Design and Performance Enhancements in Communication-Based Train Control Systems With Coordinated Multipoint Transmission and Reception
A communication-based train control (CBTC) system is an automated train control system that uses bidirectional train-ground communications to ensure the safe operation of rail vehicles. CBTC systems have stringent requirements for communication availability and latency. Due to unreliable wireless communications and frequent handoffs, existing CBTC systems can severely affect train control performance, train operation efficiency, and the utility of railways. In this paper, we use recent advances in coordinated multipoint transmission and reception (CoMP) to enhance the train control performance of CBTC systems. With CoMP, a train can communicate with a cluster of base stations (BSs) simultaneously, which is different from the current CBTC systems, where a train can only communicate with a single BS at any given time. In addition, unlike the existing works on CoMP, in this paper, the linear quadratic cost for the train control performance in CBTC systems is considered the performance measure. We jointly consider the BS cluster selection and handoff decision issues in CBTC systems. Moreover, in order to mitigate the impacts of communication latency on train control performance, we propose an optimal guidance trajectory calculation scheme in the train control procedure that takes full consideration of the tracking error caused by handoff latency. Simulation results show that train control performance can be substantially improved in our proposed CBTC system with CoMP.