JP2018071047A - Electronic key system and security unit and electronic key used in the system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic key system capable of more easily implementing countermeasures against relay attack, a security unit, and an electronic key.SOLUTION: An electronic key system 1 is provided with an in-vehicle device 10 and an electronic key 30, in which a predetermined process is executed by the in-vehicle device 10 when a predetermined wireless communication process is established between the in-vehicle device 10 and the electronic key 30, the electronic key system further comprising a security unit 60 having a non-contact tag 60a for short-range wireless communication. The electronic key 30 is provided with a tag communication unit 36 for wirelessly communicating with the non-contact tag 60a of the security unit 60, and is configured such that when the short range wireless communication between the tag communication unit 36 and the non-contact tag 60a of the security unit 60 is possible, a predetermined wireless communication process with the in-vehicle device 10 is executed, and when the short range wireless communication is impossible, the predetermined wireless communication process with the in-vehicle device 10 is not executed.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electronic key system, a security unit, and an electronic key, and more particularly, an electronic key system in which a predetermined vehicle operation is executed by an operation of a user carrying the electronic key, and a security unit and an electronic key used in the system About.

  Conventionally, a vehicle having a smart keyless function is known. In such a vehicle, a user carrying an electronic key performs a predetermined operation only by performing a predetermined operation. By using the smart keyless function, for example, when the door is automatically unlocked and the door is closed simply by touching a sensor provided on the door knob (or simply pressing a switch provided on the door). The door is automatically locked only by operating the operation unit provided in the vehicle, and the engine is started only by pressing the engine switch.

  In order to execute such a smart keyless function, the in-vehicle device mounted on the vehicle due to the above operation and the electronic key carried by the user execute a predetermined communication process between them. Then, when this communication process is established (that is, authentication is established), a predetermined process is executed in the vehicle via the in-vehicle device.

  In the above communication processing, normally, the communicable distance from the electronic key to the in-vehicle device is relatively long (for example, several tens of meters or more), but the communicable distance from the in-vehicle device to the electronic key is set short (for example, about 1 m) Has been. For this reason, the user carrying the electronic key can effectively operate the smart keyless function when in the vicinity of the vehicle or in the vehicle. That is, when the user (that is, the electronic key) is located at a position away from the communication distance of about 1 m from the vehicle, for example, even if a third person touches the door knob sensor, the door is not unlocked.

  However, in recent years, it has become clear that there is a theft technique called relay attack. This technique activates the smart keyless function by amplifying communication radio waves with a repeater and establishing the communication process between the electronic key and the vehicle-mounted device far away from each other. In order to prevent theft by such a relay attack, as a relay attack countermeasure, a technique for stopping the smart keyless function by the user's intention has been proposed (for example, see Patent Document 1). With the technique described in Patent Document 1, for example, the user can temporarily stop the smart keyless function by performing a specific stop operation using an electronic key.

JP-A-2016-79600

  However, in the technique described in Patent Document 1, in order to stop the smart keyless function as a countermeasure against relay attacks, the user needs to perform a specific stop operation. For this reason, there has been a problem that if this stop operation is not executed, it is possible to perform a relay attack.

  The present invention has been made to solve such a problem, and an object thereof is to provide an electronic key system, a security unit, and an electronic key that can more easily execute a countermeasure against a relay attack. .

  In order to achieve the above object, the present invention includes an in-vehicle device mounted on a vehicle and an electronic key capable of wireless communication with the in-vehicle device, and a predetermined wireless communication is performed between the in-vehicle device and the electronic key. An electronic key system in which predetermined processing is executed by an in-vehicle device when communication processing is established, further comprising a security unit having a non-contact tag for near field communication, and the electronic key A tag communication unit for wirelessly communicating with the contact tag and a short-range wireless communication between the tag communication unit and the non-contact tag of the security unit are possible. The wireless communication process is executed, but when the short-range wireless communication is not possible, the wireless communication process is configured not to execute the predetermined wireless communication process with the in-vehicle device.

  According to the present invention configured as described above, in the case where the electronic key is not located within the communication range capable of short-range communication with the security unit, the short-distance wireless communication between the electronic key and the security unit is impossible. Therefore, a predetermined wireless communication process is not executed between the electronic key and the in-vehicle device, and this wireless communication process is not established. Thus, in the present invention, for example, after the vehicle is driven and parked in the parking lot, the user only keeps the electronic key away from the security unit, and the user can perform smart keyless operation without performing any special operation. The function can be disabled and relay attack countermeasures can be easily implemented. Further, according to the present invention, when the user uses the vehicle, the electronic key and the security can be maintained only by maintaining the electronic key in the vicinity of the security unit (for example, connecting the electronic key and the security unit). Since the short-range wireless communication with the unit is possible, the user can activate the smart keyless function and cancel the relay attack countermeasure without performing any special operation.

