普适计算环境下无线传感器网络研究

主要对在普适计算(ubiquitous computing or pervasive computing)环境下的无线传感器网络进行了研究。首先,介绍普适计算和无线传感器网络概念;其次,论述在普适计算环境下,无线传感器网络各项技术的研究,包括:面向普适计算的无线传感器网络中间件研究,无线传感器网络与物联网的融合研究和普适环境下无线传感器网络的各项关键性技术研究,如传感器的功耗问题和节点供电问题。最后:无线传感器网络的一些优点能方便人们更好地实现普适计算中的通信、感知、场景识别等功能,在未来,它将会是实现普适计算的主要途径。     

Coverage aware face topology structure for wireless sensor network applications

Wireless Networks - Providing effective sensing coverage of an observation area with reduced set of working nodes for maximum duration of time is an important concern for the development of durable...     

Automated network selection in a heterogeneous wireless network environment

Service delivery in a heterogeneous all-IP wireless network environment requires the selection of an optimal access network. Selection of a non-optimal network can result in undesirable effects such as higher costs or poor service experience. Network selection in such an environment is influenced by several factors, and currently a complete solution is not available to solve this problem. This article describes a comprehensive decision making process to rank candidate networks for service delivery to the terminal. The proposed mechanism is based on a unique decision process that uses compensatory and non-compensatory multi-attribute decision making algorithms jointly to assist the terminal in selecting the top candidate network     

低功耗无线传感器网络

全球对＂绿色＂科技和能源使用效率的需求推动着新一代超低功耗无线网络的发展。这种新一代网络正在不断发展以用于工业和控制应用中基于传感器的远程系统;此外,它也促使更多应用更好地使用无须任何网络电缆或电源线的真正无线解决方案。     

Routing in mobile wireless sensor network: a survey

The Mobile Wireless Sensor Network (MWSN) is an emerging technology with significant applications. The MWSN allows the sensor nodes to move freely and they are able to communicate with each other without the need for a fixed infrastructure. These networks are capable of out-performing static wireless sensor networks as they tend to increase the network lifetime, reduce the power consumption, provide more channel capacity and perform better targeting. Usually routing process in a mobile network is very complex and it becomes even more complicated in MWSN as the sensor nodes are low power, cost effective mobile devices with minimum resources. Recent research works have led to the design of many efficient routing protocols for MWSN but still there are many unresolved problems like retaining the network connectivity, reducing the energy cost, maintaining adequate sensing coverage etc. This paper addresses the various issues in routing and presents the state of the art routing protocols in MWSN. The routing protocols are categorized based on their network structure, state of information, energy efficiency and mobility. The classification presented here summarizes the main features of many published proposals in the literature for efficient routing in MWSN and also gives an insight into the enhancements that can be done to improve the existing routing protocols.     

基于无线传感网的粮库环境监测系统设计

针对粮库环境监测问题,提出了一种基于无线传感网技术的粮库环境监测系统,阐述了系统设计原理和软硬件实现方法。该系统通过传感器节点采集粮库环境数据,并将数据发送至汇聚节点。汇聚节点接收多个传感器节点的数据,通过有线通讯方式将数据传送至后方监控平台处理。该系统具有精度高、灵活性强和功耗低等优点。     

软交换在无线通信网中的应用

在无线通信中，通过分组交换实现语音传输与传统的通过PSTN在技术上有很大的不同。在VoIP中，语音信号以数据报的形式在专用或公用IP网上传输，而不是通过电路交换在PSTN网中传输。在传统的蜂窝网中，语音信号是通过移动交换中心（MSC）进行电路交换。软交换在3G中的应用本文重点分析软交换在UMTS标准中的应用。UMTS标准现有三个版本，分别是R99、R4和R5。简言之，在R99中，无线核心网是基于ATM的，因此MSC必须升级以满足ATM接入。在R4中，MSC被分解为软交换设备（MSCServers）和媒体网关（MediaGateway），前者实现MS…     

