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arXiv · 2402.18847

Flexible Precoding for Multi-User Movable Antenna Communications

Songjie Yang·Wanting Lyu·Boyu Ning·Zhongpei Zhang·Chau Yuen
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Abstract

This letter rethinks traditional precoding in multi-user wireless communications with movable antennas (MAs). Utilizing MAs for optimal antenna positioning, we introduce a sparse optimization (SO)-based approach focusing on regularized zero-forcing (RZF). This framework targets the optimization of antenna positions and the precoding matrix to minimize inter-user interference and transmit power. We propose an off-grid regularized least squares-based orthogonal matching pursuit (RLS-OMP) method for this purpose. Moreover, we provide deeper insights into antenna position optimization using RLS-OMP, viewed from a subspace projection angle. Overall, our proposed flexible precoding scheme demonstrates a sum rate that exceeds more than twice that of fixed antenna positions.

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Songjie Yang, Wanting Lyu, Boyu Ning, Zhongpei Zhang, Chau Yuen. 2024-02-29. Flexible Precoding for Multi-User Movable Antenna Communications. https://doi.org/10.1109/lwc.2024.3372569

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