Method, apparatus, and storage medium for measuring the location of a car key

Abstract

The present invention provides a method, apparatus, and storage medium for measuring the position of a car key. The method includes the steps of: determining the distance between each of a plurality of position measuring anchors in a car and the key based on distance measuring signals between each of the plurality of position measuring anchors and the key; if a reference anchor is determined from the plurality of position measuring anchors based on the distances between each of the plurality of position measuring anchors and the key, correcting the distance between the position measuring anchors adjacent to the reference anchor and the key and obtaining the corrected distance; performing position measurement calculations on the distance between the reference anchor and the key and the corrected distance to obtain the final position information of the key relative to the car; and performing predetermined operations corresponding to both the final position information of the key relative to the car and control commands transmitted from the key, wherein the reference anchor indicates that the transmission mode of the distance measuring signal to the key is line-of-sight wireless transmission (LOS).

Description

Technical Field

[0001] This application relates to the field of communication technologies, and particularly to a method, apparatus, and storage medium for measuring the position of a vehicle key.

Background Art

[0002] Non-contact operation technologies such as Passive Entry Passive Start (abbreviated as PEPS) enable non-contact operations on a vehicle by a user before the user gets into the vehicle body.

[0003] The non-contact operation on the vehicle by the user is specifically as follows. When the vehicle key carried by the user is within a range at a predetermined distance from the vehicle body, the body control module (abbreviated as BCM) in the vehicle establishes communication with the key. The BCM measures the position of the key and obtains the position information of the key relative to the vehicle. Based on the position information of the key relative to the vehicle and the control command from the key, the BCM executes a predetermined operation corresponding to both the position information of the key and the control command from the key. In the prior art, the method in which the BCM uses the least squares method to perform position calculation on the distance information between the key acquired by the BCM and all the position measurement anchors in the vehicle to obtain the position information of the key relative to the vehicle is the main method for the BCM to measure the position of the key.

[0004] In the prior art, there is a problem that the position measurement in the key position measurement method is not accurate, and as a result, a predetermined operation cannot be executed.

Summary of the Invention

Problems to be Solved by the Invention

[0005] This application provides a method, apparatus, and storage medium for measuring the position of a vehicle key to solve the problem in the prior art that the position measurement in the key position measurement method is not accurate.

Means for Solving the Problems

[0006] In the first aspect, the present application is: After a communication connection is established between the vehicle and the vehicle's key, the distance between each of the multiple position-measuring anchors in the vehicle and the key is determined based on the distance-measuring signal between each of the multiple position-measuring anchors and the key. Based on the distance between each of the plurality of position measuring anchors and the key, if one reference anchor is determined from among the plurality of position measuring anchors that indicates the transmission mode of the distance measuring signal to the key is line-of-sight wireless transmission (LOS), the steps are to correct the distance between the position measuring anchor adjacent to the one reference anchor and the key and obtain the corrected distance. The steps include: calculating the position measurement based on the distance between the one reference anchor and the key and the corrected distance, and obtaining the final position information of the key relative to the vehicle; The present invention provides a method for determining the position of a car key, which includes the step of performing a predetermined operation corresponding to both the final position information of the key relative to the car and a control command transmitted from the key.

[0007] Selectively, one of the position-measuring anchors adjacent to the one reference anchor is the first adjacent anchor. The step of correcting the distance between the position measuring anchor adjacent to the one reference anchor and the key, and obtaining the corrected distance, The steps include: calculating a position measurement based on the distance between each of the one reference anchor and the first adjacent anchor and the key, and the distance between the one reference anchor and the first adjacent anchor, and obtaining first position information of the key relative to the vehicle; The process includes the steps of: correcting the distance between the first adjacent anchor and the key using a predetermined correction value corresponding to the first position information, and obtaining the corrected distance of the first adjacent anchor.

[0008] Selectively, the step of calculating a position measurement with respect to the distance between one reference anchor and the key and the corrected distance, and obtaining the final position information of the key relative to the vehicle, If the first position information is in a predetermined first area, the step of calculating a position measurement with respect to the distance between one reference anchor and the key, the correction distance of the first adjacent anchor and the distance between one reference anchor and the first adjacent anchor, and obtaining the first position measurement result of the key, The step includes determining the first position measurement result as the final position information of the key relative to the vehicle, The first region indicates that the accuracy of the final position of the key is related to a position measuring anchor adjacent to the one reference anchor.

[0009] Selectively, the other position-measuring anchor adjacent to the one reference anchor is the second adjacent anchor. The step of calculating a position measurement based on the distance between the one reference anchor and the key and the corrected distance, and obtaining the final position information of the key relative to the vehicle, is: If the first position information is in a predetermined second area, the step of calculating a position measurement with respect to the distance between each of the one reference anchor and the second adjacent anchor and the key, and the distance between the one reference anchor and the second adjacent anchor, and obtaining the second position information of the key relative to the vehicle, The steps include: calculating the correct distance between the second adjacent anchor and the key using a predetermined correction value corresponding to the second position information, and obtaining the corrected distance of the second adjacent anchor; The steps include: performing position measurement calculations with respect to the distance between the one reference anchor and the key, the correction distance of the second adjacent anchor, and the distance between the one reference anchor and the second adjacent anchor, and obtaining a second position measurement result for the key; The step includes determining the average value of the first position measurement result and the second position measurement result as the final position information of the key relative to the vehicle, The second region indicates that the accuracy of the final position of the key is related to two adjacent position measuring anchors of the one reference anchor.

[0010] Selectively, the step of calculating a position measurement with respect to the distance between each of the one reference anchor and the first adjacent anchor and the key, and the distance between the one reference anchor and the first adjacent anchor, and obtaining first position information of the key relative to the vehicle, is: The first step is to determine a first local coordinate system, with the line connecting the one reference anchor and the first adjacent anchor being the X-axis, and the one reference anchor or the first adjacent anchor being the coordinate origin. A step of determining the first local coordinates of the key in the first local coordinate system based on the distance between each of the one reference anchor and the first adjacent anchor and the key, and the distance between the one reference anchor and the first adjacent anchor. The process includes the step of performing a coordinate system transformation on the first local coordinates to obtain the first coordinates of the key in a predetermined coordinate system of the vehicle, The first coordinates are the first position information of the key relative to the vehicle.

[0011] Selectively, the step of calculating a position measurement with respect to the distance between one reference anchor and the key, the correction distance of the first adjacent anchor, and the distance between one reference anchor and the first adjacent anchor, and obtaining a first position measurement result for the key, The first step is to determine a first local coordinate system, with the line connecting the one reference anchor and the first adjacent anchor being the X-axis, and the one reference anchor or the first adjacent anchor being the coordinate origin. A step of determining the first local modified coordinates of the key in the first local coordinate system based on the distance between the one reference anchor and the key, the modified distance of the first adjacent anchor, and the distance between the one reference anchor and the first adjacent anchor. The process includes the step of performing a coordinate system transformation on the first local modified coordinates to obtain the first modified coordinates of the key in a predetermined coordinate system of the vehicle, The step of calculating a position measurement with respect to the distance between the one reference anchor and the key, the correction distance of the second adjacent anchor, and the distance between the one reference anchor and the second adjacent anchor, and obtaining a second position measurement result for the key, is as follows: The steps include determining a second local coordinate system, where the line connecting the first reference anchor and the second adjacent anchor is the X-axis, and the first reference anchor or the second adjacent anchor is the coordinate origin, A step of determining the second local modified coordinates of the key in the second local coordinate system based on the distance between the one reference anchor and the key, the modified distance of the second adjacent anchor, and the distance between the one reference anchor and the second adjacent anchor. The process includes the step of performing a coordinate system transformation on the second local corrected coordinates to obtain the second corrected coordinates of the key in a predetermined coordinate system of the vehicle.

[0012] Selectively, the step of determining the average value of the first position measurement result and the second position measurement result as the final position information of the key relative to the vehicle is: The process includes the step of calculating the average value of the first corrected coordinate and the second corrected coordinate to obtain the final coordinate of the key in a predetermined coordinate system of the vehicle.

[0013] In a second aspect, the present application provides a control device comprising a collection module, a processing module, and an operation module. The collection module is used to determine the distance between each of the multiple position-measuring anchors in the vehicle and the key, based on distance-measuring signals between each of the multiple position-measuring anchors in the vehicle and the key, after a communication connection has been established between the vehicle and the vehicle key. The processing module is used to obtain the corrected distance when, based on the distance between each of the plurality of position measuring anchors and the key, one reference anchor is determined from among the plurality of position measuring anchors, and the distance between the position measuring anchor adjacent to the one reference anchor and the key is corrected. The processing module is further used to calculate position measurements based on the distance between the one reference anchor and the key and the corrected distance, and to obtain the final position information of the key relative to the vehicle. The operation module is used to perform a predetermined operation that corresponds to both the final position information of the key relative to the vehicle and the control command transmitted from the key. The reference anchor indicates that the transmission mode of the distance measurement signal between it and the key is line-of-sight wireless transmission (LOS).

[0014] In the third aspect, the present application is: A control device comprising a processor and memory is provided. The memory stores executable instructions that can be executed by the processor, When the processor executes an executable instruction stored in the memory, the processor performs the method described above.

