JP2021067056A - Antitheft device, antitheft method, and antitheft system - Google Patents

Abstract

To provide an antitheft device capable of determining illegal unlocking of vehicle door lock with a simple configuration without providing a configuration for preventing unauthorized unlocking on a portable device, and an antitheft method and an antitheft system.SOLUTION: An antitheft device according to an embodiment includes a receiving unit and a determination unit. The receiving unit receives a signal sent from a vehicle when the vehicle door lock is unlocked. The determination unit is configured so as to, when the signal strength of the signal received by the receiving unit is a predetermined level or more, determine that the door lock is illegally unlocked.SELECTED DRAWING: Figure 1C

Description

Disclosure embodiments relate to anti-theft devices, anti-theft methods, and anti-theft systems.

In recent years, there is a method called a relay attack as a method of illegally unlocking a vehicle door lock. In a relay attack, a third party illegally relays a signal transmitted from the vehicle to unlock the door lock of the vehicle and sends it to a smart key in a remote place that should not be reachable. A response signal for unlocking is transmitted from the smart key to illegally unlock the door lock.

For this reason, signals are transmitted by changing the output order for each operation from antennas arranged at a plurality of positions of the vehicle, and the intensity value sequence of the transmitted signal and the intensity of the signal returned from the portable device of the vehicle owned by the vehicle. There is a technique for unlocking when the order of change with the value sequence is consistent (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2016-035133

However, in the above-mentioned conventional technique, it is necessary to provide both the on-board unit and the portable device with a configuration for preventing unauthorized unlocking.

One aspect of the embodiment is made in view of the above, and determines the unauthorized unlocking of the door lock of the vehicle with a simple configuration without providing the portable device with a configuration for preventing unauthorized unlocking. It is intended to provide anti-theft devices, anti-theft methods, and anti-theft systems that can be used.

The anti-theft device according to one aspect of the embodiment includes a receiving unit and a determining unit. The receiving unit receives a signal transmitted from the vehicle to unlock the door lock of the vehicle. The determination unit determines that the door lock is illegally unlocked when the signal strength of the signal received by the reception unit is equal to or higher than a predetermined level.

The anti-theft device, the anti-theft method, and the anti-theft system according to one embodiment of the embodiment have a simple configuration for illegally unlocking the door lock of the vehicle without providing a configuration for preventing unauthorized unlocking of the portable device. Can be determined.

FIG. 1A is an explanatory diagram showing a normal unlocking procedure according to the embodiment. FIG. 1B is an explanatory diagram of a general unauthorized unlocking prevention function according to the embodiment. FIG. 1C is an explanatory diagram showing an outline of the anti-theft method according to the embodiment. FIG. 2 is a block diagram showing a configuration of the anti-theft system according to the embodiment. FIG. 3A is an operation explanatory view of the determination unit according to the embodiment. FIG. 3B is an operation explanatory view of the determination unit according to the embodiment. FIG. 4 is an operation explanatory view of the determination unit according to the embodiment. FIG. 5 is an operation explanatory view of the determination unit according to the embodiment. FIG. 6 is an operation explanatory view of the command unit and the notification unit according to the embodiment. FIG. 7 is a flowchart showing an example of processing executed by the control unit of the anti-theft device according to the embodiment.

Hereinafter, embodiments of the anti-theft device, the anti-theft method, and the anti-theft system will be described in detail with reference to the accompanying drawings. The present invention is not limited to the embodiments shown below.

First, the theft prevention method according to the embodiment will be described with reference to FIGS. 1A to 1C. FIG. 1A is an explanatory diagram showing a normal unlocking procedure according to the embodiment. FIG. 1B is an explanatory diagram of a general unauthorized unlocking prevention function according to the embodiment. FIG. 1C is an explanatory diagram showing an outline of the anti-theft method according to the embodiment.

As shown in FIG. 1A, in the vehicle 100 in recent years, for example, if the owner of the vehicle 100 possesses the smart key 101, the smart key 101 can be operated only by touching the door knob of the vehicle 100 or the like. Also provided is an unlocking system that unlocks the door lock of the vehicle 100.

In the unlocking system, for example, when the owner of the vehicle 100 possessing the smart key 101 touches the door knob of the vehicle, the unlocking device mounted on the vehicle 100 unlocks the door lock of the vehicle 100. A signal (hereinafter referred to as "downlink signal DL") is transmitted.

