A Comprehensive Survey of Low-Complexity High-Security Techniques for UAV Communications

Unmanned Aerial Vehicles (UAVs), commonly known as drones, are found to play an important role in the progress of 6G wireless communication technology, including military applications, precision agriculture, intelligent transportation, smart surveillance, and disaster management. UAV-based communication is especially vulnerable to a variety of security risks, including eavesdropping, jamming, spoofing, denial-of-service, and hijacking, because of the wireless channel’s intrinsic accessibility and dynamic nature. Strict limitations on energy, compute, latency, and mobility also apply to the UAVs, making the use of traditional sophisticated cryptography methods impractical. Lightweight cryptography, physical layer security, blockchain-based authentication, federated learning, intrusion detection systems, and reinforcement learning-based secure resource allocation are just a few of the low-complexity and high-security solutions for UAV communications that are thoroughly surveyed in this paper. A wide range of UAV designs, including single UAVs, swarm-based UAVs, cellular-connected UAVs, satellite-assisted UAVs, and ad hoc UAV networks, are thoroughly covered in the survey. To offer a cohesive evaluation viewpoint, the performance metrics—such as energy consumption, latency, throughput, dependability, secrecy rate, computational complexity, and packet delivery ratio—are also included. This study provides the reader with organized data on the design of UAV communication systems that are safe, scalable, and energy-efficient for usage in upcoming wireless networks.