JP2009287202A - Electronic key device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic key device enabling an authentication time to be shortened, enabling the power consumption of an on-vehicle device to be suppressed, and increased in responsiveness. <P>SOLUTION: The on-vehicle device 10 includes a transmission/receiving means 12 for receiving a signal transmitted from a receiving antenna 21 through an LPF changing means 24, a CPU 13, and a memory 15, and operates a control device 30 through the communication with a plurality of mobile devices 40A, 40B. Also, the on-vehicle device transmits the signals of the plurality of mobile devices 40A, 40B simultaneously, and changes the LPF of a receiver 20 in such a manner that the signal transmitted simultaneously can be identified so that the signal can be received normally even if the transmission timing thereof is slightly deviated. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electronic key device that collates an ID code and performs door / handle lock, trunk locking / unlocking, engine starting, and the like by, for example, communication between a portable device for a vehicle and a vehicle-mounted device.

  Conventionally, when performing door locking / unlocking of a vehicle and starting an engine, a user inserts a key into a keyhole and rotates it, or a so-called FOB key, in a user's pocket or bag, Wireless communication was performed between the vehicle-mounted device and the key (portable device) without touching the key at all, and the ID code from the portable device was checked against the code stored in the vehicle-mounted device. There is an electronic key device for a vehicle in which the vehicle-mounted device can unlock or lock the door simply by touching the sensor.

  Further, in the vehicle electronic key device as described above, a request for performing verification from the vehicle-mounted device is periodically transmitted by transmitting a radio signal, and a portable device registered in an unlockable area of the vehicle approaches. And the in-vehicle device verifies the signal responded from the portable device (see, for example, Patent Document 1).

JP 2007-63800 A

  In the conventional vehicle electronic key device as described above, the communication signal is transmitted with a predetermined time difference for each portable device for the purpose of shortening the authentication time in communication between the portable device and the controlled device. Replies were made without overlapping. For this reason, even if there are no portable devices in the detection area, it is necessary to wait for the number of registrations, and there is a problem that authentication time becomes long and door lock / unlock is delayed.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an electronic key that can shorten the authentication time, suppress power consumption of the vehicle-mounted device, and improve responsiveness. Get the device.

  When the electronic key device according to the present invention authenticates the ID code of the portable device by communicating between the mounted device mounted on the vehicle and the portable device existing in a specific area of the vehicle. In the electronic key device for operating the control device mounted on the vehicle, the first low-pass filter mounted on the vehicle and having a cut-off frequency capable of receiving high frequencies, and the second having a cut-off frequency capable of receiving low frequencies A low-pass filter, a receiver including LPF changing means for switching between the first low-pass filter and the second low-pass filter, and periodically transmitting a request signal, and then controlling the LPF changing means of the receiver. When the request signal is received and the on-board device that switches the filter of the receiver to the second low-pass filter side, the same answer signal is simultaneously transmitted. And a plurality of mobile devices that signal provided, the mounting unit, through the second low-pass filter of the receiver, and receives the answer signal at the same time.

  Since the electronic key device according to the present invention determines the answer signal that has responded simultaneously from a plurality of registered portable devices, the time is constant regardless of the number of registrations when there is no portable device. Since there is no need to wait for the time, the authentication time can be shortened, and the effects of suppressing the power consumption of the vehicle-mounted device and improving the responsiveness are achieved.

  Further, even when the answer that has been simultaneously responded cannot be normally received or when the answer signal cannot be normally received due to transient noise, the second request signal can be transmitted by determining the similarity of the answer signals. Therefore, non-detection can be prevented.

Embodiment 1 FIG.
An electronic key device according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 is a diagram showing a configuration of an electronic key device according to Embodiment 1 of the present invention.

  In FIG. 1, an electronic key device according to Embodiment 1 of the present invention is mounted on a vehicle-mounted device (mounting device) 10 disposed at a predetermined location of a vehicle and mounted at a predetermined location on the vehicle, and is transmitted simultaneously or individually. A receiver 20, a portable device 40A, and a portable device 40B that change the LPF according to the above are provided.

  The vehicle-mounted device 10 is provided with a transmission antenna 11, a transmission / reception unit 12, a CPU 13, an answer signal similarity determination unit 14, a memory 15, and a driving unit 16.

