Echo time-frequency map-based single-fan radar jamming quantification evaluation method and system

Abstract

This invention discloses a method and system for quantitative assessment of radar interference of a single wind turbine based on echo time-frequency maps. The method includes performing the same time-frequency feature extraction processing on a first echo signal and a second echo signal to obtain a time-frequency map of a pure wind turbine scenario and a time-frequency map of a target-wind turbine composite scenario. The first echo signal is generated based on the wind turbine's scattered echo. The second echo signal is generated based on the target echo signal and the wind turbine's scattered echo. Based on the time-frequency map of the pure wind turbine scenario and the time-frequency map of the target-wind turbine composite scenario, an energy difference distribution comparison calculation is performed to obtain an energy difference matrix. The matrix is ​​used to determine the proportion of time-frequency units in the target's influence area whose energy difference is greater than a preset energy decision threshold. This proportion is used as a quantitative assessment index for radar interference of a single wind turbine and output. Thus, even without actual measurement conditions, the radar interference effect of a single wind turbine can be quantitatively, interpretably, and repeatably assessed.

Description

Technical Field

[0001] This invention belongs to the field of radar detection and electromagnetic environment assessment technology, specifically relating to a method and system for quantitative assessment of radar interference in a single wind turbine based on echo time-frequency diagrams. Background Technology

[0002] With the rapid development of the new energy industry, the deployment of large wind turbine generators in coastal areas, mountainous regions, and radar coverage areas is constantly expanding. Wind turbine generators are typically characterized by large structural dimensions, numerous metal components, and continuously rotating blades. They exhibit strong scattering characteristics within the radar operating frequency band and introduce significant time-varying echoes and micro-Doppler effects during blade rotation.

[0003] In actual radar operation, a single wind turbine can generate significant clutter echoes in its range cell and adjacent Doppler cells, leading to increased background noise in radar reception, masking of real target echoes, reduced detection probability, and the potential generation of false points, increasing the false alarm probability, which in turn affects subsequent target detection, track association, and tracking processing.

[0004] Therefore, in the process of radar site selection, wind farm planning, and operation and maintenance of existing radar systems, it is of great engineering application value and practical need to conduct a quantitative and interpretable assessment of the radar interference that a single wind turbine may cause.

[0005] Existing assessment methods for the impact of wind turbines on radar mainly include the following categories: 1. Empirical criteria or geometric obstruction assessment methods: These methods typically rely on the distance and altitude relationship between the wind turbine and the radar, as well as the degree of line-of-sight obstruction, to qualitatively determine whether the wind turbine might affect the radar. These methods are simple to implement, but only consider geometric relationships and do not address the physical mechanisms of radar echoes.

[0006] 2. Statistical evaluation methods based on equivalent clutter power: Some techniques equate wind turbine echoes to fixed clutter sources and statistically analyze clutter power or spot density within the radar coverage area to estimate the impact of wind turbines on radar false alarm levels. However, these methods typically employ simplification assumptions and are difficult to reflect the time-varying characteristics caused by wind turbine blade rotation.

[0007] 3. Overall Scattering Assessment Method Based on Electromagnetic Simulation: This approach uses electromagnetic simulation software to model the wind turbine as a whole, calculates its radar cross section (RCS), and infers the degree of radar interference. While this method offers high accuracy, it is complex to model and computationally intensive, making it unsuitable for engineering assessments and rapid decision-making scenarios.

[0008] In summary, existing assessment methods for the impact of wind turbines on radar detection performance generally suffer from problems such as reliance on field measurements, difficulty in isolating the influence of a single wind turbine, lack of quantitative and unified indicators for assessment results, and unclear physical mechanisms. These methods are insufficient to meet the engineering requirements for quantitative assessment of the interference effects of a single wind turbine in wind power project demonstration, radar site selection, and system anti-interference design.

[0009] Therefore, how to provide a method that can quantitatively, interpretably, and repeatably evaluate the radar interference effect of a single wind turbine without actual measurement conditions has become an important issue. Summary of the Invention

[0010] To address the aforementioned problems in the existing technology, this invention provides a method and system for quantitative evaluation of radar interference in a single wind turbine based on echo time-frequency diagrams.

