Research On Self-optimized Techniques Of SON For Home ENode B In TD-LTE System

LTE is the latest standard for the next generation of mobile communication networks. InLTE system, the number and structure of network parameters have become large and complex.To reduce operational and capital expenditure by diminishing human involvement in networkoperational tasks, SON is introduced to LTE, which is considered as the one of the promisingarea to reduce network operation and maintenance costs, and to achieve dynamic optimizationof the system.The function of SON consists of self-configured, self-optimized and self-healed.Mobility Robustness Optimization and Mobility Load Balancing are two most important usecases of self-optimized. MRO aims to solve handover problems in the cell, and MLB aims tocope with the unequal loads between different cells. This paper researches these two use casesdeeply and proposes solutions in the femtocells, also finishs the system-level simulation andanalysis for the proposed solutions.Firstly, introduce LTE system architecture and state-of-the-art SON technology, analysethe main functions of SON self-optimized and its key technology related to mobility.Sencondly, some deeply researches have been done on MRO and MLB. For MRO, we analysethe workable solutions in multiple aspects such as detection of handover error, judgment ofhandover error, and optimization of parameters. For MLB, we analyse the load monitoringprograms, trigger mechanism of algprithms, target selection of handover, and the way tooptimize parameters. And especially present a preliminary coordination program to deal withthe possible conflicts between MLB and MRO algorithm. Finally an integrated andenforceable solutions for MRO and MLB are worked out.At last, a system-level simulation platform has been set up and the correspondingsimulation scenario has been designed to verify the performance of the algorithms. The resultsshow that proposed MRO solution can effectively detect handover errors and make areasonable parameter optimization, which results in the lower of radio link failure rate andhigher handover success rate. While the MLB solutions also can effectively alleviate thecongestion of the cell to achieve load balancing between each cell.