JP2009127345A - Smart entry system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a smart entry system which can dispense with installation of an LF antenna to reduce system cost. <P>SOLUTION: The smart entry system comprises a modulation output part 12 which outputs first information to be sent to a portable key 2 as a modulating signal modulated to a predetermined frequency, an electrode 15 which is installed in an outer door handle 14 which a driver 1 touches, and wiring 18 which connects between the modulation output part 12 and the electrode 15 to energize the modulating signal to the electrode 15. When the driver 1 touches the electrode 15, an authentication ECU 11 energizes the modulating signal from the modulation output part 12 to the driver 1 through the wiring 18 and the electrode 15. Electric waves are sent from the driver 1 himself by the energizing, and the first information is sent to the portable key 2 which the driver has by the electric waves. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a smart entry system.

  The smart entry system is a system that can lock / unlock the door and start the engine by authenticating the mobile key by two-way communication between the vehicle and the mobile key by simply holding the mobile key. .

JP 2006-009312 A

  In the case of two-way communication using radio waves, the radio wave generated from the vehicle needs to have an electric field intensity that can be received only within a limited range (for example, in the passenger compartment or around the door), so the frequency used is the LF band (125 KHz). (Near) is the main. Therefore, an outdoor detection LF antenna for detecting the presence of the portable key outside the vehicle room around the door when the door is accessed, and an indoor detection LF antenna for detecting the presence of the portable key in the vehicle interior when the engine is started. Etc., and a large number of LF antennas are arranged in the vehicle to establish the system.

  As described above, in order to detect the location where the portable key is present by radio waves and confirm where the driver holding the portable key is, it has conventionally been necessary to install a large number of LF antennas at various locations in the vehicle. It was. For example, in a general vehicle, outdoor detection LF antennas are installed on the driver side door, passenger side door, and tail gate, and the indoor detection LF antennas are installed on the front side of the room, the center of the room, and the rear side of the room. 6 LF antennas were required. However, in such a configuration, the number of LF antennas to be installed is not small, and the installation cost is high, and the cost for arranging the harness for the LF antenna is also high, which increases the system cost.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a smart entry system that does not require installation of an LF antenna and can reduce system cost.

The smart entry system according to the first invention for solving the above-mentioned problems is
When communication is performed between the portable device possessed by the driver and the authentication control device provided in the vehicle, and it is authenticated that the portable device is previously registered in the authentication control device, a predetermined authentication is performed. In the smart entry system that operates,
Modulation output means for outputting first information to be transmitted to the portable device as a modulated signal modulated to a predetermined frequency;
Electrodes provided around or inside the vehicle touched by the driver;
A wiring for connecting the modulation output means and the electrode and energizing the modulation signal to the electrode;
When the driver touches the electrode, the authentication control device energizes the driver with the modulation signal from the modulation output means via the wiring and the electrode, and from the human body surface of the driver by the energization A radio wave is transmitted, and the first information is transmitted to the portable device possessed by the driver by the radio wave.

A smart entry system according to a second invention for solving the above-mentioned problem is as follows.
In the smart entry system according to the first invention,
Contact detecting means for detecting that the driver touches the electrode;
The authentication control device outputs the modulation signal from the modulation output unit when the contact detection unit detects that the driver touches the electrode.

A smart entry system according to a third invention for solving the above-mentioned problem is as follows.
In the smart entry system according to the first or second invention,
Including receiving means for receiving UHF radio waves, and providing the electrodes on the handle of the vehicle door;
The authentication control device outputs the modulation signal from the modulation output means when the driver touches or detects that the electrode provided on the handle is touched,
When the first information is received by the portable device and the second information is transmitted from the portable device by UHF radio waves, the received UHF radio waves are received by the receiving means, and the second information Information is authenticated, and when the portable device is authenticated as being registered in advance, the door is unlocked or locked.

A smart entry system according to a fourth invention for solving the above-mentioned problem is as follows.
In the smart entry system according to the first or second invention,
Including a receiving means for receiving UHF radio waves, and providing the electrode to a start switch of the vehicle engine;
The authentication control device outputs the modulation signal from the modulation output means when the driver touches or detects that the electrode provided on the start switch is touched,
When the first information is received by the portable device and the second information is transmitted from the portable device by UHF radio waves, the received UHF radio waves are received by the receiving means, and the second information Information is authenticated, and when it is authenticated that the portable device is registered in advance, the engine is permitted to start.

