Handover methods in carrier aggregation environment

Carrier aggregation is one of important technologies to improve the performance of LTE-A. When carrier aggregation is conducted, UE will have a set of serving cells (Component Carrier, CC), which introduces some new problems during handover decision process. By traditional handover method, channel condition of only one serving cell is considered, a proper set of serving cells can not be selected. In order to solve this problem, this paper proposes two handover methods considering the entire channel condition of multiple cells. Method 1 proposes to adjust handover margin according to difference between PCell and SCell in serving eNB; Method 2 proposes to make handover decision by equivalent channel condition of multiple cells in both serving eNB and neighboring eNB. Simulation results show that proposed methods provide higher cell edge throughput and a much smoother handover with almost same number of handovers.