Design and Analysis of a Threshold Offloading (TO) Algorithm for LTE Femtocell/Macrocell Networks

Abstract

LTE femtocells have been commonly deployed by network operators to increase network capacity and offload mobile data traffic from macrocells. A User Equipment (UE) camped on femtocells has the benefits of higher transmission rate and longer battery life due to its proximity to the base stations. However, various user mobility behaviors may incur frequent signaling overhead and degrade femtocell offloading capability. To efficiently offload mobile data traffic, we propose a Threshold Offloading (TO) algorithm considering the trade-off between network signaling overhead and femtocell offloading capability. In this paper, we develop an analytical model to quantify the trade-off and validate the analysis through extensive simulations. The results show that the TO algorithm can significantly reduce signaling overhead at minor cost of femtocell offloading capability. Moreover, this work offers network operators guidelines to set offloading threshold in accordance with their management policies in a systematical way.