal generation unit 141 of the on-vehicle device generates a search signal, and a packet signal including the search signal is notified by normal transmission. When the distance to the paired pedestrian terminal exceeds several hundreds of meters, a response signal from the pedestrian terminal cannot be received. The vehicle-mounted device continues to notify by normal transmission of the packet signal. When the distance to the paired pedestrian terminal is less than several hundred meters (that is, within the normal signal reachable range), the pedestrian terminal can receive the packet signal. When the pedestrian terminal receives the packet signal, the pedestrian terminal notifies the packet signal including the presence signal by normal transmission. In the second specific example, unlike the first specific example, the pedestrian terminal does not notify the packet signal by short-range transmission.

  Hereinafter, the vehicle-mounted device notifies the packet signal including the search signal by normal transmission, and the pedestrian terminal also notifies the packet signal including the presence signal by normal transmission. The distance calculation unit 144 of the in-vehicle device calculates the distance from the pedestrian terminal based on the reception intensity of the packet signal notified from the pedestrian terminal. The calculated distance is notified from the user interface 16. As described above, this distance may be defined by an intuitive classification such as “near”, “middle”, and “far”, or may be defined by a specific numerical value such as “100 m”. As a result, the driver can recognize how far the meeting partner is from the vehicle 100.

  When the calculated distance is “near” or less than a set distance (for example, 5 m), the processing unit 14 ends the waiting service because there is a high possibility that they can see each other. Specifically, the notification of the packet signal including the search signal from the in-vehicle device is terminated. In the second specific example, the pedestrian terminal does not need to include the transmission power control unit 245. Therefore, a waiting service can be realized even between a simple pedestrian terminal that does not include the transmission power control unit 245 and the vehicle-mounted device.

  As described above, the meeting service can be provided using the communication system using the vehicle-mounted device and the pedestrian terminal according to the present embodiment. According to the meeting service, even if the distance between the pedestrian and the vehicle driver who are waiting is not visible, the distance between the two approaches (in this embodiment, the distance approaches less than several hundred meters). , Can recognize that they are close to each other. In particular, when a pedestrian waiting to be picked up is a child, a sense of security can be given as soon as possible by recognizing that the pedestrian is approaching as soon as possible.

  In the above, it demonstrated based on the Example of this invention. 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 the above-described embodiment, the vehicle-mounted device does not detect the direction in which the pedestrian terminal is located. However, the walking device transmits radio waves by configuring the antenna 11 with a directional antenna (for example, an adaptive array antenna). The direction in which the person terminal is located can be detected. In this case, not only the number of pedestrians but also information regarding the position of each pedestrian can be notified to the user interface 16.

  FIG. 12 is a diagram for explaining a first search method using directivity. The search device is a device that transmits a packet signal including a search signal. In the example of the proximity search service and the waiting service described above, the search device is an in-vehicle device. In this regard, the search device may be a pedestrian terminal. In a parked vehicle search service to be described later, a pedestrian terminal transmits a packet signal including a search signal. The search target device is a pedestrian terminal when the search device is a vehicle-mounted device, and is a vehicle-mounted device when the search device is a pedestrian terminal.

  First, the search device transmits a packet signal including a search signal with directivity (S11). The searched device receives the packet signal (S12). The searched device detects the reception intensity of the packet signal (S13). Assuming that the distance between the search device and the search target device is constant, the received intensity increases as the position of the search target device is closer to the direction of the radio wave radiated from the search device (hereinafter referred to as the radiation direction). It gets weaker as you leave.

  The searched device transmits a packet signal including a response signal including the reception intensity (S14). The searching device receives the packet signal (S15). The searching device extracts the received intensity from the received packet signal, and estimates the direction or direction in which the searched device exists from the received intensity (S16). Specifically, when the reception intensity is weak, it is estimated that the searched device exists in the direction opposite to the radiation direction, and when the reception intensity is strong, it is estimated that the searched device exists in the emission direction.

  FIG. 13 is a diagram for explaining a second search method using directivity. The search device is a device that transmits a packet signal including a search signal. First, the search device transmits a packet signal including a search signal omnidirectionally (S21). The searched device receives the packet signal (S22). The searched device transmits a packet signal including a response signal (S23). The search device receives the packet signal with the directional antenna (S24). Upon reception, the directivity of the received radio wave is detected. The searching device infers the direction in which the searched device exists from the reception status of the directional antenna (S25). For example, when an adaptive array antenna is used, the reception strength of each of the plurality of antennas is detected, and the direction in which the antenna with the strongest reception strength is located is estimated as the direction in which the search target device exists.

  In the first search method and the second search method, the search device needs to have a directional antenna, and the searched device need not have a directional antenna. When the search device does not include the directional antenna and the search target device includes the directional antenna, the search target device receives the received radio wave when receiving the packet signal including the search signal transmitted from the search device. The direction in which the search device exists is inferred from the directivity of. The searched device transmits a packet signal including a response signal including the direction.

