Target rotating part imaging method and device based on micro Doppler phase compensation

Abstract

The invention relates to a target rotating part imaging method and device based on micro Doppler phase compensation. The method comprises the following steps: processing an integral echo pulse signal of a target based on a micro-Doppler technology to obtain prior information of a target rotating part and a separated echo pulse signal of the target rotating part; and calculating a translation phase compensation coefficient of the target rotating part according to the prior information. And in the coherent processing interval, according to the echo pulse signal, calculating a rotation phase compensation coefficient of the echo pulse of the scattering point of the target rotating part from the angle channel where the coherent processing starting moment is located. And according to the translation phase compensation coefficient and the rotation phase compensation coefficient, obtaining an echo accumulation result of all scattering points of the target rotation component, and according to the echo accumulation result, calculating an imaging result of the angular domain space. By adopting the method, the angular domain spatial distribution image of the low-altitude rotor target rotating part can be obtained, so that the target feature extraction precision is improved, and the classification and recognition capability of a radar on a low-altitude target is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of radar target imaging, and particularly to a method and device for imaging a target rotating component based on micro-Doppler phase compensation. Background Art

[0002] The rapid development of low-altitude aircraft has brought huge technical challenges to the field of low-altitude target surveillance. How to detect and identify low-altitude aircraft targets in a timely and reliable manner under complex terrain background conditions is a key problem that needs to be solved urgently. Imaging the target to obtain information such as the size, shape, and attitude of the target is an effective means for target classification and recognition. However, affected by the micro-Doppler modulation of the rotating components on the low-altitude aircraft on the radar signal, traditional ISAR imaging methods often have difficulty obtaining an effective image of the target. First, the micro-Doppler modulation affects the accuracy of motion compensation and the imaging quality. Second, the Doppler bandwidth broadening caused by the micro-Doppler modulation, after azimuth compression, the micro-Doppler modulation part cannot be focused, forming azimuth interference strips. Therefore, the micro-Doppler modulation brought by the rotating components is often regarded as an adverse factor in ISAR imaging and is removed. Summary of the Invention

[0003] Based on this, it is necessary to provide a method and device for imaging a target rotating component based on micro-Doppler phase compensation that can obtain the distribution image of the signal energy of the target rotating blade on the rotation circumference for the above technical problems.

[0004] A method for imaging a target rotating component based on micro-Doppler phase compensation, the method comprising: Processing the target overall echo pulse signal based on micro-Doppler technology to obtain the prior information of the target rotating component and the separated echo pulse signal of the rotating component.

[0005] Calculating the translational phase compensation coefficient of the target rotating component according to the prior information.

[0006] Within the coherent processing interval, calculating the rotational phase compensation coefficient of the echo pulse of the scattering point of the target rotating component with respect to the angular channel where the starting coherent processing moment is located according to the echo pulse signal of the target rotating component.

[0007] Obtaining the echo accumulation result of all scattering points of the rotating component according to the translational phase compensation coefficient and the rotational phase compensation coefficient, and calculating the imaging result in the angular domain space according to the echo accumulation result.

[0008] A device for imaging a target rotating component based on micro-Doppler phase compensation, the device comprising: A spectrum feature processing module, configured to process the target overall echo pulse signal based on micro-Doppler technology to obtain the prior information of the target rotating component and the separated echo pulse signal of the target rotating component.

[0009] A translational phase compensation module, which is used to calculate the translational phase compensation coefficient of the target rotating component according to the prior information.

[0010] A rotational phase compensation module, which is used to calculate the rotational phase compensation coefficient of the echo pulse of the scattering point of the target rotating component in the angular channel where the echo pulse at the starting coherent processing moment is located according to the echo pulse signal of the target rotating component within the coherent processing interval.

[0011] An imaging module, which is used to obtain the echo accumulation result of all scattering points of the target rotating component according to the translational phase compensation coefficient and the rotational phase compensation coefficient, and calculate the imaging result in the angular domain space according to the echo accumulation result.

