Vehicle-mounted microwave imaging method and application thereof

Abstract

The invention provides a vehicle-mounted microwave imaging method and application thereof, and the method comprises the steps: obtaining a first image through collecting the data of different vehicle-mounted antenna channels; performing hierarchical Doppler transform based on the first image to obtain a second image; performing spatial registration on the second image to obtain an aligned image; performing interpolation processing on the aligned image to obtain an interpolated image; and performing multi-stage Doppler comprehensive processing on the interpolated image to obtain a final microwave imaging result. The method comprises the following steps: acquiring a first image with low resolution, extracting a second image containing richer speed information through hierarchical Doppler transform, ensuring that a result of each level of transform corresponds to a consistent spatial position through spatial registration, and further performing single-machine Doppler interpolation to obtain a final image. According to the method, a high-definition microwave imaging result is obtained through multi-stage Doppler comprehensive processing, so that accurate speed and position analysis is realized.

Description

Technical Field

[0001] The present invention relates to the field of intelligent driving technology, and in particular to a vehicle-mounted microwave imaging method and application thereof. Background Art

[0002] Millimeter-wave radar uses electromagnetic waves in the millimeter-wave band (usually 24GHz to 77GHz) for detection and ranging. It can accurately detect and track targets around the vehicle, such as other vehicles, pedestrians, obstacles, etc. It has the ability to perceive all day and all weather without being restricted by lighting and climatic conditions, which is an advantage that optical sensors (such as cameras and lidar) cannot achieve. Millimeter-wave radar plays a vital role in the field of autonomous driving. The target detection, speed measurement and distance measurement capabilities it provides enable autonomous vehicles to drive safely and reliably in various complex environments. At present, there are two main problems with vehicle-mounted millimeter-wave radar: (1) Due to size limitations, it cannot provide high-resolution perception results.

[0003] (2) After point cloud processing, the perception results become even more sparse and cannot provide effective data for target recognition.

[0004] Therefore, there is an urgent need for a vehicle-mounted microwave imaging method and its application to improve the above problems. Summary of the invention

[0005] The object of the present invention is to provide a vehicle-mounted microwave imaging method and its application, which can obtain high-definition microwave imaging results to achieve accurate speed and position analysis.

[0006] In a first aspect, the present invention provides a vehicle-mounted microwave imaging method, comprising: Collect data from different vehicle-mounted antenna channels to obtain a first image; Performing hierarchical Doppler transformation based on the first image to obtain a second image; Performing spatial registration on the second image to obtain an aligned image; Performing interpolation processing on the aligned image to obtain an interpolated image; The interpolated image is subjected to multi-level Doppler comprehensive processing to obtain a final microwave imaging result.

[0007] The method of the present invention has the following beneficial effects: a first image is obtained by collecting data from different antenna channels on the vehicle; a second image is obtained by performing hierarchical Doppler transformation based on the first image; the second image is spatially registered to obtain an aligned image; the aligned image is interpolated to obtain an interpolated image; the interpolated image is subjected to multi-level Doppler comprehensive processing to obtain the final microwave imaging result. A low-resolution first image is first collected, and then a second image containing richer speed information is extracted through hierarchical Doppler transformation. Then, spatial registration is performed to ensure that the result of each level of transformation corresponds to a consistent spatial position. A single-machine Doppler interpolation is further performed to obtain an interpolated image containing more accurate speed information. Finally, a high-definition microwave imaging result is obtained through multi-level Doppler comprehensive processing to achieve accurate speed and position analysis.

[0008] Optionally, collecting data from different vehicle-mounted antenna channels to obtain the first image includes: Collect data from different vehicle-mounted antenna channels, where the data is in three dimensions: fast time, slow time, and channel; Performing a fast Fourier transform on the data along the fast time to obtain distance information, at which time the data domain is transformed into a distance-slow time-channel dimension; In the distance-slow time-channel data domain, a fast Fourier transform is performed along the channel dimension to obtain a first image; And / or the first image is a rough azimuth resolution image. The beneficial effect is that the data is subjected to fast Fourier transform along fast time to obtain distance information, which can reduce noise and improve distance resolution, and the obtained first image is convenient for subsequent fine processing.

