CN109814070A - Range ambiguity clutter suppression method based on false impulse - Google Patents
Range ambiguity clutter suppression method based on false impulse Download PDFInfo
- Publication number
- CN109814070A CN109814070A CN201910097128.7A CN201910097128A CN109814070A CN 109814070 A CN109814070 A CN 109814070A CN 201910097128 A CN201910097128 A CN 201910097128A CN 109814070 A CN109814070 A CN 109814070A
- Authority
- CN
- China
- Prior art keywords
- clutter
- domain
- indicate
- steering vector
- matrix
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Radar Systems Or Details Thereof (AREA)
Abstract
The invention discloses the range ambiguity clutter suppression methods based on false impulse, in FDA-MIMO constitution radar, utilize different distributions characteristic of the clutter of each fuzzy distance after carrying out distance dependencies frequency compensation on send-receive domain, pass through transmitting false impulse and postpone received mode and obtains data covariance matrix except the first fuzzy region clutter, it is filtered on the basis of traditional JDL dimensionality reduction matrix by the covariance matrix, can reinforce adjusting the distance the inhibition of fuzzy clutter, simultaneously because the on-fixed weight coefficient filtering based on the data that false impulse obtains, inhibitory effect can reduce the susceptibility of array error, therefore, the method of the present invention has the effect of more outstanding clutter recognition under conditions of there are array element error.
Description
Technical field
The invention belongs to signal processing technology fields, more particularly to the range ambiguity clutter recognition side based on false impulse
Method.
Background technique
Compared to traditional phased-array radar, multiple-input and multiple-output (MIMO) radar has a variety of advantages.MIMO radar
Difference transmitting array element emits mutually orthogonal waveform, and receives above array element in each of receiving end respectively to each hair
The echo for penetrating array element is handled, and therefore, MIMO technology can greatly expand the angle scanning range of radar, and different angle
Send-receive domain wave beam can carry out Wave beam forming simultaneously.
With the development of high-speed aircraft, high pulse repetition frequency, which can mitigate doppler ambiguity bring, to be influenced, but with
Caused by range ambiguity clutter problem be radar signal processing field a great problem, serious range ambiguity clutter problem will
The clutter recognition effect that will lead to high speed platform sharply deteriorates, and common MIMO radar is difficult to solve such problem.
In recent years, frequency diversity array (FDA) gradually steps into the sight of people.FDA is introduced between each transmitting array element
Small frequency interval for carrier frequency.FDA radar is related to distance on transmitting pattern, therefore gives entire thunder
The freedom degree in distance dimension is brought up to system.By FDA in conjunction with MIMO technology, it can be filled by the freedom degree using transmitting domain
Divide the freedom degree above using distance dimension, sufficiently inhibits range ambiguity clutter apart from three-dimensional adaptive method when passing through sky.When empty
The sample number needed apart from three-dimensional adaptive method is relatively more, and traditional local Combined Treatment (JDL) method is that a kind of comparison has
The dimension reduction method of effect, method is in the main beam several wave beams selected around closed on as accessory channel, by constructing JDL
Dimensionality reduction matrix carries out self-adaptive processing after transforming data to wave-number domain, effectively reduces independent same point that entire method needs
Cloth sample number, enable FDA-MIMO radar dimensionality reduction sky when effectively used in practice apart from adaptive approach.
Range ambiguity clutter cannot be distinguished in existing clutter suppression method, and increases the space-time adaptive of pitching dimension freedom degree
Algorithm can inhibit range ambiguity clutter to a certain extent, but since which increase the freedom degree that pitching is tieed up, calculation amount exists
It is difficult to realize in real time environment.And the method for using FDA-MIMO system at present, although range ambiguity clutter can be inhibited, with
The aggravation of array element error, clutter recognition penalty it is extremely serious.
Summary of the invention
To solve the above-mentioned problems, the purpose of the present invention is to propose to the range ambiguity clutter recognition sides based on false impulse
Method, technical principle of the invention is: in FDA-MIMO constitution radar, using each fuzzy distance clutter carry out distance according to
Different distributions characteristic after relying resistant frequency to compensate on send-receive domain by transmitting false impulse and postpones received side
Formula obtains the data covariance matrix for removing the first fuzzy region clutter, by the covariance matrix in traditional JDL dimensionality reduction matrix
On the basis of be filtered, so that this method is had the effect of more outstanding clutter recognition under conditions of there are array element error.
In order to achieve the above object, the present invention is resolved using following technical scheme.
Range ambiguity clutter suppression method based on false impulse, comprising the following steps:
Step 1, setting FDA-MIMO radar has M transmitting array element and N number of reception array element, and continues in K pulse
Sampling obtains M × N × K dimension practical steering vector a (λ of send-receive-Doppler0,rl,p,ψl,p,q,vl,p,q)；
Wherein, λ0For carrier wavelength, l indicates first of range gate, and p indicates pth range ambiguity region, and q indicates to dissipate for q-th
Exit point, rl,pIndicate the distance of first of range gate on pth range ambiguity region, ψl,p,qIt indicates on pth range ambiguity region first
The airspace cone angle of q-th of scattering point in range gate, vl,p,qIndicate q-th on pth range ambiguity region in first of range gate
Radial velocity of the movement velocity of scattering point with respect to radar；
Step 2, according to the practical steering vector a (λ of send-receive-Doppler0,rl,p,ψl,p,q,vl,p,q), obtain FDA-
The N of MIMO radarpA range ambiguity region clutter data C；
NpThe l of a range ambiguity region clutter data C is classified as cl, clFor the clutter data of first of range gate,
Wherein, CNR is the clutter noise power ratio being arranged when emulation, NpIndicate the sum in range ambiguity region, NcExpression pair
Answer the clutter scattering unit sum in range ambiguity region；nlFor the noise introduced when being sampled to first of range gate, the noise
Distribution form be M × N × K dimension white Gaussian noise, power 1；ξl,p,qIndicate the l on p-th of range ambiguity region
The scattering coefficient of q-th of clutter scattering unit in a range gate, scattering coefficient ξl,p,qObeying mean value is 0, the Gauss that variance is 1
Distribution.
