Use of vehicle UWB systems

Abstract

Use of vehicle UWB (ultra-wideband) wireless systems A method is proposed for using a vehicle UWB system (700) that includes one or more UWB sensors (720) and a registered series of UWB devices (301, 302, 303). The series of UWB devices (301, 302, 303) includes a first UWB device (301) and a second UWB device (303). For each UWB device, the method includes periodically receiving a positioning program including a first positioning and a second positioning via one or more UWB sensors (S10). The method also includes checking the reliability of the execution of the first positioning and second positioning programs (S20), and correcting the programs if the check fails (S30). The method provides an improved use of the vehicle UWB system (700).

Description

Technical Field

[0001] The present disclosure relates to the use of vehicle UWB (Ultra-Wideband wireless) systems.

Background Art

[0002] Currently, there are vehicles equipped with UWB systems including one or more UWB sensors mounted on the vehicle. Usually, such a UWB system can register a series of UWB devices and then determine the positions of each UWB device from the positioning between each UWB device and the UWB sensor of the system. For this purpose, existing methods of using such UWB systems generally involve periodically receiving positioning programs for each UWB device, and these positionings are then used to determine the positions of each UWB device.

[0003] Each positioning is usually programmed over a certain time interval, and during that time interval, the programmed positioning includes UWB transmissions between each of one of the UWB devices and the UWB sensor. If two positionings are programmed to overlap when executed, that is, if the time intervals in which the two positionings are programmed have a non-zero common part, existing methods generally involve canceling the program of one of the two positionings. This reduces the risk of interference between the UWB transmissions of the two positionings. However, such cancellation results in a reduction in the number of positionings finally executed for the UWB device for which one of the positionings has been canceled. As a result, the accuracy and sensitivity of the positioning for that UWB device decrease.

[0004] Therefore, an improved vehicle UWB system is required.

Summary of the Invention

[0005] Therefore, a method is proposed to use a vehicle UWB system that includes one or more UWB sensors and registers a series of UWB devices. The series of UWB devices includes a first UWB device and a second UWB device. For each UWB device, the method includes periodic reception of a positioning program, including a first positioning and a second positioning, by one or more UWB sensors. The first positioning is the positioning of the first UWB device programmed over a first time interval. The second positioning is the positioning of the second UWB device programmed over a second time interval. The first and second time intervals have a non-zero intersection in at least one period. For each of at least one period, the method includes periodic checking the reliability of the execution of the first and second positioning programs and correcting the programs if the check fails.

[0006] Each positioning may include a UWB transmission. The check may include determining the temporal distance between the UWB transmission of the first positioning and the UWB transmission of the second positioning, and checking that each of the determined temporal distances is greater than at least a predetermined temporal distance value.

[0007] Modifying the program if the check fails may include determining the preferred UWB device from the first and second UWB devices, and programming the positioning of the preferred UWB device.

[0008] The given time distance value can be greater than 250 microseconds and / or less than 1 millisecond.

[0009] The positioning program can be completed in less than 10 seconds.

[0010] This method may include detecting a new UWB device and repeatedly receiving and checking programs for the new UWB device.

[0011] This method may include, after a check, performing positioning according to the received program if the check is successful, or according to the modified program if the check fails, and determining the position of each UWB device from the performed positioning.

[0012] A vehicle UWB system is also proposed. The UWB system includes one or more UWB sensors. The system is configured to be used in accordance with this method.

[0013] UWB sensors for such vehicle UWB systems are also proposed. The UWB sensors are configured for use with the system according to this method.

[0014] A computer program is also proposed. The computer program includes program code instructions for executing this method when the program is executed by a processor. [Brief explanation of the drawing]

[0015] A non-limiting embodiment will be described with reference to the following diagram.

[0016] [Figure 1] Figure 1 shows a flowchart of an example of this method.

[0017] [Figure 2] Figure 2 shows an example of multiple positioning programs.

[0018] [Figure 3] Figure 3 shows an example of positioning performed within a time interval consisting of a series of time slots.

[0019] [Figure 4] Figure 4 shows a first embodiment of the implementation of this method.

[0020] [Figure 5] Figure 5 shows a second embodiment of the implementation of this method. [Figure 6] Figure 6 shows a second embodiment of the implementation of this method.

[0021] [Figure 7] Figure 7 shows an example of the use of a vehicle based on positioning programmed by this method.

[0022] [Figure 8] Figure 8 shows an example of the positioning of a UWB device using one or more UWB sensors.

[0023] [Figure 9] Figure 9 shows an example of determining the number of each series of time slots for a UWB device.

[0024] [Figure 10] Figure 10 shows an example of a vehicle UWB system.