[0011] The technical problem to be solved by this invention is achieved through the following technical solution: In a first aspect, the present invention provides a method for quantitative assessment of radar interference in a single wind turbine based on echo time-frequency maps, the method comprising: The same time-frequency feature extraction processing operation is performed on the first echo signal and the second echo signal to obtain the time-frequency map of the pure wind turbine scene and the time-frequency map of the target-wind turbine composite scene; the first echo signal is generated based on the wind turbine scattered echo; the second echo signal is generated based on the target echo signal and the wind turbine scattered echo. Based on the time-frequency diagram of the pure wind turbine scenario and the time-frequency diagram of the target-wind turbine composite scenario, the energy difference distribution is compared and calculated to obtain the energy difference matrix; The energy difference matrix is ​​used to determine the proportion of time-frequency units in the target influence area whose energy difference is greater than a preset energy decision threshold. This proportion is then used as a quantitative evaluation index for single-wind turbine radar interference and output.

[0012] Secondly, the present invention provides a single-wind turbine radar interference quantification assessment system based on echo time-frequency diagrams, the single-wind turbine radar interference quantification assessment system comprising: The signal processing module performs the same time-frequency feature extraction processing on the first echo signal and the second echo signal to obtain a time-frequency map of the pure wind turbine scene and a time-frequency map of the target-wind turbine composite scene; the first echo signal is generated based on the wind turbine scattered echo; the second echo signal is generated based on the target echo signal and the wind turbine scattered echo. The echo comparison analysis module is used to perform energy difference distribution comparison calculations based on the time-frequency diagram of the pure wind turbine scenario and the time-frequency diagram of the target-wind turbine composite scenario, and obtain the energy difference matrix. The evaluation output module is used to determine the proportion of time-frequency units in the target influence area whose energy difference is greater than a preset energy decision threshold using the energy difference matrix, and outputs the proportion as a quantitative evaluation index of single wind turbine radar interference.

[0013] Thirdly, the present invention provides an electronic device, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; When the processor executes the computer program stored in the memory, it implements the steps described in any of the above-mentioned methods for quantitative evaluation of single-wind turbine radar interference based on echo time-frequency diagrams.

[0014] Fourthly, the present invention provides a computer-readable storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the steps described in any of the above-mentioned methods for quantitative evaluation of single-wind turbine radar interference based on echo time-frequency diagrams.

[0015] This invention provides a method for quantitatively assessing single-wind turbine radar interference based on echo time-frequency maps. It extracts the same time-frequency features from a first echo signal generated from the wind turbine's scattered echo and a second echo signal generated from the target echo and the wind turbine's scattered echo, obtaining time-frequency maps of both the pure wind turbine scenario and the target-wind turbine composite scenario. Then, through energy difference matrix calculation and target influence area determination, the proportion of time-frequency units with energy differences exceeding a preset threshold is statistically analyzed and used as a quantitative assessment index for single-wind turbine radar interference. This index directly reflects the identifiability of target features against wind turbine clutter backgrounds, has clear physical meaning, and can provide a quantitative basis for radar site selection, wind farm planning, and interference suppression algorithm design. It can independently assess the interference level even without actual measurement data, and the assessment results are controllable and repeatable.

[0016] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating a method for quantitative evaluation of radar interference in a single wind turbine based on echo time-frequency diagrams, provided in an embodiment of the present invention. Figure 2 This is a schematic diagram of a single wind turbine radar echo scenario; Figure 3 This is a time-frequency diagram for a pure wind turbine scenario; Figure 4 This is a time-frequency diagram of a target-wind turbine composite scenario; Figure 5 This is a schematic diagram of the Doppler frequency component cell where the target is located; Figure 6 This is a schematic diagram of the structure of a single wind turbine radar interference quantification assessment system based on echo time-frequency diagrams provided in an embodiment of the present invention; Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0018] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0019] To address the shortcomings of existing single-wind-turbine radar interference assessment methods, such as reliance on field measurements, difficulty in isolating the influence of a single wind turbine, lack of unified quantitative indicators for assessment results, and unclear physical mechanisms, this invention provides a quantitative assessment method for single-wind-turbine radar interference based on echo time-frequency diagrams. (See [link to relevant documentation]). Figure 1 , Figure 1 This is a flowchart illustrating a method for quantitative assessment of radar interference in a single wind turbine based on echo time-frequency diagrams, provided by an embodiment of the present invention. The method specifically includes the following steps: Step S101: Perform the same time-frequency feature extraction processing operation on the first echo signal and the second echo signal to obtain the time-frequency map of the pure wind turbine scene and the time-frequency map of the target-wind turbine composite scene; the first echo signal is generated based on the wind turbine scattered echo; the second echo signal is generated based on the target echo signal and the wind turbine scattered echo.

