Ranging value NLOS identification method and apparatus, and receiving apparatus and storage medium

Abstract

Provided in some of the embodiments of the present application are a ranging value NLOS identification method, a receiving apparatus, and a storage medium. The identification method comprises: acquiring a channel impulse response (CIR) of a channel corresponding to a ranging value; performing calculation on the basis of the CIR, so as to obtain a first-path location index and a strongest-path location index; obtaining a first-time NLOS state value of the ranging value on the basis of the first-path location index, the strongest-path location index and a preset NLOS state level; and acquiring at least two types of NLOS level correction parameters of the ranging value, and successively correcting the NLOS state value of the ranging value on the basis of the at least two types of NLOS level correction parameters, so as to obtain a final NLOS state value of the ranging value, wherein the at least two types of NLOS level correction parameters are selected from among the following correction parameters: a first-path power and a received power which correspond to the ranging value, motion speed information of a ranging target corresponding to the ranging value, a reference of an NLOS level of the ranging value, and the ranging value and information of edges of a triangle corresponding to the ranging value. (FIG. 2)

Description

Ranging value NLOS identification method and device, receiving device and storage medium Technical Field

[0001] The present application relates to the field of communications technology, and more particularly to a method and apparatus for identifying NLOS values ​​for ranging values, a receiving device, and a storage medium. This application references Chinese patent application No. 202410027771.3, filed on January 9, 2024, entitled “Method and apparatus for identifying NLOS values ​​for ranging values, a receiving device, and a storage medium,” which is incorporated herein by reference in its entirety. Background Art

[0002] With the advancement of technology, location-based services (LBS) have brought significant convenience to daily life. Location-based services primarily encompass indoor and outdoor positioning. Outdoor GPS (Global Positioning System) positioning is relatively mature and can meet people's outdoor positioning needs. However, indoors, GPS cannot provide high-precision positioning due to obstruction of satellite signals. Since most human activities occur indoors, research on high-precision indoor positioning is highly relevant. Compared to other wireless positioning technologies, ultra-wideband (UWB) positioning offers high positioning accuracy, extremely wide bandwidth, enhanced security, strong penetration, and robust anti-interference capabilities, making UWB positioning considered one of the most promising indoor positioning solutions. Technical issues

[0003] The ranging value in a non-line-of-sight (NLOS) channel environment is often more than 1 meter larger than the actual distance, and the ranging value fluctuates greatly. If the ranging value in NLOS is used to calculate the tag coordinates, the calculated tag coordinates will deviate significantly from the actual coordinates. Therefore, it is very necessary to identify the ranging value in the NLOS channel environment. Existing methods for identifying NLOS ranging values ​​mainly include: 1. NLOS identification based on channel impulse response (CIR), which intercepts the CIR sequence received by the receiver and processes the intercepted CIR fragment to obtain the position index of the first path, thereby correcting the ranging value. This method is prone to misjudgment of the first path position; 2. NLOS judgment based on the residual method, which first uses the ranging value to solve the coordinate solution, and then obtains the deviation between the distance of the solved coordinate to the base station and the corresponding ranging value. This deviation is the residual. If the residual is greater than the threshold, the corresponding ranging value is NLOS, and the coordinates are then recalculated using the non-NLOS ranging value. This method has a large amount of calculation and is time-consuming; 3. NLOS judgment based on artificial intelligence, which establishes a model through NLOS data collection, training, and prediction. This method is time-consuming and inefficient. Technical Solutions

[0004] The purpose of some embodiments of the present application is to provide a ranging value NLOS identification method and device, a receiving device and a storage medium, which can accurately and efficiently identify the NLOS state of the ranging value, which is conducive to improving the stability of positioning under NLOS. The method is simple, has a small amount of calculation, and is easy to implement.

[0005] In a first aspect, an embodiment of the present invention provides a method for identifying NLOS of a ranging value, comprising: obtaining a channel impulse response (CIR) of a channel corresponding to the ranging value; calculating a first path position index and a strongest path position index based on the CIR; obtaining a first NLOS state value of the ranging value based on the first path position index, the strongest path position index, and a preset NLOS state level; obtaining at least two NLOS level correction parameters for the ranging value, and sequentially correcting the NLOS state value of the ranging value based on the at least two NLOS level correction parameters to obtain a final NLOS state value of the ranging value; wherein the at least two NLOS level correction parameters are selected from the following correction parameters: a first path power and a received power corresponding to the ranging value, motion speed information of a ranging target corresponding to the ranging value, a reference benchmark for the NLOS level of the ranging value, and information about the ranging value and the sides of its corresponding triangle.

[0006] In a second aspect, an embodiment of the present invention provides a ranging value NLOS identification device, comprising: a CIR acquisition module, configured to acquire a channel impulse response CIR of a channel corresponding to the ranging value;

[0007] A position calculation module, configured to calculate a first path position index and a strongest path position index according to the CIR;

[0008] a first identification module, configured to obtain a first NLOS status value of the ranging value according to the first path position index, the strongest path position index, and a preset NLOS status level; and

[0009] a correction module, configured to obtain at least two NLOS level correction parameters for the ranging value, and sequentially correct the NLOS state value of the ranging value according to the at least two NLOS level correction parameters to obtain a final NLOS state value of the ranging value; wherein the at least two NLOS level correction parameters are selected from the following correction parameters: head path power and received power corresponding to the ranging value, motion speed information of a ranging target corresponding to the ranging value, a reference benchmark of the NLOS level of the ranging value, and information about the ranging value and the sides of its corresponding triangle.

