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arXiv · 2311.02958

Optimization of RIS Placement for Satellite-to-Ground Coverage Enhancement

Xingchen Liu·Liuxun Xue·Shu Sun·Meixia Tao
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Abstract

In satellite-to-ground communication, ensuring reliable and efficient connectivity poses significant challenges. The reconfigurable intelligent surface (RIS) offers a promising solution due to its ability to manipulate wireless propagation environments and thus enhance communication performance. In this paper, we propose a method for optimizing the placement of RISs on building facets to improve satellite-to-ground communication coverage. We model satellite-to-ground communication with RIS assistance, considering the actual positions of buildings and ground users. The theoretical lower bound on the coverage enhancement in satellite-to-ground communication through large-scale RIS deployment is derived. Then a novel optimization framework for RIS placement is formulated, and a parallel genetic algorithm is employed to solve the problem. Simulation results demonstrate the superior performance of the proposed RIS deployment strategy in enhancing satellite communication coverage probability for non-line-of-sight users. The proposed framework can be applied to various architectural distributions, such as rural areas, towns, and cities, by adjusting parameter settings.

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Xingchen Liu, Liuxun Xue, Shu Sun, Meixia Tao. 2023-11-06. Optimization of RIS Placement for Satellite-to-Ground Coverage Enhancement. https://arxiv.org/abs/2311.02958

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