Ultra-wideband positioning method, device and storage medium based on multi-anchor point collaboration

Abstract

This application discloses an ultra-wideband positioning method, device, and storage medium based on multi-anchor point collaboration, relating to the field of wireless communication network technology. The method includes: locating a user tag based on a first primary positioning anchor point and a second primary positioning anchor point to obtain the user tag's first planar coordinates; determining a first verification anchor point from the same horizontal plane of the first and second primary positioning anchor points; determining a third measured distance between the first verification anchor point and the user tag, and a theoretical distance between the first planar coordinates and the first verification anchor point; when the absolute value of the difference between the theoretical distance and the third measured distance is determined as a residual, if the residual is less than a preset difference threshold, confirming the first planar coordinates as the second planar coordinates; this method can improve the accuracy of ultra-wideband positioning in subway gate scenarios.

Description

Technical Field

[0001] This application relates to the field of wireless communication network technology, and in particular to an ultra-wideband positioning method, device and storage medium based on multi-anchor point cooperation. Background Technology

[0002] In current UWB positioning solutions for seamless gate access, when the anchor point experiences ranging errors due to non-line-of-sight obstruction, multipath reflection, or environmental interference, these errors do not trigger hardware error codes, and the system receives the erroneous ranging values ​​as valid data. For example, when a user's body, luggage, or other obstacles block the straight-line propagation path between the anchor point and the tag, the signal will diffract or reflect, causing the ranging value to be larger than the actual distance. Incorrect ranging values ​​pose safety risks such as injury to people or unauthorized entry, or they may obstruct users, affecting their passage experience.

[0003] The above content is only used to help understand the technical solution of this application and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The main purpose of this application is to provide an ultra-wideband positioning method based on multi-anchor point collaboration, which aims to solve the technical problem of how to improve the accuracy of ultra-wideband positioning in subway gate scenarios.

[0005] To address the aforementioned problems, this application provides an ultra-wideband positioning method based on multi-anchor point cooperation, which includes:

[0006] The user tag is located based on the first and second primary positioning anchor points to obtain the first planar coordinates of the user tag.

[0007] The first verification anchor point is determined from the same horizontal plane of the first main positioning anchor point and the second main positioning anchor point;

[0008] Determine the third measured distance between the first verification anchor point and the user tag, and the theoretical distance between the first planar coordinates and the first verification anchor point;

[0009] When the absolute value of the difference between the theoretical distance and the third measured distance is determined as the residual, if the residual is less than a preset difference threshold, the first plane coordinates are confirmed as the second plane coordinates.

[0010] In one embodiment, before the step of locating the user tag based on the first primary positioning anchor point and the second primary positioning anchor point to obtain the first planar coordinates of the user tag, the ultra-wideband positioning method based on multi-anchor point collaboration further includes:

[0011] Based on the user tag, ranging signals are sent to the first verification anchor point, the first primary positioning anchor point, and the second primary positioning anchor point respectively to obtain the third measured distance, the first measured distance between the first primary positioning anchor point and the user tag, and the second measured distance between the second primary positioning anchor point and the user tag.

[0012] In one embodiment, the step of locating the user tag based on the first primary positioning anchor point and the second primary positioning anchor point to obtain the first planar coordinates of the user tag includes:

[0013] Two circles are generated, one with the first main positioning anchor point as the center and the other with the first measured distance as the radius, and the other with the second main positioning anchor point as the center and the other with the second measured distance as the radius.

[0014] The coordinates of the intersection point of the two circles are determined as the potential plane coordinates;

[0015] The coordinates in the potential plane coordinates where the vertical coordinate is positive and the horizontal coordinate is within the preset channel width range are determined as the first plane coordinates.

[0016] In one embodiment, before the step of locating the user tag based on the first primary positioning anchor point and the second primary positioning anchor point to obtain the first planar coordinates of the user tag, the ultra-wideband positioning method based on multi-anchor point cooperation further includes:

[0017] Determine the RSSI value, ranging success rate, and historical verification residual for each preset anchor point;

[0018] The signal quality score is obtained by weighted summing of the RSSI value, the ranging success rate and the historical verification residual.

[0019] The two preset anchor points with RSSI values ​​greater than a preset RSSI threshold and the highest signal quality scores are determined as the first primary positioning anchor point and the second primary positioning anchor point.

[0020] In one embodiment, after the step of confirming the first plane coordinates as the second plane coordinates, the ultra-wideband positioning method based on multi-anchor point cooperation further includes:

[0021] From the vertical plane of the first primary positioning anchor point or the second primary positioning anchor point, determine the second verification anchor point, and determine the primary positioning anchor point in the same vertical plane as the second verification anchor point as the target primary positioning anchor point;

[0022] The distance between the second verification anchor point and the target main positioning anchor point is determined as the vertical baseline length, the distance between the user tag and the second verification anchor point is determined as the fourth measured distance, and the distance between the user tag and the main positioning anchor point is determined as the fifth measured distance.

[0023] The original height of the user tag is determined based on the vertical baseline length, the fourth measured distance, and the fifth measured distance.

[0024] The height difference between the original height and the height constraint value is compared with a preset height difference threshold.

[0025] If the height difference is less than the height difference threshold, then the original height is determined as the effective height;

[0026] Based on the effective height and the second plane coordinates, the target three-dimensional coordinates of the user tag are obtained.

[0027] In one embodiment, after the step of comparing the height difference between the original height and the height constraint value with a preset height difference threshold, the ultra-wideband positioning method based on multi-anchor point collaboration may further include:

[0028] If the height difference is greater than or equal to the height difference threshold, then the height constraint value is determined as the effective height, and the formula for calculating the height constraint value is:

[0029] ,

[0030] in, Z is the height constraint value. B Let d be the height coordinate of the main positioning anchor point. B This is the fifth measured distance. The horizontal distance between the first planar coordinates and the main positioning anchor point.

