Multi-target rapid direction finding method and system based on single snapshot data

Abstract

The invention relates to the technical field of electromagnetic signal processing, and provides a multi-target rapid direction finding method and system based on single snapshot data. A multi-target fast direction finding method based on single snapshot data comprises the following steps: dividing a space where K signals are located according to a certain angle grid interval to obtain coarse estimation of a direction angle of each signal; based on the rough estimation of each signal direction angle, calculating amplitudes of K signals, carrying out K cycles, and carrying out one correction to obtain a current to-be-estimated signal which is only reserved in each cycle; based on the to-be-estimated signal of the current cycle, carrying out secondary correction by adopting an angle deviation-based closed expression to obtain a signal direction angle; and carrying out loop iteration on the processes of the primary correction and the secondary correction until the difference value between the signal direction angles of two adjacent cycles of each signal is smaller than a preset threshold value, ending the cycles, and outputting the signal direction angles of all the signals. According to the invention, fast and high-precision direction finding of multiple targets is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic signal processing, and in particular to a multi-target rapid direction finding method and system based on single snapshot data. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] The actual electromagnetic environment is complex and changeable. When multiple targets exist at the same time, how to quickly and accurately find the direction of multiple targets has become an urgent problem to be solved. The traditional method of target direction finding based on multi-snapshot data requires a long time to accumulate received data and cannot guarantee fast direction finding of multiple targets. In addition, some traditional target direction finding methods divide the spatial angle according to a certain angle grid interval, assuming that the direction angle of the estimated signal is estimated at the discrete sampling grid points, ignoring the deviation caused by the angle grid, and seriously reducing the estimation accuracy. Summary of the invention

[0004] In order to solve the technical problems existing in the above-mentioned background technology, the present invention provides a multi-target rapid direction finding method and system based on single snapshot data. On the basis of the single snapshot received signal, a method combining coarse estimation of the target direction angle and multiple cyclic iterative correction of the angle deviation generated by the coarse estimation is adopted to realize rapid and high-precision direction finding of multiple targets.

[0005] In order to achieve the above object, the present invention adopts the following technical solution: A first aspect of the present invention provides a multi-target rapid direction finding method based on single snapshot data.

[0006] A multi-target rapid direction finding method based on single snapshot data, comprising: Perform beamforming on all received single-snapshot signals, and search for K signals whose signal values ​​are greater than a set threshold after beamforming; divide the space where the K signals are located according to a certain angle grid interval to obtain a rough estimate of the direction angle of each signal; Based on the rough estimation of the direction angle of each signal, the amplitudes of K signals are calculated, K cycles are performed, and a correction is performed to obtain only the current signal to be estimated that is retained in each cycle; Based on the signal to be estimated in the current cycle, a secondary correction is performed using a closed-form expression based on the angle deviation to obtain the signal direction angle; The process of primary correction and secondary correction is iterated in a loop until the difference between the signal direction angles of two adjacent cycles of each signal is less than a preset threshold. The loop ends and the signal direction angles of all signals are output.

[0007] Furthermore, the space where the K signals are located is divided according to a certain angular grid interval to obtain a rough estimate of the direction angle of each signal; the method includes: dividing the space where the K signals are located according to a certain angular grid interval, locating the angle of each signal at the nearest discrete sampling grid point, and obtaining a rough estimate of the direction angle of each signal.

[0008] Furthermore, the rough estimation based on the direction angle of each signal is used to calculate the amplitudes of K signals, perform K cycles, perform a correction, and obtain only the current signal to be estimated that is retained in each cycle; it is expressed by the following formula:

[0009] in, Indicates k A signal is the current signal to be estimated; Indicates the signal received in each cycle, Indicates i The amplitude of a signal, Indicates i A rough estimate of the signal direction angle.

[0010] Furthermore, the signal to be estimated based on the current cycle is corrected twice using a closed-form expression based on an angle deviation to obtain a signal direction angle; the method includes: conjugate multiplying the signal to be estimated in the current cycle received by two adjacent array elements, taking the phase after the multiplication, and constructing a closed-form expression based on the angle deviation based on the multiplied phase and the covariance matrix of the noise difference vector of the two adjacent array elements to obtain the signal direction angle.

