JP2020007774A - Recognition system for vehicle, device of vehicle side, device of portable side, recognition method for vehicle, and recognition program for vehicle - Google Patents

Abstract

To provide a recognition system for a vehicle which can detect a relay attack without sending a signal for preventing the relay attack that is different from a request signal.SOLUTION: In a recognition system 100 for a vehicle that a vehicle-side device 10 and a portable-side device 20 are associated with each other by recognition information, the vehicle-side device 10 comprises a sending unit 111 which sends a request signal that includes a demand in a low frequency band, and includes noises having a predetermined strength distribution in a high frequency band by wireless, and a control unit 123 which performs predetermined control to a vehicle C, when an answer signal including the recognition information is received by a receiving unit 121. The portable-side device 20 comprises a determination unit 22 which determines whether or not a wireless signal received by a receiving unit 21 is the request signal that includes the demand in the low frequency band, and includes the noises of the predetermined strength distribution in the high frequency band, and a sending unit 25 which sends the answer signal including the recognition information by wireless, when the determination unit 22 determines that the wireless signal received by the receiving unit 21 is the request signal that includes the demand in the low frequency band, and includes the noises of the predetermined strength distribution in the high frequency band.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a vehicle authentication system, a vehicle authentication method, and a vehicle authentication program used for vehicle authentication.

  As a technology for controlling a vehicle keylessly, a technology is known in which a vehicle user operates a button of a portable device, a signal is transmitted from the portable device to the vehicle, and the vehicle unlocks a door lock. .

  In recent years, a so-called smart key system has been adopted to further improve convenience for users. In a smart key system, if a user has a portable device, the vehicle is controlled by automatic communication between the portable device and the vehicle, such as unlocking a door and starting an engine, even if the user does not operate the portable device. be able to. In a smart key system, a request signal is transmitted from a vehicle, and the request signal is received by a portable device carried by the user (that is, a smart key). If the user carrying the smart key is very close to the vehicle and the portable device can receive the request signal, the portable device transmits an answer signal including authentication information. The vehicle receives the answer signal, verifies the authentication information included therein, performs authentication, and controls the vehicle if the authentication is successful.

  However, such a smart key system may be abused against a legitimate user's intention due to a so-called relay attack, which is a so-called relay attack, and may cause disadvantage to a vehicle user.

  In a relay attack, an attacker, for example, places amplification repeaters near a vehicle and a user, amplifies a legitimate request signal, and remotely relays the signal to a portable device. Although passing through an unauthorized repeater, the request signal itself is legitimate, so the portable device transmits an answer signal. For this reason, the security of the vehicle is illegally released, and the vehicle can be aimed at or stolen in a place unknown to the user.

  In order to cope with such a problem, the vehicle-side transmitting unit is controlled so as to change the intensity of the request signal, and the portable device detects the intensity change pattern, thereby detecting an illegal request signal and performing a relay attack. A method for preventing such a situation has been proposed (Patent Document 1).

JP 2010-185186 A

  In the system disclosed in Patent Document 1, it is necessary for the vehicle to transmit an intensity measurement signal for preventing a relay attack as a signal different from the original unlock request signal.

  The present invention has been made in view of the above problems, and has as its object to provide a vehicle authentication system that can detect a relay attack without transmitting a relay attack prevention signal different from a request signal. I do.

  One embodiment of the present invention is a vehicular authentication system including a vehicle-side device mounted on a vehicle and a portable device having portability, wherein the vehicle-side device and the mobile-side device are associated by authentication information. The vehicle-side device wirelessly transmits a request signal including a request in a first frequency band and including a noise having a predetermined intensity distribution in a second frequency band higher in frequency than the first frequency band. A vehicle-side transmitting unit, a vehicle-side receiving unit that receives a radio signal, and a control unit that performs predetermined control on the vehicle when an answer signal including the authentication information is received by the vehicle-side receiving unit. The portable device includes a portable receiving unit that receives a wireless signal, the wireless signal received by the portable receiving unit includes the request in the first frequency band, and the second To the frequency band of A determining unit that determines whether or not the request signal includes the noise having a constant intensity distribution; and the determining unit determines that the wireless signal received by the mobile-side receiving unit is the first frequency band. And transmitting the answer signal including the authentication information by radio when determining that the request signal includes the noise having the predetermined intensity distribution in the second frequency band. And a part.

