Communication system and vehicle control device

Abstract

To provide a technique that enables establishment of wireless connection by BLE communication between a vehicle control device and a second portable terminal during establishment of wireless connection by BLE communication between the vehicle control device and a first portable terminal.SOLUTION: The communication system includes a first mobile terminal, a second mobile terminal, and a vehicle control device. The first mobile terminal functions as an electronic key of the vehicle. The second mobile terminal functions as an electronic key of the vehicle. When the first portable terminal has established a BLE connection with each of the vehicle control device and the second portable terminal, the first portable terminal receives, from the second portable terminal, timing information relating to a timing at which the second portable terminal transmits an advertisement signal, and transmits the timing information to the vehicle control device. Based on the timing information received from the first mobile terminal, the vehicle control device transitions to a scan state in which the advertisement signal can be received.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to a technology for performing BLE communication with a mobile terminal that functions as an electronic key for a vehicle. [Background technology]

[0002] In the vehicle control system described in Patent Document 1, a mobile terminal is registered in a vehicle control device as an electronic key for the vehicle, and when the mobile terminal is wirelessly connected to the vehicle control device via BLE communication, the mobile terminal can be used as an electronic key for the vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-96144 Summary of the Invention [Problem to be solved by the invention]

[0004] While a wireless connection via BLE communication is being established between a first portable terminal that is not intended to be used as an electronic key and a vehicle control device, there may be a case where a wireless connection via BLE communication is established between a second portable terminal and a vehicle control device, and the second portable terminal is intended to be used as an electronic key. However, if the transmission interval of the advertising signal of the second portable terminal is relatively long, it is difficult to establish a wireless connection between the second portable terminal and the vehicle control device while a wireless connection between the first portable terminal and the vehicle control device is being established.

[0005] One aspect of the present disclosure provides a technique that enables the establishment of a wireless connection via BLE communication between a vehicle control device and a second mobile terminal while a wireless connection via BLE communication between the vehicle control device and a first mobile terminal is being established. [Means for solving the problem]

[0006] A communication system according to a first aspect of the present disclosure includes a first mobile terminal (20), a second mobile terminal (30), and a vehicle control device (10). The first mobile terminal functions as an electronic key for a vehicle (200). The second mobile terminal functions as the electronic key for the vehicle and is configured to be capable of Bluetooth Low Energy (BLE) communication with the first mobile terminal. The vehicle control device is mounted on the vehicle and is configured to be capable of BLE communication with the first and second mobile terminals. When a wireless connection is established between the first mobile terminal and the vehicle control device via BLE communication, the first mobile terminal transmits a polling signal to the vehicle control device at a first cycle. When a wireless connection is established between the first mobile terminal and the second mobile terminal via BLE communication, the first mobile terminal transmits a polling signal to the second mobile terminal at a second cycle longer than the first cycle. When the first portable terminal establishes a wireless connection with each of the vehicle control device and the second portable terminal via BLE communication, the first portable terminal receives timing information from the second portable terminal regarding the timing at which the second portable terminal transmits an advertising signal, and transmits the timing information to the vehicle control device. The vehicle control device is configured to transition to a scanning state in which it can receive an advertising signal, based on the timing information received from the first portable terminal.

[0007] In the communication system according to the first aspect of the present disclosure, the vehicle control device receives, via the first mobile terminal, the timing at which the second mobile terminal transmits an advertising signal, so that the vehicle control device can transition to a scanning state in accordance with the timing at which the signal is received. This allows a wireless connection between the vehicle control device and the second mobile terminal to be established even if a wireless connection between the vehicle control device and the first mobile terminal has been established first.

[0008] A vehicle control device according to another aspect of the present disclosure is mounted on a vehicle (200) and is capable of Bluetooth Low Energy (BLE) communication with a first portable terminal (20) and a second portable terminal (30) that function as electronic keys for the vehicle. The vehicle control device transmits an advertising signal to the first portable terminal and establishes a wireless connection with the first portable terminal via BLE communication. The vehicle control device receives timing information via the first portable terminal regarding the timing at which the second portable terminal transmits the advertising signal. Based on the received timing information, the vehicle control device transitions to a scanning state in which it can receive an advertising signal transmitted from the second portable terminal.

[0009] A vehicle control device according to a first aspect of the present disclosure can establish a communication connection with a first portable terminal as a slave and receive timing information from the first portable terminal. Furthermore, the vehicle control device can switch to a master role and establish a communication connection with the second portable terminal when an advertising signal is transmitted from the second portable terminal. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a block diagram showing a schematic configuration of a communication system according to a first embodiment. [Figure 2] 1 is a block diagram showing a functional configuration of a communication system according to a first embodiment. [Figure 3] 1 is a diagram showing a configuration of an antenna of a vehicle according to a first embodiment. FIG. [Figure 4] FIG. 10 is a diagram showing the configuration of a vehicle antenna according to a reference example. [Figure 5] 10A and 10B are diagrams illustrating the state in which the ECU and the smartphone, and the smartphone and the key FOB are connected before the ECU and the key FOB are connected in the first embodiment. [Figure 6] 10 is a time chart showing state transitions of the smartphone, the ECU, and the key FOB before the ECU and the smartphone are connected according to the first embodiment. [Figure 7]10 is a time chart of signals transmitted from the smartphone, the ECU, and the key FOB after the ECU and the smartphone are connected according to the first embodiment. [Figure 8] 4 is a flowchart showing a communication process executed by an ECU according to the first embodiment. [Figure 9] 10 is a flowchart showing a communication process executed by the smartphone according to the first embodiment. [Figure 10] 5 is a flowchart showing a communication process executed by a key FOB according to the first embodiment. [Figure 11] FIG. 10 is a diagram illustrating a first key finder function of the smartphone according to the second embodiment. [Figure 12] FIG. 11 is a diagram showing the screen of a smartphone when the smartphone according to the second embodiment is functioning as a key finder. [Figure 13] A figure showing how the key FOB icon displayed on the screen of the smartphone according to the second embodiment changes depending on the position detection accuracy. [Figure 14A] 10 is a flowchart showing a part of a first key search process executed by a smartphone according to a second embodiment. [Figure 14B] 10 is a flowchart showing the rest of the first key search process executed by the smartphone according to the second embodiment. [Figure 15] 10 is a flowchart showing a first communication process executed by a key FOB and an ECU according to a second embodiment. [Figure 16] 10 is a flowchart showing a first communication process executed by a home appliance according to a second embodiment. [Figure 17] FIG. 10 is a diagram illustrating a second key finder function of the smartphone according to the second embodiment. [Figure 18A] 10 is a flowchart showing a part of a second key search process executed by the smartphone according to the second embodiment. [Figure 18B] 10 is a flowchart showing the rest of the second key search process executed by the smartphone according to the second embodiment. [Figure 19]10 is a flowchart showing a second communication process executed by a key FOB according to the second embodiment. [Figure 20] 10 is a flowchart showing a second communication process executed by an ECU according to a second embodiment. [Figure 21] 10 is a flowchart showing second communication processing executed by a home appliance according to a second embodiment. [Figure 22] 10A and 10B are diagrams illustrating learning of the trajectories of the smartphone and key FOB relative to the vehicle in the third embodiment. [Figure 23] FIG. 11 is a diagram illustrating an example of a database of a vehicle according to the third embodiment. [Figure 24] FIG. 10 is a diagram showing the trajectory of the first smartphone according to the third embodiment. [Figure 25] FIG. 11 is a diagram showing a polling period set for the first smartphone according to the third embodiment. [Figure 26] FIG. 11 is a diagram showing the trajectory of the second smartphone according to the third embodiment. [Figure 27] FIG. 11 is a diagram showing a polling period set for a second smartphone according to the third embodiment. [Figure 28] FIG. 10 is a diagram showing the trajectory of a third smartphone according to the third embodiment. [Figure 29] FIG. 11 is a diagram showing a polling period set for a third smartphone according to the third embodiment. [Figure 30A] 10 is a flowchart showing a part of an optimization process executed by an ECU according to a third embodiment. [Figure 30B] 10 is a flowchart showing the rest of the optimization process executed by the ECU according to the third embodiment. [Figure 31] 11 is a flowchart showing a communication process executed by a smartphone according to the third embodiment. [Figure 32] 10 is a flowchart showing a communication process executed by a key FOB according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] [Summary of the embodiment] A second aspect of the present disclosure may provide a technique for adding new functions to a mobile terminal by effectively utilizing the BLE communication function of the FOB key.

[0012] The second aspect of the present disclosure further includes the following items A1 to A9. [Item A1] A processing circuit of the mobile terminal configured to be able to perform BLE communication with each of the key FOB and at least one communication device stationary at a known position, conducting ranging communications with said key FOB and each of said at least one communication device; estimating a distance between the key FOB and each of the at least one communication device based on signal characteristics of the ranging communication; and determining the location of the key FOB based on the estimated distance between each of the at least one communication device and the location of each of the at least one communication device. Key search program.

[0013] [Item A2] the at least one communication device includes a plurality of communication devices; A processing circuit of the mobile terminal, and determining the location of the key FOB based on the location of each of the plurality of communication devices, the estimated distance to the key FOB, and the estimated distance to each of the plurality of communication devices. The key search program described in item A1.

[0014] [Item A3] A processing circuit of the mobile terminal, Repeating the distance measurement communication; repeatedly estimating a distance between the key FOB and each of the at least one communication device based on signal characteristics of each of the repeated ranging communications; and determining the location of the key FOB based on the location of each of the at least one communication device and the repeatedly estimated distance thereto. A key search program according to item A1 or A2.

[0015] [Item A4] A processing circuit of the mobile terminal, communicating with the key fob via BLE using a first key; and performing BLE communication with the at least one communication device using a second key different from the first key. A key search program according to item A1 or A2.

