共查询到19条相似文献,搜索用时 156 毫秒
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针对智能住宅建筑能效监管需求和现有热计量系统布线成本高、改造难度大的问题,将ISM频段无线收发芯片应用于无线热计量数据的传输过程中,对热计量传感器网络基本结构和工作原理进行了研究,开发了一种无线热计量数据传感器网络节点模块,设计了该节点模块的基本结构和主要电路,并重点介绍了其SPI接口连接方式及数据传输方法、无线收发芯片寄存器读写控制和热计量数据的无线收发过程。实验结果表明,所设计的无线热计量传感器网络节点模块在保证热计量数据稳定、可靠采集传输的同时,大大地增加了热计量传感器网络的灵活性和适用性,为住宅建筑能效数据的智能化采集、传输和管理提供了一种经济、高效的解决方法。 相似文献
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针对传统人工水质污染程度检测工作效率低、实时监测能力不强的问题,设计并实现了基于web网络优化协议的实时在线水质污染程度自动监测系统,系统利用无线传感器网络节点对区域水源水质进行监测,通过无线分组通信技术与宽带网络对数据进行远程传送,工作人员可实现web实时在线的水质信息查询、管理控制、数据收集、报警提示等操作,基于web的水质监测系统,提升了系统的可扩展性、易用性以及实时性等;系统硬件包括传感器模块、无线通信模块、单片机外围电路、以太网接口模块等;系统软件设计了web网络优化协议、系统监测平台、远程参数设置、驱动程序等内容;应用该系统对西安市护城河的水质进行污染程度监测,部署20个传感器监测节点,1个监测子站节点,1个远程web监测主站,分别监测河水中pH值、总磷浓度TP、化学耗氧量(COD)、氨氮浓度,连续采样两天时间,通过仿真实验表明,该系统实现了100%的通信成功率,网络之间访问速度是传统网络协议的5~8倍,无线传感器网络与远程监测工作稳定可靠,通信速率满足实时监测要求,适用于对城市水源水质污染程度的实时在线监测。 相似文献
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基于CDMA 1X的无线数传系统设计 总被引:6,自引:0,他引:6
CDMA 1X是中国联通推出的一种新型移动数据通信业务。系统以数传终端为核心,将现场的数据进行编码处理,并转换成在公网中传送的数据格式,通过中国联通的CDMA 1X无线数据网络进行传输,最终传送到监控中心IP地址。本文详细介绍无线数传系统的硬件组成和软件设计方法;阐述基于CDMA 1X业务实现数据无线传输的设计思路以及基于MSP430微处理器和CDMA模块CCl的数传终端设计方案;给出数传终端的硬件设计电路以及相关软件流程图等。该系统可以实现远程的数据传输,在许多无人值守并需要数据传输的场所可以得到广泛的应用。 相似文献
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Yuanyuan Zeng Cormac J. Sreenan Naixue Xiong Laurence T. Yang Jong Hyuk Park 《The Journal of supercomputing》2010,52(1):23-46
One of the main design challenges for wireless sensor networks (WSNs) is to obtain long system lifetime without sacrificing
system original performance such as communication connectivity and sensing coverage. A large number of sensor nodes are deployed
in redundant fashion in dense sensor networks, which lead to higher energy consumption. We propose a distributed framework
for energy efficient connectivity and coverage maintenance in WSNs. In our framework, each sensor makes self-scheduling to
separately control the states of RF and sensing unit based on dynamic coordinated reconstruction mechanism. A novel energy-balanced
distributed connected dominating set algorithm is presented to make connectivity maintenance; and also a distributed node
sensing scheduling is brought forward to maintain the network coverage according to the surveillance requirements. We implemented
our framework by C++ programming, and the simulation results show that our framework outperforms several related work by considerably
improving the energy performance of sensor networks to effectively extend network lifetime. 相似文献
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Wireless Sensor Networks (WSNs) collect and transfer environmental data from a predefined field to a base station to be processed and analyzed. A major problem in designing WSNs is coverage maximization, in which a given number of sensor nodes must be deployed in a way that maximizes area coverage of a given network, without violating practical constraints. This is a known NP-hard problem and thus requires metaheuristic approaches for practical problem sizes.Two metaheuristics, namely Genetic Algorithm and Particle Swarm Optimization are proposed to tackle this problem. Our new contributions include a partial use of heuristic initialization, new fitness function, modified virtual force algorithm, addition of a uniform deceleration to the calculation of inertia weight and addition of the influence of sub-populations’ head individuals. The proposed algorithms are comprehensively experimented and compared with the current state-of-the-art for the equivalent problem without obstacles. Experimental results not only suggest which algorithms should be applied to which cases, but also provide insights into parameter settings, effects of heuristic initialization and effects of virtual force algorithm in each case. These conclusions are meaningful for our future research on obstacles constrained area coverage problems related to connectivity and lifetime of WSNs. 相似文献
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GSM移动通讯网络系统是目前国内覆盖最广、可靠性最高、容量最大、保密性强的公共无线数字传输系统.GSM通信分系统在车载单元与监控中心之间进行数据传输,其性能优劣对车载定位系统起着十分重要的作用.结合实时UML状态机的直观、平台无关性特点和LSPN的理论分析能力,研究了GSM通信模块的工作模式,结合实例初步探索了该方法在移动通讯网络性能分析中的适用性. 相似文献
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Recently, wireless sensor networks (WSNs) have been used in various smart grid applications, including remote power system monitoring and control, power fraud detection, wireless automatic metering, fault diagnostics, demand response, outage detection, overhead transmission line monitoring, load control, and distribution automation. However, harsh smart grid environment propagation characteristics cause great challenges in the reliability of WSN communications in smart grid applications. To this end, the analysis of wireless link reliability and channel characterizations can help network designers to foresee the performance of the deployed WSN for specific smart grid propagation environments, and guide the network engineers to make design decisions for the channel modulation, encoding schemes, output power, and frequency band. This paper presents a detailed analysis of low power wireless link reliability in different smart grid environments, such as 500 kV outdoor substation environment, indoor main power control room, and underground network transformer vaults. Specifically, the proposed analysis aims to evaluate the impact of different sensor radio parameters, such as modulation, encoding, transmission power, packet size, as well as the channel propagation characteristics of different smart grid propagation environments on the performance of the deployed sensor network in smart grid. Overall, the main objective of this paper is to help network designers quantifying the impact of the smart grid propagation environment and sensor radio characteristics on low power wireless link reliability in harsh smart grid environments. 相似文献
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针对温室环境数据无线采集、视频监控及远程管理的需求,设计了一种基于无线传感器网络( WSNs)的智能温室环境监控系统。系统采用ZigBee和WiFi融合通信技术组成智能网关,其中,ZigBee无线通信设备用于采集温室环境数据,WiFi通信设备用于无线视频传输和远程通信。所设计系统既避免了传统温室环境有线监控安装和维护的繁琐,同时解决了ZigBee WSNs传输速率较低、无线传输距离较近的缺点,温室环境监控功能得到拓展。经过测试验证,正常情况下网络丢包率小于1%,系统实现了温室环境远程监控管理的各项性能,具有良好的应用性和可扩展性。 相似文献
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针对海水水质现场采样监测问题的困难性,提出了一种利用无线传感器网络技术和计算机技术的在线监测方案。方案涵盖感知层、网络层和应用层,通过把现有的水质传感器连接到微控制器上,利用无线传输模块实现点区域的数据汇集,汇集数据通过GPRS模块接入互联网中,上位机服务器接收和处理数据并把结果存放到数据库中。方案对无线传感器网络的布设做了简单的介绍,给出了监测网络的数据传输存储流程,并对上位机服务器程序和海水水质数据库的建设做了详细介绍。方案通过实物搭建和实验验证了可行性。 相似文献
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为了实现有线网络难以覆盖的远程数据传输,设计了基于NiosII系统的远程数据传输系统。系统中使用FPGA芯片的IP核构建NiosII控制系统和与3G模块通信的UART接口,同时设计了数据传输控制程序和通信协议,实现了通过3G无线网络的数据远程传输。针对电力系统的远程数据采集进行了测试,系统功能完善,运行可靠。 相似文献