JP5393717B2 - Electronic key device - Google Patents

Description

  The present invention relates to an electronic key device, and more particularly, to an electronic key device for locking and unlocking doors and trunks, starting an engine, and the like by collating an ID code by communication between a vehicle portable device and an in-vehicle device. .

  Conventionally, when locking and unlocking a door of a vehicle or starting an engine, a user inserts a key into a keyhole and rotates it, and keeps it in a user's pocket or bag like a so-called FOB key. Wireless communication was performed between the vehicle-mounted device and the key (portable device) without touching the key, and the ID code from the portable device was checked against the code stored in the vehicle-mounted device. There is a vehicle electronic key device that can start the engine simply by touching the sensor, and the vehicle-mounted device locks and unlocks the door, and simply presses a button attached to the driver's seat.

  Further, in the electronic key device as described above, when a sensor attached to the door knob is touched, a request signal for collation from the in-vehicle device is transmitted wirelessly, and the registered portable device is located around the vehicle. If the mobile device returns a response signal including a unique ID, the in-vehicle device can be attached to the smart keyless entry function that locks and unlocks the door by checking the response signal from the mobile device, or attached to the mobile device. When the door lock / unlock button is pressed, a lock / unlock signal is transmitted wirelessly from the portable device, and the in-vehicle device compares the signal and determines that it is a registered portable device. There was a remote keyless entry function.

  Examples of conventional keyless entry systems include those described in Patent Documents 1 and 2.

  The keyless entry system described in Patent Document 1 receives and analyzes a unique ID code transmitted from a transmitter and an unlocking signal according to the operation status of the operation switch, and the ID code is stored in advance. If the ID matches, the door is locked and unlocked.

  The keyless entry system described in Patent Document 2 receives an ID code transmitted from a portable device, and when the portable device is determined to be a vehicle interior, it prohibits locking from outside the vehicle interior and prevents confinement. To do.

Japanese Patent Laid-Open No. 11-62343 JP 2009-91841 A

  In each of the keyless entry systems described in Patent Documents 1 and 2, it is necessary to transmit a unique ID code, and it takes a communication time to transmit the unique ID code. Therefore, the response is delayed. In addition, there is a problem that battery consumption is increased. In addition, since the ID code is transmitted, there is a problem that a wireless signal including the ID code is intercepted and the electronic key may be copied.

  The present invention has been made to solve such a problem, and it is possible to determine whether or not the mobile device is a registered mobile device without transmitting the ID of the mobile device, and to transmit the transmission signal. Because it shortens, responsiveness can be improved, battery life can be extended, and even if communication is intercepted, it is difficult to decrypt the signal, it is difficult to duplicate the electronic key, and to improve safety It is an object to obtain an electronic key device that can be used.

The present invention includes an in-vehicle device mounted on a vehicle and a portable device possessed by a user, and the in-vehicle device authenticates the portable device by performing communication between the in-vehicle device and the portable device. In this case, the electronic key device drives a control device mounted on the vehicle, and the portable device stores a key ID that is a unique identification code of the own device and a key number that is a reference number of the own device. Portable device-side memory, portable device-side receiving means for receiving a request signal and an authentication signal from the in-vehicle device, portable device-side transmitting means for transmitting a request response signal and an authentication response signal for the in-vehicle device, and the in-vehicle device upon receiving the request signal transmitted from the machine, a request response means for transmitting a request response signal to the request signal to the vehicle device via the portable device-side transmission unit, after the request response signal transmission, before When the authentication signal transmitted from the in-vehicle device is received, the key number included in the authentication signal is compared with the key number of the portable device side memory, and when they match, they are included in the authentication signal The first authentication data consisting of random numbers is XOR- converted with the key ID of the memory to generate second authentication data, and an authentication response signal including the second authentication data is transmitted to the portable device side transmission means Portable device side conversion means for transmitting to the in-vehicle device via the device, the in-vehicle device is a key ID that is a unique identification code for each portable device registered in the own device, and each portable device registered in the own device a vehicle-side memory which stores the key number is a reference number, a vehicle-side transmitting means for transmitting the request signal and the authentication signal to the portable device, the request response signal and authentication response signal from the portable device And receiving the request response signal from the portable device with respect to the request signal transmitted to the portable device, generating a random number and generating the first authentication data. , An authentication unit that transmits the authentication signal including the first authentication data and a key number of the destination portable device to the portable device via the in-vehicle device transmission unit, and after the authentication signal is transmitted, When an authentication response signal including the second authentication data is received from a portable device, the second authentication data included in the authentication signal is XOR- converted with the key ID of the in-vehicle device side memory and 3 is generated, and the first authentication data and the third authentication data are compared, and if they match, the in-vehicle device side conversion means for determining that the authentication is established, and the authentication When established, the car It is an electronic key apparatus provided with the drive means which drives the said control apparatus mounted in both.