[0020] In this embodiment of the invention, the wind turbine scattered echo includes static scattered echo and dynamic scattered echo; the static scattered echo is generated by the wind turbine tower structure, and the dynamic scattered echo is generated by the discretization of the rotating blades into multiple scattering centers.

[0021] Specifically, the wind turbine is divided into a static scattering section and a dynamic scattering section. The static scattering section includes fixed structures such as the tower; the dynamic scattering section includes rotating blades that rotate with the rotational speed. The rotating blades are discretized radially into multiple scattering centers. Based on the positional changes of the scattering centers and their radial velocity, the dynamic scattered echoes that vary with time are obtained.

[0022] The received echo from a general radar can be modeled as a linear superposition of multiple components, and its mathematical form can be summarized as follows: ; in, Indicates the target echo signal; This indicates a fan interference signal; Indicates a noise signal; The transmitted signal model is as follows: ; in, Represents the imaginary unit. Indicates frequency modulation. Indicates the pulse width; General echo signal It can then be expressed as: ; in, For the target RCS, For radar gain, For the target distance, For two-way propagation delay, It is the speed of light.

[0023] The slow time series corresponding to the general echo signal can be represented as: ; in, Indicates the echo signal; This indicates the slow-time sampling index, i.e., the pulse number; Indicates the pulse repetition interval; Indicates the target Doppler frequency; The Doppler frequency shift generated by a dynamic target is: ; in, Indicates radial velocity; Indicates the radar wavelength; In this embodiment of the invention, the echo component of the wind turbine is composed of multiple rotating blade scatterers and fixed structures such as the tower. Because the blades rotate over time, their radial velocity changes periodically, causing the echo Doppler frequency to modulate over time. This process manifests as Doppler broadening in the frequency domain and as a periodically changing micro-Doppler trajectory in the time-frequency domain. Each rotating blade rotates at an angle of... ; The dynamic component obtained by superimposing each echo is: ; in, This indicates the dynamic scattered echo of the wind turbine; This indicates the total number of rotating blades in the fan; Indicates the first Each rotating blade rotates with the angle of rotation. The changing real-time RCS value; Indicates radar gain; Indicates the radar distance. The distance between the rotating blades; Indicates the first The micro-Doppler frequency generated by the rotation of the rotating blade; Indicates the slow-time sampling index; Indicates the pulse repetition interval; Represents the imaginary unit; ; in, This indicates the radial velocity of the target.

[0024] In this embodiment of the invention, the static scattered echo of the wind turbine includes: ; in, Indicates static scattered echo; This represents the equivalent radar cross-section of the wind turbine tower and nacelle. Indicates radar gain; Represents the imaginary unit; Indicates the radar wavelength; Indicates the slow-time sampling index; This indicates the distance from the radar to the scattering center, specifically the distance from the radar to the static center of the wind turbine.

[0025] In this embodiment of the invention, the radar scattering characteristics of a wind turbine are decomposed into static scattered echoes generated by fixed structures such as the tower and dynamic scattered echoes generated by rotating blades. Furthermore, by discretizing the blades radially into multiple dynamic scattering centers and combining the blade rotation speed with geometric relationships, a wind turbine echo model with time-varying Doppler characteristics is constructed. This method accurately reflects the broadening and diffusion characteristics of wind turbine echoes in the radar range-Doppler domain, providing a physical basis for subsequent interference quantification.

[0026] Based on this, the first echo signal generated from the wind turbine's scattered echo includes: ; in, Indicates the first echo signal; Indicates noise. , Indicates variance.

[0027] The second echo signal, generated based on the target echo signal and the wind turbine scattered echo, includes: ; in, Indicates the second echo signal; This represents the target echo signal, which can also be obtained based on the acquisition process of a general echo signal.

