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arXiv · 2302.11127

Secure Antenna Selection and Beamforming in MIMO Systems

Zhenqiao Cheng·Nanxi Li·Ruizhe Long·Jianchi Zhu·Chongjun Ouyang·Peng Chen
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Abstract

This work proposes a novel joint design for multiuser multiple-input multiple-output wiretap channels. The base station exploits a switching network to connect a subset of its antennas to the available radio frequency chains. The switching network and transmit beamformers are jointly designed to maximize the weighted secrecy sum-rate for this setting. The principal design problem reduces to an NP-hard mixed-integer non-linear programming. We invoke the fractional programming technique and the penalty dual decomposition method to develop a tractable iterative algorithm that effectively approximates the optimal design. Our numerical investigations validate the effectiveness of the proposed algorithm and its superior performance compared with the benchmark.

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Zhenqiao Cheng, Nanxi Li, Ruizhe Long, Jianchi Zhu, Chongjun Ouyang, Peng Chen. 2023-02-22. Secure Antenna Selection and Beamforming in MIMO Systems. https://arxiv.org/abs/2302.11127

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