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1.
时空Top-k查询是TMWSNs(双层移动无线传感网)中的一类重要查询.在敌对环境中,攻击者易通过捕获TMWSNs中的关键节点来破坏时空Top-k查询的数据完整性.提出一种确保数据完整性的时空Top-k查询处理协议VIP-TQ.该协议利用虚拟化节点技术与绑定加密技术通过构建传感器节点的数据预处理方法、数据存储节点的时空Top-k查询处理方法以及Sink端的数据完整性验证方法来实现TMWSNs中时空Top-k查询的数据完整性保护.理论分析和实验结果显示,VIP-TQ能够以100%的概率侦测出不完整的时空Top-k查询结果,并具有相对已有方案更高的能效性.  相似文献   

2.
本文对无线传感器网络概念,定位原理,典型定位算法进行阐述,研究几种重要定位技术,对各种算法进行性能分析和比较。  相似文献   

3.
Power saving and query processing are two major concerns in a wireless sensor network. Each of these two issues has been intensively studied separately in the literature. In this work, we are interested in linking the asynchronous power-saving protocol and the continuous query-processing problem together. A cross-layer solution is proposed. On the MAC layer, we propose to use the grid-quorum system (Tseng et al., Computer Networks, 43(3):317–337, 2003) to serve as the underlying power-saving framework. On the network layer, we propose to find query paths based on the power cost incurred by grid quorums used by nodes along a path. We show how these two layers interwork with each other to support continuous queries in an energy-efficient way.  相似文献   

4.
皮兴宇  于宏毅  张延军 《现代雷达》2006,28(10):46-48,52
节点定位是无线传感器网络的一个重要研究内容。针对传感器网络内所有节点物理位置都未知的情况,文中提出一种利用已知的外界参考信号源来对网络内传感器节点进行定位的方法,并建立了基于TDOA、TOA及AOA的定位估计模型。尽管参数测量有误差,但所提出的方法能够提供有效的位置信息及一定的精度,而且基于AOA的定位模型并不增加传感器节点的成本和复杂度。仿真实验结果表明,该方法能对节点进行有效的定位。  相似文献   

5.
In this paper, localization problem in wireless sensor and actor networks (WSAN) is addressed. In WSAN, the performance of event detection and tracking highly depends on the exact location information of the events that must be reported along with the event features. Having precise location information of the sensor nodes, actors are able to execute actions more effectively in the region of detected events. In this context, the accurate localization of sensor nodes is essential with respect to the actors. Particularly, the problem becomes much more complicated when the sensor nodes as well as the anchor nodes (actors) are mobile. In order to localize the mobile sensor nodes relative to the actors, a novel Timing-based Mobile Sensor Localization (TMSL) algorithm is introduced. In TMSL, sensor nodes determine their distance from actors by using propagation time and speed of RF signal. In order to determine distance from the actors, actors actively broadcast reference beacons in a pattern of intervals adaptively defined according to the mobility of sensor nodes and the required level of localization accuracy. These reference beacons carry the interval numbers in which they were transmitted. The interval numbers are then used by the sensor nodes to calculate the start time of the beacons locally which is then used to determine the propagation time. TMSL does neither require nor assume any time synchronization among the sensor nodes or with the actors. Performance evaluations clearly show that TMSL is adaptive to velocity of mobile sensor and actor nodes and can be configured according to the required localization accuracy in order to avoid overhead raised due to high velocity.  相似文献   

6.
Handling high rate queries have always posed a challenge in wireless sensor networks (WSNs) owing to their resource constrained nature. This paper proposes a scheme that performs centralized and distributed optimization to improve the scalability of the high rate spatio-temporal queries in WSNs. Queries are optimized centrally based on multiple criteria such as spatial topological relationships, temporal and attribute correlations. An energy efficient load balanced clustered tree routing based on minimum bounding rectangle spatial indexing scheme is employed to aid the in-network optimization of queries. Two algorithms have been proposed to carry out a centralized and distributed optimization that works adaptively on queries switching between optimal and sub-optimal modes to handle multiple concurrent queries reliably. Simulation results show that the proposed scheme is highly scalable for large scale spatio-temporal queries and also has the added advantage of minimizing the energy consumption due to query and data transmission.  相似文献   

7.
移动无线传感器网络(MWSN)是一种全新的信息获取和处理技术,可以在广泛的应用领域内实现复杂的大规模监测和追踪任务,而移动节点的位置信息则是其应用的基础。针对这一特征,文章深入探讨了移动节点自定位算法的研究现状,介绍了移动无线传感器网络节点定位的基本方法,讨论了定位算法的性能评价指标,并对各种算法性能进行了比较,最后指出了算法存在的问题和解决办法。文章认为三维全节点移动的定位算法将成为以后的研究趋势。  相似文献   