The present invention includes an in-vehicle device mounted on a vehicle and a portable device possessed by a user, and the in-vehicle device authenticates the portable device by performing communication between the in-vehicle device and the portable device. In this case, the electronic key device drives a control device mounted on the vehicle, and the portable device stores a key ID that is a unique identification code of the own device and a key number that is a reference number of the own device. Portable device-side memory, portable device-side receiving means for receiving a request signal and an authentication signal from the in-vehicle device, portable device-side transmitting means for transmitting a request response signal and an authentication response signal for the in-vehicle device, and the in-vehicle device upon receiving the request signal transmitted from the machine, a request response means for transmitting a request response signal to the request signal to the vehicle device via the portable device-side transmission unit, after the request response signal transmission, before When the authentication signal transmitted from the in-vehicle device is received, the key number included in the authentication signal is compared with the key number of the portable device side memory, and when they match, they are included in the authentication signal The first authentication data consisting of random numbers is XOR- converted with the key ID of the memory to generate second authentication data, and an authentication response signal including the second authentication data is transmitted to the portable device side transmission means Portable device side conversion means for transmitting to the in-vehicle device via the device, the in-vehicle device is a key ID that is a unique identification code for each portable device registered in the own device, and each portable device registered in the own device a vehicle-side memory which stores the key number is a reference number, a vehicle-side transmitting means for transmitting the request signal and the authentication signal to the portable device, the request response signal and authentication response signal from the portable device And receiving the request response signal from the portable device with respect to the request signal transmitted to the portable device, generating a random number and generating the first authentication data. , An authentication unit that transmits the authentication signal including the first authentication data and a key number of the destination portable device to the portable device via the in-vehicle device transmission unit, and after the authentication signal is transmitted, When an authentication response signal including the second authentication data is received from a portable device, the second authentication data included in the authentication signal is XOR- converted with the key ID of the in-vehicle device side memory and 3 is generated, and the first authentication data and the third authentication data are compared, and if they match, the in-vehicle device side conversion means for determining that the authentication is established, and the authentication When established, the car Since it is an electronic key device provided with drive means for driving the control device mounted on both sides, it is possible to determine whether or not it is a registered mobile device without transmitting the ID of the mobile device, and Because the transmission time of the transmission signal is shortened, the responsiveness can be improved and the battery life can be extended. Safety can be improved.

1 is an overall configuration diagram of an electronic key device according to Embodiments 1 and 2 of the present invention. It is explanatory drawing explaining the transmission signal of the electronic key apparatus which concerns on Embodiment 1, 2 of this invention. It is a time chart explaining the time communication process of the electronic key apparatus which concerns on Embodiment 1, 2 of this invention. It is a flowchart of operation | movement of the electronic key apparatus based on Embodiment 1 of this invention. It is a flowchart of operation | movement of the electronic key apparatus based on Embodiment 2 of this invention.

Embodiment 1 FIG.
An electronic key device according to Embodiment 1 of the present invention will be described. FIG. 1 is a conceptual diagram of the present apparatus, where 10 is an in-vehicle device mounted in a predetermined place of a vehicle such as an automobile, and 101 and 102 are portable devices A and B carried by the user. The electronic key device of the present invention comprises an in-vehicle device 10 and portable devices A and B.

