SAR (Synthetic Aperture Radar) speed estimation method based on overlapped view field and terminal

Abstract

The invention discloses an SAR radar speed estimation method and terminal based on an overlapped view field, and belongs to the technical field of radar speed measurement, and the method comprises the steps: delimiting a region where the front side radar observation range and the rear side radar observation range are overlapped as a combined observation region; radar pulse information of the combined observation area is intercepted; constructing an SAR joint velocity similarity matrix # imgabs0 # based on an overlapping field, and carrying out SAR radar velocity estimation; the determined SAR radar speed estimation interval is controlled to be gradually reduced, and the constructed joint speed similarity matrix # imgabs1 # is updated; and estimating the speed of the SAR radar for multiple times through the updated joint speed similarity matrix # imgabs2 # until the estimated speed of the SAR radar reaches preset precision, and outputting a final estimated value of the speed of the SAR radar. The reliability of speed estimation is improved, and the speed of the radar installation position can be accurately measured and calculated.

Description

Technical Field

[0001] The present invention relates to the technical field of radar speed measurement, and in particular to a SAR radar speed estimation method, device, intelligent terminal and storage medium based on overlapping fields of view. Background Art

[0002] Synthetic Aperture Radar (SAR) is an active microwave imaging radar system. Carried on platforms such as satellites, aircraft, or drones, it uses motion to create a virtual "large-aperture" antenna, producing high-resolution radar imagery far exceeding what is possible with the actual physical antenna size. SAR operates around the clock and in all weather conditions (it can penetrate clouds and a certain degree of vegetation / surface), and is widely used in topographic mapping, disaster monitoring (floods, earthquakes, landslides), ocean observation, resource exploration, and military reconnaissance.

[0003] The backprojection algorithm is a point-by-point imaging radar algorithm based on time-domain processing. It calculates round-trip delays and coherently accumulates corresponding signals to produce high-resolution Synthetic Aperture Radar (SAR) images. The accuracy of the velocity parameter plays a crucial role in the reliability of SAR imaging results. Only when the velocity parameter matches the actual radar velocity can the SAR imaging result accurately reflect the actual scene geometry and maintain image quality.

[0004] In existing vehicle-mounted SAR systems, high-precision inertial navigation systems (INS) can calculate velocity. However, due to size and cost considerations, a single high-precision INS is typically installed in a core location on the vehicle, such as the geometric center of the vehicle body, to ensure accurate and stable measurement data. However, this does not effectively reflect the exact velocity of a specific area of ​​the vehicle. Furthermore, to maximize the SAR sensing range, radars are typically mounted on all four sides of the vehicle (front left, rear left, front right, and rear right). This means that a single high-precision INS cannot accurately determine the SAR's velocity. This is especially true when the vehicle is traveling in a straight line at a non-uniform speed, such as during turns or sudden acceleration. The speed differences between local areas of the vehicle become more pronounced, making it difficult to accurately measure the velocity at the radar installation location.

[0005] Therefore, the existing technology still needs to be improved and developed. Summary of the Invention

[0006] In order to solve the above technical problems, the present invention provides a SAR radar speed estimation method, device, intelligent terminal and storage medium based on overlapping field of view. The present invention focuses on the problem of SAR radar speed acquisition, uses SAR itself to obtain precise speed, proposes and analyzes a SAR joint observation model based on overlapping field of view, designs a SAR radar speed estimation method based on the imaging similarity of the overlapping field of view observation area, and finally uses a precision progressive strategy for optimization. It can accurately estimate the precise speed of the front and rear radars of the vehicle-mounted SAR system.

[0007] A SAR radar velocity estimation method based on overlapping fields of view, comprising: A. Based on the geometric model diagram of the joint observation of the front-side and side-view dual SAR, the area where the front and rear radar observation ranges overlap is defined as the joint observation area; B. Based on the designated joint observation area, controlling the radar to transmit linear frequency modulation pulses to the detection area and intercepting radar pulse information in the joint observation area; C. Constructing a SAR joint velocity similarity matrix based on overlapping sites based on the joint observation area and the intercepted radar pulse information of the joint observation area ; Wherein, the SAR joint velocity similarity matrix The rows and columns correspond to the front radar speed and rear radar speed Discrete value of the front radar speed and rear radar speed Imaging is performed based on the radar speed of the row and column indices respectively, and the similarity of the two generated images is calculated and filled into the corresponding positions of the matrix; D. Estimate the SAR radar velocity based on the joint velocity similarity matrix. Find the row and column values ​​corresponding to the maximum value in the joint velocity similarity matrix, which are the preliminary estimated velocities of the front and rear radars, respectively, and determine the SAR radar velocity estimation interval. E. Control the gradual reduction of the SAR radar velocity estimation interval, and construct the joint velocity similarity matrix Make updates; F. Repeat the above radar velocity estimation steps and use the updated joint velocity similarity matrix , the SAR radar speed is estimated multiple times until the estimated SAR radar speed reaches a predetermined accuracy, and a final SAR radar speed estimation value is output.

