Wireless positioning method, device, equipment and storage medium

Abstract

The present application discloses a wireless positioning method, device, equipment and storage medium, which relates to the field of wireless communications, including: based on multiple transmission processes of positioning reference signals between a user terminal to be positioned and multiple base stations synchronized in time and frequency, calculating the CFR quotients of multiple preset base station pairs, eliminating the time delay and phase jitter errors of multiple transmission processes; compensating for the phase offset caused by the terminal movement according to the parameter value of the pre-set non-zero-order motion parameter, which helps to achieve the phase alignment of the CFR quotients at different times, and then performing coherent accumulation, estimating the motion parameters of the user terminal relative to the base station pair according to the CSI quotient after coherent accumulation. The present application improves the signal-to-noise ratio through coherent accumulation, and improves the observation accuracy of the relative motion parameters of the terminal to the two base stations; finally, based on the position of each base station and the observed value of the motion parameters of the terminal relative to each preset base station pair, the user terminal is positioned, which improves the terminal positioning accuracy to a certain extent.

Description

Technical Field

[0001] The present application relates to the field of wireless positioning technology, and in particular to a wireless positioning method, device, equipment and storage medium. Background Art

[0002] Wireless positioning refers to a positioning solution implemented using radio signals, which can specifically include: determining positioning parameters such as the signal arrival time (TOA), signal arrival angle or signal departure angle that characterize the relative position relationship between the transmitter and the receiver based on the radio signal transmission between the transmitter and the receiver, and on this basis, combining the terminal positions that have been determined in the transmitter and the receiver to locate another terminal.

[0003] The current wireless positioning solutions have the problem of inaccurate positioning parameter estimation, making it difficult to achieve high-precision positioning tasks. Summary of the invention

[0004] In view of the above problems, the present application provides a wireless positioning method, apparatus, device and storage medium to improve the estimation accuracy of positioning parameters, thereby improving the wireless positioning accuracy.

[0005] The specific plan is as follows:

[0006] The first aspect of the present application provides a wireless positioning method, comprising:

[0007] Based on Q transmission processes of positioning reference signals between the user terminal to be located and M base stations synchronized in time and frequency, calculating the channel frequency response CFR quotients of M' preset base station pairs; any preset base station pair is composed of 2 base stations among the M base stations, and both Q and M' are integers greater than 1;

[0008] Extracting multiple parameter values ​​of non-zero-order motion parameters from a preset range of motion parameter values, and performing motion compensation on each CFR quotient according to the extracted parameter values; wherein the motion compensation value used when compensating any CFR quotient according to any parameter value is calculated by the parameter value and is used to compensate for the difference between the CFR quotient caused by the motion of the user terminal and the target CFR quotient, and the target CFR quotient corresponds to a target transmission process pre-specified in the Q transmission processes;

[0009] Coherently accumulate the compensated CFR quotients obtained according to the same parameter value compensation and corresponding to the same preset base station pair and subcarrier to obtain the coherently accumulated CFR quotients; group the coherently accumulated CFR quotients corresponding to the same preset base station pair and parameter value into one group to obtain the coherently accumulated channel state information CSI quotients;

[0010] Calculate the spectrum value of each CSI quotient after coherent accumulation respectively; the value of the spectrum value is positively correlated with the matching degree, and the matching degree is the matching degree between the parameter value of the non-zero-order motion parameter corresponding to the spectrum value and the actual motion parameter value;

[0011] For any base station pair among the M' preset base station pairs, find the maximum spectrum value from the calculated spectrum values ​​of the base station pair, perform motion parameter estimation according to the CSI quotient after coherent accumulation corresponding to the maximum spectrum value, and obtain the motion parameter observation value of the base station pair, the motion parameter observation value of the base station pair including: the observation value of the distance difference between the user terminal and the two base stations constituting the base station pair at the signal transmission time of the target transmission process;

[0012] The user terminal is positioned according to the positions of the M base stations and the observed values ​​of the motion parameters of the M' preset base station pairs.

[0013] A second aspect of the present application provides a wireless positioning device, comprising:

[0014] A CFR quotient calculation unit is used to calculate the channel frequency response CFR quotients of M' preset base station pairs based on Q transmission processes of the positioning reference signal between the user terminal to be located and the M base stations synchronized in time and frequency; any preset base station pair is composed of 2 base stations among the M base stations, and the Q and the M' are both integers greater than 1;

[0015] a motion compensation unit, configured to extract a plurality of parameter values ​​of non-zero-order motion parameters from a preset motion parameter value range, and perform motion compensation on each CFR quotient according to the extracted parameter values; wherein the motion compensation value used when compensating any CFR quotient according to any parameter value is calculated from the parameter value and is used to compensate for the difference between the CFR quotient caused by the motion of the user terminal and the target CFR quotient, the target CFR quotient corresponding to the target transmission process pre-specified in the Q transmission processes;

[0016] The motion compensation unit is also used to coherently accumulate the compensated CFR quotients obtained according to the same parameter value compensation and corresponding to the same preset base station pair and subcarrier to obtain the coherently accumulated CFR quotients; group the coherently accumulated CFR quotients corresponding to the same preset base station pair and parameter value to obtain the coherently accumulated channel state information CSI quotients; respectively calculate the spectrum values ​​of each coherently accumulated CSI quotient; the numerical value of the spectrum value is positively correlated with the matching degree, and the matching degree is the matching degree between the parameter value of the non-zero-order motion parameter corresponding to the spectrum value and the actual motion parameter value; for any base station pair among the M' preset base station pairs, find the maximum spectrum value from the calculated spectrum values ​​of the base station pair, estimate the motion parameters according to the coherently accumulated CSI quotient corresponding to the maximum spectrum value, and obtain the motion parameter observation value of the base station pair, the motion parameter observation value of the base station pair includes: the observation value of the distance difference between the user terminal and the two base stations constituting the base station pair at the signal transmission moment of the target transmission process;

[0017] A positioning unit is used to position the user terminal according to the positions of the M base stations and the observed values ​​of the motion parameters of the M' preset base station pairs.

[0018] A third aspect of the present application provides a wireless positioning device, comprising at least one processor and a memory connected to the processor, wherein:

[0019] The memory is used to store computer programs;

[0020] The processor is used to execute the computer program to implement the wireless positioning method described in the first aspect above.

[0021] A fourth aspect of the present application provides a storage medium, which carries one or more computer programs. When the one or more computer programs are executed by an electronic device, the electronic device can perform the wireless positioning method described in the first aspect.

[0022] By means of the above technical scheme, the present application locates the user terminal according to the transmission of multiple positioning reference signals between the wireless communication base station with accurately known position and time-frequency synchronization and the user terminal to be located. Specifically, firstly, based on the multiple transmission processes of the positioning reference signals between the user terminal to be located and multiple base stations with time-frequency synchronization, the CFR quotients of multiple preset base station pairs are calculated to eliminate the delay jitter and phase jitter between the base station and the user terminal; then, the CFR quotient is motion compensated according to the parameter value of the pre-set non-zero-order motion parameter, and the compensated CFR quotient of the same base station pair on the same subcarrier obtained by the parameter value compensation of the same non-zero-order motion parameter is coherently accumulated to obtain the CSI quotient after coherent accumulation, and the motion parameters of the user terminal relative to each base station pair are estimated according to the CSI quotient after coherent accumulation of each base station pair, and the motion parameter observation value that matches the actual situation and can eliminate the difference in CFR quotients of different transmission processes caused by the motion of the user terminal to a certain extent is determined by the spectrum value of the CSI quotient after coherent accumulation that is positively correlated with the matching degree.

