JP2020041412A - Portable machine - Google Patents

Abstract

To provide a portable machine which can reduce current consumption.SOLUTION: A motion sensor 34, which can detect motion of an own key, is built in a portable machine 3. A microcomputer 31 sets a sampling speed, when motion of the portable machine 3 is detected by the motion sensor 34, based on occurrence or non-occurrence of reception of a polling signal by a LF reception circuit 32. When the polling signal is not received by the LF reception circuit 32, the sampling speed of the motion sensor 34 is set to a low speed, and when the polling signal is received, the sampling speed is set to a high speed. The motion sensor 34 can detect occurrence or non-occurrence of oscillation of the portable machine 3 when the sampling speed is set to the low speed, and can detect pre-determined motion of the portable machine 3 when the sampling speed is set to the high speed. Current consumption can be reduced compared to a constitution for always performing high speed sampling.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a portable device possessed by a user.

  A vehicle to which a so-called smart key system (registered trademark) is applied performs key authentication by bidirectional communication with a portable device owned by a user, and unlocks a door on condition that key authentication is established. . As an example, a vehicle transmits an LF signal from a transmitter to form an LF area around a door in order to monitor the approach of a portable device. When the user having the portable device enters the LF area, an RF signal is returned from the portable device in response to the LF signal. The vehicle analyzes the RF signal and, when key authentication is established, permits unlocking of the door. At this time, when the user touches the door handle, the door is actually unlocked.

  In order to prevent fraudulent acts using the repeater, an acceleration sensor is built into the portable device, and when the acceleration sensor detects that the portable device is vibrating, reception of the LF signal is permitted, and the absence of the portable device vibration is detected. A technique has been proposed in which the reception of the LF signal is not permitted in such a case (for example, see Patent Documents 1 to 3).

  In addition, a technology has been proposed in which a user's motion is detected by an acceleration sensor built into the portable device, and when a predetermined motion is detected, the vehicle is operated or the user's motion is used as an authentication condition. (See, for example, Patent Documents 4 and 5).

JP-T-2015-510178A JP 2014-190046 A JP 2014/091434 A JP 2011-000903 A JP 2010-275701 A

  When different applications are realized by the same acceleration sensor, by setting the sampling speed in accordance with the application requiring high-speed sampling, it is possible to cope with low-speed sampling applications. However, if high-speed sampling is always performed, current consumption increases, and the battery life of the portable device is shortened.

  The present invention has been made in view of such a problem, and an object of the present invention is to provide a portable device capable of reducing current consumption.

  A portable device that solves the above-mentioned problem is a portable device owned by a user, a motion sensor capable of detecting a movement of the portable device, a receiving unit capable of receiving a polling signal transmitted from a device, and a receiving unit configured to receive the polling signal. The gist of the invention is to include a control unit that sets a sampling speed when the motion sensor detects the movement of the portable device based on whether or not a polling signal is received.

  According to this configuration, it is possible to individually set the sampling speed of the motion sensor when the portable device is around the device and when it is not. For example, when the portable device is near the device, the sampling speed is set to high, and when the portable device is not near the device, the sampling speed is set to low. As a result, current consumption can be reduced as compared with a configuration in which high-speed sampling is always performed.

  Regarding the portable device, the control unit sets the sampling speed to be lower than when the polling signal is received by the receiving unit when the polling signal is not received, and the motion sensor sets the sampling speed to be lower than when the polling signal is received. When the speed is set to be low, the presence or absence of vibration of the portable device may be detectable.

  According to this configuration, it is possible to individually set the validity and invalidity of the polling signal receiving function when the portable device is not around the device and when there is no vibration of the portable device. For example, the function of receiving a polling signal is enabled when the motion sensor detects the presence of vibration of the portable device, and the function of receiving the polling signal is disabled when the absence of vibration of the portable device is detected. As a result, current consumption can be reduced as compared with a configuration in which the polling signal reception function is always enabled.

  Regarding the portable device, the control unit sets the sampling speed to be higher when the polling signal is received by the receiving unit than when the polling signal is not received. When the mobile device is set at a high speed, a predetermined movement of the portable device may be detected.

