Consistency Imaging Method and System Based on High-Order Fitting of Fourier Series

Abstract

The present invention discloses a consistency imaging method and system based on high-order fitting of Fourier series, belonging to the technical fields of optical and radar imaging. The method includes converting the SAR wavenumber domain imaging result in the overlapping field of view to the pixel coordinate system where the optical photo is located according to the overlapping field of view of the optical camera and the SAR sensor, and establishing the theoretical relationship between the pixel deviation of the optical photo and the SAR wavenumber domain imaging result in the range direction and the azimuth direction and the position deviation of the SAR wavenumber domain imaging result in each direction; fitting the non-linear azimuth pixel deviation between the optical camera and the SAR sensor under the common aperture system into the form of a Fourier high-order series related to the azimuth position, and compensating for the non-linear imaging position deviation in any azimuth direction during the SAR wavenumber domain imaging process according to the theoretical relationship to achieve the consistency imaging registration of the optical and SAR. The present invention breaks through the traditional situation of separate imaging and registration and has higher processing efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical fields of optics and radar imaging, and particularly relates to a consistency imaging method and system based on high-order fitting of Fourier series. Background Art

[0002] Combining a high-resolution optical camera and a synthetic aperture radar (SAR) sensor for all-weather and all-time imaging, and using the advantages of both for complementary imaging is a current research trend in the field of remote sensing images. After analysis and interpretation, multi-source images can be used in fields such as target recognition and detection. Existing remote sensing systems mostly obtain optical and SAR images in a non-common aperture system, and the images after registration and fusion processing are widely used in military and civilian fields. In the field of remote sensing, image domain registration methods are mostly adopted. Image domain registration methods based on feature points, regions, deep learning, etc. are complex to operate. The imaging data of heterogeneous loads obtained by non-common aperture systems at multiple angles, multiple regions, and multiple times requires improvement in the accuracy and efficiency of image domain registration.

[0003] There are imaging mechanism and radiation differences between optical cameras and SAR sensors. The acquisition of heterogeneous data by non-common aperture systems has inconsistencies in time, angle, and region, which will make the optical and SAR image domain registration process complex and difficult to achieve online real-time processing. Therefore, to solve the fundamental problems existing in heterogeneous image registration and study a consistency imaging method under a common aperture system, compensating for the imaging deviation between the SAR imaging process and the optical photo has important research significance and value, which can improve the efficiency and accuracy of heterogeneous image processing. Summary of the Invention

[0004] To solve the above technical problems, the present invention provides a consistency imaging method and system based on high-order fitting of Fourier series. The adopted common aperture system can acquire consistent imaging data of heterogeneous loads, combining active and passive remote sensing means, which can not only obtain synchronous phase consistency imaging data for cross-optical and electrical frequency domain remote sensing information, but also compensate for the imaging position deviation that causes optical / SAR pixel deviation during the SAR imaging process, achieving the purpose of sub-pixel registration of SAR imaging and optical photos, avoiding many problems existing in the heterogeneous image registration process, and improving the efficiency of image registration. At the same time, a wavenumber domain ( ) imaging algorithm with good performance in imaging efficiency and accuracy is adopted, which can avoid the problems of large computational complexity and low computational efficiency of the time-domain BP imaging algorithm.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A consistency imaging method based on high-order fitting of Fourier series, the method comprising:

[0007] Step 1: According to the coaxial geometric configuration in the common aperture system of the optical camera and the SAR sensor, obtain the overlapping field of view of the optical camera and the SAR sensor, convert the SAR wavenumber domain imaging result in the overlapping field of view to the pixel coordinate system where the optical photo is located, and establish the theoretical relationship between the pixel deviations of the optical photo and the SAR wavenumber domain imaging result in the range direction and azimuth direction and the position deviations of the SAR wavenumber domain imaging result in each direction;

[0008] Step 2: Fit the non-linear azimuth pixel deviation between the optical camera and the SAR sensor in the common aperture system into the form of a Fourier high-order series related to the azimuth position. According to the theoretical relationship, compensate for the non-linear imaging position deviation in any azimuth direction during the SAR wavenumber domain imaging process to achieve consistent imaging registration under the optical and SAR common aperture system.

