JP2019095372A - Vehicle system, on-vehicle device, and portable device - Google Patents

Abstract

To determine a position of a portable device even when a body of a vehicle is resinified, and more accurately determine that the portable device is present inside and outside a cabin.SOLUTION: An LF transmission antenna is arranged so that directions of magnetic field vectors are different with a borderline region between inside and outside of a cabin of a vehicle as a boundary, a portable device includes an RSSI measurement circuit which measures RSSI of an LF signal received from the LF transmission antenna, a vector direction specification part specifying the directions of magnetic field vectors of the LF transmission antenna and an RF transmission part replying a response signal including the RSSI and the directions of the magnetic field vectors, and BCM 30 includes a response acquisition part 303 which acquires the response signal replied from the RF transmission part and a position determination part 306 which performs inside and outside determination using not only the RSSI included in the response signal acquired by the response acquisition part 303 but also the directions of the magnetic field vectors, and determines a position of the portable device.SELECTED DRAWING: Figure 6

Description

  The present disclosure relates to a vehicle system that determines the position of a portable device using radio waves, and an on-vehicle device and a portable device used in the vehicle system.

  BACKGROUND Conventionally, there is known a technology for determining the position of a portable device using radio waves transmitted and received between a vehicle-mounted device and the portable device. For example, in Patent Document 1, the portable device is determined depending on which of the request signal from the antenna provided outside the vehicle and the request signal from the antenna provided in the vehicle interior is to be returned from the portable device. A technique is disclosed for determining where the vehicle is located inside or outside the vehicle cabin.

  Further, Patent Document 2 discloses a technique for determining the position of a portable device based on the RSSI of a request signal transmitted from antennas arranged at a plurality of locations of a vehicle. In Patent Document 2, the portable device measures the RSSI of the request signal transmitted from the antennas arranged at a plurality of locations of the vehicle, and transmits a response signal including the RSSI to the on-vehicle apparatus. Then, when the in-vehicle device acquires at least three RSSIs of request signals transmitted from different antennas, the position of the portable device is determined by the principle of triangulation based on those RSSIs.

JP 2000-145228 A Unexamined-Japanese-Patent No. 2016-12477

  In order to reduce the weight of the vehicle, it is conceivable that the body of the vehicle is resinified from metal, but when the body is resinified, radio waves are transmitted without being shielded by the body. Therefore, in the technique disclosed in Patent Document 1, the communication area of the antenna provided outside the vehicle and the communication area of the antenna provided in the vehicle room are difficult to be divided and it is difficult for the portable device to be inside or outside the vehicle interior. It will not be possible to determine precisely if it exists.

  In the case where the position of the portable device is determined based on the RSSI of the request signal as in the technique disclosed in Patent Document 2, the distance measurement accuracy deteriorates as the distance from the antenna transmitting the request signal increases. In the vicinity of the indoor / outdoor boundary, it is difficult to accurately determine whether the portable device exists inside or outside of the vehicle interior.

  One object of the present disclosure is to more accurately determine whether a portable device exists inside or outside of a vehicle interior when determining the position of the portable device, even when the body of the vehicle is resinified. It is an object of the present invention to provide a vehicle system, an on-vehicle device, and a portable device that make it possible.

  The above object is achieved by a combination of the features of the independent claims, and the subclaims define further advantageous embodiments of the disclosure. The reference numerals in parentheses described in the claims indicate the correspondence with specific means described in the embodiments described later as one aspect, and do not limit the technical scope of the present disclosure. .

  In order to achieve the above object, the first vehicle system is to be carried by a user and receive a signal transmitted on radio waves from transmission antennas (31, 31a, 31b, 31c) disposed in the vehicle. The portable device (2) includes a reply unit (23) that returns a response signal to the original, and the in-vehicle device (30) includes a position determination unit (306) that is used in a vehicle and determines the position of the portable device. In the vehicle system, the transmission antenna is disposed in the boundary area of the vehicle interior and outside of the vehicle such that the direction of the magnetic field vector is different at the boundary area, and the portable device receives from the transmission antenna A measurement unit (220) for measuring the received signal strength of the signal, and a vector direction identification unit (201 for specifying the direction of the magnetic field vector of the transmission antenna based on the radio wave transmitted by placing the signal from the transmission antenna) The reply unit sends back a response signal including the received signal strength measured by the measurement unit and the direction of the magnetic field vector identified by the vector direction identification unit, and the in-vehicle device obtains the response signal sent back from the reply unit. The position determination unit uses the direction of the magnetic field vector in addition to the received signal strength included in the response signal acquired by the acquisition unit, and the portable device is positioned anywhere inside or outside the vehicle compartment of the vehicle. The position of the portable device is determined by performing internal / external determination of

  Further, in order to achieve the above object, the first on-vehicle apparatus is used in a vehicle, carried by a user, and transmitted on radio waves from transmission antennas (31, 31a, 31b, 31c) disposed in the vehicle. The position determination unit (306) that determines the position of the portable unit to which the response signal is to be sent based on the reception of the input signal, and the transmission antenna is a boundary region outside the vehicle interior of the vehicle. The direction of the magnetic field vector is arranged so that the direction of the magnetic field vector is different at the boundary region, and the received signal strength of the signal received from the transmitting antenna measured by the portable device and the signal from the transmitting antenna returned from the portable device And an acquisition unit (303) for acquiring a response signal including the direction of the magnetic field vector of the transmission antenna specified by the portable device based on radio waves transmitted, and the position determination unit is acquired by the acquisition unit The In addition to the received signal strength is included in the response signal, it determines the position of the portable device by doing the outside judgment portable device with the direction of the magnetic field vector is located either outside the passenger compartment of the vehicle.

  According to these, since the received signal strength of the signal received from the transmitting antenna measured by the portable device is attenuated as the distance to the transmitting antenna increases, it is possible to use the received signal strength for the portable device for the vehicle. It is possible to determine the rough position of the aircraft. Also, since the transmitting antenna is arranged in the boundary area of the vehicle interior and outside of the vehicle so that the direction of the magnetic field vector is different at the boundary area, the portable device is located near this boundary area from the received signal strength. Even in the case where it is only possible to determine, even if the direction of the magnetic field vector of the transmitting antenna is used, it is possible to more accurately determine which one is outside the vehicle interior. This holds true even when the body of the vehicle is resinified and the radio waves are transmitted without being blocked by the body. On the other hand, in addition to the reception signal strength included in the response signal acquired by the acquisition unit, the position determination unit determines inside / outside of the vehicle interior of the vehicle by using the direction of the magnetic field vector. Go and determine the position of the portable device. Therefore, according to the above configuration, even if the body of the vehicle is resinified, it is possible to more accurately determine whether the portable device is outside the vehicle or inside the vehicle.