[0015] In a fourth aspect, the present invention provides a storage medium in which computer execution instructions are stored, which, when executed by a processor, are used to implement the method described above. [Effects of the Invention]

[0016] The car key position measurement method, apparatus, and storage medium provided in this application determine a reference anchor in LOS transmission from among a plurality of position measurement anchors, and if there is one reference anchor, calculates the position measurement using the distance between the reference anchor and the key in LOS transmission and the corrected distance between the position measurement anchor adjacent to the reference anchor and the key in NLOS transmission, thereby obtaining the final position information of the key relative to the car. This improves the accuracy of key position measurement, and the final position information of the key relative to the car matches the actual position of the key relative to the car. This application solves the problem in the prior art of inaccurate position measurement in key position measurement methods. [Brief explanation of the drawing]

[0017] The drawings attached herein are incorporated into the specification and constitute part of this specification, illustrating embodiments conforming to the present application and are used together with the specification to illustrate the principles of the present application. [Figure 1a] This is a scenario diagram for conventional key position measurement. [Figure 1b] This is a scenario diagram illustrating the transmission of distance measurement signals between a conventional key and a vehicle's positioning anchor. [Figure 2] Figure 1 shows the car key position measurement scenario provided in the embodiment of the present invention. [Figure 3] This is a flowchart of the position measurement calculation provided in the embodiment of the present invention. [Figure 4] Figure 2 shows the car key position measurement scenario provided in the embodiment of the present invention. [Figure 5] This is a schematic diagram of the local coordinate system provided in the embodiment of the present application. [Figure 6] Figure 3 shows the car key position measurement scenario provided in the embodiment of the present invention. [Figure 7] This is flowchart 1 for measuring the position of a car key as provided in the embodiment of the present invention. [Figure 8] This is a schematic diagram illustrating the determination of predetermined correction values ​​provided in the embodiment of the present application. [Figure 9]This is a schematic diagram showing the relationship between the first and second regions provided in the embodiment of the present application and a predetermined region of the anchor. [Figure 10] This is flowchart 2 of the car key position measurement method provided in the embodiment of the present invention. [Figure 11] This is a structural diagram 1 of the control device provided in the embodiment of the present invention. [Figure 12] This is a structural diagram 2 of the control device provided in the embodiment of the present application. Clear embodiments of the present application have already been shown through the above drawings, and a more detailed description will be provided later. These drawings and textual descriptions are not intended to limit the scope of the ideas of the present application in any way, but rather to explain the concepts of the present application to those skilled in the art by reference to specific embodiments. [Modes for carrying out the invention]

[0018] To clarify the purpose, technical solutions, and advantages of the embodiments of this application, the technical solutions will be described clearly and completely below with reference to the drawings relating to the embodiments of this application. Naturally, the embodiments described are only a part of the embodiments of the present invention, and not all embodiments thereof. All other embodiments obtained by those skilled in the art without creative work based on the embodiments of this application shall all fall within the scope of protection of this application.

[0019] Contactless operation technologies such as Passive Entry / Passive Start (PEPS) enable users to operate the vehicle without physical contact before they even get inside.

[0020] Figure 1a is a diagram of a conventional key position measurement scenario. As shown in Figure 1a, a vehicle is typically equipped with position measurement anchors. Examples of position measurement anchors on a vehicle include UWB anchors such as UWB1, UWB2, UWB3, UWB4, UWB5, UWB6, and UWB7 shown in Figure 1a. As shown in Figure 1a, UWB1, UWB2, UWB3, and UWB4 are all located outside the vehicle body. For example, UWB1 and UWB4 are located at both ends of the front bumper, and UWB2 and UWB3 are located at both ends of the rear bumper. UWB5, UWB6, and UWB7 are all located inside the vehicle body. A body control module (BCM) 12 is also equipped in the vehicle. The BCM 12 continuously broadcasts a BLE broadcast signal via the Bluetooth® (Bluetooth Low Energy, BLE) module in the BCM 12. The car key 11 detects the car's BLE broadcast signal in real time.

[0021] The specific process for contactless operation of the user's vehicle is as follows: When key 11 detects and identifies that the Received Signal Strength Indication (RSSI) of the vehicle's BLE broadcast signal has reached a predetermined communication threshold, key 11 sends a communication connection request to the vehicle's BCM 12. BCM 12 responds to the communication connection request sent from key 11 to establish a communication connection between the vehicle and the corresponding key 11, and establishes communication with key 11 after authentication is successful. BCM 12 uses the BLE RSSI between BCM 12 and key 11 as a distance measurement signal to continuously measure the distance to key 11 and obtain the Bluetooth® distance measurement distance of key 11 to the vehicle. When the Bluetooth® distance measurement distance is below a first distance threshold, the BCM 12 controls the positioning devices at multiple positioning anchors in the vehicle, activates the distance measurement function of each positioning device, and converts the Bluetooth® distance measurement mode to an Ultra Wide Band (UWB) Time of Flight (ToF) distance measurement mode by the positioning device. The positioning device may be a UWB device equipped with a UWB chip or UWB module. The positioning device and the BCM 12 may be connected via a bus.

[0022] The car key 11 may be a physical key or a virtual key on a user terminal.

[0023] After the BCM 12 converts the Bluetooth® RSSI distance measurement mode to the UWB ToF distance measurement mode, the BCM 12 measures the position of the key 11 as follows: Based on the distance measurement signals between each position measurement device and the key 11, the BCM 12 determines distance information between the position measurement anchor corresponding to each position measurement device and the key 11. To measure the position of the key 11, the BCM 12 calculates the position using the least squares method for the multiple distance pieces determined and obtains the position information of the key 11 relative to the vehicle. The position information of the key 11 relative to the vehicle may be the coordinates of the key 11 in a predetermined coordinate system of the vehicle. Based on the position information of the key relative to the vehicle and the control commands transmitted from the key, the BCM 12 performs predetermined operations that correspond to both the position information of the key and the control commands from the key. Predetermined operations include controlling the vehicle so that it automatically drives out of the garage and reaches a predetermined location.

[0024] As shown in Figure 1b, the key 11 is located outside the vehicle body, and the transmission modes of the distance measurement signal between the key 11 and the position measurement anchor on the vehicle body include line-of-sight (LOS) and non-line-of-sight (NLOS) transmission. Because there is no straight path for the distance measurement signal between the key 11 and the position measurement anchor inside the vehicle body due to shielding by the vehicle body, the transmission mode of the distance measurement signal is NLOS transmission. NLOS transmission of the distance measurement signal between the key 11 and the position measurement anchor is affected by reflection and / or diffraction from a reflector during transmission, indicating that there is no straight path for the transmission of the distance measurement signal due to insufficient line-of-sight conditions. Examples of reflectors include the metal or non-metallic body of the vehicle. When the distance measurement signal is reflected and / or diffracted from a reflector, the RSSI of the distance measurement signal is attenuated due to factors such as the surface conductivity, roughness, and reflectivity of the reflector. Because the distance measurement signal is reflected and / or diffracted by a reflector during transmission, the distance between the key 11 and the position measurement anchor determined based on the distance measurement signal is often greater than the actual distance between the key 11 and the position measurement anchor. Therefore, the distance information between the key 11 and all position measurement anchors in the vehicle will contain inaccurate distance information.

[0025] In the embodiments of this application, NLOS is also called NLOS transmission and LOS is also called LOS transmission. The actual distance between two points is the straight-line distance between the two points. For example, the actual distance between key 11 and position measuring anchor UWB1 is, i.e., the straight-line distance between key 11 and UWB1.

[0026] The accuracy of the results calculated using the least squares method is closely related to the amount and accuracy of the data used in the calculation. Therefore, in order to ensure the amount of data used in the least squares calculation, conventional key position measurement methods use distance information between key 11 and all position measurement anchors for calculating the position of key 11. As a result, there is a large deviation between the obtained position information of key 11 relative to the vehicle and the actual position of key 11 relative to the vehicle. Consequently, conventional key position measurement methods have the problem of inaccurate position measurement. Furthermore, a discrepancy occurs between the key position obtained from the vehicle calculation and the actual position of the key. As a result, even if key 11 transmits a control command corresponding to a predetermined operation at a position corresponding to a predetermined operation, the predetermined operation cannot be executed by BCM 12, which affects the user's experience of using the vehicle.

[0027] In Scenario 1 shown in Figure 1b, when the key 11 is outside the vehicle body and on one side of the door, the transmission of distance measurement signals between the key 11 and at least two of the position measurement anchors UWB1, UWB4, UWB2, and UWB3, which are positioned at both ends of the front and rear bumpers of the car, is not reflected or diffracted by the reflector, or the transmission mode of the distance measurement signals between the key 11 and at least two of the position measurement anchors is LOS transmission. Similarly, in Scenario 2 shown in Figure 1b, when the key is outside the vehicle body and on either the front or rear side, the transmission mode of the distance measurement signals between the key 11 and at least two of the position measurement anchors UWB1, UWB4, UWB2, and UWB3, which are positioned at both ends of the front and rear bumpers of the car, is LOS transmission. In addition, in both Scenario 1 and Scenario 2 shown in Figure 1b, the two position measurement anchors in LOS transmission are adjacent to each other.

[0028] As shown in Figure 1b, if the four position measuring anchors UWB1, UWB4, UWB2, and UWB3 are located at both ends of the front and rear bumpers of the car, and two of the position measuring anchors on one side of the front (e.g., UWB1 and UWB4) are not aligned with the vertex of the outer edge line of the front (e.g., point K1), and two of the position measuring anchors on one side of the door (e.g., UWB3 and UWB4) are not aligned with the vertex of the outer edge of the car body on that side (e.g., K2), then when key 11 is in the intersection region of the front and door outer edge as shown in Scenario 3 in Figure 1b, the distance measuring signal between key 11 and the nearest position measuring anchor is a signal transmitted via LOS. However, the distance measurement signals between key 11 and the remaining three position-measuring anchors (e.g., UWB1, UWB2, UWB3) are reflected or diffracted by the reflectors, meaning that the transmission mode of the distance measurement signals between key 11 and each of UWB1, UWB2, and UWB3 is NLOS transmission.

