Positioning method, device, equipment, medium and program of backscattering device

Abstract

Embodiments of the present disclosure provide a positioning method and device of a backscattering device, computer device, readable storage medium and program, and relate to the technical field of computer communication. The method comprises: receiving a mixed signal, wherein the mixed signal comprises a direct signal and a reflected signal; obtaining a first incident estimation angle of the direct signal and a second incident estimation angle of the reflected signal; obtaining a direct estimation signal and a reflected estimation signal according to the first incident estimation angle and the second incident estimation angle; obtaining a reflected link delay according to the direct estimation signal and the reflected estimation signal; obtaining a reflected link length according to the reflected link delay; and obtaining coordinates of the backscattering device by an elliptic formula algorithm according to a radio frequency source coordinate, a receiver coordinate, the reflected link length, the first incident estimation angle and the second incident estimation angle. The method provided by the embodiments of the present disclosure can realize positioning of the backscattering device.

Description

Technical Field

[0001] This disclosure relates to the field of computer communication technology, and in particular to a method, apparatus, computer device, readable storage medium, and program for locating a backscattering device. Background Technology

[0002] The emergence of numerous new businesses, such as the Internet of Things (IoT) and the Industrial Internet of Things (IIoT), will pose significant challenges to spectrum usage and energy utilization. Communication and sensing, as two fundamental functions of IoT devices, are highly coupled in information processing. Therefore, integrated sensing and communication technology has become one of the core technologies of sixth-generation mobile communication (6G) to address issues such as spectrum congestion and hardware costs. However, the design and operating mode of backscattering devices are simple, making it impossible to locate them using existing 3GPP (3rd Generation Partnership Project) positioning technologies. Summary of the Invention

[0003] This disclosure provides a method, apparatus, computer device, readable storage medium, and program for locating a backscattering device, relating to the field of computer communication technology, and capable of locating a backscattering device.

[0004] This disclosure provides a method for locating a backscattering device, comprising: receiving a mixed signal, wherein the mixed signal includes a direct signal and a reflected signal; obtaining a first incident estimated angle of the direct signal and a second incident estimated angle of the reflected signal; obtaining a direct estimated signal and a reflected estimated signal based on the first incident estimated angle and the second incident estimated angle; obtaining a reflected link delay based on the direct estimated signal and the reflected estimated signal; obtaining a reflected link length based on the reflected link delay; and obtaining the coordinates of the backscattering device using an elliptic curve algorithm based on the coordinates of the radio frequency source, the coordinates of the receiver, the reflected link length, the first incident estimated angle, and the second incident estimated angle.

[0005] In one embodiment, obtaining the first incident estimated angle of the direct signal and the second incident estimated angle of the reflected signal includes: obtaining the first incident estimated angle of the direct signal and the second incident estimated angle of the reflected signal according to the root-music algorithm.

[0006] In one embodiment, obtaining the direct projection estimation signal and the reflection estimation signal based on the first incident estimation angle and the second incident estimation angle includes: obtaining a first weight vector of the direct projection signal based on the first incident estimation angle; obtaining the direct projection estimation signal of the direct projection signal based on the first weight vector and the mixed signal; obtaining a second weight vector of the reflection signal based on the second incident estimation angle; and obtaining the reflection estimation signal of the reflection signal based on the second weight vector and the mixed signal.

[0007] In one embodiment, obtaining the first weight vector of the direct signal based on the first incident estimation angle includes: obtaining the first weight vector of the direct signal based on the first incident estimation angle using the Lagrange daily number method; obtaining the second weight vector of the reflected signal based on the second incident estimation angle includes: obtaining the second weight vector of the reflected signal based on the second incident estimation angle using the Lagrange daily number method.

[0008] In one embodiment, obtaining the reflection link delay based on the direct projection estimation signal and the reflection estimation signal includes: obtaining the direct projection propagation delay through cyclic prefix autocorrelation based on the direct projection estimation signal; obtaining the reflection propagation delay through cyclic prefix autocorrelation based on the reflection estimation signal; and obtaining the reflection link delay based on the direct projection link delay, the direct projection propagation delay, and the reflection propagation delay.

[0009] In one embodiment, obtaining the coordinates of the backscattering device using an elliptic formula algorithm based on the coordinates of the RF source, the receiver, the length of the reflection link, the first incident estimated angle, and the second incident estimated angle includes: obtaining the coordinates of the ellipse center and the focal length of the ellipse based on the coordinates of the RF source and the receiver; obtaining the semi-major axis of the ellipse based on the length of the reflection link; obtaining the semi-minor axis based on the semi-major axis and the focal length; establishing an elliptic formula based on the center coordinates, the semi-major axis, the semi-minor axis, and the first incident estimated angle; and obtaining the coordinates of the backscattering device based on the slope of the line connecting the backscattering device and the receiver and the elliptic formula.

