OFDM在轨道电路中应用的仿真研究

基于轨道电路的列控车载信息传输是目前铁路信号系统信息传输的主要方式,其中具有代表性的法国的UM2000轨道电路已经应用在我国新建的第一条铁路客运专线秦沈线上。本文针对在轨道电路带宽有限的情况下,如何提高传输速率并实现可靠传输信息这一铁路信号研究课题进行了仿真分析。提出利用正交频分复用(OFDM)多载波调制方式代替单载波调制方式对信息进行处理。在不改变带宽、符号周期和载频的情况下,将OFDM与FM(UM2000系统中所采用的调试方式)进行了分析比较,并对所传信息以OFDM调制方式进行了仿真分析。仿真结果证明,在相同的条件下,采用OFDM调制解调方式,可以大幅度地提高频带的利用效率,从而增加了传输的信息量。

Emulation Research of OFDM Application in Track Circuits

The track circuit based train control information transmission is the main mode of transmission of the railway signalling system. The French UM2000 track circuits repre sentative of the above mode have been applied on the Qinshen special passenger railway line.This paper is aimed at a most significant research subject on railway signalling, representative of the above mode have been increase the transmission speed and realize reliable transmission under the condition of track cireuits of limited widths. Emulation analysis is made. The OFDM(Orthogonal Frequency Division Multiplexing) multi-carrier modulation is used to process messages instead of the traditional single carrier modulation.Compare OFDM to FM (modulation mode of UM2000) without changing the bandwidth,symbol period and carrier frequency,and make emulational analysis of the transmitted information by OFDM modulation.The emulational results prove,that the OFDM modulation and demodulation may help to provide large data rates and improve spectral utilization to a great extent.