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arXiv · 2201.01739

Spectral Efficiency Optimization for mmWave Wideband MIMO RIS-assisted Communication

Pooja Nuti·Elyes Balti·Brian L. Evans
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Abstract

Reconfigurable Intelligent Surfaces (RIS) are passive or semi-passive heterogeneous metasurfaces and consist of many tunable elements. RIS is gaining momentum as a promising new technology to enable transforming the propagation environment into controllable parameters. In this paper, we investigate the co-design of per-subcarrier power allocation matrices and multielement RIS phase shifts in downlink wideband MIMO transmission using 28 GHz frequency bands. Our contributions in improving RIS-aided links include (1) enhanced system modeling with pathloss and blockage modeling, and uniform rectangular array (URA) design, (2) design of gradient ascent co-design algorithm, and (3) asymptotic (Big O) complexity analysis of proposed algorithm and runtime complexity evaluation.

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Pooja Nuti, Elyes Balti, Brian L. Evans. 2021-12-15. Spectral Efficiency Optimization for mmWave Wideband MIMO RIS-assisted Communication. https://arxiv.org/abs/2201.01739

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