JP2017059170A - Mobile terminal device authentication system, on-vehicle device, and mobile terminal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mobile terminal device authentication system, an on-vehicle device, and a mobile terminal device that can improve the operability of authentication processing.SOLUTION: In a mobile terminal device authentication system, an on-vehicle device transmits a signal including a plurality of authentication signals set such that reception signal intensity is different from each other to an on-vehicle side transmission unit, and a mobile terminal device gives an instruction on the reception sensitivity characteristic of a mobile side reception unit on the basis of intensity values of the received authentication signals, and distinguishes the plurality of authentication signals received after the reception sensitivity characteristic of the mobile side reception unit is adjusted to the instructed reception sensitivity characteristic. An on-vehicle side control unit or mobile side control unit determines whether or not the mobile side reception unit has received a normal request signal in communication on the basis of determination results of the plurality of authentication signals.SELECTED DRAWING: Figure 1

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.

The received signal strength varies depending on the distance between the in-vehicle device and the mobile terminal device. When the mobile terminal device is arranged near the in-vehicle device, the received signal of the mobile terminal device may be saturated.
In this regard, when the mobile terminal device receives a signal to be subjected to authentication processing from the in-vehicle device and detects that the reception intensity of a predetermined portion of the signal is saturated, the reception intensity is saturated. There is known a communication system in which an in-vehicle device is notified and the in-vehicle device retransmits at least a predetermined portion of the transmission intensity in response to the notification (see, for example, Patent Document 1).

JP 2014-139552 A

  However, in the conventional technique, when the reception intensity is saturated, by performing the retransmission control, the response of the authentication process may be delayed compared to the case where the retransmission control is not performed, and the operability may be reduced. .

  The present invention has been made in consideration of such circumstances, and an object of the present invention is to provide a mobile terminal device authentication system, an in-vehicle device, and a mobile terminal device that can improve the operability of authentication processing. I will.

The portable terminal device authentication system of the present invention employs the following configuration.
(1) A vehicle-mounted transmitter that transmits a signal, a vehicle-mounted receiver that receives the signal, and a vehicle-mounted transmitter that transmits a request signal and determines the answer signal received by the vehicle-mounted receiver. An in-vehicle device having a side control unit, a portable side receiving unit that receives a signal, a portable side transmitting unit that transmits a signal, and the portable side receiving unit receiving the request signal, the request A portable terminal device that controls the portable transmission unit to transmit an answer signal for the signal, and the in-vehicle control unit has different received signal strengths as the request signal A signal including a plurality of authentication signals set as described above is transmitted to the in-vehicle side transmission unit, and the portable side reception unit can adjust reception sensitivity characteristics by control, and the in-vehicle side transmission unit The portable side control unit instructs the reception sensitivity characteristic of the portable side receiving unit based on the strength value of the authentication signal received by the portable side receiving unit. Then, the plurality of authentication signals received after the reception sensitivity characteristic of the portable side receiving unit is adjusted to the instructed reception sensitivity characteristic, the in-vehicle side control unit or the portable side control unit is Based on the determination results of the plurality of authentication signals, it is determined whether or not the mobile-side receiving unit is a communication that has received a normal request signal.

  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 set so that the received signal strengths are different as the request signal. The portable-side receiving unit can adjust the reception sensitivity characteristic by control, and receives the signal transmitted by the in-vehicle-side transmitting unit as the request signal. The portable side control unit instructs the reception sensitivity characteristic of the portable side reception unit based on the strength value of the authentication signal received by the portable side reception unit, and the portable side reception unit The plurality of authentication signals received after the reception sensitivity characteristic is adjusted are discriminated. The vehicle-mounted side control unit or the mobile side control unit determines whether or not the mobile side reception unit is a communication that has received a normal request signal based on the determination results of the plurality of authentication signals. As a result, the mobile terminal device authentication system can improve the security of authentication.

(2) The portable side control unit instructs a reception sensitivity characteristic of the portable side reception unit based on an intensity value of an authentication signal received by the portable side reception unit, and sets the designated reception sensitivity characteristic to the instructed reception sensitivity characteristic. The plurality of authentication signals received after the reception sensitivity characteristic of the mobile-side receiving unit is adjusted may be determined, and an answer signal including the determination results of the plurality of authentication signals may be transmitted to the mobile-side transmitting unit. .

  According to this configuration, the mobile terminal device authentication system can improve the security of authentication as in the above configuration. Further, the portable terminal device authentication system is instructed by the portable side control unit by instructing a reception sensitivity characteristic of the portable side receiving unit based on an intensity value of an authentication signal received by the portable side receiving unit. The plurality of authentication signals received after the reception sensitivity characteristic of the portable receiver is adjusted to the received sensitivity characteristic, and the answer signal including the determination result of the plurality of authentication signals is determined in the portable transmitter By transmitting to, it is possible to improve the accuracy of identification of a plurality of authentication signals.

(3) The portable side control unit outputs the plurality of authentication signals based on the reception sensitivity characteristic of the portable side receiving unit adjusted based on an intensity value of the authentication signal received by the portable side receiving unit. The plurality of authentication signals may be discriminated based on the intensity value, and the answer signal may be transmitted to the portable-side transmission unit.

  According to this configuration, the mobile terminal device authentication system can improve the security of authentication as in the above configuration. Further, the mobile terminal device authentication system is configured such that the plurality of mobile side receivers receive the plurality of the mobile side receivers based on reception sensitivity characteristics of the mobile side receivers adjusted based on an intensity value of an authentication signal received by the mobile side receivers. By receiving this authentication signal, it is possible to improve the accuracy of identification of a plurality of authentication signals.

(4) The in-vehicle side control unit compares the transmission time of the authentication signal with the determination result of the authentication signal, and based on the comparison result, the signal received by the mobile terminal device is valid. You may make it determine whether it is a request signal.

  According to this configuration, since the mobile terminal device authentication system can compare the transmission time of the authentication signal with the determination result of the authentication signal, the determination accuracy during authentication can be increased.

(5) The authentication signal includes a first signal and a second signal having a signal strength smaller than that of the first signal, and the in-vehicle side control unit is configured to perform the operation based on a first threshold value. The answer signal received by the in-vehicle side reception unit may be determined based on information including the number of times determined as the first signal and the number of times determined as the second signal.

  According to this configuration, the mobile terminal device authentication system can further increase the determination accuracy during authentication by performing signal determination based on the number of times.

(6) The authentication signal includes a first signal and a second signal having a signal strength smaller than that of the first signal, and the portable control unit includes the first signal and the first signal. 2 is discriminated based on a first threshold that can distinguish the second signal and a second threshold that identifies a third signal having a lower signal strength than the second signal, and the first signal Information including the number of times of determination, the number of times determined as the second signal, and the number of times determined as the third signal is information indicating the determination result of the plurality of authentication signals, and the answer signal is Based on information including the number of times determined as the first signal, the number of times determined as the second signal, and the number of times determined as the third signal. Then, the answer signal received by the in-vehicle side receiving unit may be determined.

  According to this configuration, the mobile terminal device authentication system can further increase the determination accuracy during authentication by performing signal determination based on the number of times.

(7) If the on-vehicle side control unit does not determine the second signal, the signal received by the on-vehicle side receiving unit is in an appropriate state with respect to the reception sensitivity characteristic of the portable side receiving unit. If there is a time when it is determined that there is no such second signal, it is determined that the signal received by the in-vehicle side receiving unit is in an appropriate state with respect to the reception sensitivity characteristic of the portable side receiving unit. You may make it do.

