在無線感測網路中，能夠找出散佈在網路中感測節點的位置是無線感測網路中熱門且重要的話題之一。無線感測網路擁有低成本、低頻寬、低能源耗損以及防碰撞機制，因此十分適合應用在大範圍且擁有自我組織能力的網路上。因此許多在無線感測網路定位技術上的研究都著重在於如何能夠在大範圍以及低成本的網路環境底下去偵測出感測節點的位置。
本篇論文提出一個可以提供低計算量、低通信量，並且以三邊定位演算法為基礎的分散式定位演算法，稱作節能可靠定位演算法。為了解決因測距誤差而造成傳統三邊定位不可靠的因素，節能可靠定位演算法提出一些機制去解決傳統三邊定位在可靠度上的問題。為了避免因選取可能造成定位錯誤的母節點而產生嚴重定位錯誤的情形，我們設計了一套可選擇可靠母節點的篩選機制。並且針對因測距誤差造成傳統三邊定位演算法失效的特殊情況，我們也提供一套自我修復機制。而本篇論文最主要的貢獻在於以上兩種加入三邊定位演算法的機制並不需要付出太多額外的計算以及信息交換，因此依然適用於分散式系統之中。實驗結果顯示節能可靠定位演算法成功地降低了過大定位誤差發生的次數，並且解決了三邊定位演算法因測距誤差而失效的誤失情形。

To locate sensor nodes in wireless sensor network is an important topic in many Wireless Sensor Network (WSN) applications. WSN provides low cost, low rate, low energy consumption, and anti-collision mechanism. These benefits make WSN easy to deploy in large scale and self-organization networks. So how to locate sensor nodes in large scale and cost-efficient WSN is a major challenge.
This study proposes a trilateration-based distributed localization algorithm named Robust and Energy-Efficient Localization (REEL) to support low-computation and low-communication services in the location-aware WSN applications. The REEL algorithm adopts an anchor-selection mechanism to achieve high robustness and solve the no-intersections problem in traditional trilateration localization algorithm. The main contribution of this paper is that high robustness is achieved without paying too much additional computation. The simulation results demonstrate that the REEL localization algorithm reduces the localization error rate without increasing computation complexities and resolves the no-intersection problem in trilateration localization scheme.

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