JP6395319B2 - Mobile terminal device authentication system, in-vehicle device, and mobile terminal device - Google Patents

Description

  The present invention relates to a mobile terminal device authentication system, an in-vehicle device, and a mobile terminal device.

  Conventionally, two-way communication authentication technology that performs two-way communication between an in-vehicle device and a portable terminal device carried by a user to authenticate the terminal device, and locks and unlocks a door of a vehicle, starts an engine, etc. It has been known.

  In this connection, the vehicle-side device includes a vehicle-side control unit that performs predetermined control when the answer signal from the portable device is authenticated, and the portable device detects the strength of the request signal transmitted from the transmission antenna of the vehicle-side device. A portable device control unit, the vehicle side control unit controls the vehicle side transmission unit so that the intensity of the request signal transmitted from the transmission antenna changes midway, the portable device control unit of the request signal in the received signal A keyless entry device that detects the presence or absence of an intensity change corresponding to a change is known (see, for example, Patent Document 1).

  Further, in relation to the above technique, the step of transmitting the interrogation signal from the vehicle based on the transmitter, the step of receiving the interrogation signal by the portable communication device, and the second pulse of the second pulse with a difference of a predetermined identification threshold Determining whether the two amplitudes are greater than the first amplitude of the first pulse and determining that the interrogation signal is an authenticated interrogation signal, the interrogation signal comprising the second pulse For a vehicle with a passive keyless entry system, characterized in that it is determined to be an authenticated interrogation signal when it includes a first pulse transmitted at a first amplitude followed by a second pulse transmitted at A method for identifying unauthorized access is known (see, for example, Patent Document 2).

JP 2010-185186 A US Patent Application Publication No. 2008/0143500

  However, in the conventional technique, there is a possibility that an unauthorized signal is authenticated by an authentication technique such as a relay attack.

  The present invention has been made in view of such circumstances, and has an object to provide a mobile terminal device authentication system, an in-vehicle device, and a mobile terminal device that can improve the security of authentication. To do.

The portable terminal device authentication system of the present invention employs the following configuration.
(1) The in-vehicle side transmitting unit that transmits the signal, the in-vehicle side receiving unit that receives the signal, and the in-vehicle side transmitting unit transmit the request signal, and the signal received by the in-vehicle side receiving unit is a regular signal. A vehicle-mounted device having a vehicle-mounted control unit that determines whether or not there is a mobile-side receiving unit that receives a signal, a mobile-side transmitting unit that transmits a signal, and the mobile-side receiving unit receives the request signal. A portable terminal device that controls the portable transmission unit so as to transmit an answer signal to the request signal in response to the request signal. A signal including a plurality of authentication signals different from each other is transmitted to the in-vehicle side transmission unit as the request signal, the portable side reception unit receives the request signal transmitted by the in-vehicle side transmission unit, The portable side control unit determines the plurality of authentication signals based on signal strengths of the plurality of authentication signals included in the request signal received by the portable side reception unit, and the portable side reception unit The reception time of the authentication signal included in the received request signal is measured for each of the determined authentication signals, and the signal including the information indicating the measured reception time is included in the in-vehicle device, The mobile side transmission unit transmits the answer signal as an answer signal, and the in-vehicle side control unit determines whether or not the signal received by the in-vehicle side reception unit includes information indicating the reception time of the authentication signal. When the signal received by the in-vehicle side reception unit includes information indicating the reception time of the authentication signal, the in-vehicle side is based on the information indicating the reception time of the authentication signal. Signal received by the signal unit, and to determine whether the answer signal transmitted by the portable side transmitter unit.

  According to such a configuration, the in-vehicle side control unit causes the in-vehicle side transmission unit to transmit a signal including a plurality of authentication signals having different signal strengths as a request signal. The portable side receiving unit receives the request signal transmitted by the in-vehicle side transmitting unit, and the portable side control unit is based on the signal strengths of the plurality of authentication signals included in the request signal received by the portable side receiving unit. , Discriminating a plurality of authentication signals, measuring the reception time of the authentication signal included in the request signal received by the mobile-side receiver for each of the determined authentication signals, and receiving the timed reception for the in-vehicle device A signal including information indicating time is transmitted as an answer signal to the portable-side transmitting unit. The in-vehicle side control unit determines whether or not the signal received by the in-vehicle side reception unit includes information indicating the reception time of the authentication signal, and the signal received by the in-vehicle side reception unit includes the authentication signal. If the information indicating the reception time is included, whether the signal received by the in-vehicle side reception unit is an answer signal transmitted by the mobile side transmission unit based on the information indicating the reception time of the authentication signal Determine whether or not. As a result, the mobile terminal device authentication system can improve the security of authentication.

(2) The in-vehicle side control unit compares the transmission time of the authentication signal with the reception time of the authentication signal, and based on the comparison result, the signal received by the in-vehicle side reception unit is You may determine whether it is an answer signal transmitted by the portable side transmission part.

  According to this configuration, the mobile terminal device authentication system can improve the security of authentication as in the above configuration.

(3) The authentication signal includes a first signal and a second signal having a signal strength smaller than that of the first signal, and the vehicle-mounted control unit transmits the first signal. Compare the time with the reception time of the first signal, compare the transmission time of the second signal with the reception time of the second signal, and based on the comparison result, You may make it determine whether the received signal is an answer signal transmitted by the said portable side transmission part.

  According to such a configuration, the mobile terminal device authentication system can compare the transmission time and the reception time for each authentication information, and therefore can improve the determination accuracy at the time of authentication.

(4) The in-vehicle side control unit may cause the in-vehicle side transmission unit to transmit the request signal with a transmission time determined randomly.

  According to the structure which concerns, the confidentiality of information improves and the portable terminal device authentication system can raise the determination precision at the time of authentication more.

