JP2013194439A - Electronic key device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic key device for enabling lock/unlock of a door even under noise circumstances by reliably determining whether a portable machine is inside/outside a vehicle.SOLUTION: An on-vehicle machine 10 includes inside-/outside-vehicle determining means 133 for determining whether a portable machine 100 is inside/outside a vehicle from a measurement result of the intensity of a signal transmitted from the portable machine, and noise determining means 131 for performing determination of whether the portable machine, when determined to be inside the vehicle, is under noise circumstances or not. The noise determining means determines that the portable machine is under noise circumstances in the case that the intensity of the signal is a specified value or higher when an authentication request signal is not transmitted from the on-vehicle machine, and a difference between the intensity of the signal and the intensity of a signal from each inside-vehicle antenna compared with each other is within a predetermined value. A determination logic changing means 134 is provided for changing the determination logic of door control when the portable machine is under noise circumstances, thus enabling lock/unlock of the door even under noise circumstances.

Description

  The present invention relates to an electronic key device that performs authentication by collating an ID code through communication between an in-vehicle device and a portable device, and performs locking and unlocking of a door.

  As a conventional technique for locking and unlocking a door of a vehicle, there is a technique in which a user inserts a key into a keyhole and rotates it, or an electronic key device for a vehicle using a so-called FOB key. The latter electronic key device for vehicles performs wireless communication between the in-vehicle device and the portable device without touching the key at all in the user's pocket or bag, and the ID code from the portable device is mounted on the vehicle. Check the code stored in the machine.

  Such an electronic key device for a vehicle is called a keyless entry system, and the ID code is collated by wireless communication without operating the key, and when the collation result matches, only the sensor or button attached to the door knob is touched. Thus, the vehicle-mounted device can lock and unlock the door. (For example, refer to Patent Document 1 and Patent Document 2).

JP 2010-181295 A JP 2006-108981 A

However, the prior art has the following problems.
The keyless entry system described in Patent Document 1 measures the signal strength of a signal received during a period in which the keyless entry system is not communicating, holds the measured value as a noise component, and is transmitted from an antenna during communication. The signal strength is corrected by subtracting the noise component from the obtained signal strength, and the distance from the antenna is obtained. However, depending on the noise component, the antenna cannot be completely corrected by simply reducing it by radio wave interference with the noise source. In some cases, it may be determined that the portable device in the vehicle is outside the vehicle and confinement may occur.

  The keyless entry system described in Patent Document 2 counts if the signal strength of a signal received at regular intervals is equal to or greater than a specified value, and determines that noise has been received if the count value is equal to or greater than the specified value. It stores time information and noise information. When a failure occurs, it is possible to determine whether the noise was caused by the diagnostic tool, but it will occur as a failure due to noise.

  In general, in the smart keyless entry system, authentication is started by pressing a request switch provided on the door knob, and when the authentication is established, the door is locked and unlocked. However, due to the interference with the radio wave used in the vehicle detection device for coin parking, the authentication of the electronic key may not be established and the door may not be locked and unlocked. This will be described below.

  Here, FIG. 5 describes the timing for measuring the signal transmission timing of the signal transmitted from each antenna and the signal intensity of the signal measurement LF (Low Frequency) signal after the request switch mounted on the doorknob is pressed. It is a time chart which shows an authentication pattern.

As shown in FIG. 5 (a), when a user holding a portable device pushes a request switch on the door handle to lock the door, the vehicle exterior antenna of the in-vehicle device is portable as shown in FIG. 5 (b). LF communication signal including a unique ID for starting and calling and a control command is transmitted. Subsequently, in order to determine whether the portable device is inside or outside the vehicle, the portable device transmits an LF signal for signal strength measurement for measuring the distance from the antenna outside the vehicle.
As shown in FIG. 5E, the portable device starts receiving the LF communication signal and measures the signal strength at timing A at which the LF signal for signal strength measurement is transmitted.

