Automated Optimal Configuring of Femtocell Base Stations' Parameters in Enterprise Femtocell Network

In the future B3G/4G communication systems, it is of broad prospect to implement the femtocell in the enterprise offices or other public places. However, the femtocell operations under such environment are significantly different from the macrocell as well as the usual residential femtocell, and the configuration and optimization are more complex. Although there have been a few works studying the optimization of enterprise femtocell networks, much more issues need to be further investigated. In this paper, we proposed an approach for improving the enterprise femtocell network's performance by automated optimizing the femtocell base station's (FBS's) pilot power as well as antenna pattern, and the recently proposed multi-element antenna which is appropriate for femtocell is also introduced. The aim of the optimization is to maximize femtocell network's coverage while minimize interference between femtocells, and thus improve network's performance parameters such as call drop ratio, average throughput, etc. To reduce the complexity of this algorithm, the optimizing procedure is divided into two steps: first a pilot power optimization approach based on Newton's method is used to maximize the coverage while reduce overlap area of femtocells; then a simulated annealing (SA) algorithm based FBSs' antenna patterns joint selection scheme is considered to further optimize the network. The numerical results showed that the proposed approach can significantly improve the network performance.