[0023] The present application first eliminates the time-frequency synchronization error between the base station and the user terminal, and then considers the movement of the user terminal during multiple signal transmissions, compensates for the phase offset caused by the movement of the user terminal, and realizes the phase alignment and superposition of channel information within a period of time. The present application can be applicable to scenarios where the user terminal moves rapidly, without limiting the position of the user terminal to be the same during multiple signal transmissions. The present application improves the signal-to-noise ratio through motion compensation and coherent accumulation, and improves the accuracy of the channel information used for observing the motion of the user terminal, so that base stations that are farther away from the user terminal and base stations with lower transmission power can also provide data support for observing the motion parameters of the user terminal, providing a basis for enriching the data basis for terminal motion estimation, and ultimately improving the observation accuracy of the distance difference between the user terminal and the two base stations; based on this, the user terminal is positioned according to the position of each base station and the motion parameter observation values ​​of each base station pair, which improves the accuracy of terminal positioning to a certain extent, and realizes the positioning enhancement task for the moving terminal in the wireless positioning system. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0025] Figure 1 An example of a wireless positioning scenario diagram of a user terminal is provided;

[0026] Figure 2A flowchart of a wireless positioning method provided by this application;

[0027] Figure 3 An example of a wireless positioning scenario diagram is shown;

[0028] Figure 4 A schematic diagram of the distance-velocity spectrum when no motion compensation is performed is shown;

[0029] Figure 5 A schematic cross-sectional view of the distance-velocity dimension after motion compensation is shown;

[0030] Figure 6 A schematic cross-sectional view of the distance-acceleration dimension after motion compensation is shown;

[0031] Figure 7 The error diagram of motion parameter estimation is illustrated;

[0032] Figure 8 An example of the statistical diagram of the estimation error ECDF of motion parameter estimation is shown;

[0033] Fig. 9 A schematic diagram of the structure of a wireless positioning device provided in this application;

[0034] Fig.10 A schematic diagram of the structure of a wireless positioning device provided in this application. DETAILED DESCRIPTION

[0035] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application. The terms used in the implementation mode of the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application. It is known to those skilled in the art that with the development of technology and the emergence of new scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0036] First, according to the different signal transmission directions, wireless positioning can include uplink wireless positioning and downlink wireless positioning. For uplink wireless positioning, the transmitter of the radio signal is the user terminal to be positioned (referred to as the terminal for short), and the base station receives the radio signal as the receiving end and measures the positioning parameters accordingly to obtain the positioning parameter measurement results used to realize the user terminal position estimation and tracking; for downlink wireless positioning, the transmitter of the radio signal is the base station, and the user terminal to be positioned receives the radio signal as the receiving end and measures the positioning parameters accordingly to obtain the positioning parameter measurement results for realizing the terminal positioning task. That is to say, in the wireless positioning system, the base station and the user terminal serve as the transmitter and receiver of the radio signal. In different positioning scenarios, the transmitter can be the base station or the user terminal. In addition, since the product of the arrival time TOA (also called delay) as the positioning parameter and the speed of light is equal to the radio signal propagation distance, the delay measured by the receiving end is equivalent to the distance measurement.

[0037] On this basis, the applicant of this case discovered through research that base stations and user terminals are often equipped with independent local oscillators, that is, base stations and user terminals have independent time and frequency references, which are usually not synchronized. The receiving end of the positioning reference signal cannot determine the accurate propagation delay of the signal in free space by measuring the arrival time of a single signal. Since different signal transmission processes will have different delays or phase jitters, the phases of multiple measurements are not coherent, and the receiving end cannot perform coherent fusion of multiple measurements to eliminate the time-frequency synchronization error, that is, the receiving end cannot determine the accurate radio signal propagation distance, that is, the accurate distance between the base station and the user terminal.

[0038] In order to solve the positioning accuracy problem caused by time-frequency asynchrony, the applicant in this case discovered that it is possible to utilize the high-precision synchronization characteristics between multiple base stations and determine the arrival time difference (TDOA) by the difference in arrival time TOA measured between base stations, thereby improving the measurement accuracy of the distance difference and providing a basis for achieving high-precision terminal positioning tasks.

[0039] Take uplink wireless positioning as an example. Figure 1 A schematic diagram of a wireless positioning scenario of a user terminal is shown, combined with Figure 1As shown in the figure, there are M base stations in the area where the user terminal is located, which are represented as base station 1, base station 2, ..., base station M-1 and base station M. These M base stations have achieved time and frequency synchronization through a high-precision synchronization network. When performing wireless positioning, the user terminal sends positioning reference signals to M base stations, and the base stations receive the positioning reference signals. Then, the baseband processing unit (BBU) of the base station processes the original IQ data (I represents the in-phase component, and Q represents the orthogonal quadrature component) to determine the channel state information (CSI); on this basis, the positioning processor estimates the arrival time (also known as measurement) based on the channel state information of each base station, and then sets the reference base station, and performs differential processing on the arrival time of the remaining base stations and the arrival time of the reference base station to obtain the arrival time difference, and thus realizes the terminal positioning.

[0040] However, the applicant of this case further discovered that in a complex multipath environment, since the signal transmitted by the transmitter will not only reach the receiver through a straight path (i.e., line-of-sight path), but also through multiple non-straight paths such as reflection, the signal received by the receiver is a signal obtained by superimposing multiple signals with different phases and amplitudes. In other words, the delay measured by the receiver includes components related to non-straight paths. In addition, the transmission power of micro base stations, pico base stations, etc. deployed in user terminals, cities or indoor scenes is often small. When the distance between the user terminal and the base station is large, the arrival power of the positioning reference signal transmitted by the transmitter is small, resulting in less signal information available for positioning. Based on this, limited by interference and signal-to-noise ratio, the positioning parameters measured by the receiver based on a single received positioning signal are not accurate, resulting in poor positioning accuracy. In addition, during multiple measurements, the user terminal is more likely to move, and the distance and speed of the user terminal relative to the base station at each moment may be different, that is, there is distance and Doppler frequency migration, and it is impossible to directly perform joint processing on multiple measurement information to improve the signal-to-noise ratio.

[0041] To solve the above problems, the present application provides a wireless positioning method, apparatus, device and storage medium, which improves the positioning accuracy of user terminals based on channel state information of multiple signal transmission processes.

[0042] Figure 2 A flowchart of a wireless positioning method provided by this application. Figure 2 As shown, the method may include the following steps:

[0043] Step S101: Calculate channel frequency response CFR quotients of M' preset base station pairs based on Q transmission processes of positioning reference signals between a user terminal to be located and M base stations that are time-frequency synchronized.

[0044] It should be noted that, based on the wireless positioning scheme described in this application, a wireless positioning process involves a total of Q transmission processes between the transmitter and the receiver, where Q is an integer greater than 1, and the Q transmission process is the process in which the transmitter transmits a positioning reference signal of a specified bandwidth to the receiver at Q times; and, one of the transmitter and the receiver involved is the user terminal, and the other is the M base stations, where M is an integer greater than 2, that is, in the scenario of uplink wireless positioning, the transmitter is the user terminal; in the scenario of downlink wireless positioning, the transmitter is the M base stations synchronized in time and frequency; on this basis, the physical channel between a transmitter and a receiver is called a communication link, and each transmission process includes a signal transmission process on M communication links. The signal transmission time of the positioning reference signals on different communication links in the same transmission process is the same, and the M communication links correspond to the M base stations one by one. In addition, the positioning reference signal described in this application is a positioning reference signal of a specified bandwidth.

[0045] Specifically, the above step S101 may include the following steps AB:

[0046] Step A: Acquire a channel state information CSI set of Q transmission processes.

[0047] The CSI set of each transmission process includes: channel state information CSI of M communication links; each channel state information CSI includes channel frequency response (CFR) on K subcarriers.

