WO2013094187A1 - Appareil sans fil - Google Patents

Appareil sans fil Download PDF

Info

Publication number
WO2013094187A1
WO2013094187A1 PCT/JP2012/008090 JP2012008090W WO2013094187A1 WO 2013094187 A1 WO2013094187 A1 WO 2013094187A1 JP 2012008090 W JP2012008090 W JP 2012008090W WO 2013094187 A1 WO2013094187 A1 WO 2013094187A1
Authority
WO
WIPO (PCT)
Prior art keywords
vehicle
unit
area
terminal device
wireless device
Prior art date
Application number
PCT/JP2012/008090
Other languages
English (en)
Japanese (ja)
Inventor
哲一 江見
真琴 永井
児島 則章
Original Assignee
三洋電機株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP2011279459A external-priority patent/JP2015043477A/ja
Priority claimed from JP2011279506A external-priority patent/JP2015043478A/ja
Application filed by 三洋電機株式会社 filed Critical 三洋電機株式会社
Publication of WO2013094187A1 publication Critical patent/WO2013094187A1/fr

Links

Images

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W52/00Power management, e.g. TPC [Transmission Power Control], power saving or power classes
    • H04W52/04TPC
    • H04W52/18TPC being performed according to specific parameters
    • H04W52/28TPC being performed according to specific parameters using user profile, e.g. mobile speed, priority or network state, e.g. standby, idle or non transmission
    • H04W52/283Power depending on the position of the mobile
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W52/00Power management, e.g. TPC [Transmission Power Control], power saving or power classes
    • H04W52/02Power saving arrangements
    • H04W52/0209Power saving arrangements in terminal devices
    • H04W52/0251Power saving arrangements in terminal devices using monitoring of local events, e.g. events related to user activity
    • H04W52/0254Power saving arrangements in terminal devices using monitoring of local events, e.g. events related to user activity detecting a user operation or a tactile contact or a motion of the device
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02DCLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
    • Y02D30/00Reducing energy consumption in communication networks
    • Y02D30/70Reducing energy consumption in communication networks in wireless communication networks