The on-vehicle apparatus of the present invention employs the following configuration.
(5) The in-vehicle side transmitting unit that transmits the request signal, the in-vehicle side receiving unit that receives the signal, and a signal including a plurality of authentication signals having different signal strengths are transmitted to the in-vehicle side transmitting unit as the request signal. Determining whether the signal received by the in-vehicle side receiving unit includes information indicating the reception time of the authentication signal, and receiving the authentication signal in the signal received by the in-vehicle side receiving unit Whether or not the signal received by the in-vehicle side receiving unit is an answer signal to the request signal based on the information indicating the reception time of the authentication signal when the information indicating the time is included. And a vehicle-mounted side control unit for determination.

  According to this configuration, the in-vehicle side control unit causes the in-vehicle side transmission unit to transmit a signal including a plurality of authentication signals having different signal strengths as a request signal, and the signal received by the in-vehicle side reception unit is used as the authentication signal. It is determined whether or not information indicating the reception time of the authentication signal is included, and when the signal received by the in-vehicle side reception unit includes information indicating the reception time of the authentication signal, the reception time of the authentication signal It is possible to determine whether or not the signal received by the in-vehicle side receiving unit is an answer signal corresponding to the request signal based on the information indicating.

The portable terminal device of the present invention employs the following configuration.
(6) A mobile-side receiver that receives a request signal, a mobile-side transmitter that transmits an answer signal to the request signal, and a plurality of authentication signals included in the request signal received by the mobile-side receiver Based on the strength, the plurality of authentication signals are determined, and the reception time of the authentication signal included in the request signal received by the mobile-side receiving unit is counted for each of the determined authentication signals, A portable side control unit that causes the portable side receiving unit to transmit a signal including information indicating the measured reception time to the portable side transmitting unit as the answer signal with respect to a signal reception source by the portable side receiving unit. .

  According to this configuration, the mobile side control unit determines a plurality of authentication signals based on the signal strengths of the plurality of authentication signals included in the request signal received by the mobile side reception unit, and the mobile side reception unit The reception time of the authentication signal included in the request signal received by the device is counted for each identified authentication signal, and information indicating the measured reception time is included with respect to the signal reception source by the mobile-side receiving unit. The signal can be transmitted as an answer signal to the mobile-side transmitter.

  According to the present invention, it is possible to provide a mobile terminal device authentication system, an in-vehicle device, and a mobile terminal device that can improve the security of authentication.

It is a block diagram which shows the portable terminal device authentication system. 4 is a diagram illustrating an example of a configuration of an in-vehicle side transmission unit 40. FIG. 3 is a diagram illustrating an example of a configuration of a mobile-side receiving unit 210. FIG. It is explanatory drawing which shows the frame structure of the request signal transmitted by LF communication of this embodiment. 4 is a flowchart illustrating an example of a processing flow of an in-vehicle side control unit 30. 6 is a flowchart illustrating an example of a process flow of a portable control unit 230. It is a figure for demonstrating the determination method whether the 1st information for authentication AUD1 was complete | finished. It is explanatory drawing which shows the frame structure of the answer signal transmitted by RF communication of this embodiment. 4 is a timing chart illustrating an example of operation timing of each unit of the in-vehicle side control unit 30.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on one embodiment of the present invention shown in the accompanying drawings.

  FIG. 1 is a configuration diagram showing a mobile terminal device authentication system 1. The mobile terminal device authentication system 1 shown in the figure is applied to a vehicle such as an automobile or a motorbike, and restricts the use of the vehicle when locked. The mobile terminal device authentication system 1 can drive a device corresponding to an object to be controlled such as locking, unlocking, or starting an engine by authenticating the mobile terminal device 200 without using a mechanical key.

  For example, a power unit P including an engine E and a transmission (not shown) is swingably supported on a body frame of a scooter V that is a small vehicle, and a rear wheel WF that is driven by the power unit P is a rear portion of the power unit P. Is pivotally supported. When the power unit P is in the locked state, driving is restricted (driving restricted state). A handle H is provided at the front of the body frame of the scooter V, and the handle H is supported via a connecting shaft so that the direction of the front wheel WR can be adjusted. When the handle H is in the locked state, the rotation of the connecting shaft is restricted by the handle lock portion 16. The handle lock unit 16 includes an actuator unit 18 including a mechanism that limits the rotation of the connecting shaft.

  The power unit P is provided with a kick actuating portion 7 that can drive the generator G included in the power unit P by an operation of depressing the kick pedal 6. For example, when the battery runs out, the scooter V can use the electric power obtained by generating power by the kick operation of the kick operation unit 7.

  A battery B is mounted on the scooter V, and the starting method of the power unit P is switched according to the state of charge (terminal voltage) of the battery B.

  Electric power generated by the generator G is supplied to the battery B via the converter 8. When the engine E is being driven, the generator G is driven by the engine E. For example, the battery B is charged by the electric power output from the generator G by depressing the kick pedal 6 of the kick operating unit 7. In this case, the converter 8 functions as a rectifier and a regulator.

  Furthermore, the electric power stored in the battery B may be supplied to the generator G, and the generator G may be used as a starter for the engine E. In this case, the converter 8 supplies power so that the generator G functions as a motor.

  In addition, ignition power (not shown) provided in the engine E is supplied from the ignition circuit 13 according to the state of the main relay (MRY) 12.

  By the way, for example, when it is verified that the mobile terminal device 200 is a legitimate device corresponding to the scooter V, the in-vehicle device 100 cancels various restriction states. Various restriction states include locking of the handle H and driving restriction of the power unit P.

(Configuration of in-vehicle device 100)
The in-vehicle device 100 includes a power source unit 20, an in-vehicle side control unit 30, an in-vehicle side transmission unit 40, an in-vehicle side reception unit 50, a drive circuit unit 61, an input circuit unit 62, and a main switch state acquisition unit 63. The main relay drive unit 64 is provided. Further, the in-vehicle device 100 may be configured to include a starter driving unit 65.

  The power supply unit 20 uses the battery B or the generator G as a power source, stabilizes the terminal voltage of the battery B with reference to the voltage + Vreg, and supplies the stabilized voltage to each unit such as the in-vehicle control unit 30. Each unit such as the in-vehicle control unit 30 uses a stabilized DC voltage as a power source. The power supply unit 20 monitors the voltage drop below the predetermined threshold voltage VTH of the terminal voltage of the battery B, and outputs the detection result.