[0031] In one embodiment, the step of obtaining the target three-dimensional coordinates of the user tag based on the effective height and the second planar coordinates includes:

[0032] Based on the effective height, determine the horizontal projected distance between the distance measurement values ​​of the first main positioning anchor point and the second main positioning anchor point;

[0033] Based on the double-circle intersection algorithm and the horizontal projection distance, the coordinates of the third plane, as well as the first ordinate and the first abscissa in the third plane coordinates, are determined;

[0034] The second ordinate is obtained by taking the square root of the difference between the first ordinate and the square of the effective height.

[0035] The target's three-dimensional coordinates are obtained by combining the first horizontal coordinate, the second vertical coordinate, and the effective height.

[0036] In one embodiment, after the step of obtaining the target three-dimensional coordinates of the user tag based on the effective height and the second planar coordinates, the ultra-wideband positioning method based on multi-anchor point collaboration further includes:

[0037] The target's three-dimensional coordinates are smoothed based on a preset number of frames to obtain the coordinate trajectory of the user tag;

[0038] The coordinate trajectory is compared with the preset valid passage area. If a preset number of consecutive frames are all within the valid passage area, identity and payment authorization verification is triggered.

[0039] If the verification is successful, the gate will be opened.

[0040] Furthermore, to achieve the above objectives, this application also proposes an ultra-wideband positioning method device based on multi-anchor point cooperation, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the ultra-wideband positioning method based on multi-anchor point cooperation as described above.

[0041] In addition, to achieve the above objectives, this application also proposes a storage medium, which is a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the steps of the ultra-wideband positioning method based on multi-anchor point cooperation as described above.

[0042] This application provides an ultra-wideband positioning method based on multi-anchor point collaboration. Preliminary planar coordinates are obtained by the intersection of two main positioning anchor points' double circles. Then, a verification anchor point on the same horizontal plane is introduced. The residual between the theoretical distance and the measured distance is compared to filter out erroneous coordinates caused by ranging noise and non-line-of-sight occlusion, thus avoiding biased data. Since the verification anchor point and the main positioning anchor point are on the same horizontal plane, the interference of height difference on distance calculation is eliminated, making the residual judgment more accurate. This method is suitable for scenarios with strong planar positioning requirements, such as turnstiles, reducing misjudgments and improving positioning accuracy. Attached Figure Description

[0043] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0044] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 This is a schematic diagram of the first process for the ultra-wideband positioning method based on multi-anchor point collaboration in this application;

[0046] Figure 2 A schematic diagram of anchor point deployment provided for the ultra-wideband positioning method based on multi-anchor point collaboration in this application;

[0047] Figure 3 This is a second flowchart illustrating the ultra-wideband positioning method based on multi-anchor point collaboration provided in this application.

[0048] Figure 4 This is a schematic diagram of the hardware operating environment involved in the ultra-wideband positioning method based on multi-anchor point collaboration in the embodiments of this application.

[0049] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0050] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0051] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0052] To achieve the above objectives, this application proposes an ultra-wideband positioning method based on multi-anchor point collaboration. The method includes: locating a user tag based on a first primary positioning anchor point and a second primary positioning anchor point to obtain the user tag's first planar coordinates; determining a first verification anchor point from the same horizontal plane of the first primary positioning anchor point and the second primary positioning anchor point; determining a third measured distance between the first verification anchor point and the user tag, and a theoretical distance between the first planar coordinates and the first verification anchor point; when the absolute value of the difference between the theoretical distance and the third measured distance is determined as a residual, if the residual is less than a preset difference threshold, confirming the first planar coordinates as the second planar coordinates.

[0053] In current UWB positioning solutions for seamless gate access, when the anchor point experiences ranging errors due to non-line-of-sight obstruction, multipath reflection, or environmental interference, these errors do not trigger hardware error codes, and the system receives the erroneous ranging values ​​as valid data. For example, when a user's body, luggage, or other obstacles block the straight-line propagation path between the anchor point and the tag, the signal will diffract or reflect, causing the ranging value to be larger than the actual distance. Incorrect ranging values ​​pose safety risks such as injury to people or unauthorized entry, or they may obstruct users, affecting their passage experience.

[0054] This application provides an ultra-wideband positioning method based on multi-anchor point collaboration. Preliminary planar coordinates are obtained by the intersection of two main positioning anchor points' double circles. Then, a verification anchor point on the same horizontal plane is introduced. The residual between the theoretical distance and the measured distance is compared to filter out erroneous coordinates caused by ranging noise and non-line-of-sight occlusion, thus avoiding biased data. Since the verification anchor point and the main positioning anchor point are on the same horizontal plane, the interference of height difference on distance calculation is eliminated, making the residual judgment more accurate. This method is suitable for scenarios with strong planar positioning requirements, such as turnstiles, reducing misjudgments and improving positioning accuracy.

[0055] It should be noted that the executing entity in this embodiment can be a computing service device with network communication and program execution functions, such as a tablet computer, personal computer, or mobile phone, or an electronic device or apparatus capable of performing the above functions. The following description uses a device based on a multi-anchor point collaborative ultra-wideband positioning method as an example to illustrate this embodiment and the subsequent embodiments.

[0056] Based on this, embodiments of this application provide an ultra-wideband positioning method based on multi-anchor point collaboration, referring to... Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the ultra-wideband positioning method based on multi-anchor point collaboration in this application.

[0057] In this embodiment, the ultra-wideband positioning method based on multi-anchor point cooperation includes steps S10~S40:

[0058] Step S10: Locate the user tag based on the first primary positioning anchor point and the second primary positioning anchor point to obtain the first planar coordinates of the user tag.