8.
王妮  蒋铃鸽 《通信技术》2009,42(9):127-129
文中在MCB(Monte—Carlo Localization Boxed)定位算法的基础上提出了一种新的移动无线传感器网络(Mobile Wireless Sensor Networks)节点的定位算法——权重MCB算法。MCB算法在定位过程中,在采样和滤波阶段用到了一阶锚节点和二阶锚节点的位置信息,而没有应用到邻居节点的位置信息。权重MCB在定位过程中不仅用到了一阶锚节点和二阶锚节点的位置信息,还应用到了一阶邻居节点的采样集合里的采样点(即一阶邻居节点的估计位置),从而改进了定位精度。对比MCB算法,权重MCB算法对定位精度的改进为13%~18%。  相似文献   

9.
军事防御、灾害监测与救援等危险/恶劣环境监测是无线传感器网络的典型应用。在此面向危险/恶劣环境监测需求,设计并构建移动多Sink无线传感器网络监测系统,实现环境信息感知、便携式移动指挥、事件定位、移动用户生理监护、多模态(语音、图像、文字等)交互等功能。实验测试结果表明,当网络中存在2个移动Sink节点时,网络平均延时小于100 ms,网络丢包率小于6%,可满足网络实时性要求不高的应用。  相似文献   

10.
Rendezvous Planning in Wireless Sensor Networks with Mobile Elements   总被引:1,自引:0,他引:1  
Recent research shows that significant energy saving can be achieved in wireless sensor networks by using mobile elements (MEs) capable of carrying data mechanically. However, the low movement speed of MEs hinders their use in data-intensive sensing applications with temporal constraints. To address this issue, we propose a rendezvous-based approach in which a subset of nodes serve as the rendezvous points (RPs) that buffer data originated from sources and transfer to MEs when they arrive. RPs enable MEs to collect a large volume of data at a time without traveling long distances, which can achieve a desirable balance between network energy saving and data collection delay. We develop two rendezvous planning algorithms, RP-CP and RP-UG. RP-CP finds the optimal RPs when MEs move along the data routing tree while RP-UG greedily chooses the RPs with maximum energy saving to travel distance ratios. We design the Rendezvous-based Data Collection protocol that facilitates reliable data transfers from RPs to MEs in presence of significant unexpected delays in ME movement and network communication. Our approach is validated through extensive simulations.  相似文献   

11.
以往无线传感器网络中的媒体接入控制协议主要针对静止网络。当存在移动节点时。协议性能会大幅度降低。对存在移动节点的无线传感器网络中的媒体接入控制协议进行了性能分析,提出了改进算法。仿真结果验证了算法的有效性。最后给出了一种适合移动节点较多的场景的无线传感器网络媒体接入控制协议。  相似文献   

12.

Geographic routing for realistic conditions is often permeated with localization errors resulting in poor performance and high energy consumption. We propose a simple yet novel geographic routing method to accomplish routing in the presence of location and channel errors. In this algorithm, it is proposed that next hop node is selected based on the combined probability of distance, estimated location error and estimated channel access probability associated with neighbor nodes. The metrics observed for performance were the successful packet delivery rate and the energy consumed. Our algorithms performance is better compared to greedy forwarding techniques of algorithms such as Greedy routing scheme (GRS) and geographic random forwarding (GeRaF). Simulations show the throughput for our algorithm is better compared to others along with reducing the energy wasted on lost packets.

  相似文献   

13.

Many application domains require that sensor node to be deployed in harsh or hostile environments, such as active volcano area tracking endangered species, etc. making these nodes more prone to failures. The most challenging problem is monitoring the illegal movement within the sensor networks. Attacker prefers mobile malicious node because by making the diversity of path intruder maximize his impact. The emerging technology of sensor network expected Intrusion detection technique for a dynamic environment. In this paper, a defective mechanism based on three-step negotiation is performed for identifying the mobile malicious node using the mobile agent. In many approaches, the multi-mobile agents are used to collect the data from all the sensor nodes after verification. But it is inefficient to verify all the sensor nodes (SNs) in the network, because of mobility, energy consumption, and high delay. In the proposed system this can be solved by grouping sensor nodes into clusters and a single mobile agent performs verification only with all the cluster heads instead of verifying all the SNs. The simulation result shows the proposed system shows a better result than the existing system.

