A Zero-Forcing Approach for the RIS-Aided MIMO Broadcast Channel

Dominik Semmler; Michael Joham; Wolfgang Utschick

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arXiv · 2311.11769

A Zero-Forcing Approach for the RIS-Aided MIMO Broadcast Channel

Dominik Semmler·Michael Joham·Wolfgang Utschick

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Abstract

We present efficient algorithms for the sum-spectral efficiency (SE) maximization of the multi-user reconfigurable intelligent surface (RIS)-aided multiple-input multiple-output (MIMO) broadcast channel based on a zero-forcing approach. These methods conduct a user allocation for which the computation is independent of the number of elements at the RIS, that is usually large. Specifically, two algorithms are given that exploit the line-of-sight (LOS) structure between the base station (BS) and the RIS. Simulations show superior SE performance compared to other linear precoding algorithms but with lower complexity.

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Dominik Semmler, Michael Joham, Wolfgang Utschick. 2023-11-20. A Zero-Forcing Approach for the RIS-Aided MIMO Broadcast Channel. https://arxiv.org/abs/2311.11769

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