  The in-vehicle device 10 includes a first transmission unit 11, a first CPU 12, a driving unit 15, and a first memory 16 inside. The first CPU 12 is provided with first communication signal ID conversion means 13. In FIG. 1, the first CPU 12 is illustrated as further including a communication signal decoding unit 14, but the communication signal decoding unit 14 is configured to be used in a second embodiment to be described later. In the first embodiment, it is not particularly necessary to provide it. The first memory 16 also has a Wake Up ID 17 as a start instruction code, a unique key number 18A, 18B (reference number) for each portable device 101, 102, and a unique number for each portable device 101, 102. Key IDs 19A and 19B (unique identification codes) and a delay time (or TM number indicating the delay time) (not shown) for each portable device 101 and 102 for providing a time difference at the time of transmission is stored. The delay time is a time set in advance for each portable device so that transmission signals do not collide between portable devices. Therefore, the in-vehicle device 10 can identify which portable device is the response signal by detecting the delay time of the received response signal after transmitting the transmission signal. In FIG. 1, the first memory 16 is illustrated as storing the encryption key 20, but since this is the configuration used in the second embodiment, in the first embodiment, There is no need to remember.

  Reference numeral 23 denotes a transmission antenna provided in the in-vehicle device 10, which is connected to the first transmission means 11 and transmits a request signal, an authentication signal, and the like to the portable devices A and B. 21 is a vehicle control device. Reference numeral 22 denotes a switch provided in the vehicle, such as a door locking / unlocking device or an engine starting device. Reference numeral 30 denotes a receiver provided in the in-vehicle device 10, and reference numeral 31 denotes a reception antenna provided in the receiver 30 for receiving request response signals, authentication response signals, and the like from the portable devices 101 and 102.

  On the other hand, since the portable devices 101 and 102 have the same configuration, only the portable device 101 will be described, and the description of the portable device 102 will be referred to. The portable device 101 includes a second transmission unit 110 having a transmission antenna 118, a reception IC 111 (IC: Integrated Circuit) having a reception antenna 119, a second CPU 116, and a battery 117.

  The second CPU 116 is provided with a second communication signal ID conversion unit 112, a second memory 114, and a reception unit 115 that receives a communication signal via the reception IC 111. In FIG. 1, the second CPU 116 is illustrated as including the communication signal encryption unit 113, but the communication encryption unit 113 is configured to be used in a second embodiment to be described later. In the first embodiment, it is not necessary to provide it. Further, the second memory 114 includes a key number unique to each portable device, a key ID for each portable device, and a TM number indicating a delay time for each portable device for providing a time difference between portable devices at the time of transmission. (Not shown) is stored. In FIG. 1, the second memory 114 is illustrated as storing an encryption key, but this is a configuration used in a second embodiment to be described later. Then there is no need to remember. At the time of an authentication response, the second CPU 116 converts the communication signal by the second communication signal ID conversion means 112 using the key ID stored in the memory 114 for each of the portable devices 101 and 102.

  In addition, the reception IC 111 is provided with an activation unit 120 for activating the second CPU 116, and a Wake Up ID 121 is registered in advance. In response to the request including the Wake Up ID 17 from the in-vehicle device 10, the activation unit 120 checks the Wake Up ID 121 and the Wake Up ID 17 registered in advance, and if they match, The CPU 116 is activated.

  The operation of the electronic key device according to the first embodiment will be described below with reference to FIG. 1, FIG. 2, FIG. 3, and FIG.

  FIG. 2 shows an example of the request signal 200 and the authentication signal 201 transmitted from the in-vehicle device 10 and an example of the request response signal 300 and the authentication response signal 301 transmitted from the portable devices 101 and 102 in the first embodiment. FIG. As shown in FIG. 2, the request signal 200 from the in-vehicle device 10 includes a Wake Up ID as a start instruction code, a response request code, challenge data, and a CRC check code. The authentication signal 201 from the in-vehicle device 10 includes a Wake Up ID as an activation instruction code, an authentication request key number, challenge data, and a CRC check code. Further, the request response signal 300 (300A and 300B in FIG. 3) from the portable devices 101 and 102 includes a synchronization signal and response data. The authentication response signal 301 from the portable devices 101 and 102 includes a synchronization signal, response data, and a CRC check code.

  FIG. 3 is a time chart showing temporal communication processing of transmission signals of the in-vehicle device 10 and the portable devices 101 and 102 in the first embodiment. As shown in FIG. 3, when the in-vehicle device 10 transmits a request signal 200, the portable devices 101 and 102 transmit request response signals 300A and 300B accordingly. The request response signals 300A and 300B are transmitted with a delay time (Delay time) corresponding to the TM number stored in the second memory 114 so as not to collide with each other. Next, when the in-vehicle device 10 transmits the authentication signal 201, the portable devices 101 and 102 transmit the authentication response signal 301 accordingly.

