VEHICLE AUTHENTICATION DEVICE

Abstract

A vehicle authentication device including a plurality of mobile devices each serving as a key of a vehicle, the vehicle authentication device comprising: a first communication device (12) configured to determine a first area set in advance for the vehicle as a communication area; a second communication device (13) configured to determine a second area, which is set in advance for the vehicle and does not overlap with the first area, as the communication area; a first area determining device (F3) configured to determine whether the mobile devices are present in the first area based on a communication state between the first communication device and the mobile devices; a second area determining device (F4) configured to determine whether the mobile devices are present in the second area based on a communication state between the second communication device and the mobile devices; a control execution device (F5) configured to execute a predetermined vehicle control in response to the first area determining device determines that none of the mobile devices is present in the first area; and the second area determining device determines that at least one of the mobile devices is present in the second area, wherein the first area determining device is further designed transmit a simultaneous response request signal for simultaneously requesting the mobile devices to return respective response signals in collaboration with the first communication device; and in response to the first area determining device not receiving the response signals corresponding to the simultaneous response request signal originating from the mobile devices, respectively, determining that the mobile devices are not present in the first area, and wherein the second area determining device is further designed requesting the mobile devices in collaboration with the second communication device to return the response signals at different return times that do not overlap; and in response to the second area determining device receiving at least one of the response signals originating from the mobile devices, respectively, to determine that the at least one of the mobile devices is present in the second area.

Description

Cross-reference to the relevant application

[0001] This application is based on Japanese patent application JP 2018 - 97 178 filed on May 21, 2018, the disclosure of which is hereby incorporated by reference. Technical area

[0002] The present invention relates to a vehicle authentication device that performs predetermined vehicle control such as door locking by wireless communication with a mobile device as an electronic key. State of the art

[0003] A vehicle authentication device performs vehicle control such as door locking, door unlocking, or engine activation in response to establishing a wireless connection with a mobile device carried by a user and confirming that the mobile device is present within a predetermined area. The mobile device is a so-called smart key. For example, the vehicle authentication device locks all doors of a vehicle in response to confirming that the mobile device is present within the predetermined area outside the vehicle cabin (hereinafter referred to as the lock area) by wireless communication in a situation where a lock switch arranged on the outer surface of a vehicle body receives a lock command.

[0004] In a situation where the vehicle authentication device executes the control for locking the vehicle doors, the vehicle authentication device not only confirms that the mobile device is present in the locking range to confirm that the mobile device is not locked in the vehicle cabin. The vehicle authentication device also executes the door locking control by wireless communication in a situation where the vehicle authentication device confirms that the mobile device is not present inside the vehicle cabin. Wireless communication is used to confirm that the mobile device is not present inside the vehicle cabin. Wireless communication is executed multiple times when a response signal from the mobile device cannot be received due to a communication error.Specifically, the vehicle authentication device transmits a response request signal to the mobile device multiple times to request the return of the response signal, and confirms the determination that the mobile device is not present inside the vehicle cabin in a situation where no response signals are returned to the response request signals. Therefore, a considerable amount of time is required for a series of communication processes (hereinafter referred to as an absence confirmation process) to determine that the mobile device is not present inside the vehicle cabin.

[0005] Generally, multiple devices (e.g., two or three) are issued for a vehicle in different situations. To determine that none of the mobile devices is present inside the vehicle cabin, the vehicle authentication device must perform the absence confirmation process for each of the mobile devices. Consequently, it takes longer to complete locking the vehicle in response to a user's locking instruction. This situation may be inconvenient for a user.

[0006] To solve the problems described above, JP 5 350 719 B2 discloses a configuration for improving the responsiveness to a user's lock command by starting the absence confirmation process at the time of closing a door (in other words, before pressing the lock switch). State of the art literaturePatent literature

[0007] PTL 1: JP 5 350 719 B2 Summary of the invention

[0008] In a method for confirming the absence of mobile devices within a vehicle cabin by individually performing wireless communication with a plurality of mobile devices (hereinafter referred to as the individual confirmation method), the time required to confirm the absence of the mobile devices within the vehicle cabin (hereinafter referred to as the absence determination required time) depends on the number of mobile devices. In other words, the absence determination required time is longer as the number of mobile devices is larger.

[0009] As described in JP 5 350 719 B2, according to a configuration that starts the absence confirmation process when a door is closed, it is possible to reduce the possibility that the responsiveness to a user's lock instruction caused by the absence determination required time decreases. However, even if the absence confirmation process starts at a time when the door is closed, if the user issues a door lock instruction immediately after the door is closed, a part of the absence determination required time is included in a timer period from the user's lock instruction to the completion of locking. Consequently, the responsiveness to the user's lock instruction may decrease.When using such an individual confirmation method, the above situation is likely to occur because the absence determination requirement time is longer when the number of devices is larger.

[0010] A reduction in user convenience caused by the absence determination required time is not limited to a vehicle control regarding door locking, but may also occur in the execution of other vehicle control using an execution condition according to which none of the mobile devices are present in a predetermined area.

[0011] The present invention provides a vehicle authentication device used in a vehicle having a plurality of mobile devices. The vehicle authentication device can prevent or reduce the absence determination required time as a time for determining that the mobile devices are not present in a predetermined area, and can reduce the lengthening of the absence determination required time associated with an increase in the number of mobile devices.

[0012] A vehicle authentication device according to one aspect of the present invention is used in a vehicle having a plurality of mobile devices each serving as a key of the vehicle. The vehicle authentication device includes a first communication device, a second communication device, a first area designation device, a second area designation device, and a control execution device. The first communication device designates a first area as a communication area, and the first area is set in advance for the vehicle. The second communication device designates a second area as the communication area, and the second area is set in advance for the vehicle and does not overlap with the first area.The first area determining device determines whether the mobile devices are present in the first area based on a communication state between the first communication device and the mobile devices. The second area determining device determines whether the mobile devices are present in the second area based on a communication state between the second communication device and the mobile devices. The control executing device executes predetermined vehicle control in response to: the first area determining device determining that none of the mobile devices are present in the first area; and the second area determining device determining that at least one of the mobile devices is present in the second area.The first area determining device transmits a simultaneous response request signal requesting the mobile devices to simultaneously return response signals, respectively, in cooperation with the first communication device, and determines that the mobile devices are not present in the first area in response to the first area determining device not receiving the response signals from the respective mobile devices according to the simultaneous response request signal. The second area determining device requests the mobile devices in cooperation.Collaboration with the second communication device to return the response signals at different return times that do not overlap, and in response to the second area determining device receiving at least one of the response signals from the respective mobile devices, determines that the at least one of the mobile devices is present in the second area.

[0013] The first area determining device in the above configuration transmits the simultaneous response request signal to detect that the mobile devices are not present in the first area, and the second determining device in the above configuration transmits the time difference response request signal to detect that the mobile devices are present in the second area.

[0014] In the above configuration, in a situation where the mobile device is present in the first area, the vehicle cabin interior determination device can receive the response signal from the mobile device after transmitting the simultaneous response request signal. On the other hand, in a situation where the mobile device is not present in the first area, the vehicle cabin interior determination device does not receive the response signal from the mobile device after transmitting the simultaneous response request signal. In other words, the situation where the response signal is not received from the mobile device in a waiting period for receiving the response signal to the simultaneous response request signal suggests that the mobile device is not present in the first area.

[0015] Since the simultaneous response request signal simultaneously requests multiple mobile devices to return the response signal, the timing of the return of the response signals from the mobile devices that received the simultaneous response request signal is substantially the same. Therefore, after transmitting the simultaneous response request signal, the time required for the first area determination device to wait for the response from the mobile device(s) is constant regardless of the number of mobile devices. Therefore, it is possible to prevent the absence determination required time Tp from increasing as the number of mobile devices increases.

