Sky is the limit: flying access networks for beyond 5G

The use of flying robots (drones) carrying radio transceiver equipment is the new promising frontier in our quest towards ever more flexible, adaptable and spectrally efficient wireless networks. Beyond obvious challenges within regulatory, control, navigation, and operational domains, the deployment of autonomous flying radio access network (Fly-RANs) also come with a number of exciting new research problems such as the issue of optimal automatic placement of the drones in non-trivial propagation scenarios (i.e. scenarios where the optimal placement is not just dictated by a trivial geometry argument due to shadowing effects, e.g. in cities).  We present several different approaches, lying at the cross-roads between machine learning, signal processing and optimization. One approach involves the reconstruction of a city map from sampled radio measurements which can have application beyond the realm of communications.