一种基于无线透传传感网络的分布式环境监测系统的设计

设计了一种基于无线透传传感网络的分布式环境监测系统。设计采用1100E射频芯片作为无线收发芯片,通过在ATmega128L微处理器中编写透传算法程序,实现对各环境参数的数据透传,使用RS 232C串口与PC机进行通信,实现了对目标监测区域各环境参数的实时采集。给出实验测试采集到的多组数据,通过对实验数据的分析,说明该设计可以在400 m内同时实现对254个无线节点的实时监测,测量误差约为±0.1%~±3%。     

应用于2.4GHz无线传感网的超低功耗射频接收前端设计

This paper presents the design of an ultralow power receiver front-end designed for a wireless sensor network （WSN） in a 0.18 μm CMOS process. The author designs two front-ends working in the saturation region and the subthreshold region respectively. The front-ends contain a two-stage cross-coupling cascaded common-gate （CG） LNA and a quadrature Gilbert IQ mixer. The measured conversion gain is variable with high gain at 24 dB and low gain at 7 dB for the saturation one, and high gain at 22 dB and low gain at 5 dB for the subthreshold one. The noise figure （NF） at high gain mode is 5.1 dB and 6.3 dB for each. The input 1 dB compression point （IPldB） at low gain mode is about -6 dBm and -3 dBm for each. The front-ends consume about 2.1 mA current from 1.8 V power supply for the saturation one and 1.3 mA current for the subthreshold one. The measured results show that, comparing with the power consumption saving, it is worth making sacrifices on the performance for using the subthreshold technology.     

一种无线传感网络节能MAC协议

在无线传感网络中,传感节点是能量受限的,因此能耗在这种网络显得十分重要,关系到整个网络的生命周期与性能.而无线传感网络的MAC协议对节点的节能有着重要的作用.本文在已有研究的基础上加以改进形成一种更有效的感知流量信息进行节能的MAC协议.该协议同S-MAC协议一样也是采用睡眠的机制,但不同于S-MAC的是该协议中监听与...     

Routing with hexagonal virtual coordinates in wireless sensor networks

Using geographic routing, like GPSR, is efficient for ad hoc and wireless sensor networks, but it requires that nodes be aware of their physical positions. However, if there are holes in the network, routing across them using GPSR will lead to a lot of overloaded nodes on their boundaries. In this paper, we propose a distributed protocol, named hexagonal virtual coordinate (HVC), for constructing a virtual coordinate system. After the HVC is constructed, the nodes in the network will be aware of the relative coordinates among the landmarks through the HVC chart. Based on the HVC chart, a source node can find an auxiliary routing path (ARP) to indicate the direction of the journey from the source to the destination. Simulation results show that our protocol can support geographic routing efficiently, and the landmarks found by our protocol are uniformly located in the network even if some holes exist within it. In addition, our protocol is resilient to various network shapes and can find a load balancing routing path to the destination even if this path comes across holes in the network. Copyright © 2008 John Wiley & Sons, Ltd.     

Reliable data approximation in wireless sensor network

Wireless Sensor Network (WSN) is highly budgeted by energy since sensor nodes are mostly battery-powered and deployed in hard-to-reach area for prolonged duration. Moreover radio communication is very expensive for WSN. At the same time, a substantial portion WSN applications require periodic data collection. In this paper we investigate this issue in depth and present a solution architecture: 2PDA, that eliminates repeated transmission. The solution is founded upon temporal linear correlation among sensor data. Instead of sending each data packet we model them using method of least square that exploits temporal correlation among sensor data. 2PDA observes sensor data and performs operation parameterized by application-precision. After successful computation only the parameters of the model are sent over the radio to the application-end or sink. 2PDA was implemented in TinyOS. Implementation showed a significant improvement (i.e. 80%) for the node’s life-time. Rigorous numerical analysis was done on various sensor data which indicated its modest efficiency under different scenario. Effects of various parameters such as type of sensory information, time and place of data collection were assessed. Finally a network simulation was carried out to evaluate its scalability.     