[0011] Furthermore, the conjugate multiplication of the signals to be estimated in the current cycle received by two adjacent array elements is expressed by the following formula:

[0012] in, Indicates n The estimated signal of the current cycle received by +1 array element is the same as the n The signal to be estimated in the current cycle received by each array element is conjugate multiplied to form a new value. Indicates k The amplitude of a signal, is the position difference between two adjacent array elements, is the unknown angle of the incoming wave direction of the kth signal to be estimated, is the noise difference between two adjacent array elements.

[0013] Furthermore, the closed-form expression based on the angle deviation is described by the following formula:

[0014] in, Indicates the signal direction angle, represents the inverse matrix of the covariance matrix of the noise difference vector, For phase.

[0015] A second aspect of the present invention provides a multi-target rapid direction finding system based on single snapshot data.

[0016] A multi-target rapid direction finding system based on single snapshot data, comprising: A rough estimation module is configured to: perform beamforming on all received single-snapshot received signals, and search for K signals whose signal values ​​are greater than a set threshold after beamforming; divide the space where the K signals are located according to a certain angle grid interval to obtain a rough estimate of the direction angle of each signal; A primary correction module is configured to: calculate the amplitudes of K signals based on a rough estimate of the direction angle of each signal, perform K cycles, perform a correction, and obtain only the current signal to be estimated that is retained in each cycle; A secondary correction module is configured to: perform secondary correction based on the signal to be estimated in the current cycle by using a closed-form expression based on the angle deviation to obtain a signal direction angle; The iterative loop and output module is configured to: iterate the process of primary correction and secondary correction until the difference between the signal direction angles of each signal in two adjacent cycles is less than a preset threshold, the loop ends, and the signal direction angles of all signals are output.

[0017] A third aspect of the present invention provides a computer-readable storage medium.

[0018] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps in the multi-target rapid direction finding method based on single snapshot data as described in the first aspect above.

[0019] A fourth aspect of the present invention provides a computer device.

[0020] A computer device comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps in the multi-target rapid direction finding method based on single snapshot data as described in the first aspect above are implemented.

[0021] A fifth aspect of the present invention provides a computer program product or a computer program.

[0022] The present invention provides a computer program product or a computer program, which 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 the processor executes the computer instructions, so that the computer device executes the steps in the multi-target rapid direction finding method based on single snapshot data as described in the first aspect above.

[0023] Compared with the prior art, the present invention has the following beneficial effects: The present invention proposes a multi-target rapid direction finding method and system based on single snapshot data, which can overcome the problem of slow target direction finding speed caused by the need for long-term accumulation of received data, and can also overcome the problem of low target direction finding accuracy caused by angle deviation caused by fixed angle grid interval. By receiving and processing single snapshot data and cyclically iteratively correcting the target direction angle, rapid and high-precision direction finding for multiple targets can be achieved.

[0024] The present invention makes a rough estimate of the target direction angle based on a single snapshot received signal, and can quickly find the direction of the target without accumulating more snapshot data for a long time; then, based on the closed-form expression of the angle deviation obtained by analysis, the angle deviation generated by the rough estimate is corrected for multiple cycles of iterations. In the process of the cyclic iteration correction, only one signal angle is corrected in each cycle, and the remaining signals except the signal to be estimated in the current cycle are subtracted from the received signal. By correcting all signal angles through multiple cycles of iterations, the direction finding accuracy of multiple targets is improved, and high-precision direction finding of the targets is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0026] Figure 1 is a flow chart of a multi-target rapid direction finding method based on single snapshot data shown in the present invention; Figure 2 is a curve diagram showing the variation of mean square error with signal-to-noise ratio in the case of a single real signal shown in the present invention; Figure 3 is a curve diagram showing a change in mean square error with signal-to-noise ratio in the case of a single complex signal shown in the present invention; Figure 4 is a curve diagram showing the variation of mean square error with signal-to-noise ratio in the case of multiple real number signals shown in the present invention; Figure 5 is a curve diagram showing the variation of mean square error with signal-to-noise ratio in the case of multiple complex signals shown in the present invention; Figure 6It is a structural diagram of a multi-target rapid direction finding system based on single snapshot data shown in the present invention. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0028] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0029] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0030] It should be noted that the flowcharts and block diagrams in the accompanying drawings illustrate the possible implementation architecture, functions and operations of the methods and systems according to various embodiments of the present disclosure. It should be noted that each box in the flowchart or block diagram can represent a module, a program segment, or a part of a code, and the module, program segment, or a part of a code may include one or more executable instructions for implementing the logical functions specified in each embodiment. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, or they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the flowchart and / or block diagram, and the combination of boxes in the flowchart and / or block diagram can be implemented using a dedicated hardware-based system that performs a specified function or operation, or can be implemented using a combination of dedicated hardware and computer instructions.