  Also, in order to achieve the above object, the first portable device is carried by the user and receives a signal transmitted on radio waves from transmission antennas (31, 31a, 31b, 31c) disposed in the vehicle It is a portable machine provided with the reply part (23) which returns a reply signal based on a thing, and it is arranged so that the direction of a magnetic field vector may be different bordering on the border area in the border area of the vehicle interior and outside of a vehicle. From a measuring unit (220) for measuring the received signal strength of a signal received from a transmitting antenna, and from the transmitting antenna arranged in the boundary region of the vehicle interior and outside of the vehicle so that the direction of the magnetic field vector is different at the boundary region. And a vector direction specifying unit (201) for specifying the direction of the magnetic field vector of the transmitting antenna based on the radio wave transmitted by mounting the signal, and the reply unit measures the received signal strength and vector measured by the measuring unit. It returns a response signal including the direction of the magnetic field vector identifying countercurrently specifying unit.

  According to this, since the reception signal strength of the signal received from the transmission antenna measured by the measurement unit is attenuated as the distance to the transmission antenna is increased, it is possible to use the received signal strength to carry the mobile phone for the vehicle. It is possible to determine the rough position of the aircraft. Also, since the transmitting antenna is arranged in the boundary area of the vehicle interior and outside of the vehicle so that the direction of the magnetic field vector is different at the boundary area, the portable device is located near this boundary area from the received signal strength. Even in the case where it is only possible to determine, even if the direction of the magnetic field vector of the transmitting antenna is used, it is possible to more accurately determine which one is outside the vehicle interior. This holds true even when the body of the vehicle is resinified and the radio waves are transmitted without being blocked by the body. On the other hand, since the reply unit sends back a response signal including the direction of the magnetic field vector in addition to the received signal strength, the device for acquiring this response signal is portable even if the body of the vehicle is resinified. This makes it possible to more accurately determine whether the aircraft is outside the vehicle compartment or in the vehicle compartment.

  Further, in order to achieve the above object, the second vehicle system is carried by the user, and a plurality of transmission antennas (31, 31a, 31b, 31c) arranged in the vehicle transmit signals in order on radio waves. The portable device (2a) includes a reply unit (23a) that sends a response signal to each transmitting antenna based on the reception of the signal, and a position determination unit (306a) that is used in a vehicle and determines the position of the portable device. A vehicle system including an on-vehicle device (30a), wherein the transmitting antenna is disposed in a boundary region of the vehicle interior and outside of the vehicle such that the direction of the magnetic field vector is different at the boundary region. The device includes a vector direction identification unit (201) that identifies the direction of the magnetic field vector of the transmission antenna based on radio waves transmitted by transmitting signals from the transmission antenna, and the reply unit The response signal including the direction of the magnetic field vector specified by the constant unit is returned, and the in-vehicle apparatus includes an acquisition unit (303a) for acquiring the response signal returned from the reply unit, and the position determination unit acquires it by the acquisition unit. Based on the combination of the directions of the magnetic field vectors respectively contained in the response signals of the transmitting antennas, it is judged inside or outside of the vehicle interior of the vehicle whether the portable device is located inside or outside.

  Further, in order to achieve the above object, the second on-vehicle apparatus is used in a vehicle, carried by a user, and placed on a radio wave in order from a plurality of transmission antennas (31, 31a, 31b, 31c) arranged in the vehicle. An on-vehicle apparatus including a position determination unit (306a) that determines the position of the portable device that sends back a response signal for each transmission antenna based on the reception of the signal to be transmitted. In the outer boundary area, the direction of the magnetic field vector is arranged so that the direction of the magnetic field is different at the boundary area, and the portable terminal sends the signal based on the radio wave transmitted from the transmitting antenna. Device includes an acquisition unit (303a) for acquiring a response signal including the direction of the magnetic field vector of the transmission antenna specified by the device, and the position determination unit determines the response signal for each transmission antenna acquired by the acquisition unit. Murrell field vector portable device from the combination of the direction of performing or outside judgment located either outside the passenger compartment of the vehicle.

  According to these, the plurality of transmitting antennas are arranged in the boundary area of the vehicle interior and outside of the vehicle such that the direction of the magnetic field vector is different at the boundary area, and the portable device is located near this boundary area. Even in this case, the combination of the directions of the magnetic field vectors of the plurality of transmitting antennas differs depending on where the portable device is located inside or outside the vehicle cabin. Therefore, it is possible to more accurately determine which one is inside or outside the vehicle compartment from the combination of the directions of the magnetic field vectors of the plurality of transmitting antennas. This holds true even when the body of the vehicle is resinified and the radio waves are transmitted without being blocked by the body. On the other hand, the position determination unit determines inside and outside of the vehicle interior of the vehicle from inside and outside of the vehicle from the combination of the directions of the magnetic field vectors included in the response signals for each transmission antenna acquired by the acquisition unit. To determine the position of the portable device. Therefore, according to the above configuration, even if the body of the vehicle is resinified, it is possible to more accurately determine whether the portable device is outside the vehicle or inside the vehicle.

  In addition, in order to achieve the above object, the second portable device is carried by the user, and a signal transmitted on radio waves in order from transmission antennas (31, 31a, 31b, 31c) arranged in a plurality of vehicles. The portable device includes a reply unit (23a) that sends a response signal to each transmitting antenna based on the reception of the signal, and the direction of the magnetic field vector is bordered on the border area inside the vehicle interior and outside of the vehicle. And a vector direction identification unit (201) for identifying the direction of the magnetic field vector of the transmission antenna based on radio waves transmitted by transmitting antennas from different transmission antennas. A response signal including the direction of the magnetic field vector specified by the part is returned.

