Direct positioning method and system based on rotating array

Abstract

The invention provides a direct positioning method and system based on a rotating array, and belongs to the field of space-based passive positioning. The objective of the invention is to solve the problem of limited positioning performance caused by single received signal in a traditional fixed array structure. According to the invention, the radiation source signal is received by adopting the array structure which changes along with time, and interception signals under different array structures can be obtained by using fewer receiving stations, so that the accuracy of positioning estimation can be improved, and the equipment cost can be reduced; by using the rotating array, the system can receive signals from different directions and angles within the same time, and the signal acquisition efficiency and the response speed of the system are greatly improved; the method is suitable for real-time positioning and dynamic tracking tasks, and the overall working efficiency of the system is improved.

Description

Technical Field

[0001] The present invention relates to the field of space-based passive positioning technology, and in particular to a direct positioning method and system based on a rotating array. Background Art

[0002] Traditional positioning methods are usually two-step methods, that is, first estimating the arrival angle, time difference, frequency difference and other parameters of the received signal, and then calculating the position through geometric relationships. The direct positioning method can directly estimate the position of the radiation source from the received signal, and the positioning is more accurate in a low signal-to-noise ratio environment. For multi-satellite direct positioning, the positioning cost function, the array structure of the received signal, the signal processing method, etc. directly affect the positioning performance. However, the traditional array structure is generally a fixed array structure of the receiving station, and the single received signal leads to limited positioning performance. The present invention adopts a rotating array to receive signals. By adjusting the angle of the array, it can receive radiation source signals from different directions, expand the range of the received signal, and receive signals from different directions to form more baseline structures, thereby improving positioning accuracy. Summary of the invention

[0003] The technical problems to be solved by the present invention are:

[0004] In order to solve the problem that the traditional array structure is a fixed array structure and the received signal is single, resulting in limited positioning performance.

[0005] The present invention adopts the following technical solutions to solve the above technical problems:

[0006] The present invention provides a direct positioning method based on a rotation array, comprising the following steps:

[0007] S100, constructing a rotating array structure, deploying a rotating linear array on each observation satellite, rotating the rotating linear array clockwise around the center of the rotating linear array, and obtaining a position representation of each array element in the rotating linear array;

[0008] S200, constructing an observation signal model, and using a MUSIC-based method to obtain a positioning cost function based on a rotation array;

[0009] S300, considering the influence of the rotating elements of the rotating array, optimizing the signal propagation time from the satellite to the target, including calculating the signal delay, interval length and phase of the collected signal in the rotating elements;

[0010] S400, the positioning cost function constructed in step S200 estimates the position of the target based on the optimization of the signal propagation time in step S300 and taking into account the position of the satellite orbit, and then determines the precise position of the target by searching for the maximum value in the positioning cost function value.

[0011] Furthermore, in step S100, it includes:

[0012] A rotating linear array consisting of N array elements arranged in one or more rows is deployed on each observation satellite, rotating clockwise around the center of the rotating linear array at an angular velocity of ω; K signals are intercepted in each rotation period T = 2π / ω, and the rotation angle of each interception is θ k ,k=1,2,…,K, the duration of a single observation is T k ; During the kth observation period, the position of each array element is expressed as:

[0013]

[0014] Among them, d1 represents the position of all array elements relative to the reference array element at the first observation time, and the matrix represents the rotation matrix, t k represents the kth observation moment;

[0015]

[0016] d1=[ε1-ε0,ε2-ε0,…,ε N -ε0]

[0017] Among them, ε0 and ε n Indicates the position of the reference array element at the start time and the position of the nth array element.

[0018] Further, in step S200, the j-th sample outputted by the k-th observation array is:

[0019] r k,j =A k (ρ)s k,j +w k,j

[0020] Among them, s k,j Indicates the received signal, w k,j represents noise, ρ represents the location parameter of the radiation source;

[0021] The array response is:

[0022]

[0023] Where p represents the position of the radiation source, K k =2π×u k / λ is the wave number vector, u k represents the unit line of sight vector from the receiving station to the radiation source at the kth observation, and λ is the wavelength;

[0024] Construct a matrix from the array vectors corresponding to the jth sample in all observations: definition

[0025]

[0026] Then the observed signal model is:

[0027] r j =A(ρ)s j +w j

[0028] The positioning cost function based on the rotation array is obtained by using the MUSIC method:

[0029]

[0030] Among them, a k (p) represents the steering vector at the kth observation, represents the noise subspace matrix at the kth observation;

[0031] Since the positioning cost function is only related to the position of the radiation source, the maximum radiation source position P in the above positioning cost function is the estimated position of the radiation source.

