Research On Interference Detection Technology Of LTE Vehicle-to-Ground Wireless Communication System In Urban Rail Transit

In recent years,urban rail transit has developed rapidly,and communication-based Train Control(CBTC)also needs to keep continuously developing.LTE-M based on TD-LTE(Time Division-Long Term Evolution)wireless communication technology has become an industry trend in the new generation of rail transit communication systems to gradually replace WLAN.At present,LTE-M is adopted as the urban rail transit communication system in multiple lines of several cities.Under the requirements of high reliability and high transmission quality of services such as CBTC.How to ensure that services such as CBTC meet the requirements of rail transit services.Wireless interference is a crucial issue in urban rail transit communication systems.Due to mutual interference between interferences in various frequency bands is inevitable,and interference optimization is the key to improve network quality.The interference detection is complex.How to solve interference is a vital part of safety of rail transit operations.According to the electromagnetic propagation environment of LTE-M,this paper studies whether the LTE-M signal system meets the requirements of urban rail transit services.Currently,whether the LTE-M signal quality meets the service requirements is mostly based on experience and engineering principles,and there is a lack of targeted test method.This paper mainly studies the common types of wireless interference in the existing LTEM system network of rail transit,and introduces the principles of various types of interference.Using the QoS-quality parameters of the LTE-M system,interference detection data,basic equipment information,etc.,the parameters are obtained for data classification,and the traditional spectrum analyzer interference detection and other methods are used for comparative test analysis,and the acquired parameter data is utilized.The automatic recognition algorithm based on co-channel interference and the automatic identification algorithm of inter-frequency interference are extracted.The same-frequency interference and inter-frequency interference are further studied.The three-mode interference recognition technology,overlapping coverage recognition technology,intermodulation interference recognition technology and blocking interference recognition technology are deeply studied.The spur interference identification technology is designed,and the LTE-M downlink analysis software is designed to realize the automatic identification output of the LTE-M system network interference,and then judge the interference source of the test cell according to the basic equipment information.The field test is used to verify the model,which proves that the model classification is accurate and reliable,and can further improve the development.The research results in this paper can solve the LTE-M network wireless interference problem providing a solution,and provide a practical application reference for LTE-M network big data comprehensive analysis.