Location determination system

Abstract

To improve the accuracy of position determination.SOLUTION: A position determination system comprises: at least three first communication instruments 10A-10C for acquiring the distances to a portable terminal 3 by wireless communication with the portable terminal 3; and a position determination unit for determining the position of the portable terminal from the distances acquired by the at least three first communication instruments 10A-10C. The at least three first communication instruments 10A-10C include three first communication instruments 10A-10C arranged at mutually different positions when seen along a vehicle height direction. At least two first communication instruments of the three first communication instruments 10A-10C are arranged at mutually different positions in a longitudinal vehicle direction. At least two first communication instruments of the three first communication instruments 10A-10C are arranged at mutually different positions in a lateral vehicle direction. The at least three first communication instruments 10A-10C are provided at positions higher than the bottom edge of the side window of a vehicle 2.SELECTED DRAWING: Figure 2

Description

Technical Field

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[0001] The present disclosure relates to a position determination system.

Background Art

[0002] As a conventional position determination system, there is one that performs wireless communication between a plurality of communication devices provided in a vehicle and a mobile terminal carried by a user, and determines the position of the mobile terminal with respect to the vehicle using the propagation time or signal strength of radio waves. For example, Patent Document 1 describes a position determination system that determines the position of a mobile terminal using three communication devices arranged side by side in the vehicle width direction.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above position determination system, the accuracy of position determination may decrease depending on the position of the mobile terminal with respect to the vehicle.

[0005] An object of the present invention is to improve the accuracy of position determination in a position determination system for determining the position of a mobile terminal.

Means for Solving the Problems

[0006] One aspect of the present invention provides a position determination system comprising: at least three first communication devices provided in the passenger compartment of a vehicle, each acquiring the distance to a mobile terminal by wireless communication with the mobile terminal located around or inside the vehicle; and a position determination unit that determines the position of the mobile terminal from the distances acquired by each of the at least three first communication devices, wherein the at least three first communication devices include three first communication devices arranged at different positions when viewed along the vehicle height direction, at least two of the three first communication devices are arranged at different positions in the vehicle length direction, at least two of the three first communication devices are arranged at different positions in the vehicle width direction, and the at least three first communication devices are provided at a position higher than the lower edge of the vehicle's side window.

[0007] In this configuration, at least two of the three first communication devices, which are positioned at different locations when viewed along the vehicle height direction, are positioned at different locations in the vehicle length direction, and at least two of the three first communication devices are positioned at different locations in the vehicle width direction. Therefore, the accuracy of position determination in the vehicle length direction and vehicle width direction can be improved compared to the case where the three first communication devices are positioned on the same straight line extending in the vehicle length direction or vehicle width direction. [Effects of the Invention]

[0008] According to this disclosure, the accuracy of determining the location of a mobile device can be improved. [Brief explanation of the drawing]

[0009] [Figure 1] A block diagram of a position determination system according to an embodiment of the present disclosure. [Figure 2] A top view of the vehicle according to the above embodiment. [Figure 3] A side view of the vehicle according to the above embodiment. [Figure 4] A diagram showing the region according to the above embodiment. [Figure 5]A diagram showing the selection table according to the above embodiment. [Figure 6] A flowchart of the position determination process according to the above embodiment. [Modes for carrying out the invention]

[0010] Embodiments of this disclosure will be described below with reference to the attached drawings.

[0011] Referring to Figure 1, the location determination system 1 determines the location of the smartphone 3 either in the vicinity of the vehicle 2 (shown in Figure 2) (i.e., outside the vehicle compartment) or inside the vehicle compartment. The location determination system 1 is mounted on the vehicle 2. The location determination system 1 comprises three first communication devices 10A to 10C, four second communication devices 20A to 20D, and a control device 30. The smartphone 3 in this embodiment is an example of a mobile terminal according to this disclosure. The mobile terminal according to this disclosure is not limited to the smartphone 3 in this embodiment, and may be, for example, a tablet terminal or a wearable terminal.

