UWB communication between vehicle system and portable identifier

Abstract

A method for communicating between a portable identifier and a vehicle system in which the portable identifier is stored is presented. The system and identifier are configured to communicate using a UWB communication protocol within a first perimeter around the vehicle, and to communicate using a BLE communication protocol within a second perimeter around the vehicle. The method comprises, when a user carrying the identifier approaches the vehicle, detecting S10 that the identifier is located within the second perimeter, performing S20 a test for initiating UWB communications, where success of one completed test results in initiation of the communications S30, detecting S40 that the identifier is located at a distance less than or equal to a predetermined close distance, and modifying S50 the communications to reduce the frequency of the UWB exchange. The method provides improved communication between the identifier and the system.

Description

Technical Field

[0001] The present invention relates to a method for communication between a portable identifier and a vehicle system, a computer program for such a system and / or such a portable identifier, and a storage medium for such a program, such a portable identifier, and such a vehicle system. Background Technology

[0002] Vehicles currently exist equipped with systems that store one or more portable identifiers. These portable identifiers can be portable devices, such as remote keys or smartphones. Each identifier includes an electrical power source (e.g., a battery) that allows it to be portable. Such a system allows the vehicle to perform functions based on the location of one or more portable identifiers, such as, for example, unlocking doors and / or starting the vehicle.

[0003] To perform these functions, each portable identifier can be configured to communicate with the system using one or more communication protocols. For example, the portable identifier and the system can be configured to communicate using the UWB (Ultra-Wideband) communication protocol and the BLE (Bluetooth Low Energy) communication protocol. However, using these one or more communication protocols reduces the battery life of the portable identifier.

[0004] It is worth noting that UWB communication typically involves periodic UWB exchanges. The involvement of portable identifiers in these periodic UWB exchanges significantly depletes their battery life.

[0005] Therefore, there is a need to improve the communication between this portable identifier and this system. Summary of the Invention

[0006] To this end, a method for communication between a portable identifier and a vehicle system that has stored the portable identifier is proposed. The identifier includes an electrical power source. The system and the identifier are configured to communicate using a UWB communication protocol within a first perimeter around the vehicle and using a BLE communication protocol within a second perimeter around the vehicle. The first perimeter is included within the second perimeter. When a user carrying the identifier approaches the vehicle, the method includes the following five steps. The first step is a first detection step. The first detection step involves detecting that the identifier is located within the second perimeter. The second step is performed after the first detection step. The second step involves performing a test for initiating communication using the UWB communication protocol. The completed test is performed periodically in a first cycle. The third step involves the success of one of the completed tests, resulting in the initiation of communication. The initiated communication includes periodic UWB exchange in a second cycle. The second cycle is shorter than the first cycle. The fourth step is a second detection step. The second detection step involves detecting that the identifier is located at a distance less than or equal to a predetermined proximity distance. The fifth step is performed after the second detection step. The fifth step involves modifying the communication such that the UWB exchange is performed periodically in a third cycle. The third cycle is shorter than the second cycle.

[0007] The method may further include a third detection step. The third detection step may involve detecting that the identifier is located inside the vehicle. The method may also include, after the third detection step, modifying the communication such that UWB switching is performed periodically in a fourth cycle. The fourth cycle may be longer than the third cycle and / or shorter than the second cycle.

[0008] The method may further include: after starting the vehicle's engine, pausing or modifying communication so that UWB switching occurs periodically in a fifth cycle. The fifth cycle may be longer than the fourth cycle. Optionally, the fifth cycle may also be longer than the second cycle.

[0009] Optionally, the method may include: re-establishing communication after a communication interruption when the vehicle is traveling at a speed less than or equal to a predetermined speed limit.

[0010] The method may further include: after stopping the vehicle's engine, when communication is paused, re-establishing communication using a UWB communication protocol. The re-established communication may include periodic UWB exchanges performed in a third cycle. The method may further include: after starting the vehicle's engine, when communication includes periodic UWB exchanges performed in a fourth or fifth cycle, modifying the communication such that the UWB exchanges are performed periodically in a third cycle. The method may further include a fourth detection step. The fourth detection step may involve detecting that the identifier is located at a distance greater than or equal to a predetermined proximity distance. The method may further include: after the fourth detection step, pausing the re-established communication.

