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arXiv · 2004.08881

Diffusion LMS with Communication Delays: Stability and Performance Analysis

Fei Hua·Roula Nassif·Cédric Richard·Haiyan Wang·Ali H. Sayed
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Abstract

We study the problem of distributed estimation over adaptive networks where communication delays exist between nodes. In particular, we investigate the diffusion Least-Mean- Square (LMS) strategy where delayed intermediate estimates (due to the communication channels) are employed during the combination step. One important question is: Do the delays affect the stability condition and performance? To answer this question, we conduct a detailed performance analysis in the mean and in the mean-square-error sense of the diffusion LMS with delayed estimates. Stability conditions, transient and steady-state mean-square-deviation (MSD) expressions are provided. One of the main findings is that diffusion LMS with delays can still converge under the same step-sizes condition of the diffusion LMS without delays. Finally, simulation results illustrate the theoretical findings.

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Fei Hua, Roula Nassif, Cédric Richard, Haiyan Wang, Ali H. Sayed. 2020-04-19. Diffusion LMS with Communication Delays: Stability and Performance Analysis. https://doi.org/10.1109/lsp.2020.2990086

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