A User Mobility Analysis Assistive MRO algorithm for handover parameters optimization in LTE SON system

In mobile network, handover (HO) prediction and decision is necessary, important and complex part, and HO parameters are set right or not, which will directly impact user's experience and system performance. In 2G/3G systems, manual setting of HO parameters is a time consuming task and low robust way. So in 3GPP LTE TR 36.902 R9 [1], Mobility Robustness Optimization (MRO) is defined to resolve the issue through self-configuring and self-optimizing method. In this paper, a new MRO algorithm named UMAA-MRO (User Mobility Analysis Assistive MRO) is proposed, in which a user mobility database and corresponding function module are setup to analyze user mobility and environment including route, time period, frequency, speed, weather, habit, etc, and help eNodeBs to select adaptive Time to Trigger (TTT), Hysteresis (Hys), Cell Individual Offset (CIO), Cell Reselection Parameters (CRs) for the User Equipment (UE) in user-level to reduce the number of HO-related Radio Link Failures (RLF), and avoid unnecessary or missed handovers. The handover results of the UE will be recorded in the database as the data for analyzing and selecting next time HO parameters in the same conditions. In the first part of the paper, some LTE MRO and HO background technologies and study points of the paper are introduced; the new algorithm is illustrated in the second part and the examples and algorithm evaluation will be provided to described its advantages in the third part; and a conclusion will be drawn finally.