[0048] Based on the above content, the channel state information of the mth communication link in the qth transmission process can be expressed as: CSI (m) [q] = {H1 (m) [q],…,H K (m) [q]}; where m represents one of the M communication links, m∈{1,2,…,M}; q represents one of the Q transmission processes, q∈{0,…,Q-1}; H k (m) [q] represents the CFR on the k-th subcarrier of the m-th communication link in the q-th transmission process, where k is the subcarrier number, k∈{1,…,K}.

[0049] Step B: Determine M' preset base station pairs, and calculate the CFR quotient of each preset base station pair based on the CSI sets of Q transmission processes.

[0050] Among them, any preset base station pair is composed of 2 base stations among the M base stations. Since the base stations in the wireless positioning system correspond to the communication links one by one, the preset base station pair can also be called a preset link pair. A preset link pair is composed of 2 of the M communication links. Any CFR quotient is the quotient of 2 CFRs that meet the first preset condition, wherein the first preset condition includes: corresponding to the same transmission process and the same subcarrier and the corresponding 2 communication links are the communication links between the 2 base stations constituting 1 preset base station pair and the user terminal, that is, the link pair composed of these 2 communication links is one of the M' preset link pairs. In addition, M' is an integer greater than 1.

[0051] Based on the above content, there are M'×Q×K CFR quotients calculated. Exemplarily, the CFR quotient on the kth subcarrier of the qth transmission process corresponding to the preset base station pair (m1, m2) composed of base stations m1 and m2 can be expressed as: H k (m1) [q] / H k (m2) [q]; Optionally, for unification and simplification, m1<m2 or m1>m2 can be set.

[0052] In a possible implementation, any base station pair among the M′ preset base station pairs may be composed of a reference base station and a non-reference base station.

[0053] The reference base station is a base station set as a reference among the M base stations, and the non-reference base station is a base station not set as a reference among the M base stations. Exemplarily, the base station used as a reference can be set according to the signal quality of the base station, such as setting one or more base stations with the best signal quality as a reference. For unification and simplification, the CFR of the reference base station can be used as the denominator when calculating the CFR quotient of any base station pair later.

[0054] It should be noted that the CFR information H on the kth subcarrier measured by the receiving end of the mth communication link (i.e., the communication link between the user terminal and the mth base station) during the qth transmission process is k (m) [q] as an example, the CFR corresponding to the direct line of sight component obtained based on the multi-subcarrier broadband signal model can be expressed as:

[0055] ;

[0056] In the formula, represents the distance term, , J represents the imaginary unit, represents the frequency of the kth subcarrier, c represents the speed of light, express The straight-line distance between the user terminal and the mth base station at the moment, represents the relative time determined by the signal transmission time of the qth transmission process (i.e., the qth time among Q times), that is, the difference between the signal transmission time of the qth transmission process and the target time, Indicates the random delay jitter in the qth transmission process (i.e., the qth CSI measurement process); represents the Doppler term, , Indicates wavelength; represents the residual phase term, represents the random phase jitter during the qth signal transmission process, represents the initial phase of the mth base station. In the time window corresponding to the Q moments, the distance It is expressed as the sum of the distance value at the target time and the distance change at the current signal transmission time relative to the target time, wherein the target time is the signal transmission time of the target transmission process, the target transmission process is a pre-specified transmission process in the Q transmission processes, and the distance change can be determined based on the motion parameter value (such as speed value) and relative time value of the user terminal; since the quotient of speed and wavelength can be regarded as the Doppler frequency, based on this, the Doppler term can represent the change of the Doppler frequency over time by using the speed value that changes with time, which can be called Doppler spectrum expansion.

[0057] Exemplarily, the target transmission process may be the earliest transmission process among the Q transmission processes, and the target time is the earliest time among the Q times, which may be called the initial time. The distance value at this time may be called the initial distance, which is expressed as In one possible implementation, the distance between the user terminal and the mth base station can be expressed as It contains the non-zero-order motion information of the user terminal. is the first-order motion parameter of the user terminal relative to the mth base station, also known as the radial velocity, is the second-order motion parameter of the user terminal relative to the m-th base station, which is equal to half of the radial acceleration (for simplicity of description, the second-order motion parameter is referred to as acceleration). Represents the user terminal relative to the mth base station The first-order motion parameter; t is the difference between the current moment and the initial moment.

[0058] It should be noted that as the length of the time window increases, the possibility of changes in the non-zero-order motion parameters of the user terminal increases. Based on this, the length of the time period corresponding to the Q moments can be limited to reduce the possibility of changes in the terminal motion parameters, or to ensure that the change amplitude of the terminal motion parameters is small, providing a basis for improving the accuracy of coherent accumulation. On this basis, combined with the fact that the movement speed of the user terminal in urban or indoor scenes is generally not too fast, within the time window corresponding to the Q moments, the above-mentioned motion equation of the user terminal relative to the mth base station can only contain second-order motion information, that is, only consider the speed and acceleration of the user terminal, so as to simplify the calculation and improve the positioning efficiency.

[0059] Based on the above content, since each base station is synchronized in time and frequency, the random jitter (including random phase jitter and random delay jitter) in the CFR on the kth subcarrier measured by the receiving end in the communication link where each base station is located is the same based on the qth transmission process. Based on this, by taking the quotient of the CFR on the same subcarrier in the same signal transmission process corresponding to the two base stations, the items related to random delay jitter and random phase jitter in the channel information can be eliminated. Taking base stations m1 and m2 constituting the preset base station pair as an example, the CFR quotient of base station m1 corresponding to the qth transmission process and the kth subcarrier relative to base station m2 can be expressed as: ;

[0060] in, , .

[0061] Based on the above motion equation, the terms related to distance are split. It can be seen that the phase of the above CFR quotient contains the difference of relative motion parameters of each order. When the target time is the initial time and only the second-order motion is considered, the phase contains the initial distance difference. , speed difference and acceleration difference .

[0062] Since the range term and Doppler term contain the distance that changes with time t and distance , making the conventional coherent integration algorithm unusable.

[0063] Step S102: extract multiple parameter values ​​of non-zero-order motion parameters from a preset motion parameter value range, and perform motion compensation on each CFR quotient according to the extracted parameter values.

[0064] Among them, the motion compensation value used when compensating any CFR quotient according to any parameter value is calculated by the parameter value and is used to compensate for the difference between the CFR quotient and the target CFR quotient caused by the movement of the user terminal; the target CFR quotient and the CFR quotient correspond to the same preset base station pair and subcarrier, and the target CFR quotient corresponds to a target transmission process pre-specified in the Q transmission processes.

[0065] For the motion compensation values ​​calculated by the same parameter values, a K×Q motion compensation matrix can be obtained according to the corresponding signal transmission process and subcarrier arrangement. The matrix includes K×Q motion compensation values, where the element in the kth row and qth column can represent the motion compensation value corresponding to the qth transmission process and the kth subcarrier.

[0066] It should be noted that the CFR quotients of each preset base station pair can be arranged into a K×Q CFR quotient matrix according to the corresponding signal transmission process and subcarriers, and the K×Q CFR quotients of the base station pair can be compensated using motion compensation matrices calculated using different parameter values ​​to obtain N×Q×K compensated CFR quotients of the base station pair; a total of M'×N×Q×K compensated CFR quotients are obtained by step S103, where N represents the number of multiple parameter values ​​of non-zero-order motion parameters.

