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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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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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Selection of the Linear Regression Model According to the Parameter Estimation 被引量:31
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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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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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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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Estimation of the Stress-Strength Reliability for Exponentiated Pareto Distribution Using Median and Ranked Set Sampling Methods 被引量:2
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作者 Amer Ibrahim Al-Omari Ibrahim M.Almanjahie +1 位作者 Amal S.Hassan Heba F.Nagy 《Computers, Materials & Continua》 SCIE EI 2020年第8期835-857,共23页
In reliability analysis,the stress-strength model is often used to describe the life of a component which has a random strength(X)and is subjected to a random stress(Y).In this paper,we considered the problem of estim... In reliability analysis,the stress-strength model is often used to describe the life of a component which has a random strength(X)and is subjected to a random stress(Y).In this paper,we considered the problem of estimating the reliability𝑅𝑅=P[Y<X]when the distributions of both stress and strength are independent and follow exponentiated Pareto distribution.The maximum likelihood estimator of the stress strength reliability is calculated under simple random sample,ranked set sampling and median ranked set sampling methods.Four different reliability estimators under median ranked set sampling are derived.Two estimators are obtained when both strength and stress have an odd or an even set size.The two other estimators are obtained when the strength has an odd size and the stress has an even set size and vice versa.The performances of the suggested estimators are compared with their competitors under simple random sample via a simulation study.The simulation study revealed that the stress strength reliability estimates based on ranked set sampling and median ranked set sampling are more efficient than their competitors via simple random sample.In general,the stress strength reliability estimates based on median ranked set sampling are smaller than the corresponding estimates under ranked set sampling and simple random sample methods.Keywords:Stress-Strength model,ranked set sampling,median ranked set sampling,maximum likelihood estimation,mean square error.corresponding estimates under ranked set sampling and simple random sample methods. 展开更多
关键词 Stress-Strength model ranked set sampling median ranked set sampling maximum likelihood estimation mean square error
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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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On the Estimation of a Univariate Gaussian Distribution: A Comparative Approach 被引量:1
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作者 Cliff R. Kikawa Michael Y. Shatalov +1 位作者 Petrus H. Kloppers Andrew C. Mkolesia 《Open Journal of Statistics》 2015年第5期445-454,共10页
Estimation of the unknown mean, μ and variance, σ2 of a univariate Gaussian distribution given a single study variable x is considered. We propose an approach that does not require initialization of the sufficient u... Estimation of the unknown mean, μ and variance, σ2 of a univariate Gaussian distribution given a single study variable x is considered. We propose an approach that does not require initialization of the sufficient unknown distribution parameters. The approach is motivated by linearizing the Gaussian distribution through differential techniques, and estimating, μ and σ2 as regression coefficients using the ordinary least squares method. Two simulated datasets on hereditary traits and morphometric analysis of housefly strains are used to evaluate the proposed method (PM), the maximum likelihood estimation (MLE), and the method of moments (MM). The methods are evaluated by re-estimating the required Gaussian parameters on both large and small samples. The root mean squared error (RMSE), mean error (ME), and the standard deviation (SD) are used to assess the accuracy of the PM and MLE;confidence intervals (CIs) are also constructed for the ME estimate. The PM compares well with both the MLE and MM approaches as they all produce estimates whose errors have good asymptotic properties, also small CIs are observed for the ME using the PM and MLE. The PM can be used symbiotically with the MLE to provide initial approximations at the expectation maximization step. 展开更多
关键词 mean squared ERROR Method of MOMENTS MAXIMUM LIKELIHOOD estimation Regression COEFFICIENTS
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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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ADJUSTMENT OF LEVELING NETWORK BY INFORMATION SPREAD ESTIMATION
