CN109752697A - A kind of wide angle scanning Sliding spotlight SAR satellite system relative radiation performance measurement method - Google Patents
A kind of wide angle scanning Sliding spotlight SAR satellite system relative radiation performance measurement method Download PDFInfo
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Abstract
It exposes thoroughly Sliding spotlight SAR satellite system relative radiation performance measurement method the invention discloses one kind, which comprises the uniform scene of selective scattering is as imaging region；Imaging and range attenuation correction are carried out to echo data, obtain haplopia complex image data；It rejects in image and significantly scatters Nonuniform Domain Simulation of Reservoir, to eliminate its adverse effect to subsequent relative radiation performance measurement；Image is smoothed using certain rectangular window, reduces influence of noise, obtains magnitude image；It is averaging processing using the multiple image of identical wave position, further decreases influence of noise；According to the orientation scanning range of radar and distance to radar parameters such as beam angles, the corresponding azimuth of the smooth each pixel of amplitude image and downwards angle of visibility are determined；Using azimuth and downwards angle of visibility as variable, even-order Two-dimensional Surfaces fitting of a polynomial is carried out to smoothed out magnitude image, obtains the relative radiation performance of system.Using technical solution of the present invention, the high-acruracy survey for the Sliding spotlight SAR satellite system relative radiation performance that exposes thoroughly can be efficiently obtained as a result, can be used for the relative detector calibration of system, improves picture quality.
Description
Technical field
The invention belongs to remote sensing satellite technical fields, in particular to satellite-borne synthetic aperture radar radiant correction technology.
Background technique
Synthetic aperture radar (SAR) satellite is a kind of active remote sensing equipment, can round-the-clock, all weather operations, obtain high score
Resolution ground scene SAR image.Sliding pack is a kind of novel synthetic aperture radar operating mode, by controlling antenna side
Position increases the orientation coherent accumulation time in the movement speed on ground to wave beam, to improve the resolution ratio of orientation.With biography
The stripmap SAR of system is compared, and other than distance caused by modulation of the distance to antenna radiation pattern is uneven to radiation, slides pack
There are orientation antenna radiation pattern performance changes in orientation scanning by SAR, so as to cause there are the radiation of distinctive orientation is uneven
Even property.Due to scanning more than orientation wave position and along orientation in the radar course of work, directional diagram inflight measurement is difficult,
It is difficult to carry out theoretical calculation to relative radiation performance based on in-orbit pattern measurement result and compensate.How two are accurately obtained
Relative radiation performance is tieed up, is before Sliding spotlight SAR satellite system realizes high-precision relative detector calibration, improves picture quality
It mentions.
Summary of the invention
High, wide angle scanning Sliding spotlight SAR satellite system phase easy to implement that it is an object of the present invention to provide a kind of precision
To radiance measurement method, it is the high-precision relative detector calibration of wide angle scanning Sliding spotlight SAR satellite, promotes image spoke
It penetrates quality and basic data is provided.
The technical solution of the present invention is as follows:
A kind of wide angle scanning Sliding spotlight SAR satellite system relative radiation performance measurement method, comprising the following steps:
A. imaging region is chosen, after system performance tuning is completed in SAR satellite and its Ground Data Processing System, selection
The uniform scene of radar raster-displaying is as imaging region.
B. imaging and range attenuation correction, carry out imaging to imaging region echo, and decaying of adjusting the distance carries out
Correction obtains haplopia complex pattern IX×Y, wherein X is the orientation pixel number of image, and Y is the distance of image to pixel number.
C. nonisotropic scattering region is rejected, and is rejected in image and is significantly scattered Nonuniform Domain Simulation of Reservoir, to eliminate it to subsequent phase
To the adverse effect of radiance measurement.
D. image is smoothed using certain rectangular window, reduces influence of noise, obtain magnitude image A；Root
It is estimated according to relative radiation fluctuation characteristic and noise level, while comprehensively considering following two factor, first is that relative radiation
The holding of energy curved surface characteristic, second is that the smooth effect of noise, the specific size for determining window.
E. each pixel A of smooth amplitude image A is determined according to radar parameterxyCorresponding azimuth angle alpha and downwards angle of visibility β,
The orientation scanning range and distance that the radar parameter includes radar are to beam angle.
F. using azimuth angle alpha and downwards angle of visibility β as variable, Two-dimensional Surfaces fitting of a polynomial is carried out to smoothed out magnitude image A,
With the relative radiation performance Two-dimensional Surfaces A ' after being fitted, fitting order is even number.
The present invention provides a kind of wide angle scanning Sliding spotlight SAR satellite relative radiation performance measurement methods, choose radar
The uniform scene of back scattering is smoothed observation area image as observation area, using smoothing windows, reduces noise shadow
It rings, 2-d polynomial fitting is carried out, it can be achieved that wide angle scanning Sliding spotlight SAR system relative radiation to smoothed out image
Can high-acruracy survey, this method is not necessarily to each azimuth scan angle antenna radiation pattern of radar, and measurement accuracy and high-efficient can be used for
Big azimuth scan angle Sliding spotlight SAR high-precision relative detector calibration, promotes image radiation quality.
