CN106646471A - On-board high resolution SAR imaging method based on azimuth spatial variation error compensation - Google Patents

On-board high resolution SAR imaging method based on azimuth spatial variation error compensation Download PDF

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CN106646471A
CN106646471A CN201611247888.4A CN201611247888A CN106646471A CN 106646471 A CN106646471 A CN 106646471A CN 201611247888 A CN201611247888 A CN 201611247888A CN 106646471 A CN106646471 A CN 106646471A
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orientation
range gate
sub
block signal
azimuth
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CN106646471B (en
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周叶剑
张磊
王冠勇
张薇
杨思全
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MINISTRY OF CIVIL AFFAIRS NATIONAL DISASTER REDUCTION CENTER
Xidian University
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MINISTRY OF CIVIL AFFAIRS NATIONAL DISASTER REDUCTION CENTER
Xidian University
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/88—Radar or analogous systems specially adapted for specific applications
    • G01S13/89—Radar or analogous systems specially adapted for specific applications for mapping or imaging
    • G01S13/90—Radar or analogous systems specially adapted for specific applications for mapping or imaging using synthetic aperture techniques, e.g. synthetic aperture radar [SAR] techniques
    • G01S13/9004—SAR image acquisition techniques
    • G01S13/9017—SAR image acquisition techniques with time domain processing of the SAR signals in azimuth

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  • Engineering & Computer Science (AREA)
  • Remote Sensing (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Physics & Mathematics (AREA)
  • Signal Processing (AREA)
  • Electromagnetism (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • General Physics & Mathematics (AREA)
  • Radar Systems Or Details Thereof (AREA)

Abstract

The invention belongs to a radar technology field, and discloses an on-board high resolution SAR imaging method based on azimuth spatial variation error compensation. The on-board high resolution SAR imaging method comprises steps that an on-board SAR radar is used to receive an echo signal, and is used for the range pulse pressure, the range migration correction, and the azimuth Fourier transform of the echo signal sequentially to acquire an azimuth wave number field signal; the azimuth partitioning of the azimuth wave number field signal is carried out in various range gates to acquire various azimuth sub-block signals after the azimuth partitioning; corresponding azimuth matched filtering functions in the various azimuth sub-blocks are calculated in a point-to-point manner, and coarse resolution imaging is carried out; coarse resolution images are calculated, and then the azimuth Fourier transform is carried out, and integration of azimuth number spectrum is realized by wave cyclic shift and splicing, and then the complete wave number spectrum of the corresponding range gate is acquired, and then azimuth inverse Fourier transform is carried out; the azimuth partitioning and the spectrum integration of the various range gates are carried out sequentially in a repeated manner until processing results corresponding to all of the range gates are acquired, and therefore a full resolution imaging result is acquired.