[0012] In the following explanation, the longitudinal direction of vehicle 2, i.e., the vehicle length direction, may be referred to as the X direction, the lateral direction of vehicle 2, i.e., the vehicle width direction, may be referred to as the Y direction, and the vertical direction of vehicle 2, i.e., the vehicle height direction, may be referred to as the Z direction.

[0013] In the following explanation, when there is no need to distinguish between the three first communication devices 10A to 10C, one of them may simply be referred to as "first communication device 10." In the following explanation, when there is no need to distinguish between the four second communication devices 20A to 20D, one of them may simply be referred to as "second communication device 20." Also, in the following explanation, when there is no need to distinguish between the first communication device 10 and the second communication device 20, one of them may simply be referred to as "communication device."

[0014] The communication device is a wireless communication device that communicates wirelessly with smartphone 3. The communication device uses UWB (Ultra Wide Band) communication with smartphone 3.

[0015] The communication device obtains the distance between itself and smartphone 3 by communicating wirelessly with smartphone 3. When the communication device receives a request signal from smartphone 3, it sends a response signal to smartphone 3. When smartphone 3 receives the response signal from the communication device, it calculates the time Δt1 from when it sent the request signal until it received the response signal. Smartphone 3 sends information about time Δt1 to the communication device. The communication device calculates the time Δt2 from when it received the request signal until it sent the response signal. From times Δt1 and Δt2, the communication device calculates the signal propagation time between itself and smartphone 3. The communication device calculates and obtains the distance from itself to smartphone 3 by multiplying the propagation time by the signal speed.

[0016] As shown in Figures 2 and 3, the first communication device 10 is located inside the passenger compartment of the vehicle 2. In this embodiment, the first communication devices 10A and 10B are attached to a pair of front pillars RFP and LFP of the vehicle 2, respectively. The pair of front pillars RFP and LFP are located between the windshield WS, which is a non-metallic material such as glass located at the front of the passenger compartment, and the side window SW, which is a non-metallic material such as glass located at the side of the passenger compartment. In this embodiment, the first communication device 10C is attached to the rear window RW, which is a non-metallic material such as glass located at the rear of the passenger compartment. The first communication device 10C may also be attached to a peripheral member (not shown) made of resin located around the rear window RW. In other words, the first communication device 10C may be attached to a peripheral member arranged surrounding the rear window RW.

[0017] As shown in FIG. 2, when viewed along the Z direction of the vehicle 2, the first communication devices 10A to 10C are arranged at different positions from each other. In other words, one of the first communication devices 10 among the first communication devices 10A to 10C is arranged at a position different from the other first communication devices 10 in either the X direction or the Y direction. More specifically, when viewed along the Z direction of the vehicle 2, the first communication devices 10A to 10C are arranged at non-overlapping positions. In other words, when viewed along the Z direction of the vehicle 2, the first communication devices 10A to 10C are arranged at intervals from each other. The first communication devices 10A to 10C are arranged such that a triangle (indicated by a two-dot chain line in FIG. 2) is formed by three straight lines connecting each of the first communication devices 10A to 10C. In other words, the first communication devices 10A to 10C are not arranged on the same straight line.

[0018] The first communication device 10A and the first communication device 10B are arranged at the same position in the X direction. The first communication devices 10A, 10B and the first communication device 10C are arranged at different positions in the X direction. In other words, the first communication devices 10A, 10B and the first communication device 10C are arranged at different positions from each other when viewed along the Y direction of the vehicle 2.

[0019] The first communication devices 10A to 10C are arranged at different positions from each other in the Y direction. In other words, the first communication devices 10A to 10C are arranged at different positions from each other when viewed along the X direction of the vehicle 2. The first communication device 10A and the first communication device 10B are arranged symmetrically with respect to the vehicle body center line CL extending in the X direction. The first communication device 10C is arranged on the vehicle body center line CL. The arrangement of the first communication devices 10A to 10C may be changed according to the structure inside the vehicle cabin. For example, the first communication device 10A and the first communication device 10B may be arranged asymmetrically with respect to the vehicle body center line CL, and the first communication device 10C may be arranged offset from the vehicle body center line CL.

