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Low Complexity Minimum Mean Square Error Channel Estimation for Adaptive Coding and Modulation Systems 被引量:2
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作者 GUO Shuxia SONG Yang +1 位作者 GAO Ying HAN Qianjin 《China Communications》 SCIE CSCD 2014年第1期126-137,共12页
Performance of the Adaptive Coding and Modulation(ACM) strongly depends on the retrieved Channel State Information(CSI),which can be obtained using the channel estimation techniques relying on pilot symbol transmissio... Performance of the Adaptive Coding and Modulation(ACM) strongly depends on the retrieved Channel State Information(CSI),which can be obtained using the channel estimation techniques relying on pilot symbol transmission.Earlier analysis of methods of pilot-aided channel estimation for ACM systems were relatively little.In this paper,we investigate the performance of CSI prediction using the Minimum Mean Square Error(MMSE)channel estimator for an ACM system.To solve the two problems of MMSE:high computational operations and oversimplified assumption,we then propose the Low-Complexity schemes(LC-MMSE and Recursion LC-MMSE(R-LC-MMSE)).Computational complexity and Mean Square Error(MSE) are presented to evaluate the efficiency of the proposed algorithm.Both analysis and numerical results show that LC-MMSE performs close to the wellknown MMSE estimator with much lower complexity and R-LC-MMSE improves the application of MMSE estimation to specific circumstances. 展开更多
关键词 adaptive coding and modulation channel estimation minimum mean square error low-complexity minimum mean square error
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Recursive weighted least squares estimation algorithm based on minimum model error principle 被引量:2
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作者 雷晓云 张志安 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第2期545-558,共14页
Kalman filter is commonly used in data filtering and parameters estimation of nonlinear system,such as projectile's trajectory estimation and control.While there is a drawback that the prior error covariance matri... Kalman filter is commonly used in data filtering and parameters estimation of nonlinear system,such as projectile's trajectory estimation and control.While there is a drawback that the prior error covariance matrix and filter parameters are difficult to be determined,which may result in filtering divergence.As to the problem that the accuracy of state estimation for nonlinear ballistic model strongly depends on its mathematical model,we improve the weighted least squares method(WLSM)with minimum model error principle.Invariant embedding method is adopted to solve the cost function including the model error.With the knowledge of measurement data and measurement error covariance matrix,we use gradient descent algorithm to determine the weighting matrix of model error.The uncertainty and linearization error of model are recursively estimated by the proposed method,thus achieving an online filtering estimation of the observations.Simulation results indicate that the proposed recursive estimation algorithm is insensitive to initial conditions and of good robustness. 展开更多
关键词 minimum model error Weighted least squares method State estimation Invariant embedding method Nonlinear recursive estimate
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Efficient Mean Estimation in Log-normal Linear Models with First-order Correlated Errors
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作者 Zhang Song Wang De-hui 《Communications in Mathematical Research》 CSCD 2013年第3期271-279,共9页
In this paper, we propose a log-normal linear model whose errors are first-order correlated, and suggest a two-stage method for the efficient estimation of the conditional mean of the response variable at the original... In this paper, we propose a log-normal linear model whose errors are first-order correlated, and suggest a two-stage method for the efficient estimation of the conditional mean of the response variable at the original scale. We obtain two estimators which minimize the asymptotic mean squared error (MM) and the asymptotic bias (MB), respectively. Both the estimators are very easy to implement, and simulation studies show that they are perform better. 展开更多
关键词 log-normal first-order correlated maximum likelihood two-stage estimation mean squared error
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Mean Square Error Comparisons of Estimatorsin Two SUR Models
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作者 LIU Jin-shan GUI Qing-ming 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期63-71,共9页
For a system of two seerningly umrelated regressions.some general results of mean square er-ror matrix comparisons are presented.A class of linear estimators and a class of two-stage estimatorsbased on a generalized u... For a system of two seerningly umrelated regressions.some general results of mean square er-ror matrix comparisons are presented.A class of linear estimators and a class of two-stage estimatorsbased on a generalized unrestricted estimate of the dispersion matrix are proposed.Some exact finitesample properties of the two-stage estimators are obtained. 展开更多
关键词 seemingly unrelated regressions two-stage estimator mean square error matrix
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Adaptive Linear Filtering Design with Minimum Symbol Error Probability Criterion 被引量:2
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作者 Sheng Chen 《International Journal of Automation and computing》 EI 2006年第3期291-303,共13页
Adaptive digital filtering has traditionally been developed based on the minimum mean square error (MMSE) criterion and has found ever-increasing applications in communications. This paper presents an alternative ad... Adaptive digital filtering has traditionally been developed based on the minimum mean square error (MMSE) criterion and has found ever-increasing applications in communications. This paper presents an alternative adaptive filtering design based on the minimum symbol error rate (MSER) criterion for communication applications. It is shown that the MSER filtering is smarter, as it exploits the non-Gaussian distribution of filter output effectively. Consequently, it provides significant performance gain in terms of smaller symbol error over the MMSE approach. Adopting Parzen window or kernel density estimation for a probability density function, a block-data gradient adaptive MSER algorithm is derived. A stochastic gradient adaptive MSER algorithm, referred to as the least symbol error rate, is further developed for sample-by-sample adaptive implementation of the MSER filtering. Two applications, involving single-user channel equalization and beamforming assisted receiver, are included to demonstrate the effectiveness and generality of the proposed adaptive MSER filtering approach. 展开更多
关键词 Adaptive filtering mean square error probability density function non-Gaussian distribution Parzen window estimate symbol error rate stochastic gradient algorithm.
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Convolutional Neural Network Auto Encoder Channel Estimation Algorithm in MIMO-OFDM System 被引量:2
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作者 I.Kalphana T.Kesavamurthy 《Computer Systems Science & Engineering》 SCIE EI 2022年第4期171-185,共15页
Higher transmission rate is one of the technological features of promi-nently used wireless communication namely Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing(MIMO–OFDM).One among an effec... Higher transmission rate is one of the technological features of promi-nently used wireless communication namely Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing(MIMO–OFDM).One among an effective solution for channel estimation in wireless communication system,spe-cifically in different environments is Deep Learning(DL)method.This research greatly utilizes channel estimator on the basis of Convolutional Neural Network Auto Encoder(CNNAE)classifier for MIMO-OFDM systems.A CNNAE classi-fier is one among Deep Learning(DL)algorithm,in which video signal is fed as input by allotting significant learnable weights and biases in various aspects/objects for video signal and capable of differentiating from one another.Improved performances are achieved by using CNNAE based channel estimation,in which extension is done for channel selection as well as achieve enhanced performances numerically,when compared with conventional estimators in quite a lot of scenar-ios.Considering reduction in number of parameters involved and re-usability of weights,CNNAE based channel estimation is quite suitable and properlyfits to the video signal.CNNAE classifier weights updation are done with minimized Sig-nal to Noise Ratio(SNR),Bit Error Rate(BER)and Mean Square Error(MSE). 展开更多
关键词 Deep learning channel estimation multiple input multiple output least square linear minimum mean square error and orthogonal frequency division multiplexing
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LMMSE-based SAGE channel estimation and data detection joint algorithm for MIMO-OFDM system 被引量:1
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作者 申京 Wu Muqing 《High Technology Letters》 EI CAS 2012年第2期195-201,共7页
A new channel estimation and data detection joint algorithm is proposed for multi-input multi-output (MIMO) - orthogonal frequency division multiplexing (OFDM) system using linear minimum mean square error (LMMSE... A new channel estimation and data detection joint algorithm is proposed for multi-input multi-output (MIMO) - orthogonal frequency division multiplexing (OFDM) system using linear minimum mean square error (LMMSE)- based space-alternating generalized expectation-maximization (SAGE) algorithm. In the proposed algorithm, every sub-frame of the MIMO-OFDM system is divided into some OFDM sub-blocks and the LMMSE-based SAGE algorithm in each sub-block is used. At the head of each sub-flame, we insert training symbols which are used in the initial estimation at the beginning. Channel estimation of the previous sub-block is applied to the initial estimation in the current sub-block by the maximum-likelihood (ML) detection to update channel estimatjon and data detection by iteration until converge. Then all the sub-blocks can be finished in turn. Simulation results show that the proposed algorithm can improve the bit error rate (BER) performance. 展开更多
关键词 multi-input multi-output (MIMO) orthogonal frequency division multiplexing (OFDM) linear minimum mean square error (LMMSE) space-alternating generalized expectation-maximization (SAGE) ITERATION channel estimation data detection joint algorithm.
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A time domain multiple-CFOs and CIRs estimation algorithm over wireless multimedia sensor networks
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作者 姜建 《High Technology Letters》 EI CAS 2009年第3期294-300,共7页
Channel parameters estimation in an orthogonal for the receiver station is a multi-dimensional (MD) frequency division multiple access (OFDMA) system optimization problem, because every user node has a separate lo... Channel parameters estimation in an orthogonal for the receiver station is a multi-dimensional (MD) frequency division multiple access (OFDMA) system optimization problem, because every user node has a separate local oscillator and every transmitter to receiver link has individual carrier frequency offset (CFO) and channel impulse response (CIR) parameters. In order to reduce the computational complexity for MD optimization, a time domain CFOs and CIRs estimation algorithm over the OFDMA based wireless multimedia sensor networks (WMSN) is proposed in this paper. In this algorithm, the receiver station can decouple the signal from every node by correlation based on specially designed training sequences, so that the MD optimization problem is simplified to an 1-D optimal problem. It is proved that the multiple CFOs can be identified from the correlation result using the phase shift of the consecutive training se- quences. Based on the CFOs estimation result, the CIRs can then he estimated according to the minimum mean square error (MMSE) criterion. The theoretic analysis and simulation results show that the proposed algorithm can effectively decouple the signal from different user nodes and the bit error rate (BER) per- formance curves are close to the ideal estimation when the user number is not large. 展开更多
关键词 wireless multimedia sensor networks (WMSN) orthogonal frequency division multiple access (OFDMA) multiple carrier frequency offsets (CFOs) multiple channel impulse responses (CIRs) minimum mean square error (MMSE)
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LTE系统中的Mean-OTDOA定位算法 被引量:7
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作者 陈亚军 彭建华 +1 位作者 黄开枝 罗文宇 《计算机应用研究》 CSCD 北大核心 2014年第6期1783-1786,共4页
由于LTE蜂窝网中远近效应的影响,终端测量到的邻近基站信号的定位参数会存在较大的偏差,导致OTDOA定位方法(到达时间差定位法)估计的终端位置存在较大误差。基于此,提出一种改进的Mean-OTDOA定位算法。首先估计终端与各基站的时延,然后... 由于LTE蜂窝网中远近效应的影响,终端测量到的邻近基站信号的定位参数会存在较大的偏差,导致OTDOA定位方法(到达时间差定位法)估计的终端位置存在较大误差。基于此,提出一种改进的Mean-OTDOA定位算法。首先估计终端与各基站的时延,然后对终端与多基站的距离测量值进行平均,作为OTDOA定位方法中的参考距离,最后利用泰勒级数展开法对终端位置进行估计。仿真结果表明,该算法可提高终端的定位精度,在基站数目为5、测量误差标准差为50 m时,本算法的均方根误差比OTDOA算法降低了5.2039 m,且随着基站数目的增加,定位精度的改善程度优于OTDOA算法。 展开更多
关键词 LTE系统 远近效应 mean-OTDOA定位算法 泰勒级数 均方根误差
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最小化误差平方和k-means初始聚类中心优化方法 被引量:42
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作者 周本金 陶以政 +1 位作者 纪斌 谢永辉 《计算机工程与应用》 CSCD 北大核心 2018年第15期48-52,共5页
传统的k-均值算法对初始聚类中心和孤立点敏感,文中以最大程度地减少误差平方和为基本思想,提出一种最大化减少当前误差平方和的k-means初始聚类中心优化方法。在初始聚类中心选择阶段,每次增加聚类中心时,计算所有数据点作为当前聚类... 传统的k-均值算法对初始聚类中心和孤立点敏感,文中以最大程度地减少误差平方和为基本思想,提出一种最大化减少当前误差平方和的k-means初始聚类中心优化方法。在初始聚类中心选择阶段,每次增加聚类中心时,计算所有数据点作为当前聚类中心能够减少的误差平方和,选择能够最大化减少误差平方和的数据点作为聚类初始中心。利用真实数据集,同其他算法进行对比,实验结果表明该方法在选择初始聚类中心方面能够有效地减少聚类的迭代次数,提高聚类质量。同时人工模拟数据表明该方法对孤立点相对不敏感。 展开更多
关键词 聚类 K-均值算法 误差平方和 孤立点
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一种局部概率引导的优化K-means++算法 被引量:7
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作者 王海燕 崔文超 +1 位作者 许佩迪 李闯 《吉林大学学报(理学版)》 CAS 北大核心 2019年第6期1431-1436,共6页
针对K-means++算法选取初始聚类中心计算误差平方和时,实验次数对误差平方影响不准确的问题,提出一种PK-means++算法.结果表明,该算法在进行分散数据聚类时,在同一K值情形下,聚类后的误差平方和较原K-means++算法更稳定,从而更好地保证... 针对K-means++算法选取初始聚类中心计算误差平方和时,实验次数对误差平方影响不准确的问题,提出一种PK-means++算法.结果表明,该算法在进行分散数据聚类时,在同一K值情形下,聚类后的误差平方和较原K-means++算法更稳定,从而更好地保证了随机实验取值的稳定性. 展开更多
关键词 聚类分析 K-means++算法 概率 误差平方和
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基于密度优化初始聚类中心的K-means算法 被引量:7
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作者 王艳娥 安健 +1 位作者 梁艳 康晶晶 《计算机技术与发展》 2020年第12期99-105,共7页
针对K-means算法随机选择初始聚类中心,对噪音和异常点比较敏感,聚类结果过多依赖于专家经验从而缺乏一定客观性的问题,提出一种新的度量样本密度的方法优化K-means算法对初始聚类中心的选择。该方法基于样本实际分布,以最优超球体中样... 针对K-means算法随机选择初始聚类中心,对噪音和异常点比较敏感,聚类结果过多依赖于专家经验从而缺乏一定客观性的问题,提出一种新的度量样本密度的方法优化K-means算法对初始聚类中心的选择。该方法基于样本实际分布,以最优超球体中样本个数与超球体中样本相似性作为度量样本密度的关键,能够有效选出较优的聚类中心,使得选择的初始聚类中心更接近样本集的实际分布。算法在乳腺癌数据集、常用UCI数据集以及人工模拟数据集上进行测试,实验结果表明,与已有同类方法相比,该算法在各数据集上的聚类评价指标均有提高,而且运行速度更快,聚类结果更稳定,聚类准确率更高:在乳腺癌数据集wdbc上的准确率为91.04%,提高了6%。在Iris数据集上的准确率为94%,提高了5%。 展开更多
关键词 K-meanS算法 密度 去噪 最优超球体 均方差 噪声数据
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Selection of the Linear Regression Model According to the Parameter Estimation 被引量:35
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作者 Sun Dao-de Department of Computer, Fuyang Teachers College, Anhui 236032,China 《Wuhan University Journal of Natural Sciences》 EI CAS 2000年第4期400-405,共6页
In this paper, based on the theory of parameter estimation, we give a selection method and, in a sense of a good character of the parameter estimation, we think that it is very reasonable. Moreover, we offer a calcula... In this paper, based on the theory of parameter estimation, we give a selection method and, in a sense of a good character of the parameter estimation, we think that it is very reasonable. Moreover, we offer a calculation method of selection statistic and an applied example. 展开更多
关键词 parameter estimation linear regression model selection criterion mean square error
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Adaptive compensating method for Doppler frequency shift using LMS and phase estimation 被引量:7
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作者 Jing Qingfeng Guo Qing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第5期913-919,共7页
The novel compensating method directly demodulates the signals without the carrier recovery processes, in which the carrier with original modulation frequency is used as the local coherent carrier. In this way, the ph... The novel compensating method directly demodulates the signals without the carrier recovery processes, in which the carrier with original modulation frequency is used as the local coherent carrier. In this way, the phase offsets due to frequency shift are linear. Based on this premise, the compensation processes are: firstly, the phase offsets between the baseband neighbor-symbols after clock recovery is unbiasedly estimated among the reference symbols; then, the receiving signals symbols are adjusted by the phase estimation value; finally, the phase offsets after adjusting are compensated by the least mean squares (LMS) algorithm. In order to express the compensation processes and ability clearly, the quadrature phase shift keying (QPSK) modulation signals are regarded as examples for Matlab simulation. BER simulations are carried out using the Monte-Carlo method. The learning curves are obtained to study the algorithm's convergence ability. The constellation figures are also simulated to observe the compensation results directly. 展开更多
关键词 Doppler frequency shift least mean square minimum phase shift keying unbiased estimation Matlab simulation.
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THE SUPERIORITY OF EMPIRICAL BAYES ESTIMATION OF PARAMETERS IN PARTITIONED NORMAL LINEAR MODEL 被引量:4
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作者 张伟平 韦来生 《Acta Mathematica Scientia》 SCIE CSCD 2008年第4期955-962,共8页
In this article,the empirical Bayes(EB)estimators are constructed for the estimable functions of the parameters in partitioned normal linear model.The superiorities of the EB estimators over ordinary least-squares... In this article,the empirical Bayes(EB)estimators are constructed for the estimable functions of the parameters in partitioned normal linear model.The superiorities of the EB estimators over ordinary least-squares(LS)estimator are investigated under mean square error matrix(MSEM)criterion. 展开更多
关键词 Partitioned linear model empirical Bayes estimator least-squares estimator mean square error matrix
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Novel K-best detection algorithms for MIMO system
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作者 向星宇 仲文 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期1-5,共5页
Aiming at the optimum path excluding characteristics and the full constellation searching characteristics of the K-best detection algorithm, an improved-performance K-best detection algorithm and several reduced-compl... Aiming at the optimum path excluding characteristics and the full constellation searching characteristics of the K-best detection algorithm, an improved-performance K-best detection algorithm and several reduced-complexity K-best detection algorithms are proposed. The improved-performance K-best detection algorithm deploys minimum mean square error (MMSE) filtering of a channel matrix before QR decomposition. This algorithm can decrease the probability of excluding the optimum path and achieve better performance. The reducedcomplexity K-best detection algorithms utilize a sphere decoding method to reduce searching constellation points. Simulation results show that the improved performance K-best detection algorithm obtains a 1 dB performance gain compared to the K- best detection algorithm based on sorted QR decomposition (SQRD). Performance loss occurs when K = 4 in reduced complexity K-best detection algorithms. When K = 8, the reduced complexity K-best detection algorithms require less computational effort compared with traditional K-best detection algorithms and achieve the same performance. 展开更多
关键词 sorted QR decomposition K-best sphere decoding maximum-likelihood detection minimum mean square error
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High Order Stable Infinite Impulse Response Filter Design Using Cuckoo Search Algorithm 被引量:2
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作者 N.Agrawal A.Kumar +1 位作者 V.Bajaj G.K.Singh 《International Journal of Automation and computing》 EI CSCD 2017年第5期589-602,共14页
In this paper, an efficient technique for optimal design of digital infinite impulse response (IIR) filter with minimum passband error (ep), minimum stopband error (es), high stopband attenuation (As), and als... In this paper, an efficient technique for optimal design of digital infinite impulse response (IIR) filter with minimum passband error (ep), minimum stopband error (es), high stopband attenuation (As), and also free from limit cycle effect is proposed using cuckoo search (CS) algorithm. In the proposed method, error function, which is multi-model and non-differentiable in the heuristic surface, is constructed as the mean squared difference between the designed and desired response in frequency domain, and is optimized using CS algorithm. Computational efficiency of the proposed technique for exploration in search space is examined, and during exploration, stability of filter is maintained by considering lattice representation of the denominator polynomials, which requires less computational complexity as well as it improves the exploration ability in search space for designing higher filter taps. A comparative study of the proposed method with other algorithms is made, and the obtained results show that 90% reduction in errors is achieved using the proposed method. However, computational complexity in term of CPU time is increased as compared to other existing algorithms. 展开更多
关键词 Cuckoo search algorithm infinite impulse response (IIR) means square error (MSE) evolutionary algorithm stability.
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Raman spectroscopy de-noising based on EEMD combined with VS-LMS algorithm 被引量:3
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作者 俞潇 许亮 +1 位作者 莫家庆 吕小毅 《Optoelectronics Letters》 EI 2016年第1期16-19,共4页
This paper proposes a novel de-noising algorithm based on ensemble empirical mode decomposition(EEMD) and the variable step size least mean square(VS-LMS) adaptive filter.The noise of the high frequency part of spectr... This paper proposes a novel de-noising algorithm based on ensemble empirical mode decomposition(EEMD) and the variable step size least mean square(VS-LMS) adaptive filter.The noise of the high frequency part of spectrum will be removed through EEMD,and then the VS-LMS algorithm is utilized for overall de-noising.The EEMD combined with VS-LMS algorithm can not only preserve the detail and envelope of the effective signal,but also improve the system stability.When the method is used on pure R6G,the signal-to-noise ratio(SNR) of Raman spectrum is lower than 10dB.The de-noising superiority of the proposed method in Raman spectrum can be verified by three evaluation standards of SNR,root mean square error(RMSE) and the correlation coefficient ρ. 展开更多
关键词 algorithmS mean square error Raman scattering System stability
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Using self-location to calibrate the errors of observer positions for source localization 被引量:2
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作者 Wanchun Li Wanyi Zhang Liping Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第2期194-202,共9页
The uncertainty of observers' positions can lead to significantly degrading in source localization accuracy. This pa-per proposes a method of using self-location for calibrating the positions of observer stations in ... The uncertainty of observers' positions can lead to significantly degrading in source localization accuracy. This pa-per proposes a method of using self-location for calibrating the positions of observer stations in source localization to reduce the errors of the observer positions and improve the accuracy of the source localization. The relative distance measurements of the two coordinative observers are used for the linear minimum mean square error (LMMSE) estimator. The results of computer si-mulations prove the feasibility and effectiveness of the proposed method. With the general estimation errors of observers' positions, the MSE of the source localization with self-location calibration, which is significantly lower than that without self-location calibra-tion, is approximating to the Cramer-Rao lower bound (CRLB). 展开更多
关键词 self-location errors of the observer positions linearminimum mean square error (LMMSE) estimator accuracy of thesource localization Cramer-Rao lower bound (CRLB).
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A New Multi-sensor Data Fusion Algorithm Based on EMD-MMSE 被引量:2
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作者 张琦 阙沛文 +1 位作者 陈天璐 黄晶 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第2期153-158,共6页
A new multi-sensor data fusion algorithm based on EMD-MMSE was proposed.Empirical mode decomposition(EMD)is used to extract the noise of every time series for estimating the variance of the noise.Then minimum mean squ... A new multi-sensor data fusion algorithm based on EMD-MMSE was proposed.Empirical mode decomposition(EMD)is used to extract the noise of every time series for estimating the variance of the noise.Then minimum mean square error(MMSE)estimator is used to calculate the weights of the corresponding series.Finally,the fused signal is the weighted addition of all these series.The experiments in lab testified the efficiency of this method.In addition,the comparison in fusion time and fusion results with existing fusion method based on wavelet and average technique shows the advantage of this method greatly. 展开更多
关键词 data fusion empirical mode decomposition (EMD) minimum mean square error (MMSE) multisensor system
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