[0028] In this embodiment of the invention, the same time-frequency feature extraction processing operation is performed on the first echo signal and the second echo signal to obtain a time-frequency map of the pure wind turbine scene and a time-frequency map of the target-wind turbine composite scene, including: The first echo signal and the second echo signal are respectively subjected to pulse compression processing to obtain the first pulse compressed signal and the second pulse compressed signal. For the first pulse compression signal and the second pulse compression signal, the distance unit with the largest amplitude is selected respectively, and the corresponding first slow time series and second slow time series are extracted from them. Time-frequency analysis was performed on the first and second slow time series to obtain their corresponding time-frequency energy distributions, which were used as time-frequency diagrams for the pure wind turbine scenario and the target-wind turbine composite scenario, respectively.

[0029] Mathematically, pulse compression is equivalent to convolving the received echo with the time-reversed conjugate of the transmitted signal. For LFM signals, this processing creates a sharp main lobe at the matching time, the width of which is determined by the signal bandwidth, thus significantly improving range resolution. Simultaneously, matched filtering also provides a processing gain proportional to the time-band product, making the target stand out more against a noisy background.

[0030] The following will explain how to extract the time-frequency diagram from the echo signal: First, matched filtering can be expressed as: ; in, This represents the impulse response of the matched filter; express The complex conjugate, This represents the time-reversed form of the transmitted signal used to construct the impulse response of the matched filter; Indicates the pulse width; Indicates a time index; By using matched filtering, the pulse compression signal is obtained: ; Among them, when When it is the first echo signal, the pulse compression signal is the first pulse compression signal. When it is the second echo signal, the pulse compression signal is the second pulse compression signal; Represents the integral variable; For the first pulse compression signal and the second pulse compression signal, the maximum amplitude distance unit is: ; in, Indicates the index of the cell with the maximum amplitude; Indicates the first pulse echo, the second pulse echo. Echo values ​​per distance cell; The operator's function is to extract the index number of the distance cell that maximizes the energy.

[0031] when This indicates that under the first pulse echo in the first pulse compression signal, the... When the echo value of a distance cell is... Indicates the maximum distance cell index of the amplitude of the first pulse compressed signal; when This indicates the time of the first pulse in the second pulse compression signal. When the echo value of a distance cell is... This indicates the maximum distance cell index of the second pulse compression signal.

[0032] Based on the first pulse compression signal and the maximum amplitude distance unit of the first pulse compression signal, respectively, the corresponding first slow time series and second slow time series are extracted, including: ; in, Represents a slow time series; Indicates the first At each pulse moment, the maximum amplitude of the locked distance unit position The complex echo value at that location.

[0033] Similarly, when Indicates the first pulse compression signal in the 1st... At each pulse moment, the maximum amplitude of the locked distance unit position When the complex echo value is at that point, For the first slowest time series; when Indicates the second pulse compression signal in the 1st... At each pulse moment, the maximum amplitude of the locked distance unit position When the complex echo value is at that point, This is the second slowest time series.

[0034] In this embodiment of the invention, the first slow time series and the second slow time series are processed by short-time Fourier transform to obtain their corresponding time-frequency energy distributions, which are respectively used as time-frequency diagrams of the pure wind turbine scenario and the target-wind turbine composite scenario.

[0035] Step S102: Based on the time-frequency diagram of the pure wind turbine scenario and the time-frequency diagram of the target-wind turbine composite scenario, perform energy difference distribution comparison calculation to obtain the energy difference matrix.

[0036] By comparing the energy difference between the pure wind turbine echo and the target-wind turbine composite echo in the time-frequency domain, the changes in target features against the background of wind turbine clutter can be obtained, the target influence area can be determined, and the degree of energy submersion of the target features against the background of wind turbine clutter can be calculated. Specifically, the influence area of ​​the target echo signal in the time-frequency domain is first determined based on the target motion parameters. This area corresponds to the set of time-frequency cells within the target Doppler frequency and its neighborhood.

[0037] In this embodiment of the invention, an energy difference distribution comparison calculation is performed based on the time-frequency diagram of a pure wind turbine scenario and the time-frequency diagram of a target-wind turbine composite scenario to obtain an energy difference matrix, including: Determine the target's influence region in the time-frequency domain based on the target's motion parameters; Calculate the energy difference matrix between the time-frequency diagram of the target-wind turbine composite scenario and the time-frequency diagram of the pure wind turbine scenario within the influence area.