Following the transmission from the antenna outside the vehicle, as shown in FIG. 5C, the vehicle interior antenna a of the vehicle-mounted device transmits an LF signal for signal strength measurement for measuring the signal strength.
The portable device measures the signal strength from the in-vehicle antenna a at the timing B at which the LF signal for signal strength measurement is transmitted, as shown in FIG. Similarly, as shown in FIG. 5D, a signal strength measurement LF signal for measuring the signal strength is also transmitted from a different in-vehicle antenna b, and the portable device measures the signal strength at timing C. The portable device responds to the in-vehicle device with the measured signal strength with an RF (Radio Frequency) signal.
In addition, the above-mentioned LF communication signal and signal strength measurement LF signal are used as authentication request signals.

The in-vehicle device performs in-vehicle / out-of-vehicle determination based on the signal strength from each antenna measured by the portable device in order to control door locking / unlocking. The first determination logic includes the following condition A & condition B & condition C It becomes.
Condition A In-vehicle antenna measurement signal intensity> In-vehicle antenna determination threshold Condition B In-vehicle antenna a measurement signal intensity <In-vehicle antenna a determination threshold Condition C In-vehicle antenna b measurement signal intensity <In-vehicle antenna b determination threshold Each determination threshold is matched to the area of the car Can be set.
In other words, the first determination logic is logic that enables the door to be locked and unlocked if the portable device is in the determination area outside the vehicle and not in the determination area in the vehicle.

  If it is not in a noise environment, the door can be unlocked and unlocked according to the first determination logic. However, even if the portable device is outside the vehicle in the noise environment, the vehicle detection device used in coin parking is used. If the transmitted radio wave uses a frequency that is close to the radio frequency used in the communication of the electronic key device, the signal strength of the vehicle detection device is erroneously determined as the signal strength of the vehicle interior antenna. Antenna a measurement signal strength ≧ in-vehicle antenna a determination threshold, and in condition C, it is determined that in-vehicle antenna b measurement signal strength ≧ in-vehicle antenna b determination threshold, and it is erroneously determined that the portable device is in the vehicle. Despite all possible conditions, the door control will not work.

  The present invention has been made to solve the above-described problems. The presence of another system having a radio frequency that is close to the radio frequency used for communication of the electronic key device can reduce the influence of the radio wave. An object of the present invention is to obtain an electronic key device capable of reliably locking and unlocking a door even under a noise environment.

  The electronic key device according to the present invention is mounted on a vehicle when the vehicle-mounted device authenticates the ID code of the portable device by communicating between the vehicle-mounted device mounted on the vehicle and the portable device owned by the user. In the electronic key device that locks and unlocks the door, the portable device transmits the request signal for authentication transmitted from the antenna of the vehicle-mounted device, the signal strength of the request signal, and the request signal. Signal strength measuring means for measuring the signal strength when there is no signal, and transmission means for transmitting the measurement result of the signal strength to the in-vehicle device. A vehicle inside / outside determination unit that determines whether the vehicle is inside or outside the vehicle, and a noise determination unit that determines whether the portable device is in the vehicle when the inside / outside vehicle determination unit determines that the portable device is inside the vehicle. , Noise The means compares the signal strength when the request signal is not transmitted with a specified value or more, compares the signal strength with the signal strength from each in-vehicle antenna, and the difference is within a predetermined value. It is characterized by judging that it exists in.

  According to the electronic key device according to the present invention, for example, a vehicle detection device such as a coin parking that uses a radio wave close to a frequency used for communication between the in-vehicle device and the portable device, and authentication communication by radio wave interference between the device and this device. In order to prevent the function of locking and unlocking the door from being impaired due to failure, the signal strength of the LF communication signal transmitted from the antenna of the in-vehicle device during communication is measured, and the inside / outside determination is performed from the measurement result. In addition to the determination method to be performed, even if it is determined that the authentication is not established, the noise determination is performed from the measurement result of the signal strength and the signal strength when the LF signal is not transmitted. Also, the authentication response can be ensured.

Also, if it is determined that the environment is not in a noise environment, it operates without compromising the authentication response, and if it is determined that the environment is in a noise environment, the determination logic is changed to ensure that the door is locked and unlocked. An electronic key device can be obtained.
Moreover, when it determines with it being under a noise environment, the electronic key apparatus which can eliminate the influence of noise and can implement locking / unlocking of a door reliably by switching the transmission pattern of authentication communication can be obtained.

