Energy efficient adaptive cellular network configuration with QoS guarantee

Cellular network energy optimization is driven by different factors, namely transmission power and activity of the base stations. Quality of Service (QoS) of users is determined by received power, interference and bandwidth allocation and cannot be neglected. In existing studies, such drivers are treated separately, i.e., bandwidth allocation is fixed while power consumption is a variable to be optimized. This paper proposes a novel optimization framework which is aimed at minimizing the power consumption in cellular networks while affording a minimum bit rate for each mobile terminal by jointly considering energy consumption and QoS drivers. Mixed Integer Quadratic Programming (MIQP) based optimization framework solves the problems of the determination of the user association, the bandwidth allocation, the identification of the active base stations and their transmission power, guaranteeing also a requested service rate for each user. The proposed solution is shown to allow power savings of up to 60%, very close to the optimum lower bound, when the traffic is below the 35% of the maximum load.