Energy-Efficient Routing Protocols in Flying Ad Hoc Networks: A Comprehensive Review

Abstract

Flying Ad Hoc Networks (FANETs) have become an important research area because of their ability to provide communication between unmanned aerial vehicles (UAVs) in a wide range of applications such as military operations, agriculture, environmental monitoring, and smart transportation. However, the limited battery capacity of UAVs and the high dynamicity of FANETs make energy-efficient routing a great challenge. An efficient routing protocol should not only be energy efficient but also provide reliable communication, improve packet delivery, reduce delay, and increase network lifetime. Recently, many energy-efficient routing protocols have been proposed by researchers based on different approaches such as clustering, swarm intelligence, reinforcement learning, fuzzy logic, and hybrid techniques. Each approach has its own advantages and limitations depending on the network environment and application requirements. This paper offers an in-depth review of energy-efficient routing protocols that have been developed for FANETs. The reviewed protocols are analyzed according to their parameters used in the study, the simulator used, advantages, and limitations. We also provide comparisons that point out the strengths and weaknesses of existing approaches. In addition, this review highlights the main research challenges, such as high mobility, dynamic topology, routing overhead, scalability, and security, and discusses future research directions to design more intelligent and energy-aware routing protocols. The present review results and conclusions offer researchers a better understanding of current trends, and they also point out potential future research directions in energy-efficient FANET routing.