1. Department of Electrical, Electronic and Information Engineering (DEI), University of Bologna, Bologna, Italy
2. Department of Mathematical, Physical and Computer Sciences, University of Parma, Parma, Italy
3. CINECA, Casalecchio di Reno (Bologna), Italy
4. Department of Electrical, Electronic and Information Engineering (DEI), University of Bologna, Bologna, Italy Integrated Systems Laboratory, ETH Zurich, Zurich, Switzerland