CubeSat-Based 5G Cloud Radio Access Networks: A Novel Paradigm for On-Demand Anytime/Anywhere Connectivity

5G networks are expected to become the main infrastructure for security verticals such as disaster relief, humanitarian aid, and governmental and defense communications. In the case of defense services, especially, there are complex areas where coverage and connectivity are not reliable or are completely absent. Thus, the deployment of drones as mobile base stations (BSs) also needs a system designed for reliable backhaul based on satellites. However, a baseband unit (BBU) [devoted to baseband signal processing at the radio access network (RAN)] on drones is not a flexible solution and may require great power supply and processing capabilities, which a drone can hardly host.