  According to this configuration, when the portable device is near the device, the movement of the portable device can be accurately grasped. Thereby, when the movement of the user is used as the authentication condition, the effect of the countermeasure for preventing the fraud using the repeater can be improved.

  Regarding the portable device, the control unit may include a function of receiving the polling signal by the receiving unit when the receiving unit does not receive the polling signal and the motion sensor detects no vibration of the portable device. May be transited to a standby mode in which is invalidated.

According to this configuration, it is possible to prevent a relay attack (an improper act using a repeater) for a portable device that is stationary outside the vicinity of the device.
In the portable device, when the motion sensor detects the presence of vibration of the portable device during the standby mode, the control unit transitions to an operation mode for enabling the receiving function of the polling signal by the receiving unit. It may be that.

  According to this configuration, when a portable device that is initially stationary other than around the device is carried, a polling signal can be received, and the polling signal is actually received around the device. This makes it possible to individually set the sampling speed of the motion sensor based on whether or not a polling signal has been received.

  According to the present invention, current consumption can be reduced.

FIG. 2 is a block diagram showing a configuration of a smart key system. The state transition diagram of a portable machine.

Hereinafter, an embodiment of the portable device will be described.
As shown in FIG. 1, the smart key system (registered trademark) 1 performs key authentication by bidirectional communication between the vehicle 2 and the portable device 3, and unlocks the door on condition that the key authentication is established. I do.

  The vehicle 2 has an LF antenna 22 that can transmit an LF signal (for example, an LF band radio wave) and an RF that can receive an RF signal (for example, a UHF band radio wave) in addition to the verification ECU 21 that controls the security of the vehicle. The tuner 23 is provided. The vehicle 2 corresponds to a device.

  The collation ECU 21 transmits a polling signal from the LF antenna 22 to form an LF area around the door in order to monitor the approach of the portable device 3 to the vehicle 2. When the user having the portable device 3 enters the LF area, a response signal including a key code unique to the portable device 3 is returned from the portable device 3 in response to a polling signal.

  When the response signal is received by the RF tuner 23, the verification ECU 21 analyzes the response signal. The key code of the portable device 3 is registered in the verification ECU 21. The collation ECU 21 performs collation with a registered key code when analyzing the response signal. The collation ECU 21 permits unlocking of the door when the key authentication is established by collating and matching the key code. At this time, when the user touches the door handle, the door is actually unlocked.

  The portable device 3 includes, in addition to the microcomputer 31 that controls the overall control of its own key, an LF receiving circuit 32 that can receive an LF signal, and an RF transmitting circuit 33 that can transmit an RF signal. The LF receiving circuit 32 corresponds to a receiving unit. When the LF receiving circuit 32 receives the polling signal, the microcomputer 31 transmits a response signal including a key code unique to the portable device 3 from the RF transmitting circuit 33.

  The portable device 3 of the present embodiment has a built-in motion sensor 34 capable of detecting the movement of its own key. The microcomputer 31 sets the sampling speed when the motion sensor 34 detects the movement of the portable device 3 based on whether or not the LF receiving circuit 32 has received the polling signal. The microcomputer 31 corresponds to a control unit. In this example, when the LF receiving circuit 32 does not receive the polling signal, the sampling speed of the motion sensor 34 is set to low speed, and when the polling signal is received, the sampling speed is set to high speed. The motion sensor 34 can detect the presence or absence of vibration of the portable device 3 when the sampling speed is set to a low speed, and when the sampling speed is set to a high speed, the motion of the portable device 3 is determined in advance. For example, it is possible to detect a motion associated with a combination of bending and stretching motion and stationary motion).

  When detecting a predetermined movement of the portable device 3 through the motion sensor 34, the microcomputer 31 transmits an operation completion signal including an operation code for instructing an opening operation of the slide door and a key code of the portable device 3 to the RF transmission circuit 33. Send from. When the RF tuner 23 receives the operation completion signal, the verification ECU 21 of the vehicle 2 analyzes the operation completion signal, and when key authentication is established, receives the instruction by the operation code and opens the slide door. .