  According to this configuration, the mobile terminal device authentication system determines that the signal is the second signal, so that the signal received by the in-vehicle side receiving unit is in an appropriate state with respect to the reception sensitivity characteristic of the mobile side receiving unit. And the determination accuracy at the time of authentication can be further improved.

(8) The in-vehicle side control unit is a request signal in which a signal received by the portable side reception unit is transmitted by the in-vehicle side transmission unit based on a determination result of the plurality of authentication signals included in the answer signal. It may be determined whether or not.

  According to this configuration, the mobile terminal device authentication system determines whether or not the signal received by the mobile-side receiving unit is a request signal transmitted by the in-vehicle-side transmitting unit. The accuracy can be further increased.

(9) The vehicle-mounted side control unit, based on the determination result of the plurality of authentication signals included in the answer signal, receives the signal received by the vehicle-mounted side receiving unit transmitted from the portable side transmitting unit. You may make it determine whether it is a signal.

  According to this configuration, the mobile terminal device authentication system determines whether or not the signal received by the in-vehicle side reception unit is the answer signal transmitted by the mobile side transmission unit. Can be further improved.

(10) The in-vehicle side control unit may cause the in-vehicle side transmission unit to transmit the authentication signal having a transmission time irregularly determined from predetermined patterns.

  According to such a configuration, the mobile terminal device authentication system can improve the security of authentication by using, for the authentication process, an authentication signal having a transmission time irregularly determined from predetermined patterns. it can.

The on-vehicle apparatus of the present invention employs the following configuration.
(11) The in-vehicle side transmission unit that transmits a request signal to the mobile terminal device, the in-vehicle side reception unit that receives the signal, and the in-vehicle side transmission unit that transmits the request signal, the request signal is received by the mobile terminal device An in-vehicle side control unit that determines an answer signal, and the in-vehicle side control unit outputs, as the request signal, a signal including a plurality of authentication signals set so that received signal strengths are different from each other. The in-vehicle side receiving unit adjusts the reception sensitivity characteristic of the mobile terminal device based on the strength value of the authentication signal received by the mobile terminal device, and adjusts the reception sensitivity characteristic of the mobile terminal device. After receiving the signal including the result of the determination of the plurality of authentication signals received by the portable terminal device, the in-vehicle side control unit receives the signal by the in-vehicle side reception unit. Whether the signal received by the mobile terminal device is a legitimate request signal from the answer signal received by the in-vehicle receiving unit based on the determination result of the plurality of authentication signals included in the received signal Judgment was made.

  According to this configuration, the reception sensitivity characteristic of the mobile terminal device is adjusted based on the strength value of the authentication signal, and the plurality of authentication signals received by the mobile terminal device after the reception sensitivity characteristic of the mobile terminal device is adjusted. By receiving the signal including the result of the signal determination by the in-vehicle side reception unit, the in-vehicle side control unit is based on the determination results of the plurality of authentication signals included in the signal received by the in-vehicle side reception unit. From the answer signal received by the in-vehicle side receiving unit, it can be determined whether or not the signal received by the mobile terminal device is a regular request signal.

The portable terminal device of the present invention employs the following configuration.
(12) A portable-side receiver that receives a request signal from the in-vehicle device, a portable-side transmitter that transmits a signal, and an answer to the request signal in response to the portable-side receiver receiving the request signal. A portable-side control unit that controls the portable-side transmission unit to transmit a signal, and the portable-side reception unit is capable of adjusting a reception sensitivity characteristic by control, and transmitted by the in-vehicle device. Receiving the request signal, the portable side control unit instructing a reception sensitivity characteristic of the portable side receiving unit based on an intensity value of the authentication signal received by the portable side receiving unit; A plurality of authentication signals received after the reception sensitivity characteristic of the mobile-side receiving unit is adjusted to the characteristic are discriminated.

  According to this configuration, the portable side control unit instructs the reception sensitivity characteristic of the portable side receiving unit based on the strength value of the authentication signal received by the portable side receiving unit, and the instructed reception sensitivity characteristic In addition, the plurality of authentication signals received after the reception sensitivity characteristic of the mobile-side receiving unit is adjusted can be determined.

  ADVANTAGE OF THE INVENTION According to this invention, the portable terminal device authentication system which can improve the operativity of an authentication process, a vehicle-mounted apparatus, and a portable terminal device can be provided.

It is a block diagram which shows the portable terminal device authentication system 1 which concerns on this embodiment. 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. It is a figure which shows an example of the transmission pattern information table which memorize | stores a transmission pattern. 6 is a flowchart illustrating an example of a process flow of a portable control unit 230. It is a figure explaining the signal measurement process of the portable side control part 230 in step S220. It is a flowchart which shows an example of the flow of a signal measurement process. 4 is a timing chart illustrating an example of operation timing of each unit of the in-vehicle side control unit 30. It is explanatory drawing which shows the frame structure of the answer signal transmitted by RF communication of this embodiment. It is a figure (the 1) which shows the effect by the portable terminal device authentication system 1 of this embodiment. It is FIG. (2) which shows the effect by the portable terminal device authentication system 1 of this embodiment. It is a flowchart which shows the procedure of the measurement range setting process of the portable terminal device 200 of the modification of this embodiment.

  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 according to the present embodiment. 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 the plurality of pieces of authentication information included in the request signal, 3 of the first authentication information, the second authentication information, and the third authentication information. Although the type will be described as a representative, the authentication information is not limited to only this information. For example, fourth authentication information may be included. The authentication information is an example of an “authentication signal”. The first authentication information, the second authentication information, and the third authentication information are examples of “first signal”, “second signal”, and “third signal”.

  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 determination unit 33 determines that 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 in-vehicle side receiving unit 50 Device (in this case, the mobile terminal device 200) is determined to be a predetermined regular device, and it is determined that the authentication is successful.

  On the other hand, when the determination unit 33 cannot determine that the signal received by the in-vehicle side reception unit 50 is the answer signal transmitted by the mobile terminal device 200 that is the transmission destination of the request signal, It is determined that the receiving device 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. Note that the mobile-side receiving unit 210 may be configured to have sensitivity characteristics (directivity) with a plurality of different directions as axes.

  The portable side control unit 230 includes, for example, a signal strength measurement unit 231, a signal determination unit 232, a signal generation unit 233, and a reception control unit 234. The signal strength measuring unit 231 measures the signal strength of the request signal received by the mobile-side receiving unit 210. When the mobile-side receiving unit 210 has sensitivity characteristics with a plurality of different directions as axes, the signal strength measuring unit 231 may measure the signal strength detected for each of the plurality of axes for each axis. .

  The signal determination unit 232 determines the request signal received by the mobile-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. The reception control unit 234 controls the request signal transmitted by the in-vehicle device 100 to be receivable based on the result received by the mobile-side receiving unit 210. When the mobile-side receiving unit 210 has sensitivity characteristics with a plurality of different directions as axes, the signal determination unit 232 uses the signal strength measurement unit 231 to measure the signals detected for each of the plurality of axes. May be arranged, and the value of the measurement result after the arrangement may be determined.