[0016] The first area determination device does not individually perform wireless communication with a plurality of mobile devices. The first area determination device determines that no mobile device is present in the first area based on the condition that the response signal is not received as a result of simultaneously requesting the mobile devices to return the response signal. Therefore, it is possible to reduce the absence determination required time compared to the configuration (hereinafter referred to as the adopted configuration) in which the absence of the mobile devices in the first area is determined by individually performing communication with the mobile devices respectively. In other words, according to the above configuration, it is possible to prevent an extension of the absence determination required time caused by an increase in the number of mobile devices. Short description of the drawings Fig. 1 is a diagram showing a schematic configuration of an electronic vehicle key system. Fig. Figure 2 is a block diagram showing an electrical configuration of a smart (electronic) key. Fig. 3 is a block diagram showing an electrical configuration of an on-vehicle system. Fig. Figure 4 is a diagram conceptually showing a response range provided by each vehicle external transmitter. Fig. 5 is a functional block diagram of an authentication ECU. Fig. 6 is a flowchart of a door locking process executed by the authentication ECU. Fig. Figure 7 is a flowchart of a process for confirming that the smart key is present outside the vehicle cabin. Fig. 8 is a diagram illustrating the operation of each device in executing the process for confirming the smart key in a situation where the smart key is present in a locking area. Fig. 9 is a flowchart of a process for confirming that the smart key is not present inside the vehicle cabin. Fig. 10 is a diagram illustrating the operation of each device in executing the process for confirming that the smart key is not present inside the vehicle cabin in a situation where there is no smart key inside the vehicle cabin. Fig. 11 is a diagram illustrating the operation of each device in executing the process for confirming that the smart key is not present inside the vehicle in a situation where there is only a single smart key inside the vehicle cabin. Fig. 12 is a diagram illustrating the operation of each device in executing the process for confirming that the smart key is not present inside the vehicle cabin in a situation where a plurality of smart keys are present inside the vehicle cabin. Fig. Figure 13 is a diagram showing a comparison configuration. Fig. 14 is a diagram illustrating the operation of the authentication ECU according to a first modification example. Fig. 15 is a diagram illustrating the operation of the authentication ECU according to a second modification example. Fig. 16 is a flowchart of a door locking process executed by the authentication ECU according to a third modification example. Embodiments for carrying out the invention

[0017] Embodiments of the present invention will now be described with reference to the drawings. Fig. 1 is a diagram showing an example of a schematic configuration of an electronic vehicle key system 100 of the present embodiment. As shown in Fig. 1, the vehicle electronic key system 100 includes an on-vehicle system 1 mounted on a vehicle Hv and smart keys 2a to 2c carried by the user of the vehicle Hv. Each of the smart keys 2a to 2c is associated with the on-vehicle system 1 and is a mobile device serving as a key (specifically, an electronic key) of the vehicle Hv. Each of the smart keys 2a to 2c may also be simply referred to as a smart key 2 when there is no need to distinguish between the smart keys 2a to 2c. The number of smart keys 2 associated with the on-vehicle system 1 is not limited to three. The number of smart keys 2 may be, for example, two or four.

[0018] The in-vehicle system 1 and the smart keys 2 each include a configuration for performing wireless communication using radio waves in a predetermined frequency band. Specifically, the in-vehicle system 1 transmits a signal having a predetermined frequency belonging to the LF (low frequency) band toward a predetermined area inside the vehicle cabin and around the vehicle, and receives a signal in a UHF (ultra high frequency) band transmitted from the smart key 2. The smart key 2 receives a signal in the LF band transmitted from the in-vehicle system 1 and returns a signal having a predetermined frequency belonging to the UHF band to the in-vehicle system 1. In this example, the LF band refers to a frequency band of 300 kHz or less and includes a frequency of 20 kHz to 30 kHz or the like.In this example, the UHF band refers to 300 MHz to 3 GHz.

[0019] The frequency in the LF band used to transmit a signal from the on-vehicle system 1 to the smart key 2 in the vehicle electronic key system 100 is, for example, 125 kHz or 134 kHz. The frequency in the UHF band used to transmit a signal from the smart key 2 to the on-vehicle system 1 is, for example, 315 MHz or 920 MHz. As one of the examples described here, 125 kHz is used as a frequency used to transmit a signal from the on-vehicle system 1 to the smart key 2. 315 MHz is used as a frequency used to transmit a signal from the smart key 2 to the on-vehicle system 1. The description here describes that the on-vehicle system 1 and the smart key 2 perform two-way wireless communication by using radio waves in the LF band and the UHF band.However, it is also possible to modify the frequency for the vehicle's own system 1 and the smart key 2 to perform wireless communication.

[0020] The on-vehicle system 1 authenticates the smart key 2 via mutual wireless communication with the smart key 2. The on-vehicle system 1 executes a predetermined vehicle control for the user to use the vehicle Hv based on the successful authentication of the smart key 2. The vehicle control for using the vehicle Hv can be, for example, a door locking, an unlocking, or an engine activation.

[0021] The process for the on-vehicle system 1 to authenticate the smart key 2 is a process for confirming a communication terminal (hereinafter referred to as the communication target) that is an authorized smart key 2 associated with the on-vehicle system 1. The communication terminal performs wireless communication with the on-vehicle system 1. Successful authentication corresponds to a determination that the communication terminal is the authorized smart key 2.

[0022] Authentication of the smart key 2 via the in-vehicle system can be performed, for example, using a challenge-response method. The details of the authentication process are described below. In preparation for the authentication process, a common encryption key used for the authentication process is stored in each of the smart key 2 and the in-vehicle system 1. In addition, a unique identification number (hereinafter referred to as key ID) is assigned to the smart key 2, and the key ID is registered in the in-vehicle system 1. The key ID is unique for each smart key. The encryption key used for the authentication process can also be the key ID.A unique identification number (hereinafter referred to as vehicle ID) is also assigned to the vehicle's own system 1, and the vehicle ID is registered in the smart key 2.

[0023] As an example of the present embodiment, the vehicle Hv is an internal combustion engine vehicle that has only an internal combustion engine as a power source. However, the vehicle Hv may be a so-called hybrid vehicle that includes an internal combustion engine and an electric motor as power sources, or may be an electric vehicle that has only an electric motor as a power source. Configuration of the smart key 2

[0024] The following describes the configuration of the smart key 2. The smart key 2 contains a key-side receiver 21, a key-side controller 22 and a key-side transmitter 23, as shown in Fig. 2. The key-side controller 22 is communicatively connected to the key-side receiver 21 and the key-side transmitter 23.

[0025] The key-side receiver 21 receives a wireless signal (hereinafter referred to as an LF signal) of a predetermined frequency (125 kHz in this example) belonging to the LF band transmitted from the on-vehicle system 1. The key-side receiver 21 may use an antenna for receiving the LF signal or a circuit (so-called demodulation circuit) for demodulating the received signal. The key-side receiver 21 subjects the signal received via the antenna to predetermined processing such as analog-to-digital conversion, demodulation, and decoding to extract data included in the received signal. The extracted data is provided to the key-side controller 22.

[0026] The key-side controller 22 receives the received signal from the key-side receiver 21, generates a baseband signal corresponding to a response signal corresponding to the received signal, and outputs the baseband signal to the key-side transmitter 23. For example, in a situation where the key-side receiver 21 receives a response request signal transmitted from the on-vehicle system 1, the key-side controller 22 generates a baseband signal as a response signal corresponding to the content of the received response request signal and outputs the baseband signal to the key-side transmitter 23. The baseband signal as the corresponding response signal is processed with a predetermined modulation process at the key-side transmitter 23 and transmitted as the wireless signal.

[0027] The key-side controller 22 generates the baseband signal containing a response kernel generated by using an encryption key registered in advance in the smart key 2 in a situation where the response request signal containing the challenge code (mentioned later) transmitted from the on-vehicle system 1 is received. The baseband signal containing the response code generated by the key-side controller 22 is output to the key-side transmitter 23 and transmitted therefrom as the wireless signal.

[0028] The key-side controller 22 may use a computer including, for example, a CPU, RAM, and ROM. The key-side controller 22 may use one or more integrated circuits (ICs). The key-side controller 22 may use an MPU or GPU.

[0029] The key-side transmitter 23 transmits the wireless signal at the predetermined frequency (in this example, 315 MHz) belonging to the UHF band to the on-vehicle system 1. The key-side transmitter 23 converts a signal obtained by performing modulation or frequency conversion on the baseband signal received by the key-side controller 22 into a radio wave and then transmits the radio wave into the room. The key-side transmitter 23 uses an antenna or a modulation circuit. The wireless signal transmitted by the key-side transmitter 23 may also be referred to as an RF signal. RF is an abbreviation for radio frequency.

[0030] The smart key 2 may be a device carried by the user and has a function as an electronic key of the vehicle Hv. Specifically, the function as an electronic key of the vehicle Hv is a function of returning a signal (e.g., a response code) containing information proving that it is the key of the vehicle Hv based on a request from the in-vehicle system 1. A variety of shapes, such as a flat rectangular parallelepiped shape, a flat elliptical body shape (so-called fob type), and a card type, may be used as the shape of the smart key 2. The smart key 2 may be configured as a wearable device worn on a user's finger, arm, or the like. Furthermore, the smart key 2 may be an information processing terminal, such as a smartphone or a tablet. Configuration of the vehicle's own system 1

[0031] The following describes the configuration of the on-vehicle system 1. The on-vehicle system 1 includes an authentication ECU 11, a vehicle cabin interior transmitter 12, a vehicle cabin exterior transmitter 13, a receiver 14, a lock button 15, and a body ECU 16, as shown in Fig. 3. ECU in the element names is an abbreviation for "Electronic Control Unit" and refers to an electronic control unit. The on-vehicle system 1 corresponds to a vehicle authentication device.