The unlocking device is designed so that the downlink signal DL can reach only a predetermined distance (for example, a maximum of 3 m). When the smart key 101 receives the downlink signal DL, it transmits a signal (hereinafter, referred to as "uplink signal UP") including an ID indicating that the smart key 101 is the vehicle 100 as a response.

When the unlocking device receives the uplink signal UP transmitted from the smart key 101, the unlocking device unlocks the door lock. Thereby, in the unlocking system, the owner of the vehicle 100 can unlock the door lock by simply touching the door knob of the vehicle, for example.

The smart key 101 is farther than the downlink signal DL (for example, up to 50 m) so that the owner can unlock and lock the door lock of the vehicle 100 from a remote location by operating the smart key 101. Designed to reach up to.

Further, the unlocking device also transmits a downlink signal DL even when, for example, a third party who does not have the smart key 101 touches the door knob of the vehicle 100. However, as shown in FIG. 1B, if the smart key 101 is, for example, more than 3 m, that is, if the owner of the vehicle 100 is not near the vehicle 100, the downlink signal DL will be sent to the smart key 101. Not reach.

Therefore, the smart key 101 does not transmit the uplink signal UP. As a result, the unlocking device does not unlock the door lock even if a third party who does not have the smart key 101 touches the door knob of the vehicle 100.

However, there is known a technique called a relay attack that illegally unlocks the door lock of the vehicle 100 by abusing the above-mentioned unlocking system. For the relay attack, an amplification device 102 that illegally amplifies radio waves is used.

Specifically, as shown in FIG. 1C, a third party performing a relay attack touches the doorknob of the vehicle 100 to transmit a downlink signal DL from the unlocking device, and the downlink signal is transmitted by the illegal amplification device 102. The DL is amplified (step S1).

As a result, the third party can receive the illegally amplified downlink signal DLa to the smart key 101 at a remote location that should not be reachable, and transmit the uplink signal UP from the smart key 101. it can. Then, when the unlocking device receives the illegally transmitted uplink signal UP, the unlocking device unlocks the door lock of the vehicle 100.

Therefore, the anti-theft device according to the embodiment is provided in the vehicle 100 and receives the downlink signal DL transmitted from the unlocking device of the vehicle 100. Then, when the anti-theft device receives a downlink signal DLa whose signal strength is equal to or higher than a predetermined level (step S2), which is not transmitted from the unlocking device, the anti-theft device determines that unauthorized unlocking is performed (step). S3).

As described above, the anti-theft device according to the embodiment has a simple configuration for the door lock of the vehicle 100 even if the portable device such as the smart key 101 is not provided with a configuration for preventing unauthorized unlocking. Unauthorized unlocking can be determined.

As a result, when the anti-theft device determines that the illegal unlocking is performed, for example, the vehicle 100 issues an alarm or notifies the owner of the vehicle 100 that the illegal unlocking is performed. Thereby, the theft of the vehicle 100 can be prevented.

Next, the configuration of the anti-theft device according to the embodiment will be described with reference to FIG. FIG. 2 is a block diagram showing a configuration of the anti-theft system according to the embodiment. As shown in FIG. 2, the anti-theft system 10 according to the embodiment includes an anti-theft device 1, an unlocking device 12, and a drive recorder 13.

The anti-theft system 10 includes an external camera 14, a headlight 15, a horn 16, a portable device (hereinafter, referred to as “terminal 105”) possessed by the owner of the vehicle 100, and a predetermined center device 106. May be further included.

As shown in FIG. 2, the anti-theft device 1 is connected to an antenna 11, an unlocking device 12, a drive recorder 13, an external camera 14, a headlight 15, and a horn 16. Further, the anti-theft device 1 is connected to the terminal 105 and the center device 106 via, for example, a communication network 104 such as the Internet.

The antenna 11 is for receiving the downlink signal DL transmitted from the unlocking device 12 and the downlink signal DLa illegally amplified by the amplification device 102 at the time of relay attack.

For example, when the unlocking device 12 touches the doorknob of the vehicle, the downlink signal DL is transmitted, and when the uplink signal UP transmitted from the smart key 101 is received in response to the downlink signal DL. , A device for unlocking the door lock of the vehicle 100.

When the owner of the vehicle 100 operates the smart key 101 from a remote position where the downlink signal DL does not reach, the unlocking device 12 locks the door of the vehicle 100 in response to a command signal operated from the remote location. Has the function of unlocking and locking.