[0011] The first cycle can be a multiple of the second cycle. The second cycle can be a multiple of the third cycle. The fourth cycle can be a multiple of the third cycle.

[0012] The identifier may include a microcontroller, a BLE component, and a UWB component. Communication initiation may involve the microcontroller sending a wake-up signal to the UWB component. Optionally, the BLE component may be integrated into the microcontroller.

[0013] The electrical energy source can be a battery, preferably a button cell, and / or have a diameter of less than 25 mm and / or a height of less than 8 mm, for example, less than 6 mm.

[0014] A first computer program for such a portable identifier is also proposed. The computer program includes instructions that, when executed by a processor of the portable identifier, cause the processor to perform one or more steps (e.g., all steps) of the method.

[0015] A first computer-readable storage medium for storing such a first computer program is also proposed.

[0016] A portable identifier is also proposed. The portable identifier includes a first storage medium. The portable identifier is configured to perform one or more steps (e.g., all steps) of this method.

[0017] A second computer program for such a vehicle system is also proposed. This computer program includes instructions that, when executed by a processor of the vehicle system, cause the processor to perform one or more steps (e.g., all steps) of this method.

[0018] A second computer-readable storage medium for storing such a second computer program is also proposed.

[0019] A vehicle system storing a portable identifier is also proposed. The vehicle system includes such a second storage medium. The vehicle system is configured to perform one or more steps (e.g., all steps) of this method.

[0020] A vehicle system storing a portable identifier is also proposed. The vehicle system includes such a second storage medium. The vehicle system is configured to perform one or more steps (e.g., all steps) of this method.

[0021] A third procedure, comprising the first and second procedures, was also proposed. Attached Figure Description

[0022] Non-limiting examples will be described with reference to the following figures:

[0023] Figure 1 A flowchart illustrating an example of this method is shown.

[0024] Figure 2 An example of communication between a portable identifier and a vehicle system according to this method is shown.

[0025] Figure 3 An example of periodic UWB switching in the first, second, third, fourth, and fifth cycles is shown.

[0026] Figure 4 An example of the architecture of a portable identifier is illustrated. Detailed Implementation

[0027] refer to Figure 1 The flowchart presents a method for communication between a portable identifier and a vehicle system storing the portable identifier. The identifier includes an electrical power source. The system and the identifier are configured to communicate using a UWB communication protocol within a first perimeter around the vehicle and using a BLE communication protocol within a second perimeter around the vehicle. The first perimeter is included within the second perimeter. When a user carrying the identifier approaches the vehicle, the method includes the following five steps. The first step is a first detection step S10. The first step S10 involves detecting that the identifier is located within the second perimeter. A second step is performed after the first detection step S10. The second step includes performing a test S20 for initiating communication using the UWB communication protocol. The completed test is performed periodically in a first cycle. The third step involves the success of one of the completed tests that leads to the initiation of communication S30. The initiated communication includes periodic UWB exchange in a second cycle. The second cycle is shorter than the first cycle. The fourth step is a second detection step S40. The second detection step S40 involves detecting that the identifier is located at a distance less than or equal to a predetermined proximity distance. The fifth step is performed after the second detection step S40. The fifth step involves modifying the S50 communication so that UWB switching occurs periodically in a third cycle. The third cycle is shorter than the second cycle.

[0028] This method provides improved communication between portable identifiers and vehicle systems.

[0029] In practice, this method allows the UWB exchange frequency between the portable reader and the vehicle system to adjust according to changes in the distance between them. Specifically, the method allows the frequency to increase as the user approaches the vehicle. This frequency increase allows for reduced power consumption of the portable reader when the user moves away from the vehicle. In effect, reducing the frequency results in less UWB exchange between the reader and the system, which reduces the reader's power consumption. Therefore, this method improves the battery life of the portable reader.

