【作者】 薛波；

【导师】 包振山；

【作者基本信息】 北京工业大学 ， 计算机科学与技术， 2014， 硕士

【摘要】 嵌入式系统、传感器技术、无线通信技术的日益成熟推动了无线传感器网络时代的到来。作为一种新型的网络，方便的网络部署、独特的组网方式以及以数据为中心的特点使无线传感器网络在军事、科研、农业、工业、医药等领域表现出潜在的应用价值和巨大的经济效益，受到各国科研机构广泛的关注和研究。本文首先介绍了无线传感器网络的系统结构，总结了网络设计的性能评价指标，简单阐述了无线传感器网络在不同领域的应用。然后概括性介绍了部分经典的无线传感器网络路由协议，并分析了它们的优缺点。在LEACH算法基础上，提出两种新的改进策略：1. LEACH算法随机选取簇头，容易出现分簇不合理现象，在网络节点分布不均匀时尤为显著。针对该情况提出基于K-means聚类分簇的LEACH改进算法，在网络初始时刻采用K-means算法将节点预先分类，位置相近的节点被分为一类，簇头节点从同类节点中优选获得。2. LEACH算法中簇头节点与基站以单跳方式通信，长距离数据传输消耗了簇头节点大量的能量，考虑在簇头与基站之间建立多跳路由，提出基于LEACH的层次树路由协议HT-LEACH，在簇头和基站之间建立以基站为树根的层次树路由，数据沿树干多跳传输给基站。文中通过仿真对比，评估了改进算法的性能。对于采用K-means聚类分簇的LEACH改进算法，经过聚类方式分簇，不合理分簇现象明显减少，网络性能有所改善，且在不均匀网络中效果显著。对于改进算法HT-LEACH，簇头节点通过多跳转发和数据融合的方式，降低了簇头节点的能量消耗，延长了网络生命周期。更多还原

【Abstract】 With the increasingly mature development of embedded systems, sensor technology and wireless communication technology, wireless sensor network(WSN) era has arrived. As a new type network with easy network deployment, unique networking and data-centric, wireless sensor network shows potential application value and huge economic benefit in the fields of military, scientific research, agriculture, industry and medicine. Now it has been paid more attention and wildly researched by national institutions.This paper describes the architecture of wireless sensor network, summarizes the performance evaluation of network design and introduces applications in different fields. Then some classical routing protocols are briefly described and the strength and weakness are analyzed. After that, we propose two improved strategies based on LEACH algorithm:1. In LEACH, the cluster head random selection lead to unreasonable clustering. This case will increase in uneven distributed network. We propose an improved LEACH algorithm based on K-means in clustering, which use K-means algorithm to cluster nodes at the beginning of network working. The nodes are divided into several parts by position and the cluster head is selected optimally in certain part.2. Another reality in LEACH is that the cluster heads communicate with the base station by single-hop. Long communication distance will lead to more energy consumption. Thus, a hierarchy tree routing algorithm based on LEACH (HT-LEACH) is proposed, which build a hierarchy tree between cluster heads and base station. The data transmits to base station by multi-hop using tree routing.We evaluate the improved algorithm by the simulation experiment. For the improved LEACH algorithm based on K-means in clustering, unreasonable clustering phenomenon has been decreased and network lifetime is prolonged. What’s more, it is more significant on uneven distributed network. For the hierarchy tree routing based on LEACH(HT-LEACH), the cluster heads consume less energy through building hierarchy tree routing between cluster heads and the base station and data fusion. The network also shows better performance.更多还原