[0008] In the SAR radar velocity estimation method based on overlapping fields of view, the step of defining the area where the front and rear radar observation ranges overlap as the joint observation area based on the front-view and side-view dual SAR joint observation geometric model diagram includes: Based on the geometric model diagram of the joint observation of the front-side dual-SAR, the two radars with the front-side observation mode are fixed at the front and rear positions on the same side of the vehicle platform. The front radar and the rear radar are respectively 、 express; Front and rear radars along Axis direction and along The axis is in the same position only along the There is spacing in the axial direction The radar observation range is represented by an ellipse. The area where the front and rear radar observation ranges overlap is called the joint observation area.

[0009] In the SAR radar velocity estimation method based on overlapping fields of view, the steps of controlling the radar to transmit linear frequency modulation pulses to the detection area based on the defined joint observation area and intercepting radar pulse information in the joint observation area include: Based on the defined joint observation area, the radar is controlled to transmit linear frequency modulation pulses to the detection area, and the signal is reflected by the target and received by the radar; Acquire front and rear radar data and vehicle-mounted platform speed data, and analyze the synthetic aperture length of the joint observation based on the joint observation area.

[0010] The SAR radar velocity estimation method based on overlapping fields of view, wherein the radar pulse information of the joint observation area and the intercepted joint observation area is used to construct a SAR joint velocity similarity matrix based on overlapping fields of view. The steps include: Based on the joint observation area and the intercepted radar pulse information of the joint observation area, a SAR joint velocity similarity matrix based on overlapping sites is constructed. ; SAR joint velocity similarity matrix The rows and columns correspond to the front radar speed and rear radar speed The initial discretization interval is set to 1m / s; Through and Discretize it, divide its value range into a finite set of discrete points, and combine all the speeds as element indexes into matrices; For each element in the matrix , by using SAR imaging algorithms, using Process the front radar echo data and get the front imaging matrix as ;use Process the rear radar echo data and obtain the rear imaging matrix: , calculate the similarity and fill the result into the corresponding position of the matrix.

[0011] The SAR radar velocity estimation method based on overlapping fields of view, wherein the control gradually narrows the determined SAR radar velocity estimation interval, and the constructed joint velocity similarity matrix The steps to perform the update include: In constructing the joint velocity similarity matrix Find the row and column values ​​corresponding to the maximum value, reduce the discretization interval to one tenth of the original, and take the row and column values ​​before and after the corresponding maximum value. Speed ​​value, get the new speed ; For each element in the matrix , using SAR imaging algorithms and updated speed , calculate the similarity and fill the result into the joint speed similarity matrix Corresponding position, the joint velocity similarity matrix to update.

[0012] The SAR radar velocity estimation method based on overlapping fields of view, wherein the above steps are repeated to obtain the updated joint velocity similarity matrix The steps of estimating the SAR radar velocity multiple times until the estimated SAR radar velocity reaches a predetermined accuracy and outputting a final SAR radar velocity estimation value include: Through the joint velocity similarity matrix , perform SAR radar velocity estimation three times until the estimated SAR radar velocity reaches a predetermined accuracy, for example, the accuracy reaches 0.01 m / s; then output the final SAR radar velocity estimation value.

[0013] The SAR radar velocity estimation method based on overlapping fields of view, wherein the above steps are repeated to obtain the updated joint velocity similarity matrix The steps of estimating the SAR radar velocity multiple times until the estimated SAR radar velocity reaches a predetermined accuracy and outputting a final SAR radar velocity estimation value include: Repeat the above steps and combine the speed similarity matrix , perform SAR radar velocity estimation three times until the estimated SAR radar velocity reaches a predetermined accuracy, for example, the accuracy reaches 0.01 m / s; then output the final SAR radar velocity estimation value; The accuracy of the first stage is 1m / s, the second stage is accurate to 0.1m / s, and the third stage is accurate to 0.01m / s, and the final SAR radar velocity estimate is output.

[0014] A SAR radar velocity estimation device based on overlapping fields of view, wherein the device comprises: The joint observation area delineation module is used to delineate the area where the front and rear radar observation ranges overlap as the joint observation area based on the geometric model diagram of the front-side and side-view dual SAR joint observation; An interception module is used to control the radar to transmit linear frequency modulation pulses to the detection area based on the demarcated joint observation area, and intercept radar pulse information in the joint observation area; A matrix construction module is used to construct a SAR joint velocity similarity matrix based on overlapping sites based on the joint observation area and the intercepted radar pulse information of the joint observation area ; Wherein, the SAR joint velocity similarity matrix The rows and columns correspond to the front radar speed and rear radar speed Discrete value of the front radar speed and rear radar speed Imaging is performed based on the radar speed of the row and column indices respectively, and the similarity of the two generated images is calculated and filled into the corresponding positions of the matrix; The speed estimation module is used to estimate the SAR radar speed based on the joint speed similarity matrix. The row and column values ​​corresponding to the maximum value in the joint speed similarity matrix are used as the preliminary estimated speeds of the front and rear radars, respectively, to determine the SAR radar speed estimation interval. The matrix update module is used to control the gradual reduction of the determined SAR radar velocity estimation interval and the constructed joint velocity similarity matrix Make updates; Repeat estimation and final output module, used to repeat the above steps, through the updated joint speed similarity matrix , the SAR radar speed is estimated multiple times until the estimated SAR radar speed reaches a predetermined accuracy, and a final SAR radar speed estimation value is output.

