JP2019100886A - Vehicle-purpose communication system, on-vehicle communication device and vehicle-purpose communication method - Google Patents

Abstract

To provide a vehicle-purpose communication system, on-vehicle communication device and vehicle-purpose communication method that enlarge a communication range with portable type communication devices users carry with, and can detect a location of the portable type communication device.SOLUTION: A vehicle-purpose communication system according to an embodiment of the present invention comprises: an on-vehicle communication device that transmits a radio signal, using a plurality of transmission-purpose antennas arranged in a vehicle with the antennas spaced from each other; and a portable type communication device that receives the signal transmitted from the on-vehicle communication device, and transmits a responce signal. The on-vehicle communication device is configured to simultaneously transmit the radio signals from the plurality of transmission-purposed antennas; when receiving the responce signal from the portable type communication device with respect to the simultaneously transmitted radio signals, individually transmit the radio signal sequentially from the plurality of transmission-purpose antennas; and determine a relative location of the portable type communication device to the vehicle in accordance with the response signal from the portable type communication device with respect to the sequentially transmitted radio signal.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a vehicle communication system, a vehicle-mounted communication device, and a vehicle communication method for communicating between a vehicle and a portable communication device carried by a user.

  A system for locking and unlocking a door of a vehicle without using a mechanical key has been put to practical use. For example, in the smart entry (registered trademark) system, the portable type of the user, for example, when the user carrying the portable communication device approaches the vehicle, or when the user performs an action such as gripping the door handle of the vehicle. Wireless communication is performed between the communication device and the on-vehicle communication device of the vehicle to unlock the door of the vehicle.

  In addition, the in-vehicle communication device communicates with the user's portable communication device to detect that the user is approaching the vehicle, and the on-vehicle light and the on-vehicle light provided in the vehicle are automatically set in a predetermined pattern. Welcome lights to be lit have been put to practical use. As described above, by detecting the approach of the user to the vehicle by communication with the portable communication device, it is possible to provide various convenient functions to the user before the start of traveling of the vehicle. Become.

  In patent document 1, the communication system for vehicles which can extend the reception range of the signal by a portable machine by transmitting a signal from a plurality of LF (Low Frequency) transmitting antennas arranged distantly to a vehicle to a portable machine at the same time Has been proposed.

International Publication Number WO 2017/078040

  The vehicle communication system described in Patent Document 1 needs to simultaneously transmit radio signals from a plurality of antennas provided in the vehicle in order to expand the communication range with the portable device. Therefore, there is a problem that the position of the portable device can not be detected by using a plurality of antennas.

  The present invention has been made in view of such circumstances, and the object of the present invention is to expand the communication range with the portable communication device carried by the user and to detect the position of the portable communication device. It is an object of the present invention to provide an on-vehicle communication system, an on-vehicle communication apparatus, and a on-vehicle communication method.

  The vehicular communication system according to the present aspect includes an on-vehicle communication device for transmitting a wireless signal using a plurality of transmitting antennas disposed apart from the vehicle, and a wireless signal transmitted from the on-vehicle communication device. In the vehicular communication system including a portable communication device for transmitting a response signal, the on-vehicle communication device transmits a radio signal simultaneously from the plurality of transmission antennas, and the portable communication device for the radio signal transmitted simultaneously. And a transmission processing unit that individually transmits a wireless signal sequentially from the plurality of transmission antennas when receiving a response signal from the portable communication device according to a response signal from the portable communication device to the wireless signal sequentially transmitted. And a determination unit that determines the relative position of the portable communication device with respect to the vehicle.

  The on-vehicle communication device according to the present aspect transmits a wireless signal using a plurality of transmitting antennas disposed apart from the vehicle, and receives a response signal from the portable communication device transmitted according to the wireless signal. In the on-vehicle communication device, when wireless signals are simultaneously transmitted from the plurality of transmitting antennas and a response signal from the portable communication device to the wireless signals transmitted simultaneously is received, the plurality of transmitting antennas are sequentially arranged. Determination of the relative position of the portable communication device with respect to the vehicle in response to a transmission processing unit individually transmitting a wireless signal to the mobile communication device and a response signal from the portable communication device to the wireless signal transmitted sequentially And a unit.

  A communication method for a vehicle according to this aspect comprises: an on-vehicle communication device for transmitting a wireless signal using a plurality of transmitting antennas arranged at a distance from the vehicle; and a wireless signal transmitted from the on-vehicle communication device In the vehicular communication method for communicating with a portable communication device that transmits a response signal, the on-vehicle communication device simultaneously transmits a wireless signal from the plurality of transmission antennas, and the portable communication for the wireless signal transmitted simultaneously When a response signal from the device is received, wireless signals are individually transmitted sequentially from the plurality of transmitting antennas, and the response signal from the portable communication device to the wireless signal transmitted sequentially is received according to the response signal. The relative position of the portable communication device with respect to the vehicle is determined.

  The present application can not only be realized as a vehicular communication system provided with such a characteristic control unit, but can also be realized as a vehicular communication method in which such characteristic control is taken as a step, or such a step is It can be realized as a program for execution. In addition, the present invention can be realized as a semiconductor integrated circuit that realizes a part or all of the vehicular communication system, or as another system including the vehicular communication system.

  According to the above, it is possible to provide a vehicular communication system and an on-vehicle communication device capable of detecting the position of the portable communication device while expanding the communication range with the portable communication device possessed by the user.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which shows the outline | summary of the communication system for vehicles which concerns on this embodiment. It is a block diagram showing composition of ECU concerning this embodiment. It is a block diagram which shows the structure of the portable remote control which concerns on this Embodiment. It is a timing chart for explaining the procedure of the wireless communication performed between ECU and a portable remote control. It is a flowchart which shows the procedure of the communication processing which ECU performs. It is a flowchart which shows the procedure of the communication processing which ECU performs. It is a flowchart which shows the procedure of the communication processing which a portable remote control performs. It is a timing chart for explaining the procedure of the wireless communication performed between ECU of a communications system for vehicles concerning a modification, and a portable remote control.

[Description of the embodiment of the present invention]
First, the embodiments of the present invention will be listed and described. In addition, at least part of the embodiments described below may be arbitrarily combined.