Next, the operation of the portable device 3 will be described.
As shown in FIG. 2, the microcomputer 31 makes a state transition between [A] to [C]. State [A] is a state in which the sampling speed of the motion sensor 34 is low and the function of receiving the polling signal by the LF receiving circuit 32 is invalid (sleep). The state [B] is a state in which the sampling speed of the motion sensor 34 is low and the function of receiving the polling signal by the LF receiving circuit 32 is valid (active). State [C] is a state in which the sampling speed of the motion sensor 34 is high and the function of receiving the polling signal by the LF receiving circuit 32 is valid (active). State [A] is a standby mode in which the LF reception function is disabled, and states [B] and [C] are operation modes in which the LF reception function is enabled.

  The microcomputer 31 maintains the state [A] in the state [A] unless the motion sensor 34 detects an acceleration equal to or greater than the threshold. When the absence of vibration of the portable device 3 is detected by detecting no acceleration equal to or greater than the threshold value by the motion sensor 34, it is suggested that the portable device 3 is stationary. On the other hand, when the motion sensor 34 detects an acceleration equal to or larger than the threshold value in the state [A], the microcomputer 31 makes a transition to the state [B]. When the motion sensor 34 detects an acceleration equal to or greater than the threshold value and the presence of vibration of the portable device 3 is detected, it is suggested that the user carrying the portable device 3 is walking. In the state [A], whether or not LF is received does not affect the state transition.

  In the state [B], the microcomputer 31 maintains the state [B] unless an acceleration equal to or greater than the threshold is detected by the motion sensor 34 and the LF receiving circuit 32 does not receive a polling signal. When the acceleration equal to or greater than the threshold is detected by the motion sensor 34 and the polling signal is not received by the LF receiving circuit 32, it is suggested that the user of the portable device 3 is walking outside the LF area. On the other hand, the microcomputer 31 makes a transition to the state [A] when the motion sensor 34 does not detect an acceleration equal to or greater than the threshold value in the state [B]. When the acceleration equal to or larger than the threshold value is no longer detected in the state [B], it is suggested that the portable device 3 which has been carried up to that time has been left still again or the user carrying the portable device 3 has stopped walking. On the other hand, when the LF receiving circuit 32 receives the polling signal in the state [B], the microcomputer 31 makes a transition to the state [C]. When the LF receiving circuit 32 receives the polling signal, it is suggested that the user having the portable device 3 has entered the LF area.

  The microcomputer 31 maintains the state [C] as long as the LF signal is received by the LF receiving circuit 32 in the state [C]. When the LF signal such as the polling signal is received in the state [C], it is suggested that the user having the portable device 3 is still in the LF area. In the state [C], the magnitude of the acceleration detected by the motion sensor 34 has no relation to the state transition. On the other hand, when the LF signal is not received by the LF receiving circuit 32 in the state [C], the microcomputer 31 makes a transition to the state [B]. When the LF signal is no longer received in the state [C], it is suggested that the user having the portable device 3 has left the area other than the LF area.

  Based on the above, when the portable device 3 is outside the LF area, the sampling speed of the motion sensor 34 is set to a low speed (state [A] and state [B]), and when the portable device 3 is within the LF area, The sampling speed of the sensor 34 is set to a high speed (state [C]). Thus, when the user carrying the portable device 3 performs a combination of the bending and stretching motion and the stationary motion in the LF area, the motion sensor 34 detects a predetermined motion, and the portable device 3 transmits an operation completion signal. You. As a result, the slide door automatically opens upon receiving the operation completion signal.

As described above, according to the present embodiment, the following effects can be obtained.
(1) The sampling speed of the motion sensor 34 is set individually when the portable device 3 is in the LF area and when it is not. In this example, when the portable device 3 is in the LF area, the sampling speed is set to high, and when the portable device 3 is not in the LF area, the sampling speed is set to low. As a result, current consumption can be reduced as compared with a configuration in which high-speed sampling is always performed.

  (2) The portable device 3 is usually left still at a place other than the LF area, such as the entrance of the house, and is taken out as necessary when the vehicle 2 is driven. That is, regarding the usage mode of the portable device 3, the time not in the LF area is longer than the time in the LF area. Therefore, by following the above (1) and setting the sampling speed to be low when the portable device 3 is not in the LF area, the power saving effect of the portable device 3 can be improved.