Detailed description of the invention
Fig. 1 is a kind of wide angle scanning Sliding spotlight SAR satellite system relative radiation performance measurement method provided by the invention
Flow diagram.
Fig. 2 is the opposite spoke of certain Sliding spotlight SAR satellite system obtained using the method for the present invention using tropical rain forest region
Penetrate performance measurements.
Specific embodiment
The basic idea of the invention is that being observation area using homogenous diffusion scene, on the basis of removal Nonuniform Domain Simulation of Reservoir
On, influence of noise is reduced using smoothing windows, the relative radiation feature measurement of system is obtained using the method that 2-d polynomial is fitted
As a result,
Below by the drawings and specific embodiments, the present invention is described in further detail.
The present invention gives a kind of wide angle scanning Sliding spotlight SAR satellite system relative radiation performance measurement method, processes
As shown in Fig. 1, method includes the following steps:
Step 1: imaging region is chosen.System is completed in Synthetic Aperture Radar satellite and its Ground Data Processing System
After Performance tuning, select the uniform scene of radar raster-displaying as imaging region.
In specific selection, tropical rain forest is the uniform scene of ideal radar scattering, and scattering properties becomes with incidence angle
Change small uniform.In addition, for distance to the smooth for the lesser system of observation swath, within the scope of small incident
Also it can be used as observation area.
Step 2: imaging and range attenuation correction.Imaging is carried out to the echo data of imaging region, specifically at
As rising and falling to eliminate in observation swath due to being radiated caused by oblique distance difference, the decaying that needs to adjust the distance carries out school in processing
Just, updating formula is as follows,
Wherein, I 'X×YFor the haplopia complex pattern before range attenuation correction, IX×YScheme again for the haplopia after range attenuation correction
Picture, X are the orientation pixel number of image, and Y is the distance of image to pixel number；R0For what is chosen in range attenuation correction
With reference to oblique distance, it is usually chosen for scene center oblique distance；R is the corresponding oblique distance value of each range gate.
Step 3: it rejects in nonisotropic scattering region.For tropical rain forest region, due to river, rainfall ponding
Etc. the mankind's activities such as natural phenomenas and trees felling, can all cause the presence in nonisotropic scattering region, implement subsequent behaviour
Before work, inconsistent region will be scattered with main body by, which needing, is rejected, to eliminate its adverse effect to relative radiation performance measurement.
Step 4: being smoothed image using certain rectangular window, reduces influence of noise.
In concrete operations, the specific formula for calculation of smoothed out magnitude image A is as follows,
Wherein, the orientation and distance that 2m+1,2n+1 are respectively smoothing windows are to pixel number.The specific value of m, n have two
The factor of a aspect in relation to: from the angle for keeping relative radiation performance surface shape, value is the smaller the better；From to reduction
The angle of influence of noise is set out, and value is the bigger the better.Need to comprehensively consider the two factors in specific operation, according to right
Relative radiation fluctuation characteristic and noise level are estimated, the specific size for determining window.
Step 5: repeatedly observation is average, reduces influence of noise.
Specifically, the noise of image is relatively high if imaging region uniformity is poor, can smoothly be located in single image
On the basis of reason, it is averaging processing using the multiple image of identical wave position, further decreases influence of noise,
Step 6: according to the orientation scanning range of radar and distance to radar parameters such as beam angles, map of magnitudes is determined
As each pixel A of AxyCorresponding azimuth angle alpha and downwards angle of visibility β,
α∈[-αmax,αmax]
β∈[-βmax,βmax]
αmaxFor the half of Sliding spotlight SAR azimuth scan range, βmaxIt is distance to the half of beam angle.
Step 7: relative radiation performance surface two dimension fitting.
Specifically, carrying out Two-dimensional Surfaces multinomial to smoothed out magnitude image A using azimuth angle alpha and downwards angle of visibility β as variable
Fitting, fitting order are even number.Precision and computation complexity are considered simultaneously, and fitting order usually takes 4.Opposite spoke after fitting
The form for penetrating performance Two-dimensional Surfaces A ' is as follows,
A '=
c00+c10α+c01β+c20α2+c11αβ+c02β2
+c30β3+c21α2β+c12αβ2+c03β3
+c40α4+c31α3β+c22α2β2+c13αβ3+c04β4
Wherein, c is multinomial coefficient.
Thus the relative radiation performance for obtaining wide angle scanning Sliding spotlight SAR satellite system, using its can to SAR image into
The high-precision relative detector calibration of row, improves picture quality.Fig. 2 is the cunning that the method for the present invention is obtained using tropical rain forest region
Dynamic Spotlight SAR Imaging satellite system relative radiation performance measurements example.
