CN101561503A - Method for quickly imaging for double-linear-array three-dimensional imaging synthetic aperture radar - Google Patents
Method for quickly imaging for double-linear-array three-dimensional imaging synthetic aperture radar Download PDFInfo
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Abstract
The invention provides a method for quickly imaging for a double-linear-array three-dimensional imaging synthetic aperture radar on the basis of self-adaption, which aims at the characteristic that an echo wave of an actual double-linear-array three-dimensional imaging synthetic aperture radar only comprises an echo wave signal of a specific curved surface in a three-dimensional space. A self-adaptive curved surface prediction technique is adopted to carry out curved surface prediction and imaging processing aiming at the specific curved surface in the three-dimensional space so as to better solve the problem of large computation workload of the prior imaging method of the double-linear-array three-dimensional imaging synthetic aperture radar. The method can be applied to the fields of the synthetic aperture radar imaging, the earth remote sensing, the geology surveying and drawing, and the like.
Description
Technical field
The present technique invention belongs to the Radar Technology field, and it has been particularly related to the synthetic aperture radar (SAR) technical field of imaging.
Background technology
Three-dimensional imaging is the key character that three-dimensional imaging synthetic aperture radar (SAR) is different from other remotely sensed image systems, because wide, round-the-clock, the round-the-clock of its mapping coverage has broad application prospects at aspects such as topographic mapping, environment measuring, hazard forecastings.
Current technology relevant for D S AR mainly comprises interference SAR (InSAR) technology, curve S AR technology (CSAR) and linear array SAR (LASAR) technology.Interference technique is a kind of SAR imaging technique that does not possess third dimension resolution characteristic, and it just can not provide accurate three-dimensional reconstruction ability theoretically.Curve S AR must set the flight path of motion platform in three dimensions, but the TRAJECTORY CONTROL precision of antenna phase center is low, and this is a constraint to D S AR system.For present research focus list linear-array SAR, because it exists as document Tsz-King Chan, Yasuo Kuga, the image blur problem of being mentioned in " Experimental studies on circular SARimaging in clutter using angular correlation function technique " that exists during less than resolution apart from history when difference, this system also is subjected to the restriction of imaging landform to a certain extent.
Existing bistatic linear-array three-dimensional imaging synthetic aperture radar (BLASAR) is that transmitter is fixed on the flat pad, linear array antenna is fixed on the receiving platform, receive planar array with synthetic, and a kind of novel polarization sensitive synthetic aperture radar system that carries out three-dimensional imaging.The double-linear-array synthetic-aperture radar is in the dimensional topography imaging that realizes over the ground, it has overcome the shortcoming and the constraint of existing three-dimensional imaging SAR system, inherited all advantages of two stations synthetic-aperture radar simultaneously, for example: scattered information anti-stealthy, target is abundant, radar cross section amasss increases or the like.The document of understanding and having delivered according to the inventor, for example: J.Klare, A.Brenner, J.Ender, " A New Airborne Radar for 3D Imaging-Image Fromation using theARTINO Principle-" EURAD, Dresden, Germany, 2006.B.D.Rigling and R.L.Moses, " Flight path strategies for 3-D scene reconstruction frombistatic SAR " IEE proceedings Radar Sonar Navig., vol.151 No 3.pp.149-157, June.2004. the bistatic linear-array three-dimensional imaging synthetic aperture radar imaging method can be divided into three classes: time domain three-D imaging method, frequency domain three-D imaging method and dimensionality reduction image processing method.Time domain approach is received the antenna element distance by calculating each scattering point to sending out, and carries out coherence stack and realize the bistatic linear-array three-dimensional imaging synthetic aperture Radar Imaging Processing; Frequency domain method is handled coherent accumulation and is transformed to the multiplication of frequency domain and the operation of projection, realizes the bistatic linear-array three-dimensional imaging synthetic aperture Radar Imaging Processing; The dimensionality reduction image processing method is decomposed into several one-dimensional correlations with the higher-dimension relevant issues and handles problems, and handles operand to reduce.
Said method all is to regard bistatic linear-array three-dimensional imaging synthetic aperture radar imagery problem as three-dimensional matched filtering problem in essence.During this spatial matched filtering whole imaging space is carried out the imaging of full spatial domain, its operand is very huge, understands according to the inventor, and current also do not have again the people to propose the less three-D imaging method of a kind of operand.
Summary of the invention
The objective of the invention is in order to overcome the big problem of operand of existing three-dimensional imaging synthetic aperture radar formation method, a kind of double-linear-array three-dimensional synthetic aperture radar fast imaging method is provided, this method is converted into the two-dimensional imaging problem to the three-dimensional imaging problem of three-dimensional synthetic aperture radar, greatly reduce the operand of bistatic linear-array three-dimensional imaging synthetic aperture radar, realized three dimensions imaging large scene.
Content of the present invention for convenience of description, at first make following term definition:
Bistatic linear-array three-dimensional imaging synthetic aperture radar (BLASAR) is that transmitter is fixed on the flat pad, and the linear array receiver is fixed on the receiving platform, with synthetic two-dimensional planar array, and a kind of novel polarization sensitive synthetic aperture radar system that carries out three-dimensional imaging.
Synthetic-aperture radar gauged distance compression method is meant and utilizes the synthetic-aperture radar parameter that transmits, and adopts following formula to generate reference signal, and the process that adopts matched filtering technique the distance of synthetic-aperture radar to be carried out filtering to signal.
Wherein, f (t) is a reference function, and B is the signal bandwidth of radar emission baseband signal, T
PBe the radar emission signal pulse width, t is an independent variable, span from
Arrive
See document " radar imagery technology " for details, protect polished grade and write, the Electronic Industry Press publishes.
Bistatic linear-array three-dimensional imaging synthetic aperture radar image space is meant the scene areas that the synthetic-aperture radar wave beam shines.
Definition 4, bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method
Bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method is the expansion of conventional synthetic-aperture radar two dimension back projection formation method.It is historical to the distance of two each array element phase center of take-up array antenna of standing that this method is at first calculated scattering point, selects the data of respective distance and unit, and the doppler phase of the column criterion of going forward side by side compensates and coherent accumulation, obtains the scattering coefficient of this point.This method flow diagram is seen patent accompanying drawing.See document " radar imagery technology " for details, protect polished grade and write, the Electronic Industry Press publishes.