It is a conceptual diagram of the whole system containing the electronic key apparatus in Embodiment 1 of this invention. It is a figure which shows the time chart which shows the 1st authentication pattern which is a transmission pattern of each antenna containing the electronic key apparatus in Embodiment 1 of this invention. It is a conceptual diagram of the whole system containing the electronic key apparatus in Embodiment 2 of this invention. It is a figure which shows the time chart which shows the 2nd authentication pattern which is a transmission pattern of each antenna containing the electronic key apparatus in Embodiment 2 of this invention. It is a figure which shows the time chart which shows the transmission pattern of each antenna regarding description of the subject of this invention.

Embodiment 1 FIG.
A preferred embodiment of the electronic key device according to Embodiment 1 of the present invention will be described below with reference to FIGS.
FIG. 1 is a conceptual diagram of an entire system including an electronic key device according to Embodiment 1 of the present invention. The electronic key device in FIG. 1 includes an in-vehicle device 10 mounted at a predetermined location of a vehicle and portable devices 100 and 101 owned by a user who communicates with the in-vehicle device 10. The portable device 100 and the portable device 101 have the same configuration, and are shown as portable devices owned by each person when a vehicle is shared and used by a plurality of people, only with different key numbers and ID codes. (Hereinafter, only the portable device 100 will be described).

The in-vehicle device 10 includes a first transmission unit 11 and a second transmission unit 12, a first CPU 13, a first memory 14, and a drive unit 15 that drives locking / unlocking of the door.
A plurality of vehicle exterior antennas 21 are connected to the first transmission means 11, and two vehicle interior antennas 22 a and 22 b (for example, subscripts are omitted when collectively referred to) are connected to the second transmission means 12. An RF receiver 23 for receiving a signal from the portable device 100 is connected to the first CPU 13, and an RF receiving antenna 24 is connected to the RF receiver 23. The driving means 15 is connected to the first CPU 13 and controls driving of a vehicle control device 25 such as a door lock motor. The in-vehicle device 10 is connected to a request switch 26 that is a door locking / unlocking device provided in a door knob of the vehicle.

The first CPU 13 includes a noise determination unit 131, a first reception unit 132, a vehicle inside / outside determination unit 133, and a determination logic change unit 134. The vehicle inside / outside determination unit 133 detects the distance between the antennas 21 and 22 and the portable device 100 from the signal strength measurement result from the portable device 100 received by the first receiving unit 132, and the portable device 100 is in the vehicle. When the portable device 100 is determined to be inside the vehicle by the vehicle inside / outside determination unit 133, the noise determination unit 131 determines whether the electronic key device is in a noise environment. . If it is determined that the electronic key device is in a noise environment, the determination logic changing unit 134 changes the determination logic.
The first memory 14 stores a Wake Up ID 141, KeyNos 142A and 142B, and Key IDs 143A and 143B for each portable device.

On the other hand, the portable device 100 includes a reception IC 110 that receives RF signals from the vehicle exterior antenna 21 and the vehicle interior antenna 22 of the vehicle-mounted device 10, a second CPU 120 connected to the reception IC 110, and a second CPU 120 connected to the second CPU 120. 3 transmission means 130 and a battery 140 for operating the portable device 100.
The reception IC 110 has activation means for activating the second CPU 120 in response to the LF signal for the authentication request including the Wake Up ID from the in-vehicle device 10 received via the LF reception antenna 111. .
The second CPU 120 includes a Key ID and Key No. for performing unique identification of the signal strength measuring means 121 and the portable device 100. Is stored in the second memory 122 and the second receiving means 123 for receiving the LF signal from the in-vehicle device 10.

The second receiving means 123 receives the request signal for authentication transmitted from the vehicle exterior antenna 21 of the in-vehicle device 10 received via the LF reception antenna 111 and the LF signal transmitted from the vehicle interior antenna 22 for measuring the signal strength. Receive. The signal strength measuring unit 121 measures the signal strength of the request signal received from the in-vehicle device 10 received by the second receiving unit 123 and the signal strength when the request signal is not transmitted.
The third transmission unit 130 transmits the measurement result of the signal strength measured by the signal strength measurement unit 121 to the in-vehicle device 10 as an RF signal via the RF transmission antenna 139.