[0067] In combination with the above-mentioned CFR quotient formula, the parameter value of the non-zero-order motion parameter can be used to offset the non-zero-order relative motion parameter difference involved in the motion equation, that is, the dimension of the non-zero-order motion parameter is consistent with the pre-specified motion order. Optionally, in the case of considering second-order motion, the parameter value of the non-zero-order motion parameter is a two-dimensional array consisting of velocity values ​​and acceleration values. Exemplarily, the process of extracting multiple parameter values ​​of the non-zero-order motion parameter may include: respectively calculating the velocity interval of the expected user terminal according to a preset step size; and acceleration range Rasterize to get the velocity set , and the acceleration set , a set of non-zero-order motion parameters consisting of any velocity and any acceleration is expressed as , i∈{1,…,I}, j∈{1,…,J}, where I×J=N. In the above case, the parameter values ​​of non-zero-order motion parameters are , i∈{1,…,I}, j∈{1,…,J} The corresponding motion compensation matrix can be expressed as , the element in the kth row and qth column can be expressed as: Where, t qIndicates the time difference between the signal transmission time and the target time of the qth transmission process. Optionally, the adjacent signal transmission time, that is, the time difference between each two adjacent time in Q time, is a preset time length, that is, the transmitter periodically transmits the positioning reference signal with a preset time length as a period, and when the target time is the initial time, t q =q△t, △t represents a preset time length; conj[ ] represents finding a conjugate. In a possible implementation, the above motion compensation matrix can be calculated offline and pre-stored in a terminal device (such as a wireless positioning device) that executes the wireless positioning method described in the present application.

[0068] In addition, after the quotient operation, even if the user terminal performs a simple uniform motion, the distance difference reflected in the CFR quotient no longer changes uniformly. The present application proposes a corresponding motion compensation algorithm and implementation method, which can achieve accurate estimation of the relative motion parameters of the terminal.

[0069] Step S103 , coherently accumulate the compensated CFR quotients obtained by compensation according to the same parameter value and corresponding to the same preset base station pair and subcarrier to obtain the coherently accumulated CFR quotients.

[0070] Specifically, the above step S103 may include: coherently accumulating the compensated CFR quotients that meet the second preset condition to obtain the coherently accumulated CFR quotients. The second preset condition includes: corresponding to the same preset base station pair and subcarrier and performing motion compensation according to the same parameter value; through coherent accumulation, N×M'×K coherently accumulated CFR quotients can be obtained. Exemplarily, using the parameter value of the non-zero-order motion parameter The relative channel information after coherent accumulation on the kth subcarrier corresponding to the base station pair (m1, m2) obtained by the corresponding motion compensation value can be expressed as: .

[0071] Step S104: grouping the coherently accumulated CFR quotients corresponding to the same preset base station pair and parameter value into one group to obtain the coherently accumulated channel state information CSI quotients.

[0072] It should be noted that step S104 obtains a total of N×M' coherently accumulated CSI quotients; for any base station pair, the coherently accumulated CSI quotient of the base station pair includes N coherently accumulated CSI quotients obtained by motion compensation based on N parameter values ​​of non-zero-order motion parameters, and each coherently accumulated CSI quotient includes compensated CFR quotients after coherent accumulation on K subcarriers.

[0073] Step S105: Calculate the spectrum values ​​of the CSI quotients after the coherent accumulation respectively, and determine the motion parameter observation values ​​of the M' preset base station pairs based on the spectrum values.

[0074] The value of the spectrum value is positively correlated with the matching degree, and the matching degree is the matching degree between the parameter value of the non-zero-order motion parameter corresponding to the spectrum value and the actual motion parameter value.

[0075] Specifically, determining the motion parameter observation values ​​of the M' preset base station pairs based on the spectrum value may include: for any one of the M' preset base station pairs, performing the following steps CD:

[0076] Step C: searching for the maximum spectrum value from the calculated spectrum values ​​of the base station pair.

[0077] Step D: performing motion parameter estimation based on the CSI quotient after coherent accumulation corresponding to the maximum spectrum value to obtain the motion parameter observation value of the base station pair.

[0078] The motion parameter observation value of the base station pair includes: the observation value of the distance difference between the user terminal and the two base stations constituting the base station pair at the signal transmission time (ie, target time) of the target transmission process.

[0079] It should be noted that, since the degree of matching between the parameter values ​​of different non-zero-order motion parameters and the actual motion parameter values ​​of the terminal is different, the compensation effects of different motion parameters are different. For each base station pair, the spectrum value is calculated based on the CSI quotient after coherent accumulation corresponding to the parameter values ​​of different non-zero-order motion parameters, and the CSI quotient after coherent accumulation that best matches the actual situation can be determined, which is equivalent to the coherent accumulation result of the CSI quotients of Q target transmission processes. In this way, the motion parameter estimation task of the base station pair is achieved, providing a basis for subsequent positioning.

[0080] Based on the above process, the coherent accumulation of the CSI direct line of sight energy of Q measurements is achieved, and the signal-to-noise ratio is improved. , which provides a basis for improving the area range and positioning accuracy of base stations.

[0081] Step S106: Position the user terminal according to the positions of the M base stations and the observed values ​​of the motion parameters of the M' preset base station pairs.

[0082] The above method locates the user terminal based on the transmission of multiple positioning reference signals between the wireless communication base station with a precisely known position and time-frequency synchronization and the user terminal to be located. Specifically, firstly, based on the multiple transmission processes of the positioning reference signals between the user terminal to be located and multiple base stations with time-frequency synchronization, the CFR quotients of multiple preset base station pairs are calculated to eliminate the delay jitter and phase jitter caused by the time-frequency asynchrony between the base station and the user terminal; then, the CFR quotient is motion compensated according to the parameter value of the pre-set non-zero-order motion parameter, and the compensated CFR quotient of the same base station pair on the same subcarrier obtained by the parameter value compensation of the same non-zero-order motion parameter is coherently accumulated to obtain the CSI quotient after coherent accumulation, and the motion parameters of the user terminal relative to each base station pair are estimated based on the coherent accumulated CSI quotient of each base station pair, and the motion parameter observation value that matches the actual situation and can eliminate the CFR quotient difference of different signal transmission processes caused by the motion of the user terminal to a certain extent is determined by using the spectrum value of the coherently accumulated CSI quotient that is positively correlated with the matching degree.

[0083] This embodiment first eliminates the time-frequency synchronization error between the base station and the user terminal, and then considers the movement of the user terminal during multiple signal transmissions, compensates for the phase offset caused by the movement of the user terminal, and realizes the phase alignment and superposition of channel information within a period of time. This embodiment can be applicable to the scenario where the user terminal moves quickly, and there is no need to limit the position of the user terminal to be the same during multiple signal transmissions. This embodiment improves the signal-to-noise ratio through motion compensation and coherent accumulation, and improves the accuracy of the channel information used for observing the motion of the user terminal, so that base stations that are farther away from the user terminal and base stations with lower transmission power can also provide data support for observing the motion parameters of the user terminal, providing a basis for enriching the data basis for terminal motion estimation, and ultimately improving the observation accuracy of the distance difference between the user terminal and the two base stations; based on this, the user terminal is positioned according to the position of each base station and the motion parameter observation value of each base station pair, which improves the accuracy of terminal positioning to a certain extent, and realizes the positioning enhancement task of the moving terminal in the wireless positioning system.

[0084] In scenarios with limited signal bandwidth, optimizing the distance measurement method (or delay estimation method) can only bring limited improvements in wireless positioning performance. This application estimates and compensates for the terminal motion information within a long time window to achieve joint coherent processing of multiple positioning signals, effectively improving the signal-to-noise ratio during motion parameter estimation and improving the accuracy of distance measurement. In addition, the non-line-of-sight components are often different in the channel state information of different transmission processes. This application enhances the line-of-sight component by coherently accumulating the channel information of multiple transmission processes, and reduces the interference of the non-line-of-sight component on the terminal motion parameter estimation, which helps to improve the accuracy of motion parameter estimation.

