WO2021068495A1 - 基于平面互质阵列块采样张量信号构造的自由度增强型空间谱估计方法 - Google Patents

基于平面互质阵列块采样张量信号构造的自由度增强型空间谱估计方法 Download PDF

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WO2021068495A1
WO2021068495A1 PCT/CN2020/088568 CN2020088568W WO2021068495A1 WO 2021068495 A1 WO2021068495 A1 WO 2021068495A1 CN 2020088568 W CN2020088568 W CN 2020088568W WO 2021068495 A1 WO2021068495 A1 WO 2021068495A1
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tensor
signal
array
virtual domain
axis
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PCT/CN2020/088568
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French (fr)
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陈积明
郑航
史治国
周成伟
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浙江大学
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Publication of WO2021068495A1 publication Critical patent/WO2021068495A1/zh
Priority to US17/395,480 priority patent/US11422177B2/en

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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R29/00Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
    • G01R29/08Measuring electromagnetic field characteristics
    • G01R29/0864Measuring electromagnetic field characteristics characterised by constructional or functional features
    • G01R29/0892Details related to signal analysis or treatment; presenting results, e.g. displays; measuring specific signal features other than field strength, e.g. polarisation, field modes, phase, envelope, maximum value
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R29/00Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
    • G01R29/08Measuring electromagnetic field characteristics
    • G01R29/10Radiation diagrams of antennas
    • 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
    • G01S3/74Multi-channel systems specially adapted for direction-finding, i.e. having a single antenna system capable of giving simultaneous indications of the directions of different signals
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F18/00Pattern recognition
    • G06F18/20Analysing
    • G06F18/21Design or setup of recognition systems or techniques; Extraction of features in feature space; Blind source separation
    • G06F18/211Selection of the most significant subset of features
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F18/00Pattern recognition
    • G06F18/20Analysing
    • G06F18/21Design or setup of recognition systems or techniques; Extraction of features in feature space; Blind source separation
    • G06F18/211Selection of the most significant subset of features
    • G06F18/2113Selection of the most significant subset of features by ranking or filtering the set of features, e.g. using a measure of variance or of feature cross-correlation
    • 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
    • G01S3/04Details
    • G01S3/043Receivers
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01QANTENNAS, i.e. RADIO AERIALS
    • H01Q21/00Antenna arrays or systems
    • H01Q21/06Arrays of individually energised antenna units similarly polarised and spaced apart
    • H01Q21/22Antenna units of the array energised non-uniformly in amplitude or phase, e.g. tapered array or binomial array