[0012] For the above-mentioned imaging method and device of the target rotating component based on micro-Doppler phase compensation, first, the prior information of the target rotating component is extracted through micro-Doppler spectrum analysis, including key parameters such as rotational speed and axis position, and a micro-motion model of the rotating component is established. On this basis, the rotation plane of the rotating component is divided into several angular channels by angle, and a two-stage phase compensation strategy is adopted to complete the coherent compensation of the echo signal of the rotating component: the first stage calculates the phase compensation coefficient of the overall translation of the target according to the prior information, and eliminates the phase change of the echo of the rotating component caused by the main body movement of the target by compensating the Doppler frequency shift caused by the translation; the second stage calculates the rotational phase compensation coefficient within the coherent processing interval in combination with the unique motion characteristics of the target rotating component, and this coefficient accurately reflects the phase change of the echo of each scattering point of the rotating component in a certain angular channel. After two-stage phase compensation, the phase difference between the echo pulses of each scattering point of the rotating component caused by translation and rotation is effectively eliminated. Finally, after accumulating the energies of each pulse according to the angular channel, the imaging result of the rotating component in the angular domain space can be obtained. Aiming at the problem that the Doppler bandwidth broadening caused by micro-motion makes the traditional ISAR imaging method unable to effectively focus in the azimuth direction, thereby reducing the feature extraction and recognition ability of the rotating component, this method innovatively proposes a method of imaging in the angular domain space. By compensating the fixed phase difference caused by the position difference of the scattering points of the rotating component, and the phase change between the echo pulses of the echo signals of each scattering point caused by the rotational motion, after the energy coherent accumulation processing, finally, a clear distribution image of the signal energy of the target rotating component on the rotation circumference is obtained. The image obtained by this method can support the extraction of physical characteristics such as the size and quantity of the target rotating component, significantly improve the feature estimation accuracy of low-altitude rotor targets, and enhance the radar's classification and recognition ability for low-altitude targets. Description of the Drawings

[0013] Figure 1 It is an application scenario diagram of the imaging method of the target rotating component based on micro-Doppler phase compensation in an embodiment; Figure 2Schematic flowchart of the imaging method for a target rotating component based on micro-Doppler phase compensation in an embodiment; Figure 3 Top view of the motion state decomposition of the rotor blade of an unmanned aerial vehicle / helicopter in an embodiment; Figure 4 Schematic diagram of the division of the scattering points and the rotation circumferential angle channels of the blade in an embodiment; Figure 5 Structural block diagram of the imaging device for a target rotating component based on micro-Doppler phase compensation in an embodiment. Detailed implementation manners

[0014] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0015] The imaging method for a target rotating component based on micro-Doppler phase compensation provided by the present invention can be applied to the position of the rotor target and the radar as shown in Figure 1 . Schematic diagram of the positions of the target and the radar, the coordinate system is a space-fixed coordinate system, and the origin is the position where the radar is located. The coordinate system is a target-fixed coordinate system, and its origin is also the rotation center of the rotor blade. The rotating blade rotates around the axis at an angular velocity (rotation frequency is ). At the starting moment of the rotor motion, the initial azimuth angle and elevation angle of the origin of the target coordinate system in the space-fixed coordinate system are and respectively, and its initial distance to the origin of the space-fixed coordinate system is .

[0016] Figure 2 In an embodiment, as shown in Figure 1 , an imaging method for a target rotating component based on micro-Doppler phase compensation is provided. Taking the application of this method to the single-rotor target in as an example, the method includes the following steps: Step 202: Process the overall echo pulse signal of the target based on micro-Doppler technology to obtain the prior information of the target rotating component and the separated echo pulse signal of the target rotating component.

[0017] Step 204: Calculate the translational phase compensation coefficient of the target rotating component according to the prior information.

[0018] Step 206: Within the coherent processing interval, calculate the rotational phase compensation coefficient of the echo pulse of the scattering point of the target rotating component with respect to the echo pulse in the angular channel where the starting coherent processing moment is located, based on the echo pulse signal of the target rotating component.

[0019] Step 208: Obtain the echo accumulation result of all scattering points of the target rotating component according to the translational phase compensation coefficient and the rotational phase compensation coefficient, and calculate the imaging result in the angular domain space based on the echo accumulation result.