[0009] On the other hand, the present invention also provides a consistent imaging system based on high-order Fourier series fitting, including:

[0010] A relationship acquisition unit, configured to obtain the overlapping field of view of the optical camera and the SAR sensor according to the coaxial geometric configuration in the common aperture system of the optical camera and the SAR sensor, convert the SAR wavenumber domain imaging result in the overlapping field of view to the pixel coordinate system where the optical photo is located, and establish the theoretical relationship between the pixel deviations of the optical photo and the SAR wavenumber domain imaging result in the range direction and azimuth direction and the position deviations of the SAR wavenumber domain imaging result in each direction;

[0011] A compensation registration unit, configured to fit the non-linear azimuth pixel deviation between the optical camera and the SAR sensor in the common aperture system into the form of a Fourier high-order series related to the azimuth position. According to the theoretical relationship, compensate for the non-linear imaging position deviation in any azimuth direction during the SAR wavenumber domain imaging process to achieve consistent imaging registration under the optical and SAR common aperture system.

[0012] In the third aspect, the present invention provides an electronic device, including: one or more processors; a memory for storing one or more programs; wherein, when the one or more programs are executed by the one or more processors, the one or more processors implement the foregoing consistent imaging method based on high-order Fourier series fitting.

[0013] In the fourth aspect, the present invention provides a computer-readable storage medium, on which executable instructions are stored, and when the instructions are executed by a processor, the processor can implement the foregoing consistent imaging method based on high-order Fourier series fitting.

[0014] The beneficial effects of the present invention are as follows:

[0015] The present invention adopts a relatively accurate An imaging method, with higher computational efficiency than the time-domain BP imaging algorithm, can be used for real-time processing in engineering to reduce the computational amount; taking an accurate optical photo as a reference benchmark, constructing the theoretical relationship between the pixel deviations in each direction of the optical / SAR and the imaging position deviation in the pixel coordinate system; imaging flat multi-point targets at long distances, without compensating for the range-direction pixel deviation directly at the sub-pixel level; performing Fourier high-order series fitting on the non-linear azimuth-direction pixel deviation, and according to the theoretical relationship between the pixel deviation and the imaging position deviation, performing consistency imaging compensation in any azimuth direction during the imaging process to achieve the purpose of registering the SAR imaging with the optical photo, realizing the co-aperture consistency imaging processing of the optical / SAR at the sub-pixel level in both the range direction and the azimuth direction, breaking through the traditional situation of separate imaging and registration, and having higher processing efficiency. Description of the Drawings

[0016] Figure 1 This is the flowchart of a consistency imaging method based on Fourier series high-order fitting according to the present invention;

[0017] Figure 2 This is a schematic diagram of the overlapping field-of-view geometric configuration of an optical camera and an SAR sensor provided by the present invention under an airborne co-aperture system. Detailed Embodiments

[0018] The present invention will be further described below with reference to the drawings and embodiments.

[0019] The present invention proposes a consistency imaging method based on Fourier series high-order fitting. Starting from the respective imaging mechanisms of the optical / SAR, using the spectral splitting and frequency division technology, the optical path and microwaves pass through the same aperture at the same time, obtaining heterologous data for co-aperture consistency imaging processing of the optical / SAR in the same area. Constructing the theoretical relationship between the pixel deviation between the optical photo and the SAR imaging result under the co-aperture and the imaging position deviation in their respective directions in the pixel coordinate system where the optical photo is located, enabling the SAR imaging result and the optical photo to be directly and automatically registered under the co-aperture system, breaking through the separation of traditional imaging and registration, avoiding the complex processing flow of image-domain registration, and achieving the purpose of efficient processing.

[0020] As Figure 1 shown, the flowchart of the consistency imaging method based on Fourier series high-order fitting according to the present invention is given, which specifically includes:

[0021] Step 1: According to the coaxial geometric configuration in the common-aperture system of the optical camera and the SAR sensor, obtain the overlapping field of view of the optical camera and the SAR sensor. Convert the SAR wavenumber domain imaging result in the overlapping field of view to the pixel coordinate system where the optical photo is located, and establish the theoretical relationship between the pixel deviations of the optical photo and the SAR imaging result in the range direction and the azimuth direction and the imaging position deviations in each direction of the SAR wavenumber domain.

[0022] Step 2: Conduct imaging simulation on multi-point targets in the overlapping field of view of the optical camera and the SAR. Both the simulation and the theoretical calculation show that the pixel deviation in the range direction does not need to be compensated and is directly at the sub-pixel level. The non-linear pixel deviation in the azimuth direction between the optical camera and the SAR in the common-aperture system is fitted into the form of a Fourier high-order series related to the azimuth position. According to the theoretical relationship between the pixel deviation and the imaging position deviation in Step 1, compensate the non-linear imaging position deviation in any azimuth direction during the SAR wavenumber domain imaging process to achieve consistent imaging registration in the optical and SAR common-aperture system, so that the pixel deviations in the range direction and the azimuth direction are both at the sub-pixel level.

