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1.
基于ESPRIT宽带信号测向技术研究   总被引:1,自引:1,他引:0  
研究了基于ESPRIT宽带信号测向技术,采用信号子空间变换方法分别对2个平移矩阵聚焦处理,并利用窄带ESPRIT测向方法计算出来波方向,提出利用ESPRIT与聚焦处理相结合测向的方法,解决了ESPRIT宽带信号测向精度差问题。通过聚焦处理有效抑制噪声,提高信噪比,从而获得高精度、高分辨率的渐进无偏估计信号方向。计算机仿真验证了算法的有效性。  相似文献   

2.
一种基于ESPRIT的改进算法   总被引:2,自引:0,他引:2  
在目标波达方向估计的众多算法中,ESPRIT算法是一种运算速度较快、估值精度较高的常用算法.在该算法中,利用两个相同平移阵列接收信号的协方差矩阵进行广义特征值分解,进而求出目标波达方向的高分辨率估计,但是由于需要对协方差矩阵进行广义特征值分解运算,大大增加了计算的复杂度,因而不利于在工程应用中实现.本文提出了一种基于ESPRIT的改进算法,不需要对来波信号的协方差矩阵进行广义特征值分解,就可以实现对目标波达方向的高分辨估计,理论分析和仿真结果证明了该改进算法的有效性和可行性.  相似文献   

3.
把经典的波达方向估计算法应用于均匀圆阵智能天线是一个重要的研究课题。通过预处理技术把均匀圆阵转换成虚拟均匀线阵,为了解决噪声造成信号子空间的扰动问题,提出了两种总体最小二乘ESPRIT(TLS—ESPRIT);为把ESPRIT算法应用于均匀圆阵,引入了模式空间的ESPRIT算法。通过建立恰当的数学模型,对上述各算法的均匀线阵和均匀圆阵上的性能进行仿真和对比分析。仿真结果证明,两种改进的算法性能均好于基本的ESPRIT算法。  相似文献   

4.
一种基于L阵的二维解相干测向算法   总被引:1,自引:0,他引:1  
本文对高斯白噪声环境下基于L型阵列二维测向的ESPRIT算法进行了改进.该算法利用阵列结构特点通过平滑原理获得3个互相关矩阵,然后由3个矩阵构造一个特殊大矩阵并对其进行奇异值分解来估计信号子空间,最后利用2D-ESPRIT方法实现二维测向.该算法估计精度高,运算量小,能够对相干信号进行估计.  相似文献   

5.
一种不考虑信源数目的修正MUSIC算法   总被引:1,自引:0,他引:1  
分析了信源数目估计误差下的MUSIC算法性能.为了解决信源数目过估计下出现虚假信号和欠估计下谱峰消失的问题,提出了一种改进算法.该算法通过对采样数据的共轭重排再利用,重新构造相关矩阵来改善测向性能.改进的算法不仅能成功运用于非相关信号源和相关信号源,还具有不用考虑信源数目的优点.计算机仿真结果证明了改进算法的正确性和有效性.  相似文献   

6.
针对阵列天线的波达方向估计问题,给出了一种新颖的ESPRIT算法--共轭ESPRIT算法(C-ESPRIT).此算法利用阵列单元输出信号的共轭信息,得到整个阵列输出的协方差矩阵,通过对此矩阵的特征分解,并构造运算矩阵,最终求得信号的波达方向.仿真实验表明,C-ESPRIT算法不仅克服了传统ESPRIT算法在阵列单元数与信源数相同时不能可靠测向的不足,并且对信号波达方向的分辨能力和测角精度也显著高于传统的ESPRIT算法,因此,C-ESPRIT算法具有更广泛的适应性和更优越的测向性能.  相似文献   

7.
为了解决酉旋转不变子空间波束赋形算法在低信噪比环境下性能急剧下降的问题,提出了基于小波变换的酉ESPRIT算法。该算法在分析运算特点后有效调整运算顺序以控制计算量,利用小波变换去噪原理,能在低信噪比及阵元数有限的条件下正确估计来波方向。仿真结果表明,与传统ESPRIT算法及酉ESPRIT算法相比,该算法在低信噪比且不增加阵元数的情况下能更加准确地分辨来波方向。  相似文献   