Mode for Carrying Out the Invention

[0025] A method of using a vehicle UWB system including one or more UWB sensors and registering a series of UWB devices is proposed. The series of UWB devices includes a first UWB device and a second UWB device. For each UWB device, the method includes periodically receiving a program of positioning including a first positioning and a second positioning by one or more UWB sensors. The first positioning is the positioning of the first UWB device, and the first positioning is programmed over a first time interval. The second positioning is the positioning of the second UWB device, and the second positioning is programmed over a second time interval. In at least one period, the first time interval and the second time interval have a non-zero common part. For each of at least one period (that is, for each period in which the time interval of the first positioning has a non-zero common part with the time interval of the second positioning), the method includes checking the reliability of the execution of the programs of the first positioning and the second positioning, and modifying the program if the check fails.

[0026] This method provides an improved use of the vehicle UWB system.

[0027] Checking the reliability of the execution allows for a prior assessment of whether the first and second positioning can be executed accurately according to the program, and the method includes modifying the program if this check fails (i.e., if the method predicts that the execution is unreliable as a result of the check). The check is particularly important because the first and second positioning are programmed over time intervals that have a non-zero common portion in at least one period. Therefore, the method allows for the detection of future reliability degradation, thereby reducing the risk of interference between the first and second positioning during each period in which the first and second positioning may overlap during execution.

[0028] Furthermore, this check avoids a direct but suboptimal solution that involves systematically canceling the programs for one or both of the first or second positionings if the time interval between the first and second positionings has a non-zero common area. In practice, this method potentially retains the programs for these two positionings as long as the two positionings allow, and only modifies the programs if the check fails. In particular, canceling a positioning reduces the number of programmed positionings for the UWB device involved in the canceled positioning, thereby reducing the accuracy and sensitivity of the positioning. Therefore, this method can improve the overall accuracy and sensitivity of the UWB device's positioning over time.

[0029] This method may include performing positioning following a check. If the check is successful, this method may include performing positioning according to the originally received program. If the check fails, this method may include performing positioning according to the modified program. This method may include, for example, performing positioning excluding canceled positioning.

[0030] Following the execution of positioning, the method may include determining the position of each UWB device based on the performed positioning. Each positioning of a UWB device may include, for example, providing the position of the UWB device relative to the UWB system. For each UWB sensor, positioning may include, for example, measuring the respective distance between the UWB device and the UWB sensor, and determining the position of the UWB device relative to the UWB system based on the measured distances between the UWB device and each UWB sensor. The determined position may change over time. Each positioning may, for example, provide the position of a UWB device relative to the UWB system at a given time, and all positioning performed in relation to that UWB device may provide the change in the position of that UWB device over time.

[0031] Following the positioning, the method may include using the determined relative positions of the UWB devices one or more times. The method may include, for example, activating one or more functions of the vehicle depending on the relative positions of the first and second UWB devices. The functions may include, for example, locking the vehicle when it is determined that the first and second UWB devices are located outside the vehicle, for example, after a predetermined amount of time has elapsed between the time when the first and second UWB devices are determined to be located outside the vehicle. In an example, the functions may include selectively unlocking one or more opening elements of the vehicle (e.g., the driver's door, the passenger's door, or the vehicle trunk) depending on the determined relative positions of the UWB devices. The function may include, for example, unlocking the driver's door and the vehicle trunk when one of the UWB devices (e.g., a first UWB device) is positioned close to the driver's door and another UWB device (e.g., a second UWB device) is positioned close to the trunk (i.e., when two users carrying these devices approach these opening elements, for example, simultaneously or sequentially). In other examples, the function may include unlocking the driver's door and / or passenger door (e.g., when one or more users approach these opening elements), and making one or more adjustments for each user (e.g., adjustment of headrest height or seat position) depending on the user access zone (e.g., depending on the opening element the user approaches). In yet another example, the function may include activating one or more vehicle functions, such as turning on the music or adjusting the rearview mirror, in accordance with the person carrying the UWB device located in the driver's seat (the first UWB device if the person carrying the first UWB device is the driver, or the second UWB device if the person carrying the second UWB device is the driver). The method may include any combination of these examples of functions.

[0032] For each UWB device, the method includes receiving a positioning program using one or more UWB sensors. The program may include programming one or more respective positionings for each UWB device. The received program may be numerical data. For each UWB device and for each positioning associated with the UWB device, the program may include, for example, digital data on a time axis that defines the time-based positioning of the positioning. The time axis can represent a period that has not yet elapsed at the time the program is received. The numerical data defining the positioning may include data specifying the start time of the time interval in which the positioning is programmed and data specifying the end time of that time interval. In addition or alternatively, the numerical data defining each positioning may include numerical data defining each of the UWB transmissions of the positioning. For example, the digital data may specify the start and end times of each UWB transmission of the positioning.

[0033] The received program may be calculated for each period by the UWB system, for example. For example, before each period, the method may include calculating the program for each positioning and, for example, recording the program in the system's memory. For example, for each of a set of UWB devices, the number of positions programmed per period may depend on the UWB device. For example, before the program is first received, the method may communicate with the UWB device to determine the number of positions programmed per period. This communication may include the UWB device transmitting frequency information to the UWB system, and the UWB system calculating the number of positions programmed per period based on the frequency information. The frequency information may be a frequency or duration specific to the UWB device. After this calculation, receiving the program may include reading the program from the system's memory.