[0085] In one or more embodiments provided in the present application, in any process of the Q transmission processes, a process of determining a CFR on a communication link formed by the user terminal and any one of the M base stations includes:

[0086] The first step is to perform radio frequency and digital intermediate frequency processing on the positioning reference signal received by the receiving end to obtain a sampling sequence.

[0087] The obtained sampling sequence can be expressed as: , k=1,...,K, K represents the number of subcarriers; in another possible implementation, the number of sampling points contained in the obtained sampling sequence may also be less than K.

[0088] The second step is to perform K-point discrete Fourier transform on the sampling sequence to obtain frequency domain sampling.

[0089] Through discrete Fourier transform, a discrete signal in the time domain can be converted into a discrete signal in the frequency domain. The obtained frequency domain sampling can be expressed as , k=1,...,K.

[0090] The third step is to perform channel estimation based on the frequency domain sampling to determine channel state information CSI, where the CSI includes CFRs on K subcarriers.

[0091] It should be noted that the positioning reference signal transmitted by the transmitter is a signal of a specified bandwidth, such as orthogonal frequency-division multiplexing (OFDM) signals, ultra-wideband (UWB) signals, frequency modulated continuous wave signals, etc., which are widely used in Wi-Fi and cellular mobile communication networks, and are not limited in this application. In addition, according to measurement theory, the resolution of the delay is related to the bandwidth. For example, a bandwidth of 100 MHz corresponds to a delay resolution of 10 nanoseconds and a distance resolution of 3 meters. Based on this, the bandwidth of the positioning reference signal can be specified according to the actual required observation resolution.

[0092] When determining the channel state information, the channel estimation method used may be a least square channel estimation method, a minimum mean square error (MMSE) estimation method, or a linear minimum mean square error (LMMSE) estimation method, etc., and this application does not limit this. For example, assuming that the positioning reference signal sequence transmitted by the transmitter is , k = 1, ..., K, the channel information on each subcarrier can be expressed as , k = 1, ..., K, the obtained channel state information CSI can be expressed as [ H 1 ,..., H K ] .

[0093] In a possible implementation, respectively calculating the spectrum values ​​of the CSI quotients after the coherent accumulation may include:

[0094] Step E: Perform fast Fourier transform (FFT) on each CSI quotient after coherent accumulation to obtain an FFT result.

[0095] Each FFT result includes P elements, where P is the order of the FFT, which can also be called the number of points, that is, the fast Fourier transform FFT performed is a P-point FFT. Exemplarily, the CSI quotient after coherent accumulation corresponding to any preset base station pair and any non-zero-order motion parameter can be expressed as b n ∈C K×1 , n represents the identifier of the parameter value of the corresponding non-zero-order motion parameter, b n After P (P ≥ K) points of fast Fourier transform FFT, P×1 FFT results are obtained. It should be noted that the FFT results corresponding to the CSI quotients after each coherent accumulation can be used as motion parameter spectra, including zero-order motion parameter spectra (i.e., distance dimension spectra) and non-zero-order motion parameter spectra. The distance vector corresponding to the distance dimension spectra is , p represents the coordinate value of the distance dimension; the spectral value of the motion parameter spectrum is related to the motion parameters (including zero-order motion parameters and non-zero-order motion parameters), specifically, it is positively correlated with the matching degree between the parameter value of the corresponding motion parameter and the actual distance value and the non-zero-order motion parameter value.

[0096] Step F: Calculate the modulus value of each element in each FFT result.

[0097] The spectrum value of any coherently accumulated CSI quotient includes: the modulus value of each element of the FFT result corresponding to the coherently accumulated CSI quotient. The spectrum value of a base station pair may include N×P modulus values, and accordingly, the maximum spectrum value is the maximum modulus value among the N×P modulus values ​​of the base station pair.

[0098] On the basis of the above, performing motion parameter estimation according to the CSI quotient after coherent accumulation corresponding to the maximum spectrum value may include:

[0099] The observed value of the distance difference between the user terminal and the two base stations constituting the base station pair at the target time is determined by the coordinate value of the maximum spectrum value in the distance dimension.

[0100] Taking the multiple parameter values ​​of non-zero-order motion parameters including I×J parameter pairs consisting of I velocity values ​​and J acceleration values ​​as an example, for each CSI quotient b after coherent accumulation, (i,j)Perform FFT (Fast Fourier Transform) at point P to obtain the distance-velocity-acceleration spectrum ξ (i,j) ∈C P×1 , we can (i,j) ,i=1,…,I,j=1,…,J are arranged into a three-dimensional tensor Ξ∈C P×I×J , any point (p,v i ,a j ) corresponds to the value of (v i ,a j ) The pth element value in the FFT result of the CSI quotient after coherent accumulation , and then calculate the modulus of the spectrum, the obtained motion parameter observation value can be expressed as: ,in, Represents the coordinate value of the maximum modulus in the distance dimension domain.

[0101] In another possible implementation manner, the spectrum value is a modulus value of a CSI quotient after coherent accumulation.

[0102] Among them, the modulus value of any coherently accumulated CSI quotient is calculated from the modulus value of the coherently accumulated CFR quotient on each subcarrier included. It should be noted that the modulus value of each coherently accumulated CSI quotient can be used as a non-zero-order motion parameter spectrum, and the spectrum value of the non-zero-order motion parameter spectrum is related to the non-zero-order motion parameter. Specifically, the spectrum value of the spectrum is positively correlated with the matching degree between the parameter value of the corresponding non-zero-order motion parameter and the actual motion parameter value.

[0103] On the basis of the above, performing motion parameter estimation according to the CSI quotient after coherent accumulation corresponding to the maximum spectrum value may include:

[0104] Step G: performing fast Fourier transform (FFT) on the CSI quotient after coherent accumulation corresponding to the maximum spectrum value to obtain an FFT result.

[0105] Step H: determine the peak point in the FFT result.

[0106] The above-mentioned fast Fourier transform FFT is a P-point fast Fourier transform, P ≥ K, and the obtained result is a P×1 FFT result. The distance vector corresponding to any position p is .

[0107] Step I: Determine the observed value of the distance difference between the user terminal and the two base stations constituting the base station pair at the target time based on the position of the peak point.

[0108] Specifically, the position of the peak point can be expressed as , the corresponding distance difference observation value can be expressed as .

[0109] Exemplarily, any CSI quotient after coherent accumulation of a base station pair includes: CFR quotient after coherent accumulation of K subcarriers, which can be expressed as b n ∈C K×1 , the calculated modulus value can be expressed as , where n∈{1,...,N}. It should be noted that the modulus value obtained is , n=1,...,N actually corresponds to the non-zero-order motion parameter spectrum. The larger the value of the spectrum, the closer the actual value representing the non-zero-order motion parameter is to the parameter value of the non-zero-order motion parameter at the corresponding position. Based on this, the motion parameter can be determined by finding the maximum value of the modulus value to achieve the motion parameter measurement task for the user terminal.

[0110] The above scheme reduces the amount of calculation when determining motion parameters by cascading observed motion parameters, which helps to improve the efficiency of motion parameter estimation.

[0111] In one or more embodiments provided in the present application, performing motion parameter estimation according to the CSI quotient after coherent accumulation corresponding to the maximum spectrum value may also include:

[0112] The parameter value of the non-zero-order motion parameter corresponding to the CSI quotient after coherent accumulation corresponding to the maximum spectral value is determined as the observed value of the difference in non-zero-order motion parameters of the user terminal at the target time relative to the two base stations constituting the base station pair.

[0113] Based on this, the motion parameter observation value of the base station pair includes: the observation value of the difference of the non-zero-order motion parameters of the user terminal relative to the two base stations constituting the base station pair at the target time, and the observation value of the distance difference of the user terminal relative to the two base stations constituting the base station pair at the target time. Taking the example that the multiple parameter values ​​of the non-zero-order motion parameters include I×J parameter pairs consisting of I velocity values ​​and J acceleration values, the obtained motion parameter observation value can be expressed as: , , ,in, Indicates the coordinate value of the maximum modulus value in each dimensional domain.