[0032] The authentication ECU 11 is an ECU that executes the control process related to locking the door of the vehicle Hv, such as the door locking process described below. The authentication ECU 11 is connected to each of the authentication ECU 11, the in-vehicle cabin transmitter 12, the out-of-vehicle cabin transmitter 13, the receiver 14, the lock button 15, and the body ECU 16 via a dedicated signal line. The body ECU 16 can communicate with the authentication ECU 11 via a vehicle-mounted communication network. The same applies, for example, to the in-vehicle cabin transmitter 12, the out-of-vehicle cabin transmitter 13, the receiver 14, and the lock button 15. The receiver 14 can be built into the authentication ECU 11.

[0033] The authentication ECU 11 is configured as a computer including a CPU 111, a flash memory 112, a RAM 113, an I / O (input / output) interface, and a bus line connecting these components. The authentication ECU 11 can be implemented using a GPU or an MPU instead of the CPU 111. Furthermore, the authentication ECU 11 can be implemented by a combination of a CPU 111, a GPU, and an MPU.

[0034] The flash memory 112 is a non-volatile and rewritable memory. The flash memory 112 stores a program (hereinafter referred to as an authentication device program) for causing the computer to function as an authentication ECU 11 and the like. Various non-volatile tangible storage media (non-volatile tangible storage medium) can be used as a dedicated storage medium of the authentication device program. Execution of the authentication device program via the CPU 111 corresponds to execution of a process corresponding to the authentication device program. The details of the functions provided by the authentication ECU 11 and mentioned when the CPU 111 executes the authentication device program will be described later.

[0035] The in-vehicle cabin transmitter 12 converts a carrier wave signal received from the authentication ECU 11 into a radio wave of a predetermined frequency (125 kHz in this example) belonging to the LF band and transmits the radio wave into the room. For convenience, the configuration in which the carrier signal received by the authentication ECU 11 is converted into the radio wave of a predetermined frequency belonging to the LF band and transmitted into the room is also referred to as an LF transmitter. The in-vehicle cabin transmitter 12 is the LF transmitter arranged inside the vehicle cabin, so that the entire vehicle cabin interior is the response area. The vehicle cabin interior corresponds to a first area.

[0036] The response range corresponds to a range in which the smart key 2 returns a response signal to the LF band signal (hereinafter referred to as LF signal) transmitted from the LF transmitter. The response range may be, for example, a range in which the LF signal transmitted by the in-vehicle system 1 propagates while maintaining a predetermined signal strength (hereinafter referred to as response threshold). The response threshold corresponds to a signal strength of the LF signal, which defines the strength of the response range. The response threshold may be, for example, a lower limit value (i.e., a demodulation threshold) of a signal level that can be demodulated by the smart key 2. The response threshold may be a predetermined value greater than the demodulation threshold.The response threshold is a value appropriately determined by a developer to establish the desired response range. Even if the smart key 2 receives a signal from the on-vehicle system 1, the smart key 2 determines that the signal is outside the response range and does not return a response if the signal strength is less than or equal to the response threshold. The response range corresponds to a communication range.

[0037] The vehicle cabin interior transmitter 12 may be arranged at a central portion in the vehicle width direction of a dashboard or near a center console. Even if in the Fig. 3 and Fig. 4 only a single vehicle cabin interior transmitter 12 is shown, several vehicle cabin interior transmitters 12 can be arranged in the vehicle cabin interior. In Fig. 4, the representation of the response range of the vehicle cabin interior transmitter 12 is omitted.

[0038] The vehicle cabin exterior transmitter 13 is an LF transmitter for setting a predetermined area outside the vehicle cabin as a response area. The vehicle cabin exterior transmitter 13 converts the carrier wave signal received from the authentication ECU 11 into a radio wave of the predetermined frequency belonging to the LF band. The on-vehicle system 1 includes a plurality of vehicle cabin exterior transmitters 13. As an example of the present embodiment, a first vehicle cabin exterior transmitter 13A, a second vehicle cabin exterior transmitter 13B, and a third vehicle cabin exterior transmitter 13C are arranged as the vehicle cabin exterior transmitter 13 on the vehicle Hv, as shown in Fig. 4 is shown.

[0039] The first vehicle cabin exterior transmitter 13A is an LF transmitter arranged on the outside door handle near a driver's seat. The outside door handle indicates a gripping member arranged on the outer surface of the door for opening and closing the door. The first vehicle cabin exterior transmitter 13A is designed such that the response range is within one meter of the outside door handle near the driver's seat. Za in the drawing conceptually represents the response range provided by the first vehicle cabin exterior transmitter 13A. The second vehicle cabin exterior transmitter 13B is an LF transmitter arranged on the outside door handle near a passenger's seat. The second vehicle cabin exterior transmitter 13B is designed such that the area outside the vehicle cabin within one meter of the outside door handle near the passenger's seat is the response range.Zb in the drawing conceptually represents the response range provided by the second vehicle cabin external transmitter 13B.

[0040] The third in-vehicle external transmitter 13C is an LF transmitter arranged on the door handle of a trunk or tailgate. The third in-vehicle external transmitter 13C is designed such that the response range is within a predetermined distance (for example, 0.75 meters) from the trunk outside the vehicle cabin. Zc in the drawing conceptually represents the response range provided by the third in-vehicle external transmitter 13C. A plurality of in-vehicle external transmitters 13 may be built into the door handle, or they may be arranged on a panel near the door handle. Each mode corresponds to the configuration arranged on the door handle. The in-vehicle external transmitter 13 may also be arranged on a part other than the door handle, for example, a B-pillar.The response ranges Za to Zc provided by the respective vehicle cabin external transmitters 13 are located outside the vehicle cabin and do not overlap with the vehicle cabin interior. The response ranges Za to Zc provided by the vehicle cabin external transmitters 13 correspond to a locking range Lx and a second range.

[0041] The size or shape of the response area provided by a single LF transmitter can be appropriately designed. The size of the response area formed by each LF transmitter can be adjusted according to, for example, the response threshold, a transmission power of the LF signal, or a reception sensitivity of the smart key 2. Each vehicle cabin exterior transmitter 13 can provide a response area within 5 meters of the vehicle Hv. The number or arrangement of the LF transmitters included in the on-vehicle system 1 can be appropriately modified. The on-vehicle system 1 can include an LF signal that provides a response area within the trunk.

[0042] A plurality of LF transmitters, such as the in-vehicle cabin transmitter 12 and the out-of-vehicle cabin transmitter 13, may use one antenna for transmitting a predetermined frequency belonging to the LF band. The operating frequency of the LF transmitter can be appropriately designed and may be set to 134 kHz or 30 kHz or less (for example, 28 kHz).

[0043] The receiver 14 is a communication module for receiving a signal from the smart key 2. Specifically, according to the present embodiment, the receiver 14 receives a radio wave having the predetermined frequency (in this example, 315 MHz) belonging to the UHF band. The receiver 14 may use, for example, an antenna for receiving a wireless signal in the UHF band transmitted from the smart key 2 or a demodulation circuit. The frequency for the reception destination of the receiver 14 may be set to a frequency determined in advance as a frequency used for wireless communication with the smart key 2. The frequency used for wireless communication with the smart key 2 may be 920 MHz, 2.4 GHz, or the like.The receiver 21 subjects the signal received by the UHF antenna to predetermined processing such as analog-to-digital conversion, demodulation, and decoding to extract data contained in the received signal. The extracted data is provided to the authentication ECU 11. The receiver 14 may be incorporated into the authentication ECU 11.

[0044] The lock button 15 is a button for the user to issue an instruction to the on-vehicle system 1 to lock the door of the vehicle Hv. When the user presses the lock button 15, the lock button 15 outputs a control signal indicating this fact to the authentication ECU 11. The lock button 15 is arranged at a predetermined position on the outer surface of the door of the vehicle Hv. Even if Fig. 3 illustrates only one locking button 15, the on-board system 1 may include multiple locking buttons. According to an example described here, the locking button 15 is arranged near the exterior door handle of the driver's seat of the vehicle Hv, the exterior door handle of the passenger seat of the vehicle Hv, and the door handle of the trunk lid.

[0045] A touch sensor may be used as a configuration for receiving the door lock instruction from the user. The touch sensor is a device that detects that the user touches the door handle. The touch sensor for receiving the door lock instruction from the user may also be arranged on the outside door handle of the driver's seat door or the passenger's seat door. The configuration for receiving the door lock instruction from the user may include a combination of the lock button 15 and the touch sensor. The lock button 15 or the touch sensor arranged on the door handle may be an input device for the user to output an instruction to open the door of the vehicle Hv.

[0046] The body ECU 16 is an ECU that controls various actuators mounted on the vehicle. For example, the body ECU 16 outputs a predetermined control signal to a door lock motor disposed on each door based on a request from the authentication ECU 11 to lock the respective door. The door lock motor is an electric motor for controlling the state of the lock mechanism as a mechanism for locking the door. The door lock motor and the lock mechanism are disposed on each door. Furthermore, the body ECU 16 acquires information indicating an opening and closing state of the respective doors disposed in the vehicle, information indicating a locking state of the respective doors, and the like. The opening and closing states of the doors can be detected by safety switches.The function of the body ECU 16 may be provided by the authentication ECU 11. In other words, the body ECU 16 may be integrated with the authentication ECU 11. Function of the authentication ECU 11

[0047] The authentication ECU 11, which is in Fig. 5 includes a vehicle information acquisition device F1, a lock instruction determination device F2, a vehicle cabin interior determination device F3, a vehicle cabin exterior determination device F4, and a control execution device F5 as functional blocks for the CPU for executing the above-mentioned authentication device program. Some or all of the functions of the authentication ECU 11 may be implemented in hardware. A configuration in which a certain function is implemented in hardware includes a configuration in which the function is implemented using one or more ICs or the like.