[0023] The principle of the method is as follows:

[0024] The optical / SAR common-aperture consistent imaging method needs to construct a consistent imaging model for heterogeneous data. The optical remote sensing frame camera obtains an optical image through instantaneous exposure. Using the central projection imaging principle, ideally, the object point, the camera optical center, and the image point are collinear. The SAR sensor obtains the SAR image through signal processing during the synthetic aperture time. It can only actively image in a side-looking manner. Therefore, in the common-aperture system, the optical camera needs to tilt for imaging. Taking the precise photo taken by the tilted optical camera as a reference and combining the system parameters of the SAR sensor, calculate the overlapping field of view area of the optical camera and the SAR sensor in the common-aperture system.

[0025] Through the optical central projection imaging principle, convert the SAR wavenumber domain imaging result in the overlapping field of view to the pixel coordinate system where the optical photo is located by principles such as the collinearity equation and coordinate transformation, and construct the relationship between the pixel deviation between the optical camera / SAR imaging results and the imaging position deviations in each direction of the SAR wavenumber domain. Conduct multi-point target imaging simulation in the overlapping field of view and combine with theoretical calculation. The pixel deviation in the range direction is already at the sub-pixel level and does not need to be compensated; some pixel deviations in the azimuth direction exceed the sub-pixel level. Fit the non-linear pixel deviation in the azimuth direction into the form of a Fourier high-order series related to the azimuth position. According to the theoretical relationship between the pixel deviation and the imaging position deviation, effectively compensate the imaging position deviations in each azimuth direction during the SAR wavenumber domain imaging process, so that both the range direction and the azimuth direction reach sub-pixel level registration, achieving the purpose of matching the SAR imaging with the optical photo, that is, the realization of the optical / SAR consistent imaging method based on high-order fitting of Fourier series.

[0026] Specifically, in the airborne common aperture system, the optical camera adopts the area array push-broom imaging method, and multiple accurate optical photos are obtained through instantaneous exposure. At the moment when the area array CCD aerial camera takes a picture, all the pixels in the optical photo are formed at the same time. Each optical photo conforms to the central projection law, and the image point, the optical center of the camera, and the object point are on the same straight line. One image corresponds to a set of attitude parameters. An imaging equation is established according to the principle of central optical projection, and then the mutual conversion between three-dimensional object points and two-dimensional image points is carried out.

[0027] According to the relationship between the exposure rate of the optical camera and the SAR synthetic aperture time, taking the optical photo corresponding to the most central moment of each synthetic aperture of the SAR sensor as the reference benchmark, and based on system parameters such as the field of view angle of the optical camera, the beam width of the SAR sensor, the flight altitude of the aircraft, and the nearest slant range, the overlapping field of view area of the optical camera and the SAR sensor is calculated. The imaging result is converted to the pixel coordinate system where the optical photo is located, and the theoretical relationship between the pixel deviation of the two and the imaging position deviation in each direction of the SAR is constructed.

[0028] The SAR imaging result is converted from the north-east-down coordinate system ( ) to the camera coordinate system ( ) and then to the pixel coordinate system ( ). Figure 2 is the schematic diagram of the overlapping field of view geometric configuration of the optical camera and the SAR sensor in the airborne common aperture system. is the flight altitude of the aircraft. There are corresponding conversion relationships between different coordinate systems. The coordinates of the ideal flat ground target in the north-east-down coordinate system and the image point coordinates in the pixel coordinate system have the following relationship:

[0029] ,

[0030] where is the translation amount to be determined between the origin of the north-east-down coordinate system and the origin of the camera coordinate system. Among them, is the translation amount in the azimuth direction, is the flight altitude of the aircraft, and the superscript ′ represents the matrix transpose expression in mathematics. is the internal parameter matrix of the camera, is the external parameter matrix of the camera, is the projection size of the object point under the axis of the camera coordinate system, is the homogeneous coordinate expression of the image point in the pixel coordinate system. The specific form of .

[0031] is the camera focal length, is the pixel size of the imaging system, are the pixel coordinates of the principal image point.

[0032] The specific form of is the rotation matrix about the axis of the north-east-earth coordinate system, is the roll angle of rotation, is the rotation matrix about the axis of the north-east-earth coordinate system, and the rotation angle is 90°.