[0010] In a third aspect, an embodiment of the present invention provides a receiving device, including a memory, a transceiver, and a processor;

[0011] A memory for storing a computer program; a transceiver for transmitting and receiving data under the control of the processor; and the processor for reading the computer program in the memory and implementing the aforementioned ranging value NLOS identification method when executing the program.

[0012] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the ranging value NLOS identification method as described in the first aspect. Beneficial effects

[0013] The ranging value NLOS identification method of the embodiment of the present invention first obtains the first NLOS state value of the ranging value based on the first diameter position index and the strongest diameter position index of the ranging value, and then successively corrects the NLOS state value of the ranging value based on at least two NLOS level correction parameters, thereby accurately and efficiently obtaining the NLOS state of the ranging value through multi-dimensional evaluation. The method is simple, has a small computational complexity, is easy to implement, is suitable for indoor UWB positioning, and can improve the stability of UWB positioning. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG1 is a flow chart of a method for identifying NLOS ranging values ​​according to a first embodiment of the present invention;

[0015] FIG2 is a flow chart of a method for identifying NLOS ranging values ​​according to a second embodiment of the present invention;

[0016] Figure 3 is a schematic diagram of UWB positioning bilateral two-way ranging;

[0017] FIG4 is a flow chart of a method for identifying NLOS ranging values ​​according to a third embodiment of the present invention;

[0018] Figure 5 is a schematic diagram of TOA positioning;

[0019] Figure 6 is a schematic diagram of TDOA clock synchronization;

[0020] Figure 7 is a schematic diagram of an uplink TDOA clock;

[0021] FIG8 is a schematic structural diagram of a ranging value NLOS identification device provided in a fourth embodiment of the present invention;

[0022] FIG9 is a schematic structural diagram of a receiving device provided in Embodiment 5 of the present invention. Best Mode for Carrying Out the Invention

[0023] The best implementation may be one of the following implementations, which will not be described in detail here. Modes for Carrying Out the Invention

[0024] FIG1 is a flow chart of a method for identifying NLOS of a ranging value provided in accordance with a first embodiment of the present invention. The method is applied to a receiving end to accurately identify the NLOS state of a ranging value and can be applied to ultra-wideband (UWB) positioning, laser ranging, and the like. The receiving end can be an ultra-wideband (UWB) base station or a laser ranging receiving device, and is not specifically limited here. The method can be performed by a ranging value NLOS identification device provided in accordance with an embodiment of the present invention, which can be implemented in software and / or hardware and configured at the receiving end. The embodiment of the present invention specifically includes the following steps:

[0025] Step 101: Obtain a channel impulse response (CIR) of a channel corresponding to a ranging value.

[0026] The ranging value is the distance between the UWB tag and the UWB base station, as measured by the UWB base station. The channel corresponding to the ranging value is the communication channel between the UWB base station and the UWB tag during ranging. The channel impulse response reflects the basic characteristics of the channel. CIR data can be read from the UWB base station chip and will not be further described here.

[0027] Step 102: Calculate the first path position index and the strongest path position index according to the CIR.

[0028] During UWB ranging, the receiver calculates the first path position index and the strongest path position index from the CIR information of each ranging packet. Those skilled in the art can use known methods to obtain the first path position index and the strongest path position index, which will not be repeated here.

[0029] Step 103: Obtain the first NLOS state value of the ranging value according to the first path position index, the strongest path position index, and the preset NLOS state level.

[0030] The NLOS status level indicates multiple possibilities of the channel environment of the channel corresponding to the ranging value being a line-of-sight environment LOS or a non-line-of-sight environment NLOS. For example, the level of the ranging value LOS may include two levels: the ranging value is LOS or the ranging value is likely to be LOS. The level of the ranging value NLOS may include two levels: the ranging value is NLOS and the ranging value is likely to be NLOS. It is understandable that the NLOS status level can be pre-divided and can be divided into finer granularity, and no excessive restrictions are made here.

[0031] Obtaining the first NLOS status value of the ranging value according to the first path position index, the strongest path position index and the preset NLOS status level may specifically include: obtaining the first NLOS status value of the ranging value according to the difference between the first path position index and the strongest path position index and the preset NLOS status level.

[0032] It should be noted that, based on the difference between the first path position index and the strongest path position index, it is possible to accurately identify situations where the ranging value is LOS, the ranging value is likely to be LOS, or the ranging value is likely to be NLOS, which is conducive to further accurate classification of situations where the ranging value is not LOS in subsequent corrections.

[0033] Step 104: Obtain at least two NLOS level correction parameters of the ranging value, and correct the NLOS state value of the ranging value in sequence according to the at least two NLOS level correction parameters to obtain a final NLOS state value of the ranging value.

[0034] The NLOS level correction parameter is used to compensate for the deviation in the NLOS status value identification of the ranging value. Different NLOS level correction parameters can compensate the NLOS status value of the ranging value from different dimensions. Multiple NLOS level correction parameters can more comprehensively correct the NLOS status value and improve the accuracy of NLOS identification of the ranging value.

[0035] Among them, at least two NLOS level correction parameters are selected from the following correction parameters: the first path power and the received power corresponding to the ranging value, the motion speed information of the ranging target corresponding to the ranging value, the reference benchmark of the NLOS level of the ranging value, and the information of the ranging value and the side of the corresponding triangle.

[0036] Two of the aforementioned NLOS level correction parameters can be used, such as the head path power and received power corresponding to the ranging value and the speed information of the ranging target corresponding to the ranging value, to sequentially correct the final NLOS state value of the ranging value. Alternatively, three or all correction parameters can be used to perform corrections sequentially. It should be understood that this embodiment does not impose excessive restrictions on the number, sequence, and specific correction parameters. Other correction parameters may also be used based on the characteristics of the channel environment and the ranging environment.