[0020] In the above imaging method of the target rotating component based on micro-Doppler phase compensation, first, extract the prior information of the target rotating component through micro-Doppler spectrum analysis, including key parameters such as rotational speed and axis position, and establish a micro-motion model of the rotating component. On this basis, divide the rotation plane of the rotating component into several angular channels by angle, and adopt a two-stage phase compensation strategy to complete the coherent compensation of the echo signal of the rotating component: the first stage calculates the phase compensation coefficient of the overall translation of the target based on the prior information, and eliminates the phase change of the echo of the rotating component caused by the main body motion of the target by compensating the Doppler frequency shift caused by translation; the second stage calculates the rotational phase compensation coefficient within the coherent processing interval in combination with the unique motion characteristics of the target rotating component, and this coefficient accurately reflects the phase change of the echo of each scattering point of the rotating component in a certain angular channel. After two-stage phase compensation, the phase difference between the echo pulses of each scattering point of the rotating component caused by translation and rotation is effectively eliminated. Finally, after accumulating the energy of each pulse according to the angular channel, the imaging result of the rotating component in the angular domain space can be obtained. Aiming at the problem that the traditional ISAR imaging method cannot effectively focus in the azimuth direction due to the Doppler bandwidth broadening caused by micro-motion, which further reduces the feature extraction and recognition ability of the rotating component, this method innovatively proposes a method of imaging in the angular domain space. By compensating the fixed phase difference caused by the position difference of the scattering points of the rotating component, and the phase change between the echo pulses of the echo signals of each scattering point due to rotational motion, after energy coherent accumulation processing, finally, a clear distribution image of the signal energy of the target rotating component on the rotation circumference is obtained. The image obtained by this method can support the extraction of physical characteristics such as the size and quantity of the target rotating component, significantly improve the feature estimation accuracy of low-altitude rotor targets, and enhance the radar's classification and recognition ability for low-altitude targets.

[0021] In one embodiment, perform pulse compression processing on the overall pulse sequence of the target received by the radar based on micro-Doppler technology, analyze the micro-Doppler spectrum characteristics of the target, obtain the prior information of the rotational speed of the target rotating component, and separate the echo pulse signal of the target main body to obtain the separated echo signal of the target rotating component.

[0022] In one embodiment, the prior information includes: the wavelength, bandwidth, linear frequency modulation rate, pulse duration of the radar transmitted signal, the target motion speed, the distance from the center point of the target rotating component to the radar, and the rotational angular velocity of the target rotating component.

[0023] Separate the echo signal components of the target object according to the prior information, and calculate the echo pulse compression results of the scattering points on each blade of the target rotating component: ; Among them, is the distance from the scattering point on the target rotating component to the radar, is the signal after the echo pulse compression of the scattering point, is the bandwidth of the radar transmitted signal, is the imaginary unit, is the pulse duration, is the radial distance from the center of the target rotating component to the radar, is the wavelength of the radar transmitted signal, is the Doppler frequency generated by the translational motion of the target object, is the speed of light, is the amplitude of the echo pulse compression result of the rotating component, is the fixed initial phase of the scattering point, is the translational Doppler modulation phase of the echo signal of the scattering point, is the rotational modulation phase of the echo signal of the scattering point, is the distance from the scattering point to the center of rotation, is the initial elevation angle of the center of the target rotating component in the space-fixed coordinate system, is the angular velocity of the blade rotation, is the angle between the blade and the positive x-axis of the space-fixed coordinate system at the initial moment. Obtain the translational phase compensation coefficient of the scattering points on each angular channel in the target rotating component according to the echo signal of the scattering points: ; Among them, is the translational phase compensation coefficient, is the Doppler frequency generated by the translational motion of the target object, is the total number of angular channels, is the pulse duration.

[0024] In one embodiment, within the coherent processing interval, calculate the rotational phase compensation coefficient of the echo pulse of the scattering point of the target rotating component from the angular channel where the starting coherent processing moment is located according to the echo pulse signal of the target rotating component: ; Among them, is the rotational phase compensation coefficient of the th echo pulse signal of the target rotating component, is the serial number of the scattering point on the blade, is the echo pulse serial number, is the interval between adjacent scattering points, is the serial number of the angular channel, is the interval between adjacent angular channels, is the pulse repetition period, is the total number of echo pulse signals of the target rotating component within the coherent processing interval.

[0025] In one embodiment, according to the translational phase compensation coefficient and the rotational phase compensation coefficient, the echo accumulation result of all scattering points in the current angular channel; ; Wherein, is the echo accumulation result of the th angular channel, is the translational phase compensation coefficient of the th echo pulse signal, is the rotational phase compensation coefficient of the th echo pulse signal of the target rotating component, is the pulse compression result of the th echo pulse of the target rotating component.