[0029] When the transmission mode of the distance measurement signal between the key and at least two position measurement anchors in the vehicle is LOS transmission, the accurate position measurement of the key can be achieved by performing position measurement calculations on the distance information of the two position measurement anchors whose distance measurement signal transmission mode is LOS transmission. Similarly, when the transmission mode of the distance measurement signal between the key and one position measurement anchor in the vehicle is LOS transmission, the accurate position measurement of the key can be achieved by performing position measurement calculations on the distance information of the position measurement anchor corresponding to LOS transmission and the distance information of the position measurement anchor corresponding to modified NLOS transmission.

[0030] In view of this, the present invention provides a method for measuring the position of a car key, and improves the accuracy of measuring the position of a car key by performing position measurement calculations on distance information of a position measurement anchor corresponding to LOS transmission and corrected distance information of a position measurement anchor corresponding to NLOS transmission.

[0031] The method for measuring the position of a car key provided in this application will be described below with reference to several embodiments.

[0032] Figure 2 is a car key position measurement scenario provided in an embodiment of the present invention. As shown in Figure 2, the car is equipped with multiple position measurement anchors, including UWB1, UWB2, UWB3, and UWB4 shown in Figure 2. For example, UWB1 and UWB4 are located at both ends of the car's front bumper, and UWB2 and UWB3 are located at both ends of the rear bumper. The four position-measuring anchors UWB1, UWB4, UWB2, and UWB3, positioned at both ends of the front and rear bumpers of the car, are configured such that two of the position-measuring anchors on one side of the front (e.g., UWB1 and UWB4) are not aligned with the vertex of the front outer edge line (e.g., point K1), two of the position-measuring anchors on one side of the rear (e.g., UWB2 and UWB3) are not aligned with the vertex of the rear outer edge line (e.g., point K3), and two of the position-measuring anchors on one side of the door (e.g., UWB3 and UWB4) are not aligned with the vertex of the outer edge line on that side of the car body (e.g., K2). A position-measuring device is provided at each position-measuring anchor, and the position-measuring device can determine the distance between the position-measuring anchor and the key 11, or the position-measuring anchor is an anchor with a position-measuring function. The position-measuring device may be a UWB device equipped with a UWB chip or a UWB module. The location measuring device may be a location measuring device equipped with a BLE module or BLE chip. The car is equipped with a control device 21 equipped with a BLE module. The car key 11 similarly includes a UWB chip or UWB module. The car key 11 further includes a BLE module or BLE chip. The car key 11 may be a physical key or a virtual key on a user terminal. Examples of user terminals include mobile phones and tablet computers.

[0033] The control device 21 continuously broadcasts a BLE broadcast signal via the BLE module. The car key 11 detects the car's BLE broadcast signal in real time. When the key 11 detects and identifies that the RSSI of the car's BLE broadcast signal has reached a predetermined communication threshold, the key 11 sends a communication connection request to the car's control device 21. The control device 21 responds to the communication connection request sent from the key 11 so that a communication connection between the car and the key 11 is established, and establishes communication with the key 11 after authentication is successful. Based on the BLE distance measurement signal between the control device 21 and the key 11, the control device 21 continuously measures the distance to the key 11 and obtains the Bluetooth® distance measurement distance of the key 11 relative to the car. If the Bluetooth® distance measurement distance is less than or equal to a first distance threshold, the control device 21 controls the position measuring devices at multiple position measuring anchors in the car and activates the distance measuring function of each position measuring device. If the position measuring device is a UWB device, the control device 21 converts the Bluetooth® distance measuring mode used by the control device 21 to the UWB distance measuring mode used by the position measuring device. The distance measuring signal between the position measuring device and the key 11 becomes the distance measuring signal between the position measuring anchor corresponding to the position measuring device and the key 11.

[0034] After the control device 21 converts the Bluetooth® distance measurement mode to the UWB distance measurement mode, the control device 21 performs the position measurement of the key 11 as follows:

[0035] The control device 21 determines the distance between each of the multiple position-measuring anchors in the vehicle and the key 11 based on the distance-measuring signals between each of the multiple position-measuring anchors and the key 11.

[0036] When the distribution scenario of key 11 and the car is similar to scenario 1 or scenario 2 in Figure 2, the control device 21 can determine at least two reference anchors from among the multiple position measuring anchors based on the distance between each of the multiple position measuring anchors and key 11. The control device 21 can obtain the final position information of key 11 relative to the car by performing position measurement calculations on the distance between each of the two determined adjacent reference anchors and key 11.

[0037] The reference anchor indicates that the transmission mode for the distance measurement signal between it and key 11 is line-of-sight wireless transmission (LOS).

[0038] When the distribution scenario of key 11 and the car is similar to scenario 3 in Figure 2, the distance measurement signal between key 11 and the nearest position measuring anchor (e.g., UWB1) is a signal transmitted via LOS. However, the distance measurement signals between key 11 and the remaining three position measuring anchors (e.g., UWB2, UWB3, UWB4) are reflected or diffracted by reflectors, meaning that the transmission mode of the distance measurement signals between key 11 and each of UWB2, UWB3, and UWB4 is NLOS transmission. The reflector may be the ground, or a metal or non-metallic car body. Based on the distance between each of the multiple position measuring anchors and key 11, the control device 21 can determine one reference anchor (e.g., UWB1) from among the multiple position measuring anchors. The control device 21 can correct the distance between the position measuring anchors adjacent to this reference anchor (e.g., UWB2 and / or UWB4) and key 11, and obtain the corrected distance. The control device 21 calculates the position measurement based on the distance between this one reference anchor and the key 11, and the correction distance corresponding to the position measuring anchor adjacent to this one reference anchor, and obtains the final position information of the key 11 relative to the vehicle.

[0039] The control device 21 performs a predetermined operation corresponding to both the final position information of the key 11 and the control command transmitted from the key 11, based on the final position information of the key 11 relative to the vehicle and the control command transmitted from the key 11. An example of a predetermined operation is an operation to control the vehicle so that it automatically drives out of the garage and reaches a predetermined position.

[0040] For example, the control device 21 can determine a reference anchor from among the multiple position measuring anchors based on the distance between each of the multiple position measuring anchors and the key 11, according to the following steps I to III.

[0041] In step I, the control device 21 obtains the Received Signal Strength Indicator (RSSI) corresponding to each of the multiple position measuring anchors from the key 11, and / or obtains the status identifier of the corresponding position measuring anchor from the position measuring device of each of the multiple position measuring anchors. The status identifier is either a valid identifier indicating that the distance measuring signal used for measuring the distance between the position measuring anchor and the key is valid, or an invalid identifier indicating that the distance measuring signal used for measuring the distance between the position measuring anchor and the key is invalid. Examples of a valid identifier include 1 or valid. Examples of an invalid identifier include 0 or invalid. The control device 21 also obtains the Signal Time of Flight (ToF) corresponding to each of the multiple position measuring anchors from the key 11.

[0042] In step II, the control device 21 determines the effective distance between each of the multiple position measuring anchors and the key 11 from among the distances between each of the multiple position measuring anchors and the key 11, whichever is greater than the signal strength threshold RSSI, and / or determines the effective distance between each of the acquired status identifiers of the multiple position measuring anchors and the key, whichever is corresponding to a valid identifier.

[0043] In step III, the control device 21 either determines a position measuring anchor corresponding to the effective distance as a reference anchor, or determines a position measuring anchor whose Time of Flight (ToF) satisfies predetermined conditions as a reference anchor. For example, the control device 21 determines the position measuring anchor with the smallest ToF from among the ToFs corresponding to each of a plurality of position measuring anchors as the reference anchor.

[0044] control device 21 The control unit determines an effective distance from the distance between each of the multiple position measuring anchors and the key 11 based on at least one of ToF, RSSI, or the status identifier of the position measuring anchor, and then determines a reference anchor based on the effective distance. This improves the accuracy of the reference anchor determination and ensures the validity of the determined reference anchor. 21 This system determines the reference anchor based on the ToF (Time of Flight) corresponding to each of the multiple position-measuring anchors, thereby improving the accuracy of the reference anchor determination and ensuring that the determined reference anchor is valid.

[0045] Optionally, the position measuring device may be a Bluetooth® position measuring device. After the distance measuring function of the Bluetooth® position measuring device is activated, the control device 21 measures the position of the key 11 as follows: Based on the distance measuring signals (such as Bluetooth® distance measuring signals) between each of the multiple position measuring anchors in the vehicle and the key 11, the control device 21 determines the distance between each of the multiple position measuring anchors and the key 11. If the control device 21 determines at least two reference anchors from among the multiple position measuring anchors based on the distance between each of the multiple position measuring anchors and the key 11, it calculates the position measurement for the distance between each of the two determined adjacent reference anchors and the key 11, and obtains the final position information of the key 11 relative to the vehicle. If the control device 21 determines one reference anchor from among the multiple position measuring anchors based on the distance between each of the multiple position measuring anchors and the key 11, it corrects the distance between the position measuring anchor adjacent to this one reference anchor and the key 11, and obtains the corrected distance. The control device 21 calculates the position measurement based on the distance between this one reference anchor and the key 11, and the correction distance corresponding to the position measuring anchor adjacent to this one reference anchor, and obtains the final position information of the key 11 relative to the vehicle.