[0010] This disclosure provides a positioning device for a backscattering device, comprising: a receiving module for receiving a mixed signal, wherein the mixed signal includes a direct signal and a reflected signal; an acquisition module for acquiring a first incident estimated angle of the direct signal and a second incident estimated angle of the reflected signal; the acquisition module is further configured to acquire a direct estimated signal and a reflected estimated signal based on the first incident estimated angle and the second incident estimated angle; the acquisition module is further configured to acquire a reflection link delay based on the direct estimated signal and the reflected estimated signal; the acquisition module is further configured to acquire a reflection link length based on the reflection link delay; and the acquisition module is further configured to acquire the coordinates of the backscattering device using an elliptic formula algorithm based on the coordinates of the radio frequency source, the coordinates of the receiver, the reflection link length, the first incident estimated angle, and the second incident estimated angle.

[0011] This disclosure provides a computer device including a processor, a memory, and an input / output interface. The processor is connected to both the memory and the input / output interface. The input / output interface is used to receive and output data, the memory is used to store computer programs, and the processor is used to invoke the computer programs so that the computer device executes any of the methods described in the above embodiments.

[0012] This disclosure provides a computer-readable storage medium storing a computer program adapted to be loaded and executed by a processor, such that a computer device having a processor performs the method described in any of the above embodiments.

[0013] This disclosure provides a computer program product, including a computer program that is executed by a processor using any of the methods described in the above embodiments.

[0014] The backscattering device positioning method of this application involves receiving a mixed signal, including a direct signal and a reflected signal; obtaining a first incident estimated angle of the direct signal and a second incident estimated angle of the reflected signal; obtaining a direct estimated signal and a reflected estimated signal based on the first and second incident estimated angles; obtaining a reflected link delay based on the direct and reflected estimated signals; obtaining a reflected link length based on the reflected link delay; and obtaining the coordinates of the backscattering device using an elliptic formula algorithm based on the RF source coordinates, receiver coordinates, reflected link length, first incident estimated angle, and second incident estimated angle, thereby enabling the positioning of the backscattering device. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a model diagram of the integrated sensing and communication system based on environmental backscattering proposed in this application.

[0017] Figure 2 A schematic diagram of a non-traditional BPSK modulation transmission according to an embodiment of this disclosure is shown.

[0018] Figure 3 This is a flowchart of a method for locating a backscattering device provided in an embodiment of this disclosure.

[0019] Figure 4 A schematic diagram illustrating the direct link delay, reflected link delay, direct portion propagation delay, and reflected portion propagation delay according to an embodiment of this disclosure is shown.

[0020] Figure 5 A schematic diagram of an elliptic formula algorithm according to an embodiment of the present disclosure is shown.

[0021] Figure 6 This is a schematic diagram of the structure of a positioning device for a backscattering device provided in an embodiment of this disclosure.

[0022] Figure 7 This is a schematic diagram of the structure of a computer device provided in an embodiment of this disclosure. Detailed Implementation

[0023] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0024] In this embodiment of the disclosure, a sensing communication technology based on environmental backscattering can be used to receive mixed signals, wherein the mixed signals include direct signals and reflected signals; a first incident estimation angle of the direct signal and a second incident estimation angle of the reflected signal are obtained; a direct estimation signal and a reflected estimation signal are obtained based on the first incident estimation angle and the second incident estimation angle; a reflected link delay is obtained based on the direct estimation signal and the reflected estimation signal; a reflected link length is obtained based on the reflected link delay; and the coordinates of the backscattering device are obtained using an elliptic formula algorithm based on the coordinates of the radio frequency source, the coordinates of the receiver, the reflected link length, the first incident estimation angle, and the second incident estimation angle, thereby realizing the positioning of the backscattering device.

[0025] The following section will first explain some background technology of this disclosure:

[0026] Figure 1 This is a model diagram of the integrated sensing and communication system based on environmental backscattering proposed in this application.

[0027] like Figure 1 As shown, the system comprises three parts: an ambient radio frequency source 101 (e.g., a base station), a backscattering device 102, and a receiver 103. The backscattering device 102 can be, for example, a single antenna, and the receiver 103 is equipped with an M-element uniform linear array (M antennas). The channel is, for example, a complex Gaussian channel, where f, h, and g represent the channel fading coefficients from the ambient radio frequency source 101 to the receiver 103, from the ambient radio frequency source 101 to the backscattering device 102, and from the backscattering device 102 to the receiver 103, respectively. θ d θ represents the angle of incidence (first angle of incidence) of the direct-link signal (direct signal). b The second incident angle represents the incident angle of the reflected link signal (reflected signal). Both angles are in the range of [-90°, 90°]. If the signal is incident from the left side of the antenna, it can be written as negative, and vice versa.

[0028] For ease of analysis, the discrete model of the signal in the system is discussed below, i.e., it has already undergone down-conversion and sampling.

[0029] s(n) represents the signal from the ambient radio frequency source 101, p is the transmit power, and the radio frequency source signal is, for example, an OFDM (Orthogonal Frequency Division Multiplexing) signal with N subcarriers and N cyclic prefix length. cp Therefore, the period of one OFDM symbol is N+N. cp The antenna impedance switching frequency of the backscattering device 102 is typically much lower than the sampling rate of the ambient signal, let T... b The symbol period of the backscattering device corresponds to K OFDM symbol periods, i.e., T b =K(N+N) cp ).