(1) The vehicular communication system according to the present aspect includes an on-vehicle communication device for transmitting a wireless signal using a plurality of transmitting antennas disposed apart from the vehicle, and a wireless signal transmitted from the on-vehicle communication device. In a vehicular communication system including a portable communication device for receiving and transmitting a response signal, the on-vehicle communication device transmits radio signals simultaneously from the plurality of transmission antennas, and the portable type for the radio signals transmitted simultaneously A transmission processing unit individually transmits a wireless signal sequentially from the plurality of transmitting antennas when receiving a response signal from the communication device, and a response signal from the portable communication device to the wireless signal transmitted sequentially And a determination unit that determines the relative position of the portable communication device with respect to the vehicle.

  In this aspect, the in-vehicle communication device transmits radio signals simultaneously from the plurality of transmission antennas, and performs wireless communication with the portable communication device in a wide communication range. When a response signal from the portable communication device is obtained in response to the transmission of the wireless signal, the on-vehicle communication device transmits the wireless signal using the plurality of transmitting antennas individually to thereby transmit the wireless communication device. Determine the position. Thus, the on-vehicle communication device can detect the approach of the user possessing the portable communication device in a wide range from the vehicle by simultaneously transmitting the wireless signals from the plurality of transmission antennas, and thereafter, for the plurality of transmissions. By individually transmitting radio signals sequentially from the antenna, it is possible to determine the position of the portable communication device approaching the vehicle.

(2) When the transmission processing unit does not receive a response signal from the portable communication device, it is preferable that the transmission processing unit periodically and repeatedly transmits the radio signals from the plurality of transmission antennas.

  In this aspect, when the portable communication device does not receive the response signal from the portable communication device, the in-vehicle communication device needs to determine the position of the portable communication device because the portable communication device does not exist within the communication range. Absent. Therefore, in the case of not receiving a response signal, the in-vehicle communication device can reduce unnecessary processing by periodically repeating the simultaneous transmission of radio signals from a plurality of transmission antennas, thereby reducing dark current. Etc can be expected.

(3) The transmission processing unit transmits a radio signal for synchronization when receiving a response signal from the portable communication device to the radio signal simultaneously transmitted from a plurality of transmission antennas, and transmits the radio signal for synchronization It is preferable to individually transmit radio signals sequentially from the plurality of transmission antennas at predetermined timing after signal transmission.

  In this aspect, after the in-vehicle communication device receives a response signal from the portable communication device, the in-vehicle communication device transmits a synchronization radio signal to notify execution of sequential radio transmission by the plurality of transmission antennas. Send. Thereafter, the on-vehicle communication device individually transmits the radio signals sequentially from the plurality of transmission antennas at predetermined timing from the transmission of the radio signal for synchronization. As a result, the portable communication device that has entered the communication range of the vehicle can be facilitated to perform processing in synchronization with the in-vehicle communication device.

(4) The portable communication device has a detection unit that detects the reception intensity of the wireless signal transmitted from the in-vehicle communication device, and after receiving the wireless signal for synchronization transmitted from the in-vehicle communication device, The detection unit repeatedly detects the reception strength at a predetermined timing, includes information on a plurality of detection results in the response signal, and transmits the response signal to the in-vehicle communication device, and the determination unit of the in-vehicle communication device Preferably, the position of the portable communication device is determined based on the information included in the response signal.

  In this aspect, the portable communication device can receive a wireless signal from the in-vehicle communication device and can detect the reception intensity. The portable communication device repeatedly detects the reception strength at a predetermined timing after receiving the synchronization radio signal transmitted by the in-vehicle communication device. As a result, the portable communication device can respectively detect the reception intensity of the wireless signal that the on-vehicle communication device individually transmits individually from the plurality of transmission antennas. The portable communication device includes information on the plurality of detection results in a response signal and transmits the response signal to the in-vehicle communication device. The in-vehicle communication device that has received the response signal from the portable communication device acquires the information related to the detection result of the reception intensity included in the response signal. For example, the in-vehicle communication device can specify the transmitting antenna that has transmitted the wireless signal determined to have the highest reception strength, and can determine that the portable communication device is present at a position close to the transmitting antenna.

(5) Preferably, the transmission processing unit simultaneously transmits the radio signal for synchronization from the plurality of transmission antennas.

  In this aspect, the on-vehicle communication device simultaneously transmits the radio signal for synchronization from the plurality of transmitting antennas. Since the reception range of the radio signal for synchronization can be expanded by this, the portable communication device can receive the radio signal for synchronization more reliably.

(6) The on-vehicle communication device according to the present aspect transmits a wireless signal using a plurality of transmitting antennas disposed apart from the vehicle, and a response from the portable communication device to be transmitted according to the wireless signal. In the on-vehicle communication device that receives a signal, the plurality of transmission antennas transmit radio signals simultaneously from the plurality of transmission antennas, and receive response signals from the portable communication device to the radio signals transmitted simultaneously. A relative position of the portable communication device with respect to the vehicle in response to a transmission processing unit that individually transmits a wireless signal sequentially from the mobile communication device and a response signal from the portable communication device to the wireless signal transmitted sequentially And a determination unit.

  In the present aspect, as in the aspect (1), the on-vehicle communication device approaches the user possessing the portable communication device in a wide range from the vehicle by simultaneously transmitting the wireless signals from the plurality of transmitting antennas. By separately transmitting radio signals sequentially from a plurality of transmitting antennas after that, it is possible to determine the position of the portable communication device that has approached the vehicle.

(7) The vehicle communication method according to this aspect comprises: an on-vehicle communication device for transmitting a wireless signal using a plurality of transmitting antennas disposed apart from the vehicle; and a wireless signal transmitted from the on-vehicle communication device In the vehicle communication method in which communication is performed with a portable communication device that receives and transmits a response signal, the in-vehicle communication device simultaneously transmits a radio signal from the plurality of transmission antennas, and the communication signal is transmitted to the simultaneously transmitted radio signal. When a response signal from the portable communication device is received, wireless signals are individually transmitted sequentially from the plurality of transmitting antennas, and a response signal from the portable communication device to the wireless signal transmitted sequentially is received. To determine the relative position of the portable communication device with respect to the vehicle.

  In the present aspect, as in the aspect (1), the vehicle communication method transmits the wireless signal from the plurality of transmission antennas at the same time to transmit the portable communication device in a wide range from the vehicle. The approach can be detected, and thereafter, by individually transmitting radio signals sequentially from a plurality of transmitting antennas, it is possible to determine the position of the portable communication device approaching the vehicle.