  According to this configuration, the vehicle-side device wirelessly transmits a request signal including a request for the first frequency band and noise having a predetermined intensity distribution in the second frequency band on the high frequency side. When a relay attack is performed, the noise intensity of the request signal is attenuated in a part of the band (particularly on the high frequency side), or part or all of the noise (particularly on the high frequency side) depending on the frequency characteristics of the repeater. It is cut and the original intensity distribution is changed. Therefore, when the request signal has a predetermined intensity distribution in the second frequency band, the portable device transmits the answer signal, so that the answer signal can be transmitted when there is no relay attack. As described above, by including noise having a predetermined intensity distribution in the request signal itself, a relay attack can be detected without transmitting a signal for preventing a relay attack different from the request signal.

  In the above-described vehicle authentication system, when the determination unit determines that the wireless signal received by the mobile-side reception unit does not include noise having the predetermined intensity distribution in the second frequency band. The mobile-side transmitting unit may not transmit the answer signal including the authentication information wirelessly.

  With this configuration, if the intensity distribution of the noise in the second frequency band changes due to the relay attack, the answer signal is not transmitted from the portable device, so that the vehicle control due to the relay attack can be reliably prevented.

  In the above-described vehicle authentication system, the noise may be white noise having a constant intensity distribution over the second frequency band.

  Since the noise characteristic represented by the power spectrum of the white noise is constant, there is an advantage that when the noise is deformed by using an incorrect amplifier, it can be easily detected.

  In the above vehicle authentication system, the second frequency band may be variable for each vehicle.

  If the frequency band to which noise is applied is different for each vehicle, it becomes difficult for an attacker to perform analysis, so that resistance to relay attacks can be maintained for a long time.

  Another aspect of the present invention is a vehicle-side device mounted on a vehicle and associated with a portable device by authentication information to constitute a vehicle authentication system, wherein the vehicle-side device has a first frequency band. Including a request, a transmitting unit that wirelessly transmits a request signal that includes noise having a predetermined intensity distribution in a second frequency band higher than the first frequency band, a receiving unit that receives a wireless signal, When the receiving unit receives an answer signal including the authentication information in response to the request signal, the control unit performs a predetermined control on the vehicle.

  Further, still another aspect of the present invention is a portable device that constitutes a vehicle authentication system associated with the vehicle device by the authentication information, the portable device, a receiving unit that receives a wireless signal, It is determined whether or not the wireless signal received by the receiving unit is a request signal including a request in a first frequency band and including noise having the predetermined intensity distribution in the second frequency band. A determining unit that determines whether the radio signal received by the receiving unit includes a request in a first frequency band, and has the predetermined intensity distribution in the second frequency band. When the request signal is determined to include the answer signal, the answer signal including the authentication information is wirelessly transmitted.

  Further, another aspect of the present invention includes a vehicle-side device mounted on a vehicle and a portable device having portability, and the vehicle-side device and the mobile-side device are associated with each other by authentication information. A vehicle authentication method in an authentication system, wherein the vehicle-side device includes a request in a first frequency band and a predetermined frequency in a second frequency band higher than the first frequency band. Transmitting a request signal including noise having an intensity distribution of: a step in which the portable device receives a wireless signal; and a step in which the portable device performs the request in the first frequency band as the wireless signal. And, when receiving the request signal including the noise of the predetermined intensity distribution in the second frequency band, wirelessly transmitting an answer signal including the authentication information. Step, the vehicle-side device receives a wireless signal, and the vehicle-side device performs predetermined control on the vehicle when the vehicle-side device receives an answer signal including the authentication information as the wireless signal. .

  Another aspect of the present invention is an authentication program for a vehicle, wherein the authentication program for a vehicle is mounted on a vehicle and is associated with a mobile device by authentication information to constitute a vehicle authentication system. Transmitting the request signal including the request in a first frequency band and wirelessly transmitting a request signal including the noise having the predetermined intensity distribution to a second frequency band higher in frequency than the first frequency band; A receiving step of receiving a signal; and a control step of causing the vehicle to perform predetermined control when receiving an answer signal including the authentication information in response to the request signal.