[0030] Let α represent the reflection coefficient of the antenna of backscattering device 102, |α| < 1, and x(n) represent the information bits modulated onto the ambient signal by backscattering device 102. After modulation, the reflected signal should be the product of the received signal, the antenna's reflection coefficient, and the transmitted information bits.

[0031] Where x(n) depends on the data and modulation waveform transmitted by the backscattering device 102, specifically as follows:

[0032] The backscattering device uses non-traditional BPSK (Binary Phase Shift Keying) modulation to transmit information, and Information represents the data bits that the backscattering device wants to transmit. When the data bit is "1", there is a state transition in the latter half of the K OFDM symbols within a symbol period of the backscattering device, as shown in Equation (1); while when the data bit is "0", all parts of the K OFDM symbols within a symbol period are flipped, as shown in Equation (2). That is:

[0033] When Information = 0

[0034] x(n) = -1, n = 0, 1, ..., K(N+N) cp )-1 (1)

[0035] When Information = 1

[0036]

[0037] Figure 2 A schematic diagram of a non-traditional BPSK modulation transmission according to an embodiment of this disclosure is shown.

[0038] yd (n) represents the signal after channel fading f on the direct link, called the direct link signal, y b (n) represents the signal that has passed through the channel fading h and g on the reflection link, and is called the reflection link signal. The expressions are as follows: Formula (3) and Formula (4) respectively:

[0039]

[0040]

[0041] The direction vector matrix obtained from the incident angle is given by formula (5):

[0042] A=[a(θ d ),a(θ b (5)

[0043] Where a(θ) d ),a(θ b It can be determined by the following formula (6):

[0044]

[0045] In formula (6), D is the spacing between the antennas of receiver 103, λ is the wavelength of the incident signal carrier, m is the antenna number of receiver 103, m=0 is the reference antenna, e is the natural constant, j is the conjugate of the complex number j, T represents transpose, i=d represents the first incident angle, i=b represents the second incident angle, and M represents the number of antennas of receiver 103.

[0046] Let ω m (n), m=0,1,…,M-1 represents the noise present in the signal received by the m-th antenna of receiver 103, ω m They are independent of each other and all obey a law with a mean of 0 and a variance of 0. The noise is a cyclically symmetric complex Gaussian distribution, and the noise on all antennas constitutes a noise vector: ω(n) = [ω0(n), ω1(n), ..., ω M-1 (n)] T .

[0047] Let y m (n), m=0,1,…,M-1 represents the mixed signal received by the m-th antenna, y(n)=[y0(n),y1(n),…,y M-1 (n)] T The mixed signal received by the antenna array is represented by equation (7).

[0048] y(n)=a(θ d )y d (n)+a(θb )y b (n)+ω(n) (7)

[0049] In related technologies, the design and operating mode of backscattering devices are simple, but there is a problem that the backscattering devices cannot be located using existing 3GPP positioning technology.

[0050] Figure 3 This is a flowchart of a method for locating a backscattering device according to an embodiment of this disclosure. The method provided in this embodiment can be executed by any electronic device with computing capabilities (e.g., installed in receiver 103), and this disclosure is not limited thereto.

[0051] like Figure 3 As shown, the method provided in this disclosure embodiment may include the following steps.

[0052] In step S310, a mixed signal is received, wherein the mixed signal includes a direct signal and a reflected signal.

[0053] In this step, the receiver receives a mixed signal, which includes both direct and reflected signals. The mixed signal is, for example, shown in formula (7).

[0054] In step S320, the first incident estimated angle of the direct signal and the second incident estimated angle of the reflected signal are obtained.

[0055] In this step, the receiver can obtain a first estimated angle of incidence of the direct signal and a second estimated angle of incidence of the reflected signal. In one embodiment, the receiver can obtain the first estimated angle of incidence of the direct signal and the second estimated angle of incidence of the reflected signal according to the root-music algorithm.

[0056] The specific steps to obtain it are as follows: Steps 1-6:

[0057] 1. Select an appropriate number of snapshots N, and use time averaging to approximate the correlation matrix R, as shown in formula (8):

[0058]

[0059] Where R is the correlation matrix, y(n) is the received mixed signal, and H represents the conjugate transpose.

[0060] 2. Regarding Eigenvalue decomposition yields M eigenvalues, which are arranged in descending order. The eigenvectors corresponding to the M-2 smallest eigenvalues ​​are then normalized and used as the basis of the noise subspace: e i ,i=2,3,…,M-1. Where M is the number of antennas of the receiver.

[0061] 3. Construct a vector a(z) = [1, z] -1 ,…,z -(M-1) ] T And constructor f i (z) is shown in the following formula (9):

[0062] f i (z)=a H (z)e i =e i,0 +e i,1 z 1 +…+e i,M-1 z (M-1) (9)

[0063] Where z represents a variable, H represents the conjugate transpose, and M is the number of antennas in the receiver.

