基于ZigBee的无线传感器网络定位方法研究

发布时间：2018-01-06 03:15

本文关键词：基于ZigBee的无线传感器网络定位方法研究　出处：《哈尔滨工业大学》2014年硕士论文　论文类型：学位论文

【摘要】：近些年来，无线传感器网络获得了快速发展的机会，对于无线传感器网络中的关键技术之一—节点定位技术，国内外学者均提出了各种不同的方法和算法。但是，这些算法均存在一定的局限性，比如算法的分段性和误差处理方面都有待改善，达到的定位精度还有提升空间。因此，，开展对无线传感器定位的研究并提高定位精度具有重要意义。针对定位过程中算法分段性方面存在的不足，本文改进了基于TLM(Threshold Localization Method)策略的定位方法，改善传统传感器节点使用单算法的局面。该方法中，当节点距离小于5m时，利用基于RSSI(Received SignalStrength Indicator)改进测距算法进行距离计算；当距离大于5m时，利用基于DV-Hop改进非测距定位算法进行距离计算。针对误差处理方面存在的不足，本文在测距算法改进过程中采用最小二乘方法对RSSI-d曲线进行数据拟合处理，在非测距算法改进过程中采用DV-Hop中连通度不足的分散节点进行了误差分析，整个误差处理实现了分段。最后在坐标计算时采用加权的计算方法，对距离近的节点赋予更大的权值，使坐标计算越接近实际。本文设计了一个无线传感器网络定位系统验证上述改进方法的有效性，该系统由硬件和软件两部分构成。硬件部分由传感器节点、网关、移动小车和上位机构成，软件部分由IAR、ZigBee协议栈Z-Stack、定位图形监控软件Z-Location Engine和LabVIEW绘制的轨迹运行控制平台构成。在实验室进行实验验证：在5m5m的小范围内，对RSSI改进前和改进后的算法进行了验证，得出相对误差减小13.9%；在6m12m的范围内对TLM策略的定位方法进行验证，得出相对误差减小22.2%。实验结果验证了采用TLM策略更能准确反映实际环境中随着距离的不同采用不同算法带来的优越性，定位相对误差减小，改善了传统单独利用RSSI或者DV-Hop定位造成相对误差较大的状况。
[Abstract]:In recent years, wireless sensor networks (WSN) have gained the opportunity of rapid development, for one of the key technologies in wireless sensor networks-node location technology. Scholars at home and abroad have put forward a variety of different methods and algorithms. However, these algorithms have some limitations, such as the segmentation and error processing of the algorithm need to be improved. Therefore, it is of great significance to research and improve the positioning accuracy of wireless sensor. This paper improves the localization method based on TLM(Threshold Localization method. In this method, the node distance is less than 5m. The distance is calculated by using the improved ranging algorithm based on RSSI(Received SignalStrength indicator. When the distance is more than 5 m, the distance is calculated by using the improved non-distance location algorithm based on DV-Hop. In view of the shortcomings of error processing, the least square method is used to fit the RSSI-d curve in the improvement of ranging algorithm. In the improvement process of the non-ranging algorithm, the scattered nodes with insufficient connectivity in DV-Hop are used to analyze the error, and the whole error processing realizes the segmentation. Finally, the weighted calculation method is used in the coordinate calculation. A larger weight is given to the nearest node, which makes the coordinate calculation closer to the reality. This paper designs a wireless sensor network positioning system to verify the effectiveness of the improved method. The system is composed of hardware and software. The hardware part is composed of sensor nodes and gateways. The software is composed of IARX ZigBee protocol stack Z-Stack. The location-graphics monitoring software Z-Location Engine and the trajectory control platform drawn by LabVIEW are constructed. The experimental results in the laboratory are as follows: within a small range of 5m5m. The algorithm before and after the improvement of RSSI is verified, and the relative error is reduced by 13.9. The location method of TLM strategy is verified in the range of 6m12m, and the relative error is reduced by 22.2%. The experimental results show that the TLM strategy can more accurately reflect the advantages of different algorithms with different distances in the actual environment, and the relative error of location is reduced. The relative error caused by traditional RSSI or DV-Hop positioning is improved.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TP212.9;TN929.5

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