  The in-vehicle side transmission unit 40 transmits a request signal for calling the mobile terminal device 200. A signal transmitted from the in-vehicle side transmission unit 40 may be referred to as an LF signal. In the request signal (LF signal), identification information for identifying the mobile terminal device 200 (hereinafter referred to as “mobile terminal device identification information”) and a plurality of pieces of authentication processing information (hereinafter referred to as “authentication information”). ) And In the present embodiment, in order to simplify the description, as a plurality of pieces of authentication information included in the request signal, two types of information, ie, first authentication information and second authentication information will be representatively described. The authentication information is not limited to only this information. For example, third and fourth authentication information may be included. The authentication information is an example of an “authentication signal”. The first authentication information and the second authentication information are examples of “first signal” and “second signal”, respectively.

  The in-vehicle side receiving unit 50 receives a signal transmitted by an external device. For example, the in-vehicle side receiving unit 50 receives a signal transmitted by the mobile terminal device 200. Hereinafter, a signal transmitted from the mobile terminal device 200 and received by the in-vehicle side receiving unit 50 may be referred to as an RF signal. The carrier frequency of the RF signal is relatively higher than the carrier frequency of the LF signal.

  The drive circuit unit 61 drives the actuator unit 18 while the main switch 11 is in a conductive state. For example, the main switch 11 is turned on or off by a physical key. The actuator unit 18 is included in the handle lock unit 16 that locks the handle H in order to disable traveling of the vehicle, and switches between locking and unlocking of the handle lock unit 16.

  When the main switch 11 is in the conductive state, the drive circuit unit 61 drives the actuator unit 18 to unlock the handle H and keep the locked state. When the main switch 11 is in a non-conducting state, the drive circuit unit 61 drives the actuator unit 18 to unlock the handle H and keep the unlocked state.

  The input circuit unit 62 receives a signal from the activation switch 17. The start switch 17 is provided on the handle H, for example, and is operated by the occupant so as to be in an on state or an off state.

  The main switch state acquisition unit 63 acquires the conduction state of the main switch 11 that can be turned on according to the operation of the occupant.

  The main relay drive unit 64 switches between an on state and an off state of the main relay 14 under the control of the in-vehicle side control unit 30.

  The starter drive unit 65 supplies a drive signal for starting the power unit P under the control of the in-vehicle side control unit 30. For example, the starter drive unit 65 supplies a drive signal when using the generator G as a starter of the engine E to the conversion unit 8.

  The in-vehicle side control unit 30 includes a start control unit 31, a communication control unit 32, a determination unit 33, a drive control unit 34, and a storage unit 35. Some or all of the start control unit 31, the communication control unit 32, the determination unit 33, and the drive control unit 34 are software functions that function when a processor such as a CPU (Central Processing Unit) executes a program. Part. Some or all of these may be hardware function units such as LSI (Large Scale Integration) and ASIC (Application Specific Integrated Circuit). The storage unit 35 is realized by a ROM (Read Only Memory), a RAM (Random Access Memory), an HDD (Hard Disk Drive), a flash memory, or the like. The program executed by the processor may be stored in advance in the storage unit 35 or may be downloaded from an external device. Further, the portable storage medium storing the program may be installed in the storage unit 35 by being mounted on a drive device (not shown).

  For example, the storage unit 35 holds a program for causing each unit of the in-vehicle side control unit 30 to function, identification information of the mobile terminal device 200 corresponding to the in-vehicle device 100, and the like.

  The start controller 31 detects a request signal transmission request. The request signal transmission request is caused by, for example, an operation of the activation switch 17. For example, the start control unit 31 transmits a request signal when the main switch 11 is in an off state, that is, when the handle H is in a locked state (the vehicle cannot travel) and the start switch 17 is in an on state. Detect requests.

  When the start control unit 31 detects a request signal transmission request, the communication control unit 32 controls the in-vehicle side transmission unit 40 to transmit the request signal. More specifically, the communication control unit 32 indicates that the start switch 17 is turned on when the main switch 11 is in the off state, that is, when the handle H is in the locked state (the vehicle cannot travel). Sometimes, the in-vehicle side transmission unit 40 is caused to transmit a request signal.

  In a situation where the communication control unit 32 causes the in-vehicle side transmission unit 40 to transmit a request signal, the battery B stores power necessary for transmitting the request signal in response to a request signal transmission request. Shall.

  On the other hand, when the power required for transmitting the request signal is not stored in the battery B, the main switch 11 is turned on, and the kick operating unit 7 that drives the generator G that supplies power to the in-vehicle device 100 is operated. The system waits until necessary power is stored in the battery B.

  The determination unit 33 decodes the signal received by the in-vehicle side reception unit 50, and determines whether the signal received by the in-vehicle side reception unit 50 is a signal for the request signal based on the decoded result. Hereinafter, a signal corresponding to the request signal is referred to as an “answer signal”.

  For example, when the signal received by the in-vehicle side receiving unit 50 is an answer signal transmitted by the mobile terminal device 200 that is the transmission destination of the request signal, the determining unit 33 is the receiving source of the in-vehicle side receiving unit 50 It is determined that the device (in this case, the mobile terminal device 200) is a predetermined regular device, and it is determined that the authentication has succeeded.

  On the other hand, when the signal received by the in-vehicle side receiving unit 50 is not the answer signal transmitted by the mobile terminal device 200 that is the transmission destination of the request signal, the determining unit 33 receives the device from the in-vehicle side receiving unit 50. Is not a predetermined regular device, and it is determined that the authentication has failed. For example, when a signal is transmitted from a device different from the mobile terminal device 200, the determination unit 33 determines that this device is not a regular device.

  The determination unit 33 determines the operating state of the activation switch 17 based on the signal input from the input circuit unit 62.

  Further, the determination unit 33 determines whether or not a signal is received by the in-vehicle side reception unit 50.