[0064] 4. Find P i (z)=f i (z)f i H (z), then sum them up to get P Root-MUSIC (z) As in formula (10):

[0065]

[0066] Where H represents the conjugate transpose, and M is the number of antennas in the receiver.

[0067] 5. Let P Root-MUSIC Given z = 0, find 2M pairs of roots symmetric about the unit circle. Remove the roots outside the unit circle, arrange them in descending order of their modulus, and take the first two values ​​of z. i i = 0, 1.

[0068] 6. According to formula (6), Find θ i ,i=0,1. where θ d_hat =θ0, θ b_hat =θ1. θ d_hat Let θ represent the first incident estimated angle. b_hat This represents the second incident estimated angle.

[0069] In step S330, the direct projection estimation signal and the reflection estimation signal are obtained based on the first incident estimation angle and the second incident estimation angle.

[0070] In this step, the receiver acquires a direct-light estimation signal and a reflection estimation signal based on a first incident estimation angle and a second incident estimation angle. In one embodiment, a first weight vector of the direct-light signal is acquired based on the first incident estimation angle; a direct-light estimation signal of the direct-light signal is acquired based on the first weight vector and the mixed signal; a second weight vector of the reflected signal is acquired based on the second incident estimation angle; and a reflection estimation signal of the reflected signal is acquired based on the second weight vector and the mixed signal.

[0071] The method for obtaining S330 in the above steps is as follows: Steps 1-6:

[0072] Using the estimated θ d_hat and θ b_hat Design a weight vector to perform two spatial domain filters on the received mixed signal to extract the direct link signal and the reflected link signal, respectively. There are many spatial domain filtering algorithms; here, we take a spatial domain filtering algorithm based on the maximum likelihood ratio criterion as an example. The specific steps are as follows:

[0073] 1. The array receives the signal according to formula (7).

[0074] y(n)=a(θ d )y d (n)+a(θ b )y b (n)+ω(n) (7)

[0075] The signal to be extracted is y i (n), i = d, b, and the corresponding array antenna direction vectors are a(θ) and b, respectively. i ), i = d, b, the corresponding beamforming weight vector is w i ,i=d,b. Where d and b represent the incident signal from the direct link and the incident signal from the reflected link, respectively.

[0076] 2. The signal obtained after beamforming is: y i_hat (n)=w i H y(n),i=d,b, its average power is given by formula (11):

[0077] P i =w i H E[y(n)y H (n)]w i =w i H R y w i (11)

[0078] Where H is the conjugate transpose and E represents the expected value.

[0079] 3. In order to make the signal after spatial filtering as close as possible to the signal in the desired direction, the basic idea of ​​spatial filtering is to fix the gain of the signal after filtering in the desired direction and minimize the average power of the filtered signal, which is expressed by the following expression (12):

[0080]

[0081] Where min represents the minimum and st represents the condition that is satisfied.

[0082] 4. Solve the above problem using the Lagrange daily number method. The objective function is as follows: (13)

[0083] L(w i ) = w i H R y w i -η[w i H a(θ i )-1] (13)

[0084] Where η represents the Lagrange factor.

[0085] 5. The optimal weight vector is obtained as shown in formula (14):

[0086]

[0087] Where i is d, w d Let w represent the first weight vector, where i is b. b This represents the second weight vector.

[0088] 6. The direct link estimation signal (direct estimation signal) y obtained by spatial filtering d_hat (n) and reflection link estimation signal (reflection estimation signal) y b_hat (n) are respectively shown in formulas (15) and (16):

[0089]

[0090]

[0091] Where, ω d (n) and ω b (n) represents the noise and interference components after filtering.

[0092] In step S340, the reflection link delay is obtained based on the direct projection estimation signal and the reflection estimation signal.

[0093] In this step, the receiver obtains the reflection link delay based on the direct propagation estimate signal and the reflection estimate signal. In one embodiment, the direct propagation delay is obtained by cyclic prefix autocorrelation based on the direct propagation estimate signal; the reflection propagation delay is obtained by cyclic prefix autocorrelation based on the reflection estimate signal; and the reflection link delay is obtained based on the direct link delay, the direct propagation delay, and the reflection propagation delay.

[0094] Figure 4 A schematic diagram illustrating the direct link delay, reflected link delay, direct portion propagation delay, and reflected portion propagation delay according to an embodiment of this disclosure is shown.

[0095] The method for obtaining S340 in the above steps is as follows: Steps 1-4:

[0096] 1. For example Figure 4 As shown, D f D h D g Let f, h, and g represent the propagation delays of channels respectively, and define the direct link delay D. d =D f and reflection link delay D b =D h +D g .

