WO2021124766A1

WO2021124766A1 - Electronic key system

Info

Publication number: WO2021124766A1
Application number: PCT/JP2020/042797
Authority: WO
Inventors: 宮澤　明
Original assignee: アルプスアルパイン株式会社
Priority date: 2019-12-17
Filing date: 2020-11-17
Publication date: 2021-06-24
Also published as: JP2023002854A

Abstract

The present invention addresses the problem of providing an electronic key system capable of preventing a relay attack on a vehicle. The problem is solved by an electronic key system having: a portable device carried by a person and provided with a first transmission/reception unit for transmitting and receiving a first radio wave and a control unit; an in-vehicle device installed in a vehicle and provided with a first transmission/reception unit for transmitting and receiving the first radio wave and a control unit; and a plurality of sensors attached to the vehicle and detecting an operation by the person. The electronic key system is characterized in that, when the operation by the person is detected by one of the plurality of sensors, the control unit of the in-vehicle device performs transmission and reception by the first radio wave between the in-vehicle device and the portable device, measures the distance between the in-vehicle device and the portable device, sets an accessible area corresponding to the sensor that has detected the operation by the person, and determines whether the location of the portable device based on the distance exists in the set accessible area.

Description

Electronic key system

The present invention relates to an electronic key system.

Conventionally, a smart keyless entry system including an in-vehicle device installed in a vehicle and a portable device owned by a user is known. In the smart keyless entry system, the user simply possesses the portable device within the communication area of the in-vehicle device, and the portable device and the in-vehicle device perform wireless communication with each other, so that various devices mounted on the vehicle (for example, Door locks, engine starters, etc.) can be controlled (keyless control) without using a physical key.

Relay attack is known as a method of stealing a vehicle that employs such a smart keyless entry system. Relay attack is a method in which a relay attack device relays a request signal transmitted from an in-vehicle device to a user's portable device away from the vehicle, thereby causing the portable device to transmit an answer signal and illegally keyless control the vehicle. Is.

For the purpose of preventing such a relay attack, for example, the signal strength of the strength measurement signal included in the request signal transmitted from the in-vehicle device is changed on the way, and the change in the signal strength is detected in the portable device. A technique for determining whether or not a relay attack has been performed is disclosed. According to this technology, the request signal relayed from the relay attack device does not reproduce the change in the signal strength of the signal for strength measurement, so that the request signal is invalid due to the relay attack in the portable device. Can be determined.

JP-A-2018-91071 JP-A-2019-31872

However, the above technology cannot sufficiently prevent relay attacks in vehicles. Therefore, there is a demand for an electronic key system that can more reliably prevent a relay attack in a vehicle.

According to one aspect of the present embodiment, a portable device carried by a person having a first transmission / reception unit for transmitting / receiving a first radio wave and a control unit, and a first transmission / reception unit for transmitting / receiving the first radio wave. And an in-vehicle device mounted on a vehicle provided with a control unit, and a plurality of sensors attached to the vehicle for detecting an operation by the person, and the control unit of the in-vehicle device is among the plurality of sensors. When the operation by the person is detected by one of the sensors, the vehicle-mounted device and the portable device perform transmission / reception by the first radio wave, and the distance between the vehicle-mounted device and the portable device. Is measured, an accessible area corresponding to the sensor in which the operation by the person is detected is set, and whether or not the position of the portable device based on the distance exists within the set accessible area. It is characterized by making a judgment.

According to the disclosed electronic key system, it is possible to prevent a relay attack in the vehicle.

Explanatory drawing of arrangement of electronic key system in vehicle in 1st Embodiment Configuration diagram of the electronic key system according to the first embodiment Explanatory drawing of electronic key system in 1st Embodiment (1) Explanatory drawing of the electronic key system in the first embodiment (2) Explanatory drawing of the electronic key system in the first embodiment (3) Explanatory drawing of the electronic key system in the first embodiment (4) Explanatory drawing of the electronic key system in the first embodiment (5) Flow chart of the control method of the electronic key system in the first embodiment Configuration diagram of the electronic key system according to the second embodiment

The mode for implementation will be described below. The same members and the like are designated by the same reference numerals and the description thereof will be omitted.