  The drive control unit 34 controls the lock state of the handle H and the start limit of the engine E according to the determination result of the determination unit 33. For example, when it is determined by the determination unit 33 that the authentication is successful, the drive control unit 34, that is, the signal received by the in-vehicle side reception unit 50 is transmitted by the mobile terminal device 200 that is the transmission destination of the request signal. If the response signal is a response signal, the locked state of the steering wheel is released and the engine E start restriction is released. For example, the drive control unit 34 drives the actuator unit 18 of the handle lock unit 16 via the drive circuit unit 61 to release the lock state of the handle. The drive control unit 34 starts the engine E by driving the generator G via the starter driving unit 65.

(Configuration of mobile terminal device 200)
The mobile terminal device 200 is authenticated by the in-vehicle device 100. Identification information of the mobile terminal device 200 is stored in the storage unit 35 of the in-vehicle device 100. The mobile terminal device 200 includes a mobile side receiving unit 210, a mobile side transmitting unit 220, and a mobile side control unit 230.

  The mobile-side receiving unit 210 receives a request signal transmitted by the in-vehicle device 100. The portable side transmission unit 220 transmits the answer signal generated by the portable side control unit 230 to the in-vehicle device 100 that is the reception source of the request signal.

  The portable side control unit 230 includes, for example, a signal strength measurement unit 231, a reception time counting unit 232, and a signal generation unit 233. The signal strength measuring unit 231 measures the signal strength of the request signal received by the mobile-side receiving unit 210.

  The reception time counting unit 232 measures the reception time of the request signal received by the portable side reception unit 210 based on the measurement result by the signal strength measurement unit 231. The signal generation unit 233 generates an answer signal corresponding to the request signal received by the mobile-side receiver 210 and causes the mobile-side transmitter 220 to transmit the answer signal.

  Note that some or all of the mobile-side receiving unit 210, the mobile-side transmitting unit 220, and the mobile-side control unit 230 may be software function units that function when a processor such as a CPU executes a program. Further, some or all of these may be hardware function units such as an LSI or an ASIC. Further, the portable control unit 230 may include a storage unit (not shown), and the storage unit may be realized by a ROM, a RAM, an HDD, a flash memory, or the like. The program executed by the processor may be stored in the storage unit in advance or may be downloaded from an external device. Further, the portable storage medium storing the program may be installed in the storage unit by being mounted on a drive device (not shown).

  FIG. 2 is a diagram illustrating an example of the configuration of the in-vehicle side transmission unit 40. The in-vehicle side transmission unit 40 includes, for example, a modulation unit 41, a local oscillation unit 42, a mixer 43, a transmission circuit unit 44, and a transmission antenna 45.

  The modulation unit 41 modulates the signal input from the vehicle-mounted side control unit 30 based on a modulation scheme such as ASK (amplitude-shift keying) or PSK (phase-shift keying).

  The mixer 43 mixes the signal modulated by the modulating unit 41 and the signal output by the local oscillating unit 42, and transmits a signal (for example, a beat signal) whose frequency is the sum or difference of both signals to the transmission circuit unit 44. Output to.

  The transmission circuit unit 44 performs gain amplification, noise removal, filtering processing, and the like of the signal input from the mixer 43 and outputs the result to the transmission antenna 45.

  The transmitting antenna 45 radiates radio waves based on the signal output by the transmitting circuit unit 44 into the atmosphere.

  FIG. 3 is a diagram illustrating an example of the configuration of the mobile-side receiving unit 210. The mobile-side receiving unit 210 includes, for example, a receiving antenna 211, a receiving circuit unit 212, a local oscillating unit 213, a mixer 214, and a demodulating unit 215.

  The reception circuit unit 212 performs amplification of the gain of the signal received by the reception antenna 211, noise removal, filtering processing, and the like, and outputs the result to the mixer 214.

  The mixer 214 converts the frequency of the signal output from the reception circuit unit 212 based on the signal output from the local oscillation unit 213. For example, the mixer 214 outputs a beat signal generated from the difference between the frequency of the signal output from the reception circuit unit 212 and the frequency of the signal output from the local oscillation unit 213 to the demodulation unit 215.

  The demodulation unit 215 demodulates the signal output from the mixer 214 with respect to the modulation method of the modulation unit 41 described above, and outputs the demodulated signal to the portable control unit 230.

(Request signal frame structure)
With reference to FIG. 4, the frame structure of the request signal transmitted by LF communication of this embodiment is demonstrated. FIG. 4 is an explanatory diagram showing a frame structure of a request signal transmitted by LF communication according to the present embodiment. Hereinafter, the frame structure of the request signal will be described as a pattern LFP.

  The time required for frame transmission of the pattern LFP is indicated as TLFP. As shown in FIG. 4, for example, the pattern LFP includes mobile terminal device information and authentication information. The mobile terminal device information includes at least training data TD, a frame header FH1, and identification information IDk, and the authentication information includes first authentication information AUD1 and second authentication information AUD2. Further, the mobile terminal device information may include data such as error correction information ECC1.

  The training data TD is arranged so as to be transmitted first when the pattern LFP is transmitted. The training data TD is assigned a signal pattern required for adjustment of the mobile-side receiving unit 210 when the mobile terminal device 200 receives the pattern LFP.

  The frame header FH1 is arranged to be transmitted next to the training data TD, for example. The frame header FH1 includes a signal pattern used as an index when various information is extracted after the mobile-side receiving unit 210 finishes training using the training data TD, and information for identifying the pattern type.

  The identification information IDk is identification information that identifies the mobile terminal device that is the transmission destination (destination) of the pattern LFP.

  The error correction information ECC1 is information for performing error detection and error correction of each data such as the received identification information IDk in the pattern LFP. The error correction information ECC1 can appropriately determine an error detection and error correction target range, an error detection and error correction method, and the like for each pattern type.

  The first authentication information AUD1 and the second authentication information AUD2 included in the pattern LFP indicate, for example, information (encryption key, ciphertext, etc.) required for encryption processing. A general algorithm can be applied to the cryptographic processing method. In the encryption process, the information encrypted in the in-vehicle device 100 is decrypted by the mobile terminal device 200, and the determination of the decrypted information is performed by either the mobile terminal device 200 or the in-vehicle device 100. Good.

