Research On TD-LTE Network Planning And Optimization Technology For Complex Mountain High-speed Railway

With the rapid development of China's economy,high-speed rail has become a priority for people to travel long distances.As an important customer activity scenario,high-speed railway has an important significance for China Mobile's brand promotion.Many places in the country have completed the TD-LTE coverage research and actual engineering construction of high-speed railways.However,there are certain gaps in the research scene.With the rapid construction of high-speed railway networks,complex scenes,especially the construction of high-speed railways in mountainous areas,have been putting on the construction schedule,how to realize the planning and optimization of high-speed rail TDLTE communication network in mountainous complex scenes,ensuring the coverage and capacity of high-speed rail TD-LTE communication network,and satisfying the increasingly diversified business needs of users,has become a subject that needs further research.Firstly,based on the theory,combined with the practical experience of national high-speed rail TD-LTE network construction,this paper analyzes the characteristics of high-speed rail TD-LTE network under complex mountain conditions,and systematically sorts out the series of difficulties(Doppler frequency shift,frequent handover,high penetration loss of carriage,etc.)in network planning and optimization.The planning and optimization strategies of the TD-LTE network in this scenario are formulated in a targeted manner.On the basis of theoretical research,this paper combines the actual characteristics(many tunnels and bridges)and actual needs(More trains,more passengers,strong business demand,and strict quality requirements for VOLTE business)of the first mountain highspeed rail-Xicheng high-speed rail(Shaanxi section)in China,based on theoretical calculation and simulation,completes the site planning,capacity planning,frequency planning and planning of the Xicheng high-speed rail TD-LTE network.Supporting facilities planning,output the planning principle of Xicheng high-speed rail TD-LTE high-speed rail private network.Based on the planning principle and the actual situation of the Xicheng high-speed railway,this paper completed the equipment selection of the high-speed rail private network,and divided the tunnel,the tunnel,the bridge,the station and other different scenarios,and gave different coverage solutions,and finally completed the high-speed rail TD-The LTE network design scheme outputs and performs simulation verification to confirm the feasibility of the planning scheme.After the opening of the TD-LTE network of Xicheng high-speed railway,this paper combines the previous experience of high-speed rail network optimization,and explores different scenarios from coverage optimization,dual-frequency network collaborative optimization,and mobility optimization(interoperability strategy,neighboring,switching and reselection,TAC/LAC).The optimization strategy,and through on-the-spot field verification and revision,finally formed an optimization plan for the mountain high-speed rail,and based on this,completed the optimization of the Xicheng high-speed rail network.From the actual test and verification results and customer feedback after the operation of the high-speed rail,the Xicheng high-speed rail network has achieved high-quality coverage,and this research has achieved the intended purpose.