Test and Analysis on the Interference to the CBTC Systems by Wi-Fi Signals

Abstract

Communication-Based Train Control (CBTC) system is an automated train control system using bidirectional train-ground communications to ensure the safe operation of rail vehicles. The interference from Wi-Fi signals to the CBTC signals has significant impacts on the train control performance. Most of previous works use data from simulation platform. This paper proposes a method to test the Wi-Fi interference to the Communication Based Train Control(CBTC) systems. The test is made mainly based on real subway, and supplemented by laboratory simulation platform. The collected data is to be compared and analyzed. The test result shows that the signal transmission mode of waveguide is the most reliable, followed by the leaky cable. The transmission mode of free wave has the worst anti-interference capability to Wi-Fi signals. This is because that both the waveguide and leaky cable transmission have a better encapsulation compared with the free space transmission. Also applying for specific bands can effectively reduce the interference transferred from Wi-Fi signals to the CBTC.