[0032] Further, in step S300, including, S310, signal delay calculation, in order to specify the received signal, it is necessary to set the collection time t of each signal. c , determine the launch time t e (t c ) in a way that takes into account the motion of the rotating antenna:

[0033] t e (t c ) = t c -τ c (t c )

[0034] τ c (t c )=τ c,stat (t c )+τ c,v (t c )

[0035]

[0036] Where c represents the speed of light; τ c,v (t c ) represents the additional time increment for rotating the antenna; represents the position vector from the emission source to the rotating collector; represents the direction vector of the antenna source;

[0037] The position vector from the emitting source to the rotating collector The static propagation delay is:

[0038]

[0039] In the formula, The direction vector representing the static propagation delay time of the transmitting source; τ r，stat (t c ) represents the time required for the RF waveform

[0040] In the formula, the unit vector in the line of sight from the rotating collection element to the source is for:

[0041]

[0042] The effective sampling rate of the source signal within a single sampling time at the collector is given by:

[0043] t s,ef (t c )=[τ c (t c )-τ c (t c -t s )]+t s

[0044] Where, t s，ef (t c ) is the nominal sampling time t s The sum of τ c (t c -t s ) represents the time delay from the emission time to a single sampling time;

[0045]

[0046] In the formula, F s，ef (t) represents the expanded version of the source signal being collected.

[0047] Furthermore, in step S300, it further includes, S320, calculating the interval length, within an angle range of 180°, using a linear model:

[0048] F s,ef (t) = F s,ef (t o )+F′ s,ef (t)(tt o )=F s,ef (t o )+q×(tt o )

[0049] In the formula, F′ s，ef (t) is F s，efThe derivative of (t), q is a constant coefficient; t is the time of collecting signals; t0 is the time of initially transmitting signals;

[0050] In t o +t int The slope of a linear function over a time interval for:

[0051]

[0052] Among them, t int For task time;

[0053] The amount of sample mismatch allowed to occur within the interval limits this error to a certain range of sample size, namely:

[0054]

[0055] For the collection process, the time is determined to be relative to the rotational position, and for the effective source sampling rate, the process is repeated at the next time interval, and so on, until the rotating antenna completes the collection of half a revolution.

[0056] Furthermore, in step S300, it also includes, S330, calculating the phase of the collected signal, and the phase of the collected signal is:

[0057] Φ ck (t) = Φ ck =-ωτ ck +ΔΦ

[0058] In the formula, the phase of each collecting element is Φ ck , angular velocity is ω, angle is ΔΦ; τ ck is the angle of rotation of the static rod;

[0059] For each sample Φ c (n), in the interval τ c，stat (n=1) takes a rate within the duration, and the corresponding time is given by the following formula:

[0060]

[0061] In the formula, τ c Represents the period of the RF carrier frequency;

[0062] The sampling at the receiver of the rotating collector appears as t on the transmitted signal waveform due to the expansion or compression effect. s,ef ;

[0063] The acquisition signal is equivalent to the Doppler phenomenon:

[0064]

[0065] In the formula, is at time t cm Velocity vector of the rotating collector; represents the rotating collector at time t cm The direction vector of

[0066] v r，rad (tc m )t s is the radial velocity component, i.e., the component in the direction of the emission source;

[0067] In one cycle of airborne sampling, due to the radial motion of the collector, the sampling period of the incident signal undergoes a very small time increment, namely:

[0068]

[0069] Doppler frequency f c for:

[0070]

[0071] Where γ represents the wavelength of the RF carrier frequency;

[0072] The phase of the signal collected in the interval is expressed as:

[0073] Φ c (n)=-ωτ c,stat (n=1)+ΔΦ+2πf c (n-1)t s

[0074] A f c The effective Doppler frequency of the interval is:

[0075]

[0076] Among them, f s Represents the RF carrier frequency.

[0077] Furthermore, in step S400, a particle swarm optimization algorithm, Newton's method or genetic algorithm is used to search for the maximum value of the positioning cost function.