[First Embodiment]
By the way, in the relay attack, the request signal transmitted from the in-vehicle device is relayed to the portable device of the user away from the vehicle by the relay attack device, so that the portable device transmits an answer signal and the vehicle is illegally keyless controlled. How to do it. Therefore, it takes time because the request signal transmitted from the in-vehicle device needs to be relayed to the user's portable device away from the vehicle. The present invention has focused on this point and has come up with the idea of preventing a relay attack.

(Electronic key system)
The electronic key system according to the first embodiment will be described with reference to FIGS. 1 and 2. The electronic key system in the present embodiment has a plurality of sensors such as a portable device 10, an in-vehicle device 20, a first door sensor 31, a second door sensor 32, and a back door sensor 33. The first door sensor 31, the second door sensor 32, the back door sensor 33, and the like are touch sensors based on a capacitance method or the like.

The portable device 10 is a portable device carried by a person such as a driver of a vehicle 50, and is a control unit 11, a UWB (Ultra Wide Band) transmission / reception unit 12, an antenna 13, and a BLE (Bluetooth Low Energy) (registered trademark) transmission / reception unit 14. , Antenna 15, battery 16, and the like.

The on-board unit 20 is mounted on the vehicle 50 and has a control unit 21, a UWB transmission / reception unit 22, an antenna 23, a BLE transmission / reception unit 24, an antenna 25, and the like.

A plurality of sensors such as the on-board unit 20, the first door sensor 31, the second door sensor 32, and the back door sensor 33 are attached to the vehicle 50. Specifically, the in-vehicle device 20 is mounted inside the vehicle 50, the first door sensor 31 is mounted on the door handle of the door on the right side of the vehicle 50, and the second door sensor 32 is mounted on the left side of the vehicle 50. The back door sensor 33 is attached to the door handle of the back door that opens and closes the trunk behind the vehicle 50. Further, the vehicle 50 is provided with an engine start unit 34 for moving the vehicle 50. Therefore, the vehicle 50 is equipped with a plurality of sensors for detecting human operation.

Communication using UWB radio waves between the portable device 10 and the vehicle-mounted device 20 is performed, for example, by using radio waves having a frequency of 8 GHz, the UWB transmitter / receiver 12 and the antenna 13 of the portable device 10 and the UWB transmitter / receiver 22 and the antenna 23 of the vehicle-mounted device 20. It is done using and.

Further, in the communication by BLE between the portable device 10 and the in-vehicle device 20, for example, the BLE transmission / reception section 14 and the antenna 15 of the portable device 10 and the BLE transmission / reception section 24 of the in-vehicle device 20 are transmitted by radio waves having a frequency of 2.4 GHz. This is done using the antenna 25.

In the present embodiment, the UWB radio wave is described as the first radio wave, the UWB transmission / reception unit 12 and the UWB transmission / reception unit 22 are described as the first transmission / reception unit, and the BLE radio wave is described as the second radio wave. The BLE transmission / reception unit 14 and the BLE transmission / reception unit 24 may be referred to as a second transmission / reception unit. Therefore, the frequency of the first radio wave is higher than the frequency of the second radio wave.

(Control of electronic key system)
Next, the control of the electronic key system in the present embodiment will be described.

First, consider the case where the driver or the like of the vehicle 50 is detected by the first door sensor 31 of the vehicle 50. In this case, as shown in FIG. 3, the portable device 10 possessed by the driver or the like of the vehicle 50 exists in a region having a radius of 1 m or more and less than 3 m from the in-vehicle device 20. Therefore, when the driver or the like of the vehicle 50 is detected by the first door sensor 31 of the vehicle 50, the distance between the portable device 10 and the in-vehicle device 20 is set to the antenna 13 of the UWB transmission / reception unit 12 of the portable device 10. The distance between the UWB transmitter / receiver 22 of the vehicle-mounted device 20 and the antenna 23 is measured using UWB radio waves, and whether or not the portable device 10 exists in a region having a radius of 1 m or more and less than 3 m from the vehicle-mounted device 20. To judge. When the portable device 10 exists in an area having a radius of 1 m or more and less than 3 m from the vehicle-mounted device 20, the vehicle 50 controls to unlock or lock the door to which the first door sensor 31 is attached. Do.

