JP2008184849A - Keyless entry device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a keyless entry device capable of easily determining a position of a portable machine, by maximally approaching a boundary surface for discriminating the position of the portable machine, to a shape of a car body. <P>SOLUTION: A vehicle side device 2 has a vehicle side control part 12 for performing predetermined control when authenticating an answer signal from the portable machine 3. The portable machine 3 has a portable machine control part 22 detecting respective strengths of signals transmitted from a plurality of transmission antennas of the vehicle side device 2. The vehicle side control part 12 and the portable machine control part 22 respectively calculate a distance between the portable machine 3 and the transmission antennas 15 on the signal strengths from the plurality of transmission antennas 15 detected by the portable machine 3, and calculate two distances among the calculated distance or a total distance of adding a numeric value of multiplying the two distances by a predetermined factor, and determine in which of the inside and outside of a predetermined boundary surface 30 the portable machine 3 is positioned by comparing the total distance with a predetermined threshold value. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a keyless entry device that locks and unlocks a vehicle door by performing wireless communication between a vehicle-side device and a portable device, and in particular, determines whether the portable device is inside or outside a predetermined boundary surface. It is related with the keyless entry device which can do.

  2. Description of the Related Art Conventionally, a keyless entry device that performs wireless communication between a vehicle-side device provided in a vehicle and a portable device carried by a user and locks / unlocks the door of the vehicle is known. In recent years, when a portable device approaches the vehicle, communication is automatically performed between the vehicle-side device and the portable device, and if the ID that is uniquely set for each portable device is authenticated, A passive keyless entry device that performs locking and unlocking operations is also known.

  In passive / keyless entry devices, the content of operation differs depending on which region the portable device is in, so it is necessary to determine whether the portable device is located inside or outside a predetermined boundary surface with respect to the vehicle. . Here, the vehicle-side device is provided with a transmission antenna that transmits a signal, and the portable device can calculate the distance to the transmission antenna by detecting the signal strength from the transmission antenna. By setting a threshold for this distance and comparing it with the distance calculated from the actually detected signal strength, it is determined whether the portable device is located inside or outside the spherical boundary surface centered on the position of the transmitting antenna be able to.

In addition, the vehicle is provided with a plurality of transmission antennas, the distance between each transmission antenna and the portable device is calculated, and the distance between each transmission antenna and the portable device is compared with a predetermined threshold value. It is also possible to determine whether the portable device is located inside or outside the boundary surface connecting the plurality of spherical boundary surfaces. For example, Patent Document 1 discloses a method for calculating the distance from the transmission antenna based on the signal intensity and performing the inside / outside determination of the boundary surface.
JP 2001-204058 A

  However, since the cross-sectional shape of the vehicle in the horizontal direction is generally rectangular, it is necessary to determine whether the portable device is located on the inside or outside of the spherical surface centering on the transmitting antenna or the boundary surface combining a plurality of them as in the past. Then, there is a problem that the accuracy of determination is low because the boundary surface does not match the shape of the vehicle. It is also possible to detect the signal strength from multiple transmitting antennas with a portable device, determine the absolute position of the portable device from them, and determine whether the position is within a predetermined range. There has been a problem that the processing for determining and determining is complicated.

  The present invention has been made in view of the above problems, and provides a keyless entry device that can make the boundary surface for determining the position of the portable device as close as possible to the shape of the vehicle body and easily determine the position of the portable device. The purpose is to provide.

In order to solve the above-described problem, a keyless entry device according to the present invention includes a vehicle-side transmission unit that is provided in a vehicle and is connected to a plurality of transmission antennas that transmit request signals, and a vehicle-side reception unit that receives an answer signal. In a keyless entry device having a vehicle-side device, a portable device reception unit that receives the request signal, and a portable device that includes a portable device transmission unit that transmits an answer signal,
The vehicle-side device includes a vehicle-side control unit that performs predetermined control when an answer signal from the portable device is authenticated, and the portable device detects each intensity of a signal transmitted from a plurality of transmission antennas of the vehicle-side device. A portable device control unit
The vehicle-side control unit or the portable device control unit calculates a distance between the portable device and the transmission antenna with respect to signal intensities from a plurality of transmission antennas detected by the portable device, and the portable device out of the calculated distances And calculating the total distance obtained by adding the two distances between the two different transmission antennas or the two distances multiplied by a predetermined coefficient, and comparing the total distance with a predetermined threshold value. Is determined to be located inside or outside a predetermined boundary surface.

  Further, in the keyless entry device according to the present invention, the vehicle-side control unit or the portable device control unit makes one set with any two of the plurality of transmission antennas, and is different from the one set of transmission antennas. Create another set, thereby creating a plurality of pairs consisting of a pair of antennas, and for each of the plurality of sets, the distance from each transmitting antenna or the total distance obtained by multiplying the distance by a predetermined coefficient is added. While calculating, comparing each total distance with a predetermined threshold value, it is determined whether the portable device is located inside or outside a predetermined boundary surface.

