WSN信道效率与定位应用关键技术的研究

【作者】 周磊；

【导师】 邢建平；

【作者基本信息】 山东大学 ， 通信与信息系统， 2007， 硕士

【摘要】 无线传感器网络融合了微电子、计算与通信等多种技术，在诸多领域有着广阔的应用前景，在交通控制领域也是研究的热点。本文以传感网络的城市交通应用为背景，围绕数据传输与定位相关技术展开研究，所做工作既有理论意义，又有一定实际应用价值。首先，无线传感器网络数据传输的有效性是关系到网络整体性能的关键技术之一，对网络的信道利用效率进行测算分析非常有必要。为此，本文提出了一种对无线传感网络MAC层信道利用效率进行测算的方法，该方法适用于基于竞争机制的MAC协议，可以从成帧效率、信道共享效率和冲突避免效率三个方面对MAC层的信道利用情况进行综合计算。同时用此法对典型MAC层协议S-MAC和IEEE 802.15.4的信道利用效率进行计算，结合网络场景仿真与IEEE 802.11进行了比较，结果是IEEE802.15.4协议在低速率数据传输场景下有着最佳的信道利用率。然后，对基于距离的无线传感器网络定位算法进行研究，定位算法运算复杂度、定位精度与硬件要求之间存在着矛盾。总结常用算法的不足，针对在交通领域应用的大尺度环境下电磁波传播模型，提出了一种具有较低计算量的优选残差加权算法(SRwgh)。该算法不需要环境的统计模型和信道的先验知识，也无需反复通信。在保证精确度的前提下，克服了未知节点所能接受的信标节点数量增大时，计算量急剧增大问题，降低了硬件实现复杂度。最后，设计了一种TDMA大区制分布式车辆传感网络系统的详细架构，给出了物理层、数据链路层和网络层的协议，分析了CRC校验方法。基于GPS秒脉冲精确的时钟上升沿同步，解决了系统大容量问题。基于嵌入式通信控制器和具体硬、软件设计了系统的移动单元和中心控制单元。按数据通信层、车辆管理层、用户界面管理层划分模块，基于VC开发平台集成MapX矢量电子地图设计了中心监控软件。另外，简单给出了一种新型司机饮酒状态检测的ZnO基交通酒敏传感器研制过程和方法，进行了酒敏检测电路和系统集成的设计与实现。更多还原

【Abstract】 WSN, aggregating several techniques such as micro-electronics, computing and communications etc, are promising techniques for many applications, such as traffic control area. In this paper, we take the city traffic as the application background and present the research on data transmission and localization for WSNs. It is valuable both in theoretics and applications.Firstly, it is necessary to measure the WSN channel efficiency because its impact to the whole performance of network. We presented a method for calculating the MAC layer channel utilized efficiency, analyzed two protocols in wireless sensor network such as S-MAC and IEEE 802.15.4, calculated the MAC layer channel utilized efficiency from the perspective of frame forming efficiency, MAC procedure overhead efficiency and collision avoidance, meanwhile, compared to IEEE 802.11 protocol and illuminated with simulation.The application area of the both protocols S-MAC and IEEE 802.15.4 is emphasized.And then, we researched the range-based localization scheme for WSNs. The traditional schemes had conflicts in complexity, precise and demand of hardwire. Considering the localization schemes in common use, we presented a low computional localization scheme refered as SRwgh under electromagnetism propagation model of the large scale environment, and this scheme did not need the statistical model of environment and the apriori knowledge of channel, and neither the communication repeatly. This scheme can overcome the problem of rapid augmentation of computation when the number of learned anchors increased and reduced the hardware complexity.Lastly, a system construction based on distributed TDMA big-section of vehicle sensing network is proposed. The protocol of physical layer, data-link layer and network layer is given out and the method of CRC is analysed, and the problem of huge-capacity in system is solved using the accurate synchronize of GPS PPS (pulse per second). The system mobile unit and center control unit are designed based on embedded communication controller, and according to the module division: data communication layer, vehicle management layer, customer interface management layer, the center monitoring software is achieved, which combined the MapX vector eletric map in VC envioriment.In additation, given out the develop procedure of ZnO alcohol gas sensor for detecting drinking state of drivers, and designed the alcohol sensing detecting circuit as well as system intergrating.更多还原