That is, when the driver or the like of the vehicle 50 is detected by the first door sensor 31 of the vehicle 50, the on-board unit 20 transmits the UWB radio wave toward the portable device 10, and the portable device 10 receives the UWB radio wave. Turns back and transmits the UWB radio wave toward the in-vehicle device 20. In the in-vehicle device 20 that has received the UWB radio wave from the portable device 10, the portable device 10 is based on the time that the UWB radio wave is transmitted from the portable device 10 and the time that the in-vehicle device 20 receives the UWB radio wave from the portable device 10. The distance between the vehicle and the vehicle-mounted device 20 is calculated by the control unit 21 or the like. Such a distance calculation method is called a TOA (Time of Arrival) method.

Therefore, when detected by the first door sensor 31 of the vehicle 50, the accessible area where the portable device 10 is considered to exist, for example, as shown in FIG. 3, has a radius smaller than that of the vehicle-mounted device 20. When the portable device 10 is present in an area of 1 m or more and less than 3 m, the door to which the first door sensor 31 is attached is controlled to be unlocked or locked.

When the position of the portable device 10 based on the distance calculated by the vehicle-mounted device 20 exists in a region having a radius of less than 1 m or a radius of 3 m or more from the vehicle-mounted device 20, or as shown in FIG. When the portable device 10 exists in an area having a radius of 5 m or more from the in-vehicle device 20, it is considered that the operation is performed by a person who is not the owner of the portable device 10, so that the first door sensor 31 is used. Do not unlock or lock the attached door.

Next, consider the case where the driver or the like of the vehicle 50 is detected by the second door sensor 32 of the vehicle 50. In this case, as shown in FIG. 5, the portable device 10 owned by the driver or the like of the vehicle 50 exists in a region having a radius of 1 m or more and less than 3 m from the in-vehicle device 20.

Therefore, as in the case of the first door sensor 31, when the driver or the like of the vehicle 50 is detected by the second door sensor 32 of the vehicle 50, the distance between the portable device 10 and the in-vehicle device 20 is carried. The distance between the antenna 13 of the UWB transmission / reception unit 12 of the machine 10 and the antenna 23 of the UWB transmission / reception unit 22 of the vehicle-mounted device 20 is measured using UWB radio waves, and the portable device 10 has a radius of 1 m or more from the vehicle-mounted device 20. It is determined whether or not it exists in an area of less than 3 m. When the portable device 10 exists in an area having a radius of 1 m or more and less than 3 m from the in-vehicle device 20, the vehicle 50 controls to unlock or lock the door to which the second door sensor 32 is attached. Do.

It should be noted that the position of the portable device 10 based on the distance calculated by the vehicle-mounted device 20 exists in a region having a radius of less than 1 m or a radius of 3 m or more from the vehicle-mounted device 20, or is shown in FIG. As described above, when the portable device 10 exists in an area having a radius of 5 m or more from the vehicle-mounted device 20, the operation of unlocking or locking the door to which the second door sensor 32 is attached is not performed.

Next, consider the case where the driver or the like of the vehicle 50 is detected by the back door sensor 33 of the vehicle 50. In this case, as shown in FIG. 6, the portable device 10 owned by the driver or the like of the vehicle 50 exists in a region having a radius of 3 m or more and less than 5 m from the in-vehicle device 20. Therefore, when the driver or the like of the vehicle 50 is detected by the back door sensor 33 of the vehicle 50, the distance between the portable device 10 and the in-vehicle device 20 is determined by the antenna 13 of the UWB transmission / reception unit 12 of the portable device 10 and the in-vehicle device. The distance of the UWB transmitter / receiver 22 of the machine 20 to the antenna 23 is measured using UWB radio waves, and it is determined whether or not the portable device 10 exists in a region having a radius of 3 m or more and less than 5 m from the in-vehicle device 20. To do. When the portable device 10 exists in an area having a radius of 3 m or more and less than 5 m from the in-vehicle device 20, the vehicle 50 controls to unlock or lock the back door to which the back door sensor 33 is attached. ..

Therefore, when the driver or the like of the vehicle 50 is detected by the back door sensor 33 of the vehicle 50, the distance between the portable device 10 and the in-vehicle device 20 is calculated by the control unit 21 or the like, and based on the calculated distance. When the portable device 10 is present in an accessible area where the portable device 10 is considered to exist, for example, as shown in FIG. 6, a radius of 3 m or more and less than 5 m from the in-vehicle device 20. Controls the unlocking or locking of the back door to which the back door sensor 33 is attached.