[0114] The non-zero-order motion parameters of the present application may include any-order motion parameters such as speed, acceleration, and jerk. Based on the above content, the present embodiment estimates higher-order motion states, such as speed, acceleration, and jerk. That is, the method of the present application can not only obtain the distance difference (TDOA), but also obtain the speed, acceleration or higher-order relative motion parameters of the terminal relative to the two base stations, which provides richer relative motion parameters for terminal positioning and helps to improve positioning accuracy.

[0115] In one or more embodiments provided in the present application, the non-zero-order motion parameter may include velocity and acceleration.

[0116] It should be noted that in scenarios such as indoors, in factories, and underground parking lots, the terminal movement speed is generally slow, and the second-order motion model can achieve better results.

[0117] In one or more embodiments provided in the present application, a TDOA method may be used to locate the user terminal based on the determined observation value of the distance difference.

[0118] Since the present application improves the signal-to-noise ratio during motion parameter estimation through long-term accumulation, thereby improving the estimation performance of TDOA, on this basis, the TDOA hyperbolic positioning method is used for positioning or tracking, thereby improving the positioning performance.

[0119] In one or more embodiments provided in the present application, positioning the user terminal may include the following steps:

[0120] Step J: configuring state variables respectively used to represent motion parameters of each order of the user terminal in space.

[0121] The various order motion parameters include zero-order motion parameters (i.e., distance) and the non-zero-order motion parameters. Taking the non-zero-order motion parameters including velocity and acceleration as an example, the state variables may include: the position coordinates, velocity vector, and acceleration vector of the user terminal in three-dimensional space.

[0122] Step K: constructing a motion equation of the user terminal based on the state variables.

[0123] The motion equation describes the motion law of the user terminal in space. Exemplarily, the motion equation may be a constant velocity model, a constant acceleration model, etc.

[0124] Step L: construct observation equations corresponding to each of the M' preset base station pairs.

[0125] Among them, the observation equation corresponding to any one of the M' preset base station pairs is expressed as follows: at each signal transmission moment, the observed value of the motion parameter of the base station pair is equal to the calculated value of the difference between the motion parameters of the user terminal relative to the two base stations constituting the base station pair, and the calculated value is determined based on the state variable, the motion equation and the positions of the two base stations constituting the base station pair.

[0126] Step M: positioning and continuously tracking the user terminal based on the observation equations corresponding to the M' preset base stations.

[0127] Taking non-zero-order motion parameters including velocity and acceleration as an example, the configured state variables can be expressed as ,in, represents the location coordinates of the user terminal, and the location coordinates of the signal transmission time corresponding to the qth transmission process can be expressed as ; represents the velocity vector of the user terminal. The velocity vector of the signal transmission time corresponding to the qth transmission process can be expressed as ; represents the acceleration vector of the user terminal. The acceleration vector of the signal transmission time corresponding to the qth transmission process can be expressed as Taking the base station pair (m1, m2) as an example, the corresponding observation equation can be expressed as: ; ; .in, , and Respectively represent the distance, radial velocity and radial acceleration of the user terminal relative to the mth base station at the signal transmission time corresponding to the qth transmission process, where m=m1, or m=m2. Optionally, the motion equation is a constant acceleration model. Based on this, we have: ; ; ;in, Represents the vector norm, is the position vector of the mth base station.

[0128] Based on the motion equations and observation equations described above, algorithms such as extended Kalman filtering, unscented Kalman filtering or particle filtering can be used to achieve continuous tracking of the terminal.

[0129] Compared with the traditional TDOA hyperbolic positioning method, the present application can provide non-zero-order relative motion parameter values, such as additional information such as velocity difference and acceleration difference, thereby enhancing the positioning and tracking performance.

[0130] The above text illustrates the positioning scheme provided in the present application using the transmission process from the 0th to the Q-1th time. Subsequently, a sliding window method can be used to repeat the signal transmission process from the 1st to the Qth time, the signal transmission process from the 2nd to the Q+1th time, and so on, in turn to achieve high-precision continuous positioning of the user terminal.

[0131] For example, Figure 3A schematic diagram of a wireless positioning scenario is shown, which is a simulation scenario based on a 5G wireless communication network and using the wireless positioning solution provided in an embodiment of the present application. Figure 3 The position of the user terminal and the base station in the xy coordinate system is shown, and within the time window of 10 seconds (s), the user terminal follows Figure 3 The trajectory shown is a uniform linear motion. The uplink positioning reference signal transmitted by the user terminal can be received by two base stations (base station 1 and base station 2). Base station 1 is located at position (0m, 0m), base station 2 is located at position (30, 0), and the user terminal moves at a speed of 2m / s in space. Within 10s of simulation, the terminal moves from position (5m, 10m) to position (25m, 10m). The specific simulation parameters are shown in Table 1 below.

[0132] Table 1

[0133]

[0134] The signal-to-noise ratio in the above scenario is relatively low. If the conventional motion parameter estimation method based on a single CSI is used, the direct path spectrum peak is easily submerged and difficult to detect. To solve this problem, the wireless positioning solution provided by the present application is used to perform long-term coherent accumulation based on CSI at multiple moments, so as to utilize the cumulative effect to improve the signal-to-noise ratio. Assume that the second-order motion equation is used for modeling, that is, the difference in motion parameters of the user terminal to be estimated relative to the base station pair is the velocity difference and the acceleration difference, and the above-mentioned wireless positioning solution is applied to the transmission process of 100 positioning reference signals within 1s. Taking the channel state information of the 1st to 100th positioning parameter signals as an example, and the target moment is the initial moment, Figure 4 The figure shows a distance-velocity spectrum diagram when base station 1 is used as a reference base station and no motion compensation is performed. Figure 4 The black horizontal and vertical lines in the figure represent the actual values ​​of the corresponding motion parameters. The present application scheme is applied to perform motion compensation on the CFR quotient according to N groups of parameter values ​​consisting of different velocity values ​​and acceleration values, coherent accumulation is performed on the compensated CFR quotient, and a P-point fast Fourier transform is performed on the coherently accumulated CSI quotient consisting of the coherently accumulated CFR quotient to obtain an N×P-dimensional FFT result. The FFT results are reorganized to obtain the distance-velocity dimension and velocity-acceleration dimension results as shown below: Figure 5 and Figure 6 As shown, combined Figure 4-Figure 6 It can be concluded that: for a moving user terminal, when no motion compensation is performed, the accumulated two-dimensional spectrum has an obvious "defocusing" effect, and there are errors in the estimation of distance difference and speed difference. When motion compensation is performed, the obtained multi-dimensional motion state spectrum can effectively focus on the actual value.

[0135] Based on the above assumptions, the motion parameter estimation and wireless positioning are repeated according to the sliding window processing method described in this application, and the estimation errors of the distance difference, speed difference, and acceleration difference during the movement of the user terminal are statistically analyzed. The relative motion parameter estimation error is obtained as follows: Figure 7 As shown in the figure, the empirical cumulative probability distribution function (ECDF) of the estimation error is shown in Figure 8 As shown, combined Figure 7-Figure 8 The wireless positioning solution provided by this application can obtain better observation values ​​of distance difference, velocity difference and acceleration difference, among which the 90% quantiles of the estimated errors of distance difference, velocity difference and acceleration difference are 0.33m, 0.018m / s and 0.015m / s respectively. 2 The above shows a scheme for estimating the motion parameters of a user terminal relative to a single base station pair. Combined with the motion parameter measurements of the user terminal relative to multiple base station pairs, the high-precision positioning and tracking tasks of the terminal can be finally achieved.

