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arXiv · 2005.01910

Reconfigurable Intelligent Surface (RIS)-Enhanced Two-Way OFDM Communications

Chandan Pradhan·Ang Li·Lingyang Song·Jun Li·Branka Vucetic·Yonghui Li
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Abstract

In this paper, we focus on the reconfigurable intelligent surface (RIS)-enhanced two-way device-to-device (D2D) multi-pair orthogonal-frequency-division-multiplexing (OFDM) communication systems. Specifically, we maximize the minimum bidirectional weighted sum-rate by jointly optimizing the sub-band allocation, the power allocation and the discrete phase shift (PS) design at the RIS. To tackle the main difficulty of the non-convex PS design at the RIS, we firstly formulate a semi-definite relaxation problem and further devise a low-complexity solution for the PS design by leveraging the projected sub-gradient method. We demonstrate the desirable performance gain for the proposed designs through numerical results.

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Chandan Pradhan, Ang Li, Lingyang Song, Jun Li, Branka Vucetic, Yonghui Li. 2020-05-05. Reconfigurable Intelligent Surface (RIS)-Enhanced Two-Way OFDM Communications. https://arxiv.org/abs/2005.01910

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