A Distance-Sensitive Distributed Repulsive Sleeping Strategy for Densely-Deployed Small Cells in Green Cities

With the ultra-dense deployment of small cells, Base Station (BS) sleeping technology will play a critical role in future 5G green communications. However, conventional centralized BS sleeping strategies generate a large amount of communication overhead, which grows enormously with the number of BSs. Moreover, the coverage holes incurred by BS sleeping will also degrade the Quality of Service (QoS) performance of User Equipment (UE). To tackle this problem, we propose a Distance-Sensitive Distributed Repulsive Sleeping Strategy (DSDRSS) inspired by Hard Core Point Process (HCPP). DSDRSS realizes sleeping operations through the cooperation between SBSs in a Sleeping Cluster (SC), and does not rely on the feedback links between Small Base Stations (SBSs) and the control center. As a result, DSDRSS can not only enable flexible perception of traffic changes in sleeping area but also produce less communication overhead. Furthermore, we derive the coverage probability of UEs under the proposed scheme in terms of bandwidth resource and transmission rate constraints. Simulation results show that the proposed scheme can achieve equivalent coverage compared with the classic Random Sleep Strategy (RSS) and the General Repulsive Sleep Strategy (GRSS) with a much lower overhead cost.