SDH系统E1接口定时的高质量恢复

SDH传输网中由指针调整带来的低频抖动和漂移已经成为SDH传输网与其它传输网互通的障碍.这一问题可以通过在SDH系统的边界支路输出口处采用极低带宽的锁相环对SDH网络指针调整带来的抖动和漂移进行平滑来得到改善和解决.本文介绍了一种捕捉速度快、带宽窄、适合于多支路大规模集成的用于SDH系统E1支路接口的二阶全数字锁相环路.

Sliding Adaptive Mode Control Based on Fuzzy Neural Networks for Nonlinear Systems Represented by Input-Output Models

Low frequency jitters and wanders caused by pointer adjustments in SDH networks have been found to be a big obstacle for the interconnection between SDH and non-SDH networks.This problem can be solved or improved by using a very narrow bandwidth Phase-Locked Loop for jitter and wander suppression at the output tributary interface in SDH systems.An all digital Phase-Locked Loop characterized with a very narrow bandwidth and a wide frequency capture range is presented in this paper.With a simple structure,this PLL is quite feasible for multi-PLL integration for E1 interfaces in an SDH system.