反向旁路——HFC网络快速实现双向传输的途径

Reverse Bypass——an Efficient Way of Implementing the Bidirectional Transmission

介绍兰州铁路局如何利用现有的单向有线电视网，采用反向旁路的方式，快速实现宽带互联网接入增值服务，有线电视网采用Cable Modem技术实现宽带接入，需要克服的困难是抑制反向汇聚噪声，光节点到末节点反向旁路传输方式可以极大地降低汇聚噪声产生的干扰。

This paper describes how the Lanzhou Railway Bureau Television Station to use the reverse bypass in the available unidirectional CATV Network to implement the value-added service in wide band internet access. When the CATV network is using cable modem technique to realize the wide band access, the major obstacle is to the return noises. The paper presents that taking a reverse bypass from optical line terminal （OLT） to end OLT could reduce the return noises significantly.