  Hereinafter, application examples of the first search method will be described. In this application example, the search device is an in-vehicle device, and the search target device is a pedestrian terminal. It is assumed that the vehicle-mounted device and the pedestrian terminal hold both pieces of identification information (specifically, the vehicle-mounted device ID and the pedestrian terminal ID). That is, it is assumed that both are paired. In this application example, the driver of the vehicle on which the vehicle-mounted device is mounted searches for a pedestrian holding the pedestrian terminal. For example, when the driver of the vehicle equipped with the vehicle-mounted device and the pedestrian holding the pedestrian terminal are waiting, or when the pedestrian holding the pedestrian terminal is missing or lost Is applicable.

  The vehicle-mounted device transmits a search signal including its own vehicle-mounted device ID and the pedestrian terminal ID of the paired pedestrian terminal with directivity. When the paired pedestrian terminal receives the search signal, it transmits a response signal including the reception intensity of the search signal in addition to its own pedestrian terminal ID and the paired onboard unit ID. To do. The vehicle-mounted device repeatedly transmits the search signal while changing the radiation direction at regular time intervals. The pedestrian terminal transmits the response signal each time it receives a search signal.

  The vehicle-mounted device receives each response signal and extracts each received intensity. The in-vehicle device can specify the direction in which the pedestrian terminal exists by specifying in which radiation direction the response signal including the strongest reception intensity is received when the search signal is transmitted. Further, by continuously receiving the response signal including the reception intensity, it is possible to recognize whether the pedestrian terminal is approaching or moving away. These pieces of information are displayed on the user interface 16 (for example, the display unit of the car navigation device). Also, audio is output from the user interface 16 (for example, an audio output unit of a car navigation device). For example, a louder buzzer sound may be generated as the reception intensity increases.

  Next, an application example of the second search method will be described. In this application example, the search device is a pedestrian terminal, and the search target device is a vehicle-mounted device. Even in this application example, it is assumed that the vehicle-mounted device and the pedestrian terminal are paired. This application example is an example in which a pedestrian holding a pedestrian terminal searches for a vehicle equipped with a vehicle-mounted device. For example, it corresponds to the case of searching for own vehicle in a parking lot.

  The pedestrian terminal transmits a search signal including its own pedestrian terminal ID and the on-vehicle device ID of the on-vehicle device paired. When receiving the search signal, the paired vehicle-mounted device transmits a response signal including its own vehicle-mounted device ID and the pedestrian terminal ID of the paired pedestrian terminal. A pedestrian can transmit search signals in various radial directions intended by the pedestrian by changing the direction of the pedestrian terminal in various directions. As a result, a search signal having directivity is generated in a pseudo manner. The on-vehicle device transmits the response signal every time a search signal is received.

  The pedestrian terminal receives each response signal and detects the reception intensity of each response signal. The pedestrian terminal specifies the direction in which the vehicle exists based on the received intensity. For example, in a three-dimensional parking lot, the floor on which the vehicle is parked can be specified based on the difference in reception intensity. After the pedestrian moves to the specified floor, the direction of the parking position on the floor can be specified by the difference in reception intensity. The directivity of the antenna that receives the response signal may be set so as to be switchable between all directions and a specific direction. When the pedestrian specifies the floor, the pedestrian sets it in all directions, sets the specific direction after moving to the specified floor. The detected reception intensity and / or direction in which the vehicle is present is displayed on the user interface 25 or is output as audio from the user interface 25. For example, a louder buzzer sound may be generated as the reception intensity increases. The pedestrian confirms the level of the buzzer sound while changing the direction of the pedestrian terminal, and moves in a direction in which the buzzer sound is large.

  Moreover, in order to pinpoint the floor where the vehicle is parked more accurately in the multilevel parking lot, a simple vehicle-mounted device may be installed at the pedestrian entrance of each floor. When the pedestrian who gets out of the vehicle passes through the pedestrian entrance of the parked floor, the in-vehicle device and the pedestrian terminal are paired. When a pedestrian returns to the multi-story parking lot, a search signal is transmitted from the pedestrian terminal, and a response signal is received from the paired on-board device to identify which floor on-board device is paired with it can. The pedestrian terminal may be specified by the reception intensity of the response signal, or may be specified by the information when the floor identification information is included in the response signal.

  Next, another application example of the second search method will be described. In this application example, the search device is an in-vehicle device, and the search target device is a pedestrian terminal. Even in this application example, it is assumed that the vehicle-mounted device and the pedestrian terminal are paired. This application example is an example of confirming the position of a family (especially a child) or a pet who got off first when entering the garage.

  The neighborhood search service at the time of entering the garage is triggered when the vehicle moves backward. When the neighborhood search service is activated at the time of entering the garage, the vehicle-mounted device transmits a search signal including its vehicle-mounted device ID and a pedestrian terminal ID of a paired pedestrian terminal held by a child or the like. When the paired pedestrian terminal receives the search signal, the paired pedestrian terminal transmits a response signal including its own pedestrian terminal ID and the onboard unit ID of the paired onboard unit.

