LTE Application In High-Speed Train Communication System

With the rapid development of communication technology,4G communication networkswhich replace3G are becoming mainstream. Its development has also brought challenges tothe railway communication, especially for high-speed railway. Although the existing railwaycommunications network can meet the daily needs of voice services, but in the pursuit oftechnology that high data rate and the digitalization of multimedia integrated services today, itstill no way out. MIMO (Multiple-Input Multiple-Output) as LTE (Long Term Evolution) isthe key technology which with a solid foundation of "digital","wireless mobile technology,""broadband Integrated Services "can greatly improve the channel capacity of acommunication system for railway. MIMO technology can not only ensure reliabletransmission of information in train communication, but also can meet the demand of eachuser with multimedia services on the train. However, GSM-R, which is the primarycommunication system, can only satisfy the basic voice and business requirements withLow-speed transmission while it unable to meet the needs of future railway communicationsystem. Therefore, the study of MIMO technology is particularly important.MIMO is a technology that use multiple antenna in transmitter and receiver which canimprove the performance of system, through rational use of space channel resources, theMIMO can improve the data transmission rate and communication quality exponentiallywith Reasonable application of space channel resources, which also without the need forIncrease signal bandwidth and transmission power, Therefore, How could MIMO systemapplied to high speed rail communication systems will be the inevitable trend of the futurerailway communication system.In order to have a better improvement of the channel capacity of railway communicationsystem, a high-speed distributed MIMO systems is Proposed in this paper which fromCombined with distribution characteristics of high-speed rail line and its own advantages ofthe trains and the traditional MIMO systems, Through simulation analysis, one we know thatthe system can not only improve the communication channel capacity of the system,but alsohas better performance against shadow fading,on the other hand, how to install antennas onterrestrial antenna unit and train which based on the full account of cases of hardware cost toincrease system performance has also done a detailed overview.However, in the present situation, the communication system on the high-speed rail isstill used in GSM-R system. Although the system is capable of providing better reliability ofthe communication trains, but the reliability of communication is reduced due to the influenceof the Doppler effect in high-speed railway environment, Therefore, in order to improve thereliability of GSM-R system in the application of high-speed rail and with the optimization of the handoff combined with high-speed trains and its own characteristics, The handoffalgorithm is proposed based on the geographic location information in the paper whichCombined with previous research as well as its own characteristics of high-speed rail,Through the method of modeling, analysis, and simulations demonstrate that the method havebeen greatly improved in terms of reliability compared with the traditional one.