8.
利用两次奇异值分解实现二维ESPRIT参量配对   总被引:10,自引:0,他引:10  
范达  张莉  吴瑛 《通信学报》2002,23(11):80-85
本文主要讲述了一种ESPRIT的改进算法,该算法利用两次奇异值及一次SCHUR分解从而实现对ESPRIT各维估计参量的配对。该方法采用了二排均匀直线阵并附加一阵元,以此来对阵列进行两次子阵分解。利用子阵信号数据矩阵中包含的信号空间的旋转不变性质,借助于矩阵束方法求解出信号的二维到达角,仿真结果证实了该算法的有效性。  相似文献   

9.
卫星信号的盲测向是使用阵列天线进行导航终端抗干扰的基础,为了解决该问题,文中利用每颗卫星对应C/A码的唯一性进行解扩,提高了卫星导航信号的信噪比,采用多级维纳滤波分解得到的信号子空间代替ESPRIT算法中特征分解得到的信号子空间,提出一种基于多级维纳滤波的ESPRIT算法来实现卫星导航信号测向的应用.仿真结果表明,该算法不但能够实现卫星导航弱信号的测向,而且能够降低ESPRIT算法的运算量,具有更好的稳健性和测向性能.  相似文献   

10.
MUSIC算法,即多信号分类算法,常用于同频信号测向系统,主要利用信号分量相对应的信号子空间和信号分量正交的噪声子空间的正交性来对信源进行估计计算。在实际测向过程中,信号子空间和噪声子空间并不能实现完全正交,并且测试环境引入噪声干扰,对测向结果都构成影响。基于以上问题,对MUSIC算法进行了改进,加入了两种谱线改进算法,分别是谱线增强算法和谱二阶算法;通过对信号进行谱线增强,提高信号的信噪比,并在信号测向过程中加入二阶导数识别算法、提高信号测向角度识别率等方法,能够有效提高信号的信噪比和抗干扰性,增强了测向算法的识别率和精准度。  相似文献   

11.
基于数据共轭重排的修正ESPRIT信号DOA估计算法   总被引:3,自引:0,他引:3  
本文介绍了将接收数据共轭重排的再利用,构造相关矩阵的修正ESPRIT算法.理论分析和仿真实验表明,该算法同经典的ESPRIT算法相比,在快拍次数有限时,可明显改善信号DOA估计的性能,且其计算量二者基本相当.  相似文献   

12.
该文提出了一种基于QR分解的Power-ESPRIT(以下简称QP-ESPRIT算法)新算法.首先使用采样数据协方差矩阵的幂(Power)获得噪声子空间的估计,然后对噪声子空间进行QR分解并使用R矩阵估计信源个数,提出了无特征分解的信源个数检测算法--SDWED算法.进而,信号子空间的特征向量就可以由Q矩阵确定,从而应用ESPRIT算法获得信源波达方向的估计.该算法不需要预先知道信源个数的先验知识以及分离信号与噪声特征值的门限.在确定信源个数和子空间估计的同时,本文算法与传统的基于奇异值分解算法相比,具有近似性能时却拥有较低的计算复杂度.仿真结果证明了该方法的有效性.  相似文献   

13.
In this paper,a low complexity ESPRIT algorithm based on power method and Orthogo- nal-triangular (QR) decomposition is presented for direction finding,which does not require a priori knowledge of source number and the predetermined threshold (separates the signal and noise ei- gen-values).Firstly,according to the estimation of noise subspace obtained by the power method,a novel source number detection method without eigen-decomposition is proposed based on QR de- composition.Furthermore,the eigenvectors of signal subspace can be determined according to Q matrix and then the directions of signals could be computed by the ESPRIT algorithm.To determine the source number and subspace,the computation complexity of the proposed algorithm is approximated as (2log_2 n 2.67)M~3,where n is the power of covariance matrix and M is the number of array ele- ments.Compared with the Single Vector Decomposition (SVD) based algorithm,it has a substantial computational saving with the approximation performance.The simulation results demonstrate its effectiveness and robustness.  相似文献   

14.
Direction-of-arrival estimation for constant modulus signals   总被引:5,自引:0,他引:5  
In many cases where direction finding is of interest, the signals impinging on an antenna array are known to be phase modulated and, hence, to have a constant modulus (CM). This is a strong property; by itself, it is already sufficient for source separation and can be used to construct improved direction finding algorithms. We first derive the relevant Cramer-Rao bounds (CRBs) for arbitrary array configurations and specialize to uniform linear arrays. We then propose a simple suboptimal direction estimation algorithm in which the signals are separated using the CM property followed by direction finding on the decoupled signals. Compared with the ESPRIT algorithm and the CRB for arbitrary signals, the algorithm shows good results  相似文献   

15.
Beamspace ESPRIT   总被引:9,自引:0,他引:9  
Most high-resolution algorithms for sensor array processing require an eigendecomposition, which is a computation that is difficult to implement in parallel and requires O(M3) multiplications for an M×M matrix, corresponding to M sensors. Beamspace transformation is one way of reducing computation and sometimes improving the estimation accuracy. As a consequence of the beamspace transformation performed, however, arrays such as uniform linear arrays commonly used in direction finding lose their displacement invariance structure. As a result, computational complexity may actually increase since the computationally efficient ESPRIT algorithm cannot be applied directly. In this paper, a method for restoring the invariance structure resulting in a beamspace ESPRIT algorithm is described. Asymptotic performance analysis of beamspace ESPRIT and simulation results are presented as well  相似文献   

16.
提出了一种新颖的解相关同步CDMA系统二维(方位/高低)波达方向(DOA)估计算法,通过解相关处理,可通过两次运用一维ESPRIT算法解决相应的二维方位/高低波达方向的估计问题,仿真结果表明本算法能有效,精确地解决信号的二维DOA估计问题。  相似文献   

17.
Genetic algorithm (GA)-based direction of arrival (DOA) estimation is proposed using fourth-order cumulants (FOC) and ESPRIT principle which results in Multiple Invariance Cumulant ESPRIT algorithm. In the existing FOC ESPRIT formulations, only one invariance is utilised to estimate DOAs. The unused multiple invariances (MIs) must be exploited simultaneously in order to improve the estimation accuracy. In this paper, a fitness function based on a carefully designed cumulant matrix is developed which incorporates MIs present in the sensor array. Better DOA estimation can be achieved by minimising this fitness function. Moreover, the effectiveness of Newton’s method as well as GA for this optimisation problem has been illustrated. Simulation results show that the proposed algorithm provides improved estimation accuracy compared to existing algorithms, especially in the case of low SNR, less number of snapshots, closely spaced sources and high signal and noise correlation. Moreover, it is observed that the optimisation using Newton’s method is more likely to converge to false local optima resulting in erroneous results. However, GA-based optimisation has been found attractive due to its global optimisation capability.  相似文献   

18.
In this paper, we study the problem of four-dimensional angle estimation for bistatic multiple-input multiple-output (MIMO) radar with arbitrary arrays, and propose a close-form joint two-dimensional direction of departure and two-dimensional direction of arrival estimation algorithm. Our work is to extend the estimation of signal parameters via rotational invariance techniques (ESPRIT) algorithm to angle estimation in MIMO-radar with arbitrary arrays. The algorithm can achieve automatically paired four-dimensional angles, requires no peak searching, has low complexity, and does not need to compensate for the phase. Furthermore, the proposed algorithm has much better angle estimation performance than the interpolated ESPRIT algorithm and propagator method. We also analyze and derive the complexity of the algorithm and the Cramer–Rao bound. The simulation results verify the effectiveness of the algorithm.  相似文献   

19.
影响DOA精度因素的研究   总被引:1,自引:0,他引:1  
杨丽娜 《现代雷达》2007,29(6):70-73
在信号DOA估计中,基于子空间旋转不变性的TLS-ESPRIT算法深受欢迎。文中首先介绍了TLS-ESPRIT算法并简要的对该算法进行分析。同时针对空间存在单信号和多信号两种情况,分析了影响TLS-ESPRIT算法精度的因素,主要讨论了入射角大小和空间存在多信号源对算法估计精度的影响,在计算机上进行了仿真研究,并得出结论。同时给出了提高TLS-ESPRIT算法适用范围,减小误差的有效方法。  相似文献   

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