[0038] The calculation methods for the energy difference matrix include: ; in, Represents the energy difference matrix; This represents the energy distribution in the time-frequency diagram of a pure wind turbine scenario. The energy distribution is represented by the time-frequency diagram of the target-wind turbine composite scenario.

[0039] Step S103: Use the energy difference matrix to determine the proportion of time-frequency units in the target influence area whose energy difference is greater than the preset energy decision threshold, and use the proportion as a quantitative evaluation index for single wind turbine radar interference and output it.

[0040] In this embodiment of the invention, determining the proportion of time-frequency units in the target influence region whose energy difference is greater than a preset energy decision threshold using an energy difference matrix includes: ; in, This represents the percentage of time-frequency units where the energy difference is greater than a preset energy decision threshold. This indicates the total number of time-frequency cells within the target's influence area; This indicates the number of time-frequency units where the energy difference is greater than a preset energy decision threshold; This indicates the preset energy decision threshold; It can be adaptively set according to different radar system parameters, wind turbine operating status and target signal-to-noise ratio.

[0041] Finally, the proportion of time-frequency units with energy differences greater than the preset energy decision threshold is used as the quantitative evaluation index for single wind turbine radar interference and output. This index can be used to characterize the degree of influence of a single wind turbine on the detectability of radar targets.

[0042] The quantitative evaluation index of radar interference of a single wind turbine can intuitively reflect the degree of impact of a single wind turbine on the radar target detection capability. Its physical meaning is the proportion of time-frequency units in which the target features remain effectively identifiable under the background of wind turbine interference.

[0043] When the value of this index is large, it indicates that the target echo signal still has good distinguishability in the background of wind turbine interference, and the wind turbine has little impact on radar detection performance; when the value of this index is small, it indicates that the wind turbine echo has a high degree of obscuring of the target features, and has a more significant impact on radar target detection performance.

[0044] In this embodiment of the invention, the same time-frequency features are extracted from the first echo signal generated based on the wind turbine's scattered echo and the second echo signal generated based on the target echo signal and the wind turbine's scattered echo, resulting in a time-frequency map of the pure wind turbine scene and a time-frequency map of the target-wind turbine composite scene. Then, through energy difference matrix calculation and target influence area determination, the proportion of time-frequency units with energy differences greater than a preset threshold is statistically analyzed and used as a quantitative evaluation index for single-wind turbine radar interference. This index directly reflects the identifiability of target features against the background of wind turbine clutter, has a clear physical meaning, and can provide a quantitative basis for radar site selection, wind farm planning, and interference suppression algorithm design. It can independently evaluate the interference level even without actual measurement data, and the evaluation results are controllable and repeatable.

[0045] The simulation experiment of a single wind turbine radar interference quantification assessment method based on echo time-frequency diagrams provided by the embodiments of the present invention is as follows: First, a single wind turbine radar echo simulation scenario was established, and the radar system parameters, wind turbine parameters, and target parameters were configured. The radar system performed echo acquisition and processing according to the preset pulse repetition frequency, pulse number, and frame number. Subsequently, under the same radar parameter conditions, the following two types of echo data were generated: (1) Pure wind turbine echo data containing only wind turbine scattered echoes; (2) Composite echo data including the superposition of the target echo signal and the wind turbine scattered echo.

[0046] Taking a scenario where the radar carrier frequency is 1GHz, the wind turbine is 1500m horizontally away from the radar, and the target is flying radially away from the radar directly above the wind turbine, the scenario is illustrated as follows: Figure 2 As shown, Figure 2 This is a schematic diagram of a single wind turbine radar echo scenario.

[0047] After each frame of echo data is generated, the pure wind turbine echo is first subjected to pulse compression processing to obtain the range compression result, and the range cell with the highest energy in the range dimension is selected as the analysis range gate. Then, the slow time series signal corresponding to the range gate is extracted and accumulated in multiple frames of data to form a slow time data matrix of pure wind turbine echo.