[0026] In one embodiment, traverse and calculate the echo accumulation result after accumulating all angular channels to obtain the target echo signal, and calculate the imaging result of the blade of each angular channel on the rotation circumferential angle of the target rotating component according to the target echo signal: ; Wherein, is the imaging result, is the echo accumulation result of the th angular channel, is the pulse repetition period, is the total number of scattering points.

[0027] In one embodiment, as Figure 3 shown, assume there is a single-rotor target in the far field of the radar. The rotor has blades. The whole rotor is in translational motion, and at the same time, all blades on the rotor rotate periodically around the target center point. Build a model for the radar scattering echo of the rotor target. According to the analysis of the figure, the motion of the rotor blade can be equivalent to the combination of translational motion (translation) and rotational motion (rotation). To simplify the analysis, assume that the rotor rotates on a plane parallel to the horizontal plane. At this time, the pitch and azimuth angles of the rotor blade relative to the radar are both , that is, . At this time, a certain scattering point on the blade reaches point after translational motion, and then with an angular velocity Rotate around the axis to point . It is positive when rotating counterclockwise and negative when rotating clockwise. Among them, represents the radial velocity of the target translational motion. The velocity is positive when moving away from the radar and negative when approaching the radar; represents the scatterer to the distance from the center of rotation; is the angle between the blade and the positive axis at the initial moment, then the rotation angle at the moment of . Therefore, the distance from the radar to the point scatterer can be defined as: (1) Since under the far-field condition, , so equation (1) can be approximated as: (2) When the pitch angle of the rotor blade is not zero, the above formula can be corrected as: (3) Assume that the LFM signal (linear frequency modulation signal) transmitted by the radar is expressed as: (4) (5) Among them is the pulse duration, is the center frequency, is the time variable, is the linear frequency modulation rate. For the convenience of analysis, without loss of generality, it is assumed here that the amplitudes of the transmitted signal and the scatterer echo signal are both 1. Then the radar echo signal of the scatterer can be expressed as: (6) Among them is the speed of light. It can be seen that the phase of the scatterer echo signal is very sensitive to the distance change of the target.

[0028] After the echo signal passes through mixing, quadrature demodulation, and pulse compression processing, the obtained scatterer echo signal is (7) Among them is the radar transmission signal bandwidth. Substituting equation (3) into equation (7), the echo signal of the blade scatterer can be obtained as: (8) Among them is the fixed initial phase, is the radar emission signal wavelength, denoted as is the fixed phase term; is the Doppler modulation phase caused by the overall translation of the target, called the translation phase, , denoted as is the translation phase term; is the rotation modulation phase of the echo of the blade scattering point, called the rotation phase, denoted as is the rotation phase term.

[0029] It should be noted that the radar echo phase of each scattering point on the target rotor blade is modulated by the translation of the target body and the rotation of the blade. Among them, the translation phase and the rotation phase cause a phase difference related to the motion in each echo pulse sequence of the target. Therefore, the echo signal of the scattering point is inter-pulse coherent. The fixed phase term is the same for each echo pulse within the imaging processing period and does not affect the blade imaging result; if each blade of the target rotor is regarded as composed of several scattering points distributed linearly, the translation phase term is the same for each scattering point within the same echo pulse, and only the phase change caused by translation between echo pulses needs to be compensated; the blade rotation plane is divided into several angular channels by angle, as Figure 4 shown. Then, by compensating the fixed phase difference caused by the position difference of the scattering points on the blade and the phase change between echo pulses caused by the rotation motion of each scattering point echo signal, and then performing coherent superposition processing, the distribution of the blade echo signal energy on the rotation circumference can be obtained, that is, the angular domain spatial imaging processing of the blade is completed, and then the number of target rotor blades can be distinguished. Thus, the core problem of imaging the helicopter rotor blade is transformed into the precise compensation of the phase of the echo signal of each scattering point on the blade.

[0030] In one embodiment, it is assumed that the target body echo signal has been separated and the blade translation phase has been compensated. As Figure 3 , it is assumed that the adjacent angular channel interval is , the rotation circumference is divided into a total of channels, the equivalent number of blade scattering points is ones, and the interval is . The pulse repetition period of the radar emission signal is denoted as . According to Equation (8), for the th scattering point on the blade, assuming that it is located in the th angular channel at the start time of the CPI (coherent processing interval), then the rotation phase compensation coefficient of the th echo pulse of this scattering point within the CPI can be expressed as: (9) is the total number of target echo pulses within the CPI interval.