Definitions

  • the present invention relates to communication technology, and more particularly, to a wireless device that transmits and receives a signal including predetermined information.
  • Road-to-vehicle communication is being studied to prevent collisions at intersections.
  • 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.
  • installation of a roadside machine will become unnecessary.
  • 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 each enter the intersection. (See, for example, Patent Document 1).
  • the present invention has been made in view of such circumstances, and an object thereof is to provide a wireless device suitable for a communication environment.
  • a wireless device that performs communication with another wireless device, and includes a communication unit that performs transmission processing and reception processing, and the wireless device includes: An estimation unit that estimates whether the vehicle exists inside the vehicle or outside the vehicle. When the estimation unit estimates that the wireless device is present in the vehicle, the communication unit transmits a signal with lower transmission power than when the wireless device exists outside the vehicle.
  • a wireless device suitable for a communication environment can be provided.
  • FIGS. 3A to 3D are diagrams showing frame formats defined in the communication system of FIG.
  • FIGS. 4A and 4B are diagrams illustrating the configuration of the priority area and the general area.
  • FIGS. 5 (a)-(b) are diagrams showing the configuration of the subframes of FIGS. 3 (a)-(d).
  • FIGS. 6A and 6B 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 mounted in the vehicle of FIG.
  • CSMA / CA Carrier Sense Multiple Access Avididance
  • 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.
  • 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 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 (hereinafter referred to as “road vehicle transmission period”) for the base station apparatus to broadcast the packet signal.
  • 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.
  • the collision probability of packet signals between them is reduced. That is, when the terminal device recognizes the content of the control information, interference between road-vehicle communication and vehicle-to-vehicle communication is reduced.
  • the area where the terminal device performing inter-vehicle communication is mainly classified into three types.
  • first area One is an area formed around the base station apparatus (hereinafter referred to as “first area”), and the other is an area formed outside the first area (hereinafter referred to as “second area”). Another one is an area formed outside the second area (hereinafter referred to as “outside the second area”).
  • first area and second area the terminal device can receive the packet signal from the base station apparatus with a certain quality, whereas outside the second area, the packet signal from the base station apparatus is received.
  • the terminal device cannot receive with a certain quality.
  • the first area is formed closer to the center of the intersection than the second area.
  • the following two situations are assumed depending on the shape of the intersection.
  • the packet signal from the terminal device mounted on the vehicle can be said to be important information from the viewpoint of suppressing collision accidents.
  • the second situation is that the vehicle in the first area exists near the intersection, so the packet signal from the terminal device mounted on the vehicle is important information from the point of suppression of collision accidents. This is the case.
  • it is required to set the priority according to the position where the packet signal should be transmitted. If the driver can recognize what priority is set in the area, it can be reflected in the driving. For example, if it is known that the vehicle is located in a high priority area, the possibility of a collision accident increases, so the driver can drive more carefully. For this reason, it is desired that the driver recognize what kind of priority exists in the set area.
  • a period for vehicle-to-vehicle communication (hereinafter referred to as “vehicle transmission period”) is formed by time division multiplexing of a priority period and a general period.
  • the priority period is formed by a plurality of slots, and the terminal device broadcasts the packet signal by any of the plurality of slots.
  • the general period has a predetermined period, and the terminal apparatus broadcasts a packet signal by the CSMA method during the general period.
  • the terminal device existing outside the second area transmits a packet signal by the CSMA method regardless of the frame configuration.
  • the terminal apparatus existing in the second area is made to use the priority period
  • the terminal apparatus existing first is made to use the general period.
  • the terminal apparatus existing in the first area uses the priority period
  • the terminal apparatus existing in the second area uses the general period.
  • the terminal device mounted on the vehicle it is determined in which area the terminal device mounted on the vehicle is present. It is preferable for the driver to be able to recognize which area is present.
  • the driver can drive more carefully than before, if he / she recognizes that it is in the priority area. That is, the driver can be alerted.
  • the terminal device notifies the driver of the area that currently exists, thereby allowing the driver to recognize that the area has changed.
  • 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. , The eighth vehicle 12h, and the network 202.
  • Each vehicle 12 is equipped with a terminal device (not shown).
  • the first area 210 is formed around the base station apparatus 10, the second area 212 is formed outside the first area 210, and the second outside area 214 is formed outside the second area 212. ing.
  • 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 central portion.
  • 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”
  • 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
  • the third vehicle 12c and the fourth vehicle 12d are traveling from right to left
  • the fifth vehicle 12e and the sixth vehicle 12f are traveling from the top to the bottom
  • the seventh vehicle 12g and the eighth vehicle 12h are traveling from the bottom to the top.
  • the communication system 100 arranges the base station apparatus 10 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).
  • 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.
  • a packet signal containing data such as traffic jam information and construction information (hereinafter referred to as “RSU packet signal”) and a packet signal including data relating to each slot (hereinafter referred to as “control packet signal”) are separately provided. Is generated.
  • the RSU packet signal and the control packet signal are collectively referred to as “packet signal”.
  • a first area 210 and a second area 212 are formed around the communication system 100 according to the reception status when the terminal apparatus receives a packet signal from the base station apparatus 10.
  • a first area 210 is formed in the vicinity of the base station apparatus 10 as an area having a relatively good reception status. It can be said that the first area 210 is formed near the central portion of the intersection.
  • the second area 212 is formed outside the first area 210 as a region where the reception situation is worse than that of the first area 210.
  • an area outside the second area 214 is formed as an area where the reception status is worse than that in the second area 212. Note that the packet signal error rate and received power are used as the reception status.
  • the packet signal from the base station apparatus 10 includes two types of control information, one is information on the set road and vehicle transmission period (hereinafter referred to as “basic part”), and the other is Information on the set priority period (hereinafter referred to as “extended portion”).
  • the terminal device generates a frame based on the basic part 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. Further, the terminal device receives the packet signal broadcasted by the base station device 10, and based on the reception status of the received packet signal and the extended portion, the first area 210, the second area 212, and the second area outside It is estimated in which of 214.
  • the extended portion included in the packet signal from the base station apparatus 10 includes information indicating the correspondence between the area and the vehicle transmission period (hereinafter referred to as “priority area identifier”).
  • the information indicating the correspondence between the area and the vehicle transmission period can be said to be information indicating whether the priority period should be used in either the first area 210 or the second area 212.
  • the first arrangement and the second arrangement are defined. In the first arrangement, the general period is used in the first area 210 and the priority period is used in the second area 212. On the other hand, in the second arrangement, the priority period is used in the first area 210 and the general period is used in the second area 212.
  • the terminal device When the priority area identifier indicates the first arrangement and exists in the first area 210, the terminal device broadcasts the packet signal by carrier sense in the general period, and when the priority area identifier exists in the second area 212, priority is given. The packet signal is broadcast in any slot included in the period. When the priority area identifier indicates the second arrangement and exists in the first area 210, the terminal device broadcasts the packet signal in any slot included in the priority period and exists in the second area 212. When doing so, the packet signal is broadcast by carrier sense in the general period.
  • TDMA is executed in the priority period
  • CSMA / CA is executed in the general period.
  • the terminal apparatus also selects subframes having the same relative timing in the next frame.
  • the terminal device selects slots having the same relative timing in the next frame.
  • the terminal device acquires data and stores the data in a packet signal.
  • the data includes, for example, information related to the location.
  • 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.
  • the terminal device broadcasts the packet signal by executing CSMA / CA regardless of the frame configuration.
  • 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 80.
  • the processing unit 26 includes a frame definition unit 40, a selection unit 42, a detection unit 44, a generation unit 46, and a setting unit 48.
  • 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.
  • the RF unit 22 also includes an LNA (Low Noise Amplifier), a mixer, an AGC, and an A / D conversion unit.
  • LNA Low Noise Amplifier
  • the RF unit 22 performs frequency conversion on the baseband packet signal input from the modem unit 24 as a transmission process, and generates 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.
  • PA Power Amplifier
  • 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.
  • the modem unit 24 since the communication system 100 corresponds to the OFDM (Orthogonal Frequency Division Multiplexing) modulation method, the modem unit 24 also executes FFT (Fast Fourier Transform) as reception processing and IFFT (Inverse TransFastFast) 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.
  • 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.
  • the frame defining unit 40 may detect the control information from the demodulation result and generate a frame based on the detected control information.
  • FIGS. 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 unit 42 selects a subframe in which a road and vehicle transmission period is to be set from among a plurality of subframes included in the 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 extraction method will be described later. The selection unit 42 identifies the subframe that has not received the demodulation result by specifying the subframe that has received the demodulation result.
  • the selection unit 42 selects one subframe at random.
  • the selection unit 42 acquires reception power corresponding to the demodulation result, and gives priority to subframes with low reception power.
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • the selection unit 42 outputs the selected subframe number to the detection unit 44 and the generation unit 46.
  • the setting unit 48 has an interface for receiving instructions from the business operator, and receives parameter setting instructions via the interface.
  • the interface is a button, and the setting unit 48 receives a parameter setting instruction by inputting to the button.
  • the interface may be a connection terminal with a network communication unit 80 described later.
  • the setting unit 48 receives a parameter setting instruction via the network communication unit 80, the network 202 (not shown), and the PC.
  • the parameter setting instruction is whether to use the first arrangement or the second arrangement.
  • the setting unit 48 outputs the received setting instruction to the generation unit 46.
  • FIG. 4A are diagrams for explaining the configuration of the priority area and the general area.
  • the first area 210, the second area 212, and the second outside area 214 shown in these figures are the same as those in FIG. FIG. 4A corresponds to the first arrangement.
  • a first area 210 around the base station device 10 (not shown) is set as a general area.
  • the general area is an area where the general period should be used. Therefore, the terminal device 14 existing in the general area can report the packet signal in the general period.
  • a second area surrounding the first area 210 is set as a priority area.
  • the priority area is an area where the priority period should be used. Therefore, the terminal device 14 existing in the priority area can broadcast the packet signal in each slot forming the priority period.
  • FIG. 4B corresponds to the second arrangement.
  • the first area 210 is set as the priority period
  • the second area 212 is set as the general period. Note that the sizes of the first area 210 and the second area 212 may be different between the first arrangement and the second arrangement.
  • FIGS. 5A to 5B show subframe configurations. As illustrated, one subframe is configured in the order of a road and vehicle transmission period, a priority period, and a general period.
  • the base station device 10 broadcasts the packet signal
  • the priority period is formed by time division multiplexing of a plurality of slots
  • the terminal device 14 can broadcast the packet signal in each slot
  • the general period has a predetermined length
  • the terminal device 14 can broadcast the packet signal.
  • the priority period and the general period correspond to the vehicle transmission period shown in FIG.
  • the subframe is configured in the order of the priority period and the general period. At that time, the road and vehicle transmission period is also a priority period.
  • FIG. 5B will be described later. Returning to FIG.
  • the detection unit 44 measures the received power for each slot and also measures the error rate for each slot.
  • An example of the error rate is BER (Bit Error Rate). If the received power is lower than the received power threshold, the detection unit 44 determines that the slot is unused (hereinafter, such a slot is referred to as an “empty slot”). On the other hand, if the received power is equal to or greater than the received power threshold and the error rate is lower than the error rate threshold, the detection unit 44 is in use of the slot (hereinafter referred to as such a slot). It is determined as “used slot”.
  • BER Bit Error Rate
  • the detection unit 44 If the received power is equal to or greater than the threshold for received power and the error rate is equal to or greater than the threshold for error rate, the detection unit 44 has a collision in the slot (hereinafter referred to as such a slot). Are referred to as “collision slots”). The detection unit 44 executes such processing for all slots and outputs the results (hereinafter referred to as “detection results”) to the generation unit 46.
  • the generation unit 46 receives a setting instruction from the setting unit 48, receives a subframe number from the selection unit 42, and receives a detection result from the detection unit 44.
  • the generation unit 46 sets a road and vehicle transmission period in the subframe of the received subframe number, and generates a control packet signal and an RSU packet signal to be notified during the road and vehicle transmission period.