[0048] Based on this, the composite echo data after superimposing the target echo signal and the wind turbine echo is subjected to the same pulse compression processing. The same distance unit as the pure wind turbine scenario is selected to extract the corresponding slow time series signal and superimpose it in the time dimension to form a slow time data matrix of target-wind turbine composite echo.

[0049] Subsequently, short-time Fourier transforms were performed on the two types of slow-time data to obtain the corresponding time-frequency energy distributions, see [link to relevant documentation]. Figure 3 and Figure 4 , Figure 3 This is the time-frequency diagram for a pure wind turbine scenario, specifically the time-frequency diagram for the first scenario. Figure 4 This is the time-frequency diagram of the target-wind turbine composite scenario, i.e., the second scenario time-frequency diagram. By comparing the energy difference between the pure wind turbine echo and the target-wind turbine composite echo in the time-frequency domain, we can obtain the changes in target characteristics against the background of wind turbine clutter.

[0050] See Figure 5 , Figure 5 This is a schematic diagram of the Doppler frequency component cells where the target is located. Threshold determination statistics are performed only on the time-frequency cells within the target's influence region. The time-frequency cells affected by the target's uniform motion are as follows: Figure 5 As shown in the blue area, a time-frequency energy difference matrix is ​​constructed, and the proportion of cells that meet the conditions is statistically analyzed. In the simulation example above, by statistically calculating the time-frequency energy difference within the target's influence region, the interference quantization index R = 0.2969 is obtained.

[0051] The results show that within the time-frequency influence area where the target echo signal may occur, only about 29.69% of the time-frequency cells have an energy difference exceeding the set threshold, meaning that the target echo signal characteristics in these cells are somewhat identifiable relative to the wind turbine clutter; while in the remaining about 70.31% of the time-frequency cells, the target echo energy is significantly affected by the wind turbine echo or is submerged by the wind turbine clutter.

[0052] In other words, under the current radar parameters and wind turbine operating conditions, the echo generated by the wind turbine has already caused significant interference to the target echo feature region, making the target features detectable only in some time-frequency units.

[0053] Therefore, the single wind turbine radar interference quantitative evaluation index R can intuitively reflect the degree of influence of a single wind turbine on the radar target detection capability. Its physical meaning is the proportion of time-frequency units in which the target features remain effectively identifiable under the background of wind turbine interference.

[0054] When the value of this index is large, it indicates that the target echo signal still has good distinguishability in the background of wind turbine interference, and the wind turbine has little impact on radar detection performance; when the value of this index is small, it indicates that the wind turbine echo has a high degree of obscuring of the target features, and has a more significant impact on radar target detection performance.

[0055] Based on the same inventive concept, embodiments of the present invention also provide a single-wind turbine radar interference quantification and evaluation system based on echo time-frequency diagrams, see [link to relevant documentation]. Figure 6 , Figure 6 This is a schematic diagram of a single-wind turbine radar interference quantification assessment system based on echo time-frequency diagrams provided in an embodiment of the present invention. The single-wind turbine radar interference quantification assessment system includes: Signal processing module 601 is used to perform the same time-frequency feature extraction processing operation on the first echo signal and the second echo signal to obtain a time-frequency map of the pure wind turbine scene and a time-frequency map of the target-wind turbine composite scene; the first echo signal is generated based on the wind turbine scattered echo; the second echo signal is generated based on the target echo signal and the wind turbine scattered echo. The echo comparison analysis module 602 is used to perform energy difference distribution comparison calculation based on the time-frequency diagram of the pure wind turbine scenario and the time-frequency diagram of the target-wind turbine composite scenario to obtain the energy difference matrix; The evaluation output module 603 is used to determine the proportion of time-frequency units in the target influence area whose energy difference is greater than a preset energy decision threshold using the energy difference matrix, and outputs the proportion as a quantitative evaluation index of single wind turbine radar interference.

[0056] In this embodiment of the invention, the same time-frequency features are extracted from the first echo signal generated based on the wind turbine's scattered echo and the second echo signal generated based on the target echo signal and the wind turbine's scattered echo, resulting in a time-frequency map of the pure wind turbine scene and a time-frequency map of the target-wind turbine composite scene. Then, through energy difference matrix calculation and target influence area determination, the proportion of time-frequency units with energy differences greater than a preset threshold is statistically analyzed and used as a quantitative evaluation index for single-wind turbine radar interference. This index directly reflects the identifiability of target features against the background of wind turbine clutter, has a clear physical meaning, and can provide a quantitative basis for radar site selection, wind farm planning, and interference suppression algorithm design. It can independently evaluate the interference level even without actual measurement data, and the evaluation results are controllable and repeatable.

