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arXiv · 2103.09104

STAR: Simultaneous Transmission And Reflection for 360° Coverage by Intelligent Surfaces

Yuanwei Liu·Xidong Mu·Jiaqi Xu·Robert Schober·Yang Hao·H. Vincent Poor·Lajos Hanzo
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Abstract

A novel simultaneously transmitting and reflecting (STAR) system design relying on reconfigurable intelligent surfaces (RISs) is conceived. First, an existing prototype is reviewed and the potential benefits of STAR-RISs are discussed. Then, the key differences between conventional reflecting-only RISs and STAR-RISs are identified from the perspectives of hardware design, physics principles, and communication system design. Furthermore, the basic signal model of STAR-RISs is introduced, and three practical protocols are proposed for their operation, namely energy splitting, mode switching, and time switching. Based on the proposed protocols, a range of promising application scenarios are put forward for integrating STAR-RISs into next-generation wireless networks. By considering the downlink of a typical RIS-aided multiple-input single-output (MISO) system, numerical case studies are provided for revealing the superiority of STAR-RISs over other baselines, when employing the proposed protocols. Finally, several open research problems are discussed.

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Yuanwei Liu, Xidong Mu, Jiaqi Xu, Robert Schober, Yang Hao, H. Vincent Poor, Lajos Hanzo. 2021-03-17. STAR: Simultaneous Transmission And Reflection for 360° Coverage by Intelligent Surfaces. https://doi.org/10.1109/mwc.001.2100191

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