[0030] Furthermore, this method allows for higher frequency UWB switching when the user approaches the vehicle, providing high accuracy for vehicle functions (such as location identifiers) used when the user is near the vehicle. Therefore, this method is particularly effective in improving the power life of portable identifiers, i.e., without degrading functions that use UWB communication and are used near the vehicle.

[0031] The vehicle system and the portable identifier are configured to communicate using the UWB (Ultra-Wideband) communication protocol and the BLE (Bluetooth Low Energy) communication protocol. For each protocol, communication is understood as representing the exchange of signals between the portable identifier and the vehicle system according to the communication protocol, such as periodic exchanges.

[0032] Specifically, when the portable identifier is within a first perimeter around the vehicle, the system and the portable identifier use the UWB communication protocol; that is, an exchange using the UWB protocol (UWB exchange) can be performed within this first perimeter. This first perimeter can include all locations within a first predetermined distance (e.g., 7 meters) from the vehicle system. On a 2D plane representing the ground, this first perimeter can be represented by a circle centered on the vehicle with a radius equal to the first predetermined distance.

[0033] When the portable identifier is within a second perimeter surrounding the vehicle, the system and the portable identifier use the BLE communication protocol; that is, exchanges using the BLE protocol (BLE exchanges) can be performed within this second perimeter. This second perimeter can include all locations at a distance from the vehicle system less than or equal to a second predetermined distance (e.g., 40 meters). On a 2D plane representing the ground, like the first perimeter, this second perimeter can be represented by a circle centered on the vehicle, and it can itself have a radius equal to the second predetermined distance.

[0034] The steps of this method can be performed by a portable identifier or by a vehicle system. Alternatively, one or more steps can be performed by a portable identifier, and one or more other steps can be performed by a vehicle system. In some examples, some steps can also be performed by both devices (the portable identifier and the vehicle system).

[0035] In some examples, the vehicle system may have stored several portable identifiers. In this case, when a user carrying one of these portable identifiers approaches the vehicle, the steps of the method can be performed for that identifier. When another portable identifier approaches the vehicle (e.g., by being carried by the same user or another user), the method can be repeated for that other identifier.

[0036] When a user carrying the identifier approaches the vehicle, the method performs steps S10 to S50. For example, the method can perform steps S10 to S50 as the user follows a path to their vehicle, i.e., from their residence (e.g., their home, their office, a hotel, or a business such as a shop or restaurant) to the vehicle. The method can also perform these steps S10 to S50 after the portable identifier has been reactivated. For example, once the user has retrieved the portable identifier and the portable identifier has reactivated itself, the method can perform these steps S10 to S50. This reactivation can be performed automatically by the portable identifier after motion is detected. When the user arrives at the vehicle along the path, the portable identifier may initially be outside the second perimeter and then may enter the second perimeter at a given moment on the path. At this point, the method can perform step S10. Alternatively, the identifier may already be inside the second perimeter when it is activated (e.g., when it is placed on a piece of furniture near the vehicle). In this case, step S10 can be performed once activated.

[0037] After performing step S10, the method includes performing a test for initiating UWB communication (step S20). Specifically, the method performs step S20 before the identifier enters the first perimeter. Along the path adopted by the user, the portable identifier successively enters the second perimeter and then the first perimeter (the second perimeter is wider and includes the first perimeter). The method performs step S20 during the portion of the path within the second perimeter and before entering the first perimeter.

[0038] When the identifier enters the first perimeter, one of the tests succeeds, which leads to the initiation of UWB communication (step S30). Once the identifier reaches a distance less than or equal to the predetermined proximity distance, the method includes a second detection step S40, which involves detecting that the identifier is at such a distance, and then modifying the period of the UWB exchanges in S50 to increase their frequency.

[0039] In some examples, the method can be repeated for each trip to the vehicle. For example, the method can be repeated for each home-to-vehicle, work-to-vehicle, hotel-to-vehicle, and / or business-to-vehicle trip by a user carrying a portable reader.