[0020] As shown in FIG. 3, the first communication devices 10A to 10C are arranged at the same height. The first communication devices 10A to 10C are arranged at a position higher than a reference plane RP parallel to the horizontal plane, passing through the lower end of the side window SW. Specifically, the reference plane RP is a plane parallel to the horizontal plane, passing through the lower end of the portion of the side window SW exposed to the outside when the vehicle 2 is viewed along the Y direction. In other words, the reference plane RP is a plane parallel to the horizontal plane, passing through the lower ends of the front pillars RFP and LFP. The first communication devices 10A and 10B and the first communication device 10C may be arranged at different heights. The first communication devices 10A to 10C may be arranged at different heights from each other.

[0021] As shown in FIG. 2, the second communication device 20 is arranged outside the vehicle compartment of the vehicle 2. In this embodiment, the second communication devices 20A and 20B are attached to a front bumper FB made of resin. In this embodiment, the second communication devices 20C and 20D are attached to a rear bumper RB made of resin.

[0022] As shown in FIG. 2, when the vehicle 2 is viewed along the Z direction, the second communication devices 20A to 20D are arranged at different positions from each other. In other words, one of the second communication devices 20 among the second communication devices 20A to 20D is arranged at a position different from the other second communication devices 20 in either the X direction or the Y direction. Further in other words, when the vehicle 2 is viewed along the Z direction, the second communication devices 20A to 20D are arranged at positions that do not overlap with each other. In other words, when the vehicle 2 is viewed along the Z direction, the second communication devices 20A to 20C are arranged at intervals from each other.

[0023] The second communication device 20A and the second communication device 20B are arranged at the same position in the X direction. The second communication device 20C and the second communication device 20D are arranged at the same position in the X direction. The second communication devices 20A and 20B and the second communication devices 20C and 20D are arranged at different positions from each other in the X direction. In other words, the second communication devices 20A and 20B and the second communication devices 20C and 20D are arranged at different positions from each other when the vehicle 2 is viewed along the Y direction.

[0024] The second communication devices 20A and 20C are located at the same position in the Y direction. The second communication devices 20B and 20D are located at the same position in the Y direction. The second communication devices 20A, 20C and 20B, 20D are located at different positions in the Y direction. In other words, the second communication devices 20A, 20C and 20B, 20D are located at different positions when viewing vehicle 2 along the X direction. The second communication devices 20A and 20B are located symmetrically with respect to the vehicle body centerline CL. The second communication devices 20C and 20D are located symmetrically with respect to the vehicle body centerline CL. The second communication devices 20A to 20D may be located at different positions in the Y direction. In other words, the second communication devices 20A to 20D may be located at different positions when viewing vehicle 2 along the X direction.

[0025] As shown in Figure 3, the second communication devices 20A to 20D are arranged at the same height. The second communication devices 20A to 20D may be arranged in different positions. The second communication device 20 is positioned lower than the reference plane RP.

[0026] As shown in Figure 2, the first communication device 10 and the second communication device 20 are positioned at different locations when the vehicle 2 is viewed along the Z direction. In other words, the first communication device 10 and the second communication device 20 are positioned at locations that do not overlap when the vehicle 2 is viewed along the Z direction. In other words, the first communication device 10 and the second communication device 20 are positioned at a distance from each other when the vehicle 2 is viewed along the Z direction. The first communication device 10C and the second communication devices 20C and 20D are positioned at approximately the same location in the X direction. The first communication device 10A and the second communication devices 20A and 20C are positioned at approximately the same location in the Y direction. The first communication device 10B and the second communication devices 20B and 20D are positioned at approximately the same location in the Y direction.

[0027] As shown in Figure 3, the first communication device 10 and the second communication device 20 are positioned at different heights. Specifically, the second communication device 20 is positioned lower than the first communication device 10 in the Z direction.

[0028] As shown in Figure 1, the control device 30 is electrically connected to the first communication devices 10A to 10C and the second communication devices 20A to 20D. The control device 30 receives the distance L1A to L1C between the first communication devices 10A to 10C and the smartphone 3 as input from each of the first communication devices 10A to 10C. The control device 30 also receives the distance L2A to L2D between the second communication devices 20A to 20D and the smartphone 3 as input from each of the second communication devices 20A to 20D.

