基于802.11协议的CBTC系统数据通信子系统的探讨

Discussion of Digital Communication Subsystem for CBTC Based on 802.11

数据通信系统DCS是CBTC系统的核心,CBTC系统大多采用成熟的基于IEEE 802.11协议标准的无线局域网技术作为数字通信传输系统。本文利用OPNET Modeler 14.5仿真平台,对CBTC系统的数据通信子系统建模,以802.11b标准为例进行仿真,在不同的无线数据传输速率及列车运行速度下,对无线局域网性能变化进行分析,提出具有冗余设备的列车以保证数据通信的可靠传输。随着人们对列车控制系统性能及多样化信息服务需求的增加,基于802.11协议的CBTC系统也存在一些需要解决的问题。

The Communication Based Train Control（CBTC）system is an advanced train control system. The DCS system plays an important role in information interaction between ground equipment and vehicle equipment in CBTC. The current CBTC system is mostly using the IEEE 802.11 standard of the wireless local area network technology as its digital transmission system. This paper used the OPNET Modeler 14.5 simulation platform and made the model of the data communications subsystem for the CBTC system. Using the 802.11b standard for a simulation example, under different wireless data transmission rates and different train traffic speeds, the wireless local area network performance changes were analyzed. This paper pointed out that trains with redundancy equipment attained effective data transmission. With the increasing demand of the train control system performance and demand of diversified service,some problems remain to be solved with the CBTC system based on 802.11.