一种列车数字无线信号中继系统的设计与验证  

Research and Design of a Train Digital Wireless Signal Repeater

作　　者：李涛[1] 陈特放[1] 

机构地区：[1]中南大学信息科学与工程学院,湖南长沙410075

出　　处：《铁道学报》2015年第4期46-50,共5页Journal of the China Railway Society

基　　金：国家自然科学基金(61273158)

摘　　要：为改善高速列车内部无线信号的覆盖质量,提出一种采用重采样滤波器的多级混合滤波器组来实现数字上、下变频的方法,该滤波器组可方便的实现整数倍和分数倍的抽取或内插。基于此方法设计一种列车数字无线信号中继系统,并对其进行算法级仿真和系统级实验。Matlab仿真结果表明,载波带宽为10 MHz,其阻带衰减值为80dB,带内波动为0.001dB时,数字上、下变频采用包含重采样滤波器的多级混合滤波器组,具有良好的通阻带逼近性,频谱无混叠现象。试验结果表明,基于该方法的中继系统的底噪声功率谱密度值为-136.9dBm/Hz,带内波动值为0.6768dB,指标优于技术规范要求。To improve the quality of wireless signal coverage inside the high speed trains ,a multilevel hybrid fil‐ters bank with resampling filter has been designed to realize digital up and down converion （DUC／DDC） meth‐od and to realize integral and fractional decimation or interpolation .Then a train wireless signal repeater based on DUC／DDC has been designed .Design and simulation of DUC／DDC of a 10 M Hz carrier bandwidth have been finished by Matlab .The simulation results show that the filters bank has a good approximation of the band pass/stop and the DUC／DDC spectrum does not show aliasing phenomenon ,when the stop band attenua‐tion value is 80dB and In‐band Ripple value is 0 .001dB .System testing results show that the background noise power spectral density value is -136.9 dBm/Hz ,and In‐band Ripple value is 0 .6768 dB .They are better than the common technical specifications .

关 键 词：数字上变频 数字下变频 重采样滤波器 列车 中继 

分 类 号：TN713[电子电信—电路与系统]