[0059] In this embodiment, the first and second primary positioning anchor points are deployed on the same horizontal plane, serving as a positioning base station pair. They are responsible for providing basic two-dimensional planar ranging data and calculating the user tag coordinates (x, y). The measured distances from the user tag to the two anchor points are obtained through wireless ranging (such as UWB or Bluetooth AoA), while the anchor point coordinates and channel boundaries are read from the configuration file. Based on the measured distances from the user tag to the two anchor points, and combined with a two-circle intersection algorithm, two potential coordinate points of the tag are calculated, ignoring the one located on the back of the gate, to obtain the first planar coordinates of the user tag.

[0060] Before step S10, steps S01~S02 are also included:

[0061] Step S01: Based on the user tag, send ranging signals to the first verification anchor point, the first main positioning anchor point, and the second main positioning anchor point respectively to obtain the third measured distance, the first measured distance between the first main positioning anchor point and the user tag, and the second measured distance between the second main positioning anchor point and the user tag.

[0062] In this embodiment, when the main positioning process is initiated, ranging communication between the anchor points and the user tag is triggered synchronously. The user tag sends ranging signals, such as UWB (Ultra-Wideband) pulses or Bluetooth signals, to all anchor points. After receiving the signal, the anchor points obtain the measured distance value with the user tag by calculating the signal time-of-flight (ToF) or signal strength (RSSI).

[0063] Optionally, the user tag's location is achieved by measuring the Time-of-Flight (ToF) of the challenge response data packet, converting the distance, and combining this with multi-anchor positioning. Multiple anchor points with known locations and coordinates are deployed. The tag being located (e.g., a mobile phone, smartwatch) establishes communication connections with all anchor points. Through the clock synchronization mechanism of the UWB protocol, the local clocks of the anchor points and the tag maintain a deviation within microseconds. During the challenge phase, the user tag sends a challenge data packet to the anchor point at time T1 and records the timestamp of T1 locally. During the reception phase, the anchor point receives the challenge packet at time T2 and records T2; simultaneously, it immediately sends a response data packet to the user tag at time T3 and records T3. During the response reception phase, the user tag receives the response packet at time T4 and records T4. First, the total time for bidirectional interaction is calculated: T_total = T4 - T1, which includes the Time-of-Flight (ToF) of the data packet from the tag to the anchor point, the Time-of-Flight (ToF) of the data packet from the anchor point to the tag, and the processing delay of the anchor point, T_delay. Since the anchor point sends a response packet immediately after receiving the challenge packet, T_delay = T3 - T2 is a fixed hardware processing time that can be obtained in advance through calibration. The actual Time of Flight (ToF) is (T_total - T_delay) / 2. According to the formula Distance = Speed ​​× Time, the distance d between the tag and the anchor point is d = ToF × c, where c is the speed of light. This gives us the measured distance d between the user tag and a single anchor point.

[0064] Specifically, step S10 includes steps S11 to S13:

[0065] Step S11: Generate two circles with the first main positioning anchor point as the center and the first measured distance as the radius, and with the second main positioning anchor point as the center and the second measured distance as the radius.

[0066] Step S12: Determine the coordinates of the intersection point of the two circles as potential planar coordinates;

[0067] In this embodiment, please refer to Figure 2 , Figure 2 This is a schematic diagram of anchor point settings, with the first primary positioning anchor point Anchor A as the center and the first measured distance d as the boundary. A Draw a circle with radius d; using the second primary positioning anchor point Anchor B as the center and the second measured distance d as the radius. B Draw circles with radius , and the equations of the two circles are respectively.

[0068] , ;

[0069] By simultaneously solving the equations of the two circles and eliminating one variable through elimination, a linear equation is obtained, which represents the line containing the common chord of the two circles. Substituting this linear equation into the equation of any one of the circles yields at most two potential planar coordinates P1(x1, y1) and P2(x2, y2). When the two circles intersect, there are two distinct common points, corresponding to the two potential planar coordinates of the tag. Subsequently, physical constraints of the gate channel are used, such as the x-coordinate being within the channel width and the y-coordinate being positive, to select the unique and valid coordinates from these two points. When the two circles are tangent, they have only one intersection point. In this case, a ranging anomaly is identified, possibly due to tag obstruction or a ranging module malfunction, triggering a re-ranging or anchor point group switching process. If the two circles are separate or contained within each other, with no common point, coordinates cannot be calculated, and positioning is deemed a failure.

[0070] Step S13: The coordinates in the potential plane coordinates where the vertical coordinate is positive and the horizontal coordinate is within the preset channel width range are determined as the first plane coordinates.

[0071] In this embodiment, a unique and reasonable physical coordinate is selected based on the actual physical constraints of the gate channel.

[0072] Optionally, obtain the physical constraint parameters of the turnstile channel, with the X-axis constraint being the channel width range [X...]. min X max ], usually X min =0 (left boundary of the channel), X max The x-coordinate represents the actual width of the passage. Only if the x-coordinate falls within this range is the tag positioned within the passage. The y-axis constraint defines the passage direction range, where Y > 0 (the location of the gate panel). A positive y-value indicates the tag is in the waiting area outside the gate or in the already passed area inside; a negative y-value indicates it is behind the gate panel, belonging to an invalid area. For two potential coordinates, the x-axis range is checked to see if it satisfies the x-axis constraint, and the y-axis sign is checked. If only one coordinate satisfies all constraints, that coordinate is directly used as the first plane coordinate; if neither coordinate satisfies the constraints, the positioning is deemed invalid, triggering a re-measurement.