[0037] When the NLOS level correction parameters are the first path power and received power corresponding to the ranging value, the NLOS status value of the ranging value can be corrected based on the difference between the first path power and the received power. The first path power is the power corresponding to the first path index, such as the power corresponding to the first path index searched by the TOA algorithm; the received power is the total received power calculated by the receiver. Correcting based on the difference between the first path power and the received power of the ranging value helps further identify ranging values ​​under LOS conditions where the first path is not the strongest path.

[0038] When the NLOS level correction parameter is the motion speed information of the ranging target corresponding to the ranging value, the maximum distance difference threshold of adjacent ranging values ​​can be obtained according to the ranging frequency and the maximum motion speed of the ranging target. The NLOS status value of the ranging value is corrected according to the maximum distance difference threshold, which is conducive to more accurate and effective identification of the channel environment based on the motion information of the ranging target.

[0039] When the NLOS level correction parameter is a reference benchmark for the NLOS level of the ranging value, a reference benchmark (also called a baseline) for the NLOS level of the ranging value can be established, and the NLOS status value of the ranging value can be corrected based on the average value and / or standard deviation of n ranging values ​​in the reference benchmark. The reference benchmark includes n ranging values ​​that continuously meet preset conditions, thereby more accurately identifying the NLOS status of the ranging value based on the statistical characteristics of the ranging value, such as inertia.

[0040] When the NLOS level correction parameter is information about the distance measurement value and its corresponding triangle side, the NLOS state value of the distance measurement value can be corrected based on the distance measurement value, its corresponding triangle side information, and the relationship between the three sides of the triangle, thereby further improving the accuracy of NLOS state recognition. The correction method for each of the above correction parameters is described in detail below.

[0041] Compared with the prior art, the ranging value NLOS identification method of the embodiment of the present invention first obtains the first NLOS state value of the ranging value based on the first diameter position index and the strongest diameter position index of the ranging value, and then successively corrects the NLOS state value of the ranging value based on multiple NLOS level correction parameters. Thus, through multi-dimensional analysis, the NLOS state of the ranging value is accurately and efficiently obtained. The method is simple, has a small amount of calculation, is easy to implement, is suitable for indoor UWB positioning, and can improve the stability of UWB positioning.

[0042] A second embodiment of the present invention provides a method for identifying NLOS ranging values, comprising the following steps:

[0043] Step 201: Obtain a channel impulse response (CIR) of a channel corresponding to a ranging value.

[0044] Step 202: Calculate the first path position index and the strongest path position index based on the CIR.

[0045] Step 203: Obtain the first NLOS state value of the ranging value according to the difference between the first path position index and the strongest path position index and the preset NLOS state level.

[0046] The preset NLOS state level state values ​​are state = 0, 1, 2, and 3; where 0, 1, 2, and 3 respectively indicate that the channel environment of the ranging value is line-of-sight (LOS), likely LOS, likely NLOS, or NLOS. It is understood that the state value can be further divided into finer granularity, which is not specifically limited here.

[0047] As shown in FIG3 , the ranging value in this embodiment is obtained based on bilateral bidirectional UWB ranging. It is understandable that the ranging value can also be obtained based on unilateral bidirectional, and no specific limitation is made here. Step 203 obtains the first NLOS state value of the ranging value based on the difference between the first diameter position index and the strongest diameter position index and the preset NLOS state level, which may specifically include: if the index difference between the first diameter position index and the strongest diameter position index of the three ranging packets of the ranging value is less than the index difference threshold, then the state of the ranging value is 0; if the index difference between the first diameter position index and the strongest diameter position index of one or two of the three ranging packets is less than the index difference threshold, then the state of the ranging value is 1; if the index difference between the first diameter position index and the strongest diameter position index of the three ranging packets of the ranging value is greater than or equal to the index difference threshold, then the state of the ranging value is 2.

[0048] During ranging, three ranging packets—poll, response, and final—are transmitted between the tag and the anchor. The tag transmits its own CIR to the anchor, allowing the anchor to obtain the CIRs of the three ranging packets, as well as the first path position index and the strongest path position index for each CIR packet. If the difference between the first path position index and the strongest path position index (referred to as the index difference) in the CIR information of the three ranging packets at the receiving end (in the direction indicated by the arrow in the figure) is less than the index difference threshold, then state = 0, indicating that the NLOS state of the ranging value is considered to be LOS. If the index difference of one or two of the three ranging packets is less than the threshold, state = 1, indicating that the NLOS state of the ranging value is likely LOS. If the index difference of all three ranging packets is greater than or equal to the threshold, state = 2, indicating that the NLOS state of the ranging value is likely NLOS. This step indicates that when the first path is the strongest path, the ranging value is in the state of LOS, so the threshold is usually small, for example, it can be set to an integer less than 3. This embodiment does not impose any specific restrictions on the value of the threshold.

[0049] Step 204: Correct the NLOS status value of the ranging value according to the difference between the first path power and the received power of the ranging value.

[0050] Specifically, step 204 may include: if the state of the ranging value before this correction is 2, and the difference between the first path power and the received power of the three ranging packets of the ranging value is less than the power difference threshold corresponding to the received power of each packet, then the state of the corrected ranging value is 1; if the difference between the first path power and the received power of the three ranging packets of the ranging value is greater than or equal to the power difference threshold corresponding to the received power of each packet, then the state of the ranging value is 2.

