Broad Beam Reflection for RIS-Assisted MIMO Systems with Planar Arrays
Abstract
While reconfigurable intelligent surface (RIS)-aided user-specific beamforming has been vastly investigated, the aspect of utilizing RISs for assisting cell-specific transmission has been largely unattended. Aiming to fill this gap, we study a downlink broadcasting scenario where a base station (BS) sends a cell-specific signal to all the users located in a wide angular area with the assistance of a dual-polarized RIS. We utilize the polarization degree of freedom offered by this type of RIS and design the phase configurations in the two polarizations in such a way that the RIS can radiate a broad beam, thereby uniformly covering all azimuth and elevation angles where the users might reside. Specifically, the per-polarization configuration matrices are designed in such a way that the total power-domain array factor becomes spatially flat over all observation angles implying that the RIS can preserve the broad radiation pattern of a single element while boosting its gain proportionally to its aperture size. We validate the mathematical analyses via numerical simulations.
Keywords
Cite
@article{arxiv.2312.00482,
title = {Broad Beam Reflection for RIS-Assisted MIMO Systems with Planar Arrays},
author = {Parisa Ramezani and Maksym A. Girnyk and Emil Björnson},
journal= {arXiv preprint arXiv:2312.00482},
year = {2023}
}
Comments
To appear in the Proceedings of Asilomar 2023