[0073] If both coordinates satisfy the constraints, an auxiliary filtering rule is triggered. This auxiliary filtering rule can be based on the continuity of historical trajectories, where the label position moves continuously without sudden jumps. Record the valid coordinates of the previous frame, calculate the distances between the two potential coordinates and the historical coordinates, and select the closer one as the first plane coordinate. Alternatively, the auxiliary filtering rule can be based on a predictive filtering of the passage direction. Whether the gate passage is one-way or two-way, passage direction rules can be preset to filter coordinates that do not conform to the direction. Preset the passage direction, for example, only allowing passage from the outside to the inside, defining an increasing Y-axis as the passage direction; compare the Y values ​​of the two potential coordinates, selecting the coordinate with the larger Y value, i.e., closer to the inside of the gate, as the first plane coordinate; if it is two-way passage, the movement direction of the historical trajectory is considered.

[0074] Step S20: Determine the first verification anchor point from the same horizontal plane of the first main positioning anchor point and the second main positioning anchor point.

[0075] In this embodiment, the first primary positioning anchor point, the second primary positioning anchor point, and the first verification anchor point are deployed on the same horizontal plane. The first and second primary positioning anchor points serve as a positioning base station pair, responsible for providing basic two-dimensional planar ranging data and calculating the user tag coordinates (x, y). The accuracy of these coordinates is mainly affected by the ranging errors of points A and B. The first verification anchor point is used as a collaborative verification base station, and its spatial geometric relationship with points A and B is used to perform secondary confirmation of the calculated position and filter out abnormal solutions.

[0076] Step S30: Determine the third measured distance between the first verification anchor point and the user tag, and the theoretical distance between the first plane coordinates and the first verification anchor point.

[0077] Step S40: When the absolute value of the difference between the theoretical distance and the third measured distance is determined as the residual, if the residual is less than a preset difference threshold, the first plane coordinates are confirmed as the second plane coordinates.

[0078] In this embodiment, based on the selected planar coordinates, the theoretical distance from the label to the verification anchor point is calculated in reverse. By comparing the residual between the theoretical value and the measured value, erroneous coordinates caused by distance measurement noise and occlusion are filtered out.

[0079] Based on the first plane coordinates P1(x, y) and the known coordinates (x, y) of the first verification anchor point C. C y CThe theoretical distance from the tag to the first verification anchor point C is calculated using the distance formula between two points. The process of calculating the theoretical distance involves reconstructing the straight-line distance from the user tag to the first verification anchor point C in the plane. Since the coordinates of the first plane are already determined to be reasonable coordinates, this theoretical distance is the ideal ranging value under error-free conditions. This value is only related to the coordinate position and is not affected by hardware ranging noise.

[0080] The formula for calculating the theoretical distance is: .

[0081] Using theoretical distance Subtract the third measured distance and take the absolute value of the difference as the residual Δd. Then, compare the calculated residual Δd with a preset threshold. For comparison, the residual threshold is preset. This can be achieved by placing tags at different locations within the turnstile channel, recording the residual between the theoretical and measured distances at each location, and then using the maximum A-value of multiple residuals and the sum of redundancies as the threshold. If... If the error between the measured distance and the theoretical distance is within the allowable range, it indicates that the first plane coordinates are true and reliable, the positioning is deemed valid, and the first plane coordinates are directly output as the final plane coordinates; if If the measured distance and the theoretical distance have an excessively large error, it indicates that the coordinates of the first plane may be incorrect coordinates caused by ranging noise or occlusion. Therefore, the positioning is deemed invalid, and the coordinates of the first plane are filtered out.

[0082] In this embodiment, preliminary planar coordinates are obtained by the intersection of the double circles of two main positioning anchor points. Then, a verification anchor point on the same horizontal plane is introduced. The residual between the theoretical distance and the measured distance is compared to filter out erroneous coordinates caused by ranging noise and non-line-of-sight occlusion, thus avoiding biased data. Since the verification anchor point and the main positioning anchor point are on the same horizontal plane, the interference of height difference on distance calculation is eliminated, making the residual judgment more accurate. This approach is suitable for scenarios with strong planar positioning requirements, such as turnstiles, reducing misjudgments and improving positioning accuracy.

[0083] Based on the first embodiment of this application, in the second embodiment of this application, the content that is the same as or similar to that in the first embodiment described above can be referred to the above description and will not be repeated hereafter. Furthermore, before step S10, steps A10 to A30 may also be included:

[0084] Step A10: Determine the RSSI value, ranging success rate, and historical verification residual for each preset anchor point.

[0085] Step A20: The RSSI value, the ranging success rate, and the historical verification residual are weighted and summed to obtain the signal quality score.

[0086] Step A30: The two preset anchor points with RSSI values ​​greater than a preset RSSI threshold and the highest signal quality scores are determined as the first primary positioning anchor point and the second primary positioning anchor point.

[0087] In this embodiment, the anchor point group is dynamically scheduled based on signal quality and verification results. The two anchor points with the best current signal are selected for primary positioning, and a third anchor point is used for verification, thereby effectively dealing with interference scenarios such as unilateral occlusion and nLOS (non-line-of-sight). For example, Anchor B and Anchor C can also be used as the first and second primary positioning anchor points, and Anchor A can be used as the first verification anchor point for verification.

[0088] Acquire real-time signal strength values, ranging success rates, and historical verification residuals for all anchor points and tags. Smooth the real-time signal strength values ​​to filter out instantaneous fluctuations; calculate the percentage of successful ranging operations for each anchor point within a recent period to obtain the ranging success rate; extract the average historical residuals when anchor points are used for verification. Using a preset weighting ratio, integrate the processed signal strength, ranging success rate, and historical residuals into an anchor point quality score; a higher score indicates better signal quality and stability of the anchor point.

