WO2017043335A1

WO2017043335A1 - Keyless entry device, communication device for keyless entry devices, and control method for keyless entry devices

Info

Publication number: WO2017043335A1
Application number: PCT/JP2016/074947
Authority: WO
Inventors: 宮澤　明
Original assignee: アルプス電気株式会社
Priority date: 2015-09-10
Filing date: 2016-08-26
Publication date: 2017-03-16

Abstract

Provided is a keyless entry device with a simple configuration that can prevent fraud quickly and precisely. A first communication device 200 comprises a low frequency (LF) transmission unit 210 to wirelessly transmit a composite authentication signal having a plurality of authentication signals that use sine waves of varying frequencies as carrier waves. A second communication device 300 comprises a LF reception unit 310 to receive the composite authentication signal. Both the first communication device 200 and the second communication device 300 further comprise a processing unit 250 and a processing unit 330, respectively. The processing unit 250 and the processing unit 330 perform processing for proper events when the waveform of the composite authentication signal received by the LF reception unit 310 of the second communication device 300 satisfies prescribed conditions and perform processing for improper events when the waveform of the composite authentication signal received by the LF reception unit 310 of the second communication device 300 does not satisfy prescribed conditions.

Description

Keyless entry device, communication device for keyless entry device, and control method for keyless entry device

The present invention relates to a keyless entry device, a communication device for a keyless entry device, and a control method for the keyless entry device.

Wireless communication between the in-vehicle device mounted on the vehicle and the portable device carried by the driver unlocks the door of the vehicle when it is confirmed that the portable device is within a certain range from the vehicle. There is a keyless entry device that performs processing such as locking.

The conventional keyless entry device uses an LF (low frequency) signal for wireless communication from the in-vehicle device to the portable device, and uses an RF (radio frequency) signal for wireless communication from the portable device to the on-vehicle device. is there. In wireless communication using an LF signal, communication is sufficiently possible at a distance of about several meters, but communication is difficult at a distance farther than that. The carrier wave of the LF signal is a sine wave of several hundred kHz, for example. In wireless communication using RF signals, normal communication can be performed over a distance of several tens of meters to several hundreds of meters. The carrier wave of the RF signal is, for example, a sine wave of 426 MHz to 429 MHz.

For example, when the distance between the vehicle and the portable device is within the receivable range of the LF signal, the in-vehicle device permits the vehicle control unit to unlock the door based on the response from the portable device. On the other hand, when the portable device is away from the receivable range of the LF signal transmitted from the in-vehicle device, normally, the response from the portable device does not return to the in-vehicle device, so that the unlocking of the door is not permitted.

However, the first unauthorized repeater intercepts the LF signal near the vehicle-mounted device, transmits the waveform information of the LF signal as an RF signal, and the second unauthorized repeater transmits the LF signal from the RF signal near the portable device. A relay attack that reproduces and transmits is known. When a relay attack is performed, the LF signal transmitted from the in-vehicle device reaches a portable device that is farther than the receivable range of the LF signal. Then, since the portable device is mistakenly recognized as being near the vehicle-mounted device and returns a normal response to the vehicle-mounted device, there is a problem that the vehicle-mounted device permits the unlocking of the vehicle door.

As disclosed in Patent Document 1, a keyless entry device that changes the intensity of an LF signal transmitted from an in-vehicle device is known. Unauthorized repeaters with poor performance often cannot reproduce changes in the strength of the LF signal. Therefore, by detecting the change in the strength of the LF signal with a portable device, the presence or absence of a relay attack can be detected to prevent fraud. Can do.

In the wireless key system disclosed in Patent Document 2, the frequency of the carrier wave of the signal transmitted from the vehicle-mounted device is one at each time point, but changes with time. The changed frequency is notified in advance between the in-vehicle device and the portable device. An unauthorized repeater with poor performance often cannot follow a frequency that changes over time, so it can detect the presence or absence of a relay attack by measuring the signal strength of the frequency corresponding to each time point with a portable device. Fraud can be prevented.

JP 2010-185186 A JP2008-240315

However, since an unauthorized repeater that can reproduce the change in the intensity of the LF signal has recently appeared, there is a disadvantage that the keyless entry device of Patent Document 1 may not be able to detect the presence or absence of a relay attack.

The wireless key system disclosed in Patent Document 2 has a disadvantage that it takes a long time to discriminate because the device is complicated because notification of the frequency to be used is required and the signal strength needs to be measured a plurality of times.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a keyless entry device, a communication device for the keyless entry device, and a control method for the keyless entry device that can prevent fraud with a simple configuration with high accuracy in a short time. It is to provide.