[0046] Generally, for short-range distance measurement, the accuracy of UWB distance measurement is higher than that of Bluetooth® distance measurement; therefore, the position measuring device is preferably a UWB device in UWB distance measurement mode.

[0047] The car key position measurement method provided in the embodiment of the present invention determines a reference anchor in LOS transmission from among a plurality of position measurement anchors. When the number of reference anchors is set to include at least two anchors, the position measurement is calculated based on the distance between each of the two adjacent reference anchors and the key to obtain the final position information of the key relative to the car. However, when there is only one reference anchor, the position measurement is calculated based on the distance between the reference anchor and the key in LOS transmission and the corrected distance between the adjacent position measurement anchor and the key in NLOS transmission to obtain the final position information of the key relative to the car. This improves the accuracy of key position measurement, ensuring that the final position information of the key relative to the car matches the actual position of the key relative to the car. The car key position measurement method provided in the embodiment of the present invention reduces, and preferably eliminates, the adverse effects of inaccurate distance information determined by the distance measurement signal in NLOS transmission on the accuracy of key position measurement, thus solving the problem in the prior art of inaccurate position measurement in key position measurement methods.

[0048] The method for measuring the position of a car key provided in this application will be described in detail below with reference to Figures 3 to 10. Figure 3 is a flowchart of the position measurement calculation provided in the embodiment of this application. Figure 4 is a car key position measurement scenario 2 provided in the embodiment of this application. Figure 5 is a schematic diagram of the local coordinate system provided in the embodiment of this application. Figure 6 is a car key position measurement scenario 3 provided in the embodiment of this application. Figure 7 is a flowchart 1 of the car key position measurement provided in the embodiment of this application. Figure 8 is a schematic diagram of the determination of a predetermined correction value provided in the embodiment of this application. Figure 9 is a schematic diagram of the relationship between the first and second regions and a predetermined region of the anchor provided in the embodiment of this application. Figure 10 is a flowchart 2 of the car key position measurement provided in the embodiment of this application. The implementing body of the car key position measurement method provided in the embodiment of this application may be the control device 21 in the embodiment shown in Figure 2. The following will be described illustratively using the case where the implementing body is the control device 21 as an example.

[0049] After a communication connection is established between the vehicle and the vehicle key 11, and the distance measurement operation of the position measuring device at multiple position measuring anchors in the vehicle is activated, the control device 21 acquires distance measuring signals between each of the multiple position measuring anchors in the vehicle and the key 11. Based on the distance measuring signals between each of the multiple position measuring anchors in the vehicle and the key 11, the control device 21 determines the distance between each of the multiple position measuring anchors and the key 11. If the distribution scenario of the key 11 and the vehicle is a scenario similar to scenario 1 or scenario 2 in Figure 2, or the scenario shown in Figure 4, the control device 21 can determine at least two reference anchors from among the multiple position measuring anchors based on the distance between each of the multiple position measuring anchors and the key 11 in order to position the key 11. If the distribution scenario of the key 11 and the vehicle is a scenario similar to scenario 3 in Figure 2, or the scenario shown in Figure 6, the control device 21 can determine one reference anchor from among the multiple position measuring anchors based on the distance between each of the multiple position measuring anchors and the key 11 in order to position the key 11.

[0050] The following describes the method for measuring the position of key 11 when there are at least two determined reference anchors, and the method for measuring the position of key 11 when there is one determined reference anchor.

[0051] (1) The method for measuring the position of key 11 when there are at least two determined reference anchors is as follows.

[0052] When the control device 21 determines at least two reference anchors from among the multiple position measuring anchors based on the distance between each of the multiple position measuring anchors and the key 11, it calculates the position measurement for the distance between each of the two determined adjacent reference anchors and the key 11 according to the method shown in S101 to S102 of Figure 3, and obtains the final position information of the key 11 relative to the vehicle.

[0053] In S101, the control device 21 determines the third local coordinates of the key 11 in a third local coordinate system corresponding to the two determined adjacent reference anchors, based on the distance between each of the two determined adjacent reference anchors and the key 11.

[0054] Exemplary, the control device 21 determines a third local coordinate system by setting the line connecting the two determined adjacent reference anchors as the X-axis and one of the reference anchors on the X-axis as the coordinate origin. Optionally, if the key 11 and the reference anchors are not collinear, the local coordinate system determined by the control device 21 may be such that the Y-axis coordinate value of the key 11 in the local coordinate system is a negative number for the same vehicle. Optionally, if the key 11 and the reference anchors are not collinear, the local coordinate system determined by the control device 21 may be such that the Y-axis coordinate value of the key 11 in the local coordinate system is a positive number for the same vehicle. Based on the distance between each of the two determined adjacent reference anchors and the key 11, the control device 21 determines a third local coordinate of the key 11 in the third local coordinate system corresponding to the two determined adjacent reference anchors. The third local coordinate of the key 11 indicates the position of the key 11 relative to the two determined adjacent reference anchors.

[0055] The control device 21 accurately determines the position of the key 11 relative to two adjacent reference anchors, each of which has a distance measurement signal transmission mode of LOS, based on the distance between the key 11 and the two adjacent reference anchors. To ensure the accuracy of the determined position of the key 11, the control device 21 performs a coordinate system transformation process on the local coordinates of the key 11 according to the method shown in S102, making it easy to obtain the coordinates of the key 11 in a predetermined coordinate system of the vehicle.

[0056] In S102, the control device 21 performs a coordinate system transformation process on the third local coordinates to obtain the final coordinates of the key 11 in the predetermined coordinate system of the vehicle. The final position information of the key 11 relative to the vehicle includes the final coordinates of the key 11 in the predetermined coordinate system of the vehicle.

[0057] Exemplarily, the control device 21 determines a coordinate transformation coefficient θ corresponding to the coordinate origin of the local coordinate system to which the third local coordinate (x l3 , y l3 ) belongs.

[0058] The control device 21 uses the transformation matrix JPEG2026509759000020.jpg34116 to transform the third local coordinate (x l3 , y l3 ) into the rotated coordinate (x r3 , y r3 ). The control device 21, based on the global coordinates (x 03 , y 03 ) of the position measurement anchor corresponding to the coordinate origin of the third local coordinate system in a predetermined coordinate system of the vehicle, determines the final coordinates (x g3 = x r3 + x 03 and y g3 = y r3 + y 03 ) of the key 11 in a predetermined coordinate system of the vehicle according to the formula, and determines the final coordinates (x g3 , y g3 ) of the key 11 in a predetermined coordinate system of the vehicle. [[ID=XXX]] [[ID=XXX]]

[0059] [[ID=XXX]] In step S102, the conversion from the coordinates of the key 11 in the local coordinate system to the coordinates of the key 11 in the predetermined coordinate system is realized, and the final position information of the key 11 with respect to the vehicle is obtained. [[ID=XXX]] [[ID=XXX]]

[0060] [[ID=XXX]] After the control device 21 obtains the final position information of the key 11 with respect to the vehicle according to steps S101 to S102, the control device 21 executes a predetermined operation corresponding to both the final position information of the key 11 with respect to the vehicle and the control command transmitted from the key 11. [[ID=XXX]] [[ID=XXX]]

[0061] [[ID=XXX]] Hereinafter, the calculation of the position measurement shown in steps S101 to S102 will be further described using other examples. [[ID=XXX]] [[ID=XXX]]

[0062] [[ID=XXX]] It should be noted that some of the <0000xxx> tags seem to be in an incorrect format or might be related to some specific internal references in a system that are not fully clear from the provided text. The translation has been done as accurately as possible while maintaining their original form.Assuming that the distribution of key A and vehicle A is as shown in Figure 4, the predetermined coordinate system of vehicle A may be the coordinate system shown in Figure 4, that is, the forward direction of the vehicle's centerline is the positive direction of the Y-axis, the direction to the driver's right is the positive direction of the X-axis, and the intersection of the X-axis and Y-axis is at the leading edge vertex of the vehicle's front along the central axis (point K1 shown in Figure 2). The four position measuring anchors UWB1, UWB2, UWB3, and UWB4 in vehicle A are arranged to be the same as the four position measuring anchors UWB1, UWB2, UWB3, and UWB4 shown in Figure 2. When the four position measuring anchors UWB1, UWB2, UWB3, and UWB4 in vehicle A are the coordinate origins of the local coordinate system, the corresponding coordinate transformation coefficients are θ1, θ2, θ3, and θ4, respectively. The values ​​of θ1, θ2, θ3, and θ4 may be 270°, 0°, 90°, and 180°, respectively.