If the position of the portable device 10 based on the distance calculated by the vehicle-mounted device 20 exists in an area having a radius of less than 3 m or a radius of 5 m or more from the vehicle-mounted device 20, the owner of the portable device 10 Since it is considered that the operation is performed by a person or the like, the operation of unlocking or locking the back door to which the back door sensor 33 is attached is not performed.

Next, consider the case where the driver or the like of the vehicle 50 gets into the inside of the vehicle 50 and touches it to operate the engine start unit 34. In this case, as shown in FIG. 7, the portable device 10 possessed by the driver or the like of the vehicle 50 exists in a region having a radius of less than 1 m from the vehicle-mounted device 20. Therefore, since the driver or the like of the vehicle 50 operates the engine start unit 34 of the vehicle 50, when touched, the distance between the portable device 10 and the in-vehicle device 20 is determined by the antenna of the UWB transmission / reception unit 12 of the portable device 10. The distance between 13 and the antenna 23 of the UWB transmitter / receiver 22 of the vehicle-mounted device 20 is measured using UWB radio waves, and it is determined whether or not the portable device 10 exists in a region having a radius of less than 1 m from the vehicle-mounted device 20. to decide. When the portable device 10 exists in a region having a radius of less than 1 m from the vehicle-mounted device 20, the engine start unit 34 is started to control the movement of the vehicle 50.

Therefore, when the driver or the like of the vehicle 50 touches to operate the engine start unit 34, the distance between the portable device 10 and the in-vehicle device 20 is calculated by the control unit 21 or the like, and based on the calculated distance, the distance is calculated. When the portable device 10 is present in an accessible area where the portable device 10 is considered to exist, for example, as shown in FIG. 7, a radius of less than 1 m from the in-vehicle device 20 is present. The engine start unit 34 is started to control the movement of the vehicle 50.

When the position of the portable device 10 based on the distance calculated by the vehicle-mounted device 20 exists in an area having a radius of 1 m or more from the vehicle-mounted device 20, it is an operation by a person who is not the owner of the portable device 10. Therefore, the engine start unit 34 does not start.

(Actual control of electronic key system)
Next, the actual control of the electronic key system according to the present embodiment will be described with reference to FIG.

First, in step 102 (S102), the operation is detected by the sensor or the like in the vehicle 50. Specifically, it is detected that the operation has been performed by touching any of the first door sensor 31, the second door sensor 32, the back door sensor 33, and the engine start unit 34 attached to the vehicle 50.

Next, in step 104 (S104), the accessible area of the portable device 10 is set corresponding to the detected sensor. Specifically, in step 102, when the detection is made by the first door sensor 31 or the second door sensor 32, the accessible area of the portable device 10 is set to 1 m or more and less than 3 m. When the back door sensor 33 detects it, the accessible area of the portable device 10 is set to 3 m or more and less than 5 m. If the engine start unit 34 detects it, the accessible area of the portable device 10 is set to less than 1 m.

Next, in step 106 (S106), UWB communication for measuring the distance between the vehicle-mounted device 20 and the portable device 10 is started. Specifically, based on the control of the control unit 21 of the vehicle-mounted device 20, the UWB radio wave is transmitted from the UWB transmission / reception unit 22 via the antenna 23. When the UWB transmission / reception unit 12 of the portable device 10 receives the UWB radio wave transmitted from the vehicle-mounted device 20 via the antenna 13, the UWB radio wave from the UWB transmission / reception unit 12 of the portable device 10 via the antenna 13 is controlled by the control unit 11. To send. When the UWB transmission / reception unit 22 of the vehicle-mounted device 20 receives the UWB radio wave transmitted from the portable device 10 via the antenna 23, in step 108 (S108), the control unit 21 of the vehicle-mounted device 20 receives the UWB radio wave from the vehicle-mounted device 20. The distance AX between the in-vehicle device 20 and the portable device 10 is calculated from the time when the in-vehicle device 20 is transmitted and the time when the UWB radio wave is received from the in-vehicle device 20.