The present invention includes a first communication device and a second communication device that perform wireless communication, and performs appropriate time processing when wireless communication is appropriate and incorrect time processing when wireless communication is inappropriate. A keyless entry device, wherein the first communication device includes a transmitter that wirelessly transmits a composite authentication signal having a plurality of authentication signals having sine waves of different frequencies as carrier waves, and the second communication device is configured to A receiving unit that receives the authentication signal, at least one of the first communication device and the second communication device further includes a processing unit, and the processing unit is received by the receiving unit of the second communication device. Processing is performed when the waveform of the authentication signal satisfies a predetermined condition, and processing is performed when the waveform of the combined authentication signal received by the receiving unit of the second communication apparatus does not satisfy the predetermined condition. It is a keyless entry device.

According to this configuration, fraud can be prevented with a simple configuration with high accuracy in a short time. In particular, it is possible to prevent fraud by an unauthorized repeater that cannot reproduce a combined wave obtained by combining signals of a plurality of frequencies transmitted simultaneously.

Preferably, in the keyless entry device of the present invention, the transmission unit of the first communication device includes a first sub-transmission unit that transmits at least one of the plurality of authentication signals from the first position, and a plurality of A second sub-transmission unit that transmits at least one other authentication signal from the second position different from the first position.

According to this configuration, fraud can be prevented with a simple configuration with high accuracy in a short time. In particular, by transmitting signals of a plurality of frequencies simultaneously from a plurality of positions, reproduction by an unauthorized repeater can be made difficult.

Preferably, in the keyless entry device of the present invention, the processing unit has a predetermined authentication signal waveform of at least one of the plurality of authentication signals in the combined authentication signal received by the receiving unit of the second communication device. When the condition of the above condition is satisfied, the process is performed at the appropriate time, and when the waveform of the predetermined authentication signal does not satisfy the predetermined condition in the composite authentication signal received by the receiving unit of the second communication device, the process at the inappropriate time is performed. .

According to this configuration, fraud can be prevented with a simple configuration with high accuracy in a short time. In particular, fraud can be prevented by switching processing according to the waveform of the synthesized wave.

Preferably, in the keyless entry device according to the present invention, when the processing unit has a beat in the synthesized authentication signal received by the receiving unit of the second communication device, the processing is performed when appropriate, and the reception of the second communication device is performed. When there is no beat in the composite authentication signal received by the unit, processing is performed when it is inappropriate.

According to this configuration, fraud can be prevented with a simple configuration with high accuracy in a short time. In particular, by switching processing according to the swell of the composite wave, it is possible to prevent cheating by an unauthorized repeater that cannot reproduce the swell.

Preferably, in the keyless entry device of the present invention, the appropriate time process includes continuing communication between the first communication device and the second communication device, and the incorrect time process is performed with the first communication device and the first communication device. Including stopping communication with the second communication device.

According to this configuration, fraud can be prevented with a simple configuration with high accuracy in a short time. In particular, it is possible to prevent timely processing when there is a fraud.

Preferably, in the keyless entry device according to the present invention, the second communication device further includes a transmission unit, and the appropriate time processing indicates that wireless communication between the first communication device and the second communication device is appropriate. Information indicating that the wireless communication between the first communication device and the second communication device is inappropriate, including transmission of information indicating from the transmission unit of the second communication device. And transmitting from the transmission unit of the second communication device.

According to this configuration, fraud can be prevented with a simple configuration with high accuracy in a short time. In particular, it is possible to clearly execute the inappropriate process by explicitly indicating that the wireless communication is inappropriate.

Preferably, in the keyless entry device of the present invention, the second communication device transmits information on the waveform of the composite authentication signal received by the transmission unit and the reception unit of the second communication device from the transmission unit of the second communication device. A first communication device further including a receiving unit that receives information from the transfer unit of the second communication device, and at least a part of the processing unit. At least a part of the processing unit included in the device performs appropriate time processing and inappropriate time processing based on information received by the first communication device.

According to this configuration, fraud can be prevented with a simple configuration with high accuracy in a short time. In particular, it is possible to prevent fraud by an unauthorized repeater that cannot reproduce a composite wave obtained by combining signals of a plurality of frequencies.

Preferably, the communication device for a keyless entry device of the present invention wirelessly communicates with another communication device, and processing when the wireless communication is appropriate and processing when the wireless communication is inappropriate Is a communication device for a keyless entry device that performs in cooperation with other communication devices, and includes a transmission unit that wirelessly transmits a composite authentication signal having a plurality of authentication signals with sine waves of different frequencies as carrier waves, In combination with the communication device, when the waveform of the composite authentication signal received by the reception unit of the other communication device satisfies a predetermined condition, the composite authentication is performed at the appropriate time and received by the reception unit of the other communication device. When the waveform of the signal does not satisfy a predetermined condition, processing is performed when it is inappropriate.