[0057] This invention also provides an electronic device, such as... Figure 7As shown, it includes a processor 701, a communication interface 702, a memory 703, and a communication bus 704, wherein the processor 701, the communication interface 702, and the memory 703 communicate with each other through the communication bus 704. Memory 703 is used to store computer programs; When the processor 701 executes the program stored in the memory 703, it implements the method steps of any of the above-mentioned methods for quantitative evaluation of single wind turbine radar interference based on echo time-frequency diagrams.

[0058] The communication bus mentioned in the above electronic devices can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into address bus, data bus, control bus, etc. For ease of representation, only one thick line is used in the diagram, but this does not indicate that there is only one bus or one type of bus.

[0059] The communication interface is used for communication between the aforementioned electronic devices and other devices.

[0060] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0061] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be 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, or discrete hardware components.

[0062] The present invention also provides a computer-readable storage medium. A computer program is stored in the computer-readable storage medium, and when executed by a processor, the computer program implements the method steps of any of the above-described methods for quantitative assessment of single-wind turbine radar interference based on echo time-frequency diagrams.

[0063] Optionally, the computer-readable storage medium may be non-volatile memory (NVM), such as at least one disk storage device.

[0064] Optionally, the aforementioned computer-readable storage medium may also be at least one storage device located remotely from the aforementioned processor.

[0065] In another embodiment of the present invention, a computer program product containing instructions is also provided, which, when run on a computer, causes the computer to execute the steps of the method described in any of the above-described methods for quantitative evaluation of single-wind turbine radar interference based on echo time-frequency diagrams.

[0066] It should be noted that the terms "first," "second," etc., are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the invention.

[0067] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0068] Although the invention has been described herein in conjunction with various embodiments, those skilled in the art will understand and implement other variations of the disclosed embodiments by reviewing the accompanying drawings and the disclosure in carrying out the claimed invention. In the description of the invention, the word "comprising" does not exclude other components or steps, "a" or "an" does not exclude a plurality, and "a plurality" means two or more, unless otherwise explicitly specified. Furthermore, while different embodiments may describe certain measures, this does not mean that these measures cannot be combined to produce good results.

[0069] The method provided in this invention can be applied to electronic devices. Specifically, the electronic device can be a desktop computer, a portable computer, a smart mobile terminal, a server, etc. No limitation is made herein; any electronic device that can implement this invention falls within the protection scope of this invention.

[0070] For the embodiments of the device / electronic device / storage medium, since they are basically similar to the method embodiments, the description is relatively simple, and relevant parts can be referred to in the description of the method embodiments.

[0071] It should be noted that the device, electronic device and storage medium in the embodiments of the present invention are respectively the device, electronic device and storage medium for applying the above-mentioned method for quantitative evaluation of single wind turbine radar interference based on echo time-frequency diagram. Therefore, all embodiments of the above-mentioned method for quantitative evaluation of single wind turbine radar interference based on echo time-frequency diagram are applicable to the device, electronic device and storage medium, and can achieve the same or similar beneficial effects.

[0072] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A method for quantitative assessment of radar interference in a single wind turbine based on echo time-frequency diagrams, characterized in that, The single-wind-turbine radar interference quantitative assessment method includes: The same time-frequency feature extraction processing operation is performed on the first echo signal and the second echo signal to obtain the time-frequency map of the pure wind turbine scene and the time-frequency map of the target-wind turbine composite scene; the first echo signal is generated based on the wind turbine scattered echo; the second echo signal is generated based on the target echo signal and the wind turbine scattered echo. Based on the time-frequency diagram of the pure wind turbine scenario and the time-frequency diagram of the target-wind turbine composite scenario, the energy difference distribution is compared and calculated to obtain the energy difference matrix; The energy difference matrix is ​​used to determine the proportion of time-frequency units in the target influence area whose energy difference is greater than a preset energy decision threshold. This proportion is then used as a quantitative evaluation index for single-wind turbine radar interference and output.

