关于SDH数字系统抖动和漂移测量仪表的新建议

New Recommendations for Jitter and Shift Measuring Instruments of SDH Digital System

１９９９年３月，ＩＴＵ公布了Ｏ．１７２对建议。它全面、详细地规范了ＳＤＮ系统抖动、漂移测量仪表的性能。Ｏ．１７２建议主要规定了仪表的测量接口及其指标，抖动、漂移产生能力，抖动测量范围，漂移测量功能。该建议规范了仪表在ＳＤＨ各速率上测量抖动和漂移的特性，并在Ｏ．１７１的基础上对ＳＤＨ传输系统的各 ＰＤＨ速率支路抖动测量特性作了补充。文章介绍了Ｏ．１７２建议的影响。

The jitter and shift parameters' measuring is very important to SDH systems. Before 1999, only ITU--T O.171 specifies the Performance of jitter mea- suring instruments for PDH systems, while there is no formal specifications to define the performance of jitter and shift measuring instruments for SDH. In March 1999, ITU publishes O.172 recommendation to comprehensively define the Performance of SDH sys- tems' jitter and shift measuring instruments. O.172 defines the instruments' features to measure jitter and shift over various SDH rates and complements the PDH ─rate tributaries' jitter measuring characteristics of SDH transmission system based on O.171. The influence of O.172 is also introduced in this paper.