Preferably, the communication device for a keyless entry device of the present invention wirelessly communicates with another communication device, and processing when the wireless communication is appropriate and processing when the wireless communication is inappropriate A communication unit for a keyless entry device, which is performed in cooperation with another communication device, and a receiving unit that receives a composite authentication signal having a plurality of authentication signals with sine waves of different frequencies as carrier waves from the other communication device. And, when the waveform of the composite authentication signal received by the receiving unit satisfies a predetermined condition in cooperation with another communication device, processing is performed when appropriate, and the waveform of the composite authentication signal received by the receiving unit is predetermined If the condition is not met, process when inappropriate.

Preferably, the control method of the keyless entry device of the present invention is the improper processing when the wireless communication between the first communication device and the second communication device is appropriate and the improper processing when the wireless communication is inappropriate. A keyless entry device control method for performing time processing, wherein a first communication device wirelessly transmits a composite authentication signal having a plurality of authentication signals having sine waves of different frequencies as carrier waves; When the composite authentication signal is received by the communication device, and when the waveform of the composite authentication signal received by the second communication device satisfies a predetermined condition, the processing is performed at an appropriate time and received by the second communication device. When the waveform of the combined authentication signal does not satisfy a predetermined condition, processing is performed when it is inappropriate.

According to the keyless entry device, the communication device for the keyless entry device, and the control method for the keyless entry device of the present invention, fraud can be prevented with a simple configuration with high accuracy in a short time.

It is a block diagram of the keyless entry apparatus of embodiment of this invention. It is the schematic of the vehicle carrying the keyless entry apparatus shown in FIG. It is a partial waveform diagram of the carrier wave of the first LF signal. It is a wave form diagram of the 1st LF signal. It is a partial waveform diagram of the carrier wave of the second LF signal. It is a wave form diagram of the 2nd LF signal. It is a partial waveform figure of a synthetic authentication signal. It is a flowchart of the control method of the keyless entry apparatus shown in FIG. It is a figure for demonstrating operation | movement of the keyless entry apparatus shown in FIG. 1 when a fraudulent act is performed. It is a block diagram of the 2nd communication apparatus which concerns on the modification of embodiment of this invention.

Hereinafter, the keyless entry device 100 according to the embodiment of the present invention will be described. As shown in FIG. 1, the keyless entry device 100 includes a first communication device 200 (on-vehicle device) and a second communication device 300 (mobile device). As shown in FIG. 2, the first communication device 200 is mounted on a vehicle 400. The second communication device 300 is movable and is carried by a driver inside and outside the vehicle 400, for example. The first communication device 200 determines whether the second communication device 300 exists near the vehicle 400 using wireless communication with the second communication device 300, and locks the door of the vehicle 400, for example. And unlocking.

As shown in FIG. 1, the first communication device 200 includes an LF transmission unit 210, an RF reception unit 240, a processing unit 250, and a storage unit 260.

The LF transmission unit 210 includes a first LF sub transmission unit 220 and a second LF sub transmission unit 230.

The first LF sub transmission unit 220 includes a first LF transmission circuit 221 and a first LF transmission antenna 222. The first LF transmission circuit 221 generates the exemplary first LF signal 510 shown in FIG. 3B by using the sine wave 501 having the first frequency f1 shown in FIG. 3A as a carrier wave. Transmit through the first LF transmit antenna 222 shown.

The first LF signal 510 shown in FIG. 3B includes an information signal 511, an intensity measurement signal 512, and a first authentication signal 513. The information signal 511 transmits information such as an activation signal and various commands between the first communication device 200 and the second communication device 300 as in the past. The intensity measurement signal 512 transmits a signal for measuring the distance between the first communication device 200 and the second communication device 300 as in the related art. The first authentication signal 513 continues for a predetermined period with a constant maximum intensity.

1 includes a second LF transmission circuit 231 and a second LF transmission antenna 232. The second LF sub transmission unit 230 illustrated in FIG. The second LF transmission circuit 231 generates the exemplary second LF signal 520 shown in FIG. 4B by using the sine wave 502 having the second frequency f2 shown in FIG. 4A as a carrier wave. Transmit through the second LF transmit antenna 232 shown.

4B includes a second authentication signal 521. The second LF signal 520 illustrated in FIG. The second authentication signal 521 continues for a predetermined period with a constant maximum intensity. The first authentication signal 513 illustrated in FIG. 3B and the second authentication signal 521 illustrated in FIG. 4B are transmitted at the same timing over at least a part of the period.

The first LF transmission antenna 222 and the second LF transmission antenna 232 are mounted at different positions of the vehicle 400 shown in FIG. The first LF transmission antenna 222 and the second LF transmission antenna 232 are not limited to these. For example, the first position 401 between the driver's seat and the passenger seat, the second LF in the door at the rear of the vehicle. It is mounted at any of the position 402, the third position 403 in the rear right door, and the fourth position 404 in the rear left door.

