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arXiv · 2302.04189

Physical Layer Security in Near-Field Communications

Zheng Zhang·Yuanwei Liu·Zhaolin Wang·Xidong Mu·Jian Chen
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Abstract

A near-field secure transmission framework is proposed. Employing the hybrid beamforming architecture, a multi-antenna base station (BS) transmits confidential information to a multi-antenna legitimate user (U) against a multi-antenna eavesdropper (E) in the near field. A two-stage algorithm is proposed to maximize the near-field secrecy capacity. Based on the fully-digital beamformers obtained in the first stage, the optimal analog beamformers and baseband digital beamformers can be alternatingly derived in the closed-form expressions in the second stage. Numerical results demonstrate that in contrast to the far-field secure communication relying on the angular disparity, the near-field secure communication mainly relies on the distance disparity between U and E.

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Zheng Zhang, Yuanwei Liu, Zhaolin Wang, Xidong Mu, Jian Chen. 2023-02-08. Physical Layer Security in Near-Field Communications. https://arxiv.org/abs/2302.04189

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