(Processing of the in-vehicle side control unit 30)
Hereinafter, with reference to FIG. 5, the process of the vehicle-mounted side control part 30 of this embodiment is demonstrated. FIG. 5 is a flowchart illustrating an example of a process flow of the in-vehicle side control unit 30. The processing in this flowchart is performed when the main switch 11 is in an off state, that is, when the handle H is in a locked state (a state where the vehicle can travel).

  First, the determination unit 33 determines the operating state of the activation switch 17 based on the signal input from the input circuit unit 62 (step S100). When the start switch 17 is in the OFF state, the vehicle-mounted side control unit 30 ends the process of this flowchart.

  On the other hand, the communication control part 32 sets the transmission frequency of a request signal, when the starting switch 17 is an ON state (step S102).

  For example, the communication control unit 32 sets the frequency f1 when sending the first authentication information AUD1 and the frequency f2 when sending the second authentication information AUD2 to the gain of the transmission antenna 45 described above ( It is set on the basis of frequency characteristics (hereinafter referred to as “resonance characteristics”) with respect to (signal intensity). For example, the frequency f1 is set to a value closer to the resonance frequency f0 of the transmitting antenna 45 than the frequency f2.

  The communication control unit 32 can easily change the signal strength of the request signal, and the signal strength of the radio wave when the first authentication information AUD1 is sent and the second authentication information AUD2 are sent. The request signal can be transmitted in such a manner that the signal strength of the radio wave at that time is different.

  Next, the communication control unit 32 sets the transmission time of the request signal (step S104). Note that the process of step S104 may be performed before step S102.

  For example, the communication control unit 32 determines the time TAUD1 for sending the first authentication information AUD1 and the time TAUD2 for sending the second authentication information AUD2 in a random (random) manner. At this time, the time TAUD1 and the time TAUD2 may be the same or different. Thereby, the communication control part 32 can improve the confidentiality of the information regarding the time TAUD1 and the time TAUD2.

  The communication control unit 32 stores the determined time TAUD1 and time TAUD2 in the storage unit 35, and when the time TAUD1 and the time TAUD2 are set again, for example, the time set this time on the previously stored information. The information of TAUD1 and time TAUD2 is overwritten. That is, the communication control unit 32 updates the information on the time TAUD1 and the time TAUD2 in the storage unit 35 every time the time TAUD1 and the time TAUD2 are set.

  The communication control unit 32 transmits a request signal to the mobile terminal device 200 based on the set transmission frequency (frequency f1, f2) and transmission time (time TAUD1, TAUD2) (step S106).

  For example, the communication control unit 32 transmits a request signal having a frame structure as illustrated in FIG. 4 to the mobile terminal device 200. The communication control unit 32 sets the frequency of the signal output from the local oscillation unit 42 to a predetermined frequency, and causes the in-vehicle side transmission unit 40 to transmit the mobile terminal device information.

  In addition, the communication control unit 32 sets the frequency of the signal output from the local oscillation unit 42 to the frequency f1, and causes the in-vehicle side transmission unit 40 to transmit the first authentication information AUD1 over time TAUD1. The frequency f1 may be the same as or different from the frequency (predetermined frequency) at the time of transmitting the mobile terminal device information.

  Further, the communication control unit 32 sets the frequency of the signal output from the local oscillation unit 42 to the frequency f2, and causes the in-vehicle side transmission unit 40 to transmit the second authentication information AUD2 over time TAUD2.

  Next, the determination unit 33 determines whether a signal is received by the in-vehicle side reception unit 50 (step S108). When the signal is not received by the in-vehicle side receiving unit 50, the in-vehicle side control unit 30 stands by until the signal is received.

  On the other hand, when the signal is received by the in-vehicle side receiving unit 50, the determination unit 33 receives the time required for receiving the authentication information in the signal received by the in-vehicle side receiving unit 50 (hereinafter, “reception time”). It is determined whether or not the information indicating (referred to as) is included (step S110).

  When the signal received by the in-vehicle side reception unit 50 includes information indicating the reception time, the determination unit 33 transmits the transmission time stored in the storage unit 35, that is, the transmission set by the communication control unit 32. It is determined whether or not the time matches the reception time (step S112).

  When the transmission time and the reception time match, the determination unit 33 determines that the signal received by the in-vehicle side reception unit 50 is an answer signal transmitted by the mobile terminal device 200 that is the transmission destination of the request signal. . Along with the coincidence of the transmission / reception times of the authentication information, confirmation of coincidence of portable device ID information included in the answer signal, confirmation of whether the RSSI strength (reception strength of the first authentication information AUD1) is equal to or greater than a predetermined threshold, and encryption When the confirmation of the coincidence of the encryption data by decrypting the data is confirmed, the determination unit 33 determines that the mobile terminal device 200 that is the communication counterpart of the in-vehicle side reception unit 50 is a legitimate device and succeeds in the authentication. It is determined that it has been performed (step S114).

  On the other hand, when the signal received by the in-vehicle side reception unit 50 does not include information indicating the reception time, or when the transmission time and the reception time do not match, the determination unit 33 determines that the in-vehicle side reception unit 50 It is determined that the received signal is not an answer signal transmitted by the mobile terminal device 200 that is the transmission destination of the request signal. The determination unit 33 determines that the device that is the communication partner of the in-vehicle side reception unit 50 is not a regular device, and determines that the authentication has failed. That is, in the mobile terminal device authentication system of the present embodiment, even if the determination unit 33 confirms that the mobile device ID information matches or the like (with a relay attack using a relay device, If there is no match between the transmission time and the reception time of the authentication information, it is determined that the device that is the communication partner of the in-vehicle side receiving unit 50 is not a regular device (step S116).

  After the process of step S114, the vehicle-mounted side control unit 30 (drive control unit 34) controls the drive unit (solenoid) of each unit to be driven to unlock the locked state of each unit (step S118). Thereby, the processing of this flowchart is completed.

