基于最大似然估计的平均一致性时钟同步改进算法  

Improved Average Consensus Clock Synchronization Algorithm Based on Maximum Likelihood Estimation

作　　者：吕鹏程 张霞[1] 李鸥[1] LYU Pengcheng;ZHANG Xia;LI Ou(Information Engineering University,Zhengzhou 450001,China)

机构地区：[1]信息工程大学,河南郑州450001

出　　处：《信息工程大学学报》2022年第5期537-545,共9页Journal of Information Engineering University

摘　　要：基于一致性原理的时钟同步算法在无人机蜂群系统中有着重要的应用价值。实际中,节点间交互时钟信息的过程存在随机通信时延,将影响算法收敛性。针对这一问题,提出基于最大似然估计的平均一致性时钟同步改进算法。在节点时钟之间同时存在频差与相差条件下,利用相邻节点之间最近一次的时钟交互与前M次的时钟交互对相对时钟斜率做最大似然估计,克服随机时延对时钟同步的不利影响,实现了节点时钟同时存在频差与相差条件下的逻辑时钟同步。仿真结果表明,相较于平均一致性时钟同步算法以及基于最小二乘估计的时钟同步算法,本文所提算法在存在随机通信时延的情况下具有更好的稳定性,且同步精度更高。The clock synchronization algorithm based on consensus has important application value in a drone-swarm system. In practice, there is random communication delay in the process of interactive clock information between nodes, which will affect the convergence of the algorithm. Under the condition that there are both frequency differences and phase differences between node clocks at the same time, the improved time synchronization algorithm based on maximum likelihood estimation is proposed, which uses the current clock interaction and the previous M clock interaction to estimate the relative clock slope in order to overcome the disadvantage of the stochastic time delay, and realize the logic clock synchronization. The simulation results show that compared with average time synchronization algorithm and least square estimation based time synchronization algorithm, the proposed algorithm has better stability and higher synchronization accuracy in the presence of delay and large delay jitter.

关 键 词：时钟同步 一致性 时延网络 最大似然估计 

分 类 号：TN929.52[电子电信—通信与信息系统]