[0063] The control device 21 determines two adjacent reference anchors, UWB3 and UWB4, from the distances between each of the four position measuring anchors UWB1, UWB2, UWB3, and UWB4 in vehicle A shown in Figure 4 and key A. The coordinates of the two adjacent reference anchors UWB3 and UWB4 in a predetermined coordinate system of vehicle A are (x 03A ,y 03A ) and (x 04A ,y 04A )

[0064] The control device 21 determines the third local coordinate system shown in Figure 5, and the coordinate transformation coefficient θ3 corresponding to the coordinate origin of the third local coordinate system shown in Figure 5, using the line connecting the reference anchors UWB3 and UWB4 as the X-axis and UWB3 as the coordinate origin. The third local coordinate system is the local coordinate system corresponding to the reference anchors UWB3 and UWB4. In the third local coordinate system, the coordinate value of the Y-axis of key A is a negative number. The control device 21 determines the distances d3 and d4 between each of the reference anchors UWB3 and UWB4 and key A, and the distance h between the reference anchors UWB3 and UWB4. 34 Based on this, the key in the third local coordinate system shown in Figure 5 A The third local coordinate (x l3A ,y l3A The following will be determined: As shown in Figure 5, if the vertical distance from key A to the X-axis is dy and the vertical distance from key A to the Y-axis is dx, then the third local coordinate (x) of key A in the third local coordinate system shown in Figure 5 is l3A ,y l3A ) = (dx, -dy). Here, dx and dy are determined by the law of cosines (d4) of the control device 21. 2 =(d3) 2 +( h 34 ) 2 -2 × d3 × h 34 According to ×cosα, By determining JPEG2026509759000021.jpg2091, d x =d3×cosα;d y It is determined that = d3 × sinα is determined.

[0065] The control device 21 is a transformation matrix Using JPEG2026509759000022.jpg21123, the third local coordinate (x l3A ,y l3A ) rotate coordinate (x r3A ,y r3A The control device 21 converts the global coordinates (x) of the vehicle A of the position measuring anchor corresponding to the coordinate origin of the third local coordinate system to a predetermined coordinate system. 03A ,y 03A Based on x g3A =x r3A +x 03A and y g3A =y r3A +y 03A In the equation, the final coordinates (x) of key A in the given coordinate system of car A g3A ,y g3A Determine the final coordinates (x) of key A in the given coordinate system of car A. g3A ,y g3A This, in other words, represents the final position information of key A relative to car A.

[0066] (ii) The method for measuring the position of key 11 when there is one determined reference anchor is as follows.

[0067] If the distribution of key 11 and the car is as shown in Scenario 3 of Figure 2, the transmission mode of the distance measurement signal between key 11 and UWB1 is LOS. However, the transmission mode of the distance measurement signal between key 11 and each of UWB2, UWB3, and UWB4 is NLOS. Based on the distance between key 11 and each of the four position measurement anchors UWB1, UWB2, UWB3, and UWB4, the control device 21 determines UWB1 as a reference anchor.

[0068] The method for measuring the position of key 11, as shown in Scenario 3 of Figure 2, is shown in Figure 7.

[0069] In S201, after a communication connection is established between the vehicle and the vehicle key 11, the control device 21 determines the distance between each of the multiple position measuring anchors in the vehicle and the key 11 based on the distance measuring signals between each of the multiple position measuring anchors and the key 11.

[0070] In S202, the control device 21 determines one reference anchor from among the multiple position measuring anchors based on the distance between each of the multiple position measuring anchors and the key 11. If a reference anchor is determined from among the multiple position measuring anchors, the control device 21 corrects the distance between the position measuring anchor adjacent to this reference anchor and the key 11, and obtains the corrected distance.

[0071] When the control device 21 determines one reference anchor from among the multiple position measuring anchors based on the distance between each of the multiple position measuring anchors and the key 11, it indicates that the transmission mode of the distance measuring signal between the position measuring anchor adjacent to this reference anchor and the key 11 is NLOS. The fact that the transmission mode of the distance measuring signal between the position measuring anchor and the key 11 is NLOS indicates that the distance measuring signal between the position measuring anchor and the key 11 is reflected or radiated by the reflector during transmission, and the distance between the position measuring anchor and the key 11 determined based on the distance measuring signal reflected or radiated by the reflector is greater than the actual distance between the position measuring anchor and the key 11. In order to use the distance determined by the distance measuring signal in the NLOS transmission between the position measuring anchor and the key 11 for position measurement of the key 11, it is necessary to correct the distance determined by the distance measuring signal in this NLOS transmission to obtain the accurate distance between the position measuring anchor and the key 11, and in this way the position measurement accuracy of the key 11 can be improved. In contrast, the embodiment of the present invention proposes a method for correcting the distance determined by the distance measurement signal in NLOS transmission using a predetermined correction value.

[0072] Illustratively, Figure 8 is a schematic diagram of the determination of a predetermined correction value provided in an embodiment of the present invention. As shown in Figure 8, an anchor preset area (e.g., a 5m x 5m area) is set in advance for each of the four position measuring anchors (e.g., UWB1, UWB2, UWB3, UWB4) in the vehicle, and an equidistant grid (e.g., a 25cm x 25cm grid) is set within the anchor preset area. The identifier of each grid can be represented as (i,j), where i represents the grid number in the X-axis direction in a predetermined coordinate system of the vehicle, and j represents the grid number in the Y-axis direction in a predetermined coordinate system of the vehicle. Coordinate point (X) within grid (i,j) i ,Y j ) is β i1 ≤X i ≤β i2 and β j1 ≦Y j ≤β j2The following conditions are met. For each grid in each anchor preset region, the key 11 is placed at the center of the grid, and the distance determined by the distance measurement signal in the NLOS transmission between each position measuring anchor adjacent to the position measuring anchor corresponding to the anchor preset region and the key is obtained as the capture distance, the distance between the center of the grid and the position measuring anchor adjacent to the position measuring anchor corresponding to the anchor preset region is calculated as the theoretical distance, and the difference between the capture distance and the theoretical distance is determined as the interpolation value corresponding to the grid. Optionally, the shape of the anchor preset region may be a sector, a circle, or any other irregular shape.

[0073] As shown in Figure 8, the position-measuring anchors adjacent to UWB1 include UWB2 and UWB4. Key 11 (e.g., Key A in Figure 8) is placed at the center position of grid (i,j) in the anchor preset region corresponding to UWB1. The capture distance d21 between Key A and UWB2 is obtained, the theoretical distance d22 between Key A and UWB2 is calculated, and the interpolation value Δd2(i,j)=d21-d22 for the adjacent position-measuring anchor UWB2 corresponding to grid (i,j) is determined. Similarly, the capture distance d41 between Key A and UWB4 is obtained, the theoretical distance d42 between Key A and UWB4 is calculated, and the interpolation value Δd4(i,j)=d41-d42 for the adjacent position-measuring anchor UWB4 corresponding to grid (i,j) is determined.

[0074] The interpolation value corresponding to grid (i,j) is also a predetermined correction value corresponding to grid (i,j). After the predetermined correction value is determined, the control device 21 can correct the distance determined by the distance measurement signal in NLOS transmission using the predetermined correction value so that an accurate distance can be obtained.

[0075] For example, one position measuring anchor adjacent to this one reference anchor is the first adjacent anchor. When the control device 21 determines this one reference anchor from among the multiple position measuring anchors based on the distance between each of the multiple position measuring anchors and the key 11, the control device 21 uses a method similar to that of S101 to S102 to calculate the position measurement for the distance between this one reference anchor and each of the first adjacent anchors and the key 11, and the distance between this one reference anchor and the first adjacent anchor, and obtains the first position information of the key 11 relative to the vehicle. The control device 21 determines the coordinate point (X) within the grid (i,j) i ,Y j ) condition β i1 ≤X i ≤β i2 and β j1 ≦Y j ≤β j2 Based on this, the grid identifier (i,j) corresponding to the first position information is determined. The control device 21 determines the interpolated value of the first adjacent anchor corresponding to the grid (i,j) according to the grid identifier (i,j). The interpolated value of the first adjacent anchor corresponding to the grid (i,j) is, in other words, a predetermined correction value corresponding to the first position information. The control device 21 uses the predetermined correction value corresponding to the first position information to recalculate the distance between the first adjacent anchor and the key, and obtains the corrected distance of the first adjacent anchor. For example, the control device 21 obtains the corrected distance of the first adjacent anchor by subtracting the interpolated value of the first adjacent anchor corresponding to the grid (i,j) from the distance between the first adjacent anchor and the key.

[0076] The control device 21 calculates positional measurements for the distance between each of the one reference anchor and the first adjacent anchor and the key 11, and for the distance between the one reference anchor and the first adjacent anchor, using a method similar to that of S101 to S102, and obtains first positional information of the key 11 relative to the vehicle. For example, the control device 21 sets the line connecting the one reference anchor and the first adjacent anchor as the X-axis, and sets either the one reference anchor or the first adjacent anchor as the coordinate origin to determine a first local coordinate system that corresponds to both the one reference anchor and the first adjacent anchor. Based on the distance between each of the one reference anchor and the first adjacent anchor and the key, and for the distance between the one reference anchor and the first adjacent anchor, the control device 21 determines the first local coordinates of the key 11 in the first local coordinate system according to the law of cosines, similar to the embodiment in Figure 5. The control device 21 performs a coordinate system transformation process on the first local coordinates using a method similar to that shown in step S102, obtains the first coordinates of the key 11 in a predetermined coordinate system of the vehicle, and these first coordinates become the first position information of the key 11 relative to the vehicle.

[0077] After the correction distance of the first adjacent anchor is determined according to step S202, the final position information of the key 11 relative to the vehicle can be determined by performing step S203 based on the correction distance of the first adjacent anchor.

[0078] In S203, the control device 21 calculates the position measurement based on the distance between this one reference anchor and the key 11 and the correction distance of the first adjacent anchor, and obtains the final position information of the key 11 relative to the vehicle.

