Application And Research Of Embedded Gateway Technology In Train Communication Network

Train Communication Network is a kind of computer local area network used in the train, which is used to gather and transmit the data from the on-board equipments in the train. It possessed many capabilities, such as control equipments, detection, and diagnosis, and has the ability to provide information for the passengers. The Train Communication Network consists two kinds of subnet one is Wire Train Bus (WTB) the other is Multiple Vehicle Bus (MVB). It very important to construction of Train Communication Network, which makes the train can control efficacious, run safety and passengers feel comfortable.Nowadays, the main technology used in Train Communication Network is WTB, MVB and LonWorks, the two technologies have been widely used in the train communication network. But the two kinds of FieldBus have their own drawback, such as the amount of data of the train is larger than the vehicle while the communication rate of the MVB is higher than the WTB, and because of the WTB and MVB is designed for the Train Communication Network, the cost is much higher; LonWorks is not strict to the transmission medium and the form of the topology, it can be both Train Bus and Vehicle Bus. But its biggest flaw is its relatively low transmission rate and difficult to meet the train communication network in the growing volume of data transmission.As these existing shortcomings in the Train Communication Network, in this paper I propose Industrial Ethernet Network used in the Train Communication Network, and do an in-depth study. The contents as follow:(1) Controller Area Network (CAN) is used in Wire Train Bus; Ethernet is used in Multiple Vehicle Bus and compared with other field bus. Consider as the current status of technology development, I propose a program that embedded Gateway used in the TCN, include with circuit diagram and program. In the whole design, I pay attention to the character of the locomotive equipments, especially in how to improve the ability of Anti-interference.(2) For the purpose of make the Industrial Ethernet Network used in Train Communication Network, after researching the TCP/IP carefully and deeply, I transplanted the Light weight Internal Protocols (LwIP) on ARM7 according to the actual needs, Basic protocols, such as IP, TCP, UDP, ICMP and ARP can run well.(3) Designed and realized CAN-Ethernet protocol conversion module, programmed the communication program, realized the CAN data and Ethernet data conversion. Developed Embedded Gateway PC test software by Visual Basical, and made lots of test, got lots of relative data. The test results indicate that research and design in this paper of the embedded gateway achieved well between CAN and Ethernet to communicate with each other.