Radio Access Network energy minimization in multi-layer heterogeneous wireless systems

The energy consumption reduction in cellular systems is important from both economic and environmental perspectives. Nearly 80% of the energy in cellular systems is consumed by the Radio Access Network (RAN). In recent years, much research has been done to reduce the energy consumption in the RAN. However, existing models fail to capture the spatiotemporal variability of traffic demands, bit rate and power requirements, as well as the peculiarities in the energy consumption from different hardware components in a base station (BS). In this paper, a new RAN energy consumption model for multi-layer infrastructure-based heterogeneous wireless systems (IbHWS) is proposed. It captures all the aforementioned factors and accurately addresses the characteristics of IbHWS, where cellular systems are a particular case. A low-complexity algorithm is proposed to minimize the RAN´s energy consumption, and to satisfy all traffic demands in space and time. Based on extensive simulation results across a wide range of scenarios, the energy savings from this algorithm were on average 26%.