[0048] The vehicle information acquisition device F1 acquires various information (in other words, vehicle information) of the vehicle Hv from a sensor or ECUs mounted on the vehicle. The vehicle information includes, for example, a door opening and closing state, a locking state of each door, whether the lock button 15 is pressed, and the like. The door opening and closing states, the locking state of the doors, and the like can be acquired from, for example, the body ECU 16. Whether the lock button 15 is pressed can be determined from the signal output from the lock button 15.

[0049] Acquiring information indicating the locking state of each door corresponds to determining the locking state of each door. Acquiring information indicating the locking and unlocking states of each door corresponds to determining the locking and unlocking states of each door and detecting the user's opening or closing operation of the door. Acquiring an electrical signal from the lock button corresponds to detecting the user's operation of the lock button. The vehicle information acquisition device F1 corresponds to a configuration for detecting the user's operation of the vehicle Hv, such as opening or closing the door or pressing the lock button 15. The vehicle information mentioned here includes the user's operation of the vehicle Hv.

[0050] The type of information included in the vehicle information is not limited to the information described above. The vehicle information also includes, for example, a shift position detected by a shift position sensor (not shown), a detection result of a brake sensor for detecting whether a brake pedal is depressed, and the state of a vehicle power source. The operating state of the parking brake may also be included in the vehicle information.

[0051] Furthermore, the vehicle information acquisition device F1 determines a current state of the vehicle Hv based on the various information described above. For example, when the vehicle information acquisition device F1 determines that a driving power supply (e.g., an ignition power supply) is turned off and all the doors are locked, the vehicle information acquisition device F1 determines that the vehicle Hv is parked. Needless to say, the condition for determining that the vehicle Hv is parked can be appropriately designed, and various determination conditions can be used. The vehicle information acquisition device F1 detects that all the doors are closed based on the information indicating each door opening and closing state. Therefore, the vehicle information acquisition device F1 corresponds to a door closing detector.

[0052] The lock instruction determining device F2 determines whether the user issues an instruction to lock the door. The lock instruction determining device F2 according to the present embodiment determines whether the user issues an instruction to lock the vehicle door based on an output signal of the lock knob 15. Specifically, the lock instruction determining device F2 determines that the user issues an instruction to lock the vehicle door Hv when the lock knob 15 outputs a signal indicating that the knob is pressed by the user in a state where the vehicle door is not locked.

[0053] The locking instruction determining device F2 may receive the door locking instruction by means of a voice command. For example, the locking instruction determining device F2 may receive an instruction to execute the door locking by performing a voice recognition process on a user's voice signal acquired by a microphone for collecting sound outside the vehicle cabin. The microphone for obtaining the voice command corresponding to the instruction to execute the door locking may be arranged on the outer surface of the vehicle Hv, such as an outer portion of the B-pillar of the vehicle Hv.

[0054] The locking instruction determining device F2 can receive an instruction to perform a door lock based on an output signal from an infrared sensor providing a detection range below the door. Specifically, the locking instruction determining device F2 can determine that the user issues an instruction to lock the door when the locking instruction determining device F2 receives a signal from the infrared sensor indicating that the user is placing their foot above the detection range. According to such a configuration, the user can issue an instruction to lock the door by placing their foot below the door. The lock button 15, the microphone arranged on the outer surface of the vehicle Hv, the infrared sensor providing a detection range below the door, or the like correspond to an input device for the user to input an instruction to lock the door.

[0055] The vehicle cabin interior determination device F3 determines whether the smart key 2 is present inside the vehicle cabin based on the communication state with the smart key 2 using the vehicle cabin interior transmitter 12. The vehicle cabin interior determination device F3 generally transmits a response request signal toward the vehicle interior in collaboration with the vehicle cabin interior transmitter 12, and determines whether the smart key 2 is present inside the vehicle cabin based on whether the vehicle cabin interior determination device F3 receives a response signal corresponding to the response request signal. The response request signal is an LF signal for requesting the smart key 2 to return the response signal.

[0056] The vehicle cabin exterior determination device F4 determines whether the smart key 2 is present in the lock area Lx based on the communication state with the smart key 2 by using the vehicle cabin exterior transmitter 13. The vehicle cabin exterior determination device F4 generally transmits the response request signal toward the vehicle cabin exterior in collaboration with each vehicle cabin exterior transmitter 13, and determines whether the smart key 2 is present in the lock area Lx based on whether the vehicle cabin exterior determination device F4 receives a response signal corresponding to the response request signal. In other words, the lock area Lx is the response area provided by the vehicle cabin exterior transmitter 13.

[0057] The details of the vehicle cabin interior determination device F3 and the vehicle cabin exterior determination device F4 are described below. The vehicle cabin interior determination device F3 corresponds to a first area determination device. The vehicle cabin exterior determination device F4 corresponds to a second area determination device. Whether the response signal is received or not corresponds to the reception state. The configuration including the vehicle cabin interior transmitter 12 and the receiver 14 corresponds to the vehicle cabin interior communication device and a first communication device. The configuration including the vehicle cabin exterior transmitter 13 and the receiver 14 corresponds to the vehicle cabin exterior communication device and the second communication device.

[0058] The vehicle cabin exterior communication device F4 includes an authentication processor F41 as a more detailed functional block. The authentication processor F41 performs the authentication process via wireless communication with the smart key 2 using a challenge code. The challenge code is a code for authenticating the smart key 2. The challenge code may be a random number generated using a random number table or the like. For example, the authentication processor F41 generates the challenge code in response to receiving the simplified response signal described later.

[0059] The vehicle cabin exterior determination device F4 transmits the response request signal containing the challenge code generated by the authentication processor F41 at a predetermined time, such as when the simplified response signal is received. As described above, the smart key 2 returns an RF signal (so-called response signal) containing the response code with the challenge code encrypted by the encryption key registered in advance in the smart key in response to receiving the signal containing the challenge code.

[0060] The authentication processor F41 generates a verification code for each smart key 2 by using the encryption key for each smart key in response to the generation of the challenge code. The verification code is a code obtained by encrypting the challenge code using the encryption key of the smart key 2. The authentication processor F41 determines that the authorized smart key 2 is the communication target (in other words, successful authentication) in response to the response code returned from the smart key 2 that matches the verification code. The vehicle cabin interior determination device F3 may include a function corresponding to the above-mentioned authentication processor F41.

[0061] The control execution device F5 executes vehicle control such as door locking or unlocking in collaboration with the body ECU 16. For example, the control execution device F5 requests the body ECU 16 to lock the door of the vehicle Hv when: the vehicle cabin interior determination device F3 determines that none of the smart keys is present inside the vehicle cabin; and the vehicle cabin exterior determination device F4 determines that at least one of the smart keys 2 is present in the lock area Lx. As described above, the body ECU 16 locks each door by driving the door lock motor based on the request from the authentication ECU 11. Door locking process

[0062] The following describes the door locking process executed by the authentication ECU 11 with reference to the flowchart of Fig. 6. The flowchart shown in Fig. 6, may be started in a situation where the locking instruction determining device F2 determines that the user issues an instruction to lock the door. Specifically, the flowchart may start in response to pressing the lock button 15 when the door of the vehicle Hv has not been locked. The door locking process includes steps S1 to S5.

[0063] In step S1, the vehicle cabin exterior determination device F4 executes a vehicle cabin exterior presence confirmation process in collaboration with the vehicle cabin exterior transmitter 13 and the receiver 14, respectively. The vehicle cabin exterior presence confirmation process is a process that determines whether the smart key is present in the lock area Lx. The vehicle cabin exterior presence confirmation process will be described in more detail below with reference to Fig. 7 described.

[0064] In a situation where, as a result of the vehicle cabin outside presence confirmation process in step S1, it is determined that at least one of the smart keys 2 registered in the vehicle Hv is present in the lock area Lx, the determination result in step S2 is affirmative, and then step S3 is executed. On the other hand, in a situation where, as a result of the vehicle cabin outside presence confirmation process in step S1, none of the smart keys 2 is present in the lock area Lx, the determination result in step S2 is negative, and then the current flow is terminated. In a situation where the process is terminated due to no smart key 2 being found within the lock area Lx, the on-vehicle display may display a message or inform the user that no smart key 2 has been found.The information for the user can be provided by emitting an alarm tone with a predetermined pattern or by switching on a light (for example a headlight or a warning light) mounted on the vehicle.