The Threshold detection technology is meant under the backscattering coefficient of target distributes known situation, according to false-alarm probability or the detection probability set the backscattering coefficient of target is monitored, when backscattering coefficient was higher than detection threshold, target existed, otherwise target does not exist.See document " input and estimation " for details, Xiang Jingcheng etc. write, publishing house of University of Electronic Science and Technology.
By the data ordering order, ascending, one by one data are carried out certain operation, till all data are all executed this operation.See document " auto adapted filtering " for details, Gong Yaohuan writes, and the Electronic Industry Press publishes.
Definition 7, bistatic linear-array three-dimensional imaging synthetic aperture radar theoretical resolution
Bistatic linear-array three-dimensional imaging synthetic aperture radar theoretical resolution is meant according to the bistatic linear-array three-dimensional imaging synthetic aperture radar system parameter, comprise transmitted signal bandwidth, the ultimate resolution that the linear-array three-dimensional imaging synthetic aperture radars of length of synthetic aperture and the decision of linear array antenna length can reach.See document " two stations synthetic aperture radar image-forming principle " for details, Tang Ziyue etc. write, and Science Press publishes.
Definition 8, bistatic linear-array three-dimensional imaging synthetic aperture racon collection
Bistatic linear-array three-dimensional imaging synthetic aperture radar imagery result is the curved surface in the three dimensions, can use following function representation:
z＝h(i，j)
Wherein, (i j) is index set, h (i, j) expression (i, j) Dui Ying height.
Definition 9, the synthetic-aperture radar backscattering coefficient regularity of distribution
The synthetic-aperture radar backscattering coefficient regularity of distribution is meant the regularity of distribution that transmitting of synthetic-aperture radar turns back to the wave source direction after the scatterer scattering scattared energy is obeyed.See document " radar handbook " the 11st, 12 chapters for details, Merrill I.Skolnik chief editor, Wang Jun etc. translate, and the Electronic Industry Press publishes
The invention provides a kind ofly based on adaptive quickly imaging for double-linear-array three-dimensional imaging synthetic aperture radar method, it may further comprise the steps:
Initialized imaging system parameter comprises: flat pad and receiving platform velocity
Platform initial position vector
The electromagnetic wave number of radar emission, note is K
c, the relative platform of each array element of receiver linear array antenna center, note is P
Ri, wherein i is each array element sequence number of antenna, is natural number, i=0, and 1 ..., M, M are each array element sum of receiver linear array antenna, the signal bandwidth of radar emission baseband signal, and note is B, the radar emission signal pulse width, note is T
p, radar receives the ripple door and continues width, and note is T
d, the sample frequency of radar receiving system, note is f
s, the pulse repetition rate of radar system, note is PRF, and receiving system reception ripple door is remembered and is T with respect to the delay of the transmitted wave door that transmits
DAbove-mentioned parameter is the canonical parameter of bistatic linear-array three-dimensional imaging synthetic aperture radar system, wherein, and the electromagnetic wave number K of radar emission
c, the signal bandwidth B of radar emission baseband signal, radar emission signal pulse width T
p, radar receives the ripple door and continues width T
d, the sample frequency f of radar receiving system
s, the pulse repetition rate PRF of radar system and receiving system receive the ripple door and determine in bistatic linear-array three-dimensional imaging synthetic aperture Radar Design process with respect to the delay of the transmitted wave door that transmits; Wherein, send out, receive the platform speed vector
And initial position vector
In bistatic linear-array three-dimensional imaging synthetic aperture radar observation conceptual design, determine;
Adopt synthetic-aperture radar gauged distance compression method to the synthetic aperture distance by radar to echo data D
eCompress, obtain the bistatic linear-array three-dimensional imaging synthetic aperture radar data after distance is compressed, note is E
c
Adopting bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, is the regional Ω of 7 * 7 * H (H is the reference altitude of imaging scene) to zone in the bistatic linear-array three-dimensional imaging synthetic aperture radar image space
0={ (x
i, y
j, h) | i=0 ... 6, j=0 ... 6, h ∈ [H/2, H/2] } in institute carry out imaging a little and handle, obtain that the zone is Ω in the bistatic linear-array three-dimensional imaging synthetic aperture radar image space
0The interior backscattering coefficient of being had a few also is that bistatic linear-array three-dimensional imaging synthetic aperture racon collection is
In institute have a few the edge highly to the distribution function of backscattering coefficient, note is done: σ (x, y, h);
To index set
Pairing backscattering coefficient distribution function along height to adopt the traversal method to search for to obtain distribution function along height to the scattering coefficient maximal value and the height at corresponding maximal value place with it; Wherein, two stations synthetic-aperture radar along the height to backscattering coefficient distribution function σ (x, y, h) maximal value σ
Max(x, y) expression, and corresponding highly with h (x, y) expression;
Step 4, along x to highly carrying out match prediction;
Altitude information h (the x that the polynomial fitting method of employing standard is capable to known y=0
i, 0), i=0 ... 6 carry out fitting of a polynomial, and our exponent number of selecting match is 3 herein, promptly carries out three rank surface fitting and predictions, obtains fitting function h=f (x), and x=7 is brought into fitting function h=f (x), obtains pre-computed altitude h
p(7,0);
According to the regularity of distribution of the backscattering coefficient of synthetic-aperture radar, choose Rayleigh---Bezier distributes; Set false-alarm probability α or detection probability δ, go out detection threshold θ according to false-alarm probability distribution function or detection probability distribution function and Threshold detection technique computes; Here the distribution function of our known detection probability is a Rayleigh---Bessel's function, obtain detection threshold by average and the variance of calculating this function;
The backscattering coefficient maximal value σ that obtains according to step 3
Max(x y), chooses the capable σ of y=0
Max(x
i, 0), i=0 ... 6, calculate the intermediate value and the variances sigma of this class value respectively
Med, s
σ, utilize formula
