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针对非零均值乘性噪声中的谐波恢复问题,本文提出一种基于广义协方差矩阵的乘性噪声中谐波个数和频率的估计方法。首先定义一类广义协方差并构造广义协方差矩阵,通过对广义协方差矩阵进行特征值理论分析,得到了非零均值乘性噪声中谐波分量个数与协方差矩阵特征值之间的内在联系,这个性质可以用来估计谐波分量个数。而且利用子空间旋转不变性技术,可以从协方差矩阵中估计出谐波的频率。本文所提方法对于乘性和加性噪声的颜色和分布均无任何假设,可以应用于任意分布和任意颜色的乘性和加性噪声中的谐波恢复。仿真实验表明,本文所提谐波恢复方法具有很高的频率分辨率。 相似文献
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噪声中的谐波恢复问题是信号处理领域的一个典型问题,在众多领域中有着广泛的应用。本文主要研究零均值乘性和加性噪声并存下的二维谐波信号频率估计问题,提出了一种基于数据矩阵的奇异值分解和子空间的旋转不变性的零均值乘性和加性噪声中的谐波频率的估计方法。乘性噪声为零均值情形下传统的估计方法往往难以直接应用或估计失效。本文利用谐波模型信号特征,通过对观测信号进行平方运算构造了一个数据矩阵。通过对数据矩阵的特征值进行理论分析,结合子空间旋转不变性,得到了零均值乘性和加性噪声中的谐波频率和数据矩阵之间的一种内在关系。这个性质可以用于零均值乘性和加性噪声并存下的二维谐波信号频率估计,并且所得的二维频率能自动配对。仿真实验验证了本文所提算法的有效性。 相似文献
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非高斯有色噪声中谐波恢复的累积量投影方法 总被引:3,自引:0,他引:3
本文研究非高斯有色噪声中的谐波恢复问题。首先建立了复数线性非高斯过程的高阶累积量投影定理。应用该定理,由含噪谐波信号的四阶累积量求得非高斯有色噪声的自相关,然后通过求解一个广义特征值问题对矢量空间进行预白化,最后结合噪声子空间方法MUSIC恢复谐波信号参数。本文方法克服了以往的困难,成功地解决了对称分布非高斯噪声背景下和谐波信号中存在二次相位耦合时的谐波恢复问题。仿真实验验证了本文结论。 相似文献
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利用加权平滑l0范数(Smoothed l0, SL0)算法估计MIMO雷达目标DOA时,需要把协方差矩阵进行矢量化来获得相应的稀疏重构模型,并利用信号和噪声子空间的正交性来构造加权向量。然而当存在相干信源时,MIMO雷达协方差矩阵的秩将退化,这会使得稀疏重构模型的误差较大以及无法正确区分信号和噪声子空间,导致加权SL0算法的DOA估计性能恶化。针对上述问题提出了一种基于协方差匹配SL0算法的MIMO雷达DOA估计方法。该方法利用协方差匹配准则重构出一个满秩的协方差矩阵,恢复MIMO雷达协方差矩阵的Toeplitz特性,并利用协方差逆矩阵的高阶幂来近似噪声子空间从而计算加权向量。仿真分析表明,该方法能够在无需预知信源数目的情况下有效地完成对相干信号的DOA估计。 相似文献
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针对有色噪声背景下的不相关和相干混合入射信号,本文提出了一种新的波达角度(Direction Of Arrival,DOA)估计方法 .首先对混合信号协方差矩阵进行分析和处理以消除其中的有色噪声部分.在此基础上,先利用多重信号分类(Multiple Signal Classification,MUSIC)方法或旋转不变信号参数估计(Estimation of Signal Parameters via Rotational Invariance Techniques,ESPRIT)法估计出不相关信号的DOA;然后利用改进的空间差分方法构造出一个新的只含有相干信号的协方差矩阵,且无秩亏损;最后利用MUSIC算法或ESPRIT算法从中估计出相干信号的DOA.和文献报道的方法相比,新方法具有更优的混合信号DOA估计性能,尤其对于相干信号.仿真结果验证了该算法的有效性. 相似文献
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基于Hamilton四元数矩阵奇异值分解的二维谐波频率参量估计 总被引:2,自引:0,他引:2
对于二维谐波信号的四元数模型,首先论述其与二维谐波的实数模型和复数模型之间的对应与转换关系,之后提出运用四元数矩阵奇异值分解估计二维谐波中频率参量的算法.这种算法首先可以利用四元数矩阵的奇异值判断出原始的二维谐波信号个数,然后再分别利用四元数矩阵的左、右奇异向量中的噪声向量构造的噪声子空间估计出两维的谐波频率参量.算法本身需要的数据量少,数据矩阵构造简单,并且可以同时估计出两维谐波频率参量.从仿真实验中可以看出,本文提出的算法计算量相对其它针对二维谐波四元数模型的算法要小.仿真实验验证了本文算法的正确性. 相似文献
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This paper proposes a novel method to detect the number of two‐dimensional (2D) harmonics in additive colored noise based on the enhanced covariance matrix. We define an enhanced covariance matrix using the covariances of the observed signal. We get a special inherent relation between the number of 2D harmonics in additive colored noise and the eigenvalues of the enhanced covariance matrix, which can be used to detect the number of 2D harmonics in additive colored noise by analyzing the eigenvalues of the enhanced covariance matrix. The proposed method has a super resolution and does not need to assume the color and distribution of the additive noise. The effectiveness of the proposed method has been validated by both the theoretical analysis and extensive simulations. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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A frequently encountered problem in signal processing is harmonic retrieval in additive colored Gaussian or non-Gaussian noise,
especially when the frequencies of the harmonic signals are very close in space. The purpose of this paper is to develop an
efficient Blind Source Separation (BSS) algorithm from linear mixtures of source signals, which enables to separate harmonic
source signals using only one observed channel signal even if the frequencies of the harmonic signals are closely spaced.
First, we establish the BSS based harmonic retrieval model in additive noise by using the only one observed channel, and analyze
the fundamental principle by utilizing BSS method to retrieve harmonics. Then, we propose a BSS-based approach to the harmonic
retrieval by resorting the concept of W-disjoint orthogonality in the over-complete BSS situation, and as a result, we get
the separation algorithm using only one channel mixed signals. Simulation results show that the proposed separation algorithm-BSS-HR
is able to separate the harmonic source signals. 相似文献
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A frequently encountered problem in signal processing is that of estimating the frequencies and amplitudes of harmonics observed in additive colored Gaussian noise. In practice, the observed signals are contaminated with spatially and temporally colored noise of unknown power spectral density. A cumulant-based approach to these problems is proposed. The cumulants of complex processes are defined, and it is shown that specific 1-D slices of the fourth-order cumulant of the noisy signal for the direction of arrival (DOA) and retrieval of harmonics in noise (RHN) problems are identical to the autocorrelation of a related noiseless signal. Hence correlation-based high-resolution methods may be used with fourth-order cumulants as well. The effectiveness of the proposed methods is demonstrated through standard simulation examples 相似文献
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WANG Fei WANG Shu-xun WU Yong-guiInstitution of Communication Engineering Jilin University Changchun P.R.China 《中国邮电高校学报(英文版)》2005,12(3)
1 Introduction In many applications ,such as radar ,sonar and com-munication, parameters esti mation of two di mensionalharmonics was veryi mportant .In order to get highres-olutions esti mation, many subspace methods of one di-mensional harmonics , such as MUSIC, MEMP,ES-PRIT, have been developed to esti mate parameters oftwo di mensional harmonics[1 ~3]. When additive noise was colored Gaussian noiseH.M.ibrahi m[4]and R. R. Gharieb[5]analyzed thisproblem with high-order cumulants sin… 相似文献
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Harmonic retrieval in colored non-Gaussian noise using cumulants 总被引:1,自引:0,他引:1
Yan Zhang Shu-Xun Wang 《Signal Processing, IEEE Transactions on》2000,48(4):982-987
This paper addresses the harmonic retrieval problem in colored linear non-Gaussian noise of unknown covariance and unknown distribution. The assumptions made in the reported studies that the non-Gaussian noise is asymmetrically distributed and no quadratic phase coupling occurs are released. Using the elaborately defined fourth-order cumulants of the complex noisy observations, which are obtained by Hilbert transform, we can estimate either the correlation or the AR polynomial of the non-Gaussian noise via cumulant projections or ARMA modeling; then, the prewhitening or prefiltering techniques can be employed to retrieve harmonics, respectively. Simulation results are presented to demonstrate the effectiveness of the proposed algorithms 相似文献
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Xian-Da Zhang Ying-Chang Liang Yan-Da Li 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1994,40(4):1220-1226
Addresses the harmonic retrieval problem in colored noise. As contrasted to the reported studies in which Gaussian noise was assumed, this paper focuses on additive non-Gaussian ARMA noise. Our approach is hybrid in the sense that third-order cumulants are first used to identify the AR part of the non-Gaussian noise process, and then correlation-based high-resolution methods are used for the filtered process to estimate the number of harmonics and their frequencies. Simulation examples are presented to demonstrate the high resolution of this approach 相似文献
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Anderson J.M.M. Giannakis G.B. Swami A. 《Signal Processing, IEEE Transactions on》1995,43(8):1880-1889
Given a single record, the authors consider the problem of estimating the parameters of a harmonic signal buried in noise. The observed data are modeled as a sinusoidal signal plus additive Gaussian noise of unknown covariance. The authors define novel higher order statistics-referred to as “mixed” cumulants-that can be consistently estimated using a single record and are insensitive to colored Gaussian noise. Employing fourth-order mixed cumulants, they estimate the sinusoid parameters using a consistent, nonlinear matching approach. The algorithm requires an initial estimate that is obtained from a consistent, linear estimator. Finally, the authors examine the performance of the proposed method via simulations 相似文献