[0034] In a received program, each of one or more positionings of the same UWB device may be programmed to be temporally separated. That is, it means that at each given time, only one positioning of the same UWB device is programmed to be performed. For example, each of one or more positionings of the same UWB device may be programmed to be performed consecutively with respect to each other. Each positioning may be programmed to be performed over its respective time interval, i.e., the UWB transmission of a positioning may be performed within its respective time interval. Each UWB transmission of a positioning may start at the same time as or after the start time of its respective time interval, and may end before or at the same time as the end time of its respective time interval. Multiple UWB transmissions of the same positioning may be temporally separated with respect to each time interval. Each time interval of each of one or more positionings of the same UWB device may occur at different times. Two consecutive time intervals may follow each other directly (i.e., the end of one positioning corresponds to the start of a subsequent positioning), or they may be separated by a predetermined period.

[0035] The respective time intervals for positioning of the first UWB device and the second UWB device do not all occur at different times. The first positioning of the first UWB device is programmed over a first time interval that overlaps with the second time interval of the second positioning of the second UWB device. The first and second time intervals have a non-zero intersection. For example, each of the first and second time intervals may include its own start time and end time, the start time of each first time interval may occur before the start time of each second time interval, and the end time of each first time interval may occur after the start time of each second time interval. Alternatively, the start time of each first time interval may occur after the start time of each second time interval, and the end time of each second time interval may occur after the start time of the first time interval. As a further alternative, the respective start times of the first and second time intervals may be combined, and / or the respective end times of the first and second time intervals may be combined.

[0036] "Regularly" means that, at a predetermined duration, the method receives a positioning program for each UWB device, and checks the program if the time interval between two positioning points in the received program has a non-zero common part, and that at regular intervals of this predetermined duration, the method repeats receiving the program for each UWB device and checking the program if there is a non-zero common part. The period represents the duration of this predetermined time interval in which a program for each UWB device is received and the program is checked if there is a non-zero common part.

[0037] For each of at least one period, the method includes checking the reliability of the execution of the programs for the first and second positioning. For other periods, the method does not need to perform the execution reliability check. For example, at the beginning of each period (or before a set of periods and for each period within that set of periods), the method may include checking the non-common parts of the programmed positioning time intervals to determine whether the common part of the time intervals of at least two positionings is non-zero. If this check fails, i.e., if at least two positionings are programmed over time intervals that have a non-zero common part, the method may include checking the reliability of the execution of the programs for these at least two positionings. If this check is successful, the method may not perform the execution reliability check and may directly wait for the next period or proceed to the next period. Alternatively, the method may perform the check in each period, in which case the method does not need to include the check.

[0038] The term “UWB device” (or “identifier”) refers to a moving object identifiable by a vehicle, whose positioning, for example, may or may not permit one or more (specific) actions of the vehicle. The UWB device can be used, for example, to unlock a vehicle and / or start the engine. This method may include, for example, unlocking a vehicle when the UWB device is located near the vehicle, or starting the engine when the UWB device is located inside the vehicle. This method may involve one or more keys and / or smart devices such as mobile phones as one or more UWB devices.

[0039] A positioning program can be performed for a duration equal to, for example, one period, or for a duration equal to several times the period. The program may include determining the time intervals during which each positioning is performed. A positioning program can be performed for less than 10 seconds. A positioning program can be performed for longer than 1 second.

[0040] The duration for which the program is executed can be the time that has not yet elapsed, i.e., the time that will continue to elapse in relation to the program duration and the execution time of this method. The length of the duration can be set or, for example, changed according to the vehicle environment.

[0041] Each UWB transmission may include the transmission of a frame by a UWB device to one or more UWB sensors, or the transmission of a frame by one or more UWB sensors to a UWB device. UWB may refer to a communication protocol as defined, for example, IEEE 802.15.4. For each positioning, one or more positioning programs may include determining the temporal position for each frame transmission. A frame transmission may take 60 to 137 microseconds. Determining the temporal position of a frame transmission may include determining the start time and end time of the frame transmission. The time between the start and end times may be equal to the transmission duration. The transmission duration may depend on the frame length and transmission speed. The relative positions of the start and end times may depend on the frame length and / or transmission speed.

[0042] For each positioning, the time interval in which positioning is programmed may consist of a series of time slots. These time slots may have more or less equal durations. Each slot may have a duration of, for example, 1 millisecond or more and / or 8 milliseconds or less. The duration of a slot may depend on the UWB device associated with the positioning.