In the present invention, it is preferable that the electronic key attempts near field communication with the non-contact tag of the security unit during execution of predetermined wireless communication processing with the in-vehicle device, and the near field communication is performed. Is not executable, the execution of the predetermined wireless communication process is stopped.
According to the present invention configured as described above, when a predetermined wireless communication process between the electronic key and the vehicle-mounted device is started to execute the smart keyless function, the electronic key communicates with the security unit in a short-range wireless communication. If this short-range wireless communication is not established, execution of a predetermined wireless communication process between the electronic key and the in-vehicle device is stopped. As described above, according to the present invention, it is possible to determine whether or not the short-range wireless communication between the electronic key and the security unit is possible with the wireless communication processing between the electronic key and the vehicle-mounted device. .

Preferably, in the present invention, the security unit transmits a wireless signal including predetermined information continuously or intermittently using a non-contact tag, and the electronic key transmits a wireless signal including predetermined information from the security unit. In response to the reception, a transition is made to a normal mode in which a predetermined wireless communication process is executed for a predetermined period, and a transition to a stop mode in which the predetermined wireless communication process is not executed when a predetermined period elapses after the transition to the normal mode. .
According to the present invention configured as described above, the security unit voluntarily transmits a radio signal including predetermined information, and by receiving the radio signal, the electronic key indicates that the security unit is located in the vicinity. Recognizable. In the present invention, when the electronic key receives a wireless signal from a security unit located in the vicinity, the electronic key shifts to a normal mode for executing a predetermined wireless communication process with the in-vehicle device for a predetermined period. The process comes to hold. On the other hand, when the distance between the electronic key and the security unit increases and the electronic key cannot receive a radio signal from the security unit and a predetermined period elapses, the mode shifts to a stop mode in which predetermined wireless communication processing with the in-vehicle device is not executed Therefore, this predetermined wireless communication process is not established. As described above, according to the present invention, it is possible to determine whether or not short-range wireless communication between the electronic key and the security unit is possible by spontaneous transmission of the wireless signal from the security unit.

  Further, in order to achieve the above object, the present invention provides an in-vehicle device when a predetermined wireless communication process is established between an in-vehicle device mounted on a vehicle and an electronic key capable of wireless communication with the in-vehicle device. A security unit used in an electronic key system in which predetermined processing is executed by a machine, and the electronic key is in a situation where short-range wireless communication with the security unit is possible The predetermined wireless communication process is executed, but when the short-range wireless communication is not possible, the predetermined wireless communication process is not executed, and the security unit is used for short-range wireless communication with the electronic key. A non-contact tag is provided, and the non-contact tag is characterized by transmitting a radio signal including predetermined information for short-range wireless communication with the electronic key.

  In the present invention, it is preferable that the non-contact tag transmits predetermined information in response to receiving the short-range wireless communication signal from the electronic key.

  In the present invention, it is preferable that the contactless tag continuously or intermittently transmits a radio signal including predetermined information.

In the present invention, preferably, the battery has a battery that can be charged by a household power source and a power plug for connection to the household power source, and the non-contact tag is operated by power supplied from the battery.
According to the present invention configured as described above, the battery is charged by connecting the power plug of the security unit to the household power supply, so that the electronic key and the security unit are separated when the vehicle is not in use. It is easy to give an incentive to hold. As a result, in the present invention, when parking a vehicle that is susceptible to relay attack, the smart keyless function can be invalidated and relay attack countermeasures can be implemented.

  Further, in order to achieve the above object, the present invention provides an in-vehicle device when a predetermined wireless communication process is established between an in-vehicle device mounted on a vehicle and an electronic key capable of wireless communication with the in-vehicle device. An electronic key used in an electronic key system in which predetermined processing is executed by a machine, and the electronic key includes a tag communication unit for short-range wireless communication with a security unit different from the in-vehicle device. When the short-range wireless communication between the communication unit and the security unit is possible, the predetermined wireless communication processing is executed with the on-vehicle device, but when the short-range wireless communication is not possible, the on-vehicle device It is characterized by not performing a predetermined | prescribed radio | wireless communication process between.

In the present invention, it is preferable that the electronic key is capable of performing short-range wireless communication with the security unit while performing predetermined wireless communication processing with the in-vehicle device. If not, execution of the predetermined wireless communication process is stopped.
In the present invention, it is preferable that the electronic key shifts to a normal mode for executing a predetermined wireless communication process for a predetermined period in response to receiving a wireless signal including predetermined information from the security unit. When a predetermined period elapses after the shift to, the mode shifts to a stop mode in which a predetermined wireless communication process is not executed.

  According to the electronic key system, the security unit, and the electronic key of the present invention, it is possible to more easily execute countermeasures against relay attacks.

It is a block diagram of the electronic key system of embodiment of this invention. It is explanatory drawing when the smart keyless function becomes effective (FIG. 2 (A)) and becomes invalid (FIG. 2 (B)) in the electronic key system of the embodiment of the present invention. It is explanatory drawing of the flow of a basic process of the smart keyless function in the electronic key system of embodiment of this invention. It is explanatory drawing of the flow of a stop process of the smart keyless function in the electronic key system of the 2nd Embodiment of this invention. It is explanatory drawing of the flow of a process of the smart keyless function in the electronic key system of the 2nd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
First, the configuration of the electronic key system of the present invention will be described with reference to FIG. FIG. 1 is a block diagram of an electronic key system.