A smart entry system according to a fifth invention for solving the above-mentioned problem is as follows.
In the smart entry system according to any one of the first to fourth inventions,
The predetermined frequency in the modulated signal is a high frequency band, preferably a UHF band.

  According to the first invention, since the human body itself can function as an antenna by using a modulation signal modulated to a predetermined frequency, the radio wave is transmitted from the driver (human body) itself touching the electrode, Information can be transmitted to the portable device possessed by the driver by radio waves. As a result, installation of LF antennas, which has conventionally been necessary in large numbers, is unnecessary, and the system cost can be reduced.

  According to the second invention, the modulation signal can be output only when the driver touches the electrode.

  According to the third aspect of the invention, the modulation signal can be output only when the driver touches the electrode provided on the handle of the door, and the door can be locked or unlocked without fail.

  According to the fourth aspect of the invention, the modulation signal can be output only when the driver touches the electrode provided on the engine start switch, and the engine can be permitted to start reliably.

  According to the fifth aspect of the invention, since the modulation signal is modulated to a high frequency band, preferably the UHF band, the human body itself can function reliably as an antenna, and the distance of radio waves from the human body can be set within a desired range. It can be.

  Hereinafter, a smart entry system according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram illustrating a smart entry system according to the present invention. 2 and 3 are flowcharts for explaining authentication control in the smart entry system according to the present invention.

  The smart entry system of this embodiment performs two-way communication between a portable key 2 that is a portable device possessed by a driver 1 and an authentication ECU (Electronics Control Unit) 11 that is an authentication control device provided in the vehicle. When it is authenticated that the portable key 2 is previously registered in the authentication ECU 11, a predetermined authentication operation is performed.

  Although not shown, the portable key 2 is registered in advance in the authentication ECU 11 when receiving the key verification information and the receiving unit that receives the key verification information (first information) transmitted from the authentication ECU 11 side. A transmitting unit that performs cryptographic calculation including the registered information and transmits the calculated cryptographic calculation information (second information) using radio waves in the UHF band (for example, 300 MHz to 400 MHz). More specifically, the receiving unit of the portable key 2 can wirelessly receive a modulation signal of key collation information modulated by a modulation output unit 12 (modulation output unit) described later.

  The authentication ECU 11 receives the key output information transmitted to the portable key 2 as a modulated signal modulated to a predetermined frequency, and the cryptographic operation information transmitted from the portable key 2 as a UHF band radio wave. It has a UHF receiver 13 (receiving means). In this embodiment, the authentication ECU 11 includes a modulation output unit 12 and a UHF receiver 13 inside. However, the modulation output unit 12 and the UHF receiver 13 are separate from the authentication ECU 11. It may be provided independently.

  Further, an outer door handle 14 and an ignition knob 16 which are places around or inside the vehicle touched by the driver 1 are provided with an outer door handle electrode (hereinafter abbreviated as a handle electrode) 15, an ignition knob electrode (hereinafter referred to as a knob electrode). Abbreviated.) 17 is provided. The handle electrode 15 and the knob electrode 17 are connected to the modulation output unit 12 by wiring 18. Therefore, when the driver 1 touches the handle electrode 15 or the knob electrode 17, the authentication ECU 11 energizes the driver 1 with the modulation signal output from the modulation output unit 12 via the wiring 18, the handle electrode 15 or the knob electrode 17. is doing.

  The outer handle 14 is provided with a touch sensor 19 (contact detection means) that detects that the driver 1 has touched the handle electrode 15. Further, the ignition knob 16 is provided with a knob switch 20 for detecting that the ignition knob 16 is pushed (or turned), and the driver 1 is attached to the knob electrode 17 according to the operation state of the knob switch 20. Touching is indirectly detected to function as contact detection means. Therefore, in the authentication ECU 11, when the tentacles of the driver 1 to the handle electrode 15 and the knob electrode 17 are detected by the touch sensor 19 and the knob switch 20, the key verification information output to the handle electrode 15 and the knob electrode 17 is displayed. Modulation is performed by the modulation output unit 12, and a modulated signal (key verification information) after modulation is output to the handle electrode 15 and the knob electrode 17 via the wiring 18.

