基于交换式以太网的列车通信网络实时性研究

Research on Real-time Performance of Train Communication Network Based on the Switched Ethernet Technology

以太网技术具有通信速率高、成本低的优势,目前国内外轨道交通行业都在研究发展基于以太网的列车通信网络。本文以兼容传统以太网协议为前提,研究提高工业以太网实时性的方法。在对列车通信网络需求分析的基础上,提出一种基于交换式以太网的列车通信网络的解决方案,为满足列车重要数据的实时性要求,提出列车级交换机采用混合调度算法,以降低列车实时数据在交换机缓冲队列中的排队时延。运用网络演算理论分析列车实时数据的端到端时延上界,并通过网络仿真技术验证本方案应用于列车通信网络这一特定场合的可行性和有效性。

Given the advantages of the Ethernet technology in terms of high transmission rate and low cost ,Eth‐ernet‐based train communication netw ork is under development in domestic and international rail transit indus‐tries .This paper first analyzes the method to improve real‐time performance of industrial Ethernet under the premise of the compatible traditional Ethernet protocol .And then based on a comprehensive requirement analy‐sis of train communication network ,this paper proposes a solution of train communication network based on the switched Ethernet ,where a hybrid scheduling algorithm is adopted on the train switches to ensure real‐time performance of important train data and to reduce queuing delay of real‐time data in the buffer queue at the switches .Using network calculus theory to analyze the end‐to‐end delay limit of the real‐time data ,the feasibil‐ity and the effectiveness of the scheme applied to the specific situation of train communication network are veri‐fied through the network simulation technology .