[0029] The control device 30 is an ECU (Electronic Control Unit). The control device 30 consists of hardware such as a computer and input / output circuits, and software implemented on the computer. The control device 30 includes a position determination unit 31, a region determination unit 32, and a selection unit 33.

[0030] The position determination unit 31 determines the position of the smartphone 3. The position determination unit 31 receives the distances L1A to L1C from the first communication devices 10A to 10C to the smartphone 3 and the distances L2A to L2D from the second communication devices 20A to 20D to the smartphone 3 as input. The position determination unit 31 uses three of the distances L1A to L1C and L2A to L2D to determine the position of the smartphone 3 by trilateration and outputs the result.

[0031] If the three distances described later have not been selected by the selection unit 33, the position determination unit 31 determines the provisional position of the smartphone 3 using any three distances from distances L1A to L1C and L2A to L2D (in this embodiment, the three shortest distances from L1A to L1C and L2A to L2D). In determining the provisional position of the smartphone 3, the planar position of the smartphone 3 is determined. On the other hand, after the selection unit 33 has selected three distances, the position determination unit 31 determines the position of the smartphone 3 using those three distances. In determining the position of the smartphone 3, the spatial position of the smartphone 3 is determined.

[0032] In order to determine the spatial position of smartphone 3, that is, its position in the X, Y, and Z directions, theoretically, it is necessary to perform a position calculation using four distances obtained from four communication devices that are not on the same plane. If trilateration is performed using three distances obtained from three communication devices, two possible positions for smartphone 3 will be determined. However, by deciding in advance to adopt one of these two positions, the spatial position of smartphone 3 can be determined using three communication devices.

[0033] The region determination unit 32 receives the position of the smartphone 3 determined by the position determination unit 31. The region determination unit 32 determines the region to which the smartphone 3 belongs based on its position and outputs the result. Specifically, as shown in Figure 4, the region determination unit 32 sets regions A1 to A6 around the vehicle 2 and inside the vehicle, and determines which of regions A1 to A6 the smartphone 3 belongs to based on its position. In Figure 4, for clarity, only region A6 is shown with hatching.

[0034] If the three distances described later have not been selected by the selection unit 33, the region determination unit 32 determines the provisional region to which the smartphone 3 belongs based on the provisional position of the smartphone 3 determined by the position determination unit 31. On the other hand, after the three distances have been selected by the selection unit 33, the region determination unit 32 determines the region to which the smartphone 3 belongs based on the position of the smartphone 3 determined by the position determination unit 31 using those three distances.

[0035] Areas A1 to A5 are set around vehicle 2, and area A6 is set inside the vehicle's interior. Area A1 is located in front of vehicle 2. Area A2 is located to the right of vehicle 2. Area A3 is located to the right rear of vehicle 2. Area A4 is located to the left rear of vehicle 2. Area A5 is located to the left of vehicle 2. Area A6 is located inside the vehicle's interior. The area settings are not limited to these. Areas may be set according to the number and arrangement of communication devices.

[0036] The selection unit 33 receives the region to which the smartphone 3 belongs, as determined by the region determination unit 32. The selection unit 33 selects and outputs three distances to be used for position determination by the position determination unit 31, according to the region to which the smartphone 3 belongs. Specifically, the selection unit 33 selects the three distances to be used for position determination according to the selection table T shown in Figure 5. The selection table T is stored in a storage unit (not shown) of the control device 30.

[0037] The selection table T shows the priority order in which the selection unit 33 selects the three distances used for location determination when a region to which smartphone 3 belongs is given. In Figure 5, the code indicating the communication device that acquires that distance (for example, if the distance is L1A, the code 10A indicates the first communication device 10A) is written in parentheses next to the distance.

[0038] The selection unit 33 selects three distances according to the priority set for each of the regions A1 to A6. The selection unit 33 basically selects the three distances set to priority 1. The distances set to priority 2 to 5 are backups in case one of the three distances set to priority 1 is unavailable. If one of the three selected distances is unavailable due to a communication problem or malfunction of the communication device, the selection unit 33 selects the distance with the highest priority among the unselected distances in place of the unavailable distance.