  Furthermore, in the keyless entry device according to the present invention, the vehicle-side control unit or the portable device control unit compares the total distance with a predetermined threshold value, and further compares the distance from each transmission antenna with a predetermined threshold value. It is configured to determine whether the portable device is located inside or outside a predetermined boundary surface.

  Furthermore, the keyless entry device according to the present invention is configured such that a plurality of the transmission antennas are provided in the front-rear direction of the vehicle.

  The keyless entry device according to the present invention is characterized in that the threshold value is set such that a predetermined boundary surface determined by the vehicle-side control unit or the portable device control unit is a surface near the vehicle body of the vehicle. It is configured.

  According to the keyless entry device according to the present invention, the vehicle-side control unit or the portable device control unit calculates the distance between the portable device and the transmission antenna for the signal intensities from the plurality of transmission antennas detected by the portable device, Of the calculated distances, calculate two distances between the portable device and two different transmission antennas, or a total distance obtained by multiplying the two distances by a predetermined coefficient, and compare the total distance with a predetermined threshold value. By determining whether the portable device is located inside or outside the predetermined boundary surface, the predetermined boundary surface can be set to be elliptical, so that the position of the portable device can be easily determined by the boundary surface close to the shape of the vehicle body. Judgment can be made.

  Further, according to the keyless entry device according to the present invention, the vehicle-side control unit or the portable device control unit makes one set with any two of the plurality of transmission antennas, and is different from the one set of transmission antennas. This creates a plurality of pairs consisting of a pair of antennas, and for each of the plurality of pairs, calculates the distance from each transmitting antenna or the total distance obtained by summing the distance multiplied by a predetermined coefficient. In addition, by comparing each total distance with a predetermined threshold value to determine whether the portable device is located inside or outside the predetermined boundary surface, the outer edge surface connecting a plurality of elliptical spheres is set as the predetermined boundary surface Therefore, a boundary surface closer to the shape of the vehicle body can be set.

  Furthermore, according to the keyless entry device according to the present invention, the vehicle-side control unit or the portable device control unit compares the total distance with a predetermined threshold, and further compares the distance from each transmission antenna with the predetermined threshold. By determining whether the portable device is located inside or outside the predetermined boundary surface, it is possible to set the outer edge surface combining the ellipsoidal and spherical surfaces as the predetermined boundary surface. The face can be set.

  Furthermore, according to the keyless entry device according to the present invention, by providing a plurality of transmission antennas in the front-rear direction of the vehicle, the predetermined boundary surface can be set longer in the front-rear direction, and the boundary surface close to the shape of the vehicle body can be obtained. Can be set.

  According to the keyless entry device according to the present invention, the threshold value is set so that the predetermined boundary surface determined by the vehicle-side control unit or the portable device control unit is a surface near the vehicle body of the vehicle. It can be easily determined whether the vehicle is located inside or outside the vehicle.

  Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a schematic diagram of a keyless entry device according to this embodiment. The keyless entry device according to the present embodiment locks or unlocks the door 1a of the vehicle 1. The vehicle-side device 2 is provided on the vehicle 1, the user carries the portable device 3, and the vehicle-side device. Wireless communication is performed between the mobile phone 3 and the portable device 3 to perform authentication, locking / unlocking commands, and the like. The vehicle-side device 2 has a plurality of transmission antennas 15 at various locations of the vehicle 1, and a request signal is transmitted from each transmission antenna 15 to the portable device 3. The request signal is a low frequency signal.

  Hereinafter, a case where the user approaches the vehicle 1 and unlocks the door 1a will be mainly described. In the present embodiment, in order to unlock the door 1a, the user having the portable device 3 needs to press the request switch 16 provided near the door knob 1b of the door 1a. When the request switch 16 is pressed, communication such as authentication is performed between the vehicle-side device 2 and the portable device 3, and when the authentication is made, the vehicle-side device 2 unlocks the door 1a.

  Next, the structure of the vehicle side apparatus 2 and the portable device 3 is demonstrated. FIG. 2 shows a block diagram of the keyless entry device. As shown in this figure, the vehicle-side device 2 includes a vehicle-side receiver 10 that receives an answer signal from the portable device 3, a vehicle-side transmitter 11 that transmits a request signal to the portable device 3, and an answer signal. And a vehicle-side control unit 12 that performs various controls when the request switch 16 is pressed.

  In addition, the vehicle-side control unit 12 stores information necessary for control, such as V-ID (Vicle-ID), which is a vehicle-specific identification code, and IDs of a plurality of portable devices capable of operating one vehicle. 13 and the request switch 16 described above are connected. Furthermore, a receiving antenna 14 for receiving an answer signal is connected to the vehicle-side receiving unit 10, and a plurality of transmitting antennas 15 and 15 for transmitting a request signal are connected to the vehicle-side transmitting unit 11. The plurality of transmission antennas 15 and 15 are provided at various locations inside and outside the vehicle 1, respectively.

