【作者】 孟丽莎；

【导师】 金仁成；

【作者基本信息】 大连理工大学 ， 机械电子工程， 2012， 硕士

【摘要】 无线传感器网络(Wireless Sensor Network,WSN)融合了计算机、微机电、通信和传感器等多领域技术,是极有潜力的研究方向。无线传感器网络由数量众多的传感器节点构成,节点在感知信号的同时需要获取自身位置信息,从而感知的数据才具有实际意义,确定传感器节点位置的技术称为定位技术,是无线传感器网络的关键技术之一。本文主要研究无线传感器网络基于测距的定位技术,并提出自己的求精定位算法。常用的测距技术有四种,在综合考虑传感器节点体积、功耗、成本等因素的基础上,采用RSSI(接收信号强度指示)技术作为节点间的距离测量方法,并通过实验建立起基于RSSI的测距模型。本文提出两种新的求精定位算法,这两种定位算法都依靠测距技术,并需要对信标节点进行定位,通过估算的信标节点位置对未知节点位置进行补偿求精。第一种算法为混合定位求精算法,先采用MAX-MIN算法初次定位,距离补偿之后采用极大似然估计法进行二次定位,可以提高算法的定位精度。第二种算法为位置修正求精定位算法,在初步估算未知节点位置之后,对未知节点坐标位置进行补偿,改善算法定位精度。仿真实验与室外实验证明,这两种求精定位算法在不增加额外硬件设备的条件下,提高了无线传感器网络的定位精度。本文最后通过仿真实验讨论了信标节点密度、通信半径和网络区域面积对定位算法的影响,这些参数在一定范围内变化,可以得出结论：信标节点密度越大、通信半径越大、网络区域面积越小,传感器节点的定位算法精度越高。更多还原

【Abstract】 Wireless sensor networks (WSNs), which integrate technologies of computer, micro-electro-mechanism, communication and sensor, is a potential research field. The wireless sensor networks consist of a large number of sensor nodes. When the sensor nodes sense the environment around, they need to know their own position to make the sensing signal useful. To locate the sensor nodes is called localization technology, which is one of the key technologies in wireless sensor networks.The paper researched on the localization technology ranging-based in wireless sensor networks and presented new refinement algorithm. There are four kinds of common ranging technology. After comprehensive consideration of cubage, power-consumption and cost of the sensor nodes, RSSI (Receive Signal Strength Indication) technology is used to measure distance between nodes. The distance-RSSI model is set up through experiments.Two new refinement algorithms are presented in the paper. Both of them are based on the ranging technology and need to locate their anchor nodes. The estimated position of the anchor nodes is used to compensate and refine the position of the unknown nodes. One is called hybrid localization-refined algorithm. To locate the unknown nodes using MAX-MIN algorithm first, then to locate them the second time using Maximum Likelihood Estimation algorithm (MLE) after distance compensation. The strategy improves the localization precision. Another one is called position-corrected refinement algorithm. After locating the unknown nodes, to compensate the position is done to increase the localization precision. The simulation and outdoor experiments show that the two refinement algorithms improve the localization precision without additional equipments.Finally, the effect of the anchor node density, the communication radius and the area of network for the localization algorithm is discussed through simulation experiments. To control these parameters in some scope, if the more the anchor node density and the communication radius are and the smaller the area of network is, then the higher the localization precision of the sensor nodes is.更多还原