Private Network Design And Coverage Optimization For High-Speed Railway Based On Gsm Network

With the rapid development of China’s society and economy, the rail transport systems need to hold more and more passenger traffic, which promote the continuing escalation and optimization of the railway system. Rail trips are more and more intensive, and the speed of the railway locomotive is faster and faster, which demands higher requirements on national wireless network coverage. The important issue the operators have to solve is to ensure the users could communicate with each other when they are in the train with high-speed. The high-speed railways cover a wide range of wireless environments. They pass through the cities, plains, hills, mountains, tunnels, bridges and so on. Moreover, the tightness of the carriages of the new high-speed trains such as CRH, is better than the previous trains, which makes it more difficult for the wireless signals propagating into the train. The complexity of the wireless environment, the high speed of the locomotive and the tightness of the carriages become the main challenges of the high-speed railway wireless communications.This paper is based on the topics of the high-speed railway coverage. First, the concept of the high-speed railway private network is introduced. The high-speed railway private network is the private network the communications operators established in order to solve the high-speed coverage problem. Its network parameter configurations are self-contained. The main work of this paper develops based on the given high-speed railway private network concept. The parameter configurations, power configurations, site selections, design of the distance between two sits, the configurations of the antenna radiation direction, the selection of the antenna main lobe width of the high-speed railway private network are studied from the view of the planning and design of the high-speed railway private network. The paper analyzes the high-speed railway coverage wireless environment, and gives the above factors configurations guidelines.Furthermore, the paper analyzes the optimization after the high-speed railway construction and submitting maintenance. The network construction process and device selection during the construction of high-speed railway is analyzed. The off-network, the unbalance configurations, the unreasonable antenna angle set and the antenna height during the practical coverage are also analyzed. Taking example of the Beijing-Tianjin high-speed railway, the above optimization problems are classified and studied. The concluding suggestion and results are given finally.