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作者 WANG Xinzhou 《Geo-Spatial Information Science》 2001年第1期1-4,共4页
In practical parameter estimation,we have always chosen either Least Squares Estimation(LSE) or Robust Estimation.Since the distribution of observations is unknown,to select a correct estimation method is very difficu... In practical parameter estimation,we have always chosen either Least Squares Estimation(LSE) or Robust Estimation.Since the distribution of observations is unknown,to select a correct estimation method is very difficult.It is well known that if observations include gross errors,the result of LSE will be badly containinated.On the other hand,if observations do not include any gross errors,the result of robust estimation is not as good as that of LSE.To solve this problem,Wang (1999) developed an estimation method called Information Spread Estimation (ISE) based on the information spread principle.The ISE is a very good method for estimating one parameter which is very robust.However, most of instances in surveying data processing are multi_parameters’ estimation,owing to the inherent restrictions of ISE,it can not be applied to the surveying data processing directly.To apply the good method to the field of surveying data processing widely,the author has done the research deeply.This paper applies ISE successfully to the adjustment of leveling network by using the specialties of leveling. 展开更多
关键词 RESIDUAL error data SNOOPING robust estimation mean square of WEIGHT
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Generalized Class of Mean Estimators with Known Measures for Outliers Treatment
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作者 Ibrahim M.Almanjahie Amer Ibrahim Al-Omari +1 位作者 Emmanuel J.Ekpenyong Mir Subzar 《Computer Systems Science & Engineering》 SCIE EI 2021年第7期1-15,共15页
In estimation theory,the researchers have put their efforts to develop some estimators of population mean which may give more precise results when adopting ordinary least squares(OLS)method or robust regression techni... In estimation theory,the researchers have put their efforts to develop some estimators of population mean which may give more precise results when adopting ordinary least squares(OLS)method or robust regression techniques for estimating regression coefficients.But when the correlation is negative and the outliers are presented,the results can be distorted and the OLS-type estimators may give misleading estimates or highly biased estimates.Hence,this paper mainly focuses on such issues through the use of non-conventional measures of dispersion and a robust estimation method.Precisely,we have proposed generalized estimators by using the ancillary information of non-conventional measures of dispersion(Gini’s mean difference,Downton’s method and probabilityweighted moment)using ordinary least squares and then finally adopting the Huber M-estimation technique on the suggested estimators.The proposed estimators are investigated in the presence of outliers in both situations of negative and positive correlation between study and auxiliary variables.Theoretical comparisons and real data application are provided to show the strength of the proposed generalized estimators.It is found that the proposed generalized Huber-M-type estimators are more efficient than the suggested generalized estimators under the OLS estimation method considered in this study.The new proposed estimators will be useful in the future for data analysis and making decisions. 展开更多
关键词 Product estimators ratio estimators regression estimators ordinary least square Huber M mean squared error EFFICIENCY
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Estimation of Hazard Function for Censoring Random Variable by Using Wavelet Decomposition and Evaluation of MISE, AMSE with Simulation
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作者 Mahmoud Afshari Saeed Tahmasebi 《Journal of Data Analysis and Information Processing》 2014年第1期1-5,共5页
Wavelet analysis is one of the mostly new methods of pure and applied mathematics science. In this paper, we use the wavelet method to estimate the hazard function for censoring random variable. We consider the conver... Wavelet analysis is one of the mostly new methods of pure and applied mathematics science. In this paper, we use the wavelet method to estimate the hazard function for censoring random variable. We consider the convergence ratio of given estimator. Also we present the simulation in order to test purpose estimator by calculating the mean integrated squared error (MISE) and average mean squared error (AMSE). 展开更多
关键词 Wavelet ESTIMATOR CENSORING Random Variable mean square Integral ERROR Average mean square ERROR SIMULATION
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Estimation of Population Ratio in Post-Stratified Sampling Using Variable Transformation
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作者 Aloy Chijioke Onyeka Chinyeaka Hostensia Izunobi Iheanyi Sylvester Iwueze 《Open Journal of Statistics》 2015年第1期1-9,共9页
Extending the work carried out by [1], this paper proposes six combined-type estimators of population ratio of two variables in post-stratified sampling scheme, using variable transformation. Properties of the propose... Extending the work carried out by [1], this paper proposes six combined-type estimators of population ratio of two variables in post-stratified sampling scheme, using variable transformation. Properties of the proposed estimators were obtained up to first order approximations,(on–1), both for achieved sample configurations (conditional argument) and over repeated samples of fixed size n (unconditional argument). Efficiency conditions were obtained. Under these conditions the proposed combined-type estimators would perform better than the associated customary combined-type estimator. Furthermore, optimum estimators among the proposed combined-type estimators were obtained both under the conditional and unconditional arguments. An empirical work confirmed the theoretical results. 展开更多
关键词 Variable TRANSFORMATION Combined-Type ESTIMATOR Ratio Product and Regression-Type ESTIMATORS mean squared Error
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An Effective Method of SNR Estimation for LDPC-CPM
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作者 Rui Xue Bingbing Sun Tielin Zhu 《International Journal of Communications, Network and System Sciences》 2017年第5期146-153,共8页
The technique of SNR estimation is one of the key technologies in adaptive frequency hopping system. The methods of channel quality estimation for non-linear continuous phase modulation (CPM) signals have some limitat... The technique of SNR estimation is one of the key technologies in adaptive frequency hopping system. The methods of channel quality estimation for non-linear continuous phase modulation (CPM) signals have some limitations. Therefore, the algorithm of channel quality estimation for CPM signals is worthy of further study. Some similar phase characteristics between sampling CPM and MPSK motivate us to propose a channel estimation algorithm with applications to nonlinear CPM using linear modulation signal processing. A comprehensive analysis of LDPC-CPM schemes using proposed algorithm is presented, and simulation results indicate that the proposed method can not only estimate channel quality well but also make the normalized MSE (NMSE) of SNR estimate close to/less than 0.1 dB at SNR of 4 dB using short block codes. It shows that the algorithm in this paper is effective enough to estimate the signal to noise ratio (SNR). Meanwhile, the algorithm in this paper reduces the complexity of computation compared with other traditional algorithms. 展开更多
关键词 Frequency HOPPING Systems SIGNAL-TO-NOISE Ratio Nonlinear Continuous Phase Modulation Channel estimation mean square ERROR
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THE INEFFICIENCY OF THE LEAST SQUARES ESTIMATOR AND ITS BOUND
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作者 杨虎 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第11期1087-1093,共7页
It was suggested by Pantanen that the mean squared error may be used to measure the inefficiency of the least squares estimator. Styan[2] and Rao[3] et al. discussed this inefficiency and it's bound later. In this... It was suggested by Pantanen that the mean squared error may be used to measure the inefficiency of the least squares estimator. Styan[2] and Rao[3] et al. discussed this inefficiency and it's bound later. In this paper we propose a new inefficiency of the least squares estimator with the measure of generalized variance and obtain its bound. 展开更多
关键词 inefficiency relative efficiency mean squared error generalized variance matrix derivative best linear unbased estimator
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Estimation of Population Variance Using the Coefficient of Kurtosis and Median of an Auxiliary Variable under Simple Random Sampling
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作者 Tonui Kiplangat Milton Romanus Otieno Odhiambo George Otieno Orwa 《Open Journal of Statistics》 2017年第6期944-955,共12页
In this study we have proposed a modified ratio type estimator for population variance of the study variable y under simple random sampling without replacement making use of coefficient of kurtosis and median of an au... In this study we have proposed a modified ratio type estimator for population variance of the study variable y under simple random sampling without replacement making use of coefficient of kurtosis and median of an auxiliary variable x. The estimator’s properties have been derived up to first order of Taylor’s series expansion. The efficiency conditions derived theoretically under which the proposed estimator performs better than existing estimators. Empirical studies have been done using real populations to demonstrate the performance of the developed estimator in comparison with the existing estimators. The proposed estimator as illustrated by the empirical studies performs better than the existing estimators under some specified conditions i.e. it has the smallest Mean Squared Error and the highest Percentage Relative Efficiency. The developed estimator therefore is suitable to be applied to situations in which the variable of interest has a positive correlation with the auxiliary variable. 展开更多
关键词 Modified Ratio Type Variance Estimator Study VARIABLE AUXILIARY VARIABLE KURTOSIS MEDIAN Bias mean squared Error (MSE) PERCENTAGE Relative Efficiency (PRE) Simple Random Sampling
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Carrier frequency offset estimation for a generalized OFDMA uplink
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作者 Zhang Wei Wang Jing Chen Xiang 《High Technology Letters》 EI CAS 2011年第4期333-338,共6页
A residual carrier frequency offset (CFO) estimation scheme is proposed for the uplink of orthogonal frequency division multiple access (OFDMA) systems. Multiple access interference caused by CFOs in the uplink is... A residual carrier frequency offset (CFO) estimation scheme is proposed for the uplink of orthogonal frequency division multiple access (OFDMA) systems. Multiple access interference caused by CFOs in the uplink is investigated, as it severely affects the performance of a classical maximum likelihood (ML) frequency estimator. By the use of the estimated CFOs of the active users, the linear maximum mean square error (LMMSE) equalization is performed before the ML frequency estimator for the interference cancellation, which can help to sufficiently improve the estimation accuracy for the residual CFO of the incoming user. Analysis and simulations show that the modified ML estimator provides a tradeoff between estimation accuracy and computational complexity caused by the LMMSE interference cancellation, and the proposed method allows OFDMA systems flexibly allocating subcarriers to users. 展开更多
关键词 ofDMA upliak frequency synchronization maximum likelihood (ML) frequency estimator linear minhnum mean square error (LMMSE) equalization generalized carrier-allocation scheme (GCAS)
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A Modified Regression Estimator for Single Phase Sampling in the Presence of Observational Errors
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作者 Nujayma M. A. Salim Christopher O. Onyango 《Open Journal of Statistics》 2022年第2期175-187,共13页
In this paper, a regression method of estimation has been used to derive the mean estimate of the survey variable using simple random sampling without replacement in the presence of observational errors. Two covariate... In this paper, a regression method of estimation has been used to derive the mean estimate of the survey variable using simple random sampling without replacement in the presence of observational errors. Two covariates were used and a case where the observational errors were in both the survey variable and the covariates was considered. The inclusion of observational errors was due to the fact that data collected through surveys are often not free from errors that occur during observation. These errors can occur due to over-reporting, under-reporting, memory failure by the respondents or use of imprecise tools of data collection. The expression of mean squared error (MSE) based on the obtained estimator has been derived to the first degree of approximation. The results of a simulation study show that the derived modified regression mean estimator under observational errors is more efficient than the mean per unit estimator and some other existing estimators. The proposed estimator can therefore be used in estimating a finite population mean, while considering observational errors that may occur during a study. 展开更多
关键词 ESTIMATE Regression COVARIATES Single Phase Sampling Observational errors mean squared Error
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Performance of cumulant-based rank reduction estimator in presence of unexpected modeling errors
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作者 王鼎 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期992-1001,共10页
Compared with the rank reduction estimator(RARE) based on second-order statistics(called SOS-RARE), the RARE based on fourth-order cumulants(referred to as FOC-RARE) can handle more sources and restrain the negative i... Compared with the rank reduction estimator(RARE) based on second-order statistics(called SOS-RARE), the RARE based on fourth-order cumulants(referred to as FOC-RARE) can handle more sources and restrain the negative impacts of the Gaussian colored noise. However, the unexpected modeling errors appearing in practice are known to significantly degrade the performance of the RARE. Therefore, the direction-of-arrival(DOA) estimation performance of the FOC-RARE is quantitatively derived. The explicit expression for direction-finding(DF) error is derived via the first-order perturbation analysis, and then the theoretical formula for the mean square error(MSE) is given. Simulation results demonstrate the validation of the theoretical analysis and reveal that the FOC-RARE is more robust to the unexpected modeling errors than the SOS-RARE. 展开更多
关键词 fourth-order cumulants(FOC) rank reduction estimator(RARE) modeling error mean square error(MSE)
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