[0078] A direct positioning system based on a rotating array has a program module corresponding to the above steps, and executes the steps in the direct positioning method based on a rotating array when running.

[0079] A computer-readable storage medium stores a computer program, wherein the computer program is configured to implement the steps of a direct positioning method based on a rotation array when called by a processor.

[0080] Compared with the prior art, the present invention has the following beneficial effects:

[0081] The multi-satellite direct positioning method based on a rotating array proposed in the present invention adopts an array structure that changes with time to receive radiation source signals. Since the rotating array structure changes with time, fewer receiving stations can be used to obtain intercepted signals under different array structures, which is conducive to increasing the accuracy of positioning estimation and reducing equipment costs. The use of a rotating array enables the system to receive signals from different directions and angles in the same time, greatly improving the efficiency of signal acquisition and the response speed of the system. This makes the present invention suitable for real-time positioning and dynamic tracking tasks, and improves the overall work efficiency of the system.

[0082] Since the rotating array can flexibly adjust the receiving angle and array configuration, it can better adapt to complex and dynamic environmental changes. It can still maintain high positioning accuracy and reliability under different geographical conditions and signal transmission environments, and has strong environmental adaptability. By utilizing the structural changes of the rotating array, the need for multiple fixed array configurations is reduced, thereby reducing space and energy consumption. It is also easier to operate and control because the system does not need to rely on complex array layouts and frequent adjustments, further simplifying the installation and operation process. The rotating array structure allows the equipment to complete precise positioning tasks with fewer receiving stations and lower power consumption. Compared with traditional multi-array systems, this method can significantly reduce energy consumption under the same performance, meeting the requirements of energy conservation and emission reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] Figure 1 is a flow chart of a direct positioning method based on a rotating array in an embodiment of the present invention;

[0084] Figure 2 Schematic diagram of the geometric structure of the rotating array of the present invention. DETAILED DESCRIPTION

[0085] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0086] Specific implementation plan 1: Combine Figure 1 and Figure 2 As shown, the present invention provides a direct positioning method based on a rotation array, comprising the following steps:

[0087] S100, construct a rotating array structure,

[0088] Combination Figure 2As shown, a rotating linear array consisting of N array elements arranged in one or more rows is deployed on each observation satellite, rotating clockwise around the center of the rotating linear array at an angular velocity of ω; K signals are intercepted in each rotation period T = 2π / ω, and the rotation angle of each interception is θ k ,k=1,2,…,K, the duration of a single observation is T k , it is considered that the single observation time is very short, that is, the array structure is considered unchanged in a single observation; during the kth observation period, the position of each array element is expressed as:

[0089]

[0090] Among them, d1 represents the position of all array elements relative to the reference array element (the first array element in the array) at the first observation time, and the matrix represents the rotation matrix, t k represents the kth observation moment;

[0091]

[0092] d1=[ε1-ε0,ε2-ε0,…,ε N -ε0]

[0093] Among them, ε0 and ε n Indicates the position of the reference array element and the position of the nth array element at the start time;

[0094] S200, construct a signal model,

[0095] The jth sample of the kth observation array output is:

[0096] r k,j =A k (ρ)s k,j +w k,j

[0097] Among them, s k,j Indicates the received signal, w k,j represents noise, ρ represents the location parameter of the radiation source;

[0098] The array response is:

[0099]

[0100] Where p represents the position of the radiation source, K k =2π×u k / λ is the wave number vector, u k represents the unit line of sight vector from the receiving station to the radiation source at the kth observation, and λ is the wavelength;

[0101] Construct a matrix from the array vectors corresponding to the jth sample in all observations: definition Where, J is the total number of samples;

[0102]

[0103] Then the observed signal model is:

[0104] r j =A(ρ)s j +w j

[0105] The positioning cost function based on the rotation array is obtained by using the MUSIC method:

[0106]

[0107] Among them, a k (p) represents the steering vector at the kth observation, represents the noise subspace matrix at the kth observation; the cost function is only related to the position of the radiation source, and P that maximizes the above cost function is the estimated position of the radiation source;

[0108] S300, since the rotating antenna element brings certain complexity to signal processing, the attributes and parameters related to the concept of arrival time need to be identified and adjusted, and the rotating elements considered in the present invention include signal delay, interval length and phase of the collected signal;