[0015] An intelligent terminal includes a memory and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by one or more processors, including the method for executing any one of the methods described above.

[0016] A computer-readable storage medium, wherein when instructions in the storage medium are executed by a processor of an electronic device, the electronic device is enabled to perform any one of the methods described above.

[0017] As can be seen from the above, this application provides a SAR radar speed estimation method, device, intelligent terminal and storage medium based on overlapping field of view, proposes and analyzes a SAR joint observation model based on overlapping field of view, designs a SAR radar speed estimation method based on the imaging similarity of the overlapping field of view observation area, and finally uses a precision progressive strategy for optimization. This method has good generalization ability for different scenarios, improves the reliability of speed estimation, and can accurately measure the speed of the radar installation location. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 1 is a flow chart of a SAR radar velocity estimation method based on overlapping fields of view provided in Example 1 of the present invention.

[0020] Figure 2 3 is a flow chart of a SAR radar velocity estimation method based on overlapping fields of view provided in Example 2 of the present invention.

[0021] Figure 3 It is a schematic diagram of a geometric model of a joint observation of two SARs with front and side views in a SAR radar velocity estimation method based on overlapping fields of view provided by an embodiment of the present invention.

[0022] Figure 4 3 is a schematic diagram of a joint observation model projection model of a SAR radar velocity estimation method based on overlapping fields of view provided by an embodiment of the present invention.

[0023] Figure 5 1 is a schematic diagram of a preliminary experimental optical scene of a SAR radar velocity estimation method based on overlapping fields of view provided by an embodiment of the present invention.

[0024] Figure 6a and Figure 6b This is a result effect diagram of the radar using the first stage of estimated velocity imaging in the SAR radar velocity estimation method based on overlapping fields of view provided in an embodiment of the present invention.

[0025] Figure 7a and Figure 7b This is a result effect diagram of the radar using the second stage of estimated velocity imaging in the SAR radar velocity estimation method based on overlapping fields of view provided in an embodiment of the present invention.

[0026] Figure 8a and Figure 8bThis is a result effect diagram of the radar using the third stage of velocity estimation imaging in the SAR radar velocity estimation method based on overlapping fields of view provided by an embodiment of the present invention.

[0027] Figure 9 A principle block diagram of an embodiment of a SAR radar velocity estimation device based on overlapping fields of view provided by the present invention.

[0028] Figure 10 This is a block diagram of the internal structure of the smart terminal provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clear and distinct, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0030] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0031] As seen in the imaging algorithm's processing of radar echo data, the accuracy of the velocity parameter is crucial to the reliability of SAR imaging results. Only when the velocity parameter matches the actual radar velocity can the SAR imaging results accurately reflect the geometry of the real scene and guarantee image quality. While high-precision inertial navigation systems (INS) can calculate velocity, their size and cost restrict their installation locations, making them unable to accurately measure velocity at the radar's location.

[0032] In existing vehicle-mounted SAR systems, high-precision inertial navigation systems (INS) can calculate velocity. However, due to size and cost considerations, a single high-precision INS is typically installed in a core location on the vehicle, such as the geometric center of the vehicle body, to ensure accurate and stable measurement data. However, this does not effectively reflect the exact velocity of a specific area of ​​the vehicle. Furthermore, to maximize the SAR sensing range, radars are typically mounted on all four sides of the vehicle (front left, rear left, front right, and rear right). This means that a single high-precision INS cannot accurately determine the SAR's velocity. This is especially true when the vehicle is traveling in a straight line at a non-uniform speed, such as during turns or sudden acceleration. The speed differences between local areas of the vehicle become more pronounced, making it difficult to accurately measure the velocity at the radar installation location.

[0033] In order to solve the above problems, this application proposes a SAR radar velocity estimation method based on overlapping fields of view, as described in the following embodiments: Example 1 like Figure 1 As shown, a SAR radar velocity estimation method based on overlapping fields of view according to a first embodiment of the present invention includes the following steps: Step S100: Based on the front-side dual-SAR joint observation geometric model diagram, define the area where the front and rear radar observation ranges overlap as the joint observation area; The geometric model diagram of the joint observation of the front-view and side-view dual SARs is a schematic diagram for describing the spatial position relationship, signal propagation path, and geometric relationship between the target and the radar of two synthetic aperture radars (SARs) in the front-view and side-view observation modes.

[0034] The basic components of the geometric model diagram of the front-side dual-SAR joint observation include: Radar Platforms: The diagram shows two SAR platforms, which can be airborne, satellite-based, or ground-based. Each platform has its own position and motion state, which may be uniform linear motion or other complex trajectories. Parameters such as the platform's flight direction and speed are indicated.

[0035] Target area: This represents the object being observed, which may be a ground scene, an ocean surface, or other area of ​​interest. The coordinates of the target area are typically set in the image. The center of the scene can be set as the coordinate origin, and the target position is represented by three-dimensional coordinates (x, y, z).

[0036] Signal Propagation Path: This displays the path that a radar signal takes from the transmitter to the target, and then back to the receiver. These paths allow you to determine geometric relationships, such as slant range, between the radar and the target. Key distance parameters, such as the minimum vertical slant range, are also displayed.

