Cognition in UAV-Aided 5G and Beyond Communications: A Survey

In recent years, unmanned aerial vehicles (UAVs) have attained significant interest in different applications including aerial surveillance, providing wireless coverage, precision agriculture, power lines & oil rigs monitoring and construction, etc. The UAVs implicit peculiarities, e.g., swift mobility, increase in payload capabilities and airborne time, place it as a potential candidate for many applications in next-generation wireless communications. In this article, a comprehensive study on UAVs challenges, potential applications, and regulations is presented. In particular, fundamental challenges such as UAVs standardization, channel modeling, interference mitigation, collision avoidance and optimal trajectory design using deep reinforcement learning (RL) algorithms, energy harvesting techniques, security, and regulations are explored in light of most recent research development. Moreover, we propose a set of UAVs regulations to ensure its steady social integration and new business opportunities. Finally, various problems and future research directions regarding UAVs are presented.