  As shown in FIG. 1, the electronic key system 1 of this embodiment includes an in-vehicle device 10 mounted on a vehicle 2, an electronic key 30 that can be carried by a user, and a security unit 60. In the electronic key system 1, a predetermined process is executed in the vehicle 2 only by a user carrying the electronic key 30 performing a predetermined operation by the smart keyless function. Specifically, the door lock mechanism is automatically unlocked when the user simply touches the door knob to open the door of the vehicle 2, and the door switch provided on the vehicle 2 is pressed when the door is closed. Only the door lock mechanism is automatically locked, and the engine is started only by pressing the engine switch.

  The electronic key system 1 can temporarily disable the smart keyless function as a countermeasure against relay attack (stop mode). Specifically, in the present embodiment, the user enters the stop mode while the electronic key 30 is separated from the security unit 60 by a distance at which short-range wireless communication is not possible, and the vehicle 2 can be protected from the relay attack. .

The in-vehicle device 10 includes a control unit 11, an LF transmission unit 13, an RF reception unit 15, a memory 17, and an operation unit 19.
The control unit 11 includes a CPU and the like, and controls signals (lock command signal, unlock command signal, engine start command signal) to the door lock mechanism 50 and the engine control system 52 of the vehicle 2 based on communication processing with the electronic key 30. ) Is output.

The LF transmission unit 13 includes a transmitter and a transmission antenna, and transmits an LF signal to the electronic key 30 based on a command from the control unit 11. The communicable distance of communication using the LF signal is set to be short so that communication is possible when the user is in the vicinity of the vehicle 2 or in the vehicle, and is, for example, about 1 m.
The RF receiving unit 15 includes a receiver and a receiving antenna, and outputs an RF signal received from the electronic key 30 to the control unit 11. The communicable distance of communication using the RF signal is set longer than that of the LF signal, and is, for example, about several tens of meters to 100 m.

  The memory 17 stores an application for the control unit 11 and necessary data. The memory 17 includes a key ID 20 and a vehicle ID 22 as data. The key ID 20 is unique ID information of the electronic key 30 dedicated to the vehicle 2 (that is, the in-vehicle device 10). The vehicle ID 22 is unique ID information of the vehicle 2.

  The operation unit 19 includes a touch sensor 19a, a door switch 19b, and an engine switch 19c. The touch sensor 19a is provided on the door knob of the vehicle 2, and is arranged so that the user's hand touches when the user puts his hand on the door knob to open the door. The touch sensor 19a outputs a detection signal (operation signal) when the user's hand touches or approaches. The door switch 19b is provided in the vehicle 2 and can be pressed by the user when closing the door. The door switch 19b outputs an operation signal when pressed. The engine switch 19c is provided in the passenger compartment and can be pressed by the user when starting the engine. The engine switch 19c outputs an operation signal when pressed.

The door lock mechanism 50 is provided at each door of the vehicle 2, and when receiving a lock command signal and an unlock command signal from the vehicle-mounted device 10, the door lock mechanism 50 locks (unlocks) and unlocks the door, respectively. It has become.
The engine control system 52 includes a control unit that controls the engine of the vehicle 2, and starts the engine when an engine start command signal is received from the in-vehicle device 10.

  The electronic key 30 includes a control unit 31, an LF reception unit 33, an RF transmission unit 35, a tag communication unit 36, a memory 37, and an operation unit 39. The in-vehicle device 10 and the electronic key 30 also function as a remote entry system in addition to the electronic key system. For this reason, the electronic key 30 is also used as a remote controller for the remote entry function.

  The control unit 31 includes a CPU and the like, and is configured to execute communication processing with the in-vehicle device 10 and the security unit 60.

The LF reception unit 33 includes a receiver and a reception antenna, and outputs the LF signal received from the in-vehicle device 10 to the control unit 31.
The RF transmission unit 35 includes a transmitter and a transmission antenna, and transmits an RF signal to the in-vehicle device 10 based on a command from the control unit 31.

  The tag communication unit 36 includes a transmitter / receiver and a transmission / reception antenna, and performs short-range wireless communication with the security unit 60 based on a command from the control unit 31. That is, the electronic key 30 functions as a tag reader corresponding to the non-contact tag 60a included in the security unit 60. In this short-range wireless communication, the communicable distance is set to about 1 m. Note that in this specification, short-range wireless communication refers to a communication method that enables wireless communication at a short distance of about several centimeters to several meters.

