JP2019056636A - Portable machine position estimation system - Google Patents

Abstract

To provide a portable machine position estimation system capable of estimating a concrete position of a portable machine relative to a vehicle.SOLUTION: An on-vehicle system 100 transmits a response request signal to a portable machine 200 by using LF-band radio waves. The portable machine 200 returns a response signal including RSSI of the received response request signal by using UHF-band radio waves. The on-vehicle system 100 is configured so as to receive a response signal from the portable machine 200 by a relay antenna, and estimates a direction in which the portable machine 200 exists, based on a reception situation of the relay antenna. On the basis of the RSSI of the response request signal in the portable machine included in the response signal, distance to the portable machine is estimated. The on-vehicle system 100 estimates a position of the portable machine 200, based on directions of the portable machines and distance.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a portable device position estimation system that estimates the position of a portable device with respect to a vehicle.

  Conventionally, an in-vehicle device mounted on a vehicle and a portable device carried by a user perform an authentication process by wireless communication, and based on the establishment of the authentication process, the on-vehicle device locks and unlocks the vehicle door and engine There is a system (so-called vehicle electronic key system) that executes vehicle control such as starting. Generally, in this type of electronic key system for a vehicle, as disclosed in Patent Document 1, authentication of a portable device belongs to an LF (Low Frequency) band radio wave and a UHF (Ultra High Frequency) band. It is implemented using radio waves of a predetermined frequency.

  Specifically, LF band radio waves are used for signal transmission from the vehicle-mounted device to the portable device, and UHF band radio waves are used for signal transmission from the portable device to the on-vehicle device. The reason for using the LF band radio wave for signal transmission from the vehicle-mounted device to the portable device is to limit the reach of the radio signal to the vicinity of the vehicle. Here, the vicinity of the vehicle refers to a range that is generally within a few meters from the vehicle. The antenna directivity, transmission strength, etc. for transmitting the LF signal are adjusted so that the reach of the LF signal is an authentication area set as an area where the portable device and the vehicle-mounted device are to perform the authentication process. Has been.

  In such a setting, the in-vehicle device determines that the portable device exists in a predetermined authentication area when receiving a response signal to the LF band signal (hereinafter referred to as LF signal) transmitted by itself, and performs an authentication process. Or performing vehicle control according to the result of the authentication process. That is, the vehicle electronic key system has a function as a portable device position estimation system that determines the position of the portable device based on the presence or absence of a response to the LF signal.

JP 2012-180707 A

  According to the configuration disclosed in Patent Literature 1, even if the portable device can determine whether or not the mobile device exists in the authentication area, it cannot specify a specific position in the authentication area.

  The present disclosure has been made based on this situation, and an object thereof is to provide a portable device position estimation system capable of estimating a specific position of the portable device with respect to the vehicle. .

  The present disclosure for achieving the object includes a vehicle-mounted device (110) mounted on a vehicle and a portable device (200) associated with the vehicle-mounted device and carried by a vehicle user. In the machine position estimation system, the portable device receives a response request signal, which is a radio signal that is transmitted from the vehicle-mounted device using radio waves of a predetermined first frequency and requests the portable device to return a response signal. A portable device side receiving unit (210), a portable device side strength obtaining unit (213) for obtaining a portable device side strength that is a received signal strength of a response request signal received by the portable device side receiving unit, and a response signal, A signal including distance-related information directly or indirectly indicating the distance from the portable device to the transmission source of the signal, determined from the portable device-side strength acquired by the portable device-side strength acquisition unit, is higher than the first frequency. Transmit using radio waves of the second frequency A vehicle-side transmitter (220), and the vehicle-mounted device transmits a response request signal from a vehicle-mounted antenna (113) that is an antenna for transmitting a first-frequency radio wave mounted on the vehicle. An onboard unit side receiving unit (115) that receives a response signal via an onboard unit side transmitting unit (112), an array antenna (114) for receiving radio waves of the second frequency, and an array antenna of the response signal The direction estimation unit (F4) that estimates the direction in which the response signal has arrived based on the reception result of the mobile device and the mobile device from the vehicle-mounted antenna based on the distance-related information included in the response signal received by the vehicle-mounted device reception unit Based on the distance estimation unit (F5) that estimates the distance to the mobile device, the arrival direction of the signal from the portable device estimated by the direction estimation unit, and the distance from the vehicle-mounted antenna to the portable device estimated by the distance estimation unit Position of Position estimating section for estimating the (F6), characterized in that it comprises a.

  The distance estimation unit included in the above configuration estimates the distance from the in-vehicle antenna to the portable device by acquiring the reception intensity of the response request signal in the portable device from the portable device. In addition, the direction in which the signal from the portable device arrives, which is estimated by the direction estimation unit, corresponds to the direction in which the portable device exists when viewed from the array antenna. Therefore, the position estimation unit estimates the position of the portable device by combining the distance from the in-vehicle antenna estimated by the distance estimation unit to the portable device and the arrival direction of the signal from the portable device estimated by the direction estimation unit. Can do. According to such an aspect, the specific position of the portable device with respect to the vehicle can be estimated.

  In addition, the code | symbol in the parenthesis described in the claim shows the correspondence with the specific means as described in embodiment mentioned later as one aspect, Comprising: The technical scope of this indication is limited is not.

It is the figure which showed schematic structure of the electronic key system for vehicles concerning this embodiment. 1 is a block diagram showing a schematic configuration of an in-vehicle system 100. FIG. It is a figure for demonstrating the installation position and transmission area of LF antenna 113. FIG. 3 is a functional block diagram illustrating a schematic configuration of a vehicle side control unit 111. FIG. It is a figure which shows the relationship between the reception intensity of LF signal, and propagation distance. 4 is a block diagram showing a schematic configuration of a portable device 200. FIG. 4 is a functional block diagram illustrating a schematic configuration of a portable device side control unit 260. FIG. It is a flowchart about a movement locus | trajectory production | generation process. It is a figure for demonstrating the action | operation of the position estimation part F6. It is a flowchart about an authentication related process. It is a figure which shows an example of the movement locus | trajectory which passes 1st area Ar1. It is a figure for demonstrating the action | operation of the position estimation part F6 in a multipath environment. It is a figure which shows an example of the receiving strength for every arrival direction in a multipath environment. 3 is a functional block diagram illustrating a schematic configuration of a vehicle side control unit 111. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing an example of a schematic configuration of a vehicle electronic key system to which a portable device position estimation system according to the present invention is applied. As shown in FIG. 1, the vehicle electronic key system includes an in-vehicle system 100 mounted on a vehicle and a portable device 200 carried by a user of the vehicle. The portable device 200 is associated with the in-vehicle system 100 and has a function as a unique key for the vehicle.

  In the present embodiment, as an example, the vehicle is an engine vehicle including only an engine as a power source, but is not limited thereto. The vehicle may be a so-called hybrid vehicle including an engine and a motor as power sources, or may be an electric vehicle including only a motor as a power source.

<Outline of electronic key system for vehicles>
The in-vehicle system 100 and the portable device 200 each have a communication function for realizing a known smart entry system by performing wireless communication using radio waves in a predetermined frequency band. Specifically, the in-vehicle system 100 has a function of transmitting an LF (Low Frequency) band signal toward a predetermined range in the vehicle interior and the vicinity of the vehicle, and a function of receiving a UHF (Ultra High Frequency) band signal. The portable device 200 has a function of receiving an LF band signal transmitted from the in-vehicle system 100 and a function of transmitting a UHF band signal. Here, the LF band indicates 30 kHz to 300 kHz, and the UHF band indicates 300 MHz to 3 GHz.

  The frequency of the LF band used for signal transmission from the in-vehicle system 100 to the portable device 200 in the vehicle electronic key system is, for example, 125 kHz or 134 kHz. The UHF band frequency used for signal transmission from the portable device 200 to the in-vehicle system 100 is, for example, 315 MHz, 920 MHz, or the like.

  Here, as an example, 134 kHz is used as a frequency used for signal transmission from the in-vehicle system 100 to the portable device 200, and as a frequency used for signal transmission from the portable device 200 to the in-vehicle system 100, Taking the case of 315 MHz as an example, the configuration of each unit will be described. The frequency used for signal transmission from the in-vehicle system 100 to the portable device 200 corresponds to the first frequency recited in the claims, and the frequency used for signal transmission from the portable device 200 to the in-vehicle system 100 is claimed. This corresponds to the second frequency described in.

  The first frequency only needs to be set to a frequency of 1 MHz or less, and does not need to belong to the LF band. In addition, from the viewpoint of ease of forming a transmission area, which will be described later, it is preferable that the first frequency is set to a frequency belonging to a frequency band from 20 kHz to 200 kHz. The second frequency may be set to a frequency other than those described above. For example, the second frequency may be a frequency used in short-range wireless communication. The short-range wireless communication here is wireless communication based on a predetermined short-range wireless communication standard in which the communication range is, for example, about several tens of meters at the maximum. As the short-range wireless communication standard, for example, Bluetooth Low Energy (Bluetooth is a registered trademark), Wi-Fi (registered trademark), ZigBee (registered trademark), or the like can be adopted. The frequency used in short-range wireless communication is, for example, a band from 2400 MHz to 2480 MHz (hereinafter, 2.4 GHz band).

  The in-vehicle system 100 is configured so that a range within a few meters from the vehicle is a vehicle communication area. The vehicle communication area here is a range in which an LF band signal (hereinafter referred to as an LF signal) transmitted by the in-vehicle system 100 propagates while maintaining a predetermined signal strength. The size of the vehicle communication area may be designed as appropriate.

  In such a configuration, the in-vehicle system 100 periodically transmits an LF signal as a polling signal, and performs authentication processing by wireless communication with the portable device 200 based on the response from the portable device 200 to the polling signal. carry out. The polling signal is an LF signal that requests the portable device 200 to return a predetermined response signal. Note that, as described above, radio waves in the UHF band (more specifically, at the second frequency) are used for the response from the portable device 200 to the in-vehicle system 100. That is, the response signal returned by the portable device 200 is a UHF band radio signal.