  The portable device 3 includes a portable device receiver 20 that receives a request signal from the vehicle-side device 2, a portable device transmitter 21 that transmits an answer signal to the vehicle-side device 2, and various types of signals when receiving a request signal. It has the portable device control part 22 which performs control, and the memory 24 which memorize | stored ID, V-ID, etc. which were set to the own machine. In addition, the portable device receiving unit 20 and the portable device transmitting unit 21 are connected to a three-axis antenna 23 that transmits and receives request signals and answer signals and has directivity characteristics in directions orthogonal to each other.

  The portable device control unit 22 is an intermittent reception state in which the sleep state in which power consumption is substantially zero and the receivable state are switched by a wakeup signal included in the request signal from the vehicle-side device 2 received by the portable device reception unit 20. Switches to a normal state in which the receivable state continues. In addition, the portable device control unit 22 performs various operations based on commands included in the request signal. Furthermore, the portable device control unit 22 can detect the intensity of the signal received by the triaxial antenna 23.

  FIG. 3 shows the arrangement of the receiving antenna 14 and the transmitting antenna 15 in the vehicle 1 and the region set for position determination. The line of the vehicle 1 shown in FIG. 3 schematically represents the vehicle body surface. One receiving antenna 14 is provided in the vehicle 1, while a plurality of transmitting antennas 15 are provided outside and inside the vehicle 1 from the transmitting antennas 15a to 15f. In the present embodiment, three transmission antennas 15 a to 15 c are provided in the front-rear direction inside the vehicle interior of the vehicle 1, and three transmission antennas 15 d to 15 f are provided outside the vehicle interior of the vehicle 1. .

  In the present embodiment, it is determined whether the portable device 3 is located inside or outside the vehicle 1. The determination is made first by determining whether the portable device 3 is located in the region α, β, or γ by a simple method although the accuracy is not high. This determination is made based on the strength of the signal received by the portable device 3 from the transmission antennas 15 a to 15 c, and the portable device 3 is located either inside or outside the first boundary surface 30 set inside the vehicle 1. This is done by determining whether the portable device 3 is located inside or outside the second boundary surface 31 set outside the vehicle 1. Specifically, when the portable device 3 is located outside the second boundary surface 31, it is determined that the portable device 3 is located in the region α, and the portable device 3 is the second boundary surface. 31 is located outside the first boundary surface 30, it is determined that the portable device 3 is located in the region β, and the portable device 3 is located inside the first boundary surface 30. If the mobile device 3 is located in the region γ, the mobile device 3 is determined to be located in the region γ. Here, the first boundary surface 30 and the second boundary surface 31 are both virtual surfaces set in advance.

  When it is determined whether the portable device 3 is located in the region α, β, or γ, and the portable device 3 is located in a region α and a region γ that are separated from the vehicle body surface of the vehicle 1 to some extent. First, the inside / outside determination is performed as it is, and when the portable device 3 is located in the region β in the vicinity of the vehicle body surface of the vehicle 1, the position is determined by a more accurate method.

  Setting of the first boundary surface 30 is performed as follows. First, the portable device 3 is moved in advance along the vehicle body surface, and the signal strength from the transmission antenna 15 of the vehicle 1 in the portable device 3 in the vicinity of the vehicle body surface is measured at a plurality of positions. The distance to each transmitting antenna 15 is calculated. Note that the relationship between the signal strength and the distance to the transmission antenna 15 is measured in advance. Here, in a state where the portable device 3 is positioned at a predetermined position, the signal strengths from the transmission antennas 15a to 15c provided inside the vehicle 1 are detected, and from the signal strength, each of the portable devices 3 at the predetermined position is detected. The distances to the transmission antennas 15a to 15c are calculated and used as data at the positions. In this case, the data at the position is constituted by three distance data.

  Next, the total distance (La + Lb) obtained by summing the distance La to the transmission antenna 15a and the distance Lb to the transmission antenna 15b is obtained for the acquired data at all positions measured along the vehicle body surface. Then, min (La + Lb) that minimizes the value is specified. Similarly, for the transmission antenna 15b and the transmission antenna 15c, the total distance (Lb + Lc) is obtained for the acquired data at all positions, and min (Lb + Lc) at which the value is minimized is specified.

  By the way, the value represented by (Lb + Lc) means that an ellipsoidal surface passing through the position of the position portable device 3 is specified by focusing on each position of the transmission antenna 15a and the transmission antenna 15b, and min ( By specifying La + Lb), an elliptical surface having a major axis radius of min (La + Lb) / 2 is specified with the respective positions of the transmission antenna 15a and the transmission antenna 15b as focal points. The value represented by min (La + Lb) means that the smallest ellipsoidal surface focusing on each position of the transmitting antenna 15a and the transmitting antenna 15b is specified, and the position of the portable device 3 that is min (La + Lb) is In the vicinity of the vehicle body surface, this is a point on the side of the central position between the transmitting antenna 15a and the transmitting antenna 15b (horizontal direction in FIG. 3), and this elliptical spherical surface is a first line indicated by a solid line and a dotted line in FIG. An elliptic spherical surface 35 is obtained. In this example, La corresponds to one of the two distances, Lb corresponds to the other of the two distances, and (La + Lb) or min (La + Lb) corresponds to the total distance.