  The memory 37 stores an application for the control unit 31 and necessary data. The memory 37 includes a key ID 40, a vehicle ID 42, a tag ID 46, and a stop mode flag 44 as data. The key ID 40 is unique ID information of the electronic key 30. The vehicle ID 42 is unique ID information of the vehicle 2. The tag ID 46 is unique ID information of the security unit 60 corresponding to the electronic key 30. The stop mode flag 44 is turned on when the execution of the smart keyless function is temporarily stopped (stop mode), and is turned off when the execution of the smart keyless function is valid (normal mode). .

  The operation unit 39 includes a lock switch 39a and an unlock switch 39b. When the electronic key system 1 functions as a remote entry system, the user can unlock and lock the door of the vehicle 2 by operating the operation unit 39 of the electronic key 30. That is, when the user presses the lock switch 39a and the unlock switch 39b, RF signals (lock signal and unlock signal) are output from the electronic key 30, and the vehicle-mounted device 10 that has received these RF signals causes the door lock mechanism 50 to receive the RF signal. Lock or unlock

  For example, when the user of the vehicle 2 carries the electronic key 30, the security unit 60 is carried along with the electronic key 30. For example, the security unit 60 can have a form of a key holder to which the electronic key 30 is attached or a form of a connection block that is connected to and integrated with the electronic key 30 so that the security unit 60 can be carried by the user. In addition, the security unit 60 may not be portable, and in this case, the security unit 60 can be disposed in the vehicle interior of the vehicle 2 or in the vicinity of the door.

  The security unit 60 includes a non-contact tag 60a having an IC chip structure for short-range wireless communication. The non-contact tag 60a includes a control unit 61, a transmission / reception unit 63, a memory 67, and a battery 65.

The control unit 61 includes a CPU and the like, and is configured to execute short-range wireless communication processing with the tag communication unit 36 of the electronic key 30.
The transmission / reception unit 63 includes a transmission / reception unit and a transmission / reception antenna, outputs a radio signal (tag request signal) received from the electronic key 30 to the control unit 61, and receives a radio signal (tag response signal) based on a command from the control unit 61. ).

  The memory 67 stores an application for the control unit 61 and necessary data. The memory 67 includes a key ID 70 and a tag ID 76 as data. The key ID 70 is unique ID information of the electronic key 30. The tag ID 76 is unique ID information of the security unit 60.

  The battery 65 supplies operating power to the control unit 61 and the like. The security unit 60 includes a power plug 66 for connecting to an external power source (for example, a household power source, a commercial power source, or a battery of the vehicle 2). In the present embodiment, the battery 65 can be charged by the external power source by connecting the security unit 60 to the external power source via the power plug 66. Further, the security unit 60 may be provided with a separate charger. In this case, the power plug 66 is connected to the charger connected to the external power source in a contact type or a non-contact type, and the external power source is connected via the charger. The battery 65 is charged.

  In the present embodiment, the non-contact tag 60 a is an active type, and transmits a radio signal via the transmission / reception unit 63 by power supply from the battery 65. Therefore, the user needs to charge the battery 65 periodically (for example, when the vehicle 2 is parked and returned home) by connecting the power plug 66 to the household power source.

  Further, the non-contact tag 60a may be a passive type. In this case, the wireless signal can be transmitted via the transmission / reception unit 63 by the power generated using the wireless signal (radio wave) received from the electronic key 30. is there. For this reason, since it is not necessary to use the electric power of the battery 65 for transmission / reception of a radio signal, the voltage drop of the battery 65 can be suppressed. The battery 65 is used to supply power to the electric circuit of the security unit 60 including the non-contact tag 60a, and assists when power generation using a radio signal received from the electronic key 30 cannot be performed sufficiently. Can also be used.

Next, enabling and disabling of the smart keyless function in the electronic key system of this embodiment will be described with reference to FIG. FIG. 2 is an explanatory diagram when the smart keyless function is enabled (FIG. 2A) and disabled (FIG. 2B).
In the electronic key system 1 of the present embodiment, the security unit 60 is used as means for enabling the smart keyless function.

  FIG. 2A shows a situation where the smart keyless function operates effectively. In FIG. 2A, the electronic key 30 is carried by the user, is located within a predetermined communicable distance (for example, 1 m) from the vehicle 2 (on-vehicle device 10), and is capable of short-range wireless communication with the security unit 60. It is located within a distance (for example, 1 m). In the present embodiment, the smart keyless function is effective in a situation where short-range wireless communication between the electronic key 30 and the security unit 60 can be performed.

  On the other hand, FIG. 2B shows a situation in which the smart keyless function is temporarily disabled as a countermeasure against relay attacks. In FIG. 2B, the electronic key 30 is located farther away than the distance at which the security unit 60 can perform near field communication. In the present embodiment, the smart keyless function is disabled in a situation where short-range wireless communication between the electronic key 30 and the security unit 60 cannot be performed. Therefore, if the user keeps the electronic key 30 away from the security unit 60 while not using the vehicle 2, the user can protect the vehicle 2 from the relay attack. In this case, the smart keyless function is disabled regardless of whether or not the electronic key 30 is located within a predetermined communicable distance from the vehicle 2 (onboard device 10).