  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 vehicle-mounted side transmission part 40 is provided with the drive part 41 and the resonance part 42, for example.
The drive unit 41 amplifies the power of the signal supplied from the in-vehicle side control unit 30 and drives the resonance unit 42. The resonating unit 42 includes a transmitting antenna 43 and a capacitor 44. The transmitting antenna 43 includes a coil and forms, for example, an LC type resonance circuit together with the capacitor 44. The resonance part 42 illustrated in the figure is configured as a series resonance circuit. The resonance frequency of the resonance unit 42 is indicated by f0. The transmitting antenna 43 radiates radio waves generated by the resonance of the resonance unit 42 into the atmosphere.

  The vehicle-mounted side transmission part 40 comprised as mentioned above functions as a band pass filter which makes resonance frequency f0 a center frequency. For example, the signal supplied from the in-vehicle side control unit 30 to the in-vehicle side transmission unit 40 may be a digital signal having a predetermined frequency f near the resonance frequency f0, and the waveform is configured as a rectangular pulse signal sequence. May be. The resonance unit 42 attenuates components other than the desired band having the resonance frequency f0 as the center frequency, and also has the smallest attenuation rate at the resonance frequency f0 in the signal pass band, and the attenuation rate as the frequency increases from the resonance frequency f0. Has a frequency characteristic that increases. Note that the frequency components in the band other than the desired band include harmonic components having the resonance frequency f0 as the fundamental frequency, and the frequency component in the band other than the desired band is the frequency of the in-vehicle transmission unit 40. It is attenuated due to characteristics.

  The in-vehicle side control unit 30 generates a signal DMOD for generating a signal of a modulation method such as ASK (amplitude-shift keying) or PSK (phase-shift keying), and sends the signal DMOD to the in-vehicle side transmission unit 40. Supply. The signal DMOD includes a pulse signal train having a frequency f. For example, the communication control unit 32 controls the frequency division ratio with respect to a clock signal having a frequency sufficiently higher than the frequency f of the signal DMOD, adjusts the frequency f of the signal DMOD so as to be a desired frequency, and performs an authentication signal. Is generated. A method for controlling the frequency f of the signal DMOD for generating the authentication signal will be described later.

  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 signal received by the reception antenna 211, noise removal, offset adjustment, filtering processing, and the like, and outputs the result to the mixer 214. For example, the reception circuit unit 212 includes an offset measurement unit 216 and a variable gain amplification unit (hereinafter referred to as VGA) 217. The VGA 217 amplifies the signal with a gain according to the control. The signal amplified by the VGA 217 may be, for example, a signal generated from a signal received by the receiving antenna 211 and a signal whose offset is measured by the offset measuring unit 216. The VGA 217 amplifies the signal generated from the signal received by the receiving antenna 211 with a desired gain, and adjusts the power level to be supplied to the mixer 214. The offset measurement unit 216 measures the offset of the signal that the VGA 217 amplifies with a desired gain.

  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 demodulator 215 demodulates the signal output from the mixer 214 with respect to the modulation scheme of the vehicle-mounted transmitter 40 described above, and outputs the demodulated signal to the portable controller 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 synchronization pattern SYNC1, and identification information IDk. The authentication information includes first authentication information AUD1, second authentication information AUD2, and third information. Authentication information AUD3. 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 training data TD is sometimes referred to as a preamble.

  The synchronization pattern SYNC1 is arranged to be transmitted next to the training data TD, for example. The synchronization pattern SYNC1 includes a signal pattern used as an index for extracting various types of information after the mobile-side receiving unit 210 finishes training with 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, the second authentication information AUD2, and the third authentication information AUD3 included in the pattern LFP indicate, for example, information (encryption key, ciphertext, etc.) required for the authentication process. . A general algorithm can be applied to the authentication processing method. In the authentication process, the information encrypted in the in-vehicle device 100 is decrypted by the mobile terminal device 200, and the decrypted information is determined by either the mobile terminal device 200 or the in-vehicle device 100. Good. In the following embodiment, a case where information necessary for authentication processing is added to the amplitude of the signal of each part of the first authentication information AUD1, the second authentication information AUD2, and the third authentication information AUD3 is illustrated. To do.

(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, when the activation switch 17 is on, the communication control unit 32 refers to the transmission pattern information table (FIG. 6) and sets the request signal transmission pattern (step S102).

  The information that defines the transmission pattern includes information such as the frequency at which authentication information is transmitted and the time at which authentication information is transmitted.

  For example, as the frequency f for transmitting the authentication information, the frequency f1 for transmitting the first authentication information AUD1, the frequency f2 for transmitting the second authentication information AUD2, and the third authentication information The frequency f3 for sending AUD3 is defined. The communication control unit 32 sets the frequency f1, the frequency f2, and the frequency f3 based on the frequency characteristics (hereinafter referred to as “resonance characteristics”) with respect to the gain (signal strength) of the transmitting antenna 45 described above. . 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. For example, the frequency f3 is set to a value farther than the frequency f2 with respect to the resonance frequency f0 of the transmission antenna 45 described above. When the same power is supplied to the transmission antenna 45 by arranging the frequency f1, the frequency f2, and the frequency f3 side by side as described above, the transmission power transmitted as radio waves of the respective frequencies The frequency f1 becomes the highest, and then decreases in the order of the frequency f2 and the frequency f3.

  The communication control unit 32 can easily change the signal strength of the request signal by adjusting the frequency at the time of sending each piece of authentication information, and the radio wave when the first authentication information AUD1 is sent. The request signal is transmitted by making the signal strength different from the signal strength of the radio wave when the second authentication information AUD2 is sent and the signal strength of the radio wave when the third authentication information AUD3 is sent. can do.

  Next, the communication control unit 32 transmits a request signal (Step S104). For example, the communication control unit 32 transmits the request signal request signal according to any of a plurality of predetermined transmission patterns.

  For example, the communication control unit 32 sets a time TAUD1 for sending the first authentication information AUD1, a time TAUD2 for sending the second authentication information AUD2, and a time TAUD3 for sending the third authentication information AUD3. A prescribed transmission pattern is determined in advance and stored in the storage unit 35. FIG. 6 is a diagram illustrating an example of a transmission pattern information table that stores transmission patterns. The transmission pattern information table transmits a time TAUD1 for sending the first authentication information AUD1, a time TAUD2 for sending the second authentication information AUD2, and a time TAUD3 for sending the third authentication information AUD3. Remember time (milliseconds). For example, when the transmission control unit 32 selects a transmission pattern from the transmission pattern information table, the communication control unit 32 randomly determines the transmission pattern using a random number or the like. At this time, the values of the time TAUD1, the time TAUD2, and the time TAUD3 may be the same or different. Accordingly, the communication control unit 32 can improve the confidentiality of information regarding the time TAUD1, the time TAUD2, and the time TAUD3.

  The communication control unit 32 stores information on the determined time TAUD1, time TAUD2, and time TAUD3 in the storage unit 35. When the time TAUD1, time TAUD2, and time TAUD3 are set again, for example, the communication control unit 32 stores them last time. The information of the time TAUD1, time TAUD2, and time TAUD3 set this time is overwritten on the information. That is, the communication control unit 32 updates the information on the time TAUD1, the time TAUD2, and the time TAUD3 in the storage unit 35 every time the time TAUD1, the time TAUD2, and the time TAUD3 are set.

  Further, the communication control unit 32 transmits a request signal having a frame structure as shown in FIG. 4 to the mobile terminal device 200, for example. The communication control unit 32 sets the frequency of the signal to be output to a predetermined frequency, and causes the in-vehicle side transmission unit 40 to transmit the mobile terminal device information.

