Energy-efficient coordinated sleep of LTE cells

Estimates indicate that about 80% of the power consumption of cellular networks must be supplied by operators. It is thus becoming of paramount importance to improve the energy efficiency of cellular networks at the operator side for an economic and environmentally-sustainable traffic growth. The introduction of discontinuous transmission - or sleep mode - at the base stations can enable a reduction of power consumption. To further enhance the reduction, this paper proposes to coordinate the sleep scheduling among neighboring cells. The sleep schedule coordination allows the inter-cell interference reduction, during the sleep periods. This paper assesses the performance of different sleep schedules (uncoordinated, coordinated orthogonal and coordinated partially-orthogonal) applied to cellular networks based on Long Term Evolution (LTE) protocol. Simulation results show that only by coordinating the sleep schedules it is possible to significantly improve the throughput and the energy efficiency. In particular, the coordinated orthogonal sleep schedule is able to reduce the energy consumption by over 80%, achieving a gain of about 13%.