The above description is only an embodiment of the present invention, is not intended to limit the scope of the invention, all to utilize this hair
Equivalent structure or equivalent flow shift made by bright specification and accompanying drawing content, it is relevant to be applied directly or indirectly in other
Technical field is included within the scope of the present invention.
Claims (3)
1. a kind of wide angle scanning Sliding spotlight SAR satellite system relative radiation performance measurement method, which is characterized in that this method packet
Include following operating procedure:
Step 1: imaging region is chosen, after system performance tuning is completed in SAR satellite and its Ground Data Processing System, choosing
The uniform scene of radar raster-displaying is selected as imaging region；
Step 2: imaging and range attenuation correction carry out imaging to imaging region echo, and decaying of adjusting the distance carries out
Correction obtains haplopia complex pattern IX×Y, wherein X is the orientation pixel number of image, and Y is the distance of image to pixel number；
Step 3: nonisotropic scattering region is rejected, and is rejected in image and is significantly scattered Nonuniform Domain Simulation of Reservoir, to eliminate it to subsequent phase
To the adverse effect of radiance measurement；
Step 4: being smoothed image using certain rectangular window, reduces influence of noise, obtains magnitude image A；Root
It is estimated according to relative radiation fluctuation characteristic and noise level, while comprehensively considering following two factor, first is that relative radiation
The holding of energy curved surface characteristic, second is that the smooth effect of noise, the specific size for determining window；
Step 5: each pixel A of smooth amplitude image A is determined according to radar parameterxyCorresponding azimuth angle alpha and downwards angle of visibility β,
The orientation scanning range and distance that the radar parameter includes radar are to beam angle；
Step 6: using azimuth angle alpha and downwards angle of visibility β as variable, it is quasi- that Two-dimensional Surfaces multinomial is carried out to smoothed out magnitude image A
It closes, with the relative radiation performance Two-dimensional Surfaces A ' after being fitted, fitting order is even number.
2. a kind of wide angle scanning Sliding spotlight SAR satellite system relative radiation performance measurement method according to claim 1,
It is characterized in that, fitting order takes 4, and the form of the relative radiation performance Two-dimensional Surfaces A ' after fitting is as follows in step 6,
A '=
c00+c10α+c01β+c20α2+c11αβ+c02β2+c30β3+c21α2β+c12αβ2+c03β3+c40α4+c31α3β+c22α2β2+c13αβ3+
c04β4
Wherein, c is the multinomial coefficient that fitting obtains.
3. a kind of wide angle scanning Sliding spotlight SAR satellite system relative radiation performance measurement method according to claim 1,
It is characterized in that, the noise of image is relatively high if imaging region uniformity is poor, can before step 4, after step 5,
It is averaging processing using the multiple image of identical wave position, further decreases influence of noise.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115856891A (en) * | 2023-03-01 | 2023-03-28 | 中国科学院空天信息创新研究院 | High-resolution satellite-borne SAR non-uniform beam scanning imaging method |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104615836A (en) * | 2015-02-12 | 2015-05-13 | 西安电子科技大学 | Rapid prediction method for impact of spaceborne microstrip antenna array thermal deformation on electrical performance |
| CN106353777A (en) * | 2016-08-09 | 2017-01-25 | 北京空间飞行器总体设计部 | Method for analyzing radiation properties of high-resolution SAR (synthetic aperture radar) satellites |
| CN107132537A (en) * | 2017-04-28 | 2017-09-05 | 北京空间飞行器总体设计部 | A kind of SAR satellite on-orbit performance method for improving scanned based on electromechanical combination |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104615836A (en) * | 2015-02-12 | 2015-05-13 | 西安电子科技大学 | Rapid prediction method for impact of spaceborne microstrip antenna array thermal deformation on electrical performance |
| CN106353777A (en) * | 2016-08-09 | 2017-01-25 | 北京空间飞行器总体设计部 | Method for analyzing radiation properties of high-resolution SAR (synthetic aperture radar) satellites |
| CN107132537A (en) * | 2017-04-28 | 2017-09-05 | 北京空间飞行器总体设计部 | A kind of SAR satellite on-orbit performance method for improving scanned based on electromechanical combination |
Non-Patent Citations (2)
| Title |
|---|
| 王从思等: "基于单元位置误差的有源相控阵天线辐射和散射性能综合分析", 《系统工程与电子技术》 * |
| 袁玉等: "微波强度关联图像辐射性能敏感性分析", 《遥感技术与应用》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115856891A (en) * | 2023-03-01 | 2023-03-28 | 中国科学院空天信息创新研究院 | High-resolution satellite-borne SAR non-uniform beam scanning imaging method |
| CN115856891B (en) * | 2023-03-01 | 2023-05-12 | 中国科学院空天信息创新研究院 | High-resolution spaceborne SAR non-uniform beam scanning imaging method |
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