  According to this, since the plurality of transmitting antennas are arranged in the boundary area of the vehicle interior and outside of the vehicle so that the direction of the magnetic field vector is different at the boundary area, the measuring unit of the portable device is near this boundary area. The combination of the directions of the magnetic field vectors of the plurality of transmitting antennas differs depending on whether the portable device is located inside or outside the vehicle cabin, even in the case of Therefore, it is possible to more accurately determine which one is inside or outside the vehicle compartment from the combination of the directions of the magnetic field vectors of the plurality of transmitting antennas. This holds true even when the body of the vehicle is resinified and the radio waves are transmitted without being blocked by the body. On the other hand, since the reply unit sends back a response signal for each transmission antenna including the direction of the magnetic field vector, the portable device can obtain the response signal even if the vehicle body is resinified. This makes it possible to more accurately determine whether the vehicle is outside the vehicle or inside the vehicle.

1 shows an example of a schematic configuration of a vehicle system 1. FIG. FIG. 2 is a view showing an example of a schematic configuration of a portable device 2; FIG. 7 is a schematic diagram for explaining how to determine the direction of the magnetic field vector of the LF transmission antenna 31. FIG. 2 is a view showing an example of a schematic configuration of a vehicle side unit 3; FIG. 7 is a schematic view for explaining an example of the arrangement of the LF transmission antenna 31. It is a figure which shows an example of a rough structure of BCM30. FIG. 18 is a schematic diagram for describing an example of inside / outside determination using a combination of directions of magnetic field vectors of different LF transmitting antennas 31. It is a flowchart which shows an example of the flow of a position determination related process of the portable device 2 in BCM30. It is a figure which shows an example of a rough structure of the portable device 2a. It is a figure which shows an example of a rough structure of BCM30a.

  DETAILED DESCRIPTION Embodiments of the disclosure will be described with reference to the drawings. Note that, for convenience of explanation, among the plurality of embodiments, portions having the same functions as the portions shown in the figures used in the description so far are given the same reference numerals and may not be described. is there. The description in the other embodiments can be referred to for parts denoted by the same reference numerals.

(Embodiment 1)
<Schematic Configuration of Vehicle System 1>
As shown in FIG. 1, a vehicle system 1 includes a portable device 2 carried by a user and a vehicle unit 3 used in the vehicle. Note that "to be carried by the user" is not limited to being carried by the user, but also includes a state such as being left behind that is not carried by the user.

  Each of the portable device 2 and the vehicle unit 3 can transmit and receive signals by radio communication on radio waves. When the portable device 2 and the vehicle unit 3 are within the communication range of each other, the other receives the signal transmitted by one by wireless communication. In the present embodiment, the vehicle system 1 performs authentication between the portable device 2 and the vehicle-side unit 3 by verification through wireless communication, and when authentication is established, control of the vehicle as an authentication target is possible. The description will be made by taking as an example the case of having the function to be performed. Examples of vehicle control that can be performed by authentication include locking and unlocking of a door, starting of a traveling drive source, and the like.

<Schematic Configuration of Portable Device 2>
Next, the portable device 2 will be described using FIG. As shown in FIG. 2, the portable device 2 includes a control device 20, an LF reception antenna 21, an LF reception unit 22, an RF transmission unit 23, and an RF transmission antenna 24.

  The LF receiving antenna 21 receives a signal (hereinafter referred to as an LF signal) transmitted from an LF transmitting antenna 31 described later on radio waves of the LF band. The LF band is, for example, a low frequency band of 30 kHz to 300 kHz. Examples of the LF signal received by the portable device 2 include a challenge signal requesting transmission of a code for collation, and a burst signal for measuring a received signal strength (hereinafter referred to as RSSI). The challenge signal is a signal for encrypted communication and is a signal of a code composed of random numbers. The following description will be made on the assumption that the LF reception antenna 21 is a magnetic field type antenna and, as an example, is a biaxial coil antenna disposed so as to be orthogonal to each other. Hereinafter, these two axes will be referred to as an X axis and a Y axis for the sake of convenience.

  The LF reception unit 22 generates a reception signal while electrically processing the LF signal received by the LF reception antenna 21, and outputs the generated reception signal to the control device 20. Further, the LF reception unit 22 includes an RSSI measurement circuit 220 and a current detection unit 221. The RSSI measurement circuit 220 is a circuit that measures the RSSI, measures the RSSI of the burst signal received by the LF reception antenna 21, and outputs the measured RSSI to the control device 20. The RSSI measurement circuit 220 corresponds to a measurement unit. The current detection unit 221 detects the current flowing in each of the X axis and Y axis biaxial coil antennas of the LF reception antenna 21, and outputs detection results such as the amount of current and the direction of current to the control device 20.

  While electrically processing the original signal input from the control device 20, the RF transmission unit 23 generates a response signal to the LF signal received by the LF reception antenna 21, and transmits this response signal from the RF transmission antenna 24. . The RF transmission unit 23 corresponds to a reply unit. The RF transmission antenna 24 transmits a response signal on radio waves in an RF (Radio Frequency) band. The RF band is, for example, a high frequency band of 300 Hz to 3 THz.

  The control device 20 is an IC, a microcomputer, or the like, and when the reception signal of the challenge signal is input from the LF reception unit 22, the control device 20 encrypts the code of the challenge signal using a secret key and an encryption algorithm using common key encryption. Generate encrypted encryption code.

  Further, the control device 20 has a vector direction identification unit 201, and the vector direction identification unit 201 transmits this LF signal from the detection result detected by the current detection unit 221 when the LF reception antenna 21 receives the LF signal. The direction of the magnetic field vector of the original LF transmission antenna 31 is specified. As an example, the direction of the magnetic field vector of the LF transmission antenna 31 that is the transmission source of the burst signal may be specified from the detection result detected by the current detection unit 221 when the burst signal is received. The direction of the magnetic field vector is, as shown in FIG. 3, an X-axis magnetic field Hx specified from the current amount and current direction of the X-axis coil antenna of the LF receiving antenna 21 and the Y-axis coil antenna of the LF receiving antenna 21 The magnetic field Hy of the Y axis specified from the current amount and the current direction is combined to obtain the magnetic field vector H.