  Authentication of the portable device 200 by the in-vehicle system 100 is realized by a well-known challenge-response method. The challenge-response method is a method of performing authentication by transmitting and receiving a challenge code and a response code between an authenticating device (hereinafter, an authenticating device) and an authenticating device (hereinafter, an authenticated device). is there. Here, the in-vehicle system 100 corresponds to an authentication-side device, and the portable device 200 corresponds to an authenticated-side device.

  Note that each of the portable device 200 and the in-vehicle system 100 stores a common encryption key used for authentication processing. Further, a unique identification number (hereinafter, portable device ID) is assigned to the portable device 200, and the portable device ID is registered in the in-vehicle system 100. The portable device ID may be used as the encryption key described above. Note that authentication processing by wireless communication between the in-vehicle system 100 and the portable device 200 may also be referred to as code verification in this technical field.

  The in-vehicle system 100 executes predetermined vehicle control such as door locking / unlocking or engine starting based on the successful authentication of the portable device 200. That is, a well-known smart entry function is provided. Hereinafter, specific configurations and operations of the in-vehicle system 100 and the portable device 200 will be described.

<About the configuration of the in-vehicle system 100>
First, the configuration of the in-vehicle system 100 will be described. The in-vehicle system 100 includes an authentication ECU 110, a touch sensor 120, a start button 130, a lock button 140, a body ECU 150, and an engine ECU 160 as shown in FIG. The authentication ECU 110 is connected to the touch sensor 120, the start button 130, the lock button 140, the body ECU 150, and the engine ECU 160 through a LAN (Local Area Network) built in the vehicle so as to be able to communicate with each other. Yes.

  The authentication ECU 110 is an ECU (ECU: Electronic Control Unit) that performs a process of authenticating the portable device 200 by wireless communication (that is, an authentication process). This authentication ECU 110 includes a vehicle-side control unit 111, an LF transmission unit 112, an LF antenna 113, an array antenna 114, and a UHF reception unit 115 as finer constituent elements. The authentication ECU 110 corresponds to the vehicle-mounted device described in the claims.

  The vehicle-side control unit 111 is configured as a normal computer including a CPU 1111, a RAM 1112, a ROM 1113, an I / O 1114, and a bus line that connects these configurations. The ROM 1113 stores a program (hereinafter referred to as a vehicle program) for causing a normal computer to function as the vehicle-side control unit 111. The above-described smart entry function and the like are realized by the CPU 1111 executing the vehicle program. Details of the vehicle-side control unit 111 will be described later. The vehicle-side control unit 111 generally generates data to be transmitted to the portable device 200 and outputs the data to the LF transmission unit 112 and the UHF reception unit 115, and acquires data received by the UHF reception unit 115.

  The LF transmission unit 112 converts the data input from the vehicle-side control unit 111 into a carrier wave signal by performing predetermined processing such as encoding, modulation, and digital / analog conversion. Then, the carrier wave signal is output to the LF antenna 113 and radiated as a radio wave. The LF transmission unit 112 corresponds to the transmission unit described in the claims. The LF transmitter 112 corresponds to the vehicle-mounted device-side transmitter described in the claims.

  The LF antenna 113 is an antenna that converts the carrier wave signal input from the LF transmitter 112 into an LF band radio wave and radiates it to space. One or a plurality of LF antennas 113 are provided so as to form a desired transmission area for the vehicle. The LF antenna 113 corresponds to the vehicle-mounted antenna described in the claims. The transmission area of the LF antenna 113 is an area that reaches the signal transmitted from the LF antenna 113 while maintaining a signal level at which the portable device 200 can receive (in other words, can be decoded). The vehicle communication area for the vehicle itself corresponds to an area formed by combining transmission areas formed by the LF antennas 113.

  2 discloses a configuration in which the LF antenna 113 is disposed inside the block showing the authentication ECU 110. However, the LF antenna 113 is actually disposed outside the housing of the authentication ECU 110, for example, near the door handle of the vehicle. ing. In this embodiment, as an example, the vehicle is provided with a driver's seat side antenna 113a, a passenger seat side antenna 113b, and a vehicle interior antenna 113c as the LF antenna 113 as shown in FIG.

  The driver seat side antenna 113a is the LF antenna 113 provided near the handle of the driver seat door (including the inside of the handle). The driver's seat side antenna 113a is designed such that an area within 5 m from the driver's seat door outside the passenger compartment is a transmission area. The size of the transmission area of the LF antenna 113 may be adjusted by adjusting the transmission power of the signal transmitted from the LF antenna 113. That is, the transmission power of the signal at the driver's seat side antenna 113a is set so that the LF signal transmitted from the driver's seat side antenna 113a does not propagate for more than 5 m. Za in the figure conceptually represents the transmission area of the driver's seat side antenna 113a. In the present embodiment, the driver's seat of the vehicle is provided on the right side of the front seat.

  The passenger seat side antenna 113b is an LF antenna 113 provided near the handle of the passenger seat door. The passenger seat side antenna 113b is designed such that an area within 5 m from the passenger seat door is a transmission area outside the passenger compartment. Zb in FIG. 3 conceptually represents the transmission area of the passenger side antenna 113b. Note that the upper limit of the propagation distance of the LF signal from the LF antenna that forms the transmission area outside the passenger compartment, such as the driver's seat side antenna 113a and the passenger seat side antenna 113b, is not limited to 5 m. The transmission power may be set such that the propagation distance of the LF signal is 3 m, 5 m, 10 m, or the like.

  The vehicle interior antenna 113c is an LF antenna having the entire vehicle interior as a transmission area. Although only one vehicle interior antenna 113c is shown here, a plurality of vehicle interior antennas 113c may be provided. In FIG. 3, the transmission area of the vehicle interior antenna 113c is not shown.

  The installation position of each LF antenna 113 in the vehicle may be expressed as a point on a two-dimensional coordinate centering on an arbitrary position of the vehicle and parallel to the vehicle horizontal plane. Here, the vehicle horizontal plane is a plane orthogonal to the height direction of the vehicle. The X axis forming the two-dimensional coordinate system may be parallel to the vehicle front-rear direction and the Y axis may be parallel to the vehicle width direction. The center of the two-dimensional coordinate system may be, for example, the center of the rear wheel axle. Data indicating the installation position of the LF antenna 113 is stored in the ROM 1113.

  In addition, the installation position and transmission area of the LF antenna 113 mounted on a vehicle are not restricted to the aspect mentioned above. The installation position and the like of the LF antenna 113 may be appropriately designed so as to form a desired vehicle communication area as a whole. In addition to the LF described above, the vehicle may be provided with an LF antenna 113 having a transmission area in the trunk and an LF antenna 113 having a transmission area in the vicinity of the trunk door.

  In the present embodiment, as an example, a range in which a signal transmitted from the LF antenna 113 reaches a signal level that can be decoded by the portable device 200 is used as a transmission area of the LF antenna 113. Not limited to this. As another aspect, the transmission area may be a range that propagates at a signal level at which the received signal strength at the portable device 200 is equal to or greater than a predetermined area determination threshold. The area determination threshold value used here is a value appropriately designed by the designer among values larger than the lower limit value (that is, the decoding limit value) of the decodable signal level. In such an aspect, even when the portable device 200 receives a signal from the in-vehicle system 100 with a received signal strength that can be decoded, when the received signal strength is equal to or less than the area determination threshold value. It is determined that it exists outside the transmission area, and no response is returned. The transmission power of the signal at the LF antenna 113 may be set to a level that does not return a response signal when the portable device 200 is at least 10 m away from the LF antenna 113.

  The LF antenna 113 can be realized as a magnetic field antenna using a bar antenna, for example. The magnetic field type antenna here is an antenna that generates a current by changing a magnetic field, and is an antenna that has a stronger magnetic field component than an electric field component in the vicinity of the radiating element. The vicinity here is a range called a so-called near field and corresponds to a range in which the distance from the radiating element is within λ / 2π. Note that λ is the wavelength of the radio wave to be transmitted / received.

  In the near field, the magnetic field radiated by the magnetic field type antenna tends to attenuate in inverse proportion to the third power of the distance and the electric field tends to attenuate in inverse proportion to the second power of the distance. Since the LF antenna 113 is an antenna for transmitting a radio wave of 134 kHz, the near field for the LF antenna 113 is a range within 356 m from the antenna. That is, the range of several meters to several tens of meters from the vehicle is an extremely close region for the LF antenna 113 that transmits 134 kHz. Therefore, the intensity of the signal transmitted by the LF antenna 113 is sharply attenuated with the cube of the distance. The LF antenna 113 of the present embodiment realizes a desired transmission area (and thus a vehicle communication area) using the properties of the magnetic field antenna.

  The array antenna 114 is an array antenna including a plurality of UHF antennas 114a, 114b, and 114c. Hereinafter, when the three UHF antennas 114a, 114b, and 114c are not distinguished, they are referred to as UHF antennas 114x. The UHF antenna 114x is an antenna for receiving radio waves in the UHF band. When the UHF antenna 114x receives a radio wave in the UHF band, the UHF antenna 114x converts it into an electrical signal and provides it to the UHF receiver 115.

  The array antenna 114 has a known configuration, and the three UHF antennas 114a, 114b, and 114c are arranged at intervals determined based on the wavelength of radio waves to be transmitted and received. Specifically, the three UHF antennas 114a, 114b, and 114c are arranged at equiangular intervals on a circumference of a radius determined based on the wavelength of a radio wave to be transmitted and received. The array antenna 114 is preferably arranged at a position where the outside of the passenger compartment can be seen through the window of the vehicle, such as a ceiling portion in the passenger compartment. The position where the outside of the passenger compartment can be seen can be said to be a position where the radio wave transmitted by the portable device 200 existing near the door outside the passenger compartment can be directly received. Data indicating the installation position of the array antenna 114 may be stored in the ROM 1113. The data indicating the installation position of the array antenna 114 includes data indicating the installation position of each UHF antenna 114x. Data indicating the installation position of the array antenna 114 or the LF antenna 113 is referred to as antenna position data for convenience.

