A Localization Scheme in Wireless Sensor Networks

在無線感測網路中定位方法之設計

李育奇(Yu-Chee Lee)

指導教授 ： 廖文華

大同大學/經營設計學院/資訊經營學系所/碩士(2006年)

摘要

定位(Localization)是無線感測網路目前重要的議題之一，因為感測節點通常是隨機分布在一個區域.目前已提出許多定位演算法.這些方法可以分成兩類：範圍基礎(Range-based)和無範圍基礎(Range-free).範圍基礎的方式利用測距的方式或是測量角度等方式，利用昂貴的特殊硬體來達到良好的準確率。另一方面，無範圍基礎只利用接收訊息來支援定位，所以準確性較差。
我們提出一個利用行動參考點(Mobile anchor)的低成本無基礎範圍定位方法。行動參考點有裝載全球衛星定位系統(GPS)，並且會邊移動邊廣播它的座標給感測區域中的感測節點。當感測節點收集足夠的定位封包(Beacon)時，它們就能夠自己計算出自己的位置。系統模擬結果顯示我們提出的方法能在定位感測節點的數量方面達到最好的成效，而且不需要用太多的行動參考點。

關鍵字

感測網路 ； 定位

並列摘要

Localization is an important topic in wireless sensor networks because sensor nodes are randomly scattered over a region and they get connected into network on their own. Many localization algorithms have been proposed. These localization protocols can be divided into two categories: range-based and range-free. The range-based techniques use distance estimates or angle estimates to achieve fine accuracy with expensive specific hardware. In the other hand, the range-free mechanisms depend on the contents of received message to support coarse accuracy. In this thesis, we present a lightweight range-free localization scheme using mobile anchor nodes. The anchor node equipped with GPS broadcasts its coordinates to the sensor nodes as it moves through the network. As the sensor nodes collect enough beacons, they are able to calculate their locations locally. Simulation results show that the proposed scheme achieves best performance in percentage of localized sensor nodes without many mobile anchors.

並列關鍵字

sensor network ； sensor ； localization

參考文獻

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[4] N. Bulusu, J. Heidemann and D. Estrin, “GPS-less Low Cost Outdoor Localization for Very Small Devices,” IEEE Personal Communications Magazine, October 2000.

[5] L. Doherty, K. Pister and L. E. Ghaoui, “Convex Position Estimation in Wireless Sensor Networks,” IEEE InfoCom 2001, April 2001.