Traffic-Aware Energy Optimizing Strategies for Multi-Cell Coordinated Green Cellular Networks

The ongoing 5G cellular networks are expected to meet the demands posed by the energy and radio resource crises, especially exploiting flexible management for the traffic in idle zone. In this paper, two energy optimizing solutions are proposed for macro-tier with the tradeoff consideration regarding spectrum efficiency and quality of service (QoS), which adapt to the instantaneous traffic variance based upon dynamic cell configuration. To characterize the optimal energy savings for base stations (BSs), an active cell rotation (ACR) scheme is cyclic activated to control the number of active BSs by appropriately scheduling different work patterns in the cell group, and hence, guarantee QoS requirement of the user equipment by a recovery mechanism. An improved cooperative ACR scheme is also proposed, which enables BSs to achieve better spectrum utilization while pursuing energy efficiency in terms of traffic load. In addition, closed-form stationary results as well as asymptotic analysis are also derived for formulating the traffic variance and state transitions by a Markov-based framework. The numerical performances indicate that the proposed methodologies can have positive effects on addressing greenness in both energy and spectrum domains while meeting the upcoming intense traffic and QoS requirements.