[0009] Optionally, performing hierarchical Doppler transform based on the first image to obtain the second image includes: Performing multiple Doppler fast Fourier transform decomposition processes on the first image along the slow time dimension to form multi-level Doppler frequency bands, gradually decomposing the velocity components in the signal, and obtaining a result of hierarchical Doppler fast Fourier transform decomposition; Reconstructing Doppler information of different frequency bands step by step through the results of the hierarchical Doppler fast Fourier transform decomposition to obtain a reconstruction result; Using a bandpass filter to remove high-frequency noise in the reconstruction result in each level of Doppler transform to obtain a second image; And / or the high-frequency noise is removed by the Hamming window or Gaussian window function. Its beneficial effect is that the first image is subjected to multiple Doppler fast Fourier transform decomposition processes along the slow time dimension, each level of fast Fourier transform adds refined Doppler spectrum information to form a multi-level Doppler frequency band, and then the Doppler information of different frequency bands is reconstructed step by step to ensure that targets in different speed ranges can be accurately described, and high-frequency noise is removed to optimize the speed resolution.

[0010] Optionally, the second image is spatially registered to obtain an aligned image: Performing preliminary alignment on the second image so that the images at each level are consistent in spatial position; Based on the preliminary alignment results, sub-pixel registration technology is used to correct the position error; In the registration process, interpolation resampling is performed, so that images are accurately aligned at different scales when performing multi-resolution synthesis to obtain aligned images; And / or also includes performing spatial consistency correction on the aligned images so that echo information of different channels can be processed in a superimposed manner. Its beneficial effect is that by performing interpolation resampling during the registration process, images can be accurately aligned at different scales during multi-resolution synthesis, which can improve imaging accuracy, and consistency correction can eliminate deviations caused by differences in data from different channels, ensuring that echo information from different channels can be processed in a superimposed manner.

[0011] Optionally, performing single-stage Doppler interpolation processing on the aligned image to obtain an interpolated image includes: interpolating the single-level Doppler data of the aligned image to obtain interpolated data; And / or further comprising performing frequency domain smoothing on the interpolated data so that the interpolation does not cause frequency domain artifacts; And / or further comprising adjusting the interpolation factor according to the speed measurement requirement parameter so that the final image can meet the detailed speed information requirement; And / or also includes a consistency check of the interpolated data to correct the error introduced by the interpolation so that it is consistent with the original data in space. Its beneficial effect is that the sampling points are first increased by interpolation, and then smoothed by frequency domain to reduce the influence of noise and ensure that interpolation does not cause frequency domain artifacts, thereby obtaining more accurate speed information.

[0012] Optionally, performing multi-level Doppler comprehensive processing on the interpolated image to obtain a microwave imaging result includes: Performing level Doppler comprehensive processing on the interpolated image, fusing Doppler data of different levels, synthesizing velocity component information at different scales, and obtaining a comprehensive image; Removing high-frequency noise from the integrated image by using a frequency domain filter to make the speed information of the target clear; Performing enhancement processing on the integrated image to obtain an enhanced image; Outputting the enhanced image as a high-definition microwave imaging image to obtain a microwave imaging result; And / or the data fusion is performed by weighted average or least square method. The beneficial effect is that by fusing Doppler data of different levels, a high-definition microwave imaging result can be obtained, and the visibility of the image can be improved by image enhancement processing.

[0013] In a second aspect, the present invention provides a vehicle-mounted microwave imaging device, which includes modules / units for executing any possible design method of the first aspect. These modules / units can be implemented by hardware, or by hardware executing corresponding software implementations.

[0014] In a third aspect, the present invention provides an electronic device, comprising a memory and a processor, wherein the memory stores a program that can be run on the processor, and when the program is executed by the processor, the electronic device implements a method for executing any possible design of any of the above aspects.