[0097] 2. Ambient radio frequency sources are usually base stations, etc., therefore the receiver can know the location of the ambient radio frequency source, i.e., D. d Given that the receiver reception cannot be synchronized with the ambient radio frequency source signal transmission, i.e., the receiver starts receiving when the OFDM signal has been transmitted but has not yet reached the receiver, the corresponding propagation delay is denoted as D. d_part and D b_part Therefore, the following relation (17) holds:

[0098] D d -D d_part =D b -D b_part (17)

[0099] 3. Direct propagation delay D d_part and the propagation delay D of the reflected part b_part The following expressions (18) and (19) can be estimated using the signals from the direct link and the reflected link, respectively:

[0100]

[0101]

[0102] In formulas (18) and (19), K is the symbol period; i is a variable; k is a variable; n is a variable; d and b represent the incident signal from the direct link and the incident signal from the reflected link, respectively; c[] refers to the discrete-time sequence signal, and a certain value corresponds to a certain sample value, for example, c

[10] is the 10th sample value of the signal; c[] is a number, c*[] is the conjugate complex number in front, and the result is the inner product; the vertical lines on the numerator and denominator represent the modulus; N is the number of subcarriers, N cp This represents the length of the cyclic prefix.

[0103] Where T es_d =K d (N+N cp ) and T es_b =K b (N+N cp ) are estimates of D d_part and D b_part The time window.

[0104] 4. Estimated reflection link propagation delay D b_hat =D d -D d_part +D b_part .

[0105] In step S350, the reflection link length is obtained based on the reflection link delay.

[0106] In this step, the receiver obtains the reflection link length based on the reflection link delay.

[0107] The length of the reflection link is determined according to formula (20):

[0108] d b =c*D b_hat (20)

[0109] Where c is the speed of light, taken as 3 × 10⁻⁶. 8 m / s.

[0110] In step S360, the coordinates of the backscattering device are obtained using the elliptic formula algorithm based on the coordinates of the RF source, the receiver, the reflection link length, the first incident estimation angle, and the second incident estimation angle.

[0111] In this step, the receiver obtains the coordinates of the backscattering device using an elliptic formula algorithm based on the coordinates of the RF source, the receiver coordinates, the reflection link length, the first incident estimation angle, and the second incident estimation angle. In one embodiment, the coordinates of the ellipse center and the focal length are obtained based on the RF source coordinates and the receiver coordinates; the semi-major axis of the ellipse is obtained based on the reflection link length; the semi-minor axis is obtained based on the semi-major axis and the focal length; an elliptic formula is established based on the center coordinates, semi-major axis, semi-minor axis, and the first incident estimation angle; and the coordinates of the backscattering device are obtained based on the slope of the line connecting the backscattering device and the receiver, as well as the elliptic formula.

[0112] Figure 5 A schematic diagram of an elliptic formula algorithm according to an embodiment of the present disclosure is shown.

[0113] The specific steps for obtaining S360 are as follows: Steps 1-6.

[0114] 1. For example Figure 5 As shown, (x RF ,y RF ), (x BD ,y BD ) and (x RX ,y RX ) represent the coordinates of the ambient radio frequency source, the backscattering device, and the receiver, respectively; d f d h and d g Let represent the distances from the ambient RF source to the receiver, from the ambient RF source to the backscattering device, and from the backscattering device to the receiver, respectively; the corresponding direct link length and reflected link length are d and d, respectively. d =d f and d b =d h +d g .

[0115] 2. From the distance formula, we know that, The reflection link delay D was obtained through delay estimation. b_hat Calculate the length of the reflection link: d b =c*D b_hat Where c is the speed of light, taken as 3 × 10⁻⁶. 8 m / s.

[0116] 3. According to the definition of an ellipse, the backscattering device to be located is positioned with the ambient radio frequency source and receiver as foci, and its semi-major axis as d. b It lies on an ellipse of 2 / 2, therefore its coordinates satisfy the following relationship (21):

[0117]

[0118] The center coordinates of the ellipse are (x0, y0), where x0 = (x0, y0). RF+x RX ) / 2, y0=(y RF +y RX ) / 2. a=d b / 2 is the semi-major axis of the ellipse, c = d d / 2 is the focal length of the ellipse. Let θ be the semi-minor axis of the ellipse. β is the angle of rotation of the ellipse, positive for counterclockwise and negative for clockwise, and its value satisfies |β| = 90° - |θ|. d |

[0119] 4. The incident angle θ of the reflected link signal has been estimated. b_hat Another relationship (22) for the coordinates of the backscattering device is obtained as follows:

[0120]

[0121] 5. Considering the actual situation, y BD >y RX ;

[0122] 6. By combining the expressions in (21), (22), and (23), the coordinates of the backscattering device are obtained as follows:

[0123]

[0124] Where (x′) BD ,x′ BD The coordinates of the backscattering device after the ellipse in (21) is rotated and translated into a standard ellipse with its major axis on the x-axis are as follows: (24)

[0125]

[0126] Where a, b, and c are the semi-major axis, semi-minor axis, and focal length of the ellipse mentioned above, respectively, and k is the slope of the straight line between the scattering device and the receiver after rotation and translation, expressed as follows (25):

[0127] k = -tan(θ) d +θ b_hat (25)

[0128] The backscattering device positioning method of this application involves receiving a mixed signal, including a direct signal and a reflected signal; obtaining a first incident estimated angle of the direct signal and a second incident estimated angle of the reflected signal; obtaining a direct estimated signal and a reflected estimated signal based on the first and second incident estimated angles; obtaining a reflected link delay based on the direct and reflected estimated signals; obtaining a reflected link length based on the reflected link delay; and obtaining the coordinates of the backscattering device using an elliptic formula algorithm based on the RF source coordinates, receiver coordinates, reflected link length, first incident estimated angle, and second incident estimated angle, thereby enabling the positioning of the backscattering device.