  The UHF receiver 115 extracts data included in the received signal by performing predetermined processing such as analog-digital conversion, demodulation, and decoding on the signal input from each UHF antenna 114x. Then, the extracted data is provided to the vehicle side control unit 111. The UHF receiver 115 corresponds to the vehicle-mounted device-side receiver described in the claims.

  The touch sensor 120 is mounted on each door handle of the vehicle and detects that the user is touching the door handle. The detection result of each touch sensor 120 is sequentially output to the authentication ECU 110. The start button 130 is a push switch for the user to start the engine. When a push operation is performed by the user, the start button 130 outputs a control signal indicating that to the vehicle-side control unit 111.

  The locking button 140 is a button for the user to lock the door of the vehicle. The locking button 140 may be provided on each door handle of the vehicle. When the lock button 140 is pressed by the user, it outputs a control signal indicating that to the authentication ECU 110.

  The body ECU 150 is an ECU that controls various actuators mounted on the vehicle. For example, the body ECU 150 outputs a drive signal for controlling the locking / unlocking of the door provided on the vehicle to the door lock motor provided on each vehicle door based on an instruction from the authentication ECU 110, and opens / closes each door. Do the lock. The body ECU 150 acquires information indicating the open / closed state of each door provided in the vehicle, the locked / unlocked state of each door, and the like. The door open / close state may be detected by a courtesy switch.

  Engine ECU 160 is an ECU that controls the operation of the engine. For example, when engine ECU 160 obtains a start instruction signal instructing engine start from authentication ECU 110, engine ECU 160 starts the engine. In addition, the authentication ECU 110 is connected to various ECUs and sensors (not shown), and is configured to be able to acquire various information indicating the state of the vehicle such as a shift position.

<About the function of the vehicle side control part 111>
As shown in FIG. 4, the vehicle-side control unit 111 includes a vehicle information acquisition unit F <b> 1, a vehicle state determination unit F <b> 2, an approach detection unit F <b> 3, direction estimation, as functional blocks realized by the CPU executing the above-described vehicle program. A unit F4, a distance estimation unit F5, a position estimation unit F6, an authentication processing unit F7, and a vehicle control unit F8 are provided. Moreover, the vehicle side control part 111 is provided with the map memory | storage part M1 implement | achieved using non-volatile storage media, such as ROM. Note that some or all of the functions of the vehicle-side control unit 111 may be realized as hardware using one or a plurality of IC chips.

  The vehicle information acquisition unit F1 acquires various information (that is, vehicle information) indicating the state of the vehicle from a sensor or ECU mounted on the vehicle such as the touch sensor 120. Vehicle information includes, for example, whether the user touches the door handle, whether the door is open, whether the brake pedal is depressed, whether the start button 130 is pressed, whether each door is locked, Applicable to engine operating conditions.

  Whether or not the user touches the door handle can be acquired from the touch sensor 120, and whether or not the start button 130 is pressed can be determined from a signal output from the start button 130. The open / closed state of the door and the locked / unlocked state of each door can be acquired from the body ECU 150, for example. The door open / close state may be detected by a courtesy switch. Whether or not the brake pedal is depressed may be detected by a brake pedal sensor that detects the position (substantially an angle) of the brake pedal. In addition, the information contained in vehicle information is not restricted to what was mentioned above. The vehicle information includes a shift position detected by a shift position sensor (not shown), an operating state of a parking brake, and the like.

  The vehicle state determination unit F2 determines the state of the vehicle based on the vehicle information acquired by the vehicle information acquisition unit F1. The vehicle state determination unit F2 includes a parking determination unit F21 as a finer functional block. The parking determination unit F21 determines whether or not the vehicle is parked based on the vehicle information acquired by the vehicle information acquisition unit F1. For example, the parking determination unit F21 determines that the vehicle is parked when the engine is off, the shift position is set to the parking position, and all the doors are locked. Of course, a known algorithm for determining whether or not the vehicle is parked can be employed.

  The approach detection unit F3 is configured to detect that the portable device 200 has entered the vehicle communication area. When it is determined that the vehicle is parked by the parking determination unit F21, the approach detection unit F3 cooperates with the LF transmission unit 112 to send a polling signal to each LF antenna 113 at a predetermined cycle (for example, 200 milliseconds). Send from. This polling signal is a signal that requests a response from the portable device 200. By receiving a response signal to the polling signal, the approach detection unit F3 can detect that a communication terminal that may be the portable device 200 exists in the vehicle communication area. The distance from the vehicle to the farthest end of the vehicle communication area corresponds to the estimated execution distance described in the claims.

  The direction estimation unit F4, the distance estimation unit F5, and the position estimation unit F6 are configurations for estimating the position of the portable device 200 (hereinafter, portable device position). For convenience, the process performed by the vehicle-side control unit 111 to estimate the position of the portable device 200 is referred to as a position estimation process. The vehicle-side control unit 111 performs position estimation processing in cooperation with the LF transmission unit 112 and the UHF reception unit 115. Details of the position estimation process, in other words, details of the functions of the direction estimation unit F4, the distance estimation unit F5, and the position estimation unit F6 will be described later.

  The vehicle-side control unit 111 transmits a predetermined position estimation signal to the portable device 200 in cooperation with the LF transmission unit 112 in the course of the position estimation process. The position estimation signal is a signal requesting to return a signal indicating the reception intensity of the position estimation signal. The signal for position determination may be a signal provided only for estimating the position of the portable device, or uses a signal for achieving another purpose such as a polling signal or a challenge signal accompanying the authentication process. May be. In other words, various LF signals such as a polling signal and a challenge signal may be used as the position estimation signal.

  The authentication processing unit F7 is configured to perform authentication processing in cooperation with the LF transmission unit 112 and the UHF reception unit 115. The authentication processing unit F7 generates a challenge code in the course of the authentication processing, and causes the LF transmission unit 112 to transmit an LF signal (hereinafter, challenge signal) including the challenge code. The challenge code may be a random number generated using, for example, a random number table. The challenge signal is a signal for requesting the portable device 200 to return a code (hereinafter referred to as a response code) obtained by encrypting the transmitted challenge code using an encryption key registered in the main body of the portable device 200 in advance. It is.

  Further, as a more preferable aspect, the authentication processing unit F7 of the present embodiment, as a result of the authentication processing, when the authentication of the portable device 200 is successful, an LF signal indicating that the authentication processing is successful for the portable device 200 (Hereinafter, an authentication success notification signal) is transmitted. Details of the portable device position estimation process and the authentication process will be described later.

  The vehicle control unit F8 is configured to perform vehicle control according to the position of the portable device estimated by the position estimation unit F6, the state of the vehicle, and the user operation when the authentication processing by the authentication processing unit F7 is successful. For example, when the vehicle control unit F8 has succeeded in the authentication process in a state where the door of the vehicle is locked and the position estimation unit F6 determines that the portable device 200 exists around the vehicle outside the passenger compartment, Then, the door lock mechanism of the vehicle is set to the unlocking preparation state. The unlocking preparation state is a state in which the user can unlock the door only by touching the touch sensor 120 of the door. When a signal indicating that the user is touching is input from the touch sensor 120, the door lock is unlocked in cooperation with the body ECU 150. Further, the vehicle control unit F8, for example, when the start button 130 is pressed by the user when the engine is stopped and the position estimation unit F6 determines that the portable device 200 exists in the vehicle interior. Starts the engine in cooperation with the engine ECU 160. In addition, the contents of the vehicle control performed by the vehicle control unit F8 may be appropriately designed in accordance with the execution conditions of the authentication process described later.

  The map storage unit M1 is a storage device that stores an LF_RSSI map. The LF_RSSI map is data indicating a correspondence relationship between the distance between the LF antenna 113 and the portable device 200 and the signal strength (RSSI: Received Signal Strength Indication) of the LF signal received by the portable device 200. Generally, since a radio signal attenuates as it propagates through space, the RSSI of the LF signal in the portable device 200 decreases as the distance between the vehicle and the portable device 200 increases. In particular, in the present embodiment, since the transmission area is formed using the characteristics in the near field of the LF antenna 113, the RSSI of the LF signal attenuates steeply in inverse proportion to the cube of the distance. The LF_RSSI map is data indicating the correspondence between the distance between terminals and the RSSI of the LF signal in the portable device 200 as shown in FIG. The LF_RSSI map may be created based on actual tests, simulations, and the like. The horizontal axis of the graph shown in FIG. 5 represents the distance from the LF antenna to the portable device 200, and the vertical axis represents LF_RSSI.

<About the configuration of the portable device 200>
Next, the configuration of the portable device 200 will be described. As shown in FIG. 6, the portable device 200 includes an LF communication module 210, a UHF communication module 220, a vibrator 230, a movement sensor 240, a battery 250, and a portable device-side control unit 260. The portable device side control unit 260 and each of the LF communication module 210, the UHF communication module 220, the vibrator 230, and the movement sensor 240 are communicably connected. The battery 250 is electrically connected to the portable device side control unit 260.

  The LF communication module 210 has a configuration for receiving an LF signal transmitted from the in-vehicle system 100. The LF communication module 210 is realized using the LF antenna 211 and the LF receiving unit 212. The LF communication module 210 corresponds to the mobile device side receiving unit described in the claims. The LF antenna 211 is an antenna for receiving LF band radio waves. The LF antenna 211 is connected to the LF receiving unit 212, converts the received radio wave into an electric signal, and outputs the electric signal to the LF receiving unit 212.

  The LF reception unit 212 performs predetermined processing such as analog-digital conversion, demodulation, and decoding on the electric signal input from the LF antenna 211. The LF reception unit 212 extracts data included in the reception signal and provides the data to the portable device side control unit 260. The LF reception unit 212 is realized by using, for example, an integrated circuit (that is, an IC) that performs part or all of the above processing.

  The LF reception unit 212 includes an RSSI circuit 213 that detects a received signal strength (RSSI) that is the strength of a signal received by the LF antenna 211. The RSSI circuit 213 may be realized using a known circuit configuration. The RSSI detected by the RSSI circuit 213 is provided to the portable device control unit 260. The RSSI detected by the RSSI circuit 213 is the RSSI of the LF signal. Therefore, hereinafter, the RSSI detected by the RSSI circuit 213 is also referred to as LF_RSSI for convenience.

