节点文献

基于嵌入式系统的井下人员跟踪定位系统的研究与设计

【作者】 薛艳江

【导师】 于德海;

【作者基本信息】 长春工业大学 , 计算机应用技术, 2010, 硕士

【摘要】 当前煤矿事故频发,其中井下的安全问题成为社会焦点.由于井下开采,煤层所释放的瓦斯等易燃气体因无法及时排出,且煤层离地表一般较深,一旦发生瓦斯爆炸等安全事故,极易造成井下人员的伤亡。能在最短时间内跟踪定位井下人员对挽救人员生命至关重要。目前,跟踪定位主要有GPS卫星定位,移动通信追踪定位,zigbee跟踪定位技术。ZigBee技术采用IEEE 802.15.4协议标准。由于基于2.4 GHz这一公共免费频带进行信号传输无需网络使用费.ZigBee芯片的价格现已降到3美元以下,因此,相比移动终端设备的价格.用zigBee建网络具有较大的成本优势。本文通过比较传统定位系统的优缺点,认为基于zigbee的无线定位系统以其技术先进、易于实现、成本造价低、易于普及等特点,将成为未来发展的趋势。ZigBee技术具有协议简单、成本低、功耗小、组网容易等优点,最适合应用于井下定位系统。作者深入研究了ZigBee技术的基本原理,深入分析了物理层、媒体访问控制层、网络层、应用层等各层协议。对井下人员定位系统的模拟、各部分在系统中的功能以及主要硬件选型进行了确定,研究了各种无线网络定位算法,提出一种实用的定位方法。由于zigbee定位系统中的定位节点一般是依靠自身携带的电池供电,寿命需达尽可能的长,因此如何减小通信过程中的能量消耗显得很重要。降低能量消耗、延长电池存活时间涉及到ZigBee的各层协议以及算法复杂度,本文分析研究了物理层、媒体访问控制层、网络层的问题并对APIT算法进行了改进,降低了算法复杂度和耦合度且定位精度在可接受范围内。本文对现有各种节能技术在本系统中应用的可能性深入研究后发现:物理层可以根据网络节点位置判断RSSI/LQI值调节发射功率大小。在MAC层采用支持节点在不同的状态之间切换来提高能量利用率。基于zigbee的井下人员跟踪定位系统中网络层的节能机制必须既考虑通信中能量消耗,又必须考虑到系统的耦合度,防止某部分节点的缺失而使定位失效。在矿井下一旦有事故发生,很可能造成大量节点通信中断,因此对耦合度的要求更加苛刻。最后,总结了全文,并提出了未来的工作方向。

【Abstract】 At present coal mine accidents, in which the mine safety issues into the public spotlight. Due to underground mining, coal seam gas released due to lack of timely and other flammable gases discharged, and the coal seam deep from the surface normal in the event of accidents such as gas explosion, very could easily lead to mine casualties. Be able to track the location in the shortest time to save the mine staff personnel vital for life. At present, the main GPS satellite positioning to track positioning, mobile communications to track location, zigbee track positioning technology.ZigBee technology uses IEEE 802.15.4 protocol standards. Because of this public free of charge based on the 2.4 GHz frequency band for signal transmission without network usage fees. ZigBee chip prices have dropped below 3 U.S. dollars, therefore, compared the price of mobile terminal equipment. Build networks with zigBee have greater cost advantages.In this paper, advantages and disadvantages of more traditional positioning systems that zigbee-based wireless location system for its advanced technology, easy to implement, cost-low cost, easy-to-universal characteristics, will become the future trend of development. ZigBee technology has an agreement simple, low cost, power consumption, easy networking, etc., most suitable for downhole positioning system.By in-depth study of the ZigBee technology, the basic principle of in-depth analysis of the physical layer, media access control layer, network layer, application layer protocol layers. Underground staff on the positioning system simulation, the various parts of the functions in the system and the main hardware selection was determined to study a variety of wireless network positioning algorithm, a practical location methods.Because of the location positioning system zigbee nodes are generally rely on their own portable battery-powered, take up as much as possible a long life, so how to reduce the energy consumption of the communication process seems very important. Reduce energy consumption and extend battery survival time related to different levels of ZigBee protocol and algorithm complexity, this article analysis of the physical layer, media access control layer, network layer of the questions and APIT algorithm has been improved to reduce the algorithm complexity and coupling and positioning accuracy within an acceptable range. In this paper, various existing energy-saving technologies applied in this system the possibility of in-depth study found that:the physical layer network nodes based on location to determine RSSI/LQI values adjust the size of transmission power. In the MAC layer to support node to switch between different states to improve energy efficiency. Zigbee-based tracking and positioning system for underground workers in the network layer energy-saving mechanism must take into account both communication energy consumption, but also must take into account the coupling degree of the system to prevent certain parts of the absence of Er Shi positioning node failure. In an underground mine if there is an incident, it may result in a large number of nodes in communication interrupt, so the coupling is more demanding requirements.Finally, sum up the text, and proposed future direction of work

【关键词】 zigBee低速率无线网络定位算法
【Key words】 ZigbeeLow data rateWirelessLocation algorithm
节点文献中: 

本文链接的文献网络图示:

本文的引文网络