Step 3, FDA-MIMO radar emission false impulse, since second false impulse repetition period, to auxiliary arteries and veins
The echo of punching carries out sampling and matched filtering, obtains the clutter data C of removal first distance fuzzy region-1,n, n=2 ..., NP。
Remove the clutter data C of first distance fuzzy region-1,nL be classified as c-1,n,l, c-1,n,lIt is first of range gate
Echo data,
Wherein, a'(λ ', rl,p,ψl,n,q) be false impulse steering vector, λ ' be the carrier wavelength answered of auxiliary pulse pair.
Step 4, by NpThe clutter data C of a range ambiguity region clutter data C and removal first distance fuzzy region-1,n
Transmitting domain frequency distance dependence compensation is carried out for first distance fuzzy region respectively, obtains compensated NpA range ambiguity
Region clutter data CcWith the clutter data C of compensated removal first distance fuzzy regionc -1,n。
Step 5, target detection position is chosen, according to the space cone angle cosine value cos ψ at target detection positiont, sent out
Penetrate-receive domain transformation matrix Ts；
Wherein,Indicate Kronecker product；ψtFor the space cone angle at target detection position, ψ1With ψ2For accessory channel institute
The space cone angle of selection, atc(λ0,ψt) indicate target
The process of inspection positions is apart from the compensated transmitting domain steering vector of dependent Frequency, atc(λ0,ψ1) representation space cone angle ψ1Place
By apart from the compensated transmitting domain steering vector of dependent Frequency, atc(λ0,ψ2) representation space cone angle ψ2Place is relied on by distance
Transmitting domain steering vector after frequency compensation, ar(λ0,ψt) indicate target detection position at reception domain steering vector, ar(λ0,
ψ1) representation space cone angle ψ1The reception domain steering vector at place, ar(λ0,ψ2) representation space cone angle ψ2The reception domain steering vector at place.
Step 6, using the clutter data C of compensated removal first distance fuzzy region-1,nCarry out send-receive domain
Covariance matrix, the covariance matrix in the send-receive domain estimated
Wherein, ()HThe conjugate transposition of representing matrix, L are Matrix C-1,nColumns and range gate number,For
The power of noise, IMNFor the unit matrix of M × N row M × N column.
Step 7, using the covariance matrix in the send-receive domain of estimationTo send-receive domain transformation matrix TsInto
Row filtering processing, obtains dimensionality reduction matrix Tsd；
Step 8, according to compensated NpA range ambiguity region clutter data Cc, using dimensionality reduction matrix TsdWhen carrying out empty away from
From self-adaptive processing, weight vector w is obtained:
Wherein, vtFor the relative radial rate between target to be detected and radar, α is constant；Using weight vector w into
Row filtering processing.
Compared with prior art, the invention has the benefit that
The present invention obtains auxiliary clutter number by transmitting false impulse by using the FDA-MIMO system of auxiliary waveform
According to the covariance matrix obtained by auxiliary clutter data is further filtered on the basis of traditional JDL transformation matrix, with biography
The JDL method of system is compared, and the method for the present invention on-fixed weight coefficient filtering based on the data that false impulse obtains, inhibitory effect is poised for battle
The susceptibility of column error significantly reduces, thus make this method than traditional JDL method there are larger array element error away from
It is more preferable from fuzzy clutter recognition effect；And with the increase of error, the clutter recognition effect of the more traditional JDL method of the method for the present invention
Superiority becomes apparent from.
Detailed description of the invention
The present invention is described in further details in the following with reference to the drawings and specific embodiments.
Fig. 1 is the flow diagram of the range ambiguity clutter suppression method of the invention based on false impulse.
Fig. 2 is the model schematic of FDA-MIMO radar of the present invention.
Fig. 3 is the embodiment simulation result diagram of the range ambiguity clutter suppression method of the invention based on false impulse.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
The embodiment of the present invention and effect are described in further detail with reference to the accompanying drawing.
Assuming that FDA-MIMO radar has M transmitting array element, N number of reception array element, between M transmitting array element between be divided into
dt, between N number of reception array element between be divided into dr, the difference of the frequency between adjacent transmission array element is △ f, the load of m-th of transmitting array element
Frequency fm=f0+ (m-1) △ f, first corresponding carrier wavelength of transmitting array element are λ0, respective frequencies f0, the pulse repetition of radar
Period is T, and radar is with vRSpeed along array orientation fly, radar work normally when emit K pulse.
