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arXiv · 2401.08237

Far- versus Near-Field RIS Modeling and Beam Design

Mohamadreza Delbari·George C. Alexandropoulos·Robert Schober·Vahid Jamali
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Abstract

In this chapter, we investigate the mathematical foundation of the modeling and design of reconfigurable intelligent surfaces (RIS) in both the far- and near-field regimes. More specifically, we first present RIS-assisted wireless channel models for the far- and near-field regimes, discussing relevant phenomena, such as line-of-sight (LOS) and non-LOS links, rich and poor scattering, channel correlation, and array manifold. Subsequently, we introduce two general approaches for the RIS reflective beam design, namely optimization-based and analytical, which offer different degrees of design flexibility and computational complexity. Furthermore, we provide a comprehensive set of simulation results for the performance evaluation of the studied RIS beam designs and the investigation of the impact of the system parameters.

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Mohamadreza Delbari, George C. Alexandropoulos, Robert Schober, Vahid Jamali. 2024-01-16. Far- versus Near-Field RIS Modeling and Beam Design. https://doi.org/10.1007/978-981-95-1814-2_8

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