2. The method for quantitative assessment of radar interference in a single wind turbine according to claim 1, characterized in that, The wind turbine scattered echo includes static scattered echo and dynamic scattered echo; the static scattered echo is generated by the wind turbine tower structure, and the dynamic scattered echo is generated by the discretization of the rotating blades into multiple scattering centers.

3. The method for quantitative assessment of radar interference in a single wind turbine according to claim 2, characterized in that, The static scattered echo includes: ； in, This refers to the static scattered echo; This represents the equivalent radar cross-section of the wind turbine tower and nacelle. This indicates the distance from the radar to the scattering center; Indicates radar gain; Represents the imaginary unit; Indicates the radar wavelength; This indicates the slow-time sampling index.

4. The method for quantitative assessment of radar interference in a single wind turbine according to claim 2, characterized in that, The dynamic scattered echo includes: ； in, This refers to the dynamic scattered echo; This indicates the total number of rotating blades in the fan; Indicates the first Each rotating blade rotates with the angle of rotation. The changing real-time RCS value; Indicates radar gain; Indicates the radar distance. The distance between the rotating blades; Indicates the first The micro-Doppler frequency generated by the rotation of the rotating blade; Indicates the slow-time sampling index; Indicates the pulse repetition interval; It represents the imaginary unit.

5. The method for quantitative assessment of radar interference in a single wind turbine according to claim 1, characterized in that, The same time-frequency feature extraction processing is performed on the first and second echo signals to obtain the time-frequency map of the pure wind turbine scene and the time-frequency map of the target-wind turbine composite scene, including: The first echo signal and the second echo signal are respectively subjected to pulse compression processing to obtain the first pulse compressed signal and the second pulse compressed signal. For the first pulse compression signal and the second pulse compression signal, select the distance unit with the largest amplitude respectively and extract the corresponding first slow time series and second slow time series from them; Time-frequency analysis was performed on the first slow time series and the second slow time series respectively to obtain their corresponding time-frequency energy distributions, which were used as time-frequency diagrams for the pure wind turbine scenario and the target-wind turbine composite scenario, respectively.

6. The method for quantitative assessment of radar interference in a single wind turbine according to claim 1, characterized in that, Based on the time-frequency diagrams of the pure wind turbine scenario and the target-wind turbine composite scenario, an energy difference distribution comparison calculation is performed to obtain an energy difference matrix, including: Determine the target's influence region in the time-frequency domain based on the target's motion parameters; Calculate the energy difference matrix between the time-frequency diagram of the target-wind turbine composite scenario and the time-frequency diagram of the pure wind turbine scenario within the influence area.

7. A single-wind turbine radar interference quantification assessment system based on echo time-frequency diagrams, characterized in that, The single-wind turbine radar interference quantitative assessment system includes: The signal processing module performs the same time-frequency feature extraction processing on the first echo signal and the second echo signal to obtain a time-frequency map of the pure wind turbine scene and a time-frequency map of the target-wind turbine composite scene; the first echo signal is generated based on the wind turbine scattered echo; the second echo signal is generated based on the target echo signal and the wind turbine scattered echo. The echo comparison analysis module is used to perform energy difference distribution comparison calculations based on the time-frequency diagram of the pure wind turbine scenario and the time-frequency diagram of the target-wind turbine composite scenario, and obtain the energy difference matrix. The evaluation output module is used to determine the proportion of time-frequency units in the target influence area whose energy difference is greater than a preset energy decision threshold using the energy difference matrix, and outputs the proportion as a quantitative evaluation index of single wind turbine radar interference.

8. The single-wind turbine radar interference quantification assessment system according to claim 7, characterized in that, The wind turbine scattered echo includes static scattered echo and dynamic scattered echo; the static scattered echo is generated by the wind turbine tower structure, and the dynamic scattered echo is generated by the discretization of the rotating blades into multiple scattering centers.

9. An electronic device, characterized in that, It includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; When a processor executes a computer program stored in a memory, it implements the single-wind turbine radar interference quantification assessment method based on echo time-frequency diagrams as described in any one of claims 1-6.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the single-wind turbine radar interference quantification assessment method based on echo time-frequency diagrams as described in any one of claims 1-6.

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