Description

Airborne High Resolution SAR imaging method based on orientation space-variant error compensation
Technical field
The invention belongs to Radar Technology field, more particularly to a kind of airborne high-resolution based on orientation space-variant error compensation SAR imaging methods, can be used for airborne High Resolution SAR imaging.
Background technology
Motion compensation is the important letter of airborne synthetic aperture radar (Synthetic Aperture Radar, SAR) imaging Number processing links.Under the conditions of long synthetic aperture high-resolution imaging, the accuracy of motion compensation is airborne for low latitude miniature self-service SAR imaging results are most important, and its impact will appear as distance to the space-variant with orientation.Carried SAR is moved apart from space-variant The compensation of error mainly adopts " two step penalty methods ".But the method has limitation, when airplane motion big rise and fall or radar work Make in high band, impact of the remaining orientation space-variant error to azimuth focus be can not ignore.
At present, the compensation method of orientation space-variant kinematic error mainly have sub-aperture landform and aperture Dependent Algorithm in Precision (SATA) and Accurate landform relies on motion compensation process (PTA) with aperture.SATA efficiency highs but be constant due to introducing sub-aperture kinematic error Hypothesis and affect its precision.PTA can relatively accurately compensate orientation space-variant error, but orientation wave-number spectrum process does not consider remnants Phase effect causes its precision to be still limited.
The content of the invention
The present invention provides a kind of airborne High Resolution SAR imaging method based on orientation space-variant error compensation, can accurately mend Repay high-order orientation space-variant kinematic error.
The present invention technical thought be：Using conventional RD (range Doppler) algorithm original echo is entered row distance pulse pressure and Sub-block is divided in orientation wave-number domain after RCMC (range migration correction), the accurate orientation matching of thick imaging network node-by-node algorithm is set up Filter function, carries out coarse resolution imaging.Become the thick imaging results of each sub-block of changing commanders followed by orientation Fourier and transform to orientation Wave-number domain, and cyclic shift splices obtain complete orientation wave-number spectrum successively, after being compensated finally by inverse Fourier conversion It is complete to differentiate SAR image.
To reach above-mentioned purpose, the present invention is adopted the following technical scheme that and is achieved.
A kind of airborne High Resolution SAR imaging method based on orientation space-variant error compensation, methods described comprises the steps：
Step 1, obtains the echo-signal of airborne High Resolution SAR radar, the echo-signal is entered successively row distance pulse pressure, Range migration correction, azimuth Fourier transform, obtain azimuth beam domain signal, azimuth beam domain signal be included in P away from In door；P is the positive integer more than zero；
Step 2, to the azimuth beam domain signal in p-th range gate orientation piecemeal is carried out, and is obtained in p-th range gate Q orientation sub-block signal；Wherein, the initial value of p is 1, and p=[1 ..., P], Q are the positive integer more than zero；
Step 3, to q-th orientation sub-block signal in p-th range gate, calculates q-th orientation sub-block letter The corresponding orientation matched filtering function of each data point in number, so as to obtain q-th orientation sub-block in p-th range gate All data points distinguish corresponding orientation matched filtering function in signal；Wherein, the initial value of q is 1, and q=[1 ..., Q]；
Step 4, by all data points in q-th orientation sub-block signal in p-th range gate corresponding side is distinguished Matched filtering function in position constitutes the orientation matched filter group of q-th orientation sub-block signal in p-th range gate；And will be described All data points are obtained respectively by the orientation matched filter group in q-th orientation sub-block signal in p-th range gate The filtered time-domain signal of q-th orientation sub-block signal frequency domain in p-th range gate, by q-th side in p-th range gate Coarse resolution of the time-domain signal after the block signal frequency domain filtering of seat as q-th orientation sub-block signal in p-th range gate Imaging results；And the coarse resolution imaging results to q-th orientation sub-block signal in p-th range gate carry out orientation Fu In leaf transformation, obtain the wave beam spectrum of q-th orientation sub-block signal in p-th range gate；
