Positioning And Power Optimization For UAV-Assisted Networks In The Presence of Eavesdroppers: A Multi-Armed Bandit Approach

Abstract

Unmanned Aerial Vehicles (UAVs) are becoming increasingly attractive for the ambitious expectations for 5G and beyond networks due to their several benefits. Indeed, UAV-assisted communications introduce a new range of challenges and opportunities regarding the security of these networks. Thus, in this paper we explore the opportunities that UAVs can provide for physical layer security solutions. Particularly, we analize the secrecy performance of a ground wireless communication network assisted by two friendly UAV jammers in the presence of an eavesdropper. To tackle the secrecy performance of this system, we introduce a new area-based metric, the weighted secrecy coverage, that measures the improvement on the secrecy performance of a system over a certain physical area given by the introduction of friendly jamming. Herein, the optimal 3D positioning of the UAVs and the power allocation is addressed in order to maximize the WSC. For that purpose, we provide a Reinforcement Learning-based solution by modeling the positioning problem as a Multi-Armed Bandit problem over three positioning variables for the UAVs: angle, height and orbit radius. Our results show that there is a trade-off between expediency of the positioning of the UAVs to positions of better secrecy outcome and energy expenditure, and that the proposed algorithm efficiently converges into a stable state.

Secure Precoding and User Association for Multiuser Hybrid RF/VLC Systems

“…On the other hand, considering that security and privacy issues are becoming ever more important to provide the level of trustworthiness and resilience expected for 6G, exploring hybrid RF/VLC systems from the security perspective is sparking increasing interest in the research community [7]. In this sense, physical layer security (PLS), which takes advantage of the wireless medium to enhance the secrecy of wireless communications, can be explored to design solutions capable of improving confidentiality in diverse scenarios of 6G [8]- [10]. Nonetheless, most of PLS techniques presented in the literature are designed for RF systems.…”

Secure Precoding and User Association for Multiuser Hybrid RF/VLC Systems

“…On the other hand, considering that security and privacy issues are becoming more and more important to provide the level of trustworthiness and resilience expected for 6G, exploring hybrid RF/VLC systems from the security perspective becomes an attractive research area [6]. In this sense, physical layer security (PLS), which takes advantage of the wireless medium to enhance the secrecy of wireless communications, may be explored to design solutions capable of improving confidentiality in diverse scenarios of 6G [7]- [9]. Nonetheless, most of PLS techniques presented in the literature are designed for RF systems, thus certain adaptations should be considered before employing PLS in VLC systems due to illumination requirements, such as dimming control and peakpower constraint [10].…”