[0033] ,

[0034] to obtain the ideal flat ground target to the image point coordinates in the pixel coordinate system :

[0035] ,

[0036] Similarly, the SAR imaging result is converted to the image point coordinates in the pixel coordinate system , where , are the imaging position deviations of the SAR imaging result in the range direction and azimuth direction:

[0037] ,

[0038] Subtracting the above two equations gives the pixel deviation formulas of the optical camera and SAR sensor in the range direction and azimuth direction under the airborne co-aperture system:

[0039] ,

[0040] ,

[0041] It can be seen that the range-direction pixel deviation is only related to the imaging position deviation of the SAR imaging result in the range direction, and the azimuth-direction pixel deviation is related to the imaging position deviations , of the SAR imaging result in the range direction and azimuth direction.

[0042] Qualitative analysis shows that the range-direction coordinate of the multi-point target is much larger than the imaging position deviation of the SAR imaging result in the range direction, that is: ;

[0043] Therefore, the pixel deviations of optics and SAR in the range and azimuth directions under the common-aperture system are approximated to obtain the theoretical relationship between the pixel deviation and the imaging position deviation in each direction of SAR. The pixel deviations in the range and azimuth directions are only related to the imaging position deviations in their respective directions:

[0044] ,

[0045] ,

[0046] At the present stage, the SAR imaging algorithm has been developed and matured day by day. The imaging method is a relatively accurate imaging algorithm in the frequency domain algorithm, with high imaging efficiency and accuracy. The SAR imaging system performs imaging processing on the received echo data. The basic steps are as follows: perform two-dimensional FFT on the echo signal, perform uniform compression and Stolt interpolation at the reference distance, and IFFT the two-dimensional frequency-domain signal to the time domain to obtain the target imaging result. According to the relationship between the aforementioned optical and SAR pixel deviations and the imaging position deviations, and the time-shift characteristics of the Fourier transform, after Stolt interpolation, the imaging position deviations in the range and azimuth directions are compensated respectively in the frequency domain to achieve pixel deviation compensation between optics and SAR.

[0047] Considering the requirements of SAR long-distance imaging and high bandwidth, high penetration power, and strong anti-interference ability, perform long-distance simulation imaging on multi-point targets under the overlapping field of view of the optical camera and SAR. The pixel deviations in the range direction of the optical photo and the SAR imaging result are both at the sub-pixel level, and can also be calculated through the aforementioned theoretical relationship. The imaging position deviation in the range direction corresponding to the sub-pixel level deviation in the range direction is close to the high resolution in the range direction. Therefore, there is no need to perform range direction compensation, and direct sub-pixel level range registration can be achieved. The fluctuation trends of the imaging position deviation and the pixel deviation in the azimuth direction are the same, showing an irregular and non-linear trend with a small oscillation amplitude. The imaging deviation in the same azimuth direction is the same, and the pixel deviation in the azimuth direction of some target points exceeds the sub-pixel unit and needs to be compensated. Fit the non-linear pixel deviation in the azimuth direction to the form of a Fourier high-order series related to the azimuth position :

[0048] ,

[0049] where is the position of each point in the azimuth direction, is the order of the Fourier series, , , , are all constant parameters of the fitting formula. The coefficient between the optical / SAR pixel deviation in the azimuth direction and the SAR imaging position deviation is: , related to the position coordinates in the range direction where the target is located For quantitative calculation, in the optical / SAR overlapping field of view, , the differences between its maximum value, minimum value and mean value are all within order of magnitude. Therefore, the mean value is regarded as an approximate constant coefficient to simplify the compensation process.

[0050] According to the theoretical relationship between the pixel deviation and the imaging position deviation in step 1, during the imaging process, compensate for the non-linear imaging position deviation in any azimuth direction to achieve the co-aperture consistent imaging registration of optics and SAR, so that the pixel deviations in the range direction and azimuth direction are both at the sub-pixel level. The SAR imaging azimuth imaging position deviation compensation factor is expressed as:

[0051] ,

[0052] where, is the azimuth frequency, is the flight speed of the aircraft.