Referring to Figures 1 and 2, the range ambiguity clutter suppression method of the invention based on false impulse realizes that steps are as follows:
(1) M × N × K dimension practical steering vector a (λ of send-receive-Doppler is obtained0,rl,p,ψl,p,q,vq)；
Sub-step 1a obtains ideal transmitting domain steering vector:
Wherein, j is imaginary unit, ft(λ0,rl,p,ψl,p,q) indicate the transmitting domain frequency that distance relies on, ft(λ0,rl,p,
ψl,p,qThe △ fr of)=- 2l,p/c+dtcos(ψl,p,q)/λ0, c is the light velocity, and △ f is the interval of FDA-MIMO radar emission carrier frequency, dtFor
Emit the location interval between array element, f in uniform line-array0For reference array element carrier frequency, ()TThe transposition of representing matrix.
Emit domain steering vector according to ideal, obtain removing the ideal transmitting domain steering vector after dependent Frequency are as follows:
Wherein, ftc(λ0,ψl,p,q) indicate transmitting domain frequency of the removal after dependent Frequency, ftc(λ0,ψl,p,q)=dtcos
(ψl,p,q)/λ0, ()TThe transposition of representing matrix.
Sub-step 1b obtains ideal reception domain steering vector:
Wherein, fr(λ0,ψl,p,q) indicate to receive domain frequency, fr(λ0,ψl,p,q)=drcos (ψl,p,q)/λ0。
Sub-step 1c obtains ideal Doppler domain steering vector:
Wherein, fd(ψl,p,q,vl,p,q) indicate Doppler domain frequency, fd(ψl,p,q,vl,p,q(the v of)=2l,p,q+vR)T cos
(ψl,p,q), vl,p,qSpeed, v are moved radially for the corresponding opposite radar of corresponding scattering unitRFor the movement velocity of radar, T is
Pulse repetition period.
Sub-step 1d, according to ideal transmitting domain steering vector, ideal reception domain steering vector and ideal Doppler domain guiding
Vector obtains M × N × K and ties up ideal steering vector:
Wherein,Indicate Kronecker product；
Sub-step 1e ties up ideal steering vector to M × N × K and carries out array element error introducing processing, obtains practical guiding arrow
Amount:
a(λ0,rl,p,ψl,p,q,vl,p,q)=D*ai(λ0,rl,p,ψl,p,q,vl,p,q),
Wherein, D indicates array element error matrix,
Column vector is placed on the main diagonal element of matrix by diag { } operator in order, remaining 0 composition square matrix of supplement；△
at,mIndicate the range error constant of m-th of transmitting array element, △ ar,nIndicate the range error constant of n-th of reception array element, △ at,m
With △ ar,nObeying mean value is 0, and standard deviation is the Gaussian Profile of margin of error X,Emit the phase error of array element for m-th
Constant,The phase error constant of array element is received for n-th,WithObeying mean value is 0, and coefficient is the equal of Y
Even distribution, 1KIndicate complete 1 K dimension column vector.
(2) according to the practical steering vector a (λ of send-receive-Doppler0,rl,p,ψl,p,q,vq), obtain the N of radarpIt is a away from
From fuzzy region clutter data C；
Radar is carrying out down coversion to echo, and sampling, digital mixing, after matched filtering, echo data is a matrix,
Each to arrange the data for representing a range gate, the number of range gate is l, namely the number of column.
The l of C is classified as cl, C is by clAccording to l from small to large by sequentially rearranging from left to right；
Wherein, clFor the clutter data of first of range gate, CNR is the clutter noise power ratio being arranged when emulation, NpIt indicates
The sum in range ambiguity region, NcIndicate the clutter scattering unit sum of respective distances fuzzy region；nlFor to first of range gate
The noise introduced when being sampled, the distribution form of the noise are M × N × K dimension white Gaussian noise, power 1；ξl,p,qIt indicates
The scattering coefficient of q-th of clutter scattering unit in first of range gate on p-th of range ambiguity region, scattering coefficient
ξl,p,qObeying mean value is 0, the Gaussian Profile that variance is 1.
(3) the clutter data C of removal first distance fuzzy region is obtained-1,n, n=2 ..., NP；
Specifically, FDA-MIMO radar emission false impulse, the false impulse use orthogonal frequency division multiplexing (OFDM) skill
Art, the false impulse waveform that each transmitting array element is sent out and all normal burst waves during the preceding K normal work in step 1
Shape is orthogonal, and during false impulse, mutually orthogonal between each transmitting array element waveform.Then, from second false impulse weight
The multiple period carries out sampling and matched filtering to the echo of false impulse, obtains the clutter of removal first distance fuzzy region
Data C-1,n, n=2 ..., NP；
C-1,nL be classified as c-1,n,l, C-1,nBy c-1,n,lIt is from left to right rearranged in order from small to large according to l,
Wherein,λ ' is the carrier wave for assisting pulse pair to answer
Wavelength, at(λ',rl,p,ψl,n,q) indicate false impulse transmitting domain steering vector, ar(λ',ψl,n,q) indicate connecing for false impulse
Receive domain steering vector；
ft(λ',rl,p,ψl,p,q) indicate false impulse transmitting domain frequency, expression formula are as follows:
ft(λ',rl,p,ψl,p,qThe △ fr of)=- 2l,p/c+dtcos(ψl,p,q)/λ'；
fr(λ',ψl,p,q) indicate false impulse reception domain frequency, fr(λ',ψl,p,q)=drcos(ψl,p,q)/λ'；
Each frequency shift amount △ f' for emitting the corresponding auxiliary waveform of array element meets the following conditions；
△f'≥B+(M-1)△f+BD,
(4) compensated N is obtainedpA range ambiguity region clutter data CcWith compensated removal first distance confusion region
The clutter data C in domain-1,n
Specific compensation process the following steps are included:
Sub-step 4a, construction compensation column vector gt(rl,1):
Sub-step 4b compensates Np range ambiguity region clutter data C using compensation column vector, after obtaining compensation
NpA range ambiguity region clutter data Cc, CcL column compensation after be cl c,
cl c=diag { gt(rl,1)}cl,
Wherein, when compensating, oblique distance rl,1With the clutter data C of removal first distance fuzzy region-1,nIn column phase
Matching, i.e., in rl,1In l and cc -1,n,lIn the identical situation of l under, compensate.To be after all column compensation in C
C is obtainedc。
Sub-step 4c, using compensation column vector to the clutter data C of removal first distance fuzzy region-1,nIt compensates,
Obtain the clutter data C of compensated removal first distance fuzzy region-1,n, C-1,nIt is compensated to be classified as cc -1,n,l,
cc -1,n,l=diag { gts(rl,1)}c-1,n,l(n=2 ..., Np),
Wherein, when compensating, oblique distance rl,1With the clutter data C of removal first distance fuzzy region-1,nIn column phase
Matching, i.e., in rl,1In l and cc -1,n,lIn the identical situation of l under, compensate.
