Design And Application Of TD-LTE Network Coverage Scheme For High Speed Railway

With the continuous development of communication technology and the rapid construction of communication networks,China's 4G network is gradually replacing the 3G network,and become the new mainstream communication technology.In addition,with the rapid construction of high-speed railway,China's high-speed railway operating mileage has exceeded 19,000 km,more and more people will first choose to take high-speed railway when they travel,making high-speed railway's communication quality is more important.Because of its high speed,large bandwidth,low delay and high spectrum utilization,LTE network has become the best technical means to cover high-speed railway.Because high-speed railway lines are usually very complex,the train is running very fast,business needs change at any time and other reasons,so high-speed trains on the communication signal coverage requirements is higher,that is,LTE wireless coverage requirements is higher.The research of this paper focuses on how to realize perfect 4G network coverage on high-speed railway,and provide users with high-speed and high-bandwidth communication services to realize mobile office at anytime and anywhere.In the future,"high-speed rail travel + high-speed Internet" will become the standard.High-speed railway has the following three main problems: 1.Train penetrating loss;2.Doppler frequency shift;3.High-speed frequent switching and re-selection.In this paper,the above three problems are studied in detail,as follows: For the train penetrating loss,we need to set the appropriate base station,the track distance,the antenna and the rail surface height,thus reducing the impact;for Doppler frequency shift,you can use low frequency band and select the frequency shift correction function with the wireless device;for high-speed frequent switching and re-selection,mainly through multiple RRU combined cell,reducing the number of switching to be resolved.This paper mainly studies the scheme of planning frequency band selection,equipment selection,site layout,link budget,switching overlapping band design,site spacing design,tunnel coverage design,capacity planning,public network and adjacent area planning and so on.At last,this paper sets a complete,scientific LTE high-speed railway network coverage planning program.Finally,the macro-station design and the tunnel scheme design of the TD-LTE network coverage of the Zhaoqing section of the Nanguang-Guangzhou high-speed railway are carried out by combining the actual conditions of the section of the Zhaoqing section of the Nanguang express railway.At the same time,the computer simulation of the design result shows the feasibility of the high-speed railway network coverage solution.The scheme discussed in this paper can ensure 4G network signal coverage at high speed and achieve a good user experience.