[0031] Signal perception and processing in complex electromagnetic environments can better recognize and understand the surrounding environment. Target direction finding is an important part of signal perception and processing, which determines the direction of its source by receiving and analyzing radio waves. When there are multiple moving targets in a complex environment, the time and accuracy of signal direction finding become the focus of attention. It is necessary to study fast and high-precision direction finding methods for multiple targets in complex environments. The present invention proposes a multi-target fast direction finding method and system based on single snapshot data. The invention is described in detail through several embodiments below: Embodiment 1 like Figure 1As shown, this embodiment provides a multi-target rapid direction finding method based on single snapshot data. This embodiment uses the method applied to a server as an example for illustration. It can be understood that the method can also be applied to a terminal, and can also be applied to a terminal, a server, and a system, and is implemented through the interaction between the terminal and the server. The server can be an independent physical server, or a server cluster or a distributed system composed of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network servers, cloud communications, middleware services, domain name services, security services CDN, and big data and artificial intelligence platforms. The terminal can be a smart phone, a tablet computer, a laptop computer, a desktop computer, a smart speaker, a smart watch, etc., but is not limited thereto. The terminal and the server can be directly or indirectly connected via wired or wireless communication, which is not limited in this application. In this embodiment, the method includes the following steps: Perform beamforming on all received single-snapshot signals, and search for K signals whose signal values ​​are greater than a set threshold after beamforming; divide the space where the K signals are located according to a certain angle grid interval to obtain a rough estimate of the direction angle of each signal; Based on the rough estimation of the direction angle of each signal, the amplitudes of K signals are calculated, K cycles are performed, and a correction is performed to obtain only the current signal to be estimated that is retained in each cycle; Based on the signal to be estimated in the current cycle, a secondary correction is performed using a closed-form expression based on the angle deviation to obtain the signal direction angle; The process of primary correction and secondary correction is iterated in a loop until the difference between the signal direction angles of two adjacent cycles of each signal is less than a preset threshold. The loop ends and the signal direction angles of all signals are output.

[0032] The present invention estimates the target direction angle based on a single snapshot received signal and can quickly find the direction of a moving target.

[0033] The multi-target rapid direction finding method based on single snapshot data described in this embodiment is described in detail below. The method includes: Step 1: Assume that the number of signals to be estimated is , the spatial angle of the signal to be estimated is divided according to a certain angle grid interval, and the direction angle of the estimated signal is not on the discrete sampling grid point. First, the single snapshot received signal is beamformed, and after the search beam is formed The position of the maximum value of the signal is determined, and the angle is positioned on the grid closest to the true angle to obtain a rough estimate of the direction angle of the signal to be estimated.

[0034] Step 2: Based on the rough estimate of the signal direction angle, calculate Signal amplitude .for Cycles (only one signal is corrected in each cycle, a total of In each cycle, the remaining signals except the signal to be estimated in the current cycle are subtracted from the received signal. The specific formula is as follows: .

[0035] in, Indicates k A signal, Indicates the signal received in each cycle, Indicates i The amplitude of a signal, Indicates i It is worth noting that each cycle only corrects the current signal angle to be estimated, that is, Signal Angle .

