无线传感器网络中一种基于OSTBC的高效协作传输技术

针对发端能量受限的无线传感器网络提出了一种基于OSTBC的高效虚拟MIMO协作传输策略.在无线传感器网络的每个簇内采用一种全速率的分布式OSTBC传输方案,同时对调制方式的星座大小进行优化,创建了一种更高效的无线传感器网络和MIMO通信相结合的模型.针对该模型在接收端进行迭代译码,并推导出该系统的总能耗函数和网络时延算式.通过仿真显示,该模型不仅能够极大的降低发端能耗,对任意协作节点数目均能够实现全速率传输,解决了传统分布式空时码用于无线传感器网络时发端的数据积压问题,减小了网络时延.因此本协作传输模型从能量消耗和网络时延两方面对无线传感网的性能进行了提升,能够为无线传感网的应用提供有意义的参考.     

基于ARM7的无线传感器网络节点能量管理初探

为了研究无线传感器网络能量管理和组网技术,采用ARM基高性能、低功耗微控制器LPC2138为核心制作了一种新型无线传感器网络节点,该节点由两节AA电池供电.说明了该节点的硬件构成及设计方法,介绍了该无线传感器网络节点使用的电池模型,并给出了一组该节点有效工作状态下的功率.     

一种非对称耦合无线传感器网络同步控制模型

无线传感器网络作为一种复杂网络,具有节点众多、拓扑时变等特点。研究传感器网络中的同步问题对于利用节点众多这一特点,实现MIMO协作信息传输、混沌保密通信等应用有着重要的意义。现有对于网络同步的研究大都集中于研究规则网络模型。然而对于无线传感器网络来说,由于无线信道的固有时变特性以及无线传感器网络节点易失效等原因造成了网络拓扑动态变化,从而给传感器网络同步问题的数学建模和分析造成了很大的困难。本文工作受到Belkh[1]工作的启发,提出一种非对称耦合传感器网络同步控制模型。该模型避开了讨论研究具体的网络拓扑结构下的网络同步问题,代之以从控制的角度研究如何改善网络同步性能。理论分析和实验结果表明该模型能够显著提高网络同步化性能。      

基于ARM7的无线传感器网络节点能量管理初探

为了研究无线传感器网络能量管理和组网技术,采用ARM基高性能、低功耗微控制器LPC2138为核心制作了一种新型无线传感器网络节点,该节点由两节AA电池供电。说明了该节点的硬件构成及设计方法,介绍了该无线传感器网络节点使用的电池模型,并给出了一组该节点有效工作状态下的功率。     

基于ARM7的无线传感器网络节点能量管理初探

为了研究无线传感器网络能量管理和组网技术，采用ARM基高性能、低功耗微控制器LPC2138为核心制作了一种新型无线传感器网络节点，该节点由两节AA电池供电。说明了该节点的硬件构成及设计方法，介绍了该无线传感器网络节点使用的电池模型，并给出了一组该节点有效工作状态下的功率。     

信号强度和运动向量结合的无线传感器网络移动节点定位

无线传感器网络的定位是近年来无线传感器网络研究的重要课题.本文首先介绍了无线传感器网络的来源、重要性以及无线传感器网络定位的分类.然后提出了一种全新定位算法,信号强度和运动向量结合的无线传感器网络移动节点定位,简称SSMV算法,在外围布置四个锚节点,得用信号强度和未知节点在运动中向量的变化,对锚节点在内的未知节点进行定位,并对该算法进行了仿真和总结.通过与凸规划法进行比较,仿真结果表明,该算法有更高的定位精度.     

WSN中同构模型下动态组密钥管理方案

研究了同构网络模型的组密钥管理问题,首次给出了一个明确的、更完整的动态组密钥管理模型,并提出了一种基于多个对称多项式的动态组密钥管理方案。该方案能够为任意多于2个且不大于节点总数的节点组成的动态多播组提供密钥管理功能,解决了多播组建立、节点加入、退出等所引发的与组密钥相关的问题。该方案支持节点移动,具有可扩展性,并很好地解决了密钥更新过程中多播通信的不可靠性。组成员节点通过计算获得组密钥,只需要少量的无线通信开销,大大降低了协商组密钥的代价。分析比较认为,方案在存储、计算和通信开销方面具有很好的性能,更适用于资源受限的无线传感器网络。     

