CDMA在FTTR中应用的载噪比分析  

CNR Analysis of CDMA used in Fiber to the Railway

作　　者：赵庆安[1] 戴未央[1] 王惠生[1] 

机构地区：[1]铁道部科学研究院

出　　处：《中国铁道科学》2000年第2期93-99,共7页China Railway Science

摘　　要：讨论了基于光纤无线网络总线链接方式的无线信号接入。在光纤到铁路沿线(FTTR)方案中对终端站接收的无线信号进行扩频编码 ,进入光纤通道并到达中心站。文中针对上行通道的 CNR给出了计算方法。结果表明 ,由于 CDMA的扩频作用减少了光信号噪声 。This article discusses a radio signal access based on the fiber radio bus link.In the solution of FTTR,the received radio signals was multiplied by a pseudorandom noise (PN) at Terminal Stations(TSs) ,and encapsulated into the envelope of optical signal by IM of LD.A calcuation method of the upstream CNR was given.The result shows that it is possible to increase the TSs and channels as per requirements in FTTR solution,because the optical signal beat noise is reduced by spectrum spreading of CDMA.

关 键 词：FTTR 光纤总线 无线接入 CDMA 上行通道 载噪比 

分 类 号：U285.16[交通运输工程—交通信息工程及控制]