Next, functions and a series of operations of each component of the in-vehicle device 10 and the portable device 100 having these components will be described with reference to FIGS. 1 and 2.
FIG. 2 is a time chart showing a timing for measuring the transmission timing of each antenna and the signal strength of the signal measurement LF signal after the request switch 26 is pressed, and is a first authentication pattern.
First, normal operations performed by the in-vehicle device 10 and the portable device 100 will be described.

[Normal procedure 1]
When the authorized user presses the request switch 26 provided on the door of the vehicle as shown in FIG. 2A, the in-vehicle device 10 confirms whether or not the portable device 100 registered near the vehicle is present. Therefore, authentication of the portable device 100 is started.
[Normal procedure 2]
As shown in FIG. 2 (b), the first CPU 13 in the in-vehicle device 10 sends an LF communication signal for an authentication request from the first transmission means 11 to the side where the request switch 26 mounted on the vehicle is pressed. For example, the transmission is performed via the vehicle exterior antenna 21 provided in the door knob.
[Normal procedure 3]
On the other hand, the second receiving means 123 in the portable device 100 receives the LF signal via the LF receiving antenna 111 and the receiving IC 110.

[Normal procedure 4]
Next, the second CPU 120 generates a response signal including a unique ID code that it has in advance in response to the LF signal corresponding to the authentication request received via the second receiving means 123.
After the transmission of the LF communication signal is completed, the in-vehicle device 10 transmits a signal strength measurement LF signal for measuring the communication strength of the LF signal in order to detect the position of the portable device 100 as shown in FIG. To do.
The portable device 100 detects the positions of the vehicle exterior antenna 21 and the portable device 100 at the signal strength measurement timing A as shown in FIG. 2C, the in-vehicle antenna 22a transmits only the signal strength measurement LF signal, and the portable device 100 detects the positions of the in-vehicle antenna 22a and the portable device 100 at the signal strength measurement timing B. Similarly, as shown in FIG. 2 (d), this is also applied to the in-vehicle antenna 22 b, and the signal strength measuring means 121 of the portable device 100 measures the signal strength of the LF signal for measuring the signal strength from each of the antennas 21 and 22. A response signal is generated.
Although the description has been made with two in-vehicle antennas 22 this time, the number of antennas that can be detected in the vehicle may be adjusted according to the vehicle.

[Normal procedure 5]
Next, the second CPU 120 of the portable device 100 transmits the generated response signal to the in-vehicle device 10 as an RF signal via the third transmission unit 130 and the RF transmission antenna 139.
[Normal procedure 6]
On the other hand, the first CPU 13 in the in-vehicle device 10 receives an RF signal that is a response signal via the RF receiving antenna 24 and the RF receiver 23.

[Normal procedure 7]
Then, the first CPU 13 authenticates whether or not the ID code included in the RF signal acquired by the first receiving unit 132 matches the ID code stored in advance.
[Normal procedure 8]
Furthermore, when the in-vehicle / out-of-vehicle determining means 133 of the first CPU 13 determines from the signal strength information included in the RF signal that the registered portable device 100 exists in the out-of-vehicle area and does not exist in the in-vehicle area, the normal procedure is performed. The operation of the request switch 26 in No. 1 is determined to be an operation by an authorized user, and the control device 25 is operated via the driving unit 15 to perform door locking / unlocking.

[Normal procedure 9]
On the other hand, when it is determined that the portable device 100 does not exist in the vehicle outside area (is in the vehicle), the driving unit 15 determines that the operation of the request switch 26 in the normal procedure 1 is not an operation by the authorized user, and performs control. Conventionally, the processing has been completed without operating the device 25.

  Therefore, if the signal intensity of the noise is detected and determined to be in the in-car area due to radio noise such as coin parking at the stage of [normal procedure 8] even though the portable device 100 is not originally in the car, There was a problem that the door could not be locked and unlocked at the stage of step 9] even though a normal portable device was in the area outside the vehicle.

  Next, the electronic key device according to Embodiment 1 of the present invention that operates reliably even when a functional failure occurs due to radio wave interference of a device such as coin parking will be described with reference to FIG. .