[0016] [Item A5] A processing circuit of the mobile terminal, calculating a likelihood of the identified FOB key location; A key search program according to item A1 or A2.

[0017] [Item A6] the mobile terminal includes a display device; A processing circuit of the mobile terminal, and displaying the position of the key FOB on the display device in a display manner according to the calculated likelihood. A key search program as described in item A5.

[0018] [Item A7] A processing circuit of the mobile terminal, receiving registration of the location of each of the at least one communication device from a user; A key search program according to item A1 or A2.

[0019] [Item A8] the signal characteristics of the ranging signal are a phase and / or a time of flight of the ranging signal; A key search program according to item A1 or A2.

[0020] A third aspect of the present disclosure may provide a technique for adding a new function to a vehicle control device by effectively utilizing the BLE communication functions of the vehicle control device and the mobile terminal. The third aspect of the present disclosure further includes the following items B1 to B7.

[0021] [Item B1] a vehicle control device mounted on the vehicle; At least one first mobile terminal carried by a specific user, functioning as an electronic key for the vehicle, and configured to be capable of BLE communication with the vehicle control device; the at least one first mobile terminal is configured to transmit a polling signal at a first polling period when a wireless connection with the vehicle control device is established through the BLE communication; The vehicle control device includes: calculating a position of the vehicle and a movement trajectory of each of the at least one first mobile terminal relative to the vehicle; learning the movement trajectory calculated so far for each first identification information identifying each of the at least one first mobile terminal and each position of the vehicle; storing learned data of the movement trajectory of each of the at least one first mobile terminal in association with the first identification information and the position of the vehicle; and determining the first polling period of the first mobile terminal corresponding to the first identification information at the vehicle location based on the vehicle location, the first identification information, and the learning data. Communication system.

[0022] [Item B2] the vehicle is equipped with a plurality of antennas; The vehicle control device includes: repeatedly performing ranging communication with the at least one first mobile terminal via each of the plurality of antennas; each time the distance measurement communication is performed, a relative position of the at least one first mobile terminal with respect to the vehicle is acquired based on a distance measurement result obtained by each of the plurality of antennas; calculating the movement trajectory of the at least one first portable terminal relative to the vehicle from the relative positions acquired in each of the repeated distance measurement communications; The calculated movement trajectory is stored in association with the first identification information and the position of the vehicle. Item B1. The communication system according to item B1.

[0023] [Item B3] the storage unit stores the learning data further linked to a time, the vehicle control device is configured to determine the first polling period of the first mobile terminal corresponding to the first identification information at the time and the vehicle position, based on the time, the position of the vehicle, the first identification information, and the learning data. The communication system according to item B2.

[0024] [Item B4] The vehicle control device further includes a second mobile terminal that is shared by a user of the at least one first mobile terminal, functions as an electronic key for the vehicle, and is configured to be able to communicate with the vehicle control device via the BLE. the second mobile terminal is configured to transmit a polling signal at a second polling period when a wireless connection with the vehicle control device is established through the BLE communication; The vehicle control device includes: calculating a movement trajectory of the second mobile device relative to the position of the vehicle; and determining the second polling period based on the position of the vehicle, the calculated movement trajectory of the second mobile terminal, and the stored learning data. The communication system according to item B1 or B2.

[0025] [Item B5] The vehicle control device includes: comparing the movement trajectory of the second mobile terminal with the learning data to estimate the user of the second mobile terminal from among the users of the at least one mobile terminal; determining the second polling period at the vehicle location based on the vehicle location, the first identification information corresponding to the estimated user, and the learning data; A communication system according to item B4.

[0026] [Item B6] The vehicle control device is configured to store a movement trajectory of the second mobile terminal in association with the first identification information corresponding to the estimated user. The communication system according to item B5.

[0027] [Item B7] the vehicle control device is configured to transmit the determined second polling period to the second mobile terminal. A communication system according to item B4.

[0028] Specific Exemplary Embodiments (1. First embodiment) <1-1.Configuration> The configuration of a communication system 100 according to this embodiment will be described with reference to Figure 1. The communication system 100 includes a digital key ECU 10, a smartphone (hereinafter referred to as "smartphone") 20, a key FOB 30, a first home appliance 40, a second home appliance 50, a third home appliance 60, two Bluetooth Low Energy (hereinafter referred to as "BLE") antennas 70, and four ultra-wideband wireless communication (hereinafter referred to as "UWB communication") / BLE antennas 95. In this embodiment, it is assumed that the smartphone 20 has the function of a digital key for a vehicle 200, and that both the smartphone 20 and the FOB key 30 are used as the digital key for the vehicle 200.

[0029] The Digi-Key ECU 10 is mounted on the vehicle 200 and is connected to multiple BLE antennas 70 and a UWB / BLE antenna 95 of the vehicle 200 via communication lines conforming to the CAN (registered trademark) or CAN FD communication protocol. The Digi-Key ECU 10 includes a CPU, ROM, RAM, I / O, etc., and performs BLE communication via the BLE antenna 70. The Digi-Key ECU 10 manages a digital key for the vehicle 200. The digital key for the vehicle 200 is used to unlock or lock the doors or trunk of the vehicle 200. The digital key for the vehicle 200 is also used to start or stop the engine. The functions of the digital key for the vehicle 200 can be restricted depending on the user's authority. For example, the digital key for the vehicle 200 can be set to only be able to unlock or lock the vehicle 200, or can be used only for a specific period of time.

[0030] The digital key ECU 10 also realizes a passive entry / passive start (hereinafter referred to as PEPS) function. PEPS is a function that automatically unlocks the doors or trunk when a user carrying a digital key or smart key for the vehicle 200 approaches the vehicle 200, and automatically locks the doors or trunk when the user leaves the vehicle 200.

[0031] The smartphone 20 includes a CPU, ROM, RAM, I / O, a wireless communication device, etc., and functions as a digital key for the vehicle 200 by executing a predetermined application program. The smartphone 20 performs BLE communication with the digital key ECU 10 via a BLE antenna 70 or a UWB / BLE antenna 95. The smartphone 20 also performs BLE communication with the key FOB 30 and the first, second, and third home appliances 40, 50, and 60. The smartphone 20 may also perform ultra-wideband wireless communication (hereinafter, UWB communication) with the digital key ECU 10. In this embodiment, the smartphone 20 corresponds to the first mobile terminal of the present disclosure. In another embodiment, the first mobile terminal is not limited to a smartphone, and may be a mobile terminal such as a tablet terminal or a wearable device.

[0032] The key FOB 30 is a key holder-type smart key that supports BLE communication and has a built-in wireless communication device. The key FOB 30 is used to unlock or lock the doors or trunk of the vehicle 200, as well as to start or stop the engine. The key FOB 30 performs BLE communication with the digital key ECU 10 via the BLE antenna 70 or the UWB / BLE antenna 95. The key FOB 30 also performs BLE communication with the smartphone 20 and the first, second, and third home appliances 40, 50, and 60. The key FOB 30 may also perform UWB communication with the digital key ECU 10. In this embodiment, the key FOB 30 corresponds to the second mobile terminal of the present disclosure.

[0033] The first, second, and third home appliances 40, 50, and 60 are BLE communication-compatible home appliances with built-in wireless communication devices, such as air conditioners, refrigerators, and televisions. The first, second, and third home appliances 40, 50, and 60 are fixed in predetermined positions. The first, second, and third home appliances 40, 50, and 60 communicate with the smartphone 20 and the key FOB 30 via BLE, respectively.

[0034] As shown in FIG. 3 , two BLE antennas 70 are disposed near the center of the vehicle 200 and transmit and receive BLE signals. Four UWB / BLE antennas 95 are disposed at the front left end, front right end, rear left end, and rear right end of the vehicle 200 and transmit and receive UWB signals or BLE signals. In another embodiment, the vehicle may be equipped with only one of the two BLE antennas 70, or three or more BLE antennas 70. Furthermore, the vehicle may be equipped with three or fewer UWB / BLE antennas 95, or five or more UWB / BLE antennas 95. In this embodiment, the UWB / BLE antenna 95 transmits and receives BLE signals. In this embodiment, the Digi-Key ECU 10 and the BLE antenna 70 or the UWB / BLE antenna 95 correspond to a vehicle control device for the vehicle 200 of the present disclosure. In another embodiment, the Digi-Key ECU 10 may have a built-in BLE antenna 70.

[0035] In the vehicle 200, both the smartphone 20 and the key FOB 30 communicate with the digital key ECU 10 via BLE, and the digital key ECU 10 controls the functions of both the digital key system and the PEPS system. In other words, the digital key system and the PEPS system are integrated in the vehicle 200.

[0036] On the other hand, as shown in FIG. 4, a conventional vehicle 205 is equipped with a digital key ECU 15 that controls a digital key system and a PEPSECU 16 that controls a PEPS system, but the digital key system and the PEPS system are not integrated. The digital key ECU 15 is connected to multiple BLE antennas 70 and multiple UWB antennas 95. The PEPSECU 16 is connected to multiple Low Frequency (hereinafter, LF) antennas 75. The smartphone 20 performs BLE communication or UWB communication with the digital key ECU 15 via the BLE antenna 70 or the UWB antenna 95. The key FOB 30 performs LF communication or Radio Frequency (hereinafter, RF) communication with the PEPSECU 16 via the LF antenna 75.

[0037] In vehicle 200, the key FOB 30 performs BLE communication with the digital key ECU 10, similar to the smartphone 20, thereby integrating the digital key system and the PEPS system. As a result, vehicle 200 is not equipped with an LF antenna 75. In other words, compared to vehicle 205, vehicle 200 can eliminate the LF / RF system.