Details of the Embodiment of the Present Invention
A specific example of a vehicular communication system according to an embodiment of the present invention will be described below with reference to the drawings. The present invention is not limited to these exemplifications, but is shown by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

<System outline>
FIG. 1 is a schematic view showing an outline of a communication system 1 for a vehicle according to the present embodiment. The vehicular communication system 1 according to the present embodiment uses various four radio frequency (LF) transmitting antennas 4 a to 4 d and one radio frequency (RF) receiving antenna 5 provided in the vehicle 2 to transmit various radio signals. The electronic control unit (ECU) 3 that transmits and receives, and one or more portable remote controls (remote controllers) 7 that transmit and receive wireless signals to and from the ECU 3 are configured. The ECU 3 controls the operation of various electrical components mounted on the vehicle 2 based on the communication result of wireless communication using the LF transmission antennas 4 a to 4 d and the RF reception antenna 5.

  The four LF transmission antennas 4a to 4d are arranged in the tire house of each tire or in the vicinity thereof in association with the four tires of the vehicle 2, respectively. In FIG. 1, the vertical and horizontal directions of the drawing correspond to the longitudinal and lateral directions of the vehicle 2, the LF transmission antenna 4a is disposed on the right front side of the vehicle 2, and the LF transmission antenna 4b is disposed on the right rear side. The transmitting antenna 4c is disposed on the left rear side, and the LF transmitting antenna 4d is disposed on the left front side. The LF transmission antennas 4 a to 4 d are connected to the ECU 3 disposed at an appropriate position of the vehicle 2 via signal lines. The LF transmission antennas 4a to 4d are antennas used when the ECU 3 transmits a radio signal of the LF band. The RF receiving antenna 5 is an antenna used when the ECU 3 receives a radio signal in the UHF (Ultra High Frequency) band.

  The vehicular communication system 1 according to the present embodiment may have a function of monitoring the air pressure of the tire of the vehicle 2, that is, the so-called TPMS (Tire Pressure Monitoring System). In this case, each tire of the vehicle 2 is attached with a sensor unit having a function of air pressure detection of the tire and wireless communication. The ECU 3 transmits a radio signal to the sensor unit of each tire by the LF transmission antennas 4a to 4d, and receives a response from the sensor unit by the RF reception antenna 5. The ECU 3 acquires the detection result of the air pressure of the tire included in the response from each sensor unit, and displays the detection result of the air pressure of the tire on a display provided in the vicinity of the driver's seat of the vehicle 2, for example When the value of V falls below the threshold value, processing such as issuing a warning is performed.

  The vehicular communication system 1 according to the present embodiment determines whether or not the portable remote controller 7 possessed by the user is present in the vicinity of the vehicle 2 and determines the relative position of the portable remote controller 7 with respect to the vehicle 2. Do. Thereby, the communication system 1 for vehicles can perform the process which unlocks the lock of the door of the vehicle 2 according to the approach of the portable remote control 7, or the process which lights the interior light and the exterior light of the vehicle 2, etc.

  In a situation where the portable remote controller 7 is not present around the vehicle 2, the ECU 3 periodically (for example, with a period of several hundreds of milliseconds to several seconds) transmits radio signals of the LF band from the LF transmission antennas 4a to 4d. The ECU 3 determines whether or not the portable remote controller 7 is within the communication range of the wireless communication by determining whether or not the response signal from the portable remote controller 7 to this signal transmission is received by the RF receiving antenna 5; It is determined whether or not the portable remote controller 7 exists around the vehicle 2. At this time, the ECU 3 simultaneously (simultaneously) transmits radio signals from the plurality of LF transmission antennas 4a to 4d. The radio signals transmitted from the plurality of LF transmission antennas 4a to 4d expand their reach by being superimposed. The simultaneous transmission of the radio signals by the plurality of LF transmission antennas 4a to 4d may be performed by superimposing and amplifying the plurality of radio signals, as long as the reach range is widened, and some error is tolerated.

  In the present embodiment, the ECU 3 performs processing alternately on the right side and the left side of the vehicle 2. That is, the ECU 3 transmits radio signals by the LF transmission antennas 4a and 4b on the right side of the vehicle 2 to determine the presence or absence of the portable remote controller 7, and then transmits radio signals by the LF transmission antennas 4c and 4d on the left side It is determined whether the remote control 7 is present. The ECU 3 periodically and repeatedly performs the left and right alternate determination as in the determination on the right side, the determination on the left side, the determination on the right side, the determination on the left side, and so on. In the following description, details will be described focusing on the process related to the right side of the vehicle 2, but the process related to the left side is the same, so detailed description will be omitted.

  The reach of the radio signal when the ECU 3 simultaneously transmits the radio signal from the two LF transmission antennas 4a and 4b, that is, the communicable range of the ECU 3 and the portable remote controller 7 is shown as a region A of a dashed dotted line in FIG. Further, FIG. 1 shows a communicable range when the ECU 3 transmits a radio signal from only the LF transmission antenna 4a as a region B1 of a broken line, and a communicable range when the ECU 3 transmits a radio signal only from the LF transmission antenna 4b. Is shown as a dashed area B2. The position of the portable remote controller 7 shown in FIG. 1 can receive this radio signal when the ECU 3 simultaneously transmits radio signals from the two LF transmission antennas 4a and 4b, but only one of the LF transmission antennas 4a and 4b When the wireless signal is transmitted from the position, the wireless signal can not be received.

  When the ECU 3 simultaneously transmits radio signals from the two LF transmission antennas 4a and 4b, and the portable remote controller 7 exists in the communicable range A, the portable remote controller 7 receives the radio signal from the ECU 3. The portable remote controller 7 having received the LF band radio signal from the ECU 3 generates a response signal including information such as identification information or authentication information, and transmits the response signal as a UHF band radio signal. The ECU 3 receives a response signal transmitted as a wireless signal in the UHF band from the portable remote controller 7 to the RF receiving antenna 5, and the portable remote controller 7 of the transmission source is associated with the vehicle 2 based on the information included in the response signal. It is determined whether or not the When the portable remote controller 7 is a legitimate one, the ECU 3 determines that the portable remote controller 7 exists near the vehicle 2 (within the communicable range A). Note that the vehicle communication system 1 may be configured to transmit and receive radio signals several times in order to perform authentication processing between the ECU 3 and the portable remote controller 7.