[0031] If the angular channel where the blade is located at the start of CPI matches the above formula, its echo can be coherently accumulated after phase compensation, otherwise it cannot be effectively accumulated. The echo accumulation result of all scattering points in the angular channel within the CPI can be expressed as: (10) in is the target translation phase compensation coefficient.

[0032] By squaring the amplitude of the above formula, we can get the distribution of blade echo signal energy in each angular channel on the rotor's rotating circumference, that is, the blade imaging result: (11) It is worth noting that the above blade imaging algorithm requires prior knowledge of the target rotor speed. Secondly, for the value of the blade equivalent scattering point spacing, considering the impact of the scattering point phase change on the imaging quality and the algorithm calculation amount, it is advisable to ; Based on antenna theory and the physical characteristics of the blades on the target rotor, if the blades are regarded as a linear array antenna composed of several array elements, the main lobe width (3dB beam width) is: (12) in is the blade length, constant When the array elements are evenly distributed, the main lobe widening caused by the rotation of the blades can be comprehensively considered. To facilitate the algorithm implementation, the angle channel interval value can refer to the following formula: (13) Among them, the symbol In general, for C and X band air defense radars, the angular channel interval is rounded up to facilitate calculation. This can meet the angular spatial imaging requirements of the rotating parts. .

[0033] It should be understood that although Figure 2 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 2 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0034] In one embodiment, as Figure 5 shown, an imaging device for a target rotating component based on micro-Doppler phase compensation is provided, including: a spectral feature processing module 502, a translational phase compensation module 504, a rotational phase compensation module 506, and an imaging module 508, where: The spectral feature processing module 502 processes the overall echo pulse signal of the target based on micro-Doppler technology to obtain the prior information of the target rotating component and the separated echo pulse signal of the target rotating component.

[0035] The translational phase compensation module 504 is used to calculate the translational phase compensation coefficient of the target rotating component according to the prior information.

[0036] The rotational phase compensation module 506 is used to calculate the rotational phase compensation coefficient of the echo pulse of the scattering point of the target rotating component in the angular channel where the starting coherent processing moment is located according to the echo pulse signal of the target rotating component within the coherent processing interval.

[0037] The imaging module 508 is used to obtain the echo accumulation result of all scattering points of the target rotating component according to the translational phase compensation coefficient and the rotational phase compensation coefficient, and calculate the imaging result in the angular domain space according to the echo accumulation result.

[0038] For the specific limitations on the imaging device for the target rotating component based on micro-Doppler phase compensation, reference can be made to the limitations on the imaging method for the target rotating component based on micro-Doppler phase compensation in the above text, which will not be elaborated here. Each module in the above imaging device for the target rotating component based on micro-Doppler phase compensation can be implemented in whole or in part by software, hardware, and their combination. The above modules can be embedded in the processor of the computer device in hardware form or independent of it, or stored in the memory of the computer device in software form, so as to facilitate the processor to call and execute the operations corresponding to the above modules.

[0039] Those skilled in the art can understand that Figure 5 the structure shown in

[0040] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, storage, database, or other medium used in the embodiments provided by the present invention can include non-volatile and / or volatile memories. Non-volatile memories can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memories can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM), etc.

[0041] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0042] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. An imaging method for the rotating components of a target based on micro-Doppler phase compensation, characterized in that The method includes: Processing the overall echo pulse signal of the target based on the micro-Doppler technology to obtain the prior information of the target rotating component and the separated echo pulse signal of the target rotating component; Calculating the translational phase compensation coefficient of the target rotating component according to the prior information; Within the coherent processing interval, calculating the rotational phase compensation coefficient of the echo pulse of the scattering point of the target rotating component with respect to the echo pulse of the angular channel where the starting coherent processing moment is located according to the echo pulse signal of the target rotating component; Obtaining the echo accumulation result of all scattering points of the target rotating component according to the translational phase compensation coefficient and the rotational phase compensation coefficient, and calculating the imaging result in the angular domain space according to the echo accumulation result.

2. The method according to claim 1, characterized in that, Processing the overall echo pulse signal of the target based on the micro-Doppler technology to obtain the prior information of the target rotating component and the separated echo pulse signal of the target rotating component, including: Performing pulse compression processing on the overall pulse sequence of the target received by the radar based on the micro-Doppler technology, and analyzing the micro-Doppler spectrum characteristics of the target to obtain the prior information of the rotational speed of the target rotating component, and separating the echo pulse signal of the target body to obtain the separated echo signal of the target rotating component.