[0079] For example, the control device 21 calculates position measurements using a method similar to that of S101-S102, with respect to the distance between this one reference anchor and the key 11, the correction distance of the first adjacent anchor, and the distance between this one reference anchor and the first adjacent anchor, and obtains the final position information of the key 11 relative to the vehicle.

[0080] Figure 9 is a schematic diagram of the relationship between the first and second regions and a predetermined region of the anchor provided in the embodiment of the present application. As shown in Figure 9, each anchor preset region includes two first regions (e.g., first region 1 and first region 2) and one second region.

[0081] The first region shows that the accuracy of the final position of key 11 is related to one position-measuring anchor adjacent to this one reference anchor corresponding to the anchor preset region.

[0082] The second region shows that the accuracy of the final position of key 11 is related to two position-measuring anchors adjacent to this one reference anchor corresponding to the anchor preset region. As shown in Figure 9, in the second region corresponding to UWB1, the corresponding one reference anchor is UWB1, and the position-measuring anchors adjacent to this one reference anchor UWB1 are UWB2 and UWB4, respectively. In the same second region, the second region corresponding to UWB1 in Figure 9, when key 11 is in this second region, the position information obtained by calculating the position measurement for key 11 based on UWB1 and UWB2, and the position information obtained by calculating the position measurement for key 11 based on UWB1 and UWB4, are on opposite sides of the central axis of the second region. Therefore, when key 11 is in this second region, the position information obtained by calculating the position measurement for key 11 based on this one reference anchor and one position measurement anchor adjacent to this reference anchor is repeatedly reversed on both sides of the central axis of the second region. From this, it is shown that the accuracy of the final position of key 11 in the second region is related to the two position measurement anchors adjacent to this one reference anchor that corresponds to the anchor preset region.

[0083] Optionally, the angle between the central axis of the second region and the Y-axis (or X-axis) of the car's predetermined coordinate system may be 45°.

[0084] Selectively, the width of the second region can be determined according to theoretical calculations and key measurement results within the anchor preset region, for example, let the width of the second region be W = 10σ. Here, σ is the variance of the distance measurement error of the position measuring device at the position measuring anchor, and if the position measuring device is a UWB device, the corresponding σ is 6-10 (centimeters), and if the distance measurement follows a normal distribution, the probability of being within 3σ is 0.9974.

[0085] If the first position information determined in step S202 is within a predetermined first area, the control device 21 calculates the position measurement using a method similar to that of S101 to S102, with respect to the distance between this one reference anchor and the key 11, the correction distance of the first adjacent anchor, and the distance between this one reference anchor and the first adjacent anchor, obtains the first position measurement result of the key 11, and determines the final position information of the key 11 relative to the vehicle as the first position measurement result.

[0086] For example, if the first position information is in a predetermined first region, the control device 21 determines a first local coordinate system by setting the line connecting the one reference anchor and the first adjacent anchor as the X-axis, and the one reference anchor or the first adjacent anchor as the coordinate origin. Based on the distance between the one reference anchor and the key, the correction distance of the first adjacent anchor, and the distance between the one reference anchor and the first adjacent anchor, the control device 21 determines the first local corrected coordinates of the key 11 in the first local coordinate system according to a calculation means of the law of cosines similar to that in the embodiment of Figure 5. The control device 21 performs a coordinate system transformation process on the first local corrected coordinates using a method similar to the method shown in step S102 to obtain the first corrected coordinates of the key 11 in the predetermined coordinate system of the vehicle. The control device 21 determines the first corrected coordinates as the final position information of the key 11 relative to the vehicle and increases the position measurement speed of the key 11.

[0087] The other position-measuring anchor adjacent to this one reference anchor is the second adjacent anchor.

[0088] If the first position information determined in step S202 is in a predetermined second area, the control device 21 calculates the position measurement using a method similar to that of S101 to S102, for the distance between the key and each of the one reference anchor and the second adjacent anchor, and for the distance between the one reference anchor and the second adjacent anchor, and obtains the second position information of the key 11 relative to the vehicle. The control device 21 recalculates the distance between the second adjacent anchor and the key using a predetermined correction value corresponding to the second position information, and obtains the corrected distance of the second adjacent anchor. The control device 21 calculates the position measurement using a method similar to that of S101 to S102, for the distance between the one reference anchor and the key 11, for the corrected distance of the second adjacent anchor, and for the distance between the one reference anchor and the second adjacent anchor, and obtains the second position measurement result of the key 11. The control device 21 determines the average value of the first position measurement result and the second position measurement result as the final position information of the key 11 relative to the vehicle, thereby improving the accuracy of the position measurement of the key 11 in the second region.

[0089] The control device 21 calculates the position measurement for the distance between the one reference anchor and the key 11, the correction distance of the second adjacent anchor, and the distance between the one reference anchor and the second adjacent anchor, using a method similar to that of S101 to S102, and obtains the second position measurement result of the key 11. For example, the control device 21 determines a second local coordinate system with the line connecting the one reference anchor and the second adjacent anchor as the X-axis, and the one reference anchor or the second adjacent anchor as the coordinate origin. Based on the distance between the one reference anchor and the key 11, the correction distance of the second adjacent anchor, and the distance between the one reference anchor and the second adjacent anchor, the control device 21 determines the second local corrected coordinate of the key 11 in the second local coordinate system according to a calculation means of the law of cosines similar to that of the embodiment in Figure 5. The control device 21 performs a coordinate system transformation process on the second local corrected coordinate using a method similar to that shown in step S102, and obtains the second corrected coordinate of the key 11 in the predetermined coordinate system of the vehicle.

[0090] For example, the first position measurement result includes the first corrected coordinates of the key 11 in a predetermined coordinate system of the vehicle. The second position measurement result includes the second corrected coordinates of the key 11 in a predetermined coordinate system of the vehicle. If the first position information is in a predetermined second region, the control device 21 calculates the average value of the coordinate values ​​for the first corrected coordinates and the second corrected coordinates to obtain the final coordinates of the key 11 in the predetermined coordinate system of the vehicle. The final coordinates of the key 11 in the predetermined coordinate system of the vehicle are, in other words, the final position information of the key 11 relative to the vehicle.

[0091] Within the same anchor preset region, if the first region lies on one side of the second region and an adjacent position measuring anchor, this indicates that the first region corresponds to this adjacent position measuring anchor. The adjacent position measuring anchor is the position measuring anchor adjacent to the position measuring anchor corresponding to the anchor preset region.

[0092] Selectively, if the control device 21 determines one reference anchor from among the multiple position measuring anchors based on the distance between each of the multiple position measuring anchors and the key 11, the control device 21 can acquire first position information corresponding to the first adjacent anchor of this one reference anchor and second position information corresponding to the second adjacent anchor of this one reference anchor. If the control device 21 determines that the first position information and the second position information are all in the same first region, the control device 21 measures the position of the key 11 based on the adjacent position measuring anchors corresponding to this first region and this one reference anchor. For example, the control device 21 uses a method similar to that of S101 to S102 to calculate the position measurement for the corrected distance corresponding to the adjacent position measuring anchors corresponding to this first region, the distance between this one reference anchor and the key 11, and the distance between this one reference anchor and the adjacent position measuring anchors corresponding to this first region, and acquires the final position information of the key 11 relative to the vehicle.

[0093] After the control device 21 obtains the final position information of the key 11 relative to the vehicle in accordance with step S203, the control device 21 performs step S204.

[0094] In S204, the control device 21 performs a predetermined operation that corresponds to both the final position information of the key 11 relative to the vehicle and the control command transmitted from the key 11.

[0095] The following is a diagram. 5 Using this as an example, we will illustrate the measurement of the car key's position shown in Figure 6 using the methods described in steps (1) to (4).

[0096] (1) Figure 5 As shown, after establishing a communication connection with key A of vehicle A, the control device 21 of vehicle A determines the distances between key A and each of the four position measuring devices UWB1, UWB2, UWB3, and UWB4 in vehicle A to be d1a, d2a, d3a, and d4a, respectively, based on distance measuring signals between key A and each of the four UWB1, UWB2, UWB3, and UWB4. A transmission mode of the distance measuring signal between key A and UWB1 being LOS indicates that the actual distance between key A and UWB1 is the same as or equivalent to d1a. A transmission mode of the distance measuring signals between key A and each of UWB2, UWB3, and UWB4 being NLOS indicates that the actual distance between key A and UWB2 is less than d2a, the actual distance between key A and UWB3 is less than d3a, and the actual distance between key A and UWB4 is less than d4a.

[0097] In the embodiments of this application, the actual distance between two points is the straight-line distance between them. Exemplarily, the actual distance between key A and UWB4 is, i.e., the straight-line distance between key A and UWB4.

[0098] (2) The control device 21 determines one reference anchor UWB1 based on the distance between each of the four position measuring anchors UWB1, UWB2, UWB3, and UWB4 and key A. Position measuring anchors adjacent to UWB1 include UWB2 and UWB4. If UWB2 is the first adjacent anchor, then UWB4 becomes the second adjacent anchor.

[0099] (3) The control device 21 calculates the position of the distance between UWB1 and key A, the distance between UWB2 and key A, and the distance between UWB1 and UWB2 using a method similar to that shown in steps S101 to S102, and obtains the first position information of key A. Then, the control device 21 calculates the position of the distance between UWB1 and key A, the distance between UWB4 and key A, and the distance between UWB1 and UWB4 using a method similar to that shown in steps S101 to S102, and obtains the second position information of key A.

