Design And Research On The Module Of Electromagnetic Environment And The Interference Temperature In HSR-REM

In the wireless electromagnetic environment of the high-speed railway, the fast varying channel is caused by the high-speed movement of the train. Therefore, the reliability of the transmission and the effectiveness of the frequency spectrum, power and energy consumption in the train-ground communication system face new challenges. In order to meet these challenges and overcome these problems, spectrum environment maps was introduced into high-speed railway mobile communication systems, which includes the topography of wireless devices, path transmission loss, channel characteristic, electromagnetic interference as well as communication quality along the railway and so on. These testing results can be used for the prediction of channel, interference and communication quality. Discussions on two modules in the high-speed railway spectrum environment map (HSR-SEM), the electromagnetic environment simulating and interference detection module are discussed in the thesis.The electromagnetic environment module’s mainly focuses on establishing and simulating the electric wave propagation channel module. In this thesis, the WINNER II channel model is applied to the high-speed communication systems because it can satisfy the high data rate, packet transmission and low latency requirements. The thesis firstly introduces the WINNER II model detailedly and then selects the scenario which is suitable for high-speed railway communication. Simulation results on parameter analysis, channel coefficients and characteristics of WINNER II channel are provided in the thesis.With the help of the interference temperature technology which senses the hole spectrum in cognitive radio, the improved interference temperature algorithm MTM-SVD is used to quantify the interference along the high-speed railway. Further, we use the interference threshold of the spectrum environment to detect interference. The simulation result shows that the proposed algorithm can detect the the interference effectively, therefore can improve the anti-jamming capability of high-speed railway communication system Through the estimate of the interference, we can further obtain the high-speed electromagnetic environment forecast information. According to the result of interference decision, we adjust the communication scheme to achieve the purpose of interference avoidance. Simultaneously, we can clearly know the realtime spectrum usage to raise the utilization of spectrum.