Further, the communication control unit 32 sets the frequency of the signal to be output to the frequency f1, and causes the in-vehicle side transmission unit 40 to transmit the first authentication information AUD1 over the time TAUD1.
In addition, the communication control unit 32 sets the frequency of the signal to be output to the frequency f2, and causes the in-vehicle side transmission unit 40 to transmit the second authentication information AUD2 over time TAUD2.
Further, the communication control unit 32 sets the frequency of the signal to be output to the frequency f3, and causes the in-vehicle side transmission unit 40 to transmit the third authentication information AUD3 over the time TAUD3.

  The communication control unit 32 transmits a request signal to the mobile terminal device 200 based on the transmission frequency (frequency f1, f2, f3) and the transmission time (time TAUD1, TAUD2, TAUD3) set in this way.

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

  On the other hand, when the answer signal is received by the in-vehicle side receiving unit 50, the determination unit 33 is information included in the answer signal received by the in-vehicle side receiving unit 50, and shows the result of receiving the authentication information. From the information shown, it is determined whether or not the number of differential signal detections (difference signal detection count) is zero (step S110). The difference signal in the above case is the second authentication information AUD2 or the third authentication information AUD3 with respect to the first authentication information AUD1, and the received signal strength (signal) of the first authentication information AUD1 This is a signal excluding signals whose received signal strength (signal strength value) is less than or equal to a predetermined amount compared to the intensity value) and which are treated as invalid signals whose received signal strength (signal strength value) is small. is there.

  The determination unit 33 determines whether or not the determination condition is satisfied based on the information of the signal received by the in-vehicle side reception unit 50 (step S112). The determination condition is, for example, whether or not the mobile terminal device 200 that is the communication partner of the in-vehicle side receiving unit 50 is a legitimate device, and from the answer signal received from the mobile terminal device 200, the mobile terminal device 200. Is a condition used as a criterion for determining whether or not the received signal is a regular request signal. For example, when the determination condition is satisfied, the determination unit 33 determines that the signal received by the mobile terminal device 200 is a normal request signal and that the mobile terminal device 200 that has sent the answer signal is a normal device. Then, it is determined that the mobile terminal device 200 has been successfully authenticated. As an example of the determination condition, “when the number of detected invalid signals is zero” or “the number of times determined with respect to the time at which the first authentication information AUD1 was sent, and the first authentication” The case where the number of times that the received signal strength of the usage information AUD1 is determined to be equal to the received signal strength coincides.

  When the determination unit 33 satisfies the above determination conditions, 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. In conjunction with this determination, whether the portable device ID information included in the answer signal matches, whether the RSSI strength (reception strength of the first authentication information AUD1) is equal to or greater than a predetermined threshold, and for encryption by decrypting the encryption data When each situation such as whether the data matches can be detected, the determination unit 33 determines that the mobile terminal device 200 that is the communication partner of the in-vehicle side reception unit 50 is a legitimate device and succeeds in the authentication. (Step S114).

  On the other hand, if the determination unit 33 has a difference signal detection count (difference signal detection count) of 1 or more, or if the determination condition is not satisfied, the signal received by the in-vehicle side reception unit 50 is: It is determined that the answer signal is not 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. 7 to FIG. 11, the processing of the portable control unit 230 of the present embodiment will be described.

FIG. 7 is a flowchart illustrating an example of a process flow of the mobile-side control unit 230.
First, the mobile-side control unit 230 performs a request signal reception process. In the request signal reception process, the reception sensitivity characteristic of the mobile-side receiving unit 210 of the mobile terminal device 200 is optimized. As the request signal reception process, for example, the mobile-side control unit 230 determines whether or not the mobile-side reception unit 210 has started receiving a request signal (step S205). If reception of the request signal is not started by the mobile-side receiving unit 210, the process of this flowchart is terminated.

  On the other hand, the signal determination unit 232 determines whether reception of the first authentication information AUD1 is started in the frame structure (pattern LFP) of the request signal when reception of the request signal is started by the mobile-side receiving unit 210. That is, it is determined whether or not the period of the mobile terminal device information (LF data) has ended in the frame structure of the request signal (step S210).

  For example, the signal determination unit 232 starts counting the time when the reception of the request signal is started, that is, in the frame structure of the request signal, in response to the start of the information for the mobile terminal device. It is determined that the period of the mobile terminal device information (LF data) has ended due to the expiration of the period.

  The signal determination unit 232 waits until the LF data period of the request signal expires. On the other hand, after the LF data period of the request signal expires, the portable control unit 230 performs signal measurement processing. Details of the signal measurement process will be described later (step S220).

  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 the response signal (step S230). Thereby, the process of this flowchart is complete | finished.

FIG. 8 is a diagram for explaining the signal measurement process of the portable control unit 230 in step S220. The figure shows a request signal received by the mobile terminal device 200 that is the target of the signal measurement process.
A description will be given of processing performed in a period from time t0 to time t7 when the first authentication information AUD1, the second authentication information AUD2, and the third authentication information AUD3 are observed in the request signal. The mobile-side control unit 230 performs a plurality of measurements during a period from time t0 to time t7. For example, in the following description, as shown in the figure, a case where measurement is performed in six steps from M1 to M6 will be described as an example. The measurement is performed at each time from time t1 to time t6 measured with reference to time t0. From the time t1 to the time t6, the time from the time t0 to the time t1 is defined as the time T1, and the time after the time t1 is defined as the period T2.

  FIG. 8A shows a schematic signal waveform. The amplitudes of the first authentication information AUD1, the second authentication information AUD2, and the third authentication information AUD3 are observed at W1, W2, and W3. When each of the first authentication information AUD1, the second authentication information AUD2, and the third authentication information AUD3 is received as a prescribed signal, the relationship is W1> W2> W3.

  FIG. 8B shows the detected amplitude value detected in each measurement. The detected value of the measurement time M1 at time t1 and the measurement time M2 at time t2 is W1. The detected value of the measurement time M3 at time t3 and the measurement time M4 at time t4 is W2. The detected value of the measurement time M5 at time t5 and the measurement time M6 at time t6 is W3. Based on the detection value W1 of M1, the first threshold value TH1 and the second threshold value TH2 are determined so that the relationship represented by the following formula (1) is established.

TH1 = (W1-d1)
TH2 = (W1-d2)
W3 <TH2 <W2 <TH1 <W1 (1)

  In the above formula (1), d1 and d2 are predetermined as constants, and for example, the values are stored in the storage unit of the mobile terminal device 200 (not shown). In the following description, d1 is referred to as a differential threshold value (first threshold value) that can identify a signal (second signal) having a detection value W2 having a smaller amplitude than the signal (first signal) having a detection value W1, and d2 The signal of the detection value W3 (third signal) having an amplitude smaller than the detection value W2 is referred to as an identifiable invalid threshold (second threshold).

  FIG. 9 is a flowchart illustrating an example of the flow of signal measurement processing.

  The portable-side control unit 230 counts the number of measurements using a measurement number counter that takes values from 0 to 6. The portable-side control unit 230 counts the number of measurement times when the measured value is detected as (TH1 <W1) using a normal signal detection number counter that takes values from 1 to N1. The portable side control unit 230 counts the number of measurement times when the measured value is detected as (TH2 <W2 <TH1) using a differential signal detection number counter that takes values from 0 to N2. The portable-side control unit 230 counts the number of measurement times when the measured value is detected as (W3 <TH2) using an invalid signal detection number counter that takes values from 0 to N3. The “normal signal detection number counter”, “difference signal detection number counter”, and “invalid signal detection number counter” are defined as variables. For example, these values are stored in the storage unit of the mobile terminal device 200 (not shown). Stored in the area. For example, each of “measurement number counter”, “normal signal detection number counter”, “difference signal detection number counter”, and “invalid signal detection number counter” is set to 0, 1, 0, and 0 by initialization processing. Is done.

