Study And Design For Communication System Of Digital Track Circuit

In this paper, the communication system of the digital track circuit is studied and designed. The digital communication system is based on the French UM-71 track circuit and these equipments in the French UM-71 tract circuit are remained. This design method is easy to utilize the general control equipment of railway, is extended easily and is applied easily. In addition, it can decrease development cost and shorten development time. Through comparing and analyzing the up-date technology, it is sure that the communication system is the controls signal transmission. Its operation mode as follows: in the communication system, the CPU is DSP(Digital Signal Processor) chip TMS320C6711B; it receives data from track sensors through ADC(Analog-Digital Converter), communicates with the superior computer though CAN(Controller Area Network) bus, synthesizes digital signal to use DDS(Direct Digital Frequency Synthesis) technique, modulates the digital signal to use MSK(Minimum Shift Keying) technique and sends the digital signal to the power amplification element; using CPLD(Complex Programmable Logic Device) designs the logic relation among chips; it is a fault-tolerant system using TMR(Three Modular Redundancy) technique. For simplifying the design, the system is grouped into central processing element, information collect element, signal sended element, communication element, auxiliary element and TMR structure. The circuit board of the system is made and debugged. The circuit board is checked with the design requirements of the system. Funtional blocks were debugged firstly, and the whole circuit was debugged secondly. The circuit boards are set in the processor indoor rack. Every processing element has one transmit port and three receive port.In our country, railway is used at wide range. With advancing requirements about velocity, density and comfortable degree of train, a traditional train-run-control system can not meet the requirement visibly. It is necessity that a new train-run-control system that can meet the requirement about new transportation mode of our country on rapid transit railway and that can compatibility with the general control equipment of railway. The design of the digital track circuit may meet development requirement and trend of our country track circuit. Therefore, the communication system of the digital track circuit has wide marketplace and development potential.