文章概述了有线电视网双向传输的几种接入技术，阐明了有线电视网双向传输光系统的特点，重点描述了光发射机、光放大器、光接收机和有线电视回传信道的应用。本文为某有线电视台双向网改造的实用实例，可为其他有线电视台的双向网改造提供参考。 This paper outlines several access technologies for bidirectional transmission over cable networks, clarifies the characteristics of bidirectional transmission optical systems over cable networks, and focuses on the application of optical transmitters, optical amplifiers, optical receivers and cable backhaul channels. This article is a practical example of the transformation of a two-way network of a cable television station, which can provide a reference for the transformation of bidirectional networks of other cable television stations.