[0051] Because the received power varies at different distances, the power difference threshold for each segment can be set based on the received power, generating a power difference threshold table for query. For the ranging value of state = 2 before correction, if the difference between the first path power and the received power of the three ranging packets is less than the power difference threshold corresponding to the received power of each packet, then state = 1. Conversely, if the difference between the first path power and the received power of the three ranging packets is greater than or equal to the power difference threshold corresponding to the received power of each packet, then state = 2, thereby updating the first NLOS state value and obtaining the second NLOS state value. This step can identify ranging values ​​under LOS conditions where the first path is not the strongest path. In this case, the CIR information contains a strong interference signal, but the first path can still be identified.

[0052] Step 205 : obtaining a maximum distance difference threshold between adjacent ranging values ​​according to the ranging frequency and the maximum moving speed of the ranging target, and correcting the NLOS status value of the ranging value according to the maximum distance difference threshold.

[0053] Specifically, step 205 may include: if d_now-d_before> , then state_now=3, that is, when the increase in the distance value exceeds the target maximum speed, it is considered that there is occlusion, and the distance value is identified as NLOS; if state_now=2&&d_now <d_before+ If / 4 && state_before <= 1, then state_now = 1. That is, when it is considered that the ranging value is likely to be NLOS before correction, but the difference between the current ranging value and the previous ranging value is less than one-fourth of the maximum distance difference threshold of adjacent ranging values, and the NLOS state value state_before of the ranging value before that is likely to be LOS, it is considered that the ranging value is likely to be LOS after correction, thereby reducing the recognition error. If state_before = 3 && d_now > d_before, state_now = 3. That is, when the NLOS state of the previous ranging value is NLOS and the current ranging value is greater than the previous ranging value, the current ranging value is considered to be NLOS. Here, d_now is the current ranging value, d_before is the previous ranging value, state_now is the NLOS state value of the current ranging value, and state_before is the NLOS state value of the previous ranging value. is the maximum distance difference threshold of adjacent ranging values.

[0054] Step 206: Establish a reference benchmark for the NLOS level of the ranging value, and correct the NLOS state value of the ranging value according to the average value and standard deviation of n ranging values in the reference benchmark.

[0055] Specifically, step 206 may include: If the states of n ranging values are all 0 or 1, when state_now = 2 for the (n + 1)-th ranging value, calculate the average value value_mean and standard deviation value_std of the 2nd to (n + 1)-th ranging values.

[0056] If abs(d_now - value_mean) < threshold_mean && value_std < threshold_std, then state_now = 1 for the ranging value after this correction. Here, threshold_mean represents the threshold of the difference between the average value of the ranging values in the reference benchmark window and the current ranging value, and threshold_std represents the threshold of the standard deviation of n ranging values in the reference benchmark window. Here, n can be 10, and the size of n is not specifically limited as long as it is conducive to accurately identifying the non-NLOS situation. threshold_mean and threshold_std = g(f, v, n) are both related to the ranging frequency f, the speed v of the ranging target, and the value of n. It can be understood that the variance can also be used instead of the standard deviation, which is not specifically limited here. Correcting the NLOS state value of the ranging value according to the statistical characteristics of the ranging value can effectively improve the accuracy of NLOS recognition of the ranging value.

[0057] Step 207: Correct the NLOS status value of the ranging value according to the ranging value and the information of the side of the corresponding triangle and the relationship between the three sides of the triangle.

[0058] Specifically, step 207 may include: if the ranging value , ranging value are the distances between the ranging target and the first base station and the second base station respectively, and and The absolute value of the difference is greater than the distance between the first base station and the second base station. , then the distance value If state=3, , then the distance value The state of the triangle is 3. Step 207 uses the triangle side length relationship (the difference between two sides is less than the third side) to perform the last NLOS state update, thereby obtaining the final NLOS state value.

[0059] Assume that the coordinates of base station 1 are ( ), the coordinates of base station 2 are ( ), the distance values ​​between the tag and base station 1 and base station 2 are 、 , ranging value 、 The NLOS states are state1 and state2. When, if , then state1=3; if , then state2 = 3. This further improves the accuracy of identifying NLOS states for ranging values ​​based on the relationship that the difference between two triangle sides is less than the third side. The NLOS state of ranging values ​​provides a valuable reference for coordinate calculation for TOA positioning in UWB. When calculating coordinates, different weights are assigned to ranging values. For example, state = 0 selects the highest weight, state = 1 the second highest weight, state = 2 the lowest weight, and state = 3 has a weight of 0. This effectively reduces positioning errors caused by ranging values ​​in NLOS conditions.

[0060] It should be noted that this embodiment is only a preferred embodiment. In some examples, the type, number and order of the correction parameters can be adjusted.

[0061] Compared with the prior art, the embodiment of the present invention first obtains the initial NLOS state value through the first path position index and the strongest path position index of the ranging value, and then sequentially corrects the NLOS state value of the ranging value from different dimensions through the difference between the first path power and the received power, the motion speed information of the ranging target, the reference benchmark of the NLOS level of the ranging value, and the relationship between the three sides of the triangle, thereby more accurately and effectively identifying the NLOS state. The embodiment of the present invention has simple calculation, small calculation amount, and is easy to implement. It is suitable for UWB indoor positioning and can significantly improve the stability of UWB positioning.

[0062] As shown in FIG4 , the third embodiment of the present invention further provides a ranging value NLOS identification method, including steps 401 to 404 .

[0063] Steps 401 to 403 are identical to the corresponding steps in the aforementioned embodiment and are not further described here. Step 403 yields the final NLOS status value of the ranging value. In step 404, different weights can be assigned to the ranging value based on the NLOS status value in the TOA or TDOA, thereby improving the accuracy of UWB positioning.

