Rail Way Electromagnetic Environment Test, Analysis And Countermeasures

China has proposed the high-speed railway construction as strategic priority to new industries, according to long-term road network planning, high-speed railway construction will maintain a large-scale investment in China. However, there is a severe hidden danger in railway's communication network, the hidden electromagnetic interference can seriously affect the communication service quality of the railway communication system (GSM-R), and even lead to interruption of railway communication. Therefore, the electromagnetic environment testing and evaluation for railway is necessary, it can help us identify possible interference sources and then put forward feasible solutions in accordance with the interference test data.This paper introduces the basic component modules of the Baoxi railway's GSM-R system, gives the way to choose the construction sites of the base station and introduces the use of specific frequency bands, and especially gives details on the external interference and inner interference of the GSM-R system. This paper describes the necessity of the electromagnetic environment test and gives the basic steps of the testing process, testing standards and how to choose the test equipment. Hata model is used in this paper to calculate the loss of electromagnetic wave propagation in flat geographical areas and gives the simulation results accordingly, this paper also introduces some other electromagnetic wave propagation effects, which highlights the multi-path, Doppler Frequency shift and Doppler spread effects, and gives the simulation results and analysis according to these three effects.Finally, considering the interference caused by other signals and the effect of the multi-path, Doppler frequency shift and Doppler spread, combined with the actual situation of Baoxi railway, this paper proposed a type of antenna array and the power inversion Filter adaptation algorithm to depress the interference, and gives a theoretical analysis of anti-noise performance of the algorithm, and ultimately proves that the antenna array and the filter algorithm can be very good interference suppression to ensure the accuracy of communication system transmission.Results of this study are valuable to improve the electromagnetic environment testing and evaluation methods, and are important to further improve the safety of high-quality transmission of GSM-R system.