The combined signal of the first authentication signal 513 (FIG. 3B) and the second authentication signal 521 (FIG. 4B) is referred to as a combined authentication signal. When the first authentication signal 513 (FIG. 3B) and the second authentication signal 521 (FIG. 4B) are transmitted at the same timing and properly received, as shown in FIG. 4C, the combined authentication signal 531 A beat 532 is generated. The beat 532 occurs in a time range in which the first authentication signal 513 (FIG. 3B) and the second authentication signal 521 (FIG. 4B) are received simultaneously. The frequency of the beat 532 is equal to the difference between the first frequency f1 and the second frequency f2. In the present embodiment, the second frequency f2 is smaller than the first frequency f1 and is close to the first frequency f1 to the extent that a beat is generated. Note that the second frequency f2 may be greater than the first frequency f1.

As shown in FIG. 1, the RF receiving unit 240 includes an RF receiving circuit 241 and an RF receiving antenna 242. The RF receiving circuit 241 receives an RF signal through the RF receiving antenna 242 and reads information from the received RF signal. The RF receiver 240 is mounted at an appropriate position (not shown) of the vehicle 400 shown in FIG.

1 is, for example, a central processing unit. The storage unit 260 is, for example, a random access memory. The processing unit 250 reads the program stored in the storage unit 260 and executes various processes. The processing unit 250 cooperates with the processing unit 330 of the second communication device 300 to perform appropriate time processing when wireless communication is appropriate and inappropriate time processing when wireless communication is inappropriate. Specifically, the processing unit 250 instructs the first LF transmission circuit 221 and the second LF transmission circuit 231 to send the first LF signal 510 (FIG. 3B) and the second LF signal 520 (FIG. 4B). ) Is generated. Further, the processing unit 250 receives information in the RF signal from the RF receiving circuit 241. Details of the operation of the processing unit 250 will be described later.

The second communication apparatus 300 includes an LF receiving unit 310, an RF transmitting unit 320, a processing unit 330, and a storage unit 340.

The LF reception unit 310 includes an LF reception circuit 311 and an LF reception antenna 312. The LF reception circuit 311 transmits the first LF signal 510 (FIG. 3B), the second LF signal 520 (FIG. 4B), the first LF signal 510 (FIG. 3B), and the second LF signal via the LF reception antenna 312. A composite authentication signal 531 (FIG. 4C), which is a composite signal with the LF signal 520 (FIG. 4B), is received.

The LF reception circuit 311 receives the information signal 511 (FIG. 3B) and the intensity measurement signal 512 (FIG. 3B) at the first frequency f1 as in the conventional case. Further, the LF reception circuit 311 combines the first authentication signal 513 (FIG. 3B) with the first frequency f1 and the second authentication signal 521 (FIG. 4B) with the second frequency f2 into a combined authentication signal 531. (FIG. 4C) is received.

When fraud is involved, the composite authentication signal received by the LF receiver 310 of the second communication device 300 is not necessarily the same as the composite authentication signal transmitted from the first communication device 200. For convenience, both are referred to as a composite authentication signal.

The RF transmission unit 320 includes an RF transmission circuit 321 and an RF transmission antenna 322. The RF transmission circuit 321 generates an RF signal and transmits the RF signal through the RF transmission antenna 322.

The processing unit 330 is, for example, a central processing unit. The storage unit 340 is, for example, a random access memory. The processing unit 330 reads the program stored in the storage unit 340 and executes various processes. The processing unit 330 cooperates with the processing unit 250 of the first communication device 200 to perform an appropriate time process when wireless communication is appropriate and an incorrect time process when wireless communication is inappropriate. Details of the operation of the processing unit 330 will be described later.

Next, a control method of the keyless entry device 100 according to the present embodiment executed by the processing unit 250 and the processing unit 330 in cooperation with each other will be described with reference to the flow 600 of FIG.

Here, a difference in processing between when the unauthorized relay is interposed in wireless communication between the first communication device 200 and the second communication device 300 and when it is not interposed will be described in detail. In addition, the keyless entry device 100 is executed by a conventional keyless entry device such as measurement of the distance between the first communication device 200 and the second communication device 300 based on the strength measurement signal 512 (FIG. 3B). Although the above process may be executed, description thereof is omitted.

First, in step 601, the first communication device 200 (on-vehicle device) shown in FIG. 1 is a composite signal that is a composite signal of the first authentication signal 513 (FIG. 3B) and the second authentication signal 521 (FIG. 4B). Send an authentication signal. At least one authentication signal of the composite authentication signal is wirelessly transmitted from each of at least one position. That is, the first authentication signal 513 (FIG. 3B) and the second authentication signal 521 (FIG. 4B) may be transmitted from one position after being combined, and space is transmitted by transmitting from another position. It may be combined with the combined authentication signal.

Specifically, the first LF transmission circuit 221 generates a first authentication signal 513 (FIG. 3B) according to an instruction from the processing unit 250 of the first communication device 200, and the first LF transmission antenna 222 receives the first authentication signal 513. Send. Further, according to the instruction of the processing unit 250, the second LF transmission circuit 231 generates the second authentication signal 521 (FIG. 4B) and transmits it from the second LF transmission antenna 232. Transmission timings of the first authentication signal 513 (FIG. 3B) and the second authentication signal 521 (FIG. 4B) at least partially overlap. The timing at which the composite authentication signal is transmitted may be regular or non-periodic.