[0038] Next, the functions of each device included in the communication system 100 will be described with reference to FIG. The smartphone 20 has the functions of a BLE transmitter 21, a BLE receiver 22, a secure memory 23, and a timing buffer 24, and measures a first distance D1 and a second distance D2. The first distance D1 is the distance from the smartphone 20 to the vehicle 200, and the second distance D4 is the distance from the smartphone 20 to the key FOB 30.

[0039] The timing buffer 24 stores timing information, which will be described later. The secure memory 23 stores a car digital key, a key FOB digital key, a key finder digital key A, and a key finder digital key B. The car digital key is used for BLE communication with the digi-key ECU 10 when the smartphone 20 functions as a digital key for the vehicle 200. The key FOB digital key is used for BLE communication with the key FOB 30 when the smartphone 20 functions as a digital key for the vehicle 200. The key finder digital key A is shared with the digi-key ECU 10 and the key FOB 30 when the smartphone 20 functions as a key finder, which will be described later. The key finder digital key B is shared with one or more or two or more of the first, second, and third home appliances 40, 50, and 60 when the smartphone 20 functions as a key finder.

[0040] The key FOB 30 has the functions of a BLE transmitter 31, a BLE receiver 32, and a secure memory 33, and measures a third distance D3. The third distance D3 is the distance from the key FOB 30 to the vehicle 200.

[0041] The secure memory 33 stores a vehicle digital key, a key finder digital key A, and a key finder digital key B, which are used for BLE communication with the digital key ECU 10.

[0042] The first home appliance 40 has the functions of a BLE transmitter 41, a BLE receiver 42, and a memory 43. The memory 43 stores a digital key B for a key finder.

[0043] The BLE antenna 70 has the functions of a BLE transmitter 71, a BLE receiver 72, and a CAN driver 73. The BLE antenna 70 functions as a master when communicating with the key FOB 30, and functions as a slave when communicating with the smartphone 20. When multiple BLE antennas 70 function as masters, the multiple BLE antennas 70 establish wireless connections via BLE communication with the key FOB 30 in turn. Furthermore, any one of the multiple BLE antennas 70 may monitor packets flowing through the CAN network of the vehicle 200 when another BLE antenna 70 establishes a wireless connection with the key FOB 30.

[0044] The Digi-Key ECU 10 includes the functions of a DB 11, a secure memory 12, a registration information memory 13, and a CAN driver 14. The Digi-Key ECU 10 measures the first distance D1 and the third distance D3 via the BLE antenna 70.

[0045] DB11 stores the model of smartphone 20, the position of vehicle 200, the time when the position of vehicle 200 was acquired, and the movement trajectory of smartphone 20. The position of vehicle 200 is calculated based on a GPS signal received by GPS receiver 81. The time is received from clock 82.

[0046] The secure memory 12 stores a smartphone digital key, a key FOB digital key, and a key finder digital key A. The registration information memory 13 registers identification information of devices that have established a wireless connection with the digital key ECU 10 via BLE communication.

[0047] <1-2. Overview of BLE communication> In this embodiment, the smartphone 20 and the digital key ECU 10, the smartphone 20 and the key FOB 30, and the digital key ECU 10 and the key FOB 30 each perform BLE communication using a master-slave method. In BLE communication, the master detects signals intermittently transmitted by the slave, and if the signal is from the slave to be connected, it requests a connection from the slave. The master controls the timing of data transmission and reception. In BLE communication, the communication band is divided into channels 0 to 36 and channels 37 to 39. Channels 37 to 39 are used to search for and connect to devices, and channels 0 to 36 are used for communication between devices once a connection has been established.

[0048] FIG. 6 shows a time chart of each state before a wireless connection is established between the digital key ECU 10, smartphone 20, and key FOB 30. The smartphone 20 is fixed to the role of master and transitions to a scanning state for a predetermined period at period T1. The smartphone 20 enters a scanning state in which it receives an advertising signal on one of channels 37 to 39 at each period, and switches between channels 37 to 39 in sequence. Because scanning consumes a lot of power, the smartphone 20, which can be easily charged by the user, is fixed to the role of master.

[0049] When the smartphone 20 receives the advertising signal from the digital key ECU 10, it acquires information about the digital key ECU 10 from the digital key ECU 10 and requests a connection to the digital key ECU 10. The smartphone 20 then establishes a wireless connection with the digital key ECU 10 and transmits a polling signal to the digital key ECU 10 at a first polling cycle corresponding to the digital key ECU 10. The polling signal is a protocol data unit (hereinafter referred to as PDU).

[0050] When the smartphone 20 receives an advertising signal from the key FOB30, it acquires information about the key FOB30 from the key FOB30 and requests a connection to the key FOB30. Then, the smartphone 20 establishes a wireless connection with the key FOB30, and the smartphone 20 transmits a polling signal to the key FOB30 at a second polling period corresponding to the key FOB30. Because the battery capacity of the key FOB30 is relatively small, the second polling period is longer than the first polling period to suppress power consumption of the key FOB30.

[0051] Key FOB30 is fixed to the role of slave and transmits advertising signals at period T3. Key FOB30 transmits advertising signals on channels 37 to 39 every period. Period T3 is longer than period T1 and period T2, which will be described later. The advertising side operates with lower power consumption than the scanning side. Therefore, key FOB30, which has a relatively small battery capacity, is fixed to the role of slave and transmits advertising signals at long intervals in order to reduce power consumption.

[0052] The digital key ECU 10 acts as a slave to the smartphone 20 and as a master to the key FOB 30. The digital key ECU 10 transmits advertising signals and scan signals at a period T2. The period T2 is shorter than the period T1. Each period includes a period for transmitting advertising signals on channels 37 to 39 and a scan period for the advertising signals on one of channels 37 to 39. The digital key ECU 10 alternates between channels 37 to 39 during the scan period. The digital key ECU 10 switches between the roles of slave and master during one period. The scan period of the digital key ECU 10 is shorter than the scan period of the smartphone 20.

[0053] When the digital key ECU 10 receives the advertising signal from the key FOB 30, it acquires information about the key FOB 30 from the key FOB 30 and requests a connection to the key FOB 30. The digital key ECU 10 then establishes a wireless connection with the key FOB 30 and transmits a PDU to the key FOB 30 at the second polling period corresponding to the key FOB 30.

[0054] The channel spacing of the advertising signals transmitted from the key FOB 30 is set so that the transmission period of the advertising signals of the three channels transmitted from the key FOB 30 is longer than the period when the digital key ECU 10 is not scanning. In other words, the channel spacing of the advertising signals is set so that the advertising signal of at least one channel transmitted from the key FOB 30 overlaps with the scanning period of the digital key ECU 10.

[0055] After the digital key ECU 10 and smartphone 20 establish a wireless connection, the key FOB 30 may attempt to establish a wireless connection with the digital key ECU 10. For example, as shown in Figure 5, when person A, who has no plans to use the vehicle 200, approaches the vehicle 200 carrying the smartphone 20 and enters the communication range of the digital key ECU 10, a wireless connection is established between the smartphone 20 and the digital key ECU 10. When person B approaches the vehicle 200 carrying the key FOB 30 to use the vehicle 200, the key FOB 30 attempts to establish a wireless connection with the smartphone 20 and the digital key ECU 10.

[0056] Once a wireless connection between the smartphone 20 and the digital key ECU 10 is established, the smartphone 20 and the digital key ECU 10 perform scanning between communications. The key FOB 30 transmits advertising signals at a relatively long period T3 to reduce power consumption. Because the scanning period of the smartphone 20 is relatively long, establishing a wireless connection between the smartphone 20 and the key FOB 30 is relatively easy. However, because the scanning period of the digital key ECU 10 is relatively short, the scanning period of the digital key ECU 10 does not easily coincide with the period during which the advertising signal is transmitted from the key FOB 30. Consequently, establishing a wireless connection between the digital key ECU 10 and the key FOB 30 can take a significant amount of time.

[0057] Therefore, in this embodiment, the smartphone 20, which has established a wireless connection with each of the digital key ECU 10 and the key FOB 30, receives timing information from the key FOB 30 and transmits the received timing information to the digital key ECU 10. The timing information is information regarding the timing at which the key FOB 30 transmits an advertising signal. Based on the timing information received from the smartphone 20, the digital key ECU 10 transitions to a scanning state to coincide with the timing at which the advertising signal is transmitted from the key FOB 30. This establishes a wireless connection between the digital key ECU 10 and the key FOB 30, allowing the key FOB 30 to execute PEPS. Details of the communication process between the digital key ECU 10, smartphone 20, and key FOB 30 will be described later.

[0058] <1-3. Processing> <1-3-1. Communication processing performed by the Digi-Key ECU> The communication process executed by the digital key ECU 10 will be described with reference to the flowchart in Figure 8. The digital key ECU 10 starts this process when the smartphone 20 enters the communication range of the digital key ECU 10, and repeatedly executes this process.

[0059] In S10, the digital key ECU 10 establishes a wireless connection via BLE communication with the smartphone 20. As shown in Fig. 7, the digital key ECU 10 receives a polling signal from the smartphone 20 at a first polling period (i.e., T10 ms).

[0060] Next, in S20, the digital key ECU 10 measures a first distance D1 between the smartphone 20 and the vehicle 200 through BLE Channel Sounding (hereinafter, BLE CS) communication with the smartphone 20. More specifically, as shown in FIG. 7 , the digital key ECU 10 receives a ranging signal transmitted as a polling signal from the smartphone 20. The ranging signal includes a Continuous Wave (hereinafter, CW) signal and a Round Trip Time (hereinafter, RTT) signal. The RTT signal includes a first time stamp indicating the time when the smartphone 20 transmitted the RTT signal.