  Another aspect of the present invention is an authentication program for a vehicle, wherein the authentication program for a vehicle has portability, and is associated with a device on the vehicle side by authentication information to a mobile device that constitutes an authentication system for a vehicle. Receiving a radio signal, the radio signal received in the receiving step includes a request in a first frequency band, and noise having the predetermined intensity distribution in the second frequency band A determining step of determining whether the received signal is a request signal including the request signal, wherein the determining unit includes a request in a first frequency band, and the wireless signal received by the receiving unit; Transmitting the answer signal including the authentication information by radio when the request signal is determined to be the request signal including the noise having the predetermined intensity distribution in the band. The it has.

FIG. 1 is a diagram illustrating a normal use mode and a relay attack of the vehicle authentication system. FIG. 2 is a block diagram illustrating a configuration of the vehicle authentication system according to the embodiment of the present invention. FIG. 3 is a graph showing the intensity of the request signal for each frequency according to the embodiment of the present invention. FIG. 4 is a diagram illustrating processing in the determination unit according to the embodiment of the present invention. FIG. 5 is a graph showing an intensity distribution for each frequency of a request signal that has received a relay attack. FIG. 6 is a diagram illustrating a process in the case where a relay attack is performed in the determination unit according to the embodiment of the present invention. FIG. 7 is a flowchart of the vehicle authentication method executed in the vehicle authentication system according to the embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiment described below shows an example in which the present invention is implemented, and the present invention is not limited to the specific configuration described below. In carrying out the present invention, a specific configuration according to the embodiment may be appropriately adopted.

  FIG. 1 is a diagram illustrating a normal use mode and a relay attack of the vehicle authentication system. In FIG. 1, the upper part shows a normal use mode of the vehicle authentication system 100. The vehicle authentication system 1 includes a vehicle-side device 10 and a portable-side device 20. The vehicle-side device 10 is mounted on a vehicle, and the mobile-side device 20 is built in a portable smart key S.

The vehicle-side device 10 and the mobile-side device 20 are associated with each other by authentication information.
Therefore, the portable device 20 is effectively used for the specific vehicle device 10 associated with the authentication information. There may be a plurality of vehicle-side devices 10 with which one mobile-side device 20 is associated by authentication information. However, it is assumed that the number is so small that the probability that the vehicle-side device 10 associated with the same authentication information accidentally approaches the street is extremely small. Further, a plurality of portable devices 20 corresponding to one vehicle device 10 may be prepared.

  As shown in the upper part of FIG. 1, in a normal use mode, a request signal is wirelessly transmitted from the vehicle-side device 10 provided in the vehicle C, and the request signal is transmitted by the user U near the vehicle-side device 10. It is received by the device 20. When the portable device 20 exists within the receivable range of the request signal, the portable device 20 receives the request signal. The mobile device 20 wirelessly transmits an answer signal including authentication information according to a request included in the request signal. The vehicle-side device 10 performs authentication using the authentication information included in the answer signal from the mobile-side device 20. When the authentication is successful, the vehicle-side device 10 controls the vehicle control device 30 to perform predetermined vehicle control such as unlocking a door lock and starting an engine.

  Here, as a request signal transmitted from the vehicle-side device 10, an LF (kHz band) signal having a relatively narrow communication range is used in order to prevent unintended execution of authentication. This makes it possible to prevent authentication when the user carrying the mobile device 20 is sufficiently away from the vehicle. On the other hand, as the answer signal transmitted from the portable device 20, an RF (MHz band) signal having a relatively wide communication range is used.

  The lower part of FIG. 1 shows a situation in which a relay attack has been received. Upon receiving the relay attack, despite the fact that the user U having the mobile device 20 is sufficiently away from the vehicle C, a malicious third party (hereinafter, referred to as an “attacker”) A causes the user U to carry out the relay attack. Authentication is performed in the vehicle-side device 10, and vehicle control such as unlocking of the door lock of the vehicle C and starting of the engine is performed. As described above, the receivable range of the request signal is relatively narrow. Therefore, normally, when the mobile device 20 is sufficiently far from the vehicle device 10, the mobile device 20 cannot receive the request signal, and the answer signal is not transmitted from the mobile device 20.