Next, in step 602, the LF receiver 310 of the second communication device 300 (portable device) shown in FIG.

Next, in step 603, the processing unit 330 of the second communication device 300 determines whether the waveform of the received composite authentication signal satisfies a predetermined condition. In the present embodiment, as shown in FIG. 4C, when the beat 532 is present in the received composite authentication signal 531, it is determined that the waveform of the received composite authentication signal satisfies a predetermined condition.

Specifically, when there is a beat 532 having a frequency equal to the difference between the first frequency f1 and the second frequency f2, it is determined that the waveform of the received composite authentication signal satisfies a predetermined condition. . Even if the frequency of the beat 532 deviates from the difference between the first frequency f1 and the second frequency f2, if the width of the deviation is less than or equal to a predetermined threshold or less than the threshold, the received synthesized authentication signal It is determined that the waveform satisfies a predetermined condition.

The reason for referring to the beat 532 is that, as will be described later, if an unauthorized relay is present in the wireless communication, it is difficult to reproduce the beat, so the presence of the unauthorized relay can be confirmed.

The processing unit 330 of the second communication device 300 samples the composite authentication signal received by the LF receiving unit 310 at a sampling cycle of n × (f1-f2), where n is an integer. This sampling period is the minimum period necessary for detecting beat.

Note that the predetermined condition may be another condition. For example, it is received when the time between local maximum values of the beat 532 of the received composite authentication signal 531, the time between local minimum values, and the time between the local maximum value and the local minimum value are within a predetermined range. It may be determined that the waveform of the combined authentication signal satisfies a predetermined condition.

For example, on the basis of either the maximum value or the minimum value of the beat 532 of the received composite authentication signal 531, the ratio between the reception strength and the maximum value of the composite authentication signal 531 after n times the sampling period is predetermined. When it is within the range, it may be determined that the waveform of the received composite authentication signal satisfies a predetermined condition.

When the first authentication signal 513 (FIG. 3B) and the second authentication signal 521 (FIG. 4B), which are components of the composite authentication signal 531, are separately examined, and each is greater than or equal to a predetermined strength or greater than a predetermined strength The waveform of the received composite authentication signal may be determined to satisfy a predetermined condition.

When the waveform satisfies a predetermined condition in the determination in step 603, in step 604, when at least one of the first communication device 200 and the second communication device 300 in FIG. Process.

The appropriate time process of the present embodiment includes returning a response from the second communication device 300 to the first communication device 200 as usual. In response to the response, the first communication device 200 transmits a signal permitting locking or unlocking of the door to a control unit (not shown) of the vehicle 400. When the waveform of the received composite authentication signal satisfies a predetermined condition, there is a high possibility that wireless communication between the first communication device 200 and the second communication device 300 shown in FIG. 1 is properly performed. . Therefore, there is a high possibility that the door may be unlocked by continuing conventional communication.

The appropriate time process may be various other processes performed when wireless communication is appropriate. For example, the appropriate time process may include sending information indicating that wireless communication is appropriate from the second communication device 300 to the first communication device 200. In response to this information, for example, the first communication device 200 transmits a signal permitting unlocking or unlocking of the door to the vehicle 400. In the present embodiment, the determination in step 603 is mainly performed by the second communication device 300, but at least a part of the determination in step 603 may be performed by the first communication device 200. When at least a part of the determination in step 603 is performed by the first communication device 200, information related to the waveform of the composite authentication signal is transmitted from the second communication device 300 to the first communication device 200. The information related to the waveform of the composite authentication signal includes, for example, waveform information obtained by sampling the received composite authentication signal, or the maximum intensity of the received composite authentication signal, the period of the predetermined intensity, the frequency, and the like.

If it is determined in step 603 that the waveform does not satisfy a predetermined condition, in step 605, at least one of the first communication device 200 and the second communication device 300 in FIG. Process when inappropriate.

The improper processing in this embodiment includes not returning a response from the second communication device 300 to the first communication device 200. Since the first communication device 200 does not receive a response, the first communication device 200 does not allow the control unit (not shown) of the vehicle 400 to lock or unlock the door. When the waveform of the received composite authentication signal does not satisfy the predetermined condition, there is a possibility that someone is involved in the wireless communication between the first communication device 200 and the second communication device 300 shown in FIG. Is expensive. Therefore, by not performing a response, it is possible to prevent an illegal act such as an undesirable door locking or unlocking by a suspicious person.

The improper processing may be various other processing performed when wireless communication is inappropriate. For example, the improper process may include sending information indicating that the wireless communication is inappropriate from the second communication apparatus 300 to the first communication apparatus 200. In response to this information, the first communication device 200 transmits, for example, an alarm in which a suspicious person is present to a control unit (not shown) of the vehicle 400.

