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arXiv · 2105.06023

Robust Beamforming for Enhancing Security in Multibeam Satellite Systems

Jian Zhang·Min Lin·Jian Ouyang·Wei-Ping Zhu·Tomaso de Cola
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Abstract

This paper proposes a robust beamforming (BF) scheme to enhance physical layer security (PLS) of the downlink of a multibeam satellite system in the presence of either uncoordinated or coordinated eavesdroppers (Eves). Specifically, with knowing only the approximate locations of the Eves, we aim at maximizing the worst-case achievable secrecy rate (ASR) of the legitimate user (LU), subject to the constraints of per-antenna transmit power and quality of service (QoS) requirement of the LU. Since the optimization problem is non-convex, we first adopt the discretization method to deal with the unknown regions of the Eves and then exploit the log-sum-exp function to approximate the objective function. Afterwards, a BF method joint alternating direction method of multipliers (ADMM) with Dinkelbach iteration is presented to solve this non-convex problem. Finally, simulation results verify that our robust BF algorithm can effectively improve the security of multibeam satellite systems.

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Jian Zhang, Min Lin, Jian Ouyang, Wei-Ping Zhu, Tomaso de Cola. 2021-05-13. Robust Beamforming for Enhancing Security in Multibeam Satellite Systems. https://arxiv.org/abs/2105.06023

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