摘要
简要介绍了微波通信中准同步数字系列（ＰＤＨ）和同步数字系列（ＳＤＨ）的基本原理，对ＰＤＨ和ＳＤＨ在比特速率、帧结构、信号复／分接、频率配置、接口与网络管理功能等方面进行了比较，得出了ＳＤＨ明显优于ＰＤＨ的结论。
The article introduces the basic principle of PDH and SDH in the microwave communication. It also compares the bit rate, frame structure, signal multiplex/demultiplex, frequency configuration, interface and network management function of PDH with that of SDH, gets conclusion that SDH is better than PDH.
作者
张之敏
ZHANG Zhi_min(Microwave Station of Tianjin Toll Communication Bureau, Tianjin 300052, China)