  The ECU 3 that has determined that the portable remote control 7 exists near the vehicle 2 performs processing of determining the position of the portable remote control 7. At this time, the ECU 3 simultaneously transmits radio signals for synchronization from the two LF transmission antennas 4a and 4b in order to notify the portable remote controller 7 that the processing of position determination is to be started. Thereafter, the ECU 3 transmits a radio signal using only the LF transmission antenna 4a on the right front side after a predetermined time has elapsed since the transmission of the radio signal for synchronization, and after a predetermined period of time elapses, only the LF transmission antenna 4b on the right rear side Use to transmit wireless signals.

  The portable remote controller 7 has a function of detecting the reception intensity of the radio signal when the radio signal of the LF band transmitted from the LF transmission antennas 4 a to 4 d of the vehicle 2 is received. When the portable remote controller 7 receives the wireless signal for synchronization transmitted by the ECU 3, the portable remote controller 7 detects the signal strength of the wireless signal received after a predetermined time has elapsed from the reception of the wireless signal for synchronization, and further receives the wireless signal after a predetermined period Detect the signal strength of the signal. After completing the two detections, the portable remote controller 7 transmits to the ECU 3 a response signal including the two detection results.

  The ECU 3 receiving the response signal from the portable remote controller 7 by the RF receiving antenna 5 acquires the detection result included in the response signal. The ECU 3 determines which one of the LF transmission antennas 4a and 4b is closer to the portable telephone remote control 7 based on the detection result of the reception intensity of the wireless signal from each LF transmission antenna 4a or 4b in the portable remote controller 7 And the relative position of the portable remote 7 to the vehicle 2 can be determined. The position of the portable remote controller 7 determined by the ECU 3 may not be a detailed position such as a point of X meters from the vehicle 2, but may be an approximate position such as diagonally right front of the vehicle 2.

  Although FIG. 1 illustrates that the communicable ranges B1 and B2 in the case where the radio signal is transmitted using only one of the LF transmission antennas 4a and 4b do not overlap, there is actually an overlapping portion. there is a possibility. Even in such a case, the ECU 3 accurately determines the position of the portable remote controller 7 by notifying the ECU 3 of the reception intensity of the wireless signal transmitted from each LF transmission antenna 4a, 4b. Is possible.

<Device configuration>
FIG. 2 is a block diagram showing the configuration of the ECU 3 according to the present embodiment. The ECU 3 according to the present embodiment includes a processing unit (processor) 30, a storage unit (storage) 31, an LF transmission unit 32, an RF reception unit 33, an input unit 34, an in-vehicle communication unit 35, and the like. The processing unit 30 is configured using an arithmetic processing unit such as a central processing unit (CPU) or a micro-processing unit (MPU), and reads and executes the program 31 a stored in the storage unit 31 to perform various operations. Processing and control processing can be performed. In the present embodiment, the processing unit 30 performs, for example, communication processing with the portable remote controller 7, position determination processing of the portable remote controller 7, and the like. The processing unit 30 may also perform lock control processing of the door of the vehicle 2 according to the communication with the portable remote controller 7, and lighting control processing of the interior light and the exterior light. Furthermore, the processing unit 30 can also perform processing related to TPMS, for example, communication processing with the sensor unit of each tire, determination processing of the tire pressure of the tire, and notification processing of the determination result.

  The storage unit 31 is configured using, for example, a non-volatile memory element such as a flash memory or an EEPROM (Electrically Erasable Programmable Read Only Memory). The storage unit 31 stores various programs 31 a executed by the processing unit 30 and various data necessary for the processing of the processing unit 30. Further, the processing unit 30 may store various data generated in the processing process in the storage unit 31.

  The LF transmitter 32 has four LF transmitter antennas 4a to 4d connected via signal lines. The LF transmission unit 32 modulates digital transmission data supplied from the processing unit 30, and outputs the modulated signal to the LF transmission antennas 4a to 4d to transmit an LF band radio signal. Further, the LF transmitter 32 can arbitrarily select to which of the four LF transmission antennas 4a to 4d the signal is to be output, and simultaneously transmits radio signals from a plurality of LF transmission antennas 4a to 4d. The radio signals can be transmitted from only one LF transmitting antenna 4a to 4d. The RF reception unit 33 receives a radio signal in the UHF band at the RF reception antenna 5 and applies digital reception data obtained by demodulating the received radio signal to the processing unit 30.

  The input unit 34 receives input of signals from various electrical components provided in the vehicle 2 and gives the received input signal to the processing unit 30 as digital input data. In the present embodiment, a signal from an IG (ignition) switch 61 of the vehicle 2 and a signal from a door switch 62 provided on each door of the vehicle 2 are input to the input unit 34. The IG switch 61 inputs an IG signal indicating the operating state of the engine of the vehicle 2 to the ECU 3. The door switch 62 detects an opening operation of the user with respect to the door of the vehicle 2 and inputs a signal to notify the presence or absence of the opening operation to the ECU 3.

  The in-vehicle communication unit 35 is connected to a communication line disposed in the vehicle 2 and can communicate with other in-vehicle devices via the communication line. The in-vehicle communication unit 35 can be configured to perform communication in accordance with, for example, a CAN (Controller Area Network) communication protocol. The in-vehicle communication unit 35 transmits the message by converting the transmission message supplied from the processing unit 30 into an electric signal and outputting the electric signal to the communication line. Further, the in-vehicle communication unit 35 receives a message by sampling and acquiring the potential of the communication line, and gives the received message to the processing unit 30. In the present embodiment, the lighting ECU 63, the door ECU 64, and the like are connected to the ECU 3 via a communication line.

  The lighting ECU 63 is connected to a plurality of interior lights and exterior lights mounted on the vehicle 2 and controls lighting and extinguishing of these. The control target of the lighting ECU 63 may be, for example, an existing light emitting unit such as a headlamp of the vehicle 2, a tail lamp, a direction indicator, a hazard lamp, and a room lamp. In the present embodiment, the control target of the lighting ECU 63, as the light emitting portion for the welcome light, illuminates the front, the rear, the side, the right diagonal front, the left diagonal front, the right diagonal rear and the left diagonal rear of the vehicle 2 exceptionally. Let it be a light emitting part. The ECU 3 can control lighting and extinguishing of the light emitting units by giving an instruction of lighting or extinguishing each light emitting unit to the lighting ECU 63 through communication by the in-vehicle communication unit 35.