  The RSSI circuit 213 may be provided outside the LF receiving unit 212. The RSSI circuit 213 corresponds to the portable device-side strength acquisition unit described in the claims. Further, an analog circuit or the like that substitutes for some of the functions of the LF receiving unit 212, such as an amplifier or a demodulation circuit, may be provided between the LF antenna 211 and the LF receiving unit 212.

  The UHF communication module 220 is configured to allow the portable device 200 to communicate with the in-vehicle system 100 using UHF radio waves. The UHF communication module 220 corresponds to the portable device-side transmitter described in the claims. The UHF communication module 220 is realized using the UHF antenna 221 and the UHF transmission unit 222.

  The UHF antenna 221 is an antenna for transmitting UHF band radio waves. The UHF antenna 221 is connected to the UHF transmission unit 222 and converts the electric signal input from the UHF transmission unit 222 into a radio wave and radiates it. The UHF transmission unit 222 converts the baseband signal into a carrier wave signal by performing predetermined processing such as encoding, modulation, and digital / analog conversion on the baseband signal input from the portable device-side control unit 260. Then, the generated carrier wave signal is output to the UHF antenna 221 and radiated as a UHF band radio wave. The UHF transmission unit 222 is realized by using, for example, an integrated circuit (that is, an IC) that performs part or all of the above processing.

  The UHF communication module 220 is configured such that a transmission signal from the UHF antenna 221 propagates at least 10 m or more. The operation state of the UHF transmission unit 222 is controlled by the portable device side control unit 260. Controlling the operation state of the UHF transmission unit 222 corresponds to controlling the power supply state to the UHF transmission unit 222. Note that an analog circuit, an amplifier, a noise filter circuit, or the like that replaces part of the functions of the UHF transmission unit 222 may be provided between the UHF antenna 221 and the UHF transmission unit 222.

  Vibrator 230 is a device that generates vibration based on an instruction from portable device side control unit 260. The vibrator 230 can be realized by a motor with an eccentric weight, for example. In addition, you may implement | achieve using the magnetic circuit of a piezoelectric element or a speaker instead of a motor.

  Vibrator 230 plays a role as a notification device for notifying the user of various information such as the execution state of the authentication process with the vehicle and the remaining power of battery 250 by vibration. That is, the vibrator 230 operates based on an instruction from the portable device-side control unit 260 and generates a predetermined pattern of vibrations. The elements constituting the vibration pattern include vibration intensity and vibration rhythm. The vibration rhythm includes the vibration generation interval and duration.

  In the present embodiment, as an example, vibrator 230 is employed as a notification device, but the present invention is not limited thereto. As the notification device, a display, a speaker, or a vibrator can be used. The speaker also includes a buzzer. A plurality of types of devices may be provided as a notification device.

  The movement sensor 240 is a sensor for detecting that the portable device 200 is moving. In addition, the case where the portable device 200 moves is a case where a user carrying the portable device 200 is moving (for example, walking). When the user is walking, the mobile device 200 is subjected to acceleration derived from the user's walking. The movement sensor 240 may be realized using a known acceleration sensor, for example. As the acceleration sensor as the movement sensor 240, for example, a three-axis acceleration sensor that detects accelerations in three axial directions orthogonal to each other can be employed. Of course, the acceleration sensor as the movement sensor 240 may be a biaxial acceleration sensor or a uniaxial acceleration sensor. The output signal of the movement sensor 240 is sequentially input to the portable device side control unit 260.

  The movement sensor 240 may be a gyro sensor or a geomagnetic sensor. What is necessary is just to detect the change of the physical state quantity which arises with a user's movement. The movement sensor 240 may be a switch element configured such that the contact state of the movable contact with the fixed contact changes (in other words, vibrates) due to relatively weak vibration such as walking of the user. When the user is walking with the portable device 200, such a switch element outputs a pulse-like signal because the terminal repeatedly touches and leaves. On the other hand, when the portable device 200 is placed on a stable place such as a desk or a shelf, the contact state between the terminals is stable in either contact or non-contact, so the pulse signal is Not output. That is, the above switch element can also be used as the movement sensor 240. The battery 250 is electrically connected to the portable device side control unit 260, and supplies power to each unit (for example, the UHF transmission unit 222) included in the portable device 200 under the control of the portable device side control unit 260. .

  The portable device side control unit 260 is configured mainly with a computer. That is, the portable device side control unit 260 is realized by using a CPU, RAM, ROM, I / O, clock oscillator, etc. (not shown). The ROM stores a program for causing a normal computer to function as the portable device-side control unit 260 (hereinafter referred to as a portable device program). The portable device side control unit 260 realizes a smart entry system or the like when the CPU executes a portable device program stored in the ROM. In addition to the above program, the ROM stores an encryption key used to generate a response code from the challenge code. Detailed functions of the portable device control unit 260 will be described next.

<About the function of the portable device control unit 260>
As shown in FIG. 7, the portable device-side control unit 260 is a function block realized by executing the above-described portable device program, as illustrated in FIG. 7, the received data acquisition unit G1, the LF_RSSI acquisition unit G2, the response processing unit G3, and the notification. A processing unit G4 is provided. Note that some or all of the functional blocks included in the portable device-side controller 260 may be realized as hardware using one or a plurality of IC chips.

  The reception data acquisition unit G1 acquires data received by the LF communication module 210. For example, when the LF communication module 210 receives a challenge signal, the received data acquisition unit G1 acquires a challenge code included in the received challenge signal. In addition, the LF_RSSI acquisition unit G2 is configured to sequentially acquire the LF_RSSI detected by the RSSI circuit 213 from the in-vehicle system 100 indicating that the authentication process has been successful. The RSSI acquired by the LF_RSSI acquisition unit G2 is held in the RAM for a certain period of time.

  The response processing unit G3 is configured to generate a response signal for the LF signal transmitted from the in-vehicle system 100 and to perform a process of returning to the in-vehicle system 100 in cooperation with the UHF communication module 220. For example, when the LF reception unit 212 receives a position estimation signal, the response processing unit G3 generates a response signal including LF_RSSI detected by the RSSI circuit 213 with respect to the position estimation signal. The generated response signal is output to the UHF transmission unit 222 and returned to the in-vehicle system 100. With this configuration, when receiving the position estimation signal, the portable device 200 returns a response signal indicating the RSSI of the received position estimation signal to the in-vehicle system 100 at a predetermined output level. When a challenge signal is received, a response code obtained by encrypting the challenge code included in the signal using a pre-registered encryption key is generated, and a response signal indicating the response code (a so-called response signal) Is transmitted to the UHF transmitter 222.

  The notification processing unit G4 is configured to notify the user of predetermined information by operating the vibrator 230 in a mode (in other words, a vibration pattern) according to the execution status of the authentication process. For example, when the LF receiving unit 212 receives a challenge signal, the portable device-side control unit 260 performs vibration for a relatively short time (for example, 0.5 seconds) at a predetermined interval (for example, 1 second) a predetermined number of times. (For example, twice). Further, when it is detected that the authentication process is successful based on the fact that the LF reception unit 212 has received the authentication success notification signal, the LF reception unit 212 continuously vibrates for a predetermined time (for example, 1.5 seconds). According to such an aspect, the user can recognize the execution status of the authentication process based on the vibration pattern.

  In addition, when the portable device 200 includes a display as a notification device, the notification processing unit G4 may notify the user of predetermined information by displaying a predetermined icon image or text on the display. When a speaker is provided as the notification device, predetermined information may be notified to the user by outputting an alarm sound or a voice message from the speaker. The user may be notified of predetermined information by causing an indicator such as an LED to emit light in a predetermined light emission pattern.

<Movement path generation process>
Next, the movement locus generation process performed by the vehicle-side control unit 111 will be described using the flowchart shown in FIG. The movement locus generation process is a process for generating data indicating the movement locus of the portable device 200. The movement trajectory generation process includes a plurality of position estimation processes. This movement locus generation process may be started when a response signal to a polling signal that is periodically transmitted in a state where the vehicle is parked is received. That is, the trigger is started when the approach detection unit F3 detects the approach of the portable device 200.

  Note that the timing at which the approach detection unit F3 transmits the polling signal in the plurality of LF antennas 113 is different for each antenna. That is, polling signals are transmitted from the plurality of LF antennas 113 at different timings. Here, as an example, it is assumed that the polling signal is transmitted at a predetermined time difference in the order of the driver's seat side antenna 113a, the passenger seat side antenna 113b, and the vehicle interior antenna 113c. The time difference here is set to a time longer than a response waiting time described later.

  According to such an aspect, the position estimation unit F6 can narrow down which transmission area of the LF antenna 113 the portable device 200 exists based on the timing at which the response signal for the position specifying signal is received. . That is, the LF antenna 113 that has transmitted the polling signal to which the portable device 200 responds can be uniquely identified. For example, when the response signal is received within the response waiting time from the time when the polling signal is transmitted from the driver seat side antenna 113a, the portable device 200 determines that the mobile device 200 exists within the transmission area of the driver seat side antenna 113a.

  Note that the method of narrowing down the area where the portable device 200 exists, in other words, the transmission source of the LF signal to which the portable device 200 responds is not limited to the method described above. In addition to the methods described above, various known methods can be applied. For example, an antenna code unique to each LF antenna 113 is set, and the response request signal transmitted from each LF antenna 113 includes an antenna code corresponding to the LF antenna. Then, the portable device 200 is configured to return a response signal including an antenna code included in the received response request signal.

  Even with such a configuration, the position estimation unit F6 specifies which LF antenna 113 the mobile device 200 has responded to based on the antenna code included in the response signal. can do. As a result, the area where the portable device 200 exists can be specified. Hereinafter, for convenience, the LF antenna 113 that has transmitted the polling signal from which the portable device 200 has returned the response signal is referred to as a transmission source antenna.

  First, in step S101, the position estimation unit F6 initializes the number k of transmission executions, which is a parameter used in the subsequent processing (specifically, sets k = 1), and proceeds to step S102. The transmission execution count k is a variable in which a natural number is set.