Definitions

  • the invention belongs to the field of array signal processing technology, and in particular relates to a spatial spectrum estimation technology based on planar coprime array tensor signal modeling and statistical processing, in particular to a degree of freedom enhanced type based on the structure of planar coprime array block sampling tensor signal
  • the spatial spectrum estimation method can be used for passive detection and positioning.
  • the planar coprime array has the characteristics of large aperture and high degree of freedom, and can realize high-precision and high-resolution spatial spectrum estimation; at the same time, by constructing a two-dimensional virtual domain and Processing based on second-order virtual domain statistics can effectively improve the degree of freedom of signal source spatial resolution.
  • the traditional spatial spectrum estimation method usually expresses the incident signal with two-dimensional spatial structure information as a vector, calculates the second-order statistics of the multi-sampled signal in a time average manner, and then derives the second-order equivalent signal in the virtual domain through vectorization.
  • the spatial smoothing method is used to solve the rank deficiency problem of the signal covariance matrix of the single snapshot virtual domain to construct the spatial spectrum.
  • the planar coprime array received signal and its virtual domain second-order equivalent signal expressed in a vector manner not only lose the multi-dimensional spatial structure information of the original signal, but also easily cause dimensional disasters as the amount of data increases; on the other hand, on the one hand, the construction of the spatial spectrum function based on the single-shot virtual domain signal introduces a means of spatial smoothing, which causes a certain loss in the degree of freedom performance.
  • the spatial spectrum estimation method based on tensor signal construction began to attract attention.
  • tensors can store the original multi-dimensional information of signals.
  • multi-dimensional algebraic theories such as high-order singular value decomposition and tensor decomposition also provide rich analysis tools for multi-dimensional feature extraction of tensor signals. Therefore, the spatial spectrum estimation method based on tensor signal construction can make full use of the multi-dimensional spatial structure information of the incident signal of the planar coprime array.
  • the existing method is still based on the actual received tensor signal for processing, and does not use the two-dimensional virtual domain of the planar coprime array to construct the tensor space spectrum, and does not achieve the improvement of the degree of freedom performance.
  • the purpose of the present invention is to solve the problem of loss of signal multi-dimensional spatial structure information and loss of freedom in the above-mentioned planar coprime array spatial spectrum estimation method, and propose a freedom-enhanced space based on the structure of planar coprime array block sampling tensor signal.
  • the spectrum estimation method provides feasible ideas and effective solutions for constructing a planar coprime array block sampling tensor signal processing architecture and realizing multi-source tensor spatial spectrum estimation under underdetermined conditions.
  • a degree of freedom enhanced spatial spectrum estimation method based on the construction of planar coprime array block sampling tensor signals, including the following steps:
  • the receiving end uses 4M x M y + N x N y -1 physical antenna elements, which are structured according to the structure of a coprime array; among them, M x , N x and My , N y are a pair respectively Coprime integers, and M x ⁇ N x , My y ⁇ N y ; the coprime array can be decomposed into two sparse uniform sub-arrays with
  • the received signal can be a three-dimensional tensor signal Expressed as:
  • s k [s k,1 ,s k,2 ,...,s k,L ] T is the multi-shot sampling signal waveform corresponding to the k-th incident signal source
  • [ ⁇ ] T represents the transposition operation
  • represents the outer product of the vector
  • Is a noise tensor independent of each signal source
  • the steering vector in the x-axis and y-axis directions corresponds to the direction of the incoming wave as
  • the signal source is expressed as:
  • the received signal can be another three-dimensional tensor Expressed as:
  • ( ⁇ ) * represents the conjugate operation
  • the steering vector in the x-axis and y-axis directions corresponds to the direction of the incoming wave as Signal source; Represents the power of the k-th incident signal source; here, Represents the Kronecker product; the tensor subscript represents the modulus expansion operation of the tensor PARAFAC decomposition;
  • the steering vector in the x-axis and y-axis directions corresponds to the direction of the incoming wave as Signal source;
  • Means The r-th slice in the direction of the third dimension ie, the equivalent sampling time series information dimension represented by block sampling
  • CANDECOMP/PARACFAC the factor vector decomposed by CANDECOMP/PARACFAC, which respectively represent the spatial information in the x-axis direction and the spatial information in the y-axis direction; at this time, the autocorrelation tensor CANDECOMP/PARACFAC decomposes the theoretical maximum value of the number of resolvable sources K, which exceeds the actual number of physical array elements; further, construct the signal subspace Express it as:
  • ortho( ⁇ ) represents the matrix orthogonalization operation; further, use Represents the noise subspace, then with The following relationships exist:
  • I represents the identity matrix
  • ( ⁇ ) H represents the conjugate transpose operation
  • the ideal (no noise scene) can be modeled as:
  • the virtual domain tensor signal The first two dimensions represent the spatial information of the virtual domain uniform area array in the x-axis and y-axis directions, and the third dimension represents the equivalent sampling time series information constructed by block sampling, the virtual domain tensor signal.
  • the fourth-order autocorrelation tensor is directly calculated, without the need to introduce a spatial smoothing process to compensate for the rank loss problem caused by the single-shot virtual domain signal.
  • the number of distinguishable information sources K of the method proposed in the present invention is greater than the number of actual physical array elements, and the maximum value of K is Represents the rounding operation.
  • step (7) the signal and noise subspace obtained by the CANDECOMP/PARACFAC decomposition of the virtual domain fourth-order autocorrelation tensor are used to construct the tensor space spectral function.
  • the two-dimensional direction of arrival for spectral peak search is defined And construct a uniform area array corresponding to the virtual domain Guide information Expressed as:
  • the present invention has the following advantages:
  • the present invention uses a tensor to represent the actual received signal of the plane coprime, which is different from the traditional method of vectorizing the two-dimensional spatial information and averaging the snapshot information to obtain the second-order statistics.
  • the present invention takes the snapshots of each sample The signal is superimposed in the third dimension, and the second-order cross-correlation tensor containing the four-dimensional spatial information is used to estimate the spatial spectrum, and the multi-dimensional spatial structure information of the actual incident signal of the planar coprime array is retained;
  • the present invention constructs the tensor signal by means of block sampling, and derives the block sampling virtual domain tensor signal with equivalent sampling time sequence information.
  • the virtual domain tensor signal is the same as the plane coprime array actually receiving the tensor signal.
  • the quantity signal has the same structure, and its fourth-order autocorrelation tensor can be directly derived, without the need to introduce spatial smoothing and other operations to solve the rank deficit problem of the single snapshot virtual domain signal, which effectively reduces the loss of degrees of freedom;
  • the present invention uses the tensor CANDECOMP/PARACFAC decomposition method to extract the multi-dimensional features of the fourth-order autocorrelation tensor of the block-sampled virtual domain tensor signal, thereby establishing the relationship between the virtual domain tensor signal and the signal and noise subspace
  • the internal connection of provides a basis for constructing a tensor space spectrum with enhanced degrees of freedom.
  • Figure 1 is a block diagram of the overall flow of the present invention.
  • Fig. 2 is a schematic diagram of the structure of the planar coprime array in the present invention.
  • FIG. 3 is a schematic diagram of the structure of the augmented virtual domain area array derived by the present invention.
  • the present invention provides a degree of freedom enhanced spatial spectrum estimation method based on the construction of planar coprime array block sampling tensor signals.
  • the virtual domain statistics based on the block sampling tensor signal statistics are derived, and the virtual domain tensor signal with equivalent sampling time series information is constructed; there is no need to introduce spatial smoothing
  • the fourth-order autocorrelation tensor of the virtual domain tensor signal is decomposed by CANDECOMP/PARACFAC to obtain the signal and noise subspace, thereby constructing the tensor space spectrum function with enhanced degree of freedom.
  • the implementation steps of the present invention are as follows:
  • Step 1 Construct a planar coprime array.
  • 4M x M y +N x N y -1 physical antenna elements are used to construct a planar coprime array, as shown in Figure 2:
  • Contains N x ⁇ N y antenna array elements the distance between the elements in the x-axis direction and the y-axis direction is M x d and My y d respectively, and the
  • Step 2 Planar coprime array block sampling signal tensor modeling.
  • T r 1,2, ... , R
  • R the number of sample blocks; each block Within the sampling range, the sparse sub-array of the planar coprime array
  • the snapshot signals of each sample are superimposed in the third dimension to obtain a three-dimensional block sampling tensor signal Expressed as:
  • s k [s k,1 ,s k,2 ,...,s k,L ] T is the multi-shot sampling signal waveform corresponding to the k-th incident signal source
  • [ ⁇ ] T represents the transposition operation
  • represents the outer product of the vector
  • Is a noise tensor independent of each signal source
  • the steering vector in the x-axis and y-axis directions corresponds to the direction of the incoming wave as
  • the signal source is expressed as:
  • the sparse subarray A block sampled signal of can be used with another three-dimensional tensor Expressed as:
  • ( ⁇ ) * represents the conjugate operation
  • Step 3 Derive the virtual domain equivalent signal based on the cross-correlation statistics of the block sampled tensor signal.
  • the second-order cross-correlation tensor of the two sub-array blocks of the planar coprime array sampling the received tensor signal The ideal modeling (no noise scene) is:
  • the equivalent of the received signal will be the cross-correlation tensor
  • the first and third dimensions representing the spatial information in the x-axis direction are merged into one dimension, and the second and fourth dimensions representing the spatial information in the y-axis direction are merged into another dimension.
  • the dimensional merging of tensors can be achieved through the modular expansion operation of its PARAFAC decomposition, with a four-dimensional tensor For example, define a collection of dimensions with then PARAFAC decomposition model The expansion operation is as follows:
  • the tensor subscript represents the modulus expansion operation of the tensor PARAFAC decomposition, with Represents the factor vector of the two dimensions after expansion; here, Represents Kronecker product. Therefore, define a collection of dimensions with Cross-correlation tensor Model for PARAFAC decomposition Expand to get an augmented virtual domain area array Equivalent received signal Expressed as:
  • the steering vector in the x-axis and y-axis directions corresponds to the direction of the incoming wave as Signal source;
  • V x M x N x +M x +N x -1
  • V y M y N y +M y +N y -1
  • virtual domain uniform area array The structure of is shown in the dashed box in Figure 3, expressed as:
  • Augmented virtual domain array Equivalent with the received signal U r
  • the elements corresponding to the position of each virtual array element can be obtained as a uniform area array of the virtual domain
  • the block sampling is equivalent to the received signal
  • the steering vector in the x-axis and y-axis directions corresponds to the direction of the incoming wave as Signal source;
  • Step 5 Construct a three-dimensional block sampling virtual domain tensor signal and its fourth-order autocorrelation tensor.
  • R block samples T r (r 1,2, ... , R) corresponding to the virtual domain signals to obtain R
  • These R virtual domain signals Superimpose in the third dimension to get a three-dimensional tensor signal
  • the virtual domain tensor signal The first two dimensions represent the spatial information of the virtual domain uniform area array in the x-axis and y-axis directions, and the third dimension represents the equivalent sampling time series information constructed by block sampling. It can be seen that the virtual domain tensor Actually receive the tensor signal with the planar coprime array with Have the same structure.
  • Tensor signal for virtual domain The fourth-order autocorrelation tensor can be obtained directly, without the need to introduce a spatial smoothing process to compensate for the rank loss problem caused by the single block beat virtual domain signal, and the block sampling virtual domain tensor signal Fourth-order autocorrelation tensor Express it as:
  • Means The r-th slice in the direction of the third dimension ie, the equivalent sampling time series information dimension represented by block sampling
  • Step 6 Construct the signal and noise subspace based on the fourth-order autocorrelation tensor decomposition of the virtual domain.
  • the fourth-order autocorrelation tensor Perform CANDECOMP/PARACFAC decomposition to extract multi-dimensional features, and the results obtained are expressed as follows:
  • CANDECOMP/PARACFAC decomposition which respectively represents the spatial information along the x-axis direction and the y-axis direction; with Represents the factor matrix.
  • CANDECOMP/PARACFAC decomposition follows the uniqueness condition as follows:
  • the number of distinguishable incident information sources K of the method proposed in the present invention is greater than the number of actual physical array elements, and the maximum value of K is Represents the rounding operation. Further, the multi-dimensional features obtained by tensor decomposition are used to construct the signal subspace
  • ortho( ⁇ ) represents the matrix orthogonalization operation; use Represents the noise subspace, then with The following relationships exist:
  • I represents the identity matrix
  • ( ⁇ ) H represents the conjugate transpose operation
  • Step 7 The degree of freedom enhanced tensor spatial spectrum estimation. Define the two-dimensional direction of arrival for spectral peak search And construct a uniform area array corresponding to the virtual domain Guide information Expressed as:
  • the present invention fully considers the multi-dimensional information structure of the planar coprime array signal, uses block sampling tensor signal modeling, constructs a virtual domain tensor signal with equivalent sampling time series information, and further uses tensor Decompose the multi-dimensional feature extraction of the fourth-order statistics of the block-sampled virtual domain tensor signal to construct a signal and noise subspace based on the block-sampled virtual domain tensor signal, and establish a planar coprime array block-sampled virtual domain tensor signal
  • the present invention obtains a virtual domain tensor signal with a three-dimensional information structure through the block sampling structure, thereby avoiding the statistical analysis of the virtual domain equivalent received signal in order to solve the single block Shooting the virtual domain is equivalent to the rank deficit problem of the received signal, which requires the introduction of a spatial smoothing process, making full use of the advantages of the degree of freedom brought by the virtual domain of the planar coprime array, and realizing the multi-source ten

Abstract

一种基于平面互质阵列块采样张量信号构造的自由度增强型空间谱估计方法,主要解决现有方法中信号多维信息丢失和自由度受限问题,其实现步骤是:构建平面互质阵列;平面互质阵列块采样信号张量建模;推导基于块采样张量信号互相关统计量的虚拟域等价信号;获取虚拟域均匀面阵的块采样等价接收信号;构造三维块采样虚拟域张量信号及其四阶自相关张量;构造基于虚拟域四阶自相关张量分解的信号与噪声子空间;自由度增强型张量空间谱估计。基于块采样方式构造平面互质阵列张量信号,并推导虚拟域等价张量信号,进而通过四阶自相关张量中信号与噪声子空间特征的提取,实现自由度增强的张量空间谱估计,可用于无源探测与定位。