[0129] In one embodiment, the transmission system bandwidth B = 10MHz, and the carrier f c =2.4GHz, OFDM subcarrier number N=512, cyclic prefix N cp =64, baseband sampling frequency f s =B=10MHz, sampling period T s =1 / B=0.1μs. Direct-link signal incident angle θ d = -30°, incident angle θ of the reflection link b =45°, α = 0.3 + 0.4j, number of uniform linear array antennas M = 8. The direct link length is set to 480 meters, and the total length of the reflected link is set to 600 meters. D is calculated based on the sampling rate and the speed of light. d =16 and D b =20. Let D d_part =10, corresponding to D b_part =14. And set the estimated D. d_part and D b_part The time window is T es_d =(N+N) cp ) = 576 and T es_b =(N+N) cp =576. The positioning accuracy is described using the positioning error radius, as detailed below (26):

[0130]

[0131] The experiment was repeated L times under the same simulation parameters, (x i ,y i (x) represents the coordinates of the backscattering device estimated in the i-th iteration. BD ,y BD ) are the actual coordinates of the backscattering device.

[0132] Figure 6 This is a schematic diagram of the structure of a positioning device for a backscattering device provided in an embodiment of this disclosure.

[0133] like Figure 6 As shown, the positioning device 600 for the backscattering device provided in this embodiment may include:

[0134] The receiving module 610 is used to receive a mixed signal, wherein the mixed signal includes a direct signal and a reflected signal;

[0135] The acquisition module 620 is used to acquire the first incident estimated angle of the direct signal and the second incident estimated angle of the reflected signal;

[0136] The acquisition module 620 is also used to acquire the direct projection estimation signal and the reflection estimation signal based on the first incident estimation angle and the second incident estimation angle;

[0137] The acquisition module 620 is also used to acquire the reflection link delay based on the direct estimation signal and the reflection estimation signal;

[0138] The acquisition module 620 is also used to obtain the reflection link length based on the reflection link delay;

[0139] The acquisition module 620 is also used to obtain the coordinates of the backscattering device using an elliptic formula algorithm based on the coordinates of the RF source, the coordinates of the receiver, the length of the reflection link, the first incident estimation angle, and the second incident estimation angle.

[0140] Figure 6 The positioning device for a backscattering device includes a receiving module for receiving mixed signals, wherein the mixed signals include direct signals and reflected signals; an acquisition module for acquiring a first incident estimated angle of the direct signal and a second incident estimated angle of the reflected signal; the acquisition module is also used to acquire direct estimated signals and reflected estimated signals based on the first incident estimated angle and the second incident estimated angle; the acquisition module is also used to acquire the reflected link delay based on the direct estimated signal and the reflected estimated signal; the acquisition module is also used to acquire the reflected link length based on the reflected link delay; and the acquisition module is also used to acquire the coordinates of the backscattering device using an elliptic formula algorithm based on the coordinates of the RF source, the coordinates of the receiver, the reflected link length, the first incident estimated angle, and the second incident estimated angle, thereby enabling the positioning of the backscattering device.

[0141] In one embodiment, the acquisition module 520 is further configured to acquire the first incident estimated angle of the direct signal and the second incident estimated angle of the reflected signal according to the root-music algorithm.

[0142] In one embodiment, the acquisition module 520 is further configured to acquire a first weight vector of the direct signal based on a first incident estimation angle; acquire a direct estimation signal of the direct signal based on the first weight vector and the mixed signal; acquire a second weight vector of the reflected signal based on a second incident estimation angle; and acquire a reflection estimation signal of the reflected signal based on the second weight vector and the mixed signal.

[0143] In one embodiment, the acquisition module 520 is further configured to acquire a first weight vector of the direct signal based on the first incident estimation angle using the Lagrange daily number method; and acquire a second weight vector of the reflected signal based on the second incident estimation angle using the Lagrange daily number method.

[0144] In one embodiment, the acquisition module 520 is further configured to acquire the direct propagation delay based on the direct estimated signal via cyclic prefix autocorrelation; acquire the reflection propagation delay based on the reflection estimated signal via cyclic prefix autocorrelation; and acquire the reflection link delay based on the direct link delay, the direct propagation delay, and the reflection propagation delay.