  Also, by min (Lb + Lc), an elliptical surface having a major axis radius of min (Lb + Lc) / 2 with the respective positions of the transmission antenna 15b and the transmission antenna 15c as a focal point is specified. The position of min (Lb + Lc) is in the vicinity of the vehicle body surface, and is a point on the side of the central position between the transmission antenna 15b and the transmission antenna 15c (horizontal direction in FIG. 3). The second elliptical spherical surface 36 is indicated by a solid line and a dotted line. These ellipsoidal surfaces are set as a part of the first boundary surface 30. In this example, Lb corresponds to one of the two distances, Lc corresponds to the other of the two distances, and (Lb + Lc) or min (Lb + Lc) corresponds to the total distance.

  The transmission antenna 15a and the transmission antenna 15b make one set, and the transmission antenna 15b and the transmission antenna 15c make at least one transmission antenna 15c different from the one set of transmission antennas 15a and 15b, As a result, a plurality of pairs of antennas, in this case, two pairs are formed.

  Moreover, the position where the distance to the transmission antenna 15a is the smallest is specified among the distance data of all the positions measured along the vehicle body surface, and the distance between the position and the transmission antenna 15a is specified as minLa. Similarly, minLb and minLc are specified for the transmission antennas 15b and 15c. As a result, a spherical surface with the transmission antenna 15a as the center and a radius of minLa, a spherical surface with the transmission antenna 15b as the center and a radius of minLb, and a spherical surface with the transmission antenna 15c as the center and a radius of minLc are specified. The In addition, since La, Lb, and Lc specify the spherical surface in which the surrounding surface passes the position of the portable device 3 among the spherical surfaces centering on the transmitting antennas 15a, 15b, and 15c, respectively, the distance from the transmitting antenna 15a is usually set. The position evaluated as the minimum is near the vehicle body surface and the center position of the windshield, and the position evaluated as the minimum distance to the transmission antennas 15b and 15c is near the vehicle body surface, and these transmission antennas It is a point on the side (horizontal direction in FIG. 3). These spherical surfaces are referred to as a first spherical surface 37, a second spherical surface 38, and a third spherical surface 39 as shown by solid lines and dotted lines in FIG. These spherical surfaces are set as a part of the first boundary surface 30.

  As shown in FIG. 3, the outer edge surface connecting the first elliptic spherical surface 35 and the second elliptic spherical surface 36, the first spherical surface 37, the second spherical surface 38, and the third spherical surface 39 is a first boundary indicated by a solid line. Set as face 30. Note that the sizes of the spherical surface and the elliptical sphere can be adjusted by multiplying the distance by a predetermined coefficient. That is, for example, the first ellipsoidal sphere 35 is an ellipsoidal surface in which (La + Lb) has a constant value (min (La + Lb)), but each data has an ellipsoid in which (kLa + kLb) has a constant value. May be specified. In this case, when k is larger than 1, the distance is increased and the size of the elliptic sphere is increased, and when k is less than 1, the distance is decreased and the size of the elliptic sphere can be decreased.

  Next, the setting of the second boundary surface 31 will be described. The second boundary surface 31 is specified by the signal strength from each transmission antenna 15 of the vehicle 1 when the portable device 3 is moved along the vehicle body. Specifically, at all measured points, among the three data indicating the distance to each antenna, it is specified which distance to the transmission antenna 15 is the smallest, and the distance to the transmission antenna 15a is the smallest. A set b having a minimum distance between the set a and the transmission antenna 15b and a set c having a minimum distance from the transmission antenna 15c are created. The front area of the vehicle 1 has the smallest distance to the transmission antenna 15a, and the data acquired in this area corresponds to the data of the set a, and the rear area of the vehicle 1 has the smallest distance to the transmission antenna 15c. The data acquired in step 1 corresponds to the data of the set c, and the distance in the front-rear direction intermediate region of the vehicle 1 with the transmission antenna 15b is minimum, so the data acquired in this region corresponds to the data of the set b. Next, the maximum value of the distance to the transmission antenna 15a in the set a is specified, and this is multiplied by a predetermined numerical value exceeding 1. And the spherical surface 40 centering on the transmitting antenna 15 in which this value becomes a radius is specified. Similarly, the sets b and c are similarly performed to specify the spherical surfaces 41 and 42, respectively. An outer edge surface connecting these spherical surfaces is set as the second boundary surface 31.

  In this example, the data when the portable device 3 is moved along the inside of the vehicle body is used. However, the data when the portable device 3 is moved along the outside of the vehicle may be used. Although it is multiplied by a value that exceeds, a predetermined numerical value may be added, or a value less than 1 may be multiplied to make the second boundary surface 31 slightly smaller.

  In the memory 13 of the vehicle side device 2, an ID necessary for authentication of the portable device 3, threshold values for determining the inside / outside of the first boundary surface 30 and the second boundary surface 31, and the vicinity of the vehicle inner / outer boundary surface And data for determining the position of the portable device 3 are stored. The data for determining the position of the portable device 3 in the region β has a lot of data that associates the strength of the radio wave from each transmission antenna 15 with the identification code of the transmission antenna 15 for each of the inside and the outside of the vehicle 1. It is calculated from the inner data group and the outer data group, and is a parameter value for calculating the Mahalanobis distance for the actually measured intensity data.

