面向信息物理系统的无线传感器网络定位误差研究

【作者】 李煜；

【导师】 张晶；

【作者基本信息】 昆明理工大学 ， 电子与通信工程（专业学位）， 2022， 硕士

【摘要】 信息物理系统(Cyber-physical system,CPS)作为一种将信息世界与物理世界连接的重要手段,得到了广泛的应用。而无线传感器网络作为信息物理系统的重要感知网络,是由许多小型的节点设备组成的监测网络,主要目的是用于实现人们对于该物理区域的远程监控,以获取人们所需要的各种信息,实现信息物理之间的交互。其中,在大多数的信息物理交互应用场景中,人们在获取其感知信息的同时,更关心其发生事件的具体二维及其三维物理位置信息,为此,对传感器节点的位置信息进行定位是其应用的重要内容,而无需测距的DV-Hop由于其适用于大规模信息物理传感网络且对节点要求低的优点得到了广泛的应用,传统DV-Hop是对处于二维层面的位置进行估算,并且其计算所得坐标差距较大,故需对其进行改进研究,对于实际的三维空间中的定位问题,需要将DV-Hop定位算法提升至三维层面,并对其误差进行改进研究,以适应信息物理传感网的需要,为此,本文将主要针对这些方面的问题进行优化改进:1、针对传统DV-Hop在信息物理系统应用场景中的所得位置差距较大的现象,从其定位的特点出发,总结出改进的三次修正DV-Hop,该算法依据二维多通信半径的二次修正的方式对节点之间的跳数进行优化,从而使得跳数的估计更加准确,其次采用平方代价函数的形式对跳距进行计算,使得总体误差最小化的同时,各项误差也达到最小值,并引入跳数-距离匹配策略对跳距进行加权计算,随后,通过优化的跳数、跳距对未知节点和锚节点定位,未知节点根据锚节点的误差值进行修正,随后将该修正坐标采用作为泰勒展开点进行更加细致的优化,最后,采用场景限制条件对该计算坐标不符合实际场景的坐标进行限制,从而使得定位坐标值更加准确。2、针对实际场景为三维空间的信息物理系统应用场景情况,提出三维DV-Hop并对其进行改进优化,由于传统三维算法的最小二乘与各改进算法的三维双曲线及加权最小二乘的误差仍然改善较小的情况,总结出改进的无约束优化三维DV-Hop,首先采用二通信半径策略将跳数优化处理,以获取更准确的节点之间的跳数值,其次采用三维平方代价函数对跳距进行计算,降低了节点跳距计算的误差,并对于未知节点与多个锚节点相邻的情况,引入加权计算的思想优化其跳距值,最后将分离的加权误差最小化约束优化问题,采用Lagrangian乘子法的思想转化为无约束方程并进行求解计算,从而使得该算法的定位误差得到了显著降低。3、针对三维信息物理系统场景下,精度要求比较高的场合,总结出改进鲸鱼的三维DV-Hop,该算法采用三维多通信半径的划分策略对节点之间的跳数进行了更细致的优化,使得跳数的估计更加准确,随后采用平方代价函数对跳距进行计算,并将跳距所计算出的估计距离与实际距离的平均差值作为跳距的补偿值,对跳距进行了进一步的修正,随后以最小二乘的未知节点定位坐标为中心,通信半径的一半为轴距,建立三维立方体解空间,并对该立方体解空间进行场景限制,进一步修正其解空间的范围,采用量子球面初始化、柯西逆累计函数和贪婪的偶次随机反向学习策略对鲸鱼算法进行改进,得出解空间的高精度解,实验证明该算法在定位的相对误差与绝对误差方面值均为最小,满足精度需求高的场合的需要。更多还原

【Abstract】 Cyber-physical system(CPS),as an important means to connect the information world with the physical world,has been widely used.Wireless sensor network,as an important perception network of information physical system,is a monitoring network composed of many small node devices.The main purpose is to realize the remote monitoring of the physical area,to obtain all kinds of information needed by people,and to realize the interaction between information physics.In most of the application scenarios of physical interaction of information,people are more concerned about the specific two-dimensional and three-dimensional physical location information of the event when they get their perception information.Therefore,positioning the location information of sensor nodes is an important content of its application.Without range of DV-Hop because of its suitable for large-scale physical sensing information networks,and the advantage of low demands on node has been widely used,traditional DV-Hop is to estimate in the two-dimensional plane position coordinates and its computation income gap is larger,so the need to improve research,for the actual location problem in 3D space,DV-Hop localization algorithm needs to be promoted to the three-dimensional level and its error is improved to meet the needs of information physical sensor network.Therefore,this dissertation will mainly optimize and improve the problems in these aspects:1.Aiming at the phenomenon that the traditional DV-Hop has a large gap in the application scene of information physics system,based on the characteristics of its localization,the improved three times modified DV-Hop is summarized.The algorithm optimizes the hop number between nodes according to the second modification method of two-dimensional multi-communication radius,so as to make the hop number estimation more accurate.Second in the form of square cost function for calculation,jump from minimize the overall error at the same time,the error is at the minimum,and introduce the hop-weighted distance matching strategy to jump from,then,through the optimization of the hop,jump from the unknown node and anchor node localization,the unknown node based on the error value of anchor nodes,Then,the modified coordinate is used as Taylor expansion point for more detailed optimization.Finally,the scene restriction condition is used to limit the coordinates that the calculated coordinates do not conform to the actual scene,so that the positioning coordinate value is more accurate.2.Aiming at the application scenario of information physics system where the actual scene is three-dimensional space,the 3D DV-Hop is proposed and improved.Since the errors of the traditional 3D algorithm and the 3d hyperbola and weighted least squares of the improved algorithms are still improved,the improved unconstrained optimization 3D DV-Hop is summarized.First of all,radius of two communication strategy will hop optimization,in order to get more accurate jump value between nodes,secondly using three-dimensional square cost function for calculation,jump from reduces the nodes to jump from the error of calculation,and in the case of the unknown node and multiple anchor nodes adjacent,introducing the idea of weighted optimization from the jump value,Finally,the separation of the weighted error minimization constraint optimization problem is transformed into an unconstrained equation by Lagrangian multiplier method,and the positioning error of the algorithm is significantly reduced.3.Aiming at the high precision requirement of 3D information physical system,the improved whale 3D DV-Hop is summarized.The algorithm uses the division strategy of three-dimensional multi-communication radius to optimize the hop number between nodes more carefully,which makes the hop number estimation more accurate.Then,the square cost function is used to calculate the hop distance.And will jump from the estimated distance calculated by the average difference between the actual distance and value as the compensation value of the jump distance,has carried on the further revised to jump from,then at least squares of the unknown node location coordinates as the center,communication radius was half the wheelbase,set up 3D cube solution space,and scenes of the cube solution space limit,further modified the scope of the solution space,Quantum spherical initialization,Cauchy inverse accumulative function and greedy even random reverse learning strategy are used to improve the whale algorithm,and the high-precision solution of the solution space is obtained.Experiments show that the algorithm has minimum relative error and absolute error,which can meet the needs of high precision situations.更多还原