[0039] Referring to selection table T, each of the regions A1 to A6 has three distances set as priority 1. Each of the regions A1 to A5 has priority 1 plus priorities 2 to 5. On the other hand, region A6 has only priority 1 set.

[0040] The three distances with priority 1 include at least one distance acquired by the first communication device 10. Furthermore, the three distances with priority 1 are selected such that, when viewing vehicle 2 along the Z direction, the lines connecting each of the three communication devices that acquire the three distances with priority 1 form a triangle. In other words, when viewing vehicle 2 along the Z direction, the three communication devices that acquire the three distances with priority 1 are not located on the same line. To put it another way, when viewing vehicle 2 along the Z direction, the three communication devices that acquire the three distances with priority 1 include at least two communication devices that are positioned differently in the X direction and at least two communication devices that are positioned differently in the Y direction.

[0041] In each of the priority levels 2 to 5 in regions A1 to A5, the priority of the distance acquired by the first communication device 10 located inside the vehicle's cabin is higher than the priority of the distance acquired by the second communication device 20. By setting the priority levels 2 to 5 in each of the regions A1 to A5 in this way, the first communication device 10, which is located inside the vehicle's cabin and has a lower risk of failure than the second communication device 20 located outside the vehicle's cabin, is selected preferentially, thereby improving the stability of the operation of the position determination system 1.

[0042] Figure 6 is a flowchart of the position determination process performed by the position determination system 1.

[0043] Referring to Figure 6, the location determination system 1 starts location determination processing when the control device 30 detects the approach of a user. The control device 30 communicates with the smartphone 3 using BLE (Bluetooth Low Energy) (Bluetooth is a registered trademark) and detects the approach of a user when the RSSI (Received Signal Strength Indicator) is above a predetermined threshold. When the control device 30 detects the approach of a user, it sends a trigger signal to the smartphone 3. When the smartphone 3 receives the trigger signal, it periodically sends a request signal to the communication device. The control device 30 may also detect the approach of a user to the vehicle 2 using an ultrasonic sensor or millimeter-wave radar, etc.

[0044] In step S1, the first communication device 10 performs UWB communication with the smartphone 3 and obtains the distances L1A to L1C between the first communication device 10 and the smartphone 3. Also in step S1, the second communication device 20 performs UWB communication with the smartphone 3 and obtains the distances L2A to L2D between the second communication device 20 and the smartphone 3.

[0045] In step S2, the position determination unit 31 determines the provisional position of the smartphone 3 using the three shortest distances from L1A to L1C and L2A to L2D. In step S2, the planar position of the smartphone 3 is determined, not its spatial position. In other words, in step S2, the position of the smartphone 3 is determined in the X and Y directions. In step S2, the three distances used to determine the position of the smartphone 3 are not limited to the three shortest distances from L1A to L1C and L2A to L2D. The position determination unit 31 may use any three distances from L1A to L1C and L2A to L2D.

[0046] In step S3, the region determination unit 32 determines the provisional region to which the smartphone 3 belongs based on the position of the smartphone 3 determined by the position determination unit 31. Specifically, the region determination unit 32 determines which of the pre-set regions A1 to A6 the smartphone 3 belongs to based on the position of the smartphone 3 in the X and Y directions.

[0047] In step S4, the selection unit 33 selects three distances according to the area to which the smartphone 3 belongs. Specifically, the selection unit 33 selects three distances to be used for position determination in step S5, which will be described later, according to the area to which the smartphone 3 belongs, according to the selection table T shown in Figure 5.

[0048] In step S5, the position determination unit 31 determines and updates the position of the smartphone 3 using the three distances selected in step S4. In other words, unlike the position determination in step S2, the position determination in step S5 is performed using the three distances selected by the selection unit 33. Also, unlike the position determination in step S2, the position determination in step S5 determines the position of the smartphone 3 in the X, Y, and Z directions. The control device 30 locks and unlocks the doors of the vehicle 2 by referring to the position of the smartphone 3 determined in step S5.

