共查询到19条相似文献,搜索用时 171 毫秒
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根据子空间的基本原理,提出一种新的阵列天线幅相误差校正算法,该方法利用粗略已知的校正源方位角信息进行优化,使用迭代的方法逼近幅相误差的真实值.由于不需要其他的迭代初始值,从而保证该方法能收敛到最优解.计算机仿真实验证明了该方法的有效性. 相似文献
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基于奇异值分解的图像去噪 总被引:3,自引:0,他引:3
提出了利用奇异值分解去除图像噪声的方法。从矩阵的角度出发,通过对图像矩阵进行奇异值分解,将包含图像信息的矩阵分解到一系列奇异值和奇异值矢量对应的子空间中,然后通过有效奇异值重构图像矩阵达到去噪目的。试验利用MATLAB通过对MRI(核磁共振)医学图像进行去噪处理,验证了奇异值分解的去噪效果,并且通过对多幅图像的试验结果进行分析,得到了去噪重构图像时所需有效奇异值数目的统计值。 相似文献
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基于矩阵奇异值分解的高频雷达瞬态干扰抑制 总被引:5,自引:0,他引:5
雷电等瞬态干扰严重影响了高频雷达的工作性能,必须加以抑制。该文提出了基于矩阵奇异值分解的高频雷达瞬态干扰抑制方法。该方法将高频雷达回波信号分段构造成矩阵并进行奇异值分解,首先根据矩阵有效秩的大小判断雷达回波中是否存在瞬态干扰,然后利用奇异值分解的正交性实现雷达回波的正交分解,使瞬态干扰分离出来,以利于检测,最后通过建立线性预测的全极点自回归模型对瞬态干扰位置处的回波信号予以恢复。实测数据处理结果表明该方法是有效的。 相似文献
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雷电等瞬态干扰严重影响了高频雷达的工作性能,必须加以抑制。本文提出了基于矩阵奇异值分解的高频雷达瞬态干扰抑制方法。该方法将高频雷达回波信号分段构造成矩阵并进行奇异值分解,首先根据矩阵有效秩的大小判断雷达回波中是否存在瞬态干扰,然后利用奇异值分解的正交性实现雷达回波的正交分解,使瞬态干扰分离出来,以利于检测,最后通过建立线性预测的全极点AR模型对瞬态干扰位置处的回波信号予以恢复。实测数据处理结果表明本文方法是有效的。 相似文献
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传统的非负矩阵分解方法应用在高光谱像元分解时,混合像元分解用到的初始值是随机产生的,会影响像元的解混效果。为了解决该问题,本文通过改进获得初始值的方法,提出了一种基于改进非负矩阵分解的高光谱图像解混方法。本方法不需要任何先验知识,只需要对输入数据集进行迭代计算得到合适的初始值,即可达到光谱解混的目的。仿真数据和真实数据的实验结果都证明了该算法的有效性。 相似文献
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本文介绍一种外辐射源雷达目标检测中的杂波抑制算法,该算法首先将源自轨道卫星的连续波观测信号重构为观测矩阵,并对观测矩阵进行奇异值分解,利用迭代的方式将大奇异值对应的杂波成分逐渐从观测矩阵中减去,进而实现观测信号中强烈杂波的对消。在杂波消除过程中,最佳迭代阶数由熵变的最小值确定。然后对杂波消除之后的观测矩阵进行相干积累进而实现微弱目标检测。最终的仿真实验结果验证了本文所提方法的有效性和鲁棒性,并且本方法相较于经典的扩展相消算法具备更低的计算量。 相似文献
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In order to appropriately select and adjust response countermeasures,it is necessary to evaluate response effectiveness.Although a large amount of effort has been spent on the evaluation of risk and threat situations,the existing schemes are not suitable to evaluate response effectiveness,because the sechems require that all the information used for evaluation is complete,which is difficult to implement in the real environment.To address the problem,a fuzzy scheme was proposed to deal with incomplete information (i.e.,missing elements of judgment matrix and missing data of indicators) and the response effectiveness was evaluate.Firstly,a hierarchical indicator tree was design to characterize the effectiveness from the perspectives of both attack and defense.Then,the fuzzy analytic hierarchy process (FAHP) was used to calculate the comprehensive weight of each indicator.Finally,the response effectiveness was calculated using fuzzy comprehensive evaluation.In particular,to deal with the problem of incompleteness of fuzzy judgment matrix in the process of FAHP,the missing elements were completed based on the transitivity of elements.And to deal with the problem of loss data in the comprehensive evaluation,the missing data was completed based on matrix completion.The experimental results show that the proposed scheme can accurately recover the missing data and can effectively evaluate the effectiveness of response. 相似文献
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该文提出一种非迭代的稀布线阵方向图综合方法。该方法首先对方向图采样数据进行centro-Hermit化处理,然后通过酉变换构造等价实矩阵束,得到非均匀单元位置与新矩阵束广义特征值的关系。在此基础上,对实矩阵奇异值分解,并舍弃非主要奇异值以获得低阶左奇异向量矩阵,进而求得稀布阵列的阵元位置和相应激励。相比于其他方法,该方法能够直接得到阵元位置的实数解,奇异值分解和特征值分解均在实数域进行,提高逼近程度的同时有效降低了计算量,仿真验证了该方法利用少量阵元即可高效实现线阵的方向图综合。 相似文献
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Recovery of signal with randomly positioned missing samples is a difficult or impossible task. The aim of this paper is to accurately recover missing samples if prior information on domain of sparsity is known. This paper proposes a novel approach for recovery of signals lying in low-dimensional sub-manifold, embedded in high-dimensional signal space and heavily corrupted by arbitrarily positioned missing samples. The proposed simple and efficient algorithm is based on global manifold model and can recover the corrupted signal from the limited available samples without affecting the remaining samples. The proposed method is applicable to any type of data and can be extensively used in a wide variety of data processing techniques. Experimental results prove that the proposed method outperforms the counterparts without much computational complexity. 相似文献
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Jyh-Jong Wei Chuang-Jan Chang Nai-Kuan Chou Gwo-Jen Jan 《IEEE transactions on information technology in biomedicine》2001,5(4):290-299
The method of truncated singular value decomposition (SVD) is proposed for electrocardiogram (ECG) data compression. The signal decomposition capability of SVD is exploited to extract the significant feature components of the ECG by decomposing the ECG into a set of basic patterns with associated scaling factors. The signal information is mostly concentrated within a certain number of singular values with related singular vectors due to the strong interbeat correlation among ECG cycles. Therefore, only the relevant parts of the singular triplets need to be retained as the compressed data for retrieving the original signals. The insignificant overhead can be truncated to eliminate the redundancy of ECG data compression. The Massachusetts Institute of Technology-Beth Israel Hospital arrhythmia database was applied to evaluate the compression performance and recoverability in the retrieved ECG signals. The approximate achievement was presented with an average data rate of 143.2 b/s with a relatively low reconstructed error. These results showed that the truncated SVD method can provide efficient coding with high-compression ratios. The computational efficiency of the SVD method in comparing with other techniques demonstrated the method as an effective technique for ECG data storage or signals transmission 相似文献
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Paris Smaragdis Bhiksha Raj Madhusudana Shashanka 《Journal of Signal Processing Systems》2011,65(3):361-370
With the recent attention towards audio processing in the time-frequency domain we increasingly encounter the problem of missing
data within that representation. In this paper we present an approach that allows us to recover missing values in the time-frequency
domain of audio signals. The presented approach is able to deal with real-world polyphonic signals by operating seamlessly
even in the presence of complex acoustic mixtures. We demonstrate that this approach outperforms generic missing data approaches,
and we present a variety of situations that highlight its utility. 相似文献
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《IEEE transactions on image processing》2009,18(2):435-440
The Landweber scheme is an algebraic reconstruction method and includes several important algorithms as its special cases. The convergence of the Landweber scheme is of both theoretical and practical importance. Using the singular value decomposition (SVD), we derive an iterative representation formula for the Landweber scheme and consequently establish the necessary and sufficient conditions for its convergence. In addition to verifying the necessity and sufficiency of known convergent conditions, we find new convergence conditions allowing relaxation coefficients in an interval not covered by known results. Moreover, it is found that the Landweber scheme can converge within finite iterations when the relaxation coefficients are chosen to be the inverses of squares of the nonzero singular values. Furthermore, the limits of the Landweber scheme in all convergence cases are shown to be the sum of the minimum norm solution of a weighted least-squares problem and an oblique projection of the initial image onto the null space of the system matrix. 相似文献
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应用于缺失数据恢复的迭代自适应方法(IAA)被证实可利用20%的有效数据估计信号参数,并能高精度恢复缺失数据,优于经典GAPES方法,但当缺失数据超过80%时其数据恢复性能迅速下降。该文基于稀疏迭代协方差估计提出一种新的缺失数据谱分析方法(M-SPICE)及针对该方法的缺失数据修正时域重建方法。该方法将加权缺失数据协方差拟合代价函数转换为凸优化问题,构造循环最小化器保证缺失数据参数估计的全局收敛特性,通过对缺失数据估计算子的更新实现了时域重建方法的修正,使其在有效数据功率谱欠估计的情况下获得更高的数据重建精度。仿真实验表明无论是数据块缺失还是任意缺失,该方法均能够利用更少的有效数据进行谱分析,并重建大比例缺失数据。 相似文献
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Reducing the Number of Elements in a Linear Antenna Array by the Matrix Pencil Method 总被引:1,自引:0,他引:1
《Antennas and Propagation, IEEE Transactions on》2008,56(9):2955-2962
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多标签分类已在很多领域得到了实际应用,所用标签大多具有很强的关联性,甚至存在非完备标签或部分标签遗失。然而,现有的多标签分类算法难以同时处理这两种情况。基于此,提出一种新的概率模型处理方法,实现同时对具有标签关联性和遗失标签情况进行多标签分类。该方法可以自动获知和掌握多标签的关联性。此外,通过整合遗失的标签信息,该方法能够提供一个自适应策略来处理遗失的标签。在完备标签和非完备标签的数据上进行实验,结果表明,与现有的多标签分类算法相比,提出的方法得到了较好的分类预测评价值。 相似文献