  Then, the control device 20 generates an original signal of the response signal including the RSSI of the burst signal measured by the RSSI measuring circuit 220 and the direction of the magnetic field vector specified by the vector direction specifying unit 201, and this original signal is transmitted to the RF transmitting unit 23 Output to As a result, the RF transmission unit 23 transmits a response signal including the RSSI and the direction of the magnetic field vector. When a burst signal is received by the LF receiving antenna 21 following the challenge signal from the same LF transmitting antenna 31, the above-described encrypted code is also included in the response signal and sent back. Also, when LF signals are transmitted in order from a plurality of LF transmission antennas 31, a response signal is returned for each timing at which the LF signal is transmitted, so that a response signal is returned for each LF transmission antenna 31. Become.

<Schematic Configuration of Vehicle Side Unit 3>
Subsequently, a schematic configuration of the vehicle unit 3 will be described with reference to FIG. As shown in FIG. 4, the vehicle side unit 3 includes a BCM (Body Control Module) 30, LF transmission antennas 31 a to 31 c, and an RF receiver 32.

  The LF transmission antennas 31 a to 31 c are transmission antennas that transmit signals using radio waves in the LF band. When the description is made without distinguishing the LF transmission antennas 31a to 31c, the LF transmission antennas 31 are hereinafter referred to as the LF transmission antenna 31. The LF transmission antenna 31 is a magnetic field type antenna using an antenna coil, and is an example of a bar antenna of one axis. Further, as shown in FIG. 5, the LF transmitting antenna 31 is disposed in the boundary area of the vehicle interior and outside of the vehicle so that the direction of the magnetic field vector is different at the boundary area. Arrows in FIG. 5 indicate the directions of magnetic field vectors when the vehicle is viewed from the ceiling direction. The boundary area outside the vehicle interior of the vehicle may be, for example, an area corresponding to the body of the vehicle. The body referred to here includes the door of the vehicle. Further, in the present embodiment, the body is resinified. The resinification of the body is not limited to the case where all the body is resinified, but also includes the case where the body is largely resinified, such as at least a majority of the boundary area where the LF transmission antenna 31 is disposed. It shall be

  The LF transmission antenna 31a is disposed on the right side of the vehicle of the vehicle. As an example, the case where the axis is built into the outer door handle of the driver's seat of the vehicle (that is, the D seat) so as to be along the longitudinal direction of the vehicle will be described below as an example. The LF transmission antenna 31 b is disposed on the left side of the vehicle of the vehicle. As an example, the case where the axis is built in along the longitudinal direction of the vehicle will be described below as an example in the outer door handle of the front passenger seat (that is, P seat) of the vehicle. The following description will be made on the assumption that the LF transmission antenna 31a and the LF transmission antenna 31b are respectively disposed in the same direction on the left and right of the vehicle. The same direction in this case means that the direction of the current flowing through the antenna coil is the same in addition to the direction of the axis of the antenna coil. The LF transmission antenna 31c is disposed on the rear side of the vehicle of the vehicle. As an example, in the following, a description will be given by taking as an example a case where the axis is built in the left and right direction of the vehicle in the rear bumper.

  The RF receiver 32 receives a response signal transmitted from the portable device 2 side in an RF band radio wave. The BCM 30 includes a processor, a memory, an I / O, and a bus connecting these, and executes various processes related to authentication in the vehicle by executing a control program stored in the memory. As used herein, memory is a non-transitory tangible storage medium that non-temporarily stores computer readable programs and data. In addition, the non-transitional tangible storage medium is realized by a semiconductor memory or a magnetic disk. The BCM 30 corresponds to an in-vehicle device.

<Schematic Configuration of BCM 30>
Next, an example of a schematic configuration of the BCM 30 will be described with reference to FIG. As shown in FIG. 6, the BCM 30 includes a microcomputer 300 and an LF driver IC 310. The BCM 30 is connected to an actuator such as a door lock motor, another electronic control unit such as a power unit ECU that controls a traveling drive source of a vehicle, an RF receiver 32, and the like.

  As shown in FIG. 6, the microcomputer 300 sets the vehicle state determination unit 301, the request unit 302, the response acquisition unit 303, the storage unit 304, the check unit 305, the position determination unit 306, and the vehicle control permission unit 307 as functional blocks. Prepare.

  The vehicle state determination unit 301 determines the state of the vehicle based on the sensing result on the vehicle state. For example, based on the vehicle speed detected by the vehicle speed sensor, the shift position detected by the shift position sensor, the signal of the parking brake switch, etc., it is determined whether the vehicle is parked or not.

  The request unit 302 sends a challenge signal to the LF driver IC 310 in a predetermined situation according to a signal input from a switch (hereinafter, SW) related to authentication in the BCM 30 and a vehicle state determined by the vehicle state determination unit 301. It requests the transmission of the subsequent burst signal. As switches related to authentication with the BCM 30, there are a push SW for requesting start of a traveling drive source of a vehicle, a door handle SW provided on an outer door handle of a vehicle door, a rear bumper SW provided on a rear bumper of a vehicle, etc. There is.

  As an example of the above-mentioned predetermined | prescribed situation, vehicle exterior collation and vehicle interior collation are mentioned. The vehicle exterior verification is performed when the vehicle state determination unit 301 determines that the vehicle is parked, and a signal indicating that the door handle SW or the rear bumper SW is operated is input. In the exterior checkup, the request unit 302 requests the LF driver IC 310 to transmit LF signals in order from the LF transmission antennas 31a to 31c. Further, the vehicle interior verification is performed when the vehicle state determination unit 301 determines that the own vehicle is parked, and a signal indicating that the push SW has been operated is input. The request unit 302 also requests the LF driver IC 310 to transmit LF signals in order from the LF transmission antennas 31 a to 31 c in the interior verification.

  As an example, during out-of-vehicle verification and in-room verification, after a challenge signal is transmitted from one of the LF transmission antennas 31a to 31c, a burst signal is transmitted, and a challenge is transmitted from the remaining LF transmission antennas 31. The configuration may be such that the burst signal is transmitted without transmitting the signal. The challenge signal and the burst signal may be transmitted from any of the LF transmission antennas 31a to 31c.

