Frame Loss Probability of Data Communication Subsystem in Train Control System
Tao Tang · Zhongguo tiedao kexue · 2008
Based on stochastic Petri net model and the failure factors of wireless channel,such as stochastic channel degradation,handover,and wireless access equipment failure,etc.,the frame loss probability model of Data Communication Subsystem(DCS) in train control system with both non-redundancy and redundancy configuration is proposed.Fixed-point iteration equation is adopted to solve frame loss probability of redundancy and non-redundancy decomposed DCS model.The influence of different configuration and train velocity on the fame loss probability of DCS is analyzed.Analysis and calculation results show that the frame loss probability of the redundancy configuration DCS is far lower than that of the non-redundancy one.The main reason is that the redundancy configuration DCS does not fail due to single AP failure,which can efficiently eliminate the impact of handover on the frame loss probability of DCS on frame loss probability.