基于ATmega128的无线传感器网络节点设计

传感器节点是无线传感器网络的基本组成单位。大量无线传感器网络节点通过自组织方式构成网络,利用网络节点中各种传感器,能够实时采集和处理节点覆盖区域内的各种参数。介绍了无线传感器网络节点结构、节点组成单元的硬件电路和节点的软件结构。该节点以ATmega128低功耗处理器为核心,结合传感器电路和CC2420射频收发模块,实现对观察区域的实时监测。     

基于捕获效应的传感器网络MAC层研究

基于Markov链理论提出了一种新的理论模型用于描述无线传感器网络MAC层回退机制,该模型重点考虑了密集分布的无线传感器节点中普遍存在的捕获效应,并给出了新模型下节点发送概率的解析解。在此基础上,进而提出了一种新的无线传感器网络吞吐率计算模型,通过仿真分析,基于该模型计算所得到的网络吞吐率理论值要大于没有考虑捕获效应的网络吞吐率理论值。因此提出的新模型能够更准确地描述捕获效应对无线传感器网络的影响。     

基于TinyOS-2.x的无线传感器网络数据包传输机制的研究

为深入解析无线传感器网络中上位机接收到的数据包,在目前最新的无线传感器网络嵌入式操作系统TinyOS-2.x平台基础上设计了一套实验,成功读取了MAC层的数据包.发现传感器节点采集到的数据首先作为MAC层的有效荷载封包无线传送到基站节点,由基站节点将其作为串口消息包的有效荷载再次封包异步传送到传感器网络的上位机端.该研究对进一步理解TinyOS的构架、运行机制和通讯机制,开发相关的应用软件具有一定参考意义.     

基于簇结构的无线传感器网络路由研究综述

介绍了典型分簇无线传感器网络路由协议的分类,总结了分簇路由协议的研究进展。针对无线传感器网络从同构型网络向异构型网络发展的趋势和特点,指出了路由协议向节点间相互协作的发展方向,并且在设计路由协作算法时可采用与无线传感器网络极为相似的多Agent系统模型。     

无线传感器网络的神经网络模型

无线传感器网络是复杂的无线网络。无线传感器网络拥有大量的网络节点。网络节点是无线传感器网络的基础。为了研究复杂的无线传感器网络，采用了神经元描述了WSN的网络节点，用神经元模型表示了无线传感器网络。给出了无线待感器网络节点的神经元模型和无线传感器网络的神经网络模型，并将神经网络应用于无线传感器网络的数据融合应用。结果表明，基于神经网络的无线传感器网络研究可以使得复杂研究变得简单，利于开展WSN的深入研究。     

Communication Coverage in Wireless Passive Sensor Networks

System lifetime of wireless sensor networks (WSN) is inversely proportional to the energy consumed by critically energy-constrained sensor nodes during RF transmission. In that regard, modulated backscattering (MB) is a promising design choice, in which sensor nodes send their data just by switching their antenna impedance and reflecting the incident signal coming from an RF source. Hence, wireless passive sensor networks (WPSN) designed to operate using MB do not have the lifetime constraints of conventional WSN. However, the communication performance of WPSN is directly related to the RF coverage provided over the field the passive sensor nodes are deployed. In this letter, RF communication coverage in WPSN is analytically investigated. The required number of RF sources to obtain interference-free communication connectivity with the WPSN nodes is determined and analyzed in terms of output power and the transmission frequency of RF sources, network size, RF source and WPSN node characteristics.     

小型无线传感器网络的实现与P2P互联

传感器网络之间的互联与通信将成为未来无线传感器网络的应用模式之一,通过P2P技术互联多小传感器网络,奇为用户提供大规模、大范围、多样化的信息服务。在设计和实现基于SimplciTl协议的小型无线传感器网络的基础上,提出在无线传感器网络上的P2P覆盖,利用JXTA协议搭建P2P平台,实现了多个传感器网络以P2P的方式互联,并给出了硬件和软件的实现方案。     

Smartphone with Augmented Gateway Functionality as Opportunistic WSN Gateway Device

Sensors and actuators are being increasingly deployed for monitoring and controlling different phenomena and processes in a stand-alone manner or attached to sensor nodes with communication capabilities as part of larger wireless sensor networks (WSN). In addition to the protocols for communication within the WSN, sensor nodes may also provide the gateway functionality towards other networks and/or support communication with other external devices. These devices either represent additional gateways for exposing data and metadata to external networks, or serve as connection points to WSN for instance for the on-site calibration and maintenance. Smartphones as advanced mobile terminals appear particularly suitable for such role. This paper investigates the role a smartphone augmented with WSN gateway functionality can play in WSN with respect to regular dedicated sensor and gateway nodes. As a practical example we show the implementation of a gateway augmented smartphone using a Samsung i8910 phone and a VESNA sensor node connected via Bluetooth. The role of a gateway augmented smartphone is to interface between WSN, which is using a proprietary networking protocol, and the mobile network. The data obtained from WSN can be enriched using smartphone’s embedded sensors before being sent to the remote server. We demonstrate this on an example of geo-tagging the collected data from WSN with the smartphone’s Global Positioning System-based location data.     