[0043] For each UWB device, the program may include programming positioning across each session corresponding to a single period. A session may have a duration corresponding to a predetermined multiple of time, such as one, two, three, or ten times 96 milliseconds. The reference symbols in parentheses shown below refer to Figure 3. Each session (201) can be divided into blocks (202, 203, 204). Each block can be divided into multiple time intervals (205, 206, 207), and positioning can be performed within one of these time intervals. Each time interval can be divided into a series of time slots (210, 211, 212, 215, 216). The UWB transmission of each positioning can be performed within a time slot of a session for a series of UWB devices. For each session, the blocks, the time intervals of each block, and the time slots can be numbered, and for each positioning in a session during a period, the received program may include numerical data that determines the number of the time interval in which positioning is programmed for each block. For each positioning in a session during the period, the received program may also include the number of the time slot in the time interval in which each UWB transmission of the positioning is programmed. The calculation of the program for each UWB device may include determining the number of time slots in each set, the number of time slots in each block, and / or the number of blocks per session for each UWB device.

[0044] "Checking the reliability of the execution of the programs for the first and second positioning" means evaluating a reliability criterion for the results that would be obtained if the first and second positioning were performed according to a given program (in this case, the program first received in this method). The reliability criterion may, in particular, address the presence of potential interference between the UWB transmission associated with the first positioning and the UWB transmission associated with the second positioning. If the UWB transmissions are such that interference is expected, the check "fails," and conversely, if no interference is expected, specifically at least between the first and second positioning, the check "succeeds."

[0045] An execution reliability check can pre-evaluate whether the first and second positioning can be performed correctly according to the program. If the UWB transmissions associated with the first and second positioning are such that interference is expected, this check will actually "fail". In this case, the method anticipates unreliable execution after the check, and the method includes modifying the program. Thus, the method enables the detection of future reliability degradation, thereby reducing the risk of interference between the first and second positioning during each period in which the first and second positioning may overlap during execution.

[0046] In particular, the check avoids a direct but suboptimal solution that involves systematically canceling one or both of the programs for the first or second positioning when the time interval between the first and second positioning has a non-zero common area. This method potentially retains the programs for these two positionings when interference is not expected, and modifies the programs only when interference is expected. Since cancellation reduces the accuracy and sensitivity of positioning, this method can improve the overall accuracy and sensitivity of the UWB device's positioning over time.

[0047] An execution reliability check may consist of checking that the temporal distance between a first positioning UWB transmission and a second positioning UWB transmission is greater than at least a predetermined temporal distance value. Thus, the check may include determining the temporal distance between a first positioning UWB transmission and a second positioning UWB transmission (503, 505, 507 in Figure 6) (excluding, for example, the temporal distance between two consecutive UWB transmissions of the same positioning). For example, each UWB transmission may be provided over its respective time interval, and the time intervals of the first and second positioning UWB transmissions may be consecutive. The temporal distance may be the temporal distance between each time interval of consecutive UWB transmissions. For each UWB transmission, the verification may include determining the temporal distance between the preceding and succeeding UWB transmissions. For each UWB transmission, the temporal distance may correspond to the time elapsed between the end of frame transmission of a preceding UWB transmission and the start of frame transmission of that UWB transmission, or the time elapsed between the end of frame transmission of that UWB transmission and the start of frame transmission of a subsequent UWB transmission. If the temporal distance between each time interval of positioning is greater than a predetermined temporal distance value, the check may succeed. Conversely, if at least one temporal distance between each of the two time intervals of two positionings is less than a predetermined temporal distance value, the check may fail. Alternatively, the two time intervals of two UWB transmissions may not be continuous with each other, i.e., the first time interval of a UWB transmission may have a non-zero intersection with the second time interval of a UWB transmission. In this case, the temporal distance between these two UWB transmissions may be zero, and the check may fail.

[0048] After determining the temporal distances, the check may include verifying that each of the determined temporal distances (except for, for example, the temporal distance between UWB transmissions of the same positioning) is greater than a predetermined temporal distance value. The check may include comparing each of the determined temporal distances with a predetermined temporal distance value. The predetermined temporal distance value can be 250 microseconds or more, for example, more than 250 microseconds strictly. The predetermined temporal distance value can be 1 millisecond or less, for example, less than 1 millisecond strictly.

[0049] If the execution reliability check is successful, this method may include performing positioning according to the received, i.e., the first program. This method does not require modification of the first and second positioning programs. This method may retain the first and second positioning programs.

[0050] If the check fails, this method includes modifying the program. Modifying the program may include canceling one position from the first and second positionings.

[0051] Modifying the program if the check fails may include, for example, randomly canceling one position from the first and second positionings. Modifying the program may also include randomly selecting one position from the first and second positionings and canceling the program for the randomly selected position. The method may then perform positioning according to the modified program, i.e., perform positioning excluding the randomly selected position.

