【作者】 赵相鹏；

【导师】 张华忠；

【作者基本信息】 山东大学 ， 计算机应用技术， 2009， 硕士

【摘要】 无线传感器网络是近年来最有发展前景的技术之一,它集中了微机电技术、嵌入式计算技术、分布式信息处理技术和无线通信技术,是一种全新的信息获取和处理模式。节点定位、拓扑控制、路由协议等是无线传感器网络研究中的几个基本问题,其中节点定位问题是无线传感器网络进行目标识别、监控、跟踪等众多应用的前提,而且无线传感器网络的某些路由机制、覆盖信息、负载均衡和拓扑控制等都依赖于节点位置信息。因此,针对无线传感器网络节点自身定位技术的研究具有重要的理论与实际意义,是无线传感器网络研究中的热点问题之一。由于传感器节点受体积、成本、能量等因素的限制,而且通常工作在人类难以或不宜接近的场合,因此传统的无线网络定位方式有许多不适合无线传感器网络的地方,需要专门设计适合无线传感器网络的定位技术。本文在阐述了无线传感器网络的体系结构、自身特点和应用领域的基础上,对无线传感器网络的定位技术展开了深入分析。通过对现有定位算法的总结,综合无线传感器网络的特点和定位需求,本文提出了一种基于RSSI测距的节点定位算法——LABOR,LABOR算法引入高级节点担任信标节点,它们具有充足的能量及较大的发射功率,其无线射程可以覆盖整个网络。LABOR算法改变了以往算法中节点被动接收信标节点周期性发送的定位信息的方法,而是由那些有定位需要的节点主动发出请求,信标节点协同对定位请求进行处理,最后节点采用算法引入的Monte Carlo方法对位置进行计算。由于只对有定位需求的部分节点进行定位,简单易实现,通信次数少,从总体上降低了网络中普通节点的能量消耗,延长了网络生存周期。此外,本文提出的算法通过设定测距修正权值、优选信标节点等措施,较以往的算法提高了定位精度。最后,本文针对不同的网络部署情况在MATLAB中对LABOR算法进行了仿真实验。实验结果表明,LABOR算法是一个稳健的定位算法,适合随机布置的网络,具有很强的扩展性。更多还原

【Abstract】 Wireless Sensor Networks (WSN) is becoming one of the most promising technologies in recent years. It is a new pattern of information gathering and processing which integrates technologies of micro-electro-mechanism, embedded computing, distributed information processing and wireless communication. Node localization, topology control, routing protocols are some of the fundamental problems of WSN. Among these problems, node localization has been focused as a basic factor for that it is the precondition of many applications of WSN, such as target identification, surveillance and tracking. Furthermore, some routing schemes, information of network coverage, load balance, topology control of WSN depend on the location information of the nodes in networks. So, the study for node localization of WSN possesses great significance in the theory and practice, and it will become an important part in the research area.Since the nodes are restricted by size, cost and energy, and WSN always works in the environment which is hard to be accessed, the traditional localization methods of wireless networks can’t fit the WSN well. The special localization technologies should be designed for WSN. This paper expounds the system architecture, features and applied fields of WSN. Based on this, it thoroughly analyzes the localization technologies of WSN.As summarizes the existing localization algorithms and compounds the features of WSN and localization request, this paper proposes a localization algorithm based on RSSI (LABOR). The algorithm adds advanced nodes to be beacon nodes in order to assist in localization. The advanced nodes have enough energy and large radio power. Their communication fields can ranges the whole WSN. LABOR changes the method that the nodes receive localization information passively. In this algorithm, nodes which need to be localized send requests actively. The beacon nodes process the requests cooperatively. At last, nodes use Monte Carlo method to estimate their positions. Because of just localizing some nodes which have requests, the algorithm is easy to use. It has fewer communication packages, so it lessens the energy consumption of the whole nodes and extends the living life of WSN. Furthermore, the algorithm in this paper raises localization accuracy by setting range emendation weight and select beacon nodes optimizingly.In the end, this paper simulates the algorithm in MATLAB for different network deployments. The simulation result shows that LABOR is a robust algorithm. It is suitable and extendable for randomly-deployed WSN.更多还原