  • FIG. 5B shows the arrangement of packet signals during the road and vehicle transmission period. As illustrated, one control packet signal and 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).
  • FIGS. 6A and 6B show the format of the MAC frame stored in the packet signal defined in the communication system 100.
  • FIG. FIG. 6A shows the format of the MAC frame.
  • “MAC header”, “LLC header”, “message header”, “data payload”, and “FCS” are arranged in order from the top.
  • the packet signal storing the MAC frame corresponds to the control packet signal.
  • the generation unit 46 includes them in the data payload.
  • a packet signal storing such a MAC frame corresponds to an RSU packet signal.
  • the network communication unit 80 is connected to a network 202 (not shown).
  • the packet signal broadcasted in the priority period and the general period also stores the MAC frame shown in FIG.
  • FIG. 6B is a diagram illustrating a configuration of a message header generated by the generation unit 46.
  • the message header includes a basic part and an extended part.
  • the basic part includes “protocol version”, “transmission node type”, “reuse count”, “TSF timer”, “RSU transmission period length”, and the extended part includes “vehicle slot size”, “priority general ratio” ",” Priority general threshold value ",” priority area identifier ".
  • Protocol version indicates the version of the supported 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.
  • 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.
  • the car slot size indicates the size of the slot included in the priority period
  • the priority general ratio indicates the ratio between the priority period and the general period
  • the priority general threshold indicates whether the priority period is used or the general period is used. It is a threshold value for causing the terminal device 14 to select and a threshold value for the received power.
  • the priority area identifier is an identifier for indicating which one of the first arrangement and the second arrangement is used. Here, when the first arrangement is used, that is, when the arrangement of FIG. 4A is used, the priority area identifier is set to “0”. When the second arrangement is used, that is, when the arrangement shown in FIG. 4B is used, the priority area identifier is set to “1”. Thus, the extended portion corresponds to information on the priority period and the general period.
  • the processing unit 26 broadcasts the packet signal to the modem unit 24 and the RF unit 22 during the road and vehicle transmission period. That is, the processing unit 26 broadcasts the control packet signal and the RSU packet signal including the basic part and the extended part in the base station broadcast period.
  • 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 only by hardware, or by a combination of hardware and software.
  • FIG. 7 shows the configuration of the terminal device 14 mounted on the vehicle 12.
  • the terminal device 14 includes an antenna 50, an RF unit 52, a modem unit 54, a processing unit 56, and a control unit 58.
  • the processing unit 56 includes a generation unit 64, a timing identification unit 60, a transfer determination unit 90, a notification unit 70, and an acquisition unit 72.
  • the timing specifying unit 60 includes an extraction unit 66, a selection unit 92, and a carrier sense unit 94.
  • 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 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 apparatuses 14 in the priority period and the general period.
  • the extraction unit 66 specifies the timing of the subframe in which the road-vehicle transmission period is arranged. Further, the extraction unit 66 generates a frame based on the subframe timing and the content of the basic part in 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 thus 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.
  • the extraction unit 66 measures the received power of the packet signal from the base station apparatus 10. Based on the measured received power, the extraction unit 66 estimates whether it exists in the first area 210, the second area 212, or outside the second area 214. For example, the extraction unit 66 stores an area determination threshold value. The area determination threshold corresponds to the above-described priority general threshold. If the received power is larger than the area determination threshold, the extraction unit 66 determines that the first area 210 exists. If the received power is equal to or less than the area determination threshold, the extraction unit 66 determines that the second area 212 exists. When the packet signal from the base station apparatus 10 has not been received, the extraction unit 66 determines that it exists outside the second area 212. Note that the extraction unit 66 may use an error rate instead of the received power, or may use a combination of the received power and the error rate.
  • the extraction unit 66 determines whether the currently existing area is a priority area or a general area based on the estimation result and the priority area identifier. When the priority area identifier is “1”, the extraction unit 66 selects the priority area if it exists in the first area 210, and selects the general area if it exists in the second area 212. On the other hand, when the priority area identifier is “0”, the extraction unit 66 selects the general area if it exists in the first area 210 and selects the priority area if it exists in the second area 212.
  • the extraction unit 66 selects a timing unrelated to the frame configuration.
  • the extraction unit 66 selects a general period when a general area is selected.
  • the extraction unit 66 selects a priority period.
  • the extraction unit 66 outputs the detection result included in the data payload of the control packet signal to the selection unit 92.
  • the extraction unit 66 outputs information on the frame and subframe timing and the vehicle transmission period to the carrier sense unit 94.
  • the extraction unit 66 instructs the carrier sense unit 94 to execute carrier sense.
  • the selection unit 92 receives the detection result from the extraction unit 66. As described above, the detection result indicates whether each of the plurality of slots included in the priority period is an empty slot, a used slot, or a collision slot. The selection unit 92 selects one of the empty slots. If a slot has already been selected, the selection unit 92 continues to select the same slot if the slot is a used slot. On the other hand, when the slot has already been selected, the selection unit 92 newly selects an empty slot if the slot is a collision slot. The selection unit 92 notifies the generation unit 64 of information related to the selected slot as a transmission timing.
  • the carrier sense unit 94 receives information on frame and subframe timing and vehicle transmission period from the extraction unit 66.
  • the carrier sense unit 94 measures the interference power by performing carrier sense in the general period. Further, the carrier sense unit 94 determines the transmission timing in the general period based on the interference power. More specifically, the carrier sense unit 94 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 94 determines the transmission timing.
  • the carrier sense unit 94 determines the transmission timing by executing the CSMA without considering the frame configuration. The carrier sense unit 94 notifies the generation unit 64 of the determined transmission timing.
  • the acquisition unit 72 includes a GPS receiver (not shown), a gyroscope, a vehicle speed sensor, and the like. Based on data supplied from these, the location of the vehicle 12 (not shown), that is, the position of the vehicle 12 on which the terminal device 14 is mounted, the progress The direction, the moving speed, etc. (hereinafter collectively referred to as “position information”) are acquired. The existence position is indicated by latitude and longitude. Since a known technique may be used for these acquisitions, description thereof is omitted here. The acquisition unit 72 outputs the position information to the generation unit 64.
  • the transfer determination unit 90 controls the transfer of the message header.
  • the transfer determining unit 90 extracts a message header from the packet signal.
  • the reuse count is set to “0”.
  • the transfer determining unit 90 selects a message header to be transferred from the extracted message header.
  • the transfer determination unit 90 may generate a new message header by combining the contents included in the plurality of message headers.
  • the transfer determination unit 90 outputs the message header to be selected to the generation unit 64. At that time, the transfer determining unit 90 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 90.
  • the generation unit 64 uses the MAC frame shown in FIGS. 6A to 6B and stores the position information in the data payload.
  • the generation unit 64 generates a packet signal including a MAC frame, and generates the packet signal via the modulation / demodulation unit 54, the RF unit 52, and the antenna 50 at the transmission timing determined by the selection unit 92 or the carrier sense unit 94. Broadcast packet signals.
  • the transmission timing is included in the vehicle transmission period.
  • the notification unit 70 acquires a packet signal from the base station apparatus 10 (not shown) in the road and vehicle transmission period, and acquires a packet signal from another terminal apparatus 14 (not shown) in the vehicle and vehicle transmission period. As a process for the acquired packet signal, the notification unit 70 notifies the driver of the approach of another vehicle 12 (not shown) or the like via a monitor or a speaker in accordance with the content of data stored in the packet signal.
  • the extraction unit 66 identifies either the first area 210, the second area 212, or the second area 214.
  • the first area 210, the second area 212, and the second outside area 214 can be said to be areas having different priorities.
  • the priority of the first area 210 is the highest, and the priority of the second area 212 is the next. High and the priority outside 214 in the second area is low. In this case, it can be said that the priority of each area is defined according to the importance of the signal to be notified.
  • the second area 212 since the first area 210 corresponds to the general area and the second area 212 corresponds to the priority area, the second area 212 has the highest priority, and the first area 210 has the highest priority. Next, the priority of 214 outside the second area is low.
  • the priority for the first area 210 and the second area 212 is determined according to the quality of the received signal.
  • the first area 210 with higher reception quality has a higher priority than the second area 212 with lower reception quality.
  • the second area 212 having a lower reception quality has a higher priority than the first area 210 having a higher reception quality.
  • the priority for the first area 210 and the second area 212 is determined according to the distance to the base station apparatus 10.
  • the first area 210 with a shorter distance has a higher priority than the second area 212 with a longer distance.
  • the second area 212 having a longer distance has a higher priority than the first area 210 having a shorter distance.
  • the extraction unit 66 detects movement to a different area by monitoring an existing area. For example, movement from a priority area to a general area. The reverse movement may be used. Furthermore, the movement may be between the second area 212 and the second area 214, such as between the general area and the second area 214, or between the priority area and the second area 214. .
  • the extraction unit 66 changes the instruction to the selection unit 92 and the carrier sense unit 94. For example, when the movement from the priority area to the general area is detected, the extraction unit 66 changes the communication process defined in the priority area to the communication process defined in the general area. Specifically, the instruction to the selection unit 92 is changed to an instruction to the carrier sense unit 94.
  • the extraction unit 66 When the extraction unit 66 detects a movement between the second area 212 and the second area 214, the extraction unit 66 performs a communication process between the communication process in the second area 212 and the communication process in the second area 214. change.
  • the communication processing in the second area 212 is the use of the priority period by the selection unit 92 or the general period by the carrier sense unit 94. Since these are operations constrained by the frame configuration, it can be said that the operations correspond to the operation timing of the base station apparatus 10.
  • the communication processing outside the second area 214 is an operation that does not depend on the frame configuration by the carrier sense unit 94. This can be said to be an operation unrelated to the operation timing of the base station apparatus 10.
  • the extraction unit 66 notifies the notification unit 70 of the area change by notifying the notification unit 70 of the existing area.
  • the notification unit 70 notifies the driver of the existing area based on the area information received from the extraction unit 66. For example, when the notification unit 70 exists in the priority area, the vehicle in the navigation system is displayed in red. The notification part 70 displays the own vehicle in a navigation system in yellow, when it exists in a general area. When the notification unit 70 exists outside the second area 214, the notification unit 70 displays the host vehicle in the navigation system in blue. In this way, the display color of the host vehicle is changed according to the existing area, which corresponds to changing the notification mode according to the existing area. As a result, the notification unit 70 notifies the area change when the movement is detected. The notification unit 70 may output a warning sound when entering the priority area, or may output a warning by voice. That is, it is only necessary for the driver to be informed that the vehicle has entered the priority area. A similar process may be performed in the movement between the second area 212 and the second area outside 214. The control unit 58 controls the operation of the entire terminal device 14.
  • FIG. 8 is a flowchart showing a procedure for selecting a priority period or a general period in the terminal device 14. If the priority area identifier is “1” (Y in S30) and the received power is larger than the threshold (Y in S32), the extraction unit 66 determines the use of the priority period (S34). If the received power is not greater than the threshold value (N in S32), the extraction unit 66 determines the use of the general period (S36). If the priority area identifier is not “1” (N in S30) and the received power is larger than the threshold value (Y in S38), the extraction unit 66 determines the use of the general period (S40). If the received power is not greater than the threshold (N in S38), the extraction unit 66 determines the use of the priority period (S42).
  • FIG. 9 is a flowchart showing a display procedure in the terminal device 14.
  • the notification part 70 displays the vehicle 12 in red (S62).
  • the notification unit 70 displays the vehicle 12 in yellow (S66).
  • the notification unit 70 displays the vehicle 12 in blue (S68).
  • the first modification of the present invention also relates to a terminal device that broadcasts a packet signal in which position information and the like are stored.
  • the terminal device is mounted on a vehicle.
  • the terminal device is carried by the user and moved. Since such a terminal device is operated by a built-in battery, low power consumption is desired.
  • the terminal device is required to inform the vehicle of the location of the user by transmitting a packet signal.
  • the terminal device is also desired to operate similarly to the terminal device mounted on the vehicle.
  • the terminal device when present outside the vehicle, executes only the transmission process of the packet signal and stops the reception process of the packet signal. On the other hand, when the terminal device is present in the vehicle, the terminal device performs a packet signal transmission process and a reception process.
  • the terminal device is estimated to exist outside the vehicle when operating with the built-in battery, and is estimated to exist within the vehicle when operating with the external power source.
  • the communication system 100 according to the first modification is the same type as that in FIG. 1, and the base station apparatus 10 is the same type as that in FIG. Below, it demonstrates focusing on a difference.
