高精度列车通信系统交换机优化设计

穆俊斌 冀云 孙景辉

摘 要： 现有高精度列车通信系统交换机由于未考虑交换机稳定运行时出现的环路现象，造成网络信息传输时的稳定性较差，因此对高精度列车通信系统交换机进行优化设计。优化设计后，交换机整体结构由主控制模块、以太网模块和POE供电模块三部分组成。在高精度列车内部构建环形网络，避免通信时某台交换机发生故障导致其余交换机不运行的状况发生；采用快速生成树协议算法降低环网恢复用时以及数据包丢失，促进列车内部网络信息传输的稳定运行；对交换机连接方式优化设计时用M12接头代替以太网接口和USB接口，使交换机的抗稳定能力和列车通信系统各设备间通信安全性增强，实现高精度列车通信系统中交换机的环网控制。实验结果表明，所设计交换机在高精度列车通信系统中应用效果较好，性能佳。

关键词： 高精度； 列车通信系统； 交换机； 优化设计； 环形网络； 快速生成树协议算法

中图分类号： TN915.05?34； U270 文献标识码： A 文章编号： 1004?373X（2018）16?0068?04

Abstract： The loop phenomenon occurred during the stable operation of the switcher is not considered in the current high?precision train communication system， resulting in poor stability of network information transmission. Therefore， an optimization design of the switcher is conducted for the high?precision train communication system. The overall structure of the switcher after its optimization design is composed of the main control module， Ethernet module， and POE power supply module. The loop network is constructed inside the high?precision train to avoid the situation that one switcher′s failure causes other switchers′ failure. The fast spanning tree protocol algorithm is adopted to reduce the loop network recovery time and data packet loss， so as to facilitate the stable operation of information transmission in the train internal network. During the optimization for the connection mode of switchers， the M12 connector is used to replace the Ethernet interface and USB interface， so as to enhance the stability of the switcher and the communication security between devices in the train communication system， and realize the loop control of the switcher in the high?precision train communication system. The experimental results show that the designed switcher has a good application effect and performance in the high?precision train communication system.

Keywords： high precision； train communication system； switcher； optimization design； loop network； fast spanning tree protocol algorithm

0 引 言

随着城市铁道建设的不断发展，高精度列车如地铁内的网络通信技术也在高速进步，实现高精度列车内的通信需要采用以太网技术，其具有数据传输快、应用范围广以及设备兼容性好的优势[1]，成为发展通信系统的重要应用，而交换机作为实现通信能力的关键设备，对其进行质量、性能和功能上的优化改进，有利于提升列車内通信能力[2]。过去高精度列车通信系统的交换机未考虑交换机稳定运行时出现的环路现象，造成网络信息传输时的稳定性较差。……