Obtain the average amplitude ss, according to the three dB bandwidth detection criteria,
Be probability average, the s of distribution function
σBe its variance;
Setting detection probability is 0.8, utilizes the Threshold detection technology, and we obtain detection threshold θ;
The true altitude of step 6, search bistatic linear-array three-dimensional imaging synthetic aperture radar map picture point;
Adopt bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, to the point in the three-dimensional imaging space (7,0, h
p) carry out imaging, obtain point (7,0, h
p) backscattering coefficient σ (7,0, h
p);
When σ (7,0, h
p)＜θ carries out upstream operation, and upstream operation is defined as and adopts bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, at point (x, y is h) under the situation of imaging, to being arranged in the point (x of imaging space, y, h+k Δ h), imaging is carried out in k 〉=1; Therefore earlier to the point in the three-dimensional imaging space (7,0, h
p+ Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p+ Δ h), wherein Δ h be the bistatic linear-array three-dimensional imaging synthetic aperture radar along height to resolution; Judgement σ (7,0, h
p+ Δ h) whether greater than thresholding θ, if σ (7,0, h
p+ Δ h)＞θ, adopt bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, to the point in the three-dimensional imaging space (7,0, h
p+ 2 Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p+ 2 Δ h), when σ (7,0, h
p+ 2 Δ h)＜and σ (7,0, h
p+ Δ h), jumps out this search, and get σ
Max(7,0)=σ (7,0, h
p+ Δ h), h (7,0)=h+ Δ h, when σ (7,0, h
p+ 2 Δ h)＞and σ (7,0, h
p+ Δ h), to point (7,0, h
p+ 3 Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p+ 3 Δ h), when σ (7,0, h
p+ 3 Δ h)＜and σ (7,0, h
p+ 2 Δ h), jump out this search, and get σ
Max(7,0)=σ (7,0, h
p+ 2 Δ h), h (7,0)=h+2 Δ h, when σ (7,0, h
p+ 2 Δ h)＜and σ (7,0, h
p+ Δ h), continue this upstream operation, until be met condition σ (7,0, h
p+ (k-1) Δ h)＜and σ (7,0, h
p+ k Δ h)＞and σ (7,0, h
p+ (k+1) Δ h) k value, this seasonal σ
Max(7,0)=σ (7,0, h
p+ k Δ h), h (7,0)=h+k Δ h; When σ (7,0, h
p+ Δ h)＜and θ, carry out downstream operation, downstream operation is defined as and adopts bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, at point (x, y is h) under the situation of imaging, to being arranged in the point (x of imaging space, y, h+k Δ h), imaging is carried out in k≤-1; Therefore to point (7,0, h
p-Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p-Δ h), if σ (7,0, h
p-Δ h)＞θ, to point (7,0, h
p-2 Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p-2 Δ h), if σ (7,0, h
p-2 Δ h)＜and σ (7,0, h
p-Δ h), jumps out this search, and make σ
Max(7,0)=σ (7,0, h
p-Δ h), h (7,0)=h-Δ h, when σ (7,0, h
p-2 Δ h)＞and σ (7,0, h
p-Δ h), to point (7,0, h
p-3 Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p-3 Δ h), when σ (7,0, h
p-3 Δ h)＜and σ (7,0, h
p-2 Δ h), jump out this search, and get σ
Max(7,0)=σ (7,0, h
p-2 Δ h), h (7,0)=h-2 Δ h, when σ (7,0, h
p-3 Δ h)＞and σ (7,0, h
p-2 Δ h) continue this downstream operation, until be met condition σ (7,0, h
p-(k-1) Δ h)＜and σ (7,0, h
p-k Δ h)＞and σ (7,0, h
p-(k+1) Δ h) k value, this seasonal σ
Max(7,0)=σ (7,0, h
p-k Δ h), h (7,0)=h-k Δ h; K=2 wherein ... Δ hH/2; When σ (7,0, h
p-Δ h)＜θ, change the upstream operation at k=2 place over to, when σ (7,0, h
p+ 2 Δ h)＜and θ, change the downstream operation at k=2 place over to, alternatively up and down search like this is until searching backscattering coefficient and the corresponding height value that satisfies condition; When not searching the backscattering coefficient that satisfies condition, get the final height of the height value of backscattering coefficient maximum as imaging;
When σ (7,0, h
p)＞θ adopts bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, to point (7,0, h
p+ Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p+ Δ h), to the point in the three-dimensional imaging space (7,0, h
p-Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p-Δ h), Δ h meaning is the same; When σ (7,0, h
p-Δ h)＜and σ (7,0, h
p)＞σ (7,0, h
p+ Δ h), jumps out this search, and get σ
Max(7,0)=σ (7,0, h
p), h (7,0)=h; When σ (7,0, h
p-Δ h)＜and σ (7,0, h
p)＜σ (7,0, h
p+ Δ h), enters the upstream operation of narrating above, until backscattering coefficient that obtains to satisfy condition and corresponding height value; When σ (7,0, h
p-Δ h)＞and σ (7,0, h
p)＞σ (7,0, h
p+ Δ h), enters the downstream operation of narrating above, until backscattering coefficient that obtains to satisfy condition and corresponding height value; When σ (7,0, h
p-Δ h)＞and σ (7,0, h
p)＜σ (7,0, h
p+ Δ h), enters full-height search, and get maximum scattering coefficient and corresponding height thereof as scattering coefficient that satisfies condition and height; When carrying out upstream operation or downstream operation, not jumping out search, then get scattering coefficient and height that maximum scattering coefficient and corresponding height conduct thereof satisfy condition equally;
After the above-mentioned operation steps of process, we obtain the maximum backscattering coefficient σ with curve fitting and Forecasting Methodology
Max(7,0) and corresponding height h (7,0);
Step 7, based on the full line prediction of sliding window;
The window length of getting height value is 7, promptly obtains one group of new height value h (x along x to slip
i, 0), i=1 ... 7, repeat the Forecasting Methodology of using step 5 identical with step 6, be met the maximum backscattering coefficient σ of condition
Max(8,0) and corresponding height h (8,0) slide window position so successively, obtain all capable scattering coefficients that satisfy condition of y=0 and corresponding height at last;
Step 8, obtain the primary data of whole audience scape prediction;
According to the method for step 6 and step 7, obtain y=1 ... all scattering coefficients that satisfy condition of 6 row and corresponding height;
Step 9, carry out the sliding window prediction of whole audience scape;
The window length of getting height value equally is 7, gets the height value h (x that obtains to slip along y this moment
i, y
j), i=0 wherein ... 128, j=0 ... 128; Repeat the Forecasting Methodology of using step 5 identical, obtain the maximum backscattering coefficient σ that all satisfy condition with step 6
Max(xi, yj) and corresponding height h (x
i, y
j);
Step 10, obtain the final imaging of bistatic linear-array three-dimensional imaging synthetic aperture radar;
In order to reduce to predict the error of imaging, to the height value h (x that obtains through above-mentioned steps
i, y
j) to carry out window be 7 * 7 two dimension median filter for the matrix H formed, the function of two dimension median filter in MATLAB7.0 is medfilt2 (), and the height matrix that obtains the final imaging of bistatic linear-array three-dimensional imaging synthetic aperture radar is H and corresponding backscattering coefficient matrix σ thereof as a result;
Through aforesaid operations, just can obtain quickly imaging for double-linear-array three-dimensional imaging synthetic aperture radar.
