中文摘要：

铁路区间内列车间的通信通过轨道电路和基站间接实现，较多的通信环节易影响系统的可靠性，引发铁路交通安全问题。为此，针对铁路新避撞系统，提出基于超短波的列车间直接通信方案。通过理论分析证明方案的可行性，并给出超短波工作频段、列车间最大通信距离及收／发信机结构。分析列车间直接通信的通信链路，给出车站及区间列车运行场景中通信链路路径损耗的预算模型，同时结合接收功率的相关数值计算及仿真，验证该方案的可实现性。根据列车运行环境的特点，对通信链路中的衰落进行讨论，结果表明，多径传播和多普勒效应会造成信号严重衰落。

英文摘要：

The trains in the railway section communicate with each other by track circuit or base station indirectly, which has too many nodes and low reliability, also brings safety risk. In order to realize direct communication of train-to-train and the need of railway collision avoidance system, the train-to-train direct communication scheme is proposed, the ultrashort wave band, the maximum communication distance between trains and the structure of transceiver are selected for railway application requirements, also the feasibility of this technology is described. The link of the direct train-to-train communication is analyzed, the budget model of path loss of station and section are given, the calculated results under different conditions of the receiver power also with simulation are illustrated. Analysis result shows that the proposed technology can be realized. The fading in communication link is discussed with the character of train running environment, the result shows that the multipath propagation and Doppler effect lead to serious signal fading.