  The door ECU 64 drives a lock mechanism that locks and unlocks the door of the vehicle 2. The ECU 3 can control locking / unlocking of the door of the vehicle 2 by giving an instruction to the door ECU 64 by communication by the in-vehicle communication unit 35. For example, when the door switch 62 provided at the door of the vehicle 2 is operated, the ECU 3 performs wireless communication with the portable remote controller 7, succeeds in the authentication of the portable remote controller 7, and the portable remote controller 7 exists around the vehicle 2. If it is determined that the door ECU 64 determines that the door ECU 64 is locked or unlocked. Further, for example, the ECU 3 determines the position of the portable remote controller 7 when the door of the vehicle 2 is opened and closed with the IG switch 61 turned off, and a locking instruction is issued to the door ECU 64 when the portable remote controller 7 is separated from the vehicle 2 It may be sent to. When the door ECU 64 receives a locking or unlocking command from the ECU 3, the door ECU 64 drives the locking mechanism to lock or unlock the door of the vehicle 2. Further, the door ECU 64 locks or unlocks the door of the vehicle 2 by driving the lock mechanism according to the operation of the locking / unlocking switch provided in the vehicle, and the information indicating the locking / unlocking state of the door of the vehicle 2 is It transmits to ECU3 by communication. The ECU 3 can recognize the locking / unlocking state of the door of the vehicle 2 by receiving the information transmitted from the door ECU 64 by the in-vehicle communication unit 35.

  Further, in the ECU 3 according to the present embodiment, the processing unit 30 reads out and executes the program 31a stored in the storage unit 31 so that the communication processing unit 41, the position determination unit 42, etc. It is realized as a block. The communication processing unit 41 performs wireless communication with the portable remote controller 7 by exchanging commands and information with the LF transmission unit 32 and the RF reception unit 33. For example, the communication processing unit 41 causes the LF transmission unit 32 to periodically transmit a wireless signal, and determines whether the RF reception unit 33 has received a response signal to the wireless signal. A process is performed to determine whether the remote control 7 is present. When the communication processing unit 41 receives a response signal from the portable remote controller 7, the communication processing unit 41 performs processing to determine whether the portable remote controller 7 is legitimate or not based on the information included in the response signal. The communication processing unit 41 performs processing to control which one of the four LF transmission antennas 4 a to 4 d is used when transmitting a wireless signal by the LF transmission unit 32.

  The position determination unit 42 individually (in order) sequentially transmits the radio signals in the LF transmission unit 32 using the plurality of LF transmission antennas 4a to 4d, and the response signal transmitted from the portable remote control 7 in response thereto. Is received by the RF receiving unit 33, and processing for determining the position of the portable remote controller 7 based on the information contained in the received response signal is performed. In the present embodiment, the portable remote controller 7 detects the reception strength of the wireless signal, calculates the distance from the LF transmission antennas 4 a to 4 d of the transmission source based on the detected reception strength, and uses the calculated distance information as a response signal. It transmits to ECU3 including. The position determination unit 42 calculates the position of the portable remote controller 7 based on the distance information from each of the LF transmission antennas 4 a to 4 d included in the response signal from the portable remote controller 7. For example, when the position determination unit 42 acquires distance information that the distance from the LF transmission antenna 4a is a meter and the distance from the LF transmission antenna 4b is b meters, the radius around the position of the LF transmission antenna 4a The position of the portable remote controller 7 can be calculated by calculating the coordinates of the point of intersection of the circle of a meter and the circle of radius b meter centered on the position of the LF transmission antenna 4b.

  FIG. 3 is a block diagram showing the configuration of the portable remote controller 7 according to the present embodiment. The portable remote controller 7 according to the present embodiment includes a control unit 70, a storage unit 71, an LF reception unit 72, an intensity detection unit 73, an RF transmission unit 74, and the like. The control unit 70 realizes wireless communication between the ECU 3 of the vehicle 2 and the portable remote controller 7 by controlling the operation of each part of the portable remote controller 7. The storage unit 71 is configured using, for example, a non-volatile memory element such as an EEPROM or a mask ROM (Read Only Memory). The storage unit 71 stores various data necessary for the process performed by the control unit 70. For example, the storage unit 71 stores authentication information 71 a necessary for an authentication process with the ECU 3 of the vehicle 2. The authentication information 71a can be, for example, information such as identification information of the portable remote controller 7, a password, and an encryption key.

  The LF reception unit 72 is connected to the LF reception unit 72. The LF reception unit 72 supplies digital reception data obtained by demodulating the radio signal of the LF band received by the LF reception antenna 7 a to the control unit 70. The intensity detection unit 73 is connected to the LF reception antenna 7a, detects the intensity (for example, amplitude) of the LF band radio signal received by the LF reception antenna 7a, and notifies the detected intensity to the control unit 70. . The RF transmission unit 74 is connected to the RF transmission antenna 7b. The RF transmission unit 74 transmits a radio signal in the RF band by outputting a signal obtained by modulating the data for transmission given from the control unit 70 to the RF transmission antenna 7 b.

  Control unit 70 of portable remote controller 7 according to the present embodiment includes authentication information 71a stored in storage unit 71 when the LF reception unit 72 receives a radio signal of the LF band transmitted by ECU 3 of vehicle 2 Transmission data for response is generated and supplied to the RF transmission unit 74. At this time, the portable remote controller 7 performs an authentication process to determine whether the received radio signal in the LF band is from the legitimate vehicle 2 and for response only when it is determined to be the legitimate one. Transmission data may be generated. However, in the present embodiment, the description of the authentication process by the portable remote controller 7 is omitted. The RF transmission unit 74 to which transmission data for response is given from the control unit 70 modulates this and outputs it to the RF transmission antenna 7 b to transmit a response signal in the UHF band to the vehicle 2.

  In addition, when the control unit 70 of the portable remote control 7 receives the wireless signal for synchronization from the vehicle 2 at the LF receiving unit 72 after transmitting the above-mentioned response signal, the detection of the reception intensity by the intensity detecting unit 73 is started Do. The control unit 70 causes the intensity detection unit 73 to perform intensity detection a predetermined number of times at a predetermined timing from the reception of the radio signal for synchronization, and acquires the detection result. In the present embodiment, the strength detection is performed twice at a predetermined timing from the reception of the radio signal for synchronization, and the control unit 70 acquires the detection results for two times. The control unit 70 calculates distance information based on the reception intensity which is the detection result. The calculation of the distance information from the reception strength may be performed using, for example, a predetermined arithmetic expression, or, for example, a table indicating the correspondence between the reception strength and the distance information is stored in the storage unit 71. It may be calculated with reference. The control unit 70 generates response data including two pieces of distance information calculated from the reception strengths for two times, gives the data to the RF transmission unit 74, and transmits a response signal including the two pieces of distance information.