(5) send-receive domain transformation matrix T is obtaineds；
Specifically, target detection position is chosen, according to the space cone angle cosine value cos ψ at target detection positiont, obtain
Send-receive domain transformation matrix Ts；
Wherein, ψtFor the space cone angle at target detection position, ψ1With ψ2For the selected space cone angle of accessory channel,atc(λ0,ψt) indicate target detection position at process
Apart from the compensated transmitting domain steering vector of dependent Frequency, atc(λ0,ψ1) representation space cone angle ψ1The process at place is apart from dependent Frequency
Compensated transmitting domain steering vector, atc(λ0,ψ2) representation space cone angle ψ2The process at place is apart from the compensated transmitting of dependent Frequency
Domain steering vector, ar(λ0,ψt) indicate target detection position at reception domain steering vector, ar(λ0,ψ1) representation space cone angle ψ1
The reception domain steering vector at place, ar(λ0,ψ2) representation space cone angle ψ2The reception domain steering vector at place.
(6) covariance matrix in the send-receive domain of estimation is obtained
Using the clutter data of compensated removal first distance fuzzy regionEmit-
Receive the covariance matrix in domain, the covariance matrix in the send-receive domain estimated
Wherein, ()HThe conjugate transposition of representing matrix, L are matrixColumns, that is to say and emulate range gate used
Number,For the power of noise, IMNFor the unit matrix of MN row MN column.
(7) dimensionality reduction matrix T is obtainedsd；
Using the covariance matrix in the send-receive domain of estimationTo send-receive domain transformation matrix TsIt is filtered place
Reason, obtains dimensionality reduction matrix Tsd；
Specifically, using the covariance matrix in the send-receive domain of estimationTo send-receive domain transformation matrix TsInto
Row filtering, obtains filtered send-receive domain transformation matrix T's:
Further according to filtered send-receive domain transformation matrix T's, obtain dimensionality reduction matrix Tsd:
Obtained dimensionality reduction matrix TsdIt is that tradition 3 × 3 × 3JDL dimensionality reduction matrix is filtered in auxiliary waveform data covariance matrix
Dimensionality reduction matrix after wave.Traditional JDL method can't be to TsIt is filtered, but directly uses TsCarry out follow-up signal processing.
Method of the invention and tradition JDL method the difference is that: the clutter in addition to the first fuzzy region is first obtained using false impulse
Then data estimate the clutter covariance matrix in addition to the first fuzzy region using these clutter datasFollowed byTo TsIt is filtered, the inhibition for the fuzzy clutter that can reinforce adjusting the distance after being filtered, simultaneously because based on auxiliary arteries and veins
Punching filters and on-fixed weight coefficient filters, and inhibitory effect can reduce the susceptibility of array error.
(8) to NpA range ambiguity region clutter is filtered
According to compensated NpA range ambiguity region clutter data Cc, using dimensionality reduction matrix TsdApart from adaptive when carrying out empty
It should handle, obtain weight vector w；Using weight vector w to NpA range ambiguity region clutter is filtered；
Detailed process is as follows:
Using weight vector w, the improvement factor IF under weight vector w is obtained:
According to the improvement factor IF and ideal improvement factor IF under weight vector wmax, obtain corresponding letter miscellaneous noise ratio loss
Value SCNRloss。
SCNRloss=IF-IFmax,
IFmax=10log (MNKCNR),
Wherein, trace { } representing matrix opposite line element summation operator, CNR indicate miscellaneous noise ratio, ()-1Square is sought in expression
Battle array it is inverse, b be target at corresponding steering vector,bTPass through dimensionality reduction for b
MatrixTreated goal orientation vector.
Specifically, a target detection speed vt, can correspond to obtain a weight vector w, and then obtain the target detection
The corresponding letter miscellaneous noise ratio of speed loses SCNRloss, in specific simulation process, make target detection speed vtAccording to a fixed step size
?Range value, then available letter miscellaneous noise ratio loss is examined with target
Degree of testing the speed vtRelation curve, according to normalization Doppler frequency calculation formula fd(ψt,vt(the v of)=2R+vt)Tcos(ψt), it can
To obtain the loss of letter miscellaneous noise ratio and normalization Doppler frequency fd(ψt,vt) relation curve, pass through the recess in the relation curve
Width can evaluate the Minimum detectable of radar, and the notch width of curve is smaller, illustrate that detectable minimum speed is got over
Small, then the rejection of clutter is more preferably.