QoS evaluation of energy-efficient ML-MAC protocol for wireless sensor networks

Power management is an important issue in wireless sensor networks (WSNs) because wireless sensor nodes are usually battery powered, and an efficient use of the available battery power becomes an important concern specially for those applications where the system is expected to operate for long durations. This necessity for energy efficient operation of a WSN has prompted the development of new protocols in all layers of the communication stack. If the radio transceiver is the most power consuming component of a typical sensor node, large gains can be achieved at the link layer where the medium access control (MAC) protocol controls the usage of the radio transceiver unit.     

Towards a classification of energy aware MAC protocols for wireless sensor networks

Power management is an important issue in wireless sensor networks (WSNs) because wireless sensor nodes are usually battery powered, and an efficient use of the available battery power becomes an important concern specially for those applications where the system is expected to operate for long durations. This necessity for energy efficient operation of a WSN has prompted the development of new protocols in all layers of the communication stack. Provided that, the radio transceiver is the most power consuming component of a typical sensor node, large gains can be achieved at the link layer where the medium access control (MAC) protocol controls the usage of the radio transceiver unit. MAC protocols for sensor networks differ greatly from typical wireless networks access protocols in many issues. MAC protocols for sensor networks must have built‐in power conservation, mobility management, and failure recovery strategies. Furthermore, sensor MAC protocols should make performance trade‐off between latency and throughput for a reduction in energy consumption to maximize the lifetime of the network. This is in general achieved through duty cycling the radio transceiver. Many MAC protocols with different objectives were proposed for wireless sensor networks in the literature. Most of these protocols take into account the energy efficiency as a main objective. There is much more innovative work should be done at the MAC layer to address the hard unsolved problems. In this paper, we first outline and discuss the specific requirements and design trade‐offs of a typical wireless sensor MAC protocol by describing the properties of WSN that affect the design of MAC layer protocols. Then, a typical collection of wireless sensor MAC protocols presented in the literature are surveyed, classified, and described emphasizing their advantages and disadvantages whenever possible. Finally, we present research directions and identify open issues for future medium access research. Copyright © 2009 John Wiley & Sons, Ltd.     

基于移动中继站的无线传感器网络设计

WSN（无线传感器网络）是由大量分布式的不同规格和功能的具有感知、计算和通信能力的微型传感器节点通过自组织的方式构成的一个小范围的无线网络。为了解决无线传感器的远距离通信中继问题,能够将网络信息通过中继顺利地传送到远程终端,设计了基于移动螃蟹的传感器网络。它以机器螃蟹作为中继,进行数据的本地化处理和融合,实现分布式数据采集和监控。本系统应用于大规模的无线网络,增加了设备状态数据采集与通信的距离,有效地增强了系统的健壮性。     

Coverage based inter cluster communication for load balancing in heterogeneous wireless sensor networks

Effective energy management in heterogeneous wireless sensor networks is more challenging issue compared to homogeneous wireless sensor networks. Much of the existing research focuses on homogeneous wireless sensor networks. The energy conservation schemes for the homogeneous wireless sensor networks do not perform efficiently when applied to heterogeneous wireless sensor networks. The proposed algorithm in this paper exploits the redundancy properties of the wireless sensor networks and also changes the inter cluster communication pattern depending on the energy condition of the high energy nodes during the life cycle of the heterogeneous wireless sensor networks. Performance studies indicate that the proposed algorithm effectively solves the problem of load balancing across the network and is more energy efficient compared to multi hop versions of the standard low energy adaptive clustering hierarchy protocol.     

Wireless sensor networks based on modular arithmetic

The authors propose the method for data coding in wireless sensor networks (WSN) based on the transformation of the residue number system and multipath routing. It enables to utilize efficiently the bandwidth of communication channels as well as reduce message delivery time. It is explored the ant algorithm to search an optimal route of data transmission in the wireless sensor network. There is introduced a limitation for the communication radius of the wireless unit that shorts a number of the search decision modes and improves the accuracy of the wireless network simulation. The correspondent software is designed, it allowes exploring the dynamics of finding the optimal transmission path in WSN in case of different algorithm settings, and exploring the impact of the elite ants on the accuracy of the found path.