[0061] The digital key ECU 10 calculates a first distance D1 (hereinafter referred to as the first distance D1cw) based on the phase of the CW signal and transmits the received CW signal back to the smartphone 20. The digital key ECU 10 also adds a second timestamp indicating the time the RTT signal was received to the RTT signal. The digital key ECU 10 also adds a third timestamp indicating the time the digital key ECU 10 transmits the RTT signal, and transmits the RTT signal to the smartphone 20.

[0062] The smartphone 20 calculates the flight time of the RTT signal between the smartphone 20 and the vehicle 200 based on the first to third timestamps and the time when the smartphone 20 received the RTT signal. Furthermore, the smartphone 20 calculates a first distance D1 (hereinafter, first distance D1rtt) based on the calculated flight time, and transmits the calculated first distance D1rtt to the digital key ECU 10.

[0063] The first distance D1cw has higher accuracy than the first distance D1rtt. For example, the ranging error of the first distance D1cw is less than ±30 cm, while the ranging error of the first distance D1rtt is several meters. However, when calculating the distance based on the CW signal, the distance cannot be determined uniquely if the phase difference exceeds 2π. Therefore, when measuring the distance based on the CW signal, there is an upper limit to the measurable range. On the other hand, when measuring the distance based on the RTT signal, there is no limit to the measurable range. Therefore, by combining the CW signal and the RTT signal, the distance measured by the CW signal is used preferentially within the measurable range of the CW signal, and the distance measured by the RTT signal is used outside the measurable range of the CW signal.

[0064] Next, in S30, the digital key ECU 10 determines whether the first distance D1 is equal to or greater than a distance threshold. For example, the distance threshold is 10 m. If the digital key ECU 10 determines that the first distance D1 is less than the distance threshold, the digital key ECU 10 prioritizes a wireless connection with the smartphone 20 and does not establish a wireless connection with the key FOB 30. In other words, the digital key ECU 10 maintains an unestablished wireless connection with the key FOB 30. Therefore, if the digital key ECU 10 determines that the first distance D1 is less than the distance threshold, the digital key ECU 10 terminates this process. If the smartphone 20 is relatively close to the vehicle 200, the digital key ECU 10 prioritizes BLE communication with the smartphone 20 because the smartphone 20 is likely to be used as a digital key for the vehicle 200 and the key FOB 30 is unlikely to be used. If the digital key ECU 10 determines that the first distance D1 is equal to or greater than the distance threshold, the digital key ECU 10 proceeds to S40.

[0065] In S40, the digital key ECU 10 receives timing information of the key FOB 30 and the second distance D2 from the smartphone 20. As shown in Figure 7, the timing information indicates the time from the current time until the advertising signal is transmitted (i.e., T20-T30 ms).

[0066] In S50, the digital key ECU 10 executes the same process as in S20 because the smartphone 20 may have moved. Next, in S60, the digital key ECU 10 executes the same process as in S30. If it is determined in S60 that the first distance D1 is less than the distance threshold, the process ends, but if it is determined that the first distance D1 is equal to or greater than the distance threshold, the process proceeds to S70.

[0067] In step S70, the digital key ECU 10 transitions to a scanning state and executes a scan in accordance with the timing information received in step S40 when the key fob 30 transmits an advertising signal. That is, as shown in Figure 7, the digital key ECU 10 cuts off the wireless connection with the smartphone 20 and enters a scanning state when the key fob 30 transmits an advertising signal.

[0068] Next, in S80, the digital key ECU 10 determines whether or not an advertising signal has been received from the key FOB 30. If it is determined that an advertising signal has not been received, the process ends, but if it is determined that an advertising signal has been received, the process proceeds to S90.

[0069] In the S90, the digital key ECU 10 establishes a wireless connection with the key FOB 30 via BLE communication. In S100, the digital key ECU 10 measures the third distance D3 through BLE CS communication with the key FOB 30. Specifically, as shown in FIG. 7 , the digital key ECU 10 transmits a CW signal to the key FOB 30 and calculates the third distance D3 (hereinafter referred to as the third distance D3cw) based on the phase of the CW signal returned from the key FOB 30.

[0070] The digital key ECU 10 also transmits an RTT signal with a first timestamp added to it to the key FOB 30, and receives the RTT signal returned from the key FOB 30. The digital key ECU 10 then calculates a third distance D3 (hereinafter, the third distance D3rtt) based on the time at which the RTT signal was received and the first to third timestamps added to the RTT signal, and transmits the calculated third distance D3rtt to the key FOB 30.

[0071] Next, in S110, the wireless connection for BLE communication with the key FOB 30 is cut off, and this process ends.

[0072] <1-3-2. Communication processing performed by smartphones> The communication process executed by the smartphone 20 will be described with reference to the flowchart of Figure 9. The smartphone 20 starts this process when the digital key ECU 10 enters the communication range of the smartphone 20, and repeatedly executes this process.

[0073] In S120, the smartphone 20 establishes a wireless connection via BLE communication with the digital-key ECU 10. The smartphone 20 transmits a polling signal to the digital-key ECU 10 at a first polling period.

[0074] Next, in S130, the smartphone 20 measures the first distance D1 through BLE CS communication with the digital key ECU 10. More specifically, the smartphone 20 transmits a CW signal to the digital key ECU 10 and calculates the first distance D1cw based on the phase of the CW signal returned from the digital key ECU 10.

[0075] The smartphone 20 also transmits an RTT signal with a first timestamp added to the digital key ECU 10 and receives the RTT signal returned from the digital key ECU 10. The smartphone 20 then calculates a first distance D1rtt based on the time the RTT was received and the first to third timestamps, and transmits the calculated first distance D1rttt to the digital key ECU 10.

[0076] Next, in S140, the smartphone 20 determines whether the first distance D1 is equal to or greater than the distance threshold. If it is determined that the first distance D1 is less than the distance threshold, the smartphone 20 terminates this process to prevent the establishment of a wireless connection between the digital key ECU 10 and the key FOB 30. If it is determined that the first distance D1 is equal to or greater than the distance threshold, the smartphone 20 proceeds to S150.

[0077] In S150, the smartphone 20 establishes a wireless connection via BLE communication with the key FOB 30 and performs BLE communication. The smartphone 20 transmits a polling signal to the key FOB 30 at a second polling period. The second polling period is longer than the first polling period.

[0078] Next, in S160, the smartphone 20 requests timing information regarding the timing of transmitting the advertisement signal from the key FOB 30 via BLE communication, and confirms the timing of transmitting the advertisement signal from the key FOB 30 to the digital key ECU 10. In detail, as shown in FIG. 7, the smartphone 20 receives a notification that the timing of transmitting the advertisement signal from the key FOB 30 is T20 ms from the current time.

[0079] Next, in S170, the smartphone 20 performs BLE communication with the digital key ECU 10. Next, in S180, the smartphone 20 transmits timing information regarding the timing of transmitting the advertising signal and the second distance D2 measured by the BLE CS communication to the digital-key ECU 10 via BLE communication. As shown in FIG. 7, the smartphone 20 notifies the digital-key ECU 10 of the time T20 ms received from the key FOB 30 minus the elapsed time T30 ms from the time of S160 to the present time (T20-T30 ms).

[0080] Next, in S190, the smartphone 20 measures the first distance D1 through BLE CS communication with the digital key ECU 10, and then ends this process.

[0081] <1-3-3. Communication process performed by key FOB> The communication process executed by the key FOB 30 will be described with reference to the flowchart of Fig. 10. When the key FOB 30 enters the communication range of the smartphone 20, the key FOB 30 starts this process and repeatedly executes this process.

[0082] In the S200, the key FOB 30 establishes a wireless connection with the smartphone 20 via BLE communication. Next, in S210, the key FOB 30 transmits to the smartphone 20 via BLE communication the timing for transmitting an advertising signal to the digital key ECU 10.

[0083] Next, in S220, the key fob 30 transmits an advertising signal to the digital key ECU 10 at the same timing as the signal transmitted in S200. Next, in S230, the key fob 30 determines whether or not a connection request has been received from the digital key ECU 10. If it is determined that a connection request has been received from the digital key ECU 10, the process proceeds to S240, and if it is determined that a connection request has not been received, the process ends.

[0084] In step S240, the key FOB 30 establishes a wireless connection with the digital key ECU 10 via BLE communication. Next, in S250, the key FOB 30 measures the third distance D3 through BLE CS communication with the digital key ECU 10. Specifically, the key FOB 30 calculates the third distance D3cw based on the phase of the CW signal received from the digital key ECU 10 and transmits the received CW signal to the digital key ECU 10. The key FOB 30 also adds second and third timestamps to the RTT signal received from the digital key ECU 10 and transmits the RTT signal to the digital key ECU 10. The key FOB 30 then receives the calculated third distance D3rtt from the digital key ECU 10.

[0085] Next, in S260, the key FOB 30 disconnects the wireless connection with the digital key ECU 10 via BLE communication, and this process ends.

[0086] <1-4. Effects> According to the first embodiment described above in detail, the following effects are achieved.

[0087] (1-1) In the communication system 100, the digital key ECU 10 receives the timing when the key FOB 30 transmits an advertising signal via the smartphone 20. Therefore, the digital key ECU 10 can transition to a scanning state in accordance with the received timing. This allows the digital key ECU 10 to establish a wireless connection via BLE communication between the digital key ECU 10 and the key FOB 30 even if a wireless connection via BLE communication between the digital key ECU 10 and the smartphone 20 has already been established.

[0088] (1-2) When the smartphone 20 is located near the vehicle 200, the digital key ECU 10 can prioritize BLE communication with the smartphone 20 by not establishing a wireless connection with the key FOB 30 via BLE communication.