Below using the method for the present invention to FDA-MIMO radar carry out range ambiguity clutter recognition emulation experiment, and with tradition
JDL method compare, emulation experiment parameter setting is as follows:
FDA-MIMO radar is with vpThe speed of=450m/s is flown, and element number of array M=6 is emitted, and receives element number of array N=6,
The carrier frequency f of first array element0=1GHz, wavelength X0=0.3m, difference on the frequency △ f=3KHz between array element, distance where object to be measured
Door position rt=20000m, object to be measured space ψ=0 cone angle cosine cos, radar flying height H=6000m, emulation it is used away from
Number L=500 from door, radar pulse waveform bandwidth B=6MHz, radar pulse repetition time T=during normal work
0.1ms, the range ambiguity number of regions N of considerationp=3, the clutter scattering unit number N on each rang ringc=181, radar emission arteries and veins
Rush number K=8.
Parameter setting such as table 1:
1 system emulation parameter of table
2, emulation content:
Under above-mentioned simulation parameter, under positive side view FDA-MIMO high speed platform environment, to the method for the present invention and tradition JDL
Method compares processing emulation, as a result as shown in Figure 3.
As seen from Figure 3, the simulation result that a is traditional JDL method when X be 0.1, Y is 10/180 π in Fig. 3；A ' is this
Simulation result of the inventive method when X be 0.1, Y is 10/180 π；B is traditional JDL method when X be 0.15, Y is 15/180 π
Simulation result；The simulation result that b ' is the method for the present invention when X be 0.15, Y is 15/180 π；It can be seen from the figure that a ' and b '
Curve is less than a and b in formula in the width of indent；Specifically, curve a and a ' is recessed when believing that miscellaneous noise ratio loss is -2.5dB
Mouth width degree is its Minimum detectable, and You Tuzhi, a ' corresponding notch width are smaller, and curve b and b ' is in letter miscellaneous noise ratio loss
Notch width when for -3.0dB is its Minimum detectable, You Tuzhi, b ' corresponding notch width is smaller, therefore, this hair
The Minimum detectable of bright method is smaller, and the clutter reduction effect for further relating to the method for the present invention is more preferable.
From figure 3, it can be seen that the resulting letter miscellaneous noise ratio loss of the embodiment of the present invention and normalization Doppler frequency curve
Increase of the notch width with channel amplitude margin of error X and phase error coefficient Y, the corresponding curve recess of false impulse JDL method
Width is consistently less than the curve notch width of traditional JDL method, illustrates that the method for the present invention is first obtained using false impulse except the first mould
The clutter data outside region is pasted, the clutter covariance matrix in addition to the first fuzzy region is then estimated using these clutter datasFollowed byTo TsIt is filtered, this method can reduce the Minimum detectable of radar, can be effective
Reinforce the inhibition of fuzzy clutter of adjusting the distance.Comparing each curve can be seen that increase with X and Y, i.e., with error degree plus
Deep, the letter miscellaneous noise ratio loss curve of traditional JDL method sink seriously in two sides, it is very violent to illustrate that detection performance deteriorates, but assist
The corresponding curve of pulse JDL method is still very steady and higher, illustrates that the clutter recognition performance of the method for the present invention is very outstanding.This
It is mainly based upon false impulse of the invention to filter and unconventional fixed weight coefficient filtering, therefore, using the method for the present invention
Clutter recognition effect significantly reduces the susceptibility of array error compared to conventional method, i.e. the method for the present invention is there are larger battle arrays
There is better range ambiguity clutter recognition effect in the case where first error.
Those of ordinary skill in the art will appreciate that: realize that all or part of the steps of above method embodiment can pass through
The relevant hardware of program instruction is completed, and program above-mentioned can be stored in a computer readable storage medium, the program
When being executed, step including the steps of the foregoing method embodiments is executed；And storage medium above-mentioned includes: ROM, RAM, magnetic disk or light
The various media that can store program code such as disk.
The above description is merely a specific embodiment, but scope of protection of the present invention is not limited thereto, any
Those familiar with the art in the technical scope disclosed by the present invention, can easily think of the change or the replacement, and should all contain
Lid is within protection scope of the present invention.Therefore, protection scope of the present invention should be based on the protection scope of the described claims.