Here, an example of a case where wireless communication between the first communication device 200 (on-vehicle device) and the second communication device 300 (mobile device) is inappropriate will be described with reference to FIG.

The receivable range of the LF signal 711 transmitted from the first communication device 200 is about several meters from the vehicle 400. When the second communication device 300 exists in the receivable range of the LF signal 711 transmitted from the first communication device 200, the second communication device 300 transmits the LF from the first communication device 200. The signal 711 is directly received and a response is returned to the first communication device 200. In this case, since there is a high possibility that a driver is present near the vehicle 400, even if the first communication device 200 performs appropriate processing such as unlocking the door, problems such as theft may not occur. Many.

On the other hand, when the second communication device 300 exists outside the receivable range of the LF signal 711 transmitted from the first communication device 200, if there is no fraud, the second communication device 300 The LF signal 711 from the communication device 200 is not directly received. As a result, no response is returned from the second communication device 300 to the first communication device 200. In this case, since there is a high possibility that the driver is not present near the vehicle 400, the first communication device 200 can prevent theft or the like by not performing appropriate processing such as unlocking the door.

However, even if the second communication device 300 exists outside the receivable range of the LF signal 711 transmitted from the first communication device 200, if there is an injustice, it is transmitted from the first communication device 200. The LF signal 711 may reach the second communication device 300.

Specifically, as shown in FIG. 6, the first unauthorized repeater 701 receives the LF signal 711 transmitted from the first communication device 200 in the vicinity of the first communication device 200. The first unauthorized repeater 701 converts the received LF signal 711 into a relay RF signal 712 and transmits it far away. The second unauthorized repeater 702 receives the relay RF signal 712 in the vicinity of the second communication device 300. The second unauthorized repeater 702 generates and transmits a reproduced LF signal 713 having the same waveform as the LF signal 711 from the received relay RF signal 712.

The conventional first unauthorized repeater 701 and the second unauthorized repeater 702 can cope with radio signals of various frequencies used in various vehicle types by selectively using a single frequency. Many. Accordingly, the conventional first unauthorized repeater 701 and the second unauthorized repeater 702 are good at reproducing the single-frequency reproduction LF signal 713 from the single-frequency LF signal 711, but the multiple frequencies It is not good to reproduce the reproduced LF signal 713 having a plurality of frequencies from the LF signal 711 simultaneously. In general, the first unauthorized repeater 701 and the second unauthorized repeater 702 are often poor in sensitivity, and are close to either the first LF transmission antenna 222 or the second LF transmission antenna 232. May be used. When approaching one of the first LF transmission antenna 222 and the second LF transmission antenna 232, the reception strength of the signal from the closer one becomes strong, but the reception strength of the signal from the other becomes very weak. As a result, the reproduced LF signal 713 has a small change in beat amplitude compared to the case where there is no fraud, or no beat is reproduced at all.

When the LF signal 711 from the first communication device 200 is transmitted with a single frequency carrier wave as in the conventional case, the conventional first unauthorized repeater 701 and the second unauthorized repeater 702 perform the first communication. The LF signal 711 from the apparatus 200 can be easily reproduced as the reproduced LF signal 713. Accordingly, when the second communication device 300 receives the reproduced LF signal 713 that has been illegally reproduced, the second communication device 300 may misunderstand that the first communication device 200 exists nearby and transmit a normal response RF signal 714. . The response RF signal 714 reaches farther than the LF signal 711, and therefore easily reaches the first communication device 200 that is far beyond the receivable range of the LF signal 711. In the related art, the first communication device 200 that has received a normal response from the second communication device 300 may permit the unlocking of the door despite the unauthorized relay.

On the other hand, in the case of the present embodiment, the first communication device 200 uses, as the LF signal 711, a first LF signal 510 having a sine wave of the first frequency f1 as a carrier wave and a sine wave of the first frequency f1. The second LF signal 520 serving as a carrier wave is transmitted at the same timing over at least a part of the period. The conventional first unauthorized repeater 701 and second unauthorized repeater 702 suitable for reproduction of a single frequency can simultaneously reproduce the first LF signal 510 and the second LF signal 520 having different frequencies. difficult. Therefore, the reproduced LF signal 713 reproduced illegally has a weak intensity of either the first LF signal 510 or the second LF signal 520, and the beat 532 shown in FIG. Does not occur.

The first LF transmission antenna 222 and the second LF transmission antenna 232 shown in FIG. 1 are arranged apart from each other at two of the first position 401 to the fourth position 404 as shown in FIG. Has been. When the reception sensitivity of the first unauthorized repeater 701 and the second unauthorized repeater 702 is poor, one of the first LF transmission antenna 222 and the second LF transmission antenna 232 is used to obtain a sufficiently high reception strength. I need to get closer. Then, the reception strength of the other of the first LF transmission antenna 222 and the second LF transmission antenna 232 is lowered.