(Processing of portable side control unit 230)
Hereinafter, with reference to FIG. 6, the process of the portable-side control unit 230 of the present embodiment will be described. FIG. 6 is a flowchart illustrating an example of a process flow of the portable control unit 230.

  First, the mobile side control unit 230 determines whether or not the mobile side receiving unit 210 has started receiving a request signal (step S200). When reception of a request signal is not started by the mobile-side receiving unit 210, the process of this flowchart ends.

  When reception of the request signal is started by the mobile-side receiving unit 210, the reception time measuring unit 232 determines whether or not reception of the first authentication information AUD1 is started in the frame structure (pattern LFP) of the request signal. Determination is made (step S202).

  For example, the reception time counting unit 232 starts counting the time when the reception of the request signal is started, that is, when the information for the mobile terminal device is started in the frame structure (pattern LFP) of the request signal. When the data arranged at the end of the device information can be confirmed, it is determined that the reception of the first authentication information AUD1 is started.

  The reception time counting unit 232 counts the number of standby when reception of the first authentication information AUD1 is not started. On the other hand, when reception of the first authentication information AUD1 is started, the reception time counting unit 232 counts the reception time TAUD1 # of the first authentication information AUD1 (step S204).

  For example, the reception time counting unit 232 counts the reception time TAUD1 # of the first authentication information AUD1 in response to the completion of reception of data arranged at the end of the mobile terminal device information.

  When the data indicating the transmission time of the mobile terminal device information is stored in the mobile terminal device information, the reception time counting unit 232 transmits the request signal reception start time and the mobile terminal device information. Based on the data indicating the time, the reception start time of the first authentication information AUD1 (or the end time of the mobile terminal device information) is calculated, and the reception time of the first authentication information AUD1 is calculated from the calculation time. You may start counting TAUD1 #.

  Further, the reception time counting unit 232 may start counting the reception time TAUD1 # of the first authentication information AUD1 from the start time of the mobile terminal device information. In this case, the reception time counting unit 232 subtracts the time required for receiving the mobile terminal device information from the count result of the reception time TAUD1 # to derive the actual reception time TAUD1 #.

  Next, the reception time measuring unit 232 determines whether or not the first authentication information AUD1 has been completed in the frame structure (pattern LFP) of the request signal based on the measurement result by the signal strength measuring unit 231 (step) S206).

  FIG. 7 is a diagram for explaining a method for determining whether or not the first authentication information AUD1 has ended. SIG shown in FIG. 7 represents a request signal received by the mobile-side receiving unit 210. The vertical axis represents signal intensity (for example, the unit is “dB”), and the horizontal axis represents time (for example, the unit is “ms”).

  For example, the signal strength measuring unit 231 measures the signal strength of the request signal at the same time when the mobile-side receiving unit 210 starts receiving the request signal. Specifically, envelope detection is performed to acquire an envelope from the signal waveform of the request signal, and the signal intensity is measured. For example, an envelope detected on the upper limit side of the waveform relating to the signal intensity is represented as EL1, and an envelope detected on the lower limit side of the amplitude is represented as EL2.

  The reception time measuring unit 232 determines, for example, whether or not the amplitude W1 between the envelopes EL1 and EL2 detected by the signal strength measuring unit 231 is equal to or greater than the threshold Th, and the first authentication information AUD1. It is determined whether or not the process has ended. In the example of FIG. 7, the signal strength measuring unit 231 ends the first authentication information AUD1 when the amplitude W1 of the signal strength is equal to or less than the threshold Th in the first authentication information AUD1 (time Tc). It is determined that the second authentication information AUD2 has started. Therefore, the reception time counting unit 232 counts the period from the end time of the data arranged at the end of the mobile terminal device information to the time Tc as the reception time TAUD1 # of the first authentication information AUD1, and the time Tc The subsequent period is counted as the reception time TAUD2 # of the second authentication information AUD2. Note that a plurality of threshold values Th may be provided, and envelopes may be provided as different threshold values for EL1 and EL2.

  When the first authentication information AUD1 does not end, that is, when the amplitude W1 of the signal strength does not fall below the threshold Th in the first authentication information AUD1, the reception time counting unit 232 continues to count the reception time TUD1 # To do.

  On the other hand, when the first authentication information AUD1 is completed, that is, when the signal strength amplitude W1 is less than or equal to the threshold Th in the first authentication information AUD1, the reception time timer 232 receives the reception time TAUD1 #. The counting is terminated and stored in a storage unit (not shown) (step S208), and counting of the reception time TAUD2 # of the second authentication information AUD2 is started (step S210).

  Next, the reception time counting unit 232 determines whether or not the second authentication information AUD2 is completed in the frame structure (pattern LFP) of the request signal based on the measurement result by the signal strength measurement unit 231 (step S2). S212).

  For example, the reception time measuring unit 232 has substantially zero amplitude W2 between the envelopes EL1 and EL2 detected by the signal strength measuring unit 231 when the second authentication information AUD2 is received (after time Tc). In some cases, it is determined that the second authentication information AUD2 has ended. When the amplitude W2 is not substantially zero, it is determined that the second authentication information AUD2 has not ended.

  If the second authentication information AUD2 has not ended, the reception time counting unit 232 continues to count the reception time TAUD2 #. On the other hand, when the second authentication information AUD2 ends, the reception time timer 232 ends the count of the reception time TAUD2 # and stores it in a storage unit (not shown) (step S214).

  Next, the signal generation unit 233 generates an answer signal having a predetermined frame structure, and causes the portable-side transmission unit 220 to transmit it (step S216). Thereby, the process of this flowchart is complete | finished.

(Answer signal frame structure)
FIG. 8 is an explanatory diagram showing a frame structure of an answer signal transmitted by RF communication according to the present embodiment. Hereinafter, the frame structure of the answer signal will be described as a pattern RFA.