[0145] In one embodiment, the acquisition module 520 is further configured to acquire the center coordinates and focal length of the ellipse based on the coordinates of the radio frequency source and the receiver; acquire the semi-major axis of the ellipse based on the length of the reflection link; acquire the semi-minor axis based on the semi-major axis and the focal length; establish an ellipse formula based on the center coordinates, semi-major axis, semi-minor axis and the first incident estimated angle; and acquire the coordinates of the backscattering device based on the slope of the line connecting the backscattering device and the receiver and the ellipse formula.

[0146] See Figure 7 , Figure 7 This is a schematic diagram of the structure of a computer device 700 provided in an embodiment of this disclosure. Figure 7 As shown, the computer device in this embodiment may include one or more processors 701, a memory 702, and an input / output interface 703. The processor 701, memory 702, and input / output interface 703 are connected via a bus 704. The memory 702 stores a computer program, which includes program instructions. The input / output interface 703 receives and outputs data, such as for data interaction between the host machine and the computer device, or for data interaction between various virtual machines within the host machine. The processor 701 executes the program instructions stored in the memory 702.

[0147] The processor 701 can perform the following operations:

[0148] The system receives a mixed signal, which includes a direct signal and a reflected signal; obtains a first incident estimated angle of the direct signal and a second incident estimated angle of the reflected signal; obtains a direct estimated signal and a reflected estimated signal based on the first and second incident estimated angles; obtains a reflected link delay based on the direct estimated signal and the reflected estimated signal; obtains a reflected link length based on the reflected link delay; and obtains the coordinates of the backscattering device using an elliptic formula algorithm based on the coordinates of the RF source, the coordinates of the receiver, the reflected link length, the first incident estimated angle, and the second incident estimated angle.

[0149] In some feasible implementations, the processor 701 may be a central processing unit (CPU), but it can also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0150] The memory 702 may include read-only memory and random access memory, and provides instructions and data to the processor 701 and input / output interface 703. A portion of the memory 702 may also include non-volatile random access memory. For example, the memory 702 may also store device type information.

[0151] In practice, the computer device can execute the implementation methods provided by the steps in the above embodiments through its built-in functional modules. For details, please refer to the implementation methods provided by the steps in the above embodiments, which will not be repeated here.

[0152] This disclosure provides a computer device including a processor, an input / output interface, and a memory. The processor retrieves a computer program from the memory and executes the steps of the method shown in the above embodiments to perform a transmission operation.

[0153] This disclosure also provides a computer-readable storage medium storing a computer program adapted to be loaded by a processor and execute the methods provided in the steps of the above embodiments. Specific implementations of the steps in the above embodiments can be found therein and will not be repeated here. Furthermore, the beneficial effects of using the same method will not be repeated here either. For technical details not disclosed in the embodiments of the computer-readable storage medium involved in this disclosure, please refer to the description of the method embodiments of this disclosure. As an example, the computer program can be deployed to execute on a single computer device, or on multiple computer devices located in one location, or on multiple computer devices distributed across multiple locations and interconnected via a communication network.

[0154] The computer-readable storage medium can be the apparatus provided in any of the foregoing embodiments or the internal storage unit of the computer device, such as the hard disk or memory of the computer device. The computer-readable storage medium can also be an external storage device of the computer device, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc., provided on the computer device. Furthermore, the computer-readable storage medium can include both internal storage units and external storage devices of the computer device. The computer-readable storage medium is used to store the computer program and other programs and data required by the computer device. The computer-readable storage medium can also be used to temporarily store data that has been output or will be output.

[0155] This disclosure also provides a computer program product or computer program that includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the methods provided in the various alternative embodiments described above.

[0156] The terms "first," "second," etc., used in the specification, claims, and drawings of this disclosure are used to distinguish different objects, not to describe a specific order. Furthermore, the term "comprising," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, apparatus, product, or device that includes a series of steps or units is not limited to the listed steps or modules, but may optionally include steps or modules not listed, or may optionally include other step units inherent to these processes, methods, apparatuses, products, or devices.

[0157] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of each example have been generally described in terms of functionality. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this disclosure.

[0158] The methods and related apparatuses provided in this disclosure are described with reference to the method flowcharts and / or structural diagrams provided in this disclosure. Specifically, each block of the method flowchart and / or structural diagram, as well as combinations of blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions are provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable transmission device to create a machine, such that the instructions, which execute via the processor of the computer or other programmable transmission device, generate instructions for implementing the process. Figure 1 A schematic diagram of one or more processes and / or structures. Figure 1 The computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable transmission device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 A schematic diagram of one or more processes and / or structures. Figure 1 The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable transmission device to cause a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable device for implementing the process. Figure 1 A process or multiple processes and / or structures illustrate the steps of the functions specified in one or more boxes.

[0159] The above-disclosed embodiments are merely preferred embodiments of this disclosure and should not be construed as limiting the scope of this disclosure. Therefore, any equivalent variations made in accordance with the claims of this disclosure shall still fall within the scope of this disclosure.