  When the security unit 60 has a portable form, for example, after the user drives the vehicle 2 and returns home, the security unit 60 is separated from the electronic key 30 in order to charge the security unit 60 with a household power source. Since the smart keyless function is disabled (stop mode), it is possible to easily take measures against relay attacks. Further, when the security unit 60 is installed in the vehicle 2 or in the vicinity of the door, the smart keyless function is disabled (stop mode) when the user carries the electronic key 30 and gets off the vehicle 2. Therefore, it is possible to easily prevent relay attacks.

  Next, an outline of the smart keyless function in the electronic key system of the present embodiment will be described with reference to FIG. FIG. 3 is an explanatory diagram of a basic processing flow of the smart keyless function.

  First, when the user carrying the electronic key 30 operates any one of the operation units 19 provided in the vehicle 2 (S10), the control unit 11 of the in-vehicle device 10 applies a sensor or a switch operated from the operation unit 19 to the sensor or switch. A corresponding operation signal is received (S11). The control unit 11 transmits an LF signal based on the operation signal (S12). This LF signal is an authentication request signal and includes a vehicle ID 22.

  In the electronic key 30, the control unit 31 receives the LF signal via the LF receiving unit 33 (S21). When receiving the LF signal, the control unit 31 transmits a wireless signal to the security unit 60 via the tag communication unit 36 (S22). This wireless signal is a tag request signal and includes the key ID 40 of the electronic key 30.

  When the security unit 60 is located within the short-range wireless communication possible distance from the electronic key 30 (in the case of FIG. 2A), a wireless signal (tag request signal) is received from the electronic key 30 (S31), In response to reception of this radio signal, a radio signal (tag response signal) is transmitted (S32). That is, in the security unit 60, when the control unit 61 receives a wireless signal via the transmission / reception unit 63, in response thereto, the control unit 61 returns a wireless signal including the tag ID 76 of the security unit 60.

  Note that, when the security unit 60 receives a wireless signal, the control unit 61 may execute this wireless signal authentication process. In this authentication process, the key ID 40 included in the radio signal and the key ID 70 stored in the memory 67 can be verified. Then, if they match, the control unit 61 executes the above process (S32). If they do not match, the control unit 61 ignores the received radio signal and ends the process.

  On the other hand, when the security unit 60 is not located within the short-range wireless communication possible distance from the electronic key 30 (in the case of FIG. 2B), a wireless signal (tag request signal) is received from the electronic key 30. I can't. Therefore, even if the electronic key 30 transmits a wireless signal (tag request signal), the security unit 60 does not return a wireless signal (tag response signal).

  In the electronic key 30, the control unit 31 determines whether or not the wireless signal (tag response signal) returned from the security unit 60 via the tag communication unit 36 is received within a predetermined time from the transmission of the wireless signal (tag request signal). Is determined (S23). That is, the control unit 31 sets a reception window for receiving the tag response signal for a predetermined time, and determines whether or not to receive the tag response signal through this reception window.

  When the electronic key 30 receives the tag response signal within a predetermined time (S23; Yes, in the case of FIG. 2 (A)), the relay attack countermeasure is unnecessary and the control unit 31 is used to enable the smart keyless function. Transmits an RF signal via the RF transmitter 35 (S24), and ends the process. This RF signal is an authentication response signal and includes a vehicle ID 42 and a key ID 40 of the electronic key 30.

  Note that when the electronic key 30 receives a radio signal (tag response signal), the control unit 31 may execute the authentication process of the radio signal. In this authentication process, the tag ID 76 included in the wireless signal can be compared with the tag ID 46 stored in the memory 37. And when these correspond, the said process (S24) is performed, and when these do not correspond, the received radio signal is disregarded and a process is complete | finished.

  On the other hand, when the electronic key 30 does not receive the tag response signal within the predetermined time (S23; No, in the case of FIG. 2B), the control unit 31 disables the smart keyless function as a relay attack countermeasure. Turns on the stop mode flag 44 (shifts to the stop mode) and ends the process. In this case, as shown in FIG. 2B, the electronic key 30 is located farther from the security unit 60 than the short-range wireless communication possible distance, and short-range wireless communication is impossible between the two. .

  In the in-vehicle device 10, when the control unit 11 receives the RF signal returned from the electronic key 30 via the RF receiving unit 15 within a predetermined time from the transmission of the LF signal (S 13), the control unit 11 performs an authentication process of the RF signal. (S14). Specifically, the control unit 11 collates the vehicle ID 42 and key ID 40 included in the RF signal with the vehicle ID 22 and key ID 20 stored in the memory 17. If the RF signal is not received within a predetermined time from the transmission of the LF signal, the control unit 11 ends the process.

  In this authentication process, when the vehicle ID 42 and the key ID 40 are matched with the vehicle ID 22 and the key ID 20 (authentication is established), the in-vehicle device 10 receives the RF signal from the corresponding electronic key 30, so the control unit 11 Then, a predetermined control signal is transmitted (S15), and the process is terminated. On the other hand, when these IDs do not match (authentication is not established), the RF signal received by the in-vehicle device 10 is transmitted from other than the corresponding electronic key 30, and therefore the control unit 11 ignores the received RF signal. To end the process.