[0052] Alternatively, modifying the program if the check fails may be based on the priority between UWB devices. Modifying the program may include determining the preferred UWB device from a first UWB device and a second UWB device, and programming positioning only for the preferred UWB device. For example, UWB devices within a set of UWB devices may be prioritized by the UWB system. Each UWB device may have a priority over other UWB devices within the set of UWB devices. Determining the preferred UWB device may include comparing the priorities of the first UWB device and the second UWB device. The determination may include determining the UWB device with the higher priority from the first and second UWB devices as the preferred UWB device. Alternatively, one of the UWB devices within a set of UWB devices may be designated as the preferred UWB device, i.e., specified as such in the UWB system. In this case, if the first or second UWB device is the preferred UWB device, this method determines that UWB device to be the preferred UWB device (other UWB devices become secondary UWB devices with respect to the preferred UWB device).

[0053] Next, the method may include programming the positioning of only the preferred UWB device. The method may also include canceling the positioning programs of other UWB devices, i.e., UWB devices that are not determined to be the preferred UWB device among the first and second UWB devices. The positioning program of the preferred UWB device remains unchanged, and the program of the UWB device not determined to be the preferred UWB device contains one less position. Next, the method may include performing a programmed positioning, which includes performing all the positioning initially programmed for the preferred UWB device, and the positioning initially programmed for the UWB device not determined to be the preferred UWB device, with the exception of the positioning whose program was canceled.

[0054] In the example, the positioning may include a third positioning, which is the positioning of a third UWB device programmed over a third time interval. The third time interval may have a non-zero intersection with the first and / or second time intervals. In this case, the method may include checking the programming of the first, second, and third positionings (the time distance between each of the UWB transmissions of the first, second, and third positionings is then determined). If the check fails, the method may include determining a preferred UWB device from the first, second, and third UWB devices, and programming the positioning of the preferred UWB device, i.e., canceling the other positionings from the first, second, and third positionings that are not the positioning of the preferred UWB device. This method can similarly check N programs for overlapping positioning, and if this check fails, it can program only the positioning of the UWB device determined as the priority UWB device.

[0055] The UWB system may register one or more UWB devices other than those in the set of UWB devices associated with this method. This method can detect that one or more other UWB devices are not within the range of the vehicle and can therefore decide not to involve them in the use of this method.

[0056] For example, this method may include detecting a new UWB device. For instance, a new UWB device may be one of one or more other UWB devices registered in the UWB system. A new UWB device may be, for example, a UWB device that was not within the vehicle's range at the start of execution of this method but has since entered the vehicle's range (and therefore been detected by the UWB system). This method may include repeatedly receiving a program and checking for new UWB devices.

[0057] UWB sensors for vehicle UWB systems are also proposed. The UWB sensors are configured to use the system according to the usage method and / or to perform a programming method.

[0058] A UWB sensor may be configured to perform both positioning and radar measurement, and / or to be programmed for this purpose. A UWB sensor may be configured to receive one or more commands (e.g., received from a UWB system) to transmit frames of UWB communication and / or frames of radar measurement. A UWB sensor may be configured to change its settings after transmitting frames of radar measurement and before transmitting frames of UWB communication, or to transmit frames of radar measurement after transmitting frames of UWB communication. A UWB sensor may be configured to make this change in, for example, less than one millisecond.

[0059] A vehicle UWB system is also proposed. The UWB system includes one or more UWB sensors. The system is configured to be used in accordance with this method. The UWB system may be configured to send one or more commands to each UWB sensor after this method has been performed, based on the initial program if the check is successful, or based on the modified program if the check fails. One or more commands may include a request to send a frame of UWB transmission of positioning according to the initial program if the check is successful, or according to the modified program if the check fails.

[0060] A UWB sensor for such vehicle UWB systems is also proposed. The UWB sensor is configured for use with the system according to this method. The UWB sensor is configured to receive one or more commands transmitted by the UWB system and to transmit frames of UWB transmission for positioning according to the transmitted commands, i.e., according to the initial program if the check is successful, and according to the modified program if the check fails.

[0061] A computer program is also proposed. The computer program includes program code instructions for executing this method when the program is executed by a processor. The computer program can be stored in memory. The UWB system may include a processor and / or memory.

[0062] Next, an example will be shown with reference to Figures 1 to 10.

[0063] Figure 1 shows a flowchart of an example of this method. This method uses a vehicle UWB system that includes one or more UWB sensors and registers a series of UWB devices. The series of UWB devices includes a first UWB device and a second UWB device. For each UWB device, this method includes periodically receiving a positioning program (S10) from one or more UWB sensors, which includes a first positioning and a second positioning. The first positioning is the positioning of the first UWB device and is programmed over a first time interval. The second positioning is the positioning of the second UWB device and is programmed over a second time interval. In at least one period, the first time interval and the second time interval have a non-zero intersection. For each of at least one period, the method includes periodically checking the reliability of the execution of the first positioning and second positioning programs (S20), and correcting the programs if the check fails (S30).