  • FIG. 10 shows a configuration of the terminal device 14 according to the first modification of the present invention.
  • the terminal device 14 includes an antenna 50, an RF unit 52, a modem unit 54, a processing unit 56, a control unit 58, and a connection unit 88.
  • the processing unit 56 includes a transmission processing unit 82, a reception processing unit 84, and an estimation unit 86. Since the antenna 50, the RF unit 52, and the modem unit 54 perform the same operations as those in FIG. 7, the description thereof is omitted here.
  • the transmission processing unit 82 corresponds to a part of the processing unit 56 in FIG. 7 that executes a process for informing a packet signal
  • the reception processing unit 84 includes the packet signal in the processing unit 56 in FIG. This corresponds to the part that executes the process for receiving.
  • the terminal device 14 is configured to be portable by the user, for example, like a mobile phone terminal.
  • connection unit 88 is connected to a power supply terminal provided in the vehicle 12 (not shown).
  • the connection unit 88 receives power supply from the power supply terminal and drives the terminal device 14.
  • the connection unit 88 is not connected to the power supply terminal and does not accept supply of power. At that time, the terminal device 14 is driven by an internal battery (not shown).
  • the estimation part 86 detects whether the connection part 88 is connected to the power supply terminal. Since a known technique may be used for the detection, description thereof is omitted here. When the estimation unit 86 detects that it is connected to the power supply terminal, the estimation unit 86 estimates that it exists in the vehicle 12. When the estimation unit 86 detects that it is not connected to the power supply terminal, the estimation unit 86 estimates that it exists outside the vehicle 12. That is, the estimation unit 86 estimates whether the terminal device 14 exists in the vehicle 12 or outside the vehicle 12. When estimating that the vehicle is present in the vehicle 12, the estimation unit 86 operates the transmission processing unit 82 and the reception processing unit 84 to perform transmission processing and reception processing.
  • the estimation unit 86 estimates that the vehicle exists outside the vehicle 12, the estimation unit 86 stops one of the transmission processing and the reception processing by stopping one of the transmission processing unit 82 and the reception processing unit 84.
  • the estimation unit 86 operates only the transmission processing unit 82 and stops the reception processing unit 84. Note that the reverse may be possible.
  • FIG. 11 is a flowchart showing a processing procedure in the terminal device 14. If it is battery driven (Y of S80), the estimation part 86 will perform a transmission process and will stop a reception process (S82). On the other hand, if the battery is not driven (N in S80), the estimation unit 86 causes the transmission process and the reception process to be executed (S84).
  • the 2nd modification of this invention is related with the terminal device comprised so that a user might move like the 1st modification.
  • the second modification of the present invention is directed to the case where the terminal device is outside the vehicle.
  • the terminal device In the first modification, when the terminal device exists outside the vehicle, one of the transmission process and the reception process is stopped for the purpose of reducing power consumption. On the other hand, even when the terminal device exists outside the vehicle, it may be desired to operate the transmission process and the reception process.
  • the terminal device according to the second modification of the present invention executes transmission processing and reception processing when approaching the base station device.
  • the communication system 100 according to the second modification is the same type as in FIG. 1, the base station apparatus 10 is the same type as in FIG. 2, and the terminal apparatus 14 is the same type as in FIG. 7 and FIG. It is. Below, it demonstrates focusing on a difference.
  • the estimation unit 86 is one of the transmission processing unit 82 and the reception processing unit 84. Is stopped, one of the transmission process and the reception process is stopped.
  • the extraction unit 66 receives the packet signal from the base station apparatus 10, that is, when the extraction unit 66 exists in the first area 210 and the second area 212 in FIG.
  • the transmission process and the reception process are executed by operating the unit 84.
  • connection unit 88 may switch the operation depending on whether or not it exists in the first area 210 instead of switching the operation depending on whether or not the packet signal from the base station apparatus 10 is received.
  • the estimation part 86 operates the transmission process part 82 and the reception process part 84.
  • the estimation part 86 stops one of the transmission process part 82 and the reception process part 84.
  • FIG. 12 is a flowchart showing a processing procedure in the terminal device 14 according to the second modification of the present invention. If the packet signal from the base station apparatus 10 is not received (N in S90), the estimation unit 86 executes the transmission process and stops the reception process (S92). On the other hand, if the packet signal from the base station apparatus 10 is received (Y in S90), the estimation unit 86 causes transmission processing and reception processing to be executed (S94).
  • FIG. 13 shows a configuration of a communication system 100 according to the third modification of the present invention. This corresponds to the case where one intersection is viewed from above, as in FIG. Compared with FIG. 1, FIG. 13 does not form the first area 210 but forms only the second area 212. In order to correspond to this, in the subframe configuration shown in FIG. 5A, only one of the priority period and the general period is included. Here, it is assumed that only the general period is included. Therefore, the vehicle transmission period in FIGS. 3B to 3D corresponds to the general period.
  • the base station apparatus 10 according to the third modification is the same type as that in FIG. 2, but does not execute processing related to the priority period. For this reason, the priority period is not included in the configuration of subframes and frames defined by the frame defining unit 40.
  • the setting unit 48 may be omitted.
  • the terminal device 14 according to the third modification is of the same type as that shown in FIGS. Similarly to the base station apparatus 10, the terminal apparatus 14 does not execute processing related to the priority period.
  • the extraction unit 66 identifies whether it exists in the second area 212 or outside the second area 214. This specification is made based on whether or not a packet signal from the base station apparatus 10 is received.
  • the extraction unit 66 when receiving a packet signal from the base station apparatus 10, the extraction unit 66 identifies the presence in the second area 212 and has not received the packet signal from the base station apparatus 10. In this case, the extraction unit 66 identifies the presence outside the second area 214. Further, the extraction unit 66 detects a movement from the second area outside 214 to the second area 212 and a movement from the second area outside 214 to the second area 212.
  • the extraction unit 66 When the extraction unit 66 detects a movement between the second area 212 and the second area 214, the extraction unit 66 performs a communication process between the communication process in the second area 212 and the communication process in the second area 214. change.
  • the communication processing in the second area 212 is use of a general period by the carrier sense unit 94. Since this is an operation constrained by the frame configuration, it can be said to be an operation according to the operation timing of the base station apparatus 10.
  • the communication processing outside the second area 214 is an operation that does not depend on the frame configuration by the carrier sense unit 94. This can be said to be an operation unrelated to the operation timing of the base station apparatus 10.
  • the terminal device according to the fourth modification is also carried by the user and moved. Since the terminal device operates with a built-in battery, low power consumption is desired. On the other hand, in order to ensure the safety of the user, it is required to inform the vehicle of the location of the user by transmitting a packet signal.
  • a terminal device carried by a user is referred to as a portable terminal device, and a terminal device installed at a predetermined position in the vehicle is referred to as an in-vehicle terminal device.
  • the portable terminal device transmits a packet signal with lower transmission power when present in the vehicle than when present in the vehicle.
  • the portable terminal device estimates whether it exists in the vehicle or outside the vehicle from the received strength (RSSI: Received Signal Strength Indication) of the packet signal broadcast from the in-vehicle terminal device.
  • RSSI Received Signal Strength Indication
  • the communication system 100 according to the fourth modification is the same type as that in FIG. 1, and the base station apparatus 10 is the same type as that in FIG. Below, it demonstrates focusing on a difference.
  • FIG. 14 shows a configuration of a portable terminal device 14a according to a fourth modification of the present invention.
  • the portable terminal device 14a includes an antenna 50, an RF unit 52, a modem unit 54, a processing unit 56, and a control unit 58.
  • the processing unit 56 includes a transmission processing unit 82, a reception processing unit 84, a transmission power adjustment unit 85, and an estimation unit 86. Since the antenna 50, the RF unit 52, and the modem unit 54 perform the same operations as those in FIG. 7, the description thereof is omitted here.
  • the transmission processing unit 82 corresponds to a part of the processing unit 56 in FIG. 7 that executes a process for informing a packet signal, and the reception processing unit 84 includes the packet signal in the processing unit 56 in FIG.
  • the generation unit 64, the notification unit 70, and the acquisition unit 72 of FIG. 7 are omitted in FIG. 14 to simplify the drawing, but are included in the processing unit 56.
  • the portable terminal device 14a is driven by a built-in battery.
  • the estimation unit 86 detects the RSSI of the packet signal notified from the in-vehicle terminal device, and estimates whether the portable terminal device 14a exists inside the vehicle 12 or outside the vehicle 12. Since the distance between the transmitting terminal and the receiving terminal can be estimated by RSSI, it can be estimated whether or not the vehicle 12 exists. Since the in-vehicle terminal device exists in the vehicle 12, if a general passenger car is assumed, if it can be estimated that the portable terminal device 14a exists within about 1.5 m from the in-vehicle terminal device, it may exist in the vehicle 12. Judgment is high.
  • the designer sets a setting value corresponding to the distance from the in-vehicle terminal device, which is estimated that the portable terminal device 14a exists in the vehicle 12, in the estimation unit 86.
  • the estimation unit 86 estimates whether the portable terminal device 14a exists inside the vehicle 12 or outside the vehicle 12 by comparing the set value with the RSSI of the packet signal notified from the in-vehicle terminal device. .
  • the estimation unit 86 compares the highest RSSI with the set value.
  • the transmission source of the packet signal is an in-vehicle terminal device can be specified by referring to the transmission source type stored in the header of the MAC frame.
  • the transmission source type is a base station device and a portable terminal device
  • the packet signal is not used for determining whether or not the portable terminal device 14a exists in the vehicle 12.
  • the estimation unit 86 sets in the transmission processing unit 82, the reception processing unit 84, and the transmission power adjustment unit 85 whether the portable terminal device 14a is estimated to be present in the vehicle 12 or is estimated to exist outside the vehicle 12. To do.
  • the transmission processing unit 82 receives position information from a GPS receiver or the like, and stores the position information in the data payload of the MAC frame.
  • the transmission processing unit 82 broadcasts and transmits a packet signal including the MAC frame at a predetermined timing.
  • the transmission power adjustment unit 85 adjusts transmission power when a packet signal is transmitted by the transmission processing unit 82, the modem unit 54, the RF unit 52, and the antenna 50. Specifically, the transmission power adjustment unit 85 sets the transmission power when it is estimated that the portable terminal device 14a exists in the vehicle 12 to be lower than the transmission power when it is estimated that the portable terminal device 14a exists outside the vehicle 12. .
  • the portable terminal device 14a When it is estimated that the portable terminal device 14a is present in the vehicle 12, it can be said that the user carrying the portable terminal device 14a is in a safe position, and therefore the necessity of notifying other vehicles of the presence is not necessary. Low. On the other hand, when it is estimated that the portable terminal device 14a exists outside the vehicle 12, it is highly necessary to notify the vehicle located in the vicinity of the presence of a pedestrian carrying the portable terminal device 14a.
  • the transmission power adjustment unit 85 adjusts the transmission power so that the packet signal is transmitted with a radio wave intensity reaching within a radius of 1 to 2 m, for example.
  • the portable terminal device 14a only needs to be able to communicate with the in-vehicle terminal device in the vehicle 12, so that the in-vehicle terminal device installed in the vehicle 12 receives the signal. It is good to adjust to the lowest possible transmission power.
  • the transmission power adjustment unit 85 adjusts the transmission power so that a packet signal is transmitted with a radio wave intensity reaching within a radius of 5 to 100 m, for example. From the viewpoint of traffic safety, it is desirable to transmit by radio waves that reach a long distance, but from the viewpoint of traffic of the battery of the portable terminal device 14a and the communication system 100 as a whole, radio waves that can reach only a short distance are used. It is desirable to send it out. The designer considers this trade-off relationship, and sets the transmission power when the portable terminal device 14a is estimated to exist outside the vehicle 12.
  • the reception processing unit 84 receives various types of information from the in-vehicle terminal device when it is estimated that the portable terminal device 14a exists in the vehicle 12.
  • the in-vehicle terminal device is generally installed in the vicinity of the driver's seat in the vehicle 12.
  • the in-vehicle terminal device and the portable terminal device 14a communicate with each other, so that the user sitting in the rear seat can use the service provided by the in-vehicle terminal device in the portable terminal device 14a.
  • the generation unit 53 of the in-vehicle terminal device generates a packet signal including a service menu provided to the portable terminal device 14a, and the transmission processing unit 82 notifies the packet signal.
  • the reception processing unit 84 of the portable terminal device 14a receives the packet signal.
  • FIG. 15 is a diagram illustrating an example of a service menu provided by the in-vehicle terminal device to the portable terminal device 14a.
  • road alignment information, traffic jam information, construction information, accident information, and weather information are provided.
  • FIG. 15 shows a service menu screen 70a displayed on the display of the portable terminal device 14a.
  • a user carrying the portable terminal device 14a selects a menu. For example, the corresponding area of the touch panel display is touched. Or use the operation keys to select the menu.
  • the generation unit 64 of the portable terminal device 14a generates a packet signal including the selection information, and the transmission processing unit 82 notifies the packet signal.
  • the reception processing unit 84 of the in-vehicle terminal device receives the packet signal.
  • the generating unit 64 of the in-vehicle terminal apparatus generates a packet signal including menu service information corresponding to the selection information.
