Research On Algorithms For Maintaining Automatic Neighbor List In LTE System

3GPP LTE is the evolution of 3G standards,which can be used to improve the 3G air interface performance , due to the adoption of several advanced wireless communication technologies such as OFDM and MIMO. In the LTE system,automatic neighbor relation has become a requirement of the specification,so it is quite necessary to research on in LTE system . Next generation mobile networks will be of self-configuration,self-optimization and self-healing . Automatic neighbor relation function can realize the self-configuration and self-optimization of neighbor relation. It not only has the statistics of the whole network,but also can ease the working strength of the network planning and optimizing staff,In addition,it can reduce operating costs.Based on studying the 3GPP standards and analyzing the configuration of neighbor relation,the issue of automatic neighbor relation in LTE system is researched. Firstly,an automatic neighbor relation generating algorithm based on adaptive SINR threshold is proposed. SINR threshold and"vote model"is introduced in this algorithm. It generates a dynamic neighbor by introducing conditions of the real radio environment and investigating the cell types in LTE system. Simulation results show that different SINR threshold can affect the redundancy ratio and accuracy ratio of neighbor cell list.Secondly, an automatic neighbor relation pruning algorithm is proposed. It is reducing not only the redundancy ratio of neighbor cell list but also operation cost. Finally,the results of the simulation show that the handover success rate and dropping rate can be improved obviously by adopting the algorithm.