[0100] (4) If the first and second location information are all in the same first region, steps (4.1.1) to (4.1.4) are executed. If the first and second location information are all in the same second region, steps (4.2.1) to (4.2.5) are executed.

[0101] (4.1.1) The first location information and the second location information are all in the same first region, and the same first region is shown in Figure 9 If the first region 1 corresponds to UWB1 shown and the first region 1 corresponds to UWB4, the control device 21 determines the grid identifier (i1, j1) corresponding to the second position information according to the second position information.

[0102] (4.1.2) The control device 21 uses the interpolated value Δd4(i1,j1) of the position measurement anchor UWB4 corresponding to the grid (i1,j1) to control the grid. In the equation d4ax=d4a-Δd4(i1,j1), Correct the distance d4a between UWB4 and key A, and obtain the corrected distance d4ax corresponding to UWB4.

[0103] (4.1.3) The control device 21 calculates the position measurement for d1a, d4ax and the distance between UWB1 and UWB4 using a method similar to the method shown in steps S101 to S102, and the second corrected coordinate (x gA2 ,y gA2 The control device 21 obtains (x gA2 ,y gA2 ) is determined as the final coordinates of key A relative to car A.

[0104] (4.1.4) The control device 21 receives the final position information of key A relative to vehicle A (for example (x gA2 ,y gA2 )) and execute a predetermined operation corresponding to both the control command sent from key A.

[0105] (4.2.1) The first and second location information are all in the same second region, and the same second region is shown in Figure 9 If it is a second region in the anchor preset region corresponding to UWB1 shown, the control device 21 determines the grid identifier (i1, j1) corresponding to the second position information according to the second position information, and determines the grid identifier (i2, j2) corresponding to the first position information according to the first position information.

[0106] (4.2.2) The control device 21 uses the interpolated value Δd4(i1,j1) of the position measurement anchor UWB4 corresponding to the grid (i1,j1) to control the grid. In the equation d4ax=d4a-Δd4(i1,j1), The control device 21 corrects the distance d4a between UWB4 and key A, obtains the corrected distance d4ax corresponding to UWB4, and then uses the interpolated value Δd2(i2,j2) of the position measurement anchor UWB2 corresponding to the grid (i2,j2) d2ax= d2a In the equation -Δd2(i2,j2), The distance d2a between UWB2 and key A is corrected, and the corrected distance d2ax corresponding to UWB2 is obtained.

[0107] (4.2.3) The control device 21 calculates the position measurement for d1a, d4ax and the distance between UWB1 and UWB4 using a method similar to the method shown in steps S101 to S102, and the second corrected coordinate (x gA2 ,y gA2 The control device 21 then uses a method similar to that shown in steps S101 to S102 to calculate the position measurement for d1a, d2ax and the distance between UWB1 and UWB2, and obtains the first corrected coordinate (x gA1 ,y gA1 ) obtain.

[0108] (4.2.4) The control device 21 is JPEG2026509759000023.jpg1758 and According to JPEG2026509759000024.jpg1758, the second corrected coordinate (x gA2 ,y gA2 ) and the first corrected coordinate (x gA1 ,y gA1 For ), calculate the average value and determine the final coordinates (x) of key A in the predetermined coordinate system of car A. gA ,y gA ) obtain.

[0109] (4.2.5) The control device 21 receives the final position information of key A relative to vehicle A (for example (x gA ,y gA )) and execute a predetermined operation corresponding to both the control command sent from key A.

[0110] The position measurement of key A shown in Figure 6 will be explained exemplified below, with reference to the position measurement process shown in Figure 10.

[0111] (a) After a communication connection is established between key A and vehicle A, position measurement of key A outside the vehicle body begins, and the system waits until vehicle A's control device 21 initiates the position measurement procedure.

[0112] (b) After the control device 21 initiates the position measurement procedure, the control device 21 of vehicle A acquires information on the four position measurement anchors in vehicle A, namely the status identifier (e.g., valid identifier), ToF, and RSSI.

[0113] (c) The control device 21 arranges the ToF of the four position measuring anchors in ascending order and acquires the anchor sequence.

[0114] (d) The control device 21 uses the first and second position measuring anchors in the anchor sequence to perform a dual anchor position measurement of key A in the same manner as the position measurement calculation method in steps S101 to S102, and obtains the coordinates (x1, y1) of key A in a predetermined coordinate system of vehicle A.

[0115] (e) The control device 21 determines whether the coordinate (x1, y1) is within the anchor preset region, and if the coordinate (x1, y1) is not within the anchor preset region, the control device 21 Step (e1) is executed, which outputs the coordinates (x1, y1) as the final position information (x, y) of key A. If the coordinates (x1, y1) are within the anchor preset region, the control device 21 executes the following steps (e2)-(e4).

[0116] (e2) The control device 21 corrects the distance between the second position measuring anchor and key A in the anchor sequence and obtains the corrected distance.

[0117] (e3) The control device 21 measures the dual anchor position of key A according to the same means as the position measurement calculation means in steps S101 to S102, based on the distance between the first position measuring anchor and key A and the correction distance corresponding to the second position measuring anchor, and obtains the coordinates (x2, y2) of key A in a predetermined coordinate system of vehicle A.

[0118] (e4) The control device 21 determines whether the coordinate (x1, y1) is in the second region, and if the coordinate (x1, y1) is not in the second region, the control device 21 The control device 21 performs step (e41) which outputs the coordinates (x2, y2) as the final position information (x, y) of key A, If the coordinates (x1, y1) are in the second region, the control device 21 executes steps (e42) to (e45).

[0119] (e42) The control device 21 corrects the distance between the third position measuring anchor and key A in the anchor sequence and obtains the corrected distance.

[0120] (e43) Based on the distance between the first position measuring anchor and key A and the correction distance corresponding to the third position measuring anchor, the control device 21 performs a dual anchor position measurement of key A in accordance with the same means as the position measurement calculation means in steps S101 to S102, and obtains the coordinates (x3, y3) of key A in a predetermined coordinate system of vehicle A.

[0121] (e44) The control device 21 calculates the final position information (x,y) of key A relative to vehicle A according to x=(x2+x3) / 2 and y=(y2+y3) / 2.

[0122] (e45) The control device 21 outputs the final position information (x,y) of key A.

[0123] The car key position measurement method provided in this embodiment determines a reference anchor in LOS transmission from among multiple position measurement anchors, and if there is one reference anchor, performs position measurement calculations using the distance between the reference anchor and the key in LOS transmission and the corrected distance between adjacent position measurement anchors and the key in NLOS transmission to obtain accurate final position information of the key relative to the car and improve the accuracy of key position measurement. Furthermore, if the key is in the first region of the anchor preset area, position measurement is performed using the reference anchor and one position measurement anchor adjacent to the reference anchor to increase the key position measurement speed, and if the key is in the second region of the anchor preset area, the average value of the corrected coordinates corresponding to two position measurement anchors adjacent to the reference anchor is calculated to obtain accurate final position information of the key relative to the car and improve the accuracy of key position measurement in the second region. The car key positioning method provided in the embodiment of this application reduces, and preferably eliminates, the adverse effects of inaccurate distance information determined by distance measurement signals in NLOS transmission on the accuracy of key positioning, thereby improving key positioning accuracy and solving the problem of inaccurate positioning in conventional key positioning methods. The car key positioning method provided in the embodiment of this application enables accurate positioning of the key at different orientations of the car by deploying only four positioning anchors, saving resources for positioning devices at the positioning anchors.

[0124] The embodiments of the present application further provide a control device, and Figure 11 is a structural diagram 1 of the control device provided in the embodiments of the present application. As shown in Figure 11, the control device comprises a collection module 41, a processing module 42, and an operation module 43. The collection module 41 is used to determine the distance between each of the multiple position-measuring anchors in the vehicle and the key, based on distance-measuring signals between each of the multiple position-measuring anchors in the vehicle and the key, after a communication connection between the vehicle and the vehicle key has been established. The processing module 42 is used to obtain the corrected distance when a reference anchor is determined from among the multiple position measuring anchors based on the distance between each of the multiple position measuring anchors and the key, and when a reference anchor is determined from among the multiple position measuring anchors. The reference anchor indicates that the transmission mode of the distance measuring signal to the key is line-of-sight radio transmission (LOS). The processing module 42 performs position measurement calculations for the distance and correction distance between one reference anchor and the key, and is further used to obtain the final position information of the key relative to the vehicle. The operation module 43 is used to perform predetermined operations that correspond to both the final position information of the key relative to the vehicle and the control commands transmitted from the key.

[0125] Optionally, the collection module 41 further comprises a Bluetooth® (BLE) module 411. The Bluetooth® module 411 is used to broadcast BLE broadcast signals and is also used for Bluetooth® distance measurement of the key.

[0126] Since the specific implementation principle and technical effects of the control device provided in the embodiment of this application are similar to those of the embodiment shown in Figure 7, the explanation of this embodiment will be omitted here.

[0127] Embodiments of the present application further provide a control device. Figure 12 is a structural diagram 2 of the control device provided in an embodiment of the present application. As shown in Figure 12, the control device comprises a processor 51 and a memory 52, the memory 52 storing instructions executable by the processor 51 so that the processor 51 can be used to perform the technical solution according to the embodiment of the method described above, and since the implementation principles and technical effects are similar, this embodiment will not be described here. It should be understood that the processor 51 may be a central processing unit (CPU), or it may be another general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), etc. The general-purpose processor may be a microprocessor, or it may be any conventional processor, etc. The steps of the method disclosed in connection with the invention may be directly embodied as being executed and completed by a hardware processor, or by a combination of hardware and software modules in a processor. Memory 52 may be equipped with high-speed random access memory (RAM), and may further be equipped with non-volatile memory (NVM), for example, at least one magnetic disk memory, and other examples include USB flash drives, removable hard drives, read-only memory, magnetic disks, or compact disks.