[0089] A minimum signal strength threshold is preset. If the real-time signal strength of an anchor point is lower than this threshold, it is directly marked as an unusable primary anchor point, even if its score is high; it cannot be used as a primary positioning anchor point and can only be used temporarily for verification. All anchor points marked as unusable primary anchor points are filtered out, and only high- and low-priority available anchor points are selected. These available anchor points are then sorted from high to low quality scores, and the top two anchor points are selected to form a primary positioning anchor point group. The status of each anchor point in the primary anchor point group is continuously monitored. If the signal strength of any anchor point is lower than the preset threshold multiple times consecutively, or the ranging success rate is at a low level for a preset number of consecutive times, the anchor point is immediately marked as a temporary anomaly, and a new round of anchor point group selection process is triggered.

[0090] In this embodiment, by switching anchor points, when a human body occludes Anchor A, the system switches to B or C as the primary anchor points to avoid positioning blind spots. By polling different anchor point groups, even if there is non-line-of-sight interference in one direction, positioning can still be completed using line-of-sight signals from other directions.

[0091] Based on the first embodiment of this application, in the third embodiment of this application, the content that is the same as or similar to that in the first embodiment described above can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 3 After step S40, steps S50 to S100 are also included:

[0092] Step S50: Determine a second verification anchor point from the vertical plane of the first main positioning anchor point or the second main positioning anchor point, and determine the main positioning anchor point in the same vertical plane as the second verification anchor point as the target main positioning anchor point.

[0093] In this embodiment, the second verification anchor point is deployed either directly below the first main positioning anchor point or on the same vertical line, forming a known vertical baseline. For example, Anchor D, deployed directly below Anchor B, is used as the second verification anchor point. The Z-axis height information of the user tag is calculated by utilizing the vertical geometric difference with Anchor B.

[0094] Step S60: The distance between the second verification anchor point and the target main positioning anchor point is determined as the vertical baseline length; the distance between the user tag and the second verification anchor point is determined as the fourth measured distance; and the distance between the user tag and the main positioning anchor point is determined as the fifth measured distance.

[0095] Step S70: Determine the original height of the user tag based on the vertical baseline length, the fourth measured distance, and the fifth measured distance.

[0096] In this embodiment, since the second verification anchor point D and the target main positioning anchor point B are deployed on the same vertical line and have the same horizontal coordinates, the vertical baseline length = Z. B Z D The vertical distance between the two anchor points is obtained by subtracting the height of the bottom anchor point D from the height of the top anchor point B.

[0097] Calculate the original height of the label using the geometric relationship of the BD vertical baseline. Using Anchor B as the vertex, the distance from the user tag to B is the hypotenuse of a right triangle. One leg of this triangle is the horizontal distance from the tag to B, which is equal to the horizontal distance from the tag to D; the other leg is the height difference between the tag and B. Using Anchor D as the vertex, the distance from the user tag to D is also the hypotenuse of a right triangle. The horizontal legs of this triangle are exactly the same as the one above, and the other leg is the height difference between the tag and D. Since the horizontal legs of the two right triangles are equal in length, we combine the Pythagorean theorem relationship between the two triangles and eliminate the unknown quantity of horizontal distance by subtracting the squares, leaving only the calculation terms related to height. We subtract the square of the distance from anchor point B to the tag from the square of the distance from the second verification anchor point D, and add the square of the vertical baseline length between B and D to get a sum. Dividing this sum by twice the vertical baseline length and finally adding the height value of anchor point D, the result is the original height of the tag. Taking advantage of the vertically collinear deployment of B and D, the unknown quantity in the horizontal direction is eliminated by using the distance measurement values ​​of the two hypotenuses, and the vertical height is directly calculated.

[0098] The formula for calculating the original height is: .

[0099] Step S80: Compare the height difference between the original height and the height constraint value with a preset height difference threshold.

[0100] Step S90: If the height difference is less than the height difference threshold, then the original height is determined as the effective height.

[0101] In this embodiment, the height constraint value is derived from the original slope distance from the target's main positioning anchor point B to the user tag, based on the highly reliable first plane coordinates (x, y). The obtained original height and the height constraint value are compared. If the deviation between the two is within the allowable range, the original height is retained as the valid height.

[0102] In one feasible implementation, after step S80, the method may further include: if the height difference is greater than or equal to the height difference threshold, then the height constraint value is determined as the effective height, wherein the calculation formula for the height constraint value is:

[0103] ;

[0104] in, Z is the height constraint value. B Let d be the height coordinate of the main positioning anchor point. B This is the fifth measured distance. The horizontal distance between the first planar coordinates and the main positioning anchor point.

[0105] In this embodiment, the planar coordinates of anchor point B and the first planar coordinates form a right triangle on the XY plane, with the two legs representing the difference in the X-axis direction and the difference in the Y-axis direction, respectively; the hypotenuse is the horizontal straight-line distance R from the first planar coordinates to anchor point B. planar .

[0106] Therefore, the horizontal distance from the first plane coordinate to B is:

[0107] .

[0108] Anchor point B, the coordinates of the first plane, and the projection point of the first plane coordinates directly below (or above) anchor point B form a right-angled triangle in the vertical direction, with one leg being the horizontal distance. , which is the horizontal projection length from the first plane coordinate to the anchor point B; the other right-angled side is the height difference between the first plane coordinate and the anchor point B; the hypotenuse is the measured slope distance from the anchor point B to the user tag.

[0109] Therefore, the height constraint value is: .

[0110] When the height difference is greater than or equal to the height difference threshold, it indicates that the original height is affected by ground reflection and human occlusion, and fluctuates greatly. Therefore, a more reliable height constraint value is used as the final effective height.

[0111] Step S100: Based on the effective height and the second planar coordinates, obtain the target three-dimensional coordinates of the user tag.

