Distributed Beamforming and BS Sleep under Small Cell Network

Green telecommunication is becoming an important part in designing the wireless communication systems. Small Cell Network (SCN) is considered as one of the most promising techniques in the future cellular networks. In order to reduce the high power consumption caused by dense deployment of small base stations (BSs), we first propose a new decentralized precoding algorithm which aims to maximize the energy efficiency of the SCN and the suboptimal solution can be obtained by two times of iterations. For further consideration, when the quantity of UEs is low in the network, it is a waste of energy to open a BS to serve only a few UEs or provide a low data rate to the UEs. So we introduce a BS closing strategy, which takes advantage of the property of SCN that different BSs cover more overlapping areas. Simulation results show that the proposed decentralized precoding algorithm outperforms the traditional precoding algorithms such as BD precoding, and the sleep strategy does not only take linear time complexity but also improve the energy efficiency of the SCN obviously.