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arXiv · 2107.01404

Impact of Channel Aging on Zero-Forcing Precoding in Cell-Free Massive MIMO Systems

Wei Jiang·Hans Dieter Schotten
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Abstract

In the context of cell-free massive multi-input multi-output (mMIMO), zero-forcing precoding (ZFP) requires the exchange of instantaneous channel state information and precoded data symbols via a fronthaul network. It causes considerable propagation and processing delays, which degrade performance. This letter analyzes the impact of channel aging on the performance of ZFP in cell-free mMIMO. The aging effects of not only user mobility but also phase noise are considered. Numerical results in terms of per-user spectral efficiency are illustrated.

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Wei Jiang, Hans Dieter Schotten. 2021-07-03. Impact of Channel Aging on Zero-Forcing Precoding in Cell-Free Massive MIMO Systems. https://doi.org/10.1109/lcomm.2021.3094266

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