[0040] When the identifier enters the second perimeter (i.e., the BLE communication perimeter), detection step S10 can be performed. Detection step S10 may involve the successful execution of one or more first BLE exchanges between the vehicle system and the portable identifier. This or these first BLE exchanges may each involve the system sending a BLE signal, which the identifier then receives. Alternatively, for each exchange, the BLE signal may be sent by the identifier and then received by the system. The success of these one or more first BLE exchanges between the identifier and the system may mean that the portable identifier is within the second perimeter, i.e., it is within the system's range. Unsuccessful exchange tests may have been performed prior to the success of these one or more first BLE exchanges (because the identifier was not yet within the second perimeter at that time).

[0041] Following the first detection step S10, the method includes performing a test S20 to initiate UWB communication. Completion of each test may include the identifier sending a signal using the UWB communication protocol and then listening for signals sent by the system in response (or conversely, the system sending a signal and listening for signals sent by the identifier in response). Each test may fail if no signal is received in response (e.g., after a predetermined listening time), or each test may succeed if a signal is received in response during the listening period.

[0042] The test is performed periodically in a first cycle. This means that a test can be performed every X milliseconds, where X is the duration of the first cycle. At the beginning of each cycle, the test may include a recognizer or a system that sends a signal. The listening cycle may correspond to the remaining time within X milliseconds after the time used to send the signal has elapsed. In some examples, the first cycle may be less than 800 milliseconds and / or greater than 350 milliseconds, for example, approximately 576 milliseconds. Each test may last for 8 milliseconds. The current in the portable recognizer may then be greater than 200 μA and / or less than 600 μA, for example, approximately 400 μA.

[0043] After one of the tests is successful, the method includes initiating S30 UWB communication. UWB communication can be initiated directly after the first successful test. Initiating S30 may include performing one or more UWB exchanges between the portable identifier and the system, specifically to allow negotiation of one or more communication parameters between the portable identifier and the system. The initiated communication then includes a UWB exchange with one or more negotiated communication parameters. The UWB exchanges of the initiated communication are periodic with a second cycle. This means that a UWB exchange can be performed every Y milliseconds, where Y is the duration of the second cycle. The duration of the second cycle is less than the duration of the first cycle. For example, the first cycle can be a multiple of the second cycle. The first cycle can be equal to twice the second cycle. In some examples, the second cycle can be less than 350 milliseconds and / or greater than 150 milliseconds, for example, approximately 288 milliseconds. Each UWB exchange can last for 20 milliseconds. The current in the portable identifier can then be greater than 1,000 uA and / or less than 2,000 uA, for example, approximately 1,200 uA.

[0044] After initiating S30 UWB communication, a second detection step S40 is performed. The second detection step S40 may include monitoring the distance between the portable identifier and the system. Monitoring may include measuring the distance between the portable identifier and the system at regular intervals, and for each measurement, comparing the measured distance with a predetermined proximity distance (a second detection occurs when the measured distance becomes less than or equal to the predetermined proximity distance). The predetermined proximity distance may be less than the radius of the first perimeter (e.g., a portion of which is 7 meters). For example, the predetermined proximity distance may be less than 5 meters and / or greater than 1 meter (e.g., approximately equal to 3 meters).

[0045] Distance measurements can be performed in any manner. For example, measurements can be performed based on UWB exchanges from initiating UWB communications. Each UWB exchange includes a distance measurement. In this case, the measurements can be performed periodically with the same second cycle. Each distance measurement can be performed based on a UWB exchange between the portable identifier and the system, and can include calculating the time-of-flight of the UWB signal to cover the round-trip distance between the identifier and the system. Such measurements based on UWB exchanges can include the distance and location of identifiers around the vehicle.

[0046] Following the second detection step S40, a modification S50 is performed to adjust the frequency of UWB switching. Modification S50 may include increasing the frequency of UWB switching, i.e., increasing the frequency of transmitting and receiving signals that constitute these UWB switches. For example, the UWB switching may be programmed, and modification S50 may include modifications to this programming to multiply the initially planned number of UWB switches by n, where n is a positive integer. For example, modification S50 may involve performing two or three times the number of UWB switches.