  In step S102, the position estimation unit F6 outputs a position estimation signal to the LF transmission unit 112, transmits the position estimation signal from the LF antenna 113 serving as a transmission source antenna, and proceeds to step S103. In step S103, it is determined in cooperation with the UHF receiver 115 whether or not a response signal to the position estimation signal has been received. If a response signal to the position estimation signal is received, an affirmative decision is made in step S103 and step S104 is executed. On the other hand, if the response signal cannot be received even after a predetermined response waiting time has elapsed since the transmission of the position estimation signal, a negative determination is made in step S103 and step S107 is executed.

  In step S104, the direction estimation unit F4 estimates the arrival direction of the response signal based on the reception result of the array antenna 114. Various known methods can be used for direction-of-arrival estimation by the array antenna 114. For example, MUSIC (Multiple Signal Classification) method, ESPRIT (Estimation of Signal Parameters via Rotational Invariance Techniques) method, etc. can be used. In addition, when the array antenna 114 is an adaptive array antenna, a beamformer or the like can be used. Of course, in addition to the above, the direction of arrival is estimated based on the positional relationship of each UHF antenna 114x, the intensity of the radio wave received by each UHF antenna 114x, and the phase difference (or reception time difference) of the signals received by each UHF antenna 114x. Any known method can be employed.

  The direction estimation unit F4 acquires, as the arrival direction, a direction in which the reception intensity is equal to or greater than a predetermined threshold as a result of the arrival direction estimation processing, and indicates the reception intensity for each arrival direction (hereinafter, direction-intensity data). ) Is generated. The generated direction-intensity data is stored in the RAM 1112 in association with time information indicating the detection time.

  This direction-intensity data is referred to by the position estimation unit F6, and the direction of the portable device is specified. The array antenna 114 is transmitted from the portable device 200 in addition to the radio wave that has arrived without being reflected by another object (in other words, directly) after being transmitted from the portable device 200 (hereinafter referred to as a direct wave). A radio wave (hereinafter referred to as a reflected wave) in which the received radio wave is reflected by another object can also be received. When the array antenna 114 receives a direct wave, the array antenna 114 detects the direction in which the direct wave arrives as the arrival direction. When the array antenna 114 receives a reflected wave having an intensity equal to or greater than a predetermined threshold, the direction in which the reflected wave arrives may be detected as the arrival direction.

  In other words, as a result of the direction of arrival estimation processing, information on the direction in which the direct wave arrives (direct wave direction) and the direction in which the reflected wave arrives (referred to as reflected wave direction) are mixed. There may be. The direct wave direction corresponds to the direction in which the portable device 200 exists (hereinafter, the portable device direction). When a plurality of candidates are detected as the arrival directions, the position estimation unit F6 of the present embodiment employs the direction with the highest received intensity as the direct wave direction. However, as will be described later separately as a modified example, when the position of the portable device determined from the direction in which the reception strength is the maximum is greatly deviated from the movement locus of the portable device 200 so far, the reception strength is the second highest. The arrival direction may be regarded as the mobile device direction. The direction estimation unit F4 may perform the process of determining the direction of the mobile device from the plurality of arrival directions.

  When the process in step S104 is completed, step S105 is executed. In step S105, the distance estimation unit F5 uses the LF antenna 113 serving as the transmission source antenna from the portable device based on the LF_RSSI included in the response signal from the portable device 200 and the LF_RSSI map stored in the map storage unit M1. A distance D up to 200 is estimated. Specifically, in the LF_RSSI map, the distance associated with the LF_RSSI included in the received response signal is adopted as the distance D from the transmission source antenna to the portable device 200 in step S105. When the process in step S105 is completed, the process proceeds to step S106.

  In step S106, the position estimation unit F6, based on the portable device direction determined based on the estimation result of the direction estimation unit F4 in step S104, and the distance D from the transmission source antenna estimated by the distance estimation unit F5 in step S105, Calculate the mobile device position. As shown in FIG. 9, the position of the portable device is an intersection Px between the line L1 indicating the direction of the portable device specified in step S104 and the line L2 indicating the distance D from the transmission source antenna specified in step S105. In addition, in FIG. 9, the case where a transmission source antenna is the driver's seat side antenna 113a is illustrated as an example.

  The portable device position calculated by the position estimation unit F6 may be represented as a point on a two-dimensional coordinate system with a predetermined point on the vehicle as the origin, similarly to the installation positions of various antennas. Data indicating the position of the portable device is stored in the RAM in association with the calculation time, the number of transmission executions k serving as a calculation number, and the like. When the process in step S106 is completed, step S108 is executed. Note that a series of processing from step S102 to step S106 corresponds to one position estimation processing.

  In step S107, data indicating that the position estimation of the portable device 200 has failed (hereinafter, error information) is stored in the RAM 1112 in association with the transmission execution count k. For example, the error information may be a code indicating that the position is unknown. When the process in step S107 is completed, step S108 is executed. In the present embodiment, as an example, the position estimation process is continued even when a response signal to the position estimation signal is not obtained. However, the present invention is not limited to this. If a response signal to the position estimation signal is not obtained, this flow may be terminated and the polling signal may be transmitted again.

  In step S108, the position estimation unit F6 increases the value of the transmission execution count k by 1 (that is, increments), and proceeds to step S109. In step S109, the position estimation unit F6 determines whether or not the transmission execution count k exceeds a preset maximum estimation count N. If the transmission execution count k is less than or equal to the maximum estimated count N, a negative determination is made in step S109 and the processing from step S101 is executed again. If the transmission execution count k exceeds the maximum estimated count N, an affirmative decision is made in step S109 and the flow is terminated. The maximum estimated number N may be designed as appropriate, and may be set to 10 or 20, for example.

  It should be noted that the interval for transmitting the position estimation signal in step S102 is adjusted to be a predetermined position confirmation interval using a timer or the like. The specific value of the position confirmation interval may be designed as appropriate. Here, as an example, the position confirmation interval is 300 milliseconds. Of course, as another mode, the position confirmation interval may be 100 milliseconds or 200 milliseconds. Further, the position confirmation interval may be 1 second or the like. The position confirmation interval may be designed according to the average walking speed of a person.

  As the position confirmation interval is shortened, the vehicle frequently confirms the position of the portable device, so that the user's trajectory can be detected densely. On the other hand, if the position confirmation interval is set to a relatively long value, the frequency of transmitting the LF signal can be reduced, so that the power consumption in both the in-vehicle system 100 and the portable device 200 can be reduced.

  Further, by introducing the maximum estimated number N, the user's position from when the user enters the vehicle communication area until boarding is sampled a plurality of times. That is, it is possible to generate data indicating a movement trajectory until the user approaches from the far side of the vehicle and gets on the vehicle in the parked state.

  Data indicating the position of the portable device at a plurality of points specified by the above processing is arranged in time series and stored in the RAM 1112. For convenience, data in which the mobile device positions at a plurality of time points are arranged in time series will be referred to as movement trajectory data. This is because the data in which the mobile device positions at a plurality of time points are arranged in chronological order indicates the movement trajectory of the mobile device 200.

  In the present embodiment, the process of estimating the portable device position is terminated when the portable device position is estimated N times, but the present invention is not limited to this. For example, the position of the portable device may be estimated at a predetermined position confirmation interval until a predetermined event occurs such as when the user opens a door or presses the start button 130. However, in that case, in a situation where the user carrying the portable device 200 stays in the vicinity of the vehicle for a long time due to a conversation with a friend or the like, the power of the portable device 200 or the like continues to be consumed. On the other hand, according to the configuration in which the position estimation process of the portable device 200 is terminated at the maximum estimated number N as in the present embodiment, even when the user stays in the vicinity of the vehicle for a long time, the portable device 200 or the like. There is an effect that it is possible to avoid continuing to consume the power.

<Authentication-related processing>
Next, authentication-related processing including authentication processing performed by the authentication processing unit F7 will be described using the flowchart shown in FIG. The authentication-related process shown in FIG. 10 may be executed when the execution condition corresponding to the content of the vehicle control is satisfied. The execution conditions for the authentication process will be described later separately.

  First, in step S201, the authentication processing unit F7 generates a challenge code, transmits an LF signal (that is, a challenge signal) including the challenge code, and proceeds to step S202. Further, along with the generation of the challenge code, the authentication processing unit F7 generates a code obtained by encrypting the challenge code using the encryption key held by itself as a verification code. The challenge signal may be transmitted in order from each LF antenna 113, or may be configured to be transmitted only from the LF antenna 113 that has obtained a response to the polling signal.

  In the present embodiment, as an example, the polling signal and the challenge signal are different types of signals, but the present invention is not limited to this. By including a challenge code in the polling signal, the polling signal may function as a challenge signal. In other words, the challenge signal may be periodically transmitted as a polling signal. From the transmission of the signal including the challenge code to the verification of the code corresponds to the authentication process.

  In step S202, it is determined whether or not the authentication processing unit F7 has received a response signal. If a response signal can be received, an affirmative decision is made in step S202 and step S203 is executed. On the other hand, if the response signal cannot be received even after a predetermined response waiting time has elapsed since the challenge signal was transmitted, a negative determination is made in step S202 and the flow is terminated. In this case, authentication of the portable device 200 has failed.

  In step S203, the authentication processing unit F7 compares the response code returned from the portable device 200 with the verification code generated in step S201. When the response code returned from the portable device 200 matches the verification code, it is determined that the communication partner is the regular portable device 200 (that is, authentication is determined to be successful).

  In step S204, the authentication processing unit F7 determines whether or not the collation is successful as a result of the collation process in step S203. If the verification is not established, this flow is terminated. In this case, authentication of the portable device 200 has failed. On the other hand, when it becomes collation OK, it progresses to step S205. In this embodiment, as a more preferable aspect, when the collation is OK in step S <b> 204, the authentication processing unit F <b> 7 transmits an authentication success notification to the portable device 200 in cooperation with the LF transmission unit 112. Thereby, the portable device 200 vibrates the vibrator 230 with a predetermined vibration pattern.