[0109] S310, signal delay calculation,

[0110] To specify the received (baseband) signal, as shown below, it is necessary to set the collection time t for each signal c , determine the launch time t e (t c ) in a way that takes into account the motion of the rotating antenna:

[0111] t e (t c ) = t c -τ c (t c )

[0112] τ c (t c )=τ c,stat (t c )+τ c,v (t c )

[0113]

[0114] Where c represents the speed of light; τ c,v (t c) represents the additional time increment for rotating the antenna; represents the position vector from the emission source to the rotating collector; represents the direction vector of the antenna source;

[0115] The position vector from the emitting source to the rotating collector The static propagation delay is:

[0116]

[0117] In the formula, The direction vector representing the static propagation delay time of the transmitting source; the time τ required for the RF waveform r，stat (t c ) from the source to the collection point at the speed of light, the collector itself is moving, so the signal emission time can be correctly determined relative to t c It is necessary to include an additional increment of the signal flight time that is increased or decreased due to this movement of the collector; the additional time increment τ r，v (t c ) is the radial distance of the rotating antenna relative to the light source divided by the speed of light;

[0118] In the formula, the unit vector in the line of sight from the rotating collection element to the source is

[0119]

[0120] The compression and expansion effects produced by a rotating collector on the source signal are very similar to the Doppler effect. Consider a source signal sampled at some rate on the ground. Then at the rotating collector, even if sampling also occurs at that point, very slight motion towards or away from the source will produce a collected signal that has an aspect of expansion or compression relative to the transmitted source signal. In other words, it produces a version of the source signal that is effectively resampled at a slightly different sampling rate.

[0121] From this point in the source signal stream, the collected signal is a compressed or expanded version of the subsequent signal; for high-fidelity simulation, this compression / expansion characteristic is achieved by resampling the source signal at the effective sampling rate; the effective sampling rate of the source signal in a single sampling time at the collector is given by:

[0122] t s,ef (t c )=[τ c (t c )-τ c (t c -t s )]+t s

[0123] Where, ts，ef (t c ) is the nominal sampling time t s The sum of τ c (t c -t s ) represents the time delay from the emission time to a single sampling time;

[0124]

[0125] In the formula, F s，ef (t) represents the extended version of the source signal being collected; at this time t = t c ;

[0126] S320, interval length calculation,

[0127] Before the approximation of a constant sampling rate causes too much loss of fidelity, say 10% to 20%, the maximum rate of change occurs around 180°, within which it can be represented by a linear model:

[0128] F s,ef (t) = F s,ef (t o )+F′ s,ef (t)(tt o )=F s,ef (t o )+q×(tt o )

[0129] In the formula, F′ s，ef (t) is F s，ef The derivative of (t), q is a constant coefficient; t is the time of collecting signals; t0 is the time of initially transmitting signals;

[0130] In t o +t int The slope of a linear function over a time interval for:

[0131]

[0132] Among them, t int For task time;

[0133] The amount of sample mismatch allowed within the interval limits this error to within a certain range of sample sizes:

[0134]

[0135] For the collection process, it is determined that the time is related to the rotation position. For the effective source sampling rate, after a certain length of time, which can be 158ms, the process is repeated in the next time interval, and so on, until the rotating antenna completes the collection of half a circle;

[0136] S330, phase calculation of the collected signal,

[0137] The phase of the collected (baseband) signal is:

[0138] Φck(t)=Φck=-ωτck+ΔΦ

[0139] In the formula, the phase of each collecting element is Φ ck , angular velocity ω, angle ΔΦ; τ ck is the angle of rotation of the static rod;

[0140] For the rotating collecting element, as has been described previously, the motion produces an expansion / compression effect on the complex envelope of the transmitted signal, and the phase of the RF carrier is also disturbed accordingly; this effect is also evident in the baseband acquired signal, but it is not automatically imposed on this signal by the resampling process; instead, it must be imposed numerically based on an analytical model; this effect is usually interpreted as a Doppler shift of the carrier frequency, but in order to obtain maximum clarity in the following derivation, the same quantity used throughout is adopted, and the following is the mathematically derived formula equivalent to the Doppler shift representation;

[0141] For the phase of the signal collected from a certain time, for each sample Φ c (n), in the interval τ c，stat (n = 1) takes a rate within the duration, where the corresponding time is given by:

[0142]

[0143] In the formula, τ c Represents the period of the RF carrier frequency;

[0144] The sampling at the receiver of the rotating collector appears in the transmitted signal waveform due to the expansion / compression effect.

