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arXiv · 2307.12760

Dynamic Sub-array Based Modeling for Large-Scale RIS-assisted mmWave UAV Channels

Baiping Xiong·Zaichen Zhang·Jiangzhou Wang
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Abstract

Large-scale reconfigurable intelligent surface (RIS) can effectively enhance the performance of millimeter wave (mmWave) unmanned aerial vehicle (UAV) to ground communication link with obstructed line-of-sight (LoS) path by exploiting more reflecting units. However, the non-negligible array dimension of large-scale RIS and the mobile property of the terminals bring significant variations in propagation characteristics, making conventional channel models inapplicable. To address this issue, we propose a dynamic sub-array partition scheme to divide the large-scale RIS into sub-arrays by exploiting the Rayleigh distance criterion and the mobile property of the transceivers. Based on the proposed scheme, a novel non-stationary channel model for large-scale RIS auxiliary mmWave UAV-to-ground mobile networks is developed, which outperforms existing models with well balance between model complexity and accuracy. Numerical results are provided to verify our analysis.

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Baiping Xiong, Zaichen Zhang, Jiangzhou Wang. 2023-07-24. Dynamic Sub-array Based Modeling for Large-Scale RIS-assisted mmWave UAV Channels. https://arxiv.org/abs/2307.12760

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