[0128] Embodiments of the present invention further provide a storage medium on which computer execution instructions are stored, and when these computer execution instructions are executed by a processor, the above-described method for determining the position of a car key is realized. The storage medium can be implemented by any type of volatile or non-volatile storage device, or a combination thereof, such as static random-access memory (SRAM), electrically-erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or compact disk. The storage medium may be any available medium accessible by a general-purpose or special-purpose computer.

[0129] The storage medium is coupled to the processor, for example, so that the processor can read information from and write information to the storage medium. Naturally, the storage medium may also be a component of the processor. The processor and storage medium may be located within an Application Specific Integrated Circuit (ASIC). Naturally, the processor and storage medium may also exist as separate components within an electronic device or master device.

[0130] The embodiment of the present invention further provides a program product such as a computer program, and when the computer program is executed by a processor, the method for measuring the position of a car key according to the present invention is realized.

[0131] Those skilled in the art will understand that all or part of the steps for implementing the embodiments of each of the above methods may be performed by hardware associated with program instructions. The program may be stored in a storage medium readable by a computer. When this program is executed, the steps including the embodiments of each of the above methods are performed. The aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or compact disks.

[0132] Finally, it should be noted that the embodiments described above are used solely to illustrate the technical solutions of the present invention and are not limiting. While the present invention has been described in detail with reference to the embodiments described above, those skilled in the art can still modify the technical solutions described in the embodiments above or make equivalent substitutions to some or all of their technical features, and these modifications or substitutions should be understood not to deviate from the essence of the corresponding technical solutions within the scope of the technical solutions of the embodiments of the present invention.

[0133] <Cross-reference of related applications> This application claims priority to a Chinese patent application filed with the China National Intellectual Property Administration on June 16, 2023, with application number 202310725924.7, titled "Method, apparatus, and storage medium for measuring the position of a car key," the entirety of which is incorporated into this application by reference.

Claims

1. After a communication connection is established between the vehicle and the vehicle's key, the distance between each of the multiple position-measuring anchors in the vehicle and the key is determined based on the distance-measuring signal between each of the multiple position-measuring anchors and the key. Based on the distance between each of the plurality of position measuring anchors and the key, if one reference anchor is determined from among the plurality of position measuring anchors, the distance between the position measuring anchor adjacent to the one reference anchor and the key is corrected, and the corrected distance is obtained. The steps include: calculating the position measurement based on the distance between the one reference anchor and the key and the corrected distance, and obtaining the final position information of the key relative to the vehicle; The step includes performing a predetermined operation that corresponds to both the final position information of the key for the vehicle and the control command transmitted from the key, A method for measuring the position of a car key, characterized in that the reference anchor indicates that the transmission mode of the distance measurement signal between it and the key is line-of-sight wireless transmission (LOS).

2. One of the position-measuring anchors adjacent to the aforementioned reference anchor is the first adjacent anchor. The step of correcting the distance between the position measuring anchor adjacent to the one reference anchor and the key, and obtaining the corrected distance, The steps include: calculating the position measurement based on the distance between each of the one reference anchor and the first adjacent anchor and the key, and the distance between the one reference anchor and the first adjacent anchor, and obtaining first position information of the key relative to the vehicle; The method according to claim 1, comprising the step of correcting the distance between the first adjacent anchor and the key using a predetermined correction value corresponding to the first position information, and obtaining the corrected distance of the first adjacent anchor.

3. The step of calculating a position measurement based on the distance between the one reference anchor and the key and the correction distance, and obtaining the final position information of the key relative to the vehicle, is: If the first position information is within a predetermined first area, the step of calculating a position measurement with respect to the distance between one reference anchor and the key, the correction distance of the first adjacent anchor, and the distance between one reference anchor and the first adjacent anchor, and obtaining the first position measurement result of the key, The step includes determining the first position measurement result as the final position information of the key relative to the vehicle, The method according to 2, characterized in that the first region indicates that the accuracy of the final position of the key is related to a position measuring anchor adjacent to the one reference anchor.

4. The other position-measuring anchor adjacent to the aforementioned reference anchor is a second adjacent anchor. The step of calculating a position measurement based on the distance between the one reference anchor and the key and the correction distance, and obtaining the final position information of the key relative to the vehicle, is: If the first position information is in a predetermined second area, the step of calculating a position measurement with respect to the distance between each of the one reference anchor and the second adjacent anchor and the key, and the distance between the one reference anchor and the second adjacent anchor, and obtaining the second position information of the key relative to the vehicle, The steps include: calculating the correct distance between the second adjacent anchor and the key using a predetermined correction value corresponding to the second position information, and obtaining the corrected distance of the second adjacent anchor; The steps include: performing position measurement calculations with respect to the distance between the one reference anchor and the key, the correction distance of the second adjacent anchor, and the distance between the one reference anchor and the second adjacent anchor, and obtaining the second position measurement result of the key; The step includes determining the average value of the first position measurement result and the second position measurement result as the final position information of the key relative to the vehicle, The method according to 3, characterized in that the second region indicates that the accuracy of the final position of the key is related to two adjacent position measuring anchors of the one reference anchor.

5. The step of calculating a position measurement based on the distance between each of the one reference anchor and the first adjacent anchor and the key, and the distance between the one reference anchor and the first adjacent anchor, and obtaining the first position information of the key relative to the vehicle, is: The first step is to determine a first local coordinate system, with the line connecting the one reference anchor and the first adjacent anchor being the X-axis, and the one reference anchor or the first adjacent anchor being the coordinate origin. A step of determining the first local coordinates of the key in the first local coordinate system based on the distance between each of the one reference anchor and the first adjacent anchor and the key, and the distance between the one reference anchor and the first adjacent anchor. The process includes the step of performing a coordinate system transformation on the first local coordinates to obtain the first coordinates of the key in a predetermined coordinate system of the vehicle, The method according to any one of claims 2 to 4, characterized in that the first coordinate is the first position information of the key with respect to the vehicle.

6. The step of calculating a position measurement with respect to the distance between the one reference anchor and the key, the correction distance of the first adjacent anchor, and the distance between the one reference anchor and the first adjacent anchor, and obtaining a first position measurement result of the key, is: The first step is to determine a first local coordinate system, with the line connecting the one reference anchor and the first adjacent anchor being the X-axis, and the one reference anchor or the first adjacent anchor being the coordinate origin. A step of determining the first local modified coordinates of the key in the first local coordinate system based on the distance between the one reference anchor and the key, the modification distance of the first adjacent anchor, and the distance between the one reference anchor and the first adjacent anchor. The process includes the step of performing a coordinate system transformation on the first local modified coordinates to obtain the first modified coordinates of the key in a predetermined coordinate system of the vehicle, The step of calculating a position measurement with respect to the distance between the one reference anchor and the key, the correction distance of the second adjacent anchor, and the distance between the one reference anchor and the second adjacent anchor, and obtaining a second position measurement result for the key, is as follows: The steps include determining a second local coordinate system by defining the line connecting the first reference anchor and the second adjacent anchor as the X-axis, and using the first reference anchor or the second adjacent anchor as the coordinate origin, A step of determining the second local modified coordinates of the key in the second local coordinate system based on the distance between the one reference anchor and the key, the modified distance of the second adjacent anchor, and the distance between the one reference anchor and the second adjacent anchor, The method according to claim 4, further comprising the step of performing a coordinate system transformation process on the second local corrected coordinates to obtain the second corrected coordinates of the key in a predetermined coordinate system of the vehicle.

7. The step of determining the average value of the first position measurement result and the second position measurement result as the final position information of the key relative to the vehicle is as follows: The method according to 6, further comprising the step of calculating an average value for the first corrected coordinate and the second corrected coordinate, and obtaining the final coordinate of the key in a predetermined coordinate system of the vehicle.

8. A control device comprising a collection module, a processing module, and an operation module, The collection module is used to determine the distance between each of the multiple position-measuring anchors in the vehicle and the key, based on distance-measuring signals between each of the multiple position-measuring anchors in the vehicle and the key, after a communication connection has been established between the vehicle and the vehicle key. The processing module, based on the distance between each of the plurality of position measuring anchors and the key, determines one reference anchor from among the plurality of position measuring anchors, and is used to correct the distance between the position measuring anchor adjacent to the one reference anchor and the key, and to obtain the corrected distance. The processing module is further used to calculate position measurements based on the distance between the one reference anchor and the key and the corrected distance, and to obtain the final position information of the key relative to the vehicle. The operation module is used to perform a predetermined operation that corresponds to both the final position information of the key relative to the vehicle and the control command transmitted from the key. The control device is characterized in that the reference anchor indicates that the transmission mode of the distance measurement signal between it and the key is line-of-sight wireless transmission (LOS).

9. A control device comprising a processor and memory, The memory stores executable instructions that can be executed by the processor. A control device characterized in that, when the processor executes an executable instruction stored in the memory, the processor performs the method according to any one of claims 1 to 7.

10. A storage medium in which computer execution instructions are stored, wherein the computer execution instructions are used to implement the method described in any one of claims 1 to 7 when executed by a processor.

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