Corrado Puligheddu, Department of Electronics and Telecommunications, Politecnico di Torino, Torino, Italy Jonathan Ashdown, Air Force Research Laboratory, Wright-Patterson AFB, OH, USA Carla Fabiana Chiasserini, Department of Electronics and Telecommunications, Politecnico di Torino, Torino, Italy Francesco Restuccia, Institute for the Wireless Internet of Things, Northeastern University, Boston, MA, USA