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同步数字体系SOH是建立在光纤传输基础上的一种技术体系,是在目前准同步数字体系PDH的基础上发展起来的一种新型数字通信体系,是从通信网的概念出发建立起来的全网时钟同步、统一光接口、大容量信息的传输、多种通信业务兼容、智能化管理、适应新技术发展要求的数字传输体系。同步数字系统的引入,使通信发展进入了一个新纪元,它适应现代信息社会多种新业务的要求,能够充分发挥光纤潜在的信息传输能力。一.SDH的特点与PDH相比,它有如下优点: 1.提供了世界统一的光接口, PDH没有世界统一的标准,只有地区性的信号速率和帧结构标准,即两大数字体系,
Synchronous Digital System SOH is a technology system based on optical fiber transmission. It is a new type of digital communication system developed on the basis of the present PDH (Synchronous Digital Hierarchy), which is based on the concept of communication network. Clock synchronization, unified optical interface, transmission of large-capacity information, compatibility of multiple communication services, intelligent management, and digital transmission system adapting to the development of new technologies. With the introduction of synchronous digital system, the development of communication has entered a new era. It adapts to the requirements of many new services in modern information society and can give full play to the potential information transmission capability of optical fiber. 1.SDH compared with the characteristics of PDH, which has the following advantages: 1. Provides a unified optical interface in the world, PDH there is no uniform standard in the world, only the regional signal rate and frame structure standards, that is, two major digital systems,