Next, in step 110 (S110), it is determined whether or not the portable device 10 exists within the accessible area set in step 104 based on the distance AX between the vehicle-mounted device 20 and the portable device 10. When the portable device 10 exists in the accessible area set in step 104, the operation detected in step 102 is determined to be a normal operation, and the process proceeds to step 112. If the portable device 10 does not exist in the accessible area set in step 104, the operation detected in step 102 is determined to be an illegal operation and ends.

Next, in step 112 (S112), the position of the portable device 10 is estimated from the distance AX between the vehicle-mounted device 20 and the portable device 10, and in step 114 (S114), between the vehicle-mounted device 20 and the portable device 10. , BLE communication is started, and in step 116 (S116), the determination of ID authentication is made. When the ID authentication is performed, the process proceeds to step 118 (S118), and control signals such as unlocking and locking are transmitted. If the ID is not authenticated, the process ends without unlocking or locking.

The control of the electronic key system described above is performed by the control unit 21 of the in-vehicle device 20, but it can also be controlled by another control unit or the like inside the vehicle 50, and further, the control unit of the portable device 10. It is also possible to do it in 11.

[Second Embodiment]
Next, the second embodiment will be described. The electronic key system in the present embodiment measures the distance between the portable device and the in-vehicle device in the wavelength band of BLE communication, and uses radio waves of one wavelength.

As shown in FIG. 9, the electronic key system in the present embodiment is a portable device carried by a person such as a driver of a vehicle 50, and the control unit 11, the BLE transmission / reception unit 14, the antenna 15, and the like. It has a battery 16 and the like. Further, the vehicle-mounted device 120 is mounted on the vehicle 50 and has a control unit 21, a BLE transmission / reception unit 24, an antenna 25, and the like. In the present embodiment, both the distance measurement and the communication are performed using BLE radio waves. Therefore, in the present embodiment, the BLE radio wave becomes the first radio wave, and the BLE transmission / reception unit 14 and the BLE transmission / reception unit 24 function as the first transmission / reception unit.

The contents other than the above are the same as those in the first embodiment.

Although the embodiments have been described in detail above, the embodiments are not limited to the specific embodiments, and various modifications and changes can be made within the scope of the claims.

This international application claims priority based on Japanese Patent Application No. 2019-227696 filed on December 17, 2019, the entire contents of which are incorporated in this international application by reference here. Shall be.

10 Portable device 11 Control unit 12 UWB transmission / reception unit 13 Antenna 14 BLE transmission / reception unit 15 Antenna 16 Battery 20 In-vehicle device 21 Control unit 22 UWB transmission / reception unit 23 Antenna 24 BLE transmission / reception unit 25 Antenna 31 First door sensor 32 Second door sensor 33 Back Door sensor 34 Engine start unit 50 Vehicle

Claims

A portable device carried by a person having a first transmission / reception unit and a control unit for transmitting / receiving a first radio wave, and
An in-vehicle device mounted on a vehicle provided with a first transmission / reception unit and a control unit for transmitting / receiving the first radio wave, and
A plurality of sensors attached to the vehicle that detect the operation by the person,
Have,
The control unit of the in-vehicle device
When an operation by the person is detected by one of the plurality of sensors, the vehicle-mounted device and the portable device perform transmission / reception by the first radio wave, and the vehicle-mounted device and the portable device perform transmission / reception. Measure the distance to the aircraft and
Set the accessible area corresponding to the sensor in which the operation by the person is detected,
An electronic key system characterized in that it determines whether or not the position of the portable device exists within the set accessible area based on the distance.
The portable device and the vehicle-mounted device each have a second transmission / reception unit that transmits / receives a second radio wave having a frequency different from that of the first radio wave.
When the control unit of the vehicle-mounted device determines that the position of the portable device based on the distance exists within the set accessible area, the position between the vehicle-mounted device and the portable device is determined. The electronic key system according to claim 1, wherein the vehicle is controlled by transmitting and receiving by the second radio wave.
The electronic key system according to claim 2, wherein the first radio wave has a higher frequency than the second radio wave.
The electronic key system according to any one of claims 1 to 3, wherein the accessible area is set in a different range corresponding to each of the plurality of sensors.
The plurality of sensors according to any one of claims 1 to 4, wherein the plurality of sensors include a door sensor attached to the door handle of the vehicle door and a back door sensor attached to the door handle of the back door of the vehicle. Described electronic key system.