  In step S205, the vehicle control unit F8 executes vehicle control determined according to the position of the portable device, etc., and ends this flow. For example, when a signal indicating that the portable device 200 is outside the vehicle compartment and is touched by the user from the touch sensor 120 is input, the door lock is unlocked. As described above, the content of the control processing performed by the authentication processing unit F7 when the authentication processing is successful may be content corresponding to the scene when the authentication processing is successful (in other words, the state of the vehicle). .

<Execution conditions for authentication processing>
Here, an example of the execution condition of the authentication process is disclosed. The execution condition of the authentication process is basically a matter to be designed according to the contents of the vehicle control to be executed when the authentication process is successful, in other words, the purpose of the authentication process. For example, the authentication process for unlocking the door lock of the vehicle when the vehicle is parked is executed when the position of the portable device specified by the position estimation unit F6 is within a predetermined authentication area. It only has to be done. The authentication area may be the vehicle communication area itself, or the authentication area may be set narrower than the vehicle communication area.

  The authentication process for starting the engine of the vehicle may be executed when the start button 130 is pressed in a state where the portable device 200 exists in the vehicle compartment and the brake pedal is depressed. Note that whether or not the portable device 200 exists in the vehicle interior may be determined by whether or not a response is obtained with respect to the response request signal transmitted from the vehicle interior antenna 113c.

  In the present embodiment, as a more preferable aspect, as shown in FIG. 11, the portable device 200 is relatively distant from the transmission area Za as an execution condition of the authentication process related to the vehicle control for unlocking the lock of the vehicle door. It is included that a movement trajectory indicating that it has reached the second area Ar2 that is an area relatively close to the LF antenna 113 is obtained after passing through the first area Ar1 that is an area. To do. The movement trajectory indicating that the portable device 200 has reached the second area Ar2 after passing through the first area Ar1 is before the time when the portable device 200 is detected to be present in the second area Ar2. This corresponds to a movement locus in which the portable device 200 is detected to be present in the first area Ar1. Px1, Px2, and Px3 in FIG. 11 represent the mobile device positions detected by the position estimation unit F6. Px1 and Px2 represent positions when the portable device 200 exists in the first area Ar1. Px3 represents a position when the portable device 200 exists in the second area Ar2.

  The first area Ar1 is an area separated from the LF antenna 113 by a predetermined area division distance Rx or more in the transmission area. The second area Ar2 is an area where the distance from the LF antenna 113 is less than the area division distance Rx in the transmission area. The second area Ar2 corresponds to the proximity area described in the claims, and the first area Ar1 corresponds to the intermediate area described in the claims.

  The area division distance Rx that defines the boundary line between the first area Ar1 and the second area Ar2 may be appropriately designed according to the reach distance of the LF signal. Here, as an example, it is assumed that the area division distance Rx is set to a value corresponding to ½ of the reach distance of the LF signal. In FIG. 11, the hatched area of the dot pattern having a relatively low density represents the first area Ar1, and the hatched area of the dot pattern having a relatively high density represents the second area Ar2. Represents. It should be noted that a movement locus indicating that the portable device 200 has reached the second area Ar2 after passing through the first area Ar1 is also obtained in the execution condition of the authentication process related to the vehicle control for starting the engine. Is included.

  According to such setting, even if the LF signal is relayed by the repeater, it is possible to reduce the possibility that the authentication process is executed and vehicle control such as unlocking the door is executed. When the radio wave transmitted from the in-vehicle system 100 is relayed by the repeater, the LF_RSSI has a very large value, and for the position estimation unit F6, the movement trajectory that the mobile device 200 suddenly appears in the second area Ar2. Is obtained. That is, the execution of unauthorized authentication processing is suppressed by setting the authentication processing to be executed only when the presence of the portable device 200 can be detected in each of the first area Ar1 and the second area Ar2. Can do.

<Summary of Embodiment>
In the above configuration, the vehicle-side control unit 111 specifies the distance D between the portable device 200 and the LF antenna 113 by obtaining LF_RSSI that is the reception intensity of the LF signal at the portable device 200 from the portable device 200. Further, by analyzing the received signal at the array antenna 114, the direction in which the portable device 200 exists is identified from the array antenna 114. Then, the portable device position is estimated by combining the distance D from the LF antenna 113 to the portable device 200 and the direction in which the portable device 200 exists.

  According to such an aspect, the detailed position of the portable device 200 within the transmission area can be specified. In addition, as another configuration for estimating the detailed position of the portable device 200, a configuration (hereinafter referred to as an assumed configuration) that uses reception strength (hereinafter referred to as UHF_RSSI) in the direction of the mobile device at the array antenna 114 instead of LF_RSSI. Conceivable.

  However, the inventors tested the correspondence between the reception intensity of the UHF band radio wave and the distance from the array antenna 114 to the portable device 200, and found that the reception intensity of the UHF band radio wave and the array antenna 114 to the portable device 200 were measured. It was found that the correlation with the distance was low. For example, even when the distance between the array antenna 114 and the portable device 200 is short, UHF_RSSI may be accidentally small due to radio wave superposition or the like, or even if the distance between the array antenna 114 and the portable device 200 is long. In some cases, UHF_RSSI is accidentally large due to radio wave superposition or the like. Therefore, the distance estimated from the reception intensity of radio waves in the UHF band has a large error, and as a result, there is a relatively high possibility that the position of the portable device is erroneously estimated in the assumed configuration.

  On the other hand, according to the configuration of the present embodiment, the distance from the portable device 200 is estimated based on LF_RSSI. Since the correspondence between LF_RSSI and distance is relatively clear, according to the configuration of the present embodiment, an error included in the estimated distance from the portable device 200 can be suppressed compared to the assumed configuration. That is, it can be said that this embodiment is more advantageous in terms of position estimation accuracy.

  In addition, according to the configuration of the present embodiment, the detailed position of the portable device 200 within the transmission area of the LF antenna 113 can be estimated. Therefore, an authentication area can be set in software inside the transmission area of the LF antenna 113. it can. That is, since the transmission area of the LF antenna 113 and the authentication area can be set separately, even if the transmission area of the LF antenna 113 is relatively widened, the authentication area itself can be limited to the vicinity of the vehicle as usual. . According to such an aspect, the communicable range between the in-vehicle system 100 and the portable device 200 is expanded, and various services can be realized by mutual communication between the in-vehicle system 100 and the portable device 200.

  Moreover, in said embodiment, the movement locus | trajectory of the user who is carrying the portable device 200 is specified by estimating a portable device position in multiple times. According to such a configuration, it is possible to provide a service according to the movement trajectory of the user. For example, when a trajectory from the front of the vehicle toward the trunk is obtained, vehicle control such as automatically opening the trunk can be performed.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to the above-mentioned embodiment, The various modifications described below are also contained in the technical scope of this invention, and also in addition to the following However, various modifications can be made without departing from the scope of the invention. For example, the following various modifications can be implemented in appropriate combination within a range where no technical contradiction occurs.

  In addition, about the member which has the same function as the member described in the above-mentioned embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted. In addition, when only a part of the configuration is mentioned, the configuration of the above-described embodiment can be applied to the other portions.

[Modification 1]
In the embodiment described above, the authentication processing unit F7 unlocks the door when the movement trajectory of the portable device 200 that has reached the second area Ar2 after passing through the first area Ar1 is obtained. Although the aspect set so that the authentication process which concerns on etc. was performed was disclosed, it is not restricted to this.

  The authentication processing unit F7 may be set to execute an authentication process related to unlocking the door or the like when a response to the polling signal is obtained regardless of the movement trajectory of the portable device 200. In such a setting, even if the authentication process is successful, the vehicle control unit F8 passes the first area Ar1 and then reaches the second area Ar2 as the movement locus of the portable device 200. It is preferable that the vehicle control for unlocking the door is not executed when the above is not obtained. Even with the configuration disclosed as the first modified example, it is possible to prevent a third party from unlocking the door or starting the engine illegally.

[Modification 2]
The portable device 200 transmits a signal including data indicating the detection result of the movement sensor 240 as a response signal, and the authentication processing unit F7 is included in the response state and the movement state of the portable device 200 indicated by the movement locus. The authentication process may be performed when the movement state of the portable device 200 indicated by the detection result of the movement sensor 240 is consistent. That is, the execution condition of the authentication process may include that the movement state of the portable device 200 indicated by the movement locus is consistent with the movement state of the portable device 200 indicated by the detection result of the movement sensor 240.

  Here, the moving state is, for example, whether or not it is moving. The case where the movement state of the portable device 200 indicated by the movement locus is consistent with the movement state of the portable device 200 indicated by the detection result of the movement sensor 240 included in the response signal is, for example, the portable device as the movement locus. 200 indicates that the mobile device 200 is moving, and the movement sensor 240 also detects that the portable device 200 is moving. In the case where data indicating that the portable device 200 is stopped as a movement locus is obtained, and the movement sensor 240 is also outputting data indicating that the portable device 200 is not moving, the movement is also performed. This corresponds to the case where the movement state of the portable device 200 indicated by the locus and the detection result of the movement sensor 240 is consistent. The detection result of the movement sensor 240 indicating that the portable device 200 is moving is data in which acceleration or angular velocity equal to or higher than a predetermined threshold is detected.

  If the movement sensor 240 is an acceleration sensor, the acceleration corresponding to the human walking is detected by the acceleration sensor, and the portable device 200 has a movement speed corresponding to the human walking speed. What is necessary is just to determine with the movement state of the portable device 200 which each of a movement locus | trajectory and the detection result of the movement sensor 240 match, when the data which are moving are obtained. Even with the above configuration, the risk of unauthorized authentication of the portable device 200 can be reduced.

[Modification 3]
In the above-described embodiment, the position of the portable device at one time point is determined by one position estimation process, but the present invention is not limited to this. The position of the portable device at a certain point in time may be determined based on the results of a plurality of position estimation processes. For example, the position estimation process may be performed three times in succession, and the center of gravity and average of the estimated positions for the three times may be adopted as the final portable device position. According to such an aspect, the position of the portable device can be estimated with higher accuracy.