The conventional first unauthorized repeater 701 and the second unauthorized repeater 702 with poor reception sensitivity may receive the first LF signal 510 and the second LF signal 520 transmitted from different positions with the same strength. difficult. Therefore, the reproduced LF signal 713 reproduced illegally has a weak intensity of either the first LF signal 510 or the second LF signal 520, and the beat 532 shown in FIG. Does not occur. Therefore, it can be detected that the reproduction LF signal 713 is illegally reproduced.

When the received composite authentication signal is an illegally reproduced LF signal 713, the second communication device 300 responds to the first communication device 200 because the waveform of the composite authentication signal does not satisfy a predetermined condition. The RF signal 714 is not returned. Therefore, it is possible to prevent an illegal act such as an undesirable door locking or unlocking by a suspicious person.

According to the keyless entry device 100 of this embodiment, fraud can be prevented with a simple configuration with high accuracy in a short time. In particular, it is possible to prevent fraud by an unauthorized repeater that cannot reproduce a combined wave obtained by combining signals of a plurality of frequencies transmitted simultaneously. Further, by simultaneously transmitting signals having a plurality of frequencies from a plurality of positions, reproduction by an unauthorized repeater can be made difficult. Further, fraud can be prevented by switching the processing according to the waveform of the synthesized wave. Further, by switching processing according to the swell of the composite wave, it is possible to prevent cheating by an unauthorized repeater that cannot reproduce the swell. In addition, when there is a fraud, it is possible to prevent the timely processing. Further, by explicitly indicating that wireless communication is inappropriate, it is possible to clearly execute the process when inappropriate.

FIG. 7 is a configuration diagram of the second communication device 800 according to a modification of the present invention. The second communication device 800 of the modification has the same configuration as the second communication device 300 of FIG. 1, but includes a processing unit 830 instead of the processing unit 330. The processing unit 830 functions as the transfer unit 831 by executing a program stored in the storage unit 340. The transfer unit 831 transmits information related to the waveform of the composite authentication signal received by the LF reception unit 310 from the RF transmission unit 320. Specifically, the transfer unit 831 transmits the digital information of the sampled composite authentication signal. The transfer unit 831 may transmit other information related to the composite authentication signal.

The processing unit 250 of the first communication device 200 in FIG. 1 has a predetermined waveform of the composite authentication signal received by the second communication device 800 based on information transmitted from the second communication device 800 of the modification. It is determined whether or not the condition is satisfied. That is, at least a part of the determination described in the keyless entry device 100 of FIG. 1 is performed by the first communication device 200. The information related to the waveform of the composite authentication signal includes, for example, waveform information obtained by sampling the received composite authentication signal, or the maximum intensity of the received composite authentication signal, the period of the predetermined intensity, the frequency, and the like.

According to the keyless entry device of this modification, in addition to the effect of the keyless entry device 100 of FIG. 1, the configuration of the second communication device 300 can be simplified.

The present invention is not limited to the embodiment described above. That is, those skilled in the art may make various changes, combinations, sub-combinations, and alternatives regarding the components of the above-described embodiments within the technical scope of the present invention or an equivalent scope thereof.

The present invention can be applied to a keyless entry device that performs locking and unlocking by wireless communication.

DESCRIPTION OF SYMBOLS 100 ... Keyless entry apparatus 200 ... 1st communication apparatus 210 ... LF transmission part 220 ... 1st LF sub transmission part 221 ... 1st LF transmission circuit 222 ... 1st LF transmission antenna 230 ... 2nd LF sub transmission Unit 231 ... second LF transmission circuit 232 ... second LF transmission antenna 240 ... RF reception unit 241 ... RF reception circuit 242 ... RF reception antenna 250 ... processing unit 260 ... storage unit 300 ... second communication device 310 ... LF Reception unit 311 ... LF reception circuit 312 ... LF reception antenna 320 ... RF transmission unit 321 ... RF transmission circuit 322 ... RF transmission antenna 330 ... processing unit 340 ... storage unit 400 ... vehicle 401 ... first position 402 ... second position 403 ... third position 404 ... fourth position 501 ... sine wave 502 ... sine wave 510 ... first LF signal 511 ... information signal 512 ... intensity measurement Signal 513... First authentication signal 520... Second LF signal 521... Second authentication signal 531... Composite authentication signal 532 ... Nodding 701 ... First unauthorized relay 702 ... Second unauthorized relay 711 ... LF Signal 712 ... Relay RF signal 713 ... Reproduction LF signal 714 ... Response RF signal 800 ... Second communication device 830 ... Processing unit 831 ... Transfer unit