[0037] In this step embodiment, based on the front and side dual SAR joint observation geometric model diagram, as shown in FIG. Figure 3 As shown in the figure, the joint observation area of ​​the vehicle-mounted front and side-view dual radars is delineated. The observation mode is that the two front and side-view radars are fixed at the front and rear positions on the same side of the vehicle-mounted platform. The front radar and the rear radar are respectively 、 Indicates that the front and rear radars are along Axis direction and along The axis is in the same position only along the There is spacing in the axial direction The radar observation range is represented by an ellipse, and the gray area represents the area where the front and rear radar observation ranges overlap, which is called the joint observation area.

[0038] Step S200: Based on the defined joint observation area, controlling the radar to transmit linear frequency modulation pulses to the detection area, and intercepting radar pulse information of the joint observation area; In this step, based on the designated joint observation area, the radar is controlled to transmit linear frequency modulation pulses to the detection area. The signal is received by the radar after being reflected by the target. The front and rear radar data and the INS vehicle platform speed data are obtained. The synthetic aperture length of the joint observation is further analyzed according to the joint observation area. Figure 4 The joint observation model of two moments is approximately projected onto Since the two radars work synchronously, taking the front pulse of the front radar and the rear pulse of the rear radar can ensure that the front and rear radars have the same synthetic aperture time for the point target in the data segment.

[0039] like Figure 4 The joint observation model of two moments is approximately projected onto At the initial moment, the front radar is located at The rear radar is located at The radar distance is always maintained at ; As the platform moves, at the final moment, the front radar is located at The rear radar is located at The green and yellow lines are used to depict the illumination range of the front and rear radars respectively. It is the farthest point on the left edge of the front radar illumination range. It is the farthest point on the right edge of the rear radar illumination range. and They are the nearest and farthest intersection points of the front and rear radar illumination ranges respectively, and the gray area enclosed is the joint observation area.

[0040] Assume there is a stationary target in the scene At the initial moment, the point is located at the farthest point on the right edge of the front radar illumination range, and at the final moment, it is located at the farthest point on the left edge of the front radar illumination range. The synthetic aperture length of the target point with respect to the front radar is The rear radar only moves to The point target can only be illuminated when the target is at the rear radar. Therefore, during this period of time, the synthetic aperture length of the target point with respect to the rear radar is Since the two radars operate synchronously, taking the front pulse of the front radar and the rear pulse of the rear radar ensures that the front and rear radars have the same synthetic aperture time for point targets in the acquired data segment. The acquired radar data is then imaged separately.

[0041] Taking TI's AWR2243 radar data as an example, the sub-aperture imaging method is used to select the number of single-frame echoes. , that is, the amount of data for a single frame is ( Corresponding to the distance dimension data volume, Corresponding to the azimuth dimension data volume), take the 100th to The second echo is the front radar echo data, and the rear radar current frame 0 to The secondary echo is the rear radar echo data.

[0042] Step S300: Constructing a SAR joint velocity similarity matrix based on overlapping sites based on the joint observation area and the intercepted radar pulse information of the joint observation area ; Wherein, the SAR joint velocity similarity matrix The rows and columns correspond to the front radar speed and rear radar speed Discrete value of the front radar speed and rear radar speed Imaging is performed based on the radar speed of the row and column indices respectively, and the similarity of the two generated images is calculated and filled into the corresponding positions of the matrix.

[0043] In this step, a joint speed similarity matrix is ​​constructed. The rows and columns of the matrix correspond to the front radar speed and rear radar speed The initial discretization interval is 1m / s, for example for By monitoring the front radar speed and rear radar speed Discretize it, divide its value range into a finite set of discrete points, and combine all possible speed combinations As the element index of the matrix. For each element in the matrix , by using a suitable SAR imaging algorithm, using Process the front radar echo data and get the front imaging matrix as ;use Process the rear radar echo data and obtain the rear imaging matrix: , calculate their similarity and fill the results into the corresponding positions of the matrix.

[0044] Step S400: Estimate the SAR radar speed based on the joint speed similarity matrix. Find the row and column values ​​corresponding to the maximum value in the joint speed similarity matrix, which are the preliminary estimated speeds of the front and rear radars, respectively, and determine the SAR radar speed estimation interval.

[0045] Specifically, in an embodiment of the present invention, when performing dual-radar joint velocity estimation, the similarity of the imaging results of the front and rear radars in the joint observation area is used as a basis for searching for the most similar pair of imaging results. The front and rear radar velocity values ​​corresponding to this pair of imaging results are considered to be the accurate velocities of the front and rear radars at the sub-aperture time, thereby achieving joint velocity estimation of the front and rear radars.

[0046] Specifically, the SAR imaging results after algorithm processing are saved in the form of complex matrices. Therefore, the problem of determining whether two SAR images are similar can be converted into the problem of measuring the similarity of two complex matrices. The Pearson correlation coefficient is used to quantify the similarity of the two complex matrices. Assuming that the front radar and the rear radar respectively collect echo data during the same joint observation period. Using the front radar reference velocity Process the front radar echo data and get the front imaging matrix as ; Use the rear radar reference speed parameter Process the rear radar echo data and obtain the rear imaging matrix: , then their Pearson coefficients are expressed as Formula 1 in is a matrix and The covariance of and They represent the variance of the two matrices respectively.