Claims (8)
1. the range ambiguity clutter suppression method based on false impulse, which comprises the following steps:
Step 1, setting FDA-MIMO radar has M transmitting array element and N number of reception array element, and persistently samples in K pulse,
Obtain M × N × K dimension practical steering vector a (λ of send-receive-Doppler0, rL, p, ΨL, p, q, vL, p, q)；
Wherein, λ0For carrier wavelength, l indicates first of range gate, and p indicates pth range ambiguity region, and q indicates q-th of scattering point,
rL, pIndicate the distance of first of range gate on pth range ambiguity region, ψL, p, qIndicate first of distance on pth range ambiguity region
The airspace cone angle of q-th of scattering point on door, vL, p, qIndicate q-th of scattering on pth range ambiguity region in first of range gate
Radial velocity of the movement velocity of point with respect to radar；
Step 2, according to the practical steering vector a (λ of send-receive-Doppler0, rL, p, ψL, p, vL, p, q), obtain FDA-MIMO radar
NpA range ambiguity region clutter data C；
NpThe l of a range ambiguity region clutter data C is classified as cl, clFor the clutter data of first of range gate,
Wherein, CNR is the clutter noise power ratio being arranged when emulation, NpIndicate the sum in range ambiguity region, NcIndicate it is corresponding away from
Clutter scattering unit sum from fuzzy region；nlFor the noise introduced when being sampled to first of range gate, point of the noise
Cloth form is M × N × K dimension white Gaussian noise, power 1；ξL, p, qIndicate first on p-th of range ambiguity region away from
Scattering coefficient from q-th of clutter scattering unit on door, scattering coefficient ξL, p, qObeying mean value is 0, the Gauss point that variance is 1
Cloth；
Step 3, FDA-MIMO radar emission false impulse, since second false impulse repetition period, to false impulse
Echo carries out sampling and matched filtering, obtains the clutter data C of removal first distance fuzzy region- 1, n, n=2 ..., Np；
Remove the clutter data C of first distance fuzzy region- 1, nL be classified as c- 1, n, l, c- 1, n, lIt is the echo of first of range gate
Data,
Wherein, a ' (λ ', rL, p, ψL, n, q) be false impulse steering vector, λ ' be the carrier wavelength answered of auxiliary pulse pair；
Step 4, by NpThe clutter data C of a range ambiguity region clutter data C and removal first distance fuzzy region- 1, nRespectively
Transmitting domain frequency distance dependence compensation is carried out for first distance fuzzy region, obtains compensated NpA range ambiguity region
Clutter data CcWith the clutter data C of compensated removal first distance fuzzy regionc - 1, n；
Step 5, target detection position is chosen, according to the space cone angle cosine value cos ψ at target detection positiont, emitted-connect
Receive domain transformation matrix Ts；
Wherein,Indicate Kronecker product；ψtFor the space cone angle at target detection position, ψ1With ψ2For selected by accessory channel
Space cone angle, atc(λ0, Ψt) indicate target inspection
Location sets the process at place apart from the compensated transmitting domain steering vector of dependent Frequency, atc(λ0, ψ1) representation space cone angle ψ1The warp at place
It crosses apart from the compensated transmitting domain steering vector of dependent Frequency, atc(λ0, ψ2) representation space cone angle ψ2Place relies on frequency by distance
The compensated transmitting domain steering vector of rate, ar(λ0, ψt) indicate target detection position at reception domain steering vector, ar(λ0, ψ1)
Representation space cone angle ψ1The reception domain steering vector at place, ar(λ0, ψ2) representation space cone angle ψ2The reception domain steering vector at place；
Step 6, using the clutter data C of compensated removal first distance fuzzy region- 1, nCarry out the association side in send-receive domain
Poor Matrix Estimation, the covariance matrix in the send-receive domain estimated
Wherein, ()HThe conjugate transposition of representing matrix, L are Matrix C- 1, nColumns and range gate number,For noise
Power, IMNFor the unit matrix of M × N row M × N column；
Step 7, using the covariance matrix in the send-receive domain of estimationTo send-receive domain transformation matrix TsIt is filtered
Processing, obtains dimensionality reduction matrix Tsd；
Step 8, according to compensated NpA range ambiguity region clutter data Cc, using dimensionality reduction matrix TsdApart from certainly when carrying out empty
Adaptation processing, obtains weight vector w:
Wherein, vtFor the relative radial rate between target to be detected and radar, α is constant；It is filtered using weight vector w
Wave processing.
2. the range ambiguity clutter suppression method according to claim 1 based on false impulse, which is characterized in that step 1
Include following sub-step:
Sub-step 1a obtains ideal transmitting domain steering vector:
Wherein, j is imaginary unit, ft(λ0, rL, p, ψL, p, q) indicate the transmitting domain frequency that distance relies on, ft(λ0, rL, p, ψL, p, q)
=-2 Δ frL, p/c+dtcos(ψL, p, q)/λ0, c is the light velocity, and Δ f is the interval of FDA-MIMO radar emission carrier frequency, dtFor equal space line
Emit the location interval between array element, f in battle array0For reference array element carrier frequency, ()TThe transposition of representing matrix.
Emit domain steering vector according to ideal, obtain removing the ideal transmitting domain steering vector after dependent Frequency are as follows:
Wherein, ftc(λ0, ψL, p, q) indicate transmitting domain frequency of the removal after dependent Frequency, ftc(λ0, ψL, p, q)=dtcos
(ψL, p, q)/λ0, ()TThe transposition of representing matrix.
Sub-step 1b obtains ideal reception domain steering vector:
Wherein, fr(λ0, ψL, p, q) indicate to receive domain frequency, fr(λ0, ψL, p, q)=drcos(ψL, p, q)/λ0。
Sub-step 1c obtains ideal Doppler domain steering vector:
Wherein, fd(ΨL, p, q, vL, p, q) indicate Doppler domain frequency, fd(ψL, p, q, vL, p, q(the v of)=2L, p, q+vR)Tcos(ψL, p, q),
vL, p, qSpeed, v are moved radially for the corresponding opposite radar of corresponding scattering unitRFor the movement velocity of radar, T is pulse repetition
Period.