[0053] Based on the differences and connections between the imaging geometries of the optical camera and the SAR sensor, the present invention takes the precise optical photo corresponding to the center moment of each synthetic aperture of the SAR as the reference benchmark. Under the overlapping field of view of the optical camera and the SAR sensor, the relatively precise imaging result is converted to the pixel coordinate system where the optical photo is located. The range-direction pixel deviation is directly at the sub-pixel level. According to the relationship between the pixel deviation and the imaging position deviation deduced theoretically, during the imaging process, the azimuth imaging position deviation of any azimuth non-linearity is obtained from the azimuth non-linear pixel deviation obtained by fitting, and then compensation is performed during the imaging process to achieve azimuth consistent imaging processing. According to the azimuth non-linear pixel deviation in the form of Fourier high-order series obtained by fitting, this method can obtain the imaging position deviation in any azimuth direction under the overlapping field of view. The imaging position deviations in the same azimuth direction are the same, which can simplify the calculation amount of the consistent imaging compensation process. This method does not require complex registration processing in the image domain, improving the efficiency of image processing.

[0054] On the other hand, the present invention provides a consistent imaging system based on Fourier series high-order fitting, and each module included therein can implement each step of the foregoing method. Specifically, it includes:

[0055] A relationship acquisition unit, configured to obtain an overlapping field of view of an optical camera and a SAR sensor according to a coaxial geometric configuration in a co-aperture system of the optical camera and the SAR sensor, convert the SAR wavenumber domain imaging result in the overlapping field of view to the pixel coordinate system where the optical photo is located, and establish a theoretical relationship between the pixel deviations of the optical photo and the SAR wavenumber domain imaging result in the range direction and the azimuth direction and the position deviations of the SAR wavenumber domain imaging result in each direction.

[0056] A compensation and registration unit, configured to fit the non-linear azimuth pixel deviation between the optical camera and the SAR sensor in the co-aperture system into a form of a Fourier high-order series related to the azimuth position, and compensate for the non-linear imaging position deviation in any azimuth direction during the SAR wavenumber domain imaging process according to the theoretical relationship, so as to achieve consistent imaging registration under the optical and SAR co-aperture system.

[0057] In a third aspect, the present invention provides an electronic device, including: one or more processors; a memory for storing one or more programs; wherein, when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the foregoing consistency imaging method based on high-order fitting of Fourier series.

[0058] In a fourth aspect, the present invention provides a computer-readable storage medium, on which executable instructions are stored, and when the instructions are executed by a processor, the processor is enabled to implement the foregoing consistency imaging method based on high-order fitting of Fourier series.

[0059] The specific embodiments described above further elaborate on the purpose, technical solution and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A consistency imaging method based on Fourier series high-order fitting, characterized in that: The method comprises: Step 1: According to the coaxial geometric configuration of the optical camera and the SAR sensor under the common aperture system, the overlapping field of view of the optical camera and the SAR sensor is obtained, the SAR wave number domain imaging result under the overlapping field of view is converted to the pixel coordinate system where the optical photo is located, and the theoretical relationship between the pixel deviation of the optical photo and the SAR wave number domain imaging result in the range and azimuth directions and the position deviation of the SAR wave number domain imaging result in each direction is established; Step 2: Fitting the nonlinear azimuth pixel deviation between the optical camera and the SAR sensor in the common aperture system into the form of a Fourier high-order number related to the azimuth position, and compensating for the nonlinear imaging position deviation in any azimuth direction in the SAR wavenumber domain imaging process according to the theoretical relationship, so as to achieve consistent imaging registration in the optical and SAR common aperture system; specifically comprising: Direction to nonlinear pixel deviation Fitting to the azimuth position The relevant Fourier higher order form is: ， in, is the position of each point in the azimuth direction, is the order of the Fourier series, , , , is the constant parameter of the fitting formula; The SAR imaging azimuth imaging position deviation compensation factor is expressed as: , is the azimuth frequency, is the aircraft's flying speed, is the coefficient between the optical SAR azimuth pixel deviation and the SAR imaging position deviation; According to the theoretical relationship, During the imaging process, the nonlinear imaging position deviation in any azimuth is compensated based on the compensation factor to achieve consistent imaging registration of optical and SAR common apertures.

2. The consistent imaging method based on Fourier series high-order fitting according to claim 1, characterized in that: Obtaining the overlapping field of view of the optical camera and the SAR sensor in the common aperture system in step 1 includes: using the central projection imaging principle, based on the collinearity of the object point, the camera optical center, and the image point, taking the tilted imaging optical photograph as a reference, and combining the system parameters of the SAR sensor to calculate the overlapping field of view area of ​​the optical camera and the SAR sensor in the common aperture system.

