Application of Hilbert Huang Transform in Car Signal Demodulation

The car signal system is an important establishment to guarantee that a train operation safety. In recent years, with the rapid development of railway construction, the number of heavy haul trains and high-speed trains has increased rapidly. It makes the car signal system harder to demodulate the track circuit signal with higher interference and less response time. In order to ensure the safety of train operation, it is necessary to study a new demodulation algorithm for the car signal system. This paper takes widely used ZPW2000A track circuit as an example. We analyze the merits and demerits of its signal modulation mode, main interference sources and existing demodulation algorithms. After analyzing, we propose a new demodulation algorithm based on Hilbert Huang transform to solve these existing problems. Through the simulation results, the demodulation algorithm has outstand performances and a good application prospect in Car Signal system.