[0145] t s,ef ; To prove the equivalence with the Doppler phenomenon, the formula is as follows:

[0146]

[0147] In the formula, is at time t cm Velocity vector of the rotating collector; represents the rotating collector at time t cm The direction vector of

[0148] v r，rad (tc m )t s is the radial velocity component, i.e. its component in the direction of the emission source; during one cycle of the onboard sampling, the sampling period of the incident signal undergoes a very small time increment due to the radial motion of the collector:

[0149]

[0150] Doppler frequency f c for:

[0151]

[0152] Where γ represents the wavelength of the RF carrier frequency;

[0153] In terms of Doppler frequency, the phase of the signal collected within the interval can be expressed as:

[0154] Φ c (n)=-ωτ c,stat (n=1)+ΔΦ+2πf c (n-1)t s

[0155] A f c The effective Doppler frequency of the interval is:

[0156]

[0157] Among them, f s represents the RF carrier frequency;

[0158] Specific implementation scheme 2: The present invention provides a direct positioning system based on a rotating array, which has a program module corresponding to the above steps and executes the steps in the above direct positioning method based on a rotating array during operation.

[0159] The other combinations and connection relationships of this embodiment are the same as those of the first embodiment.

[0160] Specific implementation scheme three: The present invention provides a computer-readable storage medium, which stores a computer program, and the computer program is configured to implement the steps of a direct positioning method based on a rotation array when called by a processor.

[0161] The other combinations and connection relationships of this embodiment are the same as those of the first embodiment.

[0162] Simulation experiment

[0163] Dynamic object localization in urban environments

[0164] Step 1: Set up a dual-satellite positioning scenario equipped with a rotating array, where each satellite is equipped with a rotating array receiving antenna. The rotating array antenna consists of multiple antenna elements and can adjust the receiving direction by rotation to receive radiation source signals from dynamic targets on the ground. In the simulation environment, it is assumed that the target is a fast-moving vehicle, and the radar pulse signal with a transmission frequency of 1GHz is assumed. Assuming that there is no multipath effect in the environment, the propagation of the radar pulse signal is only affected by the target speed and distance. The radar pulse signal is emitted from the target vehicle and propagates through free space to the satellite. The signal propagation time τ is determined by the distance d between the target and the satellite, and the formula is: Where c is the speed of light;

[0165] Step 2: At each observation moment, the dual-satellite array receives radar pulse signals from the target vehicle through a rotating array. Each satellite collects signals 100 times per second to ensure that sufficient signals are received for positioning estimation when the target changes dynamically. At each sampling, the rotating array antenna adjusts the receiving direction according to the preset rotation mode to capture signals from different directions. The received signal is demodulated to extract the time delay and phase information. By comparing the time difference of the signals received by the two satellites, the distance difference between the target and the two satellites can be calculated.

[0166] Step 3: Based on the received signal data, a cost function is constructed that is optimized based on the possible locations of the target and the signal propagation time from the satellite to the target. The cost function calculates the possible coordinates of the target by taking into account the time delay of the satellite signal and the known orbital position. For each satellite, the target position (x, y) is calculated in relation to the satellite position (x i ,y i ,z i ) i :

[0167] Signal propagation time

[0168] Cost Function in is the actual propagation time calculated from the received signal. The goal is to find the most likely location of the target by minimizing J(x,y).

[0169] Step 4: Determine the estimated position of the target by searching for the point with the maximum cost function value. During the search process, the particle swarm optimization algorithm can be used to improve the calculation efficiency and accuracy, and finally obtain the precise coordinates of the target position. For each particle, calculate its corresponding cost function value J(x, y) and update the particle position and velocity according to the rules of the particle swarm optimization algorithm: v k+1 =w·vk +c1·r1·(p best -x k )+c2·r2·(g best -x k )

[0170] ·x k+1 =x k +v k+1

[0171] Where w is the inertia weight, c1 and c2 are learning factors, r1 and r2 are random numbers, p best is the particle's best historical position, g best is the global optimal position.

[0172] Offshore platform positioning

[0173] Step 1: Set up a dual-satellite positioning system with a rotating array. The satellite array is equipped to receive radar pulse signals transmitted by the offshore platform. The carrier frequency of the radar signal is set to 1GHz, and the signal propagation is assumed to be linear propagation without multipath effects. The offshore platform moves on the sea surface at a constant speed and transmits radar pulse signals for positioning.