  Each piece of data in the inner data group includes identification information indicating which transmission antenna 15 is associated with the radio wave intensity from each of the transmission antennas 15 in the vicinity of the vehicle body in the vehicle 1 and the corresponding radio wave. Strength. Such data is acquired in advance over substantially the entire inner circumference of the vehicle 1 to form an inner data group. As for the outer data group, data is acquired in advance in the same manner as the inner data group over almost the entire circumference in the vicinity of the vehicle body outside the vehicle 1 and is configured.

  The acquisition of these data is performed for the actual vehicle 1 using the portable device 3 or the strength measuring device at the time of product development. Alternatively, data can be acquired on the production line. Further, a parameter for calculating the Mahalanobis distance is calculated from the inner data group and the outer data group, and is stored in the memory 13.

  When the portable device 3 is in the region β, when the position is determined, a signal is continuously transmitted from each transmission antenna 15 at a predetermined time interval, and the portable device 3 transmits from each transmission antenna 15. Depending on the reception timing of the received signal, it is identified which antenna is the intensity data and the intensity data is measured. And the signal containing this information is transmitted to the vehicle side. On the vehicle side, the position of the portable device 3 is specified using four data having the highest strength, and the Mahalanobis distance with the inner data group and the Mahalanobis distance with the outer data group are determined using the parameters stored in the memory 13. Each is calculated, and the smaller Mahalanobis distance, that is, which set is approximated is determined, and it is determined that the portable device 3 is located on that side.

  Next, the operation of the keyless entry device will be described. In FIG. 4, the flowchart about the operation | movement at the time of unlocking a door is shown. FIG. 5 shows a chart of signals transmitted from the vehicle side device 2 and the portable device 3 in the flow of FIG. The keyless entry device of the present embodiment is such that when a request switch 16 provided in the vehicle 1 is pressed, wireless communication is performed between the vehicle side device 2 and the portable device 3 and the door is unlocked. is there. Therefore, the flow starts when the user first presses the request switch 16 of the vehicle 1 (S1).

  When the request switch 16 is pressed, the vehicle-side control unit 12 causes the vehicle-side transmission unit 11 to transmit a request signal LF1 (S2). As shown in FIG. 7, the request signal LF1 includes a signal A including a wakeup signal and a command signal CMD. The command signal CMD includes V-ID (Vhicle-ID) information, which is a vehicle-specific identification code.

  When the portable device 3 receives the request signal LF1 by the portable device receiver 20, the portable device controller 22 changes from the intermittent reception state to the continuous reception state by the wakeup signal, and the V-ID included in the request signal LF1 is It is determined whether or not it matches the stored V-ID. If the V-IDs do not match, the flow ends there. If the V-IDs match, the portable device control unit 22 causes the portable device transmission unit 21 to transmit the answer signal RF1 (S5).

  When the vehicle-side receiver 10 receives the answer signal RF1 (S6), the vehicle-side controller 12 causes the vehicle-side transmitter 11 to transmit a position confirmation signal LF2. As shown in FIG. 7, the position confirmation signal LF2 includes a wake-up signal as with the request signal LF1, and sequentially transmits a signal A including the ID of the portable device, a signal including the command signal CMD, and the transmission antennas 15a to 15f. And a plurality of Rssi measurement signals.

  The Rssi measurement signal transmitted from each of the transmission antennas 15a to 15f is a pulse-like signal having a predetermined intensity and continuing for a predetermined time as shown in FIG. 5, and the reception intensity is measured on the portable device 3 side. Used to do. Each Rssi measurement signal is transmitted from the transmitting antennas 15a to 15f in a predetermined order and at a predetermined time interval by the vehicle-side transmission unit 11 after a predetermined time has elapsed after receiving the RF1 signal from the portable device. The portable device 3 stores information on which signal from which antenna is transmitted at which timing from reception of the RF1 signal on the vehicle side, and starts reception from the time when the RF1 signal is received. Measure time. Then, by comparing the two, it is possible to identify from which transmitting antenna 15 the Rssi measurement signal is transmitted. Further, the time interval of signals transmitted from the transmission antennas 15a to 15f is set to be sufficiently short. Therefore, it can be considered that the position of the portable device 3 carried or placed by a person does not move greatly during one period necessary for transmission from all the transmission antennas 15a to 15f. Strictly speaking, when the portable device is moving, it is not intensity data at a fixed position, but since the time interval is sufficiently short as described above, the acquired data can be regarded as distance data at a predetermined position of the portable device. If one cycle is sufficiently early, the data may not necessarily be data in one cycle, but may be an average value with the next cycle, or the like.