  The vehicle-mounted device receives the response signal from the pedestrian terminal and detects the reception intensity of the response signal. The vehicle-mounted device determines that there is a family or a pet in the vicinity of the vehicle when the reception intensity exceeds the threshold value. Further, the direction in which the family or the pet is present can be specified from the received intensity. These pieces of information are displayed on the user interface 16 (for example, the display unit of the car navigation device). Also, audio is output from the user interface 16 (for example, an audio output unit of a car navigation device). The above processing is continuously executed until the neighborhood search service at the time of entering the garage is completed. The neighborhood search service at the time of entering the garage is terminated by stopping the engine of the vehicle.

  In the above-described embodiment, the transmission mode of the pedestrian terminal is set to two types of normal transmission and short-distance transmission for the sake of simplification. However, the configuration may be such that a packet signal can be transmitted with arbitrary transmission power. . The transmission power control unit 245 adjusts the transmission power, so that the RF unit 12 can transmit a packet signal with an arbitrary radio wave intensity. That is, the transmission power control unit 245 can adjust the reception range of radio waves transmitted from the RF unit 12 via the antenna 11.

  The on-vehicle device distance calculation unit 144 can calculate the estimated distance between the pedestrian terminal and the on-vehicle device. When the pedestrian terminal receives the packet signal including the estimated distance, the transmission power control unit 245 can adjust the transmission power according to the estimated distance. For example, in the proximity search service, the transmission power control unit 245 may adjust the transmission power corresponding to the estimated distance to the vehicle-mounted device. In the meeting service, the transmission power control unit 245 may decrease the transmission power step by step by continuously receiving the estimated distance calculated by the distance calculation unit 144 by the pedestrian terminal. That is, as the distance between the vehicle-mounted device and the pedestrian terminal approaches, the transmission power may be adjusted according to the distance. According to these processes, more optimized transmission of the presence signal can be realized.

  In the embodiment described above, the pedestrian terminal is a dedicated terminal. However, the function of the pedestrian terminal described above may be mounted on an existing mobile phone or smartphone.

  In the above-described embodiment, a four-wheeled vehicle has been described as an example of the vehicle 100 on which the wireless device 10 is mounted. However, a two-wheeled vehicle such as a motorcycle or a bicycle may be used. Moreover, although the example where a person holds the wireless device 20 has been described, an animal such as a dog or a cat may be worn.

  DESCRIPTION OF SYMBOLS 10 Radio apparatus, 11 Antenna, 12 RF part, 13 Modulation / demodulation part, 14 Processing part, 141 Search signal generation part, 142 Existence signal analysis part, 143 Action instruction | indication signal generation part, 144 Distance calculation part, 15 Status information acquisition part, 16 User interface, 17 control unit, 20 wireless device, 21 antenna, 22 RF unit, 23 modulation / demodulation unit, 24 processing unit, 241 presence signal generation unit, 242 search signal analysis unit, 243 action instruction signal analysis unit, 244 action execution unit, 245 transmission power control unit, 25 user interface, 26 control unit, 100 vehicle, 201 first pedestrian, 202 second pedestrian, 203 third pedestrian, 204 fourth pedestrian.

Claims (6)

An in-vehicle device to be mounted on a vehicle ,
A transmission unit for transmitting a search signal for searching for a mobile terminal device possessed by a person or animal present around the vehicle at a transmission power corresponding to the transmission power of the normal transmission mode of the mobile terminal device ;
A receiving unit that receives a presence signal indicating the presence of a person or an animal, which is transmitted in a short-distance transmission mode having a transmission power lower than that of the normal transmission mode, from a mobile terminal device that has received the search signal transmitted from the transmission unit. When,
Based on the presence signal, a notification unit for notifying a person in the vehicle of the presence of a person or an animal around the vehicle;
A vehicle-mounted device comprising: The presence signal received by the receiving unit includes an identification signal that identifies the mobile terminal device that has received the search signal, and identification information that identifies the vehicle-mounted device ,
The notification unit counts the number of identification signals that identify the mobile terminal device that has received the search signal, and notifies the number of people or animals around the vehicle to the people in the vehicle. The vehicle-mounted device according to claim 1. The vehicle-mounted device according to claim 1, wherein the presence signal received by the receiving unit has a reception range narrower than a reception range of the search signal. The in- vehicle device according to claim 1, wherein the transmission unit transmits the search signal when the vehicle is predicted to change from a stopped state to a traveling state. A mobile terminal device to be carried by a person or animal,
A transmission unit that transmits a presence signal indicating the presence of a person or animal in a short-distance transmission mode in which transmission power is lower than that in the normal transmission mode ;
A receiving unit that receives a search signal for searching for a mobile terminal device possessed by a person or an animal, which is transmitted from a vehicle-mounted device mounted on a vehicle at a transmission power corresponding to the transmission power of the normal transmission mode ; Prepared,
The receiving unit receives a search signal including identification information for identifying the on - vehicle device from the on- vehicle device ,
The said transmission part transmits the presence signal containing the identification information which identifies the said onboard equipment, and the identification information which identifies this mobile terminal device in the said short distance transmission mode, The mobile terminal device characterized by the above-mentioned . The mobile terminal apparatus according to claim 5, wherein the presence signal transmitted by the transmission unit has a transmission distance shorter than a transmission distance of the search signal.

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