  • the transmission processing unit 82 notifies the packet signal.
  • the generation unit 64 can use various service information such as road alignment information, traffic jam information, construction information, accident information, and weather information acquired from the base station device 10, other in-vehicle terminal devices, or navigation devices.
  • the reception processing unit 84 of the portable terminal device 14a receives the packet signal, and the notification unit 70 displays the service information included in the packet signal on the screen.
  • the above-described exchange of information between the in-vehicle terminal device and the portable terminal device 14a is executed by the above-described inter-vehicle communication.
  • the reception processing unit 84 stops the reception process by stopping the reception processing unit 84.
  • the stop of the reception process means that the data stored in the data payload of the packet signal is discarded without being processed.
  • the reception processing unit 84 may stop the reception process of the packet signal regardless of the transmission source type, or may stop the reception process of the packet signal notified from another terminal device 14. In the former, reception processing of all packet signals notified from the in-vehicle terminal device, the other portable terminal device 14a, and the base station device 10 is stopped. In the latter case, the reception processing of the packet signal notified from the in-vehicle terminal device and the other portable terminal device 14a is stopped, but the reception processing of the packet signal notified from the base station device 10 is not stopped.
  • the base station device 10 when the portable terminal device 14a is located within the radio wave range of the base station device 10, the base station device 10 provides the portable terminal device 14a by communicating with the base station device 10.
  • the service can be used by the portable terminal device 14a.
  • the generation unit 46 of the base station apparatus 10 generates a packet signal including a service menu provided to the portable terminal apparatus 14a, and a transmission processing unit (not shown) of the base station apparatus 10 notifies the packet signal.
  • the service menu includes traffic information, construction information, accident information, incident information, weather information, and the like.
  • the reception processing unit 84 of the portable terminal device 14a receives the packet signal notified from the base station device 10, and the notification unit 70 displays a service menu included in the packet signal on the screen. A user carrying the portable terminal device 14a selects a menu.
  • the generation unit 64 of the portable terminal device 14a generates a packet signal including the selection information, and the transmission processing unit 82 notifies the packet signal.
  • a reception processing unit (not shown) of the base station apparatus 10 receives the packet signal.
  • the generation unit 46 of the base station apparatus 10 generates a packet signal including service information of a menu corresponding to the selection information.
  • a transmission processing unit (not shown) of the base station apparatus 10 broadcasts the packet signal.
  • the generation unit 46 can use various service information such as traffic information, construction information, accident information, incident information, and weather information acquired from various servers on the network 202, other base station devices 10, and terminal devices 14.
  • the reception processing unit 84 of the portable terminal device 14a receives the packet signal, and the notification unit 70 displays the service information included in the packet signal on the screen.
  • the above-described information exchange between the base station device 10 and the portable terminal device 14a is executed by the road-to-vehicle communication described above.
  • FIG. 16 is a flowchart showing a processing procedure of the portable terminal device 14a according to the fourth modification.
  • the estimation unit 86 detects the reception intensity of the packet signal (S90).
  • the estimation unit 86 compares the received intensity with the set value (S92).
  • the estimation unit 86 estimates that the portable terminal device 14a exists outside the vehicle 12, and the transmission power adjustment unit 85 sets the transmission power to normal transmission power.
  • the unit 82 transmits the packet signal with normal transmission power (S94).
  • the reception processing unit 84 stops receiving packet signals broadcast from other terminal devices (S96).
  • the estimation unit 86 estimates that the portable terminal device 14a is present in the vehicle 12, and the transmission power adjustment unit 85 sets the transmission power to lower than normal. Then, the transmission processing unit 82 transmits the packet signal with low transmission power (S98).
  • the terminal device according to the fifth modification is also carried by the user and moved.
  • the built-in battery of the portable terminal device 14a is further saved.
  • the portable terminal device transmits a packet signal including the position information at a lower frequency than when the portable terminal device is present outside the vehicle.
  • the communication system 100 according to the fifth modification is the same type as that in FIG. 1, and the base station apparatus 10 is the same type as that in FIG.
  • the in-vehicle terminal device is the same type as in FIG. 7, and the portable terminal device 14a is the same type as in FIG. Below, it demonstrates focusing on a difference.
  • the transmission processing unit 82 of the portable terminal device 14a performs position information less frequently than when it is estimated that the portable terminal device 14a exists outside the vehicle 12.
  • the packet signal including the position information is notified because the in-vehicle terminal device checks whether the portable terminal device 14a exists in the vehicle 12. Is the main purpose.
  • the in-vehicle terminal device notifies the packet signal including the service menu described above when the portable terminal device 14a is present in the vehicle 12, and does not notify the packet signal when it does not exist.
  • the estimation unit 86 estimates that the portable terminal device 14a exists outside the vehicle 12
  • the transmission processing unit 82 transmits a packet signal including position information once every 100 msec and estimates that the portable terminal device 14a exists inside the vehicle 12. If transmitted, it is transmitted once every 1 min.
  • FIG. 17 is a flowchart showing a processing procedure of the portable terminal device 14a according to the fifth modification.
  • the flowchart of FIG. 17 has a configuration in which steps S95 and S98 are added to the flowchart of FIG.
  • the estimation unit 86 detects the reception intensity of the packet signal (S90).
  • the estimation unit 86 compares the received intensity with the set value (S92). When the reception intensity is less than the set value (Y in S92), the estimation unit 86 estimates that the portable terminal device 14a exists outside the vehicle 12, and the transmission power adjustment unit 85 sets the transmission power to normal transmission power.
  • the unit 82 transmits the packet signal with normal transmission power (S94).
  • the transmission processing unit 82 transmits a packet signal including position information at a normal transmission frequency (S95).
  • the reception processing unit 84 stops receiving packet signals broadcast from other terminal devices (S96).
  • the estimation unit 86 estimates that the portable terminal device 14a is present in the vehicle 12, and the transmission power adjustment unit 85 sets the transmission power to lower than normal. Then, the transmission processing unit 82 transmits the packet signal with low transmission power (S98). The transmission processing unit 82 transmits a packet signal including position information at a lower frequency than usual (S99).
  • the terminal device according to the sixth modification is also carried by the user and moved.
  • the portable terminal device transmits the packet signal with lower transmission power than when the portable terminal device exists outside the building.
  • the portable terminal device estimates whether it exists in the building or outside the building from the reception intensity of the packet signal broadcast from the indoor wireless device.
  • An indoor wireless device is installed in a building and provides various information toward a terminal device existing in the building. For example, indoor wireless devices are installed in buildings installed in highway service areas, gas stations, and the like. Moreover, you may install in other buildings where many people enter and exit, such as a convenience store, a restaurant, and a shopping store.
  • the indoor wireless device may be basically the same type as the terminal device of FIG.
  • the indoor radio apparatus can be configured not to receive the packet signal from the base station apparatus 10 and not to transfer the packet signal. In this case, the configuration related to the function can be omitted, and wireless communication using only CSMA / CA is executed. Further, since the indoor wireless device is fixedly installed, a configuration unique to the mobile terminal such as a GPS receiver can be omitted.
  • the communication system 100 according to the sixth modification has a configuration in which an indoor wireless device is added to the communication system 100 in FIG. 1, and the base station device 10 is the same type as that in FIG.
  • the in-vehicle terminal device is the same type as in FIG. 7, and the portable terminal device 14a is the same type as in FIG. Below, it demonstrates focusing on a difference.
  • the estimation unit 86 detects the reception intensity of the packet signal broadcast from the indoor wireless device, and estimates whether the portable terminal device 14a exists indoors or outdoors. As described above, since the indoor wireless device transmits a packet signal with transmission power having a reception range in the building, the estimation unit 86 determines whether or not the packet signal notified from the indoor wireless device is detected. It can be estimated whether the device 14a exists indoors or outdoors. If the packet signal can be detected, it can be estimated that the packet signal is present indoors.
  • the transmission source of the packet signal is an indoor wireless device can be specified by referring to the transmission source type stored in the header of the MAC frame.
  • the transmission source type is a base station device, an in-vehicle terminal device, and a portable terminal device
  • the packet signal is not used for determining whether the portable terminal device 14a exists indoors.
  • the estimation unit 86 sets in the transmission processing unit 82, the reception processing unit 84, and the transmission power adjustment unit 85 whether the portable terminal device 14a is estimated to be present indoors or is estimated to be present outdoors.
  • the transmission processing unit 82 receives position information from a GPS receiver or the like, and stores the position information in the data payload of the MAC frame.
  • the transmission processing unit 82 broadcasts and transmits a packet signal including the MAC frame at a predetermined timing.
  • the transmission power adjustment unit 85 adjusts transmission power when a packet signal is transmitted by the transmission processing unit 82, the modem unit 54, the RF unit 52, and the antenna 50. Specifically, the transmission power adjustment unit 85 sets the transmission power when the portable terminal device 14a is estimated to be present indoors lower than the transmission power when it is estimated that the portable terminal device 14a is present outdoors.
  • the portable terminal device 14a When it is estimated that the portable terminal device 14a exists indoors, it can be said that the user carrying the portable terminal device 14a is in a safe position, and thus the necessity of notifying the vehicle of the presence is low. On the other hand, when it is estimated that the portable terminal device 14a exists outdoors, it is highly necessary to notify the vehicle located in the vicinity of the presence of a pedestrian carrying the portable terminal device 14a.
  • the portable terminal device 14a can use the service provided by the indoor wireless device by the communication between the portable terminal device 14a and the indoor wireless device.
  • the generation unit 64 of the indoor wireless device generates a packet signal including a service menu provided to the portable terminal device 14a, and a transmission processing unit (not shown) of the indoor wireless device 0 notifies the packet signal.
  • the service menu includes map information, position information, product information, coupons, questionnaires, and the like.
  • the reception processing unit 84 of the portable terminal device 14a receives the packet signal notified from the indoor wireless device, and the notification unit 70 displays the service menu included in the packet signal on the screen. A user carrying the portable terminal device 14a selects a menu.
  • the generation unit 64 of the portable terminal device 14a generates a packet signal including the selection information, and the transmission processing unit 82 notifies the packet signal.
  • a reception processing unit (not shown) of the indoor wireless device receives the packet signal.
  • the generation unit 64 of the base station apparatus 10 generates a packet signal including service information of a menu corresponding to the selection information.
  • a transmission processing unit (not shown) of the indoor radio apparatus notifies the packet signal.
  • the reception processing unit 84 of the portable terminal device 14a receives the packet signal, and the notification unit 70 displays the service information included in the packet signal on the screen.
  • the exchange of information between the indoor wireless device and the portable terminal device 14a is executed by the above-described inter-vehicle communication.
  • the estimation unit 86 stops the reception process by stopping the reception processing unit 84 when it is estimated that the portable terminal device 14a exists outdoors.
  • the stop of the reception process means that the data stored in the data payload of the packet signal is discarded without being processed.
  • the reception processing unit 84 may stop the reception process of the packet signal regardless of the transmission source type, or may stop the reception process of the packet signal notified from another terminal device 14.
  • the transmission processing unit 82 of the portable terminal device 14a includes a packet signal that includes position information at a lower frequency than when estimated to be present outdoors. May be notified.
  • the necessity of notifying the vehicle of the presence is low.
  • the terminal device according to the seventh modification is also carried by the user and moved.
  • a mode in which the terminal device is installed and used at a predetermined position in the vehicle is referred to as an in-vehicle device mode
  • a mode in which the terminal device is carried by the user is referred to as a pedestrian terminal mode.
  • the said terminal device is equipped with the function of both onboard equipment and a pedestrian terminal device.
  • in-vehicle equipment is a concept that includes the terminal device operating in the on-vehicle equipment mode in addition to the dedicated equipment.
  • the pedestrian terminal device has a concept including the terminal device operating in the pedestrian terminal mode in addition to the dedicated machine.
  • the terminal device may be a dedicated machine having the functions of both the vehicle-mounted device and the pedestrian terminal device, or may be a smartphone, tablet, or car navigation device having both functions. Since the terminal device operates with a built-in battery, low power consumption is desired. On the other hand, in order to ensure the safety of the user, it is required to inform the vehicle of the location of the user by transmitting a packet signal. Furthermore, when the user installs the terminal device at a predetermined position in the vehicle, it is desired to operate in the same manner as the vehicle-mounted device.
  • the terminal device according to the seventh modification executes different reception processes depending on whether the terminal device exists in the vehicle or outside the vehicle.
  • the communication system 100 according to the seventh modification 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 FIGS. It is. Below, it demonstrates focusing on a difference.