[0064] The check (S20) includes determining the temporal distance between the UWB transmission of the first positioning and the UWB transmission of the second positioning (S21), and checking that each of the determined temporal distances is at least greater than a predetermined temporal distance value (S22). If the check fails, modifying the program (S30) includes determining the preferred UWB device from the first UWB device and the second UWB device (S31), and programming the positioning of the preferred UWB device (S32).

[0065] After the check (S20), this method includes performing positioning according to the received program if the check is successful (S40), or performing positioning according to the modified program if the check fails (S30), and determining the position of each UWB device from the performed positioning (S50).

[0066] Figure 2 shows an example of a positioning program. Figure 2 shows the respective blocks 111, 112, and 113 for each UWB device 101, 102, and 103. Each block can last, for example, 288 milliseconds. Each block 111, 112, and 113 contains 18 time intervals 104. Each time interval can last, for example, 16 milliseconds. For each UWB device, the method of use includes positioning the UWB device 121, 122, and 123 using one or more UWB sensors. Positioning 121 relates to UWB device 101, positioning 122 relates to UWB device 102, and positioning 123 relates to UWB device 103. Each positioning includes an active RF section (RF stands for Radio Frequency). The active RF section corresponds to a portion of the time interval in which the positioning includes UWB transmission. In Figure 2, the active FT unit 131 corresponds to positioning related to the UWB device 101, the active FT unit 132 corresponds to positioning related to the UWB device 102, and the active FT unit 133 corresponds to positioning related to the UWB device 103. Figure 2 also shows another active FT unit 134 that corresponds to positioning related to other UWB devices (not shown).

[0067] Figure 3 shows an example of positioning performed within a time interval consisting of a series of time slots. Figure 3 shows session 201 of the UWB device. The session includes, for example, three blocks 202, 203, and 204, each block containing, for example, six time intervals. The usage includes positioning for each of the three blocks. For each block, positioning is performed within one of the block's six time intervals (time interval 205 for block 202, time interval 206 for block 203, and time interval 207 for block 204).

[0068] Here, the positioning performed within time interval 205 (corresponding to 401 in Figure 8) will be described in more detail. Other positioning can be performed in a similar manner. Time interval 205 consists of a series of time slots 210, 211, 212, 213, 214, 215, 216, and 217. The UWB device involved in positioning may be a primary UWB device or a secondary UWB device. Positioning performed within time interval 205 includes UWB transmission between the UWB device and one or more UWB sensors. Each UWB transmission includes transmitting a frame between the UWB device and one or more UWB sensors. The transmission of frames for UWB transmission between the UWB device and one or more UWB sensors is performed within a series of slots (time slots 210, 211, 212, 214, 215, and 216). Frame 220 is transmitted in slot 210, frame 221 in slot 211, and frame 222 in slot 212. Frames 220 and 221 are transmitted from the UWB device to each of one or more UWB sensors. In time slots 212, 213, and 214, each of one or more UWB sensors transmits its respective frame (e.g., frame 222 in slot 212) to the UWB device. Subsequently, frame 225 is transmitted in slot 215, and frame 226 is transmitted in slot 216. Frames 225 and 226 are transmitted from the UWB device to each of one or more UWB sensors. Frames 220, 221, 222, 225, and 226 are transmitted at the start of time slots 210, 211, 212, 215, and 216.

[0069] Figure 4 shows a first embodiment of the implementation of the method. The UWB system registers a series of UWB devices, including a first UWB device 301, a second UWB device 302, and a third UWB device 303. For each UWB sensor, the method includes periodic reception (S10) of a positioning program by one or more UWB sensors. The positioning program received for each UWB device includes positioning for each block of time, and for each positioning, includes a time interval 312 of blocks in which positioning is provided. For example, for the first block 311 of a session for the first UWB device 301, the program includes numerical data indicating that positioning is provided over a first time interval 313 of block 311.

[0070] The positioning of programs received during this period includes overlapping first positioning 314 and second positioning 334. The first positioning 314 is the positioning of the first UWB device 301 programmed over a first time interval, and the second positioning 334 is the positioning of the third UWB device 303 programmed over a second time interval. The first and second time intervals have a non-zero intersection.

[0071] The method includes checking the reliability of the execution of the programs for the first and second positioning (S20). The check includes determining the temporal distance between the UWB transmission of the first positioning and the UWB transmission of the second positioning, and checking that each determined temporal distance is greater than a predetermined temporal distance value. In this first embodiment, the check fails. Therefore, each of the determined temporal distances is not greater than a predetermined temporal distance value. For example, the two UWB transmissions overlap or are not separated by a temporal distance greater than or equal to the predetermined temporal distance value. Next, the method includes making a correction. In this embodiment, modifying the program includes canceling the second positioning 334 that was initially programmed for the third UWB device 303 (S334) (the first UWB device 301 takes precedence over, for example, the third UWB device 303).