  The LF driver IC 310 is an IC that transmits an LF signal from the LF transmission antennas 31 a to 31 c. The LF driver IC 310 causes the LF transmission antennas 31 a to 31 c to transmit the LF signal in order according to the request from the request unit 302.

  The portable device 2 sends back a response signal for each LF transmission antenna 31 to the LF signals to be transmitted in order from the LF transmission antennas 31a to 31c. Further, in the BCM 30, the response signal for each LF transmission antenna 31 is distinguished according to which of the LF transmission antennas 31a to 31c the response signal corresponds to the transmission timing of the LF transmission antenna 31.

  The response acquisition unit 303 acquires a response signal received from the portable device 2 by the RF receiver 32. When the response signal contains an encrypted code, the response acquiring unit 303 outputs the encrypted code to the collating unit 305. Further, the response acquisition unit 303 outputs the RSSI and the direction of the magnetic field vector for each LF transmission antenna 31 included in the response signal to the position determination unit 306.

  The storage unit 304 stores, for example, a secret key used in the common key cryptosystem as information for authentication. The collation unit 305 is obtained by encrypting the encryption code included in the response signal acquired by the response acquisition unit 303 and the code of the challenge signal transmitted from the LF transmission antenna 31 with the secret key stored in the storage unit 304. Check against the encryption code.

  The position determination unit 306 uses the combination of the direction of the magnetic field vector for each of the LF transmission antennas 31 acquired by the response acquisition unit 303 in addition to the RSSI for each of the LF transmission antennas 31 acquired by the response acquisition unit 303. Determine

  The position determination unit 306 estimates a rough position of the portable device 2 from the RSSI of each LF transmission antenna 31 acquired by the response acquisition unit 303. Since the RSSI attenuates as the distance between the LF transmission antenna 31 and the portable device 2 increases, as an example, the LF transmission antennas 31a to 31c are similar to those disclosed in Patent Document 2. The distance from each LF transmission antenna 31 to the portable device 2 is calculated from the RSSI of each of the three LF transmission antennas 31. Then, based on the calculated distance and the arrangement position of each LF transmission antenna 31 in the vehicle, the position of the portable device 2 is estimated by the principle of triangulation.

  When the position of the portable device 2 is estimated based on the RSSI of the LF signal, the distance measurement accuracy deteriorates as the distance from the LF transmission antenna 31 increases. Therefore, as described above, the portable device 2 is Even in the case of estimating the position, it is difficult to accurately determine whether the portable device 2 is located inside or outside the vehicle compartment of the vehicle.

  Therefore, the position determination unit 306 determines inside / outside of the interior of the vehicle interior of the vehicle from the combination of the direction of the magnetic field vector of each LF transmission antenna 31 in addition to the position estimated from the RSSI . Here, an example of the inside / outside determination based on the combination of the directions of the magnetic field vectors of the LF transmission antennas 31 will be described with reference to FIG. 7. In FIG. 7, the case where the portable device 2 is estimated to be closest to the LF transmission antenna 31 a among the LF transmission antennas 31 a to 31 c from the RSSI will be described as an example. The solid line arrow in FIG. 7 indicates the direction of the magnetic field vector of the LF transmission antenna 31a when the vehicle is viewed from the ceiling direction, and the dashed arrow indicates the LF transmission antenna 31b when the vehicle is viewed from the ceiling direction The direction of the magnetic field vector is shown. Further, FIG. 7 shows the portable device 2 when In is located in the vehicle compartment, and shows the portable device 2 when Out is located outside the vehicle.

  In the present embodiment, the LF transmission antenna 31a and the LF transmission antenna 31b are disposed on the left and right of the vehicle in the same direction, respectively, and the magnetic field is separated from the boundary area in the boundary area outside the vehicle interior of the vehicle. The directions of the vectors are arranged differently. Therefore, when the portable device 2 is closer to the LF transmission antennas 31a and 31b than the LF transmission antenna 31c, the LF transmission antenna 31a and the LF transmission antenna 31b are determined depending on where the portable device 2 is located inside or outside the vehicle. The combination of the directions of the magnetic field vectors of is determined more precisely. For example, when the portable device 2 is located in the vehicle compartment, as shown in FIG. 7, the direction of the magnetic field vector of the LF transmission antenna 31a and the direction of the magnetic field vector of the LF transmission antenna 31b become opposite. On the other hand, when the portable device 2 is located outside the vehicle, as shown in FIG. 7, the direction of the magnetic field vector of the LF transmission antenna 31a and the direction of the magnetic field vector of the LF transmission antenna 31b have the same tendency. As described above, the inside / outside determination can be performed with high accuracy from the combination of the directions of the magnetic field vectors of the LF transmission antennas 31 according to where the portable device 2 is located inside or outside the vehicle interior. Therefore, the position determination unit 306 determines inside / outside of the vehicle interior whether the portable device 2 is positioned by performing inside / outside determination from the combination of the direction of the magnetic field vector of each LF transmission antenna 31 in addition to the position estimated from RSSI. It judges more accurately.

  Here, although the case where LF transmission antenna 31a and LF transmission antenna 31b were arrange | positioned by the same direction on the left and right of a vehicle respectively was mentioned as the example, it does not necessarily restrict to this. When the LF transmission antenna 31a and the LF transmission antenna 31b are disposed on the left and the right of the vehicle in opposite directions, the tendency according to the combination of the direction of the magnetic field vector is the reverse. Specifically, when the portable device 2 is located in the vehicle compartment, the direction of the magnetic field vector of the LF transmitting antenna 31a and the direction of the magnetic field vector of the LF transmitting antenna 31b have the same tendency, while the portable device 2 is located outside the vehicle In this case, the direction of the magnetic field vector of the LF transmission antenna 31a and the direction of the magnetic field vector of the LF transmission antenna 31b have an opposite tendency.

  As described above, the combination of the directions of the LF transmission antenna 31a and the LF transmission antenna 31b determines the tendency according to the combination of the directions of the magnetic field vectors according to the inside and the outside of the vehicle compartment. Therefore, the position determination unit 306 performs the LF transmission described in the above-described example by making the tendency according to the combination of the directions of the magnetic field vectors according to the combination of the directions of the respective LF transmission antennas 31 according to the inside and the outside of the vehicle interior. The configuration is not limited to the combination of the directions of the antenna 31 and the LF transmission antenna 31, and the inside / outside determination may be performed based on the combination of the directions of the magnetic field vectors. For example, the combination of the LF transmission antenna 31a and the LF transmission antenna 31c, the combination of the LF transmission antenna 31b and the LF transmission antenna 31c, and the combination of the LF transmission antennas 31a to 31c can also be used for inside / outside determination.