[0136] The wireless positioning device provided in the embodiment of the present application is described below. The wireless positioning device described below and the wireless positioning method described above can be referenced to each other.

[0137] Fig. 9 Schematic diagram of the structure of a wireless positioning device disclosed in an embodiment of the present application. Fig. 9 As shown, the device may include:

[0138] A CFR quotient calculation unit 11 is used to calculate the channel frequency response CFR quotients of M' preset base station pairs based on Q transmission processes of the positioning reference signal between the user terminal to be located and M base stations synchronized in time and frequency; any preset base station pair is composed of two base stations among the M base stations, and the Q and M' are both integers greater than 1;

[0139] A motion compensation unit 12 is used to extract multiple parameter values ​​of non-zero-order motion parameters from a preset motion parameter value range, and perform motion compensation on each CFR quotient according to the extracted parameter values; wherein the motion compensation value used when compensating any CFR quotient according to any parameter value is calculated by the parameter value and is used to compensate for the difference between the CFR quotient caused by the motion of the user terminal and the target CFR quotient, and the target CFR quotient corresponds to the target transmission process pre-specified in the Q transmission processes;

[0140] The motion compensation unit 12 is further used to perform coherent accumulation on the compensated CFR quotients obtained according to the same parameter value compensation and corresponding to the same preset base station pair and subcarrier to obtain the coherently accumulated CFR quotients; group the coherently accumulated CFR quotients corresponding to the same preset base station pair and parameter value to obtain the coherently accumulated channel state information CSI quotients; respectively calculate the spectrum values ​​of each coherently accumulated CSI quotient; the numerical value of the spectrum value is positively correlated with the matching degree, and the matching degree is the matching degree between the parameter value of the non-zero-order motion parameter corresponding to the spectrum value and the actual motion parameter value; for any base station pair among the M' preset base station pairs, find the maximum spectrum value from the calculated spectrum values ​​of the base station pair, perform motion parameter estimation based on the coherently accumulated CSI quotient corresponding to the maximum spectrum value, and obtain the motion parameter observation value of the base station pair, the motion parameter observation value of the base station pair includes: the observation value of the distance difference between the user terminal and the two base stations constituting the base station pair at the signal transmission moment of the target transmission process;

[0141] The positioning unit 13 is configured to position the user terminal according to the positions of the M base stations and the observed values ​​of the motion parameters of the M' preset base station pairs.

[0142] In one or more embodiments provided in the present application, the spectrum value is a modulus value of a CSI quotient after coherent accumulation.

[0143] On the basis of the above, the process of the motion compensation unit 12 estimating the motion parameters according to the CSI quotient after coherent accumulation corresponding to the maximum spectrum value may include:

[0144] Perform a fast Fourier transform FFT on the CSI quotient after coherent accumulation corresponding to the maximum spectral value to obtain an FFT result, determine a peak point in the FFT result, and determine an observed value of a distance difference between the user terminal at the target time and the two base stations constituting the base station pair according to the position of the peak point. In one or more embodiments provided in the present application, the process in which the motion compensation unit 12 calculates the spectral values ​​of each coherently accumulated CSI quotient may include:

[0145] Perform fast Fourier transform FFT on each coherently accumulated CSI quotient to obtain an FFT result, where each FFT result includes P elements, where P is the order of the FFT; calculate the modulus value of each element in each FFT result, and the spectral value of any coherently accumulated CSI quotient includes: the modulus value of each element of the FFT result corresponding to the coherently accumulated CSI quotient.

[0146] On the basis of the above, the process of the motion compensation unit 12 estimating the motion parameters according to the CSI quotient after coherent accumulation corresponding to the maximum spectrum value may include:

[0147] The observed value of the distance difference between the user terminal and the two base stations constituting the base station pair at the target time is determined by the coordinate value of the maximum spectrum value in the distance dimension.

[0148] In one or more embodiments provided in the present application, the process of the motion compensation unit 12 estimating the motion parameter according to the CSI quotient after coherent accumulation corresponding to the maximum spectral value may also include:

[0149] The parameter value of the non-zero-order motion parameter corresponding to the CSI quotient after coherent accumulation corresponding to the maximum spectral value is determined as the observed value of the difference in non-zero-order motion parameters of the user terminal at the target time relative to the two base stations constituting the base station pair; the motion parameter observation value of the base station pair includes: the observed value of the difference in non-zero-order motion parameters of the user terminal at the target time relative to the two base stations constituting the base station pair, and the observed value of the distance difference between the user terminal at the target time and the two base stations constituting the base station pair.

[0150] In one or more embodiments provided in the present application, the non-zero-order motion parameters include velocity and acceleration.

[0151] In one or more embodiments provided in the present application, the process of the positioning unit 13 positioning the user terminal may include:

[0152] configuring state variables respectively used to represent various order motion parameters of the user terminal in space; the various order motion parameters include zero order motion parameters and the non-zero order motion parameters;

[0153] Constructing a motion equation of the user terminal based on the state variable;

[0154] Constructing observation equations corresponding to each of the M' preset base station pairs; the observation equation corresponding to any one of the M' preset base station pairs is expressed as follows: at each signal transmission moment, the observed value of the motion parameter of the base station pair is equal to the calculated value of the difference between the motion parameters of the user terminal relative to the two base stations constituting the base station pair, and the calculated value is determined according to the state variable, the motion equation and the positions of the two base stations constituting the base station pair;

[0155] Based on the observation equations corresponding to the M' preset base station pairs, the user terminal is positioned and continuously tracked.

[0156] In one or more embodiments provided in the present application, in any process of the Q transmission processes, a process of determining a CFR on a communication link formed by the user terminal and any one of the M base stations includes:

[0157] Perform radio frequency and digital intermediate frequency processing on the positioning reference signal received by the receiving end to obtain a sampling sequence;

[0158] Performing a K-point discrete Fourier transform on the sampling sequence to obtain frequency domain sampling;

[0159] Channel estimation is performed based on the frequency domain sampling to determine channel state information CSI, where the CSI includes CFRs on K subcarriers.

[0160] The wireless positioning device provided in the embodiment of the present application can be applied to wireless positioning equipment, such as a terminal with data processing capability: a server, a PC, etc. Optionally, Fig.10 The hardware structure diagram of the wireless positioning device is shown in FIG. Fig.10 , the hardware structure of the wireless positioning device may include: at least one processor 1, at least one communication interface 2, at least one memory 3 and at least one communication bus 4;

[0161] In the embodiment of the present application, the number of the processor 1, the communication interface 2, the memory 3, and the communication bus 4 is at least one, and the processor 1, the communication interface 2, and the memory 3 communicate with each other through the communication bus 4;

[0162] The processor 1 may be a central processing unit CPU, or an application-specific integrated circuit ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of the present invention, etc.;

[0163] The memory 3 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), etc., such as at least one disk memory;

[0164] The memory is used to store computer programs, and the processor is used to execute the computer programs, so that the wireless positioning device can implement any of the above-mentioned wireless positioning methods.

[0165] A storage medium is also provided in an embodiment of the present application. The storage medium carries one or more computer programs. When the one or more computer programs are executed by an electronic device, the electronic device can implement any wireless positioning method provided in the embodiment of the present application.

[0166] An embodiment of the present application also provides a computer program product including computer-readable instructions. When the computer-readable instructions are executed on an electronic device, the electronic device implements any one of the wireless positioning methods provided in the embodiments of the present application.

[0167] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity from another entity, and do not necessarily require or imply any such actual relationship or order between these entities. Moreover, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprises a..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0168] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can refer to each other.

