The Optimizing And Positioning Research Based On LTE Network Propagation Model

With the general and commercial use of LTE(Long Term Evolution)network in recent years,mobile communication network is now changing our daily life in unprecedented ways.Meanwhile,with the huge increasing amount of information demanded in modern society,human beings propose higher new expectations on LTE network.In the area of wireless communication,propagation model is the cornerstone for network plan and optimization.And in nowadays' urban area,as the accuracy of propagation model is directly affected by communication environment,thus,the complexity and variety of communication environment brings great uncertainty to the accurate prediction of propagation model,and also restricts the service quality of LTE network.Therefore,this paper has a research on the LTE network system,mainly aiming at studying the problems of complicated prediction accuracy of communication loss and poor positioning accuracy of positioning algorithm.The major achievements are as follows.First,starting from the research significance and research current conditions of propagation model optimization and positioning algorithm of LTE network,this paper states the optimization of LTE network propagation model through use of field test data and the feasibility of base station positioning through use of optimized propagation model,and then has explanations about the important and difficult points of propagation model optimization and positioning solution algorithm.Second,according to the prediction accuracy of propagation model and closely related characteristics of communication environment among the areas,this paper chooses a dense urban area in Wuhan as the data test site.The coverage condition of China Telecommunication LTE network in the chosen area,network engineering parameters,and the type of communication environment,through analysis of the above three aspects,this paper designs reasonable test plan and route.And then the COST-231Hata is chosen as communication prototype to be optimized.Third,to guarantee the accuracy of data,this paper processed some lost and unreasonable information data beforehand and thus well filtered those test data;and then this paper,by means of least square,uses the processed date to have Parameter Fitting,obtaining the propagation model parameter that suitable for the current communication environment.After verification,the prediction error mean of COST-231Hata reduces from 9.25 dBm to 1.16 dBm after optimization,and the standard deviation also reduces from 6.80 dBm to 3.03 dBm,which effectively increase the prediction accuracy.Finally,having positioning sites minimum error fitting by means of least square and characteristic equation,this paper,in the case of insufficient data in adjacent area,proposes hybrid positioning solutions by taking TA,direction angle,etc.as auxiliary parameters.The experimental results show that using non-optimized propagation model to have base station positioning,the distance mean value between locating and real site is 87.0544m.After optimization,the positioning distance error is 39.5978m.The positioning accuracy improves effectively.This paper gives a deep research on the LTE network system problems of complicated prediction accuracy of communication loss and poor positioning accuracy of positioning algorithm and obtains certain achievements on propagation model optimization and position.The achievements offers practical applicable value,and meanwhile provides references for LTE network plan,propagation model optimization,and positioning algorithm.