Sub-step 1d receives domain steering vector and ideal Doppler domain steering vector according to ideal transmitting domain steering vector, ideal,
It obtains M × N × K and ties up ideal steering vector:
Sub-step 1e ties up ideal steering vector to M × N × K and carries out array element error introducing processing, obtains practical steering vector:
a(λ0, rL, p, ψL, p, q, vL, p, q)=D*ai(λ0, rL, p, ψL, p, q, vL, p, q),
Wherein, D indicates array element error matrix,
Diag { } operator is to be placed on column vector in order on the main diagonal element of matrix, remaining 0 composition square matrix of supplement；Δ
aT, mIndicate the range error constant of m-th of transmitting array element, m=1,2 ... M, Δ aR, nIndicate that the amplitude of n-th of reception array element is missed
Poor constant, n=1,2 ... N, Δ aT, mWith Δ aR, nObeying mean value is 0, and standard deviation is the Gaussian Profile of margin of error X,
Emit the phase error constant of array element for m-th,The phase error constant of array element is received for n-th,KnowObeying mean value is 0, and coefficient is uniformly distributed for Y's, 1KIndicate complete 1 K dimension column vector.
3. the range ambiguity clutter suppression method according to claim 1 based on false impulse, which is characterized in that step 3
In, the false impulse uses orthogonal frequency division multiplexing method, before making each emit in the false impulse and step 1 that array element is sent out
K normal burst difference is orthogonal and mutually orthogonal between each false impulse.
4. the range ambiguity clutter suppression method according to claim 3 based on false impulse, which is characterized in that step 3
In, each frequency shift amount Δ f ' for emitting the corresponding false impulse of array element meets the following conditions:
Δf′≥B+(M-1)Δf+BD,
Wherein, B is the bandwidth of preceding K normal burst, BDFor the doppler bandwidth of preceding K normal burst.
5. the range ambiguity clutter suppression method according to claim 1 based on false impulse, which is characterized in that step 3
In,
Wherein, at(λ ', rL, p, ψL, n, q) indicate false impulse transmitting domain steering vector, ar(λ ', ψL, n, q) indicate false impulse
Reception domain steering vector.
6. the range ambiguity clutter suppression method according to claim 2 based on false impulse, which is characterized in that step 4
Include following sub-step:
Sub-step 4a, construction compensation column vector gt(rL, 1):
Wherein, rL, 1The oblique distance of expression first of range gate of first distance fuzzy region, 1NIndicate complete 1 column vector of N-dimensional.
Sub-step 4b, using compensation column vector to NpA range ambiguity region clutter data C is compensated, and obtains compensated Np
A range ambiguity region clutter data Cc:
Compensated NpA range ambiguity region clutter data CcL be classified as cl c,
cl c=diag { gt(rL, 1)}cl,
Sub-step 4c, using compensation column vector to the clutter data C of removal first distance fuzzy region- 1, nIt compensates, is mended
The clutter data C of removal first distance fuzzy region after repaying- 1, n；
The clutter data C of compensated removal first distance fuzzy region- 1, nL be classified as cc - 1, n, l,
cc - 1, n, l=diag { gts(rL, 1)}c- 1, n, l。
7. the range ambiguity clutter suppression method according to claim 6 based on false impulse, which is characterized in that sub-step
In 4b and sub-step 4c, when compensating, oblique distance rL, 1With the clutter data C of removal first distance fuzzy region- 1, nIn column
Match, i.e., in rL, 1In l and cc - 1, n, lIn the identical situation of l under, compensate.
8. the range ambiguity clutter suppression method according to claim 1 based on false impulse, which is characterized in that step 7
Include following sub-step:
Sub-step 7a, using the covariance matrix in the send-receive domain of estimationTo send-receive domain transformation matrix TsIt carries out
Filtering, obtains filtered send-receive domain transformation matrix T 's:
Wherein, ()-1For matrix inversion operation；
Sub-step 7b, according to filtered send-receive domain transformation matrix T 's, obtain dimensionality reduction matrix Tsd:
Wherein, ad(ψt, vt) indicate Doppler domain steering vector at target velocity, ad(ψt, v1) indicate accessory channel speed v1Locate more
General Le domain steering vector, ad(ψt, v2) indicate accessory channel speed v2Locate Doppler domain steering vector, v1With v2For accessory channel institute
The speed of selection,
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910097128.7A CN109814070B (en) | 2019-01-31 | 2019-01-31 | Distance fuzzy clutter suppression method based on auxiliary pulse |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910097128.7A CN109814070B (en) | 2019-01-31 | 2019-01-31 | Distance fuzzy clutter suppression method based on auxiliary pulse |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109814070A true CN109814070A (en) | 2019-05-28 |
| CN109814070B CN109814070B (en) | 2022-11-18 |
Family
ID=66606165
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910097128.7A Active CN109814070B (en) | 2019-01-31 | 2019-01-31 | Distance fuzzy clutter suppression method based on auxiliary pulse |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109814070B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110376560A (en) * | 2019-06-03 | 2019-10-25 | 西安电子科技大学 | A kind of airborne bistatic MIMO radar amplitude and phase error correction method based on single range gate |
| CN110865344A (en) * | 2019-11-22 | 2020-03-06 | 北京理工大学 | Rapid side lobe suppression method under pulse Doppler radar system |