[0089] (1-3) The smartphone 20 and the digital key ECU 10 can measure the distance D1 between the smartphone 20 and the vehicle 200 based on the signal characteristics of the BLE communication. (1-4) The smartphone 20 and the Digi-Key ECU 10 can measure the first distance D1cw with high accuracy within a limited range based on the phase of the CW signal. Furthermore, the smartphone 20 and the Digi-Key ECU 10 can measure the first distance D1rtt without any limitations on the measurable range based on the time of flight of the Rtt signal. By combining two distance measurement methods, the smartphone 20 and the Digi-Key ECU 10 can measure the first distance D1 with high accuracy when the smartphone 20 is close to the vehicle 200. Furthermore, the smartphone 20 and the Digi-Key ECU 10 can measure the first distance D1 with lower accuracy when the smartphone 20 is far from the vehicle 200.

[0090] (1-5) The smartphone 20 and the key FOB 30 can measure the distance D2 between the smartphone 20 and the key FOB 30 based on the signal characteristics of the BLE communication. (1-6) The smartphone 20 and the key FOB 30 can measure the second distance D2cw with high accuracy within a limited range based on the phase of the CW signal. Also, the smartphone 20 and the key FOB 30 can measure the second distance D1rtt without any limit on the measurable range based on the time of flight of the Rtt signal.

[0091] (1-7) The digital key ECU 10 can establish a wireless connection via BLE communication with the smartphone 20 as a slave and receive timing information of the key FOB 30 from the smartphone 20. Furthermore, based on the received timing information, the digital key ECU 10 can switch to a master role and establish a wireless connection via BLE communication with the key FOB 30 when an advertising signal is transmitted from the key FOB 30.

[0092] (2. Second Embodiment) <2-1. Smartphone key finder function> The second embodiment has the same basic configuration as the first embodiment, so differences will be described below. Note that the same reference numerals as those in the first embodiment indicate the same configuration, and reference will be made to the preceding description.

[0093] In the second embodiment, the BLE communication function of the key FOB 30 is effectively utilized to add a finder function to the smartphone 20. With distance measurement using BLE CS, even if the key FOB 30 is located in a position where it cannot directly receive a signal from the smartphone 20, the signal is easily transmitted and received by bypassing the route compared to UWB. Furthermore, while it is difficult to measure distance with high accuracy using Wi-Fi (registered trademark), distance measurement using BLE CS can measure distance with high accuracy by separating signals that are less affected by multipath based on the phase difference of multiple frequencies. Therefore, by adding a finder function to the smartphone 20, it is possible to use the BLE communication function to search for the key FOB 30 when it is lost.

[0094] By adding a finder function to the smartphone 20, the smartphone 20 can be used to search for BLE devices having a BLE communication function in addition to the key FOB 30. Examples of mobile devices having a BLE communication function include wireless earphones.

[0095] <2-2. Processing> <2-2A. First Example> In the first embodiment, the smartphone 20 is fixed as the master, and two or more communication devices and the key FOB 30 are fixed as slaves. The communication devices are stationary (i.e., their positions are constant) and have BLE communication capabilities. In this embodiment, the communication devices are two or more of the digital key ECU 10, the first home appliance (specifically, an air conditioner) 40, and the second home appliance (specifically, a slave) 50. In the first embodiment, the position of the smartphone 20 is changed, and the distance from the smartphone 20 to each of the two or more communication devices and the key FOB 30 is measured multiple times to identify the position of the key FOB 30.

[0096] <2-2A-1. First key search process executed by smartphone> The first key search process executed by the smartphone 20 will be described with reference to the flowcharts of FIGS. 14A and 14B.

[0097] In the S300, a key finder application is started by a user operation. In step S310, the ID and password input by the user are accepted. The smartphone 20 may request the ID and password only when the user first launches the key finder app, and may not need to request them every time.

[0098] Next, in S320, the smartphone 20 generates digital keys A and B from the ID and password. Next, in S330, the smartphone 20 transmits the digital key A to the digital key ECU 10 and the key FOB 30 via BLE communication, and shares the digital key A. The digital key A is used for BLE communication with the digital key ECU 10 and the key FOB 30. The digital key ECU 10 and the key FOB 30 store the received digital key A in the secure memories 12 and 33, so the smartphone 20 only needs to transmit the digital key A when it first generates the digital key A.

[0099] Next, in S340, the smartphone 20 transmits the digital key B to the first and second home appliances 40, 50 via BLE communication, and shares the digital key B. The digital key B is used for BLE communication with the first and second home appliances 40, 50. By changing the digital key shared between the smartphone 20 and the first and second home appliances 40, 50 to the digital key shared between the smartphone 20 and the digital key ECU 10 and the key FOB 30, the security of the vehicle 200 is strengthened. In this embodiment, as shown in FIG. 11 , the smartphone 20 establishes a wireless connection with the air conditioner 40 and the television 50 via BLE communication, and transmits the digital key B to the air conditioner 40 and the television 50. The air conditioner 40 and the television 50 store the received digital key in memory 43, so the smartphone 20 only needs to transmit the digital key B when it first generates the digital key B.

[0100] Next, in S350, the smartphone 20 displays communication devices other than the key FOB 30 that are wirelessly connected via BLE communication on the screen of the smartphone 20. The communication devices other than the key FOB 30 are either the fixed first and second home appliances 40 and 50, or the digital key ECU 10 of the parked vehicle 200. In this embodiment, the communication devices other than the key FOB 30 are two or more of the digital key ECU 10, the air conditioner 40, and the television 50. For example, as shown in FIG. 12 , the smartphone 20 displays icons of the air conditioner 40 and the television 50 on the screen of the smartphone 20.

[0101] Next, in S360, the smartphone 20 prompts the user to place icons of two or more communication devices that are wirelessly connected via BLE communication on the GUI on the screen. For example, as shown in FIG. 12, the smartphone 20 prompts the user to place the icons of the air conditioner 40 and the television 50 on the image of the room on the screen so that they correspond to their actual installation positions in the room. This determines the position (x1, y1) of the air conditioner 40 and the position (x2, y2) of the television 50 on the app, as shown in FIG. 11.

[0102] Next, in S370, the smartphone 20 determines whether the communication devices wirelessly connected via BLE communication include a communication device located within the error range of distance measurement by BLE CS. That is, the smartphone 20 determines whether there is a communication device approximately adjacent to the smartphone 20. If it is determined that there is no communication device approximately adjacent to the smartphone 20, the process proceeds to S390. If it is determined that there is a communication device approximately adjacent to the smartphone 20, the process proceeds to S380.

[0103] In S380, the smartphone 20 warns the user that the smartphone 20 is too close to the communication device, urges the user to move away from the communication device, and returns to the processing of S370. In S390, the smartphone 20 measures the distance to the communication device placed on the GUI through BLE CS communication. For example, as shown in FIG. 11 , the smartphone 20 measures a distance d1a to the air conditioner 40 and a distance d2a to the television 50.

[0104] Next, in S400, the smartphone 20 specifies the position of the smartphone 20 on the GUI. For example, the smartphone 20 specifies the position of the smartphone 20 relative to the air conditioner 40 and the television 50 based on the distances d1a and d2a.

[0105] Next, in S410, the smartphone 20 determines whether the smartphone 20 is in the correct room based on the position of the smartphone 20 identified in S400. The correct room may be the room where the air conditioner 40 and the television 50 are located, or the parking lot where the vehicle 200 is parked. If it is determined that the smartphone 20 is in the correct room, the process proceeds to S420. If it is determined that the smartphone 20 is not in the correct room, the measurement of the distance d1a or d2a may be incorrect, so the process returns to S390.

[0106] In S420, the smartphone 20 measures the distance d3a to the key FOB 30 via BLE CS communication. Next, in S430, the smartphone 20 updates the number of times n to n + 1. The initial value of n is 0.

[0107] Next, in S440, the smartphone 20 determines whether the number of times n is 2 or more. The position of the key FOB 30 is identified by moving the position of the smartphone 20 and repeating the processes of S390 to S420 two or more times. Therefore, as shown in Fig. 12, if it is determined that the number of times n is 1 or less, the user is prompted to move the smartphone 20, and the process returns to S390. If it is determined that the number of times n is 2 or more, the process proceeds to S450.

[0108] In S450, as shown in FIG. 11, the smartphone 20 determines the location of the key FOB 30 based on the past location of the smartphone 20, the distance d3a to the key FOB 30 measured at the past location, and the current location of the smartphone 20 and the distance d3b to the key FOB 30 measured at the current location. When the number of times n is 2, two location candidates are calculated as the location of the key FOB 30. The smartphone 20 determines one of the two location candidates as the location of the key FOB 30 depending on whether the location candidate is located within the room. Alternatively, the smartphone 20 may further repeat the processes of S390 to S420. By further repeating the processes of S390 to S420, the location of the key FOB 30 can be uniquely determined.

[0109] Next, in S460, as shown in FIG. 12, the smartphone 20 displays an icon of the key FOB 30 at a position on the GUI corresponding to the identified position of the key FOB 30. At this time, as shown in FIG. 13, the smartphone 20 may calculate the likelihood of the identified position of the key FOB 30 and change the display method of the key FOB 30 position depending on the likelihood. For example, the smartphone 20 may dim the icon of the key FOB 30 when the likelihood is relatively low, and may make the icon of the key FOB 30 darker and clearer as the likelihood increases. When the smartphone 20 is moved and distance measurements are repeatedly performed, the smartphone 20 may increase the likelihood of a position that is more frequently estimated as the position of the key FOB 30.

[0110] Next, in S470, the smartphone 20 determines whether the user has terminated the key finder app. If it is determined that the key finder app has been terminated, the smartphone 20 terminates this process. If it is determined that the key finder app has not been terminated, the smartphone 20 returns to the process of S390 and repeats the distance measurement.

[0111] <2-2A-2. First communication process executed by the digital key ECU and key FOB> The first communication process executed by the digital key ECU 10 and the key FOB 30 will be described with reference to the flowchart of FIG.

