A delay tolerant control scheme for communication-based train control (CBTC) systems with unreliable wireless networks

Random transmission delays and packet drops are inevitable in communication-based train control (CBTC) systems, which could result in unnecessary traction, brake or even emergency brake of trains, losses of line capacity and passenger satisfaction. In this paper, we study the transmission delays in CBTC systems, analyze their impacts on the performances of CBTC systems, and propose a novel scheme to improve the performances of trains´ control system in CBTC by mitigating the impacts. Unlike the existing works that only consider a single train, we consider a group of trains in CBTC systems to improve the CBTC performances. Extensive simulation results are presented. We show that the current adopted control scheme experiences obvious performance losses under transmission delays. By contrast, our proposed scheme is tolerant of transmission delays, and can significantly improve the CBTC performances.