  FIG. 4 is a flowchart showing the operation of the electronic key device according to the first embodiment. Below, operation | movement is demonstrated using FIGS. 1-4. The electronic key device according to the first embodiment has a smart keyless entry function. In addition, in the following description, although operation | movement with the portable device 101 and the vehicle equipment 10 is demonstrated, since the operation | movement with the portable device 102 and the vehicle equipment 10 is also the same, refer to the following description for it. And

  In the electronic key device according to the first embodiment, first, when the user gets into the vehicle, the user possesses the portable device 101 registered in the in-vehicle device 10 mounted on the vehicle, and near the door knob of the vehicle. Touch a switch 22 such as a touch sensor attached to the touch panel. As a result, the first CPU 12 of the in-vehicle device 10 mounted on the vehicle is activated, and the CPU 12 requests to confirm whether or not the user has a portable device registered in the in-vehicle device 10. The signal 200 is transmitted by the first transmission unit 11 as a radio signal having a carrier frequency of 125 kHz, for example, at a level that reaches the vicinity of the vehicle. As shown in FIG. 2, the request signal 200 includes a wake-up ID 17 as an activation instruction code stored in the first memory 16 for activating the portable device 101, a response request code indicating a response request, It includes challenge data and a CRC check code. The challenge data at this time may be an arbitrary value, and may be generated by a random number, for example.

  Thereby, the portable device 101 possessed by the user receives the request signal 200 from the in-vehicle device 10 by the reception antenna 119 by the reception IC 111, and the Wake Up ID 17 included in the received request signal 200 is received in advance. It is determined whether or not the wake-up ID 121 registered in the IC 111 matches, and if the wake-up ID 121 matches, the second CPU 116 is activated by the activation unit 120. The second CPU 116 determines the reliability of the signal using, for example, a CRC check code included in the received request signal 200. If the second CPU 116 determines that the signal is a normal signal, the second CPU 116 and other response signals 300A In order not to collide with the response signal 300B from the portable device 102, a delay time corresponding to the TM number stored in the second memory 114 is provided (see FIG. 3), for example, a transmission speed with a carrier frequency of 315 MHz. The second response unit 110 transmits the request response signal 300A at 8 kbps. The configuration of the request response signal 300A is the same as the request response signal 300 shown in FIG. 2, and includes a synchronization signal and response data indicating that the signal is a response signal. The response data may be the same value as the challenge data included in the request signal 200. Note that the frequency and communication speed used for communication are not limited to the above case, and may be set as appropriate according to the function and environment to be used.

  When the in-vehicle device 10 receives the request response signal 300A transmitted from the registered portable device 101 by the receiving antenna 31 and the receiver 30, the first CPU 12 uses the transmission time of the request signal 200 as a base point, The delay time 401 of the request response signal 300A received from the portable device 101 is detected, and the detected value is compared with the delay time stored in the first memory 16, whereby the portable device of which key number is responded. It is determined whether or not the mobile device 101 that has responded is authenticated.

  That is, the in-vehicle device 10 transmits the authentication signal 201 including the Wake Up ID 17 as the activation instruction code to the portable device 101 that has responded to the request signal 200. As shown in FIG. 2, the authentication signal 201 includes, in addition to the Wake Up ID 17, challenge data that is a key number of the portable device 101 that requests authentication and a random number generated by the in-vehicle device 10 to authenticate the portable device 101. And a CRC check code for determining the reliability of the authentication signal 201. The challenge data is generated from, for example, a random number. In order to make the following explanation easy to understand, a specific example is given here, and the challenge data is, for example, “01 23 45” (hexadecimal number). Since the challenge data is generated from a random number every time authentication is performed in this manner, the challenge data changes for each authentication request, and security can be improved.

  When the portable device 101 confirms that the authentication signal 201 transmitted from the in-vehicle device 10 is correct with the CRC check code in the second CPU 116 and determines that the authentication signal 201 is correct, The key number stored in the second memory 114 is compared with the key number included in the authentication signal 201, and when the key numbers match, the request is made to the authentication signal 201. It is determined that this is a portable device. If the requested key number and the own key number match, the challenge data “01 23 45” (hexadecimal number) of the authentication signal 201 and the second memory 114 are stored in step S1 of FIG. When XOR conversion is performed on the key ID “55 AA 55” (hexadecimal number) of the portable device 101 by the second communication signal ID conversion unit 112, the obtained transmission data is “54 89 10” (hexadecimal number). Become. The transmission data obtained by this conversion is different from the challenge data transmitted as the authentication signal 201 from the in-vehicle device 101. The portable device 101 uses the transmission data thus obtained by XOR conversion as response data, adds a synchronization signal and a CRC check code to the response data, and transmits the response data to the in-vehicle device 10 as an authentication response signal 301.