[0112] In S480, the digital key ECU 10 and the key FOB 30 receive the digital key A from the smartphone 20 via BLE communication and store the digital key A in the secure memory 12, 33. The digital key ECU 10 and the key FOB 30 only store the digital key A in the secure memory 12, 33 when they receive the digital key A for the first time.

[0113] Next, in S490, the digital key ECU 10 and the key FOB 30 determine whether they have received a ranging signal via BLE communication from the smartphone 20. That is, they determine whether they have received a CW signal and an RTT signal from the smartphone 20. If they determine that they have received a ranging signal, the digital key ECU 10 and the key FOB 30 proceed to the process of S500. If they determine that they have not received a ranging signal, they repeat the process of S490.

[0114] In the S500, the digital key ECU 10 and the key FOB 30 return a ranging signal to the smartphone 20 via BLE communication. Next, in S510, the digital key ECU 10 and the key FOB 30 determine whether BLE communication with the smartphone 20 has been interrupted. That is, they determine whether a polling signal is being received from the smartphone 20 at the set polling period. If it is determined that BLE communication with the smartphone 20 has been interrupted, the process proceeds to S520. If it is determined that BLE communication with the smartphone 20 has not been interrupted, the process returns to S490.

[0115] In S520, the digital key ECU 10 and the key FOB 30 terminate the wireless connection with the smartphone 20 via BLE communication, and this process ends.

[0116] <2-2A-3. First communication process executed by home appliance> The first communication process executed by the air conditioner 40 and the television 50 will be described with reference to the flowchart of FIG.

[0117] In S530, the air conditioner 40 and the television 50 receive the digital key B shared with them from the smartphone 20 via BLE communication and store the digital key B in the memory 43. The air conditioner 40 and the television 50 need only store the digital key B in the memory 43 when they receive the digital key B for the first time.

[0118] Subsequently, in steps S540 to S570, the air conditioner 40 and the television 50 execute the same processes as those in steps S490 to S520.

[0119] <2-2A. Second Example> In the second embodiment, the smartphone 20 is used as the master, and the communication device and key FOB 30 are used as slaves, and the distance from the smartphone 20 to each of the communication device and key FOB 30 is measured. The communication device is a device that has a fixed location and has BLE communication functionality. In this embodiment, the communication device is one or more of the vehicle 200 and the first home appliance (specifically, an air conditioner) 40. After measuring the distance to each of the communication device and key FOB 30, the smartphone 20 transfers master authority to the communication device for a predetermined period of time. The communication device is used as the master, and the key FOB 30 is used as the slave, and the communication device measures the distance to the key FOB 30. The position of the key FOB 30 is identified by measuring the distance with the smartphone 20 and communication device used as the master.

[0120] <2-2B-1. Second key search process executed by smartphone> The second key search process executed by the smartphone 20 will be described with reference to the flowcharts of FIGS. 18A and 18B.

[0121] In steps S580 to S630, the smartphone 20 executes the same processes as those in steps S300 to S350. In S640, the smartphone 20 prompts the user to place icons of the smartphone 20 and one or more communication devices (i.e., the digital key ECU 10 or the air conditioner 40) wirelessly connected via BLE communication on the GUI on the screen. For example, the smartphone 20 prompts the user to place the icons of the smartphone 20 and the air conditioner 40 on the image of the room on the screen so that they correspond to their actual installation positions in the room. This determines, for example, the position (x1, y1) of the air conditioner 40 and the position (x2, y2) of the smartphone 20 on the app, as shown in FIG. 17.

[0122] Next, in S650 to S670, the smartphone 20 executes the same processes as in S370 to S390, and measures the distance d11a to the communication device. Next, in S680, the smartphone 20 measures the distance d22a to the key FOB 30 via BLE CS communication.

[0123] Next, in S690, the smartphone 20 transmits a master authority delegation request and the delegation permission time Ta to the communication device arranged on the GUI. As a result, the air conditioner 40 functions as the master for the delegation permission time Ta.

[0124] Next, in S700, the smartphone 20 terminates the wireless connection via BLE communication with the communication device placed on the GUI. Next, in S710, the smartphone 20 determines whether the delegation permission time Ta has elapsed since transmitting the authority delegation request to the communication device (i.e., the air conditioner 40 or the vehicle 200). If it is determined that the delegation permission time Ta has elapsed, the process proceeds to S720, and if it is determined that the delegation permission time Ta has not elapsed, the process returns to S700.

[0125] In S720, the smartphone 20 resumes wireless connection via BEL communication with the communication device placed on the GUI. In S730, the smartphone 20 receives the distance d33b to the key FOB 30 measured by the communication device from the communication device placed on the GUI via BLE communication.

[0126] Next, in S740, the smartphone 20 determines the position of the key FOB 30 based on the position of the smartphone 20, the position of the communication device placed on the GUI, the distance d22a from the smartphone 20 to the key FOB, the distance d33b from the key FOB 20 to the communication device, and the distance d11a from the communication device to the smartphone 20. Next, in S750, the smartphone 20 executes the same processing as in S470.

[0127] <2-2B-2. Second communication process executed by key FOB> The second communication process executed by the key FOB will be described with reference to the flowchart of FIG.

[0128] In S760, the key FOB 30 receives the digital keys A and B shared with it from the smartphone 20 via BLE communication and stores the digital keys A and B in the secure memory 33. The key FOB 30 only stores the digital keys A and B in the secure memory 33 when it receives the digital keys A and B for the first time.

[0129] Next, in steps S770 to S800, the key fob 30 executes the same processes as in steps S490 to S520. Next, in S810, the key FOB 30 determines whether or not it has received a ranging signal via BLE communication from the air conditioner 40 or the digital key ECU 10. If it determines that it has received a ranging signal from the air conditioner 40 or the digital key ECU 10, it proceeds to S820, and if it determines that it has not received a ranging signal, it proceeds to S830.

[0130] In S820, the key FOB 30 returns a distance measurement signal to the air conditioner 40 or the digital key ECU 10 via BLE communication. Next, in S830, the key FOB 30 determines whether BLE communication with the air conditioner 40 or the digital key ECU 10 has been interrupted. If the key FOB 30 determines that BLE communication with the air conditioner 40 or the digital key ECU 10 has been interrupted, the process proceeds to S840. If the key FOB 30 determines that BLE communication has not been interrupted, the process returns to S810.

[0131] In S840, the key fob 30 terminates the wireless connection via BLE communication with the air conditioner 40 or the digital key ECU 10, and ends this process.

[0132] <2-2B-3. Second communication process executed by the Digi-Key ECU> The second communication process executed by the digital key ECU 10 will be described with reference to the flowchart of FIG.

[0133] In the S850, the digital key ECU 10 receives the digital key A from the smartphone 20 via BLE communication and stores the digital key A in the secure memory 12. The digital key ECU 10 only stores the digital key A in the secure memory 12 when it receives the digital key A for the first time.

[0134] Next, in S860 and S870, the digital key ECU 10 executes the same processes as in S490 and S500. Next, in S880, the digital key ECU 10 determines whether or not it has received the master authority delegation request and the delegation permission time Ta from the smartphone 20. If it determines that it has received the master authority delegation request and the delegation permission time Ta, it proceeds to processing of S890, and if it determines that it has not received them, it proceeds to processing of S930.

[0135] In S890, the Digi-Key ECU 10 changes its role from slave to master and measures the distance d33b to the key FOB 30 via BLE CS communication. Next, in S900, the digital-key ECU 10 determines whether the delegation permission time Ta has elapsed since receiving the master's authority delegation request. If the digital-key ECU 10 determines that the delegation permission time Ta has elapsed, it proceeds to S910. If the digital-key ECU 10 determines that the delegation permission time Ta has not elapsed, it returns to S890.

[0136] In S910, the digital key ECU 10 changes its role from master to slave and resumes wireless connection with the smartphone 20 via BLE communication. Next, in S920, the digital key ECU 10 transmits the distance d33b to the key FOB 30 to the smartphone 20 via BLE communication.

[0137] Next, in S930 and S940, the digital key ECU 10 executes the same processes as in S510 and S520.

[0138] <2-2B-4. Second communication process executed by the air conditioner> The second communication process executed by the air conditioner 40 will be described with reference to the flowchart of FIG.

[0139] In S950, the air conditioner 40 receives the digital key B from the smartphone 20 via BLE communication and stores the digital key B in the memory 43. The air conditioner 40 only needs to store the digital key B in the memory 43 when it receives the digital key B for the first time.

[0140] Next, in steps S960 to S1040, the air conditioner 40 executes the same processes as in steps S860 to S940.

[0141] <2-3. Effects> According to the second embodiment described above in detail, the following effects are achieved. (2-1) By executing the key search program, the smartphone 20 can realize the function as a key finder.

[0142] (2-2) The smartphone 20 can determine the location of the key FOB 30 based on the known positions of the air conditioner 40 and the television 50, the measured distance d3a from the key FOB 30, and the measured distances d1a and d2a from each of the air conditioner 40 and the television 50.

[0143] (2-3) By repeatedly performing BLE CS communication while the user moves the smartphone 20, the smartphone 20 can identify the location of the key FOB 30. (2-4) The smartphone 20 can strengthen the security of the vehicle 200 by changing the digital key B used for BLE communication with the air conditioner 40 and the television 50 to the digital key A used for BLE communication with the key FOB 30.

[0144] (2-5) The smartphone 20 calculates the likelihood of the location of the identified key FOB 30, allowing the user to recognize the reliability of the location of the identified FOB key. (2-6) The smartphone 20 displays the location of the identified key FOB 30 according to the calculated likelihood, allowing the user to intuitively recognize the reliability of the location of the identified key FOB 30.