  The position confirmation signal LF2 including the Rssi measurement signal transmitted from each of the transmission antennas 15a to 15f is received by the portable device receiver 20 of the portable device 3 (S8). The portable device control unit 22 measures the strength of each Rssi measurement signal with the triaxial antenna 23 as described above, and uses the strength data information for each transmission antenna obtained from the triaxial antenna 23 as the answer signal RF2. It transmits to the side apparatus 2 (S9). At this time, the answer signal RF2 is also transmitted including the HU-ID, which is an ID uniquely set for each portable device. The signal strength measurement is not limited to measuring the strength on the portable device 3 side by transmitting an Rssi measurement signal from the vehicle 1 side, but the strength of the request signal itself transmitted from the vehicle 1 side. You may measure.

  The vehicle side transmitter 11 of the vehicle side device 2 receives the answer signal RF2 from the portable device 3 (S10). When the answer signal RF2 is received, the vehicle-side control unit 12 determines whether or not the HU-ID included therein matches the one registered in the vehicle (S11). Here, if the HU-ID does not match that registered in the vehicle, the flow ends there. On the other hand, if the HU-ID matches that registered in the vehicle, it is next determined whether the portable device 3 is located inside or outside the vehicle 1 (S12).

  At the time of transmission / reception of the request signal LF1, the answer signal RF1 is transmitted after a different time for each portable device 3 after transmitting the request signal LF1, and any one of the plurality of portable devices 3 is measured by measuring this time. The portable device 3 is specified quickly and easily depending on whether there is a response. At the time of transmission / reception of the request signal LF2, accurate authentication using the individual ID of the portable device having a larger amount of information and confirmation of the position are first performed on the portable device 3 detected in the request signal LF1. And when it cannot authenticate, the same operation | movement is performed with respect to each portable device 3. FIG. Note that the identification of the portable device 3 in the request signal LF1 may be omitted and only the authentication of the portable device 3 here may be performed, or the authentication of each portable device 3 may be performed after the transmission of the Rssi measurement signal. it can.

  The position of the portable device 3 is determined according to the following flow. In FIG. 6, the flowchart of the position determination of the portable device 3 is shown. First, the vehicle-side control unit 12 specifies the transmission antenna from the data included in the answer signal RF2 transmitted from the portable device 3 and the transmission antenna from which the intensity is transmitted (S12-1). . Next, by determining the strength, it is determined whether the position of the portable device 3 relative to the vehicle 1 corresponds to any of the regions α, β, and γ shown in FIG.

  In order to determine whether the portable device 3 is located inside or outside the first boundary surface 30 and the second boundary surface 31, the vehicle-side control unit 12 uses the transmission antenna among the intensity data acquired in S12-1. Distances La, Lb, and Lc are calculated for the intensity data from 15a to 15c, respectively (S12-2). Further, a total distance (La + Lb) obtained by adding the distance La and the distance Lb and a total distance (Lb + Lc) obtained by adding the distance Lb and the distance Lc are calculated (S12-3).

  Next, the distances La, Lb, and Lc are compared with a predetermined threshold value for determining the inside / outside of the first boundary surface 30 (S12-4). Here, the threshold for the distance La is minLa, the threshold for the distance Lb is minLb, the threshold for the distance Lc is minLc, and these are stored in the memory 13. The vehicle-side control unit 12 reads each threshold value from the memory 13 and compares it with each distance. Further, as described above, the measured distances La, Lb, and Lc may be multiplied by a predetermined coefficient and then compared with each threshold value. If any one or more of the distances La, Lb, and Lc is smaller than the threshold value, the portable device 3 is determined to be located inside the first boundary surface 30, that is, in the region γ, and the portable device 3 It is determined that the vehicle is located in the vehicle (S12-5). If the distances La, Lb, and Lc are all greater than the threshold value, the total distance (La + Lb) is compared with the predetermined threshold value for the total distance (Lb + Lc) (S12-6). Here, the threshold for the total distance (La + Lb) is min (La + Lb), and the threshold for the total distance (Lb + Lc) is min (Lb + Lc). Further, as described above, the total distance may be calculated after multiplying each measured distance La, Lb, Lc by a predetermined coefficient and compared with each threshold value. If at least one of the total distance (La + Lb) and the total distance (Lb + Lc) is smaller than the threshold value, the portable device 3 is determined to be located inside the first boundary surface 30, that is, in the region γ, and the portable device 3 3 is determined to be located in the vehicle (S12-7). When both the total distance (La + Lb) and the total distance (Lb + Lc) are larger than the threshold value, it is determined that the portable device 3 is located outside the first boundary surface (S12-8).

  Subsequently, the magnitudes of the distances La, Lb, Lc and a predetermined threshold for determining the inside / outside of the second boundary surface 31 are compared (S12-9). The threshold for the distance La here is the radius of the surface 40, the threshold for the distance Lb is the radius of the surface 41, and the threshold for the distance Lc is the radius of the surface 42, which are stored in the memory 13. Yes. The vehicle-side control unit 12 reads each threshold value from the memory 13 and compares it with each distance. When the distances La, Lb, and Lc are all greater than the threshold value, the portable device 3 is determined to be located outside the second boundary surface 31, that is, in the region α, and the portable device 3 is located outside the vehicle. (S12-10). On the other hand, if any one or more of the distances La, Lb, and Lc is smaller than the threshold value, it is determined that the portable device 3 is located inside the second boundary surface 31 (S12-11). This means that it is determined that the portable device 3 is located in the region β.

