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arXiv · 2404.08909

Capacity Maximization for RIS-assisted Multi-user MISO Communication Systems

M. S. S. Manasa·Kali Krishna Kota·Praful D. Mankar·Harpreet S. Dhillon
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Abstract

We consider a multi-user multiple input single output (MU-MISO) system assisted by a reconfigurable intelligent surface (RIS). For such a system, we aim to optimally select the RIS phase shifts and precoding vectors for maximizing the effective rank of the weighted channel covariance matrix which in turn improves the channel capacity. For a low-complex transmitter design, we employ maximum ratio transmission (MRT) and minimum-mean square error (MMSE) precoding schemes along with water-filling algorithm-based power allocation. Further, we show that MRT and MMSE exhibit equivalent performance and become optimal when the channel effective rank is maximized by optimally configuring the RIS consisting of a large number of elements.

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M. S. S. Manasa, Kali Krishna Kota, Praful D. Mankar, Harpreet S. Dhillon. 2024-04-13. Capacity Maximization for RIS-assisted Multi-user MISO Communication Systems. https://arxiv.org/abs/2404.08909

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