【作者】 郭昀；

【导师】 罗风光； 罗志祥；

【作者基本信息】 华中科技大学 ， 物理电子学， 2007， 硕士

【摘要】 无线传感器网络的研究和发展使得其应用越来越广泛。在人类不宜到达的环境中部署传感器节点,实现对环境的监测是无线传感器网络的一个重要应用,在军事和民用领域都有着深远的意义。节点定位技术是无线传感器网络的关键技术之一。本文介绍了现有的无线传感器网络节点定位系统和算法,分析了各种算法的优缺点,在DV-Hop算法的基础上提出一种新的距离无关的节点定位算法,并进行了算法在三维空间中的推广。传感器节点的硬件设计使其具有可以调节的通信半径。在满足通信连通度的前提下应尽量减少单跳通信距离,减少能量损耗。采用最大通信半径时,监测区域内大部分节点都能够直接和信标节点进行“握手”,并记录此时的通信半径。统计信标节点的邻居节点数目,逐步缩小通信半径,使邻居节点数目达到理想值。各个节点转发信标节点的分组信息,并通过公式计算与信标节点之间的距离,最后,用极大似然法确定节点的位置坐标。本算法中采用信标节点通信半径和跳段数公式计算两种方法比较来确定节点之间的距离,能够将误差控制在一定范围内。采用100个传感器节点,在不同的覆盖范围和信标节点密度下进行软件仿真。比较仿真结果,得到最佳的定位条件。在该条件下,本算法的定位精度比DV-Hop算法定位精度高,可以满足应用需要。更多还原

【Abstract】 Study and development of Wireless Sensor Networks (WSN), have been proposed for a multitude of diverse applications. One of the most important applications is monitoring the environment which is dangerous and hardship for human. It has much meaning in the military and civilian fields.Self-localization technology is one of the most important technologies of Wireless Sensor Networks. In this thesis, self-localization systems and algorithms in existence of WSN are introduced and analyzed. Then a new kind of range free self-localization algorithm is developed based on DV-Hop algorithm. And a self-localization algorithm is promoted in 3D space.Communication radius of sensor nodes can be adjusted by hardware design. Under the premise of ensuring network connectivity, the smallest radius of communication is used to reduce communication energy. When maximum radius is used, most nodes of the monitoring space can have“handshake”with the beacon node. And this radius is recorded. Count the number of beacon node’s neighbor nodes. If the number is too big, narrowing the communication radius gradually, until the number is proper. Sensor nodes transmit beacon node information, and then compute the distances between sensor nodes with formula. Finally coordinates of unknown sensor nodes are computed. In the algorithm there are two methods to compute distances between beacon nodes and unknown nodes. One is beacon node communication radius, and the other is using hop distances to compute. Compare tow results, error can be control in a certain range.100 sensor nodes are used in the computer simulation by software. Compare simulation results, which are got in different coverage and density beacon nodes, to get the best localization conditions. In this condition, accuracy of this algorithm is higher than DV-Hop algorithm. It can meet application needs.更多还原