无线传感网用振动加速度传感器几点探索

无线传感网是由具有无线通信、数据采集和处理、协同合作等功能的无线传感器节点组成的网络.它是当今技术发展的一个热点,尤其在军事领域.无线传感网对所使用的传感器有一些严格的限制条件.首先,传感器的功耗要低;其次是精度要高,A/D转换的分辨率为16位;最后是传感器的体积要小.一般而言,无线传感网总是优先使用微型传感器,只是在其功能不能满足要求的条件下才考虑传统的机械式传感器.     

浅谈无线传感器网络

要做到目视千里,耳听八方是人类长久的梦想,现代卫星技术的出现虽然使人们离这目标又进了一步,但卫星高高在上,洞察全局在行,明察细微就不管用了。这个时候,本文的主角一无线传感器网络就排上用场了。将大量的传感器节点遍撒指定区域,数据通过无线电波传回监控中心,监控区域内的所有信息就会尽收观察者的眼中了。     

无线传感器网络协议探究

随着物联网技术的深入发展,无线传感器网络的应用也越来越广泛.然而,无线传感器网络的技术还有待进一步的发展,也促使人们对于无线传感器网络协议的深入探究.本文针对无线传感器网络协议的网络层协议和MAC层协议的分类做了详细的描述和总结,为后续人们进一步研究做好铺垫.     

多总线控制的无线传感器网络

为了实现传感器节点之间无线通信并组网,开发了一种将各多总线器件集成到一起进行无线温、湿度测量的网络系统.系统各节点主要包括由SPI总线控制的无线射频器件QRF-0400,I~2C总线控制的硬时钟器件PCF8563,以及单总线控制的温、湿度传感器等.节点通过无线射频器件将传感器采集的温、湿度实时传递到监控主机,工作结束自动进入睡眠模式以降低节点功率,延长工作寿命.实验表明,节点在80m范围内自动组网并采集周边环境的温、湿度,误差低于0.01°.     

一种无线传感网络代码分发协议的研究

无线传感器网络的分发协议用于更新节点程序和发送控制指令,目前普遍采用的分发协议存在传输数据量和能耗过大的问题.为此提出一种无线传感网络代码传播与维护的自调整算法,并通过设计分发协议测试系统进行算法性能测试.实验结果表明该算法能有效调节网络中数据包的传输速度,减少数据包传输量,降低能量损耗.     

A proposal of a wireless sensor network routing protocol

This paper presents a proposal of a routing protocol to Wireless Sensor Networks, called SHRP (Simple Hierarchical Routing Protocol), whose primary objective is to save battery energy. SHRP also provides both reliability and a load balance solution. As a novel proposal, it is a proactive protocol that chooses efficient routes, by selecting just the nodes that can contribute to extend the network lifetime. In addition this protocol is also able to inform to a central point about any possible disconnection caused by a reduction of battery power or a long interference period. The data defined by SHRP protocol can be aggregated during the sending and forwarding tasks. Redundant data are not sent, which contributes to energy saving. This protocol uses the IEEE 802.15.4 under of CC2420 radio chips and it has been implemented on TinyOS operation system.     

Monitoring power transmission lines using a wireless sensor network

Power transmission is the bulk transfer of electrical energy from power plants to sub‐stations. A wireless sensor network is a promising technology for transmission line monitoring due to its low cost, easy installation, large‐scale coverage, and fault tolerance characteristics. A wireless sensor network is application‐specific; therefore, we investigate the new features and requirements of the wireless sensor network used in transmission line monitoring. Then, we propose an efficient wireless sensor network framework, which includes a clustering algorithm to simplify network management and to balance the network's energy consumption and a hybrid media access control (MAC) (H‐MAC) protocol to handle traffic variability. The framework takes advantage of the features of network topology and traffic pattern to optimize the protocols' performance on real time and energy efficiency. The results indicate that the H‐MAC shows a significant improvement in the network's reliability, real‐time performance, and energy efficiency, and the cluster hierarchy can balance the network's energy consumption. Furthermore, the cluster hierarchy also prolongs the network's lifetime. Copyright © 2014 John Wiley & Sons, Ltd.