[0049] In step S6, the region determination unit 32 determines and updates the region to which the smartphone 3 belongs, based on the position of the smartphone 3 determined by the position determination unit 31 in step S5.

[0050] In step S7, the control device 30 determines whether or not the engine (not shown) of vehicle 2 has started. If the control device 30 determines that the engine of vehicle 2 has started, the position determination system 1 terminates the position determination process. If the control device 30 determines that the engine of vehicle 2 has not started, the process proceeds to step S8.

[0051] In step S8, the first communication device 10 performs UWB communication with the smartphone 3, acquires and updates information on the distance L1A to L1C between the first communication device 10 and the smartphone 3. Also in step S8, the second communication device 20 performs UWB communication with the smartphone 3, acquires and updates information on the distance L2A to L2D between the second communication device 20 and the smartphone 3. After that, the position determination process proceeds to step S4.

[0052] The position determination system 1 of this embodiment has the following functions.

[0053] The location determination system 1 can improve the accuracy of location determination by selecting three distances to be used for location determination depending on the area to which the smartphone 3 belongs. For example, if the smartphone 3 is at the location shown in Figure 4, the accuracy of location determination may decrease if the location of the smartphone 3 is determined using the first to third shortest distances L1A, L2A, and L2C out of distances L1A to L1C and L2A to L2D. Specifically, the accuracy of location determination may decrease because the first communication device 10A and the second communication devices 20A and 20C, which acquire distances L1A, L2A, and L2C, are located at approximately the same position in the Y direction. In contrast, in the location determination system of this embodiment, if the smartphone 3 is at the location shown in Figure 4, the location of the smartphone 3 is determined using distances L1B, L2A, and L2C. Since the first communication device 10B, which acquires distance L1B, and the second communication devices 20A and 20C, which acquire distances L2A and L2C, are positioned at different locations in the Y direction, the accuracy of position determination can be improved compared to the case where the position of the smartphone 3 is determined using the first to third shortest distances among distances L1A to L1C and L2A to L2D.

[0054] If the three communication devices used to acquire the three distances for position determination are placed at the same height, the accuracy of position determination may decrease. In contrast, in this embodiment, the first communication device 10 and the second communication device 20 are placed at different positions in the Z direction of the vehicle 2, and the selection unit 33 selects the three distances used for position determination such that at least one of them is acquired by the first communication device 10. This improves the accuracy of position determination compared to the case where the three communication devices used to acquire the three distances for position determination are placed at the same height.

[0055] If the first communication device 10 is surrounded horizontally by metal parts such as the body of the vehicle 2, the UWB radio waves may be shielded by the body when the first communication device 10 communicates with a smartphone 3 located outside the vehicle, which can reduce the accuracy of position determination. In contrast, in this embodiment, the first communication devices 10A and 10B are provided on the left and right front pillars RFP and LFP of the vehicle 2, respectively, and the first communication device 10C is provided on a peripheral member (not shown) located around the rear window RW of the vehicle 2. As a result, when the first communication devices 10A and 10B communicate with a smartphone 3 located outside the vehicle, the UWB radio waves can pass through non-metallic members such as the windshield WS or side window SW, thereby reducing the influence of metal parts of the vehicle body on the accuracy of position determination. Similarly, when the first communication device 10C communicates with a smartphone 3 located outside the vehicle, the UWB radio waves can pass through non-metallic members such as the rear window RW, making it less susceptible to the influence of metal parts such as the body of the vehicle 2. This improves the accuracy of position determination compared to the case where the first communication device 10 is surrounded horizontally by metal parts such as the body of the vehicle 2.

[0056] When determining the position of a smartphone 3 located inside a vehicle using three distances L1A to L1C acquired by the first communication devices 10A to 10C, the accuracy of position determination may decrease if the first communication devices 10A to 10C are located at the same position in the X or Y direction. In contrast, in this embodiment, the first communication devices 10A, 10B and the first communication device 10C are located at different positions in the X direction, and the first communication devices 10A to 10C are located at different positions in the Y direction. Therefore, the accuracy of position determination can be improved compared to the case where the first communication devices 10A to 10C are located at the same position in the X or Y direction.