  As shown in FIG. 8, for example, the pattern RFA indicates the in-vehicle device information, the information indicating the reception time TAUD1 # of the first authentication information AUD1, and the reception time TAUD2 # of the second authentication information AUD2. Information. The in-vehicle device information includes at least training data TD and a frame header FH2. Further, the in-vehicle device information may include data such as error correction information ECC2. It is assumed that time TRFA is required for sending an answer signal having the frame structure of pattern RFA.

  The training data TD is arranged to be transmitted first when the pattern RFA is transmitted. A signal pattern required for adjustment of the in-vehicle side receiving unit 50 when the in-vehicle device 100 receives the pattern RFA is assigned to the training data TD.

  The frame header FH2 is arranged so as to be transmitted next to the training data TD, for example. The frame header FH2 includes a signal pattern used as an index when extracting various types of information after the in-vehicle-side receiving unit 50 finishes training using the training data TD, and information for identifying the pattern type.

  The error correction information ECC2 is information for performing error detection and error correction of each data such as information indicating the received reception time TAUD1 # in the pattern RFA. The error correction information ECC2 can appropriately determine an error detection and error correction target range, an error detection and error correction method, and the like for each type of pattern.

  Accordingly, the determination unit 33 of the in-vehicle device 100 receives the reception time TAUD1 # of the first authentication information AUD1 and the second authentication information AUD2 from the answer signal having the frame structure (FLP2) as illustrated in FIG. The reception time TAUD2 # is acquired and compared with the transmission time TAUD1 and the reception time TAUD1 #, and by comparing the transmission time TAUD2 and the reception time TAUD2 #, each reception time matches the corresponding transmission time or predetermined Can be determined that the signal received by the in-vehicle side receiver 50 is an answer signal for the request signal.

  Hereinafter, with reference to FIG. 9, the operation timing of each part of the vehicle-mounted side control part 30 is demonstrated. FIG. 9 is a timing chart illustrating an example of operation timing of each unit of the in-vehicle side control unit 30. In the example of FIG. 9, it is assumed that the voltage of the battery B is sufficiently high and does not require a kick operation.

  In FIG. 9, (a) start switch, (b) control unit start, (c) initialization process, (d) main switch, (e) main switch determination value, (f) LF transmission, (g) mobile terminal Each state of apparatus side processing, (h) RF reception, (i) RF data determination, (j) solenoid control, and (k) unlocking is shown.

  At time t20, when the operation of the start switch 17 is detected (0 V), the control unit start is instructed to the in-vehicle side control unit 30 (“control unit start: ON”). In response to this instruction, the vehicle-mounted control unit 30 performs the initialization process and ends by time t25. The initialization process includes a process for setting an input / output port corresponding to a peripheral part of the in-vehicle side control unit 30 and a process for adjusting an initial state of the in-vehicle side receiving unit 50.

  The in-vehicle side control unit 30 detects that the main switch 11 is in an OFF state based on the result of acquiring the conduction state of the main switch 11 by the main switch state acquisition unit 63, and the determination result of the main switch (Main switch determination value) is kept off (OFF).

  The communication control unit 32 causes the in-vehicle side transmission unit 40 to start transmitting a request signal (LFP) by LF communication at time t111, and ends transmission of the request signal (LFP) at time t112.

  The mobile-side control unit 230 (signal generation unit 233) generates an answer signal (RFA) based on the request signal (LFP) received by the mobile-side reception unit 210 during the period from time t111 to time t112 (TLFP). To do. The portable side control unit 230 (signal generation unit 233) causes the portable side transmission unit 220 to start transmitting an answer signal (RFA) by RF communication at time t112, and transmits an answer signal (RFA) at time t113. Terminate.

  The determination unit 33 performs authentication determination (RF data determination) of the mobile terminal device 200 based on the answer signal (RFA) received by the in-vehicle side reception unit 50 in the period from time t112 to time t113 (TRFA). When the authentication of the mobile terminal device 200 is successful, the determination value of the authentication determination (RF data determination) is set to 1 (on).

  When the authentication of the mobile terminal device 200 is successful (time t114), the in-vehicle side control unit 30 (drive control unit 34) controls the drive unit (solenoid) of each unit to be driven to unlock the locked state of each unit. To do. Thereby, the locked state of each part is unlocked after time t115.

  According to the mobile terminal device authentication system 1 in the embodiment described above, the in-vehicle side control unit 30 sends a request signal including a plurality of pieces of authentication information having different signal strengths to the in-vehicle side transmission unit 40 to the mobile terminal device 200. To send to. In addition, the mobile side control unit 230 determines a plurality of pieces of authentication information based on the signal strengths of the plurality of pieces of authentication information included in the request signal received by the mobile side reception unit 210, and the reception time of the authentication information Is recorded for each of the determined authentication information, and the portable-side transmitting unit 220 is caused to transmit an answer signal including information indicating the measured reception time to the in-vehicle device 100. In addition, the in-vehicle side control unit 30 determines whether or not the signal received by the in-vehicle side reception unit 50 includes information indicating the reception time of the authentication information, and information indicating the reception time of the authentication information is included. If included, based on the information indicating the reception time of the authentication information, the signal received by the in-vehicle side reception unit 50 is transmitted by the mobile side transmission unit 220 of the mobile terminal device 200 that is the transmission destination of the request signal. It is determined whether or not the answer signal is transmitted. Thereby, the portable terminal device authentication system 1 in the embodiment can improve the security of authentication.

  Also, according to the mobile terminal device authentication system 1 in the embodiment, when attention is paid to the first authentication information AUD1 and the second authentication information AUD2 as the plurality of authentication information, for example, the first authentication The transmission time TAUD1 of the information for information AUD1 and the reception time TAUD1 # of the first authentication information AUD1 included in the answer signal are compared, and the transmission time TAUD2 of the second authentication information AUD2 is included in the answer signal By comparing the reception time TAUD2 # of the second authentication information AUD2, it is possible to improve the determination accuracy at the time of authentication.

  Further, according to the mobile terminal device authentication system 1 in the embodiment, the signal strength of the request signal can be simplified by setting the frequency at the time of transmission of a plurality of pieces of authentication information based on the resonance characteristics of the transmission antenna 45. Can be changed.