[0047] In order to achieve speed estimation, a joint speed similarity matrix is ​​constructed The rows and columns of the matrix correspond to the front radar reference velocity and rear radar reference speed The discrete value of . and Discretize it, divide its value range into a finite set of discrete points, and combine all possible speed combinations As the element index of the matrix. For each element in the matrix , the imaging algorithm uses the velocity parameter and Calculate the imaging matrix of the front and rear radars respectively and , calculate their similarity using the above formula 1 and fill the result into the corresponding position in the matrix. Therefore, estimating the accurate velocity of the front and rear radars during the same joint observation period is to find the row and column values ​​corresponding to the maximum value in the joint velocity similarity matrix.

[0048] As can be seen from the above, in the embodiment of the present invention, the joint speed similarity matrix constructed Find the row and column values ​​corresponding to the maximum value, which are the preliminary estimated speeds of the front and rear radars, respectively, and determine the preliminary SAR radar speed estimation range.

[0049] In order to achieve more accurate SAR radar velocity estimation in the embodiment of the present invention, a velocity estimation strategy with progressive precision is adopted, as specifically described in steps S500 and S600.

[0050] Step S500: Control the SAR radar velocity estimation interval to be gradually narrowed down, and construct the joint velocity similarity matrix Make updates; Control the speed estimation interval to gradually reduce and update the joint speed similarity matrix. Find the row and column values ​​corresponding to the maximum value in the joint speed similarity matrix, reduce the discretization interval to one tenth of the original, and take the row and column values ​​before and after the maximum value in this interval. Speed ​​value, get the new speed For each element in the matrix , by using SAR imaging algorithms and updated speed , calculate the similarity and fill the result into the joint speed similarity matrix Corresponding position, the joint velocity similarity matrix to update.

[0051] Step S600: Repeat the above steps to update the joint velocity similarity matrix , the SAR radar speed is estimated multiple times until the estimated SAR radar speed reaches a predetermined accuracy, and a final SAR radar speed estimation value is output.

[0052] In the embodiment of the present invention, it is preferable that the predetermined accuracy can be achieved by three speed estimates; that is, the updated joint speed similarity matrix The row and column values ​​corresponding to the maximum value are found in the second-stage medium-precision estimation. The final velocity estimation interval is then determined based on the discretization interval, which is then refined to one-tenth the previous estimate. The joint velocity similarity matrix is ​​then updated again, with the row and column values ​​corresponding to the maximum value in this joint velocity similarity matrix representing the final estimated velocities of the front and rear radars, respectively. This stepwise optimization of multiple estimations yields precise velocity estimates, effectively improving the efficiency of velocity estimation while maintaining accuracy.

[0053] In the embodiment of the present invention, preferably, the above steps are repeated to combine the speed similarity matrix The process continues approximately three times until the estimated SAR radar velocity reaches a predetermined accuracy, for example, 0.01 m / s. The final SAR radar velocity estimate is then output. In other words, in this embodiment of the present invention, the second stage involves updating the velocity similarity matrix and performing a second velocity estimate. The accuracy of the first stage is 1 m / s, the second stage is accurate to 0.1 m / s, and the third stage is accurate to 0.01 m / s. The final SAR radar velocity estimate is then output.

[0054] As can be seen from the above, in the system of the present invention, the vehicle center velocity calculated by the high-precision INS is used as a reference value to determine the initial radar velocity for the joint velocity estimation method, effectively shortening the velocity estimation interval. Furthermore, in the event of partial loss of radar echo data, the INS can fill the gaps in the SAR velocity estimation. Furthermore, the velocity information provided by the joint velocity estimation method can be used to calibrate the INS, addressing the problem of error accumulation in the acceleration integration process.

[0055] The progressively more precise speed estimation strategy achieves accurate speed estimation by gradually refining the search range and discretization interval. This strategy is divided into three stages: preliminary rough estimation, medium-precision estimation, and high-precision estimation. In the first stage, the speed estimation range is initially determined based on the INS, with a discretization interval of 1 m / s. In the second round, based on the results of the first stage, the speed range is further narrowed, and the discretization interval is reduced to 0.1 m / s. In the third stage, the speed range is further narrowed based on the medium-precision estimate, and the discretization interval is further reduced to 0.01 m / s to refine the search interval. This multi-stage, step-by-step optimization process yields accurate speed estimates, effectively improving the efficiency of speed estimation while maintaining accuracy.

[0056] As can be seen from the above, the present invention proposes and analyzes a SAR joint observation model based on overlapping fields of view, designs a SAR radar velocity estimation method based on the imaging similarity of the overlapping field of view observation area, and finally uses a precision progressive strategy for optimization. This method has good generalization ability for different scenarios and improves the reliability of velocity estimation.

[0057] The present invention is further described in detail below through another specific application embodiment.