[Modification 4]
In the above-described embodiment, when a plurality of candidates are detected as arrival directions, the direction having the highest received intensity is adopted as the direct wave direction, but the present invention is not limited to this. As shown in FIG. 12, the position estimation unit F6 in the present modification regards the direction of the highest received intensity as the direction of the portable device and newly estimates the portable device position (hereinafter, new estimated position) estimated so far. If it does not match the movement trajectory determined from the history of the portable device position, the direction of arrival having the second highest reception intensity is reset to the portable device direction, and the portable device position is re-estimated.

  Whether or not the new estimated position is consistent with the movement trajectory determined from the history of the mobile device position so far is determined by, for example, the distance from the new estimated position to a straight line (hereinafter referred to as a trajectory approximate line) approximately representing the movement trajectory. What is necessary is just to determine by whether it is less than a predetermined alignment determination threshold value. The locus approximate line may be, for example, a straight line that passes through the previous and previous estimated positions. Of course, the locus approximation line may be a curve passing through the past estimated position. When the distance from the new estimated position to the locus approximate line is less than the matching determination threshold, it is determined that the distance from the new estimated position to the locus approximate line is matched with the movement locus of the portable device 200 until then. If it is equal to or greater than the alignment determination threshold, it may be determined that the movement locus of the portable device 200 is not consistent.

  A specific example of the above idea will be described with reference to FIGS. Px1, Px2, and Px3 in FIG. 12 indicate the estimated positions of the portable device 200 when the number of transmission executions k = 1, 2, and 3 in order, and L3 is determined from the positions Px1, Px2, and Px3 of the portable device 200. The movement trajectory is shown. Px4 indicates the actual position of the portable device when the transmission execution count k = 4, and the solid line arrow starting from the position Px4 indicates the direct wave path. Further, an alternate long and short dash line arrow starting from the position Px4 indicates the reflection path of the response signal transmitted by the portable device 200 (that is, the path of the reflected wave). D4 in the figure represents the distance to the portable device 200 specified by the distance estimation unit F5 when the transmission execution count k = 4. The broken line to which the code | symbol Ln is provided represents the locus | trajectory approximation line. In FIG. 12, the thick lines passing through Px1 to P3 conceptually show the actual movement locus. For convenience, it is assumed that the distance from the position Px4a to the locus approximate line Ln is equal to or greater than the matching determination threshold value.

  As a result of estimating the direction of arrival by the array antenna, in many cases, the reception intensity of the direct wave (strictly, the intensity of the spectrum) is larger than the reception intensity of the reflected wave. Therefore, basically, the direction with the highest received intensity can be regarded as the direction of the portable device. However, the direct wave is attenuated by the user's body, or the direct wave overlaps with the reflected wave so that the reflected wave is incidentally received. Can occur.

  FIG. 13 shows the result of analyzing the reception result of the response signal from the portable device 200 when the transmission execution count k = 4 in the situation shown in FIG. θ1 is an angle corresponding to the arrival direction of the reflected wave indicated by a dashed line in FIG. 12, and θ2 is an angle corresponding to the arrival direction of the direct wave. As illustrated in FIG. 13, in this example, since the reception intensity of the reflected wave is larger than the reception intensity of the direct wave, the position estimation unit F6 once calculates the portable device position by regarding the direction θ1 as the portable device direction. To do. That is, as a result of the position estimation process when the transmission execution count k = 4, it is once estimated that the portable device 200 exists at the position indicated by Px4a in FIG.

  However, since the distance from the new estimated position Px4a to the locus approximate line Ln is equal to or greater than the matching determination threshold, the position estimation unit F6 discards the estimation result that the portable device 200 exists at the point Px4a and carries the direction θ2. Considering the machine direction, the portable device position is estimated again. Thereby, the new estimated position corresponding to the transmission execution count k = 4 can be matched with the point Px4 that is the position of the true portable device 200.

  In addition, since the event that the reception intensity of the reflected wave is higher than the reception intensity of the direct wave is an accidental event, the reception intensity of the direct wave is at least the second as an analysis result of the reception signal at the array antenna 114. It is highly possible that Therefore, according to said structure, possibility that the direction corresponding to a direct wave will be employ | adopted as a portable machine direction can be raised. In other words, according to the above aspect, even if the reception intensity of the reflected wave accidentally takes a value higher than the reception intensity of the direct wave, the portable device position is estimated as an incorrect position. Can be suppressed.

[Modification 5]
In the above-described embodiment, the mode in which the mobile device position is estimated using only the distance information derived from the reception strength (that is, LF_RSSI) of the LF signal in the mobile device 200 is disclosed, but the present invention is not limited thereto. The distance information derived from LF_RSSI is the distance of the portable device 200 specified by the distance estimation unit F5 according to LF_RSSI included in the response signal from the portable device 200. As another aspect, the position estimation unit F6 may estimate the portable device position using the reception intensity in the portable device direction specified by the direction estimation unit F4. Here, an example of a configuration corresponding to the above technical idea is disclosed.

  As shown in FIG. 14, the vehicle-side control unit 111 in this modification example estimates the distance from the array antenna 114 to the portable device 200 based on the reception intensity in the direction of the portable device from the direction estimation unit F4. Part F9 is provided. For the sake of convenience, in order to distinguish between the second distance estimation unit F9 introduced in the present modification and the distance estimation unit F5 that estimates the distance based on LF_RSSI described in the embodiment, the distance estimation unit F5 is referred to here. Is referred to as a first distance estimation unit F5. Further, since the reception intensity detected by the direction estimation unit F4 is the reception intensity of a response signal that is a radio signal in the UHF band, the reception intensity in the direction of the portable device is described as UHF_RSSI.

  The conversion from UHF_RSSI to distance information by the second distance estimation unit F9 is data indicating the correspondence between the distance between the array antenna 114 and the portable device 200 and the received signal strength of the response signal received by the portable device 200 ( Henceforth, what is necessary is just to implement using a UHF_RSSI map. It is assumed that the map storage unit M1 in this modification also holds a UHF_RSSI map in addition to the LF_RSSI map.

  Then, the position estimation unit F6 compares the first distance, which is the distance estimated by the first distance estimation unit F5, with the second distance, which is the distance estimated by the second distance estimation unit, and the difference between them is predetermined. If it is less than the allowable upper limit value, the position calculated by the method of the above embodiment is adopted as the portable device position and stored in the RAM 1112. On the other hand, when the difference between the first distance and the second distance is greater than or equal to the allowable upper limit value, it is determined that the portable device position is unknown. According to another viewpoint, when the difference between the first distance and the second distance is equal to or larger than the allowable upper limit value, the estimation of the position of the portable device 200 is put on hold.

  The allowable upper limit value only needs to be set to a value larger than at least the distance from the array antenna 114 to the LF antenna 113, and the specific value may be designed as appropriate. Further, the allowable upper limit value only needs to be able to distinguish between the case where the portable device 200 exists at a position 10 m or more away from the array antenna 114 and the case where it exists in the transmission area. Therefore, the allowable upper limit value may be a value similar to the distance (here, 5 m) from the center of the transmission area to the farthest part, such as 5 m or 10 m, for example.

  As described above, the distance estimated from the reception intensity of the radio wave in the UHF band has a relatively large error. The allowable upper limit value is preferably set to a value that can sufficiently absorb an error that may occur in the distance estimated from the reception intensity of radio waves in the UHF band. An error that may occur in the distance estimated from the reception intensity of the radio wave in the UHF band may be specified by an actual test. If the average value of errors that can occur in the distance estimated from the received intensity of radio waves in the UHF band is 3 m, and the distance from the array antenna 114 to the LF antenna 113 is 1 m, the allowable upper limit value is 4 m or more. It is preferable that it is set.

[Modification 6]
In the above description, the portable device 200 is configured to return a response signal only once with respect to reception of one position estimation signal. However, the present invention is not limited to this. The portable device 200 may be configured to continuously transmit a response signal a plurality of times (for example, three times) in response to one reception of the position estimation signal. A plurality of response signals transmitted continuously with respect to one reception of the position estimation signal may be signals having the same content. The mode of continuous transmission includes a mode of intermittent transmission with a minute interval of about several milliseconds to several tens of milliseconds.

  According to such a configuration, the in-vehicle system 100 receives the response signal a plurality of times in response to one transmission of the position estimation signal. If such an operation is used, the estimation accuracy of the portable device position by the position estimation unit F6 can be increased.

  For example, the direction estimation unit F4 calculates the reception strength for each arrival direction every time the UHF reception unit 115 receives a response signal, and extracts the direction having the highest reception strength each time as a candidate for the portable device direction. Then, the direction with the largest number of times calculated as a candidate for the portable device direction is adopted as the portable device direction. According to such an aspect, it is possible to reduce the risk of setting the mobile device direction to a direction different from the actual direction. As a result, it is possible to improve the estimation accuracy of the portable device position by the position estimation unit F6.

  In addition, the configuration as the sixth modification can be applied to the fifth modification. In that case, the second distance estimation unit F9 calculates the second distance a plurality of times for one transmission of the position estimation signal. As a premise, the direction estimation unit F4 calculates the reception intensity for each arrival direction every time the UHF reception unit 115 receives a response signal. The second distance estimation unit F9 is configured to calculate the second distance based on the reception strength in the direction of the portable device every time the direction estimation unit F4 calculates the reception strength for each direction. .

  Then, the second distance estimation unit F9 uses a plurality of second distances calculated from a single transmission of the position estimation signal as a population, and represents a value representative of the second distances (hereinafter referred to as the first distance). 2 distance representative value) is calculated. The second distance representative value may be an average value of a plurality of second distances or a median value. If the difference between the first distance and the second distance representative value is less than the allowable upper limit value, the position estimation unit F6 employs the position calculated by the method of the above embodiment as the portable device position. On the other hand, when the difference between the first distance and the second distance representative value is greater than or equal to the allowable upper limit value, it is determined that the position of the portable device is unknown. According to the above configuration, it is possible to reduce an error included in the second distance, and thus it is possible to reduce a possibility that the position of the portable device is determined to be unknown due to an estimation error of the second distance.