[0064] [Corrected 12.06.2024 according to Rule 26] As shown in Figure 5, the UWB Time Of Arrival (TOA) positioning diagram, assuming that the ranging values ​​of the tag to base stations A1, A2, A3, and A4 are 、 、 、 , the coordinates of base stations A1, A2, A3, and A4 are A1 ( ),A2( ),A3( ),A4( ).

[0065] [Corrected 12.06.2024 according to Rule 26] Establish label coordinates ( ) positioning equation.

[0066] [Corrected 12.06.2024 in accordance with Article 26]

[0067] [Corrected 12.06.2024 in accordance with Article 26] (1)

[0068] [Corrected 12.06.2024 in accordance with Article 26]

[0069] [Corrected 12.06.2024 in accordance with Article 26]

[0070] [Corrected 12.06.2024 according to Rule 26] The optimization goal of the linear least squares method is to minimize the square error, and its objective function is:

[0071] [Corrected 12.06.2024 in accordance with Article 26]

[0072] [Corrected 12.06.2024 in accordance with Rule 26] is the number of base stations;

[0073] [Corrected 12.06.2024 in accordance with Article 26] For label and distance estimation of base stations;

[0074] [Corrected 12.06.2024 in accordance with Article 26] For labels to The actual distance between the base stations;

[0075] [Corrected 12.06.2024 according to Rule 26] The coordinates of the label are , the coordinates of each base station are , the distance measurement value from the tag to each base station is . Then we have the equations:

[0076] [Corrected 12.06.2024 in accordance with Article 26] (2)

[0077] [Corrected 12.06.2024 according to Rule 26] In a two-dimensional positioning system, z and are all known (can be defined as ).

[0078] [Corrected 12.06.2024 in accordance with Rule 26] then:

[0079] [Corrected 12.06.2024 in accordance with Article 26] (3)

[0080] [Corrected 12.06.2024 according to Rule 26] Subtract the first equation from the second equations,

[0081] [Corrected 12.06.2024 in accordance with Article 26]

[0082] [Corrected 12.06.2024 in accordance with Article 26] (4)

[0083] [Corrected 12.06.2024 in accordance with Rule 26] Definitions,

[0084] [Corrected 12.06.2024 in accordance with Article 26]

[0085] [Corrected 12.06.2024 in accordance with Article 26]

[0086] [Corrected 12.06.2024 in accordance with Article 26] (5)

[0087] [Corrected 12.06.2024 according to Rule 26] The form of the system of equations:

[0088] [Corrected 12.06.2024 in accordance with Article 26] (6)

[0089] [Corrected 12.06.2024 according to Rule 26] When M=3, there are only 2 equations, and the unknowns are Theoretically, the equations are solvable if there are two values. However, in the presence of ranging errors, the equations may have no solution.

[0090] [Corrected 12.06.2024 according to Rule 26] When M is greater than 3, the generalized inverse of the matrix can be used to solve , and we get the LS solution.

[0091] [Corrected 12.06.2024 in accordance with Article 26]

[0092] [Corrected 12.06.2024 in accordance with Article 26]

[0093] [Corrected 12.06.2024 in accordance with Article 26]

[0094] [Corrected 12.06.2024 in accordance with Article 26] (7)

[0095] [Corrected 12.06.2024 in accordance with Rule 26] Among them, ;

[0096] Weighted least squares is a mathematical optimization technique that weights the original model to make it a new model without heteroskedasticity, and then uses ordinary least squares to estimate its parameters.

[0097] A diagonal matrix W is added on the basis of the least squares method, and different weights are assigned according to the final NLOS state value of each ranging value. The weight allocation method is not described here.

[0098] [Corrected 12.06.2024 in accordance with Article 26]

[0099] [Corrected 12.06.2024 in accordance with Article 26] Represents the square of the weight of the mth ranging value.

[0100] Adding the matrix W to formula (7) yields the solution of the equation

[0101] [Corrected 12.06.2024 in accordance with Article 26] (8)

[0102] The above method can effectively reduce the impact of NLOS ranging values ​​on the calculated coordinates, thereby improving the stability and accuracy of positioning.

[0103] UWB's Time Difference of Arrival (TDOA) positioning is based on the time difference of signal arrival. TDOA includes clock synchronization and time difference calculation.

[0104] Clock synchronization involves synchronizing the clocks of all base stations in a TDOA positioning system to the master base station's clock. Figure 6 shows a schematic diagram of TDOA clock synchronization. A0 is the master base station, and A1 and A2 are slave base stations. A0 sends synchronization frames to A1 and A2, which then record the time they receive the frames. If a synchronization frame encounters an NLOS (non-local orbit) in the air, the time it is received by the slave base station will be delayed, resulting in significant clock synchronization errors.

[0105] [Corrected 12.06.2024 according to Rule 26] As shown in the uplink TDOA clock diagram in Figure 7, after clock synchronization, the tag sends a positioning frame to each base station. Assume that the time when base stations A0, A1, and A2 receive the positioning frame are t0, t1, and t2 respectively. The coordinates of base stations A0, A1, and A2 are ( ),( ),( ), establish label coordinates ( ) positioning equation.

[0106] [Corrected 12.06.2024 in accordance with Article 26]

[0107] [Corrected 12.06.2024 in accordance with Article 26]

[0108] If there is NLOS in the path of the positioning frame flying in the air, the time when the base station receives the positioning frame will be delayed, which will inevitably lead to a large deviation in the positioning result.

[0109] If the NLOS judgment of the above steps 203, 204, and 205 is performed on the CIR information of the received synchronization frame or positioning frame, and the positioning weight of the time difference in the TDOA positioning equation group is determined by the NLOS status level, the use of weighted least squares method to solve the TDOA positioning equation can effectively reduce the positioning deviation caused by NLOS.