  Here, the frequency of the modulation signal (key collation information) energized from the modulation output unit 12 to the handle electrode 15 and the knob electrode 17 will be described. The modulation signal is modulated to a high frequency band that can be transmitted from the human body as radio waves in the air, preferably to a frequency in the UHF band. This is because the human body has moisture as a main component, and for a frequency in a high frequency band, there is a physical phenomenon that the radio wave propagation in the human body can be approximated to the situation of radio wave propagation by a metal conductor. Therefore, in the present invention, by utilizing such a physical phenomenon, the human body is positioned as an antenna in radio wave communication, and a modulation signal (key verification information) is energized from the modulation output unit 12 to the driver 1, whereby the human body surface of the driver 1 A radio signal is transmitted from the mobile phone 2 and a modulation signal (key verification information) is transmitted by radio to the portable key 2 possessed by the driver 1.

  At this time, a weak radio wave is transmitted so that the modulated signal (key collation information) can be received only when the driver 1 has the portable key 2. For example, the flight distance of radio waves transmitted from the human body surface is set to about 50 cm around the human body as much as possible. As a result, the modulation signal (key verification information) can be received by the portable key 2 only when the driver 1 is in contact with the handle electrode 15 and the knob electrode 17 and the driver 1 has the portable key 2. In addition, when the driver 1 has the portable key 2, specifically, when the portable key 2 is held in the hand of the driver 1, and the portable key 2 is in the pocket of the driver 1. This is the case when the portable key 2 is in the bag (except for the metal bag) held by the driver 1.

  Although it is desirable that the skin of the driver 1 is in direct contact with the handle electrode 15 and the knob electrode 17, the handle electrode 15 and the knob electrode 17 should The bare skin may not be directly touched. Therefore, the frequency band of the modulation signal (key verification information) is set so that the modulation signal (key verification information) can be energized to the driver 1 side even if the handle electrode 15 and knob electrode 17 are not directly touched. May be.

  Next, with reference to the block diagram of FIG. 1, authentication control by bidirectional communication between the portable key 2 and the authentication ECU 11 will be specifically described based on the flowchart of FIG. 2 or FIG. 3.

<Door access>
The case of performing door access authentication control (door unlocking or locking operation) in the smart entry system of the present embodiment will be described with reference to the block diagram of FIG. 1 and the flowchart of FIG.

(Step S1)
It is confirmed whether or not the outer door handle 14 (handle electrode 15) has a tentacle of the driver 1. Only when there is a tentacle, the process proceeds to step S2. At this time, the presence or absence of a tentacle is detected by touching the handle electrode 15 by a touch sensor 19 (for example, a capacitive touch sensor) built in the outer door handle 14. Note that a push button or the like may be used instead of the touch sensor 19.

(Step S2)
When the tentacles of the driver 1 to the outer door handle 14 (handle electrode 15) are detected, the modulation output unit 12 of the authentication ECU 11 generates the key collation information as a modulation signal modulated to a predetermined frequency, and at the predetermined frequency. The modulated key collation information (modulation signal) is output from the modulation output unit 12 of the authentication ECU 11 to the handle electrode 15 by wire via the wiring 18.

(Steps S3 and S4)
The key verification information (modulated signal) modulated to a predetermined frequency is energized to the surface of the body through a part of the body of the driver 1 touching the handle electrode 15. Since the driver 1 itself becomes a human body pseudo antenna for a predetermined frequency, the key verification information (modulated signal) modulated to the predetermined frequency is transmitted as a radio wave from the surface of the driver 1 body. In this way, the key verification information is wirelessly transmitted to the portable key 2 possessed by the driver 1 by the radio wave transmitted from the body surface of the driver 1. That is, the modulation signal is energized only to the driver 1 who touches the handle electrode 15 and possesses the portable key 2, and as a result, the portable key possessed by the driver 1 from the vehicle side (authentication ECU 11). The key verification information is transmitted to 2.

(Step S5)
When the portable key 2 is located around the body of the driver 1, that is, when the driver 1 has the portable key 2, the portable key 2 receives key verification information (modulated signal) modulated to a predetermined frequency. The process proceeds to step S6. On the other hand, if there is no portable key 2 around the driver 1, the portable key 2 cannot receive key verification information (modulated signal) modulated to a predetermined frequency, and the process returns to step S1. . When returning to step S1, for example, when a time-out period is provided for the UHF radio wave transmitted from the mobile key 2, and no UHF radio wave is transmitted from the mobile key 2 even if the time-out period is exceeded, Return to step S1.