3. The consistent imaging method based on Fourier series high-order fitting according to claim 1, characterized in that: The step 1 of converting the SAR wavenumber domain imaging result under the overlapping field of view into the pixel coordinate system where the optical photo is located includes: Coordinates of the target based on an ideal flat ground in the north-east coordinate system Image point coordinates in pixel coordinate system The following relationship exists: ， In the formula, is the amount of translation between the origin of the north-east coordinate system and the origin of the camera coordinate system, where is the amount of translation to be made in azimuth, is the flight altitude of the aircraft, and the superscript ' represents the matrix transpose expression in mathematics. is the camera internal parameter matrix, is the camera extrinsic parameter matrix, is the object point in the camera coordinate system The size of the projection under the axis, It is the homogeneous coordinate expression of the image point in the pixel coordinate system; Calculate ideal flat ground target Convert the pixel coordinates to the pixel coordinate system : ， In the formula, is the camera focal length, is the pixel size of the imaging system, is the pixel coordinate of the image principal point, is the roll angle of rotation; Computing SAR imaging results Convert the pixel coordinates to the pixel coordinate system ,in , is the imaging position deviation of the SAR imaging result in the range and azimuth directions: 。 4. The consistent imaging method based on Fourier series high-order fitting according to claim 3, characterized in that: The camera intrinsic parameter matrix The specific form is: , the camera extrinsic parameter matrix The specific form is: , It is a coordinate system around the north east The rotation matrix of the axis, It is a coordinate system around the north east The rotation matrix of the axis, with a rotation angle of 90°.

5. The consistent imaging method based on Fourier series high-order fitting according to claim 3, characterized in that: The theoretical relationship between the pixel deviations of the optical photograph and the SAR wavenumber domain imaging results in the range and azimuth directions and the position deviations of the SAR wavenumber domain imaging results in each direction established in step 1 includes: The formula for calculating the pixel deviation of the optical camera and SAR sensor in the range and azimuth directions in the common aperture system is: ， ， The pixel deviation formulas of optics and SAR in the range and azimuth directions under the common aperture system are approximated, and the theoretical relationship between the pixel deviation and the SAR imaging position deviation in each direction is obtained: ， 。 6. The consistent imaging method based on Fourier series high-order fitting according to claim 5, characterized in that: The pixel deviation formulas for the optical and SAR in the range and azimuth directions under the common aperture system are approximated by: Much larger than the imaging position deviation of SAR imaging results in the range direction ,Right now: Make an approximation.

7. A consistency imaging system based on Fourier series high-order fitting, characterized in that: include: A relationship acquisition unit is used to obtain the overlapping fields of view of the optical camera and the SAR sensor according to the coaxial geometric configuration of the optical camera and the SAR sensor under the common aperture system, convert the SAR wave number domain imaging results under the overlapping fields of view into the pixel coordinate system where the optical photograph is located, and establish a theoretical relationship between the pixel deviations of the optical photograph and the SAR wave number domain imaging results in the range and azimuth directions and the position deviations of the SAR wave number domain imaging results in each direction; A compensation registration unit is used to fit the nonlinear azimuth pixel deviation between the optical camera and the SAR sensor in the common aperture system into the form of a Fourier high-order number related to the azimuth position, and according to the theoretical relationship, compensate for the nonlinear imaging position deviation in any azimuth direction in the SAR wave number domain imaging process, so as to achieve consistent imaging registration in the optical and SAR common aperture system; Specifically include: Direction to nonlinear pixel deviation Fitting to the azimuth position The relevant Fourier higher order form is: ， in, is the position of each point in the azimuth direction, is the order of the Fourier series, , , , is the constant parameter of the fitting formula; The SAR imaging azimuth imaging position deviation compensation factor is expressed as: , is the azimuth frequency, is the aircraft's flying speed, is the coefficient between the optical SAR azimuth pixel deviation and the SAR imaging position deviation; According to the theoretical relationship, During the imaging process, the nonlinear imaging position deviation in any azimuth is compensated based on the compensation factor to achieve consistent imaging registration of optical and SAR common apertures.

8. An electronic device, characterized in that: include: one or more processors; A memory for storing one or more programs; Wherein, when one or more programs are executed by the one or more processors, the one or more processors implement the consistency imaging method based on Fourier series high-order fitting as described in any one of claims 1-6.

9. A computer-readable storage medium, characterized in that: Executable instructions are stored thereon, and when the instructions are executed by the processor, the processor can implement the consistent imaging method based on Fourier series high-order fitting as described in any one of claims 1-6.

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