3. The method according to claim 2, wherein The prior information includes: the wavelength, bandwidth, linear chirp rate, pulse duration, target motion speed, distance from the center point of the target rotating component to the radar, and rotational angular velocity of the target rotating component; Calculating the translational phase compensation coefficient of the target rotating component according to the prior information, including: Separating the echo signal component of the target body according to the prior information, and calculating the echo pulse compression result of the scattering point on each blade of the target rotating component; Among them, is the distance from the scattering point on the target rotating component to the radar, is the signal after pulse compression of the echo of the scattering point, is the bandwidth of the radar transmitted signal, is the imaginary unit, is the pulse duration, is the radial distance from the center of the target rotating component to the radar, is the wavelength of the radar transmitted signal, is the Doppler frequency generated by the translational motion of the target body, is the speed of light, is the amplitude of the pulse compression result of the rotating component echo, is the fixed initial phase of the scattering point, is the translational Doppler modulation phase of the scattering point, is the rotational modulation phase of the echo signal of the scattering point, is the distance from the scattering point to the center of rotation, is the initial elevation angle of the center of the target rotating component in the space-fixed coordinate system, is the angular velocity of the blade rotation, is the angle between the blade and the positive x-axis of the space-fixed coordinate system at the initial moment; Obtaining the translational phase compensation coefficient of the scattering point on each angular channel of the target rotating component according to the echo signal of the scattering point; Among them, is the translational phase compensation coefficient, is the Doppler frequency generated by the translation of the target object, is the total number of angular channels, is the pulse duration.

4. The method according to claim 3, characterized in that Within the coherent processing interval, calculating the rotational phase compensation coefficient of the echo pulse of the scattering point of the target rotating component with respect to the echo pulse of the angular channel where the starting coherent processing moment is located according to the echo pulse signal of the target rotating component, including: Within the coherent processing interval, calculating the rotational phase compensation coefficient of the echo pulse of the scattering point of the target rotating component with respect to the echo pulse of the angular channel where the starting coherent processing moment is located according to the echo pulse signal of the target rotating component; wherein, is the rotational phase compensation coefficient of the echo pulse signal of the th target rotating component, is the serial number of the scattering point on the blade, is the echo pulse serial number, is the interval between adjacent scattering points, is the serial number of the angular channel, is the interval between adjacent angular channels, is the pulse repetition period, is the total number of echo pulse signals of the target rotating component within the coherent processing interval.

5. The method according to claim 4, characterized in that Obtaining the echo accumulation result of all scattering points according to the translational phase compensation coefficient and the rotational phase compensation coefficient, including: The echo accumulation result of all scattering points within the current angular channel according to the translational phase compensation coefficient and the rotational phase compensation coefficient; Among them, is the echo accumulation result of the th corner channel, is the translational phase compensation coefficient of the th echo pulse signal, is the rotational phase compensation coefficient of the echo pulse signal of the th target rotating component, is the pulse compression result of the th echo pulse of the target rotating component.

6. The method according to claim 5, characterized in that Calculating the imaging result in the angular domain space according to the echo accumulation result, including: Traversing and calculating the echo accumulation result after accumulating all angular channels to obtain the target echo signal, and calculating the imaging result of each angular channel blade on the rotating circumferential angle of the target rotating component according to the target echo signal; Among them, is the imaging result, is the echo accumulation result of the th corner channel, is the pulse repetition period, is the total number of scatter points.

7. An imaging device for a target rotating component based on micro-Doppler phase compensation, characterized in that The device includes: A spectrum feature processing module, configured to process the overall echo pulse signal of the target based on the micro-Doppler technology to obtain the prior information of the target rotating component and the separated echo pulse signal of the target rotating component; A translational phase compensation module, configured to calculate the translational phase compensation coefficient of the target rotating component according to the prior information; A rotation phase compensation module, which is used to calculate the rotation phase compensation coefficient of the echo pulse of the scattering point of the target rotating component with respect to the echo pulse in the angular channel where the starting coherent processing moment is located according to the echo pulse signal of the target rotating component within the coherent processing interval; An imaging module, which is used to obtain the echo accumulation result of all scattering points of the target rotating component according to the translational phase compensation coefficient and the rotation phase compensation coefficient, and calculate the imaging result in the angular domain space according to the echo accumulation result.

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