[0065] In step S3, the vehicle cabin interior determination device F3 executes a vehicle cabin interior absence confirmation process in collaboration with the vehicle cabin interior transmitter 12 and the receiver 14. The vehicle cabin interior absence confirmation process is a process that determines whether the smart key 2 is present inside the vehicle cabin. The vehicle cabin interior absence confirmation process will be described below with reference to Fig. 9 in detail. In a situation where, as a result of the vehicle cabin interior absence confirmation process in step S3, it is determined that none of the smart keys 2 is present inside the vehicle cabin, the determination result in step S4 is negative, and then step S5 is executed. On the other hand, in a situation where, as a result of the vehicle cabin interior absence confirmation process in step S3, it is determined that a smart key 2 is present inside the vehicle cabin, the determination result in step S4 is positive, and then the current flow is terminated. In a situation where the process is terminated due to the smart key 2 remaining inside the vehicle cabin, the on-vehicle display may, for example, display a message to inform the user that the smart key 2 remains inside the vehicle cabin.The notification to the user that the smart key 2 remains or has remained within the vehicle cabin may be made by emitting an alarm sound with a predetermined pattern or turning on a light (for example, a headlight or a warning light) mounted on the vehicle.

[0066] In step S5, the control execution device F5 requests the body ECU 111 to lock the door of the vehicle Hv. The body ECU 111 drives the door lock motor based on the request from the authentication ECU 11 and sets the locking mechanism of each door to the locked state. When the process in step S5 is completed, the current flow ends. Vehicle cabin exterior presence confirmation process

[0067] The following describes the vehicle cabin outside presence confirmation process executed by the vehicle cabin outside determination device F4 with reference to the flowchart of Fig. 7. The vehicle cabin exterior presence confirmation process is executed, for example, as step S1 of the door locking process. The vehicle cabin exterior presence confirmation process of the present embodiment includes, for example, steps S101 to S112. Each step is executed in collaboration with the vehicle cabin exterior transmitter 13 or the receiver 14, as needed.

[0068] In step S101, a time difference response request signal is transmitted from each vehicle cabin exterior transmitter 13. The time difference response request signal is an LF signal that requests each smart key 2 to return the response signal at a timing that does not overlap with other timings. The time difference response request signal corresponds to an example of the response request signal. The timing at which each smart key 2 returns the response signal corresponding to the time difference response request signal can be registered in advance in the smart key 2.

[0069] The smart key 2 is designed, for example, such that the smart keys 2a, 2b and 2c each transmit the response signals in chronological order with a time difference as in Fig. 8. Specifically, the smart key 2a returns the response signal in a first time period after a time point at which the time difference response request signal is received and is defined as a start time. The smart key 2b returns the response signal in the second time period as a time period subsequent to the first time period. The smart key 2c returns the response signal in the third time period as a time period subsequent to the second time period.

[0070] Each time period corresponds to a time period during which the smart key 2 transmits the response signal, in other words, a time period during which the authentication ECU 111 waits for the return of the response signal from the smart key 2. Each time period is set to a length required for the smart key 2 to complete the return of the response signal. Fig. 8 conceptually illustrates the behavior of each device in a situation where the smart keys 2b and 2c are present in the lock area Lx when the vehicle cabin outside presence confirmation process is executed.

[0071] Although it is described here that the timing for requesting each smart key 2 to return the response signal to a time difference response request signal is registered in advance, the execution method for each smart key 2 to respond to a response request signal with a time difference is not limited to this situation. For example, the time difference response request signal may include data that determines the timing for each smart key to return the response signal. This data is referred to as return timing determination data. In a situation where the time difference response request signal includes the return timing determination data, each smart key 2 can return the response signal at a timing determined by the return timing determination data.The return timing determination data determines a delay time from the receipt of the time difference response request signal by each smart key 2 for returning the response signal. The timing is uniquely determined for each smart key 2. Furthermore, each smart key 2 can arbitrate or select the transmission timing of the response signal using CSMA / CA (Carrier-Aware Multiple Access / Collision Avoidance).

[0072] The time difference response request signal transmitted in step S101 is the response request signal for all smart keys 2. In step S101, the time difference response request signal includes a challenge code, for example, and is an LF signal configured to request the return of a response code. Therefore, each smart key 2 that has received the time difference response request signal returns a signal containing the response code corresponding to the challenge code included in the time difference response request signal as a response signal.

[0073] According to another aspect, the time difference response request signal transmitted in step S101 may request the return of a response signal (hereinafter referred to as a simplified response signal) indicating a constant bit string registered in advance in the smart key 2. The simplified response signal corresponds to a signal that does not include the response code. The simplified response signal may include source information so that the authentication ECU 11 can identify which smart key responded. The source information may be the key ID or a key number indicating the smart key number.In a situation where the time difference response request signal requests the return of the simplified response signal, the authentication ECU 11 may separately transmit the response request signal containing the challenge code to the smart key 2 that returned the simplified response signal when the authentication ECU 11 receives the response signal from the smart key 2. When the transmission of the time difference response request signal is completed, the process proceeds to step S102. When the transmission of the time difference response request signal is completed, the authentication ECU 11 starts measuring the elapsed time since the transmission was completed. The authentication processor F41 calculates the verification code for each smart key 2 according to the challenge code included in the time difference response request signal transmitted in step S101.

[0074] In step S102, it is determined whether the response signal is received from one (the smart key 2a in this example) of the smart keys 2 that should return the response signal in the first period. In a situation where the response signal from the smart key 2a is received in the first period, the determination result in step S102 is affirmative, and then step S103 is executed. On the other hand, in a situation where the response signal from the smart key 2a cannot be received in the first period, the determination result in step S102 is negative, and then step S107 is executed.

[0075] In step S103, the authentication processor F41 performs verification of the response code included in the received response signal. In a situation where the received response code matches the verification code as a result of the verification process in step S103 (in other words, Yes in step S104), step S105 is executed. On the other hand, in a situation where the received response code does not match the verification code as a result of the verification process in step S103 (in other words, No in step S104), the process proceeds to step S106.

[0076] In step S105, it is determined that the smart key 2a is present in the lock area Lx, and then the process proceeds to step S108. In step S106, a predetermined authentication failure process is executed, and then the process proceeds to step S108. The authentication failure process is a process to be executed when the authentication of the smart key fails, and the specific content of the authentication failure process can be appropriately designed. For example, the authentication failure process may resend the challenge code and retry the authentication of the smart key 2a. In the authentication failure process, the smart key 2a may be considered not to be present. In step S107, it is determined that the smart key 2a is not present in the lock area Lx, and then the process proceeds to step S108.

[0077] In step S108, it is determined whether a total waiting time has elapsed after transmission of the time difference response request signal. The total waiting time is set to a value obtained by adding a predetermined margin to the sum value of the times from the first period to the third period. In a situation where the total waiting time has not elapsed after transmission of the time difference response request signal, the determination result in step S108 is negative, and then the process proceeds to step S102, and the response of the response signal from another smart key 2 is waited for.

[0078] For example, when the first period ends, the determination result in step S108 is negative, and then the process returns to step S102, and then waits for the response of the response signal from the smart key 2b. In other words, it is determined whether the smart key 2b is present in the lock area Lx. When the second period ends, the determination result in step S108 is negative, and the process returns to step S102, and waits for the response of the response signal from the smart key 2c. In other words, it is determined whether the smart key 2c is present in the lock area Lx. The subsequent process from step S102 to step S108 corresponds to a process of waiting for the response from each smart key 2.In a situation where the total waiting time has elapsed since the transmission of the time difference response request signal in step S108, the process proceeds to step S109.

[0079] In step S109, the process subsequent to steps S101 to S108 determines whether at least one of the smart keys 2 is present in the lock area Lx. In a situation where it is determined that at least one of the smart keys 2 is present in the lock area Lx, the determination result in step S109 is affirmative, and then the process proceeds to step S110. On the other hand, in a situation where none of the smart keys is detected, the determination result in step S109 is negative, and then the process proceeds to step S111.

[0080] In step S110, a vehicle cabin outside presence flag is set to an on state, and the current flow ends. In step S111, the vehicle cabin outside presence flag is set to an off state (reset), and then step S112 is executed. The vehicle cabin outside presence flag is a flag in the process that indicates whether the smart key 2 is present in the lock area Lx. The situation in which the vehicle cabin outside presence flag is in the on state indicates that the smart key 2 is present in the lock area Lx. The situation in which the vehicle cabin outside presence flag is in the off state indicates that the smart key 2 is not present in the lock area Lx. Step S2 in the door locking process of the Fig. 6 can be determined based on the setting state of the vehicle cabin exterior presence flag.