  The receiver 20 is provided with a receiving antenna 21, a filter circuit connected between the receiving antenna 21 and the transmitting / receiving means 12, and an LPF changing means (switch) 24 for switching the filter circuit. The filter circuit includes a low-pass filter (LPF1) 22 having a cutoff frequency at which high frequencies can be received, and a low-pass filter (LPF2) 23 having a cutoff frequency at which low frequencies can be received. The LPF changing means (switch) 24 switches between the low pass filter 22 and the low pass filter 23.

  The portable device 40A is provided with a transmission / reception means 41 including a transmission / reception antenna, a CPU 42, a memory 43, and a battery 44. The same applies to the portable device 40B.

  In addition to this, FIG. 1 shows, for example, a vehicle control device 30 such as a door locking / unlocking device and an engine start device, and a switch 31 provided in the vehicle.

  The memory 15 of the in-vehicle device 10 includes the first request signal in which a part of the ID of the registered in-vehicle device 10 is included and the first ID in which the registered ID of the in-vehicle device 10 is all included. 2 request signals, a third request signal in which the portable device number is inherent, a first answer signal, a second answer signal, a third answer signal including the IDs of the portable devices 40A and 40B, etc. Is registered in advance. The priority order is determined in the registration order of the portable devices 40A and 40B.

  In each of the memories 43 of the portable devices 40A and 40B, the first answer signal, the second answer signal, the third answer signal including the unique ID of the portable device, and the ID of the portable device are registered. The ID of the vehicle-mounted device, the portable device number, and the like are registered in advance.

  Next, the operation of the electronic key device according to the first embodiment will be described with reference to the drawings.

  FIG. 2 is a timing chart showing the operation of the electronic key device according to Embodiment 1 of the present invention. FIG. 3 is a flowchart showing the operation of the vehicle-mounted device of the electronic key device according to Embodiment 1 of the present invention.

  The basic operation of the vehicle-mounted device 10 is as follows. First, the CPU 13 and the transmission / reception means 12 operate, and the first request signal read from the memory 15 is periodically transmitted from the transmission antenna 11. A first request signal for determining whether there is a registered portable device is transmitted to the portable devices 40A and 40B of the user. In response to this, the portable devices 40A and 40B transmit the first answer signal.

  The vehicle-mounted device 10 receives this via the antenna 21, the LPF changing unit 24, and the transmitting / receiving unit 12. The CPU 13 decodes the received content, reads the first answer stored in the memory 15 and collates it. When the first answer signal stored in the memory 15 matches the received first answer signal, a second request signal for detecting the registered portable device number is sent to the portable devices 40A and 40B of the user. Send to. In response to this, the portable devices 40A and 40B transmit a second answer signal corresponding to the registered portable device number.

  The CPU 13 of the vehicle-mounted device 10 collates the received second answer signal with the second answer read from the memory 15 and stored in the memory 15. When the verification matches, the on-vehicle device 10 decodes the registered mobile device number from the time from the end of the second request signal transmission to the completion of the second answer signal reception, and detects the mobile device detected by the second answer signal. A third request signal for authenticating whether the portable device is registered to the device is transmitted. The portable device requested for the third request signal transmits a third answer signal including the ID information read from the memory 43.

  The CPU 13 of the vehicle-mounted device 10 decodes the received third answer signal, reads the third answer signal including IDA and IDB stored in the memory 15 and collates it. When the ID stored in the memory 15 matches the received content, so-called authentication is completed, and the CPU 13 outputs a control signal via the driving means 16. As a result, the control device 30 operates so as to unlock the door or allow the engine to start, for example, by an input of a switch 31 provided in the vehicle.

  On the other hand, since the portable devices 40A and 40B have the same configuration, the portable device 40A will be described. The basic operation of the portable device 40A is as follows. The transmission / reception means 41 receives the first request signal, the second request signal, and the third request signal transmitted from the vehicle-mounted device 10, and the CPU 42 first determines from the contents whether or not a request has been made to itself. .

  A part of the ID of the registered in-vehicle device 10 is inherent in the first request signal, the ID of the registered in-vehicle device 10 is included in the second request signal, and the portable ID is included in the third request signal. Since the device number is inherent, no answer signal is transmitted in the case of the ID or portable device number of the vehicle-mounted device 10 that is not registered in the memory 43. When the request signal is for the portable device 40 </ b> A, the CPU 42 reads out the third answer signal stored in the memory 43, encrypts it, and transmits it from the transmission / reception means 41.