  When the in-vehicle device 10 receives the authentication response signal 301, the first CPU 12 performs reliability determination using the CRC check code of the authentication response signal 301 in step S2 of FIG. 4 and determines that the signal is a normal signal. In step S3, the received response data “54 89 10” (hexadecimal number) and the key ID “55 AA 55” (hexadecimal number) of the portable device designated when the authentication signal 201 is transmitted are The communication signal ID conversion means 13 performs XOR conversion to obtain converted data “01 23 45” (hexadecimal number). Next, in step S4, the first CPU 12 compares the challenge data previously transmitted as the authentication signal 201 with the converted data, and if they match, the control by the switch 22 is executed in step S5. For this purpose, the door which is the control device 21 is unlocked by the driving means 15. In addition, although demonstrated as performing XOR conversion here, it is not limited to that case, About the conversion method, you may use conversion methods other than XOR conversion.

  If the CRC judgment does not match in step S2 of FIG. 4 or if it does not match when compared with the challenge data in step S4, authentication is not established and the process is terminated without executing the control.

  Thus, in the electronic key device according to the first embodiment, since the portable devices 101 and 102 do not transmit the key ID, the authentication time can be shortened and the responsiveness is improved, and at the same time, the battery 117 of the portable devices 101 and 102 is used. It is possible to extend the life of the product. Further, even if the key ID is not transmitted, the challenge data included in the transmitted signal is converted by the key ID, so that the key ID can be identified and does not operate erroneously with other portable devices. In addition, since the key ID is not transmitted, the key ID cannot be specified even if a wireless radio signal is intercepted, so that it is difficult to duplicate the portable device as an electronic key. Furthermore, since the key ID is not transmitted and the challenge data to be transmitted is generated every time the authentication is performed, the challenge data changes for each authentication request, and high security can be realized.

Embodiment 2. FIG.
Next, an electronic key device according to a second embodiment of the present invention will be described with reference to FIGS. 1 to 3 and FIG. The electronic key device according to the second embodiment is basically the same as the configuration of the first embodiment shown in FIG. 1 described above, but in the second embodiment, the portable devices 101 and 102 are replaced with the in-vehicle device. 10 is different from the first embodiment in that the signal is transmitted after being encrypted. Therefore, the following three points are different from the first embodiment.
(1) The communication signal encryption unit 113 is provided in the portable devices 101 and 102. After data is generated by XOR conversion on the portable devices 101 and 102 side, the communication signal encryption unit 113 encrypts the data. The point to be transmitted to the in-vehicle device 10 later
(2) The communication signal decryption unit 14 is provided in the in-vehicle device 10, and the encrypted signal received from the portable devices 101 and 102 is decrypted by the communication signal decryption unit 14 on the in-vehicle device 10 side.
(3) The same encryption key 20 is stored in advance in the memory 114 on the portable device 101, 102 side and the memory 16 on the in-vehicle device 10 side.

  Since other configurations and operations are basically the same as those in the first embodiment, description thereof is omitted here, and only differences from the first embodiment will be described in the following description.

  FIG. 5 is a flowchart showing a processing procedure of the electronic key device according to the second embodiment. In step S11, the same processing (XOR conversion) as that in step S1 described in the first embodiment is performed to generate transmission data. Next, in step S12, the generated transmission data is stored in the second memory 114. AES encryption is performed by the communication signal encryption unit 113 using an encryption key stored in advance. A CRC check code is added to the transmission data encrypted in this way, and the authentication response signal 301 is transmitted to the in-vehicle device 10.

  The in-vehicle device 10 first determines the authentication response signal 301 in step S13 by the first CPU 12 using the CRC check using the CRC check code to determine the reliability. The encrypted transmission data in the received authentication response signal 301 is decrypted using the same encryption key 20 as the encryption keys of the portable devices 101 and 102 stored in the first memory 16 in advance. A means 14 performs AES decoding. Here, AES is described as the encryption and decryption method, but another encryption method and decryption method may be used.