[0047] After modifying S50, communication includes periodic UWB switching in a third cycle, shorter than the second cycle (some of these UWB switching programs are cancelled). For example, the second cycle can be a multiple of the third cycle. The second cycle can be three times the third cycle. In some examples, the third cycle can be less than 150 milliseconds and / or greater than 50 milliseconds, for example, approximately 96 milliseconds. Each UWB switch can last for 20 milliseconds. The current in the portable identifier can then be greater than 3,000 μA and / or less than 4,000 μA, for example, approximately 3,600 μA.

[0048] Once the communication has been modified (S50), the method can include performing one or more functions based on UWB exchange of the modified communication. These functions may include remotely locking and / or starting the vehicle, for example, once the user is closer than a safe distance (less than a predetermined proximity). For example, the method may include locking and / or starting the vehicle when the user is within 4 meters of it. In this case, the predetermined proximity is greater than 4 meters. In some examples, the method may include performing a welcome function when the user is 3 meters from the vehicle as the user approaches. Alternatively or additionally, the method may include performing a function to automatically open the vehicle doors when the user is within an unlocking distance (e.g., equal to 1.2 meters). When the user leaves their vehicle, the method may include performing a vehicle locking function when the user is within a locking distance. This locking distance may be regulated by law and may, for example, be less than or equal to 2 meters.

[0049] The modified UWB communication can continue, for example, until the user enters the vehicle. Afterward, the method can include detecting the identifier in the vehicle (third detection step S60). This third detection step S60 can be performed in the same manner as the first and second detection steps, i.e., based on distance measurements and determining that the identifier has entered the vehicle based on these measurements. After the third detection step S60, the method can include modifying the communication such that UWB switching is performed periodically in a fourth cycle. This modification can be performed in the same manner as modification S50, i.e., by modifying the programming of the UWB switching, but reducing the frequency of UWB switching.

[0050] Following this second modification, communication includes periodic UWB exchanges in a fourth cycle longer than the third cycle (e.g., some of the programming for these UWB exchanges is cancelled). For example, the fourth cycle can be a multiple of the third cycle. The fourth cycle can be twice the third cycle. The fourth cycle can also be shorter than the second cycle (some of these UWB exchanges remain programmed, e.g., related to the programming used to initiate communication in step S30). This duration of the fourth cycle is optimal. In practice, it also allows for reduced power consumption while ensuring short response times, which is particularly useful for functions such as performing new authentication using UWB exchanges when a user presses a button to start the vehicle.

[0051] In some examples, the fourth cycle can be less than 150 milliseconds and / or greater than 50 milliseconds, for example, approximately 96 milliseconds. Each UWB exchange can last for 20 milliseconds. Then, the current in the portable identifier can be greater than 1,000 uA and / or less than 2,500 uA, for example, approximately 1,800 uA.

[0052] In some examples, the UWB system and the identifier can be configured to communicate using the UWB communication protocol for the shortest possible period, i.e., for example, the third period (e.g., 96 milliseconds). In this case, the method can perform UWB communication at different frequencies by canceling certain UWB exchanges relative to this UWB communication for the shortest possible period. For example, the method can perform the communication initiated in step S30 by canceling two out of three UWB exchanges, i.e., by skipping two UWB exchanges after each UWB exchange. The method can also perform the communication modified in step S50 by resuming all UWB exchanges. Similarly, the method can perform UWB communication for the fifth period by canceling forty-two UWB exchanges after each UWB exchange, or even by canceling one out of two UWB exchanges for the fourth period. The decision to skip UWB exchanges can be made by the vehicle system or by the portable identifier based on distance. When the system makes a decision, it can directly transmit the new period to the portable identifier using BLE communication. Alternatively, the system can be configured to transmit the distance of the identifier from the vehicle.

[0053] Now refer to Figures 2 to 4 Describe some examples.

[0054] [ Figure 2An example of communication between a portable identifier and a vehicle system according to this method is shown. The figure illustrates a vehicle system 100 that has stored a portable identifier 200 carried by a user. System 100 and identifier 200 are configured to communicate using a UWB communication protocol within a first perimeter 310 around vehicle 100 and a BLE communication protocol within a second perimeter 320 around vehicle 100. The figure illustrates the limitation 321 for BLE connectivity and the limitation 311 for UWB connectivity. The second perimeter 320 includes the first perimeter 310. Perimeters 310 and 320 are shown schematically only in the figure, and therefore the actual shape and scale of these perimeters are not shown in the illustration.