[0015] In a fourth aspect, the present invention provides a readable storage medium, wherein the readable storage medium stores a program, and when the program is executed, it implements any possible design method of any of the above aspects.

[0016] In a fifth aspect, the present invention provides a computer program product, comprising a computer program, which implements the above method when executed by a processor.

[0017] For the beneficial effects of the second to fifth aspects, reference may be made to the description of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic flow chart of a vehicle-mounted microwave imaging method provided by an embodiment of the present invention; Figure 2 A schematic structural diagram of a vehicle-mounted microwave imaging device provided by an embodiment of the present invention; Figure 3 A schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0020] In view of the problem that the current vehicle-mounted millimeter-wave radar can neither provide high-resolution perception results nor provide effective data for target identification, the vehicle-mounted microwave imaging method provided by the present invention can obtain high-definition microwave imaging results to achieve accurate speed and position analysis. The technical scheme in the embodiment of the present invention is described below in conjunction with the drawings in the embodiment of the present invention. Among them, in the description of the embodiment of the present invention, the terms used in the following embodiments are only for the purpose of describing specific embodiments, and are not intended to be used as limitations on the present invention. The singular expressions "a", "said", "above", "the" and "this" are intended to also include expressions such as "one or more", unless there is a clear contrary indication in the context. It should also be understood that in the following embodiments of the present invention, "at least one", "one or more" refer to one or more than two (including two). The term "and / or" is used to describe the association relationship of associated objects, indicating that three relationships can exist; for example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the front and back associated objects are in an "or" relationship.

[0021] References to "one embodiment" or "some embodiments" described in this specification mean that one or more embodiments of the present invention include specific features, structures or characteristics described in conjunction with the embodiment. Thus, the statements "in one embodiment", "in some embodiments", "in some other embodiments", and "in some other embodiments" that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways. The term "connected" includes direct and indirect connections, unless otherwise stated. "First" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated.

[0022] In the embodiments of the present invention, "exemplarily" or "for example" is used to indicate an example, illustration or description. Any embodiment or design described as "exemplarily" or "for example" in the embodiments of the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of "exemplarily" or "for example" is intended to present the relevant concepts in a specific way.

[0023] like Figure 1 As shown, the present invention provides a vehicle-mounted microwave imaging method, comprising: S101, collecting data from different vehicle-mounted antenna channels to obtain a first image.

[0024] In some embodiments, in order to reduce noise and improve distance resolution, and to facilitate subsequent fine processing, data from different on-board antenna channels are collected to obtain a first image, including: collecting data from different on-board antenna channels, the data being in three dimensions of fast time, slow time, and channel; performing a fast Fourier transform on the data along the fast time to obtain distance information, at which time the data domain is transformed into a distance-slow time-channel dimension; performing a fast Fourier transform on the distance-slow time-channel data domain along the channel dimension to obtain the first image. In some specific embodiments, the first image is an azimuth coarse resolution image.

[0025] S102: Perform hierarchical Doppler transform based on the first image to obtain a second image.

[0026] In some embodiments, in order to increase the refined Doppler spectrum information, ensure that targets in different speed ranges can be accurately described, and remove high-frequency noise to optimize the speed resolution, a hierarchical Doppler transform is performed based on the first image to obtain a second image, including: performing multiple Doppler fast Fourier transform decomposition processes on the first image along the slow time dimension to form a multi-level Doppler frequency band, gradually decomposing the speed components in the signal, and obtaining the result of the hierarchical Doppler fast Fourier transform decomposition; reconstructing the Doppler information of different frequency bands step by step through the result of the hierarchical Doppler fast Fourier transform decomposition to obtain a reconstruction result; using a bandpass filter to remove the high-frequency noise in the reconstruction result in each level of Doppler transform to obtain the second image. In some specific embodiments, the high-frequency noise is removed by a Hamming window or a Gaussian window function.