[0081] In step S112, a detection error handling process is executed, and then the current flow ends. The detection error processing may be a process to be executed in a situation where it cannot be confirmed that the smart key 2 is present in the lock area Lx, and the specific content of the detection error processing may be appropriately designed. For example, the detection error processing may be a process for re-executing the process subsequent to step S101. In the detection error processing, the user may be notified by, for example, emitting an alarm sound, displaying a message on the in-vehicle display, or turning on or off an in-vehicle lamp. Vehicle cabin interior absence confirmation process

[0082] The following describes the vehicle cabin outside presence confirmation process executed by the vehicle cabin outside determination device F4 with reference to the flowchart of Fig. 9. The vehicle cabin interior absence confirmation process is executed, for example, as step S3 of the above-mentioned door locking process. In the present embodiment, the vehicle cabin interior absence confirmation process includes, for example, steps S201 to S212.

[0083] In step S201, a vehicle cabin presence flag is set to the off state, and then the process proceeds to step S202. The vehicle cabin presence flag in the process is a flag indicating whether the smart key 2 is present inside the vehicle cabin. The situation in which the vehicle cabin presence flag is in the on state indicates that the smart key 2 is present inside the vehicle cabin. The situation in which the vehicle cabin presence flag is in the off state indicates that the smart key 2 is not present inside the vehicle cabin. The initial value of the vehicle cabin presence flag may be the on state.

[0084] In step S202, the in-vehicle transmitter 12 transmits the simultaneous response request signal. The simultaneous response request signal is a response request signal that requests each smart key 2 to return the response signal immediately (ie, simultaneously) after each smart key 2 receives the simultaneous response request signal. In the present embodiment, for example, the simultaneous response request signal is a response request signal that requests all smart keys 2 to respond. In other words, all smart keys 2 are targets.

[0085] The simultaneous response request signal is a signal requesting the smart key 2 to return the simplified response signal. In other words, the simultaneous response request signal does not contain the challenge code. The transmission of the simultaneous response request signal is terminated, and then the process proceeds to step S203. When the transmission of the simultaneous response request signal is terminated, the authentication ECU 11 starts measuring the elapsed time since the transmission was terminated.

[0086] In step S203, it is determined whether the response signal from the smart key 2 has been received. In a situation where the response signal from the smart key 2 has been received, step S204 is executed. That is, the vehicle cabin presence flag is set to the on state, and then the process proceeds to step S210. On the other hand, in a situation where the response signal has not been received after the predetermined waiting time has elapsed since the simultaneous response request signal was transmitted, the determination result in step S203 is negative, and then step S205 is executed.

[0087] In step S205, it is determined whether a quasi-signal has been received in a period (in other words, during a response waiting state) from the transmission of the simultaneous response request signal until the elapse of the response waiting time. Here, the quasi-signal is a radio wave with a signal strength similar to that of the response signal. For example, it is determined that the quasi-signal has been received when noise (actually, the radio wave) having a signal strength equal to or greater than a predetermined threshold is received. Here, the noise is a radio wave that does not have a signal pattern corresponding to the response signal. According to another aspect, a received signal that cannot be demodulated corresponds to the noise.The quasi-signal is a signal that presumes an observed radio wave when the response signals transmitted simultaneously by multiple smart keys 2 collide with each other or an external signal is superimposed on the response signal.

[0088] In a situation where the quasi-signal was received while waiting for a response, the determination result in step S205 is affirmative, and then step S206 is executed. On the other hand, if no quasi-signal was received, the determination result in step S205 is negative, and step S208 is executed. In step S206, an individual confirmation process is executed. The individual confirmation process performs wireless communication with the smart keys 2 individually at a timing that does not overlap with other timings for determining whether the smart keys 2 are present.

[0089] The vehicle cabin interior determination device F3 of the present embodiment determines whether the smart key is present inside the vehicle cabin by transmitting the time difference response request signal to all the smart keys 2 via the vehicle cabin interior transmitter 12. The method for determining whether the smart key 2 is present inside the vehicle cabin by using the time difference response request signal may use a similar method to the vehicle cabin exterior determination process described above. That is, it is determined that at least one of the smart keys 2 is present inside the vehicle cabin when the response signal is received from the at least one smart key 2 after transmitting the time difference response request signal.It is determined that no smart key 2 is present inside the vehicle cabin when the response signal is not received from any of the smart keys 2 after the time difference response request signal is transmitted.

[0090] In a situation where the presence of at least one of the smart keys 2 has been confirmed by the transmission of the time difference response request signal as a result of the individual confirmation process (in other words, Yes in step S207), the vehicle cabin interior presence flag is set to the on state, and then the process proceeds to step S210. In a situation where the response signal has not been received from any smart key 2 after the transmission of the time difference response request signal, the process proceeds to step S208.

[0091] In step S208, it is provisionally determined that no smart key 2 is present inside the vehicle cabin, and then the process proceeds to step S209. Step S208 corresponds to a process that maintains a state in which the vehicle cabin inside presence flag is set to the off state.

[0092] In step S209, it is determined whether the occurrence frequency of a provisional determination that the smart key 2 is not present inside the vehicle cabin has reached a predetermined confirmation occurrence frequency. The confirmation occurrence frequency is, for example, 3. The specific confirmation occurrence frequency can be appropriately set to, for example, 2 or 4. The confirmation occurrence frequency can be set to 2 or more assuming that the response signal was not received due to a communication error. However, the confirmation occurrence frequency can also be set to 1.

[0093] In a situation where the frequency of provisional determination that no smart key 2 is present inside the vehicle cabin has reached the confirmation occurrence frequency, the process proceeds to step S210. On the other hand, in a situation where the frequency of provisional determination that no smart key is present inside the vehicle cabin has not reached the confirmation occurrence frequency, the determination result in step S209 is negative, and the process from step S202 is executed.

[0094] In step S210, it is determined whether the vehicle cabin interior presence flag is set to the off state. In a situation where the vehicle cabin interior presence flag is in the off state (in other words, Yes in step S210), the determination result that no smart key 2 is present inside the vehicle cabin is confirmed, and then the process ends (in other words, step S211). On the other hand, in a situation where the vehicle cabin interior presence flag is in the on state (in other words, No in step S210), it is determined that the smart key 2 remains or is present inside the vehicle cabin, and then the current flow ends (in other words, step S212).

[0095] Fig. 10 conceptually illustrates the operation of the vehicle cabin interior absence confirmation process in a situation where none of the smart keys 2 is present inside the vehicle cabin. In a situation where the smart key 2 is not present, none of the smart keys 2 returns the response signal (in this example, the simplified response signal) to the simultaneous response request signal transmitted in step S202. Since a collision of the response signal does not occur, no quasi-signal can be observed. Therefore, the determination result in steps S203 and S205 is negative, and then, in step S208, it is provisionally determined that no smart key is present inside the vehicle cabin. The subsequent process is executed three times to confirm the determination that the smart key 2 is not present inside the vehicle cabin.

[0096] Fig. 11 conceptually illustrates the operation of the vehicle cabin interior absence confirmation process in a situation where one of the smart keys 2 (in this example, the smart key 2c) remains or is present inside the vehicle cabin. In a situation where the smart key 2c remains inside the vehicle cabin, the authentication ECU 11 receives the response signal from the smart key 2c (in other words, Yes in step S203) because the smart key 2c returns the response signal (in this example, the simplified response signal) to the simultaneous response request signal transmitted in step S202. As a result, it is determined that the smart key 2 is present inside the vehicle cabin. Since the other smart keys 2 do not return a response signal, no collision of the response signals occurs, and the response signal from the smart key 2c is normally received by the receiver 14.

[0097] Fig. 12 conceptually illustrates the operation of the vehicle cabin interior absence confirmation process in a situation where two of the smart keys (for example, the smart keys 2b, 2c) remain inside the vehicle cabin. In a situation where the smart keys 2b, 2c remain inside the vehicle cabin, the smart keys 2b, 2c return a response signal (in this example, the simplified response signal) to the simultaneous response request signal transmitted in step S202. Since the time difference at which the smart keys 2b, 2c respectively return the response signals is not fixed, these response signals may cause a collision (in other words, interference), and demodulation in the receiver 14 may fail.

[0098] However, the signal in which the response signals of the respective smart keys 2b, 2c overlap has a signal strength similar to that of the response signal. Therefore, the respective response signals of the smart keys 2b, 2c are observed as quasi-signals (in other words, Yes in step S205), and the individual confirmation process is executed (in other words, step S206). The individual confirmation process performs wireless communication with the smart keys 2 individually at a time that does not overlap with other times to determine whether the smart key 2 is present without communication interference. As a result, in the example shown in Fig. 12, detects that the smart keys 2b, 2c are present inside the vehicle cabin. In other words, even if multiple smart keys 2 are present inside the vehicle cabin, it is possible to determine whether the smart key 2 remains inside the vehicle cabin and reduce the possibility of the smart key 2 being locked inside the vehicle cabin. Effects of the embodiment

[0099] The following section describes the effects of the above embodiment by introducing a comparison configuration.

