A survey of energy efficient methods for UAV communication

Unmanned aerial vehicles (UAVs) are characterized by high flexibility and low deployment costs. Therefore, UAVs, in recent years, have been widely used in all walks of life, such as logistics services, search and rescue, agriculture and mining. These applications are highly dependent on UAV communication technology. However, the UAVs currently in use are still powered by low-power batteries, which greatly limits the operational life of UAVs, resulting in varying degrees of communication interruptions and cost increases. Therefore, improving the energy efficiency (EE) of UAV communication has become a key problem that needs to be urgently solved. This article gives a comprehensive review of methods to improve the EE of UAVs through UAV trajectory planning and deployment, resource allocation and management, energy saving communication protocol design and UAV energy harvesting (EH) and transfer. Additionally, this paper engages with related research to put forward some promising research directions.