基于因子图模型的水下传感器网络时间同步方法
Time synchronization method for underwater sensor networks based on the factor graph model
孙大军 1欧阳雨洁 1韩云峰 1王泽彧 1刘璐1
作者信息
- 1. 哈尔滨工程大学水声技术全国重点实验室,黑龙江哈尔滨 150001;海洋信息获取与安全工业和信息化部重点实验室(哈尔滨工程大学),黑龙江哈尔滨 150001;哈尔滨工程大学水声工程学院,黑龙江哈尔滨 150001
- 折叠
摘要
为了降低水下传感器时间同步周期长、提高同步效率,本文提出了 一种基于因子图模型的水下位置、声速、时延测量值的参数融合方法.该方法在求解系统钟差边缘概率密度函数后,对该函数进行二进制化简,从而快速解算各传感器钟差,实现网络的动态时间统一.试验结果证明:在其动态时间同步准确度高于8×10-4 s的前提下,其同步周期仅为现有方法的1/2.并可以在一个周期内完成对整个网络的授时.计算量降低.
Abstract
To address the problems of lengthy synchronization and low efficiency in underwater sensor networks,a parameter fusion method based on the factor graph model is proposed in this article for measuring underwater loca-tion,sound speed,and time delay.After calculating the marginal probability density function of system clock bias parameters,it is simplified through binarization;thus,the clock bias parameters of each sensor can be quickly calculated,enabling dynamic time synchronization across the network.Experimental results demonstrate that under the assumption of high synchronization accuracy of larger than 8×10-4 s,the synchronization period is only half the current methods,and the time setting of the entire network can be achieved within one cycle,reducing computa-tional load.
关键词
概率图模型/因子图模型/水下时间同步方法/水下授时/水下传感器网络/和积算法/概率密度函数/全局函数Key words
probabilistic graph model/factor graph model/underwater time synchronization method/underwater timekeeping/underwater sensor network/sum-product algorithm/probability density function/global function引用本文复制引用
基金项目
国家重点研发计划(2021YFC2801300)
黑龙江省自然科学基金(YQ2019D003)
出版年
2023