  Here, since it is unclear which portable device the user is using, the vehicle-mounted device 10 is a portable device registered in a specific area of the vehicle (for example, an area near the door when the door is unlocked). A request signal is transmitted periodically. In order to improve the responsiveness (for example, the responsiveness of unlocking the door), it is necessary to periodically transmit a request signal even if a portable device does not exist in a specific area of the vehicle. However, it is wasteful in terms of time and power to transmit all the information necessary for each periodic authentication every time. Further, when the answer signal from each portable device is transmitted with a time delay for each registered portable device so that interference does not occur, more time is required for communication and authentication.

  Therefore, the answer signal of each portable device is transmitted at the same time, and the vehicle-mounted device 10 suppresses communication time and power because there is no need to retry communication from the beginning if it is judged not only by verification of communication signal data but also by reception strength. be able to.

  Next, a communication method when the user approaches a specific area of the vehicle (for example, an area near the door when unlocking the door) with both of the registered portable devices 40A and 40B in hand is illustrated. 2 and FIG.

  FIG. 2 shows the communication timing along the time when the portable devices 40A and 40B registered by the user in a specific area of the vehicle are possessed. FIG. 3 is a flowchart showing a determination of whether or not to transmit the second request signal after transmitting the first request signal.

  In order to determine whether or not the registered portable devices 40A and 40B are approaching a specific area, the CPU 13 of the vehicle-mounted device 10 periodically sends the first request signal 101 as shown in FIG. Transmit (step 201).

  The portable device 40A that has received the first request signal 101 transmits a first answer signal 411 corresponding to the signal, as shown in FIG. The portable device 40B that has received the same first request signal 101 transmits the same first answer signal 421 as the portable device 40A at the same timing as shown in FIG.

  Here, when different portable devices 40A and 40B transmit the first answer signals 411 and 421 at the same time, a time difference in transmission timing occurs due to variations in the accuracy of the individual, and noise occurs in the data received by the receiver 20, There is a possibility that the first answer signals 411 and 421 cannot be received normally.

  Therefore, even if a time difference occurs in the received signal, as shown in FIG. 2D, the CPU 13 of the vehicle-mounted device 10 can receive an answer signal having a lower frequency than the data signal of the portable device at the normal time. Transmits a control signal to the LPF changing unit 24 of the receiver 20 at a timing after the first request signal 101 is transmitted and before the first answer signal is received. The filter circuit is switched to the low-pass filter (LPF2) 23 side having a cutoff frequency at which a low frequency can be received (step 202).

  Further, as shown in FIG. 2 (d), the CPU 13 of the vehicle-mounted device 10 receives the normal portable device data signal again at the timing when the first answer signal reception period has passed. A control signal is sent to the LPF changing means 24 of the device 20, and the LPF changing means 24 switches the filter circuit to the low-pass filter (LPF1) 22 side having a cut-off frequency at which a high frequency can be received (steps 204 and 206). ).

  Next, the vehicle-mounted device 10 determines whether or not the first answer signal has been normally received (step 203). That is, the CPU 13 receives the first answer signals 411 and 421 transmitted at the same timing, collates the received first answer signal 411 with the first answer signal stored in the memory 15, If they match (YES in step 203), the second request signal 102 for identifying the registered portable device number is transmitted (step 205).

  The portable device 40A that has received the second request signal 102 transmits a second answer signal 412 corresponding to the signal. The portable device 40B having received the same second request signal 102 and whose registration order is later is the time unique to the portable device number that does not overlap the second answer signal 422 that is the same as the portable device 40A. It transmits at the timing when it has passed (for example, 5 ms).

  The CPU 13 of the vehicle-mounted device 10 receives the second answer signal 412 and the second answer signal 422 transmitted at different timings, transmits the second request signal 102, and then stores the second answer signal 412 stored in the memory 15. Are compared with the received second answer signal 412. If they match, the third request signal 103 for authenticating the registered portable device is transmitted to the detected specific portable device 40A.

  The portable device 40A that has received the third request signal 103 compares the signal with the portable device number stored in the memory 43, and if it matches, the portable device 40A corresponds to the third request signal 103. The third answer signal 413 including the ID unique to the portable device is transmitted.

  The CPU 13 of the vehicle-mounted device 10 decodes the received third answer signal 413, and if the ID of the portable device 40A stored in the memory 15 matches and authentication by encrypted communication is established, for example, near the door When there is an input from the switch 31 mounted on the PC, unlock control is performed.

