无线传感器网络实时性能分析及优化设计

发布时间：2018-05-12 18:27

本文选题：无线传感器网络 + 实时性　；参考：《兰州大学》2015年硕士论文

【摘要】：无线传感器网络综合了传感器技术、嵌入式计算机技术、网络与无线通信技术、分布式信息处理技术等,能够通过各种微型传感器协作实时监测、感知和采集各种环境或监测对象的信息,通过嵌入式系统处理信息,通过随机自组织无线网络以多跳中继方式将感知信息汇集到数据中心。无线传感器网络具有无需固定设备支撑,快速部署、自组网,不受有线网络约束的特点,无线传感网络可被广泛的应用于国防军事、工业控制、城市交通、环境监测、大型公共活动等社会信息化服务的各个领域。本文主要从无线传感器网络实时性方面展开研究。分析了无线传感器网络延迟的主要因素：节点内排队时延和节点间链路时延,分析了简单优先级调度算法与IEEE802.15.4协议的退避策略及算法,提出了节点系统动态优先级分组调度算法和支持优先级的CSMA/CA算法,并使用OPNET仿真分析评价了算法性能。动态优先级调度算法将结点缓冲区负载分为低、中、高阶段,对路由信息和数据信息进行优先级分组,特别对数据信息进行不同优先级分组,根据节点系统缓冲区负载变化,动态调整路由分组优先级改善网络的传输性能。仿真分析显示,低负载阶段,动态优先级调度算法与简单优先级调度算法执行相同的调度策略,但由于对数据分组进行了优先级设置,数据分组平均时延有所减少；中度负载阶段,降低部分高优先级分组的级别,数据分组平均时延比简单优先级调度策略降低；高负载阶段,采取一定的丢弃策略和优先级分配策略,可进一步降低了网络的平均时延。支持优先级CSMA/CA算法,通过设置竞争窗口CW值和退避指数BE值改善网络的传输性能。仿真结果显示,支持优先级的CSMA/CA算法能够提升网络中高优先级和中优先级分组的吞吐量,降低其平均时延,而且平均吞吐量和平均时延均有所改善。该算法通过调整CW值和BE值提供适应业务数据实时性要求的传输服务。
[Abstract]:Wireless sensor network integrates sensor technology, embedded computer technology, network and wireless communication technology, distributed information processing technology and so on. Sensing and collecting the information of various environment or monitoring objects, processing the information through embedded system, collecting the perceptual information to the data center by the way of multi-hop relay through random ad hoc wireless network. Wireless sensor network (WSN) has the characteristics of no fixed equipment support, rapid deployment, self-organizing network, and not restricted by wired network. Wireless sensor network can be widely used in defense, military, industrial control, urban traffic, environmental monitoring, wireless sensor network can be widely used in national defense, industrial control, urban traffic, environmental monitoring. Large-scale public activities and other social information services in all areas. This paper focuses on the real-time research of wireless sensor networks. This paper analyzes the main factors of delay in wireless sensor networks, including queueing delay within nodes and link delay between nodes, and analyzes the Backoff strategy and algorithm of simple priority scheduling algorithm and IEEE802.15.4 protocol. A dynamic priority grouping scheduling algorithm and a priority-supporting CSMA/CA algorithm are proposed, and the performance of the algorithm is evaluated by OPNET simulation. Dynamic priority scheduling algorithm divides node buffer load into low, middle and high stages, and carries on priority grouping for routing information and data information, especially for different priority groups of data information, according to the change of buffer load in node system. Dynamically adjust routing packet priority to improve the transmission performance of the network. The simulation results show that the dynamic priority scheduling algorithm performs the same scheduling strategy as the simple priority scheduling algorithm in the low load phase, but the average delay of the data packet is reduced due to the priority setting of the data packet. In the middle load stage, the average delay of data packet is lower than that of simple priority scheduling strategy, while in high load stage, some drop and priority allocation strategies are adopted, the average delay of data packet is lower than that of simple priority scheduling strategy. It can further reduce the average delay of the network. The priority CSMA/CA algorithm is supported to improve the transmission performance of the network by setting the CW value of the competition window and the Backoff index be value. Simulation results show that the priority-supported CSMA/CA algorithm can improve the throughput of high-priority and medium-priority packets, reduce the average delay, and improve both the average throughput and the average delay. By adjusting the CW and be values, the algorithm provides a transmission service that can meet the real-time requirements of traffic data.
【学位授予单位】：兰州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN929.5;TP212.9

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