Claims

A keyless device comprising a first communication device and a second communication device that perform wireless communication, and performs appropriate time processing when the wireless communication is appropriate and inappropriate time processing when the wireless communication is inappropriate An entry device,
The first communication device includes a transmission unit that wirelessly transmits a combined authentication signal having a plurality of authentication signals having sine waves of different frequencies as carrier waves,
At least one of the combined authentication signals is wirelessly transmitted from each of at least one location;
The second communication device includes a receiving unit that receives the combined authentication signal,
At least one of the first communication device and the second communication device further includes a processing unit, and the processing unit includes:
When the waveform of the composite authentication signal received by the receiving unit of the second communication device satisfies a first predetermined condition, the appropriate time process is performed,
When the waveform of the composite authentication signal received by the receiving unit of the second communication device does not satisfy the first predetermined condition, the improper processing is performed.
Keyless entry device.
The transmitting unit of the first communication device is
A first sub-transmitter that transmits at least one authentication signal of the plurality of authentication signals from a first position;
A second sub-transmission unit that transmits at least one other authentication signal of the plurality of authentication signals from a second position different from the first position;
The keyless entry device according to claim 1.
The processing unit is
In the synthetic authentication signal received by the receiving unit of the second communication device, the appropriateness is obtained when a waveform of at least one predetermined authentication signal among the plurality of authentication signals satisfies a second predetermined condition. Time processing,
In the composite authentication signal received by the receiving unit of the second communication device, when the waveform of the predetermined authentication signal does not satisfy the second predetermined condition, the improper processing is performed.
The keyless entry device according to claim 1 or 2.
The processing unit is
If the beat that satisfies the third predetermined condition exists in the composite authentication signal received by the receiving unit of the second communication device, the appropriate time processing is performed,
Performing the improper processing when there is no beat satisfying the third predetermined condition in the composite authentication signal received by the receiving unit of the second communication device;
The keyless entry device according to any one of claims 1 to 3.
The appropriate time process includes continuing communication between the first communication device and the second communication device;
The improper processing includes stopping communication between the first communication device and the second communication device;
The keyless entry device according to any one of claims 1 to 4.
The second communication device further includes a transmission unit,
The appropriate time processing includes transmitting information indicating that the wireless communication between the first communication device and the second communication device is appropriate from the transmission unit of the second communication device. ,
The improper processing transmits information indicating that the wireless communication between the first communication device and the second communication device is inappropriate from the transmission unit of the second communication device. including,
The keyless entry device according to any one of claims 1 to 5.
The second communication device is
A transmission unit;
A transfer unit that transmits information related to the waveform of the composite authentication signal received by the reception unit of the second communication device from the transmission unit of the second communication device;
The first communication device is
A receiving unit that receives the information from the transfer unit of the second communication device;
And at least a part of the processing unit,
The at least part of the processing unit included in the first communication device performs the appropriate time processing and the inappropriate time processing based on the information received by the first communication device.
The keyless entry device according to any one of claims 1 to 4.
Perform wireless communication with other communication devices, and perform appropriate time processing when the wireless communication is appropriate and inappropriate time processing when the wireless communication is inappropriate in cooperation with the other communication device. A communication device for a keyless entry device,
A transmitter that wirelessly transmits a composite authentication signal having a plurality of authentication signals with sine waves of different frequencies as carrier waves;
At least one of the combined authentication signals is wirelessly transmitted from each of at least one location;
In cooperation with the other communication device,
When the waveform of the composite authentication signal received by the receiving unit of the other communication device satisfies a predetermined condition, the appropriate time processing is performed,
When the waveform of the composite authentication signal received by the receiving unit of the other communication device does not satisfy the predetermined condition, the improper processing is performed.
Communication device for keyless entry device.
Perform wireless communication with other communication devices, and perform appropriate time processing when the wireless communication is appropriate and inappropriate time processing when the wireless communication is inappropriate in cooperation with the other communication device. A communication device for a keyless entry device,
A receiver for receiving a composite authentication signal having a plurality of authentication signals with sine waves of different frequencies as carrier waves from the other communication device;
In cooperation with the other communication device,
When the waveform of the composite authentication signal received by the receiving unit satisfies a predetermined condition, the appropriate time processing is performed,
When the waveform of the composite authentication signal received by the receiving unit does not satisfy the predetermined condition, the improper processing is performed.
Communication device for keyless entry device.
A control method for a keyless entry device that performs appropriate time processing when wireless communication between a first communication device and a second communication device is appropriate and incorrect time processing when the wireless communication is inappropriate. There,
The first communication device wirelessly transmits a composite authentication signal having a plurality of authentication signals having sine waves of different frequencies as carrier waves, and at least one of the composite authentication signals from each of at least one position. Wirelessly transmitting the authentication signal;
Receiving the composite authentication signal by the second communication device;
When the waveform of the composite authentication signal received by the second communication device satisfies a predetermined condition, processing is performed at an appropriate time,
Performing improper processing when the waveform of the composite authentication signal received by the second communication device does not satisfy the predetermined condition;
A method for controlling a keyless entry device.