  Thus, the distance is calculated from the intensity data, and the accuracy of the absolute position of the obtained portable device 3 is not so high, but it is possible to sufficiently determine which region the portable device 3 is in. Since the region α and the region γ are regions that are separated to some extent from the vehicle inner / outer boundary surface as shown in FIG. 3, if the position of the portable device 3 is determined as the region α or the region γ, Even if the position accuracy itself is not so high, it can be determined with sufficient accuracy whether the portable device 3 is inside or outside the vehicle. In other words, in the case of data that has been confirmed or calculated that no erroneous determination is made even if an error with respect to a normal value is taken into account in the measured intensity data, the position is immediately determined based on the data. I have to.

  On the other hand, if it is determined that the portable device 3 is located in the region β, the vehicle-side control unit 12 reads parameters necessary for calculating the Mahalanobis distance from the memory 13 (S12-12), and the intensity obtained from the portable device 3 The Mahalanobis distance between the data and the inner data group and the Mahalanobis distance between the intensity data obtained from the portable device 3 and the outer data group are calculated (S12-13).

  After calculating the Mahalanobis distance, the vehicle-side controller 12 determines whether the Mahalanobis distance from the intensity data obtained from the portable device 3 is closer to the outer data group than the inner data group (S12-14). When it is close to the outside data group, the vehicle-side control unit 12 determines that the portable device 3 is located outside the vehicle (S12-15), and ends the position determination flow. If it is closer to the inner data group than the outer data group, the vehicle-side control unit 12 determines that the portable device 3 is located in the vehicle (S12-16), and ends the position determination flow.

  Thereafter, the vehicle-side control unit 12 performs different control depending on whether the portable device 3 is inside or outside the vehicle (S13). If it is determined that the position of the portable device 3 is in the vehicle, the flow is terminated as it is. When the request switch 16 is pressed to unlock the door, the portable device 3 should be outside the vehicle. When the portable device 3 is unlocked together with the user, the portable device 3 is held. Even a person who is not able to press the request switch 16 can unlock the door. In order to prevent this, when the portable device 3 is in the vehicle, the door is not unlocked. On the other hand, if it is determined that the position of the portable device 3 is outside the vehicle, an unlock command signal is output to the door locking device (not shown), and the door is unlocked (S14).

  Although the operation of unlocking the door by pressing the request switch 16 is shown here, the position determination of the portable device 3 can be similarly performed for the operation of locking the door, and control according to the result can be performed. Further, not only the door locking / unlocking operation, but also the operation of starting the engine according to the position of the portable device 3, the position of the portable device 3 is similarly determined, and the operation is performed according to the result. be able to.

  As described above, for the distance calculated based on the signal intensity from the plurality of transmission antennas 15 detected by the portable device 3, the total distance obtained by adding the two distances is calculated, and the magnitude of the predetermined threshold is compared By doing so, the boundary surface to be discriminated can be made into an elliptical sphere, so that the position of the portable device 3 can be determined by the boundary surface close to the shape of the vehicle body surface. Further, the total distance is calculated for each of a plurality of sets (a set of transmission antennas 15a and 15b and a set of transmission antennas 15b and 15c) having two of the three transmission antennas 15 provided inside the vehicle 1. Since the comparison is made with the threshold value, a plurality of elliptical spherical surfaces can be set as the boundary surface, and the boundary surface can be made closer to the shape of the vehicle body surface. Furthermore, since the distance from each transmission antenna 15 is also compared with the threshold value, a spherical surface centering on each transmission antenna 15 can also be a part of the boundary surface. Can be set as the boundary surface, and the boundary surface can be made closer to the shape of the vehicle body surface.

  In addition, first, an area where the portable device 3 is located is determined by a simple method, and when the portable device 3 is located in an area somewhat away from the vehicle body surface or inside the vehicle, the region determination result is used. When the portable device 3 is located in the area near the vehicle surface, the Mahalanobis distance is calculated and the position of the vehicle inside / outside is determined based on the Mahalanobis distance. Since it is only necessary to acquire detailed data for distance calculation only in the vicinity of the vehicle body surface, man-hours can be greatly reduced. In addition, when the portable device 3 is located in a region away from the body surface to some extent, the position determination can be performed without calculating the Mahalanobis distance, so that the processing time can be shortened.

As mentioned above, although embodiment of this invention was described, application of this invention is not restricted to these embodiment, It can apply variously within the range of the technical idea. In the embodiments described so far, the intensity data is converted into the corresponding distance. However, it is not always necessary to convert the intensity data into the distance, and any data corresponding to the distance may be used. For example, a predetermined calculation may be performed on the intensity data directly without converting it into a distance to obtain a value, and thereby the boundary surface may be specified. In this case, the data used when determining the position of the portable device can also be obtained intensity data.
In addition, as shown in FIG. 3, three transmission antennas 15 are provided inside and outside the vehicle 1, but the number and arrangement of the transmission antennas 15 are not limited to this. However, in order to calculate the total distance, at least two transmission antennas 15 are required inside the vehicle 1. It should be noted that the more transmission antennas 15 are, the more accurately the positions can be determined.

