Fade Duration Based Sleep Mode Activation in Dense Femtocell Cluster Networks

Recently, much attention has been given to femtocell networks and their potential application in high peak load areas such as airports and arrival train stations. A dense femtocell network provides an efficient and low cost solution to respond to high traffic demand. When a densely deployed femtocell network is underutilized during low traffic load this creates interference among registered and unregistered users. In this paper, a cluster-based sleep mode activation optimization method based on fade duration is proposed along with an algorithm for hybrid femtocell networks. The femtocell sleep mode initiation is based on fade duration outage probability (FDOP). The proposed method also considers distances between femtocell access points and resources taken as benchmarks for optimization of sleep mode activation. FDOP determines the probability that a fade will occur of a duration beyond which a connection is considered in an outage state. Since the proposed method is based on FDOP rather than SNR, it provides a much better prediction of user application performance. The results based on this proposed method show an improvement in power efficiency, interference mitigation, and resource utilization.