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arXiv · 2403.03629

Spatially Selective Reconfigurable Intelligent Surfaces Through Element Permutation

Fredrik Rusek·Jose Flordelis·Kun Zhao·Erik Bengtsson·Olof Zander
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Abstract

A standard reconfigurable intelligent surface (RIS) can be configured to reflect signals from an arbitrary impinging direction to an arbitrary outgoing direction. However, if a signal impinges from any other direction, said signal is reflected, with full beamforming gain, to a specific direction, which is easily determined. The goal of this paper is to propose a RIS which \emph{only} reflects signals from the configured impinging direction. This can be accomplished by a RIS architecture that permutes the antenna elements in the sense that a signal is re-radiated from a different antenna than the one receiving the signal. We analytically prove this fact, and also discuss several variants and hardware implementations.

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Fredrik Rusek, Jose Flordelis, Kun Zhao, Erik Bengtsson, Olof Zander. 2024-03-06. Spatially Selective Reconfigurable Intelligent Surfaces Through Element Permutation. https://arxiv.org/abs/2403.03629

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