Step 5, the value for making q plus 1, and is repeated in execution step 3- step 4, until obtaining the Q in p-th range gate The wave beam spectrum of orientation sub-block signal, is shifted and is spelled to the wave beam spectrum of Q orientation sub-block signal in p-th range gate Connect, obtain wave beam spectrum complete in p-th range gate；
Step 6, the value for making p plus 1, and is repeated in execution step 2- step 5, complete in P range gate until obtaining Wave beam is composed, and wave beam complete in the P range gate is composed as airborne High Resolution SAR imaging results.
The characteristics of technical solution of the present invention and further it is improved to：
(1) in the step 1, obtain azimuth beam domain signal and be specially：Orientation wave-number domain signal S (Kx, x, r)：
S(Kx, x, r) and=∫ exp {-jKrc[Rn(X, x, r)+Δ rε(X, x, r)]-jKxX}dX
Wherein, x is position of orientation variable of the data point relative to beam center, and x is the azimuthal coordinates of carrier aircraft, and r is current Wave number center oblique distance variable, K under range gatexFor orientation wave number variable, KrcFor wave beam domain conversion coefficient, Krc=4 π/λ, λ are ripple It is long, Rn(X, x, r) is the target oblique distance under current distance door, For Carrier aircraft angle of squint, beam center is in the abscissa of floor projectionΔrεFor remaining orientation space-variant error.
(2) in step 2, if the azimuth beam domain signal length in p-th range gate is N, then when carrying out orientation piecemeal, side Length N of seat block signalaMeet following condition：
Wherein, PRF is pulse recurrence frequency, and M is coarse resolution Gridding length.
(3) in step 3, the corresponding orientation matched filtering function of each data point is calculated, specially：For data point (xp, R), its corresponding orientation matched filtering function phi (Kx, xp, r) it is：
Φ(Kx, xp, r)=Krc[Rn(X*, xp, r)+Δ rε(X*)]+KxX*
Wherein, x*It is point in phase bit, xpFor data point relative to beam center position of orientation, r is under current distance door For definite value.
(4) in step 4, all data points in q-th orientation sub-block signal in p-th range gate are passed through respectively The orientation matched filter group, obtains the filtered time domain letter of q-th orientation sub-block signal frequency domain in p-th range gate Number, specially：
For the data point (x in q-th orientation sub-block signal in p-th range gatep, r), it is by the orientation With the time-domain signal S after the frequency domain filtering obtained after wave filter groupu(x, r) is：
Wherein, Kx∈[-ΔKa/ 2, Δ Ka/ 2] it is orientation wave number variable, Δ KaFor orientation wave number spectral width, KuFor orientation ripple Shuo Pu centers.
(5) in step 5, the wave beam spectrum of Q orientation sub-block signal in p-th range gate is shifted and is spelled Connect, obtain wave beam spectrum complete in p-th range gate, specifically include：
After obtaining the wave beam spectrum of Q orientation sub-block signal in p-th range gate, the ripple of the Q orientation sub-block signal Beam is composed respectively about origin symmetry；
Its wave-number spectrum is displaced to according to location order to each the wave beam spectrum in the wave beam spectrum of the Q orientation sub-block signal Center and causes each side relative to the position of whole spectrum widths after splicing to the wave beam of Q orientation sub-block signal spectrum The wave beam of seat block signal composes continuous and non-overlapping copies.
The present invention is had the advantage that compared with prior art：
(1) present invention processes thought using rear orientation projection, compared with traditional orientation space-variant movement compensating algorithm, it is possible to achieve Vernier focusing under the conditions of the big kinematic error of high band；(2) present invention processes thought using piecemeal, calculates with traditional rear orientation projection Method is compared and effectively reduce operand.
Description of the drawings
In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing The accompanying drawing to be used needed for having technology description is briefly described, it should be apparent that, drawings in the following description are only this Some embodiments of invention, for those of ordinary skill in the art, on the premise of not paying creative work, can be with Other accompanying drawings are obtained according to these accompanying drawings.
Fig. 1 is a kind of airborne High Resolution SAR imaging side based on orientation space-variant error compensation provided in an embodiment of the present invention The schematic flow sheet of method；
Fig. 2 is wave-number spectrum displacement, the splicing schematic diagram that emulation provided in an embodiment of the present invention is adopted；
Fig. 3 is point target kinematic error schematic diagram in emulation one provided in an embodiment of the present invention；
Fig. 4 is FFBP algorithms and all kinds of algorithm orientation pulse respond pair in emulation one provided in an embodiment of the present invention Compare schematic diagram；
Fig. 5 is that FFBP processes measured data result schematic diagram in emulation two provided in an embodiment of the present invention；
Fig. 6 is that FFBP shows with all kinds of algorithm process partial enlargement Comparative results in emulation two provided in an embodiment of the present invention It is intended to；
Fig. 7 is in emulation two provided in an embodiment of the present invention, with reference to scattering point orientation pulse respond contrast schematic diagram.
Specific embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete Site preparation is described, it is clear that described embodiment is only a part of embodiment of the invention, rather than the embodiment of whole.It is based on Embodiment in the present invention, it is every other that those of ordinary skill in the art are obtained under the premise of creative work is not made Embodiment, belongs to the scope of protection of the invention.
The embodiment of the present invention provides a kind of airborne High Resolution SAR imaging method based on orientation space-variant error compensation, such as Fig. 1 Shown, methods described comprises the steps：
Step 1, obtains the echo-signal of airborne High Resolution SAR radar, the echo-signal is entered successively row distance pulse pressure, Range migration correction, azimuth Fourier transform, obtain azimuth beam domain signal, azimuth beam domain signal be included in P away from In door；P is the positive integer more than zero.
In the step 1, obtain azimuth beam domain signal and be specially：Orientation wave-number domain signal S (Kx, x, r)：S(Kx, x, r) =∫ exp {-jKrc[Rn(X, x, r)+Δ rε(X, x, r)]-jKxX}dX
Wherein, x is position of orientation variable of the data point relative to beam center, and x is the azimuthal coordinates of carrier aircraft, and r is current Wave number center oblique distance variable, K under range gatexFor orientation wave number variable, KrcFor wave beam domain conversion coefficient, Krc=4 π/λ, λ are ripple It is long, Rn(X, x, r) is the target oblique distance under current distance door, For Carrier aircraft angle of squint, beam center is in the abscissa of floor projectionΔrεFor remaining orientation space-variant error.
Step 2, to the azimuth beam domain signal in p-th range gate orientation piecemeal is carried out, and is obtained in p-th range gate Q orientation sub-block signal；Wherein, the initial value of p is 1, and p=[1 ..., P], Q are the positive integer more than zero.
In step 2, if the azimuth beam domain signal length in p-th range gate is N, then when carrying out orientation piecemeal, orientation Length N of sub-block signalaMeet following condition：
Wherein, PRF is pulse recurrence frequency, and M is coarse resolution Gridding length.
Then above-mentioned foundation makes the frequency spectrum that orientation sub-block is included be not more than the frequency spectrum of coarse resolution grid, that is to say, that orientation The frequency spectrum of block can not occur aliasing in coarse resolution grid.
Step 3, to q-th orientation sub-block signal in p-th range gate, calculates q-th orientation sub-block letter The corresponding orientation matched filtering function of each data point in number, so as to obtain q-th orientation sub-block in p-th range gate All data points distinguish corresponding orientation matched filtering function in signal；Wherein, the initial value of q is 1, and q=[1 ..., Q].
In step 3, the corresponding orientation matched filtering function of each data point is calculated, specially：For data point (xp, rp), Its corresponding orientation matched filtering function phi (Kx, xp, rp) be：
Φ(Kx, xp, rp)=Krc[Rn(X*, xp, rp)+Δrε(X*)]+KxX*
Wherein, x*It is point in phase bit, xpFor data point relative to beam center position of orientation, r is under current distance door For definite value.
Specifically, x*It is point in phase bit：
X*=p1y+p2y2+p3y3+x
Wherein, a0-a4It is by RnThe coefficient of polynomial fitting that Taylor launches near X-x=0, has：
Δrε(X)≈a0+a1(X-x)+a2(X-x)2+a3(X-x)3+a4(X-x)4
Step 4, by all data points in q-th orientation sub-block signal in p-th range gate corresponding side is distinguished Matched filtering function in position constitutes the orientation matched filter group of q-th orientation sub-block signal in p-th range gate；And will be described All data points are obtained respectively by the orientation matched filter group in q-th orientation sub-block signal in p-th range gate The filtered time-domain signal of q-th orientation sub-block signal frequency domain in p-th range gate, by q-th side in p-th range gate Coarse resolution of the time-domain signal after the block signal frequency domain filtering of seat as q-th orientation sub-block signal in p-th range gate Imaging results；And the coarse resolution imaging results to q-th orientation sub-block signal in p-th range gate carry out orientation Fu In leaf transformation, obtain the wave beam spectrum of q-th orientation sub-block signal in p-th range gate.
In step 4, all data points in q-th orientation sub-block signal in p-th range gate are passed through respectively institute Orientation matched filter group is stated, the filtered time-domain signal of q-th orientation sub-block signal frequency domain in p-th range gate is obtained, Specially：
For the data point (x in q-th orientation sub-block signal in p-th range gatep, r), it is by the orientation With the time-domain signal S after the frequency domain filtering obtained after wave filter groupu(x, r) is：
Wherein, Kx∈[-ΔKa/ 2, Δ Ka/ 2] it is orientation wave number variable, Δ KaFor orientation wave number spectral width, KuFor orientation ripple Shuo Pu centers.
Step 5, the value for making q plus 1, and is repeated in execution step 3- step 4, until obtaining the Q in p-th range gate The wave beam spectrum of orientation sub-block signal, is shifted and is spelled to the wave beam spectrum of Q orientation sub-block signal in p-th range gate Connect, obtain wave beam spectrum complete in p-th range gate.
In step 5, the wave beam spectrum of Q orientation sub-block signal in p-th range gate is shifted and spliced, obtained Complete wave beam spectrum in p-th range gate, as shown in Fig. 2 specifically including：
After obtaining the wave beam spectrum of Q orientation sub-block signal in p-th range gate, the ripple of the Q orientation sub-block signal Beam is composed respectively about origin symmetry；
Its wave-number spectrum is displaced to according to location order to each the wave beam spectrum in the wave beam spectrum of the Q orientation sub-block signal Center and causes each side relative to the position of whole spectrum widths after splicing to the wave beam of Q orientation sub-block signal spectrum The wave beam of seat block signal composes continuous and non-overlapping copies.
Step 6, the value for making p plus 1, and is repeated in execution step 2- step 5, complete in P range gate until obtaining Wave beam is composed, and wave beam complete in the P range gate is composed as airborne High Resolution SAR imaging results.
The effect of the present invention can be described further by following emulation experiment：
1) simulated conditions：
Point target simulation parameter of the present invention is as shown in table 1：
The point target simulation parameter of table 1
Wherein kinematic parameter is calculated according to actual measurement aircraft inertial navigation record and obtained, as shown in Figure 3.
2. emulation content and interpretation of result：
Emulation 1：With the inventive method under 0 degree, 5 degree of angles of squint, one-dimensional image and and TWO- are carried out to wave number central point STEP, PTA, SATA algorithm process result is contrasted, as shown in figure 4, using peak sidelobe ratio (Peak Side-Lobe respectively Ratio, PSLR), integration secondary lobe ratio (Integrated Side-Lobe Ratio, PSLR) and response pulse duration (Impulse Response Width, IRW) quantify to compare result as shown in table 2, table 3 as evaluation criterion.
Table 2 emulates quantitative analysis result under one 0 degree of angles of squint
Table 3 emulates quantitative analysis result under one 5 degree of angles of squint
Emulation 2：It is imaged under positive side-looking band pattern with the inventive method, and is tied with Two-step, PTA, SATA algorithm Fruit is contrasted.With emulation one, size of data is 8192*16384 to simulation parameter, intercepts part result as shown in Figure 5.Choosing Take figure Scene 1, scene 2 carries out contrasting as shown in Figure 6 with other algorithm process results.Two scattering points A, B in figure are chosen, it is right Than its orientation impulse response function as shown in fig. 7, its quantitative statisticses result is as shown in table 4,5.
Table 4 emulates two scattering point A quantitative analysis results
Table 5 emulates two scattering point B quantitative analysis results
3. analysis of simulation result：
PLSR, ISLR, IRW value that can be seen that the method that the present invention is provided from table 2, table 3 is respectively less than remaining each algorithm, Therefore effect is best.
It can be found that " Two-Step " motion compensation process effect is worst from Fig. 6, the result of PTA and SATA is deposited In different degrees of blooming effect, this is because there is remaining uncompensated kinematic error in block margin point, and what the present invention was provided Preferably, the result for isolated point A, B also demonstrates the performance of the method for present invention offer to method effect.
The above, the only specific embodiment of the present invention, but protection scope of the present invention is not limited thereto, any Those familiar with the art the invention discloses technical scope in, change or replacement can be readily occurred in, all should contain Cover within protection scope of the present invention.Therefore, protection scope of the present invention should be defined by the scope of the claims.

Claims (6)

1. a kind of airborne High Resolution SAR imaging method based on orientation space-variant error compensation, it is characterised in that methods described includes Following steps：
Step 1, obtains the echo-signal of airborne High Resolution SAR radar, and to the echo-signal row distance pulse pressure, distance are entered successively Migration correction, azimuth Fourier transform, obtain azimuth beam domain signal, and azimuth beam domain signal is included in P range gate It is interior；P is the positive integer more than zero；
Step 2, to the azimuth beam domain signal in p-th range gate orientation piecemeal is carried out, and obtains Q in p-th range gate Orientation sub-block signal；Wherein, the initial value of p is 1, and p=[1 ..., P], Q are the positive integer more than zero；
Step 3, to q-th orientation sub-block signal in p-th range gate, calculates in q-th orientation sub-block signal The corresponding orientation matched filtering function of each data point, so as to obtain q-th orientation sub-block signal in p-th range gate Interior all data points distinguish corresponding orientation matched filtering function；Wherein, the initial value of q is 1, and q=[1 ..., Q]；
Step 4, by all data points in q-th orientation sub-block signal in p-th range gate corresponding orientation is distinguished The orientation matched filter group of q-th orientation sub-block signal in p-th range gate is constituted with filter function；And by the pth All data points obtain pth respectively by the orientation matched filter group in q-th orientation sub-block signal in individual range gate The filtered time-domain signal of q-th orientation sub-block signal frequency domain in individual range gate, by q-th orientation in p-th range gate The filtered time-domain signal of sub-block signal frequency domain as q-th orientation sub-block signal in p-th range gate coarse resolution into As result；And the coarse resolution imaging results to q-th orientation sub-block signal in p-th range gate are carried out in orientation Fu Leaf transformation, obtains the wave beam spectrum of q-th orientation sub-block signal in p-th range gate；
Step 5, the value for making q plus 1, and is repeated in execution step 3 to step 4, until obtaining Q in p-th range gate side The wave beam spectrum of seat block signal, is shifted and is spelled to the wave beam spectrum of Q orientation sub-block signal in p-th range gate Connect, obtain wave beam spectrum complete in p-th range gate；
Step 6, the value for making p plus 1, and is repeated in execution step 2 to step 5, until obtaining wave beam complete in P range gate Spectrum, and wave beam complete in the P range gate is composed as airborne High Resolution SAR imaging results.
2. a kind of airborne High Resolution SAR imaging method based on orientation space-variant error compensation according to claim 1, it is special Levy and be, in the step 1, obtain azimuth beam domain signal and be specially：Orientation wave-number domain signal S (Kx,x,r)：
S(Kx, x, r) and=∫ exp {-jKrc[Rn(X,x,r)+△rε(X,x,r)]-jKxX}dX
Wherein, x is position of orientation variable of the data point relative to beam center, and X is the azimuthal coordinates of carrier aircraft, and r is p-th distance The lower wave number center oblique distance variable of door, KxFor orientation wave number variable, KrcFor wave beam domain conversion coefficient, Krc=4 π/λ, λ are wavelength, Rn (X, x, r) is the target oblique distance under p-th range gate, For carrier aircraft Angle of squint, beam center is in the abscissa of floor projection△rεFor remaining orientation space-variant error.
3. a kind of airborne High Resolution SAR imaging method based on orientation space-variant error compensation according to claim 1, it is special Levy and be, in step 2, if the azimuth beam domain signal length in p-th range gate is N, then to the orientation in p-th range gate When Beam Domain signal carries out orientation piecemeal, length N of each the orientation sub-block signal for obtainingaMeet following condition：
N a N · P R F ≤ M N · P R F
Wherein, PRF is pulse recurrence frequency, and M is coarse resolution Gridding length.
4. a kind of airborne High Resolution SAR imaging method based on orientation space-variant error compensation according to claim 2, it is special Levy and be, in step 3, calculate the corresponding orientation matched filtering function of each data point, specially：For in p-th range gate Q-th orientation sub-block signal in data point (xp, r), its corresponding orientation matched filtering function phi (Kx,xp, r) it is：
Φ(Kx,xp, r)=Krc[Rn(X*,xp,rp)+△rε(X*)]+KxX*
Wherein, X*It is point in phase bit, xpFor data point relative to beam center position of orientation, r be p-th range gate under ripple Number center oblique distance variable, r is definite value under p-th range gate.
5. a kind of airborne High Resolution SAR imaging method based on orientation space-variant error compensation according to claim 4, it is special Levy and be, in step 4, by all data points in q-th orientation sub-block signal in p-th range gate respectively by described Orientation matched filter group, obtains the filtered time-domain signal of q-th orientation sub-block signal frequency domain in p-th range gate, tool Body is：
For the data point (x in q-th orientation sub-block signal in p-th range gatep, r), it is filtered by orientation matching Time-domain signal S after the frequency domain filtering obtained after ripple device groupu(x, r) is：
S u ( x , r ) = ∫ K u - ΔK a / 2 K u + ΔK a / 2 exp [ jK x ( x - x p ) ] dK x
Wherein, KxFor orientation wave number variable, Kx∈[-△Ka/2,△Ka/ 2], △ KaFor orientation wave number spectral width, KuFor orientation ripple Shuo Pu centers, ∈ is represented and belonged to.
6. a kind of airborne High Resolution SAR imaging method based on orientation space-variant error compensation according to claim 5, it is special Levy and be, in step 5, the wave beam spectrum of Q orientation sub-block signal in p-th range gate is shifted and spliced, obtain Complete wave beam spectrum in p-th range gate, specifically includes：
After obtaining the wave beam spectrum of Q orientation sub-block signal in p-th range gate, the wave beam of the Q orientation sub-block signal is composed Respectively about origin symmetry；
Its wave-number spectrum center is displaced to according to location order to each the wave beam spectrum in the wave beam spectrum of the Q orientation sub-block signal Relative to the position of whole spectrum widths, and each orientation is caused after splicing to the wave beam of Q orientation sub-block signal spectrum The wave beam of block signal composes continuous and non-overlapping copies.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108459321A (en) * 2018-02-07 2018-08-28 杭州电子科技大学 Justify the big strabismus High Resolution SAR Imaging method of model based on range-azimuth
CN110646765A (en) * 2019-09-26 2020-01-03 杨强 Riemann distance-based generalized sidelobe cancellation algorithm
CN111551935A (en) * 2020-05-26 2020-08-18 北京无线电测量研究所 Motion error compensation method for synthetic aperture radar

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5627543A (en) * 1994-08-05 1997-05-06 Deutsche Forschungsanstalt Fur Luft-Und Raumfahrt E.V. Method of image generation by means of two-dimensional data processing in connection with a radar with synthetic aperture
CN104391297A (en) * 2014-11-17 2015-03-04 南京航空航天大学 Sub-aperture partition PFA (Polar Format Algorithm) radar imaging method
CN105487074A (en) * 2015-11-26 2016-04-13 电子科技大学 Bistatic synthetic aperture radar numerical range Doppler imaging method
CN105974414A (en) * 2016-06-24 2016-09-28 西安电子科技大学 High resolution spotlight SAR self-focusing imaging method based on two-dimensional self-focusing
CN105974415A (en) * 2016-06-24 2016-09-28 西安电子科技大学 High precision compensation method for airborne SAR orientation space-variant motion error
JP6011746B1 (en) * 2015-12-03 2016-10-19 三菱電機株式会社 Synthetic aperture radar apparatus and signal processing apparatus
CN106199599A (en) * 2016-06-24 2016-12-07 西安电子科技大学 A kind of precise motion compensation method of airborne high-resolution SAR

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5627543A (en) * 1994-08-05 1997-05-06 Deutsche Forschungsanstalt Fur Luft-Und Raumfahrt E.V. Method of image generation by means of two-dimensional data processing in connection with a radar with synthetic aperture
CN104391297A (en) * 2014-11-17 2015-03-04 南京航空航天大学 Sub-aperture partition PFA (Polar Format Algorithm) radar imaging method
CN105487074A (en) * 2015-11-26 2016-04-13 电子科技大学 Bistatic synthetic aperture radar numerical range Doppler imaging method
JP6011746B1 (en) * 2015-12-03 2016-10-19 三菱電機株式会社 Synthetic aperture radar apparatus and signal processing apparatus
CN105974414A (en) * 2016-06-24 2016-09-28 西安电子科技大学 High resolution spotlight SAR self-focusing imaging method based on two-dimensional self-focusing
CN105974415A (en) * 2016-06-24 2016-09-28 西安电子科技大学 High precision compensation method for airborne SAR orientation space-variant motion error
CN106199599A (en) * 2016-06-24 2016-12-07 西安电子科技大学 A kind of precise motion compensation method of airborne high-resolution SAR

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
杨磊等: "基于方位波数域聚束模式PFA的运动补偿新方法研究", 《电子与信息学报》 *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108459321A (en) * 2018-02-07 2018-08-28 杭州电子科技大学 Justify the big strabismus High Resolution SAR Imaging method of model based on range-azimuth
CN110646765A (en) * 2019-09-26 2020-01-03 杨强 Riemann distance-based generalized sidelobe cancellation algorithm
CN111551935A (en) * 2020-05-26 2020-08-18 北京无线电测量研究所 Motion error compensation method for synthetic aperture radar
CN111551935B (en) * 2020-05-26 2022-03-04 北京无线电测量研究所 Motion error compensation method for synthetic aperture radar

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