Availability Improvement for WLAN-Based Train-Ground Communication Systems in Communication-Based Train Control (CBTC)

Train-ground communication technology is one of the key technologies for communication-based train control (CBTC), which is an automated train control system for railways that ensures safe operation of rail vehicles using data communications. In CBTC systems, less service availability could cause train derailment, collision or even catastrophic loss of lives or assets. Therefore, the availability of train-ground communication should be carefully considered in designing CBTC systems. In this paper, we propose two WLAN-based train-ground communication schemes with redundancy to improve the availability in CBTC systems. The availability is analyzed using continuous time Markov chain (CTMC) model. Numerical examples illustrate that the proposed schemes with redundancy can significantly improve the availability of WLAN-based train-ground communication in CBTC systems.