Cooperative base station operation for green dense heterogeneous networks

Dense heterogeneous networks are deployed for future wireless communication to meet the explosively increasing traffic demand. However, the network densification leads to a great amount of energy consumption especially the operation energy consumption. In this paper, we consider cooperative Base station (BS) operation in downlink dense heterogeneous networks consisting of one macro BS and several small cell BSs (SBSs). Two sleep modes operating at different time scales are proposed to save energy based on the features of wireless traffic, i.e., traffic is rather stable in long term but fluctuates in short term. When work in deep sleep mode, physical infrastructure of SBSs like baseband and circuits are switched off. In opportunistic sleep mode, SBS optimally switch off some antennas and associated physical components and perform cooperative transmission for users. The proposed cooperative BS sleep strategy for dense heterogeneous networks takes both traffic features and cooperation transmission into account, and can achieve great energy saving while guarantee the quality of service (QoS) of users.