  First, the portable control unit 230 determines whether or not the current measurement is the first time based on the value of the measurement number counter. For example, the portable control unit 230 determines whether or not the value of the measurement number counter is 1 (step S402).

  If it is determined by the determination in step S402 that the current measurement is the first measurement, the reception control unit 234 uses the offset measurement unit 216 to execute the request signal frame before performing the first measurement described later. In the structure (pattern LFP), the offset of the signal corresponding to the first authentication information AUD1 is measured. If the measured offset value is not within the predetermined range, the reception control unit 234 controls the offset measuring unit 216 so that the offset value falls within the predetermined desired range. Adjust. The reception control unit 234 finishes the adjustment when the measured offset value measured again falls within a predetermined range, and fixes the adjusted value until the following series of processing is finished after the adjustment is finished. . The reception control unit 234 stores the adjusted offset measurement value data in a storage unit (not shown) (step S404).

The reception control unit 234 determines a measurement range suitable for receiving each piece of authentication information in order to adjust the reception sensitivity characteristic of the mobile-side reception unit 210. For example, the portable receiver 210 has a VGA 217, and the amplification factor of the portable receiver 210 can be set to a desired amplification factor by adjusting the amplification factor of the VGA 217. In other words, the reception control unit 234 controls the VGA 217 to function as an AGC (Automatic Gain Control), and obtains an amplification factor that optimizes the output signal level of the VGA 217 by the function of the AGC. Note that the amplification factor obtained as a result of the optimization takes a quantized discrete value. As the amplification factor, for example, 54 dB (decibel), 36 dB, 18 dB, 0 dB, and −18 dB are set in order from the highest amplification factor. The reception control unit 234 measures the signal level of the output signal of the VGA 217 while adjusting the amplification factor of the VGA 217 to the above value, and optimizes the amplification factor of the VGA 217 so that the measured signal level is within a desired range. To do. In addition, when the variable range covers a wide range as described above, the VGA 217 may be divided into a plurality of stages, or may be switched corresponding to a plurality of systems.
As described above, the reception control unit 234 adjusts the amplification factor of the VGA 217 so that the amplification factor is suitable for the optimized measurement range. And the measurement range of the portable receiver 210 is set (step S406).

The signal strength measuring unit 232 obtains a received signal strength value (RSSI ₁ ) by measuring the received signal strength of the signal corresponding to the first authentication information AUD1 as the strength value of the authentication signal. Note that RSSI ₁ is used as a reference value for the determination process of the measurement time in the subsequent measurement times (step S408). For example, RSSI ₁ corresponds to the measured value W1 at M1 in FIG.

  The reception control unit 234 adds 1 to the value of the normal signal detection number counter, updates the value after the addition, writes the updated value in the normal signal detection number counter (step S410), and performs step S424. Proceed to processing.

When it is determined in step S402 that the number of measurement times is the second time or more, the signal strength measurement unit 232 uses the received signal strength of the signal corresponding to the authentication information AUD corresponding to the measurement time as the strength value of the authentication signal. Is measured to obtain a received signal strength value (RSSI _N ) (step S412).
The signal determination unit 232 determines whether or not the detected signal should be determined as an invalid signal based on the invalid threshold d2 determined from RSSI ₁ acquired in step S412 (step S414).
If it is determined in step S414 that the detected signal is an invalid signal, the reception control unit 234 adds 1 to the counter value of the invalid signal detection count, and updates the value after the addition, The updated value is written in the invalid signal detection number counter (step S416), and the process proceeds to step S424.

On the other hand, if the detected signal is not determined to be an invalid signal in the determination in step S414, the reception control unit 234 acquires the RSSI ₁ acquired in step S408 of the first measurement time obtained by the signal determination unit 232. When the difference between the RSSI _N obtained in step S412 of the current measurement count and determines whether or difference threshold value. For example, the reception control unit 234 determines whether or not the detected signal should be determined as a differential signal based on the difference threshold d1 determined from RSSI ₁ acquired in step S412 (step S418).

In the determination of step S418, the difference between the RSSI ₁ and RSSI _N is, when it is determined to be equal to or greater than the difference threshold, the reception control unit 234 adds 1 to the value of the differential signal detection number counter, the The value after the addition is updated, the updated value is written in the difference signal detection number counter (step S420), and the process proceeds to step S424.

On the other hand, in the judgment of step S418, the difference between the RSSI ₁ and RSSI _N is, when it is determined not more than the difference threshold, the reception control unit 234 adds 1 to the normal signal detection times, after the addition The value is updated, and the updated value is written in the normal signal detection number counter (step S422), and the process proceeds to step S424.

  After completion of any of the processing of step S410, step S416, step S420, or step S422, the reception control unit 234 adds 1 to the number of measurements, updates the value after the addition, and after the update Is written in the measurement counter (step S424).

  The reception control unit 234 determines whether or not the specified number of measurements has been completed based on the value of the measurement number counter (step S426).

  If it is determined in step S426 that the specified number of measurements have been completed, the measurement for the request signal is terminated (step S428). Thereby, the process of this flowchart is complete | finished.

  On the other hand, if it is determined in step S426 that the specified number of measurements has not been completed, the measurement for the request signal is continued (step S430). Thereby, the process of this flowchart is complete | finished.

  With reference to FIG. 10, the process of the portable terminal device authentication system 1 will be described. FIG. 2 is a timing chart showing an example of the processing flow of the mobile terminal device authentication system 1.

  In the figure, (a) start switch, (b) control unit start, (c) control unit initialization process, (d) main switch, (e) main switch determination value, (f) LF transmission, (g) Each state of portable device processing, (h) RF reception, (i) RF data determination, (j) solenoid control, and (k) unlocking is shown.

  At time t <b> 10, when the operation of the activation switch 17 is detected (0 V), activation of the control unit is instructed to the in-vehicle control unit 30 (“control unit activation: ON (ON)”). In response to this instruction, the in-vehicle control unit 30 performs initialization processing and ends by time t15. 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 The state where the (main switch judgment value) is turned off is continued.

  The in-vehicle side control unit 30 sequentially transmits LF signals for “smart authentication communication” corresponding to the portable device registered in the in-vehicle side control unit 30 as follows.

At time t21, the in-vehicle device 100 starts transmitting a request signal and ends the transmission at time t22. Between the time t21 and the time t22, the mobile terminal device 200 requests, for example, a request including a set of signals of the first authentication information AUD1, the second authentication information AUD2, and the third authentication information AUD3. Send a signal.
The mobile terminal device 200 receives the request signal. By this reception, the mobile terminal device 200 adjusts the reception sensitivity characteristic according to the signal strength of the signal extracted from the received request signal.

