基于主题发布-订阅的分布式通信总线设计与实现

参考数据分发服务(Data Distribute Service,DDS)规范模型,基于组播通信和ZMQ通信库,设计并实现了一个高效、实时的主题发布订阅通信总线库(Topic Publish Subscibe Bus Library,TPSBLIB).该通信总线库采用发布-订阅工作模式,有效降低数据发送及获取节点之间的...     

发布/订阅通信模式在空间信息网络中的应用

通过对发布/订阅(P/S)通信模式和空间信息网络体系架构的分析,论证了发布/订阅(P/S)通信模式与点到点通信方式相比有一定的优势,并在此基础上,研究了基于发布/订阅通信模式的空间信息网络应用架构,设计并实现了一个基于局域网的空间信息网络发布/订阅通信模式软件模拟环境,实现了数据在网络上缓存,用户无需从数据发布者处获得资源,可直接通过网内缓存下载。     

大规模输电线路状态监测传感器网络的周期性低功耗通信技术方案

为了实现输电线路监测的功耗低、寿命长、绿色发展的目的，提出大规模输电线路状态监测传感器网络周期性低功耗通信技术方案。依据网络中传感器网络组网特征以及节点运行状态转换特点，设置睡眠定时器，以周期性运行方式使传感器网络通信节点在初始化、睡眠、激活状态间转换，通信节点在输电线路状态监测数据无传递需求时进入睡眠状态，节省通信功耗；传感器网络汇聚（sink）节点利用梯度创建上行路由，通过源路由的方式创建下行路由，以跳数和剩余能量为依据进行上、下行路由数据分组传递，降低节点功耗，延长通信运行时间。实验显示，大规模输电线路状态监测传感器网络应用该技术方案后，通信功耗明显降低，运行时间明显延长，且不会影响监测传感器网络的数据传输性能，延长了监测传感器网络的使用寿命。     

机器人系统中通信中间件的设计与实现

在分布式网络环境中,多个机器人节点间的信息交互与协同越来越多。在分析了机器人系统间的通信特点之后,提出了基于DDS的通信中间件。该中间件实现了基于主题的发布订阅,为机器人提供实时、可靠的数据传输能力。利用中间件的心跳消息,实现了机器人网络的动态重组,有效地支持了机器人节点的动态加入与退出。通过模拟实验对通信中间件的传输延迟进行了测试,实验表明该中间件能够有效地适应机器人系统应用对通信的要求。     

基于GAINZ平台的无线传感器网络设计与改进

介绍了一种无线传感器网络的改进设计方法,该方法通过在GAINZ软件平台基础上对传感器节点进行分组,并设置各个节点所能通信的网络分组,来将传感器节点划分为不同的网络组,以实现其功能。     

无线传感器网络拓扑控制策略研究

节能设计是无线传感器网络的首要设计目标,拓扑控制是实现该目标的重要技术之一,其主要目标是在保证网络连通和覆盖的前提下剔除不必要的通信链路,降低节点能耗和减少通信干扰,为MAC协议和路由协议的顺利执行提供基础。文中对传感器网络拓扑控制策略进行了的分析。最后针对目前传感器节点成本仍然很高这一特点,通过仿真得出了在节点随机配置的情况下,保证网络连通和覆盖所需的至少节点数目。并通过仿真分析证明了方案的可行性。     

无线传感器网络多汇聚节点分簇算法

为解决大规模无线传感器网络的节点通信效率问题,提出无线传感器网络的一种多汇聚节点分簇算法,针对拥有多个汇聚节点的监控区域,对网络进行层次化管理。算法通过对多种参数的综合考虑后产生簇头,并将传感器节点分配到相应的簇,由此可以有效降低节点的非均匀能耗,减少因能耗较大节点的能量过度衰竭而造成网络可用率下降。仿真结果显示,该算法可以延缓首个死亡节点的发生时间,并能有效延长无线传感器网络的整体可用率。     

大规模WSNs多层定位模型与误差分析

 针对大规模无线传感器网络的定位问题,提出了一种多层定位模型.首先根据网络中节点的不同应用与软硬件特性将节点划分为多个定位层次,并按照各层次的特性设计相应的定位算法,然后融合各定位层次为整个无线传感器网络的定位.分析研究了各层的定位误差以及层与层之间的误差传播和积累,并给出了降低这些误差的方法.仿真结果表明,分层定位模型能较好地处理误差积累问题,对节点定位误差和测距误差具有一定的容错性,在通信级节点点位误差为0.05、RSSI测距误差为0.3的情况下,相比DV-Hop算法平均点位误差减小16%.     

水声通信网络介质访问控制协议的设计与仿真

采用OPNET平台对水声通信网络节点模型与介质访问控制协议进行了设计与实现,并重点研究建立了基于忙时间改进网络分配向量帧冲突处理机制的水声通信网络协议——UMACAW。同时建立并测试了包含1个主节点与4个传感器节点的水声通信网络。仿真结果表明,MAC层采用UMACAW协议能更好地克服冲突,减少节点间端对端传输延时,从而获得更高水声通信网络的吞吐量。     

降低室内无线网络电磁辐射的能量优化算法

无论信道状态如何传统的室内无线网络节点,总是采用增加发射功率的方式以获得较好的通信效果,在一定程度上增大了室内无线网络的电磁辐射强度和网节点能耗.为此研究了室内无线网络节点的电磁辐射和能耗问题.首先给出了在确保通信效果的基础上尽可能降低网络节点发射功率的功率控制模式;然后提出了一种降低无线网络节点发射功率的能量优化算法;采用无线传感器网络的分簇技术和COST-231模型,构建了室内无线网络的路径损耗模型和最小发射功率模型,并实现了网络节点的能量优化.理论分析和仿真结果表明:该算法既保证了原有的通信效果,又降低了网络节点电磁辐射和能耗.     