[0110] Compared with the prior art, the ranging value NLOS identification method of the embodiment of the present invention can accurately and efficiently obtain the NLOS state of the ranging value. The method is simple, has a small amount of calculation, is easy to implement, is suitable for indoor UWB positioning, and can improve the stability of UWB positioning.

[0111] The fourth embodiment of the present invention provides a ranging value NLOS identification device, which is configured at a receiving end, specifically a UWB base station. As shown in FIG8 , the ranging value NLOS identification device includes: a CIR acquisition module 802 , a position calculation module 804 , an initial identification module 806 , and a correction module 808 .

[0112] The CIR acquisition module 802 is configured to acquire a channel impulse response (CIR) of a channel corresponding to a ranging value.

[0113] The position calculation module 804 is configured to calculate the first path position index and the strongest path position index according to the CIR.

[0114] The first identification module 806 is configured to obtain the first NLOS state value of the ranging value according to the first path position index, the strongest path position index, and a preset NLOS state level.

[0115] Correction module 808 is configured to obtain at least two NLOS level correction parameters for the ranging value, and sequentially correct the NLOS state value of the ranging value based on the at least two NLOS level correction parameters to obtain a final NLOS state value of the ranging value. The at least two NLOS level correction parameters are selected from the following correction parameters: head path power and received power corresponding to the ranging value, velocity information of the ranging target corresponding to the ranging value, a reference NLOS level for the ranging value, and information about the ranging value and the sides of its corresponding triangle.

[0116] Optionally, the first identification module 806 is specifically configured to obtain the first NLOS state value of the ranging value according to the difference between the first path position index and the strongest path position index and a preset NLOS state level.

[0117] In this embodiment, the state value state=0, 1, 2, 3 of the preset NLOS state level; wherein 0, 1, 2, 3 respectively indicate that the channel scenario of the ranging value is line-of-sight environment LOS, very likely LOS, very likely NLOS, or NLOS.

[0118] The first identification module 806 is specifically configured to: if the ranging value is obtained based on bilateral bidirectional ranging, and the index differences between the first diameter position index and the strongest diameter position index of the three ranging packets of the ranging value are all less than the index difference threshold, then the state of the ranging value is 0; if the index difference between the first diameter position index and the strongest diameter position index of one or two of the three ranging packets is less than the index difference threshold, then the state of the ranging value is 1; if the index difference between the first diameter position index and the strongest diameter position index of the three ranging packets of the ranging value is all greater than or equal to the index difference threshold, then the state of the ranging value is 2.

[0119] The correction module 808 may include: a first submodule, configured to correct the NLOS state value of the ranging value according to the difference between the first path power and the received power of the ranging value when the NLOS level correction parameter is the first path power and the received power corresponding to the ranging value. Specifically, the first submodule may be configured to: if the ranging value is obtained based on bilateral two-way ranging, the state of the ranging value before this correction is 2, and the difference between the first path power and the received power of the three ranging packets of the ranging value is less than the difference threshold corresponding to the received power of each packet, then the state of the corrected ranging value is 1; if the difference between the first path power and the received power of the three ranging packets of the ranging value is greater than or equal to the difference threshold corresponding to the received power of each packet, then the state of the ranging value is 2.

[0120] The correction module 808 may further include: a second submodule for, when the NLOS level correction parameter is the movement speed information of the ranging target corresponding to the ranging value, obtaining a maximum distance difference threshold between adjacent ranging values ​​based on the ranging frequency and the maximum movement speed of the ranging target, and correcting the NLOS status value of the ranging value based on the maximum distance difference threshold. Specifically, the second submodule may be used if d_now-d_before> , then state_now=3; if state_now=2&&d_now <d_before+ / 4&&state_before<=1, then state_now=1; if state_before=3&&d_now>d_before, state_now=3; where d_now is the current ranging value, d_before is the last ranging value; state_now is the NLOS state value of the current ranging value, state_before is the NLOS state value of the last ranging value, is the maximum distance difference threshold for adjacent ranging values.

[0121] The correction module 808 may further include: a third sub-module, configured to establish a reference benchmark for the NLOS level of the ranging value when the NLOS level correction parameter is the reference benchmark for the NLOS level of the ranging value, and correct the NLOS status value of the ranging value according to the average value and / or standard deviation of n ranging values in the reference benchmark; wherein the reference benchmark includes n consecutive ranging values that meet a preset condition; n is a natural number greater than 1.

[0122] Specifically, the third sub-module is configured to: if the state of n ranging values is all 0 or 1, when the state_now of the (n + 1)-th ranging value is 2, calculate the average value value_mean and the standard deviation value_std of the second to the (n + 1)-th ranging values; if abs(d_now - value_mean) < threshold_mean && value_std < threshold_std, then the state_now of the ranging value after this correction is 1; wherein, threshold_mean represents the threshold of the difference between the average value of the ranging values in the reference benchmark window and the current ranging value, and threshold_std represents the threshold of the standard deviation of n ranging values in the reference benchmark window; wherein, threshold_mean and threshold_std = g(f, v, n) are both related to the ranging frequency f, the speed v of the ranging target, and the value of n.

[0123] The correction module 808 may further include: a fourth sub-module, configured to correct the NLOS status value of the ranging value according to the ranging value, the information of the sides of the corresponding triangle, and the relationship between the three sides of the triangle when the NLOS level correction parameter is the ranging value and the information of the sides of the corresponding triangle. Specifically, the fourth sub-module may be configured to if the ranging value , the ranging value are respectively the distances between the ranging target and the first base station and the second base station, and the difference between and has an absolute value greater than the distance between the first base station and the second base station, if , then the state of the ranging value is 3, if , then the state of the ranging value

[0124] The correction module 808 may perform corrections sequentially in the following order: the first-path power and received power corresponding to the ranging value, the motion speed information of the ranging target corresponding to the ranging value, the reference benchmark for the NLOS level of the ranging value, and the ranging value and the information of the sides of the corresponding triangle.