Between time t21 and time t22, the mobile terminal device 200 receives a request signal including signals of the first authentication information AUD1, the second authentication information AUD2, and the third authentication information AUD3, for example. Send.
The mobile terminal device 200 receives the request signal and performs an authentication process based on the request signal. In the authentication process, for example, an authentication process is performed using difference information of signal strength values of the first authentication information AUD1, the second authentication information AUD2, and the third authentication information AUD3. For example, the mobile terminal device 200 stores information on the number of times shown in the transmission pattern information table shown in FIG. 6 above, and when detecting the number of times corresponding to the pattern, a request (request) from the in-vehicle device 100 is stored. ) May be authenticated for the mobile terminal device 200. As a result of the authentication process, when the request from the in-vehicle device 100 is authenticated to the mobile terminal device 200, the mobile terminal device 200 transmits an answer signal (RFA) from the mobile terminal device 200 after time t22. Start. The in-vehicle device 100 receives the answer signal (RFA) transmitted by the in-vehicle side receiving unit 50.

  At time t23, the in-vehicle device 100 performs authentication (RF data determination) of the mobile terminal device 200 based on the received answer signal (RFA). For example, the authentication of the mobile terminal device 200 may halve whether or not the received answer signal (RFA) matches the one specified as the regular answer signal. When the authentication of the mobile terminal device 200 is successful (time t24), the in-vehicle device 100 causes the in-vehicle side control unit 30 (drive control unit 34) to drive the solenoid of each unit to unlock the locked state of each unit. Control. The locking state of each part is unlocked after time t25.

(Answer signal frame structure)
FIG. 11 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 the figure, for example, the pattern RFA indicates in-vehicle device information, information indicating the number of receptions NAUD1 # of the first authentication information AUD1, and the number of receptions NAUD2 # of the second authentication information AUD2. Information, information indicating the number of receptions NAUD3 # of the third authentication information AUD3, error correction information ECC2, and the like. The in-vehicle device information includes at least training data TD, a synchronization signal SYNC2, and identification information. 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 synchronization signal SYNC2 is arranged to be transmitted next to the training data TD, for example. The synchronization signal SYNC2 includes a signal pattern used as an index when extracting various types of information after the in-vehicle side receiving unit 50 finishes training with 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 number of receptions NAUD1 # 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.

  The information indicating the number of receptions NAUD1 # of the first authentication information AUD1, the information indicating the number of receptions NAUD2 # of the second authentication information AUD2, and the number of receptions NAUD3 # of the third authentication information AUD3 are shown. Information such as information may be assigned to a part of the pattern RFA in association with other information. For example, information indicating the number of receptions NAUD1 # of the first authentication information AUD1 may be associated with the received signal strength of the first authentication information AUD1. At this time, the information indicating the number of receptions NAUD1 # of the first authentication information AUD1 and the information indicating the number of reception signal strengths NAUD1 # of the first authentication information AUD1 are multiplied by a predetermined coefficient and linearly added. Can be made into one piece of information. As described above, by using one piece of information, a lot of information can be transmitted as a short frame length pattern without individually assigning each piece of information to the pattern RFA. The above is the first authentication information AUD1, but the same applies to the second authentication information AUD2 and the third authentication information AUD3.

  The determination unit 33 of the in-vehicle device 100 receives the number of receptions NAUD1 # of the first authentication information AUD1 and the number of receptions of the second authentication information AUD2 from an answer signal having a frame structure (RFA) as shown in FIG. The NAUD2 # and the number of times of receiving the third authentication information AUD3 NAUD3 # are acquired. The determination unit 33 includes, for example, the number of times determined as a “normal” signal (first signal) and the number of times determined as a “difference signal (second signal)” based on the difference threshold (first threshold). Based on the information, it is determined from the answer signal received by the in-vehicle side receiving unit 50 whether or not the signal received by the mobile terminal device 200 is a regular request signal. Based on the information including the number of times determined as “normal” signal (first signal) and the number of times determined as “difference signal (second signal)” by this determination, the signal is received by the in-vehicle side receiving unit 50. It can be determined that the received signal is a normal answer signal.

12 and 13 are diagrams showing the effects of the mobile terminal device authentication system 1. FIG. The graphs shown in FIG. 12 and FIG. 13 show the measurement results of the signal strength of the set of signals detected in the mobile terminal device 200 by changing the distance between the in-vehicle device 100 and the mobile terminal device 200. FIG. 12 shows an example in which the reception sensitivity characteristic of the mobile terminal device 200 is determined so that the in-vehicle device 100 can be unlocked from the mobile terminal device 200 located relatively far away. As shown in this figure, the graphs indicated by W1 to W3 indicate the reception strengths of the first authentication information AUD1, the second authentication information AUD2, and the third authentication information AUD3, respectively. In the range of about 40 (cm) to 250 (cm), W1 to W3 are separated, and it can be seen that a difference in signal intensity can be detected. By defining the reception sensitivity characteristic of the mobile terminal device 200 so as to correspond to the signal intensity shown in this figure, the above authentication method can be applied without adjusting the reception sensitivity characteristic.
However, in the range of about 40 (cm) or less, the reception level is saturated and W1 and W3 cannot be separated and received.

  FIG. 13 shows a measurement result when the reception sensitivity characteristic of the mobile terminal device 200 is adjusted with respect to the measurement conditions of FIG. In the measurement condition of the measurement result shown in FIG. 13, the reception sensitivity of the mobile terminal device 200 is reduced from the measurement condition in the case of FIG. As a result, the results shown in FIG. 12 indicate that the signals can be separated and received within a range of about 40 (cm) or less where W1 to W3 were not separated.

  Thus, in the case of the mobile terminal device authentication system 1, the first authentication information used as the authentication signal is adjusted by adjusting the reception sensitivity characteristic of the mobile terminal device 200 based on the intensity of the actually received signal. AUD1, second authentication information AUD2 and third authentication information AUD3 can be received as signals having different signal strengths.

  According to the above embodiment, the in-vehicle side control unit 230 causes the in-vehicle side transmission unit 40 to transmit a signal including a plurality of authentication signals set so that the received signal strength (RSSI) is different as the request signal, The portable side receiving unit 210 receives the signal transmitted by the in-vehicle side transmitting unit 40 as a request signal, and the portable side control unit 230 is based on the strength value of the authentication signal received by the portable side receiving unit 210. The reception sensitivity characteristic of the reception unit 210 is instructed, and a plurality of authentication signals received after the reception sensitivity characteristic of the mobile-side reception unit 210 is adjusted to the instructed reception sensitivity characteristic are determined. The answer signal including the determination result is transmitted to the mobile-side transmission unit 220, and the in-vehicle side control unit 30 determines the determination results of the plurality of authentication signals included in the signal received by the in-vehicle side reception unit 50. Based on the answer signal received by the in-vehicle side receiving unit 50, it is possible to improve the security of authentication by determining whether the signal received by the mobile terminal device is a legitimate request signal. .

(First Modification of Embodiment)
Hereinafter, a first modification of the embodiment will be described.
Although the mobile terminal device 200 of the above-described embodiment has received the reception signal by a single system, the mobile terminal device 200 of the first modification example receives the reception signal by a plurality of systems. Hereinafter, this point will be mainly described.

  The mobile-side receiving unit 210 includes a plurality of antennas (not shown), and separately detects signals from the respective antennas. Each antenna is assigned to an individual system (channel). Each of the plurality of antennas has directivity characteristics with independent reception sensitivity. For example, the directivity axis of each antenna is determined so that the sensitivity increases in different directions. For example, the directivity axes of the three antennas are determined to be orthogonal to each other, and the antennas are supported so that the axes of the antennas are fixed to the main body of the mobile terminal device 200. The above three antennas are allocated to three channels (ch1, ch2, ch3).

  The mobile-side receiving unit 210 detects the signal from each antenna separately for each channel, and makes it possible to individually determine the received signal strength of each channel.