[0169] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A wireless positioning method, characterized in that: include: Based on Q transmission processes of positioning reference signals between the user terminal to be located and M base stations synchronized in time and frequency, calculating the channel frequency response CFR quotients of M' preset base station pairs; any preset base station pair is composed of 2 base stations among the M base stations, and both Q and M' are integers greater than 1; Extracting multiple parameter values ​​of non-zero-order motion parameters from a preset range of motion parameter values, and performing motion compensation on each CFR quotient according to the extracted parameter values; wherein the motion compensation value used when compensating any CFR quotient according to any parameter value is calculated by the parameter value and is used to compensate for the difference between the CFR quotient caused by the motion of the user terminal and the target CFR quotient, and the target CFR quotient corresponds to a target transmission process pre-specified in the Q transmission processes; Coherently accumulate the compensated CFR quotients obtained according to the same parameter value compensation and corresponding to the same preset base station pair and subcarrier to obtain the coherently accumulated CFR quotients; group the coherently accumulated CFR quotients corresponding to the same preset base station pair and parameter value into one group to obtain the coherently accumulated channel state information CSI quotients; Calculate the spectrum value of each CSI quotient after coherent accumulation respectively; the value of the spectrum value is positively correlated with the matching degree, and the matching degree is the matching degree between the parameter value of the non-zero-order motion parameter corresponding to the spectrum value and the actual motion parameter value; For any one of the M' preset base station pairs, find the maximum spectrum value from the calculated spectrum values ​​of the base station pair, perform motion parameter estimation based on the CSI quotient after coherent accumulation corresponding to the maximum spectrum value, and obtain the motion parameter observation value of the base station pair, the motion parameter observation value of the base station pair includes: the observation value of the distance difference between the user terminal and the two base stations constituting the base station pair at the signal transmission time of the target transmission process; the signal transmission time of the target transmission process is the target time; The user terminal is positioned according to the positions of the M base stations and the observed values ​​of the motion parameters of the M' preset base station pairs.

2. The wireless positioning method according to claim 1, characterized in that: The spectrum value is the modulus value of the CSI quotient after coherent accumulation; Motion parameter estimation is performed according to the CSI quotient after coherent accumulation corresponding to the maximum spectrum value, including: Perform fast Fourier transform FFT on the CSI quotient after coherent accumulation corresponding to the maximum spectral value to obtain an FFT result, determine the peak point in the FFT result, and determine the observed value of the distance difference between the user terminal at the target time and the two base stations constituting the base station pair based on the position of the peak point.

3. The wireless positioning method according to claim 1, characterized in that: Calculate the spectrum values ​​of the CSI quotients after each coherent accumulation, including: Performing fast Fourier transform FFT on each coherently accumulated CSI quotient respectively to obtain an FFT result, each FFT result including P elements, where P is the order of the FFT; calculating the modulus value of each element in each FFT result, the spectrum value of any coherently accumulated CSI quotient including: the modulus value of each element of the FFT result corresponding to the coherently accumulated CSI quotient; Motion parameter estimation is performed according to the CSI quotient after coherent accumulation corresponding to the maximum spectrum value, including: The observed value of the distance difference between the user terminal and the two base stations constituting the base station pair at the target time is determined by the coordinate value of the maximum spectrum value in the distance dimension.

4. The wireless positioning method according to any one of claims 1 to 3, characterized in that: Estimating motion parameters according to the CSI quotient after coherent accumulation corresponding to the maximum spectrum value, further comprising: Determine the parameter value of the non-zero-order motion parameter corresponding to the CSI quotient after coherent accumulation corresponding to the maximum spectral value as the observed value of the difference between the non-zero-order motion parameters of the user terminal at the target time relative to the two base stations constituting the base station pair; The motion parameter observation values ​​of the base station pair include: the observation value of the difference in non-zero-order motion parameters of the user terminal relative to the two base stations constituting the base station pair at the target time, and the observation value of the distance difference between the user terminal and the two base stations constituting the base station pair at the target time.

5. The wireless positioning method according to claim 4, characterized in that: The non-zero-order motion parameters include velocity and acceleration.

6. The wireless positioning method according to claim 4, characterized in that: Positioning the user terminal includes: configuring state variables respectively used to represent various order motion parameters of the user terminal in space; the various order motion parameters include zero order motion parameters and the non-zero order motion parameters; Constructing a motion equation of the user terminal based on the state variable; Constructing observation equations corresponding to each of the M' preset base station pairs; the observation equation corresponding to any one of the M' preset base station pairs is expressed as follows: at each signal transmission moment, the observed value of the motion parameter of the base station pair is equal to the calculated value of the difference between the motion parameters of the user terminal relative to the two base stations constituting the base station pair, and the calculated value is determined according to the state variable, the motion equation and the positions of the two base stations constituting the base station pair; Based on the observation equations corresponding to the M' preset base station pairs, the user terminal is positioned and continuously tracked.

7. The wireless positioning method according to any one of claims 1 to 3, characterized in that: In any one of the Q transmission processes, a process of determining a CFR on a communication link formed by the user terminal and any one of the M base stations includes: Perform radio frequency and digital intermediate frequency processing on the positioning reference signal received by the receiving end to obtain a sampling sequence; Performing a K-point discrete Fourier transform on the sampling sequence to obtain frequency domain sampling; Channel estimation is performed based on the frequency domain sampling to determine channel state information CSI, where the CSI includes CFRs on K subcarriers.

8. A wireless positioning device, characterized in that: include: A CFR quotient calculation unit is used to calculate the channel frequency response CFR quotients of M' preset base station pairs based on Q transmission processes of the positioning reference signal between the user terminal to be located and the M base stations synchronized in time and frequency; any preset base station pair is composed of 2 base stations among the M base stations, and the Q and the M' are both integers greater than 1; a motion compensation unit, configured to extract a plurality of parameter values ​​of non-zero-order motion parameters from a preset motion parameter value range, and perform motion compensation on each CFR quotient according to the extracted parameter values; wherein the motion compensation value used when compensating any CFR quotient according to any parameter value is calculated from the parameter value and is used to compensate for the difference between the CFR quotient caused by the motion of the user terminal and the target CFR quotient, the target CFR quotient corresponding to the target transmission process pre-specified in the Q transmission processes; The motion compensation unit is also used to coherently accumulate the compensated CFR quotients obtained according to the same parameter value compensation and corresponding to the same preset base station pair and subcarrier to obtain the coherently accumulated CFR quotients; group the coherently accumulated CFR quotients corresponding to the same preset base station pair and parameter value to obtain the coherently accumulated channel state information CSI quotients; respectively calculate the spectrum values ​​of each coherently accumulated CSI quotient; the numerical value of the spectrum value is positively correlated with the matching degree, and the matching degree is the matching degree between the parameter value of the non-zero-order motion parameter corresponding to the spectrum value and the actual motion parameter value; for any base station pair among the M' preset base station pairs, find the maximum spectrum value from the calculated spectrum values ​​of the base station pair, estimate the motion parameters according to the coherently accumulated CSI quotient corresponding to the maximum spectrum value, and obtain the motion parameter observation value of the base station pair, the motion parameter observation value of the base station pair includes: the observation value of the distance difference between the user terminal and the two base stations constituting the base station pair at the signal transmission time of the target transmission process; the signal transmission time of the target transmission process is the target time; A positioning unit is used to position the user terminal according to the positions of the M base stations and the observed values ​​of the motion parameters of the M' preset base station pairs.

9. A wireless positioning device, characterized in that: The method comprises at least one processor and a memory connected to the processor, wherein: The memory is used to store computer programs; The processor is used to execute the computer program so that the wireless positioning device can implement the wireless positioning method as described in any one of claims 1 to 7.

10. A storage medium, characterized in that: The storage medium carries one or more computer programs, which, when executed by an electronic device, enable the electronic device to implement the wireless positioning method as described in any one of claims 1 to 7.

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