[0112] In this embodiment, because point D is deployed at a low position, typically at the waist or bottom of the gate, it is easily obstructed, resulting in poor signal quality and large fluctuations in ranging accuracy. Therefore, this embodiment uses the high-confidence first plane coordinates to verify and correct the low-confidence height Z, ensuring the reliability of the height data.

[0113] In one feasible implementation, step S100 includes steps S110-140:

[0114] Step S110: Based on the effective height, determine the horizontal projected distance between the distance measurement values ​​of the first main positioning anchor point and the second main positioning anchor point.

[0115] Step S120: Based on the double-circle intersection algorithm and the horizontal projection distance, determine the coordinates of the third plane, as well as the first ordinate and the first abscissa in the third plane coordinates.

[0116] In this embodiment, the 2D positioning algorithm directly calculates the slant distance from the anchor point to the label as the horizontal distance, ignoring the height difference, which introduces errors. After obtaining the corrected effective height, the slant distance of each anchor point can be projected into a horizontal distance, and then the planar coordinates can be recalculated using a more accurate horizontal distance to obtain a more precise x and y position.

[0117] For each anchor point, calculate its horizontal projected distance:

[0118] .

[0119] Using the corrected horizontal projection distance, the double-circle intersection algorithm is re-executed to obtain more accurate third plane coordinates (x′, y′).

[0120] Step S130: Take the square root of the difference between the first ordinate and the square of the effective height to obtain the second ordinate.

[0121] In this implementation, in the turnstile scenario, the user's height will cause the calculated value of the Y-axis (distance between the user and the turnstile) to be too large, which can easily lead to the turnstile opening prematurely or misjudging the anti-pinch function. By using the corrected third-plane coordinates and the actual height, the true horizontal distance between the user and the turnstile is deduced, thereby eliminating the bias caused by height and making the turnstile's judgment more accurate.

[0122] The original Y-axis coordinate is the projection of the slant distance onto the plane, and it will be larger due to the height.

[0123] Using the Pythagorean theorem to deduce the true Y-axis distance: .

[0124] Step S140: Combine the first horizontal coordinate, the second vertical coordinate, and the effective height to obtain the target's three-dimensional coordinates.

[0125] In this embodiment, the first planar coordinates (x, y) of the tag are calculated first using the actual distance measurements of the top anchor points A and B (or B and C) combined with the physical constraints of the gate. Using these first planar coordinates (x, y), the horizontal distance from the tag to anchor point B is calculated, and then the slope distance from B to the tag is combined to obtain the height constraint value. This constraint value is compared with the original height directly calculated from anchor points B / D to finally determine the corrected effective height z. Using the effective height z obtained in the second step, the slope distances from all anchor points to the tag are converted into horizontal distances, and the planar coordinates are recalculated to obtain the second-corrected third planar coordinates (x', y'). The three-dimensional coordinates are then integrated, and the second-corrected third planar coordinates (x', y') are combined with the final effective height z to obtain the target three-dimensional coordinates (x', y', z) of the user tag.

[0126] In this embodiment, the 2D positioning algorithm directly calculates the slant distance from the anchor point to the label as the horizontal distance, ignoring the height difference, which introduces errors. The slant distance of each anchor point can be projected as a horizontal distance, and then the planar coordinates can be recalculated using this more accurate horizontal distance to obtain a more precise x and y position. Using the corrected planar coordinates and the actual height, the true horizontal distance from the user to the gate can be deduced, thereby eliminating the bias caused by height and making the gate's judgment more accurate.

[0127] Based on the first embodiment of this application, in the fourth embodiment of this application, the content that is the same as or similar to that in the first embodiment described above can be referred to the above description and will not be repeated hereafter. Based on this, after step S40, steps B10~B20 are also included:

[0128] Step B10: Smooth the target's three-dimensional coordinates based on a preset number of frames to obtain the coordinate trajectory of the user tag.

[0129] Step B20: Compare the coordinate trajectory with the preset valid passage area. If a preset number of consecutive frames are all within the valid passage area, then identity and payment authorization verification is triggered.

[0130] In this embodiment, a fixed-length sliding window buffer, such as 3-5 frames, is preset to retain only the target's 3D coordinates that have passed verification and have high confidence. When new valid coordinates arrive, they are added to the buffer, and the oldest frame of data is automatically removed to ensure that the buffer always contains the most recent multi-frame data. Each piece of data in the buffer has a precise timestamp to ensure the temporal correctness of subsequent trajectory calculations. A moving average is performed on the coordinates of consecutive frames in the buffer, or a Kalman filter algorithm is used to eliminate random fluctuations in single-frame positioning, resulting in a smoothed coordinate trajectory. For example: the smoothed coordinates of the current frame = 0.4 × current frame coordinates + 0.3 × previous frame coordinates + 0.2 × coordinates of the two previous frames + 0.1 × coordinates of the three previous frames.

[0131] Taking into account the physical boundaries of the turnstile channel (e.g., the X-axis must be within the channel width, and the Y-axis must be within the effective range before and after the turnstile), check whether the smoothed trajectory exceeds the channel width. Check whether the trajectory's movement direction conforms to the passage logic; for example, users should only be able to enter the channel along the positive Y-axis and leave along the negative Y-axis. Any reverse jump is considered abnormal. Abnormal trajectories are corrected, for example, by pulling coordinates that exceed the channel range back to the boundary, or discarding frames that do not conform to the movement direction, resulting in a smooth user movement trajectory estimate that conforms to physical laws.

[0132] Based on the fused smooth trajectory, the user's current position is determined. If the coordinates of a preset number of consecutive frames in the smooth trajectory continuously fall within the effective passage area of ​​the turnstile channel (X within the width, Y within the effective range before and after the turnstile), it is determined to be within the area. If the coordinates of the most recent preset number of consecutive frames in the smooth trajectory continuously fall outside the channel, or the movement direction indicates that the user is leaving the channel, i.e., the Y value continuously decreases, it is determined to be outside the area.