The drive recorder 13 is, for example, a device that captures images inside and outside the vehicle and stores the captured images. In this embodiment, it is assumed that the drive recorder 13 has a GPS function of receiving radio waves from a GPS (Global Positioning System) satellite to position the vehicle 100.

The drive recorder 13 outputs the position of the vehicle 100 to the anti-theft device 1 when there is a command from the anti-theft device 1. When the drive recorder 13 does not have a GPS function, the anti-theft device 1 is connected to another device having a GPS function, such as a car navigation device, to acquire the position of the vehicle 100.

The external camera 14 is, for example, a camera that images the surroundings of the vehicle 100 and displays it on an in-vehicle display (not shown) when the vehicle 100 is backed up. It is a spherical camera.

The vehicle exterior camera 14 may be an in-vehicle camera that individually captures the front, rear, right side, and left side of the vehicle 100. The headlight 15 is a headlight of the vehicle 100. The horn 16 is a horn that emits a warning sound from the vehicle 100.

The terminal 105 is a device carried by the owner of the vehicle 100, for example, a smartphone. An application program for preventing the theft of the vehicle 100 is installed in the terminal 105 in cooperation with the anti-theft device 1. However, the terminal 105 is not an indispensable configuration requirement for the anti-theft system 10 according to the embodiment.

The center device 106 is a device that supports the theft prevention of a plurality of vehicles 100 equipped with the anti-theft device 1. However, the center device 106 is not an essential configuration requirement for the anti-theft system 10 according to the embodiment. An example of the functions and uses of the terminal 105 and the center device 106 will be described later with reference to FIGS. 5 and 6.

The anti-theft device 1 includes a communication unit 2, a storage unit 3, and a control unit 4. The communication unit 2 is a communication interface that communicates with the unlocking device 12, the drive recorder 13, the external camera 14, the headlight 15, and the horn 16. Further, the communication unit 2 communicates with the terminal 105 and the center device 106 via the communication network 104.

The storage unit 3 is, for example, an information storage device such as a data flash, and stores reception intensity information 31, frequency band information 32, pattern information 33, and distance information 34. The reception strength information 31 is threshold information used for determining whether or not the signal strength of the downlink signal DL is valid.

The frequency band information 32 is information indicating the frequency band of the radio wave used by the unlocking device 12 to transmit the downlink signal DL. The pattern information 33 is information indicating a waveform pattern corresponding to the code of the downlink signal DL. The distance information 34 is information indicating a preset distance between the vehicle 100 and the terminal 105, and is threshold distance information used for determining unauthorized unlocking.

The control unit 4 includes a microcomputer having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and various circuits. The control unit 4 includes a reception unit 41, a determination unit 42, a command unit 43, and a notification unit 44 that function by executing a program stored in the ROM by the CPU using the RAM as a work area. ..

The receiving unit 41, the determination unit 42, the command unit 43, and the notification unit 44 included in the control unit 4 are partially or entirely hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). It may be configured.

The reception unit 41, the determination unit 42, the command unit 43, and the notification unit 44 included in the control unit 4 realize or execute the information processing operations described below, respectively. The internal configuration of the control unit 4 is not limited to the configuration shown in FIG. 2, and may be another configuration as long as it is a configuration for performing information processing described later.

The receiving unit 41 receives the downlink signal DL via the antenna 11 and outputs it to the determination unit 42. The receiving unit 41 acquires the amplitude of the downlink signal DL preset from the unlocking device 12, and stores the amplitude obtained by adding a predetermined margin to the acquired amplitude as the reception strength information 31 which is the determination threshold value for unauthorized unlocking. Store in part 3. Here, an example is shown in which the receiving unit 41 acquires the reception intensity information 31 online from the unlocking device 12 without going through the antenna 11. However, since the amplitude of the downlink signal DL is predetermined, the manufacturer The amplitude obtained by adding a predetermined margin to the amplitude may be stored in the storage unit 3 as the reception intensity information 31 which is the determination threshold for unauthorized unlocking. Alternatively, the anti-theft device 1 may be provided with a setting mode, and the reception strength information 31 may be stored in the storage unit 3 in the setting mode. In this case, the user causes the unlocking device 12 to transmit the downlink signal DL with the anti-theft device 1 in the setting mode. The receiving unit 41 stores the downlink signal DL received via the antenna 11 in the storage unit 3 as reception intensity information 31 based on the amplitude of the downlink signal DL.