[0174] Step 2: Each satellite receives radar signals from the offshore platform at different observation times through a rotating array. Since the platform is located in the sea far away from the land, the propagation of the signal is mainly affected by the reflection of the sea surface, so the quality of the received signal is high and is not affected by obstacles such as urban buildings.

[0175] Step 3: Based on the received radar signal, construct a cost function. This cost function estimates the position of the offshore platform by modeling the signal propagation delay between the satellite and the offshore platform and taking into account the orbital position of the satellite. For each satellite, calculate the target position (x, y) and the satellite position (x i ,y i ,z i ) i :

[0176] Signal propagation time

[0177] Cost Function in is the actual propagation time calculated from the received signal. The goal is to find the most likely location of the target by minimizing J(x,y).

[0178] Step 4: Use an optimization algorithm (such as Newton's method or genetic algorithm) to search for the maximum value of the cost function to determine the precise location of the offshore platform. This process can effectively eliminate signal noise and obtain a more accurate positioning result. The Newton method is suitable for local search by iteratively approximating the optimal solution; the genetic algorithm simulates the natural selection process for global search and is suitable for complex nonlinear problems.

[0179] Newton's method search process:

[0180] Initialize the platform position estimate (x0, y0);

[0181] Calculate the gradient of the cost function and the Hessian matrix H(J(x,y));

[0182] Update the platform position estimate:

[0183] The iterations are repeated until convergence, and the optimal position estimate of the platform is obtained.

[0184] Genetic algorithm search process:

[0185] Initialize a group of individuals, each of which represents a possible platform position (x, y);

[0186] Calculate the fitness of each individual (i.e., the cost function value);

[0187] Generate a new generation of individuals through selection, crossover and mutation operations;

[0188] Repeat the iteration until convergence to obtain the optimal position estimate of the platform;

[0189] When the optimization algorithm converges, the optimal position (x*, y*) is the estimated position of the platform;

[0190] Through multiple iterations and optimization, the precise coordinates of the platform position can be obtained.

[0191] Although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A direct positioning method based on a rotating array, characterized in that: The following steps are involved: S100, constructing a rotating array structure, deploying a rotating linear array on each observation satellite, rotating the rotating linear array clockwise around the center of the rotating linear array, and obtaining a position representation of each array element in the rotating linear array; S200, constructing an observation signal model, and using a MUSIC-based method to obtain a positioning cost function based on a rotation array; S300, considering the influence of the rotating elements of the rotating array, optimizing the signal propagation time from the satellite to the target, including calculating the signal delay, interval length and phase of the collected signal in the rotating elements; S400, the positioning cost function constructed in step S200 estimates the position of the target based on the optimization of the signal propagation time in step S300 and taking into account the position of the satellite orbit, and then determines the precise position of the target by searching for the maximum value in the positioning cost function value.

2. A direct positioning method based on a rotating array according to claim 1, characterized in that: In step S100, it includes: A rotating linear array consisting of N array elements arranged in one or more rows is deployed on each observation satellite, rotating clockwise around the center of the rotating linear array at an angular velocity of ω; K signals are intercepted in each rotation period T = 2π / ω, and the rotation angle of each interception is θ k ,k=1,2,…,K, the duration of a single observation is T k ; During the kth observation period, the position of each array element is expressed as: Among them, d1 represents the position of all array elements relative to the reference array element at the first observation time, and the matrix represents the rotation matrix, t k represents the kth observation moment; d1=[ε1-ε0,ε2-ε0,…,ε N -e0] Among them, ε0 and ε n Indicates the position of the reference array element at the start time and the position of the nth array element.

3. A direct positioning method based on a rotating array according to claim 2, characterized in that: In step S200, the j-th sample of the k-th observation array output is: r k,j =A k (p)s k,j +w k,j Among them, s k,j Indicates the received signal, w k,j represents noise, ρ represents the location parameter of the radiation source; The array response is: Where p represents the position of the radiation source, K k =2π×u k / λ is the wave number vector, u k represents the unit line of sight vector from the receiving station to the radiation source at the kth observation, and λ is the wavelength; Construct a matrix from the array vectors corresponding to the jth sample in all observations: definition Then the observed signal model is: r j =A(ρ)s j +w j The positioning cost function based on the rotation array is obtained by using the MUSIC method: Among them, a k (p) represents the steering vector at the kth observation, represents the noise subspace matrix at the kth observation; Since the positioning cost function is only related to the position of the radiation source, the maximum radiation source position P in the above positioning cost function is the estimated position of the radiation source.

