CN108710102A - Wave arrival direction estimating method based on relatively prime array second order equivalence virtual signal inverse discrete Fourier transform - Google Patents

Wave arrival direction estimating method based on relatively prime array second order equivalence virtual signal inverse discrete Fourier transform Download PDF

Info

Publication number
CN108710102A
CN108710102A CN201810460228.7A CN201810460228A CN108710102A CN 108710102 A CN108710102 A CN 108710102A CN 201810460228 A CN201810460228 A CN 201810460228A CN 108710102 A CN108710102 A CN 108710102A
Authority
CN
China
Prior art keywords
signal
array
virtual
relatively prime
angle
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
Application number
CN201810460228.7A
Other languages
Chinese (zh)
Other versions
CN108710102B (en
Inventor
张宗煜
史治国
周成伟
陈积明
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhejiang University ZJU
Original Assignee
Zhejiang University ZJU
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Zhejiang University ZJU filed Critical Zhejiang University ZJU
Priority to CN201810460228.7A priority Critical patent/CN108710102B/en
Publication of CN108710102A publication Critical patent/CN108710102A/en
Application granted granted Critical
Publication of CN108710102B publication Critical patent/CN108710102B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S3/00Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received
    • G01S3/02Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received using radio waves
    • G01S3/14Systems for determining direction or deviation from predetermined direction
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S3/00Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received
    • G01S3/78Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received using electromagnetic waves other than radio waves
    • G01S3/782Systems for determining direction or deviation from predetermined direction
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S3/00Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received
    • G01S3/80Direction-finders for determining the direction from which infrasonic, sonic, ultrasonic, or electromagnetic waves, or particle emission, not having a directional significance, are being received using ultrasonic, sonic or infrasonic waves
    • G01S3/802Systems for determining direction or deviation from predetermined direction
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F17/00Digital computing or data processing equipment or methods, specially adapted for specific functions
    • G06F17/10Complex mathematical operations
    • G06F17/14Fourier, Walsh or analogous domain transformations, e.g. Laplace, Hilbert, Karhunen-Loeve, transforms
    • G06F17/141Discrete Fourier transforms
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F17/00Digital computing or data processing equipment or methods, specially adapted for specific functions
    • G06F17/10Complex mathematical operations
    • G06F17/16Matrix or vector computation, e.g. matrix-matrix or matrix-vector multiplication, matrix factorization

Abstract

The invention discloses a kind of Wave arrival direction estimating method based on relatively prime array second order equivalence virtual signal inverse discrete Fourier transform, mainly solves the problems, such as that existing method computation complexity is higher and can not estimate simultaneously with signal power.Implementation step is:The relatively prime array of receiving terminal framework;Using relatively prime array received incoming signal and model;The second order equivalence virtual signal corresponding to the virtual uniform linear array of augmentation is derived according to relatively prime array received signal;It defines angle-spatial frequency and describes the second order equivalence virtual signal of virtual uniform linear array with it;Inverse discrete Fourier transform is carried out to the second order equivalence virtual signal using angle-spatial frequency description, builds space power spectrum;The Mutual coupling and power estimated information that spectrum peak search obtains signal are carried out according to constructed space power spectrum.The present invention reduces the computation complexity of Mutual coupling, and can obtain the power estimated information of signal simultaneously while improving Mutual coupling degree of freedom performance.