  The attacker A prepares one or a plurality of repeaters 40 between the vehicle-side device 10 and the mobile-side device 20 that is sufficiently separated from the vehicle-side device 10, and thereby transmits the request signal to the mobile-side device 20. To communicate. Then, the portable device 20 can receive the request signal even though it is sufficiently far from the vehicle device 10, and transmits an answer signal in response to the received request signal. When the answer signal reaches the vehicle-side device 10, the vehicle-side device 10 performs authentication and allows various corresponding vehicle controls.

  The vehicular authentication system according to the present embodiment has a configuration for preventing the above-described relay attack. Hereinafter, the present embodiment will be described.

  FIG. 2 is a block diagram illustrating a configuration of the vehicle authentication system according to the embodiment of the present invention. The vehicle authentication system 100 includes a vehicle-side device 10, a mobile-side device 20, and a vehicle control device 30. The vehicle-side device 10 and the vehicle control device 30 are mounted on a vehicle. The vehicle device 10 is associated with a specific portable device 20 by authentication information. The vehicle-side device 10 and the portable-side device 20 thus associated with each other by the authentication information constitute a vehicle authentication system 100 for controlling the vehicle control device 30.

  The vehicle-side device 10 includes a request unit 11, an authentication unit 12, and a storage unit 13. The request unit 11 wirelessly transmits a request signal to the mobile device 20. The authentication unit 12 controls the vehicle control device 30 based on an answer signal transmitted from the portable device 20 in response to the request signal.

  Note that a plurality of request units 11 may be provided in one vehicle. That is, the vehicle is provided with a plurality of request units 11 such as a request unit 11 installed so that the request signal reaches only inside the vehicle and a request unit 11 installed so that the request signal reaches only near the vehicle outside the vehicle. Good. Further, in FIG. 2, the request unit 11 and the authentication unit 12 constitute the vehicle-side device 10 integrally, but they may be formed separately.

  The request unit 11 includes a transmission unit 111, a signal generation unit 112, and a request reception unit 113. The request receiving unit 113 receives a request from the vehicle control device 30. For example, when the user presses the engine start button, the vehicle control device 30 outputs an engine start request to the request unit 11. Alternatively, when the user touches the door knob, the vehicle control device 30 outputs a request to unlock or lock the door lock to the request unit 11. When the request receiving unit 113 receives a request, the signal generating unit 112 generates a request signal.

  FIG. 3 is a graph showing the intensity of the request signal for each frequency according to the embodiment of the present invention. As shown in FIG. 3, the request signal includes a request r and a noise n. In the request signal, the frequency band of the request r and the frequency band of the noise n are separated. Further, the frequency band of the noise n is higher than the frequency band of the request r. That is, the request signal includes the request r on the low frequency side and the noise n on the high frequency side. The noise n extends over a wide frequency band (that is, a wide band). Further, in the present embodiment, the noise n has a constant intensity over the wide band, that is, is white noise.

  The transmission unit 111 wirelessly transmits the request signal generated by the signal generation unit 112.

  The authentication unit 12 includes a receiving unit 121, an authentication unit 122, and a control unit 123. The receiving unit 121 receives a wireless signal. As will be described later, the mobile device 20 wirelessly transmits an answer signal including authentication information in response to the request signal, and thus the receiving unit 121 receives the answer signal. The authentication unit 122 authenticates the wireless signal received by the reception unit 121. The authentication unit 122 performs authentication using authentication information included in the wireless signal. The storage unit 13 stores authentication information for associating the vehicle-side device 10 with the mobile-side device 20. The authentication unit 122 performs authentication by comparing the authentication information stored in the storage unit 13 with the authentication information included in the wireless signal received by the reception unit 121.

  When the authentication by the authentication unit 122 is successful, that is, when the authentication information stored in the storage unit 13 matches the authentication information included in the wireless signal received by the reception unit 121, The vehicle is controlled by outputting a command for permitting the request to the vehicle control device 30. The vehicle control device 30 performs vehicle control such as unlocking or locking the door lock and starting the engine in accordance with the command.

  The mobile device 20 includes a reception unit 21, a determination unit 22, a storage unit 23, a signal generation unit 24, and a transmission unit 25. The receiving unit 21 receives a request signal wirelessly transmitted from the vehicle-side device 10. The determining unit 22 determines whether or not the request signal received by the receiving unit 21 has passed through a relay used in a relay attack. Specifically, the determination unit 22 determines whether the request signal received by the reception unit 21 includes a request on the low frequency side and noise having a predetermined intensity distribution on the high frequency side. .