Description

基于平面互质阵列块采样张量信号构造的自由度增强型空间谱估计方法 技术领域
本发明属于阵列信号处理技术领域,尤其涉及基于平面互质阵列张量信号建模与统计处理的空间谱估计技术,具体是一种基于平面互质阵列块采样张量信号构造的自由度增强型空间谱估计方法,可用于无源探测与定位。
背景技术
平面互质阵列作为一种具有系统化架构的二维稀疏阵列,具有大孔径、高自由度的特点,能够实现高精度、高分辨的空间谱估计;与此同时,通过构造二维虚拟域并基于二阶虚拟域统计量进行处理,能够有效提升信号源空间分辨的自由度。传统的空间谱估计方法通常将具有二维空间结构信息的入射信号用矢量进行表示,以时间平均的方式计算多采样信号的二阶统计量,进而通过矢量化推导虚拟域二阶等价信号,并通过空间平滑的手段解决单快拍虚拟域信号协方差矩阵的秩亏问题以构造空间谱。然而,一方面,以矢量方式表示的平面互质阵列接收信号及其虚拟域二阶等价信号不仅丢失了原始信号的多维空间结构信息,且随着数据量增大,容易造成维度灾难;另一方面,基于单快拍虚拟域信号的空间谱函数构造引入了空间平滑的手段,对自由度性能造成了一定的损失。
为了解决上述问题,基于张量信号构造的空间谱估计方法开始受到关注。张量作为一种高维的数据结构,可以保存信号的原始多维信息;同时,高阶奇异值分解、张量分解等多维代数理论也为张量信号的多维特征提取提供了丰富的分析工具。因此,基于张量信号构造的空间谱估计方法能够充分利用平面互质阵列入射信号的多维空间结构信息。然而,现有方法仍然是基于实际接收张量信号进行处理,并没有利用平面互质阵列的二维虚拟域进行张量空间谱构造,且没有实现自由度性能的提升。
发明内容
本发明的目的在于针对上述平面互质阵列空间谱估计方法中存在的信号多维空间结构信息丢失和自由度损失问题,提出一种基于平面互质阵列块采样张量信号构造的自由度增强型空间谱估计方法,为构建平面互质阵列块采样张量信号处理架构,实现欠定条件下的多信源张量空间谱估计提供了可行的思路和有效的解决方案。
本发明的目的是通过以下技术方案实现的:一种基于平面互质阵列块采样张量信号构造的自由度增强型空间谱估计方法,包含以下步骤:
(1)接收端使用4M xM y+N xN y-1个物理天线阵元,按照互质面阵的结构进行架构;其中,M x、N x以及M y、N y分别为一对互质整数,且M x<N x,M y<N y;该互质面阵可分解为两个稀疏均匀子阵列
Figure PCTCN2020088568-appb-000001
Figure PCTCN2020088568-appb-000002
(2)假设有K个来自
Figure PCTCN2020088568-appb-000003
方向的远场窄带非相干信号源,取L个采样快拍作为一个块采样,记为T r(r=1,2,…,R),R为块采样个数;每个块采样范围内,平面互质阵列稀疏子阵列
Figure PCTCN2020088568-appb-000004
的接收信号可用一个三维张量信号
Figure PCTCN2020088568-appb-000005
表示为:
Figure PCTCN2020088568-appb-000006
其中,s k=[s k,1,s k,2,…,s k,L] T为对应第k个入射信源的多快拍采样信号波形,[·] T表示转置操作,ο表示矢量外积,
Figure PCTCN2020088568-appb-000007
为与各信号源相互独立的噪声张量,
Figure PCTCN2020088568-appb-000008
Figure PCTCN2020088568-appb-000009
分别为
Figure PCTCN2020088568-appb-000010
在x轴和y轴方向上的导引矢量,对应于来波方向为
Figure PCTCN2020088568-appb-000011
的信号源,表示为:
Figure PCTCN2020088568-appb-000012
Figure PCTCN2020088568-appb-000013
其中,
Figure PCTCN2020088568-appb-000014
Figure PCTCN2020088568-appb-000015
分别表示稀疏子阵列
Figure PCTCN2020088568-appb-000016
在x轴和y轴方向上第i 1和i 2个物理天线阵元的实际位置,且
Figure PCTCN2020088568-appb-000017
Figure PCTCN2020088568-appb-000018
每个块采样范围内,稀疏子阵列
Figure PCTCN2020088568-appb-000019
的接收信号可用另一个三维张量
Figure PCTCN2020088568-appb-000020
表示为:
Figure PCTCN2020088568-appb-000021
其中,
Figure PCTCN2020088568-appb-000022
为与各信号源相互独立的噪声张量,
Figure PCTCN2020088568-appb-000023
Figure PCTCN2020088568-appb-000024
分别为稀疏子阵列
Figure PCTCN2020088568-appb-000025
在x轴和y轴方向上的导引矢量,对应于来波方向为
Figure PCTCN2020088568-appb-000026
的信号源,表示为:
Figure PCTCN2020088568-appb-000027
Figure PCTCN2020088568-appb-000028
其中,
Figure PCTCN2020088568-appb-000029
Figure PCTCN2020088568-appb-000030
分别表示稀疏子阵列
Figure PCTCN2020088568-appb-000031
在x轴和y轴方向上第i 3和i 4个物理天线阵元的实际位置,且
Figure PCTCN2020088568-appb-000032
对于一个块采样T r(r=1,2,…,R),计算该块采样范围内子阵列
Figure PCTCN2020088568-appb-000033
Figure PCTCN2020088568-appb-000034
的接收张量信号
Figure PCTCN2020088568-appb-000035
Figure PCTCN2020088568-appb-000036
的二阶互相关张量
Figure PCTCN2020088568-appb-000037
表示为:
Figure PCTCN2020088568-appb-000038
这里,
Figure PCTCN2020088568-appb-000039
Figure PCTCN2020088568-appb-000040
分别表示
Figure PCTCN2020088568-appb-000041
Figure PCTCN2020088568-appb-000042
在第三维度(即快拍维度)方向上的第l个切片,(·) *表示共轭操作;
(3)由互相关张量
Figure PCTCN2020088568-appb-000043
得到一个增广的非均匀虚拟域面阵
Figure PCTCN2020088568-appb-000044
其中各虚拟阵元的位置表示为:
Figure PCTCN2020088568-appb-000045
其中,单位间隔d取为入射窄带信号波长λ的一半,即d=λ/2。定义维度集合
Figure PCTCN2020088568-appb-000046
Figure PCTCN2020088568-appb-000047
则通过对互相关张量
Figure PCTCN2020088568-appb-000048
的理想值
Figure PCTCN2020088568-appb-000049
(无噪声场景)进行PARAFAC分解的模
Figure PCTCN2020088568-appb-000050
展开,可获得增广虚拟域面阵
Figure PCTCN2020088568-appb-000051
的等价接收信号
Figure PCTCN2020088568-appb-000052
的理想表示为:
Figure PCTCN2020088568-appb-000053
其中,
Figure PCTCN2020088568-appb-000054
Figure PCTCN2020088568-appb-000055
Figure PCTCN2020088568-appb-000056
是增广虚拟域面阵
Figure PCTCN2020088568-appb-000057
在x轴和y轴方向上的导引矢量,对应于来波方向为
Figure PCTCN2020088568-appb-000058
的信号源;
Figure PCTCN2020088568-appb-000059
表示第k个入射信号源的功率;这里,
Figure PCTCN2020088568-appb-000060
表示克罗内克积;张量下标表示张量PARAFAC分解的模展开操作;
(4)
Figure PCTCN2020088568-appb-000061
中包含一个x轴分布为(-N x+1)d到(M xN x+M x-1)d、y轴分布为(-N y+1)d到(M yN y+M y-1)d的连续均匀虚拟域面阵
Figure PCTCN2020088568-appb-000062
中共有V x×V y个虚拟阵元,其中V x=M xN x+M x+N x-1,V y=M yN y+M y+N y-1,
Figure PCTCN2020088568-appb-000063
表示为:
Figure PCTCN2020088568-appb-000064
通过选取虚拟域等价接收信号U r中与
Figure PCTCN2020088568-appb-000065
各虚拟阵元位置相对应的元素,获取虚拟域均匀面阵
Figure PCTCN2020088568-appb-000066
的块采样等价接收信号
Figure PCTCN2020088568-appb-000067
将其表示为:
Figure PCTCN2020088568-appb-000068
其中,
Figure PCTCN2020088568-appb-000069
Figure PCTCN2020088568-appb-000070
Figure PCTCN2020088568-appb-000071
Figure PCTCN2020088568-appb-000072
为虚拟域均匀面阵
Figure PCTCN2020088568-appb-000073
在x轴和y轴方向上的导引矢量,对应于来波方向为
Figure PCTCN2020088568-appb-000074
的信号源;
(5)按照前述步骤,取R个块采样T r(r=1,2,…,R)对应得到R个虚拟域信号
Figure PCTCN2020088568-appb-000075
将这R个虚拟域信号
Figure PCTCN2020088568-appb-000076
在第三维度上进行叠加,得到一个第三维度表示等效采样时间信息的虚拟域张量信号
Figure PCTCN2020088568-appb-000077
求块采样虚拟域张量信号
Figure PCTCN2020088568-appb-000078
的四阶自相关张量
Figure PCTCN2020088568-appb-000079
将其表示为:
Figure PCTCN2020088568-appb-000080
其中,
Figure PCTCN2020088568-appb-000081
表示
Figure PCTCN2020088568-appb-000082
在第三维度(即通过块采样所表征的等效采样时间序列信息维度)方向上的第r个切片;
(6)对虚拟域四阶自相关张量
Figure PCTCN2020088568-appb-000083
进行CANDECOMP/PARACFAC分解以提取多维特征,得到结果表示如下:
Figure PCTCN2020088568-appb-000084
其中,
Figure PCTCN2020088568-appb-000085
Figure PCTCN2020088568-appb-000086
为CANDECOMP/PARACFAC分解得到的因子矢量,分别表示x轴方向空间信息和y轴方向空间信息;此时,自相关张量
Figure PCTCN2020088568-appb-000087
CANDECOMP/PARACFAC分解可分辨的信源个数K的理论最大值,超过实际物理阵元个数;进一步地,构造信号子空间
Figure PCTCN2020088568-appb-000088
将其表示为:
Figure PCTCN2020088568-appb-000089
其中,orth(·)表示矩阵正交化操作;进一步地,用
Figure PCTCN2020088568-appb-000090
表示噪声子空间,则
Figure PCTCN2020088568-appb-000091
Figure PCTCN2020088568-appb-000092
存在以下关系:
Figure PCTCN2020088568-appb-000093
其中,I表示单位矩阵;(·) H表示共轭转置操作;
(7)根据得到的信号子空间和噪声子空间,构造自由度增强的张量空间谱函数,得到对应二维波达方向的空间谱估计。
进一步地,步骤(1)所述的互质面阵结构可具体描述为:在平面坐标系xoy上构造一对稀疏均匀平面子阵列
Figure PCTCN2020088568-appb-000094
Figure PCTCN2020088568-appb-000095
其中
Figure PCTCN2020088568-appb-000096
包含2M x×2M y个天线阵元,在x轴方向上和y轴方向上的阵元间距分别为N xd和N yd,其在xoy上的位置坐标为{(N xdm x,N ydm y),m x=0,1,...,2M x-1,m y=0,1,...,2M y-1};
Figure PCTCN2020088568-appb-000097
包含N x×N y个天线阵元,在x轴方向上和y轴方向上的阵元间距分别为M xd和M yd,其在xoy上的位置坐标为{(M xdn x,M ydn y),n x=0,1,...,N x-1,n y=0,1,...,N y-1};这里,M x、N x以及M y、N y分别为一对互质整数,且M x<N x,M y<N y;将
Figure PCTCN2020088568-appb-000098
Figure PCTCN2020088568-appb-000099
按照(0,0)坐标处阵元重叠的方式进行子阵列组合,获得实际包含4M xM y+N xN y-1个物理天线阵元的互质面阵。
进一步地,步骤(3)所述的互相关张量
Figure PCTCN2020088568-appb-000100
可理想(无噪声场景)建模为:
Figure PCTCN2020088568-appb-000101
此时,
Figure PCTCN2020088568-appb-000102
Figure PCTCN2020088568-appb-000103
等价于沿着x轴的一个增广虚拟域,
Figure PCTCN2020088568-appb-000104
等价于沿着y轴的一个增广虚拟域,从而可以得到非均匀虚拟域面阵
Figure PCTCN2020088568-appb-000105
进一步地,步骤(5)所述的构造对应R个块采样T r(r=1,2,…,R)的虚拟域等价信号
Figure PCTCN2020088568-appb-000106
Figure PCTCN2020088568-appb-000107
沿着第三个维度进行叠加得到虚拟域张量信号
Figure PCTCN2020088568-appb-000108
该虚拟域张量信号
Figure PCTCN2020088568-appb-000109
的前两个维度分别表征虚拟域均匀面阵在x轴和y轴方向上的空间信息,第三个维度表征通过块采样构造的等效采样时间序列信息,虚拟域张量信号
Figure PCTCN2020088568-appb-000110
与平面互质阵列的实际接收张量信号
Figure PCTCN2020088568-appb-000111
Figure PCTCN2020088568-appb-000112
具有相同结构,可以对虚拟域张量信号
Figure PCTCN2020088568-appb-000113
直接求其四阶自相关张量,而不需要引入空间平滑过程来弥补单块拍虚拟域信号带来的秩亏问题。
进一步地,步骤(6)所述的四阶自相关张量
Figure PCTCN2020088568-appb-000114
的CANDECOMP/PARACFAC分解遵循唯一性条件如下:
Figure PCTCN2020088568-appb-000115
其中,
Figure PCTCN2020088568-appb-000116
表示矩阵的Kruskal秩,
Figure PCTCN2020088568-appb-000117
Figure PCTCN2020088568-appb-000118
Figure PCTCN2020088568-appb-000119
表示因子矩阵,且
Figure PCTCN2020088568-appb-000120
Figure PCTCN2020088568-appb-000121
min(·)表示取最小值操作;因此该CANDECOMP/PARACFAC分解唯一性条件转化为:
2min(V x,K)+2min(V y,K)≥2K+3,
根据上述不等式,本发明所提方法的可分辨信源个数K大于实际物理阵元个数,K的最大值为
Figure PCTCN2020088568-appb-000122
表示取整操作。
进一步地,步骤(7)中利用虚拟域四阶自相关张量CANDECOMP/PARACFAC分解得到的信号和噪声子空间构建张量空间谱函数,首先定义用于谱峰搜索的二维波达方向
Figure PCTCN2020088568-appb-000123
并构造对应虚拟域均匀面阵
Figure PCTCN2020088568-appb-000124
的导引信息
Figure PCTCN2020088568-appb-000125
表示为:
Figure PCTCN2020088568-appb-000126
基于噪声子空间的张量空间谱函数
Figure PCTCN2020088568-appb-000127
表示如下:
Figure PCTCN2020088568-appb-000128
由此,得到对应二维搜索波达方向
Figure PCTCN2020088568-appb-000129
的自由度增强型张量空间谱。
本发明与现有技术相比具有以下优点:
(1)本发明通过张量表示平面互质实际接收信号,不同于传统方法将二维空间信息进行矢量化表征,并将快拍信息进行平均得到二阶统计量,本发明将各采样快拍信号在第三维度上叠加,并利用包含四维空间信息的二阶互相关张量进行空间谱估计,保留了平面互质阵列实际入射信号的多维空间结构信息;
(2)本发明通过块采样的方式进行张量信号构造,并推导得到了具有等效采样时间序列信息的块采样虚拟域张量信号,该虚拟域张量信号与平面互质阵列实际接收张量信号具有相同结构,可直接推导求得其四阶自相关张量,而不需要引入空间平滑等操作来解决单快拍虚拟域信号存在的秩亏问题,有效降低了自由度的损失;
(3)本发明采用张量CANDECOMP/PARACFAC分解的方式对块采样虚拟域张量信号的四阶自相关张量进行多维特征提取,从而建立起虚拟域张量信号与信号与噪声子空间之间的内在联系,为构造自由度增强的张量空间谱提供了基础。
附图说明
图1是本发明的总体流程框图。
图2是本发明中平面互质阵列的结构示意图。
图3是本发明所推导增广虚拟域面阵结构示意图。
具体实施方式
以下参照附图,对本发明的技术方案作进一步的详细说明。
为了解决现有方法存在的信号多维空间结构信息丢失和自由度性能受限问题,本发明提供了一种基于平面互质阵列块采样张量信号构造的自由度增强型 空间谱估计方法。通过对平面互质阵列块采样张量信号进行统计分析,推导基于块采样张量信号统计量的虚拟域统计量,构建具有等效采样时间序列信息的虚拟域张量信号;在无需引入空间平滑过程的条件下,对虚拟域张量信号的四阶自相关张量进行CANDECOMP/PARACFAC分解以获得信号与噪声子空间,从而构造自由度增强的张量空间谱函数。参照图1,本发明的实现步骤如下:
步骤1:构建平面互质阵列。在接收端使用4M xM y+N xN y-1个物理天线阵元构建平面互质阵列,如图2所示:在平面坐标系xoy上构造一对稀疏均匀平面子阵列
Figure PCTCN2020088568-appb-000130
Figure PCTCN2020088568-appb-000131
其中
Figure PCTCN2020088568-appb-000132
包含2M x×2M y个天线阵元,在x轴方向上和y轴方向上的阵元间距分别为N xd和N yd,其在xoy上的位置坐标为{(N xdm x,N ydm y),m x=0,1,...,2M x-1,m y=0,1,...,2M y-1};
Figure PCTCN2020088568-appb-000133
包含N x×N y个天线阵元,在x轴方向上和y轴方向上的阵元间距分别为M xd和M yd,其在xoy上的位置坐标为{(M xdn x,M ydn y),n x=0,1,...,N x-1,n y=0,1,...,N y-1};这里,M x、N x以及M y、N y分别为一对互质整数,且M x<N x,M y<N y;单位间隔d取为入射窄带信号波长λ的一半,即d=λ/2;将
Figure PCTCN2020088568-appb-000134
Figure PCTCN2020088568-appb-000135
按照(0,0)坐标处阵元重叠的方式进行子阵列组合,获得实际包含4M xM y+N xN y-1个物理天线阵元的平面互质阵列;
步骤2:平面互质阵列块采样信号张量建模。假设有K个来自
Figure PCTCN2020088568-appb-000136
方向的远场窄带非相干信号源,取L个连续时间采样快拍作为一个块采样,记作T r(r=1,2,…,R),其中R为块采样个数;每个块采样范围内,将平面互质阵列稀疏子阵列
Figure PCTCN2020088568-appb-000137
的各采样快拍信号在第三维度进行叠加,得到一个三维块采样张量信号
Figure PCTCN2020088568-appb-000138
表示为:
Figure PCTCN2020088568-appb-000139
其中,s k=[s k,1,s k,2,…,s k,L] T为对应第k个入射信源的多快拍采样信号波形,[·] T表示转置操作,ο表示矢量外积,
Figure PCTCN2020088568-appb-000140
为与各信号源相互独立的噪声张量,
Figure PCTCN2020088568-appb-000141
Figure PCTCN2020088568-appb-000142
分别为
Figure PCTCN2020088568-appb-000143
在x轴和y轴方向上的导引矢量,对应于来波 方向为
Figure PCTCN2020088568-appb-000144
的信号源,表示为:
Figure PCTCN2020088568-appb-000145
Figure PCTCN2020088568-appb-000146
其中,
Figure PCTCN2020088568-appb-000147
Figure PCTCN2020088568-appb-000148
分别表示稀疏子阵列
Figure PCTCN2020088568-appb-000149
在x轴和y轴方向上第i 1和i 2个物理天线阵元的实际位置,且
Figure PCTCN2020088568-appb-000150
Figure PCTCN2020088568-appb-000151
类似地,稀疏子阵列
Figure PCTCN2020088568-appb-000152
的一个块采样信号可用另一个三维张量
Figure PCTCN2020088568-appb-000153
Figure PCTCN2020088568-appb-000154
表示为:
Figure PCTCN2020088568-appb-000155
其中,
Figure PCTCN2020088568-appb-000156
为与各信号源相互独立的噪声张量,
Figure PCTCN2020088568-appb-000157
Figure PCTCN2020088568-appb-000158
分别为稀疏子阵列
Figure PCTCN2020088568-appb-000159
在x轴和y轴方向上的导引矢量,对应于来波方向为
Figure PCTCN2020088568-appb-000160
的信号源,表示为:
Figure PCTCN2020088568-appb-000161
Figure PCTCN2020088568-appb-000162
其中,
Figure PCTCN2020088568-appb-000163
Figure PCTCN2020088568-appb-000164
分别表示稀疏子阵列
Figure PCTCN2020088568-appb-000165
在x轴和y轴方向上第i 3和i 4个物理天线阵元的实际位置,且
Figure PCTCN2020088568-appb-000166
对于一个块采样T r(r=1,2,…,R),计算该块采样范围内子阵列
Figure PCTCN2020088568-appb-000167
Figure PCTCN2020088568-appb-000168
的接收张量信号
Figure PCTCN2020088568-appb-000169
Figure PCTCN2020088568-appb-000170
的互相关统计量,得到一个具有四维空间信息的二阶互相关张量
Figure PCTCN2020088568-appb-000171
表示为:
Figure PCTCN2020088568-appb-000172
这里,
Figure PCTCN2020088568-appb-000173
Figure PCTCN2020088568-appb-000174
分别表示
Figure PCTCN2020088568-appb-000175
Figure PCTCN2020088568-appb-000176
在第三维度(即快拍维度)方向上的第l个切片,(·) *表示共轭操作;
步骤3:推导基于块采样张量信号互相关统计量的虚拟域等价信号。平面互 质阵列两个子阵列块采样接收张量信号的二阶互相关张量
Figure PCTCN2020088568-appb-000177
可理想建模(无噪声场景)为:
Figure PCTCN2020088568-appb-000178
其中,
Figure PCTCN2020088568-appb-000179
表示第k个入射信号源的功率;此时,
Figure PCTCN2020088568-appb-000180
Figure PCTCN2020088568-appb-000181
等价于沿着x轴的一个增广虚拟域,
Figure PCTCN2020088568-appb-000182
等价于沿着y轴的一个增广虚拟域,从而可以得到一个增广的非均匀虚拟域面阵
Figure PCTCN2020088568-appb-000183
如图3所示,其中各虚拟阵元的位置表示为:
Figure PCTCN2020088568-appb-000184
为了得到对应于增广虚拟域面阵
Figure PCTCN2020088568-appb-000185
的等价接收信号,将互相关张量
Figure PCTCN2020088568-appb-000186
中表征x轴方向空间信息的第1、3维度合并成一个维度,将表征y轴方向空间信息的第2、4维度合并成另一个维度。张量的维度合并可通过其PARAFAC分解的模展开操作实现,以一个四维张量
Figure PCTCN2020088568-appb-000187
为例,定义维度集合
Figure PCTCN2020088568-appb-000188
Figure PCTCN2020088568-appb-000189
Figure PCTCN2020088568-appb-000190
的PARAFAC分解的模
Figure PCTCN2020088568-appb-000191
展开操作如下:
Figure PCTCN2020088568-appb-000192
其中,张量下标表示张量PARAFAC分解的模展开操作,
Figure PCTCN2020088568-appb-000193
Figure PCTCN2020088568-appb-000194
表示展开后两个维度的因子矢量;这里,
Figure PCTCN2020088568-appb-000195
表示克罗内克积。因此,定义维度集合
Figure PCTCN2020088568-appb-000196
Figure PCTCN2020088568-appb-000197
则通过对互相关张量
Figure PCTCN2020088568-appb-000198
进行PARAFAC分解的模
Figure PCTCN2020088568-appb-000199
展开,可获得增广虚拟域面阵
Figure PCTCN2020088568-appb-000200
的等价接收信号
Figure PCTCN2020088568-appb-000201
表示为:
Figure PCTCN2020088568-appb-000202
其中,
Figure PCTCN2020088568-appb-000203
Figure PCTCN2020088568-appb-000204
Figure PCTCN2020088568-appb-000205
是增广虚拟面阵
Figure PCTCN2020088568-appb-000206
在x轴和y轴方向上的导引矢量,对应于来波方向为
Figure PCTCN2020088568-appb-000207
的信号源;
步骤4:获取虚拟域均匀面阵的块采样等价接收信号。
Figure PCTCN2020088568-appb-000208
中包含一个x轴分布为(-N x+1)d到(M xN x+M x-1)d、y轴分布为(-N y+1)d到(M yN y+M y-1)d的虚拟域均匀面阵
Figure PCTCN2020088568-appb-000209
中共有V x×V y个虚拟阵元,其中V x=M xN x+M x+N x-1,V y=M yN y+M y+N y-1;虚拟域均匀面阵
Figure PCTCN2020088568-appb-000210
的结构如图3中虚线框内所示,表示为:
Figure PCTCN2020088568-appb-000211
通过选取增广虚拟域面阵
Figure PCTCN2020088568-appb-000212
的等价接收信号U r中与
Figure PCTCN2020088568-appb-000213
各虚拟阵元位置相对应的元素,可以获取虚拟域均匀面阵
Figure PCTCN2020088568-appb-000214
的块采样等价接收信号
Figure PCTCN2020088568-appb-000215
Figure PCTCN2020088568-appb-000216
Figure PCTCN2020088568-appb-000217
其中,
Figure PCTCN2020088568-appb-000218
Figure PCTCN2020088568-appb-000219
Figure PCTCN2020088568-appb-000220
为虚拟域均匀面阵
Figure PCTCN2020088568-appb-000221
在x轴和y轴方向上的导引矢量,对应于来波方向为
Figure PCTCN2020088568-appb-000222
的信号源;
步骤5:构造三维块采样虚拟域张量信号及其四阶自相关张量。按照前述步骤,取R个块采样T r(r=1,2,…,R)对应得到R个虚拟域信号
Figure PCTCN2020088568-appb-000223
将这R个虚拟域信号
Figure PCTCN2020088568-appb-000224
在第三维度上进行叠加,得到一个三维张量信号
Figure PCTCN2020088568-appb-000225
该虚拟域张量信号
Figure PCTCN2020088568-appb-000226
的前两个维度分别表征虚拟域均匀面阵在x轴和y轴方向上的空间信息,第三个维度表征通过块采样构造的等效采样时间序列信息。由此可见,虚拟域张量
Figure PCTCN2020088568-appb-000227
与平面互质阵列实际接收张量信号
Figure PCTCN2020088568-appb-000228
Figure PCTCN2020088568-appb-000229
具有相同的结构。对虚拟域张量信号
Figure PCTCN2020088568-appb-000230
可以直接求其四阶自相关张量,不需要引入空间平滑过程弥补单块拍虚拟域信号带来的秩亏问题,求块采样虚拟域张量信号
Figure PCTCN2020088568-appb-000231
的四阶自相关张量
Figure PCTCN2020088568-appb-000232
将其表示为:
Figure PCTCN2020088568-appb-000233
其中,
Figure PCTCN2020088568-appb-000234
表示
Figure PCTCN2020088568-appb-000235
在第三维度(即通过块采样所表征的等效采样时间序列信息维度)方向上的第r个切片;
步骤6:构造基于虚拟域四阶自相关张量分解的信号与噪声子空间。为了构建张量空间谱,对四阶自相关张量
Figure PCTCN2020088568-appb-000236
进行CANDECOMP/PARACFAC分解以提取多维特征,得到结果表示如下:
Figure PCTCN2020088568-appb-000237
其中,
Figure PCTCN2020088568-appb-000238
Figure PCTCN2020088568-appb-000239
为CANDECOMP/PARACFAC分解得到的因子矢量,分别表示沿着x轴方向和y轴方向的空间信息;用
Figure PCTCN2020088568-appb-000240
Figure PCTCN2020088568-appb-000241
Figure PCTCN2020088568-appb-000242
表示因子矩阵。此时,CANDECOMP/PARACFAC分解遵循唯一性条件如下:
Figure PCTCN2020088568-appb-000243
其中,
Figure PCTCN2020088568-appb-000244
表示矩阵的Kruskal秩,且
Figure PCTCN2020088568-appb-000245
Figure PCTCN2020088568-appb-000246
min(·)表示取最小值操作。由此,上述唯一性分解条件可以转化为:
2min(V x,K)+2min(V y,K)≥2K+3.
由上述不等式可知,本发明所提方法的可分辨入射信源个数K大于实际物理阵元个数,K的最大值为
Figure PCTCN2020088568-appb-000247
表示取整操作。进一步地,利用张量分解得到的多维特征,构造信号子空间
Figure PCTCN2020088568-appb-000248
Figure PCTCN2020088568-appb-000249
其中,orth(·)表示矩阵正交化操作;用
Figure PCTCN2020088568-appb-000250
表示噪声子空间,则为
Figure PCTCN2020088568-appb-000251
Figure PCTCN2020088568-appb-000252
存在以下关系:
Figure PCTCN2020088568-appb-000253
其中,I表示单位矩阵;(·) H表示共轭转置操作;
步骤7:自由度增强型张量空间谱估计。定义用于谱峰搜索的二维波达方向
Figure PCTCN2020088568-appb-000254
并构造对应虚拟域均匀面阵
Figure PCTCN2020088568-appb-000255
的导引信息
Figure PCTCN2020088568-appb-000256
表示为:
Figure PCTCN2020088568-appb-000257
基于噪声子空间的张量空间谱函数
Figure PCTCN2020088568-appb-000258
表示如下:
Figure PCTCN2020088568-appb-000259
由此,得到对应二维搜索波达方向
Figure PCTCN2020088568-appb-000260
的自由度增强型张量空间谱。
综上所述,本发明充分考虑了平面互质阵列信号的多维信息结构,利用块采样张量信号建模,构造具有等效采样时间序列信息的虚拟域张量信号,进一步地,利用张量分解对块采样虚拟域张量信号的四阶统计量进行多维特征提取,从而构造基于块采样虚拟域张量信号构造的信号与噪声子空间,建立起平面互质阵列块采样虚拟域张量信号与张量空间谱之间的关联;同时,本发明通过块采样构造得到具有三维信息结构的虚拟域张量信号,从而避免了在对虚拟域等价接收信号进行统计分析时,为了解决单块拍虚拟域等价接收信号的秩亏问题,从而需要引入的空间平滑过程,充分利用平面互质阵列虚拟域带来的自由度优势,实现了自由度增强的多信源张量空间谱估计。
以上所述仅是本发明的优选实施方式,虽然本发明已以较佳实施例披露如上,然而并非用以限定本发明。任何熟悉本领域的技术人员,在不脱离本发明技术方案范围情况下,都可利用上述揭示的方法和技术内容对本发明技术方案做出许多可能的变动和修饰,或修改为等同变化的等效实施例。因此,凡是未脱离本发明技术方案的内容,依据本发明的技术实质对以上实施例所做的任何的简单修改、等同变化及修饰,均仍属于本发明技术方案保护的范围内。

Claims (6)

  1. 一种基于平面互质阵列块采样张量信号构造的自由度增强型空间谱估计方法,其特征在于,包含以下步骤:
    (1)接收端使用4M xM y+N xN y-1个物理天线阵元,按照互质面阵的结构进行架构;其中,M x、N x以及M y、N y分别为一对互质整数,且M x<N x,M y<N y;该互质面阵可分解为两个稀疏均匀子阵列
    Figure PCTCN2020088568-appb-100001
    Figure PCTCN2020088568-appb-100002
    (2)假设有K个来自
    Figure PCTCN2020088568-appb-100003
    方向的远场窄带非相干信号源,取L个采样快拍作为一个块采样,记为T r(r=1,2,…,R),R为块采样个数;每个块采样范围内,平面互质阵列稀疏子阵列
    Figure PCTCN2020088568-appb-100004
    的接收信号可用一个三维张量信号
    Figure PCTCN2020088568-appb-100005
    表示为:
    Figure PCTCN2020088568-appb-100006
    其中,s k=[s k,1,s k,2,…,s k,L] T为对应第k个入射信源的多快拍采样信号波形,
    Figure PCTCN2020088568-appb-100007
    表示转置操作,ο表示矢量外积,
    Figure PCTCN2020088568-appb-100008
    为与各信号源相互独立的噪声张量,
    Figure PCTCN2020088568-appb-100009
    Figure PCTCN2020088568-appb-100010
    分别为
    Figure PCTCN2020088568-appb-100011
    在x轴和y轴方向上的导引矢量,对应于来波方向为
    Figure PCTCN2020088568-appb-100012
    的信号源,表示为:
    Figure PCTCN2020088568-appb-100013
    Figure PCTCN2020088568-appb-100014
    其中,
    Figure PCTCN2020088568-appb-100015
    Figure PCTCN2020088568-appb-100016
    分别表示稀疏子阵列
    Figure PCTCN2020088568-appb-100017
    在x轴和y轴方向上第i 1和i 2个物理天线阵元的实际位置,且
    Figure PCTCN2020088568-appb-100018
    Figure PCTCN2020088568-appb-100019
    每个块采样范围内,稀疏子阵列
    Figure PCTCN2020088568-appb-100020
    的接收信号可用另一个三维张量
    Figure PCTCN2020088568-appb-100021
    表示为:
    Figure PCTCN2020088568-appb-100022
    其中,
    Figure PCTCN2020088568-appb-100023
    为与各信号源相互独立的噪声张量,
    Figure PCTCN2020088568-appb-100024
    Figure PCTCN2020088568-appb-100025
    分别为稀疏子阵列
    Figure PCTCN2020088568-appb-100026
    在x轴和y轴方向上的导引矢量,对应于来波方向为
    Figure PCTCN2020088568-appb-100027
    的信号源,表示为:
    Figure PCTCN2020088568-appb-100028
    Figure PCTCN2020088568-appb-100029
    其中,
    Figure PCTCN2020088568-appb-100030
    Figure PCTCN2020088568-appb-100031
    分别表示稀疏子阵列
    Figure PCTCN2020088568-appb-100032
    在x轴和y轴方向上第i 3和i 4个物理天线阵元的实际位置,且
    Figure PCTCN2020088568-appb-100033
    对于一个块采样T r(r=1,2,…,R),计算该块采样范围内子阵列
    Figure PCTCN2020088568-appb-100034
    Figure PCTCN2020088568-appb-100035
    的接收张量信号
    Figure PCTCN2020088568-appb-100036
    Figure PCTCN2020088568-appb-100037
    的二阶互相关张量
    Figure PCTCN2020088568-appb-100038
    表示为:
    Figure PCTCN2020088568-appb-100039
    这里,
    Figure PCTCN2020088568-appb-100040
    Figure PCTCN2020088568-appb-100041
    分别表示
    Figure PCTCN2020088568-appb-100042
    Figure PCTCN2020088568-appb-100043
    在第三维度(即快拍维度)方向上的第l个切片,(·) *表示共轭操作;
    (3)由互相关张量
    Figure PCTCN2020088568-appb-100044
    得到一个增广的非均匀虚拟域面阵
    Figure PCTCN2020088568-appb-100045
    其中各虚拟阵元的位置表示为:
    Figure PCTCN2020088568-appb-100046
    其中,单位间隔d取为入射窄带信号波长λ的一半,即d=λ/2。定义维度集合
    Figure PCTCN2020088568-appb-100047
    Figure PCTCN2020088568-appb-100048
    则通过对互相关张量
    Figure PCTCN2020088568-appb-100049
    的理想值
    Figure PCTCN2020088568-appb-100050
    (无噪声场景)进行PARAFAC分解的模
    Figure PCTCN2020088568-appb-100051
    展开,可获得增广虚拟域面阵
    Figure PCTCN2020088568-appb-100052
    的等价接收信号
    Figure PCTCN2020088568-appb-100053
    的理想表示为:
    Figure PCTCN2020088568-appb-100054
    其中,
    Figure PCTCN2020088568-appb-100055
    Figure PCTCN2020088568-appb-100056
    Figure PCTCN2020088568-appb-100057
    是增广虚拟域面阵
    Figure PCTCN2020088568-appb-100058
    在x轴和y轴方向上的导引矢量,对应于来波方 向为
    Figure PCTCN2020088568-appb-100059
    的信号源;
    Figure PCTCN2020088568-appb-100060
    表示第k个入射信号源的功率;这里,
    Figure PCTCN2020088568-appb-100061
    表示克罗内克积;张量下标表示张量PARAFAC分解的模展开操作;
    (4)
    Figure PCTCN2020088568-appb-100062
    中包含一个x轴分布为(-N x+1)d到(M xN x+M x-1)d、y轴分布为(-N y+1)d到(M yN y+M y-1)d的连续均匀虚拟域面阵
    Figure PCTCN2020088568-appb-100063
    中共有V x×V y个虚拟阵元,其中V x=M xN x+M x+N x-1,V y=M yN y+M y+N y-1,
    Figure PCTCN2020088568-appb-100064
    表示为:
    Figure PCTCN2020088568-appb-100065
    通过选取虚拟域等价接收信号U r中与
    Figure PCTCN2020088568-appb-100066
    各虚拟阵元位置相对应的元素,获取虚拟域均匀面阵
    Figure PCTCN2020088568-appb-100067
    的块采样等价接收信号
    Figure PCTCN2020088568-appb-100068
    将其表示为:
    Figure PCTCN2020088568-appb-100069
    其中,
    Figure PCTCN2020088568-appb-100070
    Figure PCTCN2020088568-appb-100071
    Figure PCTCN2020088568-appb-100072
    Figure PCTCN2020088568-appb-100073
    为虚拟域均匀面阵
    Figure PCTCN2020088568-appb-100074
    在x轴和y轴方向上的导引矢量,对应于来波方向为
    Figure PCTCN2020088568-appb-100075
    的信号源;
    (5)按照前述步骤,取R个块采样T r(r=1,2,…,R)对应得到R个虚拟域信号
    Figure PCTCN2020088568-appb-100076
    将这R个虚拟域信号
    Figure PCTCN2020088568-appb-100077
    在第三维度上进行叠加,得到一个第三维度表示等效采样时间信息的虚拟域张量信号
    Figure PCTCN2020088568-appb-100078
    求块采样虚拟域张量信号
    Figure PCTCN2020088568-appb-100079
    的四阶自相关张量
    Figure PCTCN2020088568-appb-100080
    将其表示为:
    Figure PCTCN2020088568-appb-100081
    其中,
    Figure PCTCN2020088568-appb-100082
    表示
    Figure PCTCN2020088568-appb-100083
    在第三维度(即通过块采样所表征的等效采样时间序列信息维度)方向上的第r个切片;
    (6)对虚拟域四阶自相关张量
    Figure PCTCN2020088568-appb-100084
    进行CANDECOMP/PARACFAC分解以提取多维特征,得到结果表示如下:
    Figure PCTCN2020088568-appb-100085
    其中,
    Figure PCTCN2020088568-appb-100086
    Figure PCTCN2020088568-appb-100087
    为CANDECOMP/PARACFAC分解得到的因子矢量,分别表示x轴方向空间信息和y轴方向空间信息;此时,自相关张量
    Figure PCTCN2020088568-appb-100088
    CANDECOMP/PARACFAC分解可分辨的信源个数K的理论最大值,超过实际物理阵元个数;进一步地,构造信号子空间
    Figure PCTCN2020088568-appb-100089
    将其表示为:
    Figure PCTCN2020088568-appb-100090
    其中,orth(·)表示矩阵正交化操作;进一步地,用
    Figure PCTCN2020088568-appb-100091
    表示噪声子空间,则
    Figure PCTCN2020088568-appb-100092
    Figure PCTCN2020088568-appb-100093
    存在以下关系:
    Figure PCTCN2020088568-appb-100094
    其中,I表示单位矩阵;(·) H表示共轭转置操作;
    (7)根据得到的信号子空间和噪声子空间,构造自由度增强的张量空间谱函数,得到对应二维波达方向的空间谱估计。
  2. 根据权利要求1所述的基于平面互质阵列块采样信号构造的自由度增强型空间谱估计方法,其特征在于,步骤(1)所述的互质面阵结构可描述为:在平面坐标系xoy上构造一对稀疏均匀平面子阵列
    Figure PCTCN2020088568-appb-100095
    Figure PCTCN2020088568-appb-100096
    其中
    Figure PCTCN2020088568-appb-100097
    包含2M x×2M y个天线阵元,在x轴方向上和y轴方向上的阵元间距分别为N xd和N yd,其在xoy上的位置坐标为{(N xdm x,N ydm y),m x=0,1,...,2M x-1,m y=0,1,...,2M y-1};
    Figure PCTCN2020088568-appb-100098
    包含N x×N y个天线阵元,在x轴方向上和y轴方向上的阵元间距分别为M xd和M yd,其在xoy上的位置坐标为{(M xdn x,M ydn y),n x=0,1,...,N x-1,n y=0,1,...,N y-1};这里,M x、N x以及M y、N y分别为一对互质整数,且M x<N x,M y<N y;将
    Figure PCTCN2020088568-appb-100099
    Figure PCTCN2020088568-appb-100100
    按照(0,0)坐标处阵元重叠的方式进行子阵列组合,获得实际包含4M xM y+N xN y-1个物理天线阵元的互质面阵。
  3. 根据权利要求1所述的基于平面互质阵列块采样信号构造的自由度增强型空间谱估计方法,其特征在于,步骤(3)所述的互相关张量
    Figure PCTCN2020088568-appb-100101
    可理想(无噪声 场景)建模为:
    Figure PCTCN2020088568-appb-100102
    此时,
    Figure PCTCN2020088568-appb-100103
    Figure PCTCN2020088568-appb-100104
    等价于沿着x轴的一个增广虚拟域,
    Figure PCTCN2020088568-appb-100105
    等价于沿着y轴的一个增广虚拟域,从而可以得到非均匀虚拟域面阵
    Figure PCTCN2020088568-appb-100106
  4. 根据权利要求1所述的基于平面互质阵列块采样张量信号构造的自由度增强型空间谱估计方法,其特征在于,步骤(5)所述的构造对应R个块采样T r(r=1,2,…,R)的虚拟域等价信号
    Figure PCTCN2020088568-appb-100107
    Figure PCTCN2020088568-appb-100108
    沿着第三个维度进行叠加得到虚拟域张量信号
    Figure PCTCN2020088568-appb-100109
    该虚拟域张量信号
    Figure PCTCN2020088568-appb-100110
    的前两个维度分别表征虚拟域均匀面阵在x轴和y轴方向上的空间信息,第三个维度表征通过块采样构造的等效采样时间序列信息,虚拟域张量信号
    Figure PCTCN2020088568-appb-100111
    与平面互质阵列的实际接收张量信号
    Figure PCTCN2020088568-appb-100112
    Figure PCTCN2020088568-appb-100113
    具有相同结构,可以对虚拟域张量信号
    Figure PCTCN2020088568-appb-100114
    直接求其四阶自相关张量,而不需要引入空间平滑过程来弥补单块拍虚拟域信号带来的秩亏问题。
  5. 根据权利要求1所述的基于平面互质阵列块采样张量信号构造的自由度增强型空间谱估计方法,其特征在于,步骤(6)所述的四阶自相关张量
    Figure PCTCN2020088568-appb-100115
    的CANDECOMP/PARACFAC分解遵循唯一性条件如下:
    Figure PCTCN2020088568-appb-100116
    其中,
    Figure PCTCN2020088568-appb-100117
    表示矩阵的Kruskal秩,
    Figure PCTCN2020088568-appb-100118
    Figure PCTCN2020088568-appb-100119
    Figure PCTCN2020088568-appb-100120
    表示因子矩阵,且
    Figure PCTCN2020088568-appb-100121
    Figure PCTCN2020088568-appb-100122
    min(·)表示取最小值操作;因此该CANDECOMP/PARACFAC分解唯一性条件转化为:
    2 min(V x,K)+2min(V y,K)≥2K+3,
    根据上述不等式,可分辨信源个数K大于实际物理阵元个数,K的最大值为
    Figure PCTCN2020088568-appb-100123
    表示取整操作。
  6. 根据权利要求1所述的基于平面互质阵列块采样张量信号构造的自由度增强型空间谱估计方法,其特征在于,步骤(7)中利用虚拟域四阶自相关张量CANDECOMP/PARACFAC分解得到的信号和噪声子空间构建张量空间谱函数,首先定义用于谱峰搜索的二维波达方向
    Figure PCTCN2020088568-appb-100124
    并构造对应虚拟域均匀面阵
    Figure PCTCN2020088568-appb-100125
    的导引信息
    Figure PCTCN2020088568-appb-100126
    表示为:
    Figure PCTCN2020088568-appb-100127
    基于噪声子空间的张量空间谱函数
    Figure PCTCN2020088568-appb-100128
    表示如下:
    Figure PCTCN2020088568-appb-100129
    由此,得到对应二维搜索波达方向
    Figure PCTCN2020088568-appb-100130
    的自由度增强型张量空间谱。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113359086A (zh) * 2021-06-25 2021-09-07 南京航空航天大学 基于增广互质阵列的加权子空间数据融合直接定位方法

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021068496A1 (zh) * 2020-05-03 2021-04-15 浙江大学 基于结构化虚拟域张量信号处理的互质面阵二维波达方向估计方法
CN112904272B (zh) * 2021-01-18 2022-02-18 浙江大学 基于互相关张量的三维互质立方阵列波达方向估计方法
CN114092817B (zh) * 2021-12-14 2022-04-01 深圳致星科技有限公司 目标检测方法、存储介质、电子设备及目标检测装置

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160091598A1 (en) * 2014-09-26 2016-03-31 The Govemment of the United States of America, as represented by the Secretary of the Navy Sparse Space-Time Adaptive Array Architecture
CN107611624A (zh) * 2017-08-24 2018-01-19 电子科技大学 低旁瓣的基于互质思想的分子阵布阵方法
CN108710102A (zh) * 2018-05-15 2018-10-26 浙江大学 基于互质阵列二阶等价虚拟信号离散傅里叶逆变换的波达方向估计方法
CN109471086A (zh) * 2018-10-18 2019-03-15 浙江大学 基于多采样快拍和集阵列信号离散傅里叶变换的互质mimo雷达波达方向估计方法
CN110133576A (zh) * 2019-05-23 2019-08-16 成都理工大学 基于级联残差网络的双基互质mimo阵列方位估计算法

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2017116425A (ja) 2015-12-24 2017-06-29 学校法人東京電機大学 Mimoレーダシステム、および信号処理装置
CN107037392B (zh) 2017-03-01 2020-08-07 浙江大学 一种基于压缩感知的自由度增加型互质阵列波达方向估计方法
CN110927661A (zh) 2019-11-22 2020-03-27 重庆邮电大学 基于music算法的单基地展开互质阵列mimo雷达doa估计方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160091598A1 (en) * 2014-09-26 2016-03-31 The Govemment of the United States of America, as represented by the Secretary of the Navy Sparse Space-Time Adaptive Array Architecture
CN107611624A (zh) * 2017-08-24 2018-01-19 电子科技大学 低旁瓣的基于互质思想的分子阵布阵方法
CN108710102A (zh) * 2018-05-15 2018-10-26 浙江大学 基于互质阵列二阶等价虚拟信号离散傅里叶逆变换的波达方向估计方法
CN109471086A (zh) * 2018-10-18 2019-03-15 浙江大学 基于多采样快拍和集阵列信号离散傅里叶变换的互质mimo雷达波达方向估计方法
CN110133576A (zh) * 2019-05-23 2019-08-16 成都理工大学 基于级联残差网络的双基互质mimo阵列方位估计算法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
GUI YUFENG, RAO WEI: "Two-dimensional coprime vector-sensor array signal processing based on tensor decompositions", JOURNAL OF NANCHANG INSTITUTE OF TECHNOLOGY, vol. 38, no. 4, 1 August 2019 (2019-08-01), pages 83 - 91, XP055800302 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113359086A (zh) * 2021-06-25 2021-09-07 南京航空航天大学 基于增广互质阵列的加权子空间数据融合直接定位方法
CN113359086B (zh) * 2021-06-25 2023-05-12 南京航空航天大学 基于增广互质阵列的加权子空间数据融合直接定位方法

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