Description

Wave based on relatively prime array second order equivalence virtual signal inverse discrete Fourier transform reaches side To method of estimation
Technical field
The invention belongs to signal processing technology fields, more particularly to the system of radar signal, acoustic signal and electromagnetic signal Signal processing is counted, specifically a kind of direction of arrival based on relatively prime array second order equivalence virtual signal inverse discrete Fourier transform is estimated Meter method, can be used for passive location and target acquisition.
Background technology
Direction of arrival (Direction-of-Arrival, DOA) estimation is that one of array signal processing field asks substantially Topic, it refers to receiving signal using sensor array, and carry out Statistics Division by the docking collection of letters number of a series of signal processing method Reason, to obtain direction of arrival information included in signal, has extensively in fields such as radar, sonar, voice, wireless communications General application.
The degree of freedom of DOA estimation method refers to the incident signal source number that it can estimate.Traditional DOA estimation method is logical The reception and modeling of signal, but the freedom of the DOA estimation method based on uniform linear array are carried out frequently with uniform linear array Degree is limited to physics element number of array.When incident signal source number is more than physics element number of array in array, it is based on homogenous linear The DOA estimation method of array will be unable to obtain effective estimated result.Relatively prime array is a kind of non-equal with systematization structure Even thinned array can break through the limitation of conventional uniform linear array degree of freedom, realize in the case where physics array number is certain The promotion of degree of freedom performance, therefore the extensive concern of academia is obtained in recent years.The original of DOA estimation method based on relatively prime array Reason is built one and corresponds to the two of virtual uniform linear array to be derived relatively prime array to virtual Domain using the property of prime number Rank equivalence virtual signal is estimated for DOA.Virtual array quantity is more than physics array element quantity in the virtual uniform linear array, because This realizes the promotion of degree of freedom.
The existing DOA estimation method based on relatively prime array mostly on the basis of relatively prime array second order equivalence virtual signal into The more complicated operation of row, including invert, the design of complicated matrix operation and convex optimization problem such as Eigenvalues Decomposition with ask Processes, these calculating processes such as solution result in higher computation complexity, are faced under the higher application scenarios of requirement of real-time Certain challenge, and hardware realization in systems in practice is more difficult.In addition, existing DOA estimation method mostly can not be The power information of signal is obtained while obtaining Mutual coupling information.However, signal power is also describe signal one Important Parameters, the detection for target and identification important in inhibiting.
Invention content
It is a kind of based on relatively prime array second order etc. it is an object of the invention in view of the deficiency of the prior art, propose The Wave arrival direction estimating method of valence virtual signal inverse discrete Fourier transform, by using the mutual of angle-spatial frequency description Matter array second order equivalence virtual signal carries out inverse discrete Fourier transform, realizes that DOA estimates degree of freedom performance boost, and obtain simultaneously The Mutual coupling for the number of winning the confidence and corresponding signal power information.Institute's extracting method of the present invention has lower computation complexity, It is easy to hardware realization in systems in practice.
The purpose of the present invention is achieved through the following technical solutions:One kind is based on relatively prime array second order virtual letter of equal value The Wave arrival direction estimating method of number inverse discrete Fourier transform, comprises the steps of:
(1) receiving terminal uses 2M+N-1 array element, and carries out framework according to relatively prime array structure;Wherein M and N is relatively prime whole Number;
(2) assume there are L to come from θ=s [θ12,…,θL]TThe far field narrowband incoherent signal source , &#91 in direction;·]TIt indicates to turn Operation is set, incoming signal is received using the relatively prime array built in step (1), then in the relatively prime array received of t moment Signal x (t) can be modeled as:
Wherein, x (t) is (2M+N-1) × 1 dimensional vector, sl(t) be first of incoming signal waveform, n (t) be and each letter Number mutually independent noise component(s) in source, a (θl) it is corresponding to θlThe relatively prime array steering vector in direction signal source, is represented by
Wherein, μi, i=1,2,3 ..., 2M+N-1 indicate the physical location of i-th of physics array element in relatively prime array, and head The position of a physics array element is μ1=0, λ are the wavelength of incident narrow band signal, and j is imaginary unit.
Covariance matrix is built according to relatively prime array received signal x (t):The sampling association side obtained using T sampling snap Poor matrixTo theoretical covariance matrix RxCarry out approximate substitution;
(3) the second order virtual letter of equal value corresponding to the virtual uniform linear array of augmentation is derived according to relatively prime array received signal Number:Pass through vectorization sample covariance matrixObtain virtual array equivalence virtual signal y:
Wherein,For (2M+N-1)2× L ties up guiding matrix,To include the vector of L incoming signal source power, For noise power, i=vec (I2M+N-1), I2M+N-1Indicate (2M+N-1 × (2M+N-1 ties up unit matrix, and vec () indicates vector Change operation, i.e., each row in matrix is stacked gradually to form a new vector, ()*Indicate conjugate operation,Expression gram Kronecker product;
The corresponding non-homogeneous virtual array S of vectorial yDIt is expressed as:
SD={ ± (Mn-Nm) d, 0≤n≤N-1,0≤m≤2M-1 },
Wherein d is the half of incident narrow band signal wavelength, i.e.,
Choose non-homogeneous virtual array SDThe Virtual array of middle maximum continuous part, composition one include 2V+1 virtual array The virtual uniform linear array S of memberV={-Vd ,-(V-1) d ..., 0 ..., (V-1) d, Vd }, V=MN+M-1;
Selection corresponds to S from vectorial yVIn each Virtual array position virtual signal of equal value, form virtual uniform linear array Corresponding second order equivalence virtual signal zθ, it is represented by:
Wherein, B (θ)=s [b(θ1),b(θ2),…b(θL)], l row
It is right It should be in θlThe virtual uniform linear array steering vector in direction signal source, e are by selecting to correspond to S from iVThe element of middle array element forms Vector;
(4) it defines angle-spatial frequency and describes the second order equivalence virtual signal of virtual uniform linear array with it.Define angle Degree-spatial frequency is propagated by the narrow band signal from direction θ in space within the scope of propagation distance difference between adjacent array element Signal period number.The second order equivalence virtual signal z of virtual uniform linear array in step (3)θIt can be of equal value in angle-spatial frequency domain It is expressed as:
Wherein, B (ξ)=s [b(ξ1),b(ξ2),…b(ξL)], l row ξ=s [ξ12,…,ξL]TIt is right Angle-spatial frequency of L angle included in θ;
(5) inverse discrete Fourier transform, and structure are carried out to the second order equivalence virtual signal using angle-spatial frequency description Build space power spectrum:The second order equivalence virtual signal z that will be indicated by angle-spatial frequency by inverse discrete Fourier transformξ Conversion obtains the dimension spaces of its K × 1 response ψ to spatial domain;
A space power spectrum is built, the horizontal axis of the spectrum indicates angle, θ, the pass with vectorial k-th of the element of roomage response System is represented by:
Wherein, k=0,1 ..., K-1, arccos () are inverse cosine function, and h is to ensureMeet anticosine letter The coefficient of several domains, whenWhen, h=-1, whenWhen, h=0;The longitudinal axis representation space of the spectrum The mould P (k) of k-th of element in response vector;
(6) Mutual coupling is carried out according to gained space power spectrum and signal power is estimated.To space work(in step (5) Rate spectrum carries out spectrum peak search operation, then the corresponding angle of the maximum preceding L peak value of amplitude is the direction of arrival of L incoming signal Estimation, and its peak amplitude is the power estimation value to induction signal.
Further, the relatively prime array structure described in step (1) can be specifically described as:First, choose one group it is relatively prime whole Number M, N, a pair of sparse homogenous linear subarray of construction.First subarray includes the array element that 2M spacing is Nd, and position is 0,Nd,…,(2M-1)Nd;Second subarray includes the array element that N number of spacing is Md, position 0, Md ..., (N-1) Md.It Two subarrays are combined in such a way that first array element overlaps afterwards, are obtained non-homogeneous comprising 2M+N-1 physics array element Relatively prime array.
Further, in step (3), if there are multiple and different elements and S in yVIn same Virtual array position it is corresponding Situation then selects any one in these elements as composition of vector zθElement.
Further, angle-spatial frequency in step (4) is a kind of frequency related with signal incident angle, specifically It defines in the following way:The narrow band signal arrival intervals from direction θ are that the adjacent array element of d will produce one section in space Propagation distance difference u, is represented by:
U=dcos θ.
Fixed in array element spacing, propagation distance difference u only changes with incoming signal angle, θ, therefore obtains The definition of angle-spatial frequency in step (4).Angle-spatial frequency ξ and the relationship of incoming signal angle, θ are represented by:
Further, the second order equivalence virtual signal z obtained by inverse discrete Fourier transform in the step (5)ξK × 1 dimension space responds ψ, is represented by:
Wherein,Indicate inverse discrete Fourier transform operation, FKIt, can table for leaf inverse-transform matrix in K point discrete Fouriers It is shown as:
The roomage response ψ of gained is the dimensional vectors of K × 1.
Further, in the step (5), constructed spatial spectrum reflects the response amplitude in each angle in space, Wherein there is the L peak value corresponding to L incoming signal.
Further, there is the L peak value corresponding to L incoming signal, the knot in the step (5) in space power spectrum By obtaining in the following way:Relationship P (k) for building space power spectrum is specifically represented by:
Wherein,For the power of first of signal, δ () indicates impulse function, is integer, for indicating the impulse function For periodical impulse string sequence.According to the property of impulse function it is found that only when When, P (k) is peak Value.Since L incoming signal has different angle-spatial frequencys, each angle-spatial frequency energy and it is only capable of in spatial power Cause a peak value in spectrum, therefore there is the L peak value corresponding to L incoming signal in space power spectrum.
Compared with the prior art, the present invention has the following advantages:
(1) institute's extracting method of the present invention to the relatively prime array second order equivalence virtual signal using the description of angle-spatial frequency into The mode of row inverse discrete Fourier transform obtains roomage response and based on this structure space power spectrum, by constructed space work( The spectrum peak search process of rate spectrum obtains Mutual coupling as a result, avoiding common convex excellent in traditional Wave arrival direction estimating method The design of change problem solves and the complicated calculations processes such as matrix inversion, Eigenvalue Decomposition, is ensureing DOA estimation degree of freedom On the basis of capable of being promoted, the power estimation of signal can be obtained simultaneously.
(2) institute's extracting method of the present invention carries out Mutual coupling using inverse discrete Fourier transform, significantly reduces meter Complexity is calculated, preferably meets the higher application demand of requirement of real-time, while being easy to hardware realization in systems in practice.
Description of the drawings
Fig. 1 is the method overall procedure block diagram of the present invention;
Fig. 2 is the sparse uniform subarray structural schematic diagram of a pair that relatively prime array is formed in the present invention;
Fig. 3 is the structural schematic diagram of relatively prime array in the present invention;
Fig. 4 is the schematic diagram for embodying institute's extracting method signal power accuracy of estimation under different signal-to-noise ratio of the present invention;
Fig. 5 is the signal for embodying institute's extracting method of the present invention signal power accuracy of estimation under different sampling number of snapshots Figure;