[Modification 7]
As described above, the approach detection unit F3 has disclosed the mode of detecting that the distance between the vehicle and the portable device is within the predetermined estimated execution distance when the response signal to the polling signal in the LF band is received. Not limited to. When both the in-vehicle system 100 and the portable device 200 are configured to be able to transmit and receive UHF band signals, the UHF band response request signal is transmitted from the in-vehicle system 100 to the portable device 200, and the response request signal is transmitted. The distance may be estimated on the basis of the reception intensity of the response signal to the response (that is, UFH_RSSI), and it may be detected that the distance between the vehicle and the portable device is within a predetermined estimated execution distance. In addition, when both the in-vehicle system 100 and the portable device 200 are configured to be capable of short-range wireless communication, the distance between the vehicle and the portable device 200 based on the communication status in the short-range wireless communication with the portable device 200. May be detected to be within a predetermined estimated execution distance.

[Modification 8]
In the above-described embodiment, a mode in which a signal indicating LF_RSSI as it is is returned as a response signal is disclosed, but the present invention is not limited to this. The portable device 200 may have an LF_RSSI map, and the portable device 200 may be configured to return a signal indicating a distance according to LF_RSSI as a response signal. Data indicating LF_RSSI and data indicating a distance determined from LF_RSSI correspond to the distance related information described in the claims. Note that LF_RSSI itself corresponds to distance-related information that indirectly indicates the distance from the portable device 200 to the LF antenna 113.

[Modification 9]
In the above-described embodiment, the mode of transmitting the position estimation signal using the LF band radio wave is disclosed, but the present invention is not limited to this. If it is about 1 MHz, a point at 48 m from the antenna becomes the boundary between the near field and the far field. That is, since the range within 5 m from the vehicle for a 1 MHz radio wave is sufficiently near field, the strength of the position estimation signal transmitted by the in-vehicle system 100 is sharply attenuated by the cube of the distance. In view of such circumstances, the first frequency may be 1 MHz or less.

DESCRIPTION OF SYMBOLS 100 In-vehicle system, 200 Portable apparatus, 111 Vehicle side control part, 112 LF transmission part (onboard equipment side transmission part), 113 * 113a-c LF antenna (vehicle-mounted antenna), 114 array antenna, 114a-c UHF antenna, 115 UHF Receiver (on-vehicle device side receiver), 210 LF communication module (portable device side receiver), 211 LF antenna, 212 LF receiver, 213 RSSI circuit, 220 UHF communication module (portable device side transmitter), 221 UHF antenna , 222 UHF transmission unit, 230 vibrator, 240 movement sensor, 260 portable device side control unit, F3 approach detection unit, F4 direction estimation unit, F5 distance estimation unit (first distance estimation unit), F6 position estimation unit, F7 authentication processing Unit, F8 vehicle control unit, F9 second distance estimation unit, M1 map storage unit, G 1 reception data acquisition unit, G2 LF_RSSI acquisition unit, G3 response processing unit, G4 notification processing unit

Claims (10)

An on-vehicle device (110) mounted on a vehicle, and a portable device (200) associated with the on-vehicle device and carried by a user of the vehicle,
The portable device is
A portable device receiving unit (210) for receiving a response request signal, which is a radio signal for requesting the portable device to return a response signal, transmitted from the vehicle-mounted device using radio waves of a predetermined first frequency; ,
A portable device side strength acquisition unit (213) for acquiring a portable device side strength that is a received signal strength of the response request signal received by the portable device side receiving unit;
The response signal includes distance-related information that directly or indirectly indicates a distance from the portable device to the transmission source of the response request signal, which is determined from the portable device-side strength acquired by the portable device-side strength acquisition unit. A portable device-side transmitter (220) that transmits a signal using radio waves of a predetermined second frequency higher than the first frequency,
The in-vehicle device is
A vehicle-mounted device side transmission unit (112) that transmits the response request signal from a vehicle-mounted antenna (113) that is an antenna for transmitting the radio wave of the first frequency mounted on the vehicle;
An on-vehicle device side receiving unit (115) for receiving the response signal via an array antenna (114) for receiving radio waves of the second frequency;
A direction estimation unit (F4) that estimates a direction in which the response signal arrives based on a reception result of the response signal at the array antenna;
A distance estimation unit (F5) for estimating a distance from the vehicle-mounted antenna to the portable device based on the distance-related information included in the response signal received by the vehicle-mounted device-side reception unit;
A position estimation unit that estimates the position of the portable device based on the arrival direction of the signal from the portable device estimated by the direction estimation unit and the distance from the vehicle-mounted antenna to the portable device estimated by the distance estimation unit. (F6). A portable device position estimation system comprising: The portable device position estimation system according to claim 1,
The direction estimation unit identifies reception strength for each direction by analyzing a reception result of the response signal at the array antenna,
The position estimation unit adopts the direction with the strongest reception strength among the reception strengths for each direction estimated by the direction estimation unit, as a portable device direction in which the portable device exists,
In addition to the first distance estimation unit serving as the distance estimation unit, the on-vehicle device estimates a distance of the portable device based on a reception intensity of the response signal in the portable device direction (F9). With
The position estimation unit has a difference between a first distance that is a distance estimated by the first distance estimation unit and a second distance that is a distance estimated by the second distance estimation unit is less than a predetermined allowable upper limit value. In this case, the position estimated using the first distance is adopted as the position of the portable device, while the difference between the first distance and the second distance is greater than or equal to the allowable upper limit value. A portable device position estimation system characterized by determining that the position of a machine is unknown. The portable device position estimation system according to claim 2,
The portable device is configured to continuously transmit the response signal a plurality of times in response to receiving the response request signal once.
The second distance estimator is
Calculating the second distance each time the response signal is received;
Based on a plurality of the second distances calculated from a single transmission of the response request signal, a second distance representative value that is a value representing the plurality of second distances is calculated,
When the difference between the second distance representative value and the first distance is less than the allowable upper limit value, the position estimated using the first distance is adopted as the position of the portable device, while the first A portable device position estimation system, wherein a position of the portable device is determined to be unknown when a difference between a distance and the second distance representative value is greater than or equal to the allowable upper limit value. The portable device position estimation system according to any one of claims 1 to 3,
The on-vehicle device includes an approach detection unit (F3) that detects that the distance from the portable device is within a predetermined estimated execution distance based on the communication status with the portable device,
The position estimation unit
Position estimation is a process of estimating the position of the portable device a plurality of times at a predetermined position confirmation interval from when the proximity detection unit detects that the distance from the portable device is within the estimated execution distance. Process,
A portable device position estimation system, wherein movement locus data, which is data indicating a movement locus of the portable device, is generated by arranging a plurality of times of the position estimation processing results in time series. The portable device position estimation system according to claim 4,
The direction estimation unit identifies reception strength for each direction by analyzing a reception result of the response signal at the array antenna,
The position estimation unit
Of the reception strengths for each direction estimated by the direction estimation unit, the direction with the strongest reception strength is provisionally set to the mobile device direction that is the direction in which the mobile device exists,
Whether the new estimated position, which is the position of the portable device obtained as a result of the newly executed position estimation process, is consistent with the movement trajectory of the portable device determined from the result of the position estimation process performed so far Determine whether or not
When it is determined that the new estimated position is not consistent with the movement trajectory of the portable device determined from the result of the position estimation process performed up to the previous time, the second received intensity detected by the direction estimation unit The portable device position estimation system is characterized in that the position of the portable device is estimated by resetting the direction with the strongest direction to the portable device direction. The mobile device position estimation system according to claim 4 or 5,
The in-vehicle device is
An authentication processing unit (F7) that performs authentication processing that is processing for authenticating that the portable device is the portable device associated with the vehicle by performing wireless communication with the portable device;
The authentication processing unit is configured such that the distance from the in-vehicle antenna is the area after the portable device passes through an intermediate area set at a position separated from the in-vehicle antenna by a predetermined area division distance or more. The portable device position estimation system, wherein the authentication process is executed when the movement trajectory indicating that a proximity area that is an area that is less than the division distance has been acquired. The mobile device position estimation system according to claim 4 or 5,
An authentication processing unit (F7) that performs authentication processing that is processing for authenticating that the portable device is the portable device associated with the vehicle by performing wireless communication with the portable device;
A vehicle control unit (F8) that executes predetermined vehicle control based on the success of the authentication process,
Even if the authentication process is successful, the vehicle control unit passes through an intermediate area in which the portable device is set at a position separated from the vehicle by a predetermined area division distance or more as the movement trajectory. The vehicle control is not executed when the movement locus indicating that the distance from the vehicle has reached the proximity area that is an area that is less than the area division distance cannot be acquired. Mobile device position estimation system. The portable device position estimation system according to any one of claims 4 to 7,
An authentication processing unit (F7) that performs authentication processing that is processing for authenticating that the portable device is the portable device associated with the vehicle by performing wireless communication with the portable device;
The portable device is
A movement sensor (240) for detecting that the portable device is moving;
The portable device side transmission unit transmits a signal including data indicating a detection result of the movement sensor as the response signal,
The authentication processing unit, when the movement state of the portable device indicated by the movement locus matches the movement state of the portable device indicated by the detection result of the movement sensor included in the response signal A portable device position estimation system that performs an authentication process. The portable device position estimation system according to any one of claims 1 to 8,
An authentication processing unit (F7) that performs authentication processing that is processing for authenticating that the portable device is the portable device associated with the vehicle by performing wireless communication with the portable device;
When the authentication process by the authentication processing unit is successful, the on-vehicle device side transmission unit transmits an authentication success notification signal indicating that the authentication process is successful to the portable device,
The portable device is
A notification device (230) for notifying the user of information;
When the portable device side receiving unit receives the authentication success notification signal, the portable device side receiving unit includes a notification processing unit (G4) that performs a process of notifying that the authentication processing is successful in cooperation with the notification device. A portable device position estimation system characterized by The portable device position estimation system according to any one of claims 1 to 9,
The first frequency is a frequency of 1 MHz or less;
The in-vehicle antenna is a magnetic field antenna,
The transmission power of the signal at the vehicle-mounted antenna is set to a level at which the response signal is not returned when the portable device is 10 m or more away from the vehicle-mounted antenna.

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