2, the signal intensity measurement timing A of the portable device 100 is the same as that described with reference to FIG. 5, but in order to detect the position of the portable device 100 from the outside antenna 21 as shown in FIG. After transmitting the LF signal for measuring the signal strength for measuring the communication strength of the LF signal, the LF signal for measuring the signal strength is not transmitted from the in-vehicle antenna 22 and no LF signal is transmitted from any antenna. Leave blank.
The portable device 100 measures the signal strength at the signal strength measurement timing A ′ when no LF signal is transmitted from any antenna. Subsequent processing is the same as that described in FIG.

Although the transmission timing of the LF signal from the in-vehicle device 10 and the signal strength measurement timing of the portable device 100 are different from the conventional ones, the procedure from [Normal Procedure 1] to [Normal Procedure 8] is controlled by exactly the same procedure. To do.
Therefore, in a state that is not in a noise environment, although there is a delay of one signal strength measurement timing of the portable device, it is a difference of about 5 ms, and since it is not a time that can be experienced by humans, it does not impair responsiveness before the invention. It is possible to lock and unlock the door.

  Next, there was a situation in which the door could not be locked and unlocked due to the influence of noise even though the portable device 100 was in the outside area. In [Normal Procedure 9], the first determination logic entered the outside area. Even if it is determined that there is no legitimate portable device, that is, even if it is determined that there is a portable device in the vehicle, the first CPU 13 uses the noise determination means 131 to detect noise from the signal strength measurement result of the portable device 100. Improve the problem by implementing the judgment.

  As a method of the noise determination means, when the portable device 100 is outside the vehicle, if a response is returned to the vehicle exterior antenna 21, it is determined that it is in the vicinity of the vehicle exterior antenna because the radio wave has surely arrived. On the other hand, the signal strength measurement result of the portable device 100 with respect to the in-vehicle antenna 22a and the in-vehicle antenna 22b is not affected by the in-vehicle antennas 22a and 22b because the portable device 100 is outside the vehicle. The signal strength of the radio wave being used is measured.

  Further, the measurement result of the signal strength measurement timing A ′ of the portable device 100 is a timing at which the LF signal is not transmitted from the electronic key device (on-vehicle device 10), and this is also a radio wave used simply by coin parking. Is measured. That is, when the portable device 100 is present outside the vehicle and in the antenna area outside the vehicle, the measurement results at the signal intensity measurement timings A ′, B, and C of the portable device 100 are the same.

Therefore, the second determination logic is Condition A & Condition B & Condition C of the following conditions.
Condition A External antenna 21 measurement signal intensity> External antenna determination threshold Condition B Measurement signal intensity when electronic key device does not transmit LF signal> Noise determination
Threshold condition C In-car antenna 22a measured signal strength ≒ In-car antenna 22b measured signal intensity ≒ Measured signal intensity when electronic key device does not transmit LF (≒ indicates nearly equal to near equal)

As the above condition, the “nearly equal” may be set by setting the establishment threshold width in consideration of variations in measurement accuracy. The noise determination threshold value may be set to a threshold value that is not influenced by the vehicle internal / external determination area in consideration of the vehicle internal / external antenna determination threshold value. When this condition is satisfied, it can be determined that the user is in a noise environment.
That is, the noise determination means 131 has a signal strength that is not less than a specified value (noise determination threshold) when the electronic key device does not transmit a request signal (LF signal) for authentication, and the signal strength and each vehicle interior The signal intensities from the antennas 22a and 22b are compared, and when the difference is within a predetermined value, it is determined that the noise environment is present.

  Here, as a condition, although it is determined that the portable device 100 is in the vehicle, there is a concern that binding may occur by determining that the portable device 100 is out of the vehicle. It is rare that the measurement result of the two in-vehicle antennas is nearly equal, and the erroneous determination can be prevented by the condition that the measurement signal intensity when the LF signal is not transmitted is nearly equal.

  The determination method by the noise determination unit 131 has been described. Based on the determination result by the noise determination unit 131, the determination logic change unit 134 changes the door control from the first determination logic to the second determination logic. By performing door locking / unlocking when it is determined to be in the environment, it is possible to improve the problem of not operating due to the influence of noise while maintaining responsiveness.