The receiving unit 41 acquires information indicating the frequency band of the radio wave used for transmitting the downlink signal DL from the unlocking device 12, and stores it in the storage unit 3 as the frequency band information 32. Here, an example in which the receiving unit 41 receives the frequency band information 32 online from the unlocking device 12 without going through the antenna 11 is shown, but it is set in advance by the manufacturer as in the reception intensity information 31. It may be left as it is, or it may be stored as the frequency band information 32 based on the frequency band of the downlink signal DL received from the unlocking device 12 with the anti-theft device 1 in the setting mode.

For example, when the waveform pattern of the downlink signal DL transmitted by the unlocking device 12 is randomly changed each time, the receiving unit 41 acquires the waveform pattern of the downlink signal DL before transmission from the unlocking device 12 and performs pattern information. It is stored in the storage unit 3 as 33.

The receiving unit 41 acquires threshold distance information, which is information indicating a preset distance between the vehicle 100 and the terminal 105, from the terminal 105, and stores the distance information 34 in the storage unit 3. Here, the threshold distance information is set by the user on the terminal 105, but it may be set by the manufacturer in advance, or the user may set it by any method in the setting mode. Further, the receiving unit 41 acquires the position information of the vehicle 100 from the drive recorder 13, acquires the position information of the terminal 105 from the terminal 105, and outputs the position information to the determination unit 42.

The determination unit 42 invalidates the downlink signal DL received via the antenna 11 based on the downlink signal DL input from the reception unit 41, the reception strength information 31, the frequency band information 32, and the pattern information 33. It is determined whether or not the downlink signal DLa is amplified to. Further, the determination unit 42 calculates the distance between the vehicle 100 and the terminal 105 from the position information of the vehicle 100 input from the reception unit 41 and the position information of the terminal 105.

Here, the determination operation performed by the determination unit 42 will be described with reference to FIGS. 3A to 5. 3A to 5 are operation explanatory views of the determination unit 42 according to the embodiment. The unlocking device 12 always emits a downlink signal DL when, for example, the doorknob of the vehicle 100 is touch-operated, or when a predetermined switch provided near the doorknob is touch-operated, and is always down. Some transmit a link signal DL. Further, the unlocking device 12 transmits a downlink signal DL in which the sequential waveform pattern is arbitrarily changed each time a touch operation is performed.

As shown in FIGS. 3A and 3B, the determination unit 42 compares the amplitude of the received downlink signal DL with the threshold value which is an example of a predetermined level, and determines whether or not the downlink signal DLa is illicitly amplified. To judge. At this time, the determination unit 42 uses the reception intensity information 31 stored in the storage unit 3 as a threshold value.

In the case of the unlocking device 12 that transmits the downlink signal DL for each touch operation, the determination unit 42 has, for example, the amplitude of the downlink signal DL received during the time from time t1 to t2, as shown in FIG. 3A. If it is less than the threshold value, it is determined that the downlink signal DL is valid.

Further, as shown in FIG. 3B, the determination unit 42 amplifies the downlink signal DL by a third party when, for example, the amplitude of the downlink signal DL received during the time from time t11 to t12 is equal to or greater than the threshold value. It is determined that the downlink signal DLa is illegal, and it is determined that the unlocking is performed illegally.

In this way, the determination unit 42 receives the downlink signal DL received by the reception unit 41 based on the amplitude of the downlink signal DL when the door lock stored in the storage unit 3 is properly unlocked. It is determined whether or not the signal strength is equal to or higher than a predetermined level.

As a result, the determination unit 42 only compares the amplitude of the received downlink signal DL with the threshold value, for example, even if the smart key 101 and the terminal 105 are not provided with a configuration for preventing unauthorized unlocking. Therefore, it can be determined that an illegal unlocking is performed.

Further, when the receiving unit 41 receives a signal in a frequency band that matches the frequency band information 32 stored in the storage unit 3, the determination unit 42 determines that the signal strength of the signal received by the receiving unit 41 is at a predetermined level. It is determined whether or not it is the above.