[0125] The ranging value NLOS identification device may further include a positioning module (not shown) configured to perform TOA or TDOA positioning based on the final NLOS state value of the ranging value.

[0126] Compared with the prior art, the ranging value NLOS identification device of the embodiment of the present invention first obtains the first NLOS state value of the ranging value based on the first diameter position index and the strongest diameter position index of the ranging value, and then successively corrects the NLOS state value of the ranging value based on multiple NLOS level correction parameters. Thus, through multi-dimensional analysis, the NLOS state of the ranging value is accurately and efficiently obtained. The method is simple, has a small amount of calculation, is easy to implement, is suitable for indoor UWB positioning, and can improve the stability of UWB positioning.

[0127] Figure 9 is a schematic diagram of the structure of a receiving device provided in Embodiment 5 of the present invention. The receiving device 90 includes a memory 91, a transceiver 93, and a processor 92;

[0128] The memory 91 is used to store computer programs; the transceiver 93 is used to send and receive data under the control of the processor; the processor 92 is used to read the computer program in the memory 91 and implement the ranging value NLOS identification method as described in the above embodiment when executing the program.

[0129] A sixth embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a computer processor, the computer program is used to execute the technical solution of any method embodiment.

[0130] It is worth noting that in the embodiment of the above-mentioned device, the various units and modules included are only divided according to functional logic, but are not limited to the above-mentioned division, as long as the corresponding functions can be achieved; in addition, the specific names of the functional units are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of the present invention.

[0131] Note that the above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of the present invention is determined by the scope of the appended claims. Industrial Applicability

[0132] Through the above description of the embodiments, those skilled in the art will clearly understand that the present application can be implemented using software and necessary general-purpose hardware. Of course, it can also be implemented using hardware, but in many cases the former is the preferred embodiment. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored on a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory (FLASH), hard disk, or optical disk, and includes instructions for enabling a computer device (which can be a personal computer, server, or grid device, etc.) to execute the methods described in various embodiments of the present invention. Sequence Listing Free Content

[0133] This application does not involve a sequence listing.

Claims

1. A ranging value NLOS identification method, characterized in that, Including: Obtaining the channel impulse response (CIR) of the channel corresponding to the ranging value; Calculating the first path position index and the strongest path position index based on the CIR; Obtaining the first NLOS state value of the ranging value according to the first path position index, the strongest path position index, and a preset NLOS state level; Obtaining at least two NLOS level correction parameters of the ranging value, and successively correcting the NLOS state value of the ranging value according to the at least two NLOS level correction parameters to obtain the final NLOS state value of the ranging value; wherein, the at least two NLOS level correction parameters are selected from the following correction parameters: the first path power and the received power corresponding to the ranging value, the motion speed information of the ranging target corresponding to the ranging value, the reference benchmark of the NLOS level of the ranging value, and the information of the ranging value and the sides of the corresponding triangle.

2. The method according to claim 1, wherein, The obtaining the first NLOS state value of the ranging value according to the first path position index, the strongest path position index, and a preset NLOS state level includes: Obtaining the first NLOS state value of the ranging value according to the difference between the first path position index and the strongest path position index and the preset NLOS state level.

3. The method according to claim 2, wherein The state value of the preset NLOS state level is state = 0, 1, 2, 3; wherein, 0, 1, 2, 3 respectively represent that the channel scenario of the ranging value is a line-of-sight environment LOS, very likely to be LOS, very likely to be NLOS, or NLOS; The obtaining the first NLOS state value of the ranging value according to the difference between the first path position index and the strongest path position index and the preset NLOS state level includes: If the ranging value is obtained based on two-way ranging, and the index differences between the first path position index and the strongest path position index of the three ranging packets of the ranging value are all less than the index difference threshold, then the state of the ranging value is 0; if the index differences between the first path position index and the strongest path position index of one or two of the three ranging packets are less than the index difference threshold, then the state of the ranging value is 1; if the index differences between the first path position index and the strongest path position index of the three ranging packets of the ranging value are all greater than or equal to the index difference threshold, then the state of the ranging value is 2.

4. The method according to claim 1, wherein, The successively correcting the NLOS state value of the ranging value according to the at least two NLOS level correction parameters to obtain the final NLOS state value of the ranging value includes: When the NLOS level correction parameter is the first path power and the received power corresponding to the ranging value, correcting the NLOS state value of the ranging value according to the difference between the first path power and the received power of the ranging value.

5. The method according to claim 4, wherein, The state value of the preset NLOS state level is state = 0, 1, 2, 3; wherein, 0, 1, 2, 3 respectively represent that the channel scenario of the ranging value is a line-of-sight environment LOS, very likely to be LOS, very likely to be NLOS, or NLOS; The correcting the NLOS state value of the ranging value according to the difference between the first path power and the received power of the ranging value includes: If the ranging value is obtained based on two-way ranging, before this correction, the state of the ranging value is 2, and the difference between the leading diameter power and the received power of the three ranging packets of the ranging value is less than the difference threshold corresponding to the received power of each packet, then the state of the corrected ranging value is 1. If the difference between the leading diameter power and the received power of the three ranging packets of the ranging value is greater than or equal to the difference threshold corresponding to the received power of each packet, then the state of the ranging value is 2.