  As the predetermined control signal, when the touch sensor 19a is operated, an unlock command signal is output to the door lock mechanism 50, and when the door switch 19b is operated, a lock command signal is output to the door lock mechanism 50. When the engine switch 19c is operated, an engine start command signal is output to the engine control system 52.

  Thus, in the electronic key system 1, when the electronic key 30 is located in the vicinity of the security unit 60, the smart keyless function is enabled, and the user carrying the electronic key 30 performs a predetermined operation, so that the vehicle In step 2, a predetermined process is executed. That is, predetermined wireless communication processing (S12-S14, S21-S24) including transmission of an authentication request signal and return of an authentication response signal is executed between the in-vehicle device 10 and the electronic key 30, and this wireless communication is established. In this case, a predetermined process is automatically executed.

  On the other hand, in the electronic key system 1, when the electronic key 30 is located away from the security unit 60, the smart keyless function is disabled. That is, in the present embodiment, the electronic key 30 does not transmit an RF signal even if it receives an LF signal. For this reason, since the vehicle equipment 10 cannot perform the process of step S13-S15, a predetermined process is not performed. Therefore, the user can prevent the door of the vehicle 2 from being opened by the relay attack by keeping the electronic key 30 away from the security unit 60.

  Next, an outline of the smart keyless function in the electronic key system according to the second embodiment will be described with reference to FIGS. 4 and 5. FIG. 4 is an explanatory diagram of the flow of the smart keyless function stop process, and FIG. 5 is an explanatory diagram of the process flow of the smart keyless function. In FIG. 5, the same processes as those in FIG. 3 are denoted by the same process numbers, and redundant description is omitted.

  In the second embodiment, the security unit 60 transmits a wireless signal (tag identification signal) at a predetermined time, and when receiving the wireless signal, the electronic key 30 shifts to the normal mode for a predetermined period. Therefore, while the electronic key 30 is disposed in the vicinity of the security unit 60, the electronic key 30 automatically operates in the normal mode, thereby enabling the smart keyless function. On the other hand, since the electronic key 30 cannot receive the radio signal (tag identification signal) from the security unit 60 while the electronic key 30 is located away from the security unit 60, the electronic key 30 returns to the stop mode, thereby disabling the smart keyless function. Is done.

  4, in the security unit 60, the control unit 61 transmits a radio signal continuously (without interruption in time) or intermittently (for example, at intervals of 1 minute) (S41). This wireless signal is a tag identification signal and includes the tag ID 76 of the security unit 60.

  When the electronic key 30 is located in the vicinity of the security unit 60, the electronic key 30 receives the radio signal transmitted by the security unit 60 (S44). In the electronic key 30, when receiving the wireless signal via the tag communication unit 36, the control unit 31 collates the tag ID 76 included in the wireless signal with the tag ID 46 stored in the memory 37. If they match (authentication is established), the control unit 31 recognizes that the security unit 60 is located in the vicinity and short-range wireless communication is possible. On the other hand, if they do not match (authentication is not established), the received radio signal is not transmitted by the security unit 60 associated with the electronic key 30, so the process is terminated ignoring this radio signal.

  In the electronic key 30, when the wireless signal authentication is established, the control unit 31 turns off the stop mode flag 44 (shifts to the normal mode) and ends the process. In the present embodiment, the electronic key 30 remains in the normal mode for a predetermined time (for example, 2 minutes) after receiving the radio signal transmitted by the security unit 60, and keeps the stop mode flag 44 off. In addition, it is preferable that the duration for which the stop mode flag 44 is turned off is longer than the interval at which the electronic key 30 transmits a radio signal. However, when the predetermined time has elapsed, the electronic key 30 turns on the stop mode flag 44 and shifts from the normal mode to the stop mode in which the smart keyless function is disabled.

  Next, referring to FIG. 5, steps S10 to S15, S21 and S24 are the same as those in FIG. That is, when the user operates the operation unit 19 (S10), the in-vehicle device 10 receives an operation signal (S11). When receiving the operation signal, the in-vehicle device 10 transmits an LF signal (authentication request signal) as in step S12 of FIG. 2 (S12).

  The electronic key 30 receives this LF signal as in step S21 of FIG. 3 (S21). At this time, authentication processing may be executed in the same manner as described above. When receiving the LF signal, the control unit 31 determines whether or not the electronic key 30 is in the stop mode (whether the stop mode flag 44 is on or off) (S23a). If it is in the stop mode (S23a; Yes), the process is terminated. On the other hand, when not in the stop mode (S23a; No), the control unit 31 transmits an RF signal (authentication response signal) via the RF transmission unit 35 and ends the process. Further, when the in-vehicle device 10 receives the RF signal from the electronic key 30 (S13), the in-vehicle device 10 performs the same processing as steps S13 to S15 in FIG.