<Communication procedure>
FIG. 4 is a timing chart for explaining the procedure of wireless communication performed between the ECU 3 and the portable remote controller 7. The ECU 7 periodically transmits a radio signal from the LF transmission antennas 4a and 4b on the right front side and the right rear side (see "entire transmission" in FIG. 4) periodically until the response signal from the portable remote control 7 is obtained. It has been repeated. When the portable remote control 7 exists in the communicable range A when the radio signals are simultaneously transmitted from the two LF transmission antennas 4a and 4b, the portable remote control 7 receives the radio signal from the vehicle 2, and receives the authentication information 71a and the like. A response signal including is sent to the vehicle 2.

  The ECU 3 having received the response signal from the portable remote controller 7 determines whether the portable remote controller 7 is legitimate or not based on the authentication information included in the response signal. If it is determined that the portable remote controller 7 is correct, the ECU 3 simultaneously transmits a radio signal for synchronization from the two LF transmission antennas 4a and 4b (see "overall transmission for synchronization" in FIG. 4). Furthermore, the ECU 3 individually transmits a radio signal from the LF transmission antenna 4a on the right front side after a predetermined time T1 has elapsed since the transmission of a radio signal for synchronization, and further, LF transmission on the right rear side after a predetermined time T2 Radio signals are individually transmitted from the antenna 4b.

  The portable remote controller 7 having received the radio signal for synchronization from the ECU 3 does not immediately transmit a response signal thereto, but transmits a response signal after performing two reception intensity detections. The portable remote controller 7 receives a radio signal transmitted from the ECU 3 at the LF reception unit 72 after a predetermined time T1 has elapsed since receiving the radio signal for synchronization, and the strength detection unit 73 for the radio signal is received. Detect the intensity by Furthermore, after a predetermined time T2 has elapsed since the first intensity detection, the portable remote controller 7 similarly performs the second intensity detection. The portable remote controller 7 calculates distance information based on the reception intensity obtained by the intensity detection, and transmits the response information including the distance information for two times to the ECU 3.

  The ECU 3 having received the response signal from the portable remote controller 7 acquires two pieces of distance information included in the response signal. The ECU 3 determines the relative position of the portable remote controller 7 with respect to the vehicle 2 based on the acquired two pieces of distance information. The ECU 3 and the portable remote controller 7 store in advance values common to the predetermined times T1 and T2 that define the timing of transmission and reception. The predetermined times T1 and T2 can be, for example, several hundred milliseconds.

  FIG.5 and FIG.6 is a flowchart which shows the procedure of the communication processing which ECU3 performs. However, since this flowchart shows the procedure of the communication processing regarding the right side of the vehicle 2 and the communication processing regarding the left side is the same, the detailed procedure is omitted. The communication processing unit 41 of the processing unit 30 of the ECU 3 according to the present embodiment transmits a radio signal simultaneously from the two LF transmission antennas 4a and 4b on the right front side and the right rear side by giving an instruction to the LF transmission unit 32. To do (step S1). The communication processing unit 41 determines whether the RF receiving unit 33 receives a response signal from the portable remote controller 7 (step S2).

  When the response signal from the portable remote controller 7 is not received (S2: NO), the communication processing unit 41 stands by for a predetermined time by counting using the timer function in the processing unit 30 (step S10). The predetermined time defines a cycle in which the ECU 3 confirms the presence or absence of the portable remote controller 7, and for example, a time of several hundred milliseconds to several seconds is set in advance. After the predetermined time has elapsed, the ECU 3 performs communication processing on the left side of the vehicle 2 (step S11), and returns the process to step S1.

  When the response signal from the portable remote controller 7 is received (S2: YES), the communication processing unit 41 determines whether the portable remote controller 7 is legitimate or not based on the authentication information included in the response signal. A process is performed (step S3), and it is determined whether the authentication is successful (step S4). If the authentication fails (S4: NO), that is, if the portable remote controller 7 is not the correct one, the communication processing unit 41 stands by for a predetermined time (step S10) and performs communication processing on the left side of the vehicle 2 (step S10) S11), the process returns to step S1.

  If the authentication is successful (S4: YES), that is, if the portable remote control 7 is legitimate, the communication processing unit 41 gives an instruction to the LF transmission unit 32 to set the two LFs on the right front side and the right back side. A radio signal for synchronization is simultaneously transmitted from the transmitting antennas 4a and 4b (step S5). Next, the communication processing unit 41 waits for a predetermined time T1 from the transmission of the synchronization radio signal (step S6). After the predetermined time T1 has elapsed, the communication processing unit 41 individually transmits a radio signal from the LF transmission antenna 4a on the right front side by giving an instruction to the LF transmission unit 32 (step S7). Next, the communication processing unit 41 stands by for a predetermined time T2 (step S8). After the predetermined time T2 has elapsed, the communication processing unit 41 individually transmits a radio signal from the LF transmission antenna 4b on the right rear side by giving an instruction to the LF transmission unit 32 (step S9).

  Thereafter, the communication processing unit 41 determines whether or not the response signal from the portable remote controller 7 has been received by the RF receiving unit 33 (step S12). If the response signal has not been received (S12: NO), the communication processing unit 41 stands by for a predetermined time (step S10), performs communication processing on the left side of the vehicle 2 (step S11), and proceeds to step S1. return. When the response signal is received (S12: YES), the communication processing unit 41 acquires two pieces of distance information included in the response signal (step S13). The position determination unit 42 of the processing unit 30 determines the position of the portable remote controller 7 based on the two pieces of distance information acquired in step S13 (step S14). The processing unit 30 performs control to turn on the light emitting unit of the vehicle 2 mounted at the corresponding position based on the position of the portable remote controller 7 determined in step S14 (step S15), and ends the process.

  FIG. 7 is a flowchart showing the procedure of communication processing performed by the portable remote controller 7. The control unit 70 of the portable remote controller 7 determines whether the radio frequency signal transmitted by the ECU 3 of the vehicle 2 has been received by the LF reception unit 72 (step S31). When the wireless signal is not received (S31: NO), the control unit 70 stands by until the wireless signal is received. When the wireless signal is received (S31: YES), the control unit 70 transmits a response signal including the authentication information 71a stored in the storage unit 71 from the RF transmission unit 74 (step S32).