Fig. 6 is the space power spectrum schematic diagram for embodying institute's extracting method degree of freedom performance of the present invention.
Specific implementation mode
Referring to the drawings, technical solutions and effects of the present invention is described in further detail.
Relatively prime array is realized due to that can carry out statistical disposition to its second order equivalence virtual array signal in physics array number The promotion of degree of freedom performance, obtains the extensive concern of academia in recent years in the case of certain.It is existing in real system application DOA estimation method computation complexity it is higher, it is difficult to meet the higher application scenarios of requirement of real-time, and complicated calculating process There are certain difficulties for hardware realization in systems in practice.In addition, existing DOA estimation method can not obtain wave up to side mostly To the power for estimating each signal source while estimation.In view of the above problems, the present invention provides one kind being based on relatively prime array second order The Wave arrival direction estimating method of virtual signal inverse discrete Fourier transform of equal value, referring to Fig.1, steps are as follows for realization of the invention:
Step 1:In receiving terminal relatively prime array is built using 2M+N-1 practical array element.First, choose one group it is relatively prime whole Number M, N, a pair of sparse homogenous linear subarray of construction.First subarray includes the array element that 2M spacing is Nd, and position is 0,Nd,…,(2M-1)Nd;Second subarray includes the array element that N number of spacing is Md, position 0, Md ..., (N-1) Md, Middle unit spacing d is half-wavelength, that is, λ/2 d=of incident narrow band signal.Two subarrays are overlapped according to first array element later Mode is combined, and obtains the non-homogeneous relatively prime array for including 2M+N-1 practical array element.
Step 2:Using relatively prime array received signal and to signal modeling.Assuming that there is L to come from θ=s [θ12,…,θL]T The far field narrowband incoherent signal source , &#91 in direction;·]TTransposition operation is indicated, using the relatively prime array built in step 1 to incidence Signal is received, then can be modeled as in the relatively prime array received signal x (t) of t moment:
Wherein, x (t) is (2M+N-1) × 1 dimensional vector, sl(t) be first of incoming signal waveform, n (t) be and each letter Number mutually independent noise component(s) in source, a (θl) it is corresponding to θlThe relatively prime array steering vector in direction signal source, is represented by
Wherein, μi, i=1,2,3,2M+N-1 indicates the physical location of i-th of physics array element in relatively prime array, and first The position of physics array element is μ1=0, λ are the wavelength of incident narrow band signal, and j is imaginary unit.In practice, fast using T sampling Clap obtained sample covariance matrixTo theoretical covariance matrix RxApproximate substitution is carried out,And RxIt can be expressed as
Rx=E[x(t)xH(t)],
Wherein, ()HIndicate conjugate transposition, E[·]Indicate mathematic expectaion.
Step 3:The second order void of equal value corresponding to the virtual uniform linear array of augmentation is derived according to relatively prime array received signal Quasi- signal.Virtual array equivalence virtual signal y can pass through the sample covariance matrix in vectorization step 2It obtains:
Wherein,For (2M+N-1)2× L ties up guiding matrix,To include the vector of L incoming signal source power, For noise power, i=vec (I2M+N-1), I2M+N-1Indicate (2M+N-1) × (2M+N-1) tie up unit matrix, vec () indicate to Quantization operation is stacked gradually each row in matrix to form a new vector, ()*Indicate conjugate operation,It indicates Kronecker product.The corresponding non-homogeneous virtual array S of vectorial yDIt is represented by:
SD={ ± (Mn-Nm) d, 0≤n≤N-1,0≤m≤2M-1 },
Wherein d is the half of incident narrow band signal wavelength, i.e.,Choose non-homogeneous virtual array SDIt is middle maximum continuous Partial Virtual array forms a virtual uniform linear array S for including 2V+1 Virtual arrayV=-Vd ,-(V-1) d ..., 0 ..., (V-1) d, Vd }, wherein V=MN+M-1.Selection corresponds to S from vectorial yVIn each Virtual array position equivalence it is virtual Signal, the corresponding second order equivalence virtual signal z of composition virtual uniform linear arrayθ, it is represented by:
Wherein, B (θ)=s [b(θ1),b(θ2),…b(θL)], l rowIt is right It should be in θlThe virtual uniform linear array steering vector in direction signal source, e are by selecting to correspond to S from iVThe element composition of array element Vector.If there are multiple and different elements and S in yVIn situation corresponding to same Virtual array position, then select in these elements Any one is as composition of vector zθElement.
Step 4:It defines angle-spatial frequency and describes the second order equivalence virtual signal of virtual uniform linear array with it.Definition Angle-spatial frequency is propagated by the narrow band signal from direction θ in space within the scope of propagation distance difference between adjacent array element Signal period number.Specifically, the narrow band signal arrival intervals from direction θ are that the adjacent array element of d will produce one section in space Propagation distance is poor, is represented by:
U=dcos θ,
In the case where array element spacing is certain, which changes with incident angle θ, and angle-spatial frequency is fixed Justice is the periodicity that narrow band signal is propagated in the propagation distance difference, i.e.,:
Correspondingly, in step 3 virtual uniform linear array second order equivalence virtual signal zθIt can be in angle-spatial frequency domain It is expressed equivalently as:
Wherein ξ=s [ξ12,…,ξL]TCorresponding to angle-spatial frequency of L angle included in θ.
Step 5:Inverse discrete Fourier transform is carried out to the second order equivalence virtual signal using angle-spatial frequency description, Obtain roomage response.It can be by the second order indicated by angle-spatial frequency virtual letter of equal value by inverse discrete Fourier transform Number zξConversion obtains its roomage response ψ to spatial domain, is represented by:
Wherein,Indicate inverse discrete Fourier transform operation, FKIt, can table for leaf inverse-transform matrix in K point discrete Fouriers It is shown as:
The roomage response ψ of gained is the dimensional vectors of K × 1.A space power spectrum is built, the horizontal axis of the spectrum indicates angle, θ, It is represented by with the relationship of vectorial k-th of the element of roomage response:
Wherein, k=0,1 ..., K-1, arccos () are inverse cosine function, and h is to ensureMeet anticosine letter The coefficient of several domains, whenWhen, h=-1, whenWhen, h=0;The spectrum The mould P (k) of k-th of element, is represented by longitudinal axis representation space response vector:
P (k)=s |[ψ]k|,
Wherein , [·]kIndicate k-th of element , &#124 in vector;·|Indicate the mould of plural number.Specifically, P (k) is represented by:
Wherein,For the power of first of signal, δ () indicates impulse function, is integer, for indicating the impulse function For periodical impulse string sequence.According to the property of impulse function it is found that only whenWhen, P (k) is peak Value.Since L incoming signal has different angle-spatial frequencys, each angle-spatial frequency energy and it is only capable of in spatial power Cause a peak value in spectrum, therefore there is the L peak value corresponding to L incoming signal in space power spectrum.
Step 6:Mutual coupling and signal power estimation are carried out according to gained space power spectrum.It is hollow to step 5 Between power spectrum carry out spectrum peak search operation, by its peak value according to arranging from high to low, then it is a to correspond to L for maximum preceding L peak value Incoming signal, while the peak value of this L spectral peak is respectively the power estimation value of corresponding signal.
The carried Wave arrival direction estimating method of the present invention passes through to the relatively prime array second order etc. using angle-spatial frequency description Valence virtual signal carries out inverse discrete Fourier transform and obtains roomage response and build a space power spectrum based on this, by this The spectrum peak search process of space power spectrum can obtain the power estimation letter of Mutual coupling information and corresponding signal simultaneously Breath.Compared to traditional Wave arrival direction estimating method based on uniform linear array, institute's extracting method of the present invention ensure that wave reaches While direction estimation degree of freedom performance boost, computation complexity is onlyPreferably meet to real-time have it is higher It is required that practical application scene, be also easier to hardware realization in systems in practice.
The effect of the present invention is further described with reference to simulation example.
Simulation example 1:Using relatively prime array received incoming signal, parameter is chosen for M=9, N=10, i.e., framework is mutual Matter array includes 2M+N-1=27 physics array element altogether.Fixed sample number of snapshots T=1000, tests different signal-to-noise ratio respectively Under, institute's extracting method of the present invention passes through root-mean-square error to the power accuracy of estimation in individual signals source and 30 signal sources (RMSE) it indicates, calculation formula is:
Wherein, Q is Monte Carlo experiment number,Indicate that the power of first of signal in the q times Monte Carlo experiment is estimated Evaluation,For the actual power of first of signal.In this emulation, Q=1000.The case where for individual signals source, covers special every time Signal source incident direction meets Gaussian Profile in the experiment of CarlowThe case where for 30 signal sources, signal Source incident direction is distributed evenly within the scope of 45 ° to 135 ° this space angle domains.To individual signals source under different signal-to-noise ratio It is as shown in Figure 4 with the power accuracy of estimation of 30 signal sources.As can be seen that in the two kinds of feelings in individual signals source and 30 signal sources Under condition, institute's extracting method power estimation error of the present invention is respectively less than 1dB, can relatively accurately carry out the estimation of signal power.
Simulation example 2:Using relatively prime array received incoming signal identical with simulation example 1, signal-to-noise ratio is set as 10dB, It is tested respectively in different sampling number of snapshots, power of the institute's extracting method of the present invention to individual signals source and 30 signal sources Accuracy of estimation, other simulated conditions keep identical with simulation example 1.Individual signals source and 30 under the conditions of difference sampling number of snapshots Power accuracy of estimation is as shown in Figure 5 in the case of a signal source.As can be seen that in the case of individual signals source, power estimation Root-mean-square error be respectively less than 1dB;In the case of 30 signal sources, power estimation is square when sampling number of snapshots are more than 300 Root error is reduced to 1dB or less.Therefore, institute's extracting method of the present invention can relatively accurately carry out the estimation of signal power.
Simulation example 3:Using relatively prime array received incoming signal identical with simulation example 1, signal-to-noise ratio is set as 10dB, Sampling number of snapshots are set as T=500.It is assumed that incident narrow band signal number is 30, incident direction be uniformly distributed in 45 ° to 135 ° this Within the scope of one space angle domain.Space power spectrum that institute's extracting method of the present invention obtains as shown in fig. 6, wherein vertical dotted line represent into Penetrate the true directions of signal source.As can be seen that institute's extracting method of the present invention can effectively differentiate this 30 incident signal sources.For passing System can only at most differentiate 26 incident letters using the Wave arrival direction estimating method of uniform linear array using 27 physics array elements Number, result above, which embodies institute's extracting method of the present invention, realizes the increase of degree of freedom.
In conclusion institute's extracting method of the present invention passes through the second order equivalence virtual signal to being described using angle-spatial frequency It carries out inverse discrete Fourier transform to obtain its roomage response and build a space power spectrum based on this, by constructed space The spectrum peak search process of power spectrum obtains DOA estimations, while ensureing that DOA estimates degree of freedom performance boost, obtains corresponding letter Number power estimation value.The operation of inverse discrete Fourier transform significantly reduces computation complexity, preferably meets to reality The practical application scene that when property has higher requirements, while being easy to hardware realization in systems in practice.
Above-described embodiment is used for illustrating the present invention, rather than limits the invention, the present invention spirit and In scope of the claims, to any modifications and changes that the present invention makes, protection scope of the present invention is both fallen within.

