关键词: 毫米波, 工作频段, 隧道, 直接通信信道, 确定性模型, 统计模型

Abstract: It is most significant that train-to-train direct communication system can reduce the incidence of railway accidents effectively. However the direct communication system in plain environment has been proposed only. A new kind of multiband frequency receiver and transmitter that can be applied in both plain and tunnel environment are designed for direct communication system, then the communication performance in tunnel is analyzed. Firstly, the working frequency band and the communication distance of millimeter waves are decided for railway application requirements in tunnel. In the second place, the multiband frequency receiver and transmitter are proposed for both plain and tunnel environment, then the sensitivity of the designed receiver is computed. Moreover, the propagation mode of electromagnetic wave is analyzed in tunnel. Then the loss model of roughness and different form in tunnel is researched. The corresponding tent law and the multipath effect of propagating of electromagnetic wave are calculated. With all the above methods, the deterministic and statistic model of direct communication channel in single and double line railway tunnel are established. Meanwhile, the simulation results show the feasibility of the proposed 8 mm wave based direct communication scheme between trains.

Key words: millimeter waves, working frequency band, tunnel, direct communication channel, deterministic model, statistic model