[0133] Step B30: If the verification is successful, control the gate to open.

[0134] In this embodiment, when a user is determined to be within the valid passage area, the identity verification process is triggered. The terminal and the gate control unit transmit identity information, such as device ID and user ID, through a UWB encrypted channel, and complete two-way authentication using a security chip. The control unit forwards the identity information to the AFC system to verify account validity, such as sufficient subway card balance, expired transit code, and no blacklist records. The system obtains a verification result confirming identity and payment authorization. Upon successful verification, an authorization signal is generated, and the AFC system sends an opening command to the gate control unit, including the target gate number and opening duration. The control unit drives the gate motor to open the corresponding gate and simultaneously illuminates the green passage indicator light. The gate's built-in infrared sensor monitors the passage status in real time; if there is a risk of people / objects being trapped, the opening is immediately paused or the gate is closed urgently. After detecting that the user has completely passed through, a passage completion signal is sent to the control unit, which then closes the gate. The AFC system (Automatic Fare Collection System) deducts the fare based on the entry and exit information and generates a transaction record.

[0135] This application provides an ultra-wideband positioning method device based on multi-anchor point collaboration, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to execute the ultra-wideband positioning method based on multi-anchor point collaboration described in Embodiment 1 above.

[0136] The following is for reference. Figure 4 The diagram illustrates a structural schematic of an ultra-wideband positioning method device suitable for implementing the embodiments of this application based on multi-anchor point collaboration. The ultra-wideband positioning method device based on multi-anchor point collaboration in the embodiments of this application may include, but is not limited to, mobile terminals such as mobile phones, laptops, personal digital assistants (PDAs), tablet computers (PADs), and in-vehicle terminals (e.g., in-vehicle navigation terminals), as well as main positioning terminals such as digital TVs and desktop computers. Figure 4The illustrated ultra-wideband positioning method device based on multi-anchor point collaboration is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this application.

[0137] like Figure 4 As shown, the device for the ultra-wideband positioning method based on multi-anchor point cooperation may include a processing unit 1001 (e.g., a central processing unit, a graphics processing unit, etc.) that performs various appropriate actions and processes according to a program stored in a read-only memory (ROM) 1002 or a program loaded from a storage device 1003 into a random access memory (RAM) 1004. The RAM 1004 also stores various programs and data required for the operation of the ultra-wideband positioning method device based on multi-anchor point cooperation. The processing unit 1001, the read-only memory 1002, and the RAM 1004 are interconnected via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to I / O interface 1006: input devices 1007 including, for example, touchscreens, touchpads, keyboards, mice, image sensors, microphones, accelerometers, gyroscopes, etc.; output devices 1008 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 1003 including, for example, magnetic tapes, hard disks, etc.; and communication devices 1009. Communication device 1009 allows the device based on multi-anchor-coordinated ultra-wideband positioning method to exchange data with other devices wirelessly or via wired communication. Although the figure shows a device based on multi-anchor-coordinated ultra-wideband positioning method with various systems, it should be understood that it is not required to implement or possess all the systems shown. More or fewer systems can be implemented alternatively.

[0138] Specifically, according to the embodiments disclosed in this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments disclosed in this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device, or installed from storage device 1003, or installed from read-only memory 1002. When the computer program is executed by processing device 1001, it performs the functions defined in the methods of the embodiments disclosed in this application.

[0139] The UWB positioning method and device based on multi-anchor point collaboration provided in this application, employing the UWB positioning method based on multi-anchor point collaboration in the above embodiments, can solve the technical problem of how to improve the accuracy of UWB positioning in subway gate scenarios. Compared with the prior art, the beneficial effects of the UWB positioning method and device based on multi-anchor point collaboration provided in this application are the same as those of the UWB positioning method based on multi-anchor point collaboration provided in the above embodiments, and other technical features in this UWB positioning method and device based on multi-anchor point collaboration are the same as those disclosed in the previous embodiment, and will not be repeated here.

[0140] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0141] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0142] This application provides a computer-readable storage medium having computer-readable program instructions (i.e., a computer program) stored thereon, the computer-readable program instructions being used to execute the ultra-wideband positioning method based on multi-anchor point cooperation in the above embodiments.

[0143] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems or devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, radio frequency (RF), etc., or any suitable combination thereof.

[0144] The aforementioned computer-readable storage medium may be included in a device for a multi-anchor-based ultra-wideband positioning method; or it may exist independently and not assembled into the device. The aforementioned computer-readable storage medium carries one or more programs that, when executed by the multi-anchor-based ultra-wideband positioning method device, cause the device to: locate a user tag based on a first primary positioning anchor point and a second primary positioning anchor point, obtaining the first planar coordinates of the user tag; determine a first verification anchor point from the same horizontal plane of the first primary positioning anchor point and the second primary positioning anchor point; determine a third measured distance between the first verification anchor point and the user tag, and a theoretical distance between the first planar coordinates and the first verification anchor point; when the absolute value of the difference between the theoretical distance and the third measured distance is determined as a residual, if the residual is less than a preset difference threshold, confirm the first planar coordinates as the second planar coordinates.

[0145] Computer program code for performing the operations of this application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the client computer, partially on the client computer, as a standalone software package, partially on the client computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the client computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0146] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0147] The modules described in the embodiments of this application can be implemented in software or hardware. The names of the modules do not necessarily limit the functionality of the unit itself.