  Moreover, although the structure which estimates the position of the portable device 2 by the principle of triangulation from the RSSI for every LF transmission antenna 31 was shown here, it does not necessarily restrict to this. For example, the area where the portable device 2 is located may be roughly narrowed down and estimated depending on whether the RSSI of each LF transmission antenna 31 is equal to or more than a threshold.

  The vehicle control permission unit 307 locks and unlocks the door of the vehicle when, for example, the collation by the collating unit 305 is established at the time of collaborating outside the vehicle and the position judging unit 306 judges that the portable device 2 is located outside the vehicle. A drive signal for control is output to the door lock motor to lock and unlock the door of the vehicle. Further, for example, when the vehicle control permission unit 307 determines that the matching unit 305 matches at the time of vehicle interior matching, and the position determination unit 306 determines that the portable device 2 is positioned in the vehicle interior, Output to the ECU to start the traveling drive source of the vehicle. If it is determined by the position determination unit 306 that the portable device 2 is located outside the vehicle compartment, the traveling drive source of the vehicle may not be started. According to this, by using a repeater, the third party can far away the challenge signal transmitted from the LF transmission antenna 31, and indirectly realize the wireless communication between the BCM 30 and the portable device 2, thereby performing code collation. It is possible to prevent taking out of the vehicle due to the relay attack that is established illegally.

  In the present embodiment, the configuration in which the determination result of the position determination unit 306 is used to permit the control of the vehicle is shown as an example, but the present invention is not necessarily limited thereto. For example, the determination result of the position determination unit 306 may be used for another application such as detecting the confinement of the portable device 2 in the vehicle compartment when the occupant gets off the vehicle and outputting a warning.

<Position determination related processing in BCM 30>
Subsequently, processing related to the determination of the position of the portable device 2 in the BCM 30 (hereinafter, position determination related processing) will be described using the flowchart in FIG. 8. The flowchart of FIG. 8 may be started when the request unit 302 of the BCM 30 requests the LF driver IC 310 to transmit a challenge signal and a subsequent burst signal in a predetermined situation.

  First, in step S1, the LF driver IC 310 causes the LF transmission antennas 31 to transmit LF signals in order. As an example, as described above, the burst signal is transmitted after the challenge signal is transmitted from one of the LF transmission antennas 31a to 31c, and the challenge signal is transmitted from the remaining LF transmission antennas 31. Instead, it may be configured to transmit a burst signal.

  In step S 2, the response acquisition unit 303 acquires the directions of the RSSI and the magnetic field vector included in the response signal sequentially received by the RF receiver 32 with respect to the transmission of the LF signal from each LF transmission antenna 31. In step S3, the position determination unit 306 estimates the position of the portable device 2 from the RSSI of each LF transmission antenna 31 included in the response signal acquired in S2. In step S4, in addition to the position of the portable device estimated in step S3, the position determination unit 306 detects the direction of the magnetic field vector of the LF transmission antenna 31 included in the response signal acquired in step S2. Inside or outside of the outside is determined to determine the position of the portable device 2, and the position determination related process is ended.

<Summary of Embodiment 1>
The RSSI of the signal received from the LF transmission antenna 31, which is measured by the portable device 2, attenuates as the distance to the LF transmission antenna 31 increases. It is possible to determine the rough position. Further, since the LF transmission antenna 31 is arranged in the boundary area of the vehicle interior and outside of the vehicle so that the direction of the magnetic field vector is different at the boundary area, the portable device 2 is located near this boundary area from RSSI. Even in the case where it is only possible to determine, the use of the direction of the magnetic field vector of the LF transmission antenna 31 makes it possible to more accurately determine which one is inside or outside the vehicle compartment. This holds true even when the body of the vehicle is resinified and the radio waves are transmitted without being blocked by the body. On the other hand, according to the configuration of the first embodiment, in addition to the RSSI included in the response signal acquired by the response acquisition unit 303, the position determination unit 306 performs the inside / outside determination using the direction of the magnetic field vector. Determine the position of Therefore, even if the body of the vehicle is resinified and the radio waves are transmitted without being shielded by the body, it is possible to use the direction of the magnetic field vector to determine where the portable device 2 is located inside or outside the vehicle interior It becomes possible to judge accurately.

Second Embodiment
In the first embodiment, the configuration for determining the position of the portable device 2 from the combination of the directions of the RSSI and the magnetic field vector for each of the plurality of LF transmission antennas 31 has been described, but the present invention is not necessarily limited thereto. For example, the position of the portable device 2 may be determined from the RSSI of one LF transmission antenna 31 and the direction of the magnetic field vector.

  As an example, in the case where the position of the portable device 2 is determined only in the vicinity of the D seat of the vehicle, the condition that the RSSI of the burst signal transmitted from the LF transmission antenna 31a is equal to or more than the threshold value Thus, it is possible to accurately determine in which position the portable device 2 is located inside or outside the vehicle cabin near the D seat according to the direction of the magnetic field vector of the LF transmission antenna 31a.

(Embodiment 3)
In the first embodiment, although the case where the three LF transmission antennas 31 of the LF transmission antennas 31a to 31c are used is described as an example, the present invention is not necessarily limited thereto, and the number of LF transmission antennas 31 other than three is used. It is good also as composition. For example, two LF transmission antennas 31 may be used on the left and right of the vehicle, or four LF transmission antennas 31 may be used on the left and right of the vehicle. In addition, a configuration may be used in which five LF transmission antennas 31 are used, two each on the left and right of the vehicle and one at the rear of the vehicle.

