Energy efficiency solutions for the mobile network evolution towards 5G: an operator perspective

This paper focuses on techniques or actions that the network operator should consider for the mobile network's evolution towards 5G from a sustainability point of view. To this end, the energy consumption of the Radio Access Network (RAN) is assessed when considering different load conditions (obtained by means of actual daily traffic profiles extracted from the live network) and different yearly traffic forecasts. An overview of different "what-if" scenarios towards 2020 and beyond is provided and energy consumption of the network is assessed by considering evolutionary Power Models (PMs) of future Base Stations (BSs) related to different Radio Access Technologies (RATs). Together with evolutionary PMs, many Energy Efficiency (EE) features that may be implemented within the network are also considered, with particular focus on EE features evaluated at higher time scale (from minutes to years), i.e., related to progressive network renewal with traffic steering options and legacy RATs' phase-off policies. These have been evaluated by using a software tool fed by actual traffic profiles, aiming at assessing EE performance at network level, by also considering the European Telecommunications Standards Institute (ETSI) EE specification ES 203 228, which is based on homogeneous clusters' evaluations that may be extrapolated at country level, providing useful information on the possible evolutions of the mobile networks in the view of future 5G systems.