Therefore, the determination unit 42 determines that even if the reception unit 41 receives a signal of a predetermined level or higher, if the frequency band of the signal does not match the frequency band information 32, an illegal unlocking is performed. do not. As a result, the determination unit 42 prevents erroneous determination that unauthorized unlocking is performed when a signal of a predetermined level or higher such as an illegal radio wave that is not a downlink signal DL is received. Can be done.

Further, for example, in the case of the unlocking device 12 that transmits a downlink signal DL in which the sequential waveform pattern is arbitrarily changed each time a touch operation is performed, the determination unit 42 stores the pattern information 33 stored in the storage unit 3. Based on this, it is determined whether or not the downlink signal DLa is invalid.

Specifically, when the receiving unit 41 receives a signal having the same pattern as the pattern stored in the storage unit 3, the determination unit 42 determines that the signal strength of the signal received by the receiving unit 41 is equal to or higher than a predetermined level. Determine if it exists.

As a result, the determination unit 42 can accurately determine that unauthorized unlocking is performed even when the waveform pattern of the downlink signal DL is changed by the unlocking device 12 for each touch operation. ..

Further, as shown in FIG. 4, when the downlink signal DL is constantly transmitted from the unlocking device 12, the determination unit 42 determines that, for example, the amplitude of the downlink signal DL received at times t21 to t22 is a threshold value. If it exceeds, it is determined that the downlink signal DL is an invalid downlink signal DLa amplified by a third party. As a result, the determination unit 42 can accurately determine that unauthorized unlocking is performed even when the downlink signal DL is constantly transmitted from the unlocking device 12.

Further, the determination unit 42 determines from the vehicle 100 based on the position information of the vehicle 100 acquired from the drive recorder 13 and the position information of the terminal 105 acquired from the terminal 105 after determining that the unauthorized unlocking is performed. Calculate the distance to the terminal 105.

Then, the determination unit 42 determines that the illegal unlocking has been performed, for example, when the distance calculated at the time of starting the vehicle 100 is equal to or greater than the predetermined distance stored as the distance information 34 in the storage unit 3. For example, as shown in FIG. 5, it is assumed that the predetermined distance set by the owner of the vehicle 100 as the distance information 34 is 10 m, and the distance from the vehicle 100 to the terminal 105 at this time is 30 m.

In this case, the owner of the vehicle 100 is likely to be at a location 30 m away from the vehicle and is unlikely to be inside the vehicle 100. In such a situation, when the vehicle 100 is started, it is highly possible that the vehicle 100 is started by, for example, a third party who has performed a relay attack.

Therefore, the determination unit 42 determines that the illegal unlocking has been performed when the vehicle 100 is started in the situation shown in FIG. As a result, the determination unit 42 can reliably determine that the illegal unlocking has been performed. When the determination unit 42 determines that an illegal unlocking has been performed or an illegal unlocking has been performed, the determination unit 42 outputs the determination result to the command unit 43 and the notification unit 44.

Here, the operations of the command unit 43 and the notification unit 44 will be described with reference to FIG. FIG. 6 is an operation explanatory view of the command unit 43 and the notification unit 44 according to the embodiment. The command unit 43 commands the drive recorder 13 and the external camera 14 to start imaging when the determination unit 42 inputs a determination result that the lock is illegally unlocked or that the lock is illegally unlocked. Is output.

As a result, as shown in FIG. 6, the drive recorder 13 and the external camera 14 are turned on, and imaging is started and recorded. In this way, the anti-theft device 1 can capture an image of the situation in which the relay attack has been performed by the drive recorder 13 and the external camera 14. Since the drive recorder 13 has a recording function, the recorded image can be saved as evidence of a relay attack.

Further, the command unit 43 issues a command to the headlight 15 and the horn 16 to start an alarm when it is determined that the lock is illegally unlocked or the lock is illegally unlocked. The headlight 15 is turned on according to a command from the command unit 43, and for example, by blinking, it is possible to notify the surroundings of the vehicle 100 that a relay attack has been performed.

Further, the horn 16 is turned on according to a command from the command unit 43, and for example, by intermittently sounding a warning whistle, a third party who has performed a relay attack can be kept away from the vehicle 100. In this way, the headlight 15 and the horn 16 function as an alarm device when an unauthorized unlocking is performed.

Further, the command unit 43 positions the vehicle 100 with respect to the drive recorder 13 when a determination result indicating that the lock has been illegally unlocked or that the lock has been illegally unlocked is input from the determination unit 42. A command is given to transmit the image information 110 of the recorded image to which the information is added to the center device 106. The command unit 43 can also issue a command to transmit the image information captured by the external camera 14 to the center device 106 in real time.