[0145] (3. Third Embodiment) <3-1. Digi-Key ECU Learning Function> The third embodiment has the same basic configuration as the first embodiment, so differences will be described below. Note that the same reference numerals as those in the first embodiment indicate the same configuration, and reference will be made to the preceding description.

[0146] In the third embodiment, the digital key ECU 10 utilizes the BLE communication functions of multiple portable terminals, including the key FOB 30, to learn the movement trajectories of the multiple portable terminals and set optimal polling periods and outputs for each of the multiple portable terminals.

[0147] As shown in FIG. 22, in this embodiment, the multiple mobile terminals include a key FOB 30 and a smartphone 20. The smartphones 20 include a first smartphone 20A, a second smartphone 20B, and a third smartphone 20C. The first smartphone 20A, the second smartphone 20B, and the third smartphone 20C are carried by specific users and function as digital keys for the vehicle 200. Specifically, the first smartphone 20A is carried by person A, the second smartphone 20B is carried by person B, and the third smartphone 20C is carried by person C. The key FOB 30 is shared by person A, person B, and person C.

[0148] The movement trajectories of the first, second, and third smartphones 20A, 20B, and 20C vary depending on the location and time, and have a certain pattern according to the location and time. For example, as shown in FIG. 24, from Monday to Friday mornings, person A carries the first smartphone 20A and moves from his home through the front door and gate to his vehicle 200 parked in the parking lot next to his home. Also, as shown in FIG. 26, from Monday to Friday nights, person A carries the first smartphone 20A and moves from his office along the sidewalk to his vehicle 200 parked in the parking lot. Also, as shown in FIG. 28, on Saturday afternoons, person A carries the first smartphone 20A and moves from inside a supermarket to his vehicle 200 parked in the supermarket parking lot.

[0149] The Digi-key ECU 10 learns the movement trajectory for each of the identification information of the smartphone 20, the position of the vehicle 200 when the movement trajectory was acquired, and the time at which the position of the vehicle 200 was acquired. The Digi-key ECU 10 stores the movement trajectory learning results in the DB 11, linking the identification information of the smartphone 20 with the model of the smartphone 20, the position of the vehicle 200, and the time at which the position of the vehicle 200 was acquired. For example, as shown in FIG. 23 , the Digi-key ECU 10 stores the movement trajectory learning results in the DB 11, linking the identification information of the smartphone 20 with locations including home, work, and shopping, and times including morning, noon, and night.

[0150] Furthermore, the Digi-Key ECU 10 calculates the optimal values ​​for the polling period and output of the smartphone 20 based on the learning results of the movement trajectory. The Digi-Key ECU 10 sets the polling period according to the position of the smartphone 20. The Digi-Key ECU 10 also sets the output magnitude of the polling signal according to the model and polling period of the smartphone 20. For example, the Digi-Key ECU 10 increases the output if the smartphone 20 is a model with low reception sensitivity, and increases the output as the polling period becomes longer.

[0151] For example, the digital key ECU 10 acquires the movement trajectory of the smartphone 20, compares the acquired movement trajectory with the learning results stored in the DB 11, and determines that the acquired movement trajectory is the morning movement trajectory pattern of the first smartphone 20A, as shown in Figure 24. Then, as shown in Figure 25, the digital key ECU 10 sets the polling period to 3000 ms while the first smartphone 20A moves from the front door to the gate. Although the front door is close to the parking position of the vehicle 200, the learning results indicate that the first smartphone 20A will temporarily move away from the parking position of the vehicle 200. Therefore, the digital key ECU 10 sets a relatively long polling period while the first smartphone 20A moves from the front door to the gate.

[0152] When the first smartphone 20A reaches the gate, the Digi-Key ECU 10 shortens the polling period to 1000 ms until it is 8 m from the vehicle 200 and turns on the welcome lights of the vehicle 200. When the first smartphone 20A reaches the 8 m point, the Digi-Key ECU 10 shortens the polling period to 500 ms until it is 5 m from the vehicle 200 and verifies the digital key information of the first smartphone 20A to unlock the door. When the first smartphone 20A reaches the 5 m point, the Digi-Key ECU 10 shortens the polling period to 250 ms until it arrives at the vehicle 200.

[0153] Furthermore, if the digital key ECU 10 determines that the acquired movement trajectory of the first smartphone 20A is the movement trajectory pattern shown in Figure 26, the closer the first smartphone 20A is to the vehicle 200, the shorter the polling period is set, as shown in Figure 27. For example, when the first smartphone 20A reaches a distance of 8 m from the vehicle 200, the digital key ECU 10 shortens the polling period from 3000 ms to 1000 ms.

[0154] Furthermore, if the digital key ECU 10 determines that the acquired movement trajectory of the first smartphone 20A matches the movement trajectory pattern shown in FIG. 28 , as shown in FIG. 29 , the closer the first smartphone 20A is to the vehicle 200, the shorter the polling period is set. However, because there are many shoppers near the entrance of the supermarket and radio waves are difficult to reach, the polling period is shortened from 3000 ms to 1000 ms when the first smartphone 20A reaches a distance of 30 m from the vehicle 200. Furthermore, when the first smartphone 20A reaches a distance of 8 m from the vehicle 200, the polling period is shortened to 300 ms, which is shorter than usual. Furthermore, when the first smartphone 20A reaches a distance of 5 m from the vehicle 200, the polling period is shortened to 150 ms, which is shorter than usual. In particular, during times when the supermarket is holding a limited-time sale, the polling period is shortened earlier than usual because there are many shoppers and radio waves are difficult to reach.

[0155] Furthermore, the digital key ECU 10 compares the key FOB 30's movement trajectory with the learning results of the database 11 to determine which smartphone's learning result the key FOB 30's movement trajectory is closest to at the current time and location. That is, the digital key ECU 10 determines which user among person A, person B, and person C is using the key FOB 30. The digital key ECU 10 then sets the polling cycle and output for the current key FOB 30 to the polling cycle and output set for the learning result determined to be closest to the key FOB 30's movement trajectory.

[0156] <3-2. Processing> <3-2-1. Optimization process performed by the Digi-Key ECU> The optimization process executed by the digital key ECU 10 will be described with reference to the flowcharts of FIGS. 30A and 30B.

[0157] In the S1100, the digital key ECU 10 establishes a wireless connection with the smartphone 20 via BLE communication. Next, in S1110, the Digi-Key ECU 10 measures the distance to the smartphone 20 using multiple BLE antennas 70 through BLE CS communication with the smartphone 20.

[0158] Next, in S1120, the Digi-Key ECU 10 determines the location of the smartphone 20 by triangulation using multiple BLE antennas 70. Next, in S1130, the digital key ECU 10 acquires the position of the vehicle 200 based on the signal received by the GPS receiver 81, and acquires the time from the clock 82.

[0159] Next, in S1140, the digital key ECU 10 links the location of the vehicle 200, the time, the location of the smartphone 20, and the model of the smartphone 20, and stores them in the DB 11. Next, in S1150, the digital key ECU 10 determines whether the smartphone 20 is within the range of the wireless connection via BLE communication of the digital key ECU 10. If it is determined that the smartphone 20 is within the range of the wireless connection, the process returns to S1110. If it is determined that the smartphone 20 is not within the range of the wireless connection, the process proceeds to S1150.

[0160] In S1160, the digital key ECU 10 corrects an error value included in the movement trajectory of the smartphone 20 in response to the wireless connection with the smartphone 20 being interrupted. Specifically, the digital key ECU 10 corrects movement data in the movement trajectory of the smartphone 20 where the movement distance per unit time is longer than a movement threshold. For example, the digital key ECU 10 changes the error value to the average value of the movement data before and after the interruption.

[0161] In S1170, the digital key ECU 10 determines whether the DB 11 stores data on past movement trajectories corresponding to the current position of the vehicle 200, the time, the position of the smartphone 20, and the model of the smartphone 20. If it is determined that data on past movement trajectories is stored, the process proceeds to S1180. If it is determined that data on past movement trajectories is not stored, the process ends.

[0162] In S1180, the digital key ECU 10 learns the characteristics (i.e., patterns) of the movement trajectory of each model of smartphone 20 for each location and time based on the position of the vehicle 200, the time, the movement trajectory of the smartphone 20, and the model of the smartphone 20.

[0163] Next, in S1190, the Digi-Key ECU 10 predicts the user's behavior according to the model, location, and time of the smartphone 20 based on the learning results of S1180. That is, the Digi-Key ECU 10 predicts the future movement trajectory of the smartphone 20. Then, the Digi-Key ECU 10 optimizes the polling period and output of the BLE communication for the predicted movement trajectory of the smartphone 20.

[0164] The next time the Digi-Key ECU 10 establishes a wireless connection with the smartphone 20, it will perform BLE communication with the smartphone 20 based on the optimized polling cycle and output. This improves the responsiveness and power saving of the smartphone 20. The smartphone 20 has a battery life that is long enough, so even if BLE communication is performed using the default polling cycle and output settings, a certain degree of responsiveness and battery life are guaranteed. Therefore, the Digi-Key ECU 10 does not reflect the learning results in the polling cycle and output while the wireless connection with the smartphone 20 is established, but reflects the learning results after the wireless connection is disconnected, and uses the polling cycle and output that reflect the learning results when the next wireless connection is established.

[0165] Next, in S1200, the digital key ECU 10 determines whether a wireless connection via BLE communication has been established with the key FOB 30. If a wireless connection with the key FOB 30 has been established, the process proceeds to S1210. If a wireless connection with the key FOB 30 has not been established, the process ends.

[0166] In S1210, the digital key ECU 10 measures the distance to the key FOB 30 using multiple BLE antennas 70 through BLE CS communication with the key FOB 30. Next, in S1220, the Digi-Key ECU 10 determines the location of the key FOB 30 by triangulation using multiple BLE antennas 70.