6. The method according to claim 1, wherein, The method of successively correcting the NLOS state value of the ranging value according to the at least two NLOS level correction parameters and obtaining the final NLOS state value of the ranging value includes: When the NLOS level correction parameter is the motion speed information of the ranging target corresponding to the ranging value, the maximum distance difference threshold between adjacent ranging values is obtained according to the ranging frequency and the maximum motion speed of the ranging target, and the NLOS state value of the ranging value is corrected according to the maximum distance difference threshold.

7. The method according to claim 6, wherein The state value state of the preset NLOS state level is 0, 1, 2, 3; where 0, 1, 2, 3 respectively represent that the channel scenario of the ranging value is line-of-sight environment LOS, very likely to be LOS, very likely to be NLOS or NLOS; The method of correcting the NLOS state value of the ranging value according to the maximum distance difference threshold includes: If d_now - d_before > , then state_now = 3; If state_now = 2 && d_now < d_before + / 4 && state_before <= 1, then state_now = 1; If state_before = 3 && d_now > d_before, state_now = 3; Among them, d_now is the current ranging value, and d_before is the ranging value of the previous round; state_now is the NLOS status value of the current ranging value, and state_before is the NLOS status value of the previous round of ranging value. is the maximum distance difference threshold between adjacent ranging values.

8. The method according to claim 1, wherein The method of successively correcting the NLOS state value of the ranging value according to the at least two NLOS level correction parameters and obtaining the final NLOS state value of the ranging value includes: When the NLOS level correction parameter is the reference benchmark of the NLOS level of the ranging value, a reference benchmark of the NLOS level of the ranging value is established, and the NLOS state value of the ranging value is corrected according to the average value and / or standard deviation of the n ranging values in the reference benchmark; where the reference benchmark includes n consecutive ranging values that meet the preset conditions; n is a natural number greater than 1.

9. The method according to claim 8, wherein, The state value state of the preset NLOS state level is 0, 1, 2, 3; where 0, 1, 2, 3 respectively represent that the channel scenario of the ranging value is line-of-sight environment LOS, very likely to be LOS, very likely to be NLOS or NLOS; The method of correcting the NLOS state value of the ranging value according to the average value and standard deviation of the n ranging values in the reference benchmark includes: If the state of the n ranging values is 0 or 1, when the state_now of the (n + 1)-th ranging value is 2, calculate the average value value_mean and standard deviation value_std of the 2nd to (n + 1)-th ranging values; If abs(d_now - value_mean) < threshold_mean && value_std < threshold_std, then state_now of the ranging value after this correction is 1; where threshold_mean represents the threshold of the difference between the average ranging value and the current ranging value within the reference benchmark window, and threshold_std represents the threshold of the standard deviation of n ranging values within the reference benchmark window; where both threshold_mean and threshold_std = g(f, v, n) are related to the ranging frequency, the speed of the ranging target, and the value of n.

10. The method according to claim 1, wherein, Successively correcting the NLOS status value of the ranging value according to the at least two NLOS level correction parameters and obtaining the final NLOS status value of the ranging value includes: When the NLOS level correction parameter is the information of the ranging value and the sides of the corresponding triangle, correcting the NLOS status value of the ranging value according to the information of the ranging value and the sides of the corresponding triangle and the relationship between the three sides of the triangle.

11. The method according to claim 10, wherein, The status values state of the preset NLOS status levels are 0, 1, 2, 3; where 0, 1, 2, 3 respectively represent that the channel scenario of the ranging value is line-of-sight environment LOS, very likely to be LOS, very likely to be NLOS, or NLOS; Correcting the NLOS status value of the ranging value according to the information of the ranging value and the sides of the corresponding triangle and the relationship between the three sides of the triangle includes: If the ranging value , ranging value are the distances between the ranging target and the first base station and the second base station, respectively, and With The absolute value of the difference is greater than the distance between the first base station and the second base station. If , then the ranging value The state = 3, if , then the ranging value with state = 3.

12. The method according to claim 1, wherein, Successively correcting the NLOS status value of the ranging value according to the at least two NLOS level correction parameters and obtaining the final NLOS status value of the ranging value includes: Performing corrections successively in the following order: the first path power and received power corresponding to the ranging value, the motion speed information of the ranging target corresponding to the ranging value, the reference benchmark of the NLOS level of the ranging value, and the information of the ranging value and the sides of the corresponding triangle.

13. The method according to claim 1, wherein The method further includes: Performing TOA or TDOA positioning based on the final NLOS status value of the ranging value.

14. A ranging value NLOS recognition device, characterized in that including: A CIR acquisition module for acquiring the channel impulse response CIR of the channel corresponding to the ranging value; A position calculation module for calculating the first path position index and the strongest path position index according to the CIR; A first identification module for obtaining the first NLOS status value of the ranging value according to the first path position index, the strongest path position index, and the preset NLOS status level; and A correction module, configured to obtain at least two NLOS level correction parameters of the ranging value, and successively correct the NLOS status value of the ranging value according to the at least two NLOS level correction parameters to obtain the final NLOS status value of the ranging value; wherein, the at least two NLOS level correction parameters are selected from the following correction parameters: the first path power and the received power corresponding to the ranging value, the moving speed information of the ranging target corresponding to the ranging value, the reference benchmark of the NLOS level of the ranging value, and the information of the ranging value and the sides of the corresponding triangle.

15. A receiving device, characterized in that, It includes a memory, a transceiver, and a processor; The memory is used for storing computer programs; The transceiver is used for transceiving data under the control of the processor; the processor is used for reading the computer program in the memory and implementing the ranging value NLOS recognition method according to any one of claims 1-13 when executing the program.

16. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the ranging value NLOS recognition method according to any one of claims 1-13.

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