[0055] Figure 2 The activity of BLE component 400 and UWB component 410 when the method is executed is also shown. Figure 2 The activity of motion sensor 420 and microcontroller 430 is also shown.

[0056] When a user carrying the identifier approaches the vehicle along a trajectory passing through points 200, 201, and then 202, the method includes the following five steps. The first step is a first detection step S10. The first detection step S10 involves detecting that the identifier 200 is within the second perimeter 320. A second step is performed after the first detection step S10. The second step includes performing a test S20 for initiating communication using the UWB communication protocol. The completed test is performed periodically in a first cycle. The third step involves the success of one of the tests leading to the completion of the initiation of communication 412 S30. The initiated communication 412 includes periodic UWB exchange in a second cycle. The second cycle is shorter than the first cycle. The fourth step is a second detection step S40. The second detection step S40 involves detecting that the identifier 200 is at a distance less than or equal to a predetermined proximity distance (3 meters in this example). The fifth step is performed after the second detection step S40. The fifth step involves modifying the communication S50 such that the UWB exchange is performed periodically in a third cycle. The third cycle is shorter than the second cycle.

[0057] Figure 2 Steps S60 to S70 of the method are also shown, which are performed after the user enters the vehicle. At this point, the method includes a third detection step S60 detecting the presence of the identifier in the vehicle, followed by a modification of the communication such that UWB switching is performed periodically in a fourth cycle 414. As described above, the third detection step S60 and the modification of the communication are performed such that UWB switching is performed periodically in a fourth cycle 414.

[0058] In some examples, after starting the engine of vehicle 100, the method includes pausing communication S70. For example, the method may include detecting that the engine has been started (e.g., detecting that the user has pressed the ignition control button), and then immediately pausing communication S70. Pausing S70 may include canceling the programming of UWB exchange between the identifier and the system. Pausing S70 may also include placing the UWB component of the identifier into a standby state. In some examples, pausing S70 may also include storing the negotiated session parameters for the paused UWB communication. With this storage, UWB communication can be re-established without renegotiating these session parameters (i.e., by using the session parameters stored during pausing S70 and negotiated during initiation S30), particularly when the speed is reduced or when the engine of vehicle 100 stops, as described below. This improves the efficiency of the method. Pausing S70 further reduces power consumption.

[0059] In some examples, after pausing S70, the method may include re-establishing S71 communication when the vehicle is traveling at a speed less than or equal to a predetermined speed limit. For example, the method may include monitoring the vehicle's speed and verifying that the monitored speed has not become less than or equal to the predetermined speed limit (e.g., within a period longer than a predetermined cycle, such as several minutes). The predetermined speed limit may be less than or equal to 10 km / h and / or greater than or equal to 1 km / h, for example, approximately 3 km / h. The method may re-establish communication S70 with the same session parameters as before the pause.

[0060] The method can perform step S71 after the user has completed the trip they wish to take using the vehicle (e.g., from home to work, from home to a hotel, from home to a store, or vice versa), that is, once they have almost reached their destination, they then reduce the speed of the vehicle. For example, the method can perform step S71 before the user turns off the engine of the vehicle and leaves the vehicle.

[0061] In other examples ( Figure 2(Not shown in the diagram), after starting the engine of vehicle 100, instead of suspending communication, the method may include modifying the communication such that UWB exchanges are performed periodically in a fifth cycle. The fifth cycle may be, for example, longer than the fourth cycle, and optionally longer than the second cycle. For example, the fifth cycle may be greater than 1 second and / or less than 10 seconds, for example, approximately 4,032 milliseconds. This modification allows for reduced consumption of the portable identifier while maintaining the possibility of periodically checking the identifier's location. The method may perform this modification of the communication in the same manner as the modification of the communication, such that UWB exchanges are performed periodically in the fourth cycle (414), or in the same manner as modification S50, i.e., by modifying the programming of the UWB exchanges (e.g., by performing only one UWB exchange every Z milliseconds, where Z is equal to the duration of the fifth cycle). Each UWB exchange may last for 20 milliseconds. The current in the portable identifier may then be greater than 50 μA and / or less than 100 μA, for example, approximately 75 μA.