[0100] As it is in Fig. 13, the comparison configuration confirms that no smart key 2 is present inside the vehicle cabin by transmitting the time difference response request signal a plurality of times. In such a comparison configuration, the total waiting time for one transmission of the time difference response request signal is longer as the number of smart keys 2 is larger. Therefore, it is necessary to wait for the response from each smart key 2 with a time difference. For example, in a situation where six smart keys 2 are issued for the vehicle Hv, it is necessary to wait six time periods. Thus, with respect to the comparison configuration, the time Tc required to confirm the determination that no smart key is present inside the vehicle cabin is longer with respect to the number of smart keys 2 present in the vehicle Hv.

[0101] On the other hand, the configuration of the present embodiment requests each smart key 2 to respond simultaneously. In other words, the authentication ECU 11 of the present embodiment receives the response from each of the smart keys 2 without any time difference. Subsequently, based on the situation where no response signal is received from the smart keys 2, it is determined that no smart key 2 is present inside the vehicle cabin.

[0102] According to the configuration, in a situation where no smart key 2 is present inside the vehicle cabin, the time Tp (hereinafter referred to as absence determination required time) required to confirm the determination that no smart key 2 is present inside the vehicle cabin is independent of the number of smart keys 2. In other words, the response waiting time associated with transmission of the simultaneous response request signal is constant independent of the number of smart keys 2. Even if the number of smart keys 2 of the vehicle Hv increases, the absence determination required time does not change in a situation where no smart key 2 is present inside the vehicle cabin. Therefore, it is possible to prevent an increase in the absence determination required time Tp as the number of smart keys 2 of the vehicle Hv increases.

[0103] According to the above configuration, since the response from each smart key 2 is awaited without a time difference, it is possible to minimize the time required for provisionally determining that no smart key 2 is present inside the vehicle cabin. Along with this situation, it is possible to minimize the absence determination required time Tp in a situation where no smart key 2 is present inside the vehicle cabin. Accordingly, it is possible to improve the responsiveness to a user's locking operation in a situation where no smart key 2 is present inside the vehicle cabin. The effect of reducing the absence determination required time Tp of the present embodiment compared to the comparative configuration is remarkable when the number of issued smart keys 2 is larger.

[0104] In the above configuration, regarding the determination of whether the smart key 2 is present within the lock area Lx, detection of the smart key 2 is attempted by using the time difference response challenge signal instead of the simultaneous response challenge signal. Furthermore, in the vehicle cabin exterior confirmation process, the authentication process of the smart key 2 that returned the response signal is executed. Therefore, it is possible to improve the certainty of the determination result that the smart key 2 is present within the lock area Lx. According to the configuration in which the response challenge signal containing the challenge code is transmitted as the time difference response challenge signal, it is possible to shorten the time required to determine that the smart key 2 is present within the lock area Lx.

[0105] As described above, the authentication ECU 11 of the present embodiment detects that the smart key 2 is present outside the vehicle cabin by performing wireless communication with the respective smart keys 2 at non-overlapping timings. The situation where no smart key 2 is present inside the vehicle cabin is confirmed based on the condition that no radio wave corresponding to the response signal has been received. Such a configuration corresponds to a configuration that separately provides a detector for detecting that the smart key 2 is present in the lock area Lx and a detector for detecting that no smart key 2 is present inside the vehicle cabin.

[0106] While the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications described below are included in the technical scope of the present invention, and the present invention can be implemented by various modifications within the scope of the invention. For example, various modifications described below can be appropriately implemented in combination if there is no technical inconsistency. Note that elements having the same functions as in the above-described embodiment are denoted by the same reference numerals, and the description of these elements will not be repeated. When only a part of the configuration is described, the configuration of the above-described embodiment can be referred to with respect to the other parts. First modification

[0107] In the above-described embodiment, it is described that, in step S202, the vehicle cabin interior determination device F3 transmits the LF signal as the simultaneous response request signal to request all the smart keys 2 to return the response signal simultaneously. However, this situation is not limited to this. The simultaneous response request signal transmitted in step S202 may be an LF signal for requesting only a portion of the smart keys 2 to return the response signal. Specific examples will be described below.

[0108] According to the procedure of the door locking process in the above-described embodiment, the vehicle cabin inside absence confirmation process is executed under the condition that the vehicle cabin outside presence confirmation process is executed to confirm the presence of at least one smart key 2 in the lock area Lx. In other words, at this stage of executing the vehicle cabin outside presence confirmation process, it has been identified that at least one of the smart keys 2 is present in the lock area Lx. Regarding the smart key 2 identified as being present outside the vehicle cabin, it is not necessary to request the return of the response signal in the vehicle cabin inside absence confirmation process.

[0109] In view of such circumstances, the simultaneous response request signal transmitted in step S202 of the vehicle cabin inside absence confirmation process may also be an LF signal for requesting only the smart key 2, whose location has not been confirmed by the vehicle cabin outside presence confirmation process, to return the response signal. For example, as shown in Fig. As shown in Fig. 14, in a situation where the vehicle cabin exterior presence confirmation process determines that the smart key 2c is present in the lock area Lx, the vehicle cabin interior determination device F3 transmits the simultaneous response request signal to the smart keys 2a, 2b as in step S202. The response request signal for the target smart key 2 is an LF signal that requests the smart key 2 to return the response signal.

[0110] For simplicity, the smart key 2 that has been confirmed as being present in the lock area Lx by the vehicle cabin outside presence confirmation process may be referred to as a detected key. A smart key 2 other than the detected key may also be referred to as an unrecognized key. The unrecognized key corresponds to the smart key 2 whose location is unknown at the time the vehicle cabin outside presence confirmation process is completed. In the example shown in Fig. As shown in Figure 14, the smart keys 2a, 2b correspond to unacquired keys at the time the vehicle cabin outside presence confirmation process is completed. The simultaneous response request signal for requesting the unacquired keys to return the response signal simultaneously may also be referred to as a simultaneous response request signal for unacquired keys. The simultaneous response request signal for unacquired keys corresponds to a simultaneous response request signal that prohibits the acquired key from returning a response signal.

[0111] Fig. 14 conceptually illustrates an example of the operation of each device at the time of the vehicle cabin absence determination process in a situation where the smart keys 2a, 2b are not present inside the vehicle cabin. According to another example, in a situation where the smart key 2a remains inside the cabin, the authentication ECU 11 receives the response signal sent from the smart key 2a to the simultaneous response signal for unacquired keys. In a situation where the smart keys 2a, 2b remain inside the vehicle cabin, the authentication ECU 11 executes the individual confirmation process because the authentication ECU 11 receives the quasi-signal.

[0112] Since the detected key is confirmed as being outside the vehicle cabin, it is not necessary for the detected key to return the response signal in the individual confirmation process in step S206, and it is not necessary to wait for the return of the response signal. In other words, the individual confirmation process in step S206 only needs to be performed with respect to the key(s) not detected. As shown in Fig. As shown in Figure 14, in a situation where the smart key 2c is the acquired key, the individual confirmation process can be executed with respect to the smart keys 2a, 2b when the quasi-signal is received. The individual confirmation process for the smart keys 2a, 2b can be executed, for example, by transmitting the time difference response request signal for requesting only the smart keys 2a, 2b as the non-acquired keys to return the response signal. The time difference response request signal for non-acquired keys corresponds to a time difference response request signal that prohibits the acquired key(s) from returning the response signal.

[0113] According to the above configuration, since the number of smart keys 2 requested to return the response signals simultaneously by the simultaneous response request signal is limited, it is possible to reduce a possibility of collision of the response signals of the respective smart keys 2. In a situation where the response range of the in-vehicle cabin transmitter 12 leaks to the outside of the vehicle cabin, it is possible to reduce the possibility of the smart key 2 existing outside the vehicle cabin returning the response signal to the simultaneous response request signal transmitted from the in-vehicle cabin transmitter 12. In other words, in a situation where the response range of the in-vehicle cabin transmitter 12 leaks to the outside of the vehicle cabin,is sufficient, it is possible to reduce the probability of erroneously determining that the smart key 2 remains inside the vehicle cabin when the smart key 2 is actually outside the vehicle cabin.

[0114] The vehicle cabin inside determination device F3 can determine that no smart key 2 is present inside the vehicle cabin when the vehicle cabin outside presence confirmation process has confirmed that all smart keys 2 are present in the lock area Lx. In a situation where the vehicle cabin outside presence confirmation process has confirmed that all smart keys 2 are present in the lock area Lx, the number of confirmations can be modified to a smaller number (for example, one) than usual. Second modification

[0115] In the above-described embodiment or the first modification, it is described that the individual confirmation process (in other words, S202) performs the determination as to whether a respective smart key 2 (in other words, an individual smart key 2) is present inside the vehicle cabin by transmitting the time difference response request signal for all or part of the smart keys 2. However, the method for determining as to a respective individual smart key 2 is not limited to this method. For example, the vehicle cabin interior determination device F3 may determine whether a respective smart key 2 is present inside the vehicle cabin by sequentially transmitting an individual response request signal for requesting only a specific smart key 2 to return the response signal, as shown in Fig. 15 is shown. Fig. 15 illustrates the operation of a respective device in a situation where the smart key 2b is present inside the vehicle cabin.