  Further, the setting of the first boundary surface 30 is not limited to that of the present embodiment shown in FIG. Since at least two transmission antennas 15 are provided on the inner side of the vehicle 1 as described above, one elliptical surface having these as a focal point may be used as a boundary surface, or more transmission antennas 15 may be disposed on the vehicle 1. It is also possible to provide a large number of elliptical spherical surfaces and use the outer edge surface as a boundary surface. On the other hand, a boundary surface having a shape closer to the vehicle body surface of the vehicle 1 can be set by overlapping a spherical surface centering on each transmission antenna 15 and using the outer edge surface as the boundary surface. Further, in the present embodiment, it is used for the inside / outside determination of the passenger compartment, but the present invention is not limited to this. For example, a virtual surface 10 cm away from the vehicle may be used as a boundary surface and used for internal / external determination with respect to the boundary surface. In addition, if the boundary of the seat is the boundary surface, or an ellipse is defined around the vehicle as a reference surface, this is used as the boundary surface, and unlocked when a person with a portable device enters the boundary surface. You can also do it.

  Further, in the present embodiment, the vehicle-side control unit 12 on the vehicle-side device 2 side determines the area and calculates the Mahalanobis distance between the data from the portable device 3 and each data group. Are stored in the same memory as each threshold value and parameters necessary for calculating the Mahalanobis distance, and the portable device control unit 22 performs the region determination and the Mahalanobis distance calculation, You may make it perform inside / outside determination.

  Further, in the present embodiment, the inside / outside discrimination is performed for each of the first boundary surface 30 and the second boundary surface 31, the inside / outside determination is performed as it is in the case of the regions α and γ, and the Mahalanobis distance is determined in the case of the region β. However, it is also possible to set a single boundary surface so that it substantially overlaps the vehicle body surface, and to determine whether the vehicle is inside or outside the vehicle only by determining whether the vehicle is inside or outside. However, in that case, the Mahalanobis distance is not used, and the accuracy of the determination is reduced.

It is a schematic diagram of the keyless entry device in this embodiment. It is a block diagram of a keyless entry device. It is the figure which showed the area | region setting of the position of the antenna provided in a vehicle, and portable device position determination. It is a flowchart in the case of unlocking operation | movement. It is a chart figure of the signal from a vehicle side apparatus and a portable machine. It is a flowchart of position determination of a portable machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Vehicle side apparatus 3 Portable machine 10 Vehicle side receiving part 11 Vehicle side transmission part 12 Vehicle side control part 13 Memory 14 Reception antenna 15 Transmission antenna 16 Request switch 20 Portable machine receiving part 21 Portable machine transmission part 22 Portable machine control part 23 Triaxial antenna

Claims (5)

A vehicle-side device provided with a vehicle-side transmitter connected to a plurality of transmission antennas provided in a vehicle and transmitting a request signal, a vehicle-side receiver that receives an answer signal, and a portable device receiver that receives the request signal In a keyless entry device having a portable device including a portable device and a portable device transmitter for transmitting an answer signal,
The vehicle-side device includes a vehicle-side control unit that performs predetermined control when an answer signal from the portable device is authenticated, and the portable device detects each intensity of a signal transmitted from a plurality of transmission antennas of the vehicle-side device. A portable device control unit
The vehicle-side control unit or the portable device control unit calculates a distance between the portable device and the transmission antenna with respect to signal intensities from a plurality of transmission antennas detected by the portable device, and the portable device out of the calculated distances And calculating the total distance obtained by adding the two distances between the two different transmission antennas or the two distances multiplied by a predetermined coefficient, and comparing the total distance with a predetermined threshold value. A keyless entry device characterized by determining whether or not is located inside or outside a predetermined boundary surface.   The vehicle-side control unit or the portable device control unit makes one set with any two of the plurality of transmission antennas, and makes another set different from the one set of transmission antennas. A plurality of sets of antennas are created, and for each of the plurality of sets, a total distance obtained by summing a distance from each transmission antenna or a value obtained by multiplying the distance by a predetermined coefficient is calculated, and each total distance and a predetermined threshold value are calculated. 2. The keyless entry device according to claim 1, wherein the portable device determines whether the portable device is located inside or outside a predetermined boundary surface.   The vehicle-side control unit or the portable device control unit compares the total distance with a predetermined threshold value, and further compares the distance from each transmission antenna with a predetermined threshold value, so that the portable device is placed either inside or outside the predetermined boundary surface. 3. The keyless entry device according to claim 2, wherein it is determined whether or not it is located.   4. The keyless entry device according to claim 2, wherein a plurality of the transmission antennas are provided in the front-rear direction of the vehicle.   The threshold value is set so that a predetermined boundary surface determined by the vehicle-side control unit or the portable device control unit is a surface in the vicinity of the vehicle body of the vehicle. The keyless entry device described in 1.

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