4. The direct positioning method based on a rotating array according to claim 3, characterized in that: In step S300, including, S310, signal delay calculation, in order to specify the received signal, it is necessary to set the collection time t for each signal c , determine the launch time t e (t c ) in a way that takes into account the motion of the rotating antenna: t e (t c )=t c -τ c (t c ) t c (t c )=τ c,stat (t c )+τ c,v (t c ) Where c represents the speed of light; τ c,v (t c ) represents the additional time increment for rotating the antenna; represents the position vector from the emission source to the rotating collector; represents the direction vector of the antenna source; The position vector from the emitting source to the rotating collector The static propagation delay is: In the formula, The direction vector representing the static propagation delay time of the transmitting source; τ r，stat (t c ) represents the time required for the RF waveform In the formula, the unit vector in the line of sight from the rotating collection element to the source is for: The effective sampling rate of the source signal within a single sampling time at the collector is given by: t s,ef (t c )=[τ c (t c )-τ c (t c -t s )]+t s Where, t s，ef (t c ) is the nominal sampling time t s The sum of τ c (t c -t s ) represents the time delay from the emission time to a single sampling time; In the formula, F s，ef (t) represents the expanded version of the source signal being collected.

5. The direct positioning method based on a rotating array according to claim 4, characterized in that: In step S300, the method further includes, S320, calculating the interval length within an angle range of 180°, using a linear model: F s,ef (t)=F s,ef (t o )+F′ s,ef (t)(t-t o )=F s,ef (t o )+q×(t-t o ) In the formula, F′ s，ef (t) is F s，ef The derivative of (t), q is a constant coefficient; t is the time of collecting signals; t0 is the time of initially transmitting signals; In t o +t int The slope of a linear function over a time interval for: Among them, t int For task time; The amount of sample mismatch allowed to occur within the interval limits this error to a certain range of sample size, namely: or For the collection process, the time is determined to be relative to the rotational position, and for the effective source sampling rate, the process is repeated at the next time interval, and so on, until the rotating antenna completes the collection of half a revolution.

6. A direct positioning method based on a rotating array according to claim 5, characterized in that: In step S300, it also includes, S330, calculating the phase of the collected signal, and the phase of the collected signal is: F ck (t)=Φ ck =-ot ck +DF In the formula, the phase of each collecting element is Φ ck , angular velocity is ω, angle is ΔΦ; τ ck is the angle of rotation of the static rod; For each sample Φ c (n), in the interval τ c，stat (n=1) takes a rate within the duration, and the corresponding time is given by the following formula: In the formula, τ c Represents the period of the RF carrier frequency; The sampling at the receiver of the rotating collector appears as t on the transmitted signal waveform due to the expansion or compression effect. s,ef ; The acquisition signal is equivalent to the Doppler phenomenon: In the formula, is at time t cm Velocity vector of the rotating collector; represents the rotating collector at time t cm The direction vector of v r，rad (t cm )t s is the radial velocity component, i.e., the component in the direction of the emission source; In one cycle of airborne sampling, due to the radial motion of the collector, the sampling period of the incident signal undergoes a very small time increment, namely: Doppler frequency f c for: Where γ represents the wavelength of the RF carrier frequency; The phase of the signal collected in the interval is expressed as: F c (n)=-ot c,stat (n=1)+ΔΦ+2πf c (n-1)t s A f c The effective Doppler frequency of the interval is: Among them, f s Represents the RF carrier frequency.

7. A direct positioning method based on a rotation array according to claim 6, characterized in that: In step S400, a particle swarm optimization algorithm, Newton's method or genetic algorithm is used to search for the maximum value of the positioning cost function.

8. A direct positioning system based on a rotating array, characterized in that: The system has a program module corresponding to the steps of any one of claims 1 to 7, and executes the steps of the direct positioning method based on the rotating array when running.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and the computer program is configured to implement the steps of the direct positioning method based on a rotation array according to any one of claims 1 to 7 when called by a processor.

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