On the coverage preservation problem in green cellular networks

Energy-efficient base station (BS) operation is a key design goal in green cellular networks. The most effective way for energy conservation of BSs is to switch on/off BS adaptively. However, such operations may induce the problem of creating coverage holes in the network. In this paper, we attempt to minimize the total power consumption of the network by switching on and off BSs adaptively while maintaining the network coverage. Specifically, we derive the optimal cell size and determine the optimal number of active BSs for power consumption minimization with network coverage preservation. We also propose a near-optimal polynomial-time heuristic algorithm for energy-efficient BS activation with network coverage preservation. The simulation results show that our algorithm can approach the performance upper bound with only approximately 3dB performance loss in overall network power consumption for a cellular network with various deployment strategies.