Claims (7)

1. a kind of Wave arrival direction estimating method based on relatively prime array second order equivalence virtual signal inverse discrete Fourier transform, special Sign is, comprises the steps of:
(1) receiving terminal uses 2M+N-1 array element, and carries out framework according to relatively prime array structure;Wherein M and N is relatively prime integer;
(2) assume there are L to come from θ=s [θ12,…,θL]TThe far field narrowband incoherent signal source , &#91 in direction;·]TIndicate transposition behaviour Make, incoming signal is received using the relatively prime array built in step (1), then in the relatively prime array received signal x of t moment (t) it can be modeled as:
Wherein, x (t) is (2M+N-1) × 1 dimensional vector, sl(t) be first of incoming signal waveform, n (t) be and each signal source phase Mutual independent noise component(s), a (θl) it is corresponding to θlThe relatively prime array steering vector in direction signal source, is represented by
Wherein, μi, i=1,2,3 ..., 2M+N-1 indicate the physical location of i-th of physics array element in relatively prime array, and first physics The position of array element is μ1=0, λ are the wavelength of incident narrow band signal, and j is imaginary unit.
Covariance matrix is built according to relatively prime array received signal x (t):The sampling covariance square obtained using T sampling snap Battle arrayTo theoretical covariance matrix RxCarry out approximate substitution;
(3) the second order equivalence virtual signal corresponding to the virtual uniform linear array of augmentation is derived according to relatively prime array received signal: Pass through vectorization sample covariance matrixObtain virtual array equivalence virtual signal y:
Wherein,For (2M+N- 1)2× L ties up guiding matrix,To include the vector of L incoming signal source power,For noise Power, i=vec (I2M+N-1), I2M+N-1Indicate that (2M+N-1) × (2M+N-1) ties up unit matrix, vec () indicates vectorization behaviour Make, i.e., each row in matrix is stacked gradually to form a new vector, ()*Indicate conjugate operation,It indicates in Crow Gram product;
The corresponding non-homogeneous virtual array S of vectorial yDIt is expressed as:
SD={ ± (Mn-Nm) d, 0≤n≤N-1,0≤m≤2M-1 },
Wherein d is the half of incident narrow band signal wavelength, i.e.,
Choose non-homogeneous virtual array SDThe Virtual array of middle maximum continuous part, composition one include 2V+1 Virtual array Virtual uniform linear array SV={-Vd ,-(V-1) d ..., 0 ..., (V-1) d, Vd }, V=MN+M-1;
Selection corresponds to S from vectorial yVIn each Virtual array position virtual signal of equal value, composition virtual uniform linear array it is corresponding Second order equivalence virtual signal zθ, it is represented by:
Wherein, B (θ)=s [b(θ1),b(θ2),…b(θL)], l row
To correspond to θlThe virtual uniform linear array steering vector in direction signal source, e are by selecting to correspond to S from iVThe element of middle array element The vector of composition;
(4) it defines angle-spatial frequency and describes the second order equivalence virtual signal of virtual uniform linear array with it.Define angle-sky Between signal week for being propagated within the scope of propagation distance difference between adjacent array element by the narrow band signal from direction θ in space of frequency Issue.The second order equivalence virtual signal z of virtual uniform linear array in step (3)θCan in angle-spatial frequency domain equivalent representation For:
Wherein, B (ξ)=s [b(ξ1),b(ξ2),…b(ξL)], l row ξ=s [ξ12,…,ξL]TIt is right Angle-spatial frequency of L angle included in θ;
(5) inverse discrete Fourier transform is carried out to the second order equivalence virtual signal using angle-spatial frequency description, and builds sky Between power spectrum:The second order equivalence virtual signal z that will be indicated by angle-spatial frequency by inverse discrete Fourier transformξConversion To spatial domain, and then obtain the dimension spaces of its K × 1 response ψ;
A space power spectrum is built, the horizontal axis of the spectrum indicates angle, θ, and the relationship with vectorial k-th of the element of roomage response can It is expressed as:
Wherein, k=0,1 ..., K-1, arccos () are inverse cosine function, and h is to ensureMeet inverse cosine function The coefficient of domain, whenWhen, h=-1, whenWhen, h=0;The longitudinal axis representation space of the spectrum is rung Answer the mould P (k) of k-th of element in vector;
(6) Mutual coupling is carried out according to gained space power spectrum and signal power is estimated.To space power spectrum in step (5) Spectrum peak search operation is carried out, then the corresponding angle of the maximum preceding L peak value of amplitude is that the direction of arrival of L incoming signal is estimated Meter, and its peak amplitude is the power estimation value to induction signal.
2. the wave according to claim 1 based on relatively prime array second order equivalence virtual signal inverse discrete Fourier transform reaches side To method of estimation, it is characterised in that:Relatively prime array structure described in step (1) can be specifically described as:First, one group of selection is relatively prime Integer M, N, a pair of sparse homogenous linear subarray of construction.First subarray includes the array element that 2M spacing is Nd, position It is set to 0, Nd ..., (2M-1) Nd;Second subarray includes the array element that N number of spacing is Md, position 0, Md ..., (N-1) Md.Two subarrays are combined in such a way that first array element overlaps later, obtain including 2M+N-1 physics array element Non-homogeneous relatively prime array.
3. the relatively prime array direction of arrival according to claim 1 based on angle-spatial frequency domain Fast Fourier Transform (FFT) Method of estimation, it is characterised in that:In step (3), if there are multiple and different elements and S in yVIn same Virtual array position correspond to The case where, then select any one in these elements as composition of vector zθElement.
4. the wave according to claim 1 based on relatively prime array second order equivalence virtual signal inverse discrete Fourier transform reaches side To method of estimation, it is characterised in that:Angle-spatial frequency in step (4) is a kind of frequency related with signal incident angle, Particular by being defined such as under type:The narrow band signal arrival intervals from direction θ are that the adjacent array element of d will produce in space One section of propagation distance difference u, is represented by:
U=dcos θ.
Fixed in array element spacing, propagation distance difference u only changes with incoming signal angle, θ, therefore obtains step (4) definition of angle-spatial frequency in.Angle-spatial frequency ξ and the relationship of incoming signal angle, θ are represented by:
5. the wave according to claim 1 based on relatively prime array second order equivalence virtual signal inverse discrete Fourier transform reaches side To method of estimation, it is characterised in that:The second order equivalence virtual signal obtained by inverse discrete Fourier transform in the step (5) zξThe dimension spaces of K × 1 respond ψ, be represented by:
Wherein,Indicate inverse discrete Fourier transform operation, FKFor leaf inverse-transform matrix in K point discrete Fouriers, it is represented by:
The roomage response ψ of gained is the dimensional vectors of K × 1.
6. the relatively prime array direction of arrival according to claim 1 based on angle-spatial frequency domain Fast Fourier Transform (FFT) Method of estimation, it is characterised in that:In the step (5), constructed spatial spectrum reflects the response width in each angle in space Degree, wherein there is the L peak value corresponding to L incoming signal.
7. the wave according to claim 6 based on relatively prime array second order equivalence virtual signal inverse discrete Fourier transform reaches side To method of estimation, it is characterised in that:There is the L peak corresponding to L incoming signal in the step (5) in space power spectrum Value, the conclusion obtain in the following way:Relationship P (k) for building space power spectrum is specifically represented by:
Wherein,For the power of first of signal, δ () indicates impulse function, and r is integer, for indicating that the impulse function is week Phase property impulse string sequence.According to the property of impulse function it is found that only whenWhen, P (k) is peak value.By There is different angle-spatial frequencys in L incoming signal, each angle-spatial frequency energy and be only capable of in space power spectrum Cause a peak value, therefore there is the L peak value corresponding to L incoming signal in space power spectrum.
CN201810460228.7A 2018-05-15 2018-05-15 Direction-of-arrival estimation method based on second-order equivalent virtual signal inverse discrete Fourier transform of co-prime array Active CN108710102B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201810460228.7A CN108710102B (en) 2018-05-15 2018-05-15 Direction-of-arrival estimation method based on second-order equivalent virtual signal inverse discrete Fourier transform of co-prime array