[0062] Figure 2 The method also describes steps S80 and S90, which are performed after the user has completed their desired journey using the vehicle (i.e., once they have arrived at their destination and left the vehicle). These steps S80 to S90 can be performed during the user's journey from the vehicle to their accommodation (e.g., their home, office, hotel, or business such as a shop or restaurant) and back to the vehicle. This accommodation can be the same as during the outbound journey, or it could even be a different accommodation.

[0063] During the departure process, the method may include a fourth detection step S80. The fourth detection step S80 involves detecting that the identifier is located at a distance greater than or equal to a predetermined proximity distance 210. The method may perform the fourth detection step in the same manner as the first, second, and third detection steps, i.e., by measuring the distance and comparing the measured distance with the predetermined proximity distance 210. After the fourth detection step S80, the method includes pausing the re-established communication in S90.

[0064] In some examples, the method may perform the pause S90 immediately after the fourth detection step S80. In other examples, the method may perform the pause S90 only at a later time. For example, the method may include modifying the UWB communication immediately after the fourth detection step and before the pause S90, for example, causing the UWB exchange to be performed periodically in a second cycle (416). In this case, the method may only perform the pause S90 when the user leaves the first perimeter 310. For example, the pause S90 may be caused by a failure of the UWB exchange between the system and the portable identifier (which is then no longer located within the first perimeter 310 around the vehicle).

[0065] In some examples, after pausing S90, the method may include performing tests (417) to initiate UWB communication. These tests may be performed in the same manner as in step S20. The method may stop performing the tests when the recognizer leaves the second perimeter 320, for example, after BLE communication is paused.

[0066] This method saves energy equivalent to more than four months of use for a portable identifier. In practice, the average time to travel from the boundary of the second perimeter to the boundary of the first perimeter is 20 seconds, the time to travel from the boundary of the first perimeter to within 3 meters of the vehicle is 4.7 seconds, the time to travel 3 meters to the vehicle is 2 seconds, and the time to start the vehicle and drive away is 10 seconds. Therefore, this method allows for a reduced frequency of UWB exchanges in the first 24.7 seconds (e.g., once every 192 milliseconds or less) and allows for maintaining a high frequency of UWB exchanges only in the last 2 seconds (e.g., once every 96 milliseconds).

[0067] Figure 3 Examples of periodic UWB switching performed in the first, second, third, fourth, and fifth cycles are shown. Specifically, Figure 3 An example of periodic UWB switching with a first cycle of 501 is shown. Each UWB switch can be approximately 20 milliseconds. The first cycle of 501 is 576 milliseconds. Figure 3 An example of periodic UWB switching with a second period of 502 is also shown. The second period of 502 is 288 milliseconds. The first period of 501 is twice the second period of 502. Figure 3 An example of periodic UWB switching with a third period of 503 is also shown. The third period of 503 is 96 milliseconds. The second period of 502 is three times the third period of 503. Figure 3 An example of periodic UWB switching with a fourth period of 504 is also shown, which is 192 milliseconds. The fourth period of 504 is twice the third period of 503. Figure 3 An example of a paused S70 communication 505 (excluding any UWB exchange) is also shown. Figure 3 An example of periodic UWB switching with a fifth period of 506 is also shown, which is 4,032 milliseconds. The fifth period of 506 is seven times the first period of 501.

[0068] Figure 4An example of a portable identifier architecture 800 is illustrated. Architecture 800 includes a UWB component 810, a BLE component 820, a microcontroller 840 integrating the BLE component 820, and internal communication 830 between the UWB component 810 and the BLE component 820 (via the microcontroller 840). Architecture 800 includes a UWB antenna 811 connected to the UWB component 810. Architecture 800 includes a BLE antenna 821 connected (via the microcontroller 840) to the BLE component 820. Internal communication 830 prevents the UWB component from integrating components for time measurement (e.g., resonators). Architecture 800 includes a motion sensor 860 connected to the microcontroller 840. Architecture 800 includes a battery 850 powering the UWB component 810 and the microcontroller 840. After prediction S40, the method includes initiating S30 UWB communication. Initiating S30 includes the microcontroller 840 sending a wake-up signal to the UWB component 810 using internal communication 830. Upon receiving a wake-up signal, the UWB component 810 can be powered by the device's electrical energy source 850. This method allows for reduced activity of the UWB component 810 when the user is away from the vehicle, thus reducing the risk of unnecessary consumption of electrical energy 850.