  FIG. 4 is a diagram illustrating a process in the determination unit according to the embodiment of the present invention. The determination unit 22 includes a low-pass filter 221 and a subtractor 222. The request signal received by the receiving unit 21 includes the request r on the low frequency side and includes the noise n on the wide band on the high frequency side. The low-pass filter 221 cuts a high-frequency component from the request signal. As a result, only the part of the request r is extracted. The determination unit 22 analyzes the request r and grasps the content of the request r.

  The subtracter 222 extracts only the noise component by subtracting the output of the low-pass filter 221 from the received request signal. The determining unit 22 determines whether the intensity distribution of the noise component matches the noise intensity distribution of the normal request signal. The storage unit 23 stores the noise intensity distribution of the legitimate request signal, and the determination unit 22 refers to the storage unit 23 and obtains the noise intensity distribution of the legitimate request signal and the subtractor 222. With the obtained noise intensity distribution.

  When the determination unit 22 determines that the request signal received by the reception unit 21 has not passed through the relay used in the relay attack, the signal generation unit 24 generates an answer signal. The answer signal includes authentication information shared with the vehicle-side device 10. The transmitting section 25 wirelessly transmits the answer signal generated by the signal generating section 24.

  Next, the operation of the portable device 20 when a relay attack is performed will be described. FIG. 5 is a graph showing an intensity distribution for each frequency of a request signal that has received a relay attack. As described above, one or a plurality of repeaters are used in a relay attack. This repeater has a function as an amplifier for amplifying the request signal. The request signal that has passed through the repeater has its high-frequency band cut off due to the frequency characteristics of the amplifier. That is, as shown in FIG. 5, the request signal is applied with white noise having a constant signal intensity over a predetermined frequency band on the high frequency side. A part of the side (shown by a broken line in FIG. 5) is cut. Therefore, the noise n of the request signal that has received the relay attack becomes the noise n ′ whose intensity distribution is deformed.

  FIG. 6 is a diagram illustrating a process in the case where a relay attack is performed in the determination unit according to the embodiment of the present invention. The receiving unit 21 receives the request signal whose noise intensity distribution is deformed via the repeater. The low-pass filter 221 extracts the request r by cutting off the high-frequency component of such a request signal. The subtracter 222 extracts the noise n ′ by subtracting the request r extracted by the low-pass filter 221 from the received request signal.

  Then, the determination unit 22 determines whether or not the intensity portion of each frequency of the noise n ′ matches the intensity distribution stored in the storage unit 23. Since the intensity distribution of the noise n ′ whose intensity distribution has been deformed due to the relay attack does not match the intensity distribution of the noise in the normal request signal stored in the storage unit 23, the determination unit 22 receives the relay attack. Is determined.

  In this case, the signal generator 24 does not generate an answer signal, and thus the transmitter 25 does not transmit an answer signal. Therefore, the vehicle-side device 10 does not receive the answer signal from the portable-side device 20 even though the request signal is transmitted, and can effectively prevent the relay attack.

  Note that the portable device 20 may be provided with alarm means such as a buzzer, and an alarm may be issued when the determination unit 22 determines that a relay attack has been received. Further, in the above example, the signal generation unit 24 does not generate an answer signal when the determination unit 22 determines that a relay attack has been received, and the transmission unit 25 does not transmit an answer signal. However, instead of this, when it is determined that the relay attack has been received, the signal generation unit 24 may generate an answer signal indicating that vehicle control is not permitted, and transmit the answer signal from the transmission unit 25. Further, a warning means may be provided in the vehicle, and a warning may be issued by the warning means when receiving an answer signal indicating that vehicle control is not permitted.

  In the above embodiment, the configurations of the request unit 11 and the authentication unit 12 of the vehicle-side device 10 may be realized by a computer executing the vehicle authentication program according to the embodiment of the present invention. Further, the configurations of the receiving unit 21, the determining unit 22, the signal processing unit 24, and the transmitting unit 25 of the mobile device 20 may be realized by a computer executing the vehicle authentication program according to the embodiment of the present invention.