[0167] Next, in S1230, the digital key ECU 10 acquires the position of the vehicle 200 based on the signal received by the GPS receiver 81, and acquires the time from the clock 82. Next, in S1240, the digital key ECU 10 associates the location of the vehicle 200, the time, and the location of the key FOB 30, and stores them in the DB 11.

[0168] Next, in S1250, the digital key ECU 10 determines whether the key FOB 30 is within the range of the wireless connection via BLE communication of the digital key ECU 10. If it is determined that the key FOB 30 is within the range of the wireless connection, the process proceeds to S1260. If it is determined that the key FOB 30 is not within the range of the wireless connection, the process proceeds to S1290.

[0169] In S1260, the digital key ECU 10 corrects an error value included in the movement trajectory of the key FOB 30 while wirelessly connected to the key FOB 30. The error value correction is similar to the process of S1160.

[0170] Next, in S1270, the digital key ECU 10 detects the smartphone 20 corresponding to the movement trajectory that has a tendency matching the movement trajectory of the key FOB 30 among the movement trajectories of each smartphone 20 stored in the DB 11 and that are linked to the current location and time.

[0171] Next, in S1280, the digital key ECU 10 optimizes the polling cycle and output of the BLE communication with the key FOB 30 based on the learning results of the smartphone 20 detected in S1270. The digital key ECU 10 then returns to the process of S1210 and performs BLE communication with the key FOB 30 based on the optimized polling cycle and output. This improves the responsiveness and power saving of the key FOB 30. The key FOB 30 has a limited battery life. Therefore, the digital key ECU 10 optimizes the polling cycle and output while establishing a wireless connection with the key FOB 30.

[0172] In addition, in S1290, the digital key ECU 10 determines whether or not there is data on the movement trajectory of the key FOB 30 in response to the wireless connection with the key FOB 30 being cut off. If it is determined that there is data on the movement trajectory of the key FOB 30, the process proceeds to S1300. If it is determined that there is no data on the movement trajectory of the key FOB 30, the process ends.

[0173] In S1300, the digital key ECU 10 adds the data of the movement trajectory of the key FOB 30 to the learning data of the smartphone 20 detected in S1270, updates the learning data, and ends this process.

[0174] <3-2-2. Communication processing performed by smartphones> The communication process executed by the smartphone 20 will be described with reference to the flowchart of FIG. In S1310, the smartphone 20 establishes a wireless connection with the digital key ECU 10 via BLE communication.

[0175] Next, in S1320, the smartphone 20 measures the distance to the vehicle 200 using multiple BLE antennas 70 through BLE CS communication with the digital key ECU 10. Next, in S1330, the smartphone 20 determines whether the smartphone 20 is within the range of wireless connection via BLE communication with the digital key ECU 10. If it is determined that the smartphone 20 is within the range of wireless connection, the process returns to S1320. If it is determined that the smartphone 20 is not within the range of wireless connection, the process ends.

[0176] <3-2-3. Communication process performed by key FOB> The communication process executed by the key FOB 30 will be described with reference to the flowchart of FIG.

[0177] In S1340, the key FOB 30 establishes a wireless connection with the digital key ECU 10 via BLE communication. In S1350, the key FOB 30 measures the distance to the vehicle 200 using multiple BLE antennas 70 through BLE CS communication with the digital key ECU 10.

[0178] Next, in S1360, the key FOB 30 determines whether or not it has received the optimal values ​​for the polling period and output of BLE communication from the digital key ECU 10. If it is determined that the optimal values ​​for the polling period and output have been received, it proceeds to S1370, and if it is determined that the optimal values ​​for the polling period and output have not been received, it proceeds to S1380.

[0179] In S1370, the key FOB 30 sets the polling period and output to the optimum values ​​received from the digital key ECU 10. In S1380, the key FOB 30 determines whether it is within the range of the wireless connection via BLE communication with the digital key ECU 10. If it is determined that the key FOB 30 is within the range of the wireless connection, the process returns to S1340. If it is determined that the key FOB 30 is not within the range of the wireless connection, the process ends.

[0180] <3-3.Effects> According to the third embodiment described above, the following effects are achieved. (3-1) When a user approaches vehicle 200 carrying smartphone 20 to use smartphone 20 as a digital key for vehicle 200, the movement trajectory to vehicle 200 varies depending on the vehicle's location, such as a parking lot at home or a supermarket parking lot. Digi-key ECU 10 determines the polling cycle of smartphone 20 based on learned data of the movement trajectory learned for each model of smartphone 20 and the location of vehicle 200. This allows Digi-key ECU 10 to communicate with smartphone 20 via BLE at an optimized polling cycle depending on the relative position of smartphone 20 with respect to vehicle 200.

[0181] (3-2) The digital key ECU 10 can identify the position of the smartphone 20 relative to the vehicle 200 based on the distance measurement results from each of the multiple BLE antennas 70. (3-3) Even in the same location, such as a supermarket parking lot, the number of people near the route from smartphone 20 to vehicle 200 varies depending on the time of day, and there are times when radio waves from vehicle 200 can easily reach smartphone 20 and times when they cannot. Therefore, by learning the model of smartphone 20, the location of vehicle 200, and the movement trajectory for each time, Digi-key ECU 10 can determine the optimal polling period.

[0182] (3-4) The digital key ECU 10 can determine the optimal polling period for the key FOB 30 based on the vehicle position, the movement trajectory of the key FOB 30, and the learning data.

[0183] (3-5) By comparing the movement trajectory of the key FOB 30 with the learning data, the digital key ECU 10 can estimate which of the users of the first, second, and third smartphones 20A, 20B, and 20C is carrying the key FOB 30. Furthermore, the digital key ECU 10 can determine the polling period of the key FOB 30 based on the learning data corresponding to the smartphone 20 of the estimated user.

[0184] (3-6) The digital key ECU 10 can use the data of the movement trajectory of the key FOB 30 to learn the movement trajectory of the smartphone 20 corresponding to the estimated user by linking it to the smartphone 20 of the estimated user and saving it.

[0185] (3-7) By transmitting the optimized polling cycle to the key FOB 30, the digital key ECU 10 can perform BLE communication with the key FOB 30 with excellent responsiveness and power saving.

[0186] (4. Other Embodiments) Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments and can be implemented in various modified forms.

[0187] (a) In the first embodiment, the key FOB 30 corresponds to the second portable terminal of the present disclosure. However, the second portable terminal may be a portable terminal that functions as a key for the vehicle 200 other than the key FOB 30. For example, the second portable terminal may be a smartphone other than the smartphone 20, a tablet terminal, a wearable device, or the like.

[0188] (b) Multiple functions of one component in the above embodiments may be realized by multiple components, or one function of one component may be realized by multiple components. Also, multiple functions of multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Also, part of the configuration of the above embodiments may be omitted. Also, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments. [Explanation of symbols]

[0189] 10...Digi-key ECU, 11...DB, 12,33...Secure memory, 20...Smartphone, 30...Key FOB, 40...First home appliance, 50...Second home appliance, 60...Third home appliance, 70...BLE antenna, 100...Communication system, 200...Vehicle.

Claims

1. a first mobile terminal (20) that functions as an electronic key for a vehicle (200); a second mobile terminal (30) that functions as an electronic key for the vehicle and is configured to be able to communicate with the first mobile terminal via Bluetooth Low Energy (BLE); a vehicle control device (10) mounted on the vehicle and configured to be able to communicate with the first mobile terminal and the second mobile terminal via BLE; The first mobile terminal When a wireless connection is established between the vehicle control device and the vehicle control device via the BLE communication, a polling signal is transmitted to the vehicle control device at a first cycle; When a wireless connection is established between the second mobile terminal and the second mobile terminal through the BLE communication, a polling signal is transmitted to the second mobile terminal at a second period longer than the first period; When a wireless connection by the BLE communication is established with each of the vehicle control device and the second mobile terminal, timing information regarding a timing at which the second mobile terminal transmits an advertising signal is received from the second mobile terminal, and the timing information is transmitted to the vehicle control device; the vehicle control device is configured to transition to a scan state in which the advertising signal can be received, based on the timing information received from the first mobile terminal. Communication system.

2. The vehicle control device (10) is configured to maintain an unestablished wireless connection between the vehicle control device and the second mobile terminal (30) through the BLE communication when a first distance from the first mobile terminal (20) to the vehicle (200) is less than a distance threshold. The communication system of claim 1 .

3. The first mobile terminal (20) and / or the vehicle control device (10) are configured to measure the first distance based on signal characteristics of the BLE communication. The communication system according to claim 2 .

4. The first mobile terminal (20) and / or the vehicle control device (10) are configured to transmit a ranging signal and calculate the first distance based on a phase and / or a time of flight of the ranging signal. The communication system according to claim 3 .

5. The first mobile terminal (20) and / or the second mobile terminal (30) are configured to measure a second distance from the first mobile terminal to the second mobile terminal based on signal characteristics of the BLE communication.

3. A communication system according to claim 1 or 2.

6. The first mobile terminal (20) and / or the second mobile terminal (30) are configured to transmit ranging signals and calculate the second distance based on a phase and / or a time of flight of the ranging signals. The communication system according to claim 5 .

7. A vehicle control device (10) is mounted on a vehicle (200) and configured to be capable of Bluetooth Low Energy (BLE) communication with a first mobile terminal (20) and a second mobile terminal (30) that function as electronic keys of the vehicle, Transmitting an advertising signal to the first mobile terminal to establish a wireless connection with the first mobile terminal through the BLE communication; receiving, via the first mobile terminal, timing information regarding a timing at which the second mobile terminal transmits an advertising signal; and transitioning to a scan state in which an advertising signal transmitted from the second mobile terminal can be received based on the received timing information. Vehicle control device.

Images