Claims

1. A method for locating a backscattering device, characterized in that, include: Receive a mixed signal, wherein the mixed signal includes a direct signal and a reflected signal; Obtain the first incident estimated angle of the direct signal and the second incident estimated angle of the reflected signal; The direct incidence estimation signal and the reflection estimation signal are obtained based on the first incident estimation angle and the second incident estimation angle; The reflection link delay is obtained based on the direct projection estimation signal and the reflection estimation signal; The reflection link length is obtained based on the reflection link delay; The coordinates of the backscattering device are obtained using the elliptic formula algorithm based on the coordinates of the radio frequency source, the coordinates of the receiver, the length of the reflection link, the first incident estimated angle, and the second incident estimated angle. The process of obtaining the reflection link delay based on the direct projection estimation signal and the reflection estimation signal includes: The propagation delay of the direct portion is obtained by cyclic prefix autocorrelation based on the direct-projection estimated signal. The propagation delay of the reflected portion is obtained by cyclic prefix autocorrelation based on the estimated reflection signal. The reflection link delay is obtained based on the direct link delay, the propagation delay of the direct portion, and the propagation delay of the reflection portion; Obtaining the direct incidence estimation signal and the reflection estimation signal based on the first incident estimation angle and the second incident estimation angle includes: The first weight vector of the direct signal is obtained based on the first incident estimation angle; The direct estimation signal of the direct signal is obtained based on the first weight vector and the mixed signal; The second weight vector of the reflected signal is obtained based on the second incident estimation angle; The reflection estimation signal of the reflected signal is obtained based on the second weight vector and the mixed signal.

2. The method according to claim 1, characterized in that, Obtaining the first incident estimated angle of the direct signal and the second incident estimated angle of the reflected signal includes: The first incident angle of the direct signal and the second incident angle of the reflected signal are obtained according to the root-music algorithm.

3. The method according to claim 1, characterized in that, Obtaining the first weight vector of the direct signal based on the first incident estimation angle includes: The first weight vector of the direct signal is obtained based on the first incident estimation angle using the Lagrange daily number method; Obtaining the second weight vector of the reflected signal based on the second incident estimation angle includes: The second weight vector of the reflected signal is obtained based on the second incident estimated angle using the Lagrange daily number method.

4. The method according to claim 1, characterized in that, The coordinates of the backscattering device are obtained using an elliptic curve algorithm based on the coordinates of the RF source, the receiver, the reflection link length, the first incident estimated angle, and the second incident estimated angle. The coordinates of the ellipse center and the focal length of the ellipse are obtained based on the coordinates of the radio frequency source and the coordinates of the receiver. The semi-major axis of the ellipse is obtained based on the length of the reflection link. The semi-minor axis is obtained based on the semi-major axis and the focal length; An ellipse formula is established based on the center coordinates, the semi-major axis, the semi-minor axis, and the first incident estimated angle. The coordinates of the backscattering device are obtained based on the slope of the line connecting the backscattering device and the receiver, and the elliptic formula.

5. A positioning device for a backscattering device, characterized in that, include: A receiving module is used to receive a mixed signal, wherein the mixed signal includes a direct signal and a reflected signal; The acquisition module is used to acquire the first incident estimated angle of the direct signal and the second incident estimated angle of the reflected signal; The acquisition module is further configured to acquire the direct projection estimation signal and the reflection estimation signal based on the first incident estimation angle and the second incident estimation angle; wherein, acquiring the direct projection estimation signal and the reflection estimation signal based on the first incident estimation angle and the second incident estimation angle includes: acquiring a first weight vector of the direct projection signal based on the first incident estimation angle; acquiring a direct projection estimation signal of the direct projection signal based on the first weight vector and the mixed signal; acquiring a second weight vector of the reflection signal based on the second incident estimation angle; and acquiring a reflection estimation signal of the reflection signal based on the second weight vector and the mixed signal. The acquisition module is further configured to acquire a reflection link delay based on the direct-projection estimation signal and the reflection estimation signal; wherein, acquiring the reflection link delay based on the direct-projection estimation signal and the reflection estimation signal includes: acquiring the direct-projection propagation delay based on the direct-projection estimation signal through cyclic prefix autocorrelation; acquiring the reflection propagation delay based on the reflection estimation signal through cyclic prefix autocorrelation; and acquiring the reflection link delay based on the direct-projection link delay, the direct-projection propagation delay, and the reflection propagation delay. The acquisition module is further configured to acquire the reflection link length based on the reflection link delay; The acquisition module is further configured to obtain the coordinates of the backscattering device using an elliptic formula algorithm based on the coordinates of the radio frequency source, the coordinates of the receiver, the length of the reflection link, the first incident estimation angle, and the second incident estimation angle.

6. A computer device, characterized in that, Includes processor, memory, and input / output interfaces; The processor is connected to the memory and the input / output interface respectively, wherein the input / output interface is used to receive data and output data, the memory is used to store computer programs, and the processor is used to call the computer programs so that the computer device executes the method according to any one of claims 1-4.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program adapted to be loaded and executed by a processor, such that a computer device having the processor performs the method of any one of claims 1-4.

8. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the method described in any one of claims 1-4.

Images