[0036] The present invention corrects only one signal angle in each cycle, and reduces the influence of other signals on the signal to be estimated in the current cycle as much as possible. Multiple cycle iterations can correct all signal angles one by one, and realize simultaneous direction finding of multiple targets.

[0037] Step 3: The rough estimation of the signal direction angle obtained by beamforming is essentially to approximate the signal estimation direction angle to the nearest angle grid point, resulting in a certain estimation error. Therefore, for the current cycle to be estimated signal, a method based on the angle deviation closed-form expression is proposed to further correct the angle deviation to obtain a high-precision signal direction angle.

[0038] Regarding step 3, the detailed steps of the method provided by this solution are as follows: Step 301: When solving the closed-form expression based on the angle deviation, firstly, conjugate multiplication is performed on the received signal data of two adjacent array elements, and then the phase of the data is obtained after the multiplication. The phase includes the position difference between the two adjacent array elements, the unknown angle of the incoming wave direction, and the noise difference between the two adjacent array elements. The specific formula is as follows:

[0039] in, Indicates n The signal received by the +1 antenna (element) is the same as the n The new value is formed by conjugating and multiplying the signals received by the root antennas (array elements). Indicates k The amplitude of a signal, is the position difference between two adjacent array elements, is the unknown angle of the incoming wave direction of the kth signal to be estimated, is the noise difference between two adjacent array elements.

[0040]

[0041] in, is the phase of the data.

[0042] The above formula is obtained by conjugate multiplication of the data of the kth signal received by two adjacent array elements. Therefore, the phase of both the complex and real signals will be eliminated during the conjugate multiplication process, and will not affect subsequent processing. Therefore, the present invention is applicable to both real and complex signal direction finding, and simulation verification results are given. For single or multiple real or complex signals, the mean square error of direction finding can approach the Cramer-Rao bound, achieving high-precision direction finding.

[0043] Step 302: Since the noise difference vectors of two adjacent array elements conform to the Gaussian distribution, the covariance matrix of the noise difference vectors is It can be obtained according to the existing method, and the present invention will not be described in detail here.

[0044] Step 303: Covariance matrix of the noise difference vector obtained based on the above steps , the closed-form expression based on the angle deviation can be calculated by the weighted least squares method, and the true direction angle of the signal can be corrected by the rough estimate of the signal angle through the closed-form expression based on the angle deviation. The specific formula is as follows: , .

[0045] in, Indicates about The weighted least squares function of Indicates the signal direction angle.

[0046] Step 4: Iterate step 2 and step 3 until the signal direction angle of two adjacent cycles is less than a preset threshold for each signal, and then the loop ends. Finally, the performance of the method is simulated and evaluated under different direction angles of multiple signals.

[0047] Regarding step 4, the detailed performance evaluation scheme provided by this solution is as follows: The Cramer-Rao bound is an important criterion for measuring the accuracy of signal angle estimation. The Cramer-Rao bound is affected by factors such as the angle of the signal in different directions and the number of snapshots. It is worth noting that the method proposed in the present invention is based on single snapshot data, so the simulation analysis does not consider the impact of the number of snapshots on the performance of the method. The present invention has conducted simulation experiments. Figure 2 is a curve diagram showing the variation of mean square error with signal-to-noise ratio in the case of a single real signal shown in the present invention; Figure 3is a curve diagram showing a change in mean square error with signal-to-noise ratio in the case of a single complex signal shown in the present invention; Figure 4 is a curve diagram showing the variation of mean square error with signal-to-noise ratio in the case of multiple real number signals shown in the present invention; Figure 5 It is a curve diagram of the change of mean square error with signal-to-noise ratio in the case of multiple complex signals shown in the present invention. 200 Monte Carlo analyses are used for statistics in the simulation to give a curve of the change of signal angle estimation mean square error with signal-to-noise ratio, and compare it with the Cramer-Rao bound of the method proposed in the present invention. It is shown that the angle estimation error of the multi-target rapid direction finding method based on single snapshot data proposed in the present invention can approach the Cramer-Rao bound, thereby achieving high-precision signal direction finding.