Claims

1. A method for communicating between a portable identifier (200) and a vehicle system (100) storing the portable identifier (200), the identifier (200) including an electrical power source, the system and the identifier (200) being configured to communicate using a UWB communication protocol within a first perimeter (310) around the vehicle and using a BLE communication protocol within a second perimeter (320) around the vehicle, the first perimeter (310) being included within the second perimeter (320), the method comprising: When a user carrying the identifier (200) approaches the vehicle (100): • First detection step (S10), the first detection step (S10) involves detecting that the recognizer (200) is located within the second perimeter (320); • After the first detection step (S10), a test for initiating communication using the UWB communication protocol is performed (S20), wherein the test is performed periodically in a first cycle; • Success of one of the completed tests results in the initiation of communication (412) (S30), the initiated communication (412) including periodic UWB exchange in a second cycle, wherein the second cycle is shorter than the first cycle; • Second detection step (S40), which involves detecting that the identifier (200) is located at a distance less than or equal to a predetermined proximity distance (210); and • After the second detection step (S40), the modification step (S50) involves modifying the communication so that UWB switching is performed periodically in a third cycle, wherein the third cycle is shorter than the second cycle.

2. The method according to claim 1, wherein, The method further includes: • A third detection step (S60) involves detecting that the identifier (200) is located inside the vehicle (100); • A modification step following the third detection step (S60), the modification step involving modifying the communication such that the UWB exchange is performed periodically in a fourth cycle (414), wherein the fourth cycle is longer than the third cycle and / or shorter than the second cycle.

3. The method according to claim 1 or 2, wherein, The method further includes: • After starting the engine of the vehicle (100): o Pause the communication (S70); or o Modify the communication such that the UWB switching is performed periodically in a fifth cycle, wherein the fifth cycle is longer than the fourth cycle and optionally longer than the second cycle; and • Optionally, after suspending (S70) communication, communication is re-established (S71) when the vehicle is traveling at a speed less than or equal to a predetermined speed limit.

4. The method according to claim 3, wherein, The method further includes: • After stopping the engine of the vehicle (100): When communication is suspended, it is re-established using the UWB communication protocol, which includes periodic UWB switching in a third cycle (415); or o When the communication includes periodic UWB switching in a fourth or fifth cycle, the communication is modified such that the UWB switching is performed periodically in a third cycle (415). • Fourth detection step (S80), which involves detecting that the identifier is located at a distance greater than or equal to the predetermined proximity distance (210); and • After the fourth detection step (S80), the communication is paused (S90) and re-established.

5. The method according to any one of the preceding claims, wherein: • The first period is a multiple of the second period; • The second period is a multiple of the third period; and / or • The fourth cycle is a multiple of the third cycle.

6. The method according to any one of the preceding claims, wherein, The portable identifier includes a microcontroller, a BLE component, and a UWB component, wherein the communication initiation includes the microcontroller sending a wake-up signal to the UWB component, and the BLE component is optionally integrated into the microcontroller.

7. The method according to any one of the preceding claims, wherein, The electrical energy source is a battery, preferably a button cell, and / or has a diameter of less than 25 mm and / or a height of less than 8 mm, for example, less than 6 mm.

8. A computer program for a portable identifier and / or vehicle system, comprising instructions that, when executed by a processor, cause the processor to implement the method according to any one of claims 1 to 7.

9. A computer-readable storage medium storing a computer program according to claim 8.

10. A portable identifier and / or vehicle system comprising a storage medium according to claim 9, wherein the portable identifier and / or the system is configured to perform the method according to any one of claims 1 to 7.

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