| CN112782663A (en) * | 2021-02-03 | 2021-05-11 | 海南大学 | Target parameter estimation method of FDA-MIMO radar under amplitude-phase error condition |
| CN114265018A (en) * | 2022-02-28 | 2022-04-01 | 西安电子科技大学 | Short-range clutter suppression method based on multi-frequency split radar |
| CN115047425A (en) * | 2022-05-25 | 2022-09-13 | 西安电子科技大学 | Method and device for quickly simulating clutter of ultra-high-speed platform |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2478816A1 (en) * | 2002-03-13 | 2003-09-25 | Raytheon Canada Limited | System and method for spectral generation in radar |
| CN106569212A (en) * | 2016-11-09 | 2017-04-19 | 西安空间无线电技术研究所 | Multichannel SAR-GMTI range ambiguity clutter suppression method |
| CN107703490A (en) * | 2017-09-29 | 2018-02-16 | 西安电子科技大学 | Range ambiguity clutter suppression method based on FDA MIMO radars |
-
2019
- 2019-01-31 CN CN201910097128.7A patent/CN109814070B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2478816A1 (en) * | 2002-03-13 | 2003-09-25 | Raytheon Canada Limited | System and method for spectral generation in radar |
| CN106569212A (en) * | 2016-11-09 | 2017-04-19 | 西安空间无线电技术研究所 | Multichannel SAR-GMTI range ambiguity clutter suppression method |
| CN107703490A (en) * | 2017-09-29 | 2018-02-16 | 西安电子科技大学 | Range ambiguity clutter suppression method based on FDA MIMO radars |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110376560A (en) * | 2019-06-03 | 2019-10-25 | 西安电子科技大学 | A kind of airborne bistatic MIMO radar amplitude and phase error correction method based on single range gate |
| CN110376560B (en) * | 2019-06-03 | 2021-05-07 | 西安电子科技大学 | Airborne bistatic MIMO radar amplitude-phase error correction method based on single range gate |
| CN110865344A (en) * | 2019-11-22 | 2020-03-06 | 北京理工大学 | Rapid side lobe suppression method under pulse Doppler radar system |
| CN112782663A (en) * | 2021-02-03 | 2021-05-11 | 海南大学 | Target parameter estimation method of FDA-MIMO radar under amplitude-phase error condition |
| CN112782663B (en) * | 2021-02-03 | 2023-07-21 | 海南大学 | Target parameter estimation method of FDA-MIMO radar under amplitude-phase error condition |
| CN114265018A (en) * | 2022-02-28 | 2022-04-01 | 西安电子科技大学 | Short-range clutter suppression method based on multi-frequency split radar |
| CN114265018B (en) * | 2022-02-28 | 2022-05-31 | 西安电子科技大学 | Short-range clutter suppression method based on multi-frequency split radar |
| CN115047425A (en) * | 2022-05-25 | 2022-09-13 | 西安电子科技大学 | Method and device for quickly simulating clutter of ultra-high-speed platform |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109814070B (en) | 2022-11-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109814070A (en) | Range ambiguity clutter suppression method based on false impulse | |
| CN111880171B (en) | Pulse segment coding method for eliminating radar target blind speed | |
| Zhang et al. | A method for finding best channels in beam-space post-Doppler reduced-dimension STAP | |
| CN105738879B (en) | Radar clutter space-time adaptive pre-filtering method based on sparse recovery | |
| CN104977571B (en) | Range ambiguity clutter suppression method based on pitching frequency diversity STAP | |
| CN107607938B (en) | Frequency diversity array radar low-altitude target detection method | |
| CN103728606A (en) | Doppler channel correlation two-stage dimension reduction method for onboard multiple input multiple output (MIMO) radar | |
| CN109375179A (en) | A kind of strong clutter suppression method of airborne radar short range based on rarefaction representation | |
| Wen et al. | Bistatic FDA-MIMO radar space-time adaptive processing | |
| CN103942449A (en) | Feature interference cancellation beam forming method based on estimation of number of information sources | |
| CN106772304A (en) | Doppler's adaptive processing method after airborne MIMO radar based on spatial domain multi-level decomposition | |
| CN110412533A (en) | Clutter suppression method based on three-dimensional perspective Doppler effect correction | |
| CN109738856A (en) | A kind of noise suppressed Capon active target DOA evaluation method based on time reversal | |
| CN101807977A (en) | Space-time blind self-adapting anti-jamming method based on waveform characteristics | |
| CN108710103A (en) | Strong and weak multiple target super-resolution direction finding based on thinned array and Sources number estimation method | |
| CN110471033A (en) | Two-dimentional Space Time Coding disturbance restraining method based on relevant FDA | |
| CN110082744A (en) | The MIMO airborne bistatic radar clutter suppression method of Doppler's stepped multiplexing | |
| CN105785330A (en) | Cognitive minor lobe interference suppression method | |
| CN101907702A (en) | Two-dimensional multi-pulse canceller for MIMO radar | |
| CN110632573A (en) | Airborne broadband radar space-time two-dimensional keystone transformation method | |
| CN104345299A (en) | Airborne MIMO (Multiple Input Multiple Output) radar space-time self-adaptive processing method based on simplified EC | |
| CN106019243A (en) | Inter-pulse initial phase third-power modulation and FRFT (fractional Fourier transform)-based DRFM (digital radio frequency memory) interference detection and resisting method | |
| CN101726730A (en) | Self-adaption anti-coherent interference technology based on characteristic component rejection | |
| CN106125039B (en) | Improvement space-time adaptive Monopulse estimation method based on local Combined Treatment | |
| CN113376607B (en) | Airborne distributed radar small sample space-time self-adaptive processing method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |