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Suk Lee Jee-Hun Park Kyoung-Nam Ha Kyung-Chang Lee 《International Journal of Precision Engineering and Manufacturing》2009,10(2):45-52
This paper examines the feasibility of using the IEEE 802.11b protocol for wireless networked control systems (NCSs). The
IEEE 802.11b protocol is not suitable for industrial networking because the medium access control method is contention-based
CSMA/CA, which exhibits unstable performance with an unbounded delay distribution under heavy traffic. To avoid these limitations,
we present a four-layer architecture for IEEE 802.11b based on the network driver interface specification (NDIS) combined
with a virtual scheduling algorithm. We compared the performance of the NDIS-based wireless NCS to that of a conventional
wireless NCS. Experimental results showed that the NDIS-based four-layer architecture for IEEE 802.11b is a very promising
alternative for wireless industrial networking. 相似文献
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基于无线传感器网络的煤矿监测预警系统 总被引:1,自引:0,他引:1
现有的有线煤矿监测预警系统只能在主矿道中应用,而复杂的地下工作区域仍是监测预警的"盲区".为了能够有效地解决这一问题并且减少事故的发生,本文提出了一种基于无线传感器网络和嵌入式平台的监测预警系统.通过传感器,对环境中CO、CH4、温度、湿度、光强等值进行监测.该系统采用了IEEE802.11MAC协议CSMA/CA,以及DCF模式.同时采用了MESH无线传感器网络分析与管理平台,利用此平台收集每一个节点的信息,进行数据汇聚与进一步数据分析,根据所收集的各节点数据自动生成相应图表和做出超限报警提示. 相似文献
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将用于替代现行版本IP协议IPv4的下一代IP协议IPv6(Internet Protocol Version 6)应用于嵌入式无线传感网络中,增大了地址空间,灵活简洁的IP报文头格式,有效地解决IP地址匮乏等应用问题,通过一种基于地址的无线传感网络系统,通过支持无线传感网络的6LoWPAN标准,使IEEE 802.15.4链路支持基于IPv6的通信,将多个监测终端的数据直接通过Internet主干网提供给任何一台接入Internet的普通PC访问单元,并将这种方法应用于树木生长监测系统. 相似文献
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ZigBee无线传感器网络技术在工业自动化监测中的应用 总被引:9,自引:0,他引:9
纪金水 《工业仪表与自动化装置》2007,(3):71-76
首先介绍了基于IEEE 802.15.4标准的ZigBee网络结构的技术特点、传感器节点的结构.分析了ZigBee无线传感器网络与蓝牙、Wi-Fi等其他无线通信技术的特点,最后对ZigBee无线传感器网络技术在工业自动化监测及其他方面的应用进行了分析. 相似文献
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通过对支持工业现场设备实时通信控制网络的研究,为通信协议的改进和实际工程应用提供指导。从周期性信息时延的确定性、有界性和网络性能出发,对CAN总线(CSMA/CA)、Ethernet(CSMA/CD)、Profibus总线(混合介质访问方式)和FF总线(集中介质访问方式)的通信机制进行定量和定性的对比分析。由信息负载率与吞吐量、平均信息时延、通信冲突率和网络利用率的关系可知,CAN总线在诸多性能方面优于Ethernet,FF总线在实时性方面优于Profibus总线。因此CAN总线特别适合于短通信距离的基于事件触发的现场信息实时通信,FF总线适合于对周期性信息具有严格实时性要求的应用场合。 相似文献
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《Measurement》2016
The performance metrics of IEEE 802.15.4 standard make it an only dominant option in short-range environmental monitoring and control applications. The heterogeneous sensor and actuator nodes based on the wireless technology are deployed into the smart building environment. Wireless technology deployed in building environment suffers from interference from different communication protocols operating in the same unlicensed ISM band, apart from the attenuation loss. A designer could not ignore these factors in the smart building because the adverse effect of these issues on system performance is considerable. Most of the researchers reported this but not with the aspects of the smart building. This research paper reports on the detailed experimental analysis and mitigation for different types of interference, the direction of arrival and attenuation losses associated with smart building condition. This research also tries to find the mitigation by direction of arrival of the radio signal. Our research aims to generate the customized methodology that will support and assist the smart building system designer to evaluate and measure the on-site performance so that these assessments will be precise, efficient and accurate. A realistic, smart home solution is applied to the building. 相似文献
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Pedro Mestre Carlos SerôdioAgostinho Azevedo Hélder CorreiaIsabel Bentes Carlos Couto 《Measurement》2011,44(6):1084-1095
