無線感測網路中戶外定位演算法

Outdoor Localization Algorithm in Wireless Sensor Networks

盧台威(Tai-Wei Lu)

指導教授 ： 陳永盛

元智大學/電機通訊學院/電機工程學系/碩士(2009年)

摘要

定位技術在無線感測網路中越來越重要。本論文提出定位演算法是利用無線感測網路中的接受信號強度。我們的方法是利用數學模型來估計目標物的座標位置。雖然三角定位演算法是一個利用接收信號強度來進行定位的基本方法，但是訊號衰減是其中的一個很大的誤差來源。為了增進定位的準確性，我們改善三角定位演算法，以減少訊號衰減所造成的定位錯誤。我們提出兩個演算法CIL和CIP只要利用4個參考節點的接收訊號強度資料去進行定位。我們的演算法的優點在於定位範圍不僅適用於矩形區域而且也適用於不規則區域。由實驗結果得知，本文提出的演算法在定位方面有很不錯的表現。

關鍵字

定位 ； 無線感測網路

並列摘要

Localization in wireless sensor networks gets more and more important. This thesis presents novel localization algorithms based on RSSI for wireless sensor networks. Our approach is using mathematical model to estimate the position of sensor node. Although trilateration is a basic method in localization based on RSSI, the path-loss can be a source of major error. For getting more accuracy, we improve trilateration algorithm to reduce path-loss. Circle Intersection Points (CIP) and Circle Intersection Lines (CIL) can easily use RSSI to estimate position by only four reference nodes. The advantage of algorithm we propose is not only suitable for the rectangular area but also suitable for the irregular area. The experimental results presented in this thesis demonstrate the ability of this system to estimate position with a high degree of accuracy.

並列關鍵字

ZigBee ； localization

參考文獻

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