(Step S6)
When the portable key 2 is present around the body of the driver 1, a modulation signal (key verification information) transmitted from the surface of the driver 1 body is received by the portable key 2. The portable key 2 performs cryptographic calculation including registration information registered in the authentication ECU 11 in advance, and wirelessly transmits the cryptographic calculation information as a result of the calculation using radio waves in the UHF band. As a result, the driver 1 The UHF radio wave (cryptographic calculation information) is transmitted from the portable key 2 possessed by the vehicle to the vehicle side (authentication ECU 11).

(Step S7)
On the vehicle side (authentication ECU 11), the UHF radio wave (cryptographic calculation information) transmitted from the portable key 2 is received by the UHF receiver 13 of the authentication ECU 11.

(Step S8)
At this time, it is confirmed whether or not the UHF radio wave (cryptographic calculation information) received by the UHF receiver 13 matches the result calculated in advance by the authentication ECU 11. If it is confirmed, the process proceeds to step S9. If it cannot be confirmed, the process returns to step S1.

(Step S9)
If the results match, the portable key 2 has been authenticated. Then, a control signal is transmitted from the authentication ECU 11 to the body control ECU 21, and a drive request is output to the door lock actuator 23 via the body control ECU 21. At this time, the body control ECU 21 and the door lock actuator 23 perform locking / unlocking according to the situation. The above steps S7 to S9 have the same logic as that of the conventional smart entry system.

<Engine start>
In the smart entry system of the present embodiment, the case of performing engine start authentication control (engine start permission) will be described with reference to the block diagram of FIG. 1 and the flowchart of FIG.

(Step S11)
It is confirmed whether or not the ignition knob 16 that is a knob type engine start switch has been pressed, in other words, whether or not the knob electrode 17 has the tentacles of the driver 1. Only when it is pressed, the process proceeds to step S12. Here, the tentacles to the knob electrode 17 are confirmed by detecting whether or not the ignition knob 16 is pressed. However, in the case of a push type engine start switch, whether or not the push switch is pressed is detected. Check the tentacles to the electrode.

(Step S12)
When the ignition knob 16 is pressed (when the tentacle of the driver 1 to the knob electrode 17 is detected), the modulation output unit 12 of the authentication ECU 11 generates key verification information as a modulation signal modulated to a predetermined frequency, and The key verification information (modulated signal) modulated to a predetermined frequency is output from the modulation output unit 12 of the authentication ECU 11 to the knob electrode 17 via the wiring 18 by wire.

(Steps S13 and S14)
The key verification information (modulated signal) modulated to a predetermined frequency is energized to the surface of the body through a part of the body of the driver 1 touching the knob electrode 17. Since the driver 1 itself becomes a human body pseudo antenna for a predetermined frequency, the key verification information (modulated signal) modulated to the predetermined frequency is transmitted as a radio wave from the surface of the driver 1 body. In this way, the key verification information is wirelessly transmitted to the portable key 2 possessed by the driver 1 by the radio wave transmitted from the body surface of the driver 1. That is, the modulation signal is energized only to the driver 1 who touches the knob electrode 17 and has the portable key 2, and as a result, the portable key possessed by the driver 1 from the vehicle side (authentication ECU 11). The key verification information is transmitted to 2.

(Step S15)
When the portable key 2 is located around the body of the driver 1, that is, when the driver 1 has the portable key 2, the portable key 2 receives key verification information (modulated signal) modulated to a predetermined frequency. The process proceeds to step S16. On the other hand, when there is no portable key 2 around the body of the driver 1, the portable key 2 cannot receive key verification information (modulated signal) modulated at a predetermined frequency, and the process returns to step S11. . When returning to step S11, for example, a timeout time is provided for the UHF radio wave transmitted from the portable key 2, and when the UHF radio wave is not transmitted from the portable key 2 even if the timeout time is exceeded, Return to step S11.

(Step S16)
When the portable key 2 is present around the body of the driver 1, a modulation signal (key verification information) transmitted from the surface of the driver 1 body is received by the portable key 2. The portable key 2 performs cryptographic calculation including registration information registered in the authentication ECU 11 in advance, and wirelessly transmits the cryptographic calculation information as a result of the calculation using radio waves in the UHF band. As a result, the driver 1 The UHF radio wave (cryptographic calculation information) is transmitted from the portable key 2 possessed by the vehicle to the vehicle side (authentication ECU 11).

(Step S17)
On the vehicle side (authentication ECU 11), the UHF radio wave (cryptographic calculation information) transmitted from the portable key 2 is received by the UHF receiver 13 of the authentication ECU 11.