[0027] S103: spatially register the second image to obtain an aligned image.

[0028] In some embodiments, in order to improve the imaging accuracy, the second image is spatially registered to obtain an aligned image: the second image is preliminarily aligned so that the images at each level are consistent in spatial position; sub-pixel registration technology is used based on the preliminary alignment result to correct the position error; interpolation resampling is performed during the registration process, and when performing multi-resolution synthesis, the images are accurately aligned at different scales to obtain an aligned image. In some specific embodiments, the aligned image is also spatially consistent, so that the echo information of different channels can be processed in a superimposed manner. The consistency correction can eliminate the deviation caused by the difference in data from different channels, ensuring that the echo information of different channels can be processed in a superimposed manner.

[0029] S104: performing interpolation processing on the aligned image to obtain an interpolated image.

[0030] In some embodiments, in order to increase the sampling points, reduce the impact of noise, and ensure that interpolation does not cause frequency domain artifacts, so as to obtain more accurate speed information, the aligned image is subjected to single-stage Doppler interpolation processing, and the interpolated image is obtained, including: interpolating the single-stage Doppler data of the aligned image to obtain the interpolated data. In some specific embodiments, it also includes frequency domain smoothing of the interpolated data so that interpolation does not cause frequency domain artifacts. In other specific embodiments, it also includes adjusting the interpolation factor according to the speed measurement requirement parameters so that the final image can meet the detailed speed information requirements. In some other specific embodiments, it also includes a consistency check on the interpolated data to correct the errors introduced by the interpolation so that it is consistent with the original data in space.

[0031] S105, performing multi-level Doppler comprehensive processing on the interpolated image to obtain a final microwave imaging result.

[0032] In some embodiments, performing multi-level Doppler comprehensive processing on the interpolated image to obtain a microwave imaging result includes: performing level Doppler comprehensive processing on the interpolated image, fusing Doppler data of different levels, synthesizing velocity component information at different scales, and obtaining a comprehensive image; removing high-frequency noise of the comprehensive image by a frequency domain filter to make the velocity information of the target clear; performing enhancement processing on the comprehensive image to obtain an enhanced image; outputting the enhanced image as a high-definition microwave imaging image to obtain a microwave imaging result. In some specific embodiments, the data fusion is performed by weighted average or least squares method.

[0033] For ease of understanding, this embodiment further describes the specific implementation process of the above method in combination with a specific application scenario system, which specifically includes the following steps: Step 1: Channel Azimuth Coarse Resolution Imaging The goal of this step is to obtain a low-resolution image to provide a reference for subsequent fine processing.

[0034] 1. Data acquisition: Collect sampling data from different antenna channels to ensure that sufficient Doppler information can be recorded during the acquisition process. The sampling data is in three dimensions: fast time, slow time, and channel.

[0035] 2. Range compression: Perform a fast Fourier transform (FFT) on the sampled data along the fast time to obtain the range information. At this time, the data domain is transformed into the range-slow time-channel dimension. Dechirp and window functions can be used to reduce noise and improve range resolution.

[0036] 3. Azimuth coarse resolution imaging: In the range-slow time-channel data domain, FFT is performed along the channel dimension to obtain a coarse resolution range-azimuth image (i.e., the first image). At this time, the data domain is range-slow time-azimuth. This coarse resolution image (i.e., the first image) will be used as the input for subsequent Doppler transform.

[0037] Step 2: Hierarchical Doppler Shift The purpose of hierarchical Doppler transform is to gradually extract richer velocity information in the step-by-step refinement and obtain higher velocity resolution.

[0038] 1. Multi-level FFT decomposition: The coarse-resolution image is subjected to multiple Doppler FFT decompositions along the slow time dimension. Each level of FFT adds refined Doppler spectrum information to form a multi-level Doppler frequency band, gradually decomposing the velocity component in the signal to obtain the result of hierarchical Doppler fast Fourier transform decomposition. At this time, the data domain is the range-Doppler-azimuth dimension.

