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Neighbor discovery enables nodes in the networks to discover each other through simple information interaction,which was suitable for the new mobile low duty cycle sensor network (MLDC-WSN).However,because the nodes in MLDC-WSN can move randomly and sleep,the network topology was changed frequently,which results in that some nodes need a lot of energy and time to find their neighbors.How to realize fast neighbor discovery for all nodes in the network was a difficult problem in current research.To solve this problem,a new low-latency neighbor discovery algorithm based on multi-beacon messages was proposed.In this algorithm,the nodes were discovered by sending a short beacon message through their neighbor nodes,and by adjusting the time and frequency of beacon message sent,a lower neighbor discovery delay was obtained.Eventually,through quantitative analysis and simulation experiments,it is found that compared with existing algorithms,this algorithm can find all neighbor nodes in MLDC-WSN with less energy consumption,lower latency and greater probability. 相似文献
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Mobile low-duty-cycle wireless sensor network is a new kind of wireless multi-hop network,which is self-organized by a large number of nodes that have mobile ability and are able to get into sleep for a long time.Such networks have wide application prospects in national defense,industry,agriculture and other fields that need long term monitoring in severe environments.However,the movement and the sleeping features of nodes lead to constantly change of network topology,which makes the nodes difficult to discover their neighbors quickly.Therefore,the nodes cannot achieve optimal distribution decisions.In order to solve this problem,a new proactive neighbor discovery algorithm was proposed.This algorithm made the nodes in the network take the initiative to find their neighbors when they woke up,and avoided the delay caused by long time waiting in the traditional passive neighbor discovery.In addition,by predicting the movement speed and distance of neighbors,the neighbor set at the next moment can be quickly determined,which can further reduce the delay and obtain more accurate neighbor discovery results.Theoretical analysis and experimental results show that compared with the existing algorithms,the algorithm can find all the neighbors in MLDC-WSN with less energy consumption and lower delay. 相似文献
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无线传感器网络(WSN)是一种多跳自组织网络,它由大量具有有限能力的节点组成,在工业、农业、交通、国防等领域具有广泛应用.为了减少节点的能量消耗,延长网络的生命周期,近年来逐渐出现了基于低占空比技术(Low-Duty-Cycle)的WSN,简称LDC-WSN.在LDC-WSN中,节点在一个工作周期内大部分时间处于睡眠状态,只有极少时间内处于工作状态.MAC协议是实现LDC-WSN中节点睡眠调度的关键,对LDC-WSN保持正常工作并获得理想的工作性能具有非常重要的意义.针对LDC-WSN中MAC协议的研究仍处于起步阶段,是目前研究的热点.对当前研究进行综述,详细介绍和分析LDC-WSN中最具代表性和较新的MAC协议.通过对比和总结当前工作的优缺点,明确了目前存在的问题和难点,为未来更深入的研究指明了方向. 相似文献
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This paper considers a spatially separated wireless sensor network, which consists of a number of isolated subnetworks that could be far away from each other in distance. We address the issue of using mobile mules to collect data from these sensor nodes. In such an environment, both data‐collection latency and network lifetime are critical issues. We model this problem as a bi‐objective problem, called energy‐constrained mule traveling salesman problem (EM‐TSP), which aims at minimizing the traversal paths of mobile mules such that at least one node in each subnetwork is visited by a mule and the maximum energy consumption among all sensor nodes does not exceed a pre‐defined threshold. Interestingly, the traversal problem turns out to be a generalization of the classical traveling salesman problem (TSP), an NP‐complete problem. With some geometrical properties of the network, we propose some efficient heuristics for EM‐TSP. We then extend our heuristics to multiple mobile mules. Extensive simulation results have been conducted, which show that our proposed solutions usually give much better solutions than most TSP‐like approximations. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Mohammad Towhidul Islam Mursalin Akon Atef Abdrabou Xuemin Shen 《Wireless Communications and Mobile Computing》2014,14(7):745-760