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201810460228.7A CN108710102B (en) 2018-05-15 2018-05-15 Direction-of-arrival estimation method based on second-order equivalent virtual signal inverse discrete Fourier transform of co-prime array

Publications (2)

Publication Number Publication Date
CN108710102A true CN108710102A (en) 2018-10-26
CN108710102B CN108710102B (en) 2020-09-04

Family

ID=63869008

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201810460228.7A Active CN108710102B (en) 2018-05-15 2018-05-15 Direction-of-arrival estimation method based on second-order equivalent virtual signal inverse discrete Fourier transform of co-prime array

Country Status (1)

Country Link
CN (1) CN108710102B (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109471065A (en) * 2018-09-28 2019-03-15 中国电子科技集团公司第三十六研究所 A kind of direction-finding method of coherent signal
CN110133574A (en) * 2019-07-02 2019-08-16 华南理工大学 Utilize the one-dimensional DOA estimation method of the secondary virtual extended of multiple-frequency signal
CN111610486A (en) * 2020-05-03 2020-09-01 浙江大学 High-resolution accurate two-dimensional direction of arrival estimation method based on planar co-prime array virtual domain tensor space spectrum search
CN112162240A (en) * 2020-09-25 2021-01-01 五邑大学 Sparse frequency waveform generation method and device based on co-prime array and storage medium
WO2021068495A1 (en) * 2020-05-03 2021-04-15 浙江大学 Degree of freedom-enhanced spatial spectrum estimation method based on block sampled tensor signal construction using planar co-prime array
CN114167354A (en) * 2021-11-25 2022-03-11 厦门大学 Underwater DOA estimation method based on high degree of freedom
CN115407128A (en) * 2022-07-29 2022-11-29 南京航空航天大学 Power system harmonic and inter-harmonic frequency estimation method based on co-prime sampling
WO2023137812A1 (en) * 2022-01-21 2023-07-27 浙江大学 Coprime planar array two-dimensional direction-of-arrival estimation method based on virtual domain tensor filling

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107015190A (en) * 2017-03-01 2017-08-04 浙江大学 Relatively prime array Wave arrival direction estimating method based on the sparse reconstruction of virtual array covariance matrix
CN107422295A (en) * 2017-08-30 2017-12-01 浙江大学 The Wave arrival direction estimating method represented based on relatively prime array virtual Domain equivalent signal atom norm
CN108680892A (en) * 2018-05-15 2018-10-19 浙江大学 Relatively prime array Wave arrival direction estimating method based on angle-spatial frequency domain Fast Fourier Transform (FFT)

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107015190A (en) * 2017-03-01 2017-08-04 浙江大学 Relatively prime array Wave arrival direction estimating method based on the sparse reconstruction of virtual array covariance matrix
CN107422295A (en) * 2017-08-30 2017-12-01 浙江大学 The Wave arrival direction estimating method represented based on relatively prime array virtual Domain equivalent signal atom norm
CN108680892A (en) * 2018-05-15 2018-10-19 浙江大学 Relatively prime array Wave arrival direction estimating method based on angle-spatial frequency domain Fast Fourier Transform (FFT)

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
CHENGWEI ZHOU等: "Doa estimation by covariance matrix sparse reconstruction of coprime array", 《 2015 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING (ICASSP)》 *
YANG LIU等: "High-resolution Direction-of-Arrival estimation in SNR and snapshot challenged scenarios using multi-frequency coprime arrays", 《 2017 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING (ICASSP)》 *
YIMIN D. ZHANG等: "Sparsity-based DOA estimation using co-prime arrays", 《 2013 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL PROCESSING》 *

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109471065A (en) * 2018-09-28 2019-03-15 中国电子科技集团公司第三十六研究所 A kind of direction-finding method of coherent signal
CN109471065B (en) * 2018-09-28 2021-05-25 中国电子科技集团公司第三十六研究所 Direction finding method for coherent signals
CN110133574B (en) * 2019-07-02 2022-12-16 华南理工大学 One-dimensional DOA estimation method utilizing secondary virtual expansion of multi-frequency signals
CN110133574A (en) * 2019-07-02 2019-08-16 华南理工大学 Utilize the one-dimensional DOA estimation method of the secondary virtual extended of multiple-frequency signal
CN111610486A (en) * 2020-05-03 2020-09-01 浙江大学 High-resolution accurate two-dimensional direction of arrival estimation method based on planar co-prime array virtual domain tensor space spectrum search
WO2021068495A1 (en) * 2020-05-03 2021-04-15 浙江大学 Degree of freedom-enhanced spatial spectrum estimation method based on block sampled tensor signal construction using planar co-prime array
CN111610486B (en) * 2020-05-03 2022-12-27 浙江大学 High-resolution accurate two-dimensional direction of arrival estimation method based on planar co-prime array virtual domain tensor spatial spectrum search
US11422177B2 (en) 2020-05-03 2022-08-23 Zhejiang University Spatial spectrum estimation method with enhanced degree-of-freedom based on block sampling tensor construction for coprime planar array
CN112162240A (en) * 2020-09-25 2021-01-01 五邑大学 Sparse frequency waveform generation method and device based on co-prime array and storage medium
CN114167354A (en) * 2021-11-25 2022-03-11 厦门大学 Underwater DOA estimation method based on high degree of freedom
WO2023137812A1 (en) * 2022-01-21 2023-07-27 浙江大学 Coprime planar array two-dimensional direction-of-arrival estimation method based on virtual domain tensor filling
CN115407128A (en) * 2022-07-29 2022-11-29 南京航空航天大学 Power system harmonic and inter-harmonic frequency estimation method based on co-prime sampling
CN115407128B (en) * 2022-07-29 2023-10-27 南京航空航天大学 Electric power system harmonic wave and inter-harmonic wave frequency estimation method based on inter-mass sampling

Also Published As

Publication number Publication date
CN108710102B (en) 2020-09-04

Similar Documents

Publication Publication Date Title
CN108710102A (en) Wave arrival direction estimating method based on relatively prime array second order equivalence virtual signal inverse discrete Fourier transform
CN104749553B (en) Direction of arrival angle method of estimation based on rapid sparse Bayesian learning
CN107102291B (en) The relatively prime array Wave arrival direction estimating method of mesh freeization based on virtual array interpolation
CN107315160B (en) Relatively prime array Wave arrival direction estimating method based on interpolation virtual array signal atom norm minimum
CN107290709B (en) The relatively prime array Wave arrival direction estimating method decomposed based on vandermonde
CN104698433B (en) DOA Estimation in Coherent Signal method based on single snapshot data
CN108872929A (en) Relatively prime array Wave arrival direction estimating method based on interpolation virtual array covariance matrix Subspace Rotation invariance
CN109143152B (en) Polarized array direction of arrival and polarization estimation method based on tensor modeling
CN112073895A (en) High-precision personnel positioning and tracking method based on CSI
CN107015190A (en) Relatively prime array Wave arrival direction estimating method based on the sparse reconstruction of virtual array covariance matrix
CN106324558A (en) Broadband signal DOA estimation method based on co-prime array
CN107092004A (en) Relatively prime array Wave arrival direction estimating method based on signal subspace rotational invariance
CN103364772B (en) Target low elevation estimation method based on real number field generalized multiple-signal sorting algorithm
CN107589399A (en) Based on the relatively prime array Wave arrival direction estimating method for sampling virtual signal singular values decomposition more
CN103323827B (en) Method for MIMO radar system angle estimation based on fast Fourier transformation
CN104459667B (en) Sparse array DOA estimation method based on CLEAN
CN104515969B (en) Hexagonal array-based coherent signal two-dimensional DOA (Direction of Arrival) estimation method
CN109471086A (en) Relatively prime MIMO radar Wave arrival direction estimating method based on more sampling snap sum aggregate array signal discrete Fourier transforms
Yang et al. Decimeter level indoor localization using WiFi channel state information
CN106896340A (en) A kind of relatively prime array high accuracy Wave arrival direction estimating method based on compressed sensing
CN107255796A (en) Arrowband near-field signals source localization method under a kind of non-uniform noise
CN111580042B (en) Deep learning direction finding method based on phase optimization
CN103713276A (en) Arrival direction estimation method based on minimum mutual entropy spectrum analysis
CN108614234B (en) Direction-of-arrival estimation method based on multi-sampling snapshot co-prime array received signal fast Fourier inverse transformation
CN106125039B (en) Improvement space-time adaptive Monopulse estimation method based on local Combined Treatment

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