Need to prove, according to existing bistatic linear-array three-dimensional imaging synthetic aperture radar system scheme and bistatic linear-array three-dimensional imaging synthetic aperture radar observation scheme, the quickly imaging for double-linear-array three-dimensional imaging synthetic aperture radar method needs be initialized to be as systematic parameter known.See document " two stations synthetic aperture radar image-forming principle " for details, Tang Ziyue etc. write, and Science Press publishes.
In the regularity of distribution of the synthetic-aperture radar backscattering coefficient of mentioning, having chosen Rayleigh in the above---Bei Saier distributes, and for other backscattering coefficient regularity of distribution under the different scenes, for example Wei Buer distributes, Gaussian distribution etc., this method is effective equally.
In the application of reality, irradiation area according to radar reality, the scattering point that comprises echo in the three-dimensional imaging scene only comprises the scattering point on certain particular curvature in the three dimensions, therefore, the imaging problem of bistatic linear-array three-dimensional imaging synthetic aperture radar can be converted into the curved surface forecasting problem based on certain particular curvature.
Innovative point of the present invention is at the characteristics that only comprise the echoed signal of certain particular curvature in the three dimensions in the actual bistatic linear-array three-dimensional imaging synthetic aperture radar return, adopt self-adaptation curved surface forecasting techniques, only the particular curvature in the three dimensions is carried out imaging processing, compare with processing of existing branch dimension and three dimensions frequency domain Processing Algorithm, this algorithm has littler operand, thereby has well solved the big problem of two station three-dimensional imaging synthetic aperture radar formation method operands.
The present invention is directed to these characteristics of echoed signal that only comprise the scattering point on certain particular curvature in the three dimensions in the actual bistatic linear-array three-dimensional imaging synthetic aperture radar return, adopt the adaptive threshold detection technique, carry out curved surface prediction imaging processing at certain particular curvature in the three dimensions, thereby well solved the big problem of bistatic linear-array three-dimensional imaging synthetic aperture radar imaging method operand.
The invention has the advantages that and utilize less operand to realize the bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional imaging.Compare with existing three-dimensional imaging synthetic aperture radar imaging algorithm, algorithm operation quantity of the present invention is about 1/10th of existing algorithm.The present invention can be applied to fields such as synthetic aperture radar image-forming, earth remote sensing.
Description of drawings
Fig. 1 is existing bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional rear orientation projection imaging side block diagram
Wherein, passage i represents the echo data of i antenna of receiver linear array antenna, i=1 ..., M.M represents the antenna channels sum, and PRF represents radar pulse repetition frequency, and n represents radar transmitted pulse number, R
i(n; P
Uvw) represent that the transmitter antenna phase center is apart from scattering point P
UvwDistance, R
r(n, i; P
Uvw) represent that i radar receiving antenna of linear array receiver is apart from scattering point P
UvwDistance, (u, v w) are the coordinate of scattering point.The dual-mode antenna phase center can be calculated by the initiation parameter of step 1 in the instructions.The linear-array three-dimensional imaging synthetic aperture radars image space that the 3-D view space is described for definition 3.Synthetic-aperture radar gauged distance compression method apart from boil down to definition 2 descriptions.Interpolation/resampling and coherent accumulation are the standard method of two-dimentional rear orientation projection formation method.
Fig. 2 is the height matrix diagram of existing curved surface Forecasting Methodology
The figure shows the height matrix diagram of bistatic linear-array three-dimensional imaging.Directions X is for cutting velocity reversal, and y is to being along velocity reversal.Zone 1 is initialized 7 * 7 zonules, the primary data along x direction height value of zone 2 for obtaining by the prediction searching method, the whole audience scape height value data along y direction of zone 3 for obtaining by the prediction searching method.
Fig. 3 is the block scheme of method provided by the present invention
Wherein, DEM represents digital height map, F﹠amp; P﹠amp; S represents " surface fitting, prediction and maximum value search ".
The bistatic linear-array three-dimensional imaging synthetic aperture radar flight geometric relationship figure of Fig. 4 for adopting for the specific embodiment of the invention
Wherein, the PRI indicating impulse repetition period, Tx represents the transmitter antenna phase center, and Rx-APC represents i receiver antenna phase center, R
i(n; P
ω) represent that the transmitter antenna phase center is apart from scattering point P
ωDistance, R
r(n, i; P
ω) represent that i radar receiving antenna of linear array receiver is apart from scattering point P
ωDistance, (u, v w) are scattering point P
ωCoordinate system, (x, y z) are the coordinate system of carrier aircraft platform,
For sending out, receive platform speed vector, θ
i, θ
rFor sending out, receive antenna phase center to scattering point P
ωThe depression angle.
Fig. 5 is the bistatic linear-array three-dimensional imaging synthetic aperture radar system parameter list that the specific embodiment of the invention adopts
Fig. 6 is a process flow diagram of the present invention
Wherein BLASAR represents the bistatic linear-array three-dimensional imaging synthetic aperture radar.
Embodiment
The present invention mainly adopts the method for emulation experiment to verify, institute in steps, conclusion all on MATLAB7.0 checking correct.Concrete implementation step is as follows:
The systematic parameter that this embodiment adopted sees Fig. 5 for details.
Adopt synthetic-aperture radar gauged distance compression method to the synthetic aperture distance by radar to echo data D
eCompress, obtain the bistatic linear-array three-dimensional imaging synthetic aperture radar data after distance is compressed, note is E
c
Adopting bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, is the regional Ω of 7 * 7 * H (H is the reference altitude of imaging scene) to zone in the bistatic linear-array three-dimensional imaging synthetic aperture radar image space
0={ (x
i, y
j, h) | i=0 ... 6, j=0 ... 6, h ∈ [H/2, H/2] } in institute carry out imaging a little and handle, obtain that the zone is Ω in the bistatic linear-array three-dimensional imaging synthetic aperture radar image space
0The interior backscattering coefficient of being had a few also is that bistatic linear-array three-dimensional imaging synthetic aperture racon collection is
In institute have a few the edge highly to the distribution function of backscattering coefficient, note is done: σ (x, y, h).
To index set
Pairing backscattering coefficient distribution function along height to adopt the traversal method to search for to obtain distribution function along height to the scattering coefficient maximal value and the height at corresponding maximal value place with it; Wherein, two stations synthetic-aperture radar along the height to backscattering coefficient distribution function σ (x, y, h) maximal value σ
Max(x, y) expression, and corresponding highly with h (x, y) expression;
Step 4, along x to highly carrying out match prediction;
Altitude information h (the x that the polynomial fitting method of employing standard is capable to known y=0
i, 0), i=0 ... 6 carry out fitting of a polynomial, and our exponent number of selecting match is 3 herein, promptly carries out three rank surface fitting and predictions, obtains fitting function h=f (x), and x=7 is brought into fitting function h=f (x), obtains pre-computed altitude h
p(7,0);
According to the regularity of distribution of the backscattering coefficient of synthetic-aperture radar, choose Rayleigh---Bezier distributes.Set false-alarm probability α or detection probability δ, go out detection threshold θ according to false-alarm probability distribution function or detection probability distribution function and Threshold detection technique computes.Here the distribution function of our known detection probability is a Rayleigh---Bessel's function, obtain detection threshold by average and the variance of calculating this function.
The backscattering coefficient maximal value σ that obtains according to step 3
Max(x y), chooses the capable σ of y=0
Max(x
i, 0), i=0 ... 6, calculate the intermediate value and the variances sigma of this class value respectively
Med, s
σ, utilize formula
Obtain the average amplitude ss, according to the three dB bandwidth detection criteria,
Be probability average, the s of distribution function
σBe its variance.
Setting detection probability is 0.8, utilizes the Threshold detection technology, and we obtain detection threshold θ;
The true altitude of step 6, search bistatic linear-array three-dimensional imaging synthetic aperture radar map picture point;
Adopt bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, to the point in the three-dimensional imaging space (7,0, h
p) carry out imaging, obtain point (7,0, h
p) backscattering coefficient σ (7,0, h
p).
When σ (7,0, h
p)＜θ carries out upstream operation, and upstream operation is defined as and adopts bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, at point (x, y is h) under the situation of imaging, to being arranged in the point (x of imaging space, y, h+k Δ h), imaging is carried out in k 〉=1.Therefore earlier to the point in the three-dimensional imaging space (7,0, h
p+ Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p+ Δ h), wherein Δ h be the bistatic linear-array three-dimensional imaging synthetic aperture radar along height to resolution.Judgement σ (7,0, h
p+ Δ h) whether greater than thresholding θ, if σ (7,0, h
p+ Δ h)＞θ, adopt bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, to the point in the three-dimensional imaging space (7,0, h
p+ 2 Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p+ 2 Δ h), when σ (7,0, h
p+ 2 Δ h)＜and σ (7,0, h
p+ Δ h), jumps out this search, and get σ
Max(7,0)=σ (7,0, h
p+ Δ h), h (7,0)=h+ Δ h, when σ (7,0, h
p+ 2 Δ h)＞and σ (7,0, h
p+ Δ h), to point (7,0, h
p+ 3 Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p+ 3 Δ h), when σ (7,0, h
p+ 3 Δ h)＜and σ (7,0, h
p+ 2 Δ h), jump out this search, and get σ
Max(7,0)=σ (7,0, h
p+ 2 Δ h), h (7,0)=h+2 Δ h, when σ (7,0, h
p+ 2 Δ h)＜and σ (7,0, h
p+ Δ h), continue this upstream operation, until be met condition σ (7,0, h
p+ (k-1) Δ h)＜and σ (7,0, h
p+ k Δ h)＞and σ (7,0, h
p+ (k+1) Δ h) k value, this seasonal σ
Max(7,0)=σ (7,0, h
p+ k Δ h), h (7,0)=h+k Δ h; When σ (7,0, h
p+ Δ h)＜and θ, carry out downstream operation, downstream operation is defined as and adopts bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, at point (x, y is h) under the situation of imaging, to being arranged in the point (x of imaging space, y, h+k Δ h), imaging is carried out in k≤-1.Therefore to point (7,0, h
p-Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p-Δ h), if σ (7,0, h
p-Δ h)＞θ, to point (7,0, h
p-2 Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p-2 Δ h), if σ (7,0, h
p-2 Δ h)＜and σ (7,0, h
p-Δ h), jumps out this search, and make σ
Max(7,0)=σ (7,0, h
p-Δ h), h (7,0)=h-Δ h, when σ (7,0, h
p-2 Δ h)＞and σ (7,0, h
p-Δ h), to point (7,0, h
p-3 Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p-3 Δ h), when σ (7,0, h
p-3 Δ h)＜and σ (7,0, h
p-2 Δ h), jump out this search, and get σ
Max(7,0)=σ (7,0, h
p-2 Δ h), h (7,0)=h-2 Δ h, when σ (7,0, h
p-3 Δ h)＞and σ (7,0, h
p-2 Δ h) continue this downstream operation, until be met condition σ (7,0, h
p-(k-1) Δ h)＜and σ (7,0, h
p-k Δ h)＞and σ (7,0, h
p-(k+1) Δ h) k value, this seasonal σ
Max(7,0)=σ (7,0, h
p-k Δ h), h (7,0)=h-k Δ h; K=2 wherein ... Δ hH/2; When σ (7,0, h
p-Δ h)＜θ, change the upstream operation at k=2 place over to, when σ (7,0, h
p+ 2 Δ h)＜and θ, change the downstream operation at k=2 place over to, alternatively up and down search like this is until searching backscattering coefficient and the corresponding height value that satisfies condition; When not searching the backscattering coefficient that satisfies condition, get the final height of the height value of backscattering coefficient maximum as imaging.
When σ (7,0, h
p)＞θ adopts bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, to point (7,0, h
p+ Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p+ Δ h), to the point in the three-dimensional imaging space (7,0, h
p-Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p-Δ h), Δ h meaning is the same; When σ (7,0, h
p-Δ h)＜and σ (7,0, h
p)＞σ (7,0, h
p+ Δ h), jumps out this search, and get σ
Max(7,0)=σ (7,0, h
p), h (7,0)=h; When σ (7,0, h
p-Δ h)＜and σ (7,0, h
p)＜σ (7,0, h
p+ Δ h), enters the upstream operation of narrating above, until backscattering coefficient that obtains to satisfy condition and corresponding height value; When σ (7,0, h
p-Δ h)＞and σ (7,0, h
p)＞σ (7,0, h
p+ Δ h), enters the downstream operation of narrating above, until backscattering coefficient that obtains to satisfy condition and corresponding height value; When σ (7,0, h
p-Δ h)＞and σ (7,0, h
p)＜σ (7,0, h
p+ Δ h), enters full-height search, and get maximum scattering coefficient and corresponding height thereof as scattering coefficient that satisfies condition and height; When carrying out upstream operation or downstream operation, not jumping out search, then get scattering coefficient and height that maximum scattering coefficient and corresponding height conduct thereof satisfy condition equally.
After the above-mentioned operation steps of process, we obtain the maximum backscattering coefficient σ with curve fitting and Forecasting Methodology
Max(7,0) and corresponding height h (7,0);
Step 7, based on the full line prediction of sliding window;
The window length of getting height value is 7, promptly obtains one group of new height value h (x along x to slip
i, 0), i=1 ... 7, repeat the Forecasting Methodology of using step 5 identical with step 6, be met the maximum backscattering coefficient σ of condition
Max(8,0) and corresponding height h (8,0) slide window position so successively, obtain all capable scattering coefficients that satisfy condition of y=0 and corresponding height at last;
Step 8, obtain the primary data of whole audience scape prediction;
According to the method for step 6 and step 7, obtain y=1 ... all scattering coefficients that satisfy condition of 6 row and corresponding height.
Step 9, carry out the sliding window prediction of whole audience scape;
The window length of getting height value equally is 7, gets the height value h (x that obtains to slip along y this moment
i, y
j), i=0 wherein ... 128, j=0 ... 128; Repeat the Forecasting Methodology of using step 5 identical, obtain the maximum backscattering coefficient σ that all satisfy condition with step 6
Max(x
i, y
j) and corresponding height h (x
i, y
j);
Step 10, obtain the final imaging of bistatic linear-array three-dimensional imaging synthetic aperture radar;
In order to reduce to predict the error of imaging, to the height value h (x that obtains through above-mentioned steps
i, y
j) to carry out window be 7 * 7 two dimension median filter for the matrix H formed, the height matrix that obtains the final imaging of bistatic linear-array three-dimensional imaging synthetic aperture radar is H and corresponding backscattering coefficient matrix σ thereof as a result.
In embodiment, by as can be known with the test of the emulation of technical solution of the present invention and simulation result, bistatic linear-array three-dimensional imaging synthetic aperture radar imaging method provided by the present invention can have been realized the bistatic linear-array three-dimensional imaging synthetic aperture radar imagery, dividing dimension processing and three dimensions frequency domain to handle imaging algorithm with existing three-dimensional imaging synthetic aperture radar compares, the present invention has only just finished imaging with a two-dimensional process, has littler operand.
Claims (1)
1, a kind of quickly imaging for double-linear-array three-dimensional imaging synthetic aperture radar method, it may further comprise the steps:
Step 1, initialization bistatic linear-array three-dimensional imaging synthetic aperture radar imagery systematic parameter:
Initialized imaging system parameter comprises: flat pad and receiving platform velocity
Platform initial position vector
The electromagnetic wave number of radar emission, note is K
c, the relative platform of each array element of receiver linear array antenna center, note is P
Ri, wherein i is each array element sequence number of antenna, is natural number, i=0, and 1 ..., M, M are each array element sum of receiver linear array antenna, the signal bandwidth of radar emission baseband signal, and note is B, the radar emission signal pulse width, note is T
p, radar receives the ripple door and continues width, and note is T
d, the sample frequency of radar receiving system, note is f
s, the pulse repetition rate of radar system, note is PRF, and receiving system reception ripple door is remembered and is T with respect to the delay of the transmitted wave door that transmits
DAbove-mentioned parameter is the canonical parameter of bistatic linear-array three-dimensional imaging synthetic aperture radar system, wherein, and the electromagnetic wave number K of radar emission
c, the signal bandwidth B of radar emission baseband signal, radar emission signal pulse width T
p, radar receives the ripple door and continues width T
d, the sample frequency f of radar receiving system
s, the pulse repetition rate PRF of radar system and receiving system receive the ripple door and determine in bistatic linear-array three-dimensional imaging synthetic aperture Radar Design process with respect to the delay of the transmitted wave door that transmits; Wherein, send out, receive the platform speed vector
And initial position vector
In bistatic linear-array three-dimensional imaging synthetic aperture radar observation conceptual design, determine;
Step 2, bistatic linear-array three-dimensional imaging synthetic aperture radar raw data are carried out the distance compression:
Adopt synthetic-aperture radar gauged distance compression method to the synthetic aperture distance by radar to echo data D
eCompress, obtain the bistatic linear-array three-dimensional imaging synthetic aperture radar data after distance is compressed, note is E
c
Step 3, the height that obtains continuous zonule in the bistatic linear-array three-dimensional imaging synthetic aperture racon collection and corresponding scattering coefficient maximal value, promptly initialized imaging region;
Adopting bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, is the regional Ω of 7 * 7 * H (H is the reference altitude of imaging scene) to zone in the bistatic linear-array three-dimensional imaging synthetic aperture radar image space
0={ (x
i, y
j, h) | i=0 ... 6, j=0 ... 6, h ∈ [H/2, H/2] } in institute carry out imaging a little and handle, obtain that the zone is Ω in the bistatic linear-array three-dimensional imaging synthetic aperture radar image space
0The interior backscattering coefficient of being had a few also is that bistatic linear-array three-dimensional imaging synthetic aperture racon collection is Ξ
0={ z|z=h (x
i, y
j), i=0 ... 6, j=0 ... institute in the 6} have a few the edge highly to the distribution function of backscattering coefficient, note is done: σ (x, y, h);
To index set Ξ
0Pairing backscattering coefficient distribution function along height to adopt the traversal method to search for to obtain distribution function along height to the scattering coefficient maximal value and the height at corresponding maximal value place with it; Wherein, two stations synthetic-aperture radar along the height to backscattering coefficient distribution function σ (x, y, h) maximal value σ
Max(x, y) expression, and corresponding highly with h (x, y) expression;
Step 4, along x to highly carrying out match prediction;
Altitude information h (the x that the polynomial fitting method of employing standard is capable to known y=0
i, 0), i=0 ... 6 carry out fitting of a polynomial, and our exponent number of selecting match is 3 herein, promptly carries out three rank surface fitting and predictions, obtains fitting function h=f (x), and x=7 is brought into fitting function h=f (x), obtains pre-computed altitude h
p(7,0);
Step 5, obtain detection threshold;
According to the regularity of distribution of the backscattering coefficient of synthetic-aperture radar, choose Rayleigh---Bezier distributes; Set false-alarm probability α or detection probability δ, go out detection threshold θ according to false-alarm probability distribution function or detection probability distribution function and Threshold detection technique computes; Here the distribution function of our known detection probability is a Rayleigh---Bessel's function, obtain detection threshold by average and the variance of calculating this function;
The backscattering coefficient maximal value σ that obtains according to step 3
Max(x y), chooses the capable σ of y=0
Max(x
i, 0), i=0 ... 6, calculate the intermediate value and the variances sigma of this class value respectively
Med, s
σ, utilize formula
Obtain the average amplitude ss, according to the three dB bandwidth detection criteria,
Be probability average, the s of distribution function
σBe its variance;
Setting detection probability is 0.8, utilizes the Threshold detection technology, and we obtain detection threshold θ;
The true altitude of step 6, search bistatic linear-array three-dimensional imaging synthetic aperture radar map picture point;
Adopt bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, to the point in the three-dimensional imaging space (7,0, h
p) carry out imaging, obtain point (7,0, h
p) backscattering coefficient σ (7,0, h
p);
When σ (7,0, h
p)＜θ carries out upstream operation, and upstream operation is defined as and adopts bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, at point (x, y is h) under the situation of imaging, to being arranged in the point (x of imaging space, y, h+k Δ h), imaging is carried out in k 〉=1; Therefore earlier to the point in the three-dimensional imaging space (7,0, h
p+ Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p+ Δ h), wherein Δ h be the bistatic linear-array three-dimensional imaging synthetic aperture radar along height to resolution; Judgement σ (7,0, h
p+ Δ h) whether greater than thresholding θ, if σ (7,0, h
p+ Δ h)＞θ, adopt bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, to the point in the three-dimensional imaging space (7,0, h
p+ 2 Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p+ 2 Δ h), when σ (7,0, h
p+ 2 Δ h)＜and σ (7,0, h
p+ Δ h), jumps out this search, and get σ
Max(7,0)=σ (7,0, h
p+ Δ h), h (7,0)=h+ Δ h, when σ (7,0, h
p+ 2 Δ h)＞and σ (7,0, h
p+ Δ h), to point (7,0, h
p+ 3 Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p+ 3 Δ h), when σ (7,0, h
p+ 3 Δ h)＜and σ (7,0, h
p+ 2 Δ h), jump out this search, and get σ
Max(7,0)=σ (7,0, h
p+ 2 Δ h), h (7,0)=h+2 Δ h, when σ (7,0, h
p+ 2 Δ h)＜and σ (7,0, h
p+ Δ h), continue this upstream operation, until be met condition σ (7,0, h
p+ (k-1) Δ h)＜and σ (7,0, h
p+ k Δ h)＞and σ (7,0, h
p+ (k+1) Δ h) k value, this seasonal σ
Max(7,0)=σ (7,0, h
p+ k Δ h), h (7,0)=h+k Δ h; When σ (7,0, h
p+ Δ h)＜and θ, carry out downstream operation, downstream operation is defined as and adopts bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, at point (x, y is h) under the situation of imaging, to being arranged in the point (x of imaging space, y, h+k Δ h), imaging is carried out in k≤-1; Therefore to point (7,0, h
p-Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p-Δ h), if σ (7,0, h
p-Δ h)＞θ, to point (7,0, h
p-2 Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p-2 Δ h), if σ (7,0, h
p-2 Δ h)＜and σ (7,0, h
p-Δ h), jumps out this search, and make σ
Max(7,0)=σ (7,0, h
p-Δ h), h (7,0)=h-Δ h, when σ (7,0, h
p-2 Δ h)＞and σ (7,0, h
p-Δ h), to point (7,0, h
p-3 Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p-3 Δ h), when σ (7,0, h
p-3 Δ h)＜and σ (7,0, h
p-2 Δ h), jump out this search, and get σ
Max(7,0)=σ (7,0, h
p-2 Δ h), h (7,0)=h-2 Δ h, when σ (7,0, h
p-3 Δ h)＞and σ (7,0, h
p-2 Δ h) continue this downstream operation, until be met condition σ (7,0, h
p-(k-1) Δ h)＜and σ (7,0, h
p-k Δ h)＞and σ (7,0, h
p-(k+1) Δ h) k value, this seasonal σ
Max(7,0)=σ (7,0, h
p-k Δ h), h (7,0)=h-k Δ h; K=2 wherein ... Δ hH/2; When σ (7,0, h
p-Δ h)＜θ, change the upstream operation at k=2 place over to, when σ (7,0, h
p+ 2 Δ h)＜and θ, change the downstream operation at k=2 place over to, alternatively up and down search like this is until searching backscattering coefficient and the corresponding height value that satisfies condition; When not searching the backscattering coefficient that satisfies condition, get the final height of the height value of backscattering coefficient maximum as imaging;
When σ (7,0, h
p)＞θ adopts bistatic linear-array three-dimensional imaging synthetic aperture radar three-dimensional back projection formation method, to point (7,0, h
p+ Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p+ Δ h), to the point in the three-dimensional imaging space (7,0, h
p-Δ h) carry out imaging, obtain this point backscattering coefficient σ (7,0, h
p-Δ h), Δ h meaning is the same; When σ (7,0, h
p-Δ h)＜and σ (7,0, h
p)＞σ (7,0, h
p+ Δ h), jumps out this search, and get σ
Max(7,0)=σ (7,0, h
p), h (7,0)=h; When σ (7,0, h
p-Δ h)＜and σ (7,0, h
p)＜σ (7,0, h
p+ Δ h), enters the upstream operation of narrating above, until backscattering coefficient that obtains to satisfy condition and corresponding height value; When σ (7,0, h
p-Δ h)＞and σ (7,0, h
p)＞σ (7,0, h
p+ Δ h), enters the downstream operation of narrating above, until backscattering coefficient that obtains to satisfy condition and corresponding height value; When σ (7,0, h
p-Δ h)＞and σ (7,0, h
p)＜σ (7,0, h
p+ Δ h), enters full-height search, and get maximum scattering coefficient and corresponding height thereof as scattering coefficient that satisfies condition and height; When carrying out upstream operation or downstream operation, not jumping out search, then get scattering coefficient and height that maximum scattering coefficient and corresponding height conduct thereof satisfy condition equally;
After the above-mentioned operation steps of process, we obtain the maximum backscattering coefficient σ with curve fitting and Forecasting Methodology
Max(7,0) and corresponding height h (7,0);
Step 7, based on the full line prediction of sliding window;
The window length of getting height value is 7, promptly obtains one group of new height value h (x along x to slip
i, 0), i=1 ... 7, repeat the Forecasting Methodology of using step 5 identical with step 6, be met the maximum backscattering coefficient σ of condition
Max(8,0) and corresponding height h (8,0) slide window position so successively, obtain all capable scattering coefficients that satisfy condition of y=0 and corresponding height at last;
Step 8, obtain the primary data of whole audience scape prediction;
According to the method for step 6 and step 7, obtain y=1 ... all scattering coefficients that satisfy condition of 6 row and corresponding height;
Step 9, carry out the sliding window prediction of whole audience scape;
The window length of getting height value equally is 7, gets the height value h (x that obtains to slip along y this moment
i, y
j), i=0 wherein ... 128, j=0 ... 128; Repeat the Forecasting Methodology of using step 5 identical, obtain the maximum backscattering coefficient σ that all satisfy condition with step 6
Max(x
i, y
j) and corresponding height h (x
i, y
j);
Step 10, obtain the final imaging of bistatic linear-array three-dimensional imaging synthetic aperture radar;
In order to reduce to predict the error of imaging, to the height value h (x that obtains through above-mentioned steps
i, y
j) to carry out window be 7 * 7 two dimension median filter for the matrix H formed, the function of two dimension median filter in MATLAB7.0 is medfilt2 (), and the height matrix that obtains the final imaging of bistatic linear-array three-dimensional imaging synthetic aperture radar is H and corresponding backscattering coefficient matrix σ thereof as a result;
Through aforesaid operations, just can obtain quickly imaging for double-linear-array three-dimensional imaging synthetic aperture radar.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101833095A (en) * | 2010-04-14 | 2010-09-15 | 电子科技大学 | Star machine united SAR (Synthetic Aperture Radar) two-dimensional frequency domain imaging method based on airspace domain expansion |
| CN109407094A (en) * | 2018-12-11 | 2019-03-01 | 湖南华诺星空电子技术有限公司 | Vehicle-mounted ULTRA-WIDEBAND RADAR forword-looking imaging system |
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| CN117630937A (en) * | 2024-01-26 | 2024-03-01 | 电子科技大学长三角研究院(湖州) | Scattering aperture imaging method, device and system and storage medium |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN100365429C (en) * | 2004-11-05 | 2008-01-30 | 清华大学 | Motive target imaging method of synthetic aperture radar |
| CN100561250C (en) * | 2006-09-29 | 2009-11-18 | 清华大学 | The clutter base-band analog signal production method of spaceborne bistatic radar |
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2008
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101833095A (en) * | 2010-04-14 | 2010-09-15 | 电子科技大学 | Star machine united SAR (Synthetic Aperture Radar) two-dimensional frequency domain imaging method based on airspace domain expansion |
| CN101833095B (en) * | 2010-04-14 | 2012-06-27 | 电子科技大学 | Star machine united SAR (Synthetic Aperture Radar) two-dimensional frequency domain imaging method based on airspace domain expansion |
| CN109407094A (en) * | 2018-12-11 | 2019-03-01 | 湖南华诺星空电子技术有限公司 | Vehicle-mounted ULTRA-WIDEBAND RADAR forword-looking imaging system |
| CN114627148A (en) * | 2021-07-05 | 2022-06-14 | 广东省科学院广州地理研究所 | Coastal zone aquaculture water body object extraction method and device based on microwave remote sensing |
| CN114627148B (en) * | 2021-07-05 | 2024-01-02 | 广东省科学院广州地理研究所 | Method and device for extracting coastal zone aquaculture water body object based on microwave remote sensing |
| CN117630937A (en) * | 2024-01-26 | 2024-03-01 | 电子科技大学长三角研究院(湖州) | Scattering aperture imaging method, device and system and storage medium |
| CN117630937B (en) * | 2024-01-26 | 2024-04-12 | 电子科技大学长三角研究院(湖州) | Scattering aperture imaging method, device and system and storage medium |
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