  FIG. 7 is a flowchart of the vehicle authentication method executed in the vehicle authentication system according to the embodiment of the present invention. The flow of the vehicle authentication method is executed by the vehicle-side device 10 and the portable-side device 20. First, the request receiving unit 113 of the vehicle-side device 10 receives a request from the vehicle control device 30 (Step S711). The signal generator 112 generates a request signal in response to the request received by the request receiver 113 (step S712).

  The transmitting unit 111 wirelessly transmits the request signal (step S713), and the receiving unit 21 of the portable device 20 receives the request signal (step S721). The determination unit 22 determines whether the request signal received by the reception unit 21 has received a relay attack (Step S722). When determining unit 22 determines that a relay attack has been received (YES in step S722), the process ends without generating and transmitting an answer signal. Alternatively, when it is determined that a relay attack has been received (YES in step S722), an answer signal indicating that authentication is not permitted may be generated and transmitted, as described above. .

  If the determination unit 22 determines that the received request signal has not received a relay attack (NO in step S722), the signal generation unit 24 generates an answer signal including authentication information (step S722). (S723), the transmitting unit 25 wirelessly transmits the generated answer signal (step S724).

  In the vehicle-side device 10, the receiving unit 121 of the authentication unit 12 receives the answer signal (step S714). The authentication unit 122 performs authentication by comparing the authentication information included in the answer signal with the authentication information stored in the storage unit 13 (step S715). If the authentication is successful (YES in step S715), the control unit 123 Controls the vehicle by outputting a command for permitting the request to the vehicle control device 30 (step S716). On the other hand, if the authentication in authentication section 122 fails (NO in step S715), the process ends without performing vehicle control.

  As described above, according to the vehicular authentication system of the present embodiment, broadband noise is applied to the high frequency side of the request signal. Therefore, when the request signal is subjected to a relay attack and the high frequency component is cut, the portable signal is transmitted. The side device can determine that. Therefore, even if a signal for preventing a relay attack is not generated and transmitted separately from the request signal, it is possible to detect a re-attack and prevent unauthorized authentication.

  In the above-described embodiment, the noise applied to the request signal is white noise having the same intensity over a predetermined band. The noise may have a distribution. Also in this case, the portable device 20 stores the intensity distribution, and determines that a relay attack has been received when the intensity distribution of the frequency band of the noise of the received request signal is different from the stored intensity distribution. be able to.

  From an attacker's point of view, in order to avoid the protection measures by the vehicle authentication system 100 of the present embodiment, the signal is appropriately amplified over the entire band (at least over the band to which noise is applied). It must be, but this is not easy. Therefore, the vehicular authentication system 100 of the present embodiment is an effective defense against an attacker performing a relay attack.

  Further, the frequency band or intensity distribution to which the noise is applied may be different for each vehicle. By doing so, even if an attempt is made to perform a relay attack corresponding to the vehicle authentication system 100 of the above-described embodiment, the attacker transmits a request signal to which band the noise is applied by the vehicle. Since it is not known in advance, it is necessary to discover the set band by trial and error, which is a stronger defense.

  The embodiments of the present invention have been described above, but the application of the present invention is not limited to the above-described embodiments. Vehicle authentication technology that is resistant to relay attacks can also be used to automate vehicle parking and trigger automatic driving with a view to its future realization.

  Further, the technology is not limited to the relationship between the vehicle-side device and the portable-side device as so-called car security, and is not limited thereto. A relay attack is a problem that can occur in all near- and middle-range wireless communication devices. INDUSTRIAL APPLICABILITY The present invention can be applied to, for example, measures against information leakage of home wireless devices, measures against privacy infringement due to unauthorized communication with small unmanned aerial vehicles such as drones, and measures against cargo theft.

100 vehicle authentication system, 10 vehicle-side device, 11 request unit,
111 transmission unit, 112 signal generation unit, 113 request reception unit, 12 authentication unit,
121 reception unit, 122 authentication unit, 123 control unit, 13 storage unit, 20 portable device, 21 reception unit, 22 determination unit, 221 low-pass filter, 222 subtractor,
23 storage unit, 24 signal generation unit, 25 transmission unit, 30 vehicle control device, U user,
A Attacker, r request, n noise, n 'noise with deformed intensity distribution

Claims (9)