Thereby, for example, the center device 106 can track the vehicle 100 based on the position information and the recorded image of the vehicle 100 included in the image information 110 transmitted from the vehicle 100 stolen after the relay attack.

When the determination unit 42 inputs the determination result that the unauthorized unlocking has been performed or the unauthorized unlocking has been performed, the notification unit 44 transmits information 111 indicating that fact to the terminal 105. Notify the owner of vehicle 100. As a result, the owner of the vehicle can immediately know that the door lock of the vehicle 100 owned by the vehicle has been illegally unlocked or illegally unlocked.

Next, with reference to FIG. 7, a process executed by the control unit 4 of the anti-theft device 1 will be described. FIG. 7 is a flowchart showing an example of processing executed by the control unit 4 of the anti-theft device 1 according to the embodiment. The control unit 4 repeatedly executes the process shown in FIG. 7 at a predetermined cycle by using the standby power during the period when the main power supply of the vehicle 100 is turned off.

Specifically, as shown in FIG. 4, when the main power supply is turned off, the control unit 4 first determines whether or not the downlink signal DL has been received (step S101). Then, when the control unit 4 determines that the downlink signal DL is not received (steps S101, No), the control unit 4 ends the process and starts the process again from step S101.

Further, when the control unit 4 determines that the downlink signal DL has been received (step S101, Yes), the control unit 4 determines whether or not the signal strength of the downlink signal DL is equal to or higher than a predetermined level (threshold value) (step S102). ). Then, when the control unit 4 determines that the signal strength is not equal to or higher than a predetermined level (threshold value) (steps S102, No), the control unit 4 determines whether or not the uplink signal UP has been received (step S111).

Then, when the control unit 4 determines that the uplink signal UP is not received (steps S111, No), the control unit 4 ends the process and starts the process again from step S101. Further, when the control unit 4 determines that the uplink signal UP has been received (steps S111, Yes), the control unit 4 shifts the process to step S107.

Further, in step S102, when the control unit 4 determines that the signal strength is equal to or higher than a predetermined level (steps S102, Yes), it determines that an illegal unlocking is performed (step S103), and images are taken by the vehicle-mounted camera. Start (step S104).

The in-vehicle camera here includes a camera included in the drive recorder 13 shown in FIG. 2 and an external camera 14. The drive recorder 13 records the captured image and outputs the recorded image to the anti-theft device 1. The external camera 14 outputs the captured image to the anti-theft device 1.

Subsequently, the control unit 4 notifies the owner of the vehicle 100 that the door lock of the vehicle 100 is illegally unlocked (step S105), and then determines whether or not the vehicle 100 has been activated (step). S106). Then, when the control unit 4 determines that the vehicle 100 is not started (step S106), the control unit 4 repeats the determination process of step S106.

Further, when the control unit 4 determines that the vehicle 100 has been started (step S106, Yes), the control unit 4 calculates the distance between the vehicle 100 and the terminal 105, and determines whether or not the distance is equal to or greater than a predetermined distance (step S107). .. Then, when the control unit 4 determines that the distance is not equal to or greater than a predetermined distance (steps S107, No), the control unit 4 ends the process and starts the process again from step S101.

Further, when the control unit 4 determines that the distance is equal to or greater than a predetermined distance (step S107, Yes), it determines that an illegal unlocking has been performed (step S108), and causes an alarm by an alarm device. The alarm device here includes the headlight 15 and the horn 16 shown in FIG.

When the drive recorder 13 functions as an alarm device, for example, the drive recorder 13 blinks an LED (Light Emitting Diode) indicating that recording is in progress. The alarm device may include a drive recorder 13.

After that, the control unit 4 transmits the image captured by the drive recorder 13 and the vehicle exterior camera 14 and the position of the vehicle 100 to the center device 106 (step S110), and ends the process.

The above-described embodiment is an example, and various modifications are possible. For example, the function provided in the anti-theft device 1 shown in FIG. 2 may be mounted on the drive recorder 13. Further, in the process shown in FIG. 7, when it is determined that the unlocking is performed illegally (step S103), the in-vehicle camera starts imaging (step S104) and notifies the owner of the vehicle 100 (step S105). However, when it is determined that the unlocking has been performed improperly (step S108), steps S104 and S105 may be performed.