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。     

Combinatorial Design of Key Distribution Mechanisms for Wireless Sensor Networks

Secure communications in wireless sensor networks operating under adversarial conditions require providing pairwise (symmetric) keys to sensor nodes. In large scale deployment scenarios, there is no priory knowledge of post deployment network configuration since nodes may be randomly scattered over a hostile territory. Thus, shared keys must be distributed before deployment to provide each node a key-chain. For large sensor networks it is infeasible to store a unique key for all other nodes in the key-chain of a sensor node. Consequently, for secure communication either two nodes have a key in common in their key-chains and they have a wireless link between them, or there is a path, called key-path, among these two nodes where each pair of neighboring nodes on this path have a key in common. Length of the key-path is the key factor for efficiency of the design. This paper presents novel deterministic and hybrid approaches based on Combinatorial Design for deciding how many and which keys to assign to each key-chain before the sensor network deployment. In particular, Balanced Incomplete Block Designs (BIBD) and Generalized Quadrangles (GQ) are mapped to obtain efficient key distribution schemes. Performance and security properties of the proposed schemes are studied both analytically and computationally. Comparison to related work shows that the combinatorial approach produces better connectivity with smaller key-chain sizes     

Group key management scheme for large-scale sensor networks

Wireless sensor networks are inherently collaborative environments in which sensor nodes self-organize and operate in groups that typically are dynamic and mission-driven. Secure communications in wireless sensor networks under this collaborative model calls for efficient group key management. However, providing key management services in wireless sensor networks is complicated by their ad-hoc nature, intermittent connectivity, large scale, and resource limitations. To address these issues, this paper proposes a new energy-efficient key management scheme for networks consisting of a large number of commodity sensor nodes that are randomly deployed. All sensor nodes in the network are anonymous and are preloaded with identical state information. The proposed scheme leverages a location-based virtual network infrastructure and is built upon a combinatorial formulation of the group key management problem. Secure and efficient group key initialization is achieved in the proposed scheme by nodes autonomously computing, without any communications, their respective initial group keys. The key server, in turn, uses a simple location-based hash function to autonomously deduce the mapping of the nodes to their group keys. The scheme enables dynamic setup and management of arbitrary secure group structures with dynamic group membership.     

Exploiting edge capability for wireless sensor networking

As considerable progress is being made in wireless sensor networking, it is envisioned that sensor nodes will be on the cubic millimeter scale, posing stringent constraints on the processing, communication, and storage capabilities of sensor nodes. While it is important to continue pursuing novel algorithms and protocols to squeeze the most out of the existing design space (sensor nodes), it is equally important to explore a new design paradigm for future sensor networks to reduce the complexity burden on sensor nodes. We propose to exploit capabilities at the network edge (i.e., an edge-based approach). We overview existing approaches to this end and present a novel edge-based routing protocol, called BeamStar, as a case study. We show that exploiting edge capability provides a new dimension of freedom for wireless sensor networking, and is effective in relieving the processing, communication, and storage requirements of sensor nodes.     

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。     

基于嵌入式的无线传感测试网络节点设计

无线传感网络不需要建设网络,可以大量快速布置,具有成本低的特点。在一些特殊的场合下,可以替代传统的有线测试网络。无线传感网络一般用于数据量较少场合,无法胜任需要较高的传输速率的场合。文中分析了影响无线传感网络使用的主要因素,通过选取混合网的网络拓扑结构,采用嵌人式微控制器LPC2129与单片收发射频芯片nRF241．01构建无线传感网络测试节点,提高了节点处理能力,同时功耗较低能够保证节点工作较长的时间,满足在一定时间内大量数据的传输要求。经过现场实测,节点设计满足设计要求。     

An efficient cluster-based communication protocol for wireless sensor networks

A wireless sensor network is a network of large numbers of sensor nodes, where each sensor node is a tiny device that is equipped with a processing, sensing subsystem and a communication subsystem. The critical issue in wireless sensor networks is how to gather sensed data in an energy-efficient way, so that the network lifetime can be extended. The design of protocols for such wireless sensor networks has to be energy-aware in order to extend the lifetime of the network because it is difficult to recharge sensor node batteries. We propose a protocol to form clusters, select cluster heads, select cluster senders and determine appropriate routings in order to reduce overall energy consumption and enhance the network lifetime. Our clustering protocol is called an Efficient Cluster-Based Communication Protocol (ECOMP) for Wireless Sensor Networks. In ECOMP, each sensor node consumes a small amount of transmitting energy in order to reach the neighbour sensor node in the bidirectional ring, and the cluster heads do not need to receive any sensed data from member nodes. The simulation results show that ECOMP significantly minimises energy consumption of sensor nodes and extends the network lifetime, compared with existing clustering protocol.     

基于信号幅度衰减测距的水下定位方法

无线传感器网络中节点规模大、能量有限、可靠性差、随机部署,无线模块的通信距离有限,虽然运用全球定位系统是个很好的选择,但是其体积大、成本高、能耗多而且需要基础设施,不适用于低成本、自组织的无线传感器网络。通过研究发现,基于信号幅度衰减测距的水下定位方法不仅能够满足无线传感器网络节点定位的要求,而且其成本较低,易理解及操作,精度高。     

小型化低功耗多媒体传感器网络节点设计

针对无线多媒体传感器网络及其性能特点,特别是在军事上的重要应用,以及当前无线多媒体传感器网络在能量、通信、计算和存储能力等方面还有待进一步完善,其节点芯片设计、三维场景的覆盖、智能多媒体信息处理和多媒体信息安全等还存在的问题,根据实验需要,设计并实现了小型化低功耗无线多媒体传感器网络节点的硬件平台,测试结果表明该设计满足指标要求。