一种基于平均场的无线自组织网络时钟同步方法  

A Clock Synchronization Method for Ad Hoc Networks Based on Mean Field

作　　者：陈旿[1] 孙建华[1] 高小杰[1] 李胆胆 左颖[1] 洪亮[1] 

机构地区：[1]西北工业大学自动化学院,西安710072

出　　处：《计算机学报》2016年第5期893-904,共12页Chinese Journal of Computers

基　　金：西北工业大学基础研究基金(NPU-FFR-20110045)资助~~

摘　　要：时钟同步是无线自组织网络的一项重要支撑技术,是协议运行、节能管理、数据融合和协同工作的必要前提.文中首先给出了无线自组织网络中节点之间时钟偏差的特性分析,并设计了卡尔曼滤波器,用于精确地估计邻居节点之间的时钟偏差.然后提出了一种基于平均场的全分布式多跳时钟同步方法.该方法不维护特殊节点,基于平均场理论,通过节点之间的共同作用建立虚拟时钟基准;将节点之间的时钟偏差映射为团势能,在此基础上建立了基于伊辛模型能量函数描述的全网时钟同步平均场模型;最后,采用并行能量最小化的方法实现全网时钟分布式同步.仿真结果表明所提出的解决方案可以实现高精度的全局时钟同步,并且具有低开销、快速收敛、健壮、可扩展的特点.Precise clock synchronization is a critical fundamental technology of Ad Hoc networks.It is a necessary premise of protocol operation,energy management,data aggregation and collaborative work.In this paper,firstly,the property of clock offset is analyzed.A Kalman filter is designed to estimate clock offset precisely.Then,a fully distributed multi-hop synchroni-zation solution is proposed.No special node needs to be maintained in the solution,and a virtual reference clock is gotten by an averaged effect of neighbor nodes using mean field theory.A mean field model for global network clock synchronization based on the energy of Ising model is established by mapping clock offset to clique potential.Finally,a parallel energy minimization is adopted to get global clock distributed synchronization.The simulation result shows that the proposed solution can obtain a high-precision clock synchronization of the whole network and has the virtue of low overhead,fast convergence,robust and scalable.

关 键 词：时钟同步 卡尔曼滤波器 平均场 团势能 伊辛模型 能量最小化 物联网 车联网 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]