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1.
一种新的无线传感器网络分簇模型   总被引:14,自引:3,他引:11  
从工业现场应用的角度对无线传感器网络进行研究,提出了一种新的双簇头分级模型。该模型在单簇头模型的基础上增加了一个冗余簇头节点,在簇头节点电池耗尽或出现故障之时,冗余簇头节点能够实时切换成簇头节点以维持簇稳定工作。介绍了双簇头分级模型的工作原理、覆盖范围和能耗管理,并且对该模型的性能进行了实验仿真,实验结论证明双簇头分级模型比之单簇头分级模型有更好的稳定性和安全性,以及长的生存时间而更适合应用于工业现场。  相似文献   
2.
无线传感器网络k点连通可靠性的研究   总被引:5,自引:2,他引:3  
无线传感器网络的出现引起了人们的广泛关注,由于无线传感器网络的节点不是预先定位而是随机撒放,那么如何保证一定区域内的传感器节点在满足连通可靠性要求的情况下连结成一张网络?而若干次随机抛撒所形成网络的连通度的平均值与网络的节点个数、节点的通讯半径之间又有何关系?通过计算机仿真模拟试验,给出了网络的k(k>0)连通度概率分布曲线;引入了连通度的数学期望概念来描述若干次抛撒所形成网络的连通度k的平均值,给出了其随网络节点个数、节点通讯半径变化的回归方程;给出了无线传感器网络k点连通概率曲线和3点连通的经验公式;分析了边界节点对网络连通度的影响.这些对无线传感器网络节点个数和节点通讯半径的选择、系统冗余设计等都具有重要的指导意义或参考价值.  相似文献   
3.
对传感器网络定位技术现状的研究   总被引:7,自引:0,他引:7  
杨冕  秦前清 《微机发展》2005,15(3):26-28
随着学术界对无线传感器网络研究的不断深入,传感器网络节点的定位成为当前的热点。其中主要分为两种类型算法,分别为range-free和range-based。这两种类型的定位算法各有优势和不足之处。为了研究算法发展趋势,文中通过比较几种典型的定位算法,指出了各自的优缺点。最后指出了定位算法的发展趋势:range-based的定位算法比range-free的算法更适合传感器网络小型化、低成本化的需求,应该得到更大的发展。  相似文献   
4.
嵌入式无线传感器网络节点设计   总被引:6,自引:0,他引:6  
在分析无线传感器网络的体系结构的基础上,从硬件设计、软件设计和软、硬件协同设计等几方面对无线传感器网络的节点设计进行了探讨,对链路层和网络层协议进行了研究,并从硬件和软件的角度进行了节点的节能考虑。  相似文献   
5.
无线传感器网络节点定位机制研究   总被引:1,自引:1,他引:0  
传感器网络中的节点定位问题与很多实际应用直接相关,主要有两类算法,即 rang-free和rang-based,这两类定位算法各有其优势和不足.为了研究算法的发展趋势,比较了几种典型的定位算法,指出了各自的优缺点.  相似文献   
6.
用无线传感器网络探测跟踪目标   总被引:1,自引:0,他引:1  
与传统的探测跟踪方法相比,无线传感器网络以其良好的特性弥补了传统跟踪方法的不足。文章介绍了无线传感器网络的体系结构,探讨了无线传感器网络探测跟踪目标的策略和方法,最后提出了用无线传感器网络跟踪目标需要考虑的问题。  相似文献   
7.
无线传感网络(WSN)研究   总被引:14,自引:0,他引:14  
随着智能化、网络化传感器技术的日益成熟,具有潜在的巨大应用价值的无线传感网络引起人们的重视与研究.文章介绍了无线传感网络的特点和结构形式,并对传感网络目前的研究动态、研究方向以及挑战作了重点介绍,同时对其广泛的应用前景做了描述.  相似文献   
8.
A wireless sensor network (WSN) consists of a large number of small devices with computational power, wireless communication and sensing capability. These networks have been developed for a wide range of applications, such as habitat monitoring, object tracking, precision agriculture, building monitoring and military systems. Meanwhile, middleware systems have also been proposed in to facilitate both the development of these applications and provide common application services. The development of middleware for sensor networks, however, places new challenges on middleware developers due to the low availability of resources and processing capacity of the sensor nodes. In this context, this paper presents the design and implementation of a middleware for WSN named Mires. Mires incorporates characteristics of message-oriented middleware by allowing applications communicate in a publish/subscribe way. In order to illustrate the proposed middleware, we have also developed an environment-monitoring application and a data aggregation service.