A vehicle authentication system comprising a vehicle-side device mounted on a vehicle and a portable device having portability, wherein the vehicle-side device and the mobile-side device are associated by authentication information,
The vehicle-side device,
A vehicle-side transmitting unit that includes a request in a first frequency band and wirelessly transmits a request signal that includes a noise having a predetermined intensity distribution in a second frequency band higher than the first frequency band;
A vehicle-side receiving unit that receives a wireless signal;
When receiving an answer signal including the authentication information in the vehicle-side receiving unit, a control unit that performs predetermined control on the vehicle,
With
The portable device,
A mobile-side receiving unit that receives a wireless signal;
The wireless signal received by the portable-side receiving unit is the request signal including the request in the first frequency band and including the noise having the predetermined intensity distribution in the second frequency band. A determination unit for determining whether or not
In the determination unit, the wireless signal received by the mobile-side receiving unit includes the request in the first frequency band, and the noise of the predetermined intensity distribution in the second frequency band When it is determined that the request signal includes, the portable transmission unit wirelessly transmits an answer signal including the authentication information,
A vehicle authentication system comprising:   When the determination unit determines that the wireless signal received by the mobile-side reception unit does not include noise having the predetermined intensity distribution in the second frequency band, the mobile-side transmission unit includes: The vehicle authentication system according to claim 1, wherein the answer signal including the authentication information is not wirelessly transmitted.   The vehicle authentication system according to claim 1, wherein the noise is white noise having a constant intensity distribution over the second frequency band.   The vehicle authentication system according to any one of claims 1 to 3, wherein the second frequency band is variable for each vehicle. A vehicle-side device that is mounted on a vehicle and is associated with a portable device by authentication information to constitute a vehicle authentication system,
A transmitting unit that includes a request in a first frequency band and wirelessly transmits a request signal that includes a noise having a predetermined intensity distribution in a second frequency band on a higher frequency side than the first frequency band;
A receiving unit that receives a wireless signal;
When receiving an answer signal including the authentication information in the receiving unit in response to the request signal, a control unit that performs predetermined control on the vehicle,
A vehicle-side device comprising: A portable device that is associated with the vehicle device by the authentication information and forms a vehicle authentication system,
A receiving unit that receives a wireless signal;
It is determined whether or not the wireless signal received by the receiving unit is a request signal including a request in a first frequency band and including noise having the predetermined intensity distribution in the second frequency band. A determination unit to perform
The request signal, in which the request signal includes a request in a first frequency band and includes noise having the predetermined intensity distribution in the second frequency band. A portable device that wirelessly transmits an answer signal including the authentication information when it is determined that A vehicle authentication method in a vehicle authentication system, comprising a vehicle-side device mounted on a vehicle, and a portable device having portability, wherein the vehicle-side device and the mobile-side device are associated by authentication information.
A step in which the vehicle-side device includes a request in a first frequency band, and transmits a request signal including noise having a predetermined intensity distribution in a second frequency band higher in frequency than the first frequency band;
Wherein the portable device receives a wireless signal;
When the portable device includes, as the wireless signal, the request in the first frequency band, and receives the request signal including the noise having the predetermined intensity distribution in the second frequency band. Wirelessly transmitting an answer signal including the authentication information;
The vehicle-side device receives a wireless signal,
When the vehicle-side device receives an answer signal including the authentication information as the wireless signal, performing a predetermined control on the vehicle,
An authentication method for vehicles including: A vehicle-side device that is mounted on a vehicle and that is associated with the mobile-side device by the authentication information and configures a vehicle authentication system.
A transmission step of wirelessly transmitting a request signal including the request in a first frequency band and including the noise having the predetermined intensity distribution in a second frequency band on a higher frequency side than the first frequency band;
A receiving step of receiving a wireless signal;
A control step of performing predetermined control on the vehicle when receiving an answer signal including the authentication information in response to the request signal;
Vehicle authentication program to execute The portable device which has portability and is associated with the vehicle device by the authentication information and forms a vehicle authentication system,
A receiving step of receiving a wireless signal;
The wireless signal received in the receiving step includes a request in a first frequency band, and
A determining step of determining whether or not the request signal includes noise having the predetermined intensity distribution in the second frequency band;
In the determination unit, the received signal received by the receiving unit includes a request in a first frequency band, and the request signal including noise having the predetermined intensity distribution in the second frequency band When it is determined that is, a transmission step of wirelessly transmitting an answer signal including the authentication information,
Vehicle authentication program to execute

Images