【作者】 张锋辉；

【导师】 廖启征； 周晓光；

【作者基本信息】 北京邮电大学 ， 机械电子工程， 2010， 博士

【摘要】 近年来,无线传感器网络在环境监测领域的应用越来越得到国内外研究人员的重视。无线传感器网络粮情监测是指将无线传感器节点部署在粮面以上或粮堆中对粮食仓储环境进行监测的传感器网络。与现有的有线方式粮情监测系统相比,无线传感器粮情监测网络具有易于布设、多参数监测、覆盖范围大、易升级等优势；结合大中型储粮粮仓,研究无线传感器网络监测粮食仓储环境,对提高监测质量和监测性能具有很大的实用价值。本文针对粮食仓储监测的特点,构建无线传感器网络粮情监测组网部署方案,另外对提出的监测组网方案,以路由协议优化思想为指导,研究降低能量消耗的无线传感器网络数据收集协议。围绕以上主题内容,本文主要的研究内容和创新成果如下：(1)采用评估无线电波在粮堆中的能量衰减和统计节点数据丢包率相结合的方法,对无线信号在粮堆中的可靠传输距离进行了数值分析,得到了780MHz无线传感器节点在小麦粮堆中的每米能量衰减数值,其方法和结果对小麦粮堆中无线传感器节点的部署具有指导意义。(2)对无线传感器粮情监测部署方案进行了研究。根据大中型平房式粮仓的监测特点,提出了两种粮情监测组网部署结构,即测温电缆式传感器网络和携带传感器式传感网络；对可以推广应用的测温电缆式传感器网络进行了仿真和性能分析,提出了进一步网络优化的方向。(3)针对无线个人区域网络ZigBee适用于无线传感器网络应用方面,提出了一种将AODV路由协议与节点能量消耗情况相结合的能量有效型路由算法E-AODV jr.E-AODV jr算法能够同时降低路由开销和提高路由修复效率,将采用E-AODV jr协议的ZigBee网络应用于粮情监测组网,仿真结果表明,E-AODV jr协议提高了路由和数据传输效率,延长了节点生存时间。(4)分析了目前成簇节能协议存在的问题,提出了无线传感器网络非均匀分簇协议LBCP.该协议改进了分簇算法中的不现实假设条件,并综合考虑了时间同步、网络负载平衡、多跳、簇间干扰、节点剩余能量和周期型数据收集等因素,通过仿真验证得出,LBCP协议能够较LEACH协议更好的适用于周期采集型传感器网络,并有效地提高了网络的生存时间。将此算法应用于粮情监测组网并仿真分析,获得了对搭建原型系统有意义的参考数据。为了验证LBCP分簇收集协议的可行性,基于符合IEEEP802.15.4c规范的射频节点,详细研究了分簇组网协议相关机制的实现,结合仿真结果设计了时间同步和TDMA时隙调度方案。在试验粮仓中实施并验证了基于时间同步和TDMA时隙调度机制的成簇组网协议,并可以通过Internet对无线传感器网络的部署粮仓进行远程监测。更多还原

【Abstract】 In recent years, with the rapid development of wireless sensor networks (WSN), the application of collect the information for environment monitor has been paid more attentions by researchers. WSN-based measurement network for grain depot is the sensor network that most sensor nodes are buried in the grain or deployed in the grain surface. Compared to using wired sensors technology for the measurement system in large-scale barns, WSN-based measurement network has several outstanding advantages in easy deployment, multi-parameter monitoring and easy upgrade. Research of WSN technology for the measurement system in large-scale barns has a great practical meaning to improve the quality and performance of monitoring. This paper mainly focuses on the study of energy-efficient data gathing protocol based on measurement network for grain depot. Firstly, according to the characteristics of grain storage, building the wsn-based measurement network topologies. Secondly, based on the network topologies this paper study of energy-efficient routing protocol to extend lifetime of the measurement network. The main contributions of this thesis are as follows:(1) To get the wireless sensor nodes’transmission distance which is buried in the grain, attenuation theory in grain and packet loss rate were used. Through experiments and analysis, the 780MHz RF attenuation in wheat and the data transmission distance is gained. It is helpful in nodes’ deployment.(2) The sensor nodes deployment problem of WSN-based measurement network is explored. Based on the demand of monitoring large-scale barns, two network topologies for measurement system were proposed--WSN with temperature measurement cables and WSN with sensors. To evaluate the feasibility and the challenges of the first topology, some simulating experiments were designed. The results show that some methods need to be done to meet the network lifetime.(3) Aiming at ZigBee network for WSN applications, we firstly analyses the node energy consumption issues of AODV protocol and optimal energy routing mechanisms. Then to optimal AODV protocol for energy-efficiency usage, an improved routing algorithm, E-AODVjr, combining AODVjr with the node residual energy is proposed. E-AODVjr can reduce the packet delay with comparatively small in overload. The simulation experiment indicated that the performance of E-AODVjr protocol has remarkable improvement, and the life time of the network is extended obviously.(4) Investigates the currently clustering algorithms in wireless sensor networks,and then a clustering routing protocol LBCP combining the time synchronization protocol for environment monitor is proposed. In this new protocol, we introduce the time synchronization, load banlance, multi-hop mechanisms, and to avoid the inter cluster interference two methods are designed. Our simulation results shows that compared with the conventional LEACH protocol, the performance of LBCP protocol has remarkable improvement for data gathing networks, and the life time of the network is extended obviously. Using this protocol in measurement network for grain depot, we obtained meaningful simulation data.Based on the above achievements, we implement a data collection prototype based on LBCP and IEEE P802.15.4c wireless sensor nodes. We also describes time synchronization and TDMA schedule method detailedly. Our system is deployed in test Granary, experiment results show that all packets are successfully collected throuth Internet.更多还原