Further, the alarm by the alarm device (step S109) and the process of transmitting the captured image and the position of the vehicle 100 to the center device 106 (step S110) are performed when it is determined that an illegal unlocking is performed (step S103). ) May be used.

Further effects and variations can be easily derived by those skilled in the art. For this reason, the broader aspects of the invention are not limited to the particular details and representative embodiments expressed and described as described above. Therefore, various modifications can be made without departing from the spirit or scope of the general concept of the invention as defined by the appended claims and their equivalents.

1 Anti-theft device 2 Communication unit 3 Storage unit 31 Reception strength information 32 Frequency band information 33 Pattern information 34 Distance information 4 Control unit 41 Reception unit 42 Judgment unit 43 Command unit 44 Notification unit 10 Anti-theft system 11 Antenna 12 Unlocking device 13 Drive recorder 14 Outside camera 15 Headlight 16 Claction 100 Vehicle 101 Smart key 102 Amplifier 104 Communication network 105 Terminal 106 Center device

Claims (11)

A receiver that receives a signal transmitted from the vehicle to unlock the door lock of the vehicle,
An anti-theft device comprising: a determination unit for determining that an unauthorized unlocking of the door lock is performed when the signal strength of the signal received by the receiving unit is equal to or higher than a predetermined level. A storage unit for storing the amplitude of the signal when the door lock is properly unlocked is provided.
The determination unit
The anti-theft device according to claim 1, wherein it is determined whether or not the signal strength of the signal received by the receiving unit is equal to or higher than a predetermined level based on the amplitude stored in the storage unit. .. A storage unit for storing a predetermined frequency band of the signal transmitted from the vehicle is provided.
The determination unit
When a signal in the frequency band stored in the storage unit is received by the receiving unit, it is characterized in that it is determined whether or not the signal strength of the signal received by the receiving unit is equal to or higher than a predetermined level. The anti-theft device according to claim 1 or 2. A storage unit for storing a pattern in which a signal transmitted from the vehicle is sequentially changed is provided.
The determination unit
When a signal of the same pattern as the pattern stored in the storage unit is received by the receiving unit, it is determined whether or not the signal strength of the signal received by the receiving unit is equal to or higher than a predetermined level. The anti-theft device according to any one of claims 1 to 3. The theft according to any one of claims 1 to 4, further comprising a notification unit that notifies the owner of the vehicle when the determination unit determines that the illegal unlocking is performed. Prevention device. It is characterized by including a command unit that gives a command to start imaging to an in-vehicle camera that images the interior and / or surroundings of the vehicle when the determination unit determines that the unauthorized unlocking is performed. The anti-theft device according to any one of claims 1 to 5. The determination unit
The distance from the vehicle to the mobile device is calculated based on the position of the vehicle and the position of the mobile device registered in advance, and when the distance at the time of starting the vehicle is equal to or more than a predetermined distance, the illegality is performed. The anti-theft device according to claim 6, wherein it is determined that the unlocking has been performed. The command unit
The anti-theft device according to claim 7, wherein when the determination unit determines that the unauthorized unlocking has been performed, a command to start an alarm is issued to the alarm device of the vehicle. The command unit
7. Claim 7 or claim, wherein when the determination unit determines that the unauthorized unlocking has been performed, the image captured by the vehicle-mounted camera and the position of the vehicle are transmitted to a predetermined center device. Item 8. The anti-theft device according to item 8. A receiving process for receiving a signal transmitted from the vehicle to unlock the door lock of the vehicle,
A method for preventing theft, which comprises a determination step of determining that an illegal unlocking of the door lock is performed when the signal strength of the signal received by the reception step is equal to or higher than a predetermined level. A drive recorder that captures and records the interior and / or surroundings of the vehicle,
An unlocking device that unlocks the door lock of the vehicle according to remote control,
Including anti-theft device
The anti-theft device is
A receiving unit that receives a signal transmitted from the unlocking device to unlock the door lock of the vehicle, and a receiving unit.
When the signal strength of the signal received by the receiving unit is equal to or higher than a predetermined level, the determination unit that determines that the door lock is illegally unlocked and the determination unit illegally unlocks the door lock. An anti-theft system characterized in that the drive recorder is provided with a command unit for instructing the start of shooting when it is determined that the test has been performed.

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