Millimeter-wave access and backhauling: the solution to the exponential data traffic increase in 5G mobile communications systems?

The exponential increase of mobile data traffic requires disrupting approaches for the realization of future 5G systems. In this article, we overview the technologies that will pave the way for a novel cellular architecture that integrates high-data-rate access and backhaul networks based on millimeter-wave frequencies (57-66, 71-76, and 81-86 GHz). We evaluate the feasibility of short- and medium-distance links at these frequencies and analyze the requirements from the transceiver architecture and technology, antennas, and modulation scheme points of view. Technical challenges are discussed, and design options highlighted; finally, a performance evaluation quantifies the benefits of millimeter- wave systems with respect to current cellular technologies.