  Moreover, according to the portable terminal device authentication system 1 in the embodiment, the in-vehicle side control unit 30 (communication control unit 32) causes the in-vehicle side transmission unit 40 to transmit a request signal with a transmission time determined randomly. The confidentiality of information is improved and the determination accuracy at the time of authentication can be further increased.

Hereinafter, other embodiments (modifications) will be described.
The mobile terminal device authentication system 1 in the above-described embodiment may be applied to an automobile having a vehicle door such as a passenger car, for example. In this case, when the mobile terminal device 200 is authenticated by the in-vehicle device 100, the locking of the vehicle door may be unlocked.

  In the mobile terminal device authentication system 1 in the above-described embodiment, the signal strength (output) at the time of transmission (transmission) of the authentication information included in the request signal depends on the resonance characteristic of the transmission antenna 45 and the difference in frequency. Although described as a variable, it is not limited to this. For example, the signal strength (or gain) for each piece of authentication information may be varied by a filter circuit or the like in which the resonance characteristics of the transmitting antenna 45 are simulated. The filter circuit may be realized by an analog circuit, a digital circuit, or a combination of these circuits.

  As mentioned above, although the form for implementing this invention was demonstrated using embodiment, this invention is not limited to such embodiment at all, In the range which does not deviate from the summary of this invention, various deformation | transformation and substitution Can be added.

DESCRIPTION OF SYMBOLS 1 ... Portable terminal device authentication system, 6 ... Kick pedal, 7 ... Kick operation part, 8 ... Conversion part, 16 ... Handle lock part, 17 ... Start switch, 18 ... Actuator part, 100 ... In-vehicle apparatus, 20 ... Power supply part, DESCRIPTION OF SYMBOLS 30 ... Car-mounted side control part, 31 ... Start-up control part, 32 ... Communication control part, 33 ... Determination part, 34 ... Drive control part, 35 ... Memory | storage part, 40 ... Car-mounted side transmission part, 50 ... Car-mounted side receiving part, 61 DESCRIPTION OF SYMBOLS ... Drive circuit part 62 ... Input circuit part 63 ... Main switch state acquisition part, 64 ... Main relay drive part, 65 ... Starter drive part, 200 ... Portable terminal device, 210 ... Portable side receiver, 220 ... Portable side transmission , 230... Portable side control unit, 231... Signal strength measuring unit, 232... Reception time measuring unit, 233... Signal generation unit, V... Scooter, E.

Claims (6)

An in-vehicle transmission unit that transmits signals;
A vehicle-side receiving unit for receiving signals;
An in-vehicle device having an in-vehicle side control unit that transmits a request signal to the in-vehicle side transmission unit and determines whether the signal received by the in-vehicle side reception unit is a regular signal;
A mobile-side receiving unit for receiving signals;
A portable transmitter that transmits a signal;
A portable terminal device having a portable side control unit that controls the portable side transmission unit to transmit an answer signal to the request signal in response to the portable side reception unit receiving the request signal;
With
The in-vehicle side control unit causes the in-vehicle side transmission unit to transmit a signal including a plurality of authentication signals having different signal strengths as the request signal,
The mobile-side receiving unit receives the request signal transmitted by the in-vehicle side transmitting unit,
The portable side control unit discriminates the plurality of authentication signals based on signal strengths of the plurality of authentication signals included in the request signal received by the portable side reception unit, and the portable side reception unit The reception time of the authentication signal included in the received request signal is measured for each of the determined authentication signals, and the signal including the information indicating the measured reception time is included in the in-vehicle device, Send it to the mobile side transmitter as an answer signal,
The in-vehicle side control unit determines whether or not the signal received by the in-vehicle side reception unit includes information indicating the reception time of the authentication signal, and the signal received by the in-vehicle side reception unit When the information indicating the reception time of the authentication signal is included, the signal received by the in-vehicle side reception unit based on the information indicating the reception time of the authentication signal is transmitted by the portable side transmission unit. Determine whether it is a transmitted answer signal,
Mobile terminal device authentication system. The in-vehicle side control unit compares the transmission time of the authentication signal and the reception time of the authentication signal, and based on the comparison result, the signal received by the in-vehicle side reception unit is transmitted to the mobile side transmission Determine whether it is an answer signal transmitted by the unit,
The mobile terminal device authentication system according to claim 1. The authentication signal includes a first signal and a second signal having a signal strength smaller than that of the first signal,
The vehicle-mounted side control unit compares the transmission time of the first signal and the reception time of the first signal, and compares the transmission time of the second signal and the reception time of the second signal. Then, based on the comparison result, it is determined whether the signal received by the in-vehicle side receiving unit is an answer signal transmitted by the portable side transmitting unit,
The mobile terminal device authentication system according to claim 2. The vehicle-mounted side control unit causes the request signal to be transmitted to the vehicle-mounted side transmission unit at a transmission time determined randomly.
The portable terminal device authentication system according to any one of claims 1 to 3. An in-vehicle transmission unit that transmits a request signal;
A vehicle-side receiving unit for receiving signals;
A signal including a plurality of authentication signals having different signal strengths is transmitted as the request signal to the in-vehicle side transmission unit, and the signal received by the in-vehicle side reception unit includes information indicating the reception time of the authentication signal Based on the information indicating the reception time of the authentication signal when the signal received by the in-vehicle side reception unit includes the information indicating the reception time of the authentication signal. A vehicle-side control unit that determines whether the signal received by the vehicle-mounted side reception unit is an answer signal for the request signal;
A vehicle-mounted device comprising: A mobile receiver that receives the request signal;
A mobile-side transmitter that transmits an answer signal to the request signal;
Based on signal strengths of a plurality of authentication signals included in the request signal received by the mobile-side receiver, the plurality of authentication signals are discriminated and included in the request signal received by the mobile-side receiver. The reception time of the authentication signal is counted for each of the determined authentication signals, and a signal including information indicating the measured reception time is received with respect to the signal reception source by the mobile-side receiving unit. A portable-side control unit that transmits the signal to the portable-side transmission unit;
A mobile terminal device comprising:

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