[0039] 2. Frequency-band Doppler reconstruction: The Doppler information of different frequency bands is reconstructed step by step through the results of the hierarchical Doppler fast Fourier transform decomposition to ensure that targets in different speed ranges can be accurately described.

[0040] 3. Doppler filtering: Use a bandpass filter to remove high-frequency noise in each Doppler transform to obtain the second image. Window functions such as Hamming window or Gaussian window can be used to optimize velocity resolution.

[0041] Step 3: Spatial Registration In this step, the results of different Doppler grading are spatially aligned to ensure that the results of each level of transformation correspond to a consistent spatial position.

[0042] 1. Preliminary alignment: Perform preliminary alignment on the second image to ensure that the images at each level are consistent in spatial position.

[0043] 2. Sub-pixel registration: Based on the preliminary alignment results, sub-pixel registration technology is used, and phase correlation method is used for refined alignment to ensure that tiny position errors are corrected and imaging accuracy is improved.

[0044] 3. Interpolation resampling: Interpolation resampling is performed during the registration process, especially when multi-resolution fusion is required, to ensure that the images are accurately aligned at different scales to obtain the aligned images.

[0045] 4. Spatial consistency correction: The aligned images are corrected for spatial consistency to eliminate the deviation caused by the difference in data from different channels and ensure that the echo information from different channels can be superimposed for processing.

[0046] Step 4: Single-level Doppler interpolation The purpose of this step is to refine the Doppler resolution through interpolation method to obtain more accurate velocity information.

[0047] 1. Doppler interpolation processing: interpolate the single-level Doppler data of the aligned image, increase the sampling points, and obtain the interpolated data to improve the frequency domain resolution.

[0048] 2. Smoothing in the frequency domain: The interpolated data is smoothed in the frequency domain to reduce the impact of noise and ensure that interpolation does not cause frequency domain artifacts. A low-pass filter is used to smooth the Doppler distribution.

[0049] 3. Speed ​​resolution optimization: According to the specific speed measurement requirements, adjust the interpolation factor to ensure that the final image can meet the detailed speed information requirements.

[0050] 4. Doppler consistency correction: Check the consistency of the interpolated data to correct the small errors introduced by the interpolation and ensure that it is consistent with the original data in space.

[0051] Step 5: Multi-level Doppler synthesis This step will obtain high-definition microwave imaging results by fusing Doppler data at different levels.

[0052] 1. Multi-resolution fusion: Perform level Doppler comprehensive processing on the interpolated image, fuse Doppler data of different levels, synthesize velocity component information at different scales, and obtain a comprehensive image. Fusion can be performed by weighted averaging or least squares method.

[0053] 2. Filtering: The high-frequency noise of the integrated image is removed by a frequency domain filter to ensure that the speed information of the target is clear.

[0054] 3. Image enhancement: performing enhancement processing on the synthesized image, such as contrast stretching, noise removal, etc., to improve the visibility of the image.

[0055] 4. High-definition imaging output: Finally, the enhanced image is output as a high-definition microwave imaging map, and high-definition microwave imaging data of the target area is obtained to achieve accurate speed and position analysis.

[0056] like Figure 2 As shown, based on the above-mentioned vehicle-mounted microwave imaging method, the present invention provides a vehicle-mounted microwave imaging device, including: an acquisition unit 201, used to acquire data from different vehicle-mounted antenna channels to obtain a first image; a transformation unit 202, used to perform hierarchical Doppler transformation based on the first image to obtain a second image; a registration unit 203, used to perform spatial registration on the second image to obtain an aligned image; an interpolation unit 204, used to perform interpolation processing on the aligned image to obtain an interpolated image; and a synthesis unit 205, used to perform multi-level Doppler synthesis processing on the interpolated image to obtain a final microwave imaging result.

