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arXiv · 2002.03209

Affine Combination of Diffusion Strategies over Networks

Abstract

Diffusion adaptation is a powerful strategy for distributed estimation and learning over networks. Motivated by the concept of combining adaptive filters, this work proposes a combination framework that aggregates the operation of multiple diffusion strategies for enhanced performance. By assigning a combination coefficient to each node, and using an adaptation mechanism to minimize the network error, we obtain a combined diffusion strategy that benefits from the best characteristics of all component strategies simultaneously in terms of excess-mean-square error (EMSE). Analyses of the universality are provided to show the superior performance of affine combination scheme and to characterize its behavior in the mean and mean-square sense. Simulation results are presented to demonstrate the effectiveness of the proposed strategies, as well as the accuracy of theoretical findings.

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Danqi Jin, Jie Chen, Cedric Richard, Jingdong Chen, Ali H. Sayed. 2020-02-08. Affine Combination of Diffusion Strategies over Networks. https://arxiv.org/abs/2002.03209

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