[0116] The vehicle cabin exterior determination device F4 can also determine whether a respective smart key 2 is present in the lock area by sequentially transmitting the individual response request signal for each smart key 2. Such a configuration corresponds to a configuration for requesting the respective smart keys 2 to return the response signal such that the return timings of the respective response signals of the smart keys 2 do not overlap. Third modification

[0117] In the above-described embodiment, it is described that the vehicle cabin interior absence confirmation process is executed after the vehicle cabin exterior presence confirmation process is executed, which is triggered by pressing the lock button 15. However, it is not limited to this situation. For example, as shown in Fig. 16, the door lock process may execute the vehicle cabin inside absence confirmation process triggered by closing all the doors of the vehicle Hv, and may then execute the vehicle cabin outside presence confirmation process in a situation where the lock button 15 is pressed.

[0118] In the following, the door locking process of the third embodiment will be described with reference to the flowchart of Fig. 16. The flow chart of the Fig.16 may start when the vehicle information acquisition device F1 detects that all the doors of the vehicle Hv are closed. The door locking process of the present modification includes steps S301 to S306.

[0119] In step S301, the vehicle cabin interior determination device F3 executes the vehicle cabin interior absence confirmation process, and then the process proceeds to step S302. Step S302 determines whether a smart key 2 is present inside the vehicle cabin. If, as a result of the vehicle cabin interior absence confirmation process in step S301, it is determined that no smart key 2 is present inside the vehicle cabin, the determination result in step S302 is negative, and then step S303 is executed. On the other hand, if, as a result of the vehicle cabin interior absence confirmation process in step S301, it is determined that a smart key 2 is present inside the vehicle cabin, the determination result in step S302 is positive, and then the process flow ends.

[0120] In step S303, the vehicle information acquisition device F1 determines whether the user presses the lock button. If the user presses the lock button, the determination result in step S303 is affirmative, and then the vehicle cabin exterior presence confirmation process is executed in step S304.

[0121] In step S304, the vehicle cabin exterior presence determination device F4 executes the vehicle cabin exterior presence confirmation process, and then the process proceeds to step S305. Step S305 determines whether the smart key 2 is present in the lock area Lx. In step S305, if it is detected that the smart key 2 is present in the lock area Lx as a result of the vehicle cabin exterior presence confirmation process in step S304, the determination result is affirmative, and then step S306 is executed. On the other hand, if it is detected that the smart key 2 is not present in the lock area as a result of the vehicle cabin exterior presence confirmation process in step S304, the determination result in step S305 is negative, and then the process flow ends.

[0122] In step S306, the control execution device F5 locks the door of the vehicle Hv in collaboration with the body ECU 16, and then the current flow ends. According to the above configuration, it is possible to improve the responsiveness to the user's locking instruction. Additional Remarks: Authentication ECU Configuration 11

[0123] Some or all of the functions of the authentication ECU 11 may be implemented in hardware. A configuration in which a specific function is implemented in hardware includes a configuration in which the function is implemented using one or more ICs or the like. The units or functions provided by the authentication ECU 11 may be implemented by software stored in a tangible storage device and a computer executing the software, by software only, by hardware only, or by a combination of the software and hardware. For example, when the authentication ECU 11 is implemented by an electronic circuit as hardware, it is possible to implement it by a digital circuit including multiple logic circuits or analog circuits.

[0124] The authentication ECU 11 may also be provided by a set of computing resources connected via a data communication device. Part of the functions provided by the authentication ECU 11 of the present embodiment may be included in another ECU (for example, the body ECU). In a situation where the functions provided by the authentication ECU 11 are distributed among multiple ECUs, the configuration including these ECUs corresponds to the vehicle authentication device.

[0125] The process of the flowchart or flowchart described in this application contains multiple sections (or steps), each section being designated, for example, S1. Each section can be divided into multiple subsections, while multiple sections can also be combined into a single section. Furthermore, each section thus configured can also be referred to as a device, module, or facility.

Claims

[1] A vehicle authentication device including a plurality of mobile devices each serving as a key of a vehicle, the vehicle authentication device comprising: a first communication device (12) configured to determine a first area set in advance for the vehicle as a communication area; a second communication device (13) configured to determine a second area, which is set in advance for the vehicle and does not overlap with the first area, as the communication area; a first area determining device (F3) configured to determine whether the mobile devices are present in the first area based on a communication state between the first communication device and the mobile devices; a second area determining device (F4) configured to determine whether the mobile devices are present in the second area based on a communication state between the second communication device and the mobile devices; a control execution device (F5) configured to execute a predetermined vehicle control in response to the first area determining device determines that none of the mobile devices is present in the first area; and the second area determining device determines that at least one of the mobile devices is present in the second area, wherein the first area determining device is further designed transmit a simultaneous response request signal for simultaneously requesting the mobile devices to return respective response signals in collaboration with the first communication device; and in response to the first area determining device not receiving the response signals corresponding to the simultaneous response request signal originating from the mobile devices, respectively, to determine that the mobile devices are not present in the first area, and wherein the second area determining device is further designed requesting the mobile devices in collaboration with the second communication device to return the response signals at different return times that do not overlap; and in response to the second area determining device receiving at least one of the response signals originating from the mobile devices, respectively, to determine that the at least one of the mobile devices is present in the second area. [2] The vehicle authentication device according to claim 1, further comprising: a vehicle cabin interior communication device configured as the first communication device for determining a vehicle cabin interior of the vehicle as the communication area, the vehicle cabin interior being the first area; a vehicle cabin exterior communication device serving as the second communication device for determining a lock area set in advance in a vehicle cabin exterior of the vehicle as the communication area, the vehicle cabin exterior being the second area; a vehicle cabin interior determining device as the first area determining device configured to determine whether the mobile devices are present in the vehicle cabin interior based on a reception condition of the response signals in response to the vehicle cabin interior communication device transmitting the simultaneous response request signal; a vehicle cabin exterior determining device as the second area determining device, which is configured to determine whether the mobile devices are present in the locking area based on a communication state between the vehicle cabin exterior communication device and the mobile devices, wherein the control execution device is further configured to lock doors of the vehicle in response to the vehicle cabin interior determining device determines that none of the mobile devices is present in the vehicle cabin interior; and the vehicle cabin exterior determining device determines that the at least one of the mobile devices is present in the locking area. [3] The vehicle authentication device according to claim 2, wherein the vehicle cabin interior determination device is further configured to transmit, while waiting for reception of the response signals corresponding to the simultaneous response request signal, in response to receiving a quasi-signal as noise having a predetermined signal strength, a time difference response request signal for requesting the mobile devices to respectively return the response signals at different, non-overlapping timings. [4] Vehicle authentication device according to claim 3, wherein the vehicle cabin interior determination device is further designed transmit the simultaneous response request signal a plurality of times; and confirm a determination that none of the mobile devices is present in the vehicle cabin interior in response to the vehicle cabin interior determination device not receiving the response signals and the quasi-signal corresponding to the simultaneous response request signal. [5] The vehicle authentication device according to any one of claims 2 to 4, wherein the vehicle cabin exterior determination device is further configured a time difference response request signal for requesting the mobile devices to return the response signals at different times that do not overlap; and in response to receiving the at least one of the respective response signals from the mobile devices, determine that the at least one of the mobile devices is present in the locking area. [6] Vehicle authentication device according to one of claims 2 to 5, wherein, in a situation in which the vehicle cabin exterior determination device determines that the at least one of the mobile devices is present in the locking area by performing wireless communication with the at least one of the mobile devices through the vehicle cabin exterior determination device, the vehicle cabin exterior determination device is further configured to identify the at least one of the mobile devices present in the locking area based on contents of the response signal from the at least one of the mobile devices, and wherein the vehicle cabin interior determination device is further designed after the vehicle cabin exterior determination device has determined that the at least one of the mobile devices is present in the locking area, to determine, in collaboration with the vehicle cabin interior communication device, whether one or more of the mobile devices are present in the vehicle cabin interior; and transmitting a signal for requesting one or more of the mobile devices other than the at least one of the mobile devices whose presence in the locking area is determined by the vehicle cabin exterior determining device to return the response signal simultaneously. [7] A vehicle authentication device according to any one of claims 2 to 5, further comprising: a door closing detector (F1) designed to detect a situation in which all of the doors of the vehicle are closed; and a locking instruction determining device (F2) configured to determine, based on an output signal of an input device configured to receive the instruction to lock the doors from the user, whether a user issues an instruction to lock the doors, wherein the vehicle cabin interior determining device is further configured, in response to the door closure detector detecting that all doors are locked, to determine, in collaboration with the vehicle cabin interior communication device, whether the mobile devices are present in the vehicle cabin interior, and wherein the vehicle cabin exterior determining device is further configured, in response to the locking instruction determining device determining that the user has issued the instruction to lock the doors, to determine whether the mobile devices are present in the locking range by performing wireless communication with the mobile devices via the vehicle cabin exterior communication device.

Images