[0148] The readable storage medium provided in this application is a computer-readable storage medium that stores computer-readable program instructions (i.e., a computer program) for executing the above-described ultra-wideband positioning method based on multi-anchor point cooperation. This addresses the technical problem of improving the accuracy of ultra-wideband positioning in subway gate scenarios. Compared with existing technologies, the beneficial effects of the computer-readable storage medium provided in this application are the same as those of the ultra-wideband positioning method based on multi-anchor point cooperation provided in the above embodiments, and will not be elaborated upon here.

[0149] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.

Claims

1. A multi-anchor point cooperative ultra-wideband positioning method, characterized in that, The ultra-wideband positioning method based on multi-anchor point cooperation includes: The user tag is located based on the first and second primary positioning anchor points to obtain the first planar coordinates of the user tag. The first verification anchor point is determined from the same horizontal plane of the first main positioning anchor point and the second main positioning anchor point; Determine the third measured distance between the first verification anchor point and the user tag, and the theoretical distance between the first planar coordinates and the first verification anchor point; When the absolute value of the difference between the theoretical distance and the third measured distance is determined as the residual, if the residual is less than a preset difference threshold, the first plane coordinates are confirmed as the second plane coordinates. From the vertical plane of the first primary positioning anchor point or the second primary positioning anchor point, determine the second verification anchor point, and determine the primary positioning anchor point in the same vertical plane as the second verification anchor point as the target primary positioning anchor point; The distance between the second verification anchor point and the target main positioning anchor point is determined as the vertical baseline length, the distance between the user tag and the second verification anchor point is determined as the fourth measured distance, and the distance between the user tag and the main positioning anchor point is determined as the fifth measured distance. The original height of the user tag is determined based on the vertical baseline length, the fourth measured distance, and the fifth measured distance. The height difference between the original height and the height constraint value is compared with a preset height difference threshold. If the height difference is less than the height difference threshold, then the original height is determined as the effective height; Based on the effective height and the second planar coordinates, the target three-dimensional coordinates of the user tag are obtained; The target's three-dimensional coordinates are smoothed based on a preset number of frames to obtain the coordinate trajectory of the user tag; The coordinate trajectory is compared with the preset valid passage area. If a preset number of consecutive frames are all within the valid passage area, identity and payment authorization verification is triggered. If the verification is successful, the gate will be opened.

2. The ultra-wideband positioning method based on multi-anchor point cooperation as described in claim 1, characterized in that, Before the step of locating the user tag based on the first primary positioning anchor point and the second primary positioning anchor point to obtain the first planar coordinates of the user tag, the ultra-wideband positioning method based on multi-anchor point collaboration further includes: Based on the user tag, ranging signals are sent to the first verification anchor point, the first primary positioning anchor point, and the second primary positioning anchor point respectively to obtain the third measured distance, the first measured distance between the first primary positioning anchor point and the user tag, and the second measured distance between the second primary positioning anchor point and the user tag.

3. The ultra-wideband positioning method based on multi-anchor point cooperation as described in claim 2, characterized in that, The step of locating the user tag based on the first primary positioning anchor point and the second primary positioning anchor point to obtain the first planar coordinates of the user tag includes: Two circles are generated, one with the first main positioning anchor point as the center and the other with the first measured distance as the radius, and the other with the second main positioning anchor point as the center and the other with the second measured distance as the radius. The coordinates of the intersection point of the two circles are determined as the potential plane coordinates; The coordinates in the potential plane coordinates where the vertical coordinate is positive and the horizontal coordinate is within the preset channel width range are determined as the first plane coordinates.

4. The ultra-wideband positioning method based on multi-anchor point cooperation as described in claim 1, characterized in that, Before the step of locating the user tag based on the first primary positioning anchor point and the second primary positioning anchor point to obtain the first planar coordinates of the user tag, the ultra-wideband positioning method based on multi-anchor point collaboration further includes: Determine the RSSI value, ranging success rate, and historical verification residual for each preset anchor point; The signal quality score is obtained by weighted summing of the RSSI value, the ranging success rate and the historical verification residual. The two preset anchor points with RSSI values ​​greater than a preset RSSI threshold and the highest signal quality scores are determined as the first primary positioning anchor point and the second primary positioning anchor point.

5. The ultra-wideband positioning method based on multi-anchor point cooperation as described in claim 1, characterized in that, After the step of comparing the height difference between the original height and the height constraint value with a preset height difference threshold, the ultra-wideband positioning method based on multi-anchor point collaboration further includes: If the height difference is greater than or equal to the height difference threshold, then the height constraint value is determined as the effective height, and the formula for calculating the height constraint value is: ， in, Z is the height constraint value. B Let d be the height coordinate of the main positioning anchor point. B This is the fifth measured distance. The horizontal distance between the first planar coordinates and the main positioning anchor point.

6. The ultra-wideband positioning method based on multi-anchor point cooperation as described in claim 1, characterized in that, The step of obtaining the target three-dimensional coordinates of the user tag based on the effective height and the second planar coordinates includes: Based on the effective height, determine the horizontal projected distance between the distance measurement values ​​of the first main positioning anchor point and the second main positioning anchor point; Based on the double-circle intersection algorithm and the horizontal projection distance, the coordinates of the third plane, as well as the first ordinate and the first abscissa in the third plane coordinates, are determined; The second ordinate is obtained by taking the square root of the difference between the first ordinate and the square of the effective height. The target's three-dimensional coordinates are obtained by combining the first horizontal coordinate, the second vertical coordinate, and the effective height.

7. An ultra-wideband positioning device based on multi-anchor point collaboration, characterized in that, The device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the ultra-wideband positioning method based on multi-anchor point collaboration as described in any one of claims 1 to 6.

8. A storage medium, characterized in that, The storage medium is a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements the steps of the ultra-wideband positioning method based on multi-anchor point cooperation as described in any one of claims 1 to 6.

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