Costs associated with the collection process of recyclable materials can be optimised if the correct prediction of when containers are ready for collection is made. To achieve this, data about the filling rate of containers must be collected. This data gathering is normally done by operators who estimate the filling rate and write it down on a form. An automated sensing system which evaluates the filling rate of containers and transmits it to a database for future analysis can help to improve the efficiency of collection systems. An autonomous wireless sensor used to gather data about the filling rate of containers for recyclable materials, is introduced in this paper. It is based on ultrasonic transducers to assess the filling rate and it uses IEEE 802.15.4 for wireless communications. The sensor sends its data to the collection truck as it approaches the container. This system has been successfully tested in the city of Mirandela in Portugal. 相似文献
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本文介绍了局域网的基本概念和标准,局域网使用的传输媒体,目前企业组建局域网常用的局域网技术及其应用,包括CSMA/CD媒体访问控制、共享以太网、交换以太网、快速以太网、千兆以太网,并简单描述了无线局域网及其相关应用,对企业组建局域网提出了一些建议. 相似文献
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讨论了如何将固态电化学传感器与无线传感器网络相结合,来实现机动车尾气在线监测.首先提出了系统的工作原理和设计框架;在系统构成上,采用传感器节点、基站、数据处理监控中心的三层结构;最后重点研究了TiO2氧敏材料传感器的检测方法和CSMA/CA算法的实现机理.从而实现了机动车尾气在线监测功能,对城市空气的净化和生态环境的平衡起到良好促进作用. 相似文献
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针对多次煎炸食用油会产生致癌物的严重安全问题,提出基于Zigbee无线传感器网络食用油实时监测系统的研究方案。通过采集煎炸食用油的极性组分等参数来对其预处理、A/D转换、数据分析等,通过串口将数据传输至PC机,并通过监控软件进行显示、分析和存储。采用CC2530无线射频收发芯片IC-SoC为核心设计节点硬件,以Z-Stack协议栈作为节点软件,ZigBee采用CSMA/CA机制,有效解决了多个传感器节点同时发数据给协调器带来的信道拥塞冲突问题。该方案成本低廉、性能稳定、易于扩展、方便快速地组建实时监测网络系统,极大地提高生产企业的生产效率。 相似文献
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基于ZigBee技术的无线电能采集终端的设计 总被引:3,自引:0,他引:3
本文提出了一种基于ZigBee技术实现的三相电能无线采集终端的设计方案,分析了从电能测量到数据收发过程的系统工作原理。在电能测量部分,利用ADI公司的一种高精度三相电能测量IC ADE7758作为电能测量芯片,使用Microchip公司的高性能单片机PIC18LF4620作控制器。在数据收发部分采用支持IEEE802 15.4无线通信协议的ZigBee技术,用Chipcon公司的射频芯片CC2420,实现采集的电能数据的无线收发通信。该系统可以实现对三相电能的无线自动采集功能。 相似文献
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基于遗传算法的网络控制系统调度优化研究 总被引:11,自引:0,他引:11
网络控制系统NCS(Networked Control system)是基于网络的分布式控制系统,具有强实时性。结合控制网络的实时调度与系统控制性能,应用单调速率RM(Rate Monotonic)方法对一组周期性的网络控制传输任务进行调度,采用遗传算法实现NCS的调度优化,同时满足了网络传输的优化调度与控制系统传输误差最小化的要求,提高了网络控制系统的性能,最后给出了优化实例。 相似文献
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Industrial high-speed wireless synchronous data acquisition system with real-time data compression 总被引:1,自引:0,他引:1
In this paper, an industrial wireless data acquisition system (WDAS) is presented. This system aims to change the inflexibility of wired system and improve the wireless transmission rate. First, the WDAS system consists of one wireless gateway and some wireless data acquisition terminals (WDAT), and IEEE 802.11n protocol is used to construct a multipoint distribution network. Then, in order to simplify the synchronous method and the data packet structure, we design a synchronous solution which adopts the console aided control method. The adaptive frequency and amplitude (AFA) compression algorithm is employed to reduce the data redundancy. Consequently, system can transmit more data by limited bandwidth. Last, some experiments of the compression algorithm are given to show the effectiveness of the AFA algorithm. By using the proposed system, distributed signals are synchronously measured and, hence, real-time analysis can be realized. 相似文献
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针对汽车控制系统CAN总线在处理周期性信号和随机性信号时具有不确定性和信息易死锁等缺陷问题,把服务于时间触发的均匀装载(AL)算法和服务于事件触发的动态优先级提升(DPP)算法相结合,提出了一种基于时间触发的控制器局域网(TTCAN)协议的混合调度策略,介绍了混合调度算法原理及实时性分析方法,构建了基于混合算法的汽车TTCAN系统矩阵,通过应用实例分析,验证了该方案满足汽车控制系统的实时性要求. 相似文献