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arXiv · 2308.06539

Phase Shift Design for RIS-Aided Cell-Free Massive MIMO with Improved Differential Evolution

Trinh Van Chien·Cuong V. Le·Huynh Thi Thanh Binh·Hien Quoc Ngo·Symeon Chatzinotas
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Abstract

This paper proposes a novel phase shift design for cell-free massive multiple-input and multiple-output (MIMO) systems assisted by reconfigurable intelligent surface (RIS), which only utilizes channel statistics to achieve the uplink sum ergodic throughput maximization under spatial channel correlations. Due to the non-convexity and the scale of the derived optimization problem, we develop an improved version of the differential evolution (DE) algorithm. The proposed scheme is capable of providing high-quality solutions within reasonable computing time. Numerical results demonstrate superior improvements of the proposed phase shift designs over the other benchmarks, particularly in scenarios where direct links are highly probable.

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Trinh Van Chien, Cuong V. Le, Huynh Thi Thanh Binh, Hien Quoc Ngo, Symeon Chatzinotas. 2023-08-12. Phase Shift Design for RIS-Aided Cell-Free Massive MIMO with Improved Differential Evolution. https://arxiv.org/abs/2308.06539

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