[0072] The positioning of programs received during this period includes overlapping third positioning 315, fourth positioning 325, and fifth positioning 335. The third positioning 315 is the positioning of the first UWB device 301 programmed over a third time interval, the fourth positioning 325 is the positioning of the second UWB device 302 programmed over a fourth time interval, and the fifth positioning 335 is the positioning of the third UWB device 303 programmed over a fifth time interval. The third time interval has a non-zero intersection with the fourth and fifth time intervals.

[0073] Therefore, the method includes checking the reliability of the execution of the programs for the third positioning 315, the fourth positioning 325, and the fifth positioning 335 (S20'). The check includes determining the temporal distance between the UWB transmissions of the third positioning 315, the fourth positioning 325, and the fifth positioning 335, and checking that each of the determined temporal distances is at least greater than a predetermined temporal distance value. In this first embodiment, the check fails, so each of the determined temporal distances is not at least greater than a predetermined temporal distance value. For example, the temporal distance between the UWB transmissions of the third positioning 315 and the fourth positioning 325, and the temporal distance between the UWB transmissions of the third positioning 315 and the fifth positioning 335 are all not greater than a predetermined temporal distance value.

[0074] Next, the method includes modifying the program. In this embodiment, modifying the program includes canceling the fourth positioning 325 initially programmed for the second UWB device 302 (S325) and canceling the fifth positioning 335 initially programmed for the third UWB device 303 (S335) (for example, the first UWB device 3014 takes precedence over the second UWB device 302 and the third UWB device 303).

[0075] Figures 5 and 6 show a second embodiment of the implementation of the present method. In this embodiment, the reliability check (S20) of the execution of the first and second positioning programs is successful. Figure 5 shows the UWB transmissions 411, 412, 413, 414 and 415 of the first positioning 314, and the UWB transmissions 431, 432, 433, 434 and 435 of the second positioning 334. Figure 6 shows the temporal distances 501, 502, 503, 504, 505, 506, 507, 508 and 509 between the UWB transmissions 411, 412, 413, 414 and 415 of the first positioning 314 and the UWB transmissions 431, 432, 433, 434 and 435 of the second positioning 334. The decision includes projecting the UWB transmissions 411, 412, 413, 414 of the first positioning 314 and the UWB transmissions 431, 432, 433, 434, 435 of the second positioning 334 onto the same time axis (S510), and determining the temporal distances 501, 502, 503, 504, 505, 506, 507, 508, 509 between each of the projected consecutive transmissions by traversing the time axis. The check includes determining the temporal distance between the UWB transmission of the first positioning and the UWB transmission of the second positioning (i.e., excluding the temporal distance between two UWB transmissions of the same positioning). For example, the check includes determining the temporal distance 503 between two consecutive UWB transmissions 413 and 431, then determining the temporal distance 505 between 432 and 414, and then determining the temporal distance 507 between 415 and 433.

[0076] The check (S20) includes checking that each of the determined time distances 503, 505, and 507 is greater than at least a predetermined time distance value. For example, the method can check that each of the determined time distances 503, 505, and 507 is greater than at least a predetermined time distance value in succession. Alternatively, the method can check that each of the determined time distances 503, 505, and 507 is greater than at least a predetermined time distance value in parallel.

[0077] In this example, the method sequentially determines temporal distances by traversing a time axis and then checks that each of these temporal distances is at least greater than a predetermined temporal distance value. In other embodiments, the method can determine a series of temporal distances in a different way, for example, by determining the temporal distances that separate all UWB transmissions from each other and checking that all of these temporal distances are well above a predetermined temporal distance value.

[0078] In this second embodiment, the check is successful. Thus, each of the determined temporal distances 503, 505, and 507 is at least greater than a predetermined temporal distance value. Next, the method includes performing a first positioning 314 and a second positioning 334 according to the program initially received (S20).

[0079] In this second embodiment as well, the temporal distances between the UWB transmissions of the third positioning 315 and the fourth positioning 325 are all greater than the predetermined temporal distance value. Only the temporal distances between the UWB transmissions of the third positioning 315 and the fifth positioning 335 are not all greater than the predetermined temporal distance value. Therefore, the program execution reliability check (S20') for the third positioning 315 and the fourth positioning 325 succeeds, while the program execution reliability check (S20') for the third positioning 315 and the fifth positioning 335 fails.

[0080] Therefore, the method consists of modifying the program, and in the second embodiment, this modification includes canceling the fifth positioning 335 which was initially programmed only for the third UWB device 303 (S335). Since the third positioning 315 and the fourth positioning 325 can be performed together without the risk of interference between UWB transmissions, modifying the program does not involve canceling the fourth positioning 325.

[0081] Figure 7 shows an example of vehicle use based on positioning programmed using this method.