  The portable side control unit 230 instructs the reception sensitivity characteristic of the portable side receiving unit 210 based on the strength value of the authentication signal received by the portable side receiving unit 210 separately for each channel. The portable control unit 230 determines a plurality of authentication signals received after the reception sensitivity characteristic of the portable reception unit 210 is adjusted to the instructed reception sensitivity characteristic.

  If it is said 1st modification, the probability which detects a request signal can be raised by determining the signal for an authentication which isolate | separated and received for every channel which each allocated the received signal to the some system | strain.

(Second Modification of Embodiment)
Hereinafter, a second modification of the embodiment will be described. The mobile terminal device 200 of the first modified example receives a received signal by a plurality of systems, but the mobile terminal device 200 of the second modified example receives a received signal by a plurality of systems. This simplifies the configuration. Hereinafter, this point will be mainly described.

If the reception is performed by simply separating each channel, the configuration of the mobile terminal device 200 becomes complicated. Therefore, in order to simplify the configuration of the mobile terminal device 200 according to the present modification, for example, the signal from each antenna is detected separately for each channel, and the amplification factor of the signal of each channel is set to a desired value. Although it arranges, it is comprised so that the authentication signal of each channel after amplification can be discriminated individually.
Similarly to the above embodiment and the first modification, the reception control unit 234 can select any one of the plurality of measurement ranges. For example, in the following description, it is assumed that there are two selectable measurement ranges. The two measurement ranges are a first measurement range suitable for authentication of the mobile terminal device 200 arranged at a relatively long distance and a second measurement range suitable for authentication of the mobile terminal device 200 arranged at a relatively short distance. It is. The first measurement range and the second measurement range are different in the range of received power of radio waves received by the mobile terminal device 200.
The reception control unit 234 selects one of the plurality of measurement ranges as a measurement range common to each channel, and causes the reception sensitivity characteristic of the mobile-side reception unit 210 to correspond to the selected measurement range.

  FIG. 14 is a flowchart illustrating a procedure of measurement range setting processing of the mobile terminal device 200 according to the modification. The measurement range setting process corresponds to step S406 in FIG.

  First, the reception control unit 234 receives the signal component in each axial direction detected by the antenna of each channel. For example, the reception control unit 234 acquires the value of the amplification factor of the VGA 217 for each of the three channels (ch1, ch2, ch3) as the optimum range information of each channel (step S4061).

  Next, the reception control unit 234 calculates an average value of the three acquired values, and determines whether the calculated average value is greater than a predetermined threshold value, whether the first measurement range is set, 2 Select whether to set the measurement range.

  For example, as a first measurement example, the reception control unit 234 calculates the average value of 18 dB, 18 dB, and 18 dB when the values of the amplification factors of the VGA 217 of the three channels are 18 dB. The result is in the second measurement range.

  As a second measurement example, when the amplification factor values of the respective VGA 217 are 36 dB, 30 dB, and 18 dB, the reception control unit 234 calculates the average value thereof as 30 dB, and the determination result is the second. Set to the measurement range.

  As a third measurement example, the reception control unit 234 calculates the average value of 36 dB, 36 dB, and 18 dB when the gain values of the respective VGAs 217 are 36 dB, 36 dB, and 18 dB. Set to the measurement range.

  In accordance with the above method, the reception control unit 234 calculates an amplification factor that can be commonly used for each of the three channels from the value of the amplification factor of the VGA 217 corresponding to the three channels. The reception control unit 234 sets the VGA 217 based on the selected optimum range information (step S4062).

  In the above processing, the case where the number of optimal range candidates is two is illustrated, but the number of optimal range candidates may be three or more.

  In the case of the second modified example, the configuration of the amplifying unit can be simplified by sharing the amplifying unit (for example, VGA 217) for receiving the received signal with a plurality of systems in each channel.

  According to the embodiment described above, the portable side control unit 230 is instructed by instructing the reception sensitivity characteristic of the portable side reception unit 210 based on the strength value of the authentication signal received by the portable side reception unit 210. A plurality of authentication signals received after the reception sensitivity characteristic of the portable receiver 210 is adjusted to the reception sensitivity characteristic are discriminated. For example, the mobile-side control unit 230 causes the mobile-side transmission unit 220 to transmit an answer signal including the determination results of a plurality of authentication signals. The in-vehicle side control unit 30 determines whether the portable terminal device is based on the answer signal received by the in-vehicle side reception unit 50 based on the determination results of the plurality of authentication signals included in the signal received by the in-vehicle side reception unit 50. By determining whether or not the received signal is a regular request signal, the mobile terminal device authentication system 1 can improve the security of authentication. In addition, the result of the determination whether the signal received by the mobile terminal device 200 is a regular request signal is the result of the determination whether the mobile-side receiving unit 210 is a communication that has received the regular request signal. Also good.

  The mobile side control unit 230 of the mobile terminal device authentication system 1 performs a plurality of authentications based on the reception sensitivity characteristics of the mobile side reception unit 210 adjusted based on the intensity value of the authentication signal received by the mobile side reception unit 210. The authentication signal may be received, a plurality of authentication signals may be determined based on the intensity value, and the answer signal may be transmitted to the mobile-side transmitting unit 220.

  The in-vehicle side control unit 30 compares the transmission time of the authentication signal with the determination result of the authentication signal, and based on the comparison result, the signal received by the mobile terminal device 200 is a normal request signal. You may make it determine whether it exists.

  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 30 receives the answer received by the vehicle-mounted side receiving unit 50 based on information including the number of times determined as the first signal and the number of times determined as the second signal based on the first threshold. The signal may be determined.

  The authentication signal includes a first signal and a second signal having a signal strength smaller than that of the first signal. The portable-side control unit 230 identifies a first threshold that can identify the first signal and the second signal, and a third signal that has a smaller signal strength than the second signal. Information based on two threshold values and including the number of times determined as the first signal, the number of times determined as the second signal, and the number of times determined as the third signal. Information indicating the discrimination result of the signal. The portable side control unit 230 causes the portable side transmission unit to transmit the answer signal, and the in-vehicle side control unit determines the number of times determined as the first signal, the number of times determined as the second signal, and the third number. The answer signal received by the in-vehicle side receiving unit may be determined based on information including the number of times of the determination and the number of times determined.

  The in-vehicle side control unit determines that the signal received by the in-vehicle side receiving unit is not in an appropriate state with respect to the reception sensitivity characteristic of the portable side receiving unit when there is no turn determined as the second signal. However, if there is a time when the signal is determined to be the second signal, it is determined that the signal received by the in-vehicle side reception unit is in an appropriate state with respect to the reception sensitivity characteristic of the portable side reception unit. May be.

  According to this configuration, the mobile terminal device authentication system determines that the signal is the second signal, so that the signal received by the in-vehicle side receiving unit is in an appropriate state with respect to the reception sensitivity characteristic of the mobile side receiving unit. And the determination accuracy at the time of authentication can be further improved.

  Whether the in-vehicle side control unit is a request signal transmitted by the in-vehicle side transmission unit based on a determination result of the plurality of authentication signals included in the answer signal. It may be determined whether or not.

  The vehicle-mounted side control unit is the answer signal transmitted by the mobile-side transmitting unit based on the determination result of the plurality of authentication signals included in the answer signal. It may be determined whether or not.

  The in-vehicle side control unit may cause the in-vehicle side transmission unit to transmit the authentication signal having a transmission time irregularly determined from predetermined patterns.

