Challenges in propagation and channels in the networks of the future

Telecommunications are evolving fast, with many trends being observed at the several layers of the system/network structure. “Networks of the Future” and “Future Internet” became trends that encompass many views and goals, namely within mobile and wireless communications, most of them related to network aspects, as well as services and applications. This paper reviews the trends mentioned above, and then maps them onto the challenges that can be identified in the area of propagation and radio channel. These challenges extend beyond the usual concept of mobile and wireless cellular and local area networks, including application driven areas, like sensor and in-and on-body networks, device-to-device and machine-to-machine communications, and ambient and context awareness. On the other hand, more “classical” challenges are also at stake, coming from, e.g.: increase in data rates, hence bandwidth, hence carrier frequency; energy efficiency; efficient MIMO/beamforming; channel estimation and awareness; inclusion of antennas.