Reliability Design Of Radio Based Cab-signaling System

In order to improve the efficiency of railway transportation, the communiation-based train control method is developed.The Radio based cab-signaling method using wireless channel between the vehicle and station transports large sum of two-way transmission information,scheduling the regional trains through the control center,greatly improve the efficiency of railway transportation and with high reliability and safty. Many countries in the world had made progress in this area, research in our country is late but we do make certain achievements though countinious work .This Paper focus on the wireless signal system locomotive principle and structure and the function of the parts of subsystems, and analysis of the functions of various parts of subsystems.Then introduced The concept of the Safety Integrity Level (SIL).First, paper designed all parts of the system's structure based on the the principle of the Radio Based Cab-Signaling system,including stationary control system ,on board system and Wireless Communication System. It also introduced a number of subsystems related to the basic functions. Stationary control system is designed as double 2-vote-2 structure,the on board system is DMHS system,it also do research in the Handing off process between the main unit and the stand-by unit.The reliability of the system design is based on the safety of the whole system ,and has also introduce markov process modeling method to analysis different control structure.The paper choose markov process modeling method is mainly because it calculates the probability on time function and system status,model transfers from one status to another in a certain probability means some parts of the system fail to work.The model equals to the system differential equation,so the repair in queue and the redundancy treatment is also considered.The markov process modeling method is fit for the stochastic process with discrete time or discrete state ,it is easy to make up modeling and simulating,and with high precision. Paper also do research in general method of markov process,use the mathematics software Matlab to simulate ,and got result in different stuctures index,the difference got by changing system parameters can be used to lead a way to improving the reliability and safety of the system.The paper finally do research in the control mathod of the RBCS system,include autonomous polling and train login/logout method,to get different safety measures of the system control. So the RBCS system is proofed to be of high reliability and safety ,and can greatly improve the railway efficiency ,make sure of the railway safety.