According to the mobile terminal device authentication system 1 in the embodiment, the signal strength of the request signal is easily changed 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. be able to.
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 an irregularly determined transmission time. Thus, 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 addition, the mobile terminal device authentication system 1 in the above-described embodiment determines whether the signal received by the mobile terminal device 200 is a legitimate request signal, based on the mobile terminal device 200 side, that is, the mobile side control unit 230. May be implemented. For example, the mobile-side control unit 230 can obtain the determination result on the mobile terminal device 200 side by performing the determination process described above as the process of the in-vehicle side control unit 30. In the above case, the mobile-side control unit 230 includes the result of the above determination in the answer signal, transmits it to the in-vehicle device 100, displays it on the display unit included in the mobile terminal device 200, or displays the in-vehicle device 100. Control may be made so that an external device other than the above is notified and output.

  In the mobile terminal device authentication system 1 according to the above-described embodiment, the signal strength (output) at the time of sending (transmitting) the authentication information included in the request signal varies depending on the resonance characteristic of the resonance unit 43 and the difference in frequency. However, the present invention is not limited to this. For example, the signal strength (or gain) for each piece of authentication information may be made different by a filter circuit or the like in which the resonance characteristics of the resonance unit 43 are simulated. The filter circuit may be realized by an analog circuit, a digital circuit, or a combination of these circuits. For example, the in-vehicle control unit 30 generates a periodic signal in which a sine wave or a harmonic component is suppressed. And you may supply to the drive part 41. FIG.

  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... Mobile side control unit, 231... Signal strength measuring unit, 232... Reception time measuring unit, 233... Signal generation unit, 234 .. reception control unit, V .. scooter, E. Tteri, H ... handle

Claims (12)

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 an answer signal received by the in-vehicle side reception unit;
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 vehicle-mounted side control unit
As the request signal, a signal including a plurality of authentication signals set to have different received signal strengths is transmitted to the in-vehicle side transmission unit,
The mobile-side receiver is
The reception sensitivity characteristic can be adjusted by control, and the signal transmitted by the vehicle-mounted side transmission unit is received as the request signal.
The portable side control unit is
Based on the strength value of the authentication signal received by the portable-side receiver, the reception sensitivity characteristic of the portable-side receiver is instructed, and the reception sensitivity characteristic of the portable-side receiver is adjusted to the instructed reception sensitivity characteristic The plurality of authentication signals received after being received,
The in-vehicle side control unit or the portable side control unit is
It is determined whether or not the mobile-side receiving unit is a communication that has received a normal request signal based on the determination results of the plurality of authentication signals.
Mobile terminal device authentication system. The portable side control unit is
Based on the strength value of the authentication signal received by the portable-side receiver, the reception sensitivity characteristic of the portable-side receiver is instructed, and the reception sensitivity characteristic of the portable-side receiver is adjusted to the instructed reception sensitivity characteristic Discriminating the plurality of authentication signals received after being sent, and causing the portable-side transmission unit to transmit an answer signal including the discrimination results of the plurality of authentication signals.
The mobile terminal device authentication system according to claim 1. The portable side control unit is
Based on the intensity value, the plurality of authentication signals are received based on the reception sensitivity characteristic of the portable side receiver adjusted based on the strength value of the authentication signal received by the portable side receiver. Determining the plurality of authentication signals, and transmitting the answer signal to the mobile-side transmitter.
The mobile terminal device authentication system according to claim 1 or 2. The in-vehicle side control unit compares the transmission time of the authentication signal with the determination result of the authentication signal, and based on the comparison result, the signal received by the mobile terminal device is a normal request signal. Determine if there is,
The portable terminal device authentication system according to any one of claims 1 to 3. 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
Determining an answer signal received by the in-vehicle-side receiving unit based on information including the number of times determined as the first signal and the number of times determined as the second signal based on a first threshold;
The portable terminal device authentication system according to any one of claims 1 to 3. The authentication signal includes a first signal and a second signal having a signal strength smaller than that of the first signal,
The portable side control unit is
Discrimination based on a first threshold capable of distinguishing the first signal and the second signal and a second threshold identifying a third signal having a signal strength smaller than that of the second signal The information including the number of times determined as the first signal, the number determined as the second signal, and the number determined as the third signal indicates the determination result of the plurality of authentication signals. Information, let the portable side transmission unit transmit the answer signal,
The vehicle-mounted side control unit is configured by the vehicle-mounted side receiving unit based on information including the number of times determined as the first signal, the number of times determined as the second signal, and the number of times determined as the third signal. Determine the received answer signal;
The portable terminal device authentication system according to any one of claims 1 to 3. The vehicle-mounted side control unit
If there is no time determined to be the second signal, it is determined that the signal received by the in-vehicle side reception unit is not in an appropriate state with respect to the reception sensitivity characteristic of the portable side reception unit,
When there is a time determined to be the second signal, it is determined that the signal received by the in-vehicle side receiving unit is in an appropriate state with respect to the reception sensitivity characteristic of the portable side receiving unit,
The mobile terminal device authentication system according to claim 5 or 6. The vehicle-mounted side control unit
Based on the determination result of the plurality of authentication signals included in the answer signal, it is determined whether or not the signal received by the mobile-side receiver is a request signal transmitted by the in-vehicle side transmitter. ,
The mobile terminal device authentication system according to any one of claims 1 to 7. The vehicle-mounted side control unit
Based on the determination result of the plurality of authentication signals included in the answer signal, it is determined whether or not the signal received by the in-vehicle side receiving unit is the answer signal transmitted by the portable side transmitting unit. To
The portable terminal device authentication system according to any one of claims 1 to 8. The in-vehicle side control unit causes the in-vehicle side transmission unit to transmit the authentication signal having a transmission time irregularly determined from predetermined patterns.
The portable terminal device authentication system according to any one of claims 1 to 9. An in-vehicle transmission unit that transmits a request signal to the mobile terminal device;
A vehicle-side receiving unit for receiving signals;
An in-vehicle side control unit for transmitting a request signal to the in-vehicle side transmission unit and determining an answer signal received by the mobile terminal device;
With
The vehicle-mounted side control unit
As the request signal, a signal including a plurality of authentication signals set to have different received signal strengths is transmitted to the in-vehicle side transmission unit,
The in-vehicle side receiving unit is
The mobile terminal device received after the reception sensitivity characteristic of the mobile terminal device is adjusted based on the strength value of the authentication signal received by the mobile terminal device, and the reception sensitivity characteristic of the mobile terminal device is adjusted Receiving a signal including the result of the determination of a plurality of authentication signals,
The vehicle-mounted side control unit
Based on the determination result of the plurality of authentication signals included in the signal received by the in-vehicle side receiving unit, the signal received by the mobile terminal device from the answer signal received by the in-vehicle side receiving unit is legitimate. Determine whether it is a request signal,
In-vehicle device. A mobile-side receiver that receives a request signal from the in-vehicle device;
A portable transmitter that transmits a signal;
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 mobile-side receiver is
It is possible to adjust the reception sensitivity characteristic by control, receive the request signal transmitted by the in-vehicle device,
The portable side control unit is
Based on the strength value of the authentication signal received by the portable-side receiver, the reception sensitivity characteristic of the portable-side receiver is instructed, and the reception sensitivity characteristic of the portable-side receiver is adjusted to the instructed reception sensitivity characteristic Discriminating a plurality of authentication signals received after
Mobile terminal device.

Images