[0058] Example 2 like Figure 2 As shown, the second embodiment provides a SAR radar velocity estimation method based on overlapping fields of view, including: S10, based on the geometric model diagram of the joint observation of the front-side dual-SAR, analyze the original radar data, delineate the joint observation area, and proceed to S11; S11, based on the demarcation of the joint observation area, controlling the radar to transmit linear frequency modulation pulses to the detection area, and intercepting radar pulse information of the joint observation area, and then proceeding to S13; S12, determine the speed estimation interval, and enter S13 again; S13, based on the joint observation area and the intercepted radar pulse information of the joint observation area, constructing a SAR joint velocity similarity matrix based on overlapping sites ; Wherein, the SAR joint velocity similarity matrix The rows and columns correspond to the front radar speed and rear radar speed The front and rear radar pulse data are imaged according to the radar speed of the row and column indexes respectively, and the similarity of the two generated images is calculated and filled in the corresponding positions of the matrix; S14, finding the row and column values ​​corresponding to the maximum value position in the SAR radar speed estimated by the constructed joint speed similarity matrix, which are the preliminary estimated speeds of the front and rear radars respectively, and then proceeding to S12 to determine the preliminary SAR radar speed estimation interval, and then proceeding to S15; S15, controlling the gradual reduction of the determined preliminary SAR radar velocity estimation interval to enter the re-determined SAR radar velocity estimation interval of S12, and constructing the joint velocity similarity matrix Update and use the updated joint velocity similarity matrix , re-update the joint velocity similarity matrix Find the row and column values ​​corresponding to the maximum value, which are the second estimated speeds of the front and rear radars respectively, and determine them as the second SAR radar speed estimation interval; In the embodiment of the present invention, preferably, the above steps are repeated to combine the speed similarity matrix The process continues approximately three times until the estimated SAR radar velocity reaches a predetermined accuracy, for example, 0.01 m / s. The final SAR radar velocity estimate is then output. In other words, in this embodiment of the present invention, the second stage involves updating the velocity similarity matrix and performing a second velocity estimate. The accuracy of the first stage is 1 m / s, the second stage is accurate to 0.1 m / s, and the third stage is accurate to 0.01 m / s. The final SAR radar velocity estimate is then output.

[0059] In this specific application embodiment, SAR radar velocity estimation based on overlapping fields of view uses an AWR2243 radar signal module and a DCA1000 acquisition board to collect SAR data. Figure 5This is an image of the experimental optical scene. Metal balls and corner reflectors have strong reflectivity and can produce significant echo signals. Other targets, such as carts and steps, can also be used as calibration targets for effect analysis.

[0060] Figure 6a and Figure 6b The result of the first stage estimated velocity imaging is used by the radar. Then the BP imaging algorithm is used. Figure 6a It is the front radar result. Figure 6b This is the result from the rear radar. The first-stage velocity estimation yielded a velocity value of 5 m / s for the front radar and 5 m / s for the rear radar. The rough velocity estimates obtained in the first stage are compared to the actual scene. Positional distortion of the target in the joint velocity estimation area in the SAR image is evident, indicating that the velocity estimates in the first stage are slightly higher than the actual velocity.

[0061] Figure 7a and Figure 7b The following are the results of radar imaging using the second-stage velocity estimation: front and rear estimation velocity imaging. The second-stage velocity estimation yielded a front radar velocity of 4.2 m / s and a rear velocity of 4.1 m / s. The targets in the joint velocity estimation area in SAR imaging accurately reproduce the actual scene object information, with the corner reflector and cart positioned correctly. Furthermore, the curvature and clustering of the step imaging results for the linear spheres have been reduced.

[0062] Figure 8a and Figure 8b This is the result of the third-stage velocity estimation of the radar. The third-stage velocity estimation yields a front radar velocity of 4.18 m / s and a rear radar velocity of 4.09 m / s.

[0063] The experimental results are shown in Table 1: Table 1

[0064] Table 1 shows the velocity estimates and their corresponding correlation coefficients for the three phases. The Pearson correlation coefficient is used to quantify the similarity of the SAR imaging results. The correlation coefficients for the velocities obtained in the three phases are 0.617, 0.898, and 0.903, respectively.

[0065] The vehicle-mounted front-side combined SAR system collected dual radar echo data for the scene, carried out velocity estimation according to a three-stage precision progression strategy, and used the velocity of the third stage for sub-aperture imaging to verify the accuracy of the velocity estimation results.

[0066] Table 1 above lists the front radar velocity estimates for the three stages respectively. and rear radar velocity estimates , and the correlation coefficient values ​​corresponding to the anterior and posterior imaging results ; Figure 6a and Figure 6b 、 Figure 7a and Figure 7b and pictures, Figure 8a and Figure 8b The imaging results of the joint velocity estimation area by the left and right radars after the three stages of velocity estimation are shown respectively.