[0057] When determining the position of a smartphone 3 located inside a vehicle using three distances L1A to L1C acquired by the first communication devices 10A to 10C, the accuracy of position determination may decrease if the first communication devices 10A to 10C are arranged on the same straight line. The first communication devices 10A to 10C are arranged such that when the vehicle 2 is viewed along the Z direction, the lines connecting each of the first communication devices 10A to 10C form a triangle. This improves the accuracy of position determination compared to when the three first communication devices 10 are arranged on the same straight line.

[0058] Although specific embodiments of the present invention have been described above, the present invention is not limited to the above embodiments and can be implemented with various modifications within the scope of this invention.

[0059] The number of first communication devices 10 is not limited to three. The number of first communication devices 10 may be four or more. In this case, it is preferable that the four or more first communication devices 10 include three first communication devices 10 that are positioned at different locations when the vehicle 2 is viewed along the Z direction. It is preferable that at least two of the three first communication devices 10 are positioned at different locations in the X direction. It is preferable that at least two of the three first communication devices 10 are positioned at different locations in the Y direction. Furthermore, it is preferable that the four or more first communication devices 10 include three first communication devices 10 that, when the vehicle 2 is viewed along the Z direction, have lines connecting them forming a triangle.

[0060] The number of second communication devices 20 is not limited to four. [Explanation of Symbols]

[0061] 1. Position determination system 2 vehicles 3. Smartphone (mobile device) 10, 10A~10C First Communications Unit 20, 20A~20D Second communication unit 30 Control device 31 Position determination section 32 Area determination section 33 Selection Section

Claims

1. At least three first communication devices are provided inside the vehicle's interior, which is enclosed by the vehicle's metal body, and each device obtains the distance to a mobile terminal via wireless communication with the mobile terminal located in or around the vehicle. A plurality of second communication devices are provided outside the passenger compartment of the vehicle and each acquires the distance to the mobile terminal, A position determination unit that determines the position of the mobile terminal from the distances acquired by the at least three first communication devices and the plurality of second communication devices, respectively. Equipped with, The aforementioned at least three first communication devices include three first communication devices that are positioned at different locations from one another when viewed along the vehicle height direction. At least two of the three first communication devices are positioned at different locations in the vehicle's longitudinal direction. At least two of the three first communication devices are positioned at different locations in the vehicle width direction. At least two of the aforementioned plurality of second communication devices are arranged at different positions from each other in the vehicle length direction or vehicle width direction. The at least three first communication devices are provided at a position higher than the lower edge of the vehicle's side window, and the plurality of second communication devices are provided at a position lower than the lower edge of the side window. The position determination system is configured such that the position determination unit determines the spatial position of the mobile terminal located outside the vehicle using the distance obtained by a combination of communication devices including at least one of the at least three first communication devices and at least one of the plurality of second communication devices.

2. The position determination system according to claim 1, wherein when viewed along the vehicle height direction, the three straight lines connecting the three first communication devices form a triangle.

3. Two of the three first communication devices are provided on a pair of front pillars of the vehicle, The position determination system according to claim 1 or 2, wherein one of the at least three first communication devices is provided on the rear window or on a peripheral member located around the rear window.

4. A region determination unit determines, based on the position of the mobile terminal determined by the position determination unit, which of a plurality of regions set around the vehicle or inside the vehicle the mobile terminal is located in. A selection unit selects a distance from the distances acquired by the at least three first communication devices and the plurality of second communication devices, according to the region in which the mobile terminal is located, as determined by the region determination unit. Equipped with, The position determination system according to any one of claims 1 to 3, wherein the position determination unit determines the provisional position of the mobile terminal from any distance among the distances acquired by the at least three first communication devices and the plurality of second communication devices, respectively, when no distance has been selected by the selection unit, and determines the position of the mobile terminal from the distance selected by the selection unit when a distance has been selected by the selection unit.

5. The position determination system according to claim 4, wherein the selection unit selects the distance such that it includes at least one of the distances acquired by the at least three first communication devices.

6. The position determination system according to claim 4 or 5, wherein the selection unit selects the distance acquired by the first communication device as having a higher priority than the distance acquired by the second communication device.

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