Judith KelnerEmail:
  相似文献   
9.
On Connected Multiple Point Coverage in Wireless Sensor Networks   总被引:4,自引:0,他引:4  
We consider a wireless sensor network consisting of a set of sensors deployed randomly. A point in the monitored area is covered if it is within the sensing range of a sensor. In some applications, when the network is sufficiently dense, area coverage can be approximated by guaranteeing point coverage. In this case, all the points of wireless devices could be used to represent the whole area, and the working sensors are supposed to cover all the sensors. Many applications related to security and reliability require guaranteed k-coverage of the area at all times. In this paper, we formalize the k-(Connected) Coverage Set (k-CCS/k-CS) problems, develop a linear programming algorithm, and design two non-global solutions for them. Some theoretical analysis is also provided followed by simulation results.  相似文献   
10.
We introduce a novel sensor node management and location estimation method referred as sectoral sweeper (SS) scheme that uses an adaptive antenna array (AAA) at a central node in wireless sensor networks (WSNs). With the SS scheme, the central node can activate or deactivate the nodes in a desired region which is specified by beam direction and beam width of the transmit beam and also by minimum and maximum thresholds (R min and R max) for the received signal strength indicator (RSSI) of signals received by the nodes. In order to perform a specified task that is associated with a Task_id, two different beams are transmitted, which are task region beam and routing region beam to switch the nodes into active or routing modes. Since our scheme does not require any additional software or hardware for node management and location estimation in sensor nodes, the deficiencies of tiny sensors are effectively eliminated. The proposed scheme is shown to reduce the number of sensing nodes and the amount of data traffic in the network, thus leading to considerable savings in energy consumption and prolonged sensor lifetime. Ayhan Erdogan graduated from Turkish Naval Academy, Istanbul, in 1992. He received the MSdegree from the Computer Engineering, Naval Sciences and Engineering Institute, Turkish Naval Academy, Istanbul, in 2003. He attended to a one year training on Automatic Data Processing (ADP) Officer in Middle East Technical University, Turkey, in 1996. He worked as a Project Officer for Turkish Armed Forces Integrated Communication Systems Project developed by Turkish General Stuff, from 1996 until 2001. He is currently a PhD student at the Electronics Engineering and Computer Science Department, Sabanci University, Istanbul, Turkey. His current research interests include Wireless Sensor Networks and Security for Ad hoc Networks. Vedat Coskun was born in Istanbul, Turkey, in 1962. He was graduated from Turkish Naval Academy, Istanbul, Turkey, in 1984. He received the M.Sc. degree from the Computer Science Department, Naval Post Graduate School, CA, USA, in 1990 and the Ph.D. degree from the Computer Engineering Department, Yildiz Technical University, Istanbul, in 1998. He managed the wargaming software development group in Turkish Naval Military Wargaming Center for 5 years. Hewas teaching assistant, faculty member and chairman with the Computer Engineering Department, Turkish Naval Academy. He was part-time visiting professor with Gebze Institute of Technology. He is currently an Assistant Professor with the Department of Information Technology, ISIK University, Istanbul, Turkey. His current research interests include algorithm design, wireless sensor and actuator networks, and cryptography Adnan Kavak was born in Usak, Turkey, in 1970. He received the B.S. degree from the Electrical and Electronics Engineering Department, Middle East Technical University, Ankara, Turkey, in 1992. He received the MS and PhD. degrees from the Electrical and Computer Engineering Department, The University of Texas at Austin, TX, USA, in 1996 and 2000, respectively. He was a satellite control engineer with Turksat Satellite Control Center, Ankara, Turkey, from December 1992 to May 1994. He worked as a Senior Research Engineer at Wireless Systems Laboratory, Samsung Telecommunications America in Richardson, TX, USA, from January 2000 to July 2001. He then joined Kocaeli University, Turkey, in August 2001 and worked as an Assistant Professor there until May 2005. Currently, he is the director ofWireless Communications and Information Systems (WINS) Research Center, and an Associate Professor with the Computer Engineering Department, Kocaeli University, Turkey. His current research interests include 3G and next generation wireless networks, software radios, smart antenna systems, resource allocation in 3G networks, and wireless sensor networks.  相似文献   
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