  As described above, since the first answer signals 411 and 421 can be transmitted simultaneously from the plurality of portable devices 40A and 40B, the waiting time until the first answer signal responds is shortened, and the communication time, The authentication time can be shortened, and as a result, power consumption can be suppressed.

Embodiment 2. FIG.
An electronic key device according to Embodiment 2 of the present invention will be described.

  In the first embodiment, the case where the vehicle-mounted device 10 can normally receive the signal at the timing of receiving the first answer signal is described. In the second embodiment, the first answer signal is received. When the on-vehicle device 10 cannot receive normally due to noise in the received signal despite normal transmission, or the result of collating the registered first answer signal with the received first answer signal If they do not match, if the degree of similarity is high as determined by decoding the received first answer signal, it is determined that the first answer signal has been received (YES in step 207), and the second request signal 102 is transmitted. (Step 205).

  In the second embodiment, a method for determining the similarity of the answer signal similarity determination unit 14 operating on the CPU 13 of the vehicle-mounted device 10 will be described.

  The CPU 13 of the vehicle-mounted device 10 generates a plurality of cycles (for example, six cycles) of ON / OFF signals having a frequency (1.6 kHz) that allows the portable device 40A to be distinguished from background noise at a higher frequency than the data signal as the first answer signal 411. ) When transmitted, if a signal having a plurality of cycles (for example, 6 cycles) is normally received (YES in step 203), the second request signal 102 is transmitted. Even if the signal cannot be normally received, the answer signal similarity determination unit 14 determines the similarity between the first answer signal stored in the memory 15 and the received first answer signal 411 (step 207).

  That is, if a signal having a similarity value of a prescribed value (for example, 4 cycles) can be received during the reception period of the first answer signal 411, the answer signal similarity determination unit 14 resembles the first answer signal 411. Is determined (YES in step 207), and the second request signal 102 is transmitted (step 205). What is necessary is just to set the frequency to be used, the period to transmit, and the period to determine according to the system to be used and a use environment.

  By this procedure, it becomes possible to avoid the phenomenon that the signal from the portable device 40A that has responded normally cannot be detected. Even if it is erroneously determined that there is a mobile device that is not actually registered, there is no problem because a malfunction caused by erroneous determination is not caused by the signals responded by the second request signal 102 and the third request signal 103.

  The present invention can be used not only for vehicles such as automobiles but also for similar electronic key devices such as two-wheeled vehicles, ships, and aircrafts.

It is a figure which shows the structure of the electronic key apparatus which concerns on Embodiment 1 and Embodiment 2 of this invention. It is a timing chart which shows operation | movement of the electronic key apparatus which concerns on Embodiment 1 and Embodiment 2 of this invention. It is a flowchart which shows operation | movement of the onboard equipment of the electronic key apparatus which concerns on Embodiment 1 and Embodiment 2 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Onboard equipment, 11 Transmission antenna, 12 Transmission / reception means, 13 CPU, 14 Answer signal similarity determination means, 15 Memory, 16 Drive means, 20 Receiver, 21 Reception antenna, 22 Low-pass filter, 23 Low-pass filter, 24 LPF change means , 30 control device, 31 switch, 40A portable device, 40B portable device, 41 transmission / reception means, 42 CPU, 43 memory, 44 battery.

Claims (2)

By communicating between the mounting device mounted on the vehicle and the portable device existing in the specific area of the vehicle, when the mounting device authenticates the ID code of the portable device, the control device mounted on the vehicle In the electronic key device to be operated,
A first low-pass filter mounted on a vehicle and having a cut-off frequency capable of receiving high frequencies, a second low-pass filter having a cut-off frequency capable of receiving low frequencies, and the first low-pass filter and the second low-pass filter A receiver including LPF changing means for switching a low-pass filter;
After transmitting the request signal periodically, an on-board device that controls the LPF changing means of the receiver and switches the filter of the receiver to the second low-pass filter side;
A plurality of portable devices that simultaneously transmit the same answer signal when receiving the request signal;
The mounting device receives the answer signal at the same time through the second low-pass filter of the receiver. The mounting device is
When the portable device transmits a predetermined waveform signal having a predetermined frequency as the answer signal for the first plurality of periods, the second waveform having a predetermined waveform signal having the predetermined frequency that is less than the first plurality of periods. 2. The electronic key device according to claim 1, further comprising an answer signal similarity determination unit that determines that the answer signal has been normally received when the answer signal is successfully received.

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