(Embodiment 4)
Although the above-mentioned embodiment showed a composition which uses RSSI about a burst signal transmitted from LF transmitting antenna 31 for judgment of a position of portable machine 2, it does not necessarily restrict to this. For example, the RSSI may not be used to determine the position of the portable device 2 (hereinafter, the fourth embodiment). The configuration of the fourth embodiment will be described below. The vehicle system 1 of the fourth embodiment includes a portable device 2a carried by a user and a vehicle side unit 3a used in a vehicle. The portable device 2a is the same as the portable device 2 of the first embodiment except that some processes are different. The vehicle side unit 3a is the same as the vehicle side unit 3 of the first embodiment except that the BCM 30a is included instead of the BCM 30.

  First, the portable device 2a will be described using FIG. As shown in FIG. 9, the portable device 2a includes a control device 20a, an LF reception antenna 21, an LF reception unit 22a, an RF transmission unit 23a, and an RF transmission antenna 24. The portable device 2a includes the control device 20a, the LF reception unit 22a, and the RF transmission unit 23a instead of the control device 20, the LF reception unit 22, and the RF transmission unit 23, and the portable device according to the first embodiment. It is the same as machine 2.

  The LF receiver 22a has a current detector 221 as shown in FIG. The LF reception unit 22 a is the same as the LF reception unit 22 of the first embodiment except that the RSSI measurement circuit 220 is not provided. The control device 20a includes the vector direction identification unit 201, generates an original signal of a response signal including the direction of the magnetic field vector identified by the vector direction identification unit 201, and outputs the original signal to the RF transmission unit 23a. The control device 20a is the same as the control device 20 of the first embodiment except that the control device 20a generates an original signal of the response signal not including the RSSI. The RF transmission unit 23 a transmits a response signal including the direction of the magnetic field vector from the RF transmission antenna 24 separately for the LF transmission antenna 31. The RF transmission unit 23a is the same as the RF transmission unit 23 of the first embodiment except that the response signal does not include the RSSI.

  Subsequently, the BCM 30a will be described with reference to FIG. As shown in FIG. 10, the BCM 30a includes a microcomputer 300a and an LF driver IC 310. The BCM 30a is the same as the BCM 30 of the first embodiment except that the BCM 30a includes a microcomputer 300a instead of the microcomputer 300. Further, as shown in FIG. 10, the microcomputer 300a functions as the vehicle state determination unit 301, the request unit 302, the response acquisition unit 303a, the storage unit 304, the check unit 305, the position determination unit 306a, and the vehicle control permission unit 307. Prepare as a block. The microcomputer 300 a is the same as the microcomputer 300 of the first embodiment except that the microcomputer 300 a includes a response acquisition unit 303 a and a position determination unit 306 a instead of the response acquisition unit 303 and the position determination unit 306.

  The response acquisition unit 303 a acquires a response signal received from the portable device 2 by the RF receiver 32. Further, the response acquisition unit 303a outputs the direction of the magnetic field vector of each LF transmission antenna 31 included in the response signal to the position determination unit 306a. The response acquisition unit 303 a is the same as the response acquisition unit 303 of the first embodiment except that the RSSI for each LF transmission antenna 31 is not acquired.

  The position determination unit 306 a determines inside and outside of the vehicle interior of the vehicle from inside and outside of the vehicle from the combination of the directions of the magnetic field vectors of the LF transmission antennas 31. When the LF transmitting antenna 31 is arranged in the boundary area of the vehicle inside and outside of the vehicle such that the direction of the magnetic field vector is different at the boundary area, the magnetic field vector seen outside the vehicle but not seen in the vehicle Direction exists. Therefore, when the combination of the directions of the magnetic field vectors of the plurality of LF transmission antennas 31 includes at least one direction of the magnetic field vector which can be seen outside the vehicle but not the vehicle interior, the portable device 2 is It determines that it is located outdoors. On the other hand, when the direction of the magnetic field vector which can be seen outside the vehicle but not in the vehicle is not included, it is determined that the portable device 2 is located in the vehicle. In order to further increase the accuracy of the inside / outside determination by the position determination unit 306 a, it is preferable that the plurality of LF transmission antennas 31 be arranged to surround the vehicle room, such as the left and right of the vehicle, the left and right and the rear of the vehicle.

  As described above, even with the configuration of the fourth embodiment, it is possible to more accurately determine whether the portable device 2 is located inside or outside of the vehicle compartment from the combination of the directions of the magnetic field vectors of the plurality of LF transmission antennas 31. become.

  In the fourth embodiment, the configuration may be such that the number of LF transmission antennas 31 other than three is used. For example, two LF transmission antennas 31 may be used on the left and right of the vehicle, or four LF transmission antennas 31 may be used on the left and right of the vehicle. In addition, a configuration may be used in which five LF transmission antennas 31 are used, two each on the left and right of the vehicle and one at the rear of the vehicle.

  The present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in the different embodiments. Is also included in the technical scope of the present disclosure.

Reference Signs List 1 vehicle system, 2, 2a portable device, 3, 3a vehicle side unit, 20 control device, 21 LF receiving antenna, 22 LF receiving unit, 23, 23a RF transmitting unit (reply unit), 24 RF transmitting antenna, 30, 30c BCM (vehicle-mounted device), 31, 31a, 31b, 31c LF transmission antenna, 32 RF receiver, 201 vector direction identification unit, 220 RSSI measurement circuit, 221 current detection unit, 300 microcomputer, 303 response acquisition unit (acquisition unit), 306 Position determination unit, 310 LF driver IC

Claims (9)