  Next, the control unit 70 determines whether the LF reception unit 72 has received the synchronization wireless signal transmitted by the ECU 3 (step S33). When the radio signal for synchronization is not received (S33: NO), the control unit 70 returns the process to step S31. When the radio signal for synchronization is received (S33: YES), the control unit 70 waits for a predetermined time T1 from the reception of the radio signal for synchronization (step S34). After the predetermined time T1 has elapsed, the control unit 70 causes the LF reception unit 72 to receive the wireless signal from the ECU 3 and causes the intensity detection unit 73 to detect the reception intensity (step S35). Next, the control unit 70 waits for a predetermined time T2 after the first intensity detection (step S36). After the predetermined time T2 has elapsed, the control unit 70 causes the LF reception unit 72 to receive the wireless signal from the ECU 3 and causes the intensity detection unit 73 to detect the reception intensity (step S37).

  Next, the control unit 70 calculates distance information based on the reception intensity detected in steps S35 and S37 (step S38). The control unit 70 transmits a response signal including the calculated two pieces of distance information from the RF transmission unit 74 to the ECU 3 (step S39), and ends the process.

<Summary>
The vehicular communication system 1 according to the present embodiment having the above configuration performs wireless communication with the portable remote controller 7 in a wide communication range by the ECU 3 simultaneously transmitting wireless signals from the plurality of LF transmission antennas 4a to 4d. be able to. When a response signal from the portable remote controller 7 is obtained in response to the transmission of the wireless signal, the ECU 3 transmits the wireless signal using the plurality of LF transmission antennas 4a to 4d individually, thereby the position of the portable remote controller 7 Determine As a result, the ECU 3 can detect the approach of the portable remote controller 7 in a wide range from the vehicle 2 by simultaneous transmission of the radio signals using the plurality of LF transmission antennas 4a to 4d, and thereafter the plurality of LF transmission antennas 4a to 4d By individually transmitting the wireless signals sequentially from the above, it is possible to determine the position of the portable remote controller 7 that has approached the vehicle 2.

  When the ECU 3 does not receive the response signal from the portable remote controller 7, the portable remote controller 7 does not exist within the communicable range A, and therefore, it is not necessary to determine the position of the portable remote controller 7. Therefore, when the ECU 3 does not receive the response signal, the ECU 3 periodically and repeatedly transmits the radio signals from the plurality of LF transmission antennas 4a to 4d. As a result, unnecessary processing by the ECU 3 can be reduced, and reduction of dark current can be expected.

  Further, after the response signal from the portable remote controller 7 is obtained, the ECU 3 transmits a wireless signal for synchronization in order to notify execution of sequential wireless transmission by the plurality of LF transmission antennas 4a to 4d. Thereafter, the ECU 3 individually and sequentially transmits the radio signals from the plurality of LF transmission antennas 4a to 4d at predetermined timing after the transmission of the radio signal for synchronization. As a result, the portable remote controller 7 that has entered the communicable range A with the vehicle 2 can be easily processed in synchronization with the ECU 3.

  Further, the portable remote controller 7 receives a wireless signal from the ECU 3 of the vehicle 2, and the intensity detection unit 73 detects the reception intensity. After receiving the radio signal for synchronization from the ECU 3, the portable remote controller 7 repeatedly detects the reception intensity at a predetermined timing. Thereby, the portable remote controller 7 can respectively detect the reception intensity of the radio signal which the ECU 3 individually and sequentially transmits from the plurality of LF transmission antennas 4a to 4d. The portable remote controller 7 includes information on a plurality of detection results in a response signal and transmits the response signal to the ECU 3. The ECU 3 having received the response signal from the portable remote controller 7 acquires the information included in the response signal, and determines the position of the portable remote controller 7 based on the acquired information.

  Further, the ECU 3 simultaneously transmits, from the plurality of LF transmission antennas 4a to 4d, radio signals for synchronization to be transmitted to the portable remote controller 7. As a result, the reception range of the synchronization radio signal can be expanded, so that the portable remote controller 7 can receive the synchronization radio signal more reliably.

  With the above configuration, the vehicular communication system 1 according to the present embodiment can expand the communicable range between the ECU 3 and the portable remote controller 7 possessed by the user, and the ECU 3 detects the position of the portable remote controller 7. Can.

  In the present embodiment, although the LF transmitting antennas 4a to 4d and the RF receiving antenna 5 for performing the wireless communication with the portable remote controller 7 are shared by the ECU 3 with the wireless communication with the TPMS sensor unit, It is not limited to this. Apart from the antenna for the TPMS, the LF transmitting antennas 4 a to 4 d and the RF receiving antenna 5 may be provided for the ECU 3 to perform wireless communication with the portable remote controller 7. Further, TPMS may not be mounted on the vehicle 2.

  In the vehicle communication system 1 according to the present embodiment, the ECU 3 transmits the radio signal for synchronization before individually transmitting the radio signals from the plurality of LF transmission antennas 4a to 4d sequentially. Not limited to this. The configuration may be such that the ECU 3 does not transmit the radio signal for synchronization. In this case, for example, the timing at which the ECU 3 simultaneously transmits radio signals from a plurality of LF transmission antennas 4a to 4d, or the timing at which the ECU 3 receives a response signal from the portable remote control 7 to this radio signal The individual transmission can be started after the lapse of time.

  The portable remote controller 7 calculates the distance based on the reception intensity detected by the intensity detection unit 73, includes distance information in the response signal, and transmits the response signal to the ECU 3. However, the present invention is not limited thereto. The portable remote controller 7 may be configured to include the detected reception intensity in a response signal and transmit the response signal to the ECU 3, and the ECU 3 having received this may calculate the distance based on the reception intensity. The portable remote controller 7 may be configured to determine only the presence or absence of reception and notify the ECU 3 without determining the reception intensity.

  In the vehicle communication system 1 according to the present embodiment, the four LF transmission antennas 4a to 4d provided on the vehicle 2 are divided into two LF transmission antennas 4a and 4b on the left side and two LF transmission antennas 4c on the right side, Although divided into 4 d and configured to perform processing such as wireless communication with the portable remote controller 7 and position determination alternately on the right and left sides of the vehicle 2, the present invention is not limited to this. For example, the processing may be performed by dividing the four LF transmission antennas 4a to 4d into the front side and the rear side of the vehicle 2, and for example, as shown in the following modification, the four LF transmission antennas 4a to 4d may be left and right You may process without dividing.

