| With 3G and its long-term evolution (LTE) technology continuing to upgrade, transmission rate continues to accelerate, mobile communications get more and more widespread application. But the technology is more and more sensitive on the environment, under high-speed railway scenes, Doppler frequency shift caused by high-speed mobile, power loss caused by airtight carriage will make the advanced communications standard difficult to work properly. This paper analyzes and summarizes the difficulties in high-speed railway scene in 3G LTE communications and available technique to solve these difficulties. Private network building program is given; software simulation results demonstrate the communications environment under the program.However, only the result given above cannot demonstrate the solution is available for real, modern communication environment is very complex, different operators may have different standard, and different network may be coexistent under the same standard, so interference are inevitable. Estimation for the interference between high speed railway network and the traditional network are important, which could make suggestion to the operators for reducing throughput loss due to the coexistence and enhancing frequency efficiency. Analysis and simulation method for interference are discussed next, and simulation result are got by C++ program. Co-channel and adjacent channel interference with different parameters, for example ACIR and user-railway separate distance, are estimated. Conclusion is given at last.This paper is composed under the program of research on the interference of high-speed railway environment hold by China Mobile Company. |