(Step S18)
At this time, it is confirmed whether or not the UHF radio wave (cryptographic calculation information) received by the UHF receiver 13 matches the result calculated in advance by the authentication ECU 11. If it is confirmed, the process proceeds to step S19. If it cannot be confirmed, the process returns to step S11.

(Step S19)
If the results match, the portable key 2 has been authenticated. Then, the authentication ECU 11 unlocks the handle lock and transmits an engine start permission control signal from the authentication ECU 11 to the engine ECU 22 so that the engine can be started. The above steps S17 to S19 have the same logic as that of the conventional smart entry system.

  As described above, in the smart entry system according to the present invention, it is assumed that the driver 1 who operates the vehicle always has the portable key 2 and uses the driver 1 itself as one of the communication paths. Only the vicinity of the driver 1 carrying the portable key 2 is within a range in which communication radio waves from the vehicle side can be received, and the location of the portable key 2 is easily and reliably identified, and authentication by two-way communication is performed. Implementation is possible. As a result, it is no longer necessary to install a large number of LF antennas required in the conventional smart entry system in the vehicle, and a harness for a large number of LF antennas is also unnecessary, which can greatly reduce the system cost. became.

  In addition, in the portable key used in the conventional smart entry system, the degree of change of the system can be reduced as much as possible by changing only the receiving unit so that a predetermined frequency can be received. As a result, the system cost can be suppressed even when the conventional system is changed.

  The smart entry system according to the present invention is suitable for application to a vehicle or the like.

It is a block diagram explaining the smart entry system concerning the present invention. It is a flowchart which shows the procedure in the case of performing the authentication control of door access in the smart entry system which concerns on this invention. It is a flowchart which shows the procedure in the case of performing engine start authentication control in the smart entry system which concerns on this invention.

Explanation of symbols

1 Driver 2 Mobile key 11 Authentication ECU
12 Modulation Output Unit 13 UHF Receiver 14 Outer Door Handle 15 Outer Door Handle Electrode 16 Ignition Knob 17 Ignition Knob Electrode 18 Wiring 19 Touch Sensor 20 Knob Switch 21 Body Control ECU
22 Engine ECU
23 Door lock actuator

Claims (5)

When communication is performed between the portable device possessed by the driver and the authentication control device provided in the vehicle, and it is authenticated that the portable device is previously registered in the authentication control device, a predetermined authentication is performed. In the smart entry system that operates,
Modulation output means for outputting first information to be transmitted to the portable device as a modulated signal modulated to a predetermined frequency;
Electrodes provided around or inside the vehicle touched by the driver;
A wiring for connecting the modulation output means and the electrode and energizing the modulation signal to the electrode;
When the driver touches the electrode, the authentication control device energizes the driver with the modulation signal from the modulation output means via the wiring and the electrode, and from the human body surface of the driver by the energization A smart entry system that transmits radio waves and transmits the first information to the portable device possessed by the driver by the radio waves. The smart entry system according to claim 1,
Contact detecting means for detecting that the driver touches the electrode;
The authentication control device outputs the modulation signal from the modulation output unit when the contact detection unit detects that the driver touches the electrode. In the smart entry system according to claim 1 or claim 2,
Including receiving means for receiving UHF radio waves, and providing the electrodes on the handle of the vehicle door;
The authentication control device outputs the modulation signal from the modulation output means when the driver touches or detects that the electrode provided on the handle is touched,
When the first information is received by the portable device and the second information is transmitted from the portable device by UHF radio waves, the received UHF radio waves are received by the receiving means, and the second information A smart entry system that performs authentication of information and performs an unlocking or locking operation of a corresponding door when the portable device is authenticated as being registered in advance. In the smart entry system according to claim 1 or claim 2,
Including a receiving means for receiving UHF radio waves, and providing the electrode to a start switch of the vehicle engine;
The authentication control device outputs the modulation signal from the modulation output means when the driver touches or detects that the electrode provided on the start switch is touched,
When the first information is received by the portable device and the second information is transmitted from the portable device by UHF radio waves, the received UHF radio waves are received by the receiving means, and the second information A smart entry system that authenticates information and permits engine start when the portable device is authenticated as being registered in advance. In the smart entry system according to any one of claims 1 to 4,
A smart entry system, wherein a predetermined frequency in the modulation signal is a high frequency band, preferably a UHF band.

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