[0057] It should be understood that all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, which will not be repeated here. In addition, the use of suffixes such as "module", "component" or "unit" used to represent elements is only for the purpose of facilitating the description of the present invention, and has no specific meaning in itself. Therefore, "module", "component" or "unit" can be used in a mixed manner. The terminal can be implemented in various forms. For example, the terminal described in the present invention may include mobile terminals such as mobile phones, tablet computers, laptops, PDAs, portable media players (PMP), navigation devices, wearable devices, smart bracelets, pedometers, and fixed terminals such as digital TVs and desktop computers. The subsequent description will be described by taking the mobile terminal as an example, and those skilled in the art will understand that, in addition to components specifically used for mobile purposes, the construction according to the embodiment of the present invention can also be applied to fixed types of terminals.

[0058] In some other embodiments of the present invention, an electronic device 300 is disclosed. Figure 3 As shown, it may include: one or more processors 301; memory 302; display 303; one or more applications (not shown); and one or more computer programs 304. The above-mentioned components may be connected via one or more communication buses 305. The one or more computer programs 304 are stored in the above-mentioned memory 302 and configured to be executed by the one or more processors 301. The one or more computer programs 304 include instructions, which may be used to execute the following instructions: Figure 1 The various steps in the corresponding embodiments.

[0059] The processor 301 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

[0060] The memory 302 may be an internal storage unit of the electronic device 300, such as a hard disk or memory of the electronic device 300. The memory 302 may also be an external storage device of the electronic device 300, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card (FlashCard), etc. equipped on the electronic device 300. Further, the memory 302 may also include both an internal storage unit of the electronic device 300 and an external storage device. The memory 302 is used to store computer programs and other programs and data required by the electronic device. The memory 302 may also be used to temporarily store data that has been output or is to be output.

[0061] The computer program 304 may be divided into one or more modules / units. The one or more modules / units may be a series of computer program instruction segments capable of performing specific functions. The instruction segments are used to describe the execution process of the computer program 304 in the electronic device 300 .

[0062] In addition to the above structure, those skilled in the art can understand that Figure 3 It is only an example of the electronic device 300 and does not constitute a limitation of the electronic device 300. The electronic device 300 may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the electronic device may also include input and output devices, network access devices, buses, etc.

[0063] Those skilled in the art can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated into a processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of the present invention. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.

[0064] Based on the above embodiments, the present invention further discloses a computer-readable storage medium on which at least one computer program is stored. When the computer program is executed by a processor, a vehicle-mounted microwave imaging method in the above embodiments is implemented.

[0065] A person of ordinary skill in the art can understand that all or part of the steps in the method for implementing the above embodiment can be completed by instructing a processor through a program, and the program can be stored in a computer-readable storage medium, and the storage medium is a non-transitory medium, such as a random access memory, a read-only memory, a flash memory, a hard disk, a solid-state hard disk, a magnetic tape, a floppy disk, an optical disc, and any combination thereof. The above storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or a data center that includes one or more available media. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a digital video disc (DVD)), or a semiconductor medium (e.g., a solid-state disk (SSD)), etc.

[0066] The descriptions of the processes or structures corresponding to the above-mentioned figures have different emphases. For parts that are not described in detail in a certain process or structure, please refer to the relevant descriptions of other processes or structures.

[0067] In summary, the present invention discloses a vehicle-mounted microwave imaging method and its application, which first acquires a low-resolution first image, then extracts a second image containing richer speed information through hierarchical Doppler transform, and then performs spatial registration to ensure that the result of each level of transformation corresponds to a consistent spatial position, and further obtains an interpolated image containing more accurate speed information through single-machine Doppler interpolation, and finally obtains a high-definition microwave imaging result through multi-level Doppler comprehensive processing to achieve accurate speed and position analysis.

[0068] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A vehicle-mounted microwave imaging method, characterized in that: include: Collect data from different vehicle-mounted antenna channels to obtain a first image; Performing hierarchical Doppler transformation based on the first image to obtain a second image; Performing spatial registration on the second image to obtain an aligned image; Performing interpolation processing on the aligned image to obtain an interpolated image; The interpolated image is subjected to multi-level Doppler comprehensive processing to obtain a final microwave imaging result.

