Mobility Analysis for Inter-Site Carrier Aggregation in LTE Heterogeneous Networks

In this paper we analyze the mobility performance for an LTE Heterogeneous Network with macro and pico cells deployed on different carriers. Cases with/without downlink inter-site carrier aggregation are investigated. Extensive system level simulations are exploited to quantify the performance. It is shown that not only does the use of inter-site carrier aggregation offer higher end-user throughput, but also several benefits in terms of improved mobility performance. Among others, it is shown that the performance becomes less sensitive to the setting of mobility parameters when inter-site carrier aggregation is used, while still keeping the handover signaling burden at an acceptable level. The probabilities of radio link failures, handover failures, and unnecessary handovers (also known as ping-pongs) are kept at a minimum for proposed the solution.