  As described above, in the first embodiment, the in-vehicle device 10 successfully authenticates the ID code of the portable device 100 by communicating between the in-vehicle device 10 and the portable device 100 owned by the user. In addition, in the electronic key device that performs locking and unlocking of the door mounted on the vehicle, the in-vehicle device 10 includes, in addition to the first determination logic that performs the inside / outside determination based on the signal strength of the transmitted LF communication signal, If the first determination logic is not established, it is determined whether the current environment is a noise environment, and if it is determined that the current environment is a noise environment, the second determination logic is changed so that even in a noise environment. The door is unlocked and unlocked without fail.

Embodiment 2. FIG.
Next, a preferred embodiment of the electronic key device according to Embodiment 2 of the present invention will be described with reference to FIGS.
FIG. 3 is a conceptual diagram of the entire system including the electronic key device according to Embodiment 2 of the present invention. 3 differs from FIG. 1 of the first embodiment in that an authentication pattern switching unit 135 is provided instead of the determination logic changing unit 134 provided in the first CPU 13 of the in-vehicle device 10. Other configurations are the same as those in FIG. 1, and the same or corresponding parts are denoted by the same reference numerals and description thereof is omitted.

  In the invention of the first embodiment, the noise determination is performed, and when it is determined that the noise environment is determined, the explanation is made that the door can be locked and unlocked while maintaining the responsiveness. The invention of the second embodiment In this case, the responsiveness is impaired, but the malfunction including the prevention of confinement can be prevented more reliably.

  In the first authentication pattern described in FIG. 2, the signal strength measurement LF signal is transmitted from the in-vehicle antenna 22 to the portable device 100 wake-up by the in-vehicle antenna 21. Has mistakenly determined that the signal intensity that does not reach from the in-vehicle antenna 22 is in the vehicle. Therefore, the point of switching the authentication pattern is different from that of the first embodiment in order to confirm that the portable device 100 is in the vehicle.

  In the second embodiment, the contents up to the noise determination described in the first embodiment are the same, but when it is determined that the noise environment is present, the first authentication pattern described above is changed from the first authentication pattern described above. The authentication method is switched to the second authentication pattern, and the method will be described below with reference to FIG.

FIG. 4 shows the measurement of the transmission timing of each antenna to be transmitted and the signal strength of the signal measurement LF signal after the transmission of the LF signal shown in FIG. It is a time chart which described timing, and is a 2nd authentication pattern.
In this second authentication pattern, as shown in FIGS. 4A, 4B, and 4C, a unique ID and control for starting and calling the portable device from the outside antenna 21 and the inside antennas 22a and 22b. The difference is that the LF communication signal including the command is transmitted and the signal strength measurement LF signal is transmitted continuously to the LF communication signal.

  In FIG. 2, since the signal strength by each in-vehicle antenna 22 is measured for the portable device 100 wake-up by the LF communication signal of the outside antenna 21, the noise is generated even though the portable device 100 is not originally in the vehicle. However, as shown in FIG. 4, the LF signal is transmitted independently from the vehicle exterior antenna 21 and each of the vehicle interior antennas 22a and 22b, and the Wake Up is performed with the LF communication signal of each antenna. An erroneous determination can be prevented by measuring the signal strength of each of the inside and outside antennas 21 and 22 for the portable device 100.

In other words, the signal strength by the in-vehicle antennas 22a and 22b is measured including the influence of noise for the portable device 100 that is wake-up by the LF communication signal of the outside antenna 21, but the Wake by the LF communication signal of each in-vehicle antenna 22a and 22b In the case of up, when the portable device 100 is outside the vehicle, the LF communication signal from the in-vehicle antennas 22a and 22b does not reach the portable device 100, so Wake Up is not performed.
In other words, for example, signal intensity measurement LF signals transmitted after the LF communication signal of the antenna 21 outside the vehicle, for example, at the signal strength measurement timings B and C of the portable device 100 are not measured. Not receive. Therefore, after it is determined that the vehicle is not in the vehicle, authentication is established with the antenna outside the vehicle, so that the door can be locked and unlocked.

The reason why the signal strength by the in-vehicle antenna 22 is measured with respect to the portable device 100 wake-up by the LF communication signal of the outside antenna 21 as shown in FIG. 2 is because it takes time to transmit the LF communication signal from each antenna. There is a purpose to improve the response speed.
Since there are many scenes that are used outside the noise environment when used in a noise environment and outside the noise environment, the first authentication pattern with high responsiveness shown in FIG. If it is determined that the environment is a noise environment, the second authentication pattern is switched to reduce the responsiveness. However, the door cannot be locked and unlocked, and the function is effective.