2. The method according to claim 1, characterized in that Collect data from different vehicle-mounted antenna channels to obtain the first image, including: Collect data from different vehicle-mounted antenna channels, where the data is in three dimensions: fast time, slow time, and channel; Performing a fast Fourier transform on the data along the fast time to obtain distance information, at which time the data domain is transformed into a distance-slow time-channel dimension; In the distance-slow time-channel data domain, a fast Fourier transform is performed along the channel dimension to obtain a first image; And / or the first image is an azimuth coarse-resolution image.

3. The method according to claim 1, characterized in that Performing hierarchical Doppler transform based on the first image to obtain a second image includes: Performing multiple Doppler fast Fourier transform decomposition processes on the first image along the slow time dimension to form multi-level Doppler frequency bands, gradually decomposing the velocity components in the signal, and obtaining a result of hierarchical Doppler fast Fourier transform decomposition; Reconstructing Doppler information of different frequency bands step by step through the results of the hierarchical Doppler fast Fourier transform decomposition to obtain a reconstruction result; Using a bandpass filter to remove high-frequency noise in the reconstruction result in each level of Doppler transform to obtain a second image; And / or remove high frequency noise via Hamming window or Gaussian window function.

4. The method according to claim 1, characterized in that: The second image is spatially registered to obtain an aligned image: Performing preliminary alignment on the second image so that the images at each level are consistent in spatial position; Based on the preliminary alignment results, sub-pixel registration technology is used to correct the position error; In the registration process, interpolation resampling is performed, so that images are accurately aligned at different scales when performing multi-resolution synthesis to obtain aligned images; And / or also includes performing spatial consistency correction on the aligned images so that echo information of different channels can be superimposed for processing.

5. The method according to claim 1, characterized in that Performing single-stage Doppler interpolation processing on the aligned image to obtain an interpolated image includes: interpolating the single-level Doppler data of the aligned image to obtain interpolated data; And / or further comprising performing frequency domain smoothing on the interpolated data so that the interpolation does not cause frequency domain artifacts; And / or further comprising adjusting the interpolation factor according to the speed measurement requirement parameter so that the final image can meet the detailed speed information requirement; And / or also includes performing a consistency check on the interpolated data to correct errors introduced by the interpolation so that the data is consistent with the original data in space.

6. The method according to claim 1, characterized in that The interpolated image is subjected to multi-level Doppler comprehensive processing to obtain microwave imaging results including: Performing level Doppler comprehensive processing on the interpolated image, fusing Doppler data of different levels, synthesizing velocity component information at different scales, and obtaining a comprehensive image; Removing high-frequency noise from the integrated image by using a frequency domain filter to make the speed information of the target clear; Performing enhancement processing on the integrated image to obtain an enhanced image; Outputting the enhanced image as a high-definition microwave imaging image to obtain a microwave imaging result; and / or data fusion via weighted averaging or least squares method.

7. A vehicle-mounted microwave imaging device, used in the method according to any one of claims 1 to 6, characterized in that: include: A collection unit, used for collecting data from different vehicle-mounted antenna channels to obtain a first image; A transform unit, configured to perform a hierarchical Doppler transform based on the first image to obtain a second image; A registration unit, configured to perform spatial registration on the second image to obtain an aligned image; An interpolation unit, used for performing interpolation processing on the aligned image to obtain an interpolated image; The synthesis unit is used to perform multi-level Doppler synthesis processing on the interpolated image to obtain the final microwave imaging result.

8. An electronic device, characterized in that: The electronic device comprises a memory and a processor, wherein the memory stores a program executable on the processor, and when the program is executed by the processor, the electronic device implements the method according to any one of claims 1 to 6.

9. A readable storage medium, wherein a program is stored in the readable storage medium, characterized in that: When the program is executed, the method according to any one of claims 1 to 6 is implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method according to any one of claims 1 to 6 is implemented.

Images