Data/content dissemination among the mobile devices is the fundamental building block for all the applications in wireless mobile collaborative computing, known as mobile peer‐to‐peer. Different parameters such as node density, scheduling among neighboring nodes, mobility pattern, and node speed have a tremendous impact on data diffusion in a mobile peer‐to‐peer environment. In this paper, we develop analytical models for object diffusion time/delay in a wireless mobile network to apprehend the complex interrelationship among these different parameters. In the analysis, we calculate the probabilities of transmitting a single object from one node to multiple nodes using the epidemic model of spread of disease. We also incorporate the impact of node mobility, radio range, and node density in the networks into the analysis. Utilizing these transition probabilities, we estimate the expected delay for diffusing an object to the entire network both for single object and multiple object scenarios. We then calculate the transmission probabilities of multiple objects among the nodes in the wireless mobile network considering network dynamics. Through extensive simulations, we demonstrate that the proposed scheme is efficient for data diffusion in the wireless mobile network. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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为了解决当前移动无线传感网数据传输中存在的同步寻址困难以及节点间功率交互难以均衡化的问题,提出了一种新的移动无线传感网数据传输算法。首先,采取广播机制实现同步控制分组传输,降低同步流量对寻址过程造成的压力;随后使用区域节点流量阀控制机制,且通过侦听方式记录并获取sink节点—区域节点链路间的数据流量,进一步采取流量—链路均衡方式促进流量均衡化;最后,通过基于轮数—sink 链路周期抖动筛选方式确认受限带宽,减少带宽受限导致的传输故障。仿真实验表明,与BLT-NB2R算法、NLSC算法和HT2C算法相比,所提出的算法可改善数据传输带宽,降低数据分组丢失频率,能够较好地满足实践需求。 相似文献
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提出传感器网络环境下基于DTW的多小波数据压缩算法。首先研究汇聚节点中异步数据点—点对的对应关系,设计迭代算法求出具有最大相关性的DTW弯曲路径。接着提出最佳匹配点选择算法,通过DTW弯曲路径中一对一数据点—点对来预测异步数据向量间的函数关系,获取最佳匹配点,得到具有最大相关性的传感数据矩阵。然后设计多小波变换,利用传感数据矩阵的相关性来压缩数据,同时解决数据矩阵的行列不对称问题。实验结果表明,所提出的算法在能量聚集比、重构精度和运行时间等压缩性能指标上优于经典的分布式小波压缩算法。 相似文献
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基于数据融合的无线传感器网络路由算法 总被引:2,自引:0,他引:2
在分簇协议LEACH和链状协议PEGASIS的基础上,提出一种新的基于数据融合的分簇路由算法.簇首节点采用多跳方式传输数据,并根据周围节点的密集程度构造不同大小的簇;簇内节点计算上行和下行节点构造数据融合树,采用时分复用调度算法进行多跳路由.NS2仿真结果表明该路由算法均衡了各个节点的能量消耗,延长了网络存活时间,并降低了网络延迟. 相似文献
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视频传感器网络VSN(Video Sensor Network)相对于传统的传感器网络需要更高的带宽和更低的延时。文中提出了一种适合于VSN的多径路由算法MPTT(Multi-path Predicted Transmission Time)。这种路由算法是从MAC层建模,根据链路邻居节点的流量信息来估算出路径的整体延时,再根据每条路径延时的大小分配数据流量使其总体的延时达到最小。经过仿真可以得出,在数据流量不大时,该算法与延时最小的路径延时相当。随着所分配流量的加大,MPTT比DSR延时要小,而且可以提供更高的数据流带宽。 相似文献
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基于无线传感网络及移动主体的远程医疗监护系统研究 总被引:1,自引:0,他引:1
电子健康保健是一项高度分布、特别费力、具有移动性的工作,经常要对各种类型的医疗设备进行信息存取,给异构系统间的信息交换带来了困难。提出了一种基于无线传感网络与移动Agent的远程医疗监护系统,以适应健康保健环境高度分布的特点。给出了系统体系结构模型,采用Aglets软件开发包进行了原型设计,通过监控平台与便携的无线生命体征监控传感节点相结合,对病人的健康状态进行长期在线监控,实现医疗资源的优化利用。 相似文献
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目前多数移动自组织路由协议选择路径都是基于跳数最短的单径路由.从能量角度看,多数路由协议并没有充分利用网络资源.文章提出一种多径节能路由(Muhipath Saving Dynamic Source Routing,MSDR)协议.实验结果表明,该协议不仅提高了网络可靠性,而且还有效地延长了节点的工作时间和网络的整体寿命. 相似文献
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在深入了解移动网络中蒙特卡洛(MCL)算法的基础上,针对MCL算法在锚节点率较少时定位精度较差的缺点提出了一种结合MCL算法与分布式MDS-MAP(Distribute MDS-MAP,DMDS-MAP)算法的自适应算法MCL-MDS定位算法。算法首先使用所设计的DMDS-MAP算法对节点进行定位,随后利用MCL算法中的过滤原理对定位结果进行验证,若通过验证,则采用该定位结果,否则采用MCL算法的定位结果。仿真显示,MCL-MDS定位算法能在各种环境下获得较好的定位效果。 相似文献
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考虑移动传感器的移动会大量消耗能量且比较昂贵,使用密度为O(k)的移动传感器来满足网络k-覆盖的密度需求,并给出了网络要达到k-覆盖传感器需移动的最大距离的一个界O((log L)1/3);建立了三维网络传感器移动数学模型,将传感器重新部署问题转化为最大网络流问题,用分布式重新部署算法仿真证明了其有效性。 相似文献
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Zusheng Zhang Liang Chen Zhiqi Wang Fengqi Yu 《International Journal of Communication Systems》2013,26(8):1074-1088
Query processing systems in wireless sensor networks usually support tasks such as data acquisition, data aggregation, and event‐based query. The performances of query processing with these tasks are greatly varied according to different routing protocols. Most existing data query systems usually use one routing protocol to deal with all kinds of queries. This work demonstrates that proper selection of routing protocols can improve the performance of query processing. We propose a dynamic routing layer that makes protocol selection on the basis of query tasks and can automatically switch between different routing protocols. Simulation results show that dynamic routing scheme is more energy efficient than single routing protocol. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Zhihong Liu Jianfeng Ma Youngho Park Shangrong Xiang 《Wireless Communications and Mobile Computing》2012,12(13):1131-1146
Unattended wireless sensor networks operating in hostile environments face the risk of compromise. Given the unattended nature, sensors must safeguard their sensed data of high value temporarily. However, saving data inside a network creates security problems due to the lack of tamper‐resistance of sensors and the unattended nature of the network. In some occasions, a network controller may periodically dispatch mobile sinks to collect data. If a mobile sink is given too many privileges, it will become very attractive for attack. Thus, the privilege of mobile sinks should be restricted. Additionally, secret keys should be used to achieve data confidentiality, integrity, and authentication between communicating parties. To address these security issues, we present mAKPS, an asymmetric key predistribution scheme with mobile sinks, to facilitate the key distribution and privilege restriction of mobile sinks, and schemes for sensors to protect their collected data in unattended wireless sensor networks. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献