As described above, in the second embodiment, the in-vehicle device 10 successfully authenticates the ID code of the portable device 100 by communicating between the in-vehicle device 10 and the portable device 100 owned by the user. The on-vehicle device 10 is an electronic key device that locks and unlocks a door mounted on a vehicle, and the in-vehicle device 10 is authenticated by a first authentication pattern that performs a vehicle inside / outside determination from the signal strength of the transmitted LF communication signal. If not, it is determined whether it is currently in a noise environment, and if it is determined that it is in a noise environment, switching to the second authentication pattern increases the responsiveness except under the noise environment, Then, the responsiveness is lowered, but the performance is improved as a function of locking and unlocking the door.
In addition, since the in-vehicle authentication communication can be reliably performed, it is possible to reliably prevent the confinement that erroneously determines inside and outside the vehicle and locks the door with the portable device in the vehicle.

10: In-vehicle device, 11: First transmission means,
12: 2nd transmission means, 13: 1st CPU,
14: first memory, 15: driving means,
21: Outside antenna, 22, 22a, 22b: Inside antenna,
23: RF receiver, 24: RF receiving antenna,
25: Control device, 26: Request switch,
131: Noise determining means, 132: First receiving means,
133: Inside / outside determination means 134: Determination logic changing means,
135: Authentication pattern switching means, 141: Wake Up ID,
142: Key No, 143: KeyID,
100, 101: portable device, 110: receiving IC,
111: LF receiving antenna, 120: second CPU,
121: Signal strength measuring means, 122: Second memory,
123: second receiving means, 130: third transmitting means,
139: RF transmitting antenna, 140: battery.

Claims (5)

By communicating between the vehicle-mounted device mounted on the vehicle and the portable device owned by the user, the vehicle-mounted device locks and unlocks the door mounted on the vehicle when the ID code of the portable device is authenticated. In an electronic key device that
The portable device has a receiving means for receiving a request signal for authentication transmitted from an antenna of the in-vehicle device, and a signal strength for measuring a signal strength of the request signal and a signal strength when the request signal is not transmitted. A measuring means, and a transmission means for transmitting the measurement result of the signal strength to the in-vehicle device,
The in-vehicle device has a vehicle inside / outside determination means for determining whether the portable device is in the vehicle or outside the vehicle from a signal intensity measurement result transmitted from the portable device, and the portable device is in the vehicle by the vehicle inside / outside determination means. When it is determined, it is provided with a noise determination means for performing a determination as to whether it is in a noise environment,
The noise determination means, when the signal strength when the request signal is not transmitted is a specified value or more, and the signal strength is compared with the signal strength from each in-vehicle antenna, and the difference is within a predetermined value The electronic key device is characterized in that it is determined to be in a noise environment.   The in-vehicle device has a plurality of vehicle exterior antennas and a transmission unit that transmits signals from the vehicle interior antenna, and the request signal for authentication transmitted from the transmission unit is used to activate and call the portable device from the vehicle exterior antenna. A signal strength measurement signal is transmitted following the LF communication signal including the unique ID and the control command and the signal, and the signal strength measurement signal is transmitted from the vehicle interior antenna following the transmission from the vehicle exterior antenna. The electronic key device according to claim 1, wherein the electronic key device is a signal of a first authentication pattern.   The in-vehicle device includes a determination logic changing unit that changes a determination logic for door control when the noise determination unit determines that the portable device is in the vehicle, and the determination logic is changed. 3. The electronic key device according to claim 1, wherein the door is locked and unlocked by changing means.   The in-vehicle device includes an authentication pattern switching unit that changes a pattern of authentication communication when the noise determination unit determines that the portable device is in the vehicle even when it is determined to be in a noise environment. The electronic key device according to claim 1 or 2. The authentication pattern switching means switches from the first authentication pattern to the second authentication pattern that transmits request signals for authentication from a plurality of in-vehicle antennas following transmission of the request signals for authentication from the antenna outside the vehicle. The electronic key device according to claim 4, which is configured as described above.

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