  As described above, in the present embodiment, the security unit 60 transmits a short-range wireless signal (tag identification signal) at a predetermined time, and the electronic key 30 shifts to the normal mode when the electronic key 30 receives the signal. And as long as the electronic key 30 is located in the vicinity of the security unit 60, and as long as short-distance wireless communication is possible, the electronic key 30 remains in the normal mode. On the other hand, in the present embodiment, when the electronic key 30 cannot receive the short-range wireless signal (tag identification signal) transmitted by the security unit 60 at a predetermined time, the electronic key 30 is returned to the stop mode.

  In the stop mode, even if the user (or a third party) operates the operation unit 19 of the vehicle-mounted device 10, the vehicle-mounted device 10 transmits an LF signal, and the electronic key 30 receives this LF signal. The electronic key 30 does not return an RF signal. Therefore, during the stop mode, the predetermined wireless communication process (S11 to S14, S21, S24) between the electronic key 30 and the vehicle-mounted device 10 is not established, so the predetermined process (door) related to the smart keyless function by the vehicle-mounted device 10 is not established. Lock, door unlock, engine start) are not executed. As described above, in this embodiment, the user can take a countermeasure against the relay attack only by keeping the electronic key 30 away from the security unit 60.

Next, the operation of the electronic key system 1 of the present embodiment will be described.
The present embodiment includes an in-vehicle device 10 mounted on the vehicle 2 and an electronic key 30 that can wirelessly communicate with the in-vehicle device 10, and a predetermined wireless communication process between the in-vehicle device 10 and the electronic key 30 ( 3 is an electronic key system 1 in which a predetermined process (S15) is executed by the vehicle-mounted device 10 when S11 to S15, S21 to S24 in FIG. 3 and S11 to S15 and S21 to S24 in FIG. 5 are established. . The electronic key system 1 of the present embodiment further includes a security unit 60 having a non-contact tag 60a for short-range wireless communication, and the electronic key 30 performs tag communication for wireless communication with the non-contact tag 60a of the security unit 60. When the short-range wireless communication between the tag communication unit 36 and the non-contact tag 60a of the security unit 60 is possible (S23; Yes, S23a; No), The predetermined wireless communication processing is executed between the devices, but when the short-range wireless communication is not possible (S23; No, S23a; Yes), the predetermined wireless communication processing is not executed with the in-vehicle device 10. Has been.

  As a result, in the present embodiment, when the electronic key 30 is located within a communication range in which near field communication with the security unit 60 is possible, short distance wireless communication between the electronic key 30 and the security unit 60 is possible. Therefore, a predetermined wireless communication process is not executed between the electronic key 30 and the in-vehicle device 10, and this wireless communication process is not established. Accordingly, in this embodiment, for example, after the vehicle 2 is driven and parked in the parking lot, the smart keyless function is invalidated simply by the user placing the electronic key 30 in the vicinity of the security unit 60. It is possible to easily execute countermeasures against attacks. In the present embodiment, when the user uses the vehicle 2, for example, while the electronic key 30 is picked up from the vicinity of the security unit 60 toward the vehicle 2, between the electronic key 30 and the security unit 60. Since short-range wireless communication becomes impossible, the relay attack countermeasure is automatically canceled and the smart keyless function can be activated.

  In the present embodiment, the electronic key 30 attempts short-range wireless communication with the non-contact tag 60a of the security unit 60 during execution of predetermined wireless communication processing with the in-vehicle device 10, and this When the distance wireless communication cannot be executed (S23; No), the execution of the predetermined wireless communication process is stopped. Thereby, in this embodiment, when the predetermined | prescribed wireless communication process between the electronic key 30 and the vehicle equipment 10 starts for execution of a smart keyless function, the electronic key 30 is short-distance wireless communication with respect to the security unit 60. If this communication is not established, execution of a predetermined wireless communication process between the electronic key 30 and the in-vehicle device 10 is stopped. As described above, in the present embodiment, it is determined whether or not short-range wireless communication between the electronic key 30 and the security unit 60 is possible, triggered by wireless communication processing between the electronic key 30 and the vehicle-mounted device 10. Can be determined.

  In the present embodiment, the security unit 60 transmits a wireless signal (tag identification signal) including predetermined information (tag ID 76) continuously or intermittently using the non-contact tag 60a. In response to reception of a wireless signal including predetermined information from the security unit 60, a transition is made to a normal mode in which a predetermined wireless communication process is executed for a predetermined period. Transition to stop mode in which communication processing is not executed. Thereby, in this embodiment, the security unit 60 spontaneously transmits a radio signal including predetermined information, and by receiving this radio signal, the electronic key 30 recognizes that the security unit 60 is located in the vicinity. Is possible. In this embodiment, when the electronic key 30 receives a wireless signal from the security unit 60 located in the vicinity, the electronic key 30 shifts to a normal mode in which a predetermined wireless communication process with the in-vehicle device 10 is executed for a predetermined period. This predetermined wireless communication process is established. On the other hand, when the distance between the electronic key 30 and the security unit 60 increases and the electronic key 30 cannot receive a radio signal from the security unit 60 and a predetermined period elapses, a predetermined wireless communication process with the in-vehicle device 10 is executed. Since this shifts to the stop mode, the predetermined wireless communication process is not established. As described above, in the present embodiment, it is determined whether or not the short-range wireless communication between the electronic key 30 and the security unit 60 is possible by the spontaneous transmission of the wireless signal of the security unit 60. Can do.

