基于ZigBee的无线传感器网络定位算法的研究与设计

发布时间：2018-05-09 00:34

本文选题：无线传感器网络 + 非视距通信　；参考：《兰州交通大学》2017年硕士论文

【摘要】：近年来,无线技术和传感器技术得到了空前发展,人们对相关技术的需求日益高涨,一种新型无线传感器网络技术横空出世。该技术借由传感器节点造价低廉、体积小巧、易于部署等特性,被广泛应用于军事、工业、农业、畜牧业、智能家居、智慧城市等多个领域。尽管这些应用囊括了各行各业且各具特点,但它们具有一个共同点,即需要传感器节点的位置信息。若缺少了传感器节点的位置信息,那么系统获取的一切信息都失去了意义。因而获取节点位置信息的方式尤为重要。长久以来,对传感器位置信息的获取都是通过GPS定位装置完成的。我们知道,应用GPS装置需要消耗大量资金,这并不符合我们对传感器节点廉价的要求。因此,如何控制可定位传感器节点的成本问题是目前的热点话题众多研发机构都致力于开发一种新型传感器节点位置信息获取技术,目前依靠无线传感器网络自身进行定位的方式颇受青睐。该技术的特别之处在于,只需运用节点间的通信信息,采取特殊算法即可确定节点位置,从而完成定位。本文分别介绍了传感器网络定位技术的相关概念、几种定位算法及发展现状,借此分析目前该技术存在的问题,并提出改进方案。(1)辅助定位节点(锚节点)自定位,在传统的无线传感器定位系统中,对于目标节点(标签节点)的定位往往需要借助大量辅助定位节点(锚节点)来实现。但锚节点的位置信息的获取具有两种方式,即通过GPS定位装置获取或人工测量,而这两种方式的缺点是成本过高和定位精度受人工影响大。同时,当系统处于室内环境中时,由于GPS定位精度大大下降,因此可能出现无法定位的情况,这都是目前所面临的问题。为了解决这一问题,本文设计提出了锚节点自定位算法。该算法的核心在于,综合系统已知和可以获取的信息来对未知锚节点进行定位工作,其中系统已知信息是部分锚节点已知的位置信息,可获取的信息为信息到达时间信息和角度信息。借此大大减少了系统需求初始位置信息已知的锚节点数目,在对系统定位精度影响较小的情况下,降低了系统成本,提升了系统适用范围。(2)传感器节点非视距通信。当无线传感器网络应用在室内环境或城市中时,往往会出现一类问题,即传感器节点间信息的传递会受到障碍物阻挡,导致系统无法进行视距通信。这类问题的直接后果是会使我们通过定位节点得到的信息出现较大偏差,降低系统定位性能。针对此类问题,本文提出非视距鉴别算法。算法利用非视距使得部分信息出现较大改变这一特性,从系统中鉴别出无法视距通信的节点,并在定位时去除该节点,从而消除非视距问题对系统定位性能的影响。(3)基于到达时间差的定位算法复杂度高及系统功耗过高的问题。运用传统的TDOA定位算法进行定位时,会遇到定位方程超定非线性问题,此时需要运用迭代法求解。而迭代法的运用,除了提高算法复杂度外,也增加了系统功耗。基于此,本文提出了混合TDOA与AOA的定位算法,结合TDOA与AOA信息,成功将求解迭代定位方程的问题简化,成功降低了算法复杂度,减少了系统功耗。同时,针对于系统功耗高的问题,本文还提出了利用Zigbee协议代替传统的WiFi协议来开发定位系统,借此有效的降低了系统功耗,增加了系统寿命,提升了系统适用范围。通过仿真分析和最终系统的实现,证实了本文算法的有效性,也证明了本文思路的正确性。
[Abstract]:In recent years, wireless technology and sensor technology have been developing unprecedentedly, and the demand for related technologies is increasing. A new wireless sensor network technology has come out. This technology is widely used in military, industry, agriculture, animal husbandry and smart home, which is characterized by low cost, small size and easy deployment of sensor nodes. Although these applications include all walks of life and various characteristics, they have a common point, that is, the location information of the sensor nodes is needed. If the location information of the sensor nodes is missing, all the information obtained by the system is meaningless. Thus, the way to obtain the location information of the node is particularly heavy. For a long time, the acquisition of sensor location information is accomplished through the GPS positioning device. We know that the application of GPS devices requires a large amount of money, which does not conform to the cheap requirements for sensor nodes. Therefore, how to control the cost of locable sensor nodes is a hot topic of research and development institutions at present. To develop a new location information acquisition technology for sensor nodes, it is very popular to rely on the wireless sensor network itself for positioning. The special feature of this technology is that the location of nodes can be determined by using the communication information between nodes, and the location of nodes can be determined by special algorithms. The related concepts of the network positioning technology, several positioning algorithms and the development status, to analyze the problems existing in the present technology and propose an improved scheme. (1) the self positioning of the auxiliary positioning node (anchor node), in the traditional wireless sensor positioning system, the location of the target node (tag node) often needs a large number of auxiliary positioning. There are two ways to obtain the location information of the anchor nodes, namely, through the GPS positioning device or manual measurement, and the disadvantages of the two methods are high cost and high positioning accuracy. At the same time, when the system is in the indoor environment, the positioning accuracy of the GPS is greatly reduced, so it may appear. In order to solve this problem, in order to solve this problem, a self positioning algorithm of anchor nodes is proposed in this paper. The core of this algorithm is that the information of the integrated system is known and can be obtained to locate the unknown anchor nodes, and the known information is the known location information of some anchor nodes. The available information is the information of the arrival time and the angle of information. This greatly reduces the number of anchor nodes known in the initial position information of the system, reduces the system cost and improves the application scope of the system when it has little influence on the positioning accuracy of the system. (2) the sensor node is non sight distance communication. When used in the indoor environment or in the city, there is often a kind of problem, that is, the transmission of information between sensor nodes will be blocked by the obstacle, which leads to the system unable to carry out the sight distance communication. The direct consequence of this kind of problem is that the information that we get through the location node will be large deviation and reduce the system location performance. For such problems, In this paper, a non sight distance identification algorithm is proposed. The algorithm uses the non sight distance to make a large change in the partial information, and identifies the nodes that can not be seen in the sight distance from the system, and removes the node in the location, thus eliminating the influence of the non sight distance on the system location performance. (3) the location algorithm based on the time difference of arrival time is highly complex and the system has a high degree of complexity. The problem of high power consumption is that when using the traditional TDOA positioning algorithm, the problem of the location equation overdetermined nonlinear will be encountered, and the iterative method is needed at this time. In addition to improving the complexity of the algorithm, the application of the iterative method also increases the power consumption of the system. Based on this, this paper proposes a positioning algorithm of mixed TDOA and AOA, combined with TDOA and AO. A information has succeeded in simplifying the problem of solving iterative location equations, reducing the complexity of the algorithm and reducing the power consumption of the system. At the same time, in view of the problem of high system power consumption, this paper also proposed the use of the Zigbee protocol instead of the traditional WiFi protocol to develop the positioning system, which can effectively reduce the power consumption of the system, increase the life of the system, and improve the system life. The validity of the algorithm is verified by simulation analysis and the realization of the final system. It also proves the correctness of the thought in this paper.

【学位授予单位】：兰州交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN92;TP212.9

【参考文献】