A reply unit (23) for returning a response signal based on reception of a signal carried on radio waves from a transmitting antenna (31, 31a, 31b, 31c) carried by a user and disposed in a vehicle A portable device (2),
A vehicle system (30) including: a position determination unit (306) used in the vehicle and determining a position of the portable device;
The transmitting antenna is disposed in a boundary area of the vehicle inside and outside of the vehicle such that the direction of the magnetic field vector is different at the boundary area.
The portable device is
A measurement unit (220) for measuring the received signal strength of the signal received from the transmitting antenna;
And a vector direction specifying unit (201) for specifying the direction of the magnetic field vector of the transmitting antenna based on the radio wave transmitted by loading the signal from the transmitting antenna.
The reply unit sends back the response signal including the received signal strength measured by the measurement unit and the direction of the magnetic field vector identified by the vector direction identification unit.
The in-vehicle device is
An acquisition unit (303) for acquiring the response signal returned from the response unit;
The position determination unit may use the direction of the magnetic field vector, in addition to the received signal strength included in the response signal acquired by the acquisition unit, whether the portable device is located inside or outside the vehicle cabin of the vehicle A vehicle system that performs inside / outside determination to determine the position of the portable device. A plurality of the transmission antennas are disposed in the vehicle,
The reply unit replies the response signal for each of the transmission antennas based on reception of signals sequentially transmitted from the plurality of transmission antennas.
The position determination unit is a combination of the directions of the magnetic field vectors included in the response signals for each transmission antenna, in addition to the received signal strengths included in the response signals for each of the transmission antennas acquired by the acquisition unit. The vehicle system according to claim 1, wherein the position of the portable device is determined by performing the inside-outside determination from the inside. A response signal is sent back for each of the transmitting antennas based on the reception of the signals carried on the radio wave in order from the transmitting antennas (31, 31a, 31b, 31c) carried by the user and arranged in a plurality of vehicles. A portable unit (2a) comprising a reply unit (23a);
A vehicle system (30a) including a position determination unit (306a) used in the vehicle and determining the position of the portable device;
The transmitting antenna is disposed in a boundary area of the vehicle inside and outside of the vehicle such that the direction of the magnetic field vector is different at the boundary area.
The portable device is
And a vector direction identification unit (201) for identifying the direction of the magnetic field vector of the transmission antenna based on radio waves transmitted from the transmission antenna.
The reply unit replies the response signal including the direction of the magnetic field vector identified by the vector direction identifying unit;
The in-vehicle device is
An acquisition unit (303a) for acquiring the response signal returned from the response unit;
The position determination unit determines whether the portable device is located inside or outside of the vehicle interior of the vehicle based on a combination of directions of the magnetic field vectors included in the response signals for each of the transmission antennas acquired by the acquisition unit. Vehicle system that makes the determination. The transmitting antennas are respectively disposed at least in the same direction on the left and right of the vehicle,
The position determination unit is included in the direction of the magnetic field vector included in the response signal for the transmission antenna disposed on the left side of the vehicle, and in the response signal for the transmission antenna disposed on the right side of the vehicle When the direction of the magnetic field vector to be read is the same tendency, the inside / outside determination is performed when the portable device is located outside the vehicle exterior, while in the case of the opposite tendency, the portable device is in the vehicle interior of the vehicle The vehicle system according to claim 2 or 3, wherein the inside / outside determination is performed when located. The transmitting antennas are respectively disposed in opposite directions at least to the left and right of the vehicle,
The position determination unit is included in the direction of the magnetic field vector included in the response signal for the transmission antenna disposed on the left side of the vehicle, and in the response signal for the transmission antenna disposed on the right side of the vehicle If the direction of the magnetic field vector to be transmitted is in the opposite tendency, the inside / outside determination is performed if the portable device is located outside the vehicle exterior, while if the same tendency, the portable device is in the vehicle interior of the vehicle The vehicle system according to claim 2 or 3, wherein the inside / outside determination is performed when located. Used in vehicles,
Determine the position of the portable device that sends back the response signal based on the reception of the signal carried on the radio wave from the transmitting antenna (31, 31a, 31b, 31c) carried by the user and placed in the vehicle An on-vehicle apparatus including a position determination unit (306)
The transmitting antenna is disposed in a boundary area of the vehicle inside and outside of the vehicle such that the direction of the magnetic field vector is different at the boundary area.
Specified by the portable device based on the received signal strength of the signal received from the transmitting antenna measured by the portable device and returned from the portable device, and the radio wave transmitted with the signal from the transmitting antenna An acquisition unit (303) for acquiring the response signal including the direction of the magnetic field vector of the transmitting antenna;
The position determination unit may use the direction of the magnetic field vector, in addition to the received signal strength included in the response signal acquired by the acquisition unit, whether the portable device is located inside or outside the vehicle cabin of the vehicle An on-vehicle apparatus that performs inside / outside determination to determine the position of the portable device. Used in vehicles,
A response signal is sent back for each of the transmitting antennas based on the reception of the signals carried on the radio wave in order from the transmitting antennas (31, 31a, 31b, 31c) carried by the user and arranged in plural on the vehicle An on-vehicle apparatus including a position determination unit (306a) that determines the position of the portable device to be
The transmitting antenna is disposed in a boundary area of the vehicle inside and outside of the vehicle such that the direction of the magnetic field vector is different at the boundary area.
An acquisition unit for acquiring the response signal including the direction of the magnetic field vector of the transmitting antenna specified by the portable device based on the radio wave transmitted from the transmitting antenna and sent back from the portable device Equipped with 303a),
The position determination unit determines whether the portable device is located inside or outside of the vehicle interior of the vehicle based on a combination of directions of the magnetic field vectors included in the response signals for each of the transmission antennas acquired by the acquisition unit. In-vehicle device that makes a decision. A reply unit (23) for returning a response signal based on reception of a signal carried on radio waves from a transmitting antenna (31, 31a, 31b, 31c) carried by a user and disposed in a vehicle A portable device,
A measuring unit (220) for measuring the received signal strength of the signal received from the transmitting antenna, which is arranged in a boundary area inside and outside the vehicle compartment of the vehicle so that the direction of the magnetic field vector is different at the boundary area;
The magnetic field vector of the transmitting antenna is placed based on radio waves transmitted from the transmitting antenna which is arranged so that the direction of the magnetic field vector is different in the boundary area inside and outside the vehicle interior of the vehicle. And a vector direction identification unit (201) for identifying the direction of
The portable unit returns the response signal including the received signal strength measured by the measurement unit and the direction of the magnetic field vector identified by the vector direction identification unit. A response signal is sent back for each of the transmitting antennas based on the reception of the signals carried on the radio wave in order from the transmitting antennas (31, 31a, 31b, 31c) carried by the user and arranged in a plurality of vehicles. A portable unit provided with a reply unit (23a),
The magnetic field vector of the transmitting antenna is placed based on radio waves transmitted from the transmitting antenna which is arranged so that the direction of the magnetic field vector is different in the boundary area inside and outside the vehicle interior of the vehicle. And a vector direction identification unit (201) for identifying the direction of
The portable device which replies the response signal including the direction of the magnetic field vector specified by the vector direction specifying unit.

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