  相似文献   

14.
Wireless Personal Communications - One of the major factors that affects the performance of wireless sensor networks (WSN) is its limited battery capacity. Mobile wireless sensor networks (MWSN)...  相似文献   

15.
随着无线传感器网络研究和应用的发展,城市规模的无线传感器网络开始出现,然而,其大规模、低成本、移动性和节点稀疏性等特性都给定位带来了困难.基于城市移动无线传感器网络的一种典型应用,研究了不依赖全球定位系统的无线传感器网络的定位问题,在曼哈顿环概率移动模型的基础上设计定位算法,并从理论和仿真两方面分析了该算法的收敛性和稳定性.  相似文献   

16.
为克服陆地静态无线传感网和水下无线传感网因节点能耗分布不均衡而出现的能量空穴问题,和具有单一移动Sink节点的无线传感网数据收集时延过长问题,该文提出基于网格的移动无线传感网生存时间优化算法(Grid-based Lifetime Optimization Algorithm,GLOA)。GLOA算法考虑多个Sink节点的移动,将监测区域分成多个大小相同的网格。根据网格潜能值确定Sink节点移动的锚点,将锚点分配给不同的Sink节点,建立路径选择优化模型并获得Sink节点的最短移动路径,采用移动收集方法或静态收集方法循环收集数据。仿真结果表明:与Ratio_w或TPGF算法相比,GLOA算法能延长网络生存时间,降低和均衡节点能耗。与LOA_SMSN算法相比,GLOA算法能降低数据收集时延。在一定的条件下,比Ratio_w,TPGF和LOA_SMSN算法更优。  相似文献   

17.
郭江  冯斌 《微纳电子技术》2007,44(7):480-482
随着无线网络技术的日益成熟及其对小型、微型移动设备的支持,无线移动传感器网络已经逐渐成为一个研究的热点。主要讨论了为无线移动传感器网络设计的一个自适应的体系结构。在该体系结构中,使用了一个区域和核心路由节点相结合的多层结构的方法来增加无线移动网络的信息传输能力、可扩充性和可靠性,并降低网络的能耗,这样就可以适应无线移动网络的高度动态性和移动性。  相似文献   

18.
Location information is critical to mobile wireless sensor networks (WSN) applications. With the help of location information, for example, routing can be performed more efficiently. In this paper, we propose a novel localization approach, Color-theory based Dynamic Localization (CDL), which is based on color theory to exploit localization in mobile WSNs. CDL makes use of the broadcast information, such as locations and RGB values, from all anchors (a small portion of nodes with GPS receivers attached), to help the server to create a location database and assist each sensor node to compute its RGB value. Then, the RGB values of all sensor nodes are sent to the server for localization of the sensor nodes. A unique feature of our color-theory based mechanism is that it can use one color to represent the distances of a sensor node to all anchors. Since CDL is easy to implement and is a centralized approach, it is very suitable for applications that need a centralized server to collect user (sensor) data and monitor user activities, such as community health-care systems and hospital monitoring systems. Evaluation results have shown that for mobile WSNs, the location accuracy of CDL (E-CDL, an enhanced version of CDL) is 40–50% (75–80%) better than that of MCL (Hu, L., & Evans, D. (2004). Localization for mobile sensor networks. In Proceedings of the 10th annual international conference on mobile computing and networking, pp. 45–57). In addition, we have implemented and validated our E-CDL algorithm on the MICAz Mote Developer’s Kit.  相似文献   

19.
彭柳  方彦军 《通信技术》2008,41(2):108-110
文章对无线传感网络在机器人设计中的应用进行了研究,提出了一种基于Ad hoc网络的分布式无线令牌环协议的机器人通信系统实现方案,分析了其在机器人通信系统应用中的可行性.文中给出了基于无线传感网络的机器人通信系统的软硬件设计方案,并对其在移动机器人通信系统中的应用问题进行了探讨,最终提出了无线传感器网络应用于移动机器人通信系统的实现方法.  相似文献   

20.
随着无线网络技术的日益成熟及其对小型、微型移动设备的支持,无线移动传感器网络已经逐渐成为一个研究的热点。主要讨论了为无线移动传感器网络设计的一个自适应的体系结构。在该体系结构中,使用了一个区域和核心路由节点相结合的多层结构的方法来增加无线移动网络的信息传输能力、可扩充性和可靠性,并降低网络的能耗,这样就可以适应无线移动网络的高度动态性和移动性。  相似文献   

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