[0082] While the vehicle engine is running / driving, use includes positioning the UWB device ("identifier") carried by the driver inside the driver's cab (S10). After detecting a stable position of the identifier inside the driver's cab (S20) (for example, after multiple positionings of the identifier at the same position), use includes re-evaluating the placement of the identifier inside the driver's cab (S11). Subsequently, use includes changing the position of the identifier inside the driver's cab (S21) and repositioning the identifier inside the driver's cab (S10). After the engine stops, use again includes detecting a stable position of the identifier inside the driver's cab (S20), re-evaluating the placement of the identifier inside the driver's cab (S11), changing the position of the identifier inside the driver's cab (S21), and repositioning the identifier inside the driver's cab (S10). Furthermore, use includes positioning all identifiers externally after the identifier has been positioned externally (S22) (S15). Use may include one or more radar measurements to check, when locked, that there are no occupants who should remain inside the vehicle after it has been locked.

[0083] [Figure 8] shows an example of positioning of a UWB device using one or more UWB sensors. Positioning includes two transmissions 410 of frames spanning two first time slots from UWB device 400 to each of UWB sensors 401 (corresponding to 205 in Figure 3), 402, and 403. Next, positioning includes each UWB sensor transmitting frames consecutively in their respective time slots (frame 412 to 401, frame 413 to 402, and frame 414 to 403). Subsequently, positioning includes two transmissions 415 of frames spanning two final time slots from UWB device 400 to each of UWB sensors 401, 402, and 403.

[0084] Figure 9 shows an example of determining the number of time slots in each set for a UWB device. This determination can be made based on applying standards, for example, using Table 900. This determination includes determining the time slot duration 901 for the UWB device. For example, the UWB device can communicate its duration to the UWB system. Table 900 contains a set of numbers 902, each applicable to the UWB system. This determination includes determining the number of time slots per time interval based on the set of numbers 902. The number of time slots corresponds to a predetermined set of numbers that is closest to, and greater than, the sum of the number of UWB sensors in the system and a constant (e.g., 4). Table 900 also includes the number of time intervals per block as a function of the time slot duration and the number of time slots in a set. For example, in Table 900, if the time slot duration is 1 millisecond and the number of time slots in a set is 12, the number of time slots per block is 8. This determination may include determining the number of time intervals per block depending on the time slot duration and the number of time slots per time interval.

[0085] Figure 10 shows an example of a vehicle UWB system 700. The UWB system 700 includes a central section 710 and a number of UWB sensors 720 located at the front of the vehicle, the rear of the vehicle, or the driver's cab of the vehicle. The UWB system 700 also includes means for connecting each UWB sensor 720 to the central section 710. Figure 10 also shows a UWB device 730 registered with the UWB system 700. Positioning includes UWB communication 740 between the UWB device 730 and each UWB sensor 720.

Claims

1. A method for using a vehicle UWB system (700) which includes one or more UWB sensors (720) and a registered series of UWB devices (301, 302, 303), wherein the series of UWB devices (301, 302, 303) includes a first UWB device (301) and a second UWB device (303), and the method is For each UWB device, a positioning program including a first positioning (314) and a second positioning (334) is periodically received by one or more UWB sensors (S10), where the first positioning (314) is the positioning of the first UWB device (301) programmed over a first time interval, and the second positioning (334) is the positioning of the second UWB device (303) programmed over a second time interval, and the first time interval and the second time interval have a non-zero common portion in at least one period, and A method comprising periodically checking the reliability of the execution of the programs for the first positioning (314) and the second positioning (334) for each of the at least one of the periods (S20), and correcting the programs if the check fails (S30).

2. Each positioning includes UWB transmission, and the check is, Determining the temporal distance (503, 505, 507) between the UWB transmissions (411, 412, 413, 414, 415) of the first positioning (314) and the UWB transmissions (431, 432, 433, 434, 435) of the second positioning (334) (S21), and The method according to claim 1, further comprising checking (S22) that each of the determined temporal distances (503, 505, 507) is greater than at least a predetermined temporal distance value.

3. Modifying the program if the check fails (S30) Determining the preferred UWB device (301) from the first UWB device (301) and the second UWB device (303) (S31), and, The method according to claim 1 or 2, further comprising programming the positioning of the priority UWB device (301) (S32).

4. The method according to any one of claims 1 to 3, wherein the predetermined value of the temporal distance is greater than 250 microseconds and / or less than 1 millisecond.

5. The method according to any one of claims 1 to 4, wherein the positioning program is performed over a period of time of less than 10 seconds.

6. To detect new UWB devices, and The method according to any one of claims 1 to 5, comprising repeating the reception and check of the program for the new UWB device.

7. After the check, if the verification is successful, the positioning is performed according to the received program (S40); if the check fails, the positioning is performed according to the modified program (S30), and The method according to any one of claims 1 to 6, further comprising determining the position of each of the UWB devices from the positioning performed (S50).

8. A vehicle UWB system (700) comprising one or more UWB sensors (720) and configured to be used in accordance with the method described in any one of claims 1 to 7.

9. A UWB sensor (720) for a vehicle UWB system (700) configured for use in the system according to the method of any one of claims 1 to 7.

10. A computer program, when the program is executed by a processor, comprising program code instructions for performing the method according to any one of claims 1 to 7.

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