  • the terminal device 14 is installed in a folder or a docking station (hereinafter collectively referred to as a folder) when used in the vehicle 12.
  • This folder is provided with a power supply terminal (not shown), and the connection portion 88 can receive power supply from this power supply terminal.
  • the estimation unit 86 detects that the connection unit 88 is connected to the power supply terminal, the estimation unit 86 estimates that the terminal device 14 is present in the vehicle 12, and detects that the terminal device 14 is not connected to the power supply terminal. Presumed to exist outside.
  • the estimation unit 86 determines that the terminal device 14 is in the vehicle 12 depending on whether or not the casing of the terminal device 14 and the above-described folder are in physical contact, not whether or not the connection unit 88 is connected to the power supply terminal. Or existing outside the vehicle 12 may be estimated.
  • the estimation unit 86 sets the terminal device 14 to the vehicle-mounted device mode when it is estimated that the terminal device 14 exists in the vehicle 12, and sets the pedestrian terminal mode when it is estimated that the terminal device 14 exists outside the vehicle 12.
  • the estimation unit 86 causes the reception processing unit 84 to execute different reception processes in the vehicle-mounted device mode and the pedestrian terminal mode.
  • the reception processing unit 84 performs simpler reception processing than when the terminal device 14 exists inside the vehicle 12. Specifically, when it is estimated that the terminal device 14 exists in the vehicle 12, the data stored in the packet signals from the base station device 10, the vehicle-mounted device, and the pedestrian terminal device are processed.
  • the terminal device 14 when the terminal device 14 exists outside the vehicle 12, the data stored in the packet signal from the base station device 10 and the vehicle-mounted device is processed, but the data stored in the packet signal from the pedestrian terminal device is discarded. To do. That is, the data stored in the packet signal from the other terminal device outside the vehicle 12 is discarded.
  • the terminal device 14 When the terminal device 14 is carried by a pedestrian and is operating in the pedestrian terminal mode, the main target for avoiding the danger is a vehicle. Pedestrians are not the main target because it is difficult for pedestrians to have a big accident. Therefore, the terminal device 14 only needs to be able to acquire the position of the vehicle located in the vicinity of the pedestrian, and the request for acquiring the positions of other pedestrians located in the vicinity of the pedestrian is low.
  • FIG. 18 is a flowchart showing a processing procedure in the reception processing unit 84 according to the seventh modification.
  • the reception processing unit 84 determines whether the mode is the vehicle-mounted device mode or the pedestrian terminal mode (S102). When it is pedestrian terminal mode (pedestrian of S102), the reception processing unit 84 determines whether or not the transmission source type of the received packet signal is a pedestrian terminal device (S104).
  • the transmission source type can be specified with reference to the header of the MAC frame input from the modem unit 54.
  • the reception processing unit 84 discards the data payload of the packet signal without processing it (S108).
  • the transmission source type is the vehicle-mounted device or the base station device 10 (N in S104)
  • application data is extracted from the data payload of the packet signal, and the application data is processed (S106).
  • the reception processing unit 84 extracts application data from the data payload of the received packet signal regardless of the transmission source type, and processes the application data ( S106).
  • the terminal device also includes an in-vehicle device mode and a pedestrian terminal mode.
  • the assumed road safety risk model differs between a vehicle equipped with an onboard device and a pedestrian carrying a pedestrian terminal device. In the case of a vehicle, a case where the vehicle is primarily harmed by another vehicle, a case where the vehicle is harmed, or a case where the vehicle is harmed by a pedestrian is assumed. In the case of pedestrians, there are cases where the vehicle is primarily harmed.
  • the communication system 100 according to the eighth modification 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 FIGS. It is. Below, it demonstrates focusing on a difference.
  • the estimation unit 86 causes the reception processing unit 84 to execute different risk determination processes in the vehicle-mounted device mode and the pedestrian terminal mode.
  • the reception processing unit 84 acquires position information from the data payload of the packet signal received from the base station device 10, the vehicle-mounted device, or the pedestrian terminal device.
  • the reception processing unit 84 determines whether to notify the presence of a vehicle or a pedestrian specified by the position information by executing a risk determination process.
  • the danger area setting range differs between the danger determination process in the onboard mode (hereinafter referred to as the first danger determination process) and the danger determination process in the pedestrian terminal mode (hereinafter referred to as the second danger determination process).
  • the danger level of the area in the traveling direction is high, and the danger level is relatively low in the left and right and rear areas of the vehicle.
  • the danger area (hereinafter referred to as the first danger area) in the first danger determination process is set to a shape in which the traveling direction of the vehicle is relatively swollen relative to other directions.
  • the danger area (hereinafter referred to as the second danger area) in the second danger determination process is set in a circle around the pedestrian.
  • the reception processing unit 84 When the reception processing unit 84 receives position information from the vehicle-mounted device or the pedestrian terminal device located in the first danger area in the vehicle-mounted device mode, the reception processing unit 84 basically notifies the driver of the presence of the position information. When position information is received from an onboard device or a pedestrian terminal device located outside, the presence is not notified.
  • the reception processing unit 84 When receiving position information from the vehicle-mounted device located in the second danger area in the pedestrian terminal mode, the reception processing unit 84 basically notifies the pedestrian of the presence and is located outside the second danger area. When location information is received from the OBE, the presence is not notified. In addition, the reception via the base station apparatus 10 is also included in the reception of the positional information from the vehicle-mounted device or the pedestrian terminal device.
  • the reception processing unit 84 Even if the reception processing unit 84 receives position information from the vehicle-mounted device or the pedestrian terminal device located in the first danger area in the vehicle-mounted device mode, the reception processing unit 84 does not notify the presence unconditionally, Whether or not to notify may be determined depending on whether or not the above is satisfied.
  • the traveling direction and moving speed included in the position information can be used for the condition.
  • the traveling direction included in the position information is referred to and it is determined whether the vehicle on which the vehicle-mounted device is mounted approaches or leaves the vehicle. In addition, what is necessary is just to observe the time change of the distance between vehicles when the advancing direction cannot be acquired. When you leave your own vehicle, you are not notified of the presence of that vehicle. Also, even when the vehicle on which the vehicle-mounted device is mounted approaches the own vehicle, if the traveling direction of the approaching vehicle and the traveling direction of the own vehicle are substantially opposite, The coming vehicle is determined as an oncoming vehicle, and the presence of the vehicle is not notified. Further, when position information is received from the vehicle-mounted device, the moving speed included in the position information is referred to, and if the speed of the vehicle on which the vehicle-mounted device is mounted is slower than the set value, the presence of the vehicle is not notified.
  • the reception processing unit 84 Even if the reception processing unit 84 receives the position information from the vehicle-mounted device located in the second danger area in the pedestrian terminal mode, the reception processing unit 84 does not notify the existence unconditionally but satisfies the predetermined condition. The presence or absence of notification may be determined depending on the above. Similar to the vehicle-mounted device mode, the traveling direction included in the position information can be used for the condition.
  • the traveling direction included in the position information is referenced to determine whether the vehicle on which the vehicle-mounted device is mounted approaches or leaves the pedestrian. When leaving, the presence of the vehicle going away is not notified.
  • FIG. 19 is a diagram for explaining the first risk determination process and the second risk determination process.
  • the first vehicle 12a, the second vehicle 12b, the third vehicle 12c, the fourth vehicle 12d, the fifth vehicle 12e, the sixth vehicle 12f, the seventh vehicle 12g, and the eighth vehicle 12h are each equipped with a terminal device (not shown).
  • Each of the first pedestrian 16a and the second pedestrian 16b carries a terminal device (not shown).
  • the first vehicle 12a, the second vehicle 12b, the third vehicle 12c, and the fourth vehicle 12d are traveling from “South” toward “North”.
  • the fifth vehicle 12e, the sixth vehicle 12f, and the seventh vehicle 12g are traveling from “north” to “south”.
  • the eighth vehicle 12h is traveling from “west” to “east” and is traveling toward the T-junction.
  • the first pedestrian 16a and the second pedestrian 16b are located on the shoulders of the priority road, and in particular, the first pedestrian 16a is located near the T-shaped road.
  • the reception processing unit 84 of the terminal device mounted on the first vehicle 12a sets the first danger area 220.
  • the first danger area 220 there are a second vehicle 12b, a fourth vehicle 12d, a fifth vehicle 12e, a sixth vehicle 12f, a seventh vehicle 12g, an eighth vehicle 12h, and a first pedestrian 16a.
  • the reception processing unit 84 of the terminal device mounted on the first vehicle 12a includes the second vehicle 12b, the fourth vehicle 12d, the fifth vehicle 12e, the sixth vehicle 12f, the seventh vehicle 12g, the eighth vehicle 12h, and the first walking.
  • the reception processing unit 84 of the terminal device mounted on the first vehicle 12a acquires position information from the terminal device mounted on the fourth vehicle 12d or the second vehicle 12b, The existence of the fourth vehicle 12d or the second vehicle 12b may be notified only when the distance between the four vehicles 12d or the distance between the first vehicle 12a and the second vehicle 12b is narrowed.
  • the fifth vehicle 12e, the sixth vehicle 12f, and the seventh vehicle 12g are oncoming vehicles of the first vehicle 12a. Unless there is a large change in the traveling direction of the fifth vehicle 12e, the sixth vehicle 12f, and the seventh vehicle 12g, it can be said that the possibility of a collision with the first vehicle 12a is low. Therefore, when the reception processing unit 84 of the terminal device mounted on the first vehicle 12a acquires position information from the terminal devices mounted on the fifth vehicle 12e, the sixth vehicle 12f, and the seventh vehicle 12g, the presence of the presence information. Notification may be omitted.
  • the reception processing unit 84 of the terminal device mounted on the first vehicle 12a acquires position information from the terminal device mounted on the eighth vehicle 12h, Notify existence.
  • the presence notification may be omitted.
  • the reception processing unit 84 of the terminal device carried by the first pedestrian 16a sets the second danger area 222.
  • the second danger area 222 there are a fourth vehicle 12d, a sixth vehicle 12f, a seventh vehicle 12g, and an eighth vehicle 12h.
  • the reception processing unit 84 of the terminal device carried by the first pedestrian 16a obtains position information from any of the terminal devices mounted on the fourth vehicle 12d, the sixth vehicle 12f, the seventh vehicle 12g, and the eighth vehicle 12h.
  • the presence is displayed on the display, voice guidance is output, or the casing is vibrated. Two or more of them may be executed.
  • the designer sets the area of the second danger area 222 in consideration of the trade-off. There is a view that the area of the second danger area 222 may be smaller than the area of the first danger area 220 because the vehicle side is primarily obligated to avoid a collision between the pedestrian and the vehicle.
  • FIG. 20 is a flowchart showing a processing procedure in the reception processing unit 84 according to the eighth modification.
  • Receiving processing part 84 will acquire position information transmitted from other terminal units (S110), and will judge whether it is onboard equipment mode or pedestrian terminal mode (S112).
  • S110 On-vehicle equipment mode
  • S112 pedestrian terminal mode
  • S114 On-vehicle equipment mode
  • S116 a 2nd danger determination process
  • the reception processing unit 84 determines whether or not to notify the driver or pedestrian of the presence of the vehicle or pedestrian specified by the received position information as a result of the first risk determination process or the second risk determination process ( S118). If it is determined that notification is necessary (Y in S118), the reception processing unit 84 notifies the presence of the vehicle or pedestrian (S120). If it is determined that the notification is unnecessary (N in S118), the process in step S120 is skipped.
  • the terminal device according to the ninth modification also includes an in-vehicle device mode and a pedestrian terminal mode.
  • the communication system 100 according to the ninth modification is the same type as in FIG. 1, the base station apparatus 10 is the same type as in FIG. 2, and the terminal apparatus 14 is the same type as in FIG. 7 and FIG. It is. Below, it demonstrates focusing on a difference.
  • the estimation unit 86 causes the transmission processing unit 82 to execute different transmission processes in the vehicle-mounted device mode and the pedestrian terminal mode.
  • the transmission processing unit 82 executes transmission processing with different transmission frequencies in the vehicle-mounted device mode and the pedestrian terminal mode.
  • the transmission process in the pedestrian terminal mode is executed at a lower frequency than the transmission process in the vehicle-mounted device mode.
  • the transmission processing unit 82 receives position information from a GPS receiver or the like, and stores the position information in the data payload of the MAC frame.
  • the transmission processing unit 82 broadcasts and transmits a packet signal including the MAC frame at a predetermined timing.
  • the transmission frequency is different between the vehicle-mounted device mode and the pedestrian terminal mode.
  • FIG. 21 is a flowchart showing a processing procedure in the transmission processing unit 82 according to the ninth modification.
  • the transmission process part 82 determines whether it is onboard equipment mode or pedestrian terminal mode (S130). When it is pedestrian terminal mode (pedestrian of S130), transmission processing part 82 changes the transmission frequency of position information to low (S132). If it is in the vehicle-mounted device mode (vehicle mounted in S130), the process in step S132 is skipped. For example, it may be transmitted once every 100 msec when the transmission frequency of the position information is normal, or once every 500 msec or once every 1 min when the frequency is low.
  • the transmission processing unit 82 transmits the position information with the set transmission frequency (S134).
  • the terminal device according to the tenth modification is also carried by the user and moved. Since the terminal device operates with a built-in battery, low power consumption is desired. On the other hand, ensuring the safety of the user is also required.