[0048] The present invention improves the target direction finding accuracy by adopting a method combining a rough estimation of the target direction angle with a multiple-cycle iterative correction of the angle deviation generated by the rough estimation. At the same time, the Cramer-Rao bound is used as a standard for measuring the signal angle estimation accuracy. The direction finding method proposed by the present invention can approach the Cramer-Rao bound under different signal numbers, real signals and complex signals, thereby achieving high-precision target direction finding.

[0049] Embodiment 2 This embodiment provides a multi-target rapid direction finding system based on single snapshot data.

[0050] like Figure 6 As shown, a multi-target rapid direction finding system based on single snapshot data includes: A rough estimation module is configured to: perform beamforming on all received single-snapshot received signals, and search for K signals whose signal values ​​are greater than a set threshold after beamforming; divide the space where the K signals are located according to a certain angle grid interval to obtain a rough estimate of the direction angle of each signal; A primary correction module is configured to: calculate the amplitudes of K signals based on a rough estimate of the direction angle of each signal, perform K cycles, perform a correction, and obtain only the current signal to be estimated that is retained in each cycle; A secondary correction module is configured to: perform secondary correction based on the signal to be estimated in the current cycle by using a closed-form expression based on the angle deviation to obtain a signal direction angle; The iterative loop and output module is configured to: iterate the process of primary correction and secondary correction until the difference between the signal direction angles of each signal in two adjacent cycles is less than a preset threshold, the loop ends, and the signal direction angles of all signals are output.

[0051] In some embodiments, the rough estimation module is further configured to: divide the space where the K signals are located according to a certain angle grid interval, locate the angle of each signal at the nearest discrete sampling grid point, and obtain a rough estimate of the direction angle of each signal.

[0052] In some embodiments, the method performed by the primary correction module is expressed by the following formula:

[0053] in, Indicates k A signal is the current signal to be estimated; Indicates the signal received in each cycle, Indicates i The amplitude of a signal, Indicates i A rough estimate of the signal direction angle.

[0054] In some embodiments, the secondary correction module is further configured to: perform conjugate multiplication on the signals to be estimated in the current cycle received by two adjacent array elements, take the phase after the multiplication, and construct a closed-form expression based on the angle deviation based on the phase after the multiplication and the covariance matrix of the noise difference vector of the two adjacent array elements, and solve to obtain the signal direction angle.

[0055] In some embodiments, the conjugate multiplication of the signals to be estimated in the current cycle received by two adjacent array elements is expressed by the following formula:

[0056] in, Indicates n The estimated signal of the current cycle received by +1 array element is the same as the n The signal to be estimated in the current cycle received by each array element is conjugate multiplied to form a new value. Indicates k The amplitude of a signal, is the position difference between two adjacent array elements, is the unknown angle of the incoming wave direction of the kth signal to be estimated, is the noise difference between two adjacent array elements.

[0057] In some embodiments, the closed-form expression based on the angle deviation is described by the following formula:

[0058] in, Indicates the signal direction angle, represents the inverse matrix of the covariance matrix of the noise difference vector, For phase.

[0059] Embodiment 3 This embodiment provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the steps in the multi-target rapid direction finding method based on single snapshot data as described in the first embodiment are implemented.

[0060] Embodiment 4 This embodiment provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the steps in the multi-target rapid direction finding method based on single snapshot data as described in the first embodiment are implemented.

[0061] Embodiment 5 This embodiment provides a computer program product or a computer program, which includes computer instructions, and the computer instructions are stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes the steps in the multi-target rapid direction finding method based on single snapshot data described in the first embodiment.

[0062] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of hardware embodiments, software embodiments, or embodiments combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) containing computer-usable program code.

[0063] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0064] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0065] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0066] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the above-mentioned methods. The storage medium can be a disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM), etc.