  Further, in the present embodiment, the battery 65 that can be charged by the household power source and the power plug 66 for connecting to the household power source are provided, and the non-contact tag 60a is operated by the power supplied from the battery 65. To do. Thereby, in this embodiment, since the user needs to charge the security unit 60 when the vehicle 2 is not used, it is easy to give the user an incentive to hold the electronic key 30 and the security unit 60 apart. Become. Thereby, in this embodiment, when parking the vehicle 2 which is easy to receive a relay attack, invalidation of a smart keyless function can be promoted and a relay attack countermeasure can be easily performed.

DESCRIPTION OF SYMBOLS 1 Electronic key system 2 Vehicle 10 Car equipment 30 Electronic key 50 Door lock mechanism 52 Engine control system 60 Security unit 60a Non-contact tag

Claims (10)

An in-vehicle device mounted on a vehicle, and an electronic key capable of wireless communication with the in-vehicle device, and when the predetermined wireless communication processing is established between the in-vehicle device and the electronic key, the in-vehicle device An electronic key system in which a predetermined process is executed by
A security unit having a contactless tag for near field communication;
The electronic key includes a tag communication unit for wirelessly communicating with the contactless tag of the security unit, and is capable of short-range wireless communication between the tag communication unit and the contactless tag of the security unit. If it is, the predetermined wireless communication process is executed with the in-vehicle device, but if the short-range wireless communication is not possible, the predetermined wireless communication process is not executed with the in-vehicle device. An electronic key system that is configured as follows.   The electronic key is capable of performing short-range wireless communication with the non-contact tag of the security unit during execution of the predetermined wireless communication process with the in-vehicle device. The electronic key system according to claim 1, wherein if there is not, execution of the predetermined wireless communication process is stopped. The security unit transmits a wireless signal including predetermined information continuously or intermittently using the contactless tag,
In response to receiving a wireless signal including the predetermined information from the security unit, the electronic key shifts to a normal mode for executing the predetermined wireless communication process for a predetermined period, and shifts to the normal mode. The electronic key system according to claim 1, wherein the electronic key system shifts to a stop mode in which the predetermined wireless communication process is not executed when the predetermined period elapses. Used in an electronic key system in which predetermined processing is executed by the in-vehicle device when a predetermined wireless communication processing is established between the in-vehicle device mounted on the vehicle and the electronic key capable of wireless communication with the in-vehicle device. Security unit,
The electronic key executes the predetermined wireless communication process with the in-vehicle device when the short distance wireless communication with the security unit is possible, but the short distance wireless communication is possible. If it is not a situation, it is configured not to execute the predetermined wireless communication process,
The security unit includes a contactless tag for short-range wireless communication with the electronic key, and the contactless tag receives a wireless signal including predetermined information for short-range wireless communication with the electronic key. The security unit to send.   The security unit according to claim 4, wherein the contactless tag transmits the predetermined information in response to receiving a short-range wireless communication signal from the electronic key.   The security unit according to claim 4, wherein the contactless tag continuously or intermittently transmits a wireless signal including the predetermined information.   The security according to claim 4, further comprising: a battery that can be charged by a household power source; and a power plug for connecting to the household power source, wherein the contactless tag is operated by power supplied from the battery. unit. Used in an electronic key system in which predetermined processing is executed by the in-vehicle device when a predetermined wireless communication processing is established between the in-vehicle device mounted on the vehicle and the electronic key capable of wireless communication with the in-vehicle device. An electronic key,
The electronic key includes a tag communication unit for short-range wireless communication with a security unit different from the in-vehicle device, and is capable of performing short-range wireless communication between the tag communication unit and the security unit. In this case, the predetermined wireless communication process is executed with the in-vehicle device, but when the short-range wireless communication is not possible, the predetermined wireless communication process is not executed with the in-vehicle device. Configured electronic key.   The electronic key, when performing the short-range wireless communication with the security unit during the execution of the predetermined wireless communication processing with the in-vehicle device, if this short-range wireless communication is not executable, The electronic key according to claim 8, wherein execution of the predetermined wireless communication process is stopped.   In response to receiving a radio signal including predetermined information from the security unit, the electronic key shifts to a normal mode in which the predetermined radio communication process is executed for a predetermined period, and shifts to the normal mode. The electronic key according to claim 8, wherein the electronic key shifts to a stop mode in which the predetermined wireless communication process is not executed when the predetermined period elapses.

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