  Next, in step S15, the decrypted result is converted by XOR conversion by the first communication signal ID converting means 13 with the key ID of the portable device 101, 102 designated when the authentication signal 201 is transmitted. Get the data. This process is the same as step S3 in FIG.

  Next, in step S16, the challenge data transmitted as the authentication signal 201 is compared with the converted data. If they match, the drive means 15 performs control by the switch 22 in step S17. Then, the door which is the control device 21 is unlocked.

  If the CRC judgment does not match in step S13, or if it does not match when compared with the challenge data in step S16, the process is terminated without executing control as authentication failure.

  As described above, according to the second embodiment, the same effects as those of the first embodiment described above can be obtained. Further, in the second embodiment, the portable devices 101 and 102 further encrypt the communication signal. Therefore, even if a wireless radio signal is intercepted, it is possible to obtain an effect that it is further difficult to decode and copy.

  The electronic key device of the present invention can be applied not only to vehicles such as automobiles but also to all other vehicles such as motorcycles, ships, and aircrafts.

  DESCRIPTION OF SYMBOLS 10 Onboard machine, 11 1st transmission means, 12 1st CPU, 13 1st communication signal ID conversion means, 14 Communication signal decoding means, 15 Drive means, 16 1st memory, 17 Wake Up ID, 18 Key number, 19 Key ID, 20 Encryption key, 21 Control device, 22 Switch, 23 Transmitting antenna, 30 Receiver, 31 Receiving antenna, 101,102 Portable device, 110 Second transmitting means, 111 Receiving IC, 112 Second Communication signal ID conversion means, 113 communication signal encryption means, 114 second memory, 115 reception means, 116 second CPU, 117 battery, 118 transmission antenna, 119 reception antenna, 120 activation means, 121 Wake Up ID.

Claims (2)

When the in-vehicle device authenticates the portable device by providing the in-vehicle device mounted on the vehicle and the portable device possessed by the user, and performing communication between the in-vehicle device and the portable device, An electronic key device for driving a control device mounted on a vehicle,
The portable device is
A portable device memory that stores a key ID that is a unique identification code of the device and a key number that is a reference number of the device;
Portable device side receiving means for receiving a request signal and an authentication signal from the in-vehicle device;
Portable device side transmission means for transmitting a request response signal and an authentication response signal to the in-vehicle device;
When receiving the request signal transmitted from the in-vehicle device, a request response means for transmitting a request response signal for the request signal to the in-vehicle device via the portable device-side transmission means;
When the authentication signal transmitted from the in-vehicle device is received after the request response signal is transmitted, the key number included in the authentication signal is compared with the key number of the portable device side memory, and they match. The second authentication data is generated by XOR- converting the first authentication data consisting of a random number included in the authentication signal with the key ID of the memory, and an authentication response including the second authentication data Portable device side conversion means for transmitting a signal to the in-vehicle device via the portable device side transmission means,
The in-vehicle device is
An in-vehicle device side memory storing a key ID that is a unique identification code for each portable device registered in the own device, and a key number that is a reference number for each portable device registered in the own device;
On-vehicle device side transmission means for transmitting a request signal and an authentication signal to the portable device;
On-vehicle device side receiving means for receiving a request response signal and an authentication response signal from the portable device;
When the request response signal is received from the portable device with respect to the request signal transmitted to the portable device, a random number is generated to generate the first authentication data, and the first authentication data and Authentication means for transmitting the authentication signal including the key number of the portable device as the transmission destination to the portable device via the in-vehicle device side transmission means;
When the authentication response signal including the second authentication data is received from the portable device after the authentication signal is transmitted, the second authentication data included in the authentication signal is stored in the key of the in-vehicle device side memory. In-vehicle device that generates third authentication data by XOR conversion with ID, compares the first authentication data with the third authentication data, and determines that the authentication is successful if they match Side conversion means;
An electronic key device comprising: drive means for driving the control device mounted on the vehicle when the authentication is established. The portable device side memory and the in-vehicle device side memory further store the same encryption key,
The portable device further includes an encryption unit, and the authentication response signal is encrypted by the encryption unit and transmitted using the encryption key,
The in-vehicle device further includes a decryption unit, and when the encrypted authentication response signal is received from the portable device, the decryption unit decrypts the authentication response signal using the encryption key. 2. The electronic key device according to claim 1, wherein

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