(Modification)
FIG. 8 is a timing chart for explaining the procedure of wireless communication performed between the ECU 3 and the portable remote controller 7 of the communication system 1 for a vehicle according to the modification. The ECU 7 of the vehicle communication system 1 according to the modification periodically and repeatedly performs the process of simultaneously transmitting radio signals from the four LF transmission antennas 4a to 4d until a response signal from the portable remote controller 7 is obtained. When the portable remote controller 7 exists within the receivable range of the wireless signal, the portable remote controller 7 receives the wireless signal from the vehicle 2 and transmits a response signal including the authentication information 71 a and the like to the vehicle 2.

  The ECU 3 having received the response signal from the portable remote controller 7 determines whether the portable remote controller 7 is legitimate or not based on the authentication information included in the response signal. If it is determined that the portable remote controller 7 is a legitimate one, the ECU 3 simultaneously transmits radio signals for synchronization from the four LF transmission antennas 4a to 4d. Furthermore, the ECU 3 individually transmits a radio signal from the LF transmission antenna 4a on the right front side after a predetermined time T1 has elapsed since the transmission of a radio signal for synchronization, and further, LF transmission on the right rear side after a predetermined time T2 The radio signal is individually transmitted from the antenna 4b, and the radio signal is separately transmitted from the LF transmission antenna 4c on the left rear side after a predetermined time T3 elapses, and the LF transmission antenna on the left front side after a predetermined time T4 Transmit individual radio signals from 4d.

  The portable remote controller 7 having received the radio signal for synchronization from the ECU 3 does not immediately transmit a response signal thereto, but transmits a response signal after performing four reception strength detections. The portable remote controller 7 receives a radio signal transmitted from the ECU 3 at the LF reception unit 72 after a predetermined time T1 has elapsed since receiving the radio signal for synchronization, and the strength detection unit 73 for the radio signal is received. Detect the intensity by After a predetermined time T2 has elapsed from the first intensity detection, the portable remote controller 7 similarly performs the second intensity detection. Furthermore, the portable remote controller 7 performs a third intensity detection after a predetermined time T3 has elapsed since the second intensity detection, and performs a fourth intensity detection after a predetermined time T4 has elapsed since the third intensity detection. The portable remote controller 7 calculates the distance based on the reception intensity obtained by the intensity detection, and transmits the response information including the distance information for four times to the ECU 3.

  The ECU 3 having received the response signal from the portable remote controller 7 acquires four pieces of distance information included in the response signal. The ECU 3 determines the relative position of the portable remote controller 7 with respect to the vehicle 2 based on the acquired four pieces of distance information. In addition, ECU3 and the portable remote control 7 have memorize | stored beforehand the common value for the predetermined time T1-T4 which prescribes | regulates the timing of transmission / reception.

1 communication system for vehicle 2 vehicle 3 ECU (vehicle-mounted communication device)
4a to 4d LF transmission antenna (transmission antenna)
5 RF Reception Antenna 7 Mobile remote control (portable communication device)
7a LF reception antenna 7b RF transmission antenna 30 processing unit 31 storage unit 31a program 32 LF transmission unit 33 RF reception unit 34 input unit 35 in-vehicle communication unit 41 communication processing unit 42 position determination unit (determination unit)
61 IG switch 62 door switch 63 lighting ECU
64 door ECU
70 control unit 71 storage unit 71a authentication information 72 LF reception unit 73 strength detection unit (detection unit)
74 RF transmitter

Claims (7)

An on-vehicle communication device for transmitting a wireless signal using a plurality of transmitting antennas arranged at a distance from a vehicle, a portable communication device for receiving a wireless signal transmitted from the on-vehicle communication device and transmitting a response signal In a vehicle communication system comprising
The in-vehicle communication device is
When wireless signals are simultaneously transmitted from the plurality of transmitting antennas and a response signal from the portable communication device to the transmitted wireless signals simultaneously is received, the wireless signals are individually transmitted sequentially from the plurality of transmitting antennas A transmission processing unit that
And a determination unit that determines the relative position of the portable communication device with respect to the vehicle according to a response signal from the portable communication device to a wireless signal transmitted sequentially. system. When the transmission processing unit does not receive the response signal from the portable communication device, the transmission processing unit periodically and repeatedly transmits the radio signals from the plurality of transmission antennas. The communication system for vehicles as described. The transmission processing unit
When a response signal from the portable communication device to a radio signal simultaneously transmitted from a plurality of transmitting antennas is received, a radio signal for synchronization is transmitted,
The communication system for a vehicle according to claim 1 or 2, wherein the wireless signals are individually transmitted sequentially from the plurality of transmitting antennas at predetermined timing from the transmission of the wireless signal for synchronization. The portable communication device has a detection unit that detects the reception intensity of the wireless signal transmitted from the in-vehicle communication device, and a predetermined timing is received after the wireless communication signal for synchronization transmitted from the in-vehicle communication device is received. The detection unit repeatedly detects the reception strength by the detection unit, and transmits information including a plurality of detection results in the response signal to the in-vehicle communication device.
The communication system for a vehicle according to claim 3, wherein the determination unit of the in-vehicle communication device determines the position of the portable communication device based on the information included in the response signal. 5. The communication system for a vehicle according to claim 3, wherein the transmission processing unit simultaneously transmits the radio signal for synchronization from the plurality of transmission antennas. In an on-vehicle communication device, which transmits a wireless signal using a plurality of transmitting antennas arranged at a distance from a vehicle and receives a response signal from a portable communication device transmitted according to the wireless signal,
When wireless signals are simultaneously transmitted from the plurality of transmitting antennas and a response signal from the portable communication device to the transmitted wireless signals simultaneously is received, the wireless signals are individually transmitted sequentially from the plurality of transmitting antennas A transmission processing unit that
A determination unit that determines the relative position of the portable communication device with respect to the vehicle according to a response signal from the portable communication device to a wireless signal transmitted sequentially; . An on-vehicle communication device for transmitting a wireless signal using a plurality of transmitting antennas arranged at a distance from a vehicle, a portable communication device for receiving a wireless signal transmitted from the on-vehicle communication device and transmitting a response signal In the vehicle communication method in which the communication is performed,
The in-vehicle communication device is
Simultaneously transmitting radio signals from the plurality of transmitting antennas;
When a response signal from the portable communication device to the wireless signal transmitted simultaneously is received, the wireless signals are individually transmitted sequentially from the plurality of transmitting antennas,
A communication method for a vehicle, comprising: determining a relative position of the portable communication device with respect to the vehicle according to a response signal from the portable communication device to a wireless signal transmitted sequentially.

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