基于卡尔曼滤波的 TDM网络时钟同步方法研究

摘要

网络时钟同步是TDM网络中必须要考虑的关键问题，其中采用IEEE1588时钟同步协议的软件同步方法在高精度同步场合应用广泛。如果时钟同步过程中链路不对称会引入时间数据偏差问题，采用同步补偿的方法从一定程度上改进了时间同步精度，但该类方法没有考虑环境噪声的问题，容易造成TDM网络不稳定。本文提出一种基于卡尔曼滤波的TDM网络时间间接补偿方法，对时钟同步获取的信息先进行卡尔曼滤波降噪处理，然后再通过频率调整进行时间间接补偿，在提高同步精度的同时，提升了TDM网络的稳定性。%The important issue of the TDM network is precise time synchronization. The software syn-chronization method using the IEEE1588 clock synchronization protocol is widely used in the high precision synchronization. If the link of the time synchronization process is asymmetrical,it will introduce time data deviation. Using synchronous compensation method will improve time accuracy to a certain extent,but this method does not consider the problem of environmental noise which is easy to cause the network system in-stability. This paper presents a method of TDM network clock indirect compensation based on Kalman fil-ter. The information of the time synchronization is firstly denoised by Kalman filter,then clock is adjusted by the frequency indirectly to compensate the time. This method can both improve the time synchronous ac-curacy and enhance the stability of TDM network.