  • the terminal device executes transmission processing and reception processing when carried by the user, and at least one of transmission processing and reception processing when not carried by the user To stop.
  • the communication system 100 according to the tenth modification 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 FIGS. It is. Below, it demonstrates focusing on a difference.
  • the acquisition unit 72 acquires position information from a GPS receiver (not shown).
  • the estimation unit 86 estimates whether or not the terminal device 14 is in a carried state from the change in position information acquired by the acquisition unit 72. When there is a change in position, the estimation unit 86 estimates that the vehicle is in a carried state. When there is no change in position, the estimation unit 86 estimates that the vehicle is not in the carried state but is in a state where it is placed somewhere.
  • the acquisition unit 72 may acquire vibration information from an acceleration sensor (not shown).
  • the estimation unit 86 estimates whether or not the terminal device 14 is in the carried state from the vibration information acquired by the acquisition unit 72. When the vibration component is detected, the estimation unit 86 estimates that the device is in the carried state, and when the vibration component is not detected, the estimation unit 86 estimates that the device is not in the carried state but is placed somewhere.
  • the terminal device 14 is a dedicated machine for the pedestrian terminal device and the terminal device 14 is estimated to be present in the vehicle 12 by the same processing as the first to third and seventh to ninth modifications, The estimation unit 86 may determine that it is not in the carried state.
  • the estimation unit 86 When estimating that the terminal device 14 is in the carried state, the estimation unit 86 operates the transmission processing unit 82 and the reception processing unit 84 to execute transmission processing and reception processing. On the other hand, when the estimation unit 86 estimates that it is not in the carried state, the estimation unit 86 stops one of the transmission processing and the reception processing by stopping one of the transmission processing unit 82 and the reception processing unit 84. For example, the estimation unit 86 operates only the transmission processing unit 82 and stops the reception processing unit 84. Note that the reverse may be possible.
  • the estimation unit 86 may cause the reception processing unit 84 to execute different reception processes depending on whether or not the terminal device 14 is in the carried state.
  • the estimation unit 86 may cause the reception processing unit 84 to execute different risk determination processes depending on whether or not the terminal device 14 is in the carried state.
  • the estimation unit 86 may cause the transmission processing unit 82 to execute different transmission processing depending on whether or not the terminal device 14 is in the carried state. In any case, the case of being in the vehicle may be read when the case is in the carried state and the case of being outside the vehicle is not read in the case of the carried state.
  • the change of the area is notified, it is possible to notify the driver of the importance set for the traveling area.
  • the driver since the driver is informed of the importance set for the traveling area, the driver can be alerted.
  • the probability of occurrence of a collision accident can be suppressed.
  • priority since priority is given to the area according to the importance of the packet signal to be notified, important information can be transmitted with priority.
  • the priority with respect to the area is defined according to the quality of the received signal, transmission processing according to the quality can be realized.
  • the priority with respect to the area is defined according to the distance from the base station apparatus, transmission processing according to the distance can be realized.
  • the notification mode since the notification mode is changed according to the area, the area can be recognized accurately.
  • terminal devices existing in the first area around the base station apparatus can broadcast packet signals.
  • terminal apparatuses existing in the second area surrounding the first area broadcast packet signals. Since it is possible, the priority of communication in the second area can be improved. Moreover, since the priority of communication in the second area is improved, it is possible to improve the reception probability of the packet signal broadcast from the terminal device existing in the second area. Further, since the reception probability of the packet signal broadcast from the terminal device existing in the second area is improved, important data can be transmitted with priority. Also, since the first arrangement and the second arrangement can be switched, it is possible to switch between improving the communication priority in the first area and improving the communication priority in the second area.
  • the area to be prioritized can be selected according to the intersection.
  • the processing can be simplified.
  • a range in which the propagation loss is within a predetermined level can be defined as the first area.
  • the range in which the propagation loss is within a predetermined level is defined in the first area, the vicinity of the center of the intersection can be used as the first area.
  • the time division multiplexing by slots is executed in the priority period, the error rate can be reduced.
  • CSMA / CA is performed in a general period, the number of terminal devices can be adjusted flexibly.
  • the subframe used by the other base station apparatus is specified based on the packet signal received from the terminal apparatus as well as the packet signal directly received from the other base station apparatus.
  • the frame identification accuracy can be improved.
  • the accuracy of identifying subframes in use is improved, the probability of collision between packet signals transmitted from the base station apparatus can be reduced.
  • the terminal apparatus can accurately recognize the control information. Further, since the control information is accurately recognized, the road and vehicle transmission period can be accurately recognized. Further, since the road and vehicle transmission period is accurately recognized, the collision probability of the packet signal can be reduced.
  • a subframe other than the currently used subframe is used preferentially, it is possible to reduce the possibility of transmitting a packet signal at a timing overlapping with packet signals from other base station apparatuses. Further, when any subframe is used by another base station apparatus, a subframe with low received power is selected, so that the influence of packet signal interference can be suppressed. Further, since the received power of the terminal device is used as the received power from another base station device that is the transmission source of the control information relayed by the terminal device, the received power estimation process can be simplified.
  • the transmission process and the reception process are executed when the vehicle is present in the vehicle, the same process as that of the in-vehicle terminal device can be executed. Moreover, when it exists out of a vehicle, since one of a transmission process and a reception process is stopped, power consumption can be reduced. Moreover, since it only performs a transmission process when it exists outside a vehicle, it can notify an existing position, reducing power consumption.
  • the function of the terminal device can be installed in a mobile phone terminal or the like. Further, since the function of the terminal device is mounted on a mobile phone terminal or the like, the communication system can be easily spread. Moreover, even if it is battery-powered, if it enters into a predetermined area, since a transmission process and a reception process will be performed, the process similar to the vehicle-mounted terminal device can be performed as needed. Moreover, when it exists outside an area, since one of a transmission process and a reception process is stopped, power consumption can be reduced.
  • the battery can be saved by transmitting the packet signal with lower power than when the portable terminal device is present outside the vehicle. Further, when the portable terminal device is present in the vehicle, the battery can be saved by notifying the position information less frequently than when the portable terminal device is present outside the vehicle. In addition, when a portable terminal device exists in a vehicle, since a user will also exist in a vehicle, the necessity to notify the presence to another vehicle becomes low. Further, when the portable terminal device exists outside the vehicle, the battery can be saved by stopping the reception process.
  • the convenience of passengers can be improved by using at least part of the services provided by the in-vehicle terminal device in the vehicle.
  • the convenience of the pedestrian who carries the portable terminal device can be improved by using the service provided by each in the radio wave range of the building and the roadside unit.
  • processing suitable for the mode can be performed by changing the content of reception processing or the content of transmission processing depending on the mode.
  • power consumption can be reduced by simplifying reception processing and transmission processing.
  • the process suitable for each danger model of a vehicle and a pedestrian is attained by changing a danger determination process with onboard equipment mode and pedestrian terminal mode.
  • the transmission process and the reception process are executed, so that the safety of the user can be improved.
  • the terminal device is not carried by the user, at least one of the transmission process and the reception process is stopped, so that power consumption can be reduced.
  • the terminal device is not carried by the user, the user is in a safe place or away from the terminal device. In the former case, it is not necessary to improve the safety, and in the latter case, the effectiveness of the process for improving the safety is not ensured. Therefore, priority is given to reducing power consumption.
  • the transmission processing unit 82 and the reception processing unit 84 One of them is stopped.
  • the present invention is not limited thereto, and for example, the estimation unit 86 may stop both the transmission processing unit 82 and the reception processing unit 84 in the above case. According to the first and second modifications, power consumption can be reduced.
  • a wireless device is a wireless device that performs communication with another wireless device, and includes a communication unit that performs transmission processing and reception processing, and the wireless device is present in the vehicle.
  • An estimator that estimates whether it exists outside.
  • the estimation unit estimates that the wireless device is present in the vehicle, the communication unit transmits a signal with lower transmission power than when the wireless device exists outside the vehicle.
  • the power consumption of the wireless device can be reduced by transmitting a signal with lower transmission power than when the wireless device is present outside the vehicle.
  • the communication unit may transmit a signal at a lower frequency when the estimation unit estimates that the wireless device is present in the vehicle than when the communication unit exists outside the vehicle. According to this, the power consumption of the wireless device can be further reduced.
  • the communication unit may execute the transmission process and the reception process when the estimation unit estimates that the wireless device is present in the vehicle, and may stop the reception process when it is estimated that the wireless device exists outside the vehicle. Since the transmission process and the reception process are executed when the vehicle is present in the vehicle, the same process as that of the in-vehicle terminal device can be executed. Further, when the vehicle is present outside the vehicle, the transmission process is executed and the reception process is stopped, so that the presence position can be notified while reducing power consumption.
  • This device is a wireless device that performs communication with other wireless devices, and the first area and the second area are defined as areas having different priorities from the first area to the second area.
  • a detection unit that detects movement; a communication unit that changes communication processing defined in the first area to communication processing defined in the second area when the detection unit detects movement; and Or an estimation unit that estimates whether the vehicle exists outside the vehicle.
  • the communication unit executes different reception processes depending on whether the wireless device estimated by the estimation unit is present inside the vehicle or outside the vehicle.
  • the communication unit may discard the data received from another wireless device existing outside the vehicle when the estimating unit estimates that the wireless device exists outside the vehicle. According to this, the load on the wireless device can be reduced.
  • Still another aspect of the present invention is also a wireless device.
  • This device is a wireless device that performs communication with other wireless devices, and the first area and the second area are defined as areas having different priorities from the first area to the second area.
  • a detection unit that detects movement; a communication unit that changes communication processing defined in the first area to communication processing defined in the second area when the detection unit detects movement; and Or an estimation unit that estimates whether the vehicle exists outside the vehicle.
  • the communication unit executes the transmission process at different transmission frequencies depending on whether the wireless device estimated by the estimation unit is present inside the vehicle or outside the vehicle.
  • the communication unit may execute the transmission process at a lower frequency than when the communication unit exists inside the vehicle. According to this, the power consumption of the wireless device can be reduced.
  • Still another aspect of the present invention is also a wireless device.
  • This device is a wireless device that performs communication with other wireless devices, and the first area and the second area are defined as areas having different priorities from the first area to the second area.
  • a detection unit that detects movement; a communication unit that changes communication processing defined in the first area to communication processing defined in the second area when the detection unit detects movement; and Or an estimation unit that estimates whether the vehicle exists outside the vehicle.
  • the communication unit performs transmission processing and reception processing when the estimation unit estimates that the wireless device is present in the vehicle, and performs transmission processing and reception processing when the estimation unit estimates that the wireless device is present outside the vehicle. Stop at least one of the
  • the transmission process and the reception process are executed when the vehicle is present in the vehicle, the same process as that of the in-vehicle terminal device can be executed. Moreover, when it exists outside a vehicle, since at least one of a transmission process and a reception process is stopped, power consumption can be reduced.
  • a notification unit that notifies the change of the area may be further provided. According to this, since the change of the area is notified, the importance set for the traveling area can be notified to the user.
  • Still another aspect of the present invention is also a wireless device.
  • This device is a wireless device that performs communication with other wireless devices, and when the wireless communication device estimates that the wireless device is in a carried state and the estimating portion is in a carried state, transmission processing is performed. And a communication unit that executes reception processing. The communication unit stops at least one of the transmission process and the reception process when it is estimated that the estimation unit is not in the carried state.
  • the transmission process and the reception process are executed, so that a sufficient function can be exhibited. Further, when not in the carried state, the power consumption can be reduced because at least one of the transmission process and the reception process is stopped.
  • the present invention can be used for a portable terminal device.