[0067] Exemplary devices like Figure 9 As shown, an embodiment of the present invention provides a SAR radar velocity estimation device based on overlapping fields of view, the device comprising: The joint observation area delineation module 310 is configured to delineate the area where the front and rear radar observation ranges overlap as the joint observation area based on the front-side and side-view dual SAR joint observation geometric model diagram; The interception module 320 is used to control the radar to transmit linear frequency modulation pulses to the detection area based on the demarcated joint observation area, and intercept radar pulse information in the joint observation area; The matrix construction module 330 is used to construct a SAR joint velocity similarity matrix based on overlapping sites based on the joint observation area and the intercepted radar pulse information of the joint observation area. ; Wherein, the SAR joint velocity similarity matrix The rows and columns correspond to the front radar speed and rear radar speed Discrete value of the front radar speed and rear radar speed Imaging is performed based on the radar speed of the row and column indices respectively, and the similarity of the two generated images is calculated and filled into the corresponding positions of the matrix; The speed estimation module 340 is used to estimate the SAR radar speed based on the joint speed similarity matrix, find the row and column values ​​corresponding to the maximum value in the joint speed similarity matrix, and use them as the preliminary estimated speeds of the front and rear radars, respectively, to determine the SAR radar speed estimation interval; The matrix updating module 350 is used to control the gradual reduction of the determined SAR radar velocity estimation interval and to update the constructed joint velocity similarity matrix Make updates; Repeat estimation and final output module 360 ​​is used to repeat the above steps and obtain the updated joint speed similarity matrix , the SAR radar speed is estimated multiple times until the estimated SAR radar speed reaches a predetermined accuracy, and a final SAR radar speed estimation value is output.

[0068] Based on the above embodiment, the present invention also provides an intelligent terminal, whose principle block diagram can be shown as follows: Figure 10 As shown, the smart terminal includes a processor, memory, network interface, display screen, and database connected via a system bus. The processor of the smart terminal is used to provide computing and control capabilities. The memory of the smart terminal includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and computer program in the non-volatile storage medium. The network interface of the smart terminal is used to communicate with an external terminal via a network connection. When the computer program is executed by the processor, a method for displaying terminal dynamic wallpaper in real time based on local weather is implemented. The database of the smart terminal is used to store a program for displaying terminal dynamic wallpaper in real time based on local weather.

[0069] Those skilled in the art will understand that Figure 4 The principle block diagram shown in the figure is only a block diagram of a partial structure related to the solution of the present invention and does not constitute a limitation on the smart terminal to which the solution of the present invention is applied. The specific smart terminal may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0070] In one embodiment, a smart terminal is provided, comprising a memory and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by one or more processors, wherein the one or more programs include instructions for performing the following operations.

[0071] Those skilled in the art will appreciate that all or part of the processes in the above-described method embodiments can be implemented by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the above-described method embodiments. Any reference to memory, storage, database, or other media used in the various embodiments provided herein may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct RAMbus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM).

[0072] The present application further proposes a computer-readable storage medium. When instructions in the storage medium are executed by a processor of an electronic device, the electronic device is enabled to perform a SAR radar velocity estimation method based on overlapping fields of view.

[0073] The term "computer-readable storage medium" refers to a physical medium used to store executable program code, specifically a storage device such as a solid-state drive, flash memory chip, or optical disk. It carries the program instructions for implementing the SAR radar velocity estimation method based on overlapping fields of view. Processor execution refers to the reading and operation of the program code from the storage medium by a central processing unit, specifically a multi-core processor or distributed computing architecture.

[0074] The above description is merely an embodiment of the present application and is not intended to limit the scope of protection of the present application. For those skilled in the art, various modifications and variations of the present application are possible. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A SAR radar velocity estimation method based on overlapping fields of view, characterized in that: include: Based on the geometric model diagram of the joint observation of the front-side and side-view dual SAR, the area where the front and rear radar observation ranges overlap is defined as the joint observation area; Based on the defined joint observation area, controlling the radar to transmit linear frequency modulation pulses to the detection area and intercepting radar pulse information of the joint observation area; Based on the joint observation area and the intercepted radar pulse information of the joint observation area, a SAR joint velocity similarity matrix based on overlapping sites is constructed; wherein the rows and columns of the SAR joint velocity similarity matrix correspond to discrete values ​​of the front radar velocity and the rear radar velocity, respectively; the front radar velocity and the rear radar velocity are imaged according to the radar velocities indexed by the rows and columns, and similarities are calculated for the two generated images and filled into corresponding positions in the matrix; Estimate the SAR radar speed based on the joint speed similarity matrix, find the row and column values ​​corresponding to the maximum value in the joint speed similarity matrix, which are the preliminary estimated speeds of the front and rear radars respectively, and determine the SAR radar speed estimation interval; Controlling the gradual reduction of the determined SAR radar velocity estimation interval and updating the constructed joint velocity similarity matrix; Repeat the above radar velocity estimation steps, estimate the SAR radar velocity multiple times through the updated joint velocity similarity matrix, until the estimated SAR radar velocity reaches a predetermined accuracy, and output the final SAR radar velocity estimation value.

2. The SAR radar velocity estimation method based on overlapping fields of view according to claim 1, characterized in that: The step of defining the area where the front and rear radar observation ranges overlap as the joint observation area based on the front-side dual-SAR joint observation geometric model diagram includes: Based on the geometric model diagram of the joint observation of the front-side dual-SAR, the two radars with the front-side observation mode are fixed at the front and rear positions on the same side of the vehicle platform. The front radar and the rear radar are respectively 、 express; Front and rear radars along Axis direction and along The axis is in the same position only along the There is spacing in the axial direction The radar observation range is represented by an ellipse. The area where the front and rear radar observation ranges overlap is called the joint observation area.