  (3) When the portable device 3 is not in the LF area, the validity and invalidity of the polling signal receiving function are set individually when the portable device 3 is vibrated and when it is not. In this example, when the motion sensor 34 detects that the portable device 3 is vibrated, the function of receiving the polling signal is enabled, and when the absence of the vibration of the portable device 3 is detected, the function of receiving the polling signal is disabled. Is done. As a result, current consumption can be reduced as compared with a configuration in which the polling signal reception function is always enabled.

  (4) As described in (2) above, most of the usage forms of the portable device 3 are settled at the entrance of the house or the like, and in this situation, the two-way communication with the vehicle 2 is not necessarily required. By disabling the LF receiving function according to the above (3) over such a long time, the power saving effect of the portable device 3 can be improved.

(5) In addition to the above (4), it is possible to prevent a relay attack (an illegal act using a repeater) with respect to the portable device 3 that is stationary outside the LF area.
(6) When the portable device 3 is in the LF area, the movement of the portable device 3 can be accurately grasped. Thereby, when the movement of the user is used as the authentication condition, the effect of the countermeasure for preventing the fraud using the repeater can be improved.

  (7) When the portable device 3 that has been initially stood outside of the LF area is carried, a polling signal can be received, and the polling signal is actually received in the LF area. Thus, the sampling speed of the motion sensor 34 can be individually set based on whether or not a polling signal has been received.

The above embodiment can be embodied with the following modifications.
-The motion sensor 34 may be an angular velocity sensor or a vibration sensor other than the acceleration sensor.

The low-speed sampling is desirably capable of detecting the presence or absence of vibration of the portable device 3, and the lower the speed, the lower the current consumption.
In the high-speed sampling, it is desirable that a predetermined movement of the portable device 3 can be detected. The higher the speed, the more accurately the movement of the portable device 3 can be grasped.

The sampling speed may be set to three or more stages according to the detection accuracy of the target of the movement of the portable device 3 to be detected.
The movement of the portable device 3 to be detected can be arbitrarily changed.

  -The device is not limited to the vehicle 2. The sampling speed at which the motion sensor 34 detects the movement of the portable device 3 may be set based on whether or not a polling signal transmitted from a building door or the like is received.

-The low frequency LF signal is not limited to the LF band radio wave.
-High-frequency RF signals are not limited to radio waves in the UHF band.

  DESCRIPTION OF SYMBOLS 1 ... Smart key system, 2 ... vehicle (equipment), 3 ... portable device, 21 ... collation ECU, 22 ... LF antenna, 23 ... RF tuner, 31 ... microcomputer (control means), 32 ... LF receiving circuit (receiving means) , 33 ... RF transmission circuit, 34 ... Motion sensor.

Claims (5)

In the portable device owned by the user,
A motion sensor capable of detecting the movement of the portable device;
Receiving means capable of receiving a polling signal transmitted from the device,
A portable device comprising: a control unit that sets a sampling speed when the motion sensor detects the movement of the portable device based on whether the polling signal is received by the receiving unit. The control means sets the sampling rate to be lower than when the polling signal is received, when the polling signal is not received by the receiving means,
The portable device according to claim 1, wherein the motion sensor is capable of detecting the presence or absence of vibration of the portable device when the sampling speed is set to a low speed. The control means, when the polling signal is received by the receiving means, sets the sampling speed higher than when the polling signal is not received,
The portable device according to claim 1, wherein the motion sensor is capable of detecting a predetermined movement of the portable device when the sampling speed is set to a high speed. The control unit is configured to, when the receiving unit does not receive the polling signal and the motion sensor detects that the portable device does not vibrate, disable a function of receiving the polling signal by the receiving unit. The portable device according to claim 1, wherein the portable device transits to a mode. 5. The control unit transits to an operation mode for enabling a function of receiving the polling signal by the receiving unit when the motion sensor detects vibration of the portable device during the standby mode. 6. Portable machine.