Physical layer security for UAV communications: A comprehensive survey

• Published in: China communications Vol. 19; no. 9; pp. 77 - 115
• Main Authors: Wang, Jue, Wang, Xuanxuan, Gao, Ruifeng, Lei, Chengleyang, Feng, Wei, Ge, Ning, Jin, Shi, Quek, Tony Q. S.
• Format: Journal Article
• Language: English
• Published: China Institute of Communications 01.09.2022; Nantong Research Institute for Advanced Communication Technologies,Nantong 226109,China%Department of Electronic Engineering,Tsinghua University,Beijing 100084,China%National Mobile Communications Research Laboratory,Southeast University,Nanjing 210096,China%Information Systems Technology and Design Pillar,Singapore University of Technology and Design,Singapore 487372,Singapore; School of Information Science and Technology,Nantong University,Nantong 226109,China; Nantong Research Institute for Advanced Communication Technologies,Nantong 226109,China%Department of Electronic Engineering,Tsinghua University,Beijing 100084,China; China Academy of Electronics and Information Technology,Beijing 100041,China%School of Transportation and Civil Engineering,Nantong University,Nantong 226109,China
• Subjects: air-to-ground channel; Autonomous aerial vehicles; Measurement; Physical layer security; Receivers; static/mobile UAV deployment; Trajectory optimization; Trajectory planning; Transmitters; UAV communications; air-to-ground channel; UAV communi-cations; static/mobile UAV deployment; trajectory optimization; physical layer security
• ISSN: 1673-5447
• DOI: 10.23919/JCC.2022.09.007

Due to its high mobility and flexible deployment, unmanned aerial vehicle (UAV) is drawing unprecedented interest in both military and civil applications to enable agile and ubiquitous connectivity. Mainly operating in an open environment, UAV communications benefit from dominant line-of-sight links; however, this on the other hand renders the communications more vulnerable to malicious attacks. Recently, physical layer security (PLS) has been introduced to UAV systems as an important complement to the conventional cryptography-based approaches. In this paper, a comprehensive survey on the current achievements of UAV-PLS is conducted. We first introduce the basic concepts including typical static/mobile UAV deployment scenarios, the unique air-to-ground channel and aerial nodes distribution models, as well as various roles that a UAV may act when PLS is concerned. Then, we start by reviewing the secrecy performance analysis and enhancing techniques for statically deployed UAV systems, and extend the discussion to the more general scenario where the UAVs' mobility is further exploited. For both cases, respectively, we summarize the commonly adopted methodologies, then describe important works in the literature in detail. Finally, potential research directions and challenges are discussed to provide an outlook for future works in the area of UAV-PLS.