3. The SAR radar velocity estimation method based on overlapping fields of view according to claim 1, characterized in that: The step of controlling the radar to transmit linear frequency modulation pulses to the detection area based on the defined joint observation area and intercepting radar pulse information of the joint observation area includes: Based on the designated joint observation area, the radar is controlled to transmit linear frequency modulation pulses to the detection area. The signals are reflected by the target and then received by the radar. Acquire front and rear radar data and vehicle-mounted platform speed data, and analyze the synthetic aperture length of the joint observation based on the joint observation area.

4. The SAR radar velocity estimation method based on overlapping fields of view according to claim 1, characterized in that: The step of constructing a SAR joint velocity similarity matrix based on overlapping sites based on the joint observation area and the intercepted radar pulse information of the joint observation area includes: Based on the joint observation area and the intercepted radar pulse information of the joint observation area, a SAR joint velocity similarity matrix based on overlapping sites is constructed. ; SAR joint velocity similarity matrix The rows and columns correspond to the front radar speed and rear radar speed The initial discretization interval is set to 1m / s; Through and Discretize it, divide its value range into a finite set of discrete points, and combine all the speeds as element indexes into matrices; For each element in the matrix , by using SAR imaging algorithms, using Process the front radar echo data and get the front imaging matrix as ;use Process the rear radar echo data and obtain the rear imaging matrix: , calculate the similarity and fill the result into the corresponding position of the matrix.

5. The SAR radar velocity estimation method based on overlapping fields of view according to claim 1, characterized in that: The step of controlling the determined SAR radar velocity estimation interval to be gradually narrowed and updating the constructed joint velocity similarity matrix includes: In constructing the joint velocity similarity matrix Find the row and column values ​​corresponding to the maximum value, reduce the discretization interval to one tenth of the original, and take the row and column values ​​before and after the corresponding maximum value. Speed ​​value, get the new speed ; For each element in the matrix , using SAR imaging algorithms and updated speed , calculate the similarity and fill the result into the joint speed similarity matrix Corresponding position, the joint velocity similarity matrix to update.

6. The SAR radar velocity estimation method based on overlapping fields of view according to claim 1, characterized in that: The step of repeating the above steps, estimating the SAR radar velocity multiple times using the updated joint velocity similarity matrix until the estimated SAR radar velocity reaches a predetermined accuracy, and outputting a final SAR radar velocity estimation value comprises: Through the joint velocity similarity matrix , perform SAR radar velocity estimation three times until the estimated SAR radar velocity reaches a predetermined accuracy, for example, the accuracy reaches 0.01 m / s; then output the final SAR radar velocity estimation value.

7. The SAR radar velocity estimation method based on overlapping fields of view according to claim 1, characterized in that: The step of repeating the above steps, estimating the SAR radar velocity multiple times using the updated joint velocity similarity matrix until the estimated SAR radar velocity reaches a predetermined accuracy, and outputting a final SAR radar velocity estimation value comprises: Repeat the above steps and combine the speed similarity matrix , perform SAR radar velocity estimation three times until the estimated SAR radar velocity reaches a predetermined accuracy, for example, the accuracy reaches 0.01 m / s; then output the final SAR radar velocity estimation value; The accuracy of the first stage is 1m / s, the second stage is accurate to 0.1m / s, and the third stage is accurate to 0.01m / s, and the final SAR radar velocity estimate is output.

8. A SAR radar velocity estimation device based on overlapping fields of view, characterized in that: The device comprises: The joint observation area delineation module is used to delineate the area where the front and rear radar observation ranges overlap as the joint observation area based on the geometric model diagram of the front-side and side-view dual SAR joint observation; An interception module is used to control the radar to transmit linear frequency modulation pulses to the detection area based on the demarcated joint observation area, and intercept radar pulse information in the joint observation area; a matrix construction module, configured to construct a SAR joint velocity similarity matrix based on the overlapping scene based on the joint observation area and the intercepted radar pulse information of the joint observation area; wherein the rows and columns of the SAR joint velocity similarity matrix correspond to discrete values ​​of the front radar velocity and the rear radar velocity, respectively; the front radar velocity and the rear radar velocity are imaged according to the radar velocities indexed by the rows and columns, and the similarity of the two generated images is calculated and filled into the corresponding positions of the matrix; The speed estimation module is used to estimate the SAR radar speed based on the joint speed similarity matrix. The row and column values ​​corresponding to the maximum value in the joint speed similarity matrix are used as the preliminary estimated speeds of the front and rear radars, respectively, to determine the SAR radar speed estimation interval. The matrix update module is used to control the gradual reduction of the determined SAR radar velocity estimation interval and update the constructed joint velocity similarity matrix; The repeated estimation and final output module is used to repeat the above steps, estimate the SAR radar speed multiple times through the updated joint velocity similarity matrix until the estimated SAR radar speed reaches a predetermined accuracy, and output the final SAR radar speed estimation value.

9. An intelligent terminal, characterized in that: The device comprises a memory and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by one or more processors, and the one or more programs include being used to execute the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that When the instructions in the storage medium are executed by a processor of an electronic device, the electronic device is enabled to execute the method according to any one of claims 1 to 7.

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