Abstract

L'invention concerne une unité de traitement de transmission (82) qui exécute un traitement de transmission, et une unité de traitement de réception (84) qui exécute un traitement de réception. Une unité d'estimation (86) estime si un appareil terminal portable (14a) se trouve à l'intérieur d'un véhicule ou à l'extérieur du véhicule. Dans le cas où l'unité d'estimation (86) estime que l'appareil terminal portable (14a) se trouve à l'intérieur du véhicule, l'unité de traitement de transmission (82) transmet les signaux avec une puissance de transmission inférieure à la puissance de transmission avec laquelle sont transmis les signaux dans le cas où l'appareil terminal portable se trouve à l'extérieur du véhicule.
PCT/JP2012/008090 2011-12-21 2012-12-19 Appareil sans fil WO2013094187A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2011-279506 2011-12-21
JP2011-279459 2011-12-21
JP2011279459A JP2015043477A (ja) 2011-12-21 2011-12-21 無線装置
JP2011279506A JP2015043478A (ja) 2011-12-21 2011-12-21 無線装置

Publications (1)

Publication Number Publication Date
WO2013094187A1 true WO2013094187A1 (fr) 2013-06-27

Family

ID=48668105

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2012/008090 WO2013094187A1 (fr) 2011-12-21 2012-12-19 Appareil sans fil

Country Status (1)

Country Link
WO (1) WO2013094187A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7300870B2 (ja) 2018-04-06 2023-06-30 ロベルト・ボッシュ・ゲゼルシャフト・ミト・ベシュレンクテル・ハフツング 車両のためのデータレコーダ装置

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003309630A (ja) * 2002-04-12 2003-10-31 Yuhshin Co Ltd 携帯送受信装置
JP2005012491A (ja) * 2003-06-19 2005-01-13 Hitachi Ltd 移動通信装置
JP2005009933A (ja) * 2003-06-17 2005-01-13 Mazda Motor Corp 走行支援システム、車載端末器及び携帯型端末器
WO2011145344A1 (fr) * 2010-05-18 2011-11-24 三洋電機株式会社 Dispositif de station de base

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003309630A (ja) * 2002-04-12 2003-10-31 Yuhshin Co Ltd 携帯送受信装置
JP2005009933A (ja) * 2003-06-17 2005-01-13 Mazda Motor Corp 走行支援システム、車載端末器及び携帯型端末器
JP2005012491A (ja) * 2003-06-19 2005-01-13 Hitachi Ltd 移動通信装置
WO2011145344A1 (fr) * 2010-05-18 2011-11-24 三洋電機株式会社 Dispositif de station de base

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7300870B2 (ja) 2018-04-06 2023-06-30 ロベルト・ボッシュ・ゲゼルシャフト・ミト・ベシュレンクテル・ハフツング 車両のためのデータレコーダ装置

Similar Documents

Publication Publication Date Title
JP5442885B2 (ja) 無線装置
WO2011152023A1 (fr) Dispositif de terminal
WO2011037161A1 (fr) Appareil de radio
JP5919541B2 (ja) 端末装置および通信システム
JP5895199B2 (ja) 無線装置
WO2011145344A1 (fr) Dispositif de station de base
JP5754998B2 (ja) 端末装置
WO2012001974A1 (fr) Dispositif formant terminal
US20120269121A1 (en) Base station apparatus for transmitting or receiving a signal including predetermined information
JP2012174216A (ja) 基地局装置
WO2013094187A1 (fr) Appareil sans fil
JP5579511B2 (ja) 端末装置
JP2015043477A (ja) 無線装置
JP2015043478A (ja) 無線装置
WO2011158484A1 (fr) Dispositif de terminal
JP2015039089A (ja) 無線装置
JP6028978B2 (ja) 端末装置
WO2013094203A1 (fr) Dispositif sans fil et dispositif de navigation
WO2012131830A1 (fr) Dispositif de terminal
JP2015039088A (ja) 無線装置
JP5830259B2 (ja) 無線装置
JP2015038663A (ja) ナビゲーション装置
JP6090631B2 (ja) 無線装置
JP2012199860A (ja) 端末装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12860559

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12860559

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP