In this paper, a robust diffusion affineprojection M-estimate (DAPM) algorithm is proposed for distributed estimation in the adaptive diffusion network. To eliminate the adverse effects of impulsive noise in case of ...
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In this paper, a robust diffusion affineprojection M-estimate (DAPM) algorithm is proposed for distributed estimation in the adaptive diffusion network. To eliminate the adverse effects of impulsive noise in case of the impulsive interference environment on the filter weight updates, this algorithm uses a robust cost function based on M-estimate function and is derived by the steepest-descent method. Simulation results verify that the proposed DAPM algorithm is effective for system identification scenarios in the presence of impulsive noise.
This paper utilizes the family of Aline projectionalgorithms (APAs) for distributed estimation in the adaptive diffusion networks. The diffusion APA (DAPA), the diffusion selective partial update (SPU) APA (DSPU-APA)...
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This paper utilizes the family of Aline projectionalgorithms (APAs) for distributed estimation in the adaptive diffusion networks. The diffusion APA (DAPA), the diffusion selective partial update (SPU) APA (DSPU-APA), the diffusion selective regressor (SR) APA (DSR-APA), and the diffusion dynamic selection (DS) APA (DDS-APA) are introduced in a unified way. In DSPU-APA, the weight coefficients are partially updated at each node during the adaptation. Therefore, the DSPU-APA has lower computational complexity in comparison to the DAPA. In addition, the convergence speed of the DSPU-APA is close to the DAPA. In DSR-APA, a subset of input regressors is optimally selected at each node during the adaptation. The dynamic selection of input regressors is performed in the DDS-APA. These strategies improve the performance of the conventional DAPA in terms of the steady-state error and computational complexity features. Also, by combining these algorithms, the DSPU-SR-APA and the DSPU-DS-APA are established, which are computationally efficient. The mean-square performance of the proposed algorithms is analyzed in the nonstationary environment and the generic relations for the theoretical learning curve and the steady-state error are derived. The analysis is based on the spatial-temporal energy conservation relation. The validity of the theoretical results and the good performance of the introduced algorithms are demonstrated by several computer simulations in diffusion networks.
作者:
Ikeda, KKyoto Univ
Dept Syst Sci Grad Sch Informat Kyoto 6068501 Japan
The affineprojection (AP) and the block orthogonal projection (BOP) algorithms are known to have good convergence properties even when the input signal is correlated. However, their convergence rates are not elucidat...
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The affineprojection (AP) and the block orthogonal projection (BOP) algorithms are known to have good convergence properties even when the input signal is correlated. However, their convergence rates are not elucidated yet, since they are based on orthogonal projection. and are too complicated to be analyzed. In this paper, we first consider their geometrical view and derive their convergence rates for white signals. Moreover, we provide an approximation method to evaluate the convergence rate for cot-related signals and show the results which are confirmed by computer simulations. The results imply that the convergence rate of the BOP algorithm gets saturated as the block size increases. (C) 2002 Elsevier Science B.V. All rights reserved.
Class of algorithms referring to the affine projection algorithms (APA) applies updates to the weights in a direction that is orthogonal to the most recent input vectors. This speeds up the convergence of the algorith...
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Class of algorithms referring to the affine projection algorithms (APA) applies updates to the weights in a direction that is orthogonal to the most recent input vectors. This speeds up the convergence of the algorithm over that of the normalized least mean square (NLMS) algorithm, especially for highly colored input processes. In this paper a new statistical analysis model is used to analyze the APA class of algorithms with unity step size. Four assumptions are made, which are based on the direction vector for the APA class. Under these assumptions, deterministic recursive equations for the weight error and for the mean-square error are derived. We also analyze the steady-state behavior of the APA class. The new model is applicable to input processes that are autoregressive as well as autoregressive-moving average, and therefore is useful under more general conditions than previous models for prediction of the mean square error of the APA class. Simulation results are provided to corroborate the analytical results. (C) 2015 Elsevier Inc. All rights reserved.
affine projection algorithms are useful adaptive filters whose main purpose is to speed the convergence of LMS-type filters. Most analytical results on affine projection algorithms assume special regression models or ...
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affine projection algorithms are useful adaptive filters whose main purpose is to speed the convergence of LMS-type filters. Most analytical results on affine projection algorithms assume special regression models or Gaussian regression data. The available analysis also treat different affineprojection filters separately. This paper provides a unified treatment of the mean-square error, tracking, and transient performances of a family of affine projection algorithms. The treatment relies on energy conservation arguments and does not restrict the regressors to specific models or to a Gaussian distribution. Simulation results illustrate the analysis and the derived performance expressions.
This paper presents the problem of distributed estimation in an incremental network based on the family of affineprojection (AP) adaptive algorithms. The distributed selective partial update normalized least mean squ...
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This paper presents the problem of distributed estimation in an incremental network based on the family of affineprojection (AP) adaptive algorithms. The distributed selective partial update normalized least mean squares (dSPU-NLMS), the distributed SPU-AP algorithm (dSPU-APA), the distributed selective regressor APA (dSR-APA), the distributed dynamic selection of APA (dDS-APA), dSPU-SR-APA and dSPU-DS-APA are introduced in a unified way. These algorithms have low computational complexity feature and close convergence speed to ordinary distributed adaptive algorithms. In dSPU-NLMS and dSPU-APA, the weight coefficients are partially updated at each node during the adaptation. In dSR-APA, the optimum number of input regressors is selected during the weight coefficients update. The dynamic selection of input regressors is used in dDS-APA. dSPU-SR-APA and dSPU-DS-APA combine SPU with SR and DS approaches. In these algorithms, the weight coefficients are partially updated and the input regressors are optimally/dynamically selected at every iteration for each node. In addition, a unified approach for mean-square performance analysis of each individual node is presented. This approach can be used to establish a performance analysis of classical distributed adaptive algorithms as well. The theoretical expressions for stability bounds, transient, and steady-state performance analysis of various distributed APAs are introduced. The validity of the theoretical results and the good performance of dAPAs are demonstrated by several computer simulations. (C) 2013 Elsevier GmbH. All rights reserved.
This paper proposes and develops a statistical analysis of affineprojection Normalized Correlation algorithm (AP-NCA) which is a combination of the affine projection algorithm (APA) and Normalized Correlation Algorit...
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ISBN:
(纸本)9781509006298
This paper proposes and develops a statistical analysis of affineprojection Normalized Correlation algorithm (AP-NCA) which is a combination of the affine projection algorithm (APA) and Normalized Correlation algorithm (NCA) for use in complex-domain adaptive filters. For impulse noise, two types are considered: one is found in observation noise and another at filter input. Through experiments with simulations and theoretical calculations of filter convergence, we demonstrate that the proposed AP-NCA is effective in making adaptive filters converge faster when the filter inputs are correlated, and robust in impulsive noise environments. It is observed that the theoretical convergence curves generally exhibit good agreement with the simulation results which shows that the analysis is valid for practical use.
One of the most significant challenges in adaptive filters is the slow convergence speed of the adaptive algorithm when dealing with highly correlated input signals. The adaptive affine projection algorithm (APA) whic...
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One of the most significant challenges in adaptive filters is the slow convergence speed of the adaptive algorithm when dealing with highly correlated input signals. The adaptive affine projection algorithm (APA) which is a generalized version of the well-known normalized least mean square algorithm, improves convergence speed against correlated input signals, but with a high steady-state weight error and considerable computational complexity. In this paper, to enhance the convergence performance of APA and reduce its complexity, a selective projection order APA and its proportionate variant are proposed. In these algorithms, the projection order varies during convergence. Initially, a high projection order is employed in adaptation, gradually decreasing as the mean-square deviation (MSD) of the weight error decreases. This adaptive approach maintains a high initial convergence speed while reducingss the steady-state error. Moreover, the computational complexity decreases during convergence. Additionally, we propose a combination of proportionate and non-proportionate adaptive algorithms, leveraging the variation of MSD during convergence. Simulation results in identification of sparse/dispersive channels confirm the improved convergence performance of the proposed algorithms compared to competing adaptive algorithms.
This paper provides an analysis of transient and steady-state behavior of different filtered-x affine projection algorithms. algorithms suitable for single-channel and for multichannel active noise controllers are tre...
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This paper provides an analysis of transient and steady-state behavior of different filtered-x affine projection algorithms. algorithms suitable for single-channel and for multichannel active noise controllers are treated within a unified framework. Very mild assumptions are posed on the active noise control system model, which is only required to have a linear dependence of the output from the filter coefficients. Therefore, the analysis applies not only to the linear finite impulse response models but also to nonlinear Volterra filters, i.e., polynomial filters, and other nonlinear filter structures. The convergence analysis presented in this paper relies on energy conservation arguments and does not apply the independence theory, nor does it impose any restriction to the signal distributions. It is shown in the paper that filtered-x affine projection algorithms always provide a biased estimate of the minimum mean square solution. Nevertheless, in many cases, the bias is small and therefore these algorithms can be profitably applied to active noise control.
This letter presents a new mathematical expression for the excess mean-square error (EMSE) of the affineprojection (AP) algorithm. The proposed expression explicitly shows the proportional relationship between the EM...
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This letter presents a new mathematical expression for the excess mean-square error (EMSE) of the affineprojection (AP) algorithm. The proposed expression explicitly shows the proportional relationship between the EMSE and the condition number of the input signals.
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