[0067] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A multi-target rapid direction finding method based on single snapshot data, characterized in that: include: Perform beamforming on all received single-snapshot signals, and search for K signals whose signal values ​​are greater than a set threshold after beamforming; divide the space where the K signals are located according to a certain angle grid interval to obtain a rough estimate of the direction angle of each signal; Based on the rough estimation of the direction angle of each signal, the amplitudes of K signals are calculated, K cycles are performed, and a correction is performed to obtain only the current signal to be estimated that is retained in each cycle; Based on the signal to be estimated in the current cycle, a secondary correction is performed using a closed-form expression based on the angle deviation to obtain the signal direction angle; The process of primary correction and secondary correction is iterated in a loop until the difference between the signal direction angles of two adjacent cycles of each signal is less than a preset threshold. The loop ends and the signal direction angles of all signals are output.

2. The multi-target rapid direction finding method based on single snapshot data according to claim 1, characterized in that: The space where the K signals are located is divided according to a certain angle grid interval to obtain a rough estimate of the direction angle of each signal; the method includes: dividing the space where the K signals are located according to a certain angle grid interval, locating the angle of each signal at the nearest discrete sampling grid point, and obtaining a rough estimate of the direction angle of each signal.

3. The multi-target rapid direction finding method based on single snapshot data according to claim 1, characterized in that: The method comprises: calculating the amplitudes of K signals based on the rough estimation of the direction angle of each signal, performing K cycles, performing a correction, and obtaining only the current signal to be estimated that is retained in each cycle; It is expressed by the following formula: in, Indicates k A signal is the current signal to be estimated; Indicates the signal received in each cycle, Indicates i The amplitude of a signal, Indicates i A rough estimate of the signal direction angle.

4. The multi-target rapid direction finding method based on single snapshot data according to claim 1, characterized in that: The signal to be estimated based on the current cycle is corrected twice using a closed-form expression based on an angle deviation to obtain a signal direction angle; the method comprises: conjugate multiplying the signal to be estimated in the current cycle received by two adjacent array elements, taking the phase after the multiplication, constructing a closed-form expression based on the angle deviation based on the multiplied phase and the covariance matrix of the noise difference vector of the two adjacent array elements, and solving to obtain the signal direction angle.

5. The multi-target rapid direction finding method based on single snapshot data according to claim 4, characterized in that: The conjugate multiplication of the signals to be estimated in the current cycle received by two adjacent array elements is expressed by the following formula: in, Indicates n The estimated signal of the current cycle received by +1 array element is the same as the n The signal to be estimated in the current cycle received by each array element is conjugate multiplied to form a new value. Indicates k The amplitude of a signal, is the position difference between two adjacent array elements, is the unknown angle of the incoming wave direction of the kth signal to be estimated, is the noise difference between two adjacent array elements.

6. The multi-target rapid direction finding method based on single snapshot data according to claim 5, characterized in that: The closed-form expression based on the angle deviation is described by the following formula: in, Indicates the signal direction angle, represents the inverse matrix of the covariance matrix of the noise difference vector, For phase.

7. A multi-target rapid direction finding system based on single snapshot data, characterized in that: include: A rough estimation module is configured to: perform beamforming on all received single-snapshot received signals, and search for K signals whose signal values ​​are greater than a set threshold after beamforming; divide the space where the K signals are located according to a certain angle grid interval to obtain a rough estimate of the direction angle of each signal; A primary correction module is configured to: calculate the amplitudes of K signals based on a rough estimate of the direction angle of each signal, perform K cycles, perform a correction, and obtain only the current signal to be estimated that is retained in each cycle; A secondary correction module is configured to: perform secondary correction based on the signal to be estimated in the current cycle by using a closed-form expression based on the angle deviation to obtain a signal direction angle; The iterative loop and output module is configured to: iterate the process of primary correction and secondary correction until the difference between the signal direction angles of each signal in two adjacent cycles is less than a preset threshold, the loop ends, and the signal direction angles of all signals are output.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps in the multi-target rapid direction finding method based on single snapshot data are implemented as described in any one of claims